Optimization of the BNCT filter
International Nuclear Information System (INIS)
The Czech Boron Neutron Capture Therapy (BNCT) facility works by an epithermal neutron beam installed at the LVR-15 reactor at Rez near Prague. Several configurations of moderating and shielding materials have been designed in order to ensure appropriate parameters of the beam. The beam filter consists of cylindrical layers of Al, AlF3 and Ti. To decrease the gamma two layers of Pb are implemented. The filter geometry and composition has been optimized with the aim to increase the epithermal neutron fluence rate and decrease the fast neutron dose rate using the MCNP-4B Monte Carlo code with the DLC-189 library. Suitable patterns of the reactor core were also studied especially in regard to a possible installation of fuel units close to the filter input. Results of calculations show that the optimized variant of the reactor core is able to increase the intensity of the fast neutron source incident to the filter by a factor of 2.0. An experimental verification of the beam parameters was performed using different measurement techniques. The neutron energy spectrum was measured with a set of activation foils, by a Bonner spheres spectrometer and a fast neutron spectrometer with a stilbene crystal. The fast neutron kerma rate was calculated from the spectral measurement. Al-P TLD were used to measure the photon absorbed dose. The beam parameters were measured at 10 MW and were found as follows: the epithermal neutron fluence rate (an energy range from 1 eV to 10 keV) of 9.29 x 1012 m-2 s-1, the fast neutron kerma rate in tissue of 2.63 Gy h-1 and the incident gamma dose rate in tissue of 29 Gy h-1. (author)
Design of a BNCT facility at HANARO
International Nuclear Information System (INIS)
Based on the feasibility study of the BNCT at HANARO, it was confirmed that only thermal BNCT is possible at the IR beam tube if appropriate filtering system be installed. Medical doctors in Korea Cancer Center Hospital agreed that the thermal BNCT facility would be worthwhile for the BNCT technology development in Korea as well as superficial cancer treatment. For the thermal BNCT to be effective, the thermal neutron flux should be high enough for patient treatment during relatively short time and also the fast neutron and gamma-ray fluxes should be as low as possible. In this point of view, the following design requirements are set up: 1) thermal neutron flux at the irradiation position should be higher than 3x109 n/cm2-sec, 2) ratio of the fast neutrons and gamma-rays to the thermal neutrons should be minimized, and 3) patient treatment should be possible without interrupt to the reactor operation. To minimize the fast neutrons and gamma-rays with the required thermal neutrons at the irradiation position, a radiation filter consisting of single crystals of silicon and bismuth at liquid nitrogen temperature is designed. For the shielding purpose around the irradiation position, polyethylene, lead, LiF, etc., are appropriately arranged around the radiation filter. A water shutter in front of the radiation filter is adopted so as to avoid interrupt to the reactor operation. At present, detail design of the radiation filter is ongoing. Cooling capabilities of the filter will be tested through a mockup experiment. Dose rate distributions around the radiation filter and a prompt gamma-ray activation analysis system for the analyses of boron content in the biological samples are under design. The construction of this facility will be started from next year if it is permitted from the regulatory body this year. Some other future works exist and are described in the paper. (author)
Design of a BNCT facility at HANARO
International Nuclear Information System (INIS)
Based on the feasibility study of the BNCT at HANARO, it was confirmed that only thermal BNCT is possible at the IR beam tube if appropriate filtering system be installed. Medical doctors in Korea Cancer Center Hospital agreed that the thermal BNCT facility would be worthwhile for the BNCT technology development in Korea as well as superficial cancer treatment. For the thermal BNCT to be effective, the thermal neutron flux should be high enough for patient treatment during relatively short time and also the fast neutron and gamma-ray fluxes should be as low as possible to avoid high dose on the patient during treatment. In this point of view, the following design requirements are set up; 1) thermal neutron flux at the irradiation position should be higher than 2 X 109 n/cm2 . sec, 2) ration of the fast neutrons and gamma-rays to the thermal neutrons should be minimized, and 3) patient treatment should be possible during reactor operation. To minimize the fast neutrons and gamma-rays with the required thermal neutrons at the irradiation position, a radiation filter consisting of single crystals of silicon and bismuth at liquid nitrogen temperature is design d. For the shielding purpose around the irradiation position, polyethylene, lead, LiF, etc., are appropriately arranged around the radiation filter. A water shutter in front of the radiation filter is adopted so as to avoid interrupt to the reactor operation. While the shutter is filled in water during on power, the radiation level in the irradiation room is sufficiently low for the preparation work for patient irradiation including temporary surgery. At present, detail design of the radiation filter is ongoing. cooling capabilities of the filter will be tested through a mockup experiment. Dose rate distributions around the radiation filter are under analysis for the configuration of the irradiation room. A prompt gamma-ray activation analysis system for the analyses of boron content in the biological samples, is
Application of multiprocessor calculations in IRT BNCT channel design
International Nuclear Information System (INIS)
The Research Reactor IRT (IRT) Sofia, of the Institute for Nuclear Research and Nuclear Energy of the Bulgarian Academy of Sciences (INRNE) is in a process of reconstruction. The technical project includes an arrangement of Boron Neutron Capture Therapy (NCT) facility. The development of BNCT for head and neck cancer, and liver cancer is one of the main tasks in the Program for sustainable application of the reactor. The physical design of the BNCT channel proved itself to be a heavy demanding task in terms of investigation of the filter/moderator materials' physical behaviour that will be suitable for the IRT reactor's specific conditions. The IRT-Sofia NCT beam tube optimization study and the followed investigations of different filter/moderator materials and in-phantom biological doses would require a big number of sophisticated 3-dimensional calculations. The computational time for performing these calculations with the current computer setup would be unacceptably great. That is why a new version of the MCNP code with extensive capabilities for multiprocessor calculations was introduced. The compatibility with the results obtained in calculations with previous version is shown. The inheritance between the calculations sequence is justified. The gain in speed is demonstrated. (authors)
Spatial and spectral characteristics of a compact system neutron beam designed for BNCT facility
International Nuclear Information System (INIS)
The development of suitable neutron sources and neutron beam is critical to the success of Boron Neutron Capture Therapy (BNCT). In this work a compact system designed for BNCT is presented. The system consists of 252Cf fission neutron source and a moderator/reflector/filter/shield assembly. The moderator/reflector/filter arrangement has been optimized to maximize the epithermal neutron component which is useful for BNCT treatment of deep seated tumors with the suitably low level of beam contamination. The MCMP5 code has been used to calculate the different components of neutrons, secondary gamma rays originating from 252Cf source and the primary gamma rays emitted directly by this source at the exit face of the compact system. The fluence rate distributions of such particles were also computed along the central axis of a human head phantom
Spatial and spectral characteristics of a compact system neutron beam designed for BNCT facility
Energy Technology Data Exchange (ETDEWEB)
Ghassoun, J. [EPRA, Departement de Physique, Faculte des Sciences Semlalia, B.P. 2390, 40000 Marrakech (Morocco)], E-mail: ghassoun@ucam.ac.ma; Chkillou, B.; Jehouani, A. [EPRA, Departement de Physique, Faculte des Sciences Semlalia, B.P. 2390, 40000 Marrakech (Morocco)
2009-04-15
The development of suitable neutron sources and neutron beam is critical to the success of Boron Neutron Capture Therapy (BNCT). In this work a compact system designed for BNCT is presented. The system consists of {sup 252}Cf fission neutron source and a moderator/reflector/filter/shield assembly. The moderator/reflector/filter arrangement has been optimized to maximize the epithermal neutron component which is useful for BNCT treatment of deep seated tumors with the suitably low level of beam contamination. The MCMP5 code has been used to calculate the different components of neutrons, secondary gamma rays originating from {sup 252}Cf source and the primary gamma rays emitted directly by this source at the exit face of the compact system. The fluence rate distributions of such particles were also computed along the central axis of a human head phantom.
Spatial and spectral characteristics of a compact system neutron beam designed for BNCT facility.
Ghassoun, J; Chkillou, B; Jehouani, A
2009-04-01
The development of suitable neutron sources and neutron beam is critical to the success of Boron Neutron Capture Therapy (BNCT). In this work a compact system designed for BNCT is presented. The system consists of (252)Cf fission neutron source and a moderator/reflector/filter/shield assembly. The moderator/reflector/filter arrangement has been optimized to maximize the epithermal neutron component which is useful for BNCT treatment of deep seated tumors with the suitably low level of beam contamination. The MCMP5 code has been used to calculate the different components of neutrons, secondary gamma rays originating from (252)Cf source and the primary gamma rays emitted directly by this source at the exit face of the compact system. The fluence rate distributions of such particles were also computed along the central axis of a human head phantom. PMID:19168369
International Nuclear Information System (INIS)
Following the formation in 1987, of both the European Collaboration group on Boron Neutron Capture Therapy (BNCT) and the Petten BNCT group, steps were taken to design and implement an epithermal neutron beam for BNCT applications at the High Flux Reactor (HFR) at Petten. The installation would serve as a European facility, while once the modality of BNCT is proven would be the pathfinder for implementation of BNCT at other European nuclear sites. Due to its favorable nuclear and geometric characteristics, the beam tube HB11 was chosen as the candidate beam tube for BNCT applications. To reconfigure the beam tube to produce the required epithermal neutrons, it was first necessary to remove the existing mirror system and then to install the appropriate filter materials. Due to the fixed operating schedule of the HFR, with only one long shut-down period per year during the summer weeks for maintenance and upgrading actions, installation of the new facility was planned for the summer stop period in 1990
A multi-dimensional procedure for BNCT filter optimization
International Nuclear Information System (INIS)
An initial version of an optimization code utilizing two-dimensional radiation transport methods has been completed. This code is capable of predicting material compositions of a beam tube-filter geometry which can be used in a boron neutron capture therapy treatment facility to improve the ratio of the average radiation dose in a brain tumor to that in the healthy tissue surrounding the tumor. The optimization algorithm employed by the code is very straightforward. After an estimate of the gradient of the dose ratio with respect to the nuclide densities in the beam tube-filter geometry is obtained, changes in the nuclide densities are made based on: (1) the magnitude and sign of the components of the dose ratio gradient, (2) the magnitude of the nuclide densities, (3) the upper and lower bound of each nuclide density, and (4) the linear constraint that the sum of the nuclide density fractions in each material zone be less than or equal to 1.0. A local optimal solution is assumed to be found when one of the following conditions is satisfied in every material zone: (1) the maximum positive component of the gradient corresponds to a nuclide at its maximum density and the sum of the density fractions equals 1.0 or, and (2) the positive and negative components of the gradient correspond to nuclides densities at their upper and lower bounds, respectively, and the remaining components of the gradient are sufficiently small. The optimization procedure has been applied to a beam tube-filter geometry coupled to a simple tumor-patient head model and an improvement of 50% in the dose ratio was obtained
Epithermal BNCT neutron beam design for a TRIGA II reactor
International Nuclear Information System (INIS)
In Finland a collaborative effort by Helsinki University Central Hospital, MAP Medical Technologies Inc. and VTT Reactor Laboratory has started aiming at BNCT of glioma patients. For this the capabilities of the FiR-1 TRIGA II 250 kW research reactor have been evaluated. The FiR-1 is located in the middle of the Otaniemi campus eight kilometers from the center of Helsinki and four kilometers from the Central Hospital. The power of the reactor was increased in 1965 to 250 kW and the instrumentation modernised in 1981. It is a pool reactor with graphite reflector and a core loading of 3 kg 20w% 235U in the special TRIGA uranium-zirconium hydride fuel (8-12 w% U, 91% Zr, 1% H). The advantages of using a TRIGA reactor for BNCT have already been pointed out earlier by Whittemore and have been verified in practice by the thermal neutron treatment work done at the Musashi 100 kW reactor. The advantages include a wide core face area and a wide spatial angle covered by the thermal-epithermal column system, large flux-per-Watt feature and inherent safety of the TRIGA fuel. Because of its wider applicability and less stringent requirements for clinical operation conditions, an epithermal neutron beam has been selected as the design goal. The epithermal flux should be sufficient for glioblastoma patient treatment: 109 epithermal neutrons/cm2/s with low enough fast neutron (-13Gy/epithermal n/cm2) and gamma contamination
Neutron collimator design of neutron radiography based on the BNCT facility
Yang, XP.; Yu, BX; Li, YG; Peng, D; Lu, J.; Zhang, GL.; Zhao, H.; Zhang, AW.; Li, CY.; Liu, WJ; Hu, T.; Lv, JG.
2013-01-01
For the research of CCD neutron radiography, a neutron collimator was designed based on the exit of thermal neutron of the Boron Neutron Capture Therapy (BNCT) reactor. Based on the Geant4 simulations, the preliminary choice of the size of the collimator was determined. The materials were selected according to the literature data. Then, a collimator was constructed and tested on site. The results of experiment and simulation show that the thermal neutron flux at the end of theneutron collimat...
INEL BNCT Research Program annual report 1994
International Nuclear Information System (INIS)
This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory (INEL) Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1994. Contributions from the principal investigators about their individual projects are included, specifically, chemistry (pituitary tumor studies, boron drug development including liposomes, lipoproteins, and carboranylalanine derivatives), pharmacology (murine screenings, toxicity testing, ICP-AES analysis of biological samples), physics (treatment planning software, neutron beam and filter design, neutron beam measurement dosimetry), and radiation biology (small and large animal models tissue studies and efficacy studies). Information on the potential toxicity of BSH and BPA is presented and results of 21 spontaneous tumor bearing dogs that have been treated with BNCT at Brookhaven National Laboratory (BNL) are discussed. Several boron carrying drugs exhibiting good tumor uptake are described. Significant progress in the potential of treating pituitary tumors is presented. Highlights from the First International Workshop on Accelerator-Based Neutron Sources for BNCT are included
BNCT facility development in HANARO
International Nuclear Information System (INIS)
An irradiation facility for boron neutron capture therapy (BNCT) was developed using one of the typical tangential beam tubes in HANARO. Thermal neutron was chosen because of the impossibility of sufficient epithermal neutrons for BNCT at the exit of the beam tube. The facility is designed not only for BNCT study but also for dynamic neutron radiography (DNR) and other experiments requiring pure thermal neutrons. Silicon and bismuth single crystals cooled by liquid nitrogen are selected to filter out fast neutrons and γ-rays and to penetrate the thermal neutrons as much as possible. A water shutter is installed in front of the radiation filter to keep the radiation level low in the irradiation room while it is filled with water. A prompt gamma neutron activation analysis (PGNAA) system was also developed to measure the boron concentration quickly from patient's blood samples. A spare neutron beam from a dedicated beam instrument was diffracted upward using pyrolytic graphite to obtain almost pure thermal neutrons at the target position. (author)
International Nuclear Information System (INIS)
This work reports on the characterisation of a neutron beam shaping assembly (BSA) prototype and on the preliminary modelling of a treatment room for BNCT within the framework of a research programme for the development and construction of an accelerator-based BNCT irradiation facility in Buenos Aires, Argentina. The BSA prototype constructed has been characterised by means of MCNP simulations as well as a set of experimental measurements performed at the Tandar accelerator at the National Atomic Energy Commission of Argentina. - Highlights: ► Characterisation of a neutron beam shaping assembly for accelerator-based BNCT. ► Measurements: total and epi-cadmium neutron fluxes and beam homogeneity. ► Calculations: Monte Carlo simulations with the MCNP code. ► Measured and calculated figure-of-merit parameters in agreement with those of IAEA. ► Initial MCNP dose calculations for a treatment room to define future design actions.
International Nuclear Information System (INIS)
A cavity filter was developed for the SSRF 0-mode beam feedback. The filter is used to pick up the 500 MHz signal from the storage ring beam. The Superfish was used to simulate the model of the cavity bandpass filter. The design method, parameters of the filter and results of beam measurements are described in this paper. (authors)
Neutron collimator design of neutron radiography based on the BNCT facility
Yang, XP; Li, YG; Peng, D; Lu, J; Zhang, GL; Zhao, H; Zhang, AW; Li, CY; Liu, WJ; Hu, T; Lv, JG
2013-01-01
For the research of CCD neutron radiography, a neutron collimator was designed based on the exit of thermal neutron of the Boron Neutron Capture Therapy (BNCT) reactor. Based on the Geant4 simulations, the preliminary choice of the size of the collimator was determined. The materials were selected according to the literature data. Then, a collimator was constructed and tested on site. The results of experiment and simulation show that the thermal neutron flux at the end of theneutron collimator is greater than 10^6 n/cm^2/s, the maximum collimation ratio (L/D) is 58, the Cd-ratio(Mn) is 160 and the diameter of collimator end is 10 cm. This neutron collimator is considered to be applicable for neutron radiography.
Neutron collimator design of neutron radiography based on the BNCT facility
International Nuclear Information System (INIS)
For the research of CCD neutron radiography, a neutron collimator was designed based on the exit of thermal neutron of the Boron Neutron Capture Therapy (BNCT) reactor. Based on the Geant4 simulations, the preliminary choice of the size of the collimator was determined. The materials were selected according to the literature data. Then, a collimator was constructed and tested on site. The results of experiment and simulation show that the thermal neutron flux at the end of the neutron collimator is greater than 1.0×106 n/cm2/s, the maximum collimation ratio (L/D) is 58, the Cd-ratio(Mn) is 160 and the diameter of collimator end is 10 cm. This neutron collimator is considered to be applicable for neutron radiography. (authors)
International Nuclear Information System (INIS)
Highlights: ► The possibility of using natural uranium as a neutron multiplier for D–T neutron generator is examined. ► To optimize output neutron beam, a moderator/filter/reflector arrangement was designed. ► The MCNP4C code has been used for BSA optimization and other simulations. ► The results show that using this system the BNCT in-air recommended parameters are met. - Abstract: Extensive research has recently been carried out for the development of high-energy D–T neutron generators as neutron sources for BNCT. The energy of these high-energy neutrons must be reduced by designing a Beam Shaping Assembly (BSA) to make them usable for BNCT. However, the neutron flux decreases drastically as neutrons pass through different materials of BSA. Therefore, it is very important to find ways to treat the neutrons economically. In this paper the possibility of using natural uranium as a neutron multiplier is investigated in order to increase the number of neutrons emitted from D–T neutron generator. According to the simulations and performed calculations, a sphere containing natural uranium as neutron multiplier was used to increase the number of neutrons generated by the D–T neutron generator. The energy of fast neutrons that are generated by D–T fusion reaction and amplified by neutron multiplier system is decreased using proper materials as moderators and fast neutron filters in BSA. The gamma rays which are generated as a result of neutron interaction with moderators are removed from neutron spectrum using bismuth as the gamma filter. Also, a thermal neutron absorber omits undesired low-energy neutrons which lead to a high radiation dose for the skin and soft tissues. The results show that passing neutrons through such a BSA causes the establishment of free beam parameters yet the reduction of the output beam intensity is unavoidable. The neutron spectrum related to our BSA has a proper epithermal flux and the fast and thermal neutron fluxes are
IRT-Sofia BNCT beam tube optimization study
International Nuclear Information System (INIS)
An optimization study of IRT-Sofia BNCT beam tube is presented. In the study we used the MIT/FCB experience. The enlarging of filter/moderator cross section dimensions and the decreasing of collimator length within the limits of the IRT-Sofia reactor design were analyzed. The influence of beam and reactor core axes non-coincidence on the beam properties was also evaluated. The irradiation resistance of polytetrafluoroethylene (Teflon®) was also evaluated. The results provide information for making decisions on the IRT-Sofia BNCT beam construction.
IRT-Sofia BNCT beam tube optimization study
Energy Technology Data Exchange (ETDEWEB)
Belousov, S., E-mail: belousov@inrne.bas.bg [Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Tsarigradsko 72, Sofia (Bulgaria); Mitev, M.; Ilieva, K. [Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Tsarigradsko 72, Sofia (Bulgaria); Riley, K. [Radiation Monitoring Devices, Watertown, MA (United States); Harling, O. [Nuclear Science and Engineering Department, Massachusetts Institute of Technology, Cambridge, MA (United States)
2011-12-15
An optimization study of IRT-Sofia BNCT beam tube is presented. In the study we used the MIT/FCB experience. The enlarging of filter/moderator cross section dimensions and the decreasing of collimator length within the limits of the IRT-Sofia reactor design were analyzed. The influence of beam and reactor core axes non-coincidence on the beam properties was also evaluated. The irradiation resistance of polytetrafluoroethylene (Teflon{sup Registered-Sign }) was also evaluated. The results provide information for making decisions on the IRT-Sofia BNCT beam construction.
Simplified design of filter circuits
Lenk, John
1999-01-01
Simplified Design of Filter Circuits, the eighth book in this popular series, is a step-by-step guide to designing filters using off-the-shelf ICs. The book starts with the basic operating principles of filters and common applications, then moves on to describe how to design circuits by using and modifying chips available on the market today. Lenk's emphasis is on practical, simplified approaches to solving design problems.Contains practical designs using off-the-shelf ICsStraightforward, no-nonsense approachHighly illustrated with manufacturer's data sheets
Simulation of the BNCT of Brain Tumors Using MCNP Code: Beam Designing and Dose Evaluation
International Nuclear Information System (INIS)
BNCT is an effective method to destroy brain tumoral cells while sparing the healthy tissues. The recommended flux for epithermal neutrons is 109 n/cm2s, which has the most effectiveness on deep-seated tumors. In this paper, it is indicated that using D-T neutron source and optimizing of Beam Shaping Assembly leads to treating brain tumors in a reasonable time where all International Atomic Energy Agency recommended criteria are met. The proposed Beam Shaping Assembly based on a D-T neutron generator consists of a neutron multiplier system, moderators, reflector, and collimator. The simulated Snyder head phantom is used to evaluate dose profiles in tissues due to the irradiation of designed beam. Monte Carlo Code, MCNP-4C, was used in order to perform these calculations. The neutron beam associated with the designed and optimized Beam Shaping Assembly has an adequate epithermal flux at the beam port and neutron and gamma contaminations are removed as much as possible. Moreover, it was showed that increasing J/Φ, as a measure of beam directionality, leads to improvement of beam performance and survival of healthy tissues surrounding the tumor. According to the simulation results, the proposed system based on D-T neutron source, which is suitable for in-hospital installations, satisfies all in-air parameters. Moreover, depth-dose curves investigate proper performance of designed beam in tissues. The results are comparable with the performances of other facilities.
Filter Bank Design for Subband Adaptive Filtering
Haan, Jan Mark de
2001-01-01
Adaptive filtering is an important subject in the field of signal processing and has numerous applications in fields such as speech processing and communications. Examples in speech processing include speech enhancement, echo- and interference- cancellation, and speech coding. Subband filter banks have been introduced in the area of adaptive filtering in order to improve the performance of time domain adaptive filters. The main improvements are faster convergence speed and the reduction of co...
Conceptual design of epithermal neutron beam for BNCT in the thermalizing column of TRIGA reactor
International Nuclear Information System (INIS)
The Monte Carlo feasibility study of development of the epithermal neutron beam for BNCT clinical trials in thermalising column (TC) of TRIGA reactor is presented. The investigation of the possible use of fission converter as well as the set-up of TRIGA reactor core is performed. The optimization of the irradiation facility components is carried out and the configuration with the most favorable cost/performance ratio is proposed. The results prove, that a BNCT irradiation facility with performances, comparable to existing beams throughout the world, could be installed in TC/DC of the TRIGA reactor, quite suitable for the clinical treatments of human patients.(author)
INEL BNCT Research Program annual report 1994
Energy Technology Data Exchange (ETDEWEB)
Venhuizen, J.R. [ed.
1995-11-01
This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory (INEL) Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1994. Contributions from the principal investigators about their individual projects are included, specifically, chemistry (pituitary tumor studies, boron drug development including liposomes, lipoproteins, and carboranylalanine derivatives), pharmacology (murine screenings, toxicity testing, ICP-AES analysis of biological samples), physics (treatment planning software, neutron beam and filter design, neutron beam measurement dosimetry), and radiation biology (small and large animal models tissue studies and efficacy studies). Information on the potential toxicity of BSH and BPA is presented and results of 21 spontaneous tumor bearing dogs that have been treated with BNCT at Brookhaven National Laboratory (BNL) are discussed. Several boron carrying drugs exhibiting good tumor uptake are described. Significant progress in the potential of treating pituitary tumors is presented. Highlights from the First International Workshop on Accelerator-Based Neutron Sources for BNCT are included. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.
Automated Integrated Analog Filter Design Issues
Karolis Kiela; Romualdas Navickas
2015-01-01
An analysis of modern automated integrated analog circuits design methods and their use in integrated filter design is done. Current modern analog circuits automated tools are based on optimization algorithms and/or new circuit generation methods. Most automated integrated filter design methods are only suited to gmC and switched current filter topologies. Here, an algorithm for an active RC integrated filter design is proposed, that can be used in automated filter designs. The algorithm is t...
Design of epithermal neutron beam for clinical BNCT treatment at Slovenian TRIGA research reactor
International Nuclear Information System (INIS)
The Monte Carlo feasibility study of development of epithermal neutron beam for BNCT clinical trials on Jozef Stefan Institute (JSI) TRIGA reactor is presented. The investigation of the possible use of fission converter for the purpose of enhancement of neutron beam, as well as the set-up of TRIGA reactor core is performed. The optimization of the irradiation facility components is carried out and the configuration with the most favorable cost/performance ratio is proposed. The simulation results prove that a BNCT irradiation facility with performances, comparable to existing beams throughout the world, could be installed in the thermalizing column of the TRIGA reactor, quite suitable for the clinical treatments of human patients. (author)
Design of epithermal neutron beam for clinical BNCT treatment at Slovenian TRIGA research reactor
Energy Technology Data Exchange (ETDEWEB)
Maucec, Marko [Jozef Stefan Institute, Reactor Physics Division, Lubljana (Slovenia). E-mail: marko.mauce@ijs.si
1999-07-01
The Monte Carlo feasibility study of development of epithermal neutron beam for BNCT clinical trials on Jozef Stefan Institute (JSI) TRIGA reactor is presented. The investigation of the possible use of fission converter for the purpose of enhancement of neutron beam, as well as the set-up of TRIGA reactor core is performed. The optimization of the irradiation facility components is carried out and the configuration with the most favorable cost/performance ratio is proposed. The simulation results prove that a BNCT irradiation facility with performances, comparable to existing beams throughout the world, could be installed in the thermalizing column of the TRIGA reactor, quite suitable for the clinical treatments of human patients. (author)
Evaluation of D(d,n)3 He reaction neutron source models for BNCT irradiation system design
Institute of Scientific and Technical Information of China (English)
YAO Ze'en; LUO Peng; Tooru KOBAYASHI; Gerard BENGUA
2007-01-01
A mathematical method was developed to calculatc the yield.energy spectrum and angular distribution of neutrons from D(d,n)3 He(D-D)reaction in a thick deuterium-titanium target for incident deuterons in energies lower than 1.0MeV.The data of energy spectrum and angular distribution wefe applied to set up the neutron source model for the beam-shaping-assembly(BSA)design of Boron-Neutron-Capture-Therapy(BNCT)using MCNP-4C code.Three cases of D-D neutron source corresponding to incident deuteron energy of 1000.400 and 150 kaV were investigated.The neutron beam characteristics were compared with the model of a 2.45 MeV mono-energetic and isotropic neutron source using an example BSA designed for BNCT irradiation.The results show significant differences in the neutron beam characteristics,particularly the fast neutron component and fast neutron dose in air,between the non-isotropic neutron source model and the 2.5 MeV mono-energetic and isotropic neutron source model.
HF filter design and computer simulation
Rhea, Randall W
1994-01-01
A book for engineers who design and build filters of all types, including lumped element, coaxial, helical, dielectric resonator, stripline and microstrip types. A thorough review of classic and modern filter design techniques, containing extensive practical design information of passband characteristics, topologies and transformations, component effects and matching. An excellent text for the design and construction of microstrip filters.
International Nuclear Information System (INIS)
The geometry of reactor core, thermal column, collimator and shielding system for BNCT application of TRIGA MARK II Reactor were simulated with MCNP5 code. Neutron particle lethargy and dose were calculated with MCNPX code. Neutron flux in a sample located at the end of collimator after normalized to measured value (Eid Mahmoud Eid Abdel Munem, 2007) at 1 MW power was 1.06 x 108 n/ cm2/ s. According to IAEA (2001) flux of 1.00 x 109 n/ cm2/ s requires three hours of treatment. Few modifications were needed to get higher flux. (Author)
Theory and design of microwave filters
Hunter, Ian
2000-01-01
This is a thorough, graduate-level text which provides a single source for filter design including basic circuit theory, network synthesis and the design of a variety of microwave filter structures. The aim is to present design theories followed by specific examples with numerical simulations of the designs, with pictures of real devices wherever possible. The book is aimed at designers, engineers and researchers working in microwave electronics who need to design or specify filters.
International Nuclear Information System (INIS)
A model of multiple lung metastases in BDIX rats is under study at CNEA (Argentina) to evaluate the feasibility of BNCT for multiple, non-surgically resectable lung metastases. A practical shielding device that comfortably houses a rat, allowing delivery of a therapeutic, uniform dose in lungs while protecting the body from the neutron beam is presented. Based on the final design obtained by numerical simulations, the shield was constructed, experimentally characterized and recently used in the first in vivo experiment at RA-3. - Highlights: • A practical shielding device that comfortably houses a rat is presented. • The shield allows a uniform and useful dose in the rat thoracic area. • A novel computational dosimetry in animals based on Multicell is presented. • Experimental characterization evidences the good performance of the shield. • An irradiation based on a diffuse lung metastases model in rats was performed
Design of a SPECT tomographic image system for online dosimetry in BNCT
International Nuclear Information System (INIS)
We present here a numerical analysis of a projected tomographic image system for online dose measurements in Boron Neutron Capture Therapy. In 94% of neutron capture reactions in boron, the 7Li ion is emitted in an excited state which decays through a characteristic 478 keV prompt gamma ray. In BNCT a large fraction of this radiation escapes from the patient body. Its detection is thus attractive for a noninvasive boron dose measurement and an online absorbed dose evaluation. For this purpose we have proposed a dedicated SPECT (Single Photon Emission Computed Tomography) imaging system. The proposed system can obtain images of 21x21cm2 divided in 1x1cm2 pixels by measuring 20 projections with 41 bins each, with 8% uncertainties in reconstructed dose. (author)
Filter and Filter Bank Design for Image Texture Recognition
Energy Technology Data Exchange (ETDEWEB)
Randen, Trygve
1997-12-31
The relevance of this thesis to energy and environment lies in its application to remote sensing such as for instance sea floor mapping and seismic pattern recognition. The focus is on the design of two-dimensional filters for feature extraction, segmentation, and classification of digital images with textural content. The features are extracted by filtering with a linear filter and estimating the local energy in the filter response. The thesis gives a review covering broadly most previous approaches to texture feature extraction and continues with proposals of some new techniques. 143 refs., 59 figs., 7 tabs.
Active resistance capacitance filter design
Kerwin, W. J.
1970-01-01
Filters, formed by combinations of distributed RC elements with positive-feedback voltage amplifiers, provide transfer functions similar to those the heavier LC filters ordinarily employ. They also provide signal amplification.
Design and construction of electronic filters
International Nuclear Information System (INIS)
The design and construction of very low frequencies electronic filters which will be used for carrying out analysis of pile noise at Mexico's Nuclear Center Triga Mark III Reactor, in order to realize measurements of its parameters is presented. NIM norms and active filters with lineal integrated circuits were used: a. Band pass filter from 10 to 500 hertz, band width 50. b. Low pass filter from 0.001 to 10 hertz in 3 steps. c. Kalman Bucy filter, an analogical simulation of this filter was undertaken, obtained from a mathematical model of a Zero power experimental reactor, with the purpose to establish a control searching. (author)
INEL BNCT Research Program annual report, 1992
Energy Technology Data Exchange (ETDEWEB)
Venhuizen, J.R. [ed.
1993-05-01
This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1992. Contributions from all the principal investigators about their individual projects are included, specifically, chemistry (pituitary tumor targeting compounds, boron drug development including liposomes, lipoproteins, and carboranylalanine derivatives), pharmacology (murine screenings, toxicity testing, inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis of biological samples), physics (radiation dosimetry software, neutron beam and filter design, neutron beam measurement dosimetry), and radiation biology (small and large animal models tissue studies and efficacy studies). Information on the potential toxicity of borocaptate sodium and boronophenylalanine is presented, results of 21 spontaneous-tumor-bearing dogs that have been treated with BNCT at the Brookhaven National Laboratory (BNL) Medical Research Reactor (BMRR) are discussed, and predictions for an epithermal-neutron beam at the Georgia Tech Research Reactor (GTRR) are shown. Cellular-level boron detection and localization by secondary ion mass spectrometry, sputter-initiated resonance ionization spectroscopy, low atomization resonance ionization spectroscopy, and alpha track are presented. Boron detection by ICP-AES is discussed in detail. Several boron carrying drugs exhibiting good tumor uptake are described. Significant progress in the potential of treating pituitary tumors with BNCT is presented. Measurement of the epithermal-neutron flux at BNL and comparison to predictions are shown. Calculations comparing the GTRR and BMRR epithermal-neutron beams are also presented. Individual progress reports described herein are separately abstracted and indexed for the database.
INEL BNCT Research Program annual report, 1992
International Nuclear Information System (INIS)
This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1992. Contributions from all the principal investigators about their individual projects are included, specifically, chemistry (pituitary tumor targeting compounds, boron drug development including liposomes, lipoproteins, and carboranylalanine derivatives), pharmacology (murine screenings, toxicity testing, inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis of biological samples), physics (radiation dosimetry software, neutron beam and filter design, neutron beam measurement dosimetry), and radiation biology (small and large animal models tissue studies and efficacy studies). Information on the potential toxicity of borocaptate sodium and boronophenylalanine is presented, results of 21 spontaneous-tumor-bearing dogs that have been treated with BNCT at the Brookhaven National Laboratory (BNL) Medical Research Reactor (BMRR) are discussed, and predictions for an epithermal-neutron beam at the Georgia Tech Research Reactor (GTRR) are shown. Cellular-level boron detection and localization by secondary ion mass spectrometry, sputter-initiated resonance ionization spectroscopy, low atomization resonance ionization spectroscopy, and alpha track are presented. Boron detection by ICP-AES is discussed in detail. Several boron carrying drugs exhibiting good tumor uptake are described. Significant progress in the potential of treating pituitary tumors with BNCT is presented. Measurement of the epithermal-neutron flux at BNL and comparison to predictions are shown. Calculations comparing the GTRR and BMRR epithermal-neutron beams are also presented. Individual progress reports described herein are separately abstracted and indexed for the database
Satisfactory Optimization Design of IIR Digital Filters
Institute of Scientific and Technical Information of China (English)
Jin Weidong; Zhang Gexiang; Zhao Duo
2005-01-01
A new method called satisfactory optimization method is proposed to design IIR (Infinite Impulse Response) digital filters, and the satisfactory optimization model is presented. The detailed algorithm of designing IIR digital filters using satisfactory optimization method is described. By using quantum genetic algorithm characterized by rapid convergence and good global search capability, the satisfying solutions are achieved in the experiment of designing lowpass and bandpass IIR digital filters. Experimental results show that the performances of IIR filters designed by the introduced method are better than those by traditional methods.
FPGA design and implementation of Gaussian filter
Yang, Zhihui; Zhou, Gang
2015-12-01
In this paper , we choose four different variances of 1,3,6 and 12 to conduct FPGA design with three kinds of Gaussian filtering algorithm ,they are implementing Gaussian filter with a Gaussian filter template, Gaussian filter approximation with mean filtering and Gaussian filter approximation with IIR filtering. By waveform simulation and synthesis, we get the processing results on the experimental image and the consumption of FPGA resources of the three methods. We set the result of Gaussian filter used in matlab as standard to get the result error. By comparing the FPGA resources and the error of FPGA implementation methods, we get the best FPGA design to achieve a Gaussian filter. Conclusions can be drawn based on the results we have already got. When the variance is small, the FPGA resources is enough for the algorithm to implement Gaussian filter with a Gaussian filter template which is the best choice. But when the variance is so large that there is no more FPGA resources, we can chose the mean to approximate Gaussian filter with IIR filtering.
Design Procedure for Compact Folded Waveguide Filters
DEFF Research Database (Denmark)
Dong, Yunfeng; Johansen, Tom Keinicke; Zhurbenko, Vitaliy;
Waveguide filters are widely used in communication systems due to low losses and high power handling capabilities. One drawback of the conventional waveguide filters is their large size, especially for low-frequency and high-order realizations. It has been shown that the footprint of conventional...... waveguide resonators can be reduced to one quarter by folding the electric and magnetic fields inside the cavity (J. S. Hong, Microwave Symposium Digest, 2004, Vol. 1, pp. 213-216). This paper presents a novel systematic procedure for designing compact low-loss bandpass filters by using folded waveguide...... resonators. As a design example, a scaled version of a filter specified for a TETRA (Terrestrial Trunked Radio) system has been considered. The folded waveguide filter is designed to fulfil specific requirements, and the design procedure can be easily applied to other folded waveguide filter designs...
Performance analysis and design of filtering hydrocyclones
Directory of Open Access Journals (Sweden)
L. G. M. Vieira
2005-03-01
Full Text Available The filtering hydrocyclone is a solid-liquid separation device patented by the Chemical Engineering Department at the Federal University of Uberlândia, which consists of a hydrocyclone whose conical section was replaced by a conical filtering wall. The objective of this work is to compare the performances of the filtering hydrocyclones designed by Bradley and by Rietema. The experimental results obtained with the filtering hydrocyclones under the same operational conditions as those used with the conventional device allow the conclusion that performance of the Bradley and Rietema types is significantly influenced by the filtering medium. Rietema's filtering hydrocyclones had a lower volumetric feed flowrate than the conventional device and Bradley's filtering hydrocyclones showed increases in this same variable. In both designs, overall efficiency was influenced by the underflow-to-throughput ratio.
Design of energy filters for electron microscopes
Tsuno, Katsushige
1999-11-01
Software for simulating 3D electric and magnetic fields followed by the direct ray tracing in individual field and combined fields (EO3D, MO3D and CO3D) are well applied to the design of energy filters attached to electron microscopes. When we had designed a high resolution EELS instrument, we had no 3D software, and encountered problems in designing a retarding Wien filter used as the monochromator and analyzer. At that time, electric field homogeneity inside the gap of magnet and the deflection of beam at the fringing region due to the deviation of the Wien condition were unsolved problems. When we designed a low energy reflection electron microscope (LEEM), we had 3D software, and some of the above problems were solved. We used an arc shaped electrode for the beam separator and an eight-pole filter for the analyzer. The coincidence of the magnetic and electric fringing field distributions at the fringing regions (Wien condition) was not perfect but was improved. We have designed an omega filter for in-column energy filtered transmission electron microscope (EFTEM). The omega filter consists of four sector magnets. Optical behavior of the system is very complicated. First, we designed the filter by 2D approximation and then checked by electron trajectories by the 3D software. The designed omega filter works successfully.
Digital filter design for radar image formation
Adams, John W.; Nelson, Jeffrey E.; Banh, N. D.; Moncada, John J.; Bayma, Robert W.
1989-01-01
Novel weighted-least-squares approaches to the design of digital filters for SAR applications are presented. The filters belong to three different categories according to their combinations of minimax passband, least-squares stopband, minimax stopband, and maximally-flat passband. For real-time applications, it is important to design the sets of digital filter coefficient tables in an offline environment; the appropriate precomputed filter is then selected for each SAR signal-processing function, as a function of both mode and mapping geometry during real-time processing.
Analog Electronic Filters Theory, Design and Synthesis
Dimopoulos, Hercules G
2012-01-01
Filters are essential subsystems in a huge variety of electronic systems. Filter applications are innumerable; they are used for noise reduction, demodulation, signal detection, multiplexing, sampling, sound and speech processing, transmission line equalization and image processing, to name just a few. In practice, no electronic system can exist without filters. They can be found in everything from power supplies to mobile phones and hard disk drives and from loudspeakers and MP3 players to home cinema systems and broadband Internet connections. This textbook introduces basic concepts and methods and the associated mathematical and computational tools employed in electronic filter theory, synthesis and design. This book can be used as an integral part of undergraduate courses on analog electronic filters. Includes numerous, solved examples, applied examples and exercises for each chapter. Includes detailed coverage of active and passive filters in an independent but correlated manner. Emphasizes real filter...
Design of New SAW DQPSK Matched Filter
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
A new surface acoustic wave differential quadraphase shift key(SAW DQPSK) spread spectrum(SS) signal matched filter based on the fusion of SS and differential modulation is reported. The design of multi-phase coded SAW matched filter is proposed rather than another design of SAW DQPSK filter, which can cut in a half of the delay time of SAW DQPSK matched filter and SAW fixed delay line(FDL) used for differential demodulation. This breakthrough is made the system largely reduce a size and process much easily. This method can also be feasible in other SAW MPSK matched filter design especially when the modulation phase number is larger than 4. The design example and its experimental results are given.
Design of Kalman filters for mobile robots
DEFF Research Database (Denmark)
Larsen, Thomas Dall; Hansen, Karsten L.; Andersen, Nils Axel;
1999-01-01
Kalman filters have for a long time been widely used on mobile robots as a location estimator. Many different Kalman filter designs have been proposed, using models of various complexity. In this paper, two different design methods are evaluated and compared. Focus is put on the common setup where...... the mobile robot is equipped with a dual encoder system supported by some additional absolute measurements. A common filter type for this setup is the odometric filter, where readings from the odometry system on the robot are used together with the geometry of the robot movement as a model of the robot....... If additional kinematic assumptions are made, for instance regarding the velocity of the robot, an augmented model can be used instead. This kinematic filter has some advantages when used intelligently, and it is shown how this type of filter can be used to suppress noise on encoder readings and velocity...
Preliminary modeling of BNCT beam tube on IRT in Sofia
Energy Technology Data Exchange (ETDEWEB)
Belousov, S. [Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Tsarigradsko 72, Sofia (Bulgaria)], E-mail: belousov@inrne.bas.bg; Ilieva, K. [Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Tsarigradsko 72, Sofia (Bulgaria)
2009-07-15
The technical design of the research reactor IRT in Sofia is in progress. It includes an arrangement for a BNCT facility for tumor treatment. Modeling of geometry and material composition of filter/collimator for the BNCT beam tube on IRT has been carried out following the beam tube configuration of the Massachusetts Institute of Technology Reactor [Harling et al., 2002. The fission converter-based epithermal neutron irradiation facility at the Massachusetts Institute of Technology Reactor. Nucl. Sci. Eng. 140, 223-240.] and taking into account an ability to include the tube into the IRT reactor geometry. The results of neutron and gamma transport calculations performed for the model have shown that the facility will be able to supply an epithermal neutron flux of about 5x10{sup 9} n cm{sup -2} s{sup -1}, with low contamination from fast neutrons and gamma rays that would be among the best facilities currently available. An optimiziation study has been performed for the beam collimator, following similar studies for the TAPIRO research reactor in Italy. [Nava et al., 2005. Monte Carlo optimization of a BNCT facility for treating brain gliomas at the TAPIRO reactor. Radiat. Prot. Dosim. 116 (1-4), 475-481.].
Preliminary modeling of BNCT beam tube on IRT in Sofia
International Nuclear Information System (INIS)
The technical design of the research reactor IRT in Sofia is in progress. It includes an arrangement for a BNCT facility for tumor treatment. Modeling of geometry and material composition of filter/collimator for the BNCT beam tube on IRT has been carried out following the beam tube configuration of the Massachusetts Institute of Technology Reactor [Harling et al., 2002. The fission converter-based epithermal neutron irradiation facility at the Massachusetts Institute of Technology Reactor. Nucl. Sci. Eng. 140, 223-240.] and taking into account an ability to include the tube into the IRT reactor geometry. The results of neutron and gamma transport calculations performed for the model have shown that the facility will be able to supply an epithermal neutron flux of about 5x109 n cm-2 s-1, with low contamination from fast neutrons and gamma rays that would be among the best facilities currently available. An optimiziation study has been performed for the beam collimator, following similar studies for the TAPIRO research reactor in Italy. [Nava et al., 2005. Monte Carlo optimization of a BNCT facility for treating brain gliomas at the TAPIRO reactor. Radiat. Prot. Dosim. 116 (1-4), 475-481.
BNCT activities at Slovenian TRIGA research reactor
International Nuclear Information System (INIS)
It has been reported that satisfactory thermal/epithermal neutron beams for Boron Neutron Capture Therapy (BNCT) could be designed at TRIGA research reactors These reactors are generally perceived as being safe to install and operate in populated areas. This contribution presents the most recent BNCT research activities on the 'Jozef Stefan' Institute, where epithermal neutron beam for 'in-vitro' irradiation has been developed and experimentally verified. Furthermore, The Monte Carlo feasibility study of development of the epithermal neutron beam for BNCT clinical trials of human patients in thermalising column (TC) of TRIGA reactor has been carried out. The simulation results prove, that a BNCT irradiation facility with performances, comparable to existing beam throughout the world, could be installed in TC of the TRIGA reactor. (author)
Ridge filter design for carbon radiotherapy
International Nuclear Information System (INIS)
The design of a ridge filter intended for forming the uniform spread-out Bragg peak within a tumor at carbon radiotherapy is described. The computation of the ridge filter shape was carried out by an analytical algorithm and tested by MC simulation (GEANT4 code). Two kinds of the ridge filter were considered: stationary and movable. The influence on a ridge filter shape of the carbon beam energy and type of relative biological effectiveness dependence on the carbon ion linear energy transfer in tissue were examined
Moisture reduction of filter cake by improved filter design
Energy Technology Data Exchange (ETDEWEB)
Dahlstrom, D.A.; Davis, S.S.; Garlick, L.D.
1983-10-01
With the redesign of the Agidisc filter, several improvements have been achieved as follows: Internal velocities of filtrate and air have been greatly reduced in the PIPPED sectors, ferrules, internal channels and filter valve. This will maximize pressure drop across the cake resulting in lower moistures and decreased wear. The PIPPED sector achieves better cake discharge because of the flexing action while increasing bag life. Moisture content reduction for the PIPPED sectors alone appear to have the potential for about 1 1/2 percentage points lower then redwood sectors. By indexing the two halves of the disc filter so each half discharges separately, shock wear on the cake conveyor should be reduced. More air volume will also go to less sectors resulting in better discharge. Using a sudden blow with a low pressure blower for cake discharge, energy consumption is reduced. Overall maintenance costs for the new design should be reduced through less wear due to appreciably reduced velocities.
Design rules for dislocation filters
International Nuclear Information System (INIS)
The efficacy of strained layer threading dislocation filter structures in single crystal epitaxial layers is evaluated using numerical modeling for (001) face-centred cubic materials, such as GaAs or Si1−xGex, and (0001) hexagonal materials such as GaN. We find that threading dislocation densities decay exponentially as a function of the strain relieved, irrespective of the fraction of threading dislocations that are mobile. Reactions between threading dislocations tend to produce a population that is a balanced mixture of mobile and sessile in (001) cubic materials. In contrast, mobile threading dislocations tend to be lost very rapidly in (0001) GaN, often with little or no reduction in the immobile dislocation density. The capture radius for threading dislocation interactions is estimated to be approximately 40 nm using cross section transmission electron microscopy of dislocation filtering structures in GaAs monolithically grown on Si. We find that the minimum threading dislocation density that can be obtained in any given structure is likely to be limited by kinetic effects to approximately 104–105 cm−2
Design rules for dislocation filters
Energy Technology Data Exchange (ETDEWEB)
Ward, T.; Sánchez, A. M.; Beanland, R., E-mail: r.beanland@warwick.ac.uk [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Tang, M.; Wu, J.; Liu, H. [Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom); Dunstan, D. J. [School of Physics and Astronomy, Queen Mary University of London, London E1 4NS (United Kingdom)
2014-08-14
The efficacy of strained layer threading dislocation filter structures in single crystal epitaxial layers is evaluated using numerical modeling for (001) face-centred cubic materials, such as GaAs or Si{sub 1−x}Ge{sub x}, and (0001) hexagonal materials such as GaN. We find that threading dislocation densities decay exponentially as a function of the strain relieved, irrespective of the fraction of threading dislocations that are mobile. Reactions between threading dislocations tend to produce a population that is a balanced mixture of mobile and sessile in (001) cubic materials. In contrast, mobile threading dislocations tend to be lost very rapidly in (0001) GaN, often with little or no reduction in the immobile dislocation density. The capture radius for threading dislocation interactions is estimated to be approximately 40 nm using cross section transmission electron microscopy of dislocation filtering structures in GaAs monolithically grown on Si. We find that the minimum threading dislocation density that can be obtained in any given structure is likely to be limited by kinetic effects to approximately 10{sup 4}–10{sup 5 }cm{sup −2}.
Polychromator filter design with genetic algorithm
International Nuclear Information System (INIS)
In Thomson scattering (TS) diagnostics, polychromators are equipped with several optical band-pass filters which cover the spectral region where the radiation from the incident laser beam is expected to be Doppler shifted. The spectral location of the transmission band of individual filters has a strong influence on the measured electron temperature (Te) since the latter is derived from a previously computed lookup table including the spectral specifications of the filters. Here, we present the design of the set of polychromator filters through genetic algorithms (GAs). We examine the developed algorithm under two specific target conditions, and optimized filter sets covering the wavelength region longer than the wavelength of the incident laser seem to be more effective in improving the accuracy of the Te calculations provided by the diagnostic. (paper)
Design of withdrawal-weighted SAW filters.
Lee, Youngjin; Lee, Seunghee; Roh, Yongrae
2002-03-01
This paper presents a new design algorithm for a withdrawal-weighted surface acoustic wave (SAW) transversal filter. The proposed algorithm is based on the effective transmission loss theory and a delta function model of a SAW transversal filter. The design process consists of three steps, which eventually determine eight geometrical design parameters for the filter in order to satisfy given performance specifications. First, the number of fingers in the input and output interdigital transducers (IDTs), plus their geometrical sizes is determined using the insertion loss specification. Second, the number and positions of the polarity reverses in the output IDT are determined using the bandwidth and ripple specifications. Third, the number and position for withdrawing and switching specific fingers in the output IDT and attached electrode area are determined to achieve the desired sidelobe level. The efficiency of the technique is illustrated using a sample design of an IF filter consisting of a uniform input IDT and withdrawal-weighted output IDT. The proposed algorithm is distinct from conventional techniques in that it can optimize the structural geometry of a withdrawal-weighted SAW filter in a direct manner by considering all the performance specifications simultaneously. PMID:12322883
International Nuclear Information System (INIS)
Quenching the anion generated from a 2-(ω-carboranylalkyl)dithiane with 2H2O at -78oC and at 0oC introduced deuterium exclusively at C-2 of the carborane. Extension of this model reaction to a bioreductively-targetted carborane allowed the synthesis of 2-[2H]- and 2-[3H]-isotopomers of a nitroimidazole-carborane which is of interest in boron neutron capture therapy (BNCT) of cancer. (author)
International Nuclear Information System (INIS)
The activity in accelerator development for accelerator-based BNCT (AB-BNCT) both worldwide and in Argentina is described. Projects in Russia, UK, Italy, Japan, Israel, and Argentina to develop AB-BNCT around different types of accelerators are briefly presented. In particular, the present status and recent progress of the Argentine project will be reviewed. The topics will cover: intense ion sources, accelerator tubes, transport of intense beams, beam diagnostics, the 9Be(d,n) reaction as a possible neutron source, Beam Shaping Assemblies (BSA), a treatment room, and treatment planning in realistic cases. - Highlights: • The activity in accelerator development for accelerator-based BNCT (AB-BNCT) both worldwide and in Argentina is described. • Projects in Russia, UK, Italy, Japan, Israel, and Argentina to develop AB-BNCT around different types of accelerators are briefly presented. • The present status and recent progress of the Argentine project will be reviewed. • Topics cover intense ion sources, accelerator tubes, transport of intense beams and beam diagnostics, among others
BNCT with linac, feasibility study
International Nuclear Information System (INIS)
High energy photon beams from Medical Linear Accelerators (linacs) which are used in radiotherapy produce undesirable neutrons, beside the clinically useful electron and photon beams. Neutrons are produced from the photonuclear reaction (γ,n) of high energy photons with high Z-materials which compose the accelerator head. In this paper the possible use of these undesirable neutrons for BNCT is investigated, making use of high energy linacs already installed in hospitals, primarily for high energy electron and photon therapy and applying them in the context of BNCT. The photoneutron components emitted by the accelerator is the source for Monte Carlo simulations of the interactions that take place within the head of a voxel-based phantom. The neutron flux across the phantom head is calculated using different moderator arrangements and different techniques in the aim of increasing the thermal neutron flux at the targeted site. Also, we shall test different configurations of the linac head to maximize the exposure of high-Z materials to the photon beam, including the removal of the flattening filter, so as to boost the photoneutron production in the linac head. Experimental work will be conducted in hospitals to validate the Monte Carlo simulations. To make use of linacs for BNCT will be advantageous in the sense that the setting in a hospital department is much more acceptable by the public than a reactor installation. This will mean less complications regarding patient positioning and movement with respect to the beams, additional patient transportation and management will be more cost effective. (author)
High neutronic efficiency, low current targets for accelerator-based BNCT applications
International Nuclear Information System (INIS)
The neutronic efficiency of target/filters for accelerator-based BNCT applications is measured by the proton current required to achieve a desirable neutron current at the treatment port (109 n/cm2/s). In this paper the authors describe two possible targeyt/filter concepts wihch minimize the required current. Both concepts are based on the Li-7 (p,n)Be-7 reaction. Targets that operate near the threshold energy generate neutrons that are close tothe desired energy for BNCT treatment. Thus, the filter can be extremely thin (∼ 5 cm iron). However, this approach has an extremely low neutron yield (n/p ∼ 1.0(-6)), thus requiring a high proton current. The proposed solutino is to design a target consisting of multiple extremely thin targets (proton energy loss per target ∼ 10 keV), and re-accelerate the protons between each target. Targets operating at ihgher proton energies (∼ 2.5 MeV) have a much higher yield (n/p ∼ 1.0(-4)). However, at these energies the maximum neutron energy is approximately 800 keV, and thus a neutron filter is required to degrade the average neutron energy to the range of interest for BNCT (10--20 keV). A neutron filter consisting of fluorine compounds and iron has been investigated for this case. Typically a proton current of approximately 5 mA is required to generate the desired neutron current at the treatment port. The efficiency of these filter designs can be further increased by incorporating neutron reflectors that are co-axial with the neutron source. These reflectors are made of materials which have high scattering cross sections in the range 0.1--1.0 MeV
A Novel Filter Bank Design Method with CEM FRM Technique
Li-Zhi Zhang; Wen-Yu Luo
2009-01-01
Modulation filter banks can be obtained by modulating one or two prototype filters, which reduce the design complexity of the filter banks. Furthermore, this kind of filter can be realized by using DFT or FFT with very high computationally efficiency. The proposition of a modulation filter bank reduces the computation complexity of designing the filter bank consumedly, which has very high computation efficiency. However, with the increasing of channels, the request for transition of the proto...
Design of spectral filtering for tissue classification
Narayanan, Ajay; Shah, Pratik; Das, Bipul
2012-02-01
Tissue characterization from imaging studies is an integral part of clinical practice. We describe a spectral filter design for tissue separation in dual energy CT scans obtained from Gemstone Spectral Imaging scanner. It enables to have better 2D/3D visualization and tissue characterization in normal and pathological conditions. The major challenge to classify tissues in conventional computed tomography (CT) is the x-ray attenuation proximity of multiple tissues at any given energy. The proposed method analyzes the monochromatic images at different energy levels, which are derived from the two scans obtained at low and high KVp through fast switching. Although materials have a distinct attenuation profile across different energies, tissue separation is not trivial as tissues are a mixture of different materials with range of densities that vary across subjects. To address this problem, we define spectral filtering, that generates probability maps for each tissue in multi-energy space. The filter design incorporates variations in the tissue due to composition, density of individual constituents and their mixing proportions. In addition, it also provides a framework to incorporate zero mean Gaussian noise. We demonstrate the application of spectral filtering for bone-free vascular visualization and calcification characterization.
BNCT. Computational Analysis; BNCT. Analisis computacional
Energy Technology Data Exchange (ETDEWEB)
Caro, R.
2004-07-01
The BNCT (Boron Neutron Capture Therapy) is a new oncologic radiotherapy technique in the process of research which consists of injecting a non-poisonous pharmacovector into an ill patient in such a way that the tumor receives isotope boron-10, so that the tumoral area can later be bombarded with a beam of neutrons, many of which are captured the isotope in question. (Author)
Design and application of finite impulse response digital filters
International Nuclear Information System (INIS)
The finite impulse response (FIR) digital filter is a spatial domain filter with a frequency domain representation. The theory of the FIR filter is presented and techniques are described for designing FIR filters with known frequency response characteristics. Rational design principles are emphasized based on characterization of the imaging system using the modulation transfer function and physical properties of the imaged objects. Bandpass, Wiener, and low-pass filters were designed and applied to 201Tl myocardial images. The bandpass filter eliminates low-frequency image components that represent background activity and high-frequency components due to noise. The Wiener, or minimum mean square error filter 'sharpens' the image while also reducing noise. The Wiener filter illustrates the power of the FIR technique to design filters with any desired frequency reponse. The low-pass filter, while of relative limited use, is presented to compare it with a popular elementary 'smoothing' filter. (orig.)
Design of Microwave Multibandpass Filters with Quasilumped Resonators
Dejan Miljanović; Milka Potrebić; Tošić, Dejan V.
2015-01-01
Design of RF and microwave filters has always been the challenging engineering field. Modern filter design techniques involve the use of the three-dimensional electromagnetic (3D EM) solvers for predicting filter behavior, yielding the most accurate filter characteristics. However, the 3D EM simulations are time consuming. In this paper, we propose electric-circuit models, instead of 3D EM models, suitable for design of RF and microwave filters with quasilumped coupled resonators. Using the d...
American brain tumor patients treated with BNCT in Japan
International Nuclear Information System (INIS)
The purpose of this work is to establish and maintain a database for patients from the United States who have received BNCT in Japan for malignant gliomas of the brain. This database will serve as a resource for the DOE to aid in decisions relating to BNCT research in the United States, as well as assisting the design and implementation of clinical trials of BNCT for brain cancer patients in this country. The database will also serve as an information resource for patients with brain tumors and their families who are considering this form of therapy
American brain tumor patients treated with BNCT in Japan
Energy Technology Data Exchange (ETDEWEB)
Laramore, G.E.; Griffin, B.R.; Spence, A.
1995-11-01
The purpose of this work is to establish and maintain a database for patients from the United States who have received BNCT in Japan for malignant gliomas of the brain. This database will serve as a resource for the DOE to aid in decisions relating to BNCT research in the United States, as well as assisting the design and implementation of clinical trials of BNCT for brain cancer patients in this country. The database will also serve as an information resource for patients with brain tumors and their families who are considering this form of therapy.
Dose estimation of the THOR BNCT treatment room
International Nuclear Information System (INIS)
BNCT beam of Tsing Hua Open-pool Reactor (THOR) was designed and constructed since 1998. A treatment room for the newly modified THOR BNCT beam was constructed for the next clinical-stage trials in 2004. Dose distribution in a patient (or a phantom) is important as irradiated with the BNCT beam. The dose distributions for different type of radiations such as neutron and photons in the treatment room are strongly becoming the index or reference of success for a BNCT facility. An ART head phantom was placed in front of the THOR BNCT beam port and was irradiated. In each section of the head phantom, numbers of small holes are inside and separated uniformly. Dual detector: TLD-600 and TLD-700 chips were placed inside these holes within the phantom to distinct doses of neutron and photon. Besides, Dual-TLD chips were latticed placed in the horizontal plane of beam central axis, in the treatment room to estimate the spatial dose distribution of neutron and photon. Gold foils were assisted in TLD dose calibrations. Neutron and photon dose distributions in phantom and spatial dose distributions in the THOR BNCT treatment room were both estimated in this work. Testing and improvement in THOR BNCT beam were continuative during these years. Results of this work could be the reference and be helpful for the further clinical trials in nearly future. (author)
Energy Technology Data Exchange (ETDEWEB)
Ackermann, A.L. (ed.)
1991-08-01
This Bulletin presents a summary of accomplishments and highlights in the Idaho National Engineering Laboratory's (INEL) Boron Neutron Capture Therapy (BNCT) Program for August 1991. This bulletin includes information on the brain tumor and melanoma research programs, Power Burst Facility (PBF) technical support and modifications, PBF operations, and updates to the animal data charts.
BNCT-RTPE: BNCT radiation treatment planning environment
Energy Technology Data Exchange (ETDEWEB)
Wessol, D.E.; Wheeler, F.J. [Idaho National Engineering Lab., Idaho Fall, ID (United States); Babcock, R.S. [and others
1995-11-01
Several improvements have been developed for the BNCT radiation treatment planning environment (BNCT-Rtpe) during 1994. These improvements have been incorporated into Version 1.0 of BNCT-Rtpe which is currently installed at the INEL, BNL, Japanese Research Center (JRC), and Finland`s Technical Research Center. Platforms supported by this software include Hewlett-Packard (HP), SUN, International Business Machines (IBM), and Silicon Graphics Incorporated (SGI). A draft version of the BNCT-Rtpe user manual is available. Version 1.1 of BNCT-Rtpe is scheduled for release in March 1995. It is anticipated that Version 2.x of BNCT-Rtpe, which includes the nonproprietary NURBS library and data structures, will be released in September 1995.
New EORTC clinical trials for BNCT
International Nuclear Information System (INIS)
Due to ethical reasons, a separated optimization of the two components of BNCT in the frame of clinical investigations can only be performed applying the whole binary system. The ongoing trial at HFR (High Flux Reactor Petten) has proven the feasibility of BNCT under defined conditions. On that basis the European Commission supported a comprehensive research project on boron imaging including three further clinical studies. In the first trial the boron uptake related to the blood boron concentration and surrounding normal tissue in various solid tumours will be examined using BSH (Sodiumborocaptate), BPA (Boronophenylalanine) or both in order to explore tumour entities, which may gain benefit from BNCT. The major objectives of the second trial are to define the maximum tolerated single and cumulative dose, and the dose limiting toxicity of BSH. The third clinical trial, a phase II study is designed to evaluate the anti-tumour effect of fractionated BNCT at the Petten treatment facility against cerebral metastasis of malignant melanoma using BPA. (author)
Optimization of the irradiation beam in the BNCT research facility at IEA-R1 reactor
International Nuclear Information System (INIS)
Boron Neutron Capture Therapy (BNCT) is a radiotherapeutic technique for the treatment of some types of cancer whose useful energy comes from a nuclear reaction that occurs when thermal neutron impinges upon a Boron-10 atom. In Brazil there is a research facility built along the beam hole number 3 of the IEA-R1 research reactor at IPEN, which was designed to perform BNCT research experiments. For a good performance of the technique, the irradiation beam should be mostly composed of thermal neutrons with a minimum as possible gamma and above thermal neutron components. This work aims to monitor and evaluate the irradiation beam on the sample irradiation position through the use of activation detectors (activation foils) and also to propose, through simulation using the radiation transport code, MCNP, new sets of moderators and filters which shall deliver better irradiation fields at the irradiation sample position In this work, a simulation methodology, based on a MCNP card, known as wwg (weight window generation) was studied, and the neutron energy spectrum has been experimentally discriminated at 5 energy ranges by using a new set o activation foils. It also has been concluded that the BNCT research facility has the required thermal neutron flux to perform studies in the area and it has a great potential for improvement for tailoring the irradiation field. (author)
Design of high frequency integrated analogue filters
Sun, Yichuang
2002-01-01
This book brings together leading researchers to highlight recent advances and identify promising directions for future development. Motivated by the market for mobile and wireless communications, fully integrated analog filters for high-frequency applications are now receiving great interest world-wide. Chapters are dedicated to MOSFET-C and Gm-C filters, current-mode continuous-time filters, log-domain filters, switched-current filters, adaptive filters and on-chip automatic tuning. The topical nature of the book and caliber of the authors ensures that this book will be of wide interest to t
Design of LCL-Filter Based Three-level Active Power Filter
Directory of Open Access Journals (Sweden)
Shilan Chen
2013-07-01
Full Text Available This paper proposes an improved design of LCL-Filters for Three-Level Shunt Active power filters (APF. Available design principles are presented to achieve high compensation bandwidth and low switching frequency current. Then, affecitons of different parameters are taken into consideration of constraints on LCL-Filter design with detail analysis of ripple current. A simple and practical design procedure of LCL-Filter for Three-Level APF is subsequently proposed. The first step is to choose the resonant frequency of LCL-Filter according to the highest order harmonic needed to be compensated. Then it is aim to optimize the parameters of the LCL-Filter based on the design principles and constraints. The simulation results verify the effectiveness of the proposed method.
International Nuclear Information System (INIS)
As part of the joint project on extra-corporal treatment of liver cancer by BNCT between JRC Petten and the University Hospital Essen, a facility has been designed and built to contain the liver during its irradiation treatment at the HFR Petten. The design consists of a rotating spheroid shaped PMMA holder, manufactured to open at the equator and closed by screwing together, surrounded by PMMA and graphite blocks. A validation exercise has been performed regarding both the nuclear conditions and the physical conditions. For the former, activation foil sets of Au, Cu and Mn, were irradiated at positions inside the liver holder filled with water, whilst a second measurement campaign has been performed using gel dosimetry. For the physical test, it is required to operate (rotate) the facility for up to 4 hours and to maintain the liver at approximately 4degC. The latter test was performed using 'cold gun sprays' that inject cold air near the liver holder. Both the nuclear and physical validation tests were performed successfully. (author)
Researches on Parameters Calculation of Designing Double-tuned Filter
HE Yi-hong; Su, Heng
2013-01-01
Aiming at the question of parameter of double-tuned filter, A new method of designing double-tuned filter was proposed based on resonance frequency, by using the relationship that the impedance of double-tund filter and two parallel single tuned filters is equal and the resonance frequency of single tuned filter is the zero of the impedance of double-tuned filter. A simulation was established to prove the correctness of this method by using the software MATLAB in a power system. Simulation r...
An Accelerator Neutron Source for BNCT
International Nuclear Information System (INIS)
The overall goal of this project was to develop an accelerator-based neutron source (ABNS) for Boron Neutron Capture Therapy (BNCT). Specifically, our goals were to design, and confirm by measurement, a target assembly and a moderator assembly that would fulfill the design requirements of the ABNS. These design requirements were (1) that the neutron field quality be as good as the neutron field quality for the reactor-based neutron sources for BNCT, (2) that the patient treatment time be reasonable, (3) that the proton current required to treat patients in reasonable times be technologically achievable at reasonable cost with good reliability, and accelerator space requirements which can be met in a hospital, and finally (4) that the treatment be safe for the patients
An Accelerator Neutron Source for BNCT
Energy Technology Data Exchange (ETDEWEB)
Blue, Thomas, E
2006-03-14
The overall goal of this project was to develop an accelerator-based neutron source (ABNS) for Boron Neutron Capture Therapy (BNCT). Specifically, our goals were to design, and confirm by measurement, a target assembly and a moderator assembly that would fulfill the design requirements of the ABNS. These design requirements were 1) that the neutron field quality be as good as the neutron field quality for the reactor-based neutron sources for BNCT, 2) that the patient treatment time be reasonable, 3) that the proton current required to treat patients in reasonable times be technologially achievable at reasonable cost with good reliability, and accelerator space requirements which can be met in a hospital, and finally 4) that the treatment be safe for the patients.
International Nuclear Information System (INIS)
Some portion of the radiation dose received by a patient during BNCT consists of primary and secondary gammas. The biological effect of that portion of the dose will depend upon the time history of the delivered dose. The well-known models for relating time-dose effects to clinical experience, are of questionable value in understanding dose effects in the time regime of a few hours, and for doses of less than tolerance. In order to examine the time-dose effect in the regime of interest to BNCT a simple phenomenological model was developed and normalized to the accepted body of clinical experience. The model has been applied to the question of fractionation of BNCT and the results are presented. The model is simply a linear healing model with two time constants. In other words, a first hit of radiation is assumed to wound (or potentiate) a cell. Given time, the cell will fully repair itself. If a second hit occurs before the cell has healed, the cell is killed. Apparently, there are two kinds of healing, one which occurs in 30 to 60 minutes, the other in two to four days. A small fraction of the cells will die on the first hit
Design of Microwave Multibandpass Filters with Quasilumped Resonators
Directory of Open Access Journals (Sweden)
Dejan Miljanović
2015-01-01
Full Text Available Design of RF and microwave filters has always been the challenging engineering field. Modern filter design techniques involve the use of the three-dimensional electromagnetic (3D EM solvers for predicting filter behavior, yielding the most accurate filter characteristics. However, the 3D EM simulations are time consuming. In this paper, we propose electric-circuit models, instead of 3D EM models, suitable for design of RF and microwave filters with quasilumped coupled resonators. Using the diakoptic approach, the 3D filter structure is decomposed into domains that are modeled by electric networks. The coupling between these domains is modeled by capacitors and coupled inductors. Furthermore, we relate the circuit-element values to the physical dimensions of the 3D filter structure. We propose the filter design procedure that is based on the circuit models and fast circuit-level simulations, yielding the element values from which the physical dimensions can be obtained. The obtained dimensions should be slightly refined for achieving the desired filter characteristics. The mathematical problems encountered in the procedure are solved by numerical and symbolic computations. The procedure is exemplified by designing a triple-bandpass filter and validated by measurements on the fabricated filter. The simulation and experimental results are in good agreement.
Frequency weighting filter design for automotive ride comfort evaluation
Du, Feng
2016-04-01
Few study gives guidance to design weighting filters according to the frequency weighting factors, and the additional evaluation method of automotive ride comfort is not made good use of in some countries. Based on the regularities of the weighting factors, a method is proposed and the vertical and horizontal weighting filters are developed. The whole frequency range is divided several times into two parts with respective regularity. For each division, a parallel filter constituted by a low- and a high-pass filter with the same cutoff frequency and the quality factor is utilized to achieve section factors. The cascading of these parallel filters obtains entire factors. These filters own a high order. But, low order filters are preferred in some applications. The bilinear transformation method and the least P-norm optimal infinite impulse response(IIR) filter design method are employed to develop low order filters to approximate the weightings in the standard. In addition, with the window method, the linear phase finite impulse response(FIR) filter is designed to keep the signal from distorting and to obtain the staircase weighting. For the same case, the traditional method produces 0.330 7 m • s-2 weighted root mean square(r.m.s.) acceleration and the filtering method gives 0.311 9 m • s-2 r.m.s. The fourth order filter for approximation of vertical weighting obtains 0.313 9 m • s-2 r.m.s. Crest factors of the acceleration signal weighted by the weighting filter and the fourth order filter are 3.002 7 and 3.011 1, respectively. This paper proposes several methods to design frequency weighting filters for automotive ride comfort evaluation, and these developed weighting filters are effective.
Design and Analysis of Robust Active Damping for LCL Filters using Digital Notch Filters
DEFF Research Database (Denmark)
Yao, Wenli; Yang, Yongheng; Zhang, Xiaobin;
2016-01-01
resonance, where the notch frequency should be aligned exactly to the resonant frequency of the LCL filter. However, parameter variations of the LCL filter as well as the time delay appearing in digital control systems will induce resonance drifting, and thus break this alignment, possibly deteriorating the......Resonant poles of LCL filters may challenge the entire system stability especially in digital-controlled Pulse Width Modulation (PWM) inverters. In order to tackle the resonance issues, many active damping solutions have been reported. For instance, a notch filter can be employed to damp the......-connected PWM inverter verify the effectiveness of the proposed design for robust active damping using digital notch filters....
Design and control of LCL-filter with active damping for Active Power Filter
DEFF Research Database (Denmark)
Zeng, Guohong; Rasmussen, Tonny Wederberg; Ma, L;
2010-01-01
In the application of shunt Active Power Filter (APF) to compensate nonlinear load's harmonic, reactive and negative sequence current, it is more effective to use a LCL-filter than an L-filter as an interface between the Voltage Source Converter (VSC) and grid. In this paper, a designing procedure...... of LCL-filter for APF is introduced, which is aimed for simplified the implementation. To suppress the resonance that may be excited in the system, which brings in stability problems, an active damping control strategy using the current feed-back of the filter capacitor is adopted. By selecting two equal...... or similar inductances, the filter designing become more simple and effective, meanwhile the capacitance requirement is minimized. A pole-zero automatic cancellation phenomenon is discussed in this paper, which can be applied to simplify the current regulator designing. The tuning method is presented, based...
A virtual model of the patient's head for BNCT
International Nuclear Information System (INIS)
The aim of the present work was creating a virtual phantom of a human head for BNCT, as a part of the BNCT programme project. This model is an amplification of the simple model described in earlier publications. It takes into account the major head organs as well as the scalp and skull. The chemical composition of all tissues was modelled according to the recommendations of the ICRP. The organs were parameterized using mathematical formulas based on the human head magnetic resonance images. The model was used for calculating the thermal neutron flux and the injuring (fast neutron, nitrogen and gamma) dose components for the head irradiated using the therapeutic neutron beam, whose parameters were obtained as the result of the modelling of the filter/moderator system for the BNCT therapeutic beam from the MARIA reactor. (authors)
Noniterative Design of 2-Channel FIR Orthogonal Filters
Directory of Open Access Journals (Sweden)
Jiménez M Elena Domínguez
2007-01-01
Full Text Available This paper addresses the problem of obtaining an explicit expression of all real FIR paraunitary filters. In this work, we present a general parameterization of 2-channel FIR orthogonal filters. Unlike other approaches which make use of a lattice structure, we show that our technique designs any orthogonal filter directly, with no need of iteration procedures. Moreover, in order to design an -tap 2-channel paraunitary filterbank, it suffices to choose independent parameters, and introduce them in a simple expression which provides the filter coefficients directly. Some examples illustrate how this new approach can be used for designing filters with certain desired properties. Further conditions can be eventually imposed on the parameters so as to design filters for specific applications.
Asis Mazumder; Pankaj Kumar Roy; Rabindra Nath Barman; Biswajit Mukhopadhay; Mrinmoy Majumder
2008-01-01
The general objective of this study is to estimate the performance of the Horizontal Roughing Filter (HRF) by using Weglin's design criteria based on 1/3–2/3 filter theory. The main objective of the present study is to validate HRF developed in the laboratory with Slow Sand Filter (SSF) as a pretreatment unit with the help of Weglin's design criteria for HRF with respect to raw water condition and neuro-genetic model developed based on the filter dataset. The results achieved from t...
Filter Design With Secrecy Constraints: The MIMO Gaussian Wiretap Channel
Reboredo, Hugo; Xavier, Joao; Rodrigues, Miguel R. D.
2013-08-01
This paper considers the problem of filter design with secrecy constraints, where two legitimate parties (Alice and Bob) communicate in the presence of an eavesdropper (Eve), over a Gaussian multiple-input-multiple-output (MIMO) wiretap channel. This problem involves designing, subject to a power constraint, the transmit and the receive filters which minimize the mean-squared error (MSE) between the legitimate parties whilst assuring that the eavesdropper MSE remains above a certain threshold. We consider a general MIMO Gaussian wiretap scenario, where the legitimate receiver uses a linear Zero-Forcing (ZF) filter and the eavesdropper receiver uses either a ZF or an optimal linear Wiener filter. We provide a characterization of the optimal filter designs by demonstrating the convexity of the optimization problems. We also provide generalizations of the filter designs from the scenario where the channel state is known to all the parties to the scenario where there is uncertainty in the channel state. A set of numerical results illustrates the performance of the novel filter designs, including the robustness to channel modeling errors. In particular, we assess the efficacy of the designs in guaranteeing not only a certain MSE level at the eavesdropper, but also in limiting the error probability at the eavesdropper. We also assess the impact of the filter designs on the achievable secrecy rates. The penalty induced by the fact that the eavesdropper may use the optimal non-linear receive filter rather than the optimal linear one is also explored in the paper.
Review on Desing Beam Shaping Assembly Based on the D-T Reaction for BNCT
International Nuclear Information System (INIS)
Boron Neutron Capture Therapy (BNCT) can be achieved using a compact high energy neutron generator, in which the neutron energy should be in the epithermal range (1 eV < E < 10 keV) with high epithermal flux for treating Glioblastoma Multiforme (GBM). For this purpose, a suitable Beam Shaping Assembly (BSA) of a D-T neutron source is required. A major advantage of a D-T neutron source is the low energy required for the deuteron beam, namely 400 keV. The BSA design consists of a neutron multiplier, a moderator, a reflector, a fast neutron filter, a thermal neutron filter, gamma shielding and a collimator. In this work, the simulation code MCNP-4C is used to simulate the suggested BSA design as given in the literature. Beam parameters obtained by the proposed BSA design for the D-T neutron generator are investigated based on the IAEA recommendation. The results will be presented and discussed, which can provide an appropriate neutron beam for BNCT and suitable for planning in-hospital installations.
Optimal wavelet filter bank design for image fusion
Institute of Scientific and Technical Information of China (English)
Gang Liu; Xueqin Lü; Guohong Huang
2007-01-01
A novel optimization-based method for designing wavelet filter banks in image fusion is proposed. The filter bank design is formulated as a nonlinear optimization problem. The objective function of the optimization problem consists of both the performance metrics of the image fusion, such as the root mean square error (RMSE), and those of individual filters. The optimization problem is solved using simulating annealing.
Development of Graphical User Interface For Microwave Filter Design
Gerard, Djengomemgoto
2016-01-01
This research project aims at developing a low-cost, time-effective and a stand-alone graphical user interface (GUI) that will be used to design microwave filters. Throughout the projects, the main theory behind the technology of microwave filters, their generalized mathematical equations and the analysis of their different circuit topologies have been reviewed. This review helps to extract the necessary information needed for the design of microwave filters. Besides, the guiding principles a...
The Hardware Design of Parameter-Adjustable FIR Filter System
Guosheng Xu
2013-01-01
This design using FPGA parallel architecture, high computing speed and high-speed reliability of USB2.0 interface, designed an FPGA + USB2.0 + computer FIR digital filter system, organically combining the speed of FPGA and flexibility of Computer through USB2.0 bus. The results demonstrated that the coefficients configuring of the system is easy, which can adjust the filter coefficients flexibly according to the actual demand, that it can effectively filter out the noise signals.
Software Would Largely Automate Design of Kalman Filter
Chuang, Jason C. H.; Negast, William J.
2005-01-01
Embedded Navigation Filter Automatic Designer (ENFAD) is a computer program being developed to automate the most difficult tasks in designing embedded software to implement a Kalman filter in a navigation system. The most difficult tasks are selection of error states of the filter and tuning of filter parameters, which are timeconsuming trial-and-error tasks that require expertise and rarely yield optimum results. An optimum selection of error states and filter parameters depends on navigation-sensor and vehicle characteristics, and on filter processing time. ENFAD would include a simulation module that would incorporate all possible error states with respect to a given set of vehicle and sensor characteristics. The first of two iterative optimization loops would vary the selection of error states until the best filter performance was achieved in Monte Carlo simulations. For a fixed selection of error states, the second loop would vary the filter parameter values until an optimal performance value was obtained. Design constraints would be satisfied in the optimization loops. Users would supply vehicle and sensor test data that would be used to refine digital models in ENFAD. Filter processing time and filter accuracy would be computed by ENFAD.
Design of Compact UWB Bandpass Filter with Sharp Rejection Characteristics
Directory of Open Access Journals (Sweden)
Gyuje Sung
2014-07-01
Full Text Available This study presents an Ultra-Wideband (UWB filter with sharp rejection characteristics at the upper Wireless Local Area Network (WLAN band. The filter adopts the modified Composite Right/Left-Handed (CRLH Transmission Lines (TLs, the unit cell of which is theoretically analyzed to derive the design formulas. Subsequently, a UWB bandpass filter is designed using these formulas. The measurement results show that the fabricated UWB bandpass filter has an insertion loss of less than 1.1 dB, bandwidth of 3.1~4.9 GHz and a rejection of more than 50 dB at 5.8 GHz.
An Ant Colony Optimization Algorithm for Microwave Corrugated Filters Design
Mantilla-Gaviria, Ivan A.; Alejandro Díaz-Morcillo; Balbastre-Tejedor, Juan V.
2013-01-01
A practical and useful application of the Ant Colony Optimization (ACO) method for microwave corrugated filter design is shown. The classical, general purpose ACO method is adapted to deal with the microwave filter design problem. The design strategy used in this paper is an iterative procedure based on the use of an optimization method along with an electromagnetic simulator. The designs of high-pass and band-pass microwave rectangular waveguide filters working in the C-band and X-band, res...
Design of Tunable Multiple- Cavity Filter for Optical Fiber Communication
Directory of Open Access Journals (Sweden)
Vahideh Khadem Hosseini Ghasemi
2013-07-01
Full Text Available In this paper a new type of cavity filter is investigated. The device is based on a Fabry–Perot interferometer which employing a cavity and two dielectric Bragg mirrors. The cavity filter uses multi layers of ( and (ZnS to produce a multi -layers ZnS/ cavity filter operating in the center wavelength of 1550 (nm. Zinc sulfide is used in this paper due to its high refractive index, while due to its low refractive index material. The filter is to be coated on Fused Silica having the index of 1.55 and operates at normal incidence. The ZnS/ thin film structure was designed using the Thin Film Design software (TF Calc. The simulation results show that the transmittance of the ZnS/ filter is about 95% for central wavelength of 1550 nm. This filter is essential for monitoring and reconfiguring optical networks.
Design of HTS transmit filter using step impedance resonators
Energy Technology Data Exchange (ETDEWEB)
Sekiya, N., E-mail: nsekiya@yamanashi.ac.j [University of Yamanashi, 4-3-11 Takeda, Kofu 400-8511 (Japan); Nakagawa, Y. [University of Yamanashi, 4-3-11 Takeda, Kofu 400-8511 (Japan); Ohshima, S. [Yamagata University, 4-3-16 Johnan, Yonezawa 992-8510 (Japan)
2010-11-01
We have designed a high-temperature superconducting (HTS) transmit filter with step impedance resonators (SIRs). A transmit filter using half-wavelength straight-line resonators requires substantial spacing between adjacent resonators. This means that the filter needs a large substrate and that the number of poles is limited. Using SIRs overcomes this problem because SIRs are compact and have weak coupling. An electromagnetic simulator based on the moment method was used to design the SIR filter, which has a center frequency of 5 GHz and a bandwidth of 120 MHz. Simulation showed that it is approximately 19% smaller than a conventional half-wavelength straight-line resonator filter. Additionally, the maximum surface current is approximately 17% less than that of the conventional filter.
Robust Two-Dimensional FIR Filter Design for Broadband Beamformers
Nordebo, Sven
1995-01-01
With conventional least squares or Chebyshev approximation methods in the design of a fixed, broadband, delay{and{sum beamformer, the filter weight values may become excessively large. This anomaly is due to large, unspecified regions of the corresponding two{dimensional FIR filter frequency plane. With large filter weight values, the frequency response of the resulting beamformer may be severely degraded due to inaccuracies in sensor positions and/or sensor frequency response. For an adaptiv...
BNCT irradiation facility at the JRR-4
Energy Technology Data Exchange (ETDEWEB)
Torii, Y.; Kishi, T.; Kumada, H.; Yamamoto, K.; Sakurai, F.; Takayanagi, M. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment
2000-10-01
The JRR--4 was modified for fuel enrichment reducing and reactor equipment renewal. And also a medical irradiation facility for the Boron Neutron Capture Therapy (BNCT) was installed at the JRR--4 in that time. The medical irradiation facility has been composed of a heavy water tank, a collimator and an irradiation room. The heavy water tank has four layers of heavy water for spectrum shifter and 75cm-thickness aluminum for the shield of fast neutron. The collimator is for collimating thermal neutron and epithermal neutron using polyethylene with lithium-fluoride and shielding gamma ray by bismuth. The irradiation room has sufficient space at exit side of the beam, to accommodate a large working area for setting the patient. Both of the medical treatment room and the patient-monitoring area were prepared adjacent to the irradiation room. The medical irradiation facility in the JRR-4 is designed to permit selection of neutron energies from thermal neutron to epithermal neutron by changing the thickness of heavy water layers. Therefore it is available to continue the same kind of BNCT with thermal neutron used to perform in the JRR-2, as well as to commence the research and development of BNCT with epithermal neutron, which will make the brain tumor treatment possible at a deep part of brain. The full power operation of the JRR-4 was resumed with LEU fuel in October 1998 and currently performing some experiments to measure the neutron fluxes and physical doses for determinate characterization of the medical irradiation facility. The first medical irradiation for BNCT was carried out on 25th October 1999. The patient was treated by Tsukuba University group using thermal neutron beam included epi-thermal neutrons. (author)
Contourlet Filter Design Based on Chebyshev Best Uniform Approximation
Directory of Open Access Journals (Sweden)
Ming Hou
2010-01-01
Full Text Available The contourlet transform can deal effectively with images which have directional information such as contour and texture. In contrast to wavelets for which there exists many good filters, the contourlet filter design for image processing applications is still an ongoing work. Therefore, this paper presents an approach for designing the contourlet filter based on the Chebyshev best uniform approximation for achieving an efficient image denoising applications using hidden Markov tree models in the contourlet domain. Here, we design both the optimal 9/7 wavelet filter banks with rational coefficients and new pkva 12 filter. In this paper, the Laplacian pyramid followed by the direction filter banks decomposition in the contourlet transform using the two filter banks above and the image denoising applications in the contourlet hidden Markov tree model are implemented, respectively. The experimental results show that the denoising performance of the test image Zelda in terms of peak signal-to-noise ratio is improved by 0.33 dB than using CDF 9/7 filter banks with irrational coefficients on the JPEG2000 standard and standard pkva 12 filter, and visual effects are as good as compared with the research results of Duncan D.-Y. Po and Minh N. Do.
Contourlet Filter Design Based on Chebyshev Best Uniform Approximation
Directory of Open Access Journals (Sweden)
Fang Xiaofeng
2010-01-01
Full Text Available Abstract The contourlet transform can deal effectively with images which have directional information such as contour and texture. In contrast to wavelets for which there exists many good filters, the contourlet filter design for image processing applications is still an ongoing work. Therefore, this paper presents an approach for designing the contourlet filter based on the Chebyshev best uniform approximation for achieving an efficient image denoising applications using hidden Markov tree models in the contourlet domain. Here, we design both the optimal 9/7 wavelet filter banks with rational coefficients and new pkva 12 filter. In this paper, the Laplacian pyramid followed by the direction filter banks decomposition in the contourlet transform using the two filter banks above and the image denoising applications in the contourlet hidden Markov tree model are implemented, respectively. The experimental results show that the denoising performance of the test image Zelda in terms of peak signal-to-noise ratio is improved by 0.33 dB than using CDF 9/7 filter banks with irrational coefficients on the JPEG2000 standard and standard pkva 12 filter, and visual effects are as good as compared with the research results of Duncan D.-Y. Po and Minh N. Do.
Filter-and-Forward Transparent Relay Design for OFDM Systems
Kim, Donggun; Sung, Youngchul
2012-01-01
In this paper, the filter-and-forward (FF) relay design for orthogonal frequency-division multiplexing (OFDM) transmission systems is considered to improve the system performance over simple amplify-and-forward (AF) relaying. Unlike conventional OFDM relays performing OFDM demodulation and remodulating, to reduce processing complexity, the proposed FF relay directly filters the incoming signal with a finite impulse response (FIR) and forwards the filtered signal to the destination. Two design criteria are considered to optimize the relay filter for given source power allocation. One is to minimize the relay transmit power subject to per-subcarrier signal-to-noise ratio (SNR) constraints and the other is to maximize the worst subcarrier channel SNR subject to the total relay transmit power constraint. It is shown that the two problems reduce to semi-definite programming (SDP) problems. Furthermore, the problem of joint source power allocation and relay filter design is considered for the second criterion, and ...
Digital IIR Filter Design using Real Coded Genetic Algorithm
Directory of Open Access Journals (Sweden)
Ranjit Kaur
2013-06-01
Full Text Available The paper develops a technique for the robust and stable design of digital infinite impulse response (IIR filters. As the error surface of IIR filters is generally multi-modal, global optimization techniques are required to design efficient digital IIR filter in order to avoid local minima. In this paper a real-coded genetic algorithm (RCGA with arithmetic-average-bound-blend crossover and wavelet mutation is applied to design the digital IIR filter. A multicriterion optimization is employed as the design criterion to obtain the optimal stable IIR filter that satisfies the different performance requirements like minimizing the Lp-norm approximation error and minimizing the ripple magnitude. The proposed real-coded genetic algorithm is effectively applied to solve the multicriterion, multiparameter optimization problems of low-pass, high-pass, band-pass, and band-stop digital filters design. The computational experiments show that the proposed method is superior or atleast comparable to other algorithms and can be efficiently used for higher order filter design.
Modern analog filter analysis and design a practical approach
Raut, R
2011-01-01
Starting from the fundamentals, the present book describes methods of designing analog electronic filters and illustrates these methods by providing numerical and circuit simulation programs. The subject matters comprise many concepts and techniques that are not available in other text books on the market. To name a few - principle of transposition and its application in directly realizing current mode filters from well known voltage mode filters; an insight into the technological aspect of integrated circuit components used to implement an integrated circuit filter; a careful blending of basi
Rirang Uranium Ore Processing System Design Horizontal Belt Filter
International Nuclear Information System (INIS)
Horizontal belt filter one of the solid-liquid separation process equipment. The design of Horizontal Belt Filter have been conducted for capacity of 250 g/minute. The result obtained was filtering velocity of 0,4 g/cm2 minute. The linear belt speeds 100 cm/minute. The length and width of the belt 125 cm also the filtering cycle of 1,25 minute. The operation of that equipment give result about 77,9 - 79,1% of product cake
Design and Development of Low Pass Filter at 60 GHz
Directory of Open Access Journals (Sweden)
Sanjeev Kumar Shah
2013-07-01
Full Text Available This paper describes the design and development of low pass filter (LPF at 60 GHz. The present design uses stepped impedance method in suspended strip line. The design is modeled and optimized using CST (Computer Simulation Technology microwave studio. The design of a filter types that Tchebysheve 0.1 dB ripple in the passband with the standard bandwidth of 2% and 30 dB attenuation at 94 GHz. The 60 GHz low pass filter exhibits an insertion loss of 1 dB with 3 dB relative bandwidth at a cut-off frequency of 60 GHz and the return loss is better than -18 dB at a cut-off frequency. The designed and fabricated low pass filter shows the good performance for planar integrated millimeter-wave circuits
Chirped-cavity dispersion-compensation filter design
Li, Ya-Ping; Chen, Sheng-Hui; Lee, Cheng-Chung
2006-03-01
A new basic structure of a dispersive-compensation filter, called a chirped-cavity dispersion-compensator (CCDC) filter, was designed to offer the advantages of small ripples in both reflectance and group-delay dispersion (GDD). This filter provides a high dispersion compensation, like the Gires-Tournois interferometer (GTI) filter, and a wide working bandwidth, like the chirped mirror (CM). The structure of the CCDC is a cavity-type Fabry-Perot filter with a spacer layer (2 mH or 2 mL) and a chirped high reflector. The CCDC filter can provide a negative GDD of -50 fs2 over a bandwidth of 56 THz with half the optical thickness of the CM or the GTI.
Accelerator technology and SPECT developments for BNCT
International Nuclear Information System (INIS)
Accelerator-Based BNCT (AB-BNCT) is establishing itself worldwide as the future modality to start the phase of in-hospital facilities. There are projects in Russia, UK, Italy, Japan, Israel, and Argentina to develop AB-BNCT around different types of accelerators. They will be briefly mentioned. In particular, the present status and recent progress of the Argentine project will be presented. The topics will cover: high power ion sources, power and voltage generation systems for a Tandem- Electrostatic Quadrupole (TES Q) accelerator, acceleration tubes, transport of intense beams, beam diagnostics, control systems, high power targets, the 9Be(d,n) reaction as a possible neutron source, Beam Shaping Assemblies (BSA.s), treatment room design, treatment planning assessment of clinical cases, etc. A complete test stand has been built and commissioned for intense proton beam production and characterization. Beams of 10 to 30 m A have been produced and transported during variable periods of operation by means of a pre accelerator and an electrostatic quadrupole doublet to a suppressed Faraday cup. The beam diagnostics has been performed through the observation with digital cameras of induced fluorescence in the residual gas. A 200 kV TES Q accelerator prototype has been constructed and tested and a 600 keV prototype is under construction. Self consistent space charge beam transport simulations have been performed and compared with experimental results. In addition to the traditional 7Li(p,n)7Be reaction, 9Be(d,n)10B using a thin Be target has been thoroughly studied as a candidate for a possible neutron source for deep seated tumors, showing a satisfactory performance. BSA.s and production targets and a treatment room complying with regulations have also been designed. Realistic clinical treatment planning cases for AB-BNCT have been studied showing very good results. Finally we will present advances in the development of a Single Photon Emission Computed Tomography (SPECT
Summary of recent BNCT Polish programme and future plans.
Gryziński, M A; Maciak, M; Wielgosz, M
2015-12-01
In this work we present Polish achievements on the ground of BNCT research. Starting from preliminary built therapeutic stand at MARIA reactor going through designing of unique detectors for in-phantom and in-beam measurements for mixed radiation fields and finally coming to boron carriers synthesizing and examination in cellular and animal models. Now it is planned to restart research on boron compounds in specially designed BIMA line, to set up epithermal neutron irradiation facility for BNCT research and education and to improve recombination detectors for neutron beams characterisation. PMID:26293009
Mechanical design of the TripleWave debris filter
International Nuclear Information System (INIS)
This paper presents the design of the TripleWave debris filter. The function of the debris filter is to reduce the amount of debris that can enter the active fuel region and thereby reduce the risk for damage of the fuel cladding by fretting. The design is aimed at catching long and thin debris as this has proved to constitute the largest fretting risk. The trapping efficiency tests demonstrate that the TripleWave debris filter reduces the risk for harmful debris to enter the fuel assembly significantly compared with the current filter design. Fuel assemblies equipped with the TripleWave filter are thermal hydraulic compatible with assemblies equipped with current filter design even with large amounts of debris trapped in the filter. A full-scale endurance test showed no signs of wear between the components in the lower part of the test assembly. The design is robust and redundant, it is subjected to very small stresses and a very well known and proven material is used and reactor operation without mechanical problems can be expected. (author)
Software Engineering-Based Design for a Bayesian Spam Filter
Directory of Open Access Journals (Sweden)
Mumtaz Mohammed Ali AL-Mukhtar
2010-01-01
Full Text Available The rapid spread and the easy availability of a free e-mail service have made it the medium of choice for the sending of unsolicited advertising and bulk e-mail in general. These messages, known as junk e-mail or spam mail, are an increasing problem to both Internet users and Internet service providers (ISPs. The research resolves one aspect of the spam problem by developing an appropriate filter for the e-mail client. The proposed filter is a combination of three forms of filters: Whitelist, Blacklist, and a Bayesian filter. Whitelist-based filter only accepts e-mails from known addresses. Blacklist filter blocks e-mails from addresses known to send out spam. Bayesian content-based filter makes estimations of spam probability based on the text and filters messages based on a pre-selected threshold.The Bayesian filter is selected to be the main filter. The Bayesian filter is manually trained on a set of gathered e-mails; some of them are spam and the others are legitimate based on the contents of an e-mail. Thereafter the classification phase has been implemented for new entered e-mails. All the required databases are constructed in form of tables stored in the Structured Query Language (SQL server. The filter at the client side can transparently access the database in order to carry on the intended filtering. The proposed system (e-mail client interface and the filters can manage messages written in both Arabic and English languages which is crucial for the users in our region.Software engineering principals are implemented throughout the design process to make the system less vulnerable to faults and easily maintained. The design steps have followed the Waterfall-model using the ASCENT software. A user-friendly interface has been developed to access the features of the spam filter at the client side. Visual Basic version 6 has been used to develop the system. As well, the SQL server has been implemented to build and process the database
Design and Efficient Implementation of Oversampled GDFT Filter Banks for Subband Adaptive Filtering
Weiss, S; Harteneck, M; Stewart, R W
1998-01-01
This paper introduces a polyphase implementation and design of an oversampled K-channel generalized DFT (GDFT) filter bank, which can be employed for subband adaptive filtering, and therefore is required to have a low aliasing level in the subband signals. A polyphase structure is derived which can be factorized into a real valued polyphase network and a GDFT modulation. For the latter, an FFT realization may be used, yielding a highly efficient polyphase implementation for arbitrary integer ...
An in-phantom comparison of neutron fields for BNCT
International Nuclear Information System (INIS)
Previously, the authors have developed the in-phantom neutron field assessment parameters T and D (Tumor) for the evaluation of epithermal neutron fields for use in BNCT. These parameters are based on an energy-spectrum-dependent neutron normal-tissue RBE and the treatment planning methodology of Gahbauer and his co-workers, which includes the effects of dose fractionation. In this paper, these neutron field assessment parameters were applied to The Ohio State University (OSU) design of an Accelerator Based Neutron Source (ABNS) (hereafter called the OSU-ABNS) and the Brookhaven Medical Research Reactor (BMRR) epithermal neutron beam (hereafter called the BMRR-ENB), in order to judge the suitability of the OSU-ABNS for BNCT. The BMRR-ENB was chosen as the basis for comparison because it is presently being used in human clinical trials of BNCT and because it is the standard to which other neutron beams are most often compared
INEEL BNCT Research Program Annual Report, CY-2000
Energy Technology Data Exchange (ETDEWEB)
Venhuizen, James Robert
2001-03-01
This report is a summary of the activities conducted in conjunction with the Idaho National Engineering and Environmental Laboratory (INEEL) Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 2000. Applications of supportive research and development, as well as technology deployment in the fields of chemistry, radiation physics and dosimetry, neutron source design and demonstration, and support the Department of Energy’s (DOE) National BNCT Program goals are the goals of this Program. Contributions from the individual contributors about their projects are included, specifically described are the following, chemistry: analysis of biological samples and an infrared blood-boron analyzer, and physics: progress in the patient treatment planning software, measurement of neutron spectra for the Argentina RA-6 reactor, and recalculation of the Finnish research reactor FiR 1 neutron spectra, BNCT accelerator technology, and modification to the research reactor at Washington State University for an epithermal-neutron beam.
A comparison of methods for DPLL loop filter design
Aguirre, S.; Hurd, W. J.; Kumar, R.; Statman, J.
1986-01-01
Four design methodologies for loop filters for a class of digital phase-locked loops (DPLLs) are presented. The first design maps an optimum analog filter into the digital domain; the second approach designs a filter that minimizes in discrete time weighted combination of the variance of the phase error due to noise and the sum square of the deterministic phase error component; the third method uses Kalman filter estimation theory to design a filter composed of a least squares fading memory estimator and a predictor. The last design relies on classical theory, including rules for the design of compensators. Linear analysis is used throughout the article to compare different designs, and includes stability, steady state performance and transient behavior of the loops. Design methodology is not critical when the loop update rate can be made high relative to loop bandwidth, as the performance approaches that of continuous time. For low update rates, however, the miminization method is significantly superior to the other methods.
Quality assurance of BNCT dosimetry
International Nuclear Information System (INIS)
The Phase I clinical trials for boron neutron capture therapy (BNCT) started in May 1999 in Otaniemi, Espoo. For BNCT no uniform international guidance for the quality assurance of dosimetry exists, so far. Because of the complex dose distribution with several different dose components, the international recommendations on conventional radiotherapy dosimetry are not applicable in every part. Therefore, special guidance specifically for BNCT is needed. To obtain such guidelines a European collaboration project has been defined. The aim of the project is a generally accepted Code of Practice for use by all European BNCT centres. This code will introduce the traceability of the dosimetric methods to the international measurement system. It will also ensure the comparability of the results in various BNCT beams and form the basis for the comparison of the treatment results with the conventional radiotherapy or other treatment modalities. The quality assurance of the dosimetry in BNCT in Finland covers each step of the BNCT treatment, which include dose planning imaging, dose planning, boron infusion, boron kinetics, patient positioning, monitoring of the treatment beam, characterising the radiation spectrum, calibration of the beam model and the dosimetric measurements both in patients (in viva measurements) and in various phantoms. The dose planning images are obtained using a MR scanner with MRI sensitive markers and the dose distribution is computed with a dose planning software BNCTRtpe. The program and the treatment beam (DORT) model used have been verified with measurements and validated with MCNP calculations in phantom. Dosimetric intercomparison has been done with the Brookhaven BNCT beam (BMRR). Before every patient irradiation the relationship between the beam monitor pulse rate and neutron fluence rate in the beam is checked by activation measurements. Kinetic models used to estimate the time-behavior of the blood boron concentration have been verified
A Transmission-Filter Coronagraph: Design and Test
Ren, Deqing; Zhu, Yongtian
2015-01-01
We propose a transmission-filter coronagraph for direct imaging of Jupiter-like exoplanets with ground-based telescopes. The coronagraph is based on a transmission filter that consists of finite number of transmission steps. A discrete optimization algorithm is proposed for the design of the transmission filter that is optimized for ground-based telescopes with central obstructions and spider structures.We discussed the algorithm that is applied for our coronagraph design. To demonstrate the performance of the coronagraph, a filter was manufactured and laboratory tests were conducted. The test results show that the coronagraph can achieve a high contrast of 10 to -6.5 at an inner working angle of 5{\\lambda}/D, which indicates that our coronagraph can be immediately used for the direct imaging of Jupiter-like exoplanets with ground-based telescopes.
Design and Analysis of Parallel-Coupled Line Bandpass Filter
Talib Mahmood Ali
2013-01-01
A compact microwave parallel coupled line resonator seventh order bandpass filter (BPF) is presented in this paper, consist a 8-parallel coupled line pairs designed for a maximally flat response or Butterworth response at a center frequency of 2.44175 GHz and with a fractional bandwidth, Δ= 0.035. The filter was implemented in a microstrip platform with a permittivity of the substrate Er=4.4 and a substrate height h=1.5mm. The physical parameters of the parallel coupled line filter sections w...
Broadband notch filter design for millimeter-wave plasma diagnostics
DEFF Research Database (Denmark)
Furtula, Vedran; Michelsen, Poul; Leipold, Frank;
2010-01-01
Notch filters are integrated in plasma diagnostic systems to protect millimeter-wave receivers from intensive stray radiation. Here we present a design of a notch filter with a center frequency of 140 GHz, a rejection bandwidth of ∼ 900 MHz, and a typical insertion loss below 2 dB in the passband...... in the cylindrical cavities is the fundamental TE11. The performance of the constructed filter is measured using a vector network analyzer monitoring a total bandwidth of 30 GHz. We compare the measurements with numerical simulations. © 2010 EURATOM...
An Ant Colony Optimization Algorithm for Microwave Corrugated Filters Design
Directory of Open Access Journals (Sweden)
Ivan A. Mantilla-Gaviria
2013-01-01
Full Text Available A practical and useful application of the Ant Colony Optimization (ACO method for microwave corrugated filter design is shown. The classical, general purpose ACO method is adapted to deal with the microwave filter design problem. The design strategy used in this paper is an iterative procedure based on the use of an optimization method along with an electromagnetic simulator. The designs of high-pass and band-pass microwave rectangular waveguide filters working in the C-band and X-band, respectively, for communication applications, are shown. The average convergence performance of the ACO method is characterized by means of Monte Carlo simulations and compared with that obtained with the well-known Genetic Algorithm (GA. The overall performance, for the simulations presented herein, of the ACO is found to be better than that of the GA.
Energy Technology Data Exchange (ETDEWEB)
Mandal, Subhra [Department of Tumor Immunology, Radboud University Nijmegen Medical Centre (Netherlands); Bakeine, Gerald J., E-mail: Jamesbakeine1@yahoo.com [Department of Internal Medicine and Therapeutics-Section of Clinical Toxicology, University of Pavia, Piazza Botta 10, 27100 Pavia (Italy); Krol, Silke [Institute of Neurology, Fondazione IRCCS Carlo Besta, Milan (Italy); Ferrari, Cinzia; Clerici, Anna M.; Zonta, Cecilia; Cansolino, Laura [Department of Surgery, Laboratory of Experimental Surgery, University of Pavia (Italy); Ballarini, Francesca [Department of Nuclear and Theoretical Physics, University of Pavia (Italy); Bortolussi, Silva [Department of Nuclear and Theoretical Physics, University of Pavia (Italy)] [National Institute of Nuclear Physics (INFN), Section of Pavia (Italy); Stella, Subrina; Protti, Nicoletta [Department of Nuclear and Theoretical Physics, University of Pavia (Italy); Bruschi, Piero [National Institute of Nuclear Physics (INFN), Section of Pavia (Italy); Altieri, Saverio [Department of Nuclear and Theoretical Physics, University of Pavia (Italy)] [National Institute of Nuclear Physics (INFN), Section of Pavia (Italy)
2011-12-15
The aim of this study is to optimize targeted boron delivery to cancer cells and its tracking down to the cellular level. To this end, we describe the design and synthesis of novel nanovectors that double as targeted boron delivery agents and fluorescent imaging probes. Gold nanoparticles were coated with multilayers of polyelectrolytes functionalized with the fluorescent dye (FITC), boronophenylalanine and folic acid. In vitro confocal fluorescence microscopy demonstrated significant uptake of the nanoparticles in cancer cells that are known to overexpress folate receptors. - Highlights: Black-Right-Pointing-Pointer Synthesis of multi-labeled gold nanoparticles for selective boron delivery to tumor cells. Black-Right-Pointing-Pointer Tumor selectivity is achieved through folic acid receptor targeting. Black-Right-Pointing-Pointer Optical fluorescent microscopy allows tracking of cellular uptake of the gold nanoparticle. Black-Right-Pointing-Pointer In vitro tests demonstrate selective nanoparticle up in folate receptor positive tumor cells.
International Nuclear Information System (INIS)
The aim of this study is to optimize targeted boron delivery to cancer cells and its tracking down to the cellular level. To this end, we describe the design and synthesis of novel nanovectors that double as targeted boron delivery agents and fluorescent imaging probes. Gold nanoparticles were coated with multilayers of polyelectrolytes functionalized with the fluorescent dye (FITC), boronophenylalanine and folic acid. In vitro confocal fluorescence microscopy demonstrated significant uptake of the nanoparticles in cancer cells that are known to overexpress folate receptors. - Highlights: ►Synthesis of multi-labeled gold nanoparticles for selective boron delivery to tumor cells. ► Tumor selectivity is achieved through folic acid receptor targeting. ► Optical fluorescent microscopy allows tracking of cellular uptake of the gold nanoparticle. ► In vitro tests demonstrate selective nanoparticle up in folate receptor positive tumor cells.
Novel design method for generalized lattice filters
Agger, Søren; Povlsen, Jørn Hedegaard; Leick, Lasse; Zauner, Dan Anker
2003-01-01
A new design method for wide-band gain equalizers using cascaded MZI's is proposed. The method achieves a given accuracy with fewer stages than previously described methods. Furthermore, the method is capable of minimizing PDL.
Novel design method for generalized lattice filters
DEFF Research Database (Denmark)
Agger, Søren; Povlsen, Jørn Hedegaard; Leick, Lasse; Zauner, Dan Anker
A new design method for wide-band gain equalizers using cascaded MZI's is proposed. The method achieves a given accuracy with fewer stages than previously described methods. Furthermore, the method is capable of minimizing PDL.......A new design method for wide-band gain equalizers using cascaded MZI's is proposed. The method achieves a given accuracy with fewer stages than previously described methods. Furthermore, the method is capable of minimizing PDL....
International Nuclear Information System (INIS)
A dog was diagnosed with osteosarcoma (8x6x5cm) in the right wing of ilium by radiography, radionuclide scintigraphy and histological study of biopsy material. The treatment plan was as follows: γ-therapy in combination with chemotherapy; prevention of hematogenous pulmonary metastases by the transfusion of 130 ml of allogenic marrow from a healthy donor; administration of 11.4g 10B-boronphenylalanine into the right iliac artery; resection of the right iliac wing with the osteosarcoma lesion; neutron irradiation (MEPhI Reactor) of the bone fragment (dose on healthy osteocytes - 15±4 Gy (W), on tumor - 50±9 Gy (W); reimplantation and fixation of the fragment; three courses of adjuvant chemotherapy. The doses were determined in full-scale calculations of the reactor radiation fields with a model of the bone under the code RADUGA. The 10B concentration (μg/g) in the bone was: normal tissue - 9±3, tumor - 28±5. In 24 hours post operation the dog was able to walk using the treated limb, and 6 months later it moved freely. The patient has been under observation for 30 months. The results of the research demonstrate complete cure. The use of similar treatment plans improves the therapeutic efficiency of BNCT. (author)
FULL SCALE REGENERABLE HEPA FILTER DESIGN USING SINTERED METAL FILTER ELEMENTS
International Nuclear Information System (INIS)
A Department of Energy funded contract involved the development of porous metal as a HEPA filter, and the subsequent design of a full-scale regenerable HEPA filtration system (RHFS). This RHFS could replace the glass fiber HEPA filters currently being used on the high level waste (HLW) tank ventilation system with a system that would be moisture tolerant, durable, and cleanable in place. The origins of the contract are a 1996 investigation at the Savannah River Technology Center (SRTC) regarding the use of porous metal as a HEPA filter material. This contract was divided into Phases I, IIA and IIB. Phase I of the contract evaluated simple filter cylinders in a simulated High Level Waste (HLW) environment and the ability to clean and regenerate the filter media after fouling. Upon the successful completion of Phase I, Phase IIA was conducted, which included lab scale prototype testing and design of a full-scale system. The work completed under Phase IIA included development of a full-scale system design, development of a filter media meeting the HEPA filtration efficiency that would also be regenerable using prescribed cleaning procedures, and the testing of a single element system prototype at Savannah River. All contract objectives were met. The filter media selected was a nickel material already under development at Mott, which met the HEPA filtration efficiency standard. The Mott nickel media met and exceeded the HEPA requirement, providing 99.99% removal against a requirement of 99.97%. Double open-ended elements of this media were provided to the Savannah River Test Center for HLW simulation testing in the single element prototype filter. These elements performed well and further demonstrated the practicality of a metallic media regenerable HEPA filter system. An evaluation of the manufacturing method on many elements demonstrated the reproducibility to meet the HEPA filtration requirement. The full-scale design of the Mott RHFS incorporated several important
FULL SCALE REGENERABLE HEPA FILTER DESIGN USING SINTERED METAL FILTER ELEMENTS
Energy Technology Data Exchange (ETDEWEB)
Gil Ramos; Kenneth Rubow; Ronald Sekellick
2002-11-27
A Department of Energy funded contract involved the development of porous metal as a HEPA filter, and the subsequent design of a full-scale regenerable HEPA filtration system (RHFS). This RHFS could replace the glass fiber HEPA filters currently being used on the high level waste (HLW) tank ventilation system with a system that would be moisture tolerant, durable, and cleanable in place. The origins of the contract are a 1996 investigation at the Savannah River Technology Center (SRTC) regarding the use of porous metal as a HEPA filter material. This contract was divided into Phases I, IIA and IIB. Phase I of the contract evaluated simple filter cylinders in a simulated High Level Waste (HLW) environment and the ability to clean and regenerate the filter media after fouling. Upon the successful completion of Phase I, Phase IIA was conducted, which included lab scale prototype testing and design of a full-scale system. The work completed under Phase IIA included development of a full-scale system design, development of a filter media meeting the HEPA filtration efficiency that would also be regenerable using prescribed cleaning procedures, and the testing of a single element system prototype at Savannah River. All contract objectives were met. The filter media selected was a nickel material already under development at Mott, which met the HEPA filtration efficiency standard. The Mott nickel media met and exceeded the HEPA requirement, providing 99.99% removal against a requirement of 99.97%. Double open-ended elements of this media were provided to the Savannah River Test Center for HLW simulation testing in the single element prototype filter. These elements performed well and further demonstrated the practicality of a metallic media regenerable HEPA filter system. An evaluation of the manufacturing method on many elements demonstrated the reproducibility to meet the HEPA filtration requirement. The full-scale design of the Mott RHFS incorporated several important
International Nuclear Information System (INIS)
Our research group at the Radiation Pathology Division of the Department of Radiobiology (National Atomic Energy Commission) has previously demonstrated the therapeutic efficacy of different BNCT protocols to treat oral cancer in an experimental hamster cheek pouch model. In particular, to perform studies in this experimental model at the thermal facility constructed at RA-3, we designed and constructed a shielding device for thermal neutrons, to be able to expose the cheek pouch while minimizing the dose to the rest of the body. This device allowed for the irradiation of one animal at a time. Given the usage rate of the device, the aim of the present study was to design and construct an optimized version of the existing shielding device that would allow for the simultaneous irradiation of 2 animals at the thermal facility of RA-3. Taking into account the characteristics of the neutron source and preliminary biological assays, we designed the shielding device for the body of the animal, i.e. a rectangular shaped box with double acrylic walls. The space between the walls contains a continuous filling of 6Li2CO3 (95% enriched in 6Li), approximately 6 mm thick. Two small windows interrupt the shield at one end of the box through which the right pouch of each hamster is everted out onto an external acrylic shelf for exposure to the neutron flux. The characterization of the shielding device showed that the neutron flux was equivalent at both irradiation positions confirming that we were able to design and construct a new shielding device that allows for the irradiation of 2 animals at the same time at the thermal facility of RA-3. This new version of the shielding device will reduce the number of interventions of the reactor operators, reducing occupational exposure to radiation and will make the procedure more efficient for researchers. In addition, we addressed the generation of tritium as a product of the capture reaction in lithium. It was considered as a potential
Principles and Design Rationale of Composition Filters
Bergmans, Lodewijk; Aksit, Mehmet; Filman, Robert E.; Elrad, Tzilla; Clarke, Siobhán; Akşit, Mehmet
2004-01-01
A wide range of aspect-oriented programming languages has appeared in the past years [7]. Current research on future generation AOP languages is addressing issues like flexibility, expressive power and safety. We think that it is important to understand the motivations and design decisions of the fi
Design and control of hybrid active power filters
Lam, Chi-Seng
2014-01-01
Design and Control of Hybrid Active Power Filters presents an overview of the current quality problems and their compensators. To get a balance between the system cost and performance, hybrid active power filters (HAPFs) are valuable. The book presents the coverage of resonance phenomena prevention capability, filtering performance and system robustness analysis of HAPF; nonlinear inverter current slope characteristics and their linear operation region requirement analysis of the hysteresis PWM for the HAPF; minimum inverter capacity design procedure of HAPF, adaptive dc-link voltage controller for the HAPF and the real design example of a 220V 10kVA HAPF, in which the system performance analysis method, minimum dc voltage deduction concept and adaptive dc voltage idea can be further extended into the other active compensators, such as APF, static synchronous compensator STATCOM, etc. This book will benefit researchers, graduate students, and electrical power engineers in the field of power-quality compensati...
Ken Smigielski; Farhang Akbar-Khanzadeh
2009-01-01
An air filter is a significant element of any mechanical ventilation system. However, the importance and performance evaluation of air filters have not been well publicized and related scientific reports are scarce. In this study, a transportable, off-line, air filter-testing unit (the Unit) was designed and utilized to simulate the filter housing of a mechanical ventilation system. The Unit was designed, assembled, and operated in a laboratory. To demonstrate the applications of the Unit, a ...
UWB microstrip filter design using a time-domain technique
Tekin, İbrahim; TEKIN Ibrahim
2005-01-01
A time-domain technique is proposed for ultra-wideband (UWB) microstrip-filter design. The design technique uses the reflection coefficient (S11) specified in the frequency domain. When the frequency response of the UWB filter is given, the response will be approximated by a series of UWB pulses in the time domain. The UWB pulses are Gaussian pulses of the same bandwidth with different time delays. The method tries to duplicate the reflection scenario in the time domain for very narrow Gaussi...
NEW DESIGN OF ROBUST OPTIMAL ARBITRARY TIME-DELAY FILTER
Institute of Scientific and Technical Information of China (English)
WANG Xiaojun; SHAO Huihe
2007-01-01
Zero placement method in the frequency domain is utilized to design robust multi-hump EI optimal arbitrary time-delay filter (OATF) by placing two or more filter zeros near the system poles. A total insensitive OATF can be also achieved if the problem of insensitivity to damping errors is considered. This design strategy is easier to derive and implement. Applications in the anti-swing control of overhead cranes verify the fine performance of this strategy. A better suppression of the load vibrations is obtained using the proposed new OATF, which is more robust to the variation of the cable length.
Designing Asynchronous Circuits for Low Power: An IFIR Filter
DEFF Research Database (Denmark)
Nielsen, Lars Skovby; Sparsø, Jens
1999-01-01
This paper addresses the design of asynchronous circuits for low power through an example: a filter bank for a digital hearing aid. The asynchronous design re-implements an existing synchronous circuit which is used in a commercial product. For comparison, both designs have been fabricated in the...... by numerically small samples). Apart from the improved RAM design, these measures are only viable in an asynchronous design. The principles and techniques explained in this paper are of a general nature, and they apply to the design of asynchronous low-power digital signal-processing circuits in a...
Directory of Open Access Journals (Sweden)
Shailendra Singh Ojha
2013-04-01
Full Text Available The purpose of this paper is to design a microstrip patch antenna with low pass filter for efficient rectenna design this structure having the property of rejecting higher harmonics than 2GHz. As the design frequency is 2GHz.in first step we design a patch antenna in second step we design patch antenna with low pass filter and combine these two. The IE3D software is used for the simulation of this structure.
Shailendra Singh Ojha; P. K. Singhal; Anshul agarawal; Akhilesh Gupta
2013-01-01
The purpose of this paper is to design a microstrip patch antenna with low pass filter for efficient rectenna design this structure having the property of rejecting higher harmonics than 2GHz. As the design frequency is 2GHz.in first step we design a patch antenna in second step we design patch antenna with low pass filter and combine these two. The IE3D software is used for the simulation of this structure.
Design of Microstrip UWB bandpass Filter using Multiple Mode Resonator
Directory of Open Access Journals (Sweden)
Vinay Kumar Sharma
2014-10-01
Full Text Available In this letter, we present a design of microstrip ultrawideband (UWB bandpass filter (BPF for the use in UWB wireless communication application set by Federal Communications Commission (FCC. The UWB filter is realized with a Basic MMR (Multiple Mode Resonators structure feed by interdigital coupled lines for achieving higher degree of coupling. The structure is optimized for high selectivity, inband and stopband performance. Finally for fabrication of this structure Rogers RT5880 substrate of thickness 0.4mm with Dielectric constant 2.2 is used. The electromagnetic simulation software, Computer Simulation Technology Microwave Studio (CST MWS is used for the simulation and analysis of the designed structure. The comparison between simulated and fabricated measured result shows good agreement. The insertion loss of proposed filter is greater then 0.2 dB at 6.8 GHz and very flat over whole pass band also returns loss is less then -12db.
Design of Low Pass Digital FIR Filter Using Cuckoo Search Algorithm
Taranjit Singh; Harvinder Singh Josan
2014-01-01
This paper presents a novel approach of designing linear phase FIR low pass filter using cuckoo Search Algorithm (CSA). FIR filter design is a multi-modal optimization problem. The conventional optimization techniques are not efficient for digital filter design. An iterative method is introduced to find the best solution of FIR filter design problem.Flat passband and high stopband attenuation are the major characteristics required in FIR filter design. To achieve these charact...
Design and Analysis of Parallel-Coupled Line Bandpass Filter
Directory of Open Access Journals (Sweden)
Talib Mahmood Ali
2013-09-01
Full Text Available A compact microwave parallel coupled line resonator seventh order bandpass filter (BPF is presented in this paper, consist a 8-parallel coupled line pairs designed for a maximally flat response or Butterworth response at a center frequency of 2.44175 GHz and with a fractional bandwidth, Δ= 0.035. The filter was implemented in a microstrip platform with a permittivity of the substrate Er=4.4 and a substrate height h=1.5mm. The physical parameters of the parallel coupled line filter sections were optimized using the Microwave Office software to provide the closest values of the bandpass filter prototype values and electrical lengths for a given set of filter specifications. The simulation of direct calculation, show the attenuation S11 response was observed at 2.44175 GHz with a value of -25 dB and the corresponding Insertion Loss S21 is - 1.8dB while the optimized design S11 response at the centre frequency with a value of -113 dB and the corresponding Insertion Loss S21 is -2.2dB.
Gravitation search algorithm: Application to the optimal IIR filter design
Directory of Open Access Journals (Sweden)
Suman Kumar Saha
2014-01-01
Full Text Available This paper presents a global heuristic search optimization technique known as Gravitation Search Algorithm (GSA for the design of 8th order Infinite Impulse Response (IIR, low pass (LP, high pass (HP, band pass (BP and band stop (BS filters considering various non-linear characteristics of the filter design problems. This paper also adopts a novel fitness function in order to improve the stop band attenuation to a great extent. In GSA, law of gravity and mass interactions among different particles are adopted for handling the non-linear IIR filter design optimization problem. In this optimization technique, searcher agents are the collection of masses and interactions among them are governed by the Newtonian gravity and the laws of motion. The performances of the GSA based IIR filter designs have proven to be superior as compared to those obtained by real coded genetic algorithm (RGA and standard Particle Swarm Optimization (PSO. Extensive simulation results affirm that the proposed approach using GSA outperforms over its counterparts not only in terms of quality output, i.e., sharpness at cut-off, smaller pass band ripple, higher stop band attenuation, but also the fastest convergence speed with assured stability.
105 GHz Notch Filter Design for Collective Thomson Scattering
DEFF Research Database (Denmark)
Furtula, Vedran; Michelsen, Poul; Leipold, Frank; Johansen, T.; Korsholm, Søren Bang; Meo, Fernando; Moseev, Dmitry; Nielsen, Stefan Kragh; Salewski, Mirko; Stejner Pedersen, Morten
2011-01-01
A millimeter-wave notch filter with 105-GHz center frequency, >20-GHz passband coverage, and 1-GHz rejection bandwidth has been constructed. The design is based on a fundamental rectangular waveguide with cylindrical cavities coupled by narrow iris gaps, i.e., small elongated holes of negligible...
Design and analysis of electromagnetic interference filters and shields
McDowell, Andrew Joel
Electromagnetic interference (EMI) is a problem of rising prevalence as electronic devices become increasingly ubiquitous. EMI filters are low pass filters intended to prevent the conducted electric currents and radiated electromagnetic fields of a device from interfering with the proper operation of other devices. Shielding is a method, often complementary to filtering, that typically involves enclosing a device in a conducting box in order to prevent radiated EMI. This dissertation includes three chapters related to the use of filtering and shielding for preventing electromagnetic interference. The first chapter deals with improving the high frequency EMI filtering performance of surface mount capacitors on printed circuit boards (PCBs). At high frequencies, the impedance of a capacitor is dominated by a parasitic inductance, thus leading to poor high frequency filtering performance. Other researchers have introduced the concept of parasitic inductance cancellation and have applied this concept to improving the filtering performance of volumetrically large capacitors at frequencies up to 100 MHz. The work in this chapter applies the concept of parasitic inductance cancellation to much smaller surface mount capacitors at frequencies up to several gigahertz. The second chapter introduces a much more compact design for applying parasitic inductance cancellation to surface mount capacitors that uses inductive coupling between via pairs as well as coplanar traces. This new design is suited for PCBs having three or more layers including solid ground and/or power plane(s). This design is demonstrated to be considerably more effective in filtering high frequency noise due to crosstalk than a comparable conventional shunt capacitor filter configuration. Finally, chapter 3 presents a detailed analysis of the methods that are used to decompose the measure of plane wave shielding effectiveness into measures of absorption and reflection. Textbooks on electromagnetic
Sagar R. Patil; Prof. Sachin V. Lomte
2015-01-01
In automobile vehicles mostly plastic molded panel filters used for the purpose of engine air filtration. Fibrous structured cellulose media were being used with different permeability’s according to requirement of rated air flow rate required for the engine. To optimize the filter pleat design of automotive panel air filter, it is important to study correlation of pressure drop, dust holding capacity & efficiency. The main role of a filter is to provide least pressure drop with h...
Three different criteria for the design of two-dimensional zero phase FIR digital filters
DEFF Research Database (Denmark)
Gislason, E.; Johansen, M.; Conradsen, Knut;
1993-01-01
An error criterion for the design of FIR filters is proposed. Filters with relatively many free filter coefficients are designed using the Chebyshev, the weighted-least-squares (WLS), and a new partitioned minimax error criterion, and the performance of the filters is compared. A general and fast...... technique for the WLS design is also presented.>...
An Applied Method for Designing Maximally Decimating Non-uniform Filter Banks
Institute of Scientific and Technical Information of China (English)
无
2003-01-01
Assembling individual line phase filters to form a multi-channel filter bank allows the synthesis filter to be similar to corresponding analysis filters, and the design calculation can be simple. The appropriate relations between synthesis filters and analysis filters eliminate most aliasing resulting from decimation in non-uniform maximally decimating filter banks, and LS algorithm and Remez algorithm are used to optimize the composite character. This design method can achieve approximate Perfect-Reconstruction. An example is given in which the general parameter filters with approximate line phase are used as units of a filter bank.
Some Aspects on Filter Design for Target Tracking
Bertil Ekstrand
2012-01-01
Tracking filter design is discussed. It is argued that the basis of the present stochastic paradigm is questionable. White process noise is not adequate as a model for target manoeuvring, stochastic least-square optimality is not relevant or required in practice, the fact that requirements are necessary for design is ignored, and root mean square (RMS) errors are insufficient as performance measure. It is argued that there is no process noise and that the covariance of the assumed process noi...
Design Optimization of Diesel Particulate Filter Using CFD
Mr. Y. Rajasekhar Reddy; Mr. K. Srinivasa Chalapathi
2015-01-01
The diesel particulate filter (DPF) is a device designed to remove diesel particulate matter or soot from the exhaust gas of a diesel engine. A series of tests have been performed on a downscaled DPF prototype. This prototype had high filtration efficiency. Then the next step is to study the soot and ash handling capacity of DPF system and perform tests on a full-scale prototype. In order to move forward to the next step the functionality of the filter should be investigated. More...
Analysis and Design of Offset QPSK Using Redundant Filter Banks
International Nuclear Information System (INIS)
This paper considers the analysis and design of OQPSK digital modulation. We first establish the discrete time formulation, which allows us to find the equivalent redundant filter banks. It is well known that redundant filter banks are related with redundant transformation of the Frame theory. According to the Frame theory, the redundant transformations and corresponding representations are not unique. In this way, we show that the solution to the pulse shaping problem is not unique. Then we use this property to minimize the effect of the channel noise in the reconstructed symbol stream. We evaluate the performance of the digital communication using numerical examples.
Providing Eligibility Criteria On Turbocharger Filter Silencer Design Processes
Directory of Open Access Journals (Sweden)
Adem GÜLERYÜZ
2013-06-01
Full Text Available Supply of ventilation air to either the engine room or diesel engine directly affects engine performances. Main criteria is supply of air volume and pressure into the cylinder. When Air starts to come until the cylinders, there many points which behave as restrictions. These are ventilation grills. ventilation fans, ventilation casings, misteliminators, manual or pneumatically adjusted fan dampers, number of bending of ventilation casing, cleanness of casings, air flow speed, air filters, turbocharger filter and silencers, engine’s scavenge air cooler restrictions. Here, we focused on optimum required air need through turbocharger for local diesel engine. While researching actual need, new turbocharger filter were designed and manufactured for engine manufacturer.
Directory of Open Access Journals (Sweden)
Ken Smigielski
2009-04-01
Full Text Available An air filter is a significant element of any mechanical ventilation system. However, the importance and performance evaluation of air filters have not been well publicized and related scientific reports are scarce. In this study, a transportable, off-line, air filter-testing unit (the Unit was designed and utilized to simulate the filter housing of a mechanical ventilation system. The Unit was designed, assembled, and operated in a laboratory. To demonstrate the applications of the Unit, a series of air filter handling and installation scenarios was performed to determine the characteristic curve and capture efficiencies of a selected set of HEPA filters. The research project produced a transportable, closed system air filter testing unit. The Unit incorporated a fan, a damper to adjust air flowrate, a filter-housing (consisting of a mixing chamber, a filter-frame, and a pressure-gauge, and ducting with ports to introduce challenge particles and monitor them after filtration. By using the Unit, the detrimental effects of damaged filter-media, damaged filter-gasket, and improper installation of air filters on their capture efficiencies were clearly demonstrated. An air filter testing unit, similar to the Unit presented here, can readily be designed, fabricated, and assembled to simulate the filter-housing of mechanical ventilation systems. The assembled unit can be used (1 to determine capture efficiency of air filters and their characteristic curve, (2 to demonstrate the negative effects of improper handling and installation of air filters, and (3 as an effective investigative and educational tool.
Energy Technology Data Exchange (ETDEWEB)
Choi, Hee Dong; Kim, Chang Shuk; Byun, Soo Hyun; Lee, Jae Yun; Sun, Gwang Min; Kim, Suk Kwon [Seoul National University, (Korea)
2000-04-01
I. Objectives and Necessity of the Project. Development of a boron concentration analysis system used for BNCT. Development of test techniques for BNCT facility. II. Contents and Scopes of the Project. (1) Design of a boron concentration analysis system at HANARO. (2) Component machining and instruments purchase, performance test. (3) Calculation and measurement of diffracted polychromatic beam quality. (4) Test procedures for boron concentration analysis system and BNCT facility. III. Result of the Project (1) Diffracted neutron beam quality for boron concentration analysis. (neutron flux: 1.2 * 10{sup 8} n/cm{sup 2}s, Cd-ratio : 1,600) (2) Components and instruments of the boron concentration analysis system. (3) Diffracted neutron spectrum and flux. (4) Test procedures for boron concentration analysis system and BNCT facility. 69 refs., 44 figs., 14 tabs. (Author)
Ridge filter design for a particle therapy line
Kim, Chang Hyeuk; Han, Garam; Lee, Hwa-Ryun; Kim, Hyunyong; Jang, Hong Suk; Kim, Jeong Hwan; Park, Dong Wook; Jang, Sea Duk; Hwang, Won Taek; Kim, Geun-Beom; Yang, Tae-Keun
2014-05-01
The beam irradiation system for particle therapy can use a passive or an active beam irradiation method. In the case of an active beam irradiation, using a ridge filter would be appropriate to generate a spread-out Bragg peak (SOBP) through a large scanning area. For this study, a ridge filter was designed as an energy modulation device for a prototype active scanning system at MC-50 in Korea Institute of Radiological And Medical Science (KIRAMS). The ridge filter was designed to create a 10 mm of SOBP for a 45-MeV proton beam. To reduce the distal penumbra and the initial dose, [DM] determined the weighting factor for Bragg Peak by applying an in-house iteration code and the Minuit Fit package of Root. A single ridge bar shape and its corresponding thickness were obtained through 21 weighting factors. Also, a ridge filter was fabricated to cover a large scanning area (300 × 300 mm2) by Polymethyl Methacrylate (PMMA). The fabricated ridge filter was tested at the prototype active beamline of MC-50. The SOBP and the incident beam distribution were obtained by using HD-810 GaF chromatic film placed at a right triangle to the PMMA block. The depth dose profile for the SOBP can be obtained precisely by using the flat field correction and measuring the 2-dimensional distribution of the incoming beam. After the flat field correction is used, the experimental results show that the SOBP region matches with design requirement well, with 0.62% uniformity.
On the 252Cf primary and secondary gamma rays and epithermal neutron flux for BNCT
Ghassoun, J.; Merzouki, A.; El Morabiti, A.; Jehouani, A.
2007-10-01
Monte Carlo simulation has been used to calculate the different components of neutrons and secondary gamma rays originated by 252Cf fission and also the primary gamma rays emitted directly by the 252Cf source at the exit face of a compact system designed for the BNCT. The system consists of a 252Cf source and a moderator/reflector/filter assembly. To study the material properties and configuration possibilities, the MCNP code has been used. The moderator/reflector/filter arrangement is optimised to moderate neutrons to epithermal energy and, as far as possible, to get rid of fast and thermal neutrons and photons from the therapeutic beam. To reduce the total gamma contamination and to have a sufficiently high epithermal neutron flux we have used different photon filters of different thickness. Our analysis showed that the use of an appropriate filter leads to a gamma ray flux reduction without affecting the epithermal neutron beam quality at the exit face of the system.
On the {sup 252}Cf primary and secondary gamma rays and epithermal neutron flux for BNCT
Energy Technology Data Exchange (ETDEWEB)
Ghassoun, J. [LPTN, Departement de Physique, Faculte des Sciences Semlalia, BP 2390, 40000 Marrakech (Morocco)], E-mail: ghassoun@ucam.ac.ma; Merzouki, A. [LPTN, Departement de Physique, Faculte des Sciences Semlalia, BP 2390, 40000 Marrakech (Morocco); Remote Sensing and Geomatics of the Environnement Laboratory, Ottawa-Carleton Geoscience Centre, Marion Hall-140Louis Pasteur Ottawa, ON, KIN 6N5 (Canada); El Morabiti, A.; Jehouani, A. [LPTN, Departement de Physique, Faculte des Sciences Semlalia, BP 2390, 40000 Marrakech (Morocco)
2007-10-15
Monte Carlo simulation has been used to calculate the different components of neutrons and secondary gamma rays originated by {sup 252}Cf fission and also the primary gamma rays emitted directly by the {sup 252}Cf source at the exit face of a compact system designed for the BNCT. The system consists of a {sup 252}Cf source and a moderator/reflector/filter assembly. To study the material properties and configuration possibilities, the MCNP code has been used. The moderator/reflector/filter arrangement is optimised to moderate neutrons to epithermal energy and, as far as possible, to get rid of fast and thermal neutrons and photons from the therapeutic beam. To reduce the total gamma contamination and to have a sufficiently high epithermal neutron flux we have used different photon filters of different thickness. Our analysis showed that the use of an appropriate filter leads to a gamma ray flux reduction without affecting the epithermal neutron beam quality at the exit face of the system.
On the 252Cf primary and secondary gamma rays and epithermal neutron flux for BNCT
International Nuclear Information System (INIS)
Monte Carlo simulation has been used to calculate the different components of neutrons and secondary gamma rays originated by 252Cf fission and also the primary gamma rays emitted directly by the 252Cf source at the exit face of a compact system designed for the BNCT. The system consists of a 252Cf source and a moderator/reflector/filter assembly. To study the material properties and configuration possibilities, the MCNP code has been used. The moderator/reflector/filter arrangement is optimised to moderate neutrons to epithermal energy and, as far as possible, to get rid of fast and thermal neutrons and photons from the therapeutic beam. To reduce the total gamma contamination and to have a sufficiently high epithermal neutron flux we have used different photon filters of different thickness. Our analysis showed that the use of an appropriate filter leads to a gamma ray flux reduction without affecting the epithermal neutron beam quality at the exit face of the system
Design of switched-capacitor filter circuits using low gain amplifiers
Serra, Hugo Alexandre de Andrade
2015-01-01
This book describes the design of switched-capacitor filter circuits using low gain amplifiers and demonstrates some techniques that can minimize the effects of parasitic capacitances during the design phase. Focus is given in the design of low-pass and band-pass SC filters, and how higher order filters can be achieved using cascaded biquadratic filter sections. The authors also describe a low voltage implementation of a low-pass SC filter.
INEL BNCT research program: Annual report, 1995
Energy Technology Data Exchange (ETDEWEB)
Venhuizen, J.R. [ed.
1996-04-01
This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory (INEL) Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1995. Contributions from the principal investigators about their individual projects are included, specifically, physics (treatment planning software, real-time neutron beam measurement dosimetry), and radiation biology (large animal models efficacy studies). Design of a reactor based epithermal neutron extraction facility is discussed in detail. Final results of boron magnetic resonance imagining is included for both borocaptate sodium (BSH) and boronophenylalanine (BPA) in rats, and BSH in humans. Design of an epithermal neutron facility using electron linear accelerators is presented, including a treatise on energy removal from the beam target. Information on the multiple fraction injection of BSH in rats is presented.
INEL BNCT research program: Annual report, 1995
International Nuclear Information System (INIS)
This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory (INEL) Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1995. Contributions from the principal investigators about their individual projects are included, specifically, physics (treatment planning software, real-time neutron beam measurement dosimetry), and radiation biology (large animal models efficacy studies). Design of a reactor based epithermal neutron extraction facility is discussed in detail. Final results of boron magnetic resonance imagining is included for both borocaptate sodium (BSH) and boronophenylalanine (BPA) in rats, and BSH in humans. Design of an epithermal neutron facility using electron linear accelerators is presented, including a treatise on energy removal from the beam target. Information on the multiple fraction injection of BSH in rats is presented
Dynamical decoupling sequence construction as a filter-design problem
Biercuk, M J
2010-01-01
Over the past decade we have seen an explosion of demonstrations of quantum coherence in atomic, optical, and condensed matter systems. These developments have placed a new emphasis on the production of robust and optimal quantum control techniques in the presence of environmental noise. We discuss the use of dynamical decoupling as a form of open-loop quantum control capable of suppressing the effects of decoherence in quantum coherent systems. We introduce the concept of dynamical decoupling pulse-sequence construction as a filter-design problem, making connections with radiofrequency filter design from electrical engineering in the analysis of pulse-sequence performance. Our work takes this perspective in addressing both "standard" sequences derived from nuclear magnetic resonance and novel optimized sequences developed in the context of quantum information. We describe the physics underlying the functionality of various sequences, and compare their relative capabilities. Additionally, we review new techni...
Lee, Woong-Bi; Kim, Cheolsun; Ju, Gun Wu; Lee, Yong Tak; Lee, Heung-No
2016-05-01
Miniature spectrometers have been widely developed in various academic and industrial applications such as bio-medical, chemical and environmental engineering. As a family of spectrometers, optical filter-array based spectrometers fabricated using CMOS or Nano technology provide miniaturization, superior portability and cost effectiveness. In filterarray based spectrometers, the resolution which represents the ability how closely resolve two neighboring spectra, depends on the number of filters and the characteristics of the transmission functions (TFs) of the filters. In practice, due to the small-size and low-cost fabrication, the number of filters is limited and the shape of the TF of each filter is nonideal. As a development of modern digital signal processing (DSP), the spectrometers are equipped with DSP algorithms not only to alleviate distortions due to unexpected noise or interferences among filters but also reconstruct the original signal spectrum. For a high-resolution spectrum reconstruction by the DSP, the TFs of the filters need to be sufficiently uncorrelated with each other. In this paper, we present a design of optical thin-film filters which have the uncorrelated TFs. Each filter consists of multiple layers of high- and low-refractive index materials deposited on a substrate. The proposed design helps the DSP algorithm to improve resolution with a small number of filters. We demonstrate that a resolution of 5 nm within a range from 500 nm to 1100 nm can be achieved with only 64 filters.
Institute of Scientific and Technical Information of China (English)
XIE Xuemei
2007-01-01
In this paper, a method is proposed to construct recombination nonuniform cosine-modulated filter banks (CMFBs)with a perfect-reconstruction property and with arbitrary filter lengths. In this filter bank (FB) structure, certain channels of an original M-channel uniform FB are merged by a set of transmultiplexers (TMUXs), yielding nonuniform outputs, and the length restrictions on the original CMFB and the recombination TMUXs are avoided, allowing them to have arbitrary filter lengths. By imposing certain improved matching conditions on the prototype filters, nonuniform FBs with arbitrary filter lengths and with good properties can be obtained.As a result, the flexibility of selecting modulation types and filter lengths is greatly increased in the design of recombination nonuniform CMFBs. Another benefit due to the flexibility is that the system delay can be reduced.
A feasibility study of the Tehran research reactor as a neutron source for BNCT
International Nuclear Information System (INIS)
Investigation on the use of the Tehran Research Reactor (TRR) as a neutron source for Boron Neutron Capture Therapy (BNCT) has been performed by calculating and measuring energy spectrum and the spatial distribution of neutrons in all external irradiation facilities, including six beam tubes, thermal column, and the medical room. Activation methods with multiple foils and a copper wire have been used for the mentioned measurements. The results show that (1) the small diameter and long length beam tubes cannot provide sufficient neutron flux for BNCT; (2) in order to use the medical room, the TRR core should be placed in the open pool position, in this situation the distance between the core and patient position is about 400 cm, so neutron flux cannot be sufficient for BNCT; and (3) the best facility which can be adapted for BNCT application is the thermal column, if all graphite blocks can be removed. The epithermal and fast neutron flux at the beginning of this empty column are 4.12×109 and 1.21×109 n/cm2/s, respectively, which can provide an appropriate neutron beam for BNCT by designing and constructing a proper Beam Shaping Assembly (BSA) structure. - Highlights: • The feasibility of using of TRR for BNCT has been investigated. • Neutron energy spectrum at all external irradiation facilities of TRR have been measured and calculated. • Spatial distribution of neutrons have been measured using copper wire activation method
Directory of Open Access Journals (Sweden)
Sagar R. Patil
2015-11-01
Full Text Available In automobile vehicles mostly plastic molded panel filters used for the purpose of engine air filtration. Fibrous structured cellulose media were being used with different permeability’s according to requirement of rated air flow rate required for the engine. To optimize the filter pleat design of automotive panel air filter, it is important to study correlation of pressure drop, dust holding capacity & efficiency. The main role of a filter is to provide least pressure drop with high dust holding and efficiency. A channel made for the testing of different pleat designs. This research comprises of experimental design & evaluation of filter element with variable pleat depth and pleat density. This assessment offers the selection of pleat design according to the performance requirements.
Design and optimization of multipole lens and Wien filter systems
International Nuclear Information System (INIS)
The differential algebra (DA) method has been employed to compute the optical properties and aberrations up to the fifth order of multipole systems containing electrostatic and magnetic round, quadrupole, hexapole and octopole lenses, and Wien filters. A new software package has been developed, which computes the geometrical and chromatic aberrations up to the fifth order by using a single DA ray trace. It also has an optimization module where a weighted set of aberrations can be minimized by the automatic adjustment of a set of user-defined system variables. In this paper, we present our new method for designing and optimizing multipole systems including Wien filters, and illustrate its application with three relevant examples.
Combination of fractionated photon radiation and BNCT
International Nuclear Information System (INIS)
Because of the relatively low normal brain dose, BNCT allows additional photon radiation sufficient to maintain a total normal brain dose below the tolerance limit. We started a new protocol with a combination of fractionated, extended local photon radiation, and BPA- and BSH-mediated BNCT. In this protocol, newly diagnosed glioblastoma were treated with BPA (250 mg/kg) - and BSH (100 mg/kg) - mediated BNCT followed by fractionated photon radiation. The BNCT dose for the normal brain was restricted to less than 13 GyEq. The fractionated photon radiation at a dose of 30/15 fr or 30.6 Gy/17 fr was planned to irradiate a T2 high-intensity area of post-BNCT MRI. So far, 6 patients have been treated by this protocol. The clinical course, dose distribution, tumor response, and adverse events will be discussed herein. (author)
Fixed-Point Design of Generalized Comb Filters: A Statistical Approach
Laddomada, Massimiliano
2008-01-01
This paper is concerned with the problem of designing computationally efficient Generalized Comb Filters (GCF). Basically, GCF filters are anti-aliasing filters that guarantee superior performance in terms of selectivity and quantization noise rejection compared to classical comb filters, when used as decimation filters in multistage architectures. Upon employing a partial polyphase (PP) architecture proposed in a companion paper, we develop a sensitivity analysis in order to investigate the effects of the coefficients' quantization on the frequency response of the designed filters. We show that the sensitivity of the filter response to errors in the coefficients is dependent on the particular split of the decimation factor between the two sub-filters constituting the PP architecture. The sensitivity analysis is then used for developing a fixed-point implementation of a sample filter from the class of GCF filters, used as reference filter throughout the paper. Finally, we present computer simulations in order...
SkyMapper Filter Set: Design and Fabrication of Large Scale Optical Filters
Bessell, Michael; Schmidt, Brian; Keller, Stefan; Tisserand, Patrick; Francis, Paul
2011-01-01
The SkyMapper Southern Sky Survey will be conducted from Siding Spring Observatory with u, v, g, r, i and z filters that comprise glued glass combination filters of dimension 309x309x15 mm. In this paper we discuss the rationale for our bandpasses and physical characteristics of the filter set. The u, v, g and z filters are entirely glass filters which provide highly uniform band passes across the complete filter aperture. The i filter uses glass with a short-wave pass coating, and the r filter is a complete dielectric filter. We describe the process by which the filters were constructed, including the processes used to obtain uniform dielectric coatings and optimized narrow band anti-reflection coatings, as well as the technique of gluing the large glass pieces together after coating using UV transparent epoxy cement. The measured passbands including extinction and CCD QE are presented.
A geometric method for optimal design of color filter arrays.
Hao, Pengwei; Li, Yan; Lin, Zhouchen; Dubois, Eric
2011-03-01
A color filter array (CFA) used in a digital camera is a mosaic of spectrally selective filters, which allows only one color component to be sensed at each pixel. The missing two components of each pixel have to be estimated by methods known as demosaicking. The demosaicking algorithm and the CFA design are crucial for the quality of the output images. In this paper, we present a CFA design methodology in the frequency domain. The frequency structure, which is shown to be just the symbolic DFT of the CFA pattern (one period of the CFA), is introduced to represent images sampled with any rectangular CFAs in the frequency domain. Based on the frequency structure, the CFA design involves the solution of a constrained optimization problem that aims at minimizing the demosaicking error. To decrease the number of parameters and speed up the parameter searching, the optimization problem is reformulated as the selection of geometric points on the boundary of a convex polygon or the surface of a convex polyhedron. Using our methodology, several new CFA patterns are found, which outperform the currently commercialized and published ones. Experiments demonstrate the effectiveness of our CFA design methodology and the superiority of our new CFA patterns. PMID:20858581
Design Of EMI Filter For Flash Lamp Power Supply
Directory of Open Access Journals (Sweden)
Amrita Bhatt
2015-08-01
Full Text Available Abstract Conducted and radiated electromagnetic interference in embedded and VLSI systems have become important in recent years with increase in clock frequency and reduction in physical dimensions of interconnects. It is important to understand the noise components in terms of current paths and the mitigation techniques. Although the common mode and differential mode components of conducted noise are analyzed in the context of a power electronics system the analytical and theoretical techniques hold good for other domains as well such as embedded systems and VLSI. This paper deals with modelling design and development of an EMI filter for conducted mode noise in flash lamp power supply. Also a design procedure of EMI filters sustaining to the military standard 461E is presented and it is based on practical measurement of conducted emissions. Design procedure in this paper considers common mode and differential mode separately. The paper also consists of considerations for magnetic core material integrated common mode CM common mode choke size optimization and differential mode DM choke etc. Design examples are given and are experimentally verified.
AESOP- INTERACTIVE DESIGN OF LINEAR QUADRATIC REGULATORS AND KALMAN FILTERS
Lehtinen, B.
1994-01-01
AESOP was developed to solve a number of problems associated with the design of controls and state estimators for linear time-invariant systems. The systems considered are modeled in state-variable form by a set of linear differential and algebraic equations with constant coefficients. Two key problems solved by AESOP are the linear quadratic regulator (LQR) design problem and the steady-state Kalman filter design problem. AESOP is designed to be used in an interactive manner. The user can solve design problems and analyze the solutions in a single interactive session. Both numerical and graphical information are available to the user during the session. The AESOP program is structured around a list of predefined functions. Each function performs a single computation associated with control, estimation, or system response determination. AESOP contains over sixty functions and permits the easy inclusion of user defined functions. The user accesses these functions either by inputting a list of desired functions in the order they are to be performed, or by specifying a single function to be performed. The latter case is used when the choice of function and function order depends on the results of previous functions. The available AESOP functions are divided into several general areas including: 1) program control, 2) matrix input and revision, 3) matrix formation, 4) open-loop system analysis, 5) frequency response, 6) transient response, 7) transient function zeros, 8) LQR and Kalman filter design, 9) eigenvalues and eigenvectors, 10) covariances, and 11) user-defined functions. The most important functions are those that design linear quadratic regulators and Kalman filters. The user interacts with AESOP when using these functions by inputting design weighting parameters and by viewing displays of designed system response. Support functions obtain system transient and frequency responses, transfer functions, and covariance matrices. AESOP can also provide the user
Design of a Symmetrical Microstrip Bandpass Filter for S-Band Frequency Range
Mohd F. Ain; Mandeep S.J. Singh; Prabhu; Syed I. S. Hassan
2007-01-01
A new type of microstrip bandpass filter is presented with a center frequency operation at 2.5GHz which lies in the S-band frequency range. The filter is designed to be much smaller compared to the same type of parallel-coupled bandpass filter. The simulation results are excellent and the filter is suitable for integration within various microwave subsystems.
Dynamical decoupling sequence construction as a filter-design problem
Energy Technology Data Exchange (ETDEWEB)
Biercuk, M J; Doherty, A C [Centre for Engineered Quantum Systems, School of Physics, University of Sydney, NSW 2006 (Australia); Uys, H, E-mail: michael.biercuk@sydney.edu.au, E-mail: andrew.doherty@sydney.edu.au, E-mail: huys@csir.co.za [National Laser Centre, Council for Scientific and Industrial Research, Pretoria (South Africa)
2011-08-14
Over the past decade we have seen an explosion of demonstrations of quantum coherence in atomic, optical and condensed matter systems. These developments have placed a new emphasis on the production of robust and optimal quantum control techniques in the presence of environmental noise. We discuss the use of dynamical decoupling as a form of open-loop quantum control capable of suppressing the effects of dephasing in quantum coherent systems. We introduce the concept of dynamical decoupling pulse-sequence construction as a filter-design problem, making connections with filter design from control theory and electrical engineering in the analysis of pulse-sequence performance for the preservation of the phase degree of freedom in a quantum superposition. A detailed mathematical description of how dephasing and its suppression can be reduced to a linear control problem is provided, and used as motivation and context for studies of the filtration properties of various dynamical decoupling sequences. Our work then takes this practical perspective in addressing both 'standard' sequences derived from nuclear magnetic resonance and novel optimized sequences developed in the context of quantum information. Additionally, we review new techniques for the numerical construction of optimized pulse sequences in this light. We show how the filter-design perspective permits concise comparisons of the relative capabilities of these sequences and reveals the physics underlying their functionality. The use of this new analytical framework allows us to derive new insights into the performance of these sequences and reveals important limiting issues, such as the effect of digital clocking on optimized sequence performance.
Dynamical decoupling sequence construction as a filter-design problem
International Nuclear Information System (INIS)
Over the past decade we have seen an explosion of demonstrations of quantum coherence in atomic, optical and condensed matter systems. These developments have placed a new emphasis on the production of robust and optimal quantum control techniques in the presence of environmental noise. We discuss the use of dynamical decoupling as a form of open-loop quantum control capable of suppressing the effects of dephasing in quantum coherent systems. We introduce the concept of dynamical decoupling pulse-sequence construction as a filter-design problem, making connections with filter design from control theory and electrical engineering in the analysis of pulse-sequence performance for the preservation of the phase degree of freedom in a quantum superposition. A detailed mathematical description of how dephasing and its suppression can be reduced to a linear control problem is provided, and used as motivation and context for studies of the filtration properties of various dynamical decoupling sequences. Our work then takes this practical perspective in addressing both 'standard' sequences derived from nuclear magnetic resonance and novel optimized sequences developed in the context of quantum information. Additionally, we review new techniques for the numerical construction of optimized pulse sequences in this light. We show how the filter-design perspective permits concise comparisons of the relative capabilities of these sequences and reveals the physics underlying their functionality. The use of this new analytical framework allows us to derive new insights into the performance of these sequences and reveals important limiting issues, such as the effect of digital clocking on optimized sequence performance.
Dynamical decoupling sequence construction as a filter-design problem
Biercuk, M. J.; Doherty, A. C.; Uys, H.
2011-08-01
Over the past decade we have seen an explosion of demonstrations of quantum coherence in atomic, optical and condensed matter systems. These developments have placed a new emphasis on the production of robust and optimal quantum control techniques in the presence of environmental noise. We discuss the use of dynamical decoupling as a form of open-loop quantum control capable of suppressing the effects of dephasing in quantum coherent systems. We introduce the concept of dynamical decoupling pulse-sequence construction as a filter-design problem, making connections with filter design from control theory and electrical engineering in the analysis of pulse-sequence performance for the preservation of the phase degree of freedom in a quantum superposition. A detailed mathematical description of how dephasing and its suppression can be reduced to a linear control problem is provided, and used as motivation and context for studies of the filtration properties of various dynamical decoupling sequences. Our work then takes this practical perspective in addressing both 'standard' sequences derived from nuclear magnetic resonance and novel optimized sequences developed in the context of quantum information. Additionally, we review new techniques for the numerical construction of optimized pulse sequences in this light. We show how the filter-design perspective permits concise comparisons of the relative capabilities of these sequences and reveals the physics underlying their functionality. The use of this new analytical framework allows us to derive new insights into the performance of these sequences and reveals important limiting issues, such as the effect of digital clocking on optimized sequence performance.
TL detectors in BNCT dosimetry
International Nuclear Information System (INIS)
The main detectors for characterising and controlling of BNCT beams are activation foils and paired ionisation chambers. Thermoluminescent (TL) dosimeters are also of interest because of their following advantages: i) small physical size, ii) no need for high voltage or cables, i.e. stand alone character, and iii) suitability for large scale measurements; with TL dosimeters it is possible to measure depth dose curves and profiles at the same time, with one irradiation. Also, TL dosimeters may be possible detectors for in vivo use. At the Finnish BNCT facility, a TL detector MTS-Ns of TLD Niewiadomski and Co. (Krakow, Poland) with an ultrathin active LiF:Mg,Ti layer for small self-shielding of thermal neutrons was selected for use as a neutron sensitive dosimeter. A TL detector MCP-7s (7LiF:Mg,Cu,P) of the same manufacturer was used for gamma detection because of its high sensitivity to gamma radiation compared to that to high LET radiation. The gamma dose and neutron fluence distributions have been measured in PMMA, water and brain substitute liquid phantoms at the BNCT beam. Gamma dose and neutron fluence profiles measured with TL detectors correlate with those calculated using DORT (Two Dimensional Discrete Ordinates Transport Code) and measured with ionisation chambers. NITS-Ns TL detectors were found to measure accurately (8%, 1 S.D.) the relative neutron fluence, and therefore to be a useful addition to the activation foils in BNCT neutron dosimetry. Due to the high uncertainty of the thermal neutron sensitivity of the MCP-7s TL detectors, the absorbed gamma doses can be measured with MCP-7s detectors within 20% in the mixed neutron-gamma field of BNCT. The treatments of glioma patients at the Finnish BNCT facility will start in the spring 1999. The doses to the target volume and sensitive organs, i.e. brain, will be calculated individually in the dose planning. Since it is also necessary to monitor the absorbed doses to the head and to the body, in vivo
International Nuclear Information System (INIS)
An accelerator-based BNCT (Boron Neutron Capture Therapy) facility is being constructed at the Ibaraki Neutron Medical Research Center. It consists of a proton linac (8 MeV energy and 10 mA average current), a beryllium target, and a moderator system to provide an epi-thermal neutron flux for patient treatment. The technology choices for this present system were driven by the need to site the facility in a hospital and where low residual activity is essential. The maximum neutron energy produced from an 8 MeV-proton is 6 MeV, which is below the threshold energy of the main nuclear reactions which produce radioactive products. The down side of this technology choice is that it produces a high density heat load on the target so that cooling and hydrogen blistering amelioration prevent sever challenges requiring successful R and D progress. The latest design of the target and moderator system shows that a flux of 2.5x109 epi-thermal neutrons/cm2/sec can be obtained. This is two times higher than the flux from the existing nuclear reactor based BNCT facility at JAEA (JRR-4). (author)
A Practical Design of Lumped, Semi-lumped & Microwave Cavity Filters
Natarajan, Dhanasekharan
2013-01-01
This book presents the application of microwave literature for designing lumped/semi-lumped filters and combline/iris-coupled microwave cavity filters. It provides the physical understanding of the terms and characteristics of radio frequency (RF) filters. The book complements engineering text books on RF components and provides support for the project assignments of students. In addition to the functional design of RF filters, the integrated design approach for produceability and reliability is explained.
Design of Low Pass Digital FIR Filter Using Cuckoo Search Algorithm
Directory of Open Access Journals (Sweden)
Taranjit Singh
2014-08-01
Full Text Available This paper presents a novel approach of designing linear phase FIR low pass filter using cuckoo Search Algorithm (CSA. FIR filter design is a multi-modal optimization problem. The conventional optimization techniques are not efficient for digital filter design. An iterative method is introduced to find the best solution of FIR filter design problem.Flat passband and high stopband attenuation are the major characteristics required in FIR filter design. To achieve these characteristics, a Cuckoo Search algorithm (CSA is proposed in this paper. CSA have been used here for the design of linear phase finite impulse response (FIR filters. Results are presented in this paper that seems to be promising tool for FIR filter design
Implementation of BNCT treatment planning procedures
International Nuclear Information System (INIS)
Estimation of radiation doses delivered during boron neutron capture therapy (BNCT) requires combining data on spatial distribution of both the thermal neutron fluence and the 10B concentration, as well as the relative biological effectiveness of various radiation dose components in the tumor and normal tissues. Using the treatment planning system created at Idaho National Engineering and Environmental Laboratory and the procedures we had developed for clinical trials, we were able to optimize the treatment position, safely deliver the prescribed BNCT doses, and carry out retrospective analyses and reviews. In this paper we describe the BNCT treatment planning process and its implementation in the ongoing dose escalation trials at Brookhaven National Laboratory. (author)
Energy Technology Data Exchange (ETDEWEB)
Stella, S.; Bazani, A.; Ballarini, F.; Bortolussi, S.; Protti, N.; Altieri, S. [Department of Nuclear and Theoretical Physics, University of Pavia (Italy); Istituto Nazionale di Fisica Nucleare (INFN), Section of Pavia (Italy); Bruschi, P. [Department of Nuclear and Theoretical Physics, University of Pavia (Italy)
2011-07-01
In preclinical and clinical Boron Neutron Capture Therapy studies the knowledge of the amount of {sup 10}B in blood and tissues is very important. The boron concentration measurements method used in Pavia (Italy) is based on the charged particles spectrometry of thin tissue cuts irradiated in the Thermal Column of the TRIGA reactor of the University. In order to perform measurements in biological liquids such as blood and urine, or in other tissue that cannot be cut in slices, a Prompt Gamma Neutron Activation Analysis (PGNAA) facility is being designed, which measures {sup 10}B concentration detecting the prompt gamma from boron nuclear capture reaction. At the TRIGA reactor in Pavia, there are four horizontal channels, potentially available for PGNAA. The choice of the suitable channel, and the design of its configuration, were achieved using the Monte Carlo neutron transport code MCNP4c2. To perform the simulations, an input code already validated, describing the reactor structure and the neutron source, was used. The calculations were implemented applying non-analog techniques for the neutron transport, that are necessary to obtain a sufficient statistic in every positions along the channel and especially at its end. The selection of the channel for PGNAA installation was carried out by comparing the simulated fluxes obtained in the different channels at the present configuration. The channel shielded by the core reflector was chosen, because the graphite lowers the fast component of the neutrons, with no need to insert additional material in the facility. The thermal flux at its end is 1.7 x 10{sup 8} n/cm{sup 2} s with thermal-to-total neutron flux ratio around 0.8. Subsequently a bismuth block for gamma radiation shielding and blocks of single crystal sapphire as filter for fast neutron component were inserted in the channel. Other components of the facility that are under study are a collimator and the beam catcher. (author)
Modernization of sump filters design on ROVNO NPP
International Nuclear Information System (INIS)
Taking into account the major importance to solve sump plugging in case of primary break, modernization of sump filters design on ROVNO NPP has been engaged. This action has been realized using a > approach, which had been proposed by the Commission of the European Community (CEC) in 1998, with the purpose of effectiveness increase of activities under realization of TACIS program projects. This paper gives a short summary of the different actions performed by the Technical Support Organization (IRSN, France), the State Scientific and Technical Center for Nuclear and Radiation Safety (SSTC NRS, Ukraine), the State Nuclear Regulatory Committee of Ukraine (SNRCU), the ROVNO NPP, assisted by EDF and the designer (FORTUM and FRAMATOME). (authors)
Gabor Filter Optimization Design for Iris Texture Analysis
Institute of Scientific and Technical Information of China (English)
Tao Xu; Xing Ming; Xiaoguang Yang
2004-01-01
This paper deals with an optimization design method for the Gabor filters based on the analysis of an iris texture model. By means of analyzing the properties of an iris texture image, the energy distribution regularity of the iris texture image measured by the average power spectrum density is exploited, and the theoretical ranges of the efficient valued frequency and orientation parameters can also be deduced. The analysis shows that the energy distribution of the iris texture is generally centralized around lower frequencies in the spatial frequency domain. Accordingly, an iterative algorithm is designed to optimize the Gabor parameter field. The experimental results indicate the validity of the theory and efficiency of the algorithm.
Design of the LC+trap filter for a current source rectifier
DEFF Research Database (Denmark)
Min, Huang; Wang, Xiongfei; Loh, Poh Chiang; Blaabjerg, Frede
2015-01-01
capacitor voltage and the line current THD for space vector modulation. The resonance of the input filter can be excited by the Pulse Width Modulation (PWM) and a simple passive damping can damp the resonances. The analysis and design of the input filter have been verified by simulations in MATLAB/Simulink.......This paper investigates an LC + trap filter for current source converters to improve the switching harmonic attenuation. The resonant frequency characteristics of the filter of current source rectifier are analyzed. A filter design procedure is proposed based on the input power factor, filter...
Measurement and simulation of the TRR BNCT beam parameters
Bavarnegin, Elham; Sadremomtaz, Alireza; Khalafi, Hossein; Kasesaz, Yaser; Golshanian, Mohadeseh; Ghods, Hossein; Ezzati, Arsalan; Keyvani, Mehdi; Haddadi, Mohammad
2016-09-01
Recently, the configuration of the Tehran Research Reactor (TRR) thermal column has been modified and a proper thermal neutron beam for preclinical Boron Neutron Capture Therapy (BNCT) has been obtained. In this study, simulations and experimental measurements have been carried out to identify the BNCT beam parameters including the beam uniformity, the distribution of the thermal neutron dose, boron dose, gamma dose in a phantom and also the Therapeutic Gain (TG). To do this, the entire TRR structure including the reactor core, pool, the thermal column and beam tubes have been modeled using MCNPX Monte Carlo code. To measure in-phantom dose distribution a special head phantom has been constructed and foil activation techniques and TLD700 dosimeter have been used. The results show that there is enough uniformity in TRR thermal BNCT beam. TG parameter has the maximum value of 5.7 at the depth of 1 cm from the surface of the phantom, confirming that TRR thermal neutron beam has potential for being used in treatment of superficial brain tumors. For the purpose of a clinical trial, more modifications need to be done at the reactor, as, for example design, and construction of a treatment room at the beam exit which is our plan for future. To date, this beam is usable for biological studies and animal trials. There is a relatively good agreement between simulation and measurement especially within a diameter of 10 cm which is the dimension of usual BNCT beam ports. This relatively good agreement enables a more precise prediction of the irradiation conditions needed for future experiments.
DESIGN OF STEPPED IMPEDANCE LOW PASS FILTER AT 2.4GHz
Vishakha Dayal Shrivastava*, Vandana Vikas Thakare
2016-01-01
In this era, life can't be envisioned without wireless communication. The microwave filter is a component which gives frequency selectivity in mobile, radar, satellite communication systems working at microwave frequency. Microwave low pass filter attenuates the unwanted signal above cut off frequency. For stepped impedance filter design high and low impedance lines are used. This paper describes designing of Chebyshev approximated stepped impedance low pass filter at 2.4 GHz with t...
Design and analysis of microstrip photonic band gap filter without etching ground plane
R. N. Baral; P. K. Singhal
2009-01-01
A design of microstrip photonic band gap (PBG) filter is presented in this paper. The band reject filter is compact in structure and provides accurate band gap. The proposed filter has a periodic configuration; the impedance distribution over the length of each period is varied according to a designated sinusoidal function. Both theoretical and experimental results indicate that a bandstop filter with an extremely wide bandwidth can be achieved. Detailed analysis of the frequency response of ...
Criteria for calculating the efficiency of HEPA filters during and after design basis accidents
International Nuclear Information System (INIS)
We have reviewed the literature on the performance of high efficiency particulate air (HEPA) filters under normal and abnormal conditions to establish criteria for calculating the efficiency of HEPA filters in a DOE nonreactor nuclear facility during and after a Design Basis Accident (DBA). The literature review included the performance of new filters and parameters that may cause deterioration in the filter performance such as filter age, radiation, corrosive chemicals, seismic and rough handling, high temperature, moisture, particle clogging, high air flow and pressure pulses. The deterioration of the filter efficiency depends on the exposure parameters; in severe exposure conditions the filter will be structurally damaged and have a residual efficiency of 0%. Despite the many studies on HEPA filter performance under adverse conditions, there are large gaps and limitations in the data that introduce significant error in the estimates of HEPA filter efficiencies under DBA conditions. Because of this limitation, conservative values of filter efficiency were chosen when there was insufficient data
USING GENETIC ALGORITHMS FOR DESIGNING OF FIR DIGITAL FILTERS
Directory of Open Access Journals (Sweden)
Alireza Rezaee
2010-07-01
Full Text Available In this paper, a new technique is presented for the design and optimization of digital FIR filters with coefficients that are presented in canonic signed-digit (CSD format. Since such implementation requires no multipliers, it reduces the hardware cost and lowers the power consumption. The proposed technique considers three goals, the optimum number of coefficients, the optimum wordlength, and the optimum set of coefficients which satisfies the desirable frequency response and ensures the minimum hardware cost by minimizing the number of nonzero digits in CSD representation of the coefficients using Genetic Algorithms (GA. Comparing with equiripple method, the proposed technique results in about 30-40 percent reduction in hardware cost.
Design of Reversible Multipliers for Linear Filtering Applications in DSP
Directory of Open Access Journals (Sweden)
Rakshith Saligram
2013-01-01
Full Text Available Multipliers in DSP computations are crucial. Thus modern DSP systems need to develop low powermultipliers to reduce the power dissipation. One of the efficient ways to reduce power dissipation is by theuse of bypassing technique. If a bit in the multiplier and/or multiplicand is zero the whole array of rowand/or diagonal will be bypassed and hence the name bypass multipliers. This paper presents the columnBypass multiplier and 2-D bypass multiplier using reversible logic; Reversible logic is a more prominenttechnology, having its applications in Low Power CMOS and quantum computations. The switchingactivity of any component in the bypass multiplier depends only on the input bit coefficients. Thesemultipliers find application in linear filtering FFT computational units, particularly during zero paddingwhere there will be umpteen numbers of zeros. A bypass multiplier reduces the number of switchingactivities as well as the power consumption, above which reversible logic design acts to further almostnullify the dissipations
Hydraulic design optimization for hollow fiber filter system
International Nuclear Information System (INIS)
An analytical model has been developed to describe hydraulic characteristics of a hollow fiber membrane filter (HFF) for condensate purification in BWR power plants. Using this model, a module structure was proposed to minimize pressure drop at the beginning of HFF operation. That is, given flow rate of a module, both dimensions of the inner diameter and the length of a single fiber membrane were designed to have optimal values, giving minimum volume for the module. The mechanism of Fe ion crystallization on HFF surface which determines operation life time was clarified and a countermeasure against it was developed. Precoating of amorphous iron crud effectively inhibited crystallization. Taking account of the crystallization, a simulation code was developed to predict pressure drop trend in the course of HFF operation. (author)
Characterisation of an accelerator-based neutron source for BNCT versus beam energy
Agosteo, S; D'Errico, F; Nath, R; Tinti, R
2002-01-01
Neutron capture in sup 1 sup 0 B produces energetic alpha particles that have a high linear energy transfer in tissue. This results in higher cell killing and a higher relative biological effectiveness compared to photons. Using suitably designed boron compounds which preferentially localize in cancerous cells instead of healthy tissues, boron neutron capture therapy (BNCT) has the potential of providing a higher tumor cure rate within minimal toxicity to normal tissues. This clinical approach requires a thermal neutron source, generally a nuclear reactor, with a fluence rate sufficient to deliver tumorcidal doses within a reasonable treatment time (minutes). Thermal neutrons do not penetrate deeply in tissue, therefore BNCT is limited to lesions which are either superficial or otherwise accessible. In this work, we investigate the feasibility of an accelerator-based thermal neutron source for the BNCT of skin melanomas. The source was designed via MCNP Monte Carlo simulations of the thermalization of a fast ...
Clinical results of BNCT for malignant meningiomas
International Nuclear Information System (INIS)
Malignant meningiomas is difficult pathology to be controlled as well as GBM. Since June of 2005, we applied BNCT for 7 cases of malignancy related meningiomas with 13 times neutron irradiation. Five were anaplastic, one was atypical meningiomas and one was sarcoma transformed from meningioma with cervical lymph node metastasis. All cases were introduced after repetitive surgeries and XRT or SRS. Follow-up images were available for 6 cases with observation duration between 2 to 9 months. We applied F-BPA-PET before BNCT in 6 out of 7 cases. One case was received methionine-PET. Five out of 6 cases who received BPA-PET study showed good BPA uptake more than 3 of T/N ratio. One atypical meningiomas cases showed 2.0 of T/N ratio. Original tumor sizes were between 9.2 to 92.7 ml. Two out of 5 anaplastic meningiomas showed CR and all six cases showed radiographic improvements. Clinical symptoms before BNCT such as hemiparesis and facial pain were improved after BNCT, except one case. An huge atypical meningiomas which arisen from tentorium and extended bilateral occipital lobes and brain stem, visual problems were worsened after repetitive BNCT with increase of peritumoral edema. Malignant meningiomas are seemed to be good candidate for BNCT. (author)
Feasibility study of using laser-generated neutron beam for BNCT
International Nuclear Information System (INIS)
The feasibility of using a laser-accelerated proton beam to produce a neutron source, via (p,n) reaction, for Boron Neutron Capture Therapy (BNCT) applications has been studied by MCNPX Monte Carlo code. After optimization of the target material and its thickness, a Beam Shaping Assembly (BSA) has been designed and optimized to provide appropriate neutron beam according to the recommended criteria by International Atomic Energy Agency. It was found that the considered laser-accelerated proton beam can provide epithermal neutron flux of ∼2×106 n/cm2 shot. To achieve an appropriate epithermal neutron flux for BNCT treatment, the laser must operate at repetition rates of 1 kHz, which is rather ambitious at this moment. But it can be used in some BNCT researches field such as biological research. - Highlights: • Feasibility of using laser-accelerated proton beam for BNCT has been investigated. • The considered beam can provide epithermal neutron flux of ~2×106 (n/cm2.shot). • For BNCT treatment, the laser must operate at repetition rates of 1 kHz
Design a Micro-Strip Band Pass Filter for 6 GHz
Ashish Duvey
2012-01-01
Purpose of this paper described about the design of microwave band pass filter by using microstrip layout. A microwave filter is two port network used to control the frequency response. The developments after micro-strip filter are simulated by using IE3D simulator software. Photolithographic process is used for fabrication and after fabrication final testing had done by using the spectrum analyzer.
Design of digital trapezoidal shaping filter based on LabVIEW
International Nuclear Information System (INIS)
It describes the design of a digital trapezoidal shaping filter to nuclear signals based on LabVIEW. A method of optimizing the trapezoidal shaping filter's parameters was presented and tested, and the test results of the effect of shaping filter algorithm were studied. (authors)
Energy Technology Data Exchange (ETDEWEB)
Masoudi, S. Farhad, E-mail: masoudi@kntu.ac.ir; Rasouli, Fatemeh S.
2015-08-01
Recent studies in BNCT have focused on investigating appropriate neutron sources as alternatives for nuclear reactors. As the most prominent facilities, the electron linac based photoneutron sources benefit from two consecutive reactions, (e, γ) and (γ, n). The photoneutron sources designed so far are composed of bipartite targets which involve practical problems and are far from the objective of achieving an optimized neutron source. This simulation study deals with designing a compact, optimized, and geometrically simple target for a photoneutron source based on an electron linac. Based on a set of MCNPX simulations, tungsten is found to have the potential of utilizing as both photon converter and photoneutron target. Besides, it is shown that an optimized dimension for such a target slows-down the produced neutrons toward the desired energy range while keeping them economy, which makes achieving the recommended criteria for BNCT of deep-tumors more available. This multi-purpose target does not involve complicated designing, and can be considered as a significant step toward finding application of photoneutron sources for in-hospital treatments. In order to shape the neutron beam emitted from such a target, the beam is planned to pass through an optimized arrangement of materials composed of moderators, filters, reflector, and collimator. By assessment with the recommended in-air parameters, it is shown that the designed beam provides high intensity of desired neutrons, as well as low background contamination. The last section of this study is devoted to investigate the performance of the resultant beam in deep tissue. A typical simulated liver tumor, located within a phantom of human body, was subjected to the irradiation of the designed spectrum. The dosimetric results, including evaluated depth-dose curves and carried out in-phantom parameters show that the proposed configuration establishes acceptable agreement between the appropriate neutron intensity, and
On the Polyphase Decomposition for Design of Generalized Comb Decimation Filters
Laddomada, Massimiliano
2007-01-01
Generalized comb filters (GCFs) are efficient anti-aliasing decimation filters with improved selectivity and quantization noise (QN) rejection performance around the so called folding bands with respect to classical comb filters. In this paper, we address the design of GCF filters by proposing an efficient partial polyphase architecture with the aim to reduce the data rate as much as possible after the Sigma-Delta A/D conversion. We propose a mathematical framework in order to completely char...
Intelligent Optimize Design of LCL Filter for Three-Phase Voltage-Source PWM Rectifier
DEFF Research Database (Denmark)
Sun, Wei; Chen, Zhe; Wu, Xiaojie
2009-01-01
Compared to traditional L filter, a LCL filter is more effective on reducing harmonic distortion at switch frequency. So it is important to choose the LCL filter parameters to achieve good filtering effect. This paper introduces some traditional design methods. Design of a LCL filter by genetic...... algorithm (GA) and particle swam optimization (PSO) are presented in this paper and comparison of the two intelligent optimization. Simulation result and calculate data are provided to prove that intelligent optimization are more effective and simple than traditional methods....
Design of Miniaturized Multiband Filters Using Zero Order Resonators for WLAN Applications
Directory of Open Access Journals (Sweden)
Maryam Shafiee
2015-01-01
Full Text Available The objective of this paper is to design miniaturized narrow- and dual-band filters for WLAN application using zero order resonators by the method of least squares. The miniaturization of the narrow-band filter is up to 70% and that of the dual-band filter is up to 64% compared to the available models in the literature. Two prototype models of the narrow-band and dual-band filters are fabricated and measured, which verify the proposed structure for the filter and its design by the presented method, using an equivalent circuit model.
The experience from the construction of BNCT facility at the LVR-15 reactor
International Nuclear Information System (INIS)
The BNCT project at LVR-15 reactor of NRI for treatment of human brain gliomas is before start of clinical trials. A survey of present conditions is included, the attention is devoted to BNCT facility with epithermal neutron beam first of all. The different materials for filter composition were studied, the calculational methods have been used for the determination of neutron and gamma rays in the reactor geometry. Some configurations were experimentally verified. The effort for improvement of epithermal neutron beam parameters in configuration 1998 was concentrated to block of filters remodelling, improvement of collimator-shutter geometry, the choice of optimal reactor core edge configuration. Awaited results from experiment in June 1999 are described. (author)
The Design of Polymer Planar Optical Triplexer with MMI Filter and Directional Coupler
Directory of Open Access Journals (Sweden)
V. Jerabek
2013-12-01
Full Text Available Optical bidirectional WDM transceiver is a key component of the Passive Optical Network of the Fiber to the Home topology. Essential parts of such transceivers are filters that combine multiplexing and demultiplexing function of optical signal (triplexing filters. In this paper we report about a design of a new planar optical multi-wavelength selective system triplexing filter, which combines a multimode interference filter with directional coupler based on the epoxy polymer SU-8 on Si/SiO2 substrate. The optical triplexing filter was designed using the Beam Propagation Method. The aim of this project was to optimize the triplexing filter optical parameters and to minimize the planar optical wavelength selective system dimensions. The multimode interference filter was used for separation of downstream optical signal in designed optoelectronic integrated WDM transceiver. The directional coupler was used for adding of upstream optical signal.
A Proficient Design of Hybrid Synchronous and Asynchronous Digital FIR Filter using FPGA
Directory of Open Access Journals (Sweden)
B.Paulchamy
2012-07-01
Full Text Available In this paper, a hybrid synchronous and asynchronous digital FIR filter is designed and implemented in FPGA using VHDL. The digital FIR filter of high throughput, low latency operating at above 1.3 GHz was designed. An adaptive high capacity pipelined was introduced in the hybrid synchronous asynchronous design of the filter. The degree of the pipelining is dynamically variable depending upon the input. Concurrent execution of software or program can be achieved in FPGA through parallel processing. The designed digital FIR filter is simulated using ModelSim and implemented using Xilinx. The simulation results are presented for different order such as 3, 6 and 15. The FIR filter designed is synthesized in Xilinx 9.1i and the device utilization report is presented for filter of order 3, 6 and 15.
Interpolation Filter Design for Hearing-Aid Audio Class-D Output Stage Application
DEFF Research Database (Denmark)
Pracný, Peter; Bruun, Erik; Muntal, Pere Llimós
2012-01-01
This paper deals with a design of a digital interpolation filter for a 3rd order multi-bit ΣΔ modulator with over-sampling ratio OSR = 64. The interpolation filter and the ΣΔ modulator are part of the back-end of an audio signal processing system in a hearing-aid application. The aim in this paper...... is to compare this design to designs presented in other state-of-the-art works ranging from hi-fi audio to hearing-aids. By performing comparison, trends and tradeoffs in interpolation filter design are indentified and hearing-aid specifications are derived. The possibilities for hardware reduction...... in the interpolation filter are investigated. Proposed design simplifications presented here result in the least hardware demanding combination of oversampling ratio, number of stages and number of filter taps among a number of filters reported for audio applications....
Construction of a BNCT facility using an 8-MeV high power proton linac in Ibaraki
International Nuclear Information System (INIS)
An accelerator-based BNCT (Boron Neutron Capture Therapy) facility is now under construction and the entire system including the patient treatment system will be installed in the Ibaraki Neutron Advanced Medical Research Center (tentative name). BNCT is expected to give good results for inoperable cancers. In BNCT, pharmaceuticals carry a neutron capture agent containing 10B (Boron 10) selectively into tumor cells. Next thermal or epi-thermal neutrons interact with the 10B and produce α and 7Li-particles. Both of these particles have a very high Linear Energy Transfer (LET) and therefore lose almost all of their energy within a distance comparable to the size of a tumor cell. So far, BNCT has been provided only by nuclear reactors. The promising results shown there by BNCT give the hope that it may become an indispensable treatment modality for many types of cancers. From solely the neutron intensity point of view, nuclear reactors are excellent neutron sources. But as nuclear reactors regularly require long maintenance shut-downs and are subject to strict regulations, hospital operation is completely impractical. Thus we recognize the desirability of an accelerator-based BNCT facility well adapted for use by hospitals. We are aiming at the design and construction of a 'Hospital and Patient friendly' BNCT system. The development of such a BNCT requires multi-disciplinary input and collaboration from a wide spectrum of scientific and technical specialties. To obtain the needed breath and strength, we have organized our team with contributing specialists from diverse institutes and companies. The Ibaraki Medical Center for Advanced Neutron Therapy will be on the IQBRC (Ibaraki Quantum Beam Research Center) campus, which is near the JAEA and KEK Tokai campuses. The building for the BNCT is now under renovation by the Ibaraki prefectural government. We are tentatively calling this project 'I-BNCT' because of the Ibaraki prefectural sponsorship. Investigation of an 8
Non-linear and signal energy optimal asymptotic filter design
Directory of Open Access Journals (Sweden)
Josef Hrusak
2003-10-01
Full Text Available The paper studies some connections between the main results of the well known Wiener-Kalman-Bucy stochastic approach to filtering problems based mainly on the linear stochastic estimation theory and emphasizing the optimality aspects of the achieved results and the classical deterministic frequency domain linear filters such as Chebyshev, Butterworth, Bessel, etc. A new non-stochastic but not necessarily deterministic (possibly non-linear alternative approach called asymptotic filtering based mainly on the concepts of signal power, signal energy and a system equivalence relation plays an important role in the presentation. Filtering error invariance and convergence aspects are emphasized in the approach. It is shown that introducing the signal power as the quantitative measure of energy dissipation makes it possible to achieve reasonable results from the optimality point of view as well. The property of structural energy dissipativeness is one of the most important and fundamental features of resulting filters. Therefore, it is natural to call them asymptotic filters. The notion of the asymptotic filter is carried in the paper as a proper tool in order to unify stochastic and non-stochastic, linear and nonlinear approaches to signal filtering.
Directory of Open Access Journals (Sweden)
Sandeep Mukherjee
2012-11-01
Full Text Available Filters play an important role in most RF and Microwave applications. Currently, the electromagnetic spectrum is limited, and the applications are restricted to occupy just a portion of frequency range without affecting the equipment working out of band and also, without being affected by adjacent devices. Emerging applications such as wireless communications continue challenging RF/Microwave filters performance with even more stringent requirements, higher performance, smaller size, lighter weights, and low cost. Depending on the requirements and specifications, filters can mainly be designed with lumped or distributed elements. This paper describes the design of a newly proposed wide band micro strip band stop filter with open circuited stubs. This paper represents the design, simulation and fabrication of wideband bandstop filter using microstrip which is designed to have a center frequency of 2.5GHz. The filter is fabricated on a FR-4 substrate having dielectric constant
Design of FIR Filter Using Particle Swarm Optimization Algorithm for Audio Processing
Directory of Open Access Journals (Sweden)
Amanpreet Kaur
2012-08-01
Full Text Available In this paper, an optimal design of linear phase digital finiteimpulse response (FIR filter using Modified Particle SwarmOptimization (MPSO has been presented. In the designprocess, the filter length, pass band and stop band frequencies,pass band and stop band ripple sizes are specified. Sometimesthe gradient based optimization techniques are not effectivefor designing filter. An evolutionary method is introduced tofind the optimal solution of FIR filter design problem. MPSOis a global stochastic searching technique that can find out theglobal optima of the problem. A simulation results reveals theoptimization efficacy of the algorithm for the solution of,highly non-linear, and constrained filter design problems. Thedesigned filter is then applied on the audio application for upsampling of the audio signal. MATLAB toolkit functions areused for implementation of proposed algorithm.
All-Pole Recursive Digital Filters Design Based on Ultraspherical Polynomials
Directory of Open Access Journals (Sweden)
N. Stojanovic
2014-09-01
Full Text Available A simple method for approximation of all-pole recursive digital filters, directly in digital domain, is described. Transfer function of these filters, referred to as Ultraspherical filters, is controlled by order of the Ultraspherical polynomial, nu. Parameter nu, restricted to be a nonnegative real number (nu ≥ 0, controls ripple peaks in the passband of the magnitude response and enables a trade-off between the passband loss and the group delay response of the resulting filter. Chebyshev filters of the first and of the second kind, and also Legendre and Butterworth filters are shown to be special cases of these allpole recursive digital filters. Closed form equations for the computation of the filter coefficients are provided. The design technique is illustrated with examples.
Design of Reversible Multipliers for Linear Filtering Applications in DSP
Directory of Open Access Journals (Sweden)
Rakshith Saligram
2012-12-01
Full Text Available Multipliers in DSP computations are crucial. Thus modern DSP systems need to develop low power multipliers to reduce the power dissipation. One of the efficient ways to reduce power dissipation is by the use of bypassing technique. If a bit in the multiplier and/or multiplicand is zero the whole array of rowand/or diagonal will be bypassed and hence the name bypass multipliers. This paper presents the column Bypass multiplier and 2-D bypass multiplier using reversible logic; Reversible logic is a more prominent technology, having its applications in Low Power CMOS and quantum computations. The switching activity of any component in the bypass multiplier depends only on the input bit coefficients. The semultipliers find application in linear filtering FFT computational units, particularly during zero padding where there will be umpteen numbers of zeros. A bypass multiplier reduces the number of switching activities as well as the power consumption, above which reversible logic design acts to further almost nullify the dissipations
International Nuclear Information System (INIS)
We present design optimization of wavelength filters based on long period waveguide gratings (LPWGs) using the adaptive particle swarm optimization (APSO) technique. We demonstrate optimization of the LPWG parameters for single-band, wide-band and dual-band rejection filters for testing the convergence of APSO algorithms. After convergence tests on the algorithms, the optimization technique has been implemented to design more complicated application specific filters such as erbium doped fiber amplifier (EDFA) amplified spontaneous emission (ASE) flattening, erbium doped waveguide amplifier (EDWA) gain flattening and pre-defined broadband rejection filters. The technique is useful for designing and optimizing the parameters of LPWGs to achieve complicated application specific spectra. (paper)
Sakurai, Yoshinori; Tanaka, Hiroki; Takata, Takushi; Fujimoto, Nozomi; Suzuki, Minoru; Masunaga, Shinichiro; Kinashi, Yuko; Kondo, Natsuko; Narabayashi, Masaru; Nakagawa, Yosuke; Watanabe, Tsubasa; Ono, Koji; Maruhashi, Akira
2015-07-01
At the Kyoto University Research Reactor Institute (KURRI), a clinical study of boron neutron capture therapy (BNCT) using a neutron irradiation facility installed at the research nuclear reactor has been regularly performed since February 1990. As of November 2014, 510 clinical irradiations were carried out using the reactor-based system. The world's first accelerator-based neutron irradiation system for BNCT clinical irradiation was completed at this institute in early 2009, and the clinical trial using this system was started in 2012. A shift of BCNT from special particle therapy to a general one is now in progress. To promote and support this shift, improvements to the irradiation system, as well as its preparation, and improvements in the physical engineering and the medical physics processes, such as dosimetry systems and quality assurance programs, must be considered. The recent advances in BNCT at KURRI are reported here with a focus on physical engineering and medical physics topics.
Generalized Design Method for Voltage-Controlled Current-Mode Multifunction Filters
Directory of Open Access Journals (Sweden)
I. Lattenberg
2009-11-01
Full Text Available In the article, the Generalized Current Follower Transconductance Amplifier (GCFTA element for generalized frequency filter design and a novel active element, the Programmable Current Amplifier (PCA for the realization of the current-mode analog blocks, are presented. The paper also presents a method of general frequency filter design, whereas the basic circuit is a general autonomous circuit using GCFTA, PCA elements and general admittances. The properties of the proposed filter have been verified using PSPICE simulations.
Min-Max Design of FIR Digital Filters by Semidefinite Programming
Nagahara, Masaaki
2011-01-01
In this article we consider two problems: FIR (Finite Impulse Response) approximation of IIR (Infinite Impulse Response) filters and inverse FIR filtering of FIR or IIR filters. By means of Kalman-Yakubovich-Popov (KYP) lemma and its generalization (GKYP), the problems are reduced to semidefinite programming described in linear matrix inequalities (LMIs). MATLAB codes for these design methods are given. An design example shows the effectiveness of these methods.
BNCT Technology Development on HANARO Reactor
International Nuclear Information System (INIS)
So as to establish the biological effects of BNCT in the HANARO Reactor, biological damages in cells and animals with treatment of boron/neutron were investigated. And 124I-BPA animal PET image, analysis technology of the boron contents in the mouse tissues by ICP-AES was established. A Standard clinical protocol, a toxicity evaluation report and an efficacy investigation report of BNCT has been developed. Based on these data, the primary permission of clinical application was acquired through IRB of our hospital. Three cases of pre-clinical experiment for boron distribution and two cases of medium-sized animal simulation experiment using cat with verifying for 2 months after BNCT was performed and so the clinical demonstration with a patient was prepared. Also neutron flux, fast neutron flux and gamma ray dose of BNCT facility were calculated and these data will be utilized good informations for clinical trials and further BNCT research. For the new synthesis of a boron compound, o-carboranyl ethylamine, o-carboranylenepiperidine, o-carboranyl-THIQ and o-carboranyl-s-triazine derivatives were synthesized. Among them, boron uptake in the cancer cell of the triazine derivative was about 25 times than that of BPA and so these three synthesized methods of new boron compounds were patented
BNCT Technology Development on HANARO Reactor
Energy Technology Data Exchange (ETDEWEB)
Chun, Ki Jung; Park, Kyung Bae; Whang, Seung Ryul; Kim, Myong Seop
2007-06-15
So as to establish the biological effects of BNCT in the HANARO Reactor, biological damages in cells and animals with treatment of boron/neutron were investigated. And 124I-BPA animal PET image, analysis technology of the boron contents in the mouse tissues by ICP-AES was established. A Standard clinical protocol, a toxicity evaluation report and an efficacy investigation report of BNCT has been developed. Based on these data, the primary permission of clinical application was acquired through IRB of our hospital. Three cases of pre-clinical experiment for boron distribution and two cases of medium-sized animal simulation experiment using cat with verifying for 2 months after BNCT was performed and so the clinical demonstration with a patient was prepared. Also neutron flux, fast neutron flux and gamma ray dose of BNCT facility were calculated and these data will be utilized good informations for clinical trials and further BNCT research. For the new synthesis of a boron compound, o-carboranyl ethylamine, o-carboranylenepiperidine, o-carboranyl-THIQ and o-carboranyl-s-triazine derivatives were synthesized. Among them, boron uptake in the cancer cell of the triazine derivative was about 25 times than that of BPA and so these three synthesized methods of new boron compounds were patented.
Spectrum shaping of accelerator-based neutron beams for BNCT
Montagnini, B; Esposito, J; Giusti, V; Mattioda, F; Varone, R
2002-01-01
We describe Monte Carlo simulations of three facilities for the production of epithermal neutrons for Boron Neutron Capture Therapy (BNCT) and examine general aspects and problems of designing the spectrum-shaping assemblies to be used with these neutron sources. The first facility is based on an accelerator-driven low-power subcritical reactor, operating as a neutron amplifier. The other two facilities have no amplifier and rely entirely on their primary sources, a D-T fusion reaction device and a conventional 2.5 MeV proton accelerator with a Li target, respectively.
Radio Frequency Seeker Modelling and Seeker Filter Design
Directory of Open Access Journals (Sweden)
Prashant Vora
2005-07-01
Full Text Available Radio frequency seeker model, including receiver angle error noise modelling and filtering of noise from seeker measurement, is presented in this paper. The effects of eclipsing, radar cross section fluctuation, etc on seeker sight-line rate measurement are highlighted. The formulation for colour noise modelling of sight-line rate noise is derived based on the knowledge of seeker receiver angle error noise model. Two Kalman filter configurations for filtering of noise from seeker output have been considered in this paper, based on sight-line rate kinematics and noise characteristic. It has been observed from the simulation studies that sight-line rate signal varies slowly at higher interceptor-target ranges; with severe colour noise in sight line rate measurement, and therefore higher weightage for noise attenuation is beneficial in Kalman filter configuration. So, kinematic plus state augmentation for colour noise are considered for adequate filtering for higher interceptor-target ranges. Whereas for lower interceptor-target ranges, sight-line rate changes appreciably, which have been tracked by a simplified/modified spherical coordinate model, which uses knowledge of interceptor-target engagement dynamics. For both the filters, benefits of colour noise modelling and process model augmentation through coloured noise states, for filtering severe colour noise of seeker, has been demonstrated.
Designing Microstrip Low Pass Filter In ISM Band For Rectenna System
Directory of Open Access Journals (Sweden)
Pavan Sharma
2012-08-01
Full Text Available The filter is required in all RF-communication techniques. Low Pass Filters play an important role in wireless power transmission systems. Transmitted and received signals have to be filtered at a certain frequency with a specific bandwidth. In this paper the design of filter is done in the ISM (Industrial, Scientific and Medical band whose frequency lies between 1.55GHz- 3.99GHz. After getting the specifications required, we realized the filter structure with the help of CST-MW software.
Line filter design of parallel interleaved VSCs for high power wind energy conversion systems
DEFF Research Database (Denmark)
Gohil, Ghanshyamsinh Vijaysinh; Bede, Lorand; Teodorescu, Remus; Kerekes, Tamas; Blaabjerg, Frede
2015-01-01
for the two parallel interleaved VSCs is derived in order to obtain the worst case voltage magnitude of the individual harmonic components. The required value of the filter admittance for the specific harmonic component is obtained by using the worst case voltage magnitude and the allowable harmonic...... injection limit. In order to achieve the desired filter performance with optimal values of the filter parameters, the use of a LC trap branch with the conventional LCL filter is proposed. The expressions for the resonant frequencies of the proposed line filter are derived and used in the design to...
Software Engineering-Based Design for a Bayesian Spam Filter
Mumtaz Mohammed Ali AL-Mukhtar
2010-01-01
The rapid spread and the easy availability of a free e-mail service have made it the medium of choice for the sending of unsolicited advertising and bulk e-mail in general. These messages, known as junk e-mail or spam mail, are an increasing problem to both Internet users and Internet service providers (ISPs). The research resolves one aspect of the spam problem by developing an appropriate filter for the e-mail client. The proposed filter is a combination of three forms of filters: Whitelist...
Design of Microstrip Band Pass Fractal Filter for Suppression of Spurious Band
Directory of Open Access Journals (Sweden)
P. K. Singhal
2008-12-01
Full Text Available In this paper, the design and subsequent fabrication of a hairpin-line band pass filter has been proposed. This filter exhibits periodic frequency response. By proper design, the spurious bands are being suppressed significantly through the implementation of Koch fractal on the microstrip coupled line.
New optimal design method for trap damping sections in grid-connected LCL filters
DEFF Research Database (Denmark)
Beres, Remus Narcis; Wang, Xiongfei; Blaabjerg, Frede;
2014-01-01
A straightforward method is proposed in this paper to optimally design the damping sections of the LCL or LCL plus trap filters. The proposed method simplifies the iterative design procedure of the overall filter while ensuring minimum resonance peaking and smaller capacitor than otherwise would ...
The time-of-flight epithermal neutron spectrum measurement from accelerator based BNCT facility
International Nuclear Information System (INIS)
Results of epithermal neutrons spectrum measurement by time-of-flight method for different beam shaping assembly designed for BNCT purposes are presented. Discuss method to realize time-of-flight measurement at accelerator. Results looks are important for beam shaping assembly optimization and accurate and reliable treatment planning. (author)
Design and Simulation of Edge-Coupled Stripline Band Pass Filter for U band
Directory of Open Access Journals (Sweden)
Pawan Shakdwipee
2013-08-01
Full Text Available In this paper, a band pass filter structure using Ansoft designer software and Matlab software simulation tool are presented. The filter is operated at U Band range in higher order 50 GHz edge-coupled Stripline band pass filter for different microwave application. For the proposed work we consider simulation using Roger R03203 substrate with dielectric constant of 3.02, Conductor Thickness 0.035 mm and Substrate Height 0.787 mm. This filter is design at a center frequency of 50 GHz with 8 GHz bandwidth. Simulation results show that the filter operation is optimum and best in this range and results show good performance and agree well with the high frequency EM full wave simulation. In this paper, band pass filter development with the assistance of the Richards-Kuroda Transformation method, is used. Moreover, measured S parameters denote the center frequency is also strongly influenced by the variation of Roger's material's dielectric constants. By analyzing the characteristics at center frequency of the filter, both theoretical and simulated data are accumulated for broadening application filed. The band pass filter exhibits advantages of small size and high reliability compared to conventional planar filter structure, which makes the band pass filter suitable for U Band communicational application. This filter shows attractive characteristics for BPF applications.
A Top-Down Optimization Methodology for SC Filter Circuit Design Using Varying Goal Specifications
Serra, Hugo; Santos-Tavares, Rui; Paulino, Nuno
2014-01-01
Part 19: Electronics: Design International audience The design of Switched-Capacitor (SC) filters can be an arduous process, which becomes even more complex when the high gain amplifier is replaced by a low gain amplifier or a voltage follower. This eliminates the virtual ground node, requiring the compensation of the parasitic capacitances during the design phase. This paper proposes an automatic procedure for the design of SC filters using low gain amplifiers, based on a Genetic Algor...
The design of digital all-pass filters using second-order cone programming (SOCP)
Chan, SC; Chen, HH; Pun, CKS
2005-01-01
This brief proposes a new method for designing digital all-pass filters with a minimax design criterion using second-order cone programming (SOCP). Unlike other all-pass filter design methods, additional linear constraints can be readily incorporated. The overall design problem can be solved through a series of linear programming subproblems and the bisection search algorithm. The convergence of the algorithm is guaranteed. Nonlinear constraints such as the pole radius constraint of the filte...
Design of Super-resolution Filters with a Gaussian Beam in Optical Data Storage Systems
International Nuclear Information System (INIS)
Super-resolution filters based on a Gaussian beam are proposed to reduce the focusing spot in optical data storage systems. Both of amplitude filters and pure-phase filters are designed respectively to gain the desired intensity distributions. Their performances are analysed and compared with those based on plane wave in detail. The energy utilizations are presented. The simulation results show that our designed super-resolution filters are favourable for use in optical data storage systems in terms of performance and energy utilization
Design and Simulation of Edge-Coupled Stripline Band Pass Filter for U band
Pawan Shakdwipee
2013-01-01
In this paper, a band pass filter structure using Ansoft designer software and Matlab software simulation tool are presented. The filter is operated at U Band range in higher order 50 GHz edge-coupled Stripline band pass filter for different microwave application. For the proposed work we consider simulation using Roger R03203 substrate with dielectric constant of 3.02, Conductor Thickness 0.035 mm and Substrate Height 0.787 mm. This filter is design at a center frequency of 50 GHz with 8 GHz...
A Robust Filter Design for Uncertain Singular Systems with Unreliable Channels
Directory of Open Access Journals (Sweden)
Ching-Min Lee
2011-06-01
Full Text Available This paper considers the problem of robust H_∞ filter design in uncertain discrete-time singular systems with possible missing measurements due to unreliable network transmission channels. The stochastic variable satisfying Bernoulli random binary distribution is introduced to model the missing phenomena and the corresponding filtering error dynamics with delay is then induced. We provide a set of sufficient conditions for the existence of the desired filter, and propose a robust filter design method under a strict linear matrix inequality framework. A numerical example is given to illustrate the effectiveness of the proposed method
Effect of the Design Parameters on the Performance of Inner Recycling Continuous Sand Filter
Institute of Scientific and Technical Information of China (English)
CHEN Zhi-qiang; WEN Qin-xue; Lü Bing-nan
2002-01-01
A novel integrated water treatment facility, innerrecycling continuous sand filter, is discussed. The theory of micro-flocculation is applied in the sand-washing circulation system with continuous filtration and backwashing. The design and operation parameters,which affect the performance of the filter, are discussed.The key design parameters are provided as follows:diameter of filter material is 0.7 to 1.0 mm, depth of filter bed is 0.6 m, filtration velocity is less than 12 m/h,ratio of gas to water is 9:11 and sand recycling rate is 2 to 4 mm/min.
BNCT for malignant brain tumors in children
International Nuclear Information System (INIS)
BSH-based intra-operative BNCT as an initial treatment underwent in 4 children with malignant brain tumors since 1998. There were 2 glioblastomas, one primitive neuroectodermal tumor (PNET) and one anaplastic ependymoma patient. They included two children under 3-year-old. All GBM patients were died of CSF dissemination without tumor regrowth in the primary site. Another PNET and anaplastic ependymoma patients are still alive without tumor recurrence. We can consider BNCT is optimal treatment modality for malignant brain tumor in children. (author)
Production of epithermal neutron beams for BNCT
Bisceglie, E; Colonna, N; Paticchio, V; Santorelli, P; Variale, V
2002-01-01
The use of boron neutron capture therapy (BNCT) for the treatment of deep-seated tumors requires neutron beams of suitable energy and intensity. Simulations indicate the optimal energy to reside in the epithermal region, in particular between 1 and 10 keV. Therapeutic neutron beams with high spectral purity in this energy range could be produced with accelerator-based neutron sources through a suitable neutron-producing reaction. Herein, we report on different solutions that have been investigated as possible sources of epithermal neutron beams for BNCT. The potential use of such sources for a hospital-based therapeutic facility is discussed.
Effect of shaped filter design on dose and image quality in breast CT
International Nuclear Information System (INIS)
The purpose of this study was to investigate the effect of shaped filters specifically designed for dedicated breast computed tomography (CT) scanners on dose and image quality. Optimization of filter shape and material in fan direction was performed using two different design methods, one aiming at homogeneous noise distributions in the CT images and the other aiming at a uniform dose distribution in the breast. The optimal filter thickness as a function of fan angle was determined iteratively to fulfil the above mentioned criteria for each breast diameter. Different filter materials (aluminium, copper, carbon, polytetrafluoroethylene) and breast phantoms with diameters between 80–180 mm were investigated. Noise uniformity in the reconstructed images, obtained from CT simulations based on ray-tracing methods, and dose in the breast, calculated with a Monte Carlo software tool, were used as figure of merit. Furthermore, CT-value homogeneity, the distribution of noise in cone direction, spatial resolution from centre to periphery and the contrast-to-noise ratio weighted by dose (CNRD) were evaluated. In addition, the decrease of scatter due to shaped filters was investigated. Since only few or one filter are practical in clinical CT systems, the effects of one shaped filter for different breast diameters were also investigated. In this case the filter, designed for the largest breast diameter, was simulated at variable source-to-filter distances depending on breast diameter. With the filter design method aiming at uniform noise distribution best results were obtained for aluminium as the filter material. Noise uniformity improved from 20% down to 5% and dose was reduced by about 30–40% for all breast diameters. No decrease of noise uniformity in cone direction, CT-value homogeneity, spatial resolution and the CNRD was detected with the shaped filter. However, a small improvement of CNRD was observed. Furthermore, a scatter reduction of about 20–30% and a more
On the Polyphase Decomposition for Design of Generalized Comb Decimation Filters
Laddomada, Massimiliano
2007-01-01
Generalized comb filters (GCFs) are efficient anti-aliasing decimation filters with improved selectivity and quantization noise (QN) rejection performance around the so called folding bands with respect to classical comb filters. In this paper, we address the design of GCF filters by proposing an efficient partial polyphase architecture with the aim to reduce the data rate as much as possible after the Sigma-Delta A/D conversion. We propose a mathematical framework in order to completely characterize the dependence of the frequency response of GCFs on the quantization of the multipliers embedded in the proposed filter architecture. This analysis paves the way to the design of multiplier-less decimation architectures. We also derive the impulse response of a sample 3rd order GCF filter used as a reference scheme throughout the paper.
Resilient Minimum Entropy Filter Design for Non-Gaussian Stochastic Systems
Lei Guo; Hong Wang; Yan Wang
2013-01-01
In this paper, the resilient minimum entropy filter problem is investigated for the stochastic systems with non-Gaussian disturbances. The goal of designing the filter is to guarantee that the entropy of the estimation error is monotonically decreasing, moreover, the error system is exponentially ultimately bounded in the mean square. Based on the entropy performance function, a filter gain updating algorithm is presented to make the entropy decrease at every sampling instant k. Then the boun...
Designing a Microwave Filter by Studying and Simulating the Discontinuity in the Waveguide
Ghafir Ibrahim; Přenosil Václav
2013-01-01
This research aims to design a microwave filter by studying and simulating the discontinuity in the waveguide. We suggest a filter consists of three waveguides connected to each other and different dimensions. Changing the dimensions of the waveguide will change the conditions of propagation of microwaves and in our suggested filter we have two discontinuity regions affecting on the modes of frequencies propagated through the waveguide. We apply Galerkin method for studying the discontinuity ...
Design and Efficiency Analysis of one Class of Uniform Linear Phase FIR Filter Banks
Directory of Open Access Journals (Sweden)
R. D. Pantić
2013-11-01
Full Text Available One class of uniform linear phase filter banks with different numbers of band-pass channels will be considered in this study, concentrating on 5, 9 and 17-band filter banks and their mutual comparison concerning delay and implementation complexity. Designed banks are based on the FIR filters and frequency response masking technique and are also compared to the banks with direct realization considering complementarity and delay.
Performance and environmental characteristics of a compact, high-capacity HEPA filter design
International Nuclear Information System (INIS)
An improved version of the HEPA filter has been developed and evaluated for conformity with MIL-51068. In this design, the filter paper (conforming to MIL-F-51079) is pleated to a depth of only 18 mm. Ribbons essentially the same material as the filter paper form inter-pleat spacers, providing a crest-to-crest spacing of 3 mm. The resultant filter has the same DOP penetration level as the standard MIL-F-51068 HEPA filter, but about half its pressure drop at the same airflow. Materials of construction, adhesives, gaskets and faceguards match MIL-f-51068. Both flat-panel and zig-zag configurations of the filter meet the rough handling test of MIL-F-51068. Preliminary indications are that both filters will meet the overpressure tests of MIL-F-51068D and the flammability requirements of UL 586; these tests are in progress. Filters can be supplied to interchange with existing HEPA filter sizes. The improved pressure drop characteristic of these filters can be used to provide longer intervals between filter changes, or equal life at greater capacity
Neutron and photon fields in the BNCT room with closed beam shutters
International Nuclear Information System (INIS)
The epithermal neutron beam at the LVR-15 reactor was designed for the Boron Neutron Capture Therapy (BNCT) of cancers, but it has also been used for material testing. In the case where the beam is closed with two designed shutters, there is still an indispensable background in the irradiation room, which limits the movement of persons during patient positioning before exposure or during the preparation of the samples. Because the epithermal filter of the beam was designed in a former thermal column, as a multi-layer system, it was suspected that both fast neutrons and photons penetrated the filter shielding into the room. The purpose of this study was to determine the causes of potential faulty shielding and to estimate the doses to persons who perform the irradiation experiments and/or exposure of patients. The quality of the shielding was evaluated from two-dimensional measurements of both neutron and photon distribution on the surface of the beam shutter. During the measurement both the shutters of the epithermal beam were closed and the reactor was operated at the nominal power of 9 MW. This experimental arrangement is similar to the conditions that exist when either the irradiation experiments or the exposure of patients is performed in this room. The neutron space distribution was measured using a Bonner sphere of φ 76.2 mm diameter with an LiI(Tl) scintillation detector of φ 4 x 8 mm. A small Geiger-Muller tube was used for the measurement of photon distribution. The detectors were placed on a three-dimensional positioning equipment controlled by a computer, which enabled automatic measurement with 1 cm mesh step. Results of the measurement show that the background profile in the irradiation room has reasonable maximum only at the beam aperture. Published by Univ. of Press. All rights reserved. (authors)
Characteristics of the new THOR epithermal neutron beam for BNCT
International Nuclear Information System (INIS)
A characterization of the new Tsing Hua open-pool reactor (THOR) epithermal neutron beam designed for boron neutron capture therapy (BNCT) has been performed. The facility is currently under construction and expected in completion in March 2004. The designed epithermal neutron flux for 1 MW power is 1.7x109 n cm-2 s-1 in air at the beam exit, accompanied by photon and fast neutron absorbed dose rates of 0.21 and 0.47 mGy s-1, respectively. With 10B concentrations in normal tissue and tumor of 11.4 and 40 ppm, the calculated advantage depth dose rate to the modified Snyder head phantom is 0.53 RBE-Gy min-1 at the advantage depth of 85 mm, giving an advantage ratio of 4.8. The dose patterns determined by the NCTPlan treatment planning system using the new THOR beam for a patient treated in the Harvard-MIT clinical trial were compared with results of the MITR-II M67 beam. The present study confirms the suitability of the new THOR beam for possible BNCT clinical trials
Hintzen, E.; Vennemann, T.; Mathis, W.
2014-11-01
In this paper a new filter design concept is proposed and implemented which takes into account the complex loudspeaker impedance. By means of techniques of broadband matching, that has been successfully applied in radio technology, we are able to optimize the reconstruction filter to achieve an overall linear frequency response. Here, a passive filter network is inserted between source and load that matches the complex load impedance to the complex source impedance within a desired frequency range. The design and calculation of the filter is usually done using numerical approximation methods which are known as Real Frequency Techniques (RFT). A first approach to systematic design of reconstruction filters for class-D amplifiers is proposed, using the Simplified Real Frequency Technique (SRFT). Some fundamental considerations are introduced as well as the benefits and challenges of impedance matching between class-D amplifiers and loudspeakers. Current simulation data using MATLAB is presented and supports some first conclusions.
Design of generalised orthogonal filters: application to the modelling of dynamical systems
Nikolić, Saša S.; Antić, Dragan S.; Perić, Staniša Lj.; Danković, Nikola B.; Milojković, Marko T.
2016-02-01
In this article, we define a new class of orthogonal filters with complex poles and zeroes inside their transfer function. This further improvement of classical orthogonal filters allows the possibility to model a wider range of real systems, that is, the systems whose mathematical models have complex zeroes besides real ones. These filters can be applied in the following areas: circuit theory, telecommunications, signal processing, bond graphs, theory approximations and control system theory. First, we describe the rational functions with complex poles and zeroes, and prove their orthogonality. Based on these functions, we designed the block diagram of orthogonal Legendre-type filter with complex poles and zeroes. After that an appropriate analogue scheme of this filter for practical realisation is derived. To validate theoretical results, we performed an experiment with a cascade-connected system designed and practically realised in our laboratories. The experiments proved the quality of the designed orthogonal model in terms of accuracy and simplicity.
Clinical results of boron neutron capture therapy (BNCT) for glioblastoma
International Nuclear Information System (INIS)
The purpose of this study was to evaluate the clinical outcome of BSH-based intra-operative BNCT (IO-BNCT) and BSH and BPA-based non-operative BNCT (NO-BNCT). We have treated 23 glioblastoma patients with BNCT without any additional chemotherapy since 1998. The median survival time (MST) of BNCT was 19.5 months, and 2-year, 3-year and 5-year survival rates were 26.1%, 17.4% and 5.8%, respectively. This clinical result of BNCT in patients with GBM is superior to that of single treatment of conventional radiotherapy compared with historical data of conventional treatment. - Highlights: ► In this study, we evaluate the clinical outcome of boron neutron capture therapy (BNCT) for malignant brain tumors. ► We have treated 23 glioblastoma (GBM) patients with BNCT without any additional chemotherapy. ► Clinical results of BNCT in patients with GBM are superior to that of single treatment of conventional radiotherapy compared with historical data of conventional treatment.
Computer aided design of reentrant coaxial filters including coaxial excitation
Boria, V.; Gerini, G.; Guglielmi, M.
1999-01-01
An advanced EM based CAD tool is used for the detailed characterisation of a family of reentrant coaxial waveguide filters. The EM analysis includes the effects of tuning screws and of the input/output coaxial excitation. The software is essentially used as an efficient replacement for the tradition
INEL BNCT Program: Volume 5, No. 9
Energy Technology Data Exchange (ETDEWEB)
Ackermann, A.L. (ed.)
1991-01-01
This Bulletin presents a summary of accomplishments and highlights of the Idaho National Engineering Laboratory's (INEL) Boron Neutron Capture Therapy (BNCT) Program for September 1991. This bulletin includes information on the brain tumor and melanoma research programs, Power Burst Facility (PBF) technical support and modifications, PBF operations, and updates to the animal data charts.
Introducing BNCT treatment in new treatment facilities
International Nuclear Information System (INIS)
The physical and radiobiological studies that should be performed before the initiation of BNCT are discussed. The need for dose-escalation versus response studies in large animal models is questioned. These studies are time consuming, expensive and legally difficult in some countries and may be dispensable. (author)
Optimal design and performance verification of a broadband waveguide filter using ANN-GA algorithm
Directory of Open Access Journals (Sweden)
Manidipa Nath
2013-09-01
Full Text Available In this work design and optimization of EBGstructure having multiple dielectric posts uniformly placed insidea rectangular waveguide is done to extract filter responses.Frequency response of BPF configuration using trained ANNmodel of multipost rectangular waveguide are studied andoptimized using GA. The geometrical and positional dimensionof post parameters are varied in accordance to the requirementof reflectance and transmittance of the filter.
Optimal design and performance verification of a broadband waveguide filter using ANN-GA algorithm
Manidipa Nath; Sudhabindu Ray; Bhaskar Gupta
2013-01-01
In this work design and optimization of EBGstructure having multiple dielectric posts uniformly placed insidea rectangular waveguide is done to extract filter responses.Frequency response of BPF configuration using trained ANNmodel of multipost rectangular waveguide are studied andoptimized using GA. The geometrical and positional dimensionof post parameters are varied in accordance to the requirementof reflectance and transmittance of the filter.
Design of efficient circularly symmetric two-dimensional variable digital FIR filters.
Bindima, Thayyil; Elias, Elizabeth
2016-05-01
Circularly symmetric two-dimensional (2D) finite impulse response (FIR) filters find extensive use in image and medical applications, especially for isotropic filtering. Moreover, the design and implementation of 2D digital filters with variable fractional delay and variable magnitude responses without redesigning the filter has become a crucial topic of interest due to its significance in low-cost applications. Recently the design using fixed word length coefficients has gained importance due to the replacement of multipliers by shifters and adders, which reduces the hardware complexity. Among the various approaches to 2D design, transforming a one-dimensional (1D) filter to 2D by transformation, is reported to be an efficient technique. In this paper, 1D variable digital filters (VDFs) with tunable cut-off frequencies are designed using Farrow structure based interpolation approach, and the sub-filter coefficients in the Farrow structure are made multiplier-less using canonic signed digit (CSD) representation. The resulting performance degradation in the filters is overcome by using artificial bee colony (ABC) optimization. Finally, the optimized 1D VDFs are mapped to 2D using generalized McClellan transformation resulting in low complexity, circularly symmetric 2D VDFs with real-time tunability. PMID:27222739
Equalization of Loudspeaker and Room Responses Using Kautz Filters: Direct Least Squares Design
Directory of Open Access Journals (Sweden)
Tuomas Paatero
2007-01-01
Full Text Available DSP-based correction of loudspeaker and room responses is becoming an important part of improving sound reproduction. Such response equalization (EQ is based on using a digital filter in cascade with the reproduction channel to counteract the response errors introduced by loudspeakers and room acoustics. Several FIR and IIR filter design techniques have been proposed for equalization purposes. In this paper we investigate Kautz filters, an interesting class of IIR filters, from the point of view of direct least squares EQ design. Kautz filters can be seen as generalizations of FIR filters and their frequency-warped counterparts. They provide a flexible means to obtain desired frequency resolution behavior, which allows low filter orders even for complex corrections. Kautz filters have also the desirable property to avoid inverting dips in transfer function to sharp and long-ringing resonances in the equalizer. Furthermore, the direct least squares design is applicable to nonminimum-phase EQ design and allows using a desired target response. The proposed method is demonstrated by case examples with measured and synthetic loudspeaker and room responses.
Computer-aided design of nano-filter construction using DNA self-assembly
Mohammadzadegan Reza; Mohabatkar Hassan
2006-01-01
AbstractComputer-aided design plays a fundamental role in both top-down and bottom-up nano-system fabrication. This paper presents a bottom-up nano-filter patterning process based on DNA self-assembly. In this study we designed a new method to construct fully designed nano-filters with the pores between 5 nm and 9 nm in diameter. Our calculations illustrated that by constructing such a nano-filter we would be able to separate many molecules.
Design and analysis of planar printed microwave and PBG filters using an FDTD method
DEFF Research Database (Denmark)
Tong, M.S.; Lu, Y.L.; Chen, Y.C.;
2004-01-01
In this paper, various planar printed microwave and photonic band-gap (PBG) filters have been designed and analyzed by applying the finite difference time domain method, together with an unsplit-anisotropic perfectly matched layer technique as treatments of boundary conditions. The implemented...... solver was first validated by comparing the computed data with those published in literature, and a good agreement was observed between the results. Then, based on the specified design criteria, various microwave and PBG filters were designed and analyzed, in which the theoretical predictions matched...... well with the computed results for the characteristics of the proposed filters....
Filter designs based on coupled transmission line model for double split ring resonators
DEFF Research Database (Denmark)
Yan, Lei; Tang, Meng; Krozer, Viktor;
2012-01-01
This work presents a systematic way to design filters based on coupled transmission line model of the microstrip rectangular double split ring resonators (DSRRs). This model allows to estimate all resonance modes of DSRR and extract the quality factors of the structure for filter synthesis purpose....... According to the filter specifications, the low‐pass prototype parameters are used to calculate the required coupling coefficients between coupled DSRRs. The corresponding coupling coefficients are realized by using asymmetric coupled multi‐conductors networks. The proposed filter synthesis approach...
Gabor Filter Design for Fingerprint Application Using Matlab and Verilog HDL
Directory of Open Access Journals (Sweden)
R.Dhanabal
2013-04-01
Full Text Available This paper demonstrates the application of Gabor Filter technique to enhance the fingerprint image. This work produces change in Gabor filter design by increasing the quality of an output which helps in higher security applications. The incoming signal in form of image pixel will be convoluted by Gabor filter to define the Edge and vale regions of fingerprint. The main characteristic of this paper is tostore image pixel in memory if convolution signal is low and if the signal is high image is filtered.
Modeling and design of surface acoustic wave filters and their military applications
Directory of Open Access Journals (Sweden)
Marija F. Hribšek
2011-07-01
Full Text Available The operation principles of surface acoustic wave filters (SAW and materials and technology of their fabrication are presented. A special attention is paid to wide and diverse applications of SAW filters in signal processing, communications and chemical sensors, stressing their military applications. An original method, developed by the authors, for the modeling and prediction of SAW filter characteristics is presented. The abilities of the method are illustrated by the examples of chemical SAW sensors for the detection of warfare chemical agents. The designed and fabricated SAW filter PAT-FPO is the base for the special purpose chemical sensors.
Akudago Apambilla, John; Nishigaki, Makoto; Chegbeleh Larry, Pax; Alim, Md. Abdul; Komatsu, Mitsuru; Kumamaru, Koji
2008-01-01
Filters are essential in the design of embankments/dams, drains and wells for water and oil supplies. Asa result of these functions, filter use is increasing. In order to use the required filter, various empirical relationshave been given based on mathematical and field experience. However, these guidelines have notworked to perfection considering the fact that clogging within the filter face is a serious challenge. Ashort review on filter design criteria is given in this script coupled with ...
A novel optimized LCL-filter designing method for grid connected converter
DEFF Research Database (Denmark)
Guohong, Zeng; Rasmussen, Tonny Wederberg; Teodorescu, Remus
2010-01-01
This paper presents a new LCL-filters optimized designing method for grid connected voltage source converter. This method is based on the analysis of converter output voltage components and inherent relations among LCL-filter parameters. By introducing an optimizing index of equivalent total...... capacity of all filter components, with clear physical meaning of minimum cost and volume, a set of optimal values of attenuation ratio and inductancesplit- ratio is obtained for deciding all LCL-filter parameters. With this method, filter overall capacity can be minimized while the grid limit of switching...... frequency distortion is fulfilled. Compared to the existing methods, the proposed method contains only four steps without try-and-error process, so it is efficient and easy to implement. Simulation results of a 50kVA grid-connected inverter with two sets of LCL-filter parameters under different optimizing...
Design of Stable Circularly Symmetric Two-Dimensional GIC Digital Filters Using PLSI Polynomials
Directory of Open Access Journals (Sweden)
Eswaran C
2007-01-01
Full Text Available A method for designing stable circularly symmetric two-dimensional digital filters is presented. Two-dimensional discrete transfer functions of the rotated filters are obtained from stable one-dimensional analog-filter transfer functions by performing rotation and then applying the double bilinear transformation. The resulting filters which may be unstable due to the presence of nonessential singularities of the second kind are stabilized by using planar least-square inverse polynomials. The stabilized rotated filters are then realized by using the concept of generalized immittance converter. The proposed method is simple and straight forward and it yields stable digital filter structures possessing many salient features such as low noise, low sensitivity, regularity, and modularity which are attractive for VLSI implementation.
Optimal design of 2D digital filters based on neural networks
Wang, Xiao-hua; He, Yi-gang; Zheng, Zhe-zhao; Zhang, Xu-hong
2005-02-01
Two-dimensional (2-D) digital filters are widely useful in image processing and other 2-D digital signal processing fields,but designing 2-D filters is much more difficult than designing one-dimensional (1-D) ones.In this paper, a new design approach for designing linear-phase 2-D digital filters is described,which is based on a new neural networks algorithm (NNA).By using the symmetry of the given 2-D magnitude specification,a compact express for the magnitude response of a linear-phase 2-D finite impulse response (FIR) filter is derived.Consequently,the optimal problem of designing linear-phase 2-D FIR digital filters is turned to approximate the desired 2-D magnitude response by using the compact express.To solve the problem,a new NNA is presented based on minimizing the mean-squared error,and the convergence theorem is presented and proved to ensure the designed 2-D filter stable.Three design examples are also given to illustrate the effectiveness of the NNA-based design approach.
Progress In The Development Of A Tomographic SPECT System For Online Dosimetry In BNCT
International Nuclear Information System (INIS)
In boron neutron capture therapy (BNCT) the delivered dose to the patient depends both on the neutron beam characteristics and on the 10B body distribution which, in turn, is governed by the tumor specificity of the 10B drug-carrier. BNCT dosimetry is a complex matter due to the several interactions that neutrons can undergo with the different nuclei present in tissue. However the boron capture reaction 10B(n,α)7Li accounts for about 80 % of the total dose in a tumor with 40 ppm in 10B concentration. Present dosimetric methods are indirect, based on drug biodistribution statistical data and subjected to inter and intra-patient variability. In order to overcome the consequences of the concomitant high dosimetric uncertainties, we propose a SPECT (Single Photon Emission Tomography) approach based on the detection of the prompt gamma-ray (478 keV) emitted in 94 % of the cases from 7Li. For this purpose we designed, built and tested a prototype based on LaBr3(Ce) scintillators. Measurements on a head and tumor phantom were performed in the accelerator-based BNCT facility of the University of Birmingham (UK). They result in the first tomographic image of the 10B capture distribution obtained in a BNCT facility.
Design and development of laser eye protection filter
International Nuclear Information System (INIS)
Laser based devices, have been operational for measurement of distances horizontally and vertically in avionics and surveillance industries. These equipments are functional on pulsed Nd:YAG laser at 1064nm, this wavelength elevate the risk of eye exposure to personnel at unexpected levels. In this paper the eye protection filters, for the wavelength 1064nm were developed with soft (ZnS) and hard (TiO2) coating materials by using thin film vacuum coating technique. The damage threshold of the filter is 0.2 J/cm2. Transmission characteristics are measured and discussed. Optical damage threshold (for eye 5 × 10−6 J/cm2) at various distances is also simulated.
International Nuclear Information System (INIS)
Boron neutron capture therapy (BNCT) is an experimental technique for the treatment of certain kinds of tumors. Research in BNCT is performed utilizing both thermal and epithermal neutron beams. Epithermal neutrons (0.4 eV-10 keV) penetrate more deeply into tissue and are thus used in non-superficial clinical applications such as the brain glioma. In the last few years, the fast reactor TAPIRO (ENEA-Casaccia Rome) has been employed as a neutron source for research into BNCT applications. Recently, an 'epithermal therapeutic column' has been designed and its construction has been completed. The Monte Carlo code MCNPX was employed to optimize the design of the column and to evaluate the dose profiles and the therapeutic parameters in the cranium of the anthropomorphic phantom ADAM. In the same context, some preliminary evaluations of the undesirable doses to the patient were performed with MCNPX. A hermaphrodite phantom derived from ADAM and EVA was employed to evaluate the energy deposition in some organs during a standard BNCT treatment. The total dose consists of the contributions from the primary neutron beam, the neutron interactions with boron and the neutron induced photons generated in the epithermal column structures and in the patient's tissues. The paper summarizes the computational procedure and provides a general dosimetric framework of the patient radiological protection aspects related to a BNCT treatment scenario at the TAPIRO reactor. (authors)
Providing Eligibility Criteria On Turbocharger Filter Silencer Design Processes
Adem GÜLERYÜZ
2013-01-01
Supply of ventilation air to either the engine room or diesel engine directly affects engine performances. Main criteria is supply of air volume and pressure into the cylinder. When Air starts to come until the cylinders, there many points which behave as restrictions. These are ventilation grills. ventilation fans, ventilation casings, misteliminators, manual or pneumatically adjusted fan dampers, number of bending of ventilation casing, cleanness of casings, air flow speed, air filters, tur...
Polyphase Structure Based Eigen Design of Two-Channel Quadrature Mirror Filter Bank
Directory of Open Access Journals (Sweden)
S. K. Agrawal
2014-09-01
Full Text Available This paper presents a method for the design of two-channel quadrature mirror filter (QMF banks with linear phase in frequency domain. Low-pass prototype filter of the QMF bank is implemented using polyphase decomposition. Prototype filter coefficients are optimized to minimize an objective function using eigenvalue-eigenvector approach without matrix inversion. The objective function is formulated as a weighted sum of four terms, pass-band error and stop-band residual energy of low-pass analysis filter, the square error of the overall transfer function at the quadrature frequency and amplitude distortion of the filter bank. The simulation results clearly show that the proposed method requires less computational efforts in comparison to the other state-of-art existing design methods.
Big Bang–Big Crunch Optimization Algorithm for Linear Phase Fir Digital Filter Design
Directory of Open Access Journals (Sweden)
Ms. Rashmi Singh Dr. H. K. Verma
2012-02-01
Full Text Available The Big Bang–Big Crunch (BB–BC optimization algorithm is a new optimization method that relies on the Big Bang and Big Crunch theory, one of the theories of the evolution of the universe. In this paper, a Big Bang–Big Crunch algorithm has been used here for the design of linear phase finite impulse response (FIR filters. Here the experimented fitness function based on the mean squared error between the actual and the ideal filter response. This paper presents the plot of magnitude response of FIR filters and error graph. The BB-BC seems to be promising tool for FIR filter design especially in a dynamic environment where filter coefficients have to be adapted and fast convergence is of importance.
Singh, R.; Verma, H. K.
2013-12-01
This paper presents a teaching-learning-based optimization (TLBO) algorithm to solve parameter identification problems in the designing of digital infinite impulse response (IIR) filter. TLBO based filter modelling is applied to calculate the parameters of unknown plant in simulations. Unlike other heuristic search algorithms, TLBO algorithm is an algorithm-specific parameter-less algorithm. In this paper big bang-big crunch (BB-BC) optimization and PSO algorithms are also applied to filter design for comparison. Unknown filter parameters are considered as a vector to be optimized by these algorithms. MATLAB programming is used for implementation of proposed algorithms. Experimental results show that the TLBO is more accurate to estimate the filter parameters than the BB-BC optimization algorithm and has faster convergence rate when compared to PSO algorithm. TLBO is used where accuracy is more essential than the convergence speed.
H∞ deconvolution filter design for time-delay linear continuous-time systems
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
Proposes an H∞ deconvolution design for time-delay linear continuous-time systems. We first analyze the general structure and innovation structure of the H∞ deconvolution filter. The deconvolution filter with innovation structure is made up of an output observer and a linear mapping, where the latter reflects the internal connection between the unknown input signal and the output estimate error. Based on the bounded real lemma,a time domain design approach and a sufficient condition for the existence of deconvolution filter are presented.The parameterization of the deconvolution filter can be completed by solving a Riccati equation. The proposed method is useful for the case that does not require statistical information about disturbances. At last, a numerical example is given to demonstrate the performance of the proposed filter.
International Nuclear Information System (INIS)
The boron neutron capture therapy is based on the reaction occurring between the isotope 10B and thermal neutrons. A low energy neutron is captured by the nucleus and it disintegrates into two densely ionising particles, Li nucleus and He nucleus (α particle), with high biological effectiveness. On the basis of comprehensive preclinical investigations in the frame of the European Collaboration with Na2B12H11SH (BSH), as boron delivery agent, the first European phase I, clinical trial was designed at the only available epithermal beam in Europe, at the High Flux Reactor, Petten, in the Netherland. The goal of this study is to establish the safe BNCT dose for cranial tumors under defined conditions. BNCT is applied as postoperative radiotherapy in 4 fractions, after removal of the tumor for a group of patients suffering from glioblastoma, who would have no benefit from conventional treatment, but have sufficient life expectancy to detect late radiation morbidity due to BNCT. The starting dose is set at 80% of the dose where neurological effects occured in preclinical large animal experiments following a single fraction. The radiation dose will be escalated, by constant boron concentration in blood, in 4 steps for cohorts of ten patients, after an observation period of at least 6 months after the end of BNCT of the last patient of a cohort. The adverse events on healthy tissues due to BSH and due to the radiotherapy will be analysed in order to establish the maximal tolerated dose and dose limiting toxicity. Besides of the primary aim of this study the survival will be recorded. The first patient was treated in October 1997, and further four patients have been irradiated to date. The protocol design proved to be well applicable, establishing the basis for scientific evaluation, for performance of safe patient treatment in a very complex situation and for opening the possibility to perform further clinical research work on BNCT. (orig.)
Innovative HEPA filter designs to reduce waste generation and simplify waste treatment
International Nuclear Information System (INIS)
The treatment and disposal of spent high-efficiency particulate air (HEPA) filters has presented a problem at some defense production plants and could be a problem at potential future spent-fuel consolidation or fuel-reprocessing facilities. During studies of transuranic (TRU) waste treatment options conducted by Pacific Northwest Laboratory, it was concluded that treatment of spent HEPA filters would become easier and less costly if some modifications were made to the present materials of construction and design. This study was undertaken to develop and evaluate alternative materials and innovative designs for HEPA filters, making them more compatible with volume reduction technology. The following treatment options were selected for this study: 1) no treatment; 2) compaction; 3) supercompaction; 4) incinerate and melt; and 5) separate the frame from the media and dispose of the frame as low-level waste, and incinerate and melt the filter media and sealant. Forty HEPA design concepts were identified and evaluated by means of a figure-of-merit methodology for technical performance and an economic evaluation that considered filter fabrication and disposal costs. Results of the study indicate that if improved HEPA designs are combined with volume reduction treatments, the costs of filter disposal can be reduced substantially over the use of standard-flow filter designs with no volume reduction treatment. It is estimated that by combining the new design concepts with waste volume reduction treatments, manufacturing and disposal costs can be reduced by $290 or more per filter if classified as low-level waste (LLW) and up to $23,000 per filter if it is high-activity waste (containing activity greater than class-C LLW) and requires repository disposal
Finite-Frequency Filter Design for Networked Control Systems with Missing Measurements
Dan Ye; Yue Long; Guang-Hong Yang
2013-01-01
This paper is concerned with the problem of robust filter design for networked control systems (NCSs) with random missing measurements. Different from existing robust filters, the proposed one is designed in finite-frequency domain. With consideration of possible missing data, the NCSs are first modeled to Markov jump systems (MJSs). A finite-frequency stochastic H∞ performance is subsequently given that extends the standard H∞ performance, and then a sufficient condition guaranteeing the ...
A design methodology for delta-sigma converters based on solid-state passive filters
Benabes, Philippe
2013-01-01
Print ISBN : 978-1-4799-0618-5 International audience In the context in the ENIAC ARTEMOS project for the design of agile radio front ends, this paper shows a methodology for the design of agile bandpass continuous-time delta sigma based on acoustic tunable resonators. These resonators use BST materials which have the property to be tunable by an external voltage, allowing changing the resonance frequency of filters by a few percent. Using such filters, the Oversampling ratio of delta s...
VHDL Design for Image Segmentation using Gabor filter for Disease Detection
Directory of Open Access Journals (Sweden)
Rucha R. Thakur
2012-04-01
Full Text Available Tonsillitis, Tumor and many more skin diseases can be detected in its early-state and can be cured. For this a new idea for efficient Gabor filter design with improved data transfer rate, efficient noise reduction, less power consumption and reduced memory usage is proposed in this paper. The filter design is suitable for detecting the early stages of disease using textural properties of anatomical structures. The code for Gabor filter will be developed in VHDL using Model sim and then implemented on SPARTAN-3E FPGA kit. These systems must provide both highly accurate and extremely fast processing of large amounts of image data.
Design and control of an LCL-filter-based three-phase active rectifier
DEFF Research Database (Denmark)
Liserre, Marco; Blaabjerg, Frede; Hansen, Steffan
2005-01-01
This paper proposes a step-by-step procedure for designing the LCL filter of a front-end three-phase active rectifier. The primary goal is to reduce the switching frequency ripple at a reasonable cost, while at the same time achieving a high-performance front-end rectifier (as characterized by a...... powerful tool to design an LCL-filter-based active rectifier while avoiding trial-and-error procedures that can result in having to build several filter prototypes....
The design of a 4’th order Bandpass Butterworth filter with one operational amplifier
DEFF Research Database (Denmark)
Gaunholt, Hans
2008-01-01
A numerical design method is presented for the design of all pole band pass active-RC filters applying just one operational amplifier. The operational amplifier model used is the integrator model: ωt/s where ωt is the unity gain fre-quency. The design method is used for the design of a fourth order...... band pass filter with Butterworth poles applying just one operational amplifier coupled as a unity gain amplifier. The unity gain amplifiers have the advantage of providing low power consumption, yielding a large dynamic range, sometimes simplifying the amplifier design and being usable over a larger...
Design of Filters for COMPASS Thomson Scattering Diagnostics
Czech Academy of Sciences Publication Activity Database
Aftanas, Milan; Scannell, R.; Bílková, Petra; Böhm, Petr; Weinzettl, Vladimír; Walsh, M.
Vol. 2. Prague : MATFYZPRESS, Prague, 2009 - (Šafránková, J.; Pavlů, J.), s. 144-147 ISBN 978-80-7378-102-6. [Annual conference of doctoral students - WDS 2009 /18./. Prague (CZ), 02.06.2009-05.06.2009] R&D Projects: GA ČR GD202/08/H057 Institutional research plan: CEZ:AV0Z20430508 Keywords : Thomson scattering * COMPASS * filters Subject RIV: BL - Plasma and Gas Discharge Physics http://www.mff.cuni.cz/veda/konference/wds/contents/pdf09/WDS09_224_f2_Aftanas.pdf
Design of Maximally Flat FIR Filters Based on Explicit Formulas Combined with Optimization
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
A maximally flat FIR filter design method based on explicit formulas combined with simulated annealing and random search was presented. Utilizing the explicit formulas to calculate the initial values, the finite-word-length FIR filter design problem was converted into optimization of the filter coefficients. An optimization method combined with local discrete random search and simulated annealing was proposed, with the result of optimum solution in the sense of Chebyshev approximation. The proposed method can simplify the design process of FIR filter and reduce the calculation burden. The simulation result indicates that the proposed method is superior to the traditional round off method and can reduce the value of the objective function to 41%-74%.
Radiation field characterization of a BNCT research facility using Monte Carlo Method - Code MCNP-4B
International Nuclear Information System (INIS)
Boron Neutron Capture Therapy - BNCT- is a selective cancer treatment and arises as an alternative therapy to treat cancer when usual techniques - surgery, chemotherapy or radiotherapy - show no satisfactory results. The main proposal of this work is to project a facility to BNCT studies. This facility relies on the use of an AmBe neutron source and on a set of moderators, filters and shielding which will provide the best neutron/gamma beam characteristic for these BNCT studies, i.e., high intensity thermal and/or epithermal neutron fluxes and with the minimum feasible gamma rays and fast neutrons contaminants. A computational model of the experiment was used to obtain the radiation field in the sample irradiation position. The calculations have been performed with the MCNP 4B Monte Carlo Code and the results obtained can be regarded as satisfactory, i.e., a thermal neutron fluency ΝΤ = 1,35x108 n/cm2, a fast neutron dose of 5,86x-10 Gy/ΝΤ and a gamma ray dose of 8,30x-14 Gy/ΝΤ. (author)
Dybka, Kamil; Śmietana, Bartosz; Szarniak, Przemysław; Dłubek, Michał
2015-12-01
An engineering tool for designing LPG-based filters is reported. Band-rejection filters for telecom applications have been designed and manufactured and an automated mass production technology has been developed. The technology utilizes single-shot LPG writing with a double CO2 laser beam. The paper discusses also the critical process parameters controlled to shape the spectral characteristics of manufactured filters.
2010-10-01
... 42 Public Health 1 2010-10-01 2010-10-01 false DOP filter test; respirators designed as... filter test; respirators designed as respiratory protection against dusts, fumes, and mists having an air...) All single air-purifying respirator filter units will be tested in an atmosphere concentration of...
A numerical design approach for single amplifier, Active-RC Butterworth filter of order 5
DEFF Research Database (Denmark)
Gaunholt, Hans
2007-01-01
A design method is presented for the design of all pole lowpass active-RC filters applying operational amplifiers. The operational amplifier model used is the integrator model: omegat/s where omegat is the unity gain frequency. The design method is used for the design of a fifth order Butterworth...... filter applying just one operational amplifier coupled as a unity gain amplifier. It is shown that the influence from the real operational amplifier may be reduced by trimming just one resistor in the circuit. The unity gain amplifiers have the advantage of providing low power consumption, yielding...... a large dynamic range, sometimes simplifying the amplifier design and being usable over a larger frequency range than conventional constant gain amplifiers. The Schoeffler sensitivity index is used as a basis for a sensitivity comparison with other similar filters reported in the literature. © 2007 IEEE....
Hybrid method for designing digital FIR filters based on fractional derivative constraints.
Baderia, Kuldeep; Kumar, Anil; Kumar Singh, Girish
2015-09-01
In this manuscript, a hybrid approach based on Lagrange multiplier method and cuckoo search (CS) optimization technique is proposed for the design of linear phase finite impulse response (FIR) filters using fractional derivative constraints. In the proposed method, FIR filter is designed by optimizing the integral squares in passband and stopband from ideal response such that the fractional derivatives of designed filter response become zero at a given frequency point. Lagrange multiplier method is exploited for finding the optimized filter coefficients. Optimal value of fractional derivative constraints for optimized filter coefficients are determined by minimizing the objective function constructed using a sum of maximum passband ripple and maximum stopband ripple in frequency domain using CS algorithm. Performance of the proposed method is evaluated by passband error (ϕ(p)), stopband error (ϕ(s)), stopband attenuation (A(s)), maximum passband ripple (MPR), maximum stopband ripple (MSR) and CPU time. A comparative study of the performance of particle swarm optimization (PSO) and artificial bee colony (ABC) for designing FIR filters using the proposed method is also made. PMID:26142984
Multi-Bandwidth Frequency Selective Surfaces for Near Infrared Filtering: Design and Optimization
Cwik, Tom; Fernandez, Salvador; Ksendzov, A.; LaBaw, Clayton C.; Maker, Paul D.; Muller, Richard E.
1999-01-01
Frequency selective surfaces are widely used in the microwave and millimeter wave regions of the spectrum for filtering signals. They are used in telecommunication systems for multi-frequency operation or in instrument detectors for spectroscopy. The frequency selective surface operation depends on a periodic array of elements resonating at prescribed wavelengths producing a filter response. The size of the elements is on the order of half the electrical wavelength, and the array period is typically less than a wavelength for efficient operation. When operating in the optical region, diffraction gratings are used for filtering. In this regime the period of the grating may be several wavelengths producing multiple orders of light in reflection or transmission. In regions between these bands (specifically in the infrared band) frequency selective filters consisting of patterned metal layers fabricated using electron beam lithography are beginning to be developed. The operation is completely analogous to surfaces made in the microwave and millimeter wave region except for the choice of materials used and the fabrication process. In addition, the lithography process allows an arbitrary distribution of patterns corresponding to resonances at various wavelengths to be produced. The design of sub-millimeter filters follows the design methods used in the microwave region. Exacting modal matching, integral equation or finite element methods can be used for design. A major difference though is the introduction of material parameters and thicknesses tha_ may not be important in longer wavelength designs. This paper describes the design of multi-bandwidth filters operating in the I-5 micrometer wavelength range. This work follows on previous design [1,2]. In this paper extensions based on further optimization and an examination of the specific shape of the element in the periodic cell will be reported. Results from the design, manufacture and test of linear wedge filters built
Design of UWB Bandpass Filter with Notched Band Using Distributed CRLH Transmission Lines
Directory of Open Access Journals (Sweden)
Gyuje Sung
2015-08-01
Full Text Available This study presents an Ultra-Wideband (UWB filter with a notched band. The filter adopts novel Composite Right/Left-Handed (CRLH Transmission Lines (TLs, the unit cell of which is theoretically analyzed to derive the design formulas. A model of the CRLH TLs is composed with distributed elements rather than lumped elements. Based on the results of the analysis, it is confirmed that the proposed structures are CRLH TLs. A UWB bandpass filter with a notched band is designed and fabricated using the induced formulas. The measurement results show that the fabricated UWB bandpass filter has an insertion loss of less than 3 dB, a bandwidth of 2.8-10.5 GHz and a rejection of greater than 27 dB at 5.75 GHz.
Shunt hybrid active power filter for harmonic mitigation: A practical design approach
Indian Academy of Sciences (India)
Unnikrishnan A K; Chandira Sekaran E; Subhash Joshi T G; Manju A S; Aby Joseph
2015-06-01
The increasing importance of Power Quality problems has been responsible for several improvements in Active Power Filter (APF) typologies in the last decade. The increased cost and switching losses make a pure shunt APF economically impractical for high power applications. In higher power levels shunt Hybrid Active Power Filter (HAPF) has been reported to be a useful approach to eliminate current harmonics caused by nonlinear loads. This paper presents a control strategy and design criteria for transformer-less shunt HAPF with special attention to the integration of series passive filter. The paper also compares the performance improvement of passive harmonic filter when modified as shunt HAPF. Experimental results obtained verify the viability and effectiveness of the proposed design criteria and control algorithm.
Design of high-order elliptic filter from a versatile mode generic OTA-C structure
Ghosh, K.; Ray, B. N.
2015-03-01
A new synthesis methodology for high-order versatile mode programmable Operational transconductance amplifier and capacitor (OTA-C) generic filter structure is proposed. The structure fulfills the three main criteria of high frequency operation i.e it uses (1) less number of components (2) only single ended input OTAs (3) only grounded capacitors. Any nth order transfer function can be realised from it. Elliptic filter is designed from the generic structure using optimisation technique to reduce the number of OTAs. SPICE simulation with BSIM level 53 model and 0.13 μm process confirms the theoretical analysis. Frequency response of third-order and fourth-order elliptic filter is shown as representative set of simulated result. Sensitivity and non-ideal effect of the designed filter are studied.
Zhang, Ziye; Lin, Chong; Chen, Bing
2015-12-01
In this paper, the problem of H∞ filter design for nonlinear interconnected systems with time-varying delays through Takagi-Sugeno fuzzy models is revisited. Based on the fuzzy line-integral Lyapunov function approach and the reciprocally convex inequality, a delay-dependent decentralized H∞ filter is designed by guaranteeing the asymptotic stability and a prescribed H∞ performance index for the overall filter error system. A new sufficient condition for the existence of such a filter is established in terms of linear matrix inequalities. The present method provides improvements and produces better results than existing ones in the literature. Two examples are given to show the advantages and effectiveness of the proposed results. PMID:25616093
Design of Substrate Integrated Waveguide Pass Filter at [33-75] GHz Band
Ahmed Rhbanou; Seddik Bri
2014-01-01
This article presented the design of two filters SIW (Substrate Integrated Waveguide) in two different bands. Their conceptions were made by two different topologies. The first SIW filter with circular inductive post in the band [33-50] GHz on an RT / Duroid 5880 substrate permittivity 2.2, the simulated results of this filter have shown that the insertion loss lower than -0.4 dB within 3.5% bandwidth around 41.7 GHz and the return loss is better than -15 dB between 41.1 GHz and 42.4 GH...
Energy Technology Data Exchange (ETDEWEB)
Ana J. Molinari; Emiliano C. C. Pozzi; Andrea Monti Hughes; Elisa M. Heber; Marcela A. Garabalino; Silvia I. Thorp; Marcelo Miller; Maria E. Itoiz; Romina F. Aromando; David W. Nigg; Jorge Quintana; Gustavo A. Santa Cruz; Veronica A. Trivillin; Amanda E. Schwint
2011-04-01
In the present study we evaluated the therapeutic effect and/or potential radiotoxicity of the novel “Tandem” Boron Neutron Capture Therapy (T-BNCT) for the treatment of oral cancer in the hamster cheek pouch model at RA-3 Nuclear Reactor. Two groups of animals were treated with “Tandem BNCT”, i.e. BNCT mediated by boronophenylalanine (BPA) followed by BNCT mediated by sodium decahydrodecaborate (GB-10) either 24 h (T-24h-BNCT) or 48 h (T-48h-BNCT) later. A total tumor dose-matched single application of BNCT mediated by BPA and GB-10 administered jointly [(BPA + GB-10)-BNCT] was administered to an additional group of animals. At 28 days post-treatment, T-24h-BNCT and T-48h-BNCT induced, respectively, overall tumor control (OTC) of 95% and 91%, with no statistically significant differences between protocols. Tumor response for the single application of (BPA + GB-10)-BNCT was 75%, significantly lower than for T-BNCT. The T-BNCT protocols and (BPA + GB-10)-BNCT induced reversible mucositis in dose-limiting precancerous tissue around treated tumors, reaching Grade 3/4 mucositis in 47% and 60% of the animals respectively. No normal tissue radiotoxicity was associated to tumor control for any of the protocols. “Tandem” BNCT enhances tumor control in oral cancer and reduces or, at worst, does not increase, mucositis in dose-limiting precancerous tissue.
On Implementation and Design of Filter Banks for Subband Adaptive Systems
Weiss, S; Harteneck, M; Stewart, R W
1998-01-01
This paper introduces a polyphase implementation and design of an oversampled K-channel generalized DFT (GDFT) filter bank, which can be employed for subband adaptive filtering, and therefore is required to have a low aliasing level in the subband signals. A polyphase structure is derived which can be factorized into a real valued polyphase network and a GDFT modulation. For the latter, an FFT realization may be used, yielding a highly efficient polyphase implementation for arbitrary integer ...
O'Callaghan, Finbarr; Bitauld, David; O'Brien, Stephen
2014-01-01
We consider design optimization of passively mode-locked two-section semiconductor lasers that incorporate intracavity grating spectral filters. Our goal is to develop a method for finding the optimal wavelength location for the filter in order to maximize the region of stable mode-locking as a function of drive current and reverse bias in the absorber section. In order to account for material dispersion in the two sections of the laser, we use analytic approximations for the gain and absorpt...
REGRESSION MODELS ON DESIGN AND OPERATIONAL PARAMETERS OF SLOW SAND FILTERS
Aydin, Mehmet Emin
1996-01-01
The aim of this research was to obtain a regression model that relates the design and operational parameters and inflow water quality for slow sand filters. Therefore, three laboratory scale slow sand filters with sands of different effective diameters were operated at three different temperatures and at five flow rates. Stream water was used as inflow. Small quantities of settled sewage were added to the feed water. From the data produced, 72 regression models were developed relating inflow ...
Directory of Open Access Journals (Sweden)
Nouri Keltouma
2011-11-01
Full Text Available Microstrip tapered transition and inductive band-pass filter around 5 GHz, using Substrate Integrated Waveguide technology (SIW are studied in this paper. All the structures are designed with Finite Element Method (FEM and fabricated on a single substrate of Epoxy FR4 using a standard PCB process. The return loss of the proposed filter is better than 20 dB. The measured results for all the structures investigated show a good agreement with the simulation results.
Nouri Keltouma; Feham Mohammed; Adnan Saghir
2011-01-01
Microstrip tapered transition and inductive band-pass filter around 5 GHz, using Substrate Integrated Waveguide technology (SIW) are studied in this paper. All the structures are designed with Finite Element Method (FEM) and fabricated on a single substrate of Epoxy FR4 using a standard PCB process. The return loss of the proposed filter is better than 20 dB. The measured results for all the structures investigated show a good agreement with the simulation results.
RF MEMS and CSRRs-based tunable filter designed for Ku and K bands application
Ngasepam Monica Devi; Santanu Maity; Rajesh Saha; Sanjeev Kumar Metya
2015-01-01
This paper presents the design and simulation of a reconfigurable stop-band filter on a silicon substrate based on the combination of RF microelectromechanical system and metamaterial-based technologies. The device is implemented on coplanar waveguide structure by embedding complementary split-ring resonators on the central line and an RF MEMS varactor bridge supporting the neighboring ground planes. The response characteristics of this metamaterial-based filter can be dynamically tuned, thus...
CSD-Coded Genetic Algorithm on Robustly Stable Multiplierless IIR Filter Design
Shing-Tai Pan
2012-01-01
A Canonic-Signed-Digit-(CSD-) coded genetic algorithm (GA) is proposed to find the optimal design of robustly stable infinite impulse response digital filter (IIR). Under the characteristics of the CSD structure, the circuit of the filter can be simplified and also the calculation speed can be raised to increase the hardware’s efficiency. However, the design of CSD has a big challenge: the CSD structure of the system parameters will be destroyed by an optimal design procedure. To solve this p...
Passivity-based design of robust passive damping for LCL-filtered voltage source converters
DEFF Research Database (Denmark)
Wang, Xiongfei; Blaabjerg, Frede; Loh, Poh Chiang
2015-01-01
Passive damping is proven as a robust stabilizing technique for LCL-filtered voltage source converters. However, conventional design methods of passive dampers are based on the passive components only, while the inherent damping effect of time delay in the digital control system is overlooked. In...... this paper, a frequency-domain passivity-based design approach is proposed, where the passive dampers are designed to eliminate the negative real part of the converter output admittance with closed-loop current control, rather than shaping the LCL-filter itself. Thus, the influence of time delay in the...
Filter Design and Performance Evaluation for Fingerprint Image Segmentation
Thai, Duy Hoang; Huckemann, Stephan; Gottschlich, Carsten
2016-01-01
Fingerprint recognition plays an important role in many commercial applications and is used by millions of people every day, e.g. for unlocking mobile phones. Fingerprint image segmentation is typically the first processing step of most fingerprint algorithms and it divides an image into foreground, the region of interest, and background. Two types of error can occur during this step which both have a negative impact on the recognition performance: ‘true’ foreground can be labeled as background and features like minutiae can be lost, or conversely ‘true’ background can be misclassified as foreground and spurious features can be introduced. The contribution of this paper is threefold: firstly, we propose a novel factorized directional bandpass (FDB) segmentation method for texture extraction based on the directional Hilbert transform of a Butterworth bandpass (DHBB) filter interwoven with soft-thresholding. Secondly, we provide a manually marked ground truth segmentation for 10560 images as an evaluation benchmark. Thirdly, we conduct a systematic performance comparison between the FDB method and four of the most often cited fingerprint segmentation algorithms showing that the FDB segmentation method clearly outperforms these four widely used methods. The benchmark and the implementation of the FDB method are made publicly available. PMID:27171150
Energy Technology Data Exchange (ETDEWEB)
Eroglu, Abdullah [ORNL
2010-01-01
Triple band microstrip tri-section bandpass filter using stepped impedance resonators (SIRs) is designed, simulated, built, and measured using hair pin structure. The complete design procedure is given from analytical stage to implementation stage with details The coupling between SIRs is investigated for the first time in detail by studying their effect on the filter characteristics including bandwidth, and attenuation to optimize the filter perfomance. The simulation of the filler is performed using method of moment based 2.5D planar electromagnetic simulator The filter is then implemented on RO4003 material and measured The simulation, and measured results are compared and found to be my close. The effect of coupling on the filter performance is then investigated using electromagnetic simulator It is shown that the coupling effect between SIRs can be used as a design knob to obtain a bandpass Idler with a better performance jar the desired frequency band using the proposed filter topology The results of this work can used in wireless communication systems where multiple frequency bandy are needed
An Improved Variable Structure Adaptive Filter Design and Analysis for Acoustic Echo Cancellation
Directory of Open Access Journals (Sweden)
A. Kar
2015-04-01
Full Text Available In this research an advance variable structure adaptive Multiple Sub-Filters (MSF based algorithm for single channel Acoustic Echo Cancellation (AEC is proposed and analyzed. This work suggests a new and improved direction to find the optimum tap-length of adaptive filter employed for AEC. The structure adaptation, supported by a tap-length based weight update approach helps the designed echo canceller to maintain a trade-off between the Mean Square Error (MSE and time taken to attain the steady state MSE. The work done in this paper focuses on replacing the fixed length sub-filters in existing MSF based AEC algorithms which brings refinements in terms of convergence, steady state error and tracking over the single long filter, different error and common error algorithms. A dynamic structure selective coefficient update approach to reduce the structural and computational cost of adaptive design is discussed in context with the proposed algorithm. Simulated results reveal a comparative performance analysis over proposed variable structure multiple sub-filters designs and existing fixed tap-length sub-filters based acoustic echo cancellers.
Design of Digital IIR Filter with Conflicting Objectives Using Hybrid Gravitational Search Algorithm
Directory of Open Access Journals (Sweden)
D. S. Sidhu
2015-01-01
Full Text Available In the recent years, the digital IIR filter design as a single objective optimization problem using evolutionary algorithms has gained much attention. In this paper, the digital IIR filter design is treated as a multiobjective problem by minimizing the magnitude response error, linear phase response error and optimal order simultaneously along with meeting the stability criterion. Hybrid gravitational search algorithm (HGSA has been applied to design the digital IIR filter. GSA technique is hybridized with binary successive approximation (BSA based evolutionary search method for exploring the search space locally. The relative performance of GSA and hybrid GSA has been evaluated by applying these techniques to standard mathematical test functions. The above proposed hybrid search techniques have been applied effectively to solve the multiparameter and multiobjective optimization problem of low-pass (LP, high-pass (HP, band-pass (BP, and band-stop (BS digital IIR filter design. The obtained results reveal that the proposed technique performs better than other algorithms applied by other researchers for the design of digital IIR filter with conflicting objectives.
Reliability-Oriented Design of LC Filter in Buck DC-DC Converter
DEFF Research Database (Denmark)
Liu, Yi; Huang, Meng; Wang, Huai; Zha, Xiaoming; Gong, Jinwu; Sun, Jianjun
design of the LC filters from a reliability perspective, among other considerations. It investigates the design freedom between the values of inductor and capacitors, the physical formation of the LC network, and the corresponding electro-thermal stresses of the selected capacitors. The outcome enables...
Energy Technology Data Exchange (ETDEWEB)
Bergman, W.; First, M.W.; Anderson, W.L. [Lawrence Livermore National Laboratory, CA (United States)] [and others
1995-02-01
We have reviewed the literature on the performance of HEPA filters under normal and abnormal conditions to establish criteria for calculating the efficiency of HEPA filters in a DOE nonreactor nuclear facility during and after a Design Basis Accident (DBA). This study is only applicable to the standard deep-pleated HEPA filter with aluminum separators as specified in ASME N509[1]. Other HEPA filter designs such as the mini-pleat and separatorless filters are not included in this study. The literature review included the performance of new filters and parameters that may cause deterioration in the filter performance such as filter age, radiation, corrosive chemicals, seismic and rough handling, high temperature, moisture, particle clogging, high air flow and pressure pulses. The deterioration of the filter efficiency depends on the exposure parameters; in severe exposure conditions the filter will be damaged and have a residual efficiency of 0%. There are large gaps and limitations in the data that introduce significant error in the estimates of HEPA filter efficiencies under DBA conditions. Because of this limitation, conservative values of filter efficiency were chosen. The estimation of the efficiency of the HEPA filters under DBA conditions involves three steps: (1) The filter pressure drop and environmental parameters are determined during and after the DBA, (2) Comparing the filter pressure drop to a set of threshold values above which the filter is damaged. There is a different threshold value for each combination of environmental parameters, and (3) Determining the filter efficiency. If the filter pressure drop is greater than the threshold value, the filter is damaged and is assigned 0% efficiency. If the pressure drop is less, then the filter is not damaged and the efficiency is determined from literature values of the efficiency at the environmental conditions.
International Nuclear Information System (INIS)
We have reviewed the literature on the performance of HEPA filters under normal and abnormal conditions to establish criteria for calculating the efficiency of HEPA filters in a DOE nonreactor nuclear facility during and after a Design Basis Accident (DBA). This study is only applicable to the standard deep-pleated HEPA filter with aluminum separators as specified in ASME N509[1]. Other HEPA filter designs such as the mini-pleat and separatorless filters are not included in this study. The literature review included the performance of new filters and parameters that may cause deterioration in the filter performance such as filter age, radiation, corrosive chemicals, seismic and rough handling, high temperature, moisture, particle clogging, high air flow and pressure pulses. The deterioration of the filter efficiency depends on the exposure parameters; in severe exposure conditions the filter will be damaged and have a residual efficiency of 0%. There are large gaps and limitations in the data that introduce significant error in the estimates of HEPA filter efficiencies under DBA conditions. Because of this limitation, conservative values of filter efficiency were chosen. The estimation of the efficiency of the HEPA filters under DBA conditions involves three steps: (1) The filter pressure drop and environmental parameters are determined during and after the DBA, (2) Comparing the filter pressure drop to a set of threshold values above which the filter is damaged. There is a different threshold value for each combination of environmental parameters, and (3) Determining the filter efficiency. If the filter pressure drop is greater than the threshold value, the filter is damaged and is assigned 0% efficiency. If the pressure drop is less, then the filter is not damaged and the efficiency is determined from literature values of the efficiency at the environmental conditions
The Argonne ACWL, a potential accelerator-based neutron source for BNCT
International Nuclear Information System (INIS)
THE CWDD (Continuous Wave Deuterium Demonstrator) accelerator was designed to accelerate 80 mA cw of D- to 7.5 MeV. Most of the hardware for the first 2 MeV was installed at Argonne and major subsystems had been commissioned when program funding from the Ballistic Missile Defense Organization ended in October 1993. Renamed the Argonne Continuous Wave Linac (ACWL), we are proposing to complete it to accelerate either deuterons to 2 MeV or protons to 3-3.5 MeV. Equipped with a beryllium or other light-element target, it would make a potent source of neutrons (on the order of 1013 n/s) for BNCT and/or neutron radiography. Project status and proposals for turning ACWL into a neutron source are reviewed, including the results of a computational study that was carried out to design a target/moderator to produce an epithermal neutron beam for BNCT. (orig.)
Beam shaping assembly optimization for 7Li(p,n)7Be accelerator based BNCT
International Nuclear Information System (INIS)
Within the framework of accelerator-based BNCT, a project to develop a folded Tandem-ElectroStatic-Quadrupole accelerator is under way at the Atomic Energy Commission of Argentina. The proposed accelerator is conceived to deliver a proton beam of 30 mA at about 2.5 MeV. In this work we explore a Beam Shaping Assembly (BSA) design based on the 7Li(p,n)7Be neutron production reaction to obtain neutron beams to treat deep seated tumors. - Highlights: • A Beam Shaping Assembly for accelerator based BNCT has been designed. • A conical port for easy patient positioning and the cooling system are included. • Several configurations can deliver tumor doses greater than 55 RBEGy. • Good tumor doses can be obtained in less than 60 min of irradiation time
Determination of the irradiation field at the research reactor TRIGA Mainz for BNCT.
Nagels, S; Hampel, G; Kratz, J V; Aguilar, A L; Minouchehr, S; Otto, G; Schmidberger, H; Schütz, C; Vogtländer, L; Wortmann, B
2009-07-01
For the application of the BNCT for the excorporal treatment of organs at the TRIGA Mainz, the basic characteristics of the radiation field in the thermal column as beam geometry, neutron and gamma ray energies, angular distributions, neutron flux, as well as absorbed gamma and neutron doses must be determined in a reproducible way. To determine the mixed irradiation field thermoluminescence detectors (TLD) made of CaF(2):Tm with a newly developed energy-compensation filter system and LiF:Mg,Ti materials with different (6)Li concentrations and different thicknesses as well as thin gold foils were used. PMID:19380234
The studsvik BNCT project: structure and the proposed protocols
International Nuclear Information System (INIS)
The BNCT facility at Studsvik is now ready for clinical trials. Scientific operations of the Studsvik BNCT project are overseen by the Scientific Advisory Board comprised of representatives of all major universities in Sweden. Furthermore, special task groups for clinical and preclinical studies have been formed to facilitate collaboration with academia and to assure the quality of the research. Proposed clinical Phase II trials for glioblastoma are sponsored by the Swedish National Neuro-Oncology Group and, initially, will involve two protocols: Protocol no.1. BNCT for glioblastoma patients who have not received any therapy other than surgery (including stereotactic biopsy only). Protocol no.2. BNCT as a palliative treatment for patients with recurrent glioblastoma following conventional therapies or BNCT. In both protocols, BPA, administered by a 6 hour i.v. infusion, will be used as the boron delivery agent. (author)
Subramanyam, Guru; VanKeuls, Fred W.; Miranda, Felix A.; Canedy, Chadwick L.; Aggarwal, Sanjeev; Venkatesan, Thirumalai; Ramesh, Ramamoorthy
2000-01-01
The correlation of electric field and critical design parameters such as the insertion loss, frequency ability return loss, and bandwidth of conductor/ferroelectric/dielectric microstrip tunable K-band microwave filters is discussed in this work. This work is based primarily on barium strontium titanate (BSTO) ferroelectric thin film based tunable microstrip filters for room temperature applications. Two new parameters which we believe will simplify the evaluation of ferroelectric thin films for tunable microwave filters, are defined. The first of these, called the sensitivity parameter, is defined as the incremental change in center frequency with incremental change in maximum applied electric field (EPEAK) in the filter. The other, the loss parameter, is defined as the incremental or decremental change in insertion loss of the filter with incremental change in maximum applied electric field. At room temperature, the Au/BSTO/LAO microstrip filters exhibited a sensitivity parameter value between 15 and 5 MHz/cm/kV. The loss parameter varied for different bias configurations used for electrically tuning the filter. The loss parameter varied from 0.05 to 0.01 dB/cm/kV at room temperature.
Jiang, Zhi Hao; Gregory, Micah D; Werner, Douglas H
2016-04-01
A compact circularly polarized (CP) integrated filtering antenna is reported for wearable biotelemetric devices in the 2.4 GHz ISM band. The design is based on a mutual synthesis of a CP patch antenna connected to a bandpass filter composed of coupled stripline open-loop resonators, which provides an integrated low-profile radiating and filtering module with a compact form factor of 0.44λ(0)×0.44λ(0)×0.04λ(0). The optimized filtering antenna is fabricated and measured, achieving an S11 < -14 dB, an axial ratio of less than 3 dB and gain higher than 3.5 dBi in the targeted ISM band. With the integrated filtering functionality, the antenna exhibits good out-of-band rejection over an ultra-wide frequency range of 1-6 GHz. Further full-wave simulations and experiments were carried out, verifying that the proposed filtering antenna maintains these desirable properties even when mounted in close proximity to the human body at different positions. The stable impedance performance and the simultaneous wide axial ratio and radiated power beam widths make it an ideal candidate as a wearable antenna for off-body communications. The additional integrated filtering functionality further improves utility by greatly reducing interference and crosstalk with other existing wireless systems. PMID:26186795
Energy Technology Data Exchange (ETDEWEB)
Comani, S [Department of Clinical Sciences and Bio-imaging, Chieti University (Italy); Mantini, D [Department of Informatics and Automation Engineering, Marche Polytechnic University, Ancona (Italy); Alleva, G [ITAB-Institute of Advanced Biomedical Technologies, University Foundation ' G. D' Annunzio' , Chieti University (Italy); Luzio, S Di [Department of Clinical Sciences and Bio-imaging, Chieti University (Italy); Romani, G L [Department of Clinical Sciences and Bio-imaging, Chieti University (Italy)
2005-12-07
The greatest impediment to extracting high-quality fetal signals from fetal magnetocardiography (fMCG) is environmental magnetic noise, which may have peak-to-peak intensity comparable to fetal QRS amplitude. Being an unstructured Gaussian signal with large disturbances at specific frequencies, ambient field noise can be reduced with hardware-based approaches and/or with software algorithms that digitally filter magnetocardiographic recordings. At present, no systematic evaluation of filters' performances on shielded and unshielded fMCG is available. We designed high-pass and low-pass Chebychev II-type filters with zero-phase and stable impulse response; the most commonly used band-pass filters were implemented combining high-pass and low-pass filters. The achieved ambient noise reduction in shielded and unshielded recordings was quantified, and the corresponding signal-to-noise ratio (SNR) and signal-to-distortion ratio (SDR) of the retrieved fetal signals was evaluated. The study regarded 66 fMCG datasets at different gestational ages (22-37 weeks). Since the spectral structures of shielded and unshielded magnetic noise were very similar, we concluded that the same filter setting might be applied to both conditions. Band-pass filters (1.0-100 Hz) and (2.0-100 Hz) provided the best combinations of fetal signal detection rates, SNR and SDR; however, the former should be preferred in the case of arrhythmic fetuses, which might present spectral components below 2 Hz.
Spatial filter lens design for the main laser of the National Ignition Facility
International Nuclear Information System (INIS)
The National Ignition Facility (NIF), being designed and constructed at Lawrence Livermore National Laboratory (LLNL), comprises 192 laser beams The lasing medium is neodymium in phosphate glass with a fundamental frequency (1ω) of 1 053microm Sum frequency generation in a pair of conversion crystals (KDP/KD*P) will produce 1 8 megajoules of the third harmonic light (3ω or λ=351microm) at the target The purpose of this paper is to provide the lens design community with the current lens design details of the large optics in the Main Laser This paper describes the lens design configuration and design considerations of the Main Laser The Main Laser is 123 meters long and includes two spatial filters one 13 5 meters and one 60 meters These spatial filters perform crucial beam filtering and relaying functions We shall describe the significant lens design aspects of these spatial filter lenses which allow them to successfully deliver the appropriate beam characteristic onto the target For an overview of NIF please see ''Optical system design of the National Ignition Facility,'' by R Edward English. et al also found in this volume
The epithermal neutron beam for BNCT under construction at TAPIRO: Physics
International Nuclear Information System (INIS)
A column to provide an epithermal neutron beam suitable for experimental and clinical BNCT is nearing completion at the TAPIRO reactor (ENEA Casaccia, Rome). TAPIRO is a compact, low power (5 kW), helium-cooled, fast reactor. It has a hard neutron spectrum relative even to other fast reactors. In this paper some of the basic physics aspects of designing an epithermal neutron beam are considered, with reference to the TAPIRO beam
FIR Filter Design Using An Adjustable Novel Window and Its Applications
Directory of Open Access Journals (Sweden)
Hrishi Rakshit
2015-08-01
Full Text Available In this paper, a new class of adjustable window function, based on combination of tangent hyperbolic function and a weighted cosine series, is proposed to design an FIR filter. The proposed window is adjustable since the spectral characteristics of the window vary with the change of a simple window’s controlling parameter. The spectral characteristic of the proposed window is studied and its performance is compared with Hamming and Kaiser windows. Simulation results show that the proposed window yields better ripple and side-lobe roll-off ratios compare to the mentioned windows. Moreover, the paper represents the application of the proposed window in finite impulse response (FIR filter design. The results confirm that the filter designed by the proposed window provides 11.5607 dB better ripple ratio than Kaiser windows. In side-lobe roll-off ratio measurement, the proposed window based FIR low-pass filter attains 95.75 dB and 14.4534 dB better result than Hamming and Kaiser windows respectively. Moreover, the filter designed using the proposed window method reduces additive white Gaussian noise from the ECG signal more precisely than Kaiser window.
Kilbourne, Caroline A.; Adams, Joseph S.; Arsenovic, Petar; Ayers, Travis; Chiao, Meng P.; DiPirro, Michael J.; Eckart, Megan E.; Fujimoto, Ryuichi; Kazeva, John D.; Kelley, Richard L.; Kripps, Kari L.; Lairson, Bruce; Leutenegger, Maurice A.; McGuinness, Daniel S.; Porter, F. Scott; Schweiss, Andrea N.
2016-01-01
The calorimeter array of the JAXA Astro-H (renamed Hitomi) Soft X-ray Spectrometer (SXS) was designed to provide unprecedented spectral resolution of spatially extended cosmic x-ray sources and of all cosmic x-ray sources in the Fe-K band around 6 keV, enabling essential plasma diagnostics. The properties that make the SXS array a powerful x-ray spectrometer also make it sensitive to photons from the entire electromagnetic band, and particles as well. If characterized as a bolometer, it would have a noise equivalent power (NEP) of less than 4x10(exp -18) W/(Hz)0.5(exp 0.5). Thus it was imperative to shield the detector from thermal radiation from the instrument and optical and UV photons from the sky. Additionally, it was necessary to shield the coldest stages of the instrument from the thermal radiation emanating from the warmer stages. Both of these needs are addressed by a series of five thin-film radiation-blocking filters, anchored to the nested temperature stages, that block long-wavelength radiation while minimizing x-ray attenuation. The aperture assembly is a system of barriers, baffles, filter carriers, and filter mounts that supports the filters and inhibits their potential contamination. The three outer filters also have been equipped with thermometers and heaters for decontamination. We present the requirements, design, implementation, and performance of the SXS aperture assembly and blocking filters.
Li, Wei; Haese-Coat, Veronique; Ronsin, Joseph
1996-03-01
An adaptive GA scheme is adopted for the optimal morphological filter design problem. The adaptive crossover and mutation rate which make the GA avoid premature and at the same time assure convergence of the program are successfully used in optimal morphological filter design procedure. In the string coding step, each string (chromosome) is composed of a structuring element coding chain concatenated with a filter sequence coding chain. In decoding step, each string is divided into 3 chains which then are decoded respectively into one structuring element with a size inferior to 5 by 5 and two concatenating morphological filter operators. The fitness function in GA is based on the mean-square-error (MSE) criterion. In string selection step, a stochastic tournament procedure is used to replace the simple roulette wheel program in order to accelerate the convergence. The final convergence of our algorithm is reached by a two step converging strategy. In presented applications of noise removal from texture images, it is found that with the optimized morphological filter sequences, the obtained MSE values are smaller than those using corresponding non-adaptive morphological filters, and the optimized shapes and orientations of structuring elements take approximately the same shapes and orientations as those of the image textons.
Electromagnetic design methods in systems-on-chip: integrated filters for wireless CMOS RFICs
International Nuclear Information System (INIS)
We present general methods for designing on-chip CMOS passives and utilizing these integrated elements to design on-chip CMOS filters for wireless communications. These methods rely on full-wave electromagnetic numerical calculations that capture all the physics of the underlying foundry technologies. This is especially crucial for deep sub-micron CMOS technologies as it is important to capture the physical effects of finite (and mediocre) Q-factors limited by material losses and constraints on expensive die area, low self-resonance frequencies and dual parasitics that are particularly prevalent in deep sub-micron CMOS processes (65 nm-0.18 μm. We use these integrated elements in an ideal synthesis of a Bluetooth/WLAN pass-band filter in single-ended or differential architectures, and show the significant deviations of the on-chip filter response from the ideal one. We identify which elements in the filter circuit need to maximize their Q-factors and which Q-factors do not affect the filter performance. This saves die area, and predicts the FET parameters (especially transconductances) and negative-resistance FET topologies that have to be integrated in the filter to restore its performance. (invited paper)
Design and implementation of a low-pass filter for microsensor signal processing
Energy Technology Data Exchange (ETDEWEB)
Wang Zhuping; Zhong Shun' an; Ding Yingtao; Wang Xiaoqing, E-mail: wangzhuping169@163.com [School of Information and Electronics, Beijing Institute of Technology, Beijing 100081 (China)
2010-12-15
A novel low-pass filter that consists of a switched capacitor filter (SCF) and its antialiasing prefilter and smoothing postfilter is proposed for a microsensor signal processing system, which is used in separation point detection on the surface of micro air vehicles. In the system, the filter is not only applied to finish the function of filtering but also used as the front end antialiasing filter of the over sampling analog-to-digital converter. This proposed implementation mostly relies on the design of a high-precision SCF employing a correlated double sampling technique and optimisation switches. Simultaneously, the multiple-loop feedback low pass filter with good high frequency attenuation characteristics is applied as the pre- and postfilter. The design is implemented in the Central Semiconductor Manufacturing Corporation (CSMC) 0.5 {mu}m double-poly three-metal (2P3M) 3.3 V CMOS technology, with satisfactory results. The chip die area occupies only 0.39 mm{sup 2} and dissipates1.53 mW. (semiconductor integrated circuits)
Optical design and characterization of a gas filled MEMS Fabry-Perot filter
Ayerden, N. Pelin; Ghaderi, Mohammadamir; de Graaf, Ger; Wolffenbuttel, Reinoud F.
2015-05-01
A concept for a highly integrated and miniaturized gas sensor based on infrared absorption, a Fabry-Perot type linear variable optical filter with integrated gas cell, is presented. The sample chamber takes up most of the space in a conventional spectrometer and is the only component that has so far not been miniaturized. In this concept the gas cell is combined with the resonator cavity of the filter. The optical design, fabrication, and characterization results on a MEMSbased realization are reported for a 24-25.5 μm long tapered resonator cavity. Multiple reflections from highly reflective mirrors enable this optical cavity to also act as a gas cell with an equivalent optical absorption path length of 8 mm. Wideband operation of the filter is ensured by fabrication of a tapered mirror. In addition to the functional integration and significant size reduction, the filter contains no moving parts, thus enables the fabrication of a robust microspectrometer
Design of reproducible polarized and non-polarized edge filters using genetic algorithm
International Nuclear Information System (INIS)
Recent advancement in optical fibre communications technology is partly due to the advancement of optical thin film technology. The advancement of optical thin film technology includes the development of new and existing optical filter design methods. The genetic algorithm is one of the new design methods that show promising results in designing a number of complicated design specifications. It is the finding of this study that the genetic algorithm design method, through its optimization capability, can give more reliable and reproducible designs of any specifications. The design method in this study optimizes the thickness of each layer to get to the best possible solution. Its capability and unavoidable limitations in designing polarized and non-polarized edge filters from absorptive and dispersive materials is well demonstrated. It is also demonstrated that polarized and non-polarized designs from the genetic algorithm are reproducible with great success. This research has accomplished the great task of formulating a computer program using the genetic algorithm in a Matlab environment for the design of a reproducible polarized and non-polarized filters of any sort from any kind of materials
Bindiya T., S.; Elias, Elizabeth
2015-01-01
In this paper, multiplier-less near-perfect reconstruction tree-structured filter banks are proposed. Filters with sharp transition width are preferred in filter banks in order to reduce the aliasing between adjacent channels. When sharp transition width filters are designed as conventional finite impulse response filters, the order of the filters will become very high leading to increased complexity. The frequency response masking (FRM) method is known to result in linear-phase sharp transition width filters with low complexity. It is found that the proposed design method, which is based on FRM, gives better results compared to the earlier reported results, in terms of the number of multipliers when sharp transition width filter banks are needed. To further reduce the complexity and power consumption, the tree-structured filter bank is made totally multiplier-less by converting the continuous filter bank coefficients to finite precision coefficients in the signed power of two space. This may lead to performance degradation and calls for the use of a suitable optimisation technique. In this paper, gravitational search algorithm is proposed to be used in the design of the multiplier-less tree-structured uniform as well as non-uniform filter banks. This design method results in uniform and non-uniform filter banks which are simple, alias-free, linear phase and multiplier-less and have sharp transition width.
International Nuclear Information System (INIS)
This paper evaluates the potential of the Ohio State University (OSU) Research Reactor (OSURR) with a fission convertor plate (FCP) for clinical boron neutron capture therapy (BNCT). The evaluation uses design methods that were developed for the analysis of the OSU design of an accelerator-based neutron source (ABNS) for BNCT (hereafter called the OSU-ABNS); namely, the in-phantom neutron field assessment parameters, the treatment time (T) and the high-LET absorbed-dose to the tumor (DTumor), were calculated using MCNP. The paper compares an FCP epithermal neutron beam, which is based on the OSURR (hereafter called the OSURR-FCP) with the OSU-ABNS. For completeness, the comparison includes an alternative ABNS design, which was taken from the literature (hereafter called the 7LiF-Al2O3 ABNS), and the Brookhaven Medical Research Reactor (BMRR) epithermal neutron beam for BNCT (hereafter called the BMRR-ENB). The OSURR-FCP design consists of the OSURR, a fission plate, and a moderator/filter assembly. These components were modeled in MCNP. The OSURR is a 500-kW pool-type light water-cooled and moderated reactor that is reflected on two sides with graphite and uses a U3Si2-Al dispersion fuel. The fission plate and moderator/filter assembly, which were modeled, were identical to those specified by Liu. The goal of our analysis was not to perfect an FCP and moderator/filter assembly for the OSURR-FCP. Rather, the intent of our analysis was to determine if, using the FCP and moderator/filter assembly designed by Liu, the OSURR, operating at 100% power, could produce a beam of sufficient intensity to treat human patients with BNCT in a reasonable treatment time. T is the total time required for a BNCT treatment, including all treatment fractions. Since the total dose delivered to the tumor is limited by the tolerance of the surrounding normal tissue, T is defined as the time required to escalate the normal tissue RBE-dose to the tolerance of the normal brain. DTumor is the
Zhou, Jiafeng
2010-01-01
The general theory of microwave filter design based on lumped-element circuit is described in this chapter. The lowpass prototype filters with Butterworth, Chebyshev and quasielliptic characteristics are synthesized, and the prototype filters are then transformed to bandpass filters by lowpass to bandpass frequency mapping. By using immitance inverters ( J - or K -inverters), the bandpass filters can be realized by the same type of resonators. One design example is given to verify the theory ...
FIR 1 reactor in service for boron neutron capture therapy (BNCT) and isotope production
International Nuclear Information System (INIS)
Full text: The FIR 1-reactor, a 250 kW Triga reactor, has been in operation since 1962. The main purpose for the existence of the reactor is now the Boron Neutron Capture Therapy (BNCT). The BNCT work dominates the current utilization of the reactor: three or four days per week are reserved for BNCT purposes and the rest for other purposes such as isotope production and neutron activation analysis. In the 1990's a BNCT treatment facility was build at the FiR1 reactor located at Technical Research Centre of Finland. A special new neutron moderator material FluentalTM (Al+AlF3+Li) developed at VTT ensures the superior quality of the neutron beam. Also the treatment environment is of world top quality. The ground floor of the reactor hall was provided with a new entrance, easily accessible by any patient vehicle, a radio therapy control room and rooms for patient preparation and laboratories. The top of the reactor tank was separated from the reactor hall in order to confine contamination in case of a leakage from irradiation samples or fuel elements. The ventilation of the building, emergency power supply system, heat exchangers and the secondary cooling circuit of the reactor including cooling towers were completely redesigned and rebuilt. The expenditure of designing and accomplishing the construction work described was about 4 million euros. The costs were partly financed with venture capital via Radtek Ltd., particularly established for this enterprise. Close to thirty patients have been treated at FiR 1 since May 1999, when the license for patient treatment was granted to the responsible BNCT treatment organization, Boneca Corporation. VTT as the reactor operator has a long term contract with the Boneca Corp. to provide the facility and irradiation services for the patient treatments. The BNCT facility has been licensed for clinical use and is being surveyed by several national public health authorities including the Finnish Nuclear and Radiation Safety
A novel method for designing dichroic color filter transmittance curves for lighting applications
Qi, Rui; Shum, Frank
2014-09-01
This paper focuses on designing dichroic filters for changing the color of light-emitting diode (LED) lamps. Dichroic filters are composed of multiple dielectric layers on a substrate. By applying a dichroic filter, some of the LED's spectral energy is reflected and some is transmitted, which changes the lamp's color. Conventional methods to obtain spectral transmittance curves have shortcomings. The design criteria for the transmittance curves are incompatible with the metrics used in lighting applications, such as correlated color temperature (CCT) and color rendering index (CRI). Thus, the color rendering performance and the optical transmission of a lighting system are not optimized. This observation leads to the development of a proposed method for designing dichroic filter transmittance curves to provide accurate color shift, high CRI, and sufficient optical transmission. The method initially uses the transmittance curve of an existing color filter that provides a roughly close color shift for the LED lamp to calculate the transmittance curve that causes an accurate color shift by polynomial approximation. Based on the approximated curve, a preliminary transmittance curve without the effect of the LED lamp's secondary optics is derived and verified in thin-film design and optical design software tools. Further, the derived preliminary transmittance curve is optimized by applying an algorithm to loop through a large amount of representative curves fluctuating near the preliminary curve. The resulting dichroic filter provides an accurate color shift (ΔCCT = -800±50K, Duv = ±0.003), high CRI (Ra and R9 <= 95), and sufficient luminous flux transmission (<= 70%).
Optimal fractional delay-IIR filter design using cuckoo search algorithm.
Kumar, Manjeet; Rawat, Tarun Kumar
2015-11-01
This paper applied a novel global meta-heuristic optimization algorithm, cuckoo search algorithm (CSA) to determine optimal coefficients of a fractional delay-infinite impulse response (FD-IIR) filter and trying to meet the ideal frequency response characteristics. Since fractional delay-IIR filter design is a multi-modal optimization problem, it cannot be computed efficiently using conventional gradient based optimization techniques. A weighted least square (WLS) based fitness function is used to improve the performance to a great extent. FD-IIR filters of different orders have been designed using the CSA. The simulation results of the proposed CSA based approach have been compared to those of well accepted evolutionary algorithms like Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). The performance of the CSA based FD-IIR filter is superior to those obtained by GA and PSO. The simulation and statistical results affirm that the proposed approach using CSA outperforms GA and PSO, not only in the convergence rate but also in optimal performance of the designed FD-IIR filter (i.e., smaller magnitude error, smaller phase error, higher percentage improvement in magnitude and phase error, fast convergence rate). The absolute magnitude and phase error obtained for the designed 5th order FD-IIR filter are as low as 0.0037 and 0.0046, respectively. The percentage improvement in magnitude error for CSA based 5th order FD-IIR design with respect to GA and PSO are 80.93% and 74.83% respectively, and phase error are 76.04% and 71.25%, respectively. PMID:26391486
Shekhar Sharma; Sumant Katiyal; L. D. Arya
2015-01-01
For the optimal design of frequency-selective digital filters, evolutionary optimization algorithms have been applied. In these design methods the goal of the optimization process is to find the optimal filter coefficients which closely approximate the desired frequency response. In this paper, an efficient alternative method for the design of linear phase digital FIR filter with ripple constraint is discussed. This method of optimization uses DE algorithm with modified selection rule for rip...
The Phase I/II BNCT Trials at the Brookhaven medical research reactor: Critical considerations
International Nuclear Information System (INIS)
A phase I/II clinical trial of boronophenylalanine-fructose (BPA-F) mediated boron neutron capture therapy (BNCT) for Glioblastoma Multiforme (GBM) was initiated at Brookhaven National Laboratory (BNL) in 1994. Many critical issues were considered during the design of the first of many sequential dose escalation protocols. These critical issues included patient selection criteria, boron delivery agent, dose limits to the normal brain, dose escalation schemes for both neutron exposure and boron dose, and fractionation. As the clinical protocols progressed and evaluation of the tolerance of the central nervous system (CNS) to BPA-mediated BNCT at the BMRR continued new specifications were adopted. Clinical data reflecting the progression of the protocols will be presented to illustrate the steps taken and the reasons behind their adoption. (author)
Low-Cost Design of an FIR Filter by Using a Coefficient Mapping Method
Directory of Open Access Journals (Sweden)
Ming-Chih Chen
2013-01-01
Full Text Available This work presents a novel coefficient mapping method to reduce the area cost of the finite impulse response (FIR filter design, especially for optimizing its coefficients. Being capable of reducing the area cost and improving the filter performance, the proposed mapping method consists of four steps: quantization of coefficients, import of parameters, constitution of prime coefficients with parameters, and constitution of residual coefficients with prime coefficients. Effectiveness of the proposed coefficient mapping method is verified by selecting the 48-tap filter of IS-95 code division multiple access (CDMA standard as the benchmark. Experimental results indicate that the proposed design with canonical signed digit (CSD coefficients can operate at 86 MHz with an area of 241,813 um2, leading to a throughput rate of 1,382 Mbps. Its ratio of throughput/area is 5,715 Kbps/um2, yielding a higher performance than that of previous designs. In summary, the proposed design reduces 5.7% of the total filter area, shortens 25.7% of the critical path delay, and improves 14.8% of the throughput/area by a value over that of the best design reported before.
Carborane-containing metalloporphyrins for BNCT
International Nuclear Information System (INIS)
For BNCT of malignant brain tumors, it is crucial that there be relatively high boron concentrations in tumor compared with normal tissues within the neutron-irradiated treatment volume. Fairchild and Bond estimated that major advances in BNCT should be possible if ratios of 10B concentrations in tumor to those in normal tissue (e.g. brain and blood) were at least 5: 1. Given that the only current boron carrier being tested clinically in the U.S., p-boronophenyl-alanine[BPA], yields tumor blood and tumor brain ratios of about 3:1, the criteria for new boronated compounds should be to at least match these ratios and maintain tumor boron concentrations greater than 30 μg B/g. Although previously tested boronated porphyrins have not only matched but surpassed these ratios, it was at a cost of greater toxicity. Chemical and hematological assays of blood analytes; showed marked thrombocytopenia, a decrease to about one-tenth the normal concentration of platelets circulating in the blood, in addition to abnormalities in concentrations of circulating enzymes, that indicated liver toxicity. The physical appearance and behavior of the affected mice were different from those of mice injected with solvent only. Although thrombocytopenia and other toxic effects had disappeared after a few days, previously tested porphyrins would not be safe to infuse into patients for BNCT of potentially hemorrhagic malignant tumors in the brain such as glioblastoma multiforme and metastatic melanoma. We synthesized a different boronated porphyrin, tetracarboranylphenylporphyrin, [TCP] and inserted nickel, copper, or manganese into its coordination center. Biological studies of NiTCP in mice and of CuTCP in rats show that these compounds elicit little or no toxicity when given at potentially therapeutic doses
Carborane-containing metalloporphyrins for BNCT
Energy Technology Data Exchange (ETDEWEB)
Miura, Michiko; Joel, D.D.; Nawrocky, M.M.; Micca, P.L. [and others
1996-12-31
For BNCT of malignant brain tumors, it is crucial that there be relatively high boron concentrations in tumor compared with normal tissues within the neutron-irradiated treatment volume. Fairchild and Bond estimated that major advances in BNCT should be possible if ratios of {sup 10}B concentrations in tumor to those in normal tissue (e.g. brain and blood) were at least 5: 1. Given that the only current boron carrier being tested clinically in the U.S., p-boronophenyl-alanine[BPA], yields tumor blood and tumor brain ratios of about 3:1, the criteria for new boronated compounds should be to at least match these ratios and maintain tumor boron concentrations greater than 30 {mu}g B/g. Although previously tested boronated porphyrins have not only matched but surpassed these ratios, it was at a cost of greater toxicity. Chemical and hematological assays of blood analytes; showed marked thrombocytopenia, a decrease to about one-tenth the normal concentration of platelets circulating in the blood, in addition to abnormalities in concentrations of circulating enzymes, that indicated liver toxicity. The physical appearance and behavior of the affected mice were different from those of mice injected with solvent only. Although thrombocytopenia and other toxic effects had disappeared after a few days, previously tested porphyrins would not be safe to infuse into patients for BNCT of potentially hemorrhagic malignant tumors in the brain such as glioblastoma multiforme and metastatic melanoma. We synthesized a different boronated porphyrin, tetracarboranylphenylporphyrin, [TCP] and inserted nickel, copper, or manganese into its coordination center. Biological studies of NiTCP in mice and of CuTCP in rats show that these compounds elicit little or no toxicity when given at potentially therapeutic doses.
Clinical practice in BNCT to the brain
International Nuclear Information System (INIS)
Our concept of Boron Neutron Capture Therapy (BNCT) is to selectively destroy tumour cells using the high LET particles yielded from the 10B(n,α)7Li reactions. The effort of clinical investigators has concentrated on how to escalate the radiation dose at the target point. BNCT in Japan combines thermal neutrons and BSH (Na2B12H11SH). The radiation dose is determined by the neutron fluence at the target point and the boron concentration in the tumour tissue. According to the recent analysis, the ratio of boron concentration (BSH) in tumour tissue and blood is nearly stable at around 1.2 to 1.69. Escalation of the radiation dose was carried out by means of improving the penetration of the thermal neutron beam. Since 1968, 175 patients with glioblastoma (n=83), anaplastic astrocytoma (n=44), low grade astrocytoma (n=16) or other types of tumour (n=32) were treated by BNCT at 5 reactors (HTR n=13, JRR-3 n=1, MulTR n=98, KUR n=30, JRR-2 n=33). The retrospective analysis revealed that the important factors related to the clinical results and QOL of the patients were minimum tumour volume radiation dose, more than 18Gy of physical dose and maximum vascular radiation dose (less than 15Gy) in the normal cortex. We have planned several trials to escalate the target radiation dose. One trial makes use of a cavity in the cortex following debulking surgery of the tumour tissue to improve neutron penetration. The other trial is introduction of epithermal neutron. KUR and JRR-4 were reconstructed and developed to be able to irradiate using epithermal neutrons. The new combination of surgical procedure and irradiation using epithermal neutrons should remarkably improve the target volume dose compared to the radiation dose treated by thermal neutrons. (author)
Design and analysis of a high Q MEMS passive RF filter
Rathee, Vishal; Pande, Rajesh
2016-04-01
Over the past few years, significant growth has been observed in using MEMS based passive components in the RF microelectronics domain, especially in transceiver system. This is due to some excellent properties of the MEMS devices like low loss, low cost and excellent isolation. This paper presents a design of high performance MEMS passive band pass filter, consisting of L and C with improved quality factor and insertion loss less than the reported filters. In this paper we have presented a design of 2nd order band pass filter with 2.4GHz centre frequency and 83MHz bandwidth for Bluetooth application. The simulation results showed improved Q-factor of 34 and Insertion loss of 1.7dB to 1.9dB. The simulation results needs to be validated by fabricating the device, fabrication flow of which is also presented in the paper.
Design and performance of a high-Tc superconductor coplanar waveguide filter
Chew, Wilbert; Riley, A. L.; Rascoe, Daniel L.; Hunt, Brian D.; Foote, Marc C.; Cooley, Thomas W.; Bajuk, Louis J.
1991-01-01
The design of a coplanar waveguide low-pass filter made of YBa2Cu3O(7-delta) (YBCO) on an LaAlO3 substrate is described. Measurements were incorporated into simple models for microwave CAD analysis to develop a final design. The patterned and packaged coplanar waveguide low-pass filter of YBCO, with dimensions suited for integrated circuits, exhibited measured insertion losses when cooled in liquid nitrogen superior to those of a similarly cooled thin-film copper filter throughout the 0 to 9.5 GHz passband. Coplanar waveguide models for use with thin-film normal metal (with thickness either greater or less than the skin depth) and YBCO are discussed and used to compare the losses of the measured YBCO and copper circuits.
Design optimization of integrated BiDi triplexer optical filter based on planar lightwave circuit
Xu, Chenglin; Hong, Xiaobin; Huang, Wei-Ping
2006-05-01
Design optimization of a novel integrated bi-directional (BiDi) triplexer filter based on planar lightwave circuit (PLC) for fiber-to-the premise (FTTP) applications is described. A multi-mode interference (MMI) device is used to filter the up-stream 1310nm signal from the down-stream 1490nm and 1555nm signals. An array waveguide grating (AWG) device performs the dense WDM function by further separating the two down-stream signals. The MMI and AWG are built on the same substrate with monolithic integration. The design is validated by simulation, which shows excellent performance in terms of filter spectral characteristics (e.g., bandwidth, cross-talk, etc.) as well as insertion loss.
Mitigation of Noise in OFDM Based Plc System Using Filter Kernel Design
Directory of Open Access Journals (Sweden)
Nisha G Krishnan
2015-09-01
Full Text Available Power line communication is a technology that transforms power line in to pathway for conveyance of broadband data. It is cost less than other communication approach and for better bandwidth efficiency OFDM based PLC system is used. In real PLC environment some electrical appliances will produce noise. To mitigate this noise filter kernel design is used, so periodic impulsive noise and Gaussian noises are removed from PLC communication system by using this filter kernel design. MATLAB is used for the simulation and the result shows that filter kernel is simple and effective noise mitigation technique. Further in future, interference due to obstacles also wants to be mitigated for the better data transmission without noise.
Design and Simulation of a T-Type Lymphocyte Cells Filter on a Microfluidic System
Directory of Open Access Journals (Sweden)
Daniel A. Quiroga T.
2016-01-01
Full Text Available This work consisted in designing and validating, by experimental computational simulation, a T-Lymphocites filtering system based on microfluidics for hiv virus detection. Material and methods: It was used AutoDesk® Inventor simulation tool was used with which the microfluidic system design was performed. The filter system was tested by a computer simulation in the AutoDesk® Simulation cfd (computational fluid dynamics software, simulation tool in which different particles with different diameters (5 μm, 10 μm, 15 μm flow through the system to test. Results and conclusions: Results showed that this system allowed to pass the expected particles, however, it also was observed that it allows bigger particles than desired, for this reason it is necessary to keep on working on system perfectioning. Filtering system efficiency was of a 33.33 %.
Parallel power electronics filters in three-phase four-wire systems principle, control and design
Wong, Man-Chung; Lam, Chi-Seng
2016-01-01
This book describes parallel power electronic filters for 3-phase 4-wire systems, focusing on the control, design and system operation. It presents the basics of power-electronics techniques applied in power systems as well as the advanced techniques in controlling, implementing and designing parallel power electronics converters. The power-quality compensation has been achieved using active filters and hybrid filters, and circuit models, control principles and operational practice problems have been verified by principle study, simulation and experimental results. The state-of-the-art research findings were mainly developed by a team at the University of Macau. Offering background information and related novel techniques, this book is a valuable resource for electrical engineers and researchers wanting to work on energy saving using power-quality compensators or renewable energy power electronics systems. .
Energy Technology Data Exchange (ETDEWEB)
Shin, J.G. [LG Electronics, Seoul (Korea); Lee, T.H.; Park, J.B. [Yonsei University, Seoul (Korea); Yoon, T.S. [Changwon University, Changwon (Korea); Choi, Y.H. [Kyonggi University, Suwon (Korea)
2003-01-01
A Coordinate-Transformation Extended Robust Kalman Filter (CERKF) designed in the Krein space is proposed, and then applied to a nonlinear incoming ballistic missile tracking system with parameter uncertainties. First, the Extended Robust Kalman filter (ERKF) is proposed to handle the nonlinearity of measurement equation which occurs whenever the polar coordinate system is transformed into the Cartesian coordinate system. Moreover, linearization error inevitably occurs and deteriorates the tracking performance, which is considerably reduced by the proposed CERKF. Through the simulation results, we show that the proposed CERKF, which uses the measurement coordinate system, has less RMS error than the previous ERKF which is designed in the Krein space using the Cartesian system. We also verify that the robustness and the stability of the proposed filter are guaranteed in two radars: the phased array radar and the scanning radar. (author). 9 refs., 5 figs.
Design of Biquad Universal Filter Using Operational Transconductance Amplifier in 180nm Technology
Directory of Open Access Journals (Sweden)
Rahul Kumar,
2014-05-01
Full Text Available This paper presents concept of universal filter using operational transconductance amplifier (OTA.The 0.18μm CMOS process is used for design and simulation. This OTA has basing current of 50μA with supply voltage ±1.25v. The design and simulation of this OTA is done using CADENCE virtuoso environment with UMC 0.18μm technology file. This paper presents a electronically tunable voltage mode universal biquadratic filter with Three input and single output using two single ended OTA and two capacitors. The proposed filter provides low-pass,High-pass,Band-pass and Band-stop by appropriately connecting the input terminals. The natural frequency and the quality factor can be set orthogonally by adjusting the circuit components.Also the natural frequency can be electronically tuned via the bias currents of OTAs.
Design, fabrication and characterization of guided-mode resonance transmission filters
Amin, Mohammad Shyiq
This dissertation addresses photonic devices enabled by the guided-mode resonance (GMR) effect. As periodic phototonic structures can become highly reflective or transmissive at resonance, this effect has been utilized to design suites of optical elements including reflection filters, transmission filters, broadband mirrors, polarizers, and absorbers with a plethora of possible deployment venues. Even though there has been considerable research on the reflection type GMR elements, attendant transmission filters have less explored experimentally, as there is material limitation to design this kind of filters with simple architecture and they also may require coupling to multiple resonances simultaneously. Apart from the design issues, experimental realization of these filters is challenging. There have not been any experimental reports on optical transmission filters with narrow transmission band and high efficiency and well defined low sidebands. In this Dissertation, we design, fabricate and characterize narrow band guided-mode resonance transmission filters. Initially we study a way to engineer the optical constants of amorphous silicon (a-Si) suitable for different applications. Rapid thermal annealing is applied to induce crystallization of sputtered amorphous silicon deposited on thermally grown oxide layers. The influence of annealing temperatures in the range of 600°C--980°C is systematically investigated. Using scanning-electron microscopy, ellipsometry and x-ray diffraction techniques, the structural and optical properties of the films are determined. An order-of-magnitude reduction of the extinction coefficient is achieved. We show that the optical constants can be tuned for different design requirements by controlling the process parameters. For example, we obtain a refractive index of ~3.66 and an extinction coefficient of ~0.0012 at the 1550-nm wavelength as suitable for GMR transmission filter applications where a high refractive index and low
Stability margins in a design method for 2-dimensional recursive digital filters
Crebbin, G.; Attikiouzel, J.
1982-06-01
The present investigation is concerned with the extension of a concept of stability margin introduced by Crebbin and Attikiouzel (1981). When implemented as a constraint in a 2-D filter design problem, the stability margin guarantees stability, and, in addition, has a moderating effect on the behavior in either the frequency or the spatial domain. An investigation is conducted regarding the possibility of incorporating stability margins into available automated design methods, and a description is provided of a design method which uses the simplex algorithm reported by Nelder and Mead (1975). The considered algorithm is well suited to handle the constraints imposed by stability and by stability margins. Attention is given to filter structures, the design program, additional computing time for stability testing, problems of stable-only design methods, and relationships between pole position, frequency response, and spatial response.
Directory of Open Access Journals (Sweden)
SZOPOS, E.
2012-05-01
Full Text Available This paper presents an iterative method for designing FIR filters that implement arbitrary magnitude characteristics, defined by the user through a set of frequency-magnitude points (frequency samples. The proposed method is based on the non-uniform frequency sampling algorithm. For each iteration a new set of frequency samples is generated, by processing the set used in the previous run; this implies changing the samples location around the previous frequency values and adjusting their magnitude through interpolation. If necessary, additional samples can be introduced, as well. After each iteration the magnitude characteristic of the resulting filter is determined by using the non-uniform DFT and compared with the required one; if the errors are larger than the acceptable levels (set by the user a new iteration is run; the length of the resulting filter and the values of its coefficients are also taken into consideration when deciding a re-run. To demonstrate the efficiency of the proposed method a tool for designing FIR filters that match human audiograms was implemented in LabVIEW. It was shown that the resulting filters have smaller coefficients than the standard one, and can also have lower order, while the errors remain relatively small.
Directory of Open Access Journals (Sweden)
Yaqeen S Mezaal
Full Text Available This paper presents new Wide Bandpass Filter (WBPF and Narrow Bandstop Filter (NBSF incorporating two microstrip resonators, each resonator is based on 2nd iteration of Hilbert fractal geometry. The type of filter as pass or reject band has been adjusted by coupling gap parameter (d between Hilbert resonators using a substrate with a dielectric constant of 10.8 and a thickness of 1.27 mm. Numerical simulation results as well as a parametric study of d parameter on filter type and frequency responses are presented and studied. WBPF has designed at resonant frequencies of 2 and 2.2 GHz with a bandwidth of 0.52 GHz, -28 dB return loss and -0.125 dB insertion loss while NBSF has designed for electrical specifications of 2.37 GHz center frequency, 20 MHz rejection bandwidth, -0.1873 dB return loss and 13.746 dB insertion loss. The proposed technique offers a new alternative to construct low-cost high-performance filter devices, suitable for a wide range of wireless communication systems.
The PC-based ATLAS event filter prototype: supervision design, implementation and tests
International Nuclear Information System (INIS)
The studies undertaken to prepare the Technical Design Report of the ATLAS 3rd Level Trigger (Event Filter) are performed on different prototypes based on different technologies. The authors present here the most recent results obtained for the supervision of the prototype based on conventional, off-the-shelf PC machines and Java mobile agent technology
Design and operation of nitrifying trickling filters in recirculating aquaculture: a review
Eding, E.H.; Kamstra, A.; Verreth, J.A.J.; Huisman, E.A.; Klapwijk, A.
2006-01-01
This review deals with the main mechanisms and parameters affecting design and performance of trickling filters in aquaculture. Relationships between nitrification rates and easily accessible process parameters, like bulk phase concentration of TAN, O2, organic matter (COD), nitrite, temperature, HC
A New Method for Filter Design Based on Long-Period Fibre Grating
Institute of Scientific and Technical Information of China (English)
CHEN Kai; SHENG Qiu-Qin; DONG Xiao-Yi
2004-01-01
@@ We present a simple method to induce mechanically a long-period fibre grating in a general sing mode fibre. The transmission spectrum of the new type of grating can be tailored by changing the external applied pressure or by introducing a phase-shift in the grating. The tunability this kind of gratings exhibit will be particularly useful for the filter design.
Grid Filter Design for a Multi-Megawatt Medium-Voltage Voltage Source Inverter
DEFF Research Database (Denmark)
Rockhill, A.A.; Liserre, Marco; Teodorescu, Remus;
2011-01-01
converter, a limited allowable switching frequency, component physical size and weight concerns, and the stringent limits for allowable injected current harmonics. Traditional design procedures of grid filters for lower power and higher switching frequency converters are not valid for a multi...
Filter Design for Failure Detection and Isolation in the Presence of Modeling Erros and Disturbances
DEFF Research Database (Denmark)
Stoustrup, Jakob; Niemann, Hans Henrik
1996-01-01
The design problem of filters for robust Failure Detectionand Isolation, (FDI) is addressed in this paper. The failure detectionproblem will be considered with respect to both modeling errors anddisturbances. Both an approach based on failure detection observes aswell as an approach based...
DEFF Research Database (Denmark)
Niemann, Hans Henrik; Stoustrup, Jakob
1996-01-01
The design problem of filters for robust failure detection and isolation, (FDI) is addressed in this paper. The failure detection problem will be considered with respect to both modeling errors and disturbances. Both an approach based on failure detection observers as well as an approach based...
The PC—Based ATLAS Event Filter Prototype：Supervision Design,Implementation and Tests
Institute of Scientific and Technical Information of China (English)
C.P.Bee; F.Etienne; 等
2001-01-01
The studies undertaken to prepare the Technical Design Report of the ATLAS 3rd Level Trigger(Event Filter)are performed on different prototypes based on different technologies.we present here the most recent results obtained for the supervision of the prototype based on conventional,off-the-shelf PC machines and Java Moblie agent technology.
LC Filter Design for Wide Band Gap Device Based Adjustable Speed Drives
DEFF Research Database (Denmark)
Vadstrup, Casper; Wang, Xiongfei; Blaabjerg, Frede
This paper presents a simple design procedure for LC filters used in wide band gap device based adjustable speed drives. Wide band gap devices offer fast turn-on and turn-off times, thus producing high dV/dt into the motor terminals. The high dV/dt can be harmful for the motor windings and bearings...
International Nuclear Information System (INIS)
Author's group is carrying out development of BNCT-SPECT with CdTe device, which monitors the therapy effect of BNCT in real-time. From the design calculations, the dimensions were fixed to 1.5×2×30 mm3. For the collimator it was confirmed that it would have a good spatial resolution and simultaneously the number of counts would be acceptably large. After producing the CdTe crystal, the characterization measurement was carried out. For the detection efficiency an excellent agreement between calculation and measurement was obtained. Also, the detector has a very good energy resolution so that gamma-rays of 478 keV and 511 keV could be distinguished in the spectrum. - Highlights: • BNCT-SPECT is developed with CdTe device to estimate therapy effect of BNCT. • By design calculations, CdTe dimensions are determined to be 1.5×2×30 mm3. Collimator length is 10 cm with 2 mm diameter hole. • Producing the crystal, efficiency and energy resolution were measured. • Excellent agreement was obtained between measurement and calculation. Discrimination of 478 keV and 511 keV was confirmed in the spectrum
International Nuclear Information System (INIS)
There is a generalized perception that the availability of suitable particle accelerators installed in hospitals, as neutron sources, may be crucial for the advancement of Boron Neutron Capture Therapy (BNCT). An ongoing project to develop a Tandem-ElectroStatic-Quadrupole (TESQ) accelerator facility for Accelerator-Based (AB)-BNCT is described here. The project goal is a machine capable of delivering 30 mA of 2.4-2.5 MeV protons to be used in conjunction with a neutron production target based on the 7Li(p,n)7Be reaction slightly beyond its resonance at 2.25 MeV. A folded tandem, with 1.20-1.25 MV terminal voltage, combined with an ESQ chain is being designed and constructed. This machine is conceptually shown to be capable of accelerating a 30 mA proton beam to 2.5 MeV. These are the specifications needed to produce sufficiently intense and clean epithermal neutron beams, based on the 7Li(p,n)7Be reaction, to perform BNCT treatment for deep-seated tumors in less than an hour. This electrostatic machine is one of the technologically simplest and cheapest solutions for optimized AB-BNCT. At present there is no BNCT facility in the world with the characteristics presented in this work. For the accelerator, results on its design, construction and beam transport calculations are discussed. Taking into account the peculiarities of the expected irradiation field, the project also considers a specific study of the treatment room. This study aims at the design of the treatment room emphasizing aspects related to patient, personnel and public radiation protection; dose monitoring; patient positioning and room construction. The design considers both thermal (for the treatment of shallow tumors) and epithermal (for deep-seated tumors) neutron beams entering the room through a port connected to the accelerator via a moderation and neutron beam shaping assembly. Preliminary results of dose calculations for the treatment room design, using the MCNP program, are presented
An accelerator-based epithermal photoneutron source for BNCT
Energy Technology Data Exchange (ETDEWEB)
Nigg, D.W.; Mitchell, H.E.; Harker, Y.D.; Yoon, W.Y. [and others
1995-11-01
Therapeutically-useful epithermal-neutron beams for BNCT are currently generated by nuclear reactors. Various accelerator-based neutron sources for BNCT have been proposed and some low intensity prototypes of such sources, generally featuring the use of proton beams and beryllium or lithium targets have been constructed. This paper describes an alternate approach to the realization of a clinically useful accelerator-based source of epithermal neutrons for BNCT that reconciles the often conflicting objectives of target cooling, neutron beam intensity, and neutron beam spectral purity via a two stage photoneutron production process.
International Nuclear Information System (INIS)
The treatment of the malignant brain tumor through Boron Neutron Capture Therapy (BNCT) requires a high-flux neutron source. The Malaysian TRIGA Mark II reactor was investigated for a proposed BNCT facility. The neutron flux was measured along the central stringer of the thermal column and the outermost positions of the other stringers. The unfolding foil method was applied here. We have used Al, As, Au, Co, In, Mo, Ni and Re foils and Cd as a cover with 19 useful reactions in this study. The infinitely diluted foil activity was calculated and used in the SAND-II code (Spectrum Analysis by Neutron Detectors) to calculate the neutron flux. The reactor was also simulated using Monte Carlo code (MCNP5) and the neutron flux was calculated along the thermal column. The measured and calculated neutron flux along the thermal column show good agreement. The minimum epithermal neutron intensity required for BNCT is achieved up to position 22 with a mixed neutron-gamma beam. A suggested MCNP simulated modification of the reactor thermal column increased the neutron flux at distant positions from the reactor core but the epithermal neutron part was below the minimum requirement for a BNCT facility. The photon flux calculations along the thermal column show relatively high results which should be filtered. The calculation of the neutron and gamma dose in a head phantom (water) indicated that the available neutron spectrum requires modifications to increase the epithermal part of the neutrons and filter the gamma ray contamination. (author)
Big Bang–Big Crunch Optimization Algorithm for Linear Phase Fir Digital Filter Design
Ms. Rashmi Singh Dr. H. K. Verma
2012-01-01
The Big Bang–Big Crunch (BB–BC) optimization algorithm is a new optimization method that relies on the Big Bang and Big Crunch theory, one of the theories of the evolution of the universe. In this paper, a Big Bang–Big Crunch algorithm has been used here for the design of linear phase finite impulse response (FIR) filters. Here the experimented fitness function based on the mean squared error between the actual and the ideal filter response. This paper presents the plot of magnitude response ...
Tan, Hiang Teik; Hunter, Ian C.; Snowden, Christopher M.; Ranson, Richard
2005-01-01
This paper presents the first reported quarter-micron double delta doped AlGaAs/ InGaAs charge coupled device for microwave filter applications. The design and fabrication of conventional and multi tapped delay line MMICs for RF filter applications are also discussed. Schrödinger and Poisson’s equations are self consistently solved with current continuity equations to show the variation in channel charge concentration as the gate voltagesare varied. The device is implemented as a recessed cap...
Thermal Filters for the ATHENA X-IFU: Ongoing Activities Toward the Conceptual Design
Barbera, Marco; Argan, A.; Bozzo, E.; Branduardi-Raymont, G.; Ciaravella, A.; Collura, A.; Cuttaia, F.; Gatti, F.; Jimenez Escobar, A.; Lo Cicero, U.; Lotti, S.; Macculi, C.; Mineo, T.; Nuzzo, F.; Paltani, S.; Parodi, G.; Piro, L.; Rauw, G.; Sciortino, L.; Sciortino, S.; Villa, F.
2016-08-01
ATHENA is the L2 mission selected by ESA to pursue the science theme "Hot and Energetic Universe." One of the two focal plane instruments is the X-ray Integral Field Unit, an array of TES microcalorimeters operated at T thermal shields. X-ray transparent filters need to be mounted on these open windows to attenuate the IR radiation from warm surfaces, to attenuate RF electromagnetic interferences on TES sensors and SQUID electronics, and to protect the detector from contamination. This paper reviews the ongoing activities driving the design of the X-IFU thermal filters.
Park, Kihong
2013-02-01
In this paper, we study a two-hop relaying network consisting of one source, one destination, and three amplify-and-forward (AF) relays with multiple antennas. To compensate for the capacity prelog factor loss of 1/2$ due to the half-duplex relaying, alternate transmission is performed among three relays, and the inter-relay interference due to the alternate relaying is aligned to make additional degrees of freedom. In addition, suboptimal linear filter designs at the nodes are proposed to maximize the achievable sum rate for different fading scenarios when the destination utilizes a minimum mean-square error filter. © 1967-2012 IEEE.
The BNCT project in the Czech Republic
International Nuclear Information System (INIS)
The start of clinical trials is expected before NCT Osaka 2000. The experiences from different part of project are presented. The BNCT facility at LVR-15 reactor of NRI consists of epithermal neutron beam with improved construction (6.98 x 108/cm2s with acceptable background of fast neutrons and gammas) and irradiation and control rooms equipped by appropriate devices. Internationally-recognized software MacNCTPLAN is utilized for computational dosimetry and treatment planning. In the part of protocol the following parameters have been assessed: patient selection, BSH dosage, fractionation, starting dose, dose escalation steps. At the LVR-15, at horizontal channel, a prompt gamma ray analysis (PGRA) system has been developed and is operated for BNCT purposes. Some human blood samples were analyzed and compared with classical ICP method. During the process of licensing the experience was obtained, some notes are discussed in the paper. The first results were received for the study of biological effect of the LVR source for small animal model. (author)
Second order low-pass and high-pass filter designs using method of synthetic immitance elements
Pavel Brandstetter; Lukas Klein
2013-01-01
The paper briefly describes the basics of frequency filter design method using synthetic immittance elements with current conveyors. An introduction of the paper explains the advantages and also disadvantages of using this method. Other chapters briefly introduce a design process of simple second order low-pass and high-pass filter. A theory of current conveyors is discussed too, because they are the basic building blocs of proposed synthetic element and also active frequency filters. Finally...
Adaptive filter design based on the LMS algorithm for delay elimination in TCR/FC compensators.
Hooshmand, Rahmat Allah; Torabian Esfahani, Mahdi
2011-04-01
Thyristor controlled reactor with fixed capacitor (TCR/FC) compensators have the capability of compensating reactive power and improving power quality phenomena. Delay in the response of such compensators degrades their performance. In this paper, a new method based on adaptive filters (AF) is proposed in order to eliminate delay and increase the response of the TCR compensator. The algorithm designed for the adaptive filters is performed based on the least mean square (LMS) algorithm. In this design, instead of fixed capacitors, band-pass LC filters are used. To evaluate the filter, a TCR/FC compensator was used for nonlinear and time varying loads of electric arc furnaces (EAFs). These loads caused occurrence of power quality phenomena in the supplying system, such as voltage fluctuation and flicker, odd and even harmonics and unbalancing in voltage and current. The above design was implemented in a realistic system model of a steel complex. The simulation results show that applying the proposed control in the TCR/FC compensator efficiently eliminated delay in the response and improved the performance of the compensator in the power system. PMID:21193194
Modeling and Filter Design for Overvoltage Mitigation in a Motor Drive System with a Long Cable
Matsumura, Itaru; Akagi, Hirofumi
This paper presents an intensive discussion on modeling an adjustable-speed motor drive system consisting of a voltage-source PWM inverter and an induction motor that are connected by a three-phase symmetric, long cable with a grounding wire lead. Then, it describes a design procedure for a parallel-connected R-L filter in each phase that can mitigate the overvoltage appearing at the motor terminals. The model developed in this paper focuses on the inherent “ringing frequency” of the cable, where the ringing frequency is inversely proportional to cable length. When no filter is used, the so-called “impedance mismatch” causes the reflection of a voltage-traveling wave at both the inverter and the motor terminals. As a result, the impedance mismatch generates an overvoltage that may reach twice the inverter dc-link voltage at the motor terminals. The overvoltage may damage the motor-winding insulation, and may cause it to breakdown. Although an R-L filter installed on the ac side of the inverter can reduce the overvoltage, it would be difficult to design the filter effectively for long cables of different lengths. The effectiveness and validity of the simple design procedure described in this paper are confirmed on a 400-V, 15-kW experimental system with either a 100-m or 200-m-long cable.
Design and evaluation of a filter-based chairside amalgam separation system
Energy Technology Data Exchange (ETDEWEB)
Stone, Mark E. [Naval Institute for Dental and Biomedical Research, 310A B Street, Great Lakes, Illinois 60088 (United States)], E-mail: mark.stone@yahoo.com; Cohen, Mark E.; Berry, Denise L.; Ragain, James C. [Naval Institute for Dental and Biomedical Research, 310A B Street, Great Lakes, Illinois 60088 (United States)
2008-06-15
This study evaluated the ability of a chairside filtration system to remove particulate-based mercury (Hg) from dental-unit wastewater. Prototypes of the chairside filtration system were designed and fabricated using reusable filter chambers with disposable filter elements. The system was installed in five dental operatories utilizing filter elements with nominal pore sizes of 50{mu}m, 15{mu}m, 1{mu}m, 0.5{mu}m, or with no system installed (control). Daily chairside wastewater samples were collected on ten consecutive days from each room and brought to the laboratory for processing. After processing the wastewater samples, Hg concentrations were determined with cold vapor atomic absorption spectrometry (USEPA method 7470A). Filter systems were exchanged after ten samples were collected so that all five of the configurations were evaluated in each room (with assignment order balanced by a Latin Square). The numbers of surfaces of amalgam placed and removed per day were tracked in each room. In part two, new filter systems with the 0.5{mu}m filter elements were installed in the five dental operatories and vacuum levels at the high-velocity evacuation cannula tip were measured with a vacuum gauge. In part three of the study, the chairside filtration system utilizing 0.5{mu}m and 15{mu}m filter elements was evaluated utilizing the ISO 11143 testing protocol, a laboratory test of amalgam separator efficiency utilizing amalgam samples of known particle size distribution. Mean Hg per chair per day (no filter installed) was 1087.38mg (SD = 993.92mg). Mean Hg per chair per day for the 50{mu}m, 15{mu}m, 1{mu}m, 0.5{mu}m filter configurations was 79.13mg (SD = 71.40mg), 23.55mg (SD = 23.25mg), 17.68mg (SD = 17.35mg), and 4.25mg (SD = 6.35mg), respectively (n = 50 for all groups). Calculated removal efficiencies from the clinical samples were 92.7%, 97.8%, 98.4%, and 99.6%, respectively. ANCOVA on data from the four filter groups, with amalgam-surfaces-removed included as a
Design and evaluation of a filter-based chairside amalgam separation system
International Nuclear Information System (INIS)
This study evaluated the ability of a chairside filtration system to remove particulate-based mercury (Hg) from dental-unit wastewater. Prototypes of the chairside filtration system were designed and fabricated using reusable filter chambers with disposable filter elements. The system was installed in five dental operatories utilizing filter elements with nominal pore sizes of 50μm, 15μm, 1μm, 0.5μm, or with no system installed (control). Daily chairside wastewater samples were collected on ten consecutive days from each room and brought to the laboratory for processing. After processing the wastewater samples, Hg concentrations were determined with cold vapor atomic absorption spectrometry (USEPA method 7470A). Filter systems were exchanged after ten samples were collected so that all five of the configurations were evaluated in each room (with assignment order balanced by a Latin Square). The numbers of surfaces of amalgam placed and removed per day were tracked in each room. In part two, new filter systems with the 0.5μm filter elements were installed in the five dental operatories and vacuum levels at the high-velocity evacuation cannula tip were measured with a vacuum gauge. In part three of the study, the chairside filtration system utilizing 0.5μm and 15μm filter elements was evaluated utilizing the ISO 11143 testing protocol, a laboratory test of amalgam separator efficiency utilizing amalgam samples of known particle size distribution. Mean Hg per chair per day (no filter installed) was 1087.38mg (SD = 993.92mg). Mean Hg per chair per day for the 50μm, 15μm, 1μm, 0.5μm filter configurations was 79.13mg (SD = 71.40mg), 23.55mg (SD = 23.25mg), 17.68mg (SD = 17.35mg), and 4.25mg (SD = 6.35mg), respectively (n = 50 for all groups). Calculated removal efficiencies from the clinical samples were 92.7%, 97.8%, 98.4%, and 99.6%, respectively. ANCOVA on data from the four filter groups, with amalgam-surfaces-removed included as a significant covariate
Development of the high power multi-stage type circulator for BNCT system
International Nuclear Information System (INIS)
The process for BNCT begins with a pharmaceutical agent that carries a neutron capture agent containing 10B (Boron 10) selectively into tumor cells. Thermal or epi-thermal neutrons then interact with the 10B and produce α and 7Li-particles. So far, BNCT have been provided only by nuclear reactors, because a neutron intensity of 1x109n/cm2/s, with energies between 0.5-eV and 10-keV is required. To realize BNCT using accelerator technologies, one of the big issuer is the high duty rf system, which will be used for 324 MHz, 1.2 MW peak klystron, 1 msec of an rf pulse width and a 200 Hz of cycle. A high power circulator is the most critical component among the waveguide system. It was redesigned from a linear accelerator of J-PARC to meet the 20% of a duty factor using a high saturation magnetization 4piMs has high curie temperature. Also, it was used thin ferrite layer to reduce the temperature rise and to reduce the temperature sensitivity. This paper reports the design work, the manufacture and a low power measurement. (author)
A neural network-based optimal spatial filter design method for motor imagery classification.
Yuksel, Ayhan; Olmez, Tamer
2015-01-01
In this study, a novel spatial filter design method is introduced. Spatial filtering is an important processing step for feature extraction in motor imagery-based brain-computer interfaces. This paper introduces a new motor imagery signal classification method combined with spatial filter optimization. We simultaneously train the spatial filter and the classifier using a neural network approach. The proposed spatial filter network (SFN) is composed of two layers: a spatial filtering layer and a classifier layer. These two layers are linked to each other with non-linear mapping functions. The proposed method addresses two shortcomings of the common spatial patterns (CSP) algorithm. First, CSP aims to maximize the between-classes variance while ignoring the minimization of within-classes variances. Consequently, the features obtained using the CSP method may have large within-classes variances. Second, the maximizing optimization function of CSP increases the classification accuracy indirectly because an independent classifier is used after the CSP method. With SFN, we aimed to maximize the between-classes variance while minimizing within-classes variances and simultaneously optimizing the spatial filter and the classifier. To classify motor imagery EEG signals, we modified the well-known feed-forward structure and derived forward and backward equations that correspond to the proposed structure. We tested our algorithm on simple toy data. Then, we compared the SFN with conventional CSP and its multi-class version, called one-versus-rest CSP, on two data sets from BCI competition III. The evaluation results demonstrate that SFN is a good alternative for classifying motor imagery EEG signals with increased classification accuracy. PMID:25933101
Optimal Gain Kalman Filter Design With Dc Motor Speed Controlled Parameters
Khalaf SalloumGaeid
2013-01-01
The aim of this work, to design an appropriate Kalman filter(KF) with optimal gain as well as a two degree of freedom compensator for the DC motor, verify the stability of the proposed algorithm and the noise sensitivity are carried out. The design of the present algorithm is to combine both 2DOFPID controller with the optimal gain obtained by designing a (KF) to obtain better performance. The sensor noise covariance has been precisely chosen to design of the (KF) through state space model of...
Band-Pass and OH-Suppression Filters for the E-ELT - Design and Prototyping
Guenster, S; Davies, R
2011-01-01
Optical filters are used for a variety of purposes at astronomical telescopes. In the near infrared region, from 0.8 to 2.5 um, bandpass and edge filters are used to separate the different astronomical channels, such as the J, H, and K bands. However, in the same wavelength range light emission generated in the earth's atmosphere is superimposed on the stellar radiation. Therefore, ground based astronomical instruments measure, in addition to the stellar light, also unwanted contributions from the earth's atmosphere. The characteristic lines of this OH emission are extremely narrow and distributed over the complete NIR spectral range. The sensitivity of future telescopes, like the European Extreme Large Telescope (E-ELT) which is currently being designed by ESO, can be dramatically improved if the atmospheric emission lines are effectively suppressed while the stellar radiation is efficiently transferred to the detector systems. For this task, new types of optical filters have to be developed. In this framewo...
Design and Development of a High Efficiency CarbonGranular Bed Filter in Industrial Scale
Institute of Scientific and Technical Information of China (English)
张济宇; 旷戈; 林诚
2004-01-01
The new dust removal technical route using the carbon-granular bed filter, packed of carbon particles with appropriate grade derive from an online-process vibration sieve, to replace the traditional baggy filter had been developed successfully for capturing the micro-carbon dusts produced from pulverization of petroleum coke,and the green close loop of carbon materials is thus completed in the combined pulverizing and classifying system and pulverized carbon dust removal process. The high dust removal efficiency greater than 99%, low outlet dust concentration less than 100 mg-m-S, low pressure drop through dust filtration chamber less than 980 Pa, simple and easy design, and flexible and stable operation were achieved also with the carbon-granular bed filter in both bench and industrial scale operations.
Directory of Open Access Journals (Sweden)
Anass Benjebbour
2008-02-01
Full Text Available In the future, there will be a growing need for more flexible but efficient utilization of radio resources. Increased flexibility in radio transmission, however, yields a higher likelihood of interference owing to limited coordination among users. In this paper, we address the problem of flexible spectrum sharing where a wideband single carrier modulated signal is spectrally overlapped by unknown narrowband interference (NBI and where a cyclic Wiener filter is utilized for nonparametric NBI suppression at the receiver. The pulse shape design for the wideband signal is investigated to improve the NBI suppression capability of cyclic Wiener filtering. Specifically, two pulse shaping schemes, which outperform existing raised cosine pulse shaping schemes even for the same amount of excess bandwidth, are proposed. Based on computer simulation, the interference suppression capability of cyclic Wiener filtering is evaluated for both the proposed and existing pulse shaping schemes under several interference conditions and over both AWGN and Rayleigh fading channels.
Elaborate analysis and design of filter-bank-based sensing for wideband cognitive radios
Maliatsos, Konstantinos; Adamis, Athanasios; Kanatas, Athanasios G.
2014-12-01
The successful operation of a cognitive radio system strongly depends on its ability to sense the radio environment. With the use of spectrum sensing algorithms, the cognitive radio is required to detect co-existing licensed primary transmissions and to protect them from interference. This paper focuses on filter-bank-based sensing and provides a solid theoretical background for the design of these detectors. Optimum detectors based on the Neyman-Pearson theorem are developed for uniform discrete Fourier transform (DFT) and modified DFT filter banks with root-Nyquist filters. The proposed sensing framework does not require frequency alignment between the filter bank of the sensor and the primary signal. Each wideband primary channel is spanned and monitored by several sensor subchannels that analyse it in narrowband signals. Filter-bank-based sensing is proved to be robust and efficient under coloured noise. Moreover, the performance of the weighted energy detector as a sensing technique is evaluated. Finally, based on the Locally Most Powerful and the Generalized Likelihood Ratio test, real-world sensing algorithms that do not require a priori knowledge are proposed and tested.
Optimal matched filter design for ultrasonic NDE of coarse grain materials
Li, Minghui; Hayward, Gordon
2016-02-01
Coarse grain materials are widely used in a variety of key industrial sectors like energy, oil and gas, and aerospace due to their attractive properties. However, when these materials are inspected using ultrasound, the flaw echoes are usually contaminated by high-level, correlated grain noise originating from the material microstructures, which is time-invariant and demonstrates similar spectral characteristics as flaw signals. As a result, the reliable inspection of such materials is highly challenging. In this paper, we present a method for reliable ultrasonic non-destructive evaluation (NDE) of coarse grain materials using matched filters, where the filter is designed to approximate and match the unknown defect echoes, and a particle swarm optimization (PSO) paradigm is employed to search for the optimal parameters in the filter response with an objective to maximise the output signal-to-noise ratio (SNR). Experiments with a 128-element 5MHz transducer array on mild steel and INCONEL Alloy 617 samples are conducted, and the results confirm that the SNR of the images is improved by about 10-20 dB if the optimized matched filter is applied to all the A-scan waveforms prior to image formation. Furthermore, the matched filter can be implemented in real-time with low extra computational cost.
Design of Substrate Integrated Waveguide Pass Filter at [33-75] GHz Band
Directory of Open Access Journals (Sweden)
Ahmed Rhbanou
2014-12-01
Full Text Available This article presented the design of two filters SIW (Substrate Integrated Waveguide in two different bands. Their conceptions were made by two different topologies. The first SIW filter with circular inductive post in the band [33-50] GHz on an RT / Duroid 5880 substrate permittivity 2.2, the simulated results of this filter have shown that the insertion loss lower than -0.4 dB within 3.5% bandwidth around 41.7 GHz and the return loss is better than -15 dB between 41.1 GHz and 42.4 GHz. The second SIW filter with iris in the band [50-75] GHz on an NY9217 (IM substrate permittivity 2.17, the simulated results of this filter have shown that the insertion loss lower than -0.35 dB within 19% bandwidth around 62 GHz and the return loss is better than -15 dB between 60 GHz and 66.3 GHz. The compatibility with planar circuits is provided via a specific microstrip transition (microstrip tapered transitions.
Kilbourne, C. A.; Adams, J. S.; Arsenovic, P.; Ayers, T.; Chiao, M. P.; DiPirro, M. J.; Eckart, M. E.; Fujimoto, R.; Kazeva, J. D.; Kelley, R. L.; Kripps, K. L.; Lairson, B.; Leutenegger, M. A.; Lopez, H.; McCammon, D.; McGuinness, D. S.; Mitsuda, K.; Moseley, S. J.; Porter, F. S.; Schweiss, A. N.; Takei, Y.; Thorpe, R. S.; Watanabe, T.; Yamasaki, N. Y.; Yoshida, S.
2016-01-01
The calorimeter array of the JAXA Astro-H (renamed Hitomi) Soft X-ray Spectrometer (SXS) was designed to provide unprecedented spectral resolution of spatially extended cosmic x-ray sources and of all cosmic x-ray sources in the Fe-K band around 6 keV. The properties that make the SXS a powerful x-ray spectrometer also make it sensitive to the entire electromagnetic band. If characterized as a bolometer, it would have a noise equivalent power (NEP) of < 4x10(exp -18) W/(Hz)0.5. Thus it was imperative to shield the detector from thermal radiation from the instrument and optical and UV photons from the sky. Additionally, it was necessary to shield the coldest stages of the instrument from the thermal radiation emanating from the warmer stages. These needs are addressed by a series of five thin-film radiation blocking filters that block long-wavelength radiation while minimizing x-ray attenuation. The SXS aperture assembly is a system of barriers, baffles, filter carriers, and filter mounts that supports the filters and inhibits their potential contamination. The three warmer filters also were equipped with thermometers and heaters for decontamination.
Application of Implicit Space Mapping in the Design of Hammerhead Filter in Millimeter-Wave Band
Directory of Open Access Journals (Sweden)
Fuqun Zhong
2012-03-01
Full Text Available In this study, we present advances in microwave and millimeter-wave device modeling exploiting the Space Mapping (SM technology. New SM-based modeling techniques are used that are easy to implement entirely in the Agilent ADS framework. The implicit space mapping algorithm is applied to the design of hammerhead filter in millimeter-wave band. The validity of this method is confirmed by comparison with fullwave EM simulation result and measured data. Based on the proposed method, a filter was designed and fabricated on a substrate with thickness of 0.254 mm and dielectric constant of 2.2. The experimental results show good agreement with simulated results. It is proved that the accuracy can be achieved using the implicit space mapping algorithm, and the design efficiency can be greatly improved.
A controller design method for 3 phase 4 wire grid connected VSI with LCL filter
Indian Academy of Sciences (India)
Anirban Ghoshal; Vinod John
2015-08-01
Closed loop control of a grid connected VSI requires line current control and dc bus voltage control. The closed loop system comprising PR current controller and grid connected VSI with LCL filter is a higher order system. Closed loop control gain expressions are therefore difficult to obtain directly for such systems. In this work a simplified approach has been adopted to find current and voltage controller gain expressions for a 3 phase 4 wire grid connected VSI with LCL filter. The closed loop system considered here utilises PR current controller in natural reference frame and PI controller for dc bus voltage control. Asymptotic frequency response plot and gain bandwidth requirements of the system have been used for current control and voltage controller design. A simplified lower order model, derived for closed loop current control, is used for the dc bus voltage controller design. The adopted design method has been verified through experiments by comparison of the time domain response.
Measurement of thermal neutron flux for BNCT in JRR-2
International Nuclear Information System (INIS)
For Boron Neutron Capture Therapy (BNCT) on brain tumor, a medical irradiation facility has been installed in the Japan Research Reactor No.2 (JRR-2) in Japan Atomic Energy Research Institute (JAERI). The first BNCT using by this facility was performed in August 1990. Since then, irradiations for 15 BNCT were performed until March 1993 in JRR-2. Two kinds of devices has been equipped for the measurement of thermal neutron flux at the diseased part of patients. The one is for the measurement of activation of thin gold wire using β-γ coincidence equipment, and the other is for the simultaneous monitoring of neutron fluxes during BNCT using silicon semiconductor detectors. The measurements using these devices are reported in this paper. (author)
Present status of BNCT at Kyoto University Research Reactor Institute
International Nuclear Information System (INIS)
At Kyoto University Research Reactor Institute, we have two facilities for BNCT such as a reactor-based and an accelerator-based neutron source. In this article, we will present the characteristics overview of both facilities. (author)
Design Optimization of Vena Cava Filters: An application to dual filtration devices
Energy Technology Data Exchange (ETDEWEB)
Singer, M A; Wang, S L; Diachin, D P
2009-12-03
Pulmonary embolism (PE) is a significant medical problem that results in over 300,000 fatalities per year. A common preventative treatment for PE is the insertion of a metallic filter into the inferior vena cava that traps thrombi before they reach the lungs. The goal of this work is to use methods of mathematical modeling and design optimization to determine the configuration of trapped thrombi that minimizes the hemodynamic disruption. The resulting configuration has implications for constructing an optimally designed vena cava filter. Computational fluid dynamics is coupled with a nonlinear optimization algorithm to determine the optimal configuration of trapped model thrombus in the inferior vena cava. The location and shape of the thrombus are parameterized, and an objective function, based on wall shear stresses, determines the worthiness of a given configuration. The methods are fully automated and demonstrate the capabilities of a design optimization framework that is broadly applicable. Changes to thrombus location and shape alter the velocity contours and wall shear stress profiles significantly. For vena cava filters that trap two thrombi simultaneously, the undesirable flow dynamics past one thrombus can be mitigated by leveraging the flow past the other thrombus. Streamlining the shape of thrombus trapped along the cava wall reduces the disruption to the flow, but increases the area exposed to abnormal wall shear stress. Computer-based design optimization is a useful tool for developing vena cava filters. Characterizing and parameterizing the design requirements and constraints is essential for constructing devices that address clinical complications. In addition, formulating a well-defined objective function that quantifies clinical risks and benefits is needed for designing devices that are clinically viable.
Houts, R. C.; Burlage, D. W.
1972-01-01
A time domain technique is developed to design finite-duration impulse response digital filters using linear programming. Two related applications of this technique in data transmission systems are considered. The first is the design of pulse shaping digital filters to generate or detect signaling waveforms transmitted over bandlimited channels that are assumed to have ideal low pass or bandpass characteristics. The second is the design of digital filters to be used as preset equalizers in cascade with channels that have known impulse response characteristics. Example designs are presented which illustrate that excellent waveforms can be generated with frequency-sampling filters and the ease with which digital transversal filters can be designed for preset equalization.
Containment filter system for WWER type reactors in case of beyond design basis accident
International Nuclear Information System (INIS)
The papers presents a scheme of a filter design for WWER type reactors for the releasing of the pressurized vapour-air mixture from the containment and filtering of the radioactive products (fine particles and aerosols) in case of a beyond design basis accident,. The first main component of the filter is a bubbling type mixer where a condensations of the vapour component takes part and the non-condensed (air ) component has been filtered. Experiment have been performed for various values of the weight ratio between the steam and air components, corresponding to the conditions in case of a severe accident with a leakage in the containment. The tested bubbling mixer has 80 cm2 effective flow section. The results show a full vapour component condensation in case of an effective phase mixing. Analyses, made for the WWER-1000 reactors of the Kozloduy NPP, show that the expected vapour consumption can be assured by using of 1-3 parallel units. The second element of this unit - separator - consists of two elements - a demister, which presents a patch of metal wool separated by a metal net with a large effective section, and a droplets turbo-separator. The combination of a demister and turbo-separator can ensure up to 99.5% cleaning. The turbo-separator is tested is introduced in production with very good results
Photonic-Crystal Band-pass Resonant Filters Design Using the Two-dimensional FDTD Method
Directory of Open Access Journals (Sweden)
Hadjira Badaoui
2011-05-01
Full Text Available Recently, band-pass photonic crystal filters have attracted great attention due to their important applications in the fields of optical interconnection network and ultrahigh speed information processing. In this paper we propose the design of a new type of photonic crystal band-pass resonant filters realized in one-missing-row waveguide by decreasing proper defects along the waveguide with broadband acceptable bandwidth. Two types of photonic crystal band-pass filters are utilized and optimized using the Two-dimensional finite-difference time-domain (FDTD technique. The first one is based on the Fabry-Perot cavities and in the second one a cavity is introduced in the middle by omitting two neighboring air holes in waveguide. Numerical results show that a band [1.47 and#956;m-1.57 and#956;m] around 1.55um is transmitted with a maximum transmission of about 68% and as a result wide band-pass filters are designed.
ATLID receiving spatial and spectral filtering units: design and associated performances
Vaché, Maxime; de Saint Seine, Diego; Leblay, Pierrick; Hélière, Arnaud; Pereira Do Carmo, João.; Berlioz, Philippe; Archer, Julien
2015-09-01
ATLID (ATmospheric LIDar) is one of the four key instruments of EarthCARE (Earth Clouds, Aerosols and Radiations Explorer) satellite. It is a program of and funded by the European Space Agency and under prime contractorship of Airbus Defence and Space. ATLID is dedicated to the understanding of aerosols and clouds contribution to earth climate. It is an atmospheric LIDAR that measures the emitted 354.8nm ultraviolet laser which is backscattered by the atmosphere. The molecules and the particles have different optical signatures and can consequently be distinguished thanks to polarization analyses and spectral filtering of the backscattered signal. The following optical units of ATLID receiver chain directly contribute to this function : after ATLID afocal telescope, the CAS-OA, the Optical Assembly of the Co Alignment Sensor, samples and images the beam on the CAS sensor in order to optimize the alignment of transmitting and receiving telescopes. The beam goes through the BF sub-assemblies, the Blocking Filter which has two filtering functions: (1) spatial with the ERO-BF, which is a Kepler afocal spatial filtering module that defines the instrument field of view and blocks the background and straylight out of the useful field of view; (2) spectral with the ERO-EFO, the Entrance Filtering Optic, which is mainly composed of a very narrow bandpass filter with a high rejection factor. This filter rejects the background from the useful signal and contributes to increase the signal-to-noise ratio. The EFO also allows an on-ground adjustment of the orientation of the linear polarization of the input beam. After filtering and polarization adjustment, the beam is injected in several optical fibers and transported to the instrument detectors. This last transport function is done by the FCA, the Fiber Coupler Assembly. This paper presents the flight models of the previously described units, details the opto-mechanical design, and reviews the main achieved performances with a
A case of astrocytoma, 19 year history after BNCT
International Nuclear Information System (INIS)
A 39-year-old man had received Boron Neutron Capture Therapy (BNCT) in 1987 for a Grade II Astrocytoma. He gradually exacerbated and received a second operation in 1994. The mass taken in the second operation is almost competent with radiation necrosis. Following that, he shows no signs of recurrence. Currently, he has returned to full time employment in physical labor. This case suggests effectiveness of BNCT for rather low-grade astrocytomas. (author)
Second Order Low-Pass and High-Pass Filter Designs Using Method of Synthetic Immitance Elements
Directory of Open Access Journals (Sweden)
Pavel Brandstetter
2013-01-01
Full Text Available The paper briefly describes the basics of frequency filter design method using synthetic immittance elements with current conveyors. An introduction of the paper explains the advantages and also disadvantages of using this method. Other chapters briefly introduce a design process of simple second order low-pass and high-pass filter. A theory of current conveyors is discussed too, because they are the basic building blocs of proposed synthetic element and also active frequency filters. Finally, the particular solutions of low-pass and high-pass filters are given and verified by OrCAD PSpice simulations.
Embedded FIR filter design for real-time refocusing using a standard plenoptic video camera
Hahne, Christopher; Aggoun, Amar
2014-03-01
A novel and low-cost embedded hardware architecture for real-time refocusing based on a standard plenoptic camera is presented in this study. The proposed layout design synthesizes refocusing slices directly from micro images by omitting the process for the commonly used sub-aperture extraction. Therefore, intellectual property cores, containing switch controlled Finite Impulse Response (FIR) filters, are developed and applied to the Field Programmable Gate Array (FPGA) XC6SLX45 from Xilinx. Enabling the hardware design to work economically, the FIR filters are composed of stored product as well as upsampling and interpolation techniques in order to achieve an ideal relation between image resolution, delay time, power consumption and the demand of logic gates. The video output is transmitted via High-Definition Multimedia Interface (HDMI) with a resolution of 720p at a frame rate of 60 fps conforming to the HD ready standard. Examples of the synthesized refocusing slices are presented.
A Study on Sub-pixel Interpolation Filtering Algorithm and Hardware Structural Design Aiming at HEVC
Directory of Open Access Journals (Sweden)
Wang Gang
2013-07-01
Full Text Available Aiming at the new-generation video compression standard being formulated—HEVC, a kind of sub-pixel interpolation filtering algorithm is proposed (luminance: 1/4 precision, chrominance: 1/8 precision. Based on the algorithm, a hardware design with pipeline structure and high degree of parallelism is put forward. The hardware overhead is reduced by multiplex Wiener filter and the reduction of the size of register array. And the interpolation order of vertical priority is adopted to reduce the reading bandwidth of the storage. It is indicated from the performance analysis that this interpolation structure possesses better performance and smaller hardware overhead. This design also takes full consideration of the balance between speed and area, meeting the requirements of processing standard definition and high definition video image.
Directory of Open Access Journals (Sweden)
Harizi Hanen
2012-01-01
Full Text Available Problem statement: The expansion of RF, microwave and millimeter devices has revolutionized todayâs ommunication and sensor systems. Low-cost, high-performance and mass producible millimeter wave technologies are vital for commercial broadband systems. Challenging issues are commonly faced in the design of low-loss integrated circuits for example high-Q band pass filter, which the planar technique is fundamentally limited in performance. Approach: In this study, we present a design of a nonradiative dielectric waveguide band pass filter based on hybrid architecture of micro strip line and non-radiative dielectric waveguide. Results: The simulation with High Frequency Structure Simulator (HFSS three dimensional analyses is presented. Conclusion: The non radiative dielectric resolves most of the drawbacks of dielectric waveguide in connection with the radiation loss."
DeJarnette, Drew; Brekke, Nick; Tunkara, Ebrima; Hari, Parameswar; Roberts, Kenneth; Otanicar, Todd
2015-09-01
A nanoparticle fluid filter used with concentrating hybrid solar/thermal collector design is presented. Nanoparticle fluid filters could be situated on any given concentrating system with appropriate customized engineering. This work shows the design in the context of a trough concentration system. Geometric design and physical placement in the optical path was modeled using SolTrace. It was found that a design can be made that blocks 0% of the traced rays. The nanoparticle fluid filter is tunable for different concentrating systems using various PV cells or operating at varying temperatures.
DEFF Research Database (Denmark)
Kouchaki, Alireza; Nymand, Morten
2016-01-01
This paper presents LCL filter design method for three-phase two-level power factor correction (PFC) using line impedance stabilization network (LISN). A straightforward LCL filter design along with variation in grid impedance is not simply achievable and inevitably lead to an iterative solution...... for filter. By introducing of fast power switches for PFC applications such as silicon-carbide, major current harmonics around the switching frequency drops in the region that LISN can actively provide well-defined impedance for measuring the harmonics (i.e. 9 kHz- 30MHz). Therefore, LISN can be replaced...... with unknown grid impedance at high frequency, simplify the model of the filter, and provide repetitive measurements. In this paper, all the filter parameters are derived with analyzing the behavior of the converter at high frequency with presence of LISN impedance. The minimum required filter capacitor...
International Nuclear Information System (INIS)
The rotational Raman lidar is an effective remote sensing tool to measure the temperature of the lower atmosphere where abundant aerosol particles exist; however, it is very difficult to structure the Raman spectroscopic filter system using current technology. In view of their excellent optical properties, several photonic crystals are selected to structure a novel Raman spectroscopic filter. To obtain the desired design parameters of the filter, the genetic algorithm, as a global optimum searching algorithm, is employed to optimize the parameters of the photonic crystal filter. Some numerical simulations are carried out and the results show that it is feasible to use the genetic algorithm to design the filter parameters, and the novel spectroscopic filter system can effectively draw the required rotational Raman signals at the central wavelengths of 530.3 nm and 529 nm, respectively, for atmospheric temperature retrieval and simultaneously block Mie- and Rayleigh-scattering signals at 532 nm with a rejection rate of seven orders of magnitude. (paper)
Characterisation of the TAPIRO BNCT thermal facility
International Nuclear Information System (INIS)
Dosimetry and spectrometry measurements have been carried out in the thermal column of the research fast reactor RSV-TAPIRO (ENEA-Casaccia, Rome) in order to investigate its suitability for irradiation of cells or mice, with a view to research in the interests of boron neutron capture therapy (BNCT). The thermal column consists of a graphite moderator (40 cm thick) containing a lead shield (13 cm thick) in order to shield reactor background. The irradiation volume, inside this structure, has cubic shape (18 x 18 x 18 cm3). Besides measurements of fluence and dose rates in air or in phantom performed with thermoluminescence dosemeters (TLDs) and using the activation technique, dose and fluence profiles have been generated using a method based on gel dosemeters analysed with optical imaging. To check the consistency of the results, spectrometry measurements in the same irradiation volume have been performed by means of bubble detectors. (authors)
Optimizing The Gate Level Area In Digit Serial FIR Filter Design With An MCM Blocks
Directory of Open Access Journals (Sweden)
Bayikati Yagneswar
2014-06-01
Full Text Available The last two decades have seen many efficient algorithms and architectures for the design of low -complexity bit-parallel Multiple Constant Multiplications (MCM operation, which dominates the complexity of Digital Signal Processing (DSP systems. On the other hand, digit-serial architectures offer alternative low -complexity designs, since digit-serial operators occupy less area and are independent of the data wordlength. This paper introduces the problem of designing a digit-serial MCM operation with minimal area at gate-level and presents the exact formalization of the area optimization problem as a 0-1 Integer Linear Programming (ILP problem and introduces high level synthesis algorithms, design architectures, and a computer aided design tool. Results and Discussion show the efficiency of the proposed optimization algorithms and of the digit-serial MCM architectures in the design of digit serial MCM operations and finite impulse response filters.
An Observer-Based Adaptive Iterative Learning Control Using Filtered-FNN Design for Robotic Systems
Ying-Chung Wang; Chiang-Ju Chien
2014-01-01
An observer-based adaptive iterative learning control using a filtered fuzzy neural network is proposed for repetitive tracking control of robotic systems. A state tracking error observer is introduced to design the iterative learning controller using only the measurement of joint position. We first derive an observation error model based on the state tracking error observer. Then, by introducing some auxiliary signals, the iterative learning controller is proposed based on the use of an aver...
Two-Dimensional IIR Filter Design Using Simulated Annealing Based Particle Swarm Optimization
Supriya Dhabal; Palaniandavar Venkateswaran
2014-01-01
We present a novel hybrid algorithm based on particle swarm optimization (PSO) and simulated annealing (SA) for the design of two-dimensional recursive digital filters. The proposed method, known as SA-PSO, integrates the global search ability of PSO with the local search ability of SA and offsets the weakness of each other. The acceptance criterion of Metropolis is included in the basic algorithm of PSO to increase the swarm’s diversity by accepting sometimes weaker solutions also. The exper...
A LTE UPCUL architecture design combining Multi-Blackboards and Pipes & Filters architectures
Jiang Axelsson, Bohui
2015-01-01
Context. The single blackboard architecture is widely used in the LTE application area. Despite its several benefits, this architecture limits synchronization possibilities of the developed systems and increases the signal operational latency. As a result the DSP (Digital Signal Processing) utilization is suboptimal. Objectives. In this thesis, we design a new architecture, which combines concepts of Multi-Blackboards and Pipes & Filters architectures, as a replacement for the current si...
Thermal Filters for the ATHENA X-IFU: Ongoing Activities Toward the Conceptual Design
Barbera, Marco; Argan, A.; Bozzo, E.; Branduardi-Raymont, G.; Ciaravella, A.; Collura, A.; Cuttaia, F.; Gatti, F.; Jimenez Escobar, A.; Lo Cicero, U.; Lotti, S.; Macculi, C.; Mineo, T.; Nuzzo, F.; Paltani, S.; Parodi, G.; Piro, L.; Rauw, G.; Sciortino, L.; Sciortino, S.; Villa, F.
2016-02-01
ATHENA is the L2 mission selected by ESA to pursue the science theme "Hot and Energetic Universe." One of the two focal plane instruments is the X-ray Integral Field Unit, an array of TES microcalorimeters operated at T electromagnetic interferences on TES sensors and SQUID electronics, and to protect the detector from contamination. This paper reviews the ongoing activities driving the design of the X-IFU thermal filters.
Clark, Peter A.; Pinedo, Catalina Arango; Fadus, Matthew; Capuzzi, Stephen
2012-01-01
Summary The need for clean water has risen exponentially over the globe. Millions of people are affected daily by a lack of clean water, especially women and children, as much of their day is dedicated to collecting water. The global water crisis not only has severe medical implications, but social, political, and economic consequences as well. The Institute of Catholic Bioethics at Saint Joseph’s University has recognized this, and has designed a slow-sand water filter that is accessible, co...
Design of Microwave Front-End Narrowband Filter and Limiter Components
Cross, Lee W.
variation during limiting. Limiter functionality has minimal impact on filter size, weight, performance, and cost. The third proposed device demonstrates a large-area, light-weight plasma device that interacts with propagating X-band (8-12 GHz) microwave energy. The structure acts as a switchable EM aperture that can be integrated into a radome structure that shields enclosed antenna(s) from incident energy. Active elements are plasma-shells that are electrically excited by frequency selective surfaces (FSS) that are transparent to the frequency band of interest. The result is equivalent to large-area free-space plasma confined in a discrete layer. A novel structure was designed with the aid of full-wave simulation and was fabricated as a 76.2 mm square array. Transmission performance was tested across different drive voltages and incidence angles. Switchable attenuation of 7 dB was measured across the passband when driven with 1400 Vpp at 1 MHz. Plasma electron density was estimated to be 3.6 x 10 12 cm-3 from theory and full-wave simulation. The proposed structure has potential for use on mobile platforms.
International Nuclear Information System (INIS)
In a prototype filter offgas cleaning system for reprocessing plants (PASSAT) built at the Karlsruhe Nuclear Research Center a fullscale filter cell with remotely handled filters for aerosol and iodine removal and the corresponding remote handling systems for exchange, bagging out, packaging and disposal of spent filter elements has been installed and run in trial operation since July 1978. The filters and the replacement techniques have been tested for the past two years or so and so far have always worked satisfactory over the test period involving some 150 replacement events. Neither wear nor corrosion phenomena were found in the filter housings and the replacement systems. The seals and clamping devices were selected so that during operation the prescribed leak rates of -3 Torr l/s were always maintained on the filter lid, the seat of the filter element and the cell lock. The total clamping loads for the filter element and the filter lid amount to approx. 20 kN. The force necessary to separate the filter element from the filter housing is approx. 3.5 kN. No ruptures of seals or gaskets were to be detected. The design of the filters and of the handling systems has been found satisfactorily in the cold test operation so far and can be recommended for use in nuclear facilities. In all experiments conducted until now PASSAT has worked without any failure. All operating data required in the specifications were met in the test period. The maximum pressure loss in the system with loaded filter elements amounts to some 3000 mm of water. After operation with iodine and NO/sub x/, plant components exposed to 100% relative humidity and condensate showed corrosion
International Nuclear Information System (INIS)
The authors have reviewed the literature on the performance of high efficiency particulate air (HEPA) filters under normal and abnormal conditions to establish criteria for calculating the efficiency of HEPA filters in a DOE nonreactor nuclear facility during and after a Design Basis Accident (DBA). This study is only applicable to the standard deep-pleated HEPA filter with aluminum separators as specified in ASME N509. The literature review included the performance of new filters and parameters that may cause deterioration in the filter performance such as filter age, radiation, corrosive chemicals, seismic and rough handling, high temperature, moisture, particle clogging, high air flow and pressure pulses. The deterioration of the filter efficiency depends on the exposure parameters; in severe exposure conditions the filter will be structurally damaged and have a residual efficiency of 0%. Despite the many studies on HEPA filter performance under adverse conditions, there are large gaps and limitations in the data that introduce significant error in the estimates of HEPA filter efficiencies under DBA conditions. Because of this limitation, conservative values of filter efficiency were chosen when there was insufficient data
Influence of BNCT radiations on the blood-brain barrier in terms of boron-10 uptake
International Nuclear Information System (INIS)
A key issue is to determine whether fractionated BNCT is a feasible proposition. This issue has been reviewed by Dorn et al, who call for further experimental investigation of BNCT induced changes in the blood brain barrier and investigated by Hatanaka et al. In order to investigate the effect on BNCT, the authors measured 10B concentration and water content in the normal brain which has been subjected to BNCT regimen
Challenges to the design of containment filtered venting systems at NPP
International Nuclear Information System (INIS)
Severe accidents (SA) may result in pressure and temperature increase leading to containment failure and uncontrolled release of radioactive products to the environment. Containment over-pressurization can be prevented by the operation of a Containment Filter Venting System (CFVS) intended to actuate within the specific SA conditions. However, the particular design solution and especially the sizing of appropriate Containment Filter Venting System require precise information regarding the accident progression and parameters. Such information may be obtained only by detailed assessment of each phase of the severe accident considering the specific reactor technology. Therefore, a study was performed in order to evaluate the most challenging conditions and the most suitable solution for implementation of a system for filtered venting of the containment taking into account the uncertain nature of the accidents and the limitations of the mathematical simulations. The current paper presents the main results from the above mentioned study on the influence of the severe accident conditions, including the specific containment environment effects, to the design and sizing of Containment Filter Venting System. The study includes the selection of a bounding case and the initial conditions for simulation of a severe accident scenario which is expected to pose the most stringent requirements to the CFVS. Evaluation of the Molten Core Concrete Interaction (MCCI) parameters and analysis of system performance during the severe accident progression is furthermore performed. The main parameters of the accident scenario under evaluation are the timing of the vessel failure and the containment design limit pressure achievement, hydrogen production during the accident and its influence on the system operation. The accuracy of predictions of the severe accident parameters (containment pressure and temperature, fission product mass concentration at different stages of accident, modelling
Computational dosimetry of a simulated combined standard X-Rays and BNCT treatment
Energy Technology Data Exchange (ETDEWEB)
Casal, M.R., E-mail: mcasal@cnea.gov.ar [Instituto de Oncologia ' Angel H. Roffo' , Universidad de Buenos Aires, Av. San Martin 5481, Bs.As. (Argentina)] [Comision Nacional de Energia Atomica, Av. General Paz 1499, San Martin, Buenos Aires (Argentina); Herrera, M.S., E-mail: mariettaherrera@gmail.com [Comision Nacional de Energia Atomica, Av. General Paz 1499, San Martin, Buenos Aires (Argentina)] [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) Av. Rivadavia 191, Buenos Aires (Argentina)] [Escuela de Ciencia y Tecnologia, Universidad de General San Martin, 25 de Mayo and M. de Irigoyen, San Martin (Argentina); Gonzalez, S.J., E-mail: srgonzal@cnea.gov.ar [Comision Nacional de Energia Atomica, Av. General Paz 1499, San Martin, Buenos Aires (Argentina)] [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) Av. Rivadavia 191, Buenos Aires (Argentina)
2011-12-15
There has been increasing interest in combining Boron Neutron Capture Therapy (BNCT) with standard radiotherapy, either concomitantly or as a BNCT treatment of a recurrent tumor that was previously irradiated with a medical electron linear accelerator (LINAC). In this work we report the simulated dosimetry of treatments combining X-rays and BNCT
Radiation field characterization of a BNCT research facility using Monte Carlo method - code MCNP-4B
International Nuclear Information System (INIS)
Boron Neutron Capture Therapy - BNCT - is a selective cancer treatment and arises as an alternative therapy to treat cancer when usual techniques - surgery, chemotherapy or radiotherapy - show no satisfactory results. The main proposal of this work is to project a facility to BNCT studies. This facility relies on the use of an Am Be neutron source and on a set of moderators, filters and shielding which will provide the best neutron/gamma beam characteristic for these Becton studies, i.e., high intensity thermal and/or epithermal neutron fluxes and with the minimum feasible gamma rays and fast neutrons contaminants. A computational model of the experiment was used to obtain the radiation field in the sample irradiation position. The calculations have been performed with the MCNP 4B Monte Carlo Code and the results obtained can be regarded as satisfactory, i.e., a thermal neutron fluencyNT = 1,35x108 n/cm , a fast neutron dose of 5,86x10-10 Gy/NT and a gamma ray dose of 8,30x10-14 Gy/NT. (author)
Energy Technology Data Exchange (ETDEWEB)
McWilliams, T.; Widdoes, Jr., L. C.; Wood, L.
1976-09-30
The design of an extremely high performance programmable digital filter of novel architecture, the LLL Programmable Digital Filter, is described. The digital filter is a high-performance multiprocessor having general purpose applicability and high programmability; it is extremely cost effective either in a uniprocessor or a multiprocessor configuration. The architecture and instruction set of the individual processor was optimized with regard to the multiple processor configuration. The optimal structure of a parallel processing system was determined for addressing the specific Navy application centering on the advanced digital filtering of passive acoustic ASW data of the type obtained from the SOSUS net. 148 figures. (RWR)
Experimental data required for the design and analysis of emergency filtered air discharge sytems
International Nuclear Information System (INIS)
The radiological consequences of an accident in a CANDU nuclear generating station are mitigated by special safety systems which include an Emergency Filtered Air Discharge (EFAD) system. EFAD systems are designed to provide a controlled leakage path following an accident. They remove radioiodine and particulates from the air discharge required, to inhibit uncontrolled emissions by maintaining containment sub-atmospheric in the long term. The design and analysis of an EFAD system requires an accurate data base comprised of the numerous parameters involved in the simulation of fission product behaviour within containment. This paper emphasizes the data requirements of EFAD system design with regard to those parameters which preliminary sensitivity analyses have shown to most effect environmental releases. These include the source term radioisotopes; their chemical behaviour and distribution within containment; the repressurization time during the vacuum hold-up period; and parameters effecting the long term releases through the EFAD system. The net radioiodine trapping efficiency of charcoal filters in the long term is dependent on the adsorption efficiency and desorption of the deep charcoal bed. These are a function of many parameters such as impregnate, aging, humidity, temperature, radiation, recirculation, etc. Although the effect of these parameters on charcoal filters has been individually investigated, generally at ideal or extreme values, there is little applicable data to determine their combined effect under expected post accident operating conditions. As a consequence, designers tend to overdesign by using unduly conservative parameters. A summary comparison is presented to illustrate the information gap between the experimental data from the literature and the data required for optimal design and analysis of the EFAD systems
Directory of Open Access Journals (Sweden)
Chiung-An Chen
2012-11-01
Full Text Available In this paper, a low-cost, low-power and high performance micro control unit (MCU core is proposed for wireless body sensor networks (WBSNs. It consists of an asynchronous interface, a register bank, a reconfigurable filter, a slop-feature forecast, a lossless data encoder, an error correct coding (ECC encoder, a UART interface, a power management (PWM, and a multi-sensor controller. To improve the system performance and expansion abilities, the asynchronous interface is added for handling signal exchanges between different clock domains. To eliminate the noise of various bio-signals, the reconfigurable filter is created to provide the functions of average, binomial and sharpen filters. The slop-feature forecast and the lossless data encoder is proposed to reduce the data of various biomedical signals for transmission. Furthermore, the ECC encoder is added to improve the reliability for the wireless transmission and the UART interface is employed the proposed design to be compatible with wireless devices. For long-term healthcare monitoring application, a power management technique is developed for reducing the power consumption of the WBSN system. In addition, the proposed design can be operated with four different bio-sensors simultaneously. The proposed design was successfully tested with a FPGA verification board. The VLSI architecture of this work contains 7.67-K gate counts and consumes the power of 5.8 mW or 1.9 mW at 100 MHz or 133 MHz processing rate using a TSMC 0.18 μm or 0.13 μm CMOS process. Compared with previous techniques, this design achieves higher performance, more functions, more flexibility and higher compatibility than other micro controller designs.
Chen, Chiung-An; Chen, Shih-Lun; Huang, Hong-Yi; Luo, Ching-Hsing
2012-01-01
In this paper, a low-cost, low-power and high performance micro control unit (MCU) core is proposed for wireless body sensor networks (WBSNs). It consists of an asynchronous interface, a register bank, a reconfigurable filter, a slop-feature forecast, a lossless data encoder, an error correct coding (ECC) encoder, a UART interface, a power management (PWM), and a multi-sensor controller. To improve the system performance and expansion abilities, the asynchronous interface is added for handling signal exchanges between different clock domains. To eliminate the noise of various bio-signals, the reconfigurable filter is created to provide the functions of average, binomial and sharpen filters. The slop-feature forecast and the lossless data encoder is proposed to reduce the data of various biomedical signals for transmission. Furthermore, the ECC encoder is added to improve the reliability for the wireless transmission and the UART interface is employed the proposed design to be compatible with wireless devices. For long-term healthcare monitoring application, a power management technique is developed for reducing the power consumption of the WBSN system. In addition, the proposed design can be operated with four different bio-sensors simultaneously. The proposed design was successfully tested with a FPGA verification board. The VLSI architecture of this work contains 7.67-K gate counts and consumes the power of 5.8 mW or 1.9 mW at 100 MHz or 133 MHz processing rate using a TSMC 0.18 μm or 0.13 μm CMOS process. Compared with previous techniques, this design achieves higher performance, more functions, more flexibility and higher compatibility than other micro controller designs. PMID:23443375
Design of Low Power Column Bypass Multiplier using FPGA and Implementation Using FIR Filter
Directory of Open Access Journals (Sweden)
Vemula Prakash
2013-09-01
Full Text Available Design of area, high speed and power efficient data path logic systems in the low power VLSI circuits has been identified as vital technology in the in the DSP computations and signal processing applications like FIR,IIR filters. Since multipliers consume most of the power in DSP computations it is very important to develop new low-power multipliers for DSP computations. The switching activity of the multiplier depends on the input bit-coefficient, if the coefficient bits are zero the corresponding rows or columns need not to be activated. By inserting more number of zeros in the multiplicand using booth recoding unit we can reduce the switching activity by shutting down the idle part of the circuit and thereby reducing the power dissipation, based on this concept we presents low power column bypass multiplier and verifies the result using FIR filter
Design and manufacture of a bandpass filter with high transmittance and steep edge on both sides
Wang, Ruisheng; Lü, Shaobo; Yin, Xiaojun; Zhao, Shuaifeng; Sun, Yan
2016-01-01
By using Nb2O5 and SiO2 as the coating material, a 152 layers (12 cavities) bandpass film stack with steep edge on both sides was designed. Multiple thickness control methods, including direct optical monitoring control and time control were used in coating strategy. To confirm the feasibility of this coating strategy, a process simulation was performed using Simulator software, and the simulation result indicated that relative thickness errors for all layers were less than ±0.1%. A bandpass filter with this film stack on one side was manufactured by using a plasma assisted reactive magnetic sputtering coating machine. The measuring result shows that the peak transmittance of the filter (without AR on backside) is up to 95.4%, and the steepness of both blocking slope are less than λ/100.
International Nuclear Information System (INIS)
Double-shell tanks (DSTs) and Double Contained Receiver Tanks (DCRTs) are actively ventilated, along with certain single-shell tanks (SSTs) and other RPP facilities. The exhaust air stream on a typical primary ventilation system is drawn through two stages of high-efficiency particulate air (HEPA) filtration to ensure confinement of airborne radioactive materials. Active ventilation exhaust stacks require a stack CAM interlock to detect releases from postulated accidents, and to shut down the exhaust fan when high radiation levels are detected in the stack airstream. The stack CAM interlock is credited as a mitigating control to stop continued unfiltered radiological and toxicological discharges from the stack, which may result from an accident involving failure of a HEPA filter. This document defines the initial technical design baseline for a HEPA filter AP fan interlock system
Design of metallic nanoparticles gratings for filtering properties in the visible spectrum
Brûlé, Y; Fehrembach, A -L; Gralak, B; Popov, E; Tayeb, G; Grangier, M; Barat, D; Bertin, H; Gogol, P; Dagens, B
2015-01-01
Plasmonic resonances in metallic nanoparticles are exploited to create efficient optical filtering functions. A Finite Element Method is used to model metallic nanoparticles gratings. The accuracy of this method is shown by comparing numerical results with measurements on a two-dimensional grating of gold nanocylinders with elliptic cross section. Then a parametric analysis is performed in order to design efficient filters with polarization dependent properties together with high transparency over the visible range. The behavior of nanoparticle gratings is also modelled using the Maxwell-Garnett homogenization theory and analyzed by comparison with the diffraction by a single nanoparticle. The proposed structures are intended to be included in optical systems which could find innovative applications.
Energy Technology Data Exchange (ETDEWEB)
TUCK, J.A.
2000-05-11
Double-shell tanks (DSTs) and Double Contained Receiver Tanks (DCRTs) are actively ventilated, along with certain single-shell tanks (SSTs) and other RPP facilities. The exhaust air stream on a typical primary ventilation system is drawn through two stages of high-efficiency particulate air (HEPA) filtration to ensure confinement of airborne radioactive materials. Active ventilation exhaust stacks require a stack CAM interlock to detect releases from postulated accidents, and to shut down the exhaust fan when high radiation levels are detected in the stack airstream. The stack CAM interlock is credited as a mitigating control to stop continued unfiltered radiological and toxicological discharges from the stack, which may result from an accident involving failure of a HEPA filter. This document defines the initial technical design baseline for a HEPA filter AP fan interlock system.
Design and evaluation of a HDR skin applicator with flattening filter.
Granero, D; Pérez-Calatayud, J; Gimeno, J; Ballester, F; Casal, E; Crispín, V; van der Laarse, R
2008-02-01
The purposes of this study are: (i) to design field flattening filters for the Leipzig applicators of 2 and 3 cm of inner diameter with the source traveling parallel to the applicator contact surface, which are accessories of the microSelectron-HDR afterloader (Nucletron, Veenendaal, The Netherlands). These filters, made of tungsten, aim to flatten the heterogeneous dose distribution obtained with the Leipzig applicators. (ii) To estimate the dose rate distributions for these Leipzig+filter applicators by means of the Monte Carlo (MC) method. (iii) To experimentally verify these distributions for prototypes of these new applicators, and (iv) to obtain the correspondence factors to measure the output of the applicators by the user using an insert into a well chamber. The MC GEANT4 code has been used to design the filters and to obtain the dose rate distributions in liquid water for the two Leipzig+filter applicators. In order to validate this specific application and to guarantee that realistic source-applicator geometry has been considered, an experimental verification procedure was implemented in this study, in accordance with the updated recommendations of the American Association of Physicists in Medicine Task Group No. 43 U1 Report. Thermoluminescent dosimeters, radiochromic film, and a pin-point ionization chamber in a plastic [polymethylmethacrylate (PMMA)] phantom were used to verify the MC results for the two applicators of a microSelectron-HDR afterloader with the mHDR-v2 source. To verify the output of the Leipzig +filter applicators, correspondence factors were deduced for the well chambers HDR100-plus (Standard Imaging, Inc., Middleton, WI) and TM33004 (PTW, Freiburg, Germany) using a specific insert for both applicators. The doses measured in the PMMA phantom agree within experimental uncertainties with the dose obtained by the MC calculations. Percentage depth dose and off-axis profiles were obtained normalized at a depth of 3 mm along the central
Chang, Gao-Wei; Jian, Hong-Da; Yeh, Zong-Mu; Cheng, Chin-Pao
2004-02-01
For estimating spectral responsivities of digital video cameras, a filter-based optical system is designed with sophisticated filter selections, in this paper. The filter consideration in the presence of noise is central to the optical systems design, since the spectral filters primarily prescribe the structure of the perturbed system. A theoretical basis is presented to confirm that sophisticated filter selections can make this system as insensitive to noise as possible. Also, we propose a filter selection method based on the orthogonal-triangular (QR) decomposition with column pivoting (QRCP). To investigate the noise effects, we assess the estimation errors between the actual and estimated spectral responsivities, with the different signal-to-noise ratio (SNR) levels of an eight-bit/channel camera. Simulation results indicate that the proposed method yields satisfactory estimation accuracy. That is, the filter-based optical system with the spectral filters selected from the QRCP-based method is much less sensitive to noise than those with other filters from different selections.
Hu, Jun; Liu, Steven; Ji, Donghai; Li, Shanqiang
2016-07-01
In this paper, the co-design problem of filter and fault estimator is studied for a class of time-varying non-linear stochastic systems subject to randomly occurring nonlinearities and randomly occurring deception attacks. Two mutually independent random variables obeying the Bernoulli distribution are employed to characterize the phenomena of the randomly occurring nonlinearities and randomly occurring deception attacks, respectively. By using the augmentation approach, the co-design problem of the robust filter and fault estimator is converted into the recursive filter design problem. A new compensation scheme is proposed such that, for both randomly occurring nonlinearities and randomly occurring deception attacks, an upper bound of the filtering error covariance is obtained and such an upper bound is minimized by properly designing the filter gain at each sampling instant. Moreover, the explicit form of the filter gain is given based on the solution to two Riccati-like difference equations. It is shown that the proposed co-design algorithm is of a recursive form that is suitable for online computation. Finally, a simulation example is given to illustrate the usefulness of the developed filtering approach.
International Nuclear Information System (INIS)
In this paper, to increase the DF for gaseous iodine species, especially organic iodide, molecular sieve filled by silver exchanged zeolites is proposed and designed preliminarily. Its aerodynamic analysis is also performed and presented. In order to increase the DF for gaseous organic iodide, deep-bed type molecular sieve was proposed and designed preliminarily. Total 1,620kg of silver exchanged zeolites were filled evenly in 10 beds of the molecular sieve. The safety factor in the case of 20m3/s will be smaller than the counterpart of the standard case (6m3/s). However, if the adsorption capacity of the zeolites is larger than 3.09mg/g when the residence time is 0.09 second, the designed molecular sieve can be used at 20m3/s of volumetric flow rate. The removal efficiency for organic iodide should be considered as well as economical aspects in the design of molecular sieve. In the event of nuclear power plant (NPP) severe accident, the nuclear reactor containment might suffer damage resulting from overpressure caused by decay heat. In order to prevent this containment damage, containment venting has been considered as one of effective methods. However, since vented gases contain radioactive fission products, they should be filtered to be released to environment. Generally, containment filtered venting system (CFVS) is installed on NPP to achieve this aim. Even though great amount of efforts have been devoted to developing the CFVS using various filtering methods, the decontaminant factor (DF) for radioactive gaseous iodide is still unsatisfactory while DFs for radioactive aerosols and elemental iodine are very high
INEL BNCT research program publications, 1993
International Nuclear Information System (INIS)
This document is a collection of the published reports describing research supporting the Idaho National Engineering Laboratory Boron Neutron Capture Therapy Research Program for calendar year 1993. Contributions from the principal investigators are included, covering chemistry (pituitary tumor studies, boron drug development including liposomes, lipoproteins, and carboranylalanine derivatives), pharmacology (murine screenings, toxicity testing, ICP-AES analysis of biological samples), physics (radiation dosimetry software, neutron beam and filter design, neutron beam measurement dosimetry), and radiation biology (tissue and efficacy studies of small and large animal models). These reports have previously appeared in the book: Advances in Neutron Capture Therapy, edited by A. H. Soloway, R. F. Barth, D. E. Carpenter, Plenum Press, 1993. Reports have also appeared in three journals: Angewandte Chemie, Strahlentherapie und Onkologie, and Nuclear Science and Engineering. This individual papers have been indexed separately elsewhere
Feasibility of BNCT radiobiological experiments at the HYTHOR facility
Esposito, J.; Ceballos, C.; Soncin, M.; Fabris, C.; Friso, E.; Moro, D.; Colautti, P.; Jori, G.; Rosi, G.; Nava, E.
2008-06-01
HYTHOR (HYbrid Thermal spectrum sHifter tapirO Reactor) is a new thermal-neutron irradiation facility, which was installed and became operative in mid 2005 at the TAPIRO (TAratura PIla Rapida potenza 0) fast reactor, in the Casaccia research centre (near Rome) of ENEA (Ente per le Nuove tecnologie Energia ed Ambiente). The facility has been designed for in vivo radiobiological studies. In HYTHOR irradiation cavity, 1-6 mice can be simultaneously irradiated to study skin melanoma treatments with the BNCT (boron neutron capture therapy). The therapeutic effects of HYTHOR radiation field on mouse melanoma has been studied as a preliminary investigation before studying the tumour local control due to boron neutron capture effect after boronated molecule injection. The method to properly irradiate small animals has been precisely defined. Results show that HYTHOR radiation field is by itself effective in reducing the tumour-growth rate. This finding has to be taken into account in studying the effectiveness of new 10B carriers. A method to properly measure the reduction of the tumour-growth rate is reported and discussed.
Frankel, R. J.
1981-05-01
A simple, inexpensive, and efficient method of water treatment for rural communities in Southeast Asia was developed using local materials as filter media. The filter utilizes coconut fiber and burnt rice husks in a two-stage filtering process designed as a gravityfed system without the need for backwashing, and eliminates in most cases the need of any chemicals. The first-stage filter with coconut fiber acts essentially as a substitute for the coagulation and sedimentation phases of conventional water-treatment plants. The second-stage filter, using burnt rice husks, is similar to slow sand filtration with the additional benefits of taste, color and odor removals through the absorption properties of the activated carbon in the medium. This paper reports on the design, construction costs, and operating results of several village size units in Thailand and in the Philippines.
Directory of Open Access Journals (Sweden)
Abhijit Chandra
2013-09-01
Full Text Available Signal processing of present era is becoming more and more complex day by day. To meet the demand of modern signal processing, emphasis has been given to develop systems with minimum hardware. As a matter of fact, reduction in hardware complexity of digital filter has emerged as one of the upcoming research areas in present time. This paper highlights the design of multiplier-less finite impulse response (FIR filter with the aid of an evolutionary optimization technique, namely Self-organizing Random Immigrants Genetic Algorithm (SORIGA. For this purpose, the coefficients of the filter have been encoded by binary and Canonic Signed Digit (CSD number systems and subsequently optimized by means of SORIGA. Performance of the proposed filter has been analyzed in terms of its frequency and impulse response. Subsequently, hardware cost of the designed filter has been measured by means of a number of performance parameters and compared with few s
Directory of Open Access Journals (Sweden)
Jawad K. Ali
2008-01-01
Full Text Available A novel fractal design scheme has been introduced in this paper to generate microstrip bandpass filter designs with miniaturized sizes for wireless applications. The presented fractal scheme is based on Minkowski-like prefractal geometry. The space-filling property and self-similarity of this fractal geometry has found to produce reduced size symmetrical structures corresponding to the successive iteration levels. The resulting filter designs are with sizes suitable for use in modern wireless communication systems. The performance of each of the generated bandpass filter structures up to the 2nd iteration has been analyzed using a method of moments (MoM based software IE3D, which is widely adopted in microwave research and industry. Results show that these filters possess good transmission and return loss characteristics, besides the miniaturized sizes meeting the design specifications of most of wireless communication systems
DEFF Research Database (Denmark)
Tang, Yi; Yao, Wenli; Loh, Poh Chiang;
2015-01-01
This paper proposes a novel LCL-filter design method and its current control for grid-connected converters. With the proposed design method, it is possible to set the resonance frequency of the LCL-filter to be higher than the Nyquist frequency, i.e. half of the system sampling frequency, and this...... observation is so far not discussed in the literature. In this case, very cost-effective LCL-filter design can be achieved for grid-connected converters whose dominant switching harmonics may appear at double of the switching frequency, e.g. in unipolar modulated three-level full bridge converters and 12...... current and excellent resonance attenuation are presented in the paper, which are also in very good agreement with those simulated ones. These results successfully verify the feasibility of the proposed LCL-filter design and its current control....
International Nuclear Information System (INIS)
The treatment and disposal of spent high-efficiency particulate air (HEPA) filters has presented a problem at some defense production plants and could be a problem at potential future spent-fuel consolidation or fuel reprocessing facilities. During studies of transuranic (TRU) waste treatment options conducted by Pacific Northwest Laboratory, it was concluded that treatment of spent HEPA filters would become easier and less costly if some modifications were made to the present materials of construction and design. This study was undertaken to develop and evaluate alternative materials and innovative designs for HEPA filters, making them more compatible with volume reduction technology. The following treatment options were selected for this study: (1) no treatment; (2) compaction; (3) supercompaction; (4) incinerate and melt; and (5) separate the frame from the media and dispose of the frame as low-level waste, and incinerate and melt the filter media and sealant. Forty HEPA design concepts were identified and evaluated by means of a figure-of-merit methodology for technical performance and an economic evaluation that considered filter fabrication and disposal costs. Results of the study indicate that if improved HEPA designs are combined with volume reduction treatments, the costs of filter disposal can be reduced substantially over the use of standard-flow filter designs with no volume reduction treatment. It is estimated that by combining the new design concepts with waste volume reduction treatments, manufacturing and disposal costs can be reduced by $290 or more per filter if classified as low-level waste (LLW) and up to $23,000 per filter if it is high-activity waste (containing activity greater than class-C LLW) and requires repository disposal
Yang Yi; Yue-Yue Zhao; Song-Yin Cao
2013-01-01
This paper studies the fuzzy modeling problem and the fault detection and diagnosis (FDD) algorithm for non-Gaussian stochastic distribution systems based on the nonlinear fuzzy filter design. Following spline function approximation for output probability density functions (PDFs), the T-S fuzzy model is built as a nonlinear identifier to describe the dynamic relationship between the control input and the weight vector. By combining the designed filter and the threshold value, the fault in T-S...
A New Mutated Quantum-Behaved Particle Swarm Optimizer for Digital IIR Filter Design
Directory of Open Access Journals (Sweden)
Wenbo Xu
2009-01-01
Full Text Available Adaptive infinite impulse response (IIR filters have shown their worth in a wide range of practical applications. Because the error surface of IIR filters is multimodal in most cases, global optimization techniques are required for avoiding local minima. In this paper, we employ a global optimization algorithm, Quantum-behaved particle swarm optimization (QPSO that was proposed by us previously, and its mutated version in the design of digital IIR filter. The mechanism in QPSO is based on the quantum behaviour of particles in a potential well and particle swarm optimization (PSO algorithm. QPSO is characterized by fast convergence, good search ability, and easy implementation. The mutated QPSO (MuQPSO is proposed in this paper by using a random vector in QPSO to increase the randomness and to enhance the global search ability. Experimental results on three examples show that QPSO and MuQPSO are superior to genetic algorithm (GA, differential evolution (DE algorithm, and PSO algorithm in quality, convergence speed, and robustness.
A Design of a Terahertz Microstrip Bandstop Filter with Defected Ground Structure
Directory of Open Access Journals (Sweden)
Arjun Kumar
2013-01-01
Full Text Available A planar microstrip terahertz (THz bandstop filter has been proposed with defected ground structure with high insertion loss (S21 in a stopband of −25.8 dB at 1.436 THz. The parameters of the circuit model have been extracted from the EM simulation results. A dielectric substrate of Benzocyclobutene (BCB is used to realize a compact bandstop filter using modified hexagonal dumbbell-shape defected ground structure (DB-DGS. In this paper, a defected ground structure topology is used in a λ/4, 50 Ω microstrip line at THz frequency range for compactness. No article has been reported on the microstrip line at terahertz frequency regime using DGS topology. The proposed filter can be used for sensing and detection in biomedical instruments in DNA testing. All the simulations/cosimulations are carried out using a full-wave EM simulator CST V.9 Microwave Studio, HFSS V.10, and Agilent Design Suite (ADS.
Pre-processing filter design at transmitters for IBI mitigation in an OFDM system
Institute of Scientific and Technical Information of China (English)
Xia Wang; Lei Wang
2013-01-01
In order to meet the demands for high transmission rates and high service quality in broadband wireless communica-tion systems, orthogonal frequency division multiplexing (OFDM) has been adopted in some standards. However, the inter-block interference (IBI) and inter-carrier interference (ICI) in an OFDM system affect the performance. To mitigate IBI and ICI, some pre-processing approaches have been proposed based on ful channel state information (CSI), which improved the system per-formance. A pre-processing filter based on partial CSI at the trans-mitter is designed and investigated. The filter coefficient is given by the optimization processing, the symbol error rate (SER) is tested, and the computation complexity of the proposed scheme is analyzed. Computer simulation results show that the proposed pre-processing filter can effectively mitigate IBI and ICI and the performance can be improved. Compared with pre-processing approaches at the transmitter based on ful CSI, the proposed scheme has high spectral efficiency, limited CSI feedback and low computation complexity.
International Nuclear Information System (INIS)
Boron Neutron Capture Therapy (BNCT) is a binary treatment modality based on the capture reaction that occurs between thermal neutrons and boron-10 atoms that accumulate selectively in tumor tissue, emitting high linear energy transfer (LET), short range (5-9 microns) particles (alpha y 7Li). Thus, BNCT would potentially target tumor tissue selectively, sparing normal tissue. Herein we evaluated the feasibility of treating experimental oral mucosa tumors with BNCT at RA-3 (CAE) employing the hamster cheek pouch oral cancer model and characterized the irradiation field at the RA-3 facility. We evaluated the therapeutic effect on tumor of BNCT mediated by BPA in the hamster cheek pouch oral cancer model and the potential radio toxic effects in normal tissue. We evidenced a moderate biological response in tumor, with no radio toxic effects in normal tissue following irradiations with no shielding for the animal body. Given the sub-optimal therapeutic response, we designed and built a 6Li2CO3 shielding for the body of the animal to increase the irradiation dose to tumor, without exceeding normal tissue radio tolerance. The measured absolute magnitude of thermal neutron flux and the characterization of the beam with and without the shielding in place, suggest that the irradiation facility in the thermal column of RA-3 would afford an excellent platform to perform BNCT studies in vitro and in vivo in small experimental animals. The present findings must be confirmed and extended by performing in vivo BNCT radiobiological studies in small experimental animals, employing the shielding device for the animal body. (author)
International Nuclear Information System (INIS)
In this paper, we have proposed a new design of tunable two dimensional (2D) photonic crystal (PhC) channel drop filter (CDF) using ring resonators. The increasing interest in photonic integrated circuits (PIC's) and the increasing use of all-optical fiber networks as backbones for global communication systems have been based in large part on the extremely wide optical transmission bandwidth provided by dielectric materials. Based on the analysis we present novel photonic crystal channel drop filters. Simulations demonstrate that these filters exhibit ideal transfer characteristics. Channel dropping filters (CDF's) that access one channel of a wavelength division multiplexed (WDM) signal while leaving other channels undisturbed are essential components of PIC's and optical communication systems. In this paper we have investigated such parameters which have an effect on resonant wavelength in this Channel Drop Filter, such as dielectric constant of inner, coupling, adjacent and whole rods of the structure. The dimensions of these structures are taken as 20a×19a and the area of the proposed structure is about 125.6μm2; therefore this structure can be used in the future photonic integrated circuits. While using this design the dropping efficiency at the resonance of single ring are 100%. The spectrum of the power transmission is obtained with finite difference time domain (FDTD) method. FDTD method is the most famous method for PhC analysis. In this paper the dielectric rods have a dielectric constant of 10.65, so the refractive index is 3.26 and radius r=0.213a is located in air, where a is a lattice constant. In this we have used five scatter rods for obtaining more coupling efficiency; radius of scatter rods is set to 0.215a. The proposed structure is simulated with OptiFDTD.v.8.0 software, the different dielectric constant of rods equal to εr−0.4, εr and εr+0.4 at wavelength of 1570 nm
Plasma grid design for optimized filter field configuration for the NBI test facility ELISE
Energy Technology Data Exchange (ETDEWEB)
Nocentini, R. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, D-85740 Garching (Germany)], E-mail: riccardo.nocentini@ipp.mpg.de; Gutser, R.; Heinemann, B.; Froeschle, M.; Riedl, R. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, D-85740 Garching (Germany)
2009-12-15
Maintenance-free RF sources for negative hydrogen ions with moderate extraction areas (100-200 cm{sup 2}) have been successfully developed in the last years at IPP Garching in the test facilities BATMAN and MANITU. A facility with larger extraction area (1000 cm{sup 2}), ELISE, is being designed with a 'half-size' ITER-like extraction system, pulsed ion acceleration up to 60 kV for 10 s and plasma generation up to 1 h. Due to the large size of the source, the magnetic filter field (FF) cannot be produced solely by permanent magnets. Therefore, an additional magnetic field produced by current flowing through the plasma grid (PG current) is required. The filter field homogeneity and the interaction with the electron suppression magnetic field have been studied in detail by finite element method (FEM) during the ELISE design phase. Significant improvements regarding the field homogeneity have been introduced compared to the ITER reference design. Also, for the same PG current a 50% higher field in front of the grid has been achieved by optimizing the plasma grid geometry. Hollow spaces have been introduced in the plasma grid for a more homogeneous PG current distribution. The introduction of hollow spaces also allows the insertion of permanent magnets in the plasma grid.
Directory of Open Access Journals (Sweden)
Moret Nicola
2010-01-01
Full Text Available Abstract We address the efficient realization of a filtered multitone (FMT modulation system and its orthogonal design. FMT modulation can be viewed as a Discrete Fourier Transform (DFT modulated filter bank (FB. It generalizes the popular orthogonal frequency division multiplexing (OFDM scheme by deploying frequency confined subchannel pulses. We compare three realizations that have been described by Cvetković and Vetterli (1998, and Weiss and Stewart (2000, and Tonello (2006. A detailed derivation of them is performed in the time-domain via the exploitation of different FB polyphase decompositions. We then consider the design of an orthogonal FMT system and we exploit the third realization which allows simplifying the orthogonal FB design and obtaining a block diagonal system matrix with independent subblocks. A numerical method is then presented to obtain an orthogonal FB with well frequency confined subchannel pulses for arbitrarily large number of subchannels. Several examples of pulses with minimal length are reported and their performance is evaluated in typical multipath fading channels. Finally, we compare the orthogonal FMT system with a cyclically prefixed OFDM system in the IEEE 802.11 wireless LAN channel. In this scenario, FMT with minimal length pulses and single tap subchannel equalization outperforms the OFDM system in achievable rate.
Directory of Open Access Journals (Sweden)
Andrea M. Tonello
2010-01-01
Full Text Available We address the efficient realization of a filtered multitone (FMT modulation system and its orthogonal design. FMT modulation can be viewed as a Discrete Fourier Transform (DFT modulated filter bank (FB. It generalizes the popular orthogonal frequency division multiplexing (OFDM scheme by deploying frequency confined subchannel pulses. We compare three realizations that have been described by Cvetković and Vetterli (1998, and Weiss and Stewart (2000, and Tonello (2006. A detailed derivation of them is performed in the time-domain via the exploitation of different FB polyphase decompositions. We then consider the design of an orthogonal FMT system and we exploit the third realization which allows simplifying the orthogonal FB design and obtaining a block diagonal system matrix with independent subblocks. A numerical method is then presented to obtain an orthogonal FB with well frequency confined subchannel pulses for arbitrarily large number of subchannels. Several examples of pulses with minimal length are reported and their performance is evaluated in typical multipath fading channels. Finally, we compare the orthogonal FMT system with a cyclically prefixed OFDM system in the IEEE 802.11 wireless LAN channel. In this scenario, FMT with minimal length pulses and single tap subchannel equalization outperforms the OFDM system in achievable rate.
Reshetov, Vlad; Fitzsimmons, Joeleff
2008-07-01
This paper presents a design of a variable size spatial filter used in the wavefront sensor subsystem of the Gemini Planet Imager instrument. It describes an adjustable mechanism consisting of two slides forming a square aperture which can be varied in size between 1.8 and 6.7 mm. These slides are located on athermalized flexure mounts that move opposite to one another driven by a single precision linear actuator. The device retains long term dimensional stability, resolution, and repeatability on a micron level for all gravity vector orientations and for temperatures between -5°C and + 25°C.
On new design of Kalman filter with entry-wise updating
Czech Academy of Sciences Publication Activity Database
Suzdaleva, Evgenia
Santader: WSEAS, 2008, s. 246-251. ISBN 978-960-474-007-9. [8th WSEAS International Conference on Simulation, Modelling and Optimization (SMO'08). Santader (ES), 23.09.2008-25.09.2008] R&D Projects: GA ČR(CZ) GP201/06/P434 Institutional research plan: CEZ:AV0Z10750506 Keywords : factorized ﬁltering * Kalman ﬁlter * state estimation Subject RIV: BC - Control Systems Theory http://library.utia.cas.cz/separaty/2008/AS/suzdaleva-on%20new%20design%20of%20kalman%20filter%20with%20entry-wise%20updating.pdf
A Novel Magnetic Linear Encoder Designed by Using the Slant Multi-Phase Filtering Model
Institute of Scientific and Technical Information of China (English)
SHI Yu; XING Huai-Zhong; ZHANG Huai-Wu; LIU Ying-Li; JING Yu-Lan; ZHONG Zhi-Yong
2004-01-01
@@ A novel design model based on the slant multi-phase filtering model is presented. A magnetic linear encoder with sinusoidal output voltage waveform has been investigated, and the improved sinusoidal output waveform can be easily acquired. A minimum 6% of distortion factor, when the difference of slant phase is 2π/3, is observed. It is found that the Wheatstone bridge type sensor, made of NiFe(450A)/NiO(300A) bilayers deposited on Si (001)substrate, can enhance both output signal and thermal stability, and then can be widely used in the field of magneto-resistive sensor.
DEFF Research Database (Denmark)
Jørgensen, Mette Marie; Petersen, Sidsel Rübner; Laurila, Marko; Lægsgaard, Jesper; Alkeskjold, Thomas T.
2012-01-01
High-power fiber amplifiers for pulsed applications require large mode area (LMA) fibers having high pump absorption and near diffraction limited output. This improves the limiting factor of nonlinear effects, while maintaining good beam quality. Photonic crystal fibers allow realization of short...... LMA fiber amplifiers having high pump absorption through a pump cladding that is decoupled from the outer fiber. However, achieving ultra low NA for single-mode (SM) guidance is challenging, and thus different design strategies must be applied to filter out higher order modes (HOMs). The novel...
Protocols for BNCT of glioblastoma multiforme at Brookhaven: Practical considerations
Energy Technology Data Exchange (ETDEWEB)
Chanana, A.D.; Coderre, J.A.; Joel, D.D.; Slatkin, D.N.
1996-12-31
In this report we discuss some issues considered in selecting initial protocols for boron neutron capture therapy (BNCT) of human glioblastoma multiforme. First the tolerance of normal tissues, especially the brain, to the radiation field. Radiation doses limits were based on results with human and animal exposures. Estimates of tumor control doses were based on the results of single-fraction photon therapy and single fraction BNCT both in humans and experimental animals. Of the two boron compounds (BSH and BPA), BPA was chosen since a FDA-sanctioned protocol for distribution in humans was in effect at the time the first BNCT protocols were written and therapy studies in experimental animals had shown it to be more effective than BSH.
Proceedings of neutron irradiation technical meeting on BNCT
Energy Technology Data Exchange (ETDEWEB)
NONE
2000-10-01
The 'Neutron Irradiation Technical Meeting for Boron Neutron Capture Therapy (BNCT)' was held on March 13, 2000 at Tokai Research Establishment. The Meeting is aimed to introduce the neutron beam facility for medical irradiation at JRR-4 to Japanese researchers widely, as well as providing an opportunity for young researchers, engineers, medical representatives such surgeons and doctors of pharmacology to present their research activities and to exchange valuable information. JAERI researcher presented the performance and the irradiation technology in the JRR-4 neutron beam facility, while external researchers made various and beneficial presentations containing such accelerator-based BNCT, spectrum-shifter, biological effect, pharmacological development and so on. In this meeting, a special lecture titled 'The Dawn of BNCT and Its Development.' was given by MD, Prof. Takashi Minobe, an executive director of Japan Foundation for Emergency Medicine. The 11 of the presented papers are indexed individually. (J.P.N.)
An efficient closed-form design method for nearly perfect reconstruction of non-uniform filter bank.
Kumar, A; Pooja, R; Singh, G K
2016-03-01
In this paper, an efficient closed form method for the design of multi-channel nearly perfect reconstruction of non-uniform filter bank with the prescribed stopband attenuation and channel overlapping is presented. In this method, the design problem of multi-channel non-uniform filter bank (NUFB) is considered as the design of a prototype filter whose magnitude response at quadrature frequency is 0.707, which is exploited for finding the optimum passband edge frequency through empirical formula instead of using single or multivariable optimization technique. Two main attributes used in assessing the performance of filter bank are peak reconstruction error (PRE) and computational time (CPU time). As compared to existing methods, this method is very simple and easy to implement for NUFBs. To implement this algorithm, a Matlab program has been developed, and several examples are presented to illustrate the performance of proposed method. PMID:26861726
DEFF Research Database (Denmark)
Tang, Yi; Yao, Wenli; Loh, Poh Chiang;
2016-01-01
This paper proposes a novel LCL filter design method and its current control for grid-connected converters. With the proposed design method, it is possible to set the resonance frequency of the LCL filter to be higher than the Nyquist frequency, i.e., half of the system sampling frequency, and this...... observation is so far not discussed in the literature. In this case, a very cost-effective LCL filter design can be achieved for the grid-connected converters, whose dominant switching harmonics may appear at double the switching frequency, e.g., in unipolar-modulated three-level full-bridge converters and 12...... examples are given, with one of them optimizing the utilization of passive filter inductors, and another one being robust against grid impedance variation. Comprehensive experimental results, showing the high-quality output current and excellent resonance attenuation, are presented in this paper, which are...
Design of a bed load and driftwood filtering dam, analysis of the phenomena and hydraulic design
Schleiss, Anton; Speerli, J.; Pfammatter, Roger; Bianco-Riccioz, Manuella; Bianco, Philippe; De Cesare, Giovanni
2014-01-01
Flood protection often calls on to the realization of retention works for bed load as well as wood and debris flow. Certain relatively recent arrangements did not perform according to their intended function, what shows the complexity of the design and the implementation of such works. Adaptations were necessary to reach the security objectives. The design of a retention dam for solid materials and floating driftwood requires the consideration of numerous hydraulic and material transport proc...
de Lamare, R C; Fa, R
2012-01-01
This paper presents reduced-rank linearly constrained minimum variance (LCMV) beamforming algorithms based on joint iterative optimization of filters. The proposed reduced-rank scheme is based on a constrained joint iterative optimization of filters according to the minimum variance criterion. The proposed optimization procedure adjusts the parameters of a projection matrix and an adaptive reducedrank filter that operates at the output of the bank of filters. We describe LCMV expressions for the design of the projection matrix and the reduced-rank filter. We then describe stochastic gradient and develop recursive least-squares adaptive algorithms for their efficient implementation along with automatic rank selection techniques. An analysis of the stability and the convergence properties of the proposed algorithms is presented and semi-analytical expressions are derived for predicting their mean squared error (MSE) performance. Simulations for a beamforming application show that the proposed scheme and algorit...
Murata, Isao; Nakamura, Soichiro; Manabe, Masanobu; Miyamaru, Hiroyuki; Kato, Itsuro
2014-06-01
Author׳s group is carrying out development of BNCT-SPECT with CdTe device, which monitors the therapy effect of BNCT in real-time. From the design calculations, the dimensions were fixed to 1.5×2×30mm(3). For the collimator it was confirmed that it would have a good spatial resolution and simultaneously the number of counts would be acceptably large. After producing the CdTe crystal, the characterization measurement was carried out. For the detection efficiency an excellent agreement between calculation and measurement was obtained. Also, the detector has a very good energy resolution so that gamma-rays of 478keV and 511keV could be distinguished in the spectrum. PMID:24581600
Energy Technology Data Exchange (ETDEWEB)
Meyer, Robert; Mertens, Axel [Hannover Univ. (DE). Inst. fuer Antriebssysteme und Leistungselektronik (IAL)
2011-07-01
This paper describes a method for designing LCL filters to be used in decentralized power generating plants. It is especially suitable for converters with low switching frequency and/or converters with modulation methods generating harmonics in the entire frequency range. As an example, the flat-top modulation is examined more detailed. The method is based on the fact that the converter's spectrum is known, for which a calculation approach is presented. The method discussed enables a filter design meeting all requirements of the utility companies concerning voltage quality for all relevant operating ranges. In general, it is suitable for all converter topologies and modulation methods generating periodical output voltages. (orig.)
Lehtinen, B.; Geyser, L. C.
1984-01-01
AESOP is a computer program for use in designing feedback controls and state estimators for linear multivariable systems. AESOP is meant to be used in an interactive manner. Each design task that the program performs is assigned a "function" number. The user accesses these functions either (1) by inputting a list of desired function numbers or (2) by inputting a single function number. In the latter case the choice of the function will in general depend on the results obtained by the previously executed function. The most important of the AESOP functions are those that design,linear quadratic regulators and Kalman filters. The user interacts with the program when using these design functions by inputting design weighting parameters and by viewing graphic displays of designed system responses. Supporting functions are provided that obtain system transient and frequency responses, transfer functions, and covariance matrices. The program can also compute open-loop system information such as stability (eigenvalues), eigenvectors, controllability, and observability. The program is written in ANSI-66 FORTRAN for use on an IBM 3033 using TSS 370. Descriptions of all subroutines and results of two test cases are included in the appendixes.
Characterization of a Dielectric E-Plane Loaded Waveguide by the NMVF: Application to Filters Design
Lilonga-Boyenga, Desire; Okoumou Moko, Gilbert
The rectangular E-plane dielectric loaded metallic waveguide equivalent circuit with dielectric of an arbitrary shape, occupying all height of the waveguide is established using the New Multimodal Variational Formulation (NMVF). The advantage of this rigorous approach compared to the traditional multimodal variational formulation lies in the taking into account of all higher-order modes of the intermediate waveguides in the calculation of the overall structure's impedance matrix Z, thus resulting in increasing the results accuracy and decreasing the computing time. This new passive microwave components analysis and aided-design tool is applied firstly to analyze a rectangular loaded waveguide with one and two centered cylindrical dielectric posts and then one section transformer dielectric phase shifter and secondly, to design an evanescent dielectric resonators band-pass filter in X-band. The results obtained are in good agreement with literature data and FEM software simulations.
Directory of Open Access Journals (Sweden)
Guanquan Liang
2011-12-01
Full Text Available A prototype of planar silicon photonic structure is designed and simulated to provide narrow resonant line-width (∼2 nm in a wide photonic band gap (∼210 nm with broad tunable resonant wavelength range (∼100 nm around the optical communication wavelength 1550 nm. This prototype is based on the combination of two modified basic photonic structures, i.e. a split tapered photonic crystal micro-cavity embedded in a photonic wire waveguide, and a slot waveguide with narrowed slabs. This prototype is then further integrated with a MEMS (microelectromechanical systems based electrostatic comb actuator to achieve “coarse tune” and “fine tune” at the same time for wide range and narrow-band filtering and modulating. It also provides a wide range tunability to achieve the designed resonance even fabrication imperfection occurs.
International Nuclear Information System (INIS)
This paper involves the feasibility of boron neutron capture therapy (BNCT) for liver tumor with four sealed neutron generators as neutron source. Two generators are placed on each side of the liver. The high energy of these emitted neutrons should be reduced by designing a beam shaping assembly (BSA) to make them useable for BNCT. However, the neutron flux decreases as neutrons pass through different materials of BSA. Therefore, it is essential to find ways to increase the neutron flux. In this paper, the feasibility of using low enrichment uranium as a neutron multiplier is investigated to increase the number of neutrons emitted from D-T neutron generators. The neutron spectrum related to our system has a proper epithermal flux, and the fast and thermal neutron fluxes comply with the IAEA recommended values. - Highlights: • The feasibility of sealed neutron generator as neutron source for liver BNCT. • Using natural uranium and low enrichment uranium as neutron multiplier for D–T generator is examined. • A beam shaping assembly is designed to optimize the output neutron beam. • The output of the assembly can fulfill the beam port recommended quality parameters by IAEA
International Nuclear Information System (INIS)
Large diameter groundwater/oil recovery wells were installed in an unconfined sand aquifer at the Ninth Avenue Superfund Site in Gary, Indiana. To assure adequate filter packs, prefilter packed groundwater/oil recovery wells were selected to minimize silting by using appropriate screen slot size and filter pack. A properly sized filter pack was necessary to prevent the formation material from entering the well. During field drilling operations, open-quotes having sandsclose quotes and silting of existing wells were encountered. By using sieve analyses of the native aquifer soil, described by Driscoll (1989), the filter pack and screen slot size were selected. Prefilter packed well screens were selected for this site to assure the presence of a uniform filter pack, thus minimizing siltation in the wells. A prefilter packed well screen consists of a double screen with the interstitial space filled with granular filter pack material designed specifically for site conditions. These wells provide the adequate filter pack without the need to add additional filter pack material outside the well screen. Wells were installed using 12 1/4 inch ID hollow stem augers. This methodology is EPA-approved, expeditious, and inexpensive. Level B personal protective equipment was required during installation. Therefore, the advantages of hollow stem drilling include short drilling time and no circulation fluids. The 14 recovery wells were successfully installed in 14 days using the hollow stem auger drilling technique. Observations during well development revealed little or no silt present in purged groundwater
Hendrix, Charles D.; Vijaya Kumar, B. V. K.
1994-06-01
Correlation filters with three transmittance levels (+1, 0, and -1) are of interest in optical pattern recognition because they can be implemented on available spatial light modulators and because the zero level allows us to include a region of support (ROS). The ROS can provide additional control over the filter's noise tolerance and peak sharpness. A new algorithm based on optimizing a compromise average performance measure (CAPM) is proposed for designing three-level composite filters. The performance of this algorithm is compared to other three-level composite filter designs using a common image database and using figures of merit such as the Fisher ratio, error rate, and light efficiency. It is shown that the CAPM algorithm yields better results.
Directory of Open Access Journals (Sweden)
G.O. Jijina
2014-12-01
Full Text Available This study presents an architectural approach to the design of Low power and area efficient reconfigurable Finite Impulse Response (FIR filter. FIR digital filters are used in DSP by the virtue of its, linear phase, fewer finite precision error, stability and efficient implementation. The proposed architectures implemented by using carry save adder, it offer Low power and area reductions and compared to the best existing reconfigurable FIR filter implementations in the literature and the proposed architectures have been implemented and tested on Spartan-3 xc3s200-5pq208 Field-Programmable Gate Array (FPGA and synthesized.
Directory of Open Access Journals (Sweden)
Mehdi Karimiyan
2011-01-01
Full Text Available In this paper, in order to overcome the coupling and fabrication constraints of microstrip structures, 3 layer stripline structure be introduced and based on impedance steps and microwave coupled lines as impedance inverters and multi mode resonators, new and miniaturized structures are proposed. Using this structure, several 2-6 GHz wideband filters has been designed and simulated, and some effective techniques to reducing virtual resonances and improving slope of filter introduced. Finally, a wideband filter is fabricated and using simulation and measurement, efficiency of method is shown.
INEL BNCT Research Program Annual Report 1993
Energy Technology Data Exchange (ETDEWEB)
Venhuizen, J.R.
1994-08-01
This report is a summary of the progress and research produced for the Idaho National Engineering Laboratory Boron Neutron Capture Therapy Research Program for calendar year 1993. Contributions from all the principal investigators are included, covering chemistry (pituitary tumor studies, boron drug development including liposomes, lipoproteins, and carboranylalanine derivatives), pharmacology (murine screenings, toxicity testing, boron drug analysis), physics (radiation dosimetry software, neutron beam and filter design, neutron beam measurement dosimetry), and radiation biology (tissue and efficacy studies of small and large animal models). Information on the potential toxicity of borocaptate sodium and boronophenylalanine is presented. Results of 21 spontaneous-tumor-bearing dogs that have been treated with boron neutron capture therapy at the Brookhaven National Laboratory are updated. Boron-containing drug purity verification is discussed in some detail. Advances in magnetic resonance imaging of boron in vivo are discussed. Several boron-carrying drugs exhibiting good tumor uptake are described. Significant progress in the potential of treating pituitary tumors is presented. Measurement of the epithermal-neutron flux of the Petten (The Netherlands) High Flux Reactor beam (HFB11B), and comparison to predictions are shown.
Grevillot, L.; Stock, M.; Vatnitsky, S.
2015-10-01
This study aims at selecting and evaluating a ripple filter design compatible with non-isocentric proton and carbon ion scanning beam treatment delivery for a compact nozzle. The use of non-isocentric treatments when the patient is shifted as close as possible towards the nozzle exit allows for a reduction in the air gap and thus an improvement in the quality of scanning proton beam treatment delivery. Reducing the air gap is less important for scanning carbon ions, but ripple filters are still necessary for scanning carbon ion beams to reduce the number of energy steps required to deliver homogeneous SOBP. The proper selection of ripple filters also allows a reduction in the possible transverse and depth-dose inhomogeneities that could appear in non-isocentric conditions in particular. A thorough review of existing ripple filter designs over the past 16 years is performed and a design for non-isocentric treatment delivery is presented. A unique ripple filter quality index (QIRiFi) independent of the particle type and energy and representative of the ratio between energy modulation and induced scattering is proposed. The Bragg peak width evaluated at the 80% dose level (BPW80) is proposed to relate the energy modulation of the delivered Bragg peaks and the energy layer step size allowing the production of homogeneous SOBP. Gate/Geant4 Monte Carlo simulations have been validated for carbon ion and ripple filter simulations based on measurements performed at CNAO and subsequently used for a detailed analysis of the proposed ripple filter design. A combination of two ripple filters in a series has been validated for non-isocentric delivery and did not show significant transverse and depth-dose inhomogeneities. Non-isocentric conditions allow a significant reduction in the spot size at the patient entrance (up to 350% and 200% for protons and carbon ions with range shifter, respectively), and therefore in the lateral penumbra in the patients.
International Nuclear Information System (INIS)
This study aims at selecting and evaluating a ripple filter design compatible with non-isocentric proton and carbon ion scanning beam treatment delivery for a compact nozzle. The use of non-isocentric treatments when the patient is shifted as close as possible towards the nozzle exit allows for a reduction in the air gap and thus an improvement in the quality of scanning proton beam treatment delivery. Reducing the air gap is less important for scanning carbon ions, but ripple filters are still necessary for scanning carbon ion beams to reduce the number of energy steps required to deliver homogeneous SOBP. The proper selection of ripple filters also allows a reduction in the possible transverse and depth-dose inhomogeneities that could appear in non-isocentric conditions in particular.A thorough review of existing ripple filter designs over the past 16 years is performed and a design for non-isocentric treatment delivery is presented. A unique ripple filter quality index (QIRiFi) independent of the particle type and energy and representative of the ratio between energy modulation and induced scattering is proposed. The Bragg peak width evaluated at the 80% dose level (BPW80) is proposed to relate the energy modulation of the delivered Bragg peaks and the energy layer step size allowing the production of homogeneous SOBP. Gate/Geant4 Monte Carlo simulations have been validated for carbon ion and ripple filter simulations based on measurements performed at CNAO and subsequently used for a detailed analysis of the proposed ripple filter design.A combination of two ripple filters in a series has been validated for non-isocentric delivery and did not show significant transverse and depth-dose inhomogeneities. Non-isocentric conditions allow a significant reduction in the spot size at the patient entrance (up to 350% and 200% for protons and carbon ions with range shifter, respectively), and therefore in the lateral penumbra in the patients. (paper)
Energy Technology Data Exchange (ETDEWEB)
Andrea Monti Hughes; Emiliano C.C. Pozzi; Elisa M. Heber; Silvia Thorp; Marcelo Miller; Maria E. Itoiz; Romina F. Aromando; Ana J. Molinari; Marcela A. Garabalino; David W. Nigg; Veronica A. Trivillin; Amanda E. Schwint
2011-11-01
Given the clinical relevance of locoregional recurrences in head and neck cancer, we developed a novel experimental model of premalignant tissue in the hamster cheek pouch for long-term studies and demonstrated the partial inhibitory effect of a single application of Boron Neutron Capture Therapy (BNCT) on tumor development from premalignant tissue. The aim of the present study was to evaluate the effect of a double application of BNCT with a 6 week interval in terms of inhibitory effect on tumor development, toxicity and DNA synthesis. We performed a double application, 6 weeks apart, of (1) BNCT mediated by boronophenylalanine (BPA-BNCT); (2) BNCT mediated by the combined application of decahydrodecaborate (GB-10) and BPA [(GB-10 + BPA)-BNCT] or (3) beam-only, at RA-3 nuclear reactor and followed the animals for 8 months. The control group was cancerized and sham-irradiated. BPA-BNCT, (GB- 10 + BPA)-BNCT and beam-only induced a reduction in tumor development from premalignant tissue that persisted until 8, 3, and 2 months respectively. An early maximum inhibition of 100% was observed for all 3 protocols. No normal tissue radiotoxicity was detected. Reversible mucositis was observed in premalignant tissue, peaking at 1 week and resolving by the third week after each irradiation. Mucositis after the second application was not exacerbated by the first application. DNA synthesis was significantly reduced in premalignant tissue 8 months post-BNCT. A double application of BPA-BNCT and (GB-10 + BPA)-BNCT, 6 weeks apart, could be used therapeutically at no additional cost in terms of radiotoxicity in normal and dose-limiting tissues.
International Nuclear Information System (INIS)
Given the clinical relevance of locoregional recurrences in head and neck cancer, we developed a novel experimental model of premalignant tissue in the hamster cheek pouch for long-term studies and demonstrated the partial inhibitory effect of a single application of Boron Neutron Capture Therapy (BNCT) on tumor development from premalignant tissue. The aim of the present study was to evaluate the effect of a double application of BNCT with a 6 week interval in terms of inhibitory effect on tumor development, toxicity and DNA synthesis. We performed a double application, 6 weeks apart, of (1) BNCT mediated by boronophenylalanine (BPA-BNCT); (2) BNCT mediated by the combined application of decahydrodecaborate (GB-10) and BPA ((GB-10 + BPA)-BNCT) or (3) beam-only, at RA-3 nuclear reactor and followed the animals for 8 months. The control group was cancerized and sham-irradiated. BPA-BNCT, (GB- 10 + BPA)-BNCT and beam-only induced a reduction in tumor development from premalignant tissue that persisted until 8, 3, and 2 months respectively. An early maximum inhibition of 100% was observed for all 3 protocols. No normal tissue radiotoxicity was detected. Reversible mucositis was observed in premalignant tissue, peaking at 1 week and resolving by the third week after each irradiation. Mucositis after the second application was not exacerbated by the first application. DNA synthesis was significantly reduced in premalignant tissue 8 months post-BNCT. A double application of BPA-BNCT and (GB-10 + BPA)-BNCT, 6 weeks apart, could be used therapeutically at no additional cost in terms of radiotoxicity in normal and dose-limiting tissues.
9Be(d,n)10B-based neutron sources for BNCT
International Nuclear Information System (INIS)
In the frame of accelerator-based BNCT, the 9Be(d,n)10B reaction was investigated as a possible source of epithermal neutrons. In order to determine the configuration in terms of bombarding energy, target thickness and Beam Shaping Assembly (BSA) design that results in the best possible beam quality, a systematic optimization study was carried out. From this study, the optimal configuration resulted in tumor doses ≥40 Gy-Eq, with a maximum value of 51 Gy-Eq at a depth of about 2.7 cm, in a 60 min treatment. The optimal configuration was considered for the treatment planning assessment of a real Glioblastoma Multiforme case. From this, the resulted dose performances were comparable to those obtained with an optimized 7Li(p,n)-based neutron source, under identical conditions and subjected to the same clinical protocol. - Highlights: • Study of the 9Be(d,n)10B reaction as a source of epithermal neutrons for BNCT. • Evaluation of the optimal configuration of target thickness, deuteron energy and BSA design. • Computational dose assessment for brain tumor treatments using the MCNP code. • Treatment planning assessment of a particular clinical Glioblastoma Multiforme case. • Dose performances were comparable to those obtained with an optimized 7Li(p,n)-based source
Dose-rate scaling factor estimation of THOR BNCT test beam
International Nuclear Information System (INIS)
In 1998, an epithermal neutron test beam was designed and constructed at the Tsing Hua Open-Pool Reactor (THOR) for the purpose of preliminary dosimetric experiments in boron neutron capture therapy (BNCT). A new epithermal neutron beam was designed at this facility, and is currently under construction, with clinical trials targeted in late 2004. Depth dose-rate distributions for the THOR BNCT test beam have been measured by means of activation foil and dual ion chamber techniques. Neutron and structure-induced gamma spectra measured at the test beam exit were configured into a source function for the Monte Carlo-based treatment planning code NCTPlan. Dose-rate scaling factors (DRSFs) were determined to normalize computationally derived dose-rate distributions with experimental measurements in corresponding mathematical and physical phantoms, and to thus enable accurate treatment planning using the NCTPlan code. A similar approach will be implemented in characterizing the new THOR epithermal beam in preparation for clinical studies. This paper reports the in-phantom calculated and experimental dosimetry comparisons and derived DRSFs obtained with the THOR test beam
In vivo BNCT in experimental and spontaneous tumors at RA-1 reactor
International Nuclear Information System (INIS)
Within the search for new applications of Boron Neutron Capture Therapy (BNCT) and the basic research oriented towards the study of BNCT radiobiology to optimize its therapeutic gain, we previously proposed and validated the hamster cheek pouch oral cancer model and showed, for the first time, the success of BNCT to treat oral cancer in an experimental model. The staff of the Ra-1 Reactor (Constituyentes Atomic Center) adapted the thermal beam and physical set-up to perform in vivo BNCT of superficial tumors in small animals. We preformed a preliminary characterization of the thermal beam, performed beam only irradiation of normal and tumor bearing hamsters and in vivo BNCT of experimental oral squamous cell carcinomas in hamsters mediated by boron phenylalanine (BPA) and GB-10 (Na210B10H10). Having demonstrated the absence of radio toxic effects in healthy tissue and a therapeutic effect of in vivo BNCT in hamster cheek pouch tumors employing the Ra-1 thermal beam, we performed a feasibility study of the treatment by BNCT of 3 terminal cases of spontaneous head and neck squamous cell carcinoma in cats following the corresponding biodistribution studies. This was the first treatment of spontaneous tumors by BNCT in our country and the first treatment by BNCT in cats worldwide. This preclinical study in terminal cases showed significant tumor control by BNCT with no damage to normal tissue. (author)
FPGA Design and Implementation of Multi-Filtering Techniques Using Flag-Bit and Flicker Clock
Directory of Open Access Journals (Sweden)
M. H. Al-Doori
2012-07-01
Full Text Available Real time system is a condition where the processor is required to perform its tasks within a certain time constraints of some processes or simultaneously with the system it is assisting. Typically, it suffers from two main problems; delay in data processing and complexity of the decision-making process. The delay is caused by reasons such as computational power, processor unit architecture, and synchronization signals in the system. To improve the performance of these systems in term of processing power, a new architecture and clocking technique is realized in this paper. This new architecture design called Embedded Parallel Systolic Filters (EPSF that process data gathered from sensors and landmarks are proposed in our study using a high-density reconfigurable device (FPGA chip. The results expose that EPSF architecture and bit-flag with a flicker clock achieve appreciably better in multiple input sensors signal under both incessant and interrupted conditions. Unlike the usual processing units in current tracking and navigation systems used in robots, this system permits autonomous control of the robot through a multiple technique of filtering and processing. Furthermore, it offers fast performance and a minimal size for the entire system that minimizing the delay about 50%.
O'Callaghan, Finbarr; O'Brien, Stephen
2014-01-01
We consider design optimization of passively mode-locked two-section semiconductor lasers that incorporate intracavity grating spectral filters. Our goal is to develop a method for finding the optimal wavelength location for the filter in order to maximize the region of stable mode-locking as a function of drive current and reverse bias in the absorber section. In order to account for material dispersion in the two sections of the laser, we use analytic approximations for the gain and absorption as a function of carrier density and frequency. Fits to measured gain and absorption curves then provide inputs for numerical simulations based on a large signal accurate delay-differential model of the mode-locked laser. We show how a unique set of model parameters for each value of the drive current and reverse bias voltage can be selected based on the variation of the net gain along branches of steady-state solutions of the model. We demonstrate the validity of this approach by demonstrating qualitative agreement b...
Design of jitter compensation algorithm for robot vision based on optical flow and Kalman filter.
Wang, B R; Jin, Y L; Shao, D L; Xu, Y
2014-01-01
Image jitters occur in the video of the autonomous robot moving on bricks road, which will reduce robot operation precision based on vision. In order to compensate the image jitters, the affine transformation kinematics were established for obtaining the six image motion parameters. The feature point pair detecting method was designed based on Eigen-value of the feature windows gradient matrix, and the motion parameters equation was solved using the least square method and the matching point pairs got based on the optical flow. The condition number of coefficient matrix was proposed to quantificationally analyse the effect of matching errors on parameters solving errors. Kalman filter was adopted to smooth image motion parameters. Computing cases show that more point pairs are beneficial for getting more precise motion parameters. The integrated jitters compensation software was developed with feature points detecting in subwindow. And practical experiments were conducted on two mobile robots. Results show that the compensation costing time is less than frame sample time and Kalman filter is valid for robot vision jitters compensation. PMID:24600320
RF MEMS and CSRRs-based tunable filter designed for Ku and K bands application
Directory of Open Access Journals (Sweden)
Ngasepam Monica Devi
2015-12-01
Full Text Available This paper presents the design and simulation of a reconfigurable stop-band filter on a silicon substrate based on the combination of RF microelectromechanical system and metamaterial-based technologies. The device is implemented on coplanar waveguide structure by embedding complementary split-ring resonators on the central line and an RF MEMS varactor bridge supporting the neighboring ground planes. The response characteristics of this metamaterial-based filter can be dynamically tuned, thus enhancing its usefulness. The device operates within a frequency range of 16.5–19.5 GHz, giving a tuning range of 15%, and can be tuned from Ku-frequency band to K-frequency band. It works with a comparative low pull-in voltage of 17.42 V and a faster switching time of 0.138 µs. A thorough electromechanical analysis has been done by varying various structural and material parameters. Moreover, a comparative electrical performance of silicon and glass has been shown to overcome the cons of silicon by high-resistivity glass.
INEL BNCT Program: Volume 5, No. 9. Bulletin, September 1991
Energy Technology Data Exchange (ETDEWEB)
Ackermann, A.L. [ed.
1991-12-31
This Bulletin presents a summary of accomplishments and highlights of the Idaho National Engineering Laboratory`s (INEL) Boron Neutron Capture Therapy (BNCT) Program for September 1991. This bulletin includes information on the brain tumor and melanoma research programs, Power Burst Facility (PBF) technical support and modifications, PBF operations, and updates to the animal data charts.
Energy Technology Data Exchange (ETDEWEB)
Xiao, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Belomestnykh, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States); Ben-Zvi, I. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States); Burt, G. [Lancaster Univ. (United Kingdom); Calaga, R. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Capatina, O. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Hall, B. [Lancaster Univ. (United Kingdom); Jones, T. [Science and Technology Facilities Council (STFC), Daresbury (United Kingdom). Daresbury Lab.; Skaritka, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Verdu-Andres, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wu, Q. [Brookhaven National Lab. (BNL), Upton, NY (United States)
2015-05-03
A Double Quarter Wave Crab Cavity (DQWCC) was designed for the Large Hadron Collider (LHC) luminosity upgrade. A compact Higher Order Mode (HOM) filter with wide stop band at the deflecting mode is developed for this cavity. Multiphysics finite element simulation results are presented. The integration of this design to the cavity cryomodule is described.
Xiao, B P; Ben-Zv, I; Burt, Graeme Campbell; Calaga, Rama; Capatina, Ofelia; Hall, B; Jones, T; Skaritka, J; Verdú-Andrés, S; Wu, Q
2015-01-01
A Double Quarter Wave Crab Cavity (DQWCC) was designed for the Large Hadron Collider (LHC) luminosity upgrade. A compact Higher Order Mode (HOM) filter with wide stop band at the deflecting mode is developed for this cavity. Multi-physics finite element simulation results are presented. The integration of this design to the cavity cryomodule is described.
Kuldeep, B; Singh, V K; Kumar, A; Singh, G K
2015-01-01
In this article, a novel approach for 2-channel linear phase quadrature mirror filter (QMF) bank design based on a hybrid of gradient based optimization and optimization of fractional derivative constraints is introduced. For the purpose of this work, recently proposed nature inspired optimization techniques such as cuckoo search (CS), modified cuckoo search (MCS) and wind driven optimization (WDO) are explored for the design of QMF bank. 2-Channel QMF is also designed with particle swarm optimization (PSO) and artificial bee colony (ABC) nature inspired optimization techniques. The design problem is formulated in frequency domain as sum of L2 norm of error in passband, stopband and transition band at quadrature frequency. The contribution of this work is the novel hybrid combination of gradient based optimization (Lagrange multiplier method) and nature inspired optimization (CS, MCS, WDO, PSO and ABC) and its usage for optimizing the design problem. Performance of the proposed method is evaluated by passband error (ϕp), stopband error (ϕs), transition band error (ϕt), peak reconstruction error (PRE), stopband attenuation (As) and computational time. The design examples illustrate the ingenuity of the proposed method. Results are also compared with the other existing algorithms, and it was found that the proposed method gives best result in terms of peak reconstruction error and transition band error while it is comparable in terms of passband and stopband error. Results show that the proposed method is successful for both lower and higher order 2-channel QMF bank design. A comparative study of various nature inspired optimization techniques is also presented, and the study singles out CS as a best QMF optimization technique. PMID:25034647
International Nuclear Information System (INIS)
Based on the pre-clinical work of the European Collaboration on Boron Neutron Capture Therapy a study protocol was prepared in 1995 to initiate Boron Neutron Capture Therapy (BNCT) in patients at the High Flux Reactor (HFR) in Petten. Bio-distribution and pharmacokinetics data of the boron drug Na2B12H11SH (BSH) as well as the radiobiological effects of BNCT with BSH in healthy brain tissue of dogs were considered in designing the strategy for this clinical Phase I trial. The primary goal of the radiation dose escalation study is the investigation of possible adverse events due to BNCT; i.e. to establish the dose limiting toxicity and the maximal tolerated dose. The treatment is delivered in 4 fractions at a defined average boron concentration in blood. Cohorts of 10 patients are treated per dose group. The starting dose was set at 80% of the dose at which neurological symptoms occurred in preclinical dog experiments following a single fraction. After an observation period of at least 6 months, the dose is increased by 10% for the next cohort if less then three severe side effects related to the treatment occurred. The results of the first cohort are presented here. The evaluated dose level can be considered safe. (author)
A new design concept for realising highly tunable microwave filters using recursive principles
Mouzannar, W.; Billonnet, L.; Jarry, B.; Guillon, P.
1998-01-01
In this paper, new active monolithic microwave integrated bandpass filters employing recursive principles are developped. A 7 GHz fixed center frequency filter with 2% bandwidth, and a tunable filter with 2.5 GHz tuning range around 8 GHz, are succesfully implemented employing 0.2 um GaAs P-HEMT monolithic technology, and exhibit excellent measured performances.
Validation and Optimization of a Design Formula for Stable Geometrically Open Filter Structures
Van de Sande, S.A.H.; Uijttewaal, W.S.J.; Verheij, H.J.
2014-01-01
Granular filters are used for protection against scour and erosion of base material. For a proper functioning it is necessary that at the interfaces between the filter structure, the subsoil and the water flowing above the filter structure no material will be transported. Different types of granular
Design and operation of optimized high efficiency filter element test systems
International Nuclear Information System (INIS)
This paper discusses significant improvements in the design and operation of high efficiency filter test systems. The major areas discussed are the optimization of system hardware and the application of statistical analysis to expedite the test procedure. This has resulted in systems which can verify HEPA performance in 15 seconds, ULPA performance in 60 seconds, with low mass loading of non-DOP aerosols. Performance data are presented for two systems spanning a flow rate range of 1 to 65 m/sub 3//min (30 to 2000 cfm) and capable of determining fractional penetrations down to 10/sup -7/ (efficiencies up to 99.99999%) for particles from 0.1 to 1.0 micrometers
The Finnish Boron neutron capture therapy (BNCT) project
International Nuclear Information System (INIS)
Boron neutron capture therapy (BNCT) is a new, binary radiotherapy, which has been developed especially for severe brain tumours, incurable by the present means. A suitable 10B containing carrier compound is injected into the blood circulation and taken up selectively by the cancer cells. When these cells are subjected to a thermal neutron field, the 10B atoms capture the neutrons and undergo fission reaction. The energy thereby released is killing the cancerous cell. The Finnish BNCT research and development project is in the situation where all the basic conditions exist to start clinical trials. An epithermal neutron irradiation facility has been constructed at the Finnish research reactor (FiR 1) operated by VTT in Otaniemi. This article is an overview over the developments within the Finnish BNCT project. A research project to carry out clinical application of BNCT was established in Finland in the early 1990's. It was motivated both by the need to create new uses for FiR 1 and by the ideas to start research and production of new boron carriers for BNCT in Finland. Soon also other medical, medical physics and chemistry disciplines joined the project. Now the project involves scientists from different departments of University of Helsinki (HU), Helsinki University Central Hospital (HUCH), Technical Research Centre of Finland (VTT), Finnish Radiation and Nuclear Safety Authority (STUK) and of the Helsinki University of Technology (HUT) and other Finnish universities. The aim of this project has been to start BNC-treatment of malignant brain tumours in Finland by the end of the century
International Nuclear Information System (INIS)
As part of the European Commission's Enlargement and Integration Action (E and IA), which is intended to improve exchange and relationship within the extended European Union (EU), a Workshop was organized in Prague in November 2005. The purpose of the workshop was to present and discuss technical and organisational requirements in setting up a BNCT facility at a research reactor. Topics included: treatment of a patient by BNCT; organisational aspects and regulatory affairs; BNCT from the nuclear perspective and BNCT from the clinician's perspective. Presentations were given by BNCT experts in their particular field, whilst eleven different national nuclear research centres from the New Member States and Accession Countries, interested in developing a BNCT programme, presented the status of their preparations. The conclusions of the Workshop were that an early and close collaboration between nuclear and medical groups is the basis for BNCT, that a local effort to build a BNCT facility should be supported by a national research programme including basic and clinical science and that the JRC and its partners are ready to support national initiatives within the EU and candidate countries. (author)
Flat-top MZI filters: a novel robust design based on MMI splitters
Cherchi, Matteo; Harjanne, Mikko; Ylinen, Sami; Kapulainen, Markku; Vehmas, Tapani; Aalto, Timo
2016-03-01
Multimode Interferometers (MMIs) are an attractive alternative to directional couplers, ensuring more relaxed tolerances to fabrication errors and broader operation bandwidth. The drawback is that only a limited discrete set of splitting ratios is achievable with MMIs of constant cross section. This issue clearly limits their use in flat-top interferometric filters, which design requires, in general, free choice of the splitting ratios. Here we show for the first time that it is possible to design 4-stage flat-top interferometers using only standard MMIs with 50:50 and 85:15 splitting ratios. The design approach is based on the representation of the system on the Bloch sphere. Flat-top interleavers with different free spectral ranges have been designed and fabricated on the silicon photonics platform of VTT, based on 3 μm thick rib and strip waveguides. Two different layouts have been explored: one where all components are collinear and a more compact one which elements have been folded in a spiral shape. All interleavers have been designed for TE polarization, and they work in a wavelength range comparable with the 100 nm bandwidth of the MMI splitters. Even though fabrication imperfections and non-ideal behaviour of both waveguide bends and MMIs led to reduced extinction compared to simulations, most devices show in-band extinction exceeding 15 dB. The in-band losses of the most central channels did not exceed 1.5 dB compared to the reference straight waveguide. The designed interleavers can be employed in cascaded configurations to achieve broadband and fabrication tolerant flat-top wavelength (de)multiplexers.
International Nuclear Information System (INIS)
High energy proton beam (>8 MeV) is favorable for producing neutrons with high yield. However, the produced neutrons are of high energies. These high energy neutrons can cause severe fast neutron contamination and degrade the BNCT treatment quality if they are not appropriately moderated. Hence, this study aims to briefly discuss the issue, from the viewpoint of fast neutron contamination control, whether high energy proton beam is ideal for AB-BNCT or not. In this study, D2O, PbF4, CaF2, and Fluental™ were used standalone as moderator materials to slow down 1-, 6-, and 10-MeV parallelly incident neutrons. From the calculated results, we concluded that neutrons produced by high energy proton beam could not be easily moderated by a single moderator to an acceptable contamination level and still with reasonable epithermal neutron beam intensity. Hence, much more complicated and sophisticated designs of beam shaping assembly have to be developed when using high energy proton beams. - Highlights: • The fast neutron contamination profiles of 3 different moderator materials were discussed. • D2O, PbF4 and Fluental™ were tested as standalone moderators. • Standalone moderator cannot effectively suppress fast neutrons higher than 1 MeV. • AB-BNCT by high energy proton beam suffers serious fast neutron contamination. • The use of high energy protons (>8 MeV) for AB-BNCT should be carefully evaluated
International Nuclear Information System (INIS)
Highlights: ► A rigorous systematic design process based on circuit synthesis is proposed for band-stop filters. ► The new compact E-plane waveguide structure reduces drastically the unwanted resonances in a very large pass band. ► The manufacturing process together with the computation effort is significantly reduced. ► Experimental results validate the state-of-art electrical responses. - Abstract: Band-stop or notch filters play a crucial role in plasma diagnosis systems to protect receivers from the stray radiation. In this work, a rigorous design process based on circuit synthesis in addition to an extremely compact E-plane waveguide structure is proposed for this kind of filters. On the one hand, the transfer function verifying the rejection specification is analytically obtained, fixing the minimum number of required cavities. On the other hand, a coupling structure that reduces drastically the unwanted resonances in filters with a very large pass band requirement, is presented. This coupling between the rejection cavities and the main rectangular waveguide has additional advantages; (a) unlike typical inductive irises, large coupling coefficients can be implemented (b) a pure E-plane configuration is achieved, which simplifies the manufacturing and also reduces significantly the computational effort. Experimental validation is demonstrated by two pseudo-elliptic fifth-order band-stop filters fabricated and measured in Ka and V bands. In both cases, the filters are free of spurious resonances in their total operation bands.
Energy Technology Data Exchange (ETDEWEB)
Lee, Seunguk; Park, Minchan; Lee, Jaekeun [EcoEnergy Research Institute, Busan (Korea, Republic of)
2014-05-15
In the U. S., the number of HEPA filters, which are located in the HVAC system of nuclear power plants, generated as wastes is annually 31,055, and tremendous economic/social costs are incurred to deal with them. Thus, it is needed to develop the metal fiber filter that can be reused and has performance equal to the HEPA level to replace the glass fiber HEPA filter. This study, to draw the optimal design factors of the metal fiber filter for removing radioactive aerosol, analyzed the design condition by reflecting the actual temperature and pressure condition that can be generated in the nuclear HVAC system to the particle collection mechanism by single fiber. As a result of performing modeling for the radioactive aerosol particle collection efficiency and the pressure drop of the filter made up with single metal fiber. It was analyzed that when a diameter of the metal fiber is less than 4 μm, thickness more than 1 mm, solidity more than 0.2, and face velocity less than 5 cm, it shows more than 99.97% particle collection efficiency, which is equal to the HEPA level. Because generally as the particle collection efficiency gets higher, the pressure drop gets bigger, it is judged that the filter design factors should be optimized to satisfy the design condition for the HVAC system. It is also judged that, in the future, an additional verification should be conducted through a comparison of the test results of the filter particle collection efficiency and the pressure drop in the condition of actual temperature and pressure, and the modeling results of this study.
Shinde, Sudarshan
2010-01-01
In this paper we present a method to design paraunitary polyphase matrices of critically sampled rational filter banks. The method is based on (P,Q) shift-invariant systems, and so any kind of rational splitting of the frequency spectrum can be achieved using this method. Ideal (P,Q) shift-invariant system with smallest P and Q that map of a band of input spectrum to the output spectrum are obtained. A new set of filters is obtained that characterize a (P,Q) shift-invariant system. Ideal frequency spectrum of these filters are obtained using ideal $(P,Q)$ shift-invariant systems. Actual paraunitary polyphase matrices are then obtained by minimizing the stopband energies of these filters against the parameters of the paraunitary polyphase matrices.
A phase-I clinical trial for cranial BNCT at Harvard-MIT
International Nuclear Information System (INIS)
Phase I trial designed to determine the maximum tolerable dose to normal tissue for cranial BNCT (Boron Neutron Capture Therapy) irradiations was recently completed at Harvard Medical School and MIT. Twenty-two subjects diagnosed with either glioblastoma multiforme or intracranial melanoma were treated between 1996 and 1999. Subjects received either one or two administrations of boronophenylalanine intravenously at doses between 250 and 350 mg/kg body weight, then exposed in one, two or three fields to epithermal neutrons at the MIT Research Reactor in one or two fractions. Over the course of the study, the maximum normal tissue dose target was increased from 8.8 to 14.2 RBE (Relative Biological Effectiveness) Gy in 10% increments. Subjects have been followed clinically and radiographically. Of those patients surviving beyond six months, no MRI (Magnetic Resonance Image) white-matter changes were observed and no long-term complications attributable to BNCT were evident. Tumor responses were observed, particularly with the melanoma subjects. With increasing doses, difficulties arose from long irradiation times (approximately 3 hours) and the emergence of acute reactions in the skin and mucosa. The trial was stopped in May 1999. Future trials will be initiated with the new high intensity, low background fission converter beam at MIT. (author)
Energy Technology Data Exchange (ETDEWEB)
Monti Hughes, A.; Heber, E.M. [Department of Radiobiology, National Atomic Energy Commission (CNEA), Buenos Aires (Argentina); Pozzi, E. [Department of Radiobiology, National Atomic Energy Commission (CNEA), Buenos Aires (Argentina); Department of Research and Production Reactors, Ezeiza Atomic Center, CNEA, Buenos Aires (Argentina); Nigg, D.W. [Idaho National Laboratory, Idaho Falls, Idaho (United States); Calzetta, O.; Blaumann, H.; Longhino, J. [Department of Nuclear Engineering, Bariloche Atomic Center, CNEA, Rio Negro (Argentina); Nievas, S.I. [Department of Chemistry, CNEA, Buenos Aires (Argentina); Aromando, R.F. [Department of Oral Pathology, Faculty of Dentistry, University of Buenos Aires, Buenos Aires (Argentina); Itoiz, M.E. [Department of Radiobiology, National Atomic Energy Commission (CNEA), Buenos Aires (Argentina); Department of Oral Pathology, Faculty of Dentistry, University of Buenos Aires, Buenos Aires (Argentina); Trivillin, V.A. [Department of Radiobiology, National Atomic Energy Commission (CNEA), Buenos Aires (Argentina); Schwint, A.E. [Department of Radiobiology, National Atomic Energy Commission (CNEA), Buenos Aires (Argentina)], E-mail: schwint@cnea.gov.ar
2009-07-15
We previously demonstrated the efficacy of boron neutron capture therapy (BNCT) mediated by boronophenylalanine (BPA), GB-10 (Na{sub 2}{sup 10}B{sub 10}H{sub 10}) and (GB-10+BPA) to control tumors, with no normal tissue radiotoxicity, in the hamster cheek pouch oral cancer model. Herein we developed a novel experimental model of field-cancerization and precancerous lesions (globally termed herein precancerous tissue) in the hamster cheek pouch to explore the long-term potential inhibitory effect of the same BNCT protocols on the development of second primary tumors from precancerous tissue. Clinically, second primary tumor recurrences occur in field-cancerized tissue, causing therapeutic failure. We performed boron biodistribution studies followed by in vivo BNCT studies, with 8 months follow-up. All 3 BNCT protocols induced a statistically significant reduction in tumor development from precancerous tissue, reaching a maximum inhibition of 77-100%. The inhibitory effect of BPA-BNCT and (GB-10+BPA)-BNCT persisted at 51% at the end of follow-up (8 months), whereas for GB-10-BNCT it faded after 2 months. Likewise, beam-only elicited a significant but transient reduction in tumor development. No normal tissue radiotoxicity was observed. At 8 months post-treatment with BPA-BNCT or (GB-10+BPA)-BNCT, the precancerous pouches that did not develop tumors had regained the macroscopic and histological appearance of normal (non-cancerized) pouches. A potential new clinical application of BNCT would lie in its capacity to inhibit local regional recurrences.
Boron Neutron Capture Therapy at the TRIGA Mark II of Pavia, Italy - The BNCT of the diffuse tumours
Energy Technology Data Exchange (ETDEWEB)
Altieri, S.; Bortolussi, S.; Stella, S.; Bruschi, P.; Gadan, M.A. [University of Pavia (Italy); INFN - National Institute for Nuclear Physics, of Pavia (Italy)
2008-10-29
in those samples that cannot be cut into thin slices (bone). The beam and set-up design (MCNP calcs) is underway. Another project concerns the in vivo BNCT irradiating of rats with pulmonary metastases and infused with BPA in the thermal column of the TRIGA reactor. A study is underway to design the shielding and the dose distribution inside the lungs and the radiosensitive organs of the animal. (Simulations by MCNP, construction of a phantom for the n flux measurement by activation method)
International Nuclear Information System (INIS)
Objective: BNCT is a binary treatment modality based on the nuclear reactions that occur when boron (10B) is exposed to thermal neutrons. Preclinical studies have demonstrated the therapeutic efficacy of p-boronophenylalanine (BPA)-based BNCT. The objective of the Phase I/II trial was to evaluate BPA-fructose (BPA-F) as a boron delivery agent for GBM and to study the feasibility and safety of a single-fraction of BNCT. Materials and Methods: The trial design required i) a BPA-F biodistribution study performed at the time of craniotomy; and ii) BNCT within 4 weeks of the craniotomy. From September 94 to July 95, 10 patients with biopsy proven GBM were treated. All but 1 patient underwent a biodistribution study receiving IV BPA-F at the time of craniotomy. Multiple tissue samples and concurrent blood and urine samples were collected for evaluation of the boron concentration and clearance kinetics. For BNCT all patients received 250 mg/kgm of BPA-F (IV infusion over 2 hrs) followed by neutron irradiation. The blood 10B concentration during irradiation was used to calculate the time of neutron exposure. The 3D treatment planning was done using the BNCT treatment planning software developed at the Idaho National Engineering Laboratory. The BNCT dose is expressed as the sum of the physical dose components corrected for both the RBE and the 10B localization factor with the unit Gy-Eq. The photon-equivalent dose, where the thermal neutron fluence reaches a maximum, is the peak-dose equivalent. A single-fraction of BNCT was delivered prescribing 10.5 Gy-Eq (9 patients) and 13.8 Gy-Eq (1 patient) as the peak dose-equivalent to the normal brain. The peak dose rate was kept below 27 cGy-Eq/min. Results: Biodistribution data: The maximum blood 10B concentration was observed at the end of the infusion and scaled as a linear function of the administered dose. The 10B concentration in the scalp and in the GBM tissue was higher than in blood by 1.5 x and at least 3.5 x
Institute of Scientific and Technical Information of China (English)
Abdolreza Esmaeli; SUN Li; ZHAO Ke; JIANG Bao-jun
2005-01-01
EMI Filter Design and Performance for isolated full bridge buck converter is developed in this paper.In order to design a high performance EMI filter, many issues need to be considered beforehand. Some important issues including accurate model of converter components, parasitic elements, its effect on EMI noise and impedance mismatch are included in this paper. A numerical prediction of EMI/EMC has the potential to evaluate EMI performances at the design stage and before prototyping. It can also help reduce the post-prototype EMC cost by minimizing late redesign and modifications of a design implementation. Saber simulator is used to analyze the EMI noises and EMI filter's performance. Conducted EMI noise measurement and EMI filter design of isolated full bridge buck converter has been achieved while successfully satisfying the FCC class B limits in the frequency range from 150 kHz to 30 MHz. Simulation results are compared with experimental data and the effectiveness of the EMI simulation approach is demonstrated.
High-Density EMI Filter Design for DC-Fed Motor Drives
Energy Technology Data Exchange (ETDEWEB)
Lai, Rixin [General Electric; Maillet, Yoann [Virginia Polytechnic Institute and State University (Virginia Tech); Wang, Shuo [ORNL; Wang, Fei [ORNL; Burgos, Rolando [ABB; Boroyevich, Dushan [Virginia Polytechnic Institute and State University (Virginia Tech)
2010-01-01
This paper presents strategies to reduce both differential-mode (DM) and common-mode (CM) noise using a passive filter in a dc-fed motor drive. The paper concentrates on the type of grounding and the components to optimize filter size and performance. Grounding schemes, material comparison between ferrite and nanocrystalline cores, and a new integrated filter structure are presented. The integrated structure maximizes the core window area and increases the leakage inductance by integrating both CM and DM inductances onto one core. Small-signal and large-signal experiments validate the structure, showing it to have reduced filter size and good filtering performance when compared with standard filters at both low and high frequencies.
Design and realization of digital nuclear signal filter shape based on LabVIEW
International Nuclear Information System (INIS)
Background: Digital nuclear signal filter shape is of great importance to the energy resolution and the counting rate in nuclear spectrometer system. Purpose: This paper attempts to achieve transfer function method and the synthesis forming filter shape based on LabVIEW. Methods: The digital nuclear signal which comes from the high speed ADC was formed a certain curvature of the concave and convex shaper in synthesis forming method, simply modify the forming parameters, the different shapes (trapezoid, triangle and gauss) were achieved by this method. Results: Finally, to validate the feasibility and practicability of the filtering methods, with the use of the modification of forming parameters on LabVIEW platform and the call of program in MATLAB, the transfer function and the synthesis forming method were used to complete filter shape. Conclusions: Based on the results, the filtering method can be used to provide technical support for the choices of filter shape schemes and parameters. (authors)
Design and Analysis of Microstrip Multi-Channeled Filter Using Photonic Crystal Branchy Defect
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
A multi-channeled filter based on branchy defect in a microstrip photonic crystal was proposed. By introducing a branchy structure across the defect region, multiple defect modes will appear inside the photonic gap, leading to the multi-channeled filtering phenomenon. In comparison with the conventional multi-channeled filters, the proposed structure is more compact and tunable as far as the device volume and fabrication are concerned. The microwave experiment results are found in agreement with simulation results.
International Nuclear Information System (INIS)
Full text of publication follows: One of the basic performances of aerosol filters is the aerodynamic resistance to the flow of gaseous medium to be cleaned. Calculation of the aerodynamics of aerosol filters in reference to the gas loops of reactor installations with heavy liquid metal coolant (HLMC) allows the design of the structural components of filters to be optimized to provide minimum initial resistance values. It is established that owing to various factors aerosol particles of different concentration and disperse composition are present always in the gas spaces of heavy liquid metal cooled reactor gas loops. To prevent the negative effect of aerosols on the equipment of the gas loops, it is reasonable to use filters of multistep design with sections of preliminary and fine cleaning to catch micron and submicron particles, respectively. A computer program and technique have been developed to evaluate the aerodynamics of folded aerosol filters for different parameters of their structural components, taking account of the aerosol spectrum and concentration. The algorithm of the calculation is presented by the example of a two-step design assembled in single vessel; the filter dimensions and pattern of the air flow to be cleaned are determined under the given boundary conditions. The evaluation of the aerodynamic resistance of filters was performed with consideration for local resistances and resistances of all the structural components of the filter (sudden constriction, expansion, the flow in air channels, filtering material and so on). Correlations have been derived for the resistance of air channels, filtering materials of preliminary and fine cleaning sections as a function of such parameters as the section depth (50-500 mm), the height of separators (3,5-20 mm), the filtering surface area (1,5-30 m2). Based on the calculation results, the auto-similarity domain was brought out for the minimal values of filter resistances as a function of the ratio of
Design of LLCL-filter for grid-connected converter to improve stability and robustness
DEFF Research Database (Denmark)
Huang, Min; Wang, Xiongfei; Loh, Poh Chiang;
2015-01-01
The LLCL-filter has recently emerged into gridconnected converters due to the improved filtering capability which ensuring a smaller physical size. An LLCL -based gridconnected converter has almost the same frequency-response characteristic as that with the traditional LCL-filter within half of the...... example for LLCL-filter is given. Both simulations and experimental results are provided through a 5 kW, 380V/50 Hz grid-connected inverter model to validate the theoretical analysis in this paper....
Directory of Open Access Journals (Sweden)
Abhijit Chandra
2012-10-01
Full Text Available In recent times, system designers are becoming very much apprehensive in reducing the structural complexity of digital systems with which they deal in practice. However, the uncontrolled minimization of any digital hardware always leads to significant deterioration of system performance making it incompatible for use in any practical system. As proper trade-off is inevitably essential between achievable performance and required hardware, researchers have sought a number of artificially intelligent optimization techniques to solve it out. Since such a technique generally involves variety of constructional alternatives, appropriate use of correct option demands justified attention. Numerous evolutionary computation techniques, being a branch of biologically inspired optimization process, are being increasingly used for a number of signal processing applications of late. This paper throws enough light to select the most suitable mutation strategy of Differential Evolution (DE algorithm for efficient design of multiplier-less low-pass finite duration impulse response (FIR filter. Computationally efficient mutation scheme has been identified by observing convergence behavior and error histogram plot for different alternatives. Performance of the designed filter has been compared in terms of its magnitude response and the requirement of various hardware blocks for four different lengths of the filter. Consequently the name of the most favorable mutation rule has been suggested upon analyzing all the factors. Finally the supremacy of our proposed design has been established by comparing its performance with that of other state-of-the-art multiplier-less low-pass FIR filters.
Treatment Planning Systems for BNCT Requirements and Peculiarities
Daquino, G G
2003-01-01
The main requirements and peculiarities expected from the BNCT-oriented treatment planning system (TPS) are summarized in this paper. The TPS is a software, which can be integrated or composed by several auxiliary programs. It plays important roles inside the whole treatment planning of the patient's organ in BNCT. However, the main goal is the simulation of the irradiation, in order to obtain the optimal configuration, in terms of neutron spectrum, patient positioning and dose distribution in the tumour and healthy tissues. The presence of neutrons increases the level of complexity, because much more nuclear reactions need to be monitored and properly calculated during the simulation of the patient's treatment. To this purposes several 3D geometry reconstruction techniques, generally based on the CT scanning data, are implemented and Monte Carlo codes are normally used. The TPSs are expected to show also the results (basically doses and fluences) in a proper format, such as isocurves (or isosurfaces) along t...
Design of the Trap Filter for the High Power Converters with Parallel Interleaved VSCs
DEFF Research Database (Denmark)
Gohil, Ghanshyamsinh Vijaysinh; Bede, Lorand; Teodorescu, Remus;
2014-01-01
. Therefore, large filter components are often required in order to meet the stringent grid code requirements imposed by the utility. As a result, the size, weight and cost of the overall system increase. The use of interleaved carriers of the parallel connected VSCs, along with the high order line filter, is...
A low cost digital filter design for seismic data acquisition based on FPGA and MCU
International Nuclear Information System (INIS)
A low cost and flexible digital filter solution for seismic data acquisition is put forward to improve performance of seismic data acquisition equipment. The purpose is to keep low frequency signal and realize high rate decimation at the same time. The digital filter system consists of four CIC filters which are realized in FPGA and two FIR filters which are realized in MCU. The CIC filters primary purpose is to attenuate out-of-band noise components from the modulator. The FIR filters compensates for SINC filters droop and creates a low-pass corner to block aliased components of the input signal. The digital filter has a good low-pass bandwidth performance, the frequency amplitude response drop 137 dB from 430 Hz to 500 Hz. A test system is build up, and the result shows that signal to noise ratio of this system is better than 110 dB, which meets the demand of seismic data acquisition system. (authors)
Design of Two-channel Half-band Bank of Digital Filters using Optimization Methods
Czech Academy of Sciences Publication Activity Database
Kubásek, R.; Smékal, Z.; Gescheidtová, E.; Bartušek, Karel
Los Alamitos : IEEE Computer Society, 2006, -:1-4. ISBN 0-7695-2552-0. [ICN 2006 - Networking /5./. Morne (MU), 23.04.2006-29.04.2006] Institutional research plan: CEZ:AV0Z20650511 Keywords : two-channel bank of digital filters * basic low -pass filter * transfer function Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering
The refinement of dose assessment of the THOR BNCT beam
International Nuclear Information System (INIS)
A refined dose assessment method has been used now in the THOR BNCT facility, which takes into account more delicate corrections, carefully handled calibration factors, and the spectrum- and kerma-weighted kt value. The refined method solved the previous problem of negative derived neutron dose in phantom at deeper positions. With the improved dose assessment, the calculated and measured gamma-ray dose rates match perfectly in a 15×15×15 cm3 PMMA phantom.
Zhang, Guiju; Cao, Bing; Zhang, Ke; Wang, Chinhua; Sun, Qian
2015-01-01
Developments in micro and nanofabrication technologies have led a variety of grating waveguide structures (GWS) being proposed and implemented in optics and laser application systems. A new design of multilayered nanostructure double-grating is described for reflection notch filter. Thin metal film and dielectric film are used and designed with one-dimensional composite gratings. The results calculated by rigorous coupled-wave analysis (RCWA) present that the thin metal film between substrate...
Emadi, A.; Wu, H; De Graaf, G.; Wolffenbuttel, R.F.
2011-01-01
In this paper the concept of a microspectrometer based on a Linear Variable Optical Filter (LVOF) for operation in the visible spectrum is presented and used in two different designs: the first is for the narrow spectral band between 610 nm and 680 nm, whereas the other is for the wider spectral band between 570 nm and 740 nm. Design considerations, fabrication and measurement results of the LVOF are presented. An iterative signal processing algorithm based on an initial calibration has been ...