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Sample records for fabric filter ff

  1. Comparison of the dosimetric parameters in linear accelerators with flattening filter-free (FFF) and flattening filter (FF)

    International Nuclear Information System (INIS)

    Souza, Anderson S.; Rostelato, Maria Elisa C.M.; Zeituni, Carlos A.; Moura, Eduardo S.; Rodrigues, Bruna T.; Souza, Daiane C.; Tiezzi, Rodrigo; Souza, Carla D.; Melo, Emerson R.; Camargo, Anderson R.; Batista, Talita Q.

    2015-01-01

    This paper discusses the main features associated with the dosimetric parameters between FFF and FF Linacs. A set of Varian TrueBeam Linac and Varian 23EX dosimetric measurements was acquired to perform the experimental measurements. The dose measurements were carried out in a water Blue phantom, with a waterproof ionization chambers: farmer ionization chamber (0.6 cm 3 ) and Exradin A1SL(0.053 cm 3 ) , for fields 5 x 5, 8 x 8, 10 x 10, 15 x 15, 30 x 30 cm 2 . The 6 MV FFF and FF was the energy used in this work. Percent Depth Dose (PDD) was the dosimetric parameters evaluated using a fixed Source Surface Distance of 100 cm. One depth were applied for the measurements, 10 cm (central axis) from the water surface. The 6 MV FFF showed less penetrating than the 6 MV FF. This is due to the removal flattening filter causes more lower energy photons on the central axis. The field sizes were equivalent for both FFF and FF. The main advantage in operate linear accelerators without flattening filter is due to the high doses rates delivered during the treatment. High doses rates could reduce the patient treatment time and may be beneficial for some treatment techniques such as IMRT and SRT. (author)

  2. Comparison of Flattening Filter (FF) and Flattening-Filter-Free (FFF) 6 MV photon beam characteristics for small field dosimetry using EGSnrc Monte Carlo code

    Science.gov (United States)

    Sangeetha, S.; Sureka, C. S.

    2017-06-01

    The present study is focused to compare the characteristics of Varian Clinac 600 C/D flattened and unflattened 6 MV photon beams for small field dosimetry using EGSnrc Monte Carlo Simulation since the small field dosimetry is considered to be the most crucial and provoking task in the field of radiation dosimetry. A 6 MV photon beam of a Varian Clinac 600 C/D medical linear accelerator operates with Flattening Filter (FF) and Flattening-Filter-Free (FFF) mode for small field dosimetry were performed using EGSnrc Monte Carlo user codes (BEAMnrc and DOSXYZnrc) in order to calculate the beam characteristics using Educated-trial and error method. These includes: Percentage depth dose, lateral beam profile, dose rate delivery, photon energy spectra, photon beam uniformity, out-of-field dose, surface dose, penumbral dose and output factor for small field dosimetry (0.5×0.5 cm2 to 4×4 cm2) and are compared with magna-field sizes (5×5 cm2 to 40×40 cm2) at various depths. The results obtained showed that the optimized beam energy and Full-width-half maximum value for small field dosimetry and magna-field dosimetry was found to be 5.7 MeV and 0.13 cm for both FF and FFF beams. The depth of dose maxima for small field size deviates minimally for both FF and FFF beams similar to magna-fields. The depths greater than dmax depicts a steeper dose fall off in the exponential region for FFF beams comparing FF beams where its deviations gets increased with the increase in field size. The shape of the lateral beam profiles of FF and FFF beams varies remains similar for the small field sizes less than 4×4 cm2 whereas it varies in the case of magna-fields. Dose rate delivery for FFF beams shows an eminent increase with a two-fold factor for both small field dosimetry and magna-field sizes. The surface dose measurements of FFF beams for small field size were found to be higher whereas it gets lower for magna-fields than FF beam. The amount of out-of-field dose reduction gets

  3. Comparison of k Q factors measured with a water calorimeter in flattening filter free (FFF) and conventional flattening filter (cFF) photon beams

    Science.gov (United States)

    de Prez, Leon; de Pooter, Jacco; Jansen, Bartel; Perik, Thijs; Wittkämper, Frits

    2018-02-01

    Recently flattening filter free (FFF) beams became available for application in modern radiotherapy. There are several advantages of FFF beams over conventional flattening filtered (cFF) beams, however differences in beam spectra at the point of interest in a phantom potentially affect the ion chamber response. Beams are also non-uniform over the length of a typical reference ion chamber and recombination is usually larger. Despite several studies describing FFF beam characteristics, only a limited number of studies investigated their effect on k Q factors. Some of those studies predicted significant discrepancies in k Q factors (0.4% up to 1.0%) if TPR20,10 based codes of practice (CoPs) were to be used. This study addresses the question to which extent k Q factors, based on a TPR20,10 CoP, can be applied in clinical reference dosimetry. It is the first study that compares k Q factors measured directly with an absorbed dose to water primary standard in FFF-cFF pairs of clinical photon beams. This was done with a transportable water calorimeter described elsewhere. The measurements corrected for recombination and beam radial non-uniformity were performed in FFF-cFF beam pairs at 6 MV and 10 MV of an Elekta Versa HD for a selection of three different Farmer-type ion chambers (eight serial numbers). The ratio of measured k Q factors of the FFF-cFF beam pairs were compared with the TPR20,10 CoPs of the NCS and IAEA and the %dd(10) x CoP of the AAPM. For the TPR20,10 based CoPs differences less than 0.23% were found in k Q factors between the corresponding FFF-cFF beams with standard uncertainties smaller than 0.35%, while for the %dd(10) x these differences were smaller than 0.46% and within the expanded uncertainty of the measurements. Based on the measurements made with the equipment described in this study the authors conclude that the k Q factors provided by the NCS-18 and IAEA TRS-398 codes of practice can be applied for flattening filter free beams without

  4. Model for predicting fabric filter and ESP costs

    International Nuclear Information System (INIS)

    Hoskins, W.; Terrill, J.K.

    1992-01-01

    United Engineers and Constructors (UE and C) has developed a personal computer (PC) based program (Model) for estimating capital and operating costs of fabric filters (FFs) and electrostatic precipitators (ESPs). The program contains proprietary sizing routines for both types of particulate control devices. For the FF, it determines the number of compartments, number of bags, physical dimensions and other important information. For the ESP, it determines specific collection area (SCA), number of cells, and number of TR sets. This paper reports that the program has the capability of handling a wide range of gas flows. It adjusts construction costs for the labor productivity factors in different locations. The capital costs are considered conceptual in nature with an absolute accuracy range of ±25%. The capital and operating costs are used along with economic factors to determine present worth costs. This allows site specific side-by-side comparisons of FFs and ESPs

  5. Ion exchange nonwoven fabric chemical filter. 2

    International Nuclear Information System (INIS)

    Sekiguchi, Hideaki

    2000-01-01

    This report outlined the characteristics of EPIX filter and its complex with activated carbon to eliminate organic compounds from solvent. Elimination performance of this filter was determined using an ion chromatographic analyzer. EPIX filter showed high performance to eliminate trace amount of ionic compounds. The rate of elimination was both 99% or more for NH 3 and SO 2 in an early phase of filtration. Release of dust as well as impurities was significantly reduced by the use of EPIX filter. Gases once adsorbed on the filter were not released even at an elevated temperature of atmosphere. Combined use of non-woven fabrics was possible. For EPIX filter, there are three kinds; strong acid cation exchange filter and strong/weak basic anion filters. The weak basic anion filter has been applied to the conventional apparatus in wafer makers because the filter was very effective for selective boron trapping. When polyethyleneterephthalate was used as the base polymer, radical groups produced on the polymer were co-polymerized with monomer substances. The lifetime of filter was estimated on a base of gas concentration and wind velocity to determine the time to replace with a new one. Furthermore, the loss of pressure became less than a half when EPIX filter was used. (M.N.)

  6. Design and fabrication of broadband rugate filter

    International Nuclear Information System (INIS)

    Zhang Jun-Chao; Fang Ming; Shao Yu-Chuan; Jin Yun-Xia; He Hong-Bo

    2012-01-01

    The design and the deposition of a rugate filter for broadband applications are discussed. The bandwidth is extended by increasing the rugate period continuously with depth. The width and the smoothness of the reflection band with the distribution of the periods are investigated. The improvement of the steepness of the stopband edges and the suppression of the side lobes in the transmission zone are realized by adding two apodized rugate structures with fixed periods at the external broadband rugate filter interfaces. The rapidly alternating deposition technology is used to fabricate a rugate filter sample. The measured transmission spectrum with a reflection bandwidth of approximately 505 nm is close to that of the designed broadband rugate filter except a transmittance peak in the stopband. Based on the analysis of the cross-sectional scanning electron microscopic image of the sample, it is found that the transmission peak is most likely to be caused by the instability of the deposition rate. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  7. Evaluation of filter fabrics for use in silt fences.

    Science.gov (United States)

    1980-01-01

    The study reported was initiated to develop tests simulating field conditions that could be used to develop information for the formulation of specifications for use in purchasing filter fabrics to be used to construct silt fences. Fifteen fabrics we...

  8. Design and fabrication of magnetic coolant filter

    Science.gov (United States)

    Prashanth, B. N.

    2017-07-01

    Now a day's use of coolants in industry has become dominant because of high production demands. Coolants not only help in speeding up the production but also provide many advantages in the metal working operation. As the consumption of coolants is very high a system is badly in need, so as to recirculate the used coolant. Also the amount of hazardous waste generated by industrial plants has become an increasingly costly problem for the manufactures and an additional stress on the environment. Since the purchase and disposal of the spent cutting fluids is becoming increasingly expensive, fluid recycling is a viable option for minimizing the cost. Separation of metallic chips from the coolants by using magnetic coolant separation has proven a good management and maintenance of the cutting fluid. By removing the metallic chips, the coolant life is greatly extended, increases the machining quality and reduces downtime. Above being the case, a magnetic coolant filter is developed which utilizes high energy permanent magnets to develop a dense magnetic field along a narrow flow path into which the contaminated coolant is directed. The ferromagnetic particles captured and aligned by the dense magnetic field, from the efficient filter medium. This enables the unit to remove ferromagnetic particles from the coolant. Magnetic coolant filters use the principle of magnetic separation to purify the used coolant. The developed magnetic coolant separation has the capability of purifying 40 litres per minute of coolant with the size of the contaminants ranging from 1 µm to 30 µm. The filter will be helpful in saving the production cost as the cost associated with the proposed design is well justified by the cost savings in production. The magnetic field produced by permanent magnets will be throughout the area underneath the reservoir. This produces magnetic field 30mm above the coolant reservoir. Very fine particles are arrested without slip. The magnetic material used will not

  9. Multichannel silicon WDM ring filters fabricated with DUV lithography

    Science.gov (United States)

    Lee, Jong-Moo; Park, Sahnggi; Kim, Gyungock

    2008-09-01

    We have fabricated 9-channel silicon wavelength-division-multiplexing (WDM) ring filters using 193 nm deep-ultraviolet (DUV) lithography and investigated the spectral properties of the ring filters by comparing the transmission spectra with and without an upper cladding. The average channel-spacing of the 9-channel WDM ring filter with a polymeric upper cladding is measured about 1.86 nm with the standard deviation of the channel-spacing about 0.34 nm. The channel crosstalk is about -30 dB, and the minimal drop loss is about 2 dB.

  10. Fabrication of a Cryogenic Bias Filter for Ultrasensitive Focal Plane

    Science.gov (United States)

    Chervenak, James; Wollack, Edward

    2012-01-01

    A fabrication process has been developed for cryogenic in-line filtering for the bias and readout of ultrasensitive cryogenic bolometers for millimeter and submillimeter wavelengths. The design is a microstripline filter that cuts out, or strongly attenuates, frequencies (10 50 GHz) that can be carried by wiring staged at cryogenic temperatures. The filter must have 100-percent transmission at DC and low frequencies where the bias and readout lines will carry signal. The fabrication requires the encapsulation of superconducting wiring in a dielectric-metal envelope with precise electrical characteristics. Sufficiently thick insulation layers with high-conductivity metal layers fully surrounding a patterned superconducting wire in arrayable formats have been demonstrated. A degenerately doped silicon wafer has been chosen to provide a metallic ground plane. A metallic seed layer is patterned to enable attachment to the ground plane. Thick silicon dioxide films are deposited at low temperatures to provide tunable dielectric isolation without degrading the metallic seed layer. Superconducting wiring is deposited and patterned using microstripline filtering techniques to cut out the relevant frequencies. A low Tc superconductor is used so that it will attenuate power strongly above the gap frequency. Thick dielectric is deposited on top of the circuit, and then vias are patterned through both dielectric layers. A thick conductive film is deposited conformally over the entire circuit, except for the contact pads for the signal and bias attachments to complete the encapsulating ground plane. Filters are high-aspect- ratio rectangles, allowing close packing in one direction, while enabling the chip to feed through the wall of a copper enclosure. The chip is secured in the copper wall using a soft metal seal to make good thermal and electrical contact to the outer shield.

  11. Non toxic additives for improved fabric filter performance

    Energy Technology Data Exchange (ETDEWEB)

    Bustard, C.J.; Baldrey, K.E.; Ebner, T.G. [ADA Technologies, Inc., Englewood, CO (United States)] [and others

    1995-11-01

    The overall objective of this three-phase Small Business innovative Research (SBIR) program funded by the Department of Energy pittsburgh Energy Technology Center (PETC) is to commercialize a technology based upon the use of non-toxic, novel flue gas conditioning agents to improve particulate air toxic control and overall fabric filter performance. The ultimate objective of the Phase II program currently in progress is to demonstrate that the candidate additives are successful at full-scale on flue gas from a coal-fired utility boiler. This paper covers bench-scale field tests conducted during the period February through May, 1995. The bench-scale additives testing was conducted on a flue gas slipstream taken upstream of the existing particulate control device at a utility power plant firing a Texas lignite coal. These tests were preceded by extensive testing with additives in the laboratory using a simulated flue gas stream and re-dispersed flyash from the same power plant. The bench-scale field testing was undertaken to demonstrate the performance with actual flue gas of the bet candidate additives previously identified in the laboratory. Results from the bench-scale tests will be used to establish operating parameters for a larger-scale demonstration on either a single baghouse compartment or a full baghouse at the same site.

  12. Comparative study of the parameters associated with quality control and absorbed dose in linear accelerators with (FF) and without (FFF) flattening filter

    International Nuclear Information System (INIS)

    Souza, Anderson Sorgatti de

    2017-01-01

    Teletherapy, radiation therapy with linear accelerators, for cancer treatment has being used for years with good clinical results.Since the 90's the removal of the flattening filter, item placed at the gantry of the machine, has shown better results for the treatment of some cancers thus being extensively studied. Treatments with Intensity Modulated Radiotherapy (IMRT) and Stereotaxic Radiotherapy (SRT) were more efficient without the flattening filter. Varian Oncology released the TrueBeam in 2012, a accelerator capable of operating with or without the flattening filter. The aim of this work is to access homogeneity of the percentage depth dose (PDP) and beam quality index (TPR20/10), two important parameters used in patient dose calculations. The data used for analysis were obtained with the Israelita Albert Einstein Hospital (HIAE), Real Portugues Hospital (RHP) and 3 more institutions located in the United States. The statistical data analysis allowed to observe the parameters behaviors. In general, they were very homogeneous, with errors smaller than 1% confirming the conformance of the TrueBeam accelerators. (author)

  13. Polymeric THz 2D Photonic Crystal Filters Fabricated by Fiber Drawing

    DEFF Research Database (Denmark)

    Stecher, Matthias; Jansen, Christian; Ahmadi-Boroujeni, Mehdi

    2012-01-01

    In this paper, we report on a new form of polymeric 2D photonic crystal filters for THz frequencies fabricated using a standard fiber drawing technique. The band stop filters were modeled and designed using the generalized multipole technique. The frequency and angle-dependent transmission...

  14. Rapid monitoring particulate radiocesium with nonwoven fabric cartridge filter and application to field monitoring

    International Nuclear Information System (INIS)

    Tsuji, Hideki; Yasutaka, Tetsuo; Kondo, Yoshihiko; Kawashima, Shoji

    2013-01-01

    A method for rapid monitoring particulate radiocesium using a nonwoven fabric cartridge filter was developed, which needs no further preprocessing before served to a detector. By a performance test, more than 98% of suspended solid (SS) was collected. This method showed the same radioactivity measurement accuracy as filtration by membrane filter and more rapid extraction capability of SS. (author)

  15. Fabrication of porous zirconia using filter paper template

    International Nuclear Information System (INIS)

    Deng Yuhua; Wei Pan

    2005-01-01

    In this work, porous zirconia ceramic was synthesized using filter papers as a template. Special attention is paid to whether the structural of the filter paper can be transferred to the zirconia structure. Microstructure of so synthesized porous zirconia was observed with SEM and the phase was determined by XRD. The surface area and the pore were investigated with an automatic volumetric sorption analyzer. It has been found that the morphology of the template transmit to the porous zirconia quite well. (orig.)

  16. Numerical and experimental study of pulse-jet cleaning in fabric filters

    DEFF Research Database (Denmark)

    O. Andersen, B.; Nielsen, N. F.; Walther, J. H.

    2016-01-01

    Pulse-jet cleaning and understanding of the complex physics are essential when designing fabric filters used for air pollution control. Today, low-pressure cleaning is of particular interest due to demand for reduced compressed air consumption. Pulse-jet cleaned fabric filters have been studied......-pressure fabric filters (2 bar) is studied using a full three-dimensional (3D) CFD model. Experimental results obtained in a pilot-scale test filter with 28 bags, in length of 10 m and in general full-scale dimensions of the cleaning system are used to verify the reliability of the present CFD model....... The validated CFD model reveals the strong compressible effects, a highly transient behaviour, the formation of compressible vortex rings and the shock cell phenomenon within the overexpanded supersonic jet. The cleaning nozzles and venturi design aid or oppose the pulse-pressure within the bags, and this plays...

  17. SERS substrates fabricated using ceramic filters for the detection of bacteria: Eliminating the citrate interference

    Science.gov (United States)

    Mosier-Boss, P. A.; Sorensen, K. C.; George, R. D.; Sims, P. C.; O'braztsova, A.

    2017-06-01

    It was found that spectra obtained for bacteria on SERS substrates fabricated by filtering citrate-generated Ag nanoparticles (NPs) onto rigid, ceramic filters exhibited peaks due to citrate as well as the bacteria. In many cases the citrate spectrum overwhelmed that of the bacteria. Given the simplicity of the method to prepare these substrates, means of eliminating this citrate interference were explored. It was found that allowing a mixture of bacteria suspension and citrate-generated Ag NPs to incubate prior to filtering onto the ceramic filter eliminated this interference.

  18. DESIGN AND FABRICATION OF MULTI STAGE CUTTING OIL FILTER SYSTEM

    OpenAIRE

    ABHIJIT S. GETME , ADITENDRA JAISWAL

    2018-01-01

    Multistage oil filtration system is a system used to filter out all the metallic, non metallic particles from the cutting fluid, which is used during the machining processes. Basic procedures we are using in it are: centrifugal process, magnetic filtration, paper filtration.

  19. Report of an investigation into deterioration of the Plutonium Fuel Form Fabrication Facility (PuFF) at the DOE Savannah River Site

    International Nuclear Information System (INIS)

    1991-10-01

    This investigations of the Savannah River Site's Plutonium Fuel Form fabrication facility located in Building 235-F was initiated in April 1991. The purpose of the investigation was to determine whether, as has been alleged, operation of the facility's argon inert gas system was terminated with the knowledge that continued inoperability of the argon system would cause accelerated corrosion damage to the equipment in the plutonium 238 processing cells. The investigation quickly established that the decision to discontinue operation of the argon system, by not repairing it, was merely one of the measures, and not the most important one, which led to the current deteriorated state of the facility. As a result, the scope of the investigation was broadened to more identify and assess those factors which contributed to the facility's current condition. This document discusses the backgrounds, results, and recommendations of this investigation

  20. Report of an investigation into deterioration of the Plutonium Fuel Form Fabrication Facility (PuFF) at the DOE Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This investigations of the Savannah River Site's Plutonium Fuel Form fabrication facility located in Building 235-F was initiated in April 1991. The purpose of the investigation was to determine whether, as has been alleged, operation of the facility's argon inert gas system was terminated with the knowledge that continued inoperability of the argon system would cause accelerated corrosion damage to the equipment in the plutonium 238 processing cells. The investigation quickly established that the decision to discontinue operation of the argon system, by not repairing it, was merely one of the measures, and not the most important one, which led to the current deteriorated state of the facility. As a result, the scope of the investigation was broadened to more identify and assess those factors which contributed to the facility's current condition. This document discusses the backgrounds, results, and recommendations of this investigation.

  1. SERS substrates fabricated using ceramic filters for the detection of bacteria

    Science.gov (United States)

    Mosier-Boss, P. A.; Sorensen, K. C.; George, R. D.; Obraztsova, A.

    2016-01-01

    SERS substrates were fabricated by filtering either Ag or Au colloidal particles onto rigid, ceramic filters - onto which suspensions of bacteria were then filtered. SERS spectra of the bacteria were obtained using a Raman spectrometer that has an 'orbital raster scan' capability. It was shown that bacteria samples prepared in this manner were uniformly distributed onto the surface of the SERS substrate. The effect of common buffer systems on the SERS spectra was investigated and the utility of using the SERS technique for speciation of bacteria was explored.

  2. Design and fabrication of a 100 GHz channel-drop filter

    Energy Technology Data Exchange (ETDEWEB)

    Smirnova, Evgenya I [Los Alamos National Laboratory; Earley, Lawrence M [Los Alamos National Laboratory; Heath, Cynthia E [Los Alamos National Laboratory; Shchegolkov, Dmitry Y [Los Alamos National Laboratory

    2008-01-01

    We have designed and are fabricating a novel passive mm-wave spectrometer based on a Photonic Band Gap (PBG) channel-drop filter (CDF). There is a need for a compact wide-band versatile and configurable mm-wave spectrometer for applications in mm-wave communications, radio astronomy, and radar receivers for remote sensing and nonproliferation.

  3. FF / Kaisa Karu

    Index Scriptorium Estoniae

    Karu, Kaisa

    2008-01-01

    Haapsalu õudusfilmide festivalil HÕFF linastuvaid filme - "Ajaroimad" ("Los Cronocrimenes"; režii Nacho Vigalondo), "Mudapoiss" ("El nino de barro"; Jorge Algora), "Orbudekodu" (El orfanato"; Juan Antonio Bayona)

  4. Design, Fabrication and Installation of the Charcoal Filter Housing in RIPF

    International Nuclear Information System (INIS)

    Kim, Min Jin; Lim, I. C.; Bang, H. S.

    2008-05-01

    In the Hot Cell Bank 3 of the Radioisotope Production Facility, production and dispense of I-131 solution and capsule that are used for the diagnosis and treatment of thyroid cancer are made. The original charcoal filter housings installed in 1994 and were utilized until the leakage of a very small amount of radio-iodine was found due to the erroneous installation of the charcoal filter in the filter housing. Thus the production of I-131 was discontinued until the repair and performance testing of the filter housing and the inspection by the regulatory body were finished. Although the production of I-131 was resumed, there was a desire for installing the brand-new charcoal filter housing which has an intrinsically safe design and no possibility of leakage. This report describes the design, fabrication and installation of brand-new charcoal filter housing. And also were described the dismantlement of the old housings, the assessment of the structural integrity of the shielding concrete wall and the installation of the shielding doors

  5. Fabrication of dense wavelength division multiplexing filters with large useful area

    Science.gov (United States)

    Lee, Cheng-Chung; Chen, Sheng-Hui; Hsu, Jin-Cherng; Kuo, Chien-Cheng

    2006-08-01

    Dense Wavelength Division Multiplexers (DWDM), a kind of narrow band-pass filter, are extremely sensitive to the optical thickness error in each composite layer. Therefore to have a large useful coating area is extreme difficult because of the uniformity problem. To enlarge the useful coating area it is necessary to improve their design and their fabrication. In this study, we discuss how the tooling factors at different positions and for different materials are related to the optical performance of the design. 100GHz DWDM filters were fabricated by E-gun evaporation with ion-assisted deposition (IAD). To improve the coating uniformity, an analysis technique called shaping tooling factor (STF) was used to analyze the deviation of the optical thickness in different materials so as to enlarge the useful coating area. Also a technique of etching the deposited layers with oxygen ions was introduced. When the above techniques were applied in the fabrication of 100 GHz DWDM filters, the uniformity was better than +/-0.002% over an area of 72 mm in diameter and better than +/-0.0006% over 20mm in diameter.

  6. Design and fabrication of bandwidth tunable HTS transmit filter using {pi}-shaped waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Sekiya, N., E-mail: nsekiya@yamanashi.ac.j [Department of Electrical Engineering, Yamanashi University, Nakagawa-Sekiya Laboratory, 4-3-11 Takeda, Kofu 400-8511 (Japan); Harada, H.; Nakagawa, Y. [Department of Electrical Engineering, Yamanashi University, Nakagawa-Sekiya Laboratory, 4-3-11 Takeda, Kofu 400-8511 (Japan); Ono, S.; Ohshima, S. [Yamagata University, 4-3-16 Johnan, Yonezawa 992-8510 (Japan)

    2010-11-01

    We have developed a method for tuning the bandwidth of a high-temperature superconducting (HTS) microstrip filter. Several {pi}-shaped waveguides are placed between the resonators, and the bandwidth is tuned in discrete steps by changing the switch states of the waveguides, which changes the coupling coefficient between the resonators. The filter contains 3-pole half-wavelength straight-line resonators and two {pi}-shaped waveguides for bandwidth tuning. It also has several electrical pads distributed around the feed lines for trimming after tuning. The filter was fabricated by depositing YBa{sub 2}Cu{sub 3}O{sub 7} thin film on an MgO substrate and has a measured center frequency of 5.17 GHz and bandwidth of 220 MHz. Use of the {pi}-shaped waveguides to adjust the coupling coefficients and the electrical pads to adjust the external quality factors resulted in 80-MHz bandwidth tuning without increased insertion loss.

  7. Guided-mode resonant filters and reflectors: Principles, design, and fabrication

    Science.gov (United States)

    Niraula, Manoj

    In this dissertation, we overview the operational principles of these resonant periodic structures, discuss the methods of their design and fabrication, and propose and demonstrate novel functionalities for spatial and spectral filtering, and unpolarized wideband reflection. Fashioned with materially sparse gratings, these optical devices are easy to fabricate and integration friendly compared to their traditional multi-layer counterparts making their research and development critical for practical applications. We study, theoretically, modal properties and parametric dependence of resonant periodic bandpass filters operating in the mid- and near-infrared spectral domains. We investigate three different device architectures consisting of single, double, and triple layers based on all-transparent dielectric and semiconductor thin films. We present three modal coupling configurations forming complex mixtures of two or three distinct leaky modes coupling at different evanescent diffraction orders. Our modal analysis demonstrates key attributes of subwavelength periodic thin-film structures in multiple-modal blending to achieve desired transmission spectra. We provide the first experimental demonstration of high-efficiency and narrow-linewidth resonant bandpass filter applying a single patterned silicon layer on a quartz substrate. Its performance corresponds to bandpass filters requiring 15 traditional Si/SiO2 thin-film layers. The feasibility of sparse narrowband, high-efficiency bandpass filters with extremely wide, flat, and low sidebands is thereby demonstrated. The proposed technology is integration-friendly and opens doors for further development in various disciplines and spectral regions where thin-film solutions are traditionally applied. We demonstrate concurrent spatial and spectral filtering as a new outstanding attribute of resonant periodic devices. This functionality is enabled by a unique, near-complete, reflection state that is discrete in both

  8. Effects of fixture rotation on coating uniformity for high-performance optical filter fabrication

    Science.gov (United States)

    Rubin, Binyamin; George, Jason; Singhal, Riju

    2018-04-01

    Coating uniformity is critical in fabricating high-performance optical filters by various vacuum deposition methods. Simple and planetary rotation systems with shadow masks are used to achieve the required uniformity [J. B. Oliver and D. Talbot, Appl. Optics 45, 13, 3097 (2006); O. Lyngnes, K. Kraus, A. Ode and T. Erguder, in `Method for Designing Coating Thickness Uniformity Shadow Masks for Deposition Systems with a Planetary Fixture', 2014 Technical Conference Proceedings, Optical Coatings, August 13, 2014, DOI: 10.14332/svc14.proc.1817.]. In this work, we discuss the effect of rotation pattern and speed on thickness uniformity in an ion beam sputter deposition system. Numerical modeling is used to determine statistical distribution of random thickness errors in coating layers. The relationship between thickness tolerance and production yield are simulated theoretically and demonstrated experimentally. Production yields for different optical filters produced in an ion beam deposition system with planetary rotation are presented. Single-wavelength and broadband optical monitoring systems were used for endpoint monitoring during filter deposition. Limitations of thickness tolerances that can be achieved in systems with planetary rotation are shown. Paths for improving production yield in an ion beam deposition system are described.

  9. Comparative study of the parameters associated with quality control and absorbed dose in linear accelerators with (FF) and without (FFF) flattening filter; Estudo comparativo dos parametros associados a dose absorvida e controle de qualidade em aceleradores lineares com filtro aplainador (FF) e sem filtro aplainador (FFF)

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Anderson Sorgatti de

    2017-11-01

    Teletherapy, radiation therapy with linear accelerators, for cancer treatment has being used for years with good clinical results.Since the 90's the removal of the flattening filter, item placed at the gantry of the machine, has shown better results for the treatment of some cancers thus being extensively studied. Treatments with Intensity Modulated Radiotherapy (IMRT) and Stereotaxic Radiotherapy (SRT) were more efficient without the flattening filter. Varian Oncology released the TrueBeam in 2012, a accelerator capable of operating with or without the flattening filter. The aim of this work is to access homogeneity of the percentage depth dose (PDP) and beam quality index (TPR20/10), two important parameters used in patient dose calculations. The data used for analysis were obtained with the Israelita Albert Einstein Hospital (HIAE), Real Portugues Hospital (RHP) and 3 more institutions located in the United States. The statistical data analysis allowed to observe the parameters behaviors. In general, they were very homogeneous, with errors smaller than 1% confirming the conformance of the TrueBeam accelerators. (author)

  10. Preliminary enviromagnetic comparison of the moss, lichen, and filter fabric bags to air pollution monitoring

    Directory of Open Access Journals (Sweden)

    Hanna Salo

    2014-08-01

    Full Text Available Air quality and anthropogenic air pollutants are usually investigated by passive biomonitoring which utilizes native species. Active biomonitoring, instead, refers to the use of transplants or bags in areas lacking native species. In Finland, the standardized moss bag technique SFS 5794 is commonly applied in active monitoring but there is still need for simpler and labor-saving sample material even on international scale. This article focuses on a preliminary comparison of the usability and collection efficiency of bags made of moss Sphagnum papillosum, lichen Hypogymnia physodes, and filter fabric (Filtrete™ in active biomonitoring of air pollutants around an industrial site in Harjavalta, SW Finland. The samples are analyzed with magnetic (i.e. magnetic susceptibility, isothermal remanent magnetization, hysteresis loop and hysteresis parameters methods highly suitable as a first-step tool for pollution studies. The results show that the highest magnetic susceptibility of each sample material is measured close to the industrial site. Furthermore, moss bags accumulate more magnetic material than lichen bags which, on the contrary, perform better at further distances. Filter fabric bags are tested only at 1 km sites indicating a good accumulation capability near the source. Pseudo-single-domain (PSD magnetite is identified as the main magnetic mineral in all sample materials and good correlations are found between different bag types. To conclude, all three materials effectively accumulate air pollutants and are suitable for air quality studies. The results of this article provide a base for later studies which are needed in order to fully determine a new, efficient, and easy sample material for active monitoring.

  11. Fabrication of antibacterial water filter by coating silver nanoparticles on flexible polyurethane foams

    International Nuclear Information System (INIS)

    Nguyen Thi Phuong Phong; Ngo Vo Ke Thanh; Phan Hue Phuong

    2009-01-01

    In this paper, we fabricated silver-coated polyurethane foams and used it as a bacterial filter for contaminated drinking water. Flexible PU foams were soaked in silver colloidal solutions for 10 h, then washed and air-dried at room temperature. The prepared silver colloidal solutions and silver-coated PU materials were characterized by several techniques including TEM, FESEM/EDS, UV-VIS, ICP-AAS, and Raman spectroscopy. The TEM images showed that the size of silver nanoparticles in colloidal solutions varies from 6 to 12nm. The Raman, FE-SEM/EDS and ICP-AAS data illustrated that silver nanoparticles were stable on the PU foam and were not washed away by water. Furthermore, the microbiological tests (tube tests and flow test) were carried out on silver-coated PU materials with the Coliforms, E. coli, and B. subtilis. The obtained results showed that the bacteria was killed completely with antibacterial efficiency of 100% being observed. Our research suggests that silver-coated polyurethane foams can be used as excellent antibacterial water filters and would have several applications in other sectors.

  12. Ultra-compact broadband higher order-mode pass filter fabricated in a silicon waveguide for multimode photonics

    DEFF Research Database (Denmark)

    Guan, Xiaowei; Ding, Yunhong; Frandsen, Lars Hagedorn

    2015-01-01

    An ultra-compact and broadband higher order-mode pass filter in a 1D photonic crystal silicon waveguide is proposed and experimentally demonstrated. The photonic crystal is designed for the lower order mode to work in the photonic band gap, while the higher order mode is located in the air band....... Consequently, light on the lower order mode is prohibited to pass through the filter, while light on a higher order mode can be converted to a Bloch mode in the photonic crystal and pass through the filter with low insertion loss. As an example, we fabricate a similar to 15-mu m-long first-order-mode pass...

  13. Fabricating high-resolution offset color-filter black matrix by integrating heterostructured substrate with inkjet printing

    International Nuclear Information System (INIS)

    Lu, Guo-Shin; You, Po-Chin; Lin, Kai-Lun; Hong, Chien-Chong; Liou, Tong-Miin

    2014-01-01

    This paper presents a self-aligning ink by integrating an inkjet printing technique and heterostructures to fabricate a black matrix with a micrometer-scale tunable thickness. The black matrix is a grid-like structure used in color filters. Traditionally, a black matrix has been fabricated using photolithography techniques, the disadvantages of which are high material consumption, less fabrication flexibility, complex processing procedures, and high chemical pollution. Inkjet printing technology has garnered attention because of its low material costs, high fabrication flexibility, and reduced processing procedures and pollution. In this study, a fabricating process combining an inkjet printing technique with heterostructures to form stripe-arranged and delta-arranged thickness-tunable black matrices has been demonstrated. The deformation and self-aligning process of ink droplet impingement onto gutters are driven by designed heterogeneous surface properties. The minimum track width attained is 10 µm, which is competitive for color filter resolutions for thin-film transistor liquid crystal displays. The developed technology surmounts the bottlenecks of inkjet printing resolution, and saves more than 75% black material than modern photolithography. (paper)

  14. FF kasvatab meeskonda / Tiina Sarv

    Index Scriptorium Estoniae

    Sarv, Tiina, 1949-

    2006-01-01

    9. mail sõlmisid Tartu Ülikooli Viljandi Kultuuriakadeemia ja Tallinna Pimedate Ööde Filmifestival Viljandis koostöölepingu, mille alusel hakkavad akadeemia tudengid tegema PÖFF-il õppepraktikat

  15. FF kasvatab meeskonda / Tiina Sarv

    Index Scriptorium Estoniae

    Sarv, Tiina, 1949-

    2006-01-01

    9. mail sõlmisid Viljandi Kultuuriakadeemia ja Tallinna Pimedate Ööde Filmifestival Viljandis koostöölepingu, mille põhjal hakkavad akadeemia kultuurikorralduse ja teatrikunsti visuaaltehnoloogia tudengid tegema PÖFF-il õppepraktikat

  16. Fabrication of TiO2/EP super-hydrophobic thin film on filter paper surface.

    Science.gov (United States)

    Gao, Zhengxin; Zhai, Xianglin; Liu, Feng; Zhang, Ming; Zang, Deli; Wang, Chengyu

    2015-09-05

    A composite filter paper with super-hydrophobicity was obtained by adhering micro/nano structure of amorphous titanium dioxide on the filter paper surface with modifying low surface energy material. By virtue of the coupling agent, which plays an important part in bonding amorphous titanium dioxide and epoxy resin, the structure of super-hydrophobic thin film on the filter paper surface is extremely stable. The microstructure of super-hydrophobic filter paper was characterized by scanning electron microscopy (SEM), the images showed that the as-prepared filter paper was covered with uniform amorphous titanium dioxide particles, generating a roughness structure on the filter paper surface. The super-hydrophobic performance of the filter paper was characterized by water contact angle measurements. The observations showed that the wettability of filter paper samples transformed from super-hydrophilicity to super-hydrophobicity with the water contact angle of 153 ± 1°. Some experiments were also designed to test the effect of water-oil separation and UV-resistant by the super-hydrophobic filter paper. The prepared super-hydrophobic filter paper worked efficiently and simply in water-oil separation as well as enduringly in anti-UV property after the experiments. This method offers an opportunity to the practical applications of the super-hydrophobic filter paper. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Fabrication of Compact Microstrip Line-Based Balun-Bandpass Filter with High Common-Mode Suppression

    Directory of Open Access Journals (Sweden)

    Chia-Mao Chen

    2014-01-01

    Full Text Available A new type of balun-bandpass filter was proposed based on the traditional coupled-line theory and folded open-loop ring resonators (OLRRs configuration. For that, a new device with both filter-type and balun-type characteristics was investigated and fabricated. Both magnetic and electric coupling structures were implemented to provide high performance balun-bandpass responses. The fabricated balun-bandpass filters had a wide bandwidth more than 200 MHz and a low insertion loss less than 2.51 dB at a center frequency of 2.6 GHz. The differences between the two outputs were below 0.4 dB in magnitude and within 180 ± 7° in phase. Also, the balun-bandpass filter presented an excellent common-mode rejection ratio over 25 dB in the passband. An advanced design methodology had been adopted based on EM simulation for making these designed parameters of OLRRs, microstrip lines, and open stubs. The measured frequency responses agreed well with simulated ones.

  18. Analysis of the FF Aqr spectra

    Science.gov (United States)

    Shimanskaya, N. N.; Bikmaev, I. F.; Shimansky, V. V.

    2011-07-01

    We determine the atmospheric parameters of the secondary in the close binary system FF Aqr and analyze its chemical composition. A series of high-resolution spectra are taken at different orbital phases using the coude echelle spectrometer of the 1.5-m Russian-Turkish Telescope (RTT150). We show that the absorption line intensity of heavy elements varies with phase due to the spotty nature of the cool component. We determine the abundances of heavy elements in the star's atmosphere by modelling the synthetic spectra and performing a differential analysis of the chemical composition of FF Aqr relative to the solar composition. Our analysis of the averaged spectrum of FF Aqr yielded 539 abundance estimates for 21 chemical elements. We found the metallicity of the star ([ Fe/H] = -0.11 ± 0.08) to be close solar, in agreement with the hypothesis that FF Aqr should belong to the Galactic disk. The inferred chemical composition of the objects exhibits no anomalous abundances of the α-, r-, and s-process elements like those earlier found in other systems (IN Com, LW Hya, V471 Tau). The lack of such anomalies in FF Aqr must be due to the fact that the elements heavier than 16 O cannot be synthesized in the core of the primary during the last stages of its evolution.

  19. Effect of Coil Current on the Properties of Hydrogenated DLC Coatings Fabricated by Filtered Cathodic Vacuum Arc Technique

    Science.gov (United States)

    Liao, Bin; Ouyang, Xiaoping; Zhang, Xu; Wu, Xianying; Bian, Baoan; Ying, Minju; Jianwu, Liu

    2018-01-01

    We successfully prepared hydrogenated DLC (a-C:H) with a thickness higher than 25 μm on stainless steel using a filtered cathode vacuum arc (FCVA) technique. The structural and mechanical properties of DLC were systematically analyzed using different methods such as x-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, Vickers hardness, nanohardness, and friction and wear tests. The effect of coil current on the arc voltage, ion current, and mechanical properties of resultant films was systematically investigated. The novelty of this study is the fabrication of DLC with Vickers hardness higher than 1500 HV, in the meanwhile with the thickness higher than 30 μm through varying the coil current with FCVA technique. The results indicated that the ion current, deposition rate, friction coefficient, and Vickers hardness of DLC were significantly affected by the magnetic field inside the filtered duct.

  20. Design and fabrication of multi-dielectric thin film laser filters and mirrors

    International Nuclear Information System (INIS)

    Alsous, M. B.

    2005-01-01

    Multi-dielectric-film optical filters have designed as mirrors for frequency-doubled-Nd-YAG pumped Raman lasers at different wavelengths (435, 369.9, 319.8, 953.6, 683 nm), and for use in CVL pumped dye lasers: as beam-splitters, antireflection filters, and narrow-band filters. In this work, a theoretical design of these mirrors and filters is given. The treatment and optimization of these designs is detailed in order to overcome the difficulties and reach the final and suitable designs for our needs. In addition, we will describe the evaporation method and the best conditions to do it. These filters should be easy to make and able to resist the laser powers of the pulsed Nd-YAG laser (200mJ/pulse) and the output power of the CVL. Thus, we have adopted designs with the least number of layers and used materials and oxides, which could resist to high laser powers. These filters were tested with laser shots and the convenient designs that were able to support the laser power have been adopted. (Author)

  1. Novel fabrication method of the peritoneal dialysis filter using silk fibroin with urease fixation system.

    Science.gov (United States)

    Moon, Bo Mi; Choi, Myung-Jin; Sultan, Md Tipu; Yang, Jae Won; Ju, Hyung Woo; Lee, Jung Min; Park, Hyun Jung; Park, Ye Ri; Kim, Soo Hyeon; Kim, Dong Wook; Lee, Min Chae; Jeong, Ju Yeon; Lee, Ok Joo; Sung, Gun Yong; Park, Chan Hum

    2017-10-01

    During the last decade, there has been a great advance in the kidney dialysis system by wearable artificial kidney (WAK) system for end-stage renal disease patients. Uremic solute removal and water regeneration system are the most prerequisite for WAK to work properly. In this study, we designed a filtering membrane system by using immobilized urease silk fibroin filter and evaluated its comparative effectiveness with a PVDF filtering system in peritoneal dialysate regeneration system by urea removal efficacy. We evaluated this membrane's characteristic and performances by conducting SEM-EDX analyze, water-binding abilities and porosity test, removal abilities of urea, cytotoxicity assay and enzyme activity assay. Under the condition for optimization of urease, the percentage removal of urea was about 40% and 60% in 50 mg/dL urea solution by urease immobilized PVDF and silk fibroin scaffolds, respectively. The batch experimental result showed that immobilized filter removed more than 50% of urea in 50 mg/dL urea solution. In addition silk fibroin with urease filter removed 90 percent of urea in the peritoneal dialysate after 24 h filtration. We suggest that silk fibroin with urease fixation filter can be used more effectively for peritoneal dialysate regeneration system, which have hydrophilic property and prolonged enzyme activity. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2136-2144, 2017. © 2016 Wiley Periodicals, Inc.

  2. Preparation and characterization of a novel sodium alginate incorporated self-assembled Fmoc-FF composite hydrogel

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Xiao [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620 (China); Branford-White, Christopher [Institute for Health Research and Policy, London Metropolitan University, London N78 DB (United Kingdom); Tao, Lei [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Li, Shubai [Changzhou Institute of Engineering Technology, Changzhou 213164 (China); Quan, Jing [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Nie, Huali, E-mail: niehuali@dhu.edu.cn [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620 (China); Zhu, Limin, E-mail: lzhu@dhu.edu.cn [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China)

    2016-01-01

    Dipeptides and their derivatives have attracted tremendous attention owning to their excellent abilities of self-assemble assembling into various structures which have great potentials for applications in biology and/or nanotechnology. In the present study, we dedicate to fabricate a rigid and structure controllable Fmoc-FF/SA composite hydrogel. We found that the modified dipeptide, fluorenyl-9-methoxycarbonyl (Fmoc)-diphenylalanine (Phe-Phe) can self-assemble into rigid hydrogels with structures of nanowires, layered thin films or honeycombs as the change of sodium alginate (SA) concentration. Meanwhile, CD-spectroscopy demonstrated that SA appeared to control the process, but it did not change the arrangement of the Fmoc-FF peptide. Our results demonstrated that the formed hydrogel showed physical and chemical stability as well as possessing good biocompatibility. Rheological measurements showed that the addition of SA could improve the stability of the hydrogel. Cell viability assay revealed that the Fmoc-FF and Fmoc-FF/SA hydrogels are both beneficial for cell proliferation in-vitro. Our results indicated that the fabricated Fmoc-FF/SA composite hydrogels could be used in tissue engineering and drug delivery in the future. - Highlights: • A facile, time-saving approach to assemble Fomc-FF composite hydrogels was designed. • Hydrogel structures including nanowires, layered films and honeycombs can be controlled. • The role of SA in the Fmoc-FF/SA composite hydrogel was further clarified.

  3. New approaches for the design and the fabrication of pixelated filters

    Science.gov (United States)

    Lumeau, J.; Lemarquis, F.; Begou, T.; Mathieu, K.; Savin De Larclause, I.; Berthon, J.

    2017-09-01

    Multispectral or hyperspectral images allow acquiring new information that could not be acquired using colored images and, for example, identifying chemical species on an observed scene using specific highly selective thin film filters. Those images are commonly used in numerous fields, e.g. in agriculture or homeland security and are of prime interest for imaging systems for onboard scientific applications (e.g. for planetology).

  4. Using a micro-molding process to fabricate polymeric wavelength filters

    Science.gov (United States)

    Chuang, Wei-Ching; Lee, An-Chen; Ho, Chi-Ting

    2008-08-01

    A procedure for fabricating a high aspect ratio periodic structure on a UV polymer at submicron order using holographic interferometry and molding processes is described. First, holographic interferometry using a He-Cd (325 nm) laser was used to create the master of the periodic line structure on an i-line sub-micron positive photoresist film. A 20 nm nickel thin film was then sputtered on the photoresist. The final line pattern on a UV polymer was obtained from casting against the master mold. Finally, a SU8 polymer was spun on the polymer grating to form a planar waveguide or a channel waveguide. The measurement results show that the waveguide length could be reduced for the waveguide having gratings with a high aspect ratio.

  5. Long-Term Carbon Injection Field Test for 90% Mercury Removal for a PRB Unit a Spray Dryer and Fabric Filter

    Energy Technology Data Exchange (ETDEWEB)

    Sjostrom, Sharon; Amrhein, Jerry

    2009-04-30

    The power industry in the U.S. is faced with meeting regulations to reduce the emissions of mercury compounds from coal-fired plants. Injecting a sorbent such as powdered activated carbon (PAC) into the flue gas represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. The purpose of this test program was to evaluate the long-term mercury removal capability, long-term mercury emissions variability, and operating and maintenance (O&M) costs associated with sorbent injection on a configuration being considered for many new plants. Testing was conducted by ADA Environmental Solutions (ADA) at Rocky Mountain Power’s (RMP) Hardin Station through funding provided by DOE/NETL, RMP, and other industry partners. The Hardin Station is a new plant rated at 121 MW gross that was first brought online in April of 2006. Hardin fires a Powder River Basin (PRB) coal and is configured with selective catalytic reduction (SCR) for NOx control, a spray dryer absorber (SDA) for SO2 control, and a fabric filter (FF) for particulate control. Based upon previous testing at PRB sites with SCRs, very little additional mercury oxidation from the SCR was expected at Hardin. In addition, based upon results from DOE/NETL Phase II Round I testing at Holcomb Station and results from similarly configured sites, low native mercury removal was expected across the SDA and FF. The main goal of this project was met—sorbent injection was used to economically and effectively achieve 90% mercury control as measured from the air heater (AH) outlet to the stack for a period of ten months. This goal was achieved with DARCO® Hg-LH, Calgon FLUEPAC®-MC PLUS and ADA Power PAC PREMIUM brominated activated carbons at nominal loadings of 1.5–2.5 lb/MMacf. An economic analysis determined the twenty-year levelized cost to be 0.87 mills/kW-hr, or $15,000/lb Hg removed. No detrimental effects on other equipment or plant operations were observed. The

  6. Fabrication of Activated Rice Husk Charcoal by Slip Casting as a Hybrid Material for Water Filter Aid

    International Nuclear Information System (INIS)

    Tuaprakone, T; Wongphaet, N; Wasanapiarnpong, T

    2011-01-01

    Activated charcoal has been widely used as an odor absorbent in household and water purification industry. Filtration equipment for drinking water generally consists of four parts, which are microporous membrane (porous alumina ceramic or diatomite, or porous polymer), odor absorbent (activated carbon), hard water treatment (ion exchange resin), and UV irradiation. Ceramic filter aid is usually prepared by slip casting of alumina or diatomite. The membrane offers high flux, high porosity and maximum pore size does not exceed 0.3 μm. This study investigated the fabrication of hybrid activated charcoal tube for water filtration and odor absorption by slip casting. The suitable rice husk charcoal and water ratio was 48 to 52 wt% by weight with 1.5wt% (by dry basis) of CMC binder. The green rice husk charcoal bodies were dried and fired between 700-900 deg. C in reduction atmosphere. The resulting prepared slip in high speed porcelain pot for 60 min and sintered at 700 deg. C for 1 h showed the highest specific surface area as 174.95 m 2 /g. The characterizations of microstructure and pore size distribution as a function of particle size were investigated.

  7. Fabrication of Activated Rice Husk Charcoal by Slip Casting as a Hybrid Material for Water Filter Aid

    Science.gov (United States)

    Tuaprakone, T.; Wongphaet, N.; Wasanapiarnpong, T.

    2011-04-01

    Activated charcoal has been widely used as an odor absorbent in household and water purification industry. Filtration equipment for drinking water generally consists of four parts, which are microporous membrane (porous alumina ceramic or diatomite, or porous polymer), odor absorbent (activated carbon), hard water treatment (ion exchange resin), and UV irradiation. Ceramic filter aid is usually prepared by slip casting of alumina or diatomite. The membrane offers high flux, high porosity and maximum pore size does not exceed 0.3 μm. This study investigated the fabrication of hybrid activated charcoal tube for water filtration and odor absorption by slip casting. The suitable rice husk charcoal and water ratio was 48 to 52 wt% by weight with 1.5wt% (by dry basis) of CMC binder. The green rice husk charcoal bodies were dried and fired between 700-900 °C in reduction atmosphere. The resulting prepared slip in high speed porcelain pot for 60 min and sintered at 700 °C for 1 h showed the highest specific surface area as 174.95 m2/g. The characterizations of microstructure and pore size distribution as a function of particle size were investigated.

  8. Fabrication of Activated Rice Husk Charcoal by Slip Casting as a Hybrid Material for Water Filter Aid

    Energy Technology Data Exchange (ETDEWEB)

    Tuaprakone, T; Wongphaet, N; Wasanapiarnpong, T, E-mail: tonggogo@hotmail.com [Research Unit of Advanced Ceramic, Department of Materials Science, Faculty of Science, Chulalongkorn University, Bangkok (Thailand)

    2011-04-15

    Activated charcoal has been widely used as an odor absorbent in household and water purification industry. Filtration equipment for drinking water generally consists of four parts, which are microporous membrane (porous alumina ceramic or diatomite, or porous polymer), odor absorbent (activated carbon), hard water treatment (ion exchange resin), and UV irradiation. Ceramic filter aid is usually prepared by slip casting of alumina or diatomite. The membrane offers high flux, high porosity and maximum pore size does not exceed 0.3 {mu}m. This study investigated the fabrication of hybrid activated charcoal tube for water filtration and odor absorption by slip casting. The suitable rice husk charcoal and water ratio was 48 to 52 wt% by weight with 1.5wt% (by dry basis) of CMC binder. The green rice husk charcoal bodies were dried and fired between 700-900 deg. C in reduction atmosphere. The resulting prepared slip in high speed porcelain pot for 60 min and sintered at 700 deg. C for 1 h showed the highest specific surface area as 174.95 m{sup 2}/g. The characterizations of microstructure and pore size distribution as a function of particle size were investigated.

  9. The electrocatalytic oxidation of carbohydrates at a nickel/carbon paper electrode fabricated by the filtered cathodic vacuum arc technique

    International Nuclear Information System (INIS)

    Fu, Yingyi; Wang, Tong; Su, Wen; Yu, Yanan; Hu, Jingbo

    2015-01-01

    The direct electrochemical behaviour of carbohydrates at a nickel/carbon paper electrode with a novel fabrication method is investigated. The investigation is used for verification the feasibility of using monosaccharides and disaccharides in the application of fuel cell. The selected monosaccharides are glucose, fructose and galactose; the disaccharides are sucrose, maltose and lactose. The modified nickel/carbon paper electrode was prepared using a filtered cathodic vacuum arc technique. The morphology image of the nickel thin film on the carbon paper surface was characterized by scanning electron microscopy (SEM). The existence of nickel was verified by X-ray photoelectron spectroscopy (XPS). The contact angle measurement was also used to characterize the modified electrode. Cyclic voltammetry (CV) was employed to evaluate the electrochemical behaviour of monosaccharides and disaccharides in an alkaline aqueous solution. The modified electrode exhibits good electrocatalytic activities towards carbohydrates. In addition, the stability of the nickel/carbon paper electrode with six sugars was also investigated. The good catalytic effects of the nickel/carbon paper electrode allow for the use of carbohydrates as fuels in fuel cell applications

  10. Fabrication of nitrogen-containing diamond-like carbon film by filtered arc deposition as conductive hard-coating film

    Science.gov (United States)

    Iijima, Yushi; Harigai, Toru; Isono, Ryo; Imai, Takahiro; Suda, Yoshiyuki; Takikawa, Hirofumi; Kamiya, Masao; Taki, Makoto; Hasegawa, Yushi; Tsuji, Nobuhiro; Kaneko, Satoru; Kunitsugu, Shinsuke; Habuchi, Hitoe; Kiyohara, Shuji; Ito, Mikio; Yick, Sam; Bendavid, Avi; Martin, Phil

    2018-01-01

    Diamond-like carbon (DLC) films, which are amorphous carbon films, have been used as hard-coating films for protecting the surface of mechanical parts. Nitrogen-containing DLC (N-DLC) films are expected as conductive hard-coating materials. N-DLC films are expected in applications such as protective films for contact pins, which are used in the electrical check process of integrated circuit chips. In this study, N-DLC films are prepared using the T-shaped filtered arc deposition (T-FAD) method, and film properties are investigated. Film hardness and film density decreased when the N content increased in the films because the number of graphite structures in the DLC film increased as the N content increased. These trends are similar to the results of a previous study. The electrical resistivity of N-DLC films changed from 0.26 to 8.8 Ω cm with a change in the nanoindentation hardness from 17 to 27 GPa. The N-DLC films fabricated by the T-FAD method showed high mechanical hardness and low electrical resistivity.

  11. Ff-nano, Short Functionalized Nanorods Derived from Ff (f1, fd or M13 Filamentous Bacteriophage

    Directory of Open Access Journals (Sweden)

    Sadia eSattar

    2015-04-01

    Full Text Available F-specific filamentous phage of Escherichia coli (Ff: f1, M13 or fd are long thin filaments (860 nm x 6 nm. They have been a major workhorse in display technologies and bionanotechnology; however, some applications are limited by the high length-to-diameter ratio of Ff. Furthermore, use of functionalized Ff outside of laboratory containment is in part hampered by the fact that they are genetically modified viruses. We have now developed a system for production and purification of very short functionalized Ff-phage-derived nanorods, named Ff-nano, that are only 50 nm in length. In contrast to standard Ff-derived vectors that replicate in E. coli and contain antibiotic-resistance genes, Ff-nano are protein DNA complexes that cannot replicate on their own and do not contain any coding sequences. These nanorods show an increased resistance to heating at 70 °C in 1 % SDS in comparison to the full-length Ff phage of the same coat composition. We demonstrate that functionalized Ff-nano particles are suitable for application as detection particles in sensitive and quantitative dipstick lateral flow diagnostic assay for human plasma fibronectin.

  12. WE-F-16A-02: Design, Fabrication, and Validation of a 3D-Printed Proton Filter for Range Spreading

    International Nuclear Information System (INIS)

    Remmes, N; Courneyea, L; Corner, S; Beltran, C; Kemp, B; Kruse, J; Herman, M; Stoker, J

    2014-01-01

    Purpose: To design, fabricate and test a 3D-printed filter for proton range spreading in scanned proton beams. The narrow Bragg peak in lower-energy synchrotron-based scanned proton beams can result in longer treatment times for shallow targets due to energy switching time and plan quality degradation due to minimum monitor unit limitations. A filter with variable thicknesses patterned on the same scale as the beam's lateral spot size will widen the Bragg peak. Methods: The filter consists of pyramids dimensioned to have a Gaussian distribution in thickness. The pyramids are 2.5mm wide at the base, 0.6 mm wide at the peak, 5mm tall, and are repeated in a 2.5mm pseudo-hexagonal lattice. Monte Carlo simulations of the filter in a proton beam were run using TOPAS to assess the change in depth profiles and lateral beam profiles. The prototypes were constrained to a 2.5cm diameter disk to allow for micro-CT imaging of promising prototypes. Three different 3D printers were tested. Depth-doses with and without the prototype filter were then measured in a ~70MeV proton beam using a multilayer ion chamber. Results: The simulation results were consistent with design expectations. Prototypes printed on one printer were clearly unacceptable on visual inspection. Prototypes on a second printer looked acceptable, but the micro-CT image showed unacceptable voids within the pyramids. Prototypes from the third printer appeared acceptable visually and on micro-CT imaging. Depth dose scans using the prototype from the third printer were consistent with simulation results. Bragg peak width increased by about 3x. Conclusions: A prototype 3D printer pyramid filter for range spreading was successfully designed, fabricated and tested. The filter has greater design flexibility and lower prototyping and production costs compared to traditional ridge filters. Printer and material selection played a large role in the successful development of the filter

  13. WE-F-16A-02: Design, Fabrication, and Validation of a 3D-Printed Proton Filter for Range Spreading

    Energy Technology Data Exchange (ETDEWEB)

    Remmes, N; Courneyea, L; Corner, S; Beltran, C; Kemp, B; Kruse, J; Herman, M [Mayo Clinic, Rochester, MN (United States); Stoker, J [MD Anderson Cancer Center, Houston, TX (United States)

    2014-06-15

    Purpose: To design, fabricate and test a 3D-printed filter for proton range spreading in scanned proton beams. The narrow Bragg peak in lower-energy synchrotron-based scanned proton beams can result in longer treatment times for shallow targets due to energy switching time and plan quality degradation due to minimum monitor unit limitations. A filter with variable thicknesses patterned on the same scale as the beam's lateral spot size will widen the Bragg peak. Methods: The filter consists of pyramids dimensioned to have a Gaussian distribution in thickness. The pyramids are 2.5mm wide at the base, 0.6 mm wide at the peak, 5mm tall, and are repeated in a 2.5mm pseudo-hexagonal lattice. Monte Carlo simulations of the filter in a proton beam were run using TOPAS to assess the change in depth profiles and lateral beam profiles. The prototypes were constrained to a 2.5cm diameter disk to allow for micro-CT imaging of promising prototypes. Three different 3D printers were tested. Depth-doses with and without the prototype filter were then measured in a ~70MeV proton beam using a multilayer ion chamber. Results: The simulation results were consistent with design expectations. Prototypes printed on one printer were clearly unacceptable on visual inspection. Prototypes on a second printer looked acceptable, but the micro-CT image showed unacceptable voids within the pyramids. Prototypes from the third printer appeared acceptable visually and on micro-CT imaging. Depth dose scans using the prototype from the third printer were consistent with simulation results. Bragg peak width increased by about 3x. Conclusions: A prototype 3D printer pyramid filter for range spreading was successfully designed, fabricated and tested. The filter has greater design flexibility and lower prototyping and production costs compared to traditional ridge filters. Printer and material selection played a large role in the successful development of the filter.

  14. Mitigation action plan for 300-FF-1 remedial action

    International Nuclear Information System (INIS)

    Weiss, S.G.

    1996-10-01

    A record of decision was issued (dated July 1996), for remediation of waste sites in the 300-FF-1 Operable Unit in the 300 Area of the Hanford Site. The selected remedies for the 300-FF-1 and 300-FF-5 waste sites include selective excavation and disposal of contaminated soil and debris from the process waste units, excavation and removal of the 618-4 Burial Ground, and institutional controls for groundwater. This mitigation action plan explains how cultural resources will be managed and how revegetation for these remedial activities will be planned

  15. Design and fabrication of ultrathin silicon-nitride membranes for use in UV-visible airgap-based MEMS optical filters

    International Nuclear Information System (INIS)

    Ghaderi, Mohammadamir; Wolffenbuttel, Reinoud F.

    2016-01-01

    MEMS-based airgap optical filters are composed of quarter-wave thick high-index dielectric membranes that are separated by airgaps. The main challenge in the fabrication of these filters is the intertwined optical and mechanical requirements. The thickness of the layers decreases with design wavelength, which makes the optical performance in the UV more susceptible to fabrication tolerances, such as thickness and composition of the deposited layers, while the ability to sustain a certain level of residual stress by the structural strength becomes more critical. Silicon-nitride has a comparatively high Young's modulus and good optical properties, which makes it a suitable candidate as the membrane material. However, both the mechanical and optical properties in a silicon-nitride film strongly depend on the specifics of the deposition process. A design trade-off is required between the mechanical strength and the index of refraction, by tuning the silicon content in the silicon-nitride film. However, also the benefit of a high index of refraction in a silicon-rich film should be weighed against the increased UV optical absorption. This work presents the design, fabrication, and preliminary characterization of one and three quarter-wave thick silicon-nitride membranes with a one-quarter airgap and designed to give a spectral reflectance at 400 nm. The PECVD silicon-nitride layers were initially characterized, and the data was used for the optical and mechanical design of the airgap filters. A CMOS compatible process based on polysilicon sacrificial layers was used for the fabrication of the membranes. Optical characterization results are presented. (paper)

  16. Controllable liquid colour-changing lenses with microfluidic channels for vision protection, camouflage and optical filtering based on soft lithography fabrication.

    Science.gov (United States)

    Zhang, Min; Li, Songjing

    2016-01-01

    In this work, liquid colour-changing lenses for vision protection, camouflage and optical filtering are developed by circulating colour liquids through microfluidic channels on the lenses manually. Soft lithography technology is applied to fabricate the silicone liquid colour-changing layers with microfluidic channels on the lenses instead of mechanical machining. To increase the hardness and abrasion resistance of the silicone colour-changing layers on the lenses, proper fabrication parameters such as 6:1 (mass ration) mixing proportion and 100 °C curing temperature for 2 h are approved for better soft lithography process of the lenses. Meanwhile, a new surface treatment for the irreversible bonding of silicone colour-changing layer with optical resin (CR39) substrate lens by using 5 % (volume ratio) 3-Aminopropyltriethoxysilane solution is proposed. Vision protection, camouflage and optical filtering functions of the lenses are investigated with different designs of the channels and multi-layer structures. Each application can not only well achieve their functional demands, but also shows the advantages of functional flexibility, rapid prototyping and good controllability compared with traditional ways. Besides optometry, some other designs and applications of the lenses are proposed for potential utility in the future.

  17. SU-E-T-61: A Practical Process for Fabricating Passive Scatter Proton Beam Modulation Compensation Filters Using 3D Printing

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, T; Drzymala, R [Washington University School of Medicine, St. Louis, MO (United States)

    2015-06-15

    Purpose: The purpose of this project was to devise a practical fabrication process for passive scatter proton beam compensation filters (CF) that is competitive in time, cost and effort using 3D printing. Methods: DICOM compensator filter files for a proton beam were generated by our Eclipse (Varian, Inc.) treatment planning system. The compensator thickness specifications were extracted with in-house software written in Matlab (MathWorks, Inc.) code and written to a text file which could be read by the Rhinoceros 5, computer-aided design (CAD) package (Robert McNeel and Associates), which subsequently generated a smoothed model in a STereoLithographic also known as a Standard Tesselation Language file (STL). The model in the STL file was subsequently refined using Netfabb software and then converted to printing instructions using Cura. version 15.02.1. for our 3D printer. The Airwolf3D, model HD2x, fused filament fabrication (FFF) 3D printer (Airwolf3D.com) was used for our fabrication system with a print speed of 150mm per second. It can print in over 22 different plastic filament materials in a build volume of 11” x 8” x 12”. We choose ABS plastic to print the 3D model of the imprint for our CFs. Results: Prints of the CF could be performed at a print speed of 70mm per second. The time to print the 3D topology for the CF for the 14 cm diameter snout of our Mevion 250 proton accelerator was less than 3 hours. The printed model is intended to subsequently be used as a mold to imprint a molten wax cylindrical to form the compensation after cooling. The whole process should be performed for a typical 3 beam treatment plan within a day. Conclusion: Use of 3D printing is practical and can be used to print a 3D model of a CF within a few hours.

  18. SU-E-T-61: A Practical Process for Fabricating Passive Scatter Proton Beam Modulation Compensation Filters Using 3D Printing

    International Nuclear Information System (INIS)

    Zhao, T; Drzymala, R

    2015-01-01

    Purpose: The purpose of this project was to devise a practical fabrication process for passive scatter proton beam compensation filters (CF) that is competitive in time, cost and effort using 3D printing. Methods: DICOM compensator filter files for a proton beam were generated by our Eclipse (Varian, Inc.) treatment planning system. The compensator thickness specifications were extracted with in-house software written in Matlab (MathWorks, Inc.) code and written to a text file which could be read by the Rhinoceros 5, computer-aided design (CAD) package (Robert McNeel and Associates), which subsequently generated a smoothed model in a STereoLithographic also known as a Standard Tesselation Language file (STL). The model in the STL file was subsequently refined using Netfabb software and then converted to printing instructions using Cura. version 15.02.1. for our 3D printer. The Airwolf3D, model HD2x, fused filament fabrication (FFF) 3D printer (Airwolf3D.com) was used for our fabrication system with a print speed of 150mm per second. It can print in over 22 different plastic filament materials in a build volume of 11” x 8” x 12”. We choose ABS plastic to print the 3D model of the imprint for our CFs. Results: Prints of the CF could be performed at a print speed of 70mm per second. The time to print the 3D topology for the CF for the 14 cm diameter snout of our Mevion 250 proton accelerator was less than 3 hours. The printed model is intended to subsequently be used as a mold to imprint a molten wax cylindrical to form the compensation after cooling. The whole process should be performed for a typical 3 beam treatment plan within a day. Conclusion: Use of 3D printing is practical and can be used to print a 3D model of a CF within a few hours

  19. Development of a method for rapid and simultaneous monitoring of particulate and dissolved radiocesium in water with nonwoven fabric cartridge filters

    International Nuclear Information System (INIS)

    Hideki Tsuji; Tetsuo Yasutaka; Yoshihiko Kondo; Yasukazu Suzuki

    2014-01-01

    A method for the rapid and simultaneous monitoring of particulate and dissolved 137 Cs concentration in water was developed. This method uses pleated polypropylene nonwoven fabric filter to collect particulate radiocesium, and nonwoven fabric impregnated with Prussian blue (PB) to absorb dissolved radiocesium. The fabric was placed into cylindrical plastic cartridges (SS-cartridge and PB-cartridge). Traditional monitoring methods, such as evaporative concentration, often require time for pre-processing. However, this method described requires much less pre-processing time before the detection. Experiments conducted with simulated river water demonstrated that almost all of the suspended solids weight was collected in the SS-cartridge, and that more than 92 % of dissolved 137 Cs was absorbed onto the two PB-cartridges by 2.5 L/min flow rate when the range of the pH was 6-8. This device was applied to monitor Abukuma River water at two locations and the results were compared with those obtained using the filtrating and evaporative concentration method. The suspended solids concentration in river water, calculated by weight gain of the SS-cartridge and by sediment weight after filtration with a 0.45-μm membrane filter, agreed well. The radioactivity of the particulate and dissolved 137 Cs also agreed well in one of the two replications of this method. In addition, the required time for pre-processing was reduced by 60 times that by filtrating and evaporative concentration method. This method can separately collect and concentrate particulate and dissolved radiocesium rapidly and simultaneously in the field. (author)

  20. PASTURE ffPROVEMENT POSSIBILTTIES IN EFFECTIVE AI{IMAL ...

    African Journals Online (AJOL)

    PASTURE ffPROVEMENT POSSIBILTTIES IN EFFECTIVE AI{IMAL PRODUCTION SYSTEMS. P. de V. Booysen. University of Natal, King George V Avenue, Durban. (Key words: .... inherent in biotic simplification is the danger of increased susceptibility of the abiotic component to degradation. So as the agriculturalist ...

  1. FF. A package to evaluate one-loop Feynman diagrams

    International Nuclear Information System (INIS)

    Oldenborgh, G.J. van

    1990-09-01

    A short description and a user's guide of the FF package are given. This package contains routines to evaluate numerically the scalar one-loop integrals occurring in the evaluation in one-loop Feynman diagrams. The algorithms chosen are numerically stable over most parameter space. (author). 5 refs.; 1 tab

  2. LT COL F.F. PIENAAR'S BOER WAR DIARY

    African Journals Online (AJOL)

    LT COL F.F. PIENAAR'S BOER WAR DIARY. (PART II). Brig J.H. Picard, SM*. FREE STATE TO ..... bing up and down on his master's spare horse. ... Jantjie and his master turned out of the road, and ..... on a list which burghers could afford to.

  3. Acceptable knowledge summary report for combustible/noncombustible, metallic, and HEPA filter waste resulting from 238Pu fabrication activities

    International Nuclear Information System (INIS)

    Rogers, P.S.Z.; Foxx, C.L.

    1998-01-01

    All transuranic (TRU) waste must be sufficiently characterized and certified before it is shipped to the Waste Isolation Pilot Plant (WIPP). The US Environmental Protection Agency (EPA) allows use of acceptable knowledge (AK) for waste characterization. EPA uses the term AK in its guidance document and defines AK and provides guidelines on how acceptable knowledge should be obtained and documented. This AK package has been prepared in accordance with Acceptable Knowledge Documentation (TWCP-QP-1.1-021,R.2). This report covers acceptable knowledge information for five waste streams generated at TA-55 during operations to fabricate various heat sources using feedstock 238 Pu supplied by the Savannah River Site (SRS). The 238 Pu feedstock itself does not contain quantities of RCRA-regulated constituents above regulatory threshold limits, as known from process knowledge at SRS and as confirmed by chemical analysis. No RCRA-regulated chemicals were used during 238 Pu fabrication activities at TA-55, and all 238 Pu activities were physically separated from other plutonium processing activities. Most of the waste generated from the 238 Pu fabrication activities is thus nonmixed waste, including waste streams TA-55-43, 45, and 47. The exceptions are waste streams TA-55-44, which contains discarded lead-lined rubber gloves used in the gloveboxes that contained the 238 Pu material, and TA-55-46, which may contain pieces of discarded lead. These waste streams have been denoted as mixed because of the presence of the lead-containing material

  4. Suvekino pakub tummfilmi "Tartüff Live !" ja kontserti / Kristiina Vaarik

    Index Scriptorium Estoniae

    Vaarik, Kristiina

    2005-01-01

    8. septembril näidatakse Viljandi kultuurimaja hoovis saksa tummfilmi klassikasse kuuluvat Fr.W. Murnau filmi "Tartüff" (1925), mida saadab kohapeal Ardo Ran Varrese originaalmuusika "Tartüff live" ARV Ensemble esituses

  5. Environmental Control Plan for the 300-FF-1 Operable Unit Remedial Action

    International Nuclear Information System (INIS)

    Carlson, R.A.

    2000-01-01

    This environmental control plan is for the 300-FF-1 Operable Unit Remedial Action Project. The purpose of this plan is to identify environmental requirements for the 300-FF-1 operable unit Remedial Action/Waste Disposal Project

  6. Fragmentation of the radiation degraded chitosan by centrifugal filter and application of the fragmented chitosan in cotton fabrics finishing

    International Nuclear Information System (INIS)

    Luu Thi Tho; Nguyen Van Thong; Vu Thi Hong Khanh; Tran Minh Quynh

    2014-01-01

    Three kind of Vietnamese chitosans with the same deacetylation degrees of about 75% and viscosity average molecular weights are 69.000, 187.000 and 345.000 Da, respectively, were produced from shrimp shells and cuttle-bone at the MTV chitosan company (Kien Giang). These chitosans were irradiated at 25, 50, 75, 100, 200 and 500 kGy under Cobalt-60 gamma source at Hanoi Irradiation Center in order to prepare a series of chitosan segments with wide distribution of molecular weights. Different chitosan samples of the predetermined average molecular weight from 3,000 to 50,000 Da were separated from the irradiated chitosans by ultrafiltration with series of filter membranes (Centriprep devices). Molecular properties of the fragmented chitosans were analysed with gel permeation chromatography, Fourier transfer infra red spectrometry, and the results suggested that principal characteristics of chitosan were not affected by gamma irradiation, even its deacetylation degrees was increased. Solubility of the fragmented chitosans were much improved by radiation processing, and the chitosans having molecular weights below 5.000 Da were water-soluble polymers, which can easily apply as the auxiliary agent in textile. (author)

  7. Superhard nanocomposite nc-TiC/a-C:H film fabricated by filtered cathodic vacuum arc technique

    International Nuclear Information System (INIS)

    Wang Yaohui; Zhang Xu; Wu Xianying; Zhang Huixing; Zhang Xiaoji

    2008-01-01

    Superhard nanocomposite nc-TiC/a-C:H films, with an excellent combination of high elastic recovery, low friction coefficient and good H/E ratio, were prepared by filtered cathodic vacuum arc technique using the C 2 H 2 gas as the precursor. The effect of C 2 H 2 flow rate on the microstructure, phase composition, mechanical and tribological properties of nanocomposite nc-TiC/a-C:H films have been investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy disperse spectroscopy (EDS), microindentation and tribotester measurements. It was observed that the C 2 H 2 flow rate significantly affected the Ti content and hardness of films. Furthermore, by selecting the proper value for C 2 H 2 flow rate, 20 sccm, one can deposit the nanocomposite film nc-TiC/a-C:H with excellent properties such as superhardness (66.4 GPa), high elastic recovery (83.3%) and high H/E ratio (0.13)

  8. Remedial action and waste disposal project -- 300-FF-1 remedial action readiness assessment plan

    International Nuclear Information System (INIS)

    April, J.G.; Carlson, R.A.; Greif, A.A.; Johnson, C.R.; Orewiler, R.I.; Perry, D.M.; Plastino, J.C.; Roeck, F.V.; Tuttle, B.G.

    1997-04-01

    This Readiness Assessment Plan presents the methodology used to assess the readiness of the 300-FF-1 Remedial Action Project. Remediation involves the excavation, treatment if applicable, and final disposal of contaminated soil and debris associated with the waste sites in the 300-FF-1 Operable Unit. The scope of the 300-FF-1 remediation is to excavate, transport, and dispose of contaminated solid from sites identified in the 300-FF-1 Operable Unit

  9. Immobilized Filters for Air Filtration

    National Research Council Canada - National Science Library

    Mahle, John J; Zaiee, Saeed

    2002-01-01

    ... (settling performance) and attrition resistance. The fabricated filter samples will be analyzed in order to determine the physical and chemical factors affecting mechanical strength and chemical filtration...

  10. Fuzzy filter for state estimation of a glucoregulatory system.

    Science.gov (United States)

    Trajanoski, Z; Wach, P

    1996-08-01

    A filter based on fuzzy logic for state estimation of a glucoregulatory system is presented. A published non-linear model for the dynamics of glucose and its hormonal control including a single glucose compartment, five insulin compartments and a glucagon compartment was used for simulation. The simulated data were corrupted by an additive white noise with zero mean and a coefficient of variation (CV) of between 2 and 20% and then submitted to the state estimation procedure using a fuzzy filter (FF). The performance of the FF was compared with an extended Kalman filter (EKF) for state estimation. Both the FF and the EKF were evaluated in the following cases: (a) five state variables are measurable; three plasma variables are measurable; only plasma glucose is measurable; (b) for different measurement noise levels (CV of 2-20%); and (c) a mismatch between the glucoregulatory system and the given mathematical model (uncertain or approximate model). In contrast to the FF, in the case of approximate model of the glucose system, the EKF failed to achieve useful state estimation. Moreover, the performance of the FF was independent of the noise level. In conclusion, the FF approach is a viable alternative for state estimation in a noisy environment and with an uncertain mathematical model of the glucoregulatory system.

  11. Phase I remedial investigation report for the 300-FF-5 operable unit, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-01-01

    The focus of this remedial investigation (RI) is the 300-FF-5 operable unit, one of five operable units associated with the 300 Area aggregate of the U.S. Department of Energy`s (DOE`s) Hanford Site. The 300-FF-5 operable unit is a groundwater operable unit beneath the 300-FF-1, 300-FF-2, and 300-FF-3 source operable units. This operable unit was designated to include all contamination detected in the groundwater and sediments below the water table that emanates from the 300-FF-1, 300-FF-2, and 300-FF-3 operable units (DOE-RL 1990a). In November 1989, the U.S. Environmental Protection Agency (EPA) placed the 300 Area on the National Priorities List (NPL) contained within Appendix B of the National Oil and Hazardous Substance Pollution Contingency Plan (NCP, 53 FR 51391 et seq.). The EPA took this action pursuant to their authority under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA, 42 USC 9601 et seq.). The DOE Richland Operations Office (DOE-RL), the EPA and Washington Department of Ecology (Ecology) issued the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement), in May 1989 (Ecology et al. 1992, Rev. 2). This agreement, among other matters, governs all CERCLA efforts at the Hanford Site. In June 1990, a remedial investigation/feasibility study (RI/FS) workplan for the 300-FF-5 operable unit was issued pursuant to the Tri-Party Agreement.

  12. Phase I remedial investigation report for the 300-FF-5 operable unit, Volume 1

    International Nuclear Information System (INIS)

    1994-01-01

    The focus of this remedial investigation (RI) is the 300-FF-5 operable unit, one of five operable units associated with the 300 Area aggregate of the U.S. Department of Energy's (DOE's) Hanford Site. The 300-FF-5 operable unit is a groundwater operable unit beneath the 300-FF-1, 300-FF-2, and 300-FF-3 source operable units. This operable unit was designated to include all contamination detected in the groundwater and sediments below the water table that emanates from the 300-FF-1, 300-FF-2, and 300-FF-3 operable units (DOE-RL 1990a). In November 1989, the U.S. Environmental Protection Agency (EPA) placed the 300 Area on the National Priorities List (NPL) contained within Appendix B of the National Oil and Hazardous Substance Pollution Contingency Plan (NCP, 53 FR 51391 et seq.). The EPA took this action pursuant to their authority under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA, 42 USC 9601 et seq.). The DOE Richland Operations Office (DOE-RL), the EPA and Washington Department of Ecology (Ecology) issued the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement), in May 1989 (Ecology et al. 1992, Rev. 2). This agreement, among other matters, governs all CERCLA efforts at the Hanford Site. In June 1990, a remedial investigation/feasibility study (RI/FS) workplan for the 300-FF-5 operable unit was issued pursuant to the Tri-Party Agreement

  13. The effect of FF-MAS on porcine cumulus-oocyte complex maturation, fertilization and pronucleus formation in vitro

    DEFF Research Database (Denmark)

    Færge, Inger; Strejcek, Frantisek; Laurincik, Jozef

    2006-01-01

    mechanically using a fine glass pipette under constant pH and in vitro fertilized with fresh semen (5 x 105 spermatozoa/ml). The presumptive zygotes were evaluated 18 h after fertilization. The addition of pFF increased the monospermic as well as the polyspermic penetration of oocytes. In the absence of p......FF, the addition of FF-MAS decreased the polyspermic penetration rate, wehreas FF-MAS in combination with pFF decreased monospermic and increased polyspermic penetration. The degeneration rate of ova decreased in the presence of FF-MAS irrespective of the presence or absence of pFF. In the absence of pFF, FF...

  14. Fabrication of recyclable superhydrophobic cotton fabrics

    Science.gov (United States)

    Han, Sang Wook; Park, Eun Ji; Jeong, Myung-Geun; Kim, Il Hee; Seo, Hyun Ook; Kim, Ju Hwan; Kim, Kwang-Dae; Kim, Young Dok

    2017-04-01

    Commercial cotton fabric was coated with SiO2 nanoparticles wrapped with a polydimethylsiloxane (PDMS) layer, and the resulting material surface showed a water contact angle greater than 160°. The superhydrophobic fabric showed resistance to water-soluble contaminants and maintained its original superhydrophobic properties with almost no alteration even after many times of absorption-washing cycles of oil. Moreover, superhydrophobic fabric can be used as a filter to separate oil from water. We demonstrated a simple method of fabrication of superhydrophobic fabric with potential interest for use in a variety of applications.

  15. Effect of 905 MHz microwave radiation on colony growth of the yeast Saccharomyces cerevisiae strains FF18733, FF1481 and D7

    International Nuclear Information System (INIS)

    Vrhovac, Ivana; Hrascan, Reno; Franekic, Jasna

    2010-01-01

    The aim of this study was to evaluate the effect of weak radiofrequency microwave (RF/MW) radiation emitted by mobile phones on colony growth of the yeast Saccharomyces cerevisiae. S. cerevisiae strains FF18733 (wild-type), FF1481 (rad1 mutant) and D7 (commonly used to detect reciprocal and nonreciprocal mitotic recombinations) were exposed to a 905 MHz electromagnetic field that closely matched the Global System for Mobile Communication (GSM) pulse modulation signals for mobile phones at a specific absorption rate (SAR) of 0.12 W/kg. Following 15-, 30- and 60-minutes exposure to RF/MW radiation, strain FF18733 did not show statistically significant changes in colony growth compared to the control sample. The irradiated strains FF1481 and D7 demonstrated statistically significant reduction of colony growth compared to non-irradiated strains after all exposure times. Furthermore, strain FF1481 was more sensitive to RF/MW radiation than strain D7. The findings indicate that pulsed RF/MW radiation at a low SAR level can affect the rate of colony growth of different S. cerevisiae strains

  16. 300-FF-1 remedial action sampling and analysis plan DQO process summary report

    International Nuclear Information System (INIS)

    Carlson, R.A.

    1997-01-01

    The scope of the 300-FF-1 Operable Unit (OU) data quality objective (DQO) process includes the soil and debris from the waste sites identified in the Proposed Plan for the 300-FF-1 and 300-FF-5 Operable units and, as the DQO process evolved, refined by the 300-FF-1 Record of Decision (ROD). Exclusions are identified in Section 1.3. The 300-FF-1 waste sites are addressed throughout the DQO process as they were subdivided in the proposed plan. The waste sites are divided into areas or zones known to be above the cleanup standards, zones below the cleanup standards, and zones where the contamination level is currently unknown. The project objectives are (1) to identify the criteria by which 300-FF-1 contaminated soil and debris may be shipped to the Environmental Restoration Disposal Facility (ERDF), (2) to identify the criteria by which the 300-FF-1 waste sites can be demonstrated as meeting the cleanup criteria, and (3) to develop a sampling and analysis plan (SAP) that adequately allows the evaluation of soil and debris analysis against the criteria

  17. Survey Method for Radiological Surveys of 300-FF-1 Operable Unit Soils and Material

    International Nuclear Information System (INIS)

    Brehm, D.M.

    1998-06-01

    This technical basis is to be used to survey soils at the 300-FF-1 Operable Unit during remediation of the site. Its purpose is to provide a basis for the survey methods to be employed by radiological control technician (RCTs) to guide the excavation effort in accordance with the 300-FF-1 waste site Record of Decision (ROD). The ROD for the 300-FF-1 Operable Unit requires selective excavation, removal, and disposal of contaminated soil above 350 pCi/g total uranium activity. Soil above this level will be disposed of as radioactive waste. The remaining soil will remain onsite

  18. Remedial action and waste disposal project -- 300-FF-1 remedial action readiness assessment report

    International Nuclear Information System (INIS)

    Carson, J.W.; Carlson, R.A.; Greif, A.A.; Johnson, C.R.; Orewiler, R.I.; Perry, D.M.; Remsen, W.E.; Tuttle, B.G.; Wilson, R.C.

    1997-09-01

    This report documents the readiness assessment for initial startup of the 300-FF-1 Remedial Action Task. A readiness assessment verifies and documents that field activities are ready to start (or restart) safely. The 300-FF-1 assessment was initiated in April 1997. Readiness assessment activities included confirming the completion of project-specific procedures and permits, training staff, obtaining support equipment, receipt and approval of subcontractor submittals, and mobilization and construction of site support systems. The scope of the 300-FF-1 Remedial Action Task includes excavation and disposal of contaminated soils at liquid waste disposal facilities and of waste in the 618-4 Burial Ground and the 300-FF-1 landfills. The scope also includes excavation of test pits and test trenches

  19. Soil washing physical separations test procedure - 300-FF-1 operable unit

    Energy Technology Data Exchange (ETDEWEB)

    Belden, R.D.

    1993-10-08

    This procedure provides the operations approach, a field sampling plan, and laboratory procedures for a soil washing test to be conducted by Alternative Remedial Technologies, Inc. (ART) in the 300-FF-1 area at the Hanford site. The {open_quotes}Quality Assurance Project Plan for the Soil Washing Physical Separations Test, 300-FF-1 Operable Unit,{close_quotes} Hanford, Washington, Alternative Remedial Technologies, Inc., February 1994 (QAPP) is provided in a separate document that presents the procedural and organizational guidelines for this test. This document describes specifications, responsibilities, and general procedures to be followed to conduct physical separation soil treatability tests in the North Process Pond of the 300-FF-1 Operable Unit (OU) at the Hanford Site. These procedures are based on the {open_quotes}300-FF-1 Physical Separations CERCLA Treatability Test Plan, DOE/RL 92-2l,{close_quotes} (DOE-RL 1993).

  20. Soil washing physical separations test procedure - 300-FF-1 operable unit

    International Nuclear Information System (INIS)

    Belden, R.D.

    1993-01-01

    This procedure provides the operations approach, a field sampling plan, and laboratory procedures for a soil washing test to be conducted by Alternative Remedial Technologies, Inc. (ART) in the 300-FF-1 area at the Hanford site. The open-quotes Quality Assurance Project Plan for the Soil Washing Physical Separations Test, 300-FF-1 Operable Unit,close quotes Hanford, Washington, Alternative Remedial Technologies, Inc., February 1994 (QAPP) is provided in a separate document that presents the procedural and organizational guidelines for this test. This document describes specifications, responsibilities, and general procedures to be followed to conduct physical separation soil treatability tests in the North Process Pond of the 300-FF-1 Operable Unit (OU) at the Hanford Site. These procedures are based on the open-quotes 300-FF-1 Physical Separations CERCLA Treatability Test Plan, DOE/RL 92-2l,close quotes (DOE-RL 1993)

  1. Operation and Maintenance Plan for the 300-FF-5 Operable Unit

    International Nuclear Information System (INIS)

    Singleton, K.M.

    1996-09-01

    This document is the operation and maintenance plan for the 300-FF-5 groundwater operable unit. The purpose of this plan is to identify tasks necessary to verify the effectiveness of the selected alternative. This plan also describes the monitoring program and administrative tasks that will be used as the preferred alternative for the remediation of groundwater in the 300-FF-5 Operable Unit. The preferred alternative selected for remediation of groundwater consists of institutional controls

  2. Gamma-ray imaging and holdup assays of 235-F PuFF cells 1 & 2

    Energy Technology Data Exchange (ETDEWEB)

    Aucott, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-12-20

    Savannah River National Laboratory (SRNL) Nuclear Measurements (L4120) was tasked with performing enhanced characterization of the holdup in the PuFF shielded cells. Assays were performed in accordance with L16.1-ADS-2460 using two high-resolution gamma-ray detectors. The first detector, an In Situ Object Counting System (ISOCS)-characterized detector, was used in conjunction with the ISOCS Geometry Composer software to quantify grams of holdup. The second detector, a Germanium Gamma-ray Imager (GeGI), was used to visualize the location and relative intensity of the holdup in the cells. Carts and collimators were specially designed to perform optimum assays of the cells. Thick, pencil-beam tungsten collimators were fabricated to allow for extremely precise targeting of items of interest inside the cells. Carts were designed with a wide range of motion to position and align the detectors. A total of 24 measurements were made, each typically 24 hours or longer to provide sufficient statistical precision. This report presents the results of the enhanced characterization for cells 1 and 2. The measured gram values agree very well with results from the 2014 study. In addition, images were created using both the 2014 data and the new GeGI data. The GeGI images of the cells walls reveal significant Pu-238 holdup on the surface of the walls in cells 1 and 2. Additionally, holdup is visible in the two pass-throughs from cell 1 to the wing cabinets. This report documents the final element (exterior measurements coupled with gamma-ray imaging and modeling) of the enhanced characterization of cells 1-5 (East Cell Line).

  3. Structural shielding design of a 6 MV flattening filter free linear accelerator: Indian scenario

    Directory of Open Access Journals (Sweden)

    Bibekananda Mishra

    2017-01-01

    Full Text Available Detailed structural shielding of primary and secondary barriers for a 6 MV medical linear accelerator (LINAC operated with flattening filter (FF and flattening filter free (FFF modes are calculated. The calculations have been carried out by two methods, one using the approach given in National Council on Radiation Protection (NCRP Report No. 151 and the other based on the monitor units (MUs delivered in clinical practice. Radiation survey of the installations was also carried out. NCRP approach suggests that the primary and secondary barrier thicknesses are higher by 24% and 26%. respectively, for a LINAC operated in FF mode to that of a LINAC operated in both FF and FFF modes with an assumption that only 20% of the workload is shared in FFF mode. Primary and secondary barrier thicknesses calculated from MUs delivered on clinical practice method also show the same trend and are higher by 20% and 19%, respectively, for a LINAC operated in FF mode to that of a LINAC operated in both FF and FFF modes. Overall, the barrier thickness for a LINAC operated in FF mode is higher about 20% to that of a LINAC operated in both FF and FFF modes.

  4. Structural Shielding Design of a 6 MV Flattening Filter Free Linear Accelerator: Indian Scenario.

    Science.gov (United States)

    Mishra, Bibekananda; Selvam, T Palani; Sharma, P K Dash

    2017-01-01

    Detailed structural shielding of primary and secondary barriers for a 6 MV medical linear accelerator (LINAC) operated with flattening filter (FF) and flattening filter free (FFF) modes are calculated. The calculations have been carried out by two methods, one using the approach given in National Council on Radiation Protection (NCRP) Report No. 151 and the other based on the monitor units (MUs) delivered in clinical practice. Radiation survey of the installations was also carried out. NCRP approach suggests that the primary and secondary barrier thicknesses are higher by 24% and 26%. respectively, for a LINAC operated in FF mode to that of a LINAC operated in both FF and FFF modes with an assumption that only 20% of the workload is shared in FFF mode. Primary and secondary barrier thicknesses calculated from MUs delivered on clinical practice method also show the same trend and are higher by 20% and 19%, respectively, for a LINAC operated in FF mode to that of a LINAC operated in both FF and FFF modes. Overall, the barrier thickness for a LINAC operated in FF mode is higher about 20% to that of a LINAC operated in both FF and FFF modes.

  5. SU-E-T-311: Dosimetric Comparison of Volumetric Modulated Arc Therapy Plans for Preoperative Radiotherapy Rectal Cancer Using Flattening Filter-Free and Flattening Filter Modes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, W; Zhang, J; Lu, J; Chen, C [Cancer Hospital of Shantou University Medical College, Shantou, Guangdong (China)

    2015-06-15

    Purpose: To compare the dosimetric difference of volumetric modulated arc therapy(VMAT) for preoperative radiotherapy rectal cancer using 6MV X-ray flattening filter free(FFF) and flattening filter(FF) modes. Methods: FF-VMAT and FFF-VMAT plans were designed to 15 rectal cancer patients with preoperative radiotherapy by planning treatment system(Eclipse 10.0),respectively. Dose prescription was 50 Gy in 25 fractions. All plans were normalized to 50 Gy to 95% of PTV. The Dose Volume Histogram (DVH), target and risk organ doses, conformity indexes (CI), homogeneity indexes (HI), low dose volume of normal tissue(BP), monitor units(MU) and treatment time (TT) were compared between the two kinds of plans. Results: FF-VMAT provided the lower Dmean, V105, HI, and higher CI as compared with FFF-VMAT. The small intestine of D5, Bladder of D5, Dmean, V40, V50, L-femoral head of V40, R-femoral head of Dmean were lower in FF-VMAT than in FFF-VMAT. FF-VMAT had higher BP of V5, but no significantly different of V10, V15, V20, V30 as compared with FFF-VMAT. FF-VMAT reduceed the monitor units(MU) by 21%(P<0.05), as well as the treatment time(TT) was no significantly different(P>0.05), as compared with FFF-VMAT. Conclusion: The plan qualities of FF and FFF VMAT plans were comparable and both clinically acceptable. FF-VMAT as compared with FFF-VMAT, showing better target coverage, some of OARs sparing, the MUs of FFF-VMAT were higher than FF-VMAT, yet were delivered within the same time. This work was supported by the Medical Scientific Research Foundation of Guangdong Procvince (A2014455 to Changchun Ma)

  6. Beam Characterization of 10-MV Photon Beam from Medical Linear Accelerator without Flattening Filter.

    Science.gov (United States)

    Shimozato, Tomohiro; Aoyama, Yuichi; Matsunaga, Takuma; Tabushi, Katsuyoshi

    2017-01-01

    This work investigated the dosimetric properties of a 10-MV photon beam emitted from a medical linear accelerator (linac) with no flattening filter (FF). The aim of this study is to analyze the radiation fluence and energy emitted from the flattening filter free (FFF) linac using Monte Carlo (MC) simulations. The FFF linac was created by removing the FF from a linac in clinical use. Measurements of the depth dose (DD) and the off-axis profile were performed using a three-dimensional water phantom with an ionization chamber. A MC simulation for a 10-MV photon beam from this FFF linac was performed using the BEAMnrc code. The off-axis profiles for the FFF linac exhibited a chevron-like distribution, and the dose outside the irradiation field was found to be lower for the FFF linac than for a linac with an FF (FF linac). The DD curves for the FFF linac included many contaminant electrons in the build-up region. Therefore, for clinical use, a metal filter is additionally required to reduce the effects of the electron contamination. The mean energy of the FFF linac was found to be lower than that of the FF linac owing to the absence of beam hardening caused by the FF.

  7. Hybrid Filter Membrane

    Science.gov (United States)

    Laicer, Castro; Rasimick, Brian; Green, Zachary

    2012-01-01

    Cabin environmental control is an important issue for a successful Moon mission. Due to the unique environment of the Moon, lunar dust control is one of the main problems that significantly diminishes the air quality inside spacecraft cabins. Therefore, this innovation was motivated by NASA s need to minimize the negative health impact that air-suspended lunar dust particles have on astronauts in spacecraft cabins. It is based on fabrication of a hybrid filter comprising nanofiber nonwoven layers coated on porous polymer membranes with uniform cylindrical pores. This design results in a high-efficiency gas particulate filter with low pressure drop and the ability to be easily regenerated to restore filtration performance. A hybrid filter was developed consisting of a porous membrane with uniform, micron-sized, cylindrical pore channels coated with a thin nanofiber layer. Compared to conventional filter media such as a high-efficiency particulate air (HEPA) filter, this filter is designed to provide high particle efficiency, low pressure drop, and the ability to be regenerated. These membranes have well-defined micron-sized pores and can be used independently as air filters with discreet particle size cut-off, or coated with nanofiber layers for filtration of ultrafine nanoscale particles. The filter consists of a thin design intended to facilitate filter regeneration by localized air pulsing. The two main features of this invention are the concept of combining a micro-engineered straight-pore membrane with nanofibers. The micro-engineered straight pore membrane can be prepared with extremely high precision. Because the resulting membrane pores are straight and not tortuous like those found in conventional filters, the pressure drop across the filter is significantly reduced. The nanofiber layer is applied as a very thin coating to enhance filtration efficiency for fine nanoscale particles. Additionally, the thin nanofiber coating is designed to promote capture of

  8. Performance of non woven synthetic fabric and disc filters for fertirrigation water treatment Desempenho dos filtros de mantas não tecidas e de disco no tratamento de água para fertirrigação

    Directory of Open Access Journals (Sweden)

    Túlio Assunção Pires Ribeiro

    2004-04-01

    Full Text Available Obstruction of emitters caused by the presence of solid particles in the water raises the cost and maintenance of trickle irrigation systems, and might compromise their utilization. This research was performed through test fields, with the objective of evaluating the performance of a disc filter (130 microns and a non woven synthetic fabric filter on the removal of physical, chemical and biological impurities from the irrigation water, which may cause emitter obstruction during fertirrigation processes. The evaluation criteria of the impurities present in the irrigation water, were based on studies performed on trickle irrigation systems. Specifically, physical, chemical and biological parameters analyzed in the inflow and outflow water from both filters were: pH, turbidity, total suspended solids, salinity, total iron, sulphites, manganese, algae and bacteria. Results pointed to chemical factors, which presented medium clogging risks to the emitters; those factors were: pH, total iron and sulphite concentration. All the other parameters of water quality did not present clogging risks. A comparative analysis of head loss evolution, according to the filtered volume, was also atempted Non woven synthetic fabric filter presented a higher evolution when compared to the disc filter.Um dos fatores que elevam os custos de operação e manutenção dos sistemas de irrigação localizada e, em certos casos, inviabiliza a utilização desse método, é a obstrução de emissores pela presença de partículas sólidas na água de irrigação. O presente trabalho teve por objetivo principal estimar, através de ensaios experimentais de campo, o desempenho de um filtro de disco (130 microns com outro de manta sintética não tecida na remoção de impurezas de origens físicas, químicas e biológicas presentes na água de irrigação que promovem o entupimento dos emissores, quando se utiliza a fertirrigação. Os critérios para avaliação das impurezas

  9. Dosimetric evaluation of fattening filter free photon beams

    International Nuclear Information System (INIS)

    Lechner, W.

    2014-01-01

    Very recently, conventional treatment machines able to deliver flattening filter free photon have been introduced into clinical practice. An Elekta Pricise linear accelerator LINAC which was able to deliver 6MV and 10 MV flattened (FF) and flattening filter free (FFF) photon beams was used throughout this work. The investigated modalities were 9-Field intensity modulated radiotherapy (Intensity modulated radiotherapy (IMRT)) and 360° - single arc volumetric modulated arc therapy (Volumetric modulated arc therapy (VMAT)) with flattened and unflattened photon beams. For treatment plan evaluation the concept of Pareto optimal fronts was employed. Additionally, the efficiency of these modalities was assessed. The evaluation of the treatment plan quality showed no significant difference between FF- and FFF-beams. With respect to treatment plan efficiency, a significant decrease of delivery time of IMRT treatment plans without flattening filter compared to those with filter was found. On average, the delivery time decreased by 18% and 4% for prostate and head-and-neck cases, respectively. In contrast to that, the delivery time of VMAT treatment plans without flatting filter was significantly increased by 22% and 16% for prostate and head- and-neck cases, respectively. The applicability of 14 different detectors to small field dosimetry in FF- as well as in FFF-beams was investigated by measuring output factors of 6MV and 10 MV FF- and FFF- beams. An additional MLC was attached to the treatment machine in order to generate field sizes between 0.6x0.6 cm 2 and 10x10 cm 2 . Alanine pellets were used as reference detectors for the calculation of correction factors for small field dosimetry. Compared to alanine, the solid sate detectors and the liquid filled ionization chamber generally overestimated the output factors of small fields, whereas the air filled ionzation chambers underestimated the output factors. For the shielded diodes the correction factors ranged between 8

  10. Temporary septic holding tank at the 300-FF-1 remedial action central support facility -- Engineering report

    International Nuclear Information System (INIS)

    Jackson, G.J.

    1996-09-01

    The 300-FF-1 Remedial Action Support Facility will be required in the 300 Area (at the Hanford Site in Richland, Washington) to support the remedial actions planned for the 300-FF-1 Operable Unit. In conjunction with this project, soils laden with radiological contamination will be excavated, removed, and transported to a permitted disposal facility, if required based upon characterization. This facility will be a temporary, modular building sized to provide office and work space for the supervisors, engineers, and technicians assigned to the project and engaged in the associated field work. Electrical and potable water service to the 300-FF-1 Support Facility will be provided via permanent connections to existing systems. A temporary septic system is desired as opposed to connecting to the existing sewer system due to regulatory issues. The paper describes the project location, geology and flooding potential, design criteria, operations, and maintenance

  11. Filter arrays

    Science.gov (United States)

    Page, Ralph H.; Doty, Patrick F.

    2017-08-01

    The various technologies presented herein relate to a tiled filter array that can be used in connection with performance of spatial sampling of optical signals. The filter array comprises filter tiles, wherein a first plurality of filter tiles are formed from a first material, the first material being configured such that only photons having wavelengths in a first wavelength band pass therethrough. A second plurality of filter tiles is formed from a second material, the second material being configured such that only photons having wavelengths in a second wavelength band pass therethrough. The first plurality of filter tiles and the second plurality of filter tiles can be interspersed to form the filter array comprising an alternating arrangement of first filter tiles and second filter tiles.

  12. 300-FF-1 remedial design report/remedial action work plan

    International Nuclear Information System (INIS)

    Gustafson, F.W.

    1997-02-01

    The 300 Area has been divided into three operable units 300-FF-1, 300-FF-2, and 300-FF-5 all of which are in various stages of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) process. The 300-FF-1 Operable Unit, the subject of this report, includes liquid waste disposal sites, landfills, and a burial ground. This Remedial Design Report/Remedial Action Work Plan (RDR/RAWP) provides a summary description of each waste site included in the 300-FF-1 Operable Unit, the basis for remedial actions to be taken, and the remedial action approach and management process for implementing these actions. The remedial action approach and management sections provide a description of the remedial action process description, the project schedule, the project team, required planning documentation, the remedial action change process, the process for verifying attainment of the remedial action goals, and the required CERCLA and RCRA closeout documentation. Appendix A provides additional details on each waste site. In addition to remediation of the waste sites, waste generated during the remedial investigation/feasibility study portions of the project will also be disposed at the Environmental Restoration Disposal Facility (ERDF). Appendix B provides a summary of the modeling performed in the 300-FF-1 Phase 3 FS and a description of the modeling effort to be used to show attainment of the remedial action goals. Appendix C provides the sampling and analysis plan (SAP) for all sampling and field-screening activities performed during remediation and for verification of attainment with the remedial action goals. Appendix D provides the public involvement plan, prepared to ensure information is provided to the public during remedial design and remedial action processes

  13. Algorithms of GPU-enabled reactive force field (ReaxFF) molecular dynamics.

    Science.gov (United States)

    Zheng, Mo; Li, Xiaoxia; Guo, Li

    2013-04-01

    Reactive force field (ReaxFF), a recent and novel bond order potential, allows for reactive molecular dynamics (ReaxFF MD) simulations for modeling larger and more complex molecular systems involving chemical reactions when compared with computation intensive quantum mechanical methods. However, ReaxFF MD can be approximately 10-50 times slower than classical MD due to its explicit modeling of bond forming and breaking, the dynamic charge equilibration at each time-step, and its one order smaller time-step than the classical MD, all of which pose significant computational challenges in simulation capability to reach spatio-temporal scales of nanometers and nanoseconds. The very recent advances of graphics processing unit (GPU) provide not only highly favorable performance for GPU enabled MD programs compared with CPU implementations but also an opportunity to manage with the computing power and memory demanding nature imposed on computer hardware by ReaxFF MD. In this paper, we present the algorithms of GMD-Reax, the first GPU enabled ReaxFF MD program with significantly improved performance surpassing CPU implementations on desktop workstations. The performance of GMD-Reax has been benchmarked on a PC equipped with a NVIDIA C2050 GPU for coal pyrolysis simulation systems with atoms ranging from 1378 to 27,283. GMD-Reax achieved speedups as high as 12 times faster than Duin et al.'s FORTRAN codes in Lammps on 8 CPU cores and 6 times faster than the Lammps' C codes based on PuReMD in terms of the simulation time per time-step averaged over 100 steps. GMD-Reax could be used as a new and efficient computational tool for exploiting very complex molecular reactions via ReaxFF MD simulation on desktop workstations. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. 300-FF-1 remedial design report/remedial action work plan

    Energy Technology Data Exchange (ETDEWEB)

    Gustafson, F.W.

    1997-02-01

    The 300 Area has been divided into three operable units 300-FF-1, 300-FF-2, and 300-FF-5 all of which are in various stages of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) process. The 300-FF-1 Operable Unit, the subject of this report, includes liquid waste disposal sites, landfills, and a burial ground. This Remedial Design Report/Remedial Action Work Plan (RDR/RAWP) provides a summary description of each waste site included in the 300-FF-1 Operable Unit, the basis for remedial actions to be taken, and the remedial action approach and management process for implementing these actions. The remedial action approach and management sections provide a description of the remedial action process description, the project schedule, the project team, required planning documentation, the remedial action change process, the process for verifying attainment of the remedial action goals, and the required CERCLA and RCRA closeout documentation. Appendix A provides additional details on each waste site. In addition to remediation of the waste sites, waste generated during the remedial investigation/feasibility study portions of the project will also be disposed at the Environmental Restoration Disposal Facility (ERDF). Appendix B provides a summary of the modeling performed in the 300-FF-1 Phase 3 FS and a description of the modeling effort to be used to show attainment of the remedial action goals. Appendix C provides the sampling and analysis plan (SAP) for all sampling and field-screening activities performed during remediation and for verification of attainment with the remedial action goals. Appendix D provides the public involvement plan, prepared to ensure information is provided to the public during remedial design and remedial action processes.

  15. SU-E-T-153: Burst-Mode Modulated Arc Therapy with Flattening-Filter-Free Beams Versus Flattening-Filtered Beams

    Energy Technology Data Exchange (ETDEWEB)

    Kainz, K; Lawton, C; Li, X [Medical College of Wisconsin, Milwaukee, WI (United States)

    2015-06-15

    Purpose: To compare the dosimetry and delivery of burst-mode modulated arc radiotherapy using flattening-filter-free (FFF) and flattening-filtered (FF) beams. Methods: Burst-mode modulated arc therapy (mARC, Siemens) plans were generated for six prostate cases with FFF and FF beam models, using the Elekta Monaco v. 5.00 planning system. One 360-degree arc was used for five cases, and for one case two 360-degree coplanar arcs were used. The maximum number of optimization points (OPs) per arc was set to 91, and OPs with less than 4 MU were disregarded. All plans were delivered on the Siemens Artiste linear accelerator with 6MV FF (300 MU/min) and comparable-energy FFF (2000 MU/min, labeled as 7UF) beams. Results: For all cases studied, the plans with FFF beams exhibited DVHs for the PTV, rectum, and bladder that were nearly identical to those for the plans with FF beams. The FFF plan yielded reduced dose to the right femoral head for 5 cases, and lower mean dose to the left femoral head for 4 cases. For all but the two-arc case, the FFF and FF plans resulted in an identical number of segments. The total number of MUs was slightly lower for the FF plans for five cases. The total delivery time per fraction was substantially lower for the FFF plans, ranging from 25 to 50 percent among all cases, as compared to the FF plans. Conclusion: For mARC plans, FFF and FF beams provided comparable PTV coverage and rectum and bladder sparing. For the femoral heads, the mean dose was slightly lower in most cases when using the FFF beam. Although the flat beam plans typically required slightly fewer MUs, FFF beams required substantially less time to deliver a plan of similar quality. This work was supported by Siemens Medical Solutions and the MCW Cancer Center Fotsch Foundation.

  16. Tunable electro-optic filter stack

    Science.gov (United States)

    Fontecchio, Adam K.; Shriyan, Sameet K.; Bellingham, Alyssa

    2017-09-05

    A holographic polymer dispersed liquid crystal (HPDLC) tunable filter exhibits switching times of no more than 20 microseconds. The HPDLC tunable filter can be utilized in a variety of applications. An HPDLC tunable filter stack can be utilized in a hyperspectral imaging system capable of spectrally multiplexing hyperspectral imaging data acquired while the hyperspectral imaging system is airborne. HPDLC tunable filter stacks can be utilized in high speed switchable optical shielding systems, for example as a coating for a visor or an aircraft canopy. These HPDLC tunable filter stacks can be fabricated using a spin coating apparatus and associated fabrication methods.

  17. UV Bandpass Optical Filter for Microspectometers

    NARCIS (Netherlands)

    Correia, J.H.; Emadi, A.R.; Wolffenbuttel, R.F.

    2006-01-01

    This paper describes the design and modeling of a UV bandpass optical filter for microspectrometers. The materials used for fabricating the multilayer UV filter are: silicon dioxide (SiO2), titanium dioxide (TiO2) and yttrium oxide (Y2O3). The optical filter shows a bandpass response wavelength in

  18. Ceramic fiber reinforced filter

    Science.gov (United States)

    Stinton, David P.; McLaughlin, Jerry C.; Lowden, Richard A.

    1991-01-01

    A filter for removing particulate matter from high temperature flowing fluids, and in particular gases, that is reinforced with ceramic fibers. The filter has a ceramic base fiber material in the form of a fabric, felt, paper of the like, with the refractory fibers thereof coated with a thin layer of a protective and bonding refractory applied by chemical vapor deposition techniques. This coating causes each fiber to be physically joined to adjoining fibers so as to prevent movement of the fibers during use and to increase the strength and toughness of the composite filter. Further, the coating can be selected to minimize any reactions between the constituents of the fluids and the fibers. A description is given of the formation of a composite filter using a felt preform of commercial silicon carbide fibers together with the coating of these fibers with pure silicon carbide. Filter efficiency approaching 100% has been demonstrated with these filters. The fiber base material is alternately made from aluminosilicate fibers, zirconia fibers and alumina fibers. Coating with Al.sub.2 O.sub.3 is also described. Advanced configurations for the composite filter are suggested.

  19. Survey method for radiological surveys of 300 FF-1 Operable Unit soil and materials

    International Nuclear Information System (INIS)

    Greif, A.A.

    1997-06-01

    This technical basis document is to be used to survey soils at the 300-FF-1 Operable Unit during remediation of the site. Its purpose is to provide a basis for the survey methods to be employed by the Radiological Control Technician to determine if excavated areas require continued remediation in accordance with the Record of Decision for the operable unit

  20. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: DEVILBISS JGHV-531-46FF HVLP SPRAY GUN

    Science.gov (United States)

    This report presents the results of the verification test of the DeVilbiss JGHV-531-46FF high-volume, low-pressure pressure-feed spray gun, hereafter referred to as the DeVilbiss JGHV, which is designed for use in industrial finishing. The test coating chosen by ITW Industrial Fi...

  1. USHPRR FUEL FABRICATION PILLAR: FABRICATION STATUS, PROCESS OPTIMIZATIONS, AND FUTURE PLANS

    Energy Technology Data Exchange (ETDEWEB)

    Wight, Jared M.; Joshi, Vineet V.; Lavender, Curt A.

    2018-03-12

    The Fuel Fabrication (FF) Pillar, a project within the U.S. High Performance Research Reactor Conversion program of the National Nuclear Security Administration’s Office of Material Management and Minimization, is tasked with the scale-up and commercialization of high-density monolithic U-Mo fuel for the conversion of appropriate research reactors to use of low-enriched fuel. The FF Pillar has made significant steps to demonstrate and optimize the baseline co-rolling process using commercial-scale equipment at both the Y-12 National Security Complex (Y-12) and BWX Technologies (BWXT). These demonstrations include the fabrication of the next irradiation experiment, Mini-Plate 1 (MP-1), and casting optimizations at Y-12. The FF Pillar uses a detailed process flow diagram to identify potential gaps in processing knowledge or demonstration, which helps direct the strategic research agenda of the FF Pillar. This paper describes the significant progress made toward understanding the fuel characteristics, and models developed to make informed decisions, increase process yield, and decrease lifecycle waste and costs.

  2. Automation of the CHARMM General Force Field (CGenFF) I: bond perception and atom typing.

    Science.gov (United States)

    Vanommeslaeghe, K; MacKerell, A D

    2012-12-21

    Molecular mechanics force fields are widely used in computer-aided drug design for the study of drug-like molecules alone or interacting with biological systems. In simulations involving biological macromolecules, the biological part is typically represented by a specialized biomolecular force field, while the drug is represented by a matching general (organic) force field. In order to apply these general force fields to an arbitrary drug-like molecule, functionality for assignment of atom types, parameters, and charges is required. In the present article, which is part I of a series of two, we present the algorithms for bond perception and atom typing for the CHARMM General Force Field (CGenFF). The CGenFF atom typer first associates attributes to the atoms and bonds in a molecule, such as valence, bond order, and ring membership among others. Of note are a number of features that are specifically required for CGenFF. This information is then used by the atom typing routine to assign CGenFF atom types based on a programmable decision tree. This allows for straightforward implementation of CGenFF's complicated atom typing rules and for equally straightforward updating of the atom typing scheme as the force field grows. The presented atom typer was validated by assigning correct atom types on 477 model compounds including in the training set as well as 126 test-set molecules that were constructed to specifically verify its different components. The program may be utilized via an online implementation at https://www.paramchem.org/ .

  3. IMPLEMENTATION AND COMPARISON OF DIFFERENT CIC FILTER STRUCTURE FOR DECIMATION

    Directory of Open Access Journals (Sweden)

    M. Madheswaran

    2013-06-01

    Full Text Available This paper briefs an implementation of different CIC filter architectures for decimation. The different decimation filter structures are implemented using cascaded integrator-comb filter to work for the down sampling ratio of 8. The prototype is designed with MATLAB Simulink model and it is converted to VHDL code using Xilinx system generator. Prototype is implemented in Virtex V- XC5VLX110T-3ff1136 FPGA kit and simulation results and device utilization reports are generated and tabulated. Finally different architectures are compared using number of used LUTs, Registers, Power consumption etc.

  4. Rectifier Filters

    Directory of Open Access Journals (Sweden)

    Y. A. Bladyko

    2010-01-01

    Full Text Available The paper contains definition of a smoothing factor which is suitable for any rectifier filter. The formulae of complex smoothing factors have been developed for simple and complex passive filters. The paper shows conditions for application of calculation formulae and filters

  5. Surface radiation survey and soil sampling of the 300-FF-1 operable unit, Hanford Site, southeastern Washington: A case study

    International Nuclear Information System (INIS)

    Teel, S.S.; Olsen, K.B.

    1990-10-01

    The methods used for conducting a radiological characterization of the soil surface for the Phase I Remedial Investigation of a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) site is presented via a case study. The study site is an operable unit (300-FF-1) located in and adjacent to the 300 Area of the US Department of Energy's Hanford Site in southeastern Washington State. The operable unit contains liquid and solid waste disposal facilities associated with nuclear fuels fabrication. Continuous surface radiation surveying and soil sampling of selected locations were conducted. Contamination was found in several locations within the operable unit including areas near the liquid and solid waste disposal facilities. Instruments used during surveying included portable beta/gamma (P-11) detectors, and the Ultrasonic Ranging and Data System using an NaI (Tl) detector. Laboratory analyses results indicate that above-background radiation levels were primarily due to the presence of uranium. Both types of field instruments used in the study were effective in detecting surface contamination from radionuclides; however, each had specific advantages. Guidelines are presented for the optimum use of these instruments when performing a radiological characterization of the soil surface. 4 refs., 3 figs., 3 tabs

  6. A rigid porous filter and filtration method

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Ta-Kuan; Straub, Douglas, Straub L.; Dennis, Richard A.

    1998-12-01

    The present invention involves a porous rigid filter comprising a plurality of concentric filtration elements having internal flow passages and forming external flow passages there between. The present invention also involves a pressure vessel containing the filter for the removal of particulate from high pressure particulate containing gases, and further involves a method for using the filter to remove such particulate. The present filter has the advantage of requiring fewer filter elements due to the high surface area- to-volume ratio provided by the filter, requires a reduced pressure vessel size, and exhibits enhanced mechanical design properties, improved cleaning properties, configuration options, modularity and ease of fabrication.

  7. Carbon nanotube filters

    Science.gov (United States)

    Srivastava, A.; Srivastava, O. N.; Talapatra, S.; Vajtai, R.; Ajayan, P. M.

    2004-09-01

    Over the past decade of nanotube research, a variety of organized nanotube architectures have been fabricated using chemical vapour deposition. The idea of using nanotube structures in separation technology has been proposed, but building macroscopic structures that have controlled geometric shapes, density and dimensions for specific applications still remains a challenge. Here we report the fabrication of freestanding monolithic uniform macroscopic hollow cylinders having radially aligned carbon nanotube walls, with diameters and lengths up to several centimetres. These cylindrical membranes are used as filters to demonstrate their utility in two important settings: the elimination of multiple components of heavy hydrocarbons from petroleum-a crucial step in post-distillation of crude oil-with a single-step filtering process, and the filtration of bacterial contaminants such as Escherichia coli or the nanometre-sized poliovirus (~25 nm) from water. These macro filters can be cleaned for repeated filtration through ultrasonication and autoclaving. The exceptional thermal and mechanical stability of nanotubes, and the high surface area, ease and cost-effective fabrication of the nanotube membranes may allow them to compete with ceramic- and polymer-based separation membranes used commercially.

  8. FF-LYNX: protocol and interfaces for the control and readout of future Silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Amendola, A; Bianchi, G; Fanucci, L; Saponara, S; Tongiani, C [Universita di Pisa, Dipartimento di Ingegneria dell' Informazione (DII-EIT), Via G. Caruso 16, 56122 Pisa (Italy); Castaldi, R; Minuti, M; Verdini, P G [INFN, Sezione di Pisa, Largo B. Pontecorvo 3, 56018 Pisa (Italy); Incandela, J; Magazzu, G; Rossin, R, E-mail: Guido.Magazzu@pi.infn.i [University of California at Santa Barbara (UCSB), Department of Physics, 5113 Broida Hall, CA 93106 Santa Barbara (United States)

    2010-06-15

    The FF-LYNX protocol provides an innovative solution for the integrated distribution of Timing, Trigger and Control signals and the data readout in future High Energy Physics experiments. Transmitter and receiver interfaces implementing the FF-LYNX protocol have been simulated with a high-level simulator and in an FPGA based emulator. The design of the interfaces in a commercial CMOS technology as radiation tolerant and low power modules is ongoing and the submission of a test circuit is foreseen in fall 2010. The key features of the protocol are described in this paper as well as its possible application for the transmission from Silicon Trackers to trigger processors with short and constant latency of data to be used for the L1 trigger generation.

  9. High-quality genome sequence and description of Bacillus ndiopicus strain FF3T sp. nov.

    Directory of Open Access Journals (Sweden)

    C.I. Lo

    2015-11-01

    Full Text Available Strain FF3T was isolated from the skin-flora of a 39-year-old healthy Senegalese man. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry did not allow any identification. This strain exhibited a 16S rRNA sequence similarity of 96.8% with Bacillus massiliensis, the phylogenetically closest species with standing nomenclature. Using a polyphasic study made of phenotypic and genomic analyses, strain FF3T was Gram-positive, aeroanaerobic and rod shaped and exhibited a genome of 4 068 720 bp with a G+C content of 37.03% that coded 3982 protein-coding and 67 RNA genes (including four rRNA operons. On the basis of these data, we propose the creation of Bacillus ndiopicus sp. nov.

  10. Biota of the 300-FF-1 operable unit. [Westinghouse Hanford Company

    Energy Technology Data Exchange (ETDEWEB)

    Rickard, W.H. Jr.; Fitzner, R.E.; Brandt, C.A.

    1990-10-01

    This report summarizes Task 5a-2 of the Phase I Remedial Investigation -- Operable Unit Characterization of the 300-FF-1 Operable Unit on the Hanford Site, near Richland, Washington. The ultimate goal of Phase I is to determine the nature and extent of the threat to public health and the environment from releases of hazardous substances from the operable unit. The purpose of Task 5a-2 was to determine what species inhabit the 300-FF-1 Operable Unit and how they use the unit. The focus is on those species listed as endangered or threatened, those that are economically important, or those that constitute significant components of the human food chain. 39 refs., 5 figs., 5 tabs.

  11. FF-i alafestivalid lükati käima

    Index Scriptorium Estoniae

    2010-01-01

    14. korda toimuva Pimedate Ööde Filmifestivali tänavune fookus on soome filmidel ja Euroopa filmiauhindade nominentide töödel. PÖFF-i põhiprogrammi tutvustab peakorraldaja Tiina Lokk, tudengi- ja lühifilmide festivali Sleepwalkers kava festivali juht Helen Vinogradov, animafilmide festivali Animated Dreams kava programmijuht Heilika Pikkov, laste- ja noortefilmide festivali Just Film kava festivali juht Mikk Granström

  12. AdaFF: Adaptive Failure-Handling Framework for Composite Web Services

    Science.gov (United States)

    Kim, Yuna; Lee, Wan Yeon; Kim, Kyong Hoon; Kim, Jong

    In this paper, we propose a novel Web service composition framework which dynamically accommodates various failure recovery requirements. In the proposed framework called Adaptive Failure-handling Framework (AdaFF), failure-handling submodules are prepared during the design of a composite service, and some of them are systematically selected and automatically combined with the composite Web service at service instantiation in accordance with the requirement of individual users. In contrast, existing frameworks cannot adapt the failure-handling behaviors to user's requirements. AdaFF rapidly delivers a composite service supporting the requirement-matched failure handling without manual development, and contributes to a flexible composite Web service design in that service architects never care about failure handling or variable requirements of users. For proof of concept, we implement a prototype system of the AdaFF, which automatically generates a composite service instance with Web Services Business Process Execution Language (WS-BPEL) according to the users' requirement specified in XML format and executes the generated instance on the ActiveBPEL engine.

  13. Superstring Z' bozon in e-e+ → ff-bar annihilation

    International Nuclear Information System (INIS)

    Abdullaev, S.K.; Mukhtarov, A.I.

    1989-01-01

    An influence of an additional neutral Z' bozon on characteristics of e - e + →ff-bar processes is studied, where ff-bar is a pair of arbitrary particles (leptons, nucleons, hyperons, pseudoscalar or vector mesons etc.). The general expression for the differential cross sections of e - e + →ff-bar processes is obtained with arbitrary polarizations of an electron-positron pair by introducing of structure functions, and the following integral characteristics are considered: polarized forward A F (λ 2 ) and backward A B (λ 2 ) assymmetries; right-left asymmetry A RL ; forward-backward asymmetry in the case of longitudinal polarized e - e + pair annihilation A BH (λ 2 ); transversal spin assymmetries A Φ (1) and A Φ (2) ; the degree of longitudinal polarization of r lepton P in e - e + → r - r + r - r + process. The general expressions for these characteristics are found and their quantitative estimates are given in the framework of superstring E 6 -model. 20 refs.; 5 figs.; 2 tabs

  14. Enhanced Particle Swarm Optimization Algorithm: Efficient Training of ReaxFF Reactive Force Fields.

    Science.gov (United States)

    Furman, David; Carmeli, Benny; Zeiri, Yehuda; Kosloff, Ronnie

    2018-05-04

    Particle swarm optimization is a powerful metaheuristic population-based global optimization algorithm. However, when applied to non-separable objective functions its performance on multimodal landscapes is significantly degraded. Here we show that a significant improvement in the search quality and efficiency on multimodal functions can be achieved by enhancing the basic rotation-invariant particle swarm optimization algorithm with isotropic Gaussian mutation operators. The new algorithm demonstrates a superior performance across several nonlinear, multimodal benchmark functions compared to the rotation-invariant Particle Swam Optimization (PSO) algorithm and the well-established simulated annealing and sequential one-parameter parabolic interpolation methods. A search for the optimal set of parameters for the dispersion interaction model in ReaxFF-lg reactive force field is carried out with respect to accurate DFT-TS calculations. The resulting optimized force field accurately describes the equations of state of several high-energy molecular crystals where such interactions are of crucial importance. The improved algorithm also presents a better performance compared to a Genetic Algorithm optimization method in the optimization of a ReaxFF-lg correction model parameters. The computational framework is implemented in a standalone C++ code that allows a straightforward development of ReaxFF reactive force fields.

  15. Filter apparatus

    International Nuclear Information System (INIS)

    Butterworth, D.J.

    1980-01-01

    This invention relates to liquid filters, precoated by replaceable powders, which are used in the production of ultra pure water required for steam generation of electricity. The filter elements are capable of being installed and removed by remote control so that they can be used in nuclear power reactors. (UK)

  16. Poster - 56: Preliminary comparison of FF- and FFF-VMAT for prostate plans with higher rectal dose

    International Nuclear Information System (INIS)

    Liu, Baochang; Darko, Johnson; Osei, Ernest

    2016-01-01

    Purpose: A recent retrospective study found 53 patients previously treated to 78Gy/39 using flattened filtered (FF) 6X-VMAT at GRRCC had rectal DVH more than one standard deviation higher than the average. This study was to investigate if using 6FFFor10FFF beams could reduce these DVHs without compromising target coverage. Methods: Twenty patients’ plans were re-planed with 2-arc 6X-VMAT, 6FFF-VMAT and 10FFF-VMAT using the Eclipse TPS following departmental protocol. All plans had the same optimization and normalization, and were evaluated against the acceptance criteria from the QUANTEC and Emami. Statistical differences in the mean dose to OARs (D m ) and PTV homogeneity index (HI) between energies were tested using the paired sample Wilcoxon signed rank statistical method (p<0.05). Beam delivery accuracy was checked on five patients using portal dosimetry (PD). Results: The PTV HI for the 10FFF shows no statistical difference from the 6X. All the OARs, except left femoral head with 6FFF, have significantly lower Dm using 6FFF and 10FFF .There is no difference in the maximum doses to rectum and bladder and are limited by the prescribed doses. Measurements show good agreements in the gamma evaluation (3%/3mm) for all energies. Conclusion: This preliminary study shows that doses to the OARs are reduced using 10FFF for the same target coverage. The plans using 6FFF result in lower doses to some OARs, and statistically different PTV HI. All plans showed very good agreement with measurements.

  17. Poster - 56: Preliminary comparison of FF- and FFF-VMAT for prostate plans with higher rectal dose

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Baochang; Darko, Johnson; Osei, Ernest [Grand River Regional Cancer Centre, Kitchener, Ontario (Canada)

    2016-08-15

    Purpose: A recent retrospective study found 53 patients previously treated to 78Gy/39 using flattened filtered (FF) 6X-VMAT at GRRCC had rectal DVH more than one standard deviation higher than the average. This study was to investigate if using 6FFFor10FFF beams could reduce these DVHs without compromising target coverage. Methods: Twenty patients’ plans were re-planed with 2-arc 6X-VMAT, 6FFF-VMAT and 10FFF-VMAT using the Eclipse TPS following departmental protocol. All plans had the same optimization and normalization, and were evaluated against the acceptance criteria from the QUANTEC and Emami. Statistical differences in the mean dose to OARs (D{sub m}) and PTV homogeneity index (HI) between energies were tested using the paired sample Wilcoxon signed rank statistical method (p<0.05). Beam delivery accuracy was checked on five patients using portal dosimetry (PD). Results: The PTV HI for the 10FFF shows no statistical difference from the 6X. All the OARs, except left femoral head with 6FFF, have significantly lower Dm using 6FFF and 10FFF .There is no difference in the maximum doses to rectum and bladder and are limited by the prescribed doses. Measurements show good agreements in the gamma evaluation (3%/3mm) for all energies. Conclusion: This preliminary study shows that doses to the OARs are reduced using 10FFF for the same target coverage. The plans using 6FFF result in lower doses to some OARs, and statistically different PTV HI. All plans showed very good agreement with measurements.

  18. Definition of parameters for quality assurance of flattening filter free (FFF) photon beams in radiation therapy

    International Nuclear Information System (INIS)

    Fogliata, A.; Garcia, R.; Knöös, T.; Nicolini, G.; Clivio, A.; Vanetti, E.; Khamphan, C.; Cozzi, L.

    2012-01-01

    Purpose: Flattening filter free (FFF) beams generated by medical linear accelerators have recently started to be used in radiotherapy clinical practice. Such beams present fundamental differences with respect to the standard filter flattened (FF) beams, making the generally used dosimetric parameters and definitions not always viable. The present study will propose possible definitions and suggestions for some dosimetric parameters for use in quality assurance of FFF beams generated by medical linacs in radiotherapy. Methods: The main characteristics of the photon beams have been analyzed using specific data generated by a Varian TrueBeam linac having both FFF and FF beams of 6 and 10 MV energy, respectively. Results: Definitions for dose profile parameters are suggested starting from the renormalization of the FFF with respect to the corresponding FF beam. From this point the flatness concept has been translated into one of “unflatness” and other definitions have been proposed, maintaining a strict parallelism between FFF and FF parameter concepts. Conclusions: Ideas for quality controls used in establishing a quality assurance program when introducing FFF beams into the clinical environment are given here, keeping them similar to those used for standard FF beams. By following the suggestions in this report, the authors foresee that the introduction of FFF beams into a clinical radiotherapy environment will be as safe and well controlled as standard beam modalities using the existing guidelines.

  19. Spatial filtering with photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Maigyte, Lina [Departament de Física i Enginyeria Nuclear, Universitat Politècnica de Catalunya, Rambla Sant Nebridi 22, Terrassa 08222 (Spain); Staliunas, Kestutis [Departament de Física i Enginyeria Nuclear, Universitat Politècnica de Catalunya, Rambla Sant Nebridi 22, Terrassa 08222 (Spain); Institució Catalana de Recerca i Estudis Avançats (ICREA), Pg. Lluís Companys 23, Barcelona 08010 (Spain)

    2015-03-15

    Photonic crystals are well known for their celebrated photonic band-gaps—the forbidden frequency ranges, for which the light waves cannot propagate through the structure. The frequency (or chromatic) band-gaps of photonic crystals can be utilized for frequency filtering. In analogy to the chromatic band-gaps and the frequency filtering, the angular band-gaps and the angular (spatial) filtering are also possible in photonic crystals. In this article, we review the recent advances of the spatial filtering using the photonic crystals in different propagation regimes and for different geometries. We review the most evident configuration of filtering in Bragg regime (with the back-reflection—i.e., in the configuration with band-gaps) as well as in Laue regime (with forward deflection—i.e., in the configuration without band-gaps). We explore the spatial filtering in crystals with different symmetries, including axisymmetric crystals; we discuss the role of chirping, i.e., the dependence of the longitudinal period along the structure. We also review the experimental techniques to fabricate the photonic crystals and numerical techniques to explore the spatial filtering. Finally, we discuss several implementations of such filters for intracavity spatial filtering.

  20. Structural Shielding Design of a 6 MV Flattening Filter Free Linear Accelerator: Indian Scenario

    OpenAIRE

    Mishra, Bibekananda; Selvam, T. Palani; Sharma, P. K. Dash

    2017-01-01

    Detailed structural shielding of primary and secondary barriers for a 6 MV medical linear accelerator (LINAC) operated with flattening filter (FF) and flattening filter free (FFF) modes are calculated. The calculations have been carried out by two methods, one using the approach given in National Council on Radiation Protection (NCRP) Report No. 151 and the other based on the monitor units (MUs) delivered in clinical practice. Radiation survey of the installations was also carried out. NCRP a...

  1. Adaptation of a RAS pathway activation signature from FF to FFPE tissues in colorectal cancer

    Directory of Open Access Journals (Sweden)

    Bernard Omolo

    2016-10-01

    Full Text Available Abstract Background The KRAS gene is mutated in about 40 % of colorectal cancer (CRC cases, which has been clinically validated as a predictive mutational marker of intrinsic resistance to anti-EGFR inhibitor (EGFRi therapy. Since nearly 60 % of patients with a wild type KRAS fail to respond to EGFRi combination therapies, there is a need to develop more reliable molecular signatures to better predict response. Here we address the challenge of adapting a gene expression signature predictive of RAS pathway activation, created using fresh frozen (FF tissues, for use with more widely available formalin fixed paraffin-embedded (FFPE tissues. Methods In this study, we evaluated the translation of an 18-gene RAS pathway signature score from FF to FFPE in 54 CRC cases, using a head-to-head comparison of five technology platforms. FFPE-based technologies included the Affymetrix GeneChip (Affy, NanoString nCounter™ (NanoS, Illumina whole genome RNASeq (RNA-Acc, Illumina targeted RNASeq (t-RNA, and Illumina stranded Total RNA-rRNA-depletion (rRNA. Results Using Affy_FF as the “gold” standard, initial analysis of the 18-gene RAS scores on all 54 samples shows varying pairwise Spearman correlations, with (1 Affy_FFPE (r = 0.233, p = 0.090; (2 NanoS_FFPE (r = 0.608, p < 0.0001; (3 RNA-Acc_FFPE (r = 0.175, p = 0.21; (4 t-RNA_FFPE (r = −0.237, p = 0.085; (5 and t-RNA (r = −0.012, p = 0.93. These results suggest that only NanoString has successful FF to FFPE translation. The subsequent removal of identified “problematic” samples (n = 15 and genes (n = 2 further improves the correlations of Affy_FF with three of the five technologies: Affy_FFPE (r = 0.672, p < 0.0001; NanoS_FFPE (r = 0.738, p < 0.0001; and RNA-Acc_FFPE (r = 0.483, p = 0.002. Conclusions Of the five technology platforms tested, NanoString technology provides a more faithful translation of the RAS pathway gene

  2. Phase 1 and 2 feasibility study report for the 300-FF-1 Operable Unit

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    The 300-FF-1 Operable Unit (OU) feasibility study (FS) presented in this document completes the FS process only through the first two study phases: Phase I, Remedial Alternatives Development, and Phase II, Remedial Alternatives Screening in accordance with CERCIA guidance for performing Remedial Investigations and Feasibility Studies (RI/FS) (EPA 1988a). This Phase I/II study provides a generalized view of workable remedial technologies as applied to the site contamination problems as a whole. Phase III, Detailed Analysis of Alternatives, will be performed at a later date to further evaluate screened alternatives based on the nine criteria in the CERCLA RI/FS guidance. The purpose of this Phase I/II FS is to develop and screen a range of alternatives for remediation of contamination present in the vadose zone of the 300-FF-1 OU. The scope of work for this Phase I/II FS includes five primary tasks: 1. Review existing documents and their associated data from relevant investigations and studies; 2. Establish remedial action objectives (RAO) and general response actions (GRA); 3. Identify applicable or relevant and appropriate requirements (ARARS) pertinent to all general response actions (including waste disposal); 4. Develop remedial alternatives (Phase I) applicable to the 300-FF-1 OU including identification and screening of technologies and process options, and assembly of remedial alternatives from representative technology types; 5. Screen alternatives (Phase II) developed in Phase I for implementability, effectiveness, and cost to identify those alternatives which warrant advancement to the detailed analysis phase (Phase III) of the FS.

  3. Filter systems

    International Nuclear Information System (INIS)

    Vanin, V.R.

    1990-01-01

    The multidetector systems for high resolution gamma spectroscopy are presented. The observable parameters for identifying nuclides produced simultaneously in the reaction are analysed discussing the efficiency of filter systems. (M.C.K.)

  4. New polymorphous computing fabric

    International Nuclear Information System (INIS)

    Wolinski, Christophe; Gokhale, Maya; McCabe, Kevin P.

    2002-01-01

    This paper introduces a new polymorphous computing Fabric well suited to DSP and Image Processing and describes its implementation on a Configurable System on a Chip (CSOC). The architecture is highly parameterized and enables customization of the synthesized Fabric to achieve high performance for a specific class of application. For this reason it can be considered to be a generic model for hardware accelerator synthesis from a high level specification. Another important innovation is the Fabric uses a global memory concept, which gives the host processor random access to all the variables and instructions on the Fabric. The Fabric supports different computing models including MIMD, SPMD and systolic flow and permits dynamic reconfiguration. We present a specific implementation of a bank of FIR filters on a Fabric composed of 52 cells on the Altera Excalibur ARM running at 33 MHz. The theoretical performance of this Fabric is 1.8 GMACh. For the FIR application we obtain 1.6 GMAC/s real performance. Some automatic tools have been developed like the tool to provide a host access utility and assembler.

  5. ReaxFF Reactive Force-Field Study of Molybdenum Disulfide (MoS2).

    Science.gov (United States)

    Ostadhossein, Alireza; Rahnamoun, Ali; Wang, Yuanxi; Zhao, Peng; Zhang, Sulin; Crespi, Vincent H; van Duin, Adri C T

    2017-02-02

    Two-dimensional layers of molybdenum disulfide, MoS 2 , have been recognized as promising materials for nanoelectronics due to their exceptional electronic and optical properties. Here we develop a new ReaxFF reactive potential that can accurately describe the thermodynamic and structural properties of MoS 2 sheets, guided by extensive density functional theory simulations. This potential is then applied to the formation energies of five different types of vacancies, various vacancy migration barriers, and the transition barrier between the semiconducting 2H and metallic 1T phases. The energetics of ripplocations, a recently observed defect in van der Waals layers, is examined, and the interplay between these defects and sulfur vacancies is studied. As strain engineering of MoS 2 sheets is an effective way to manipulate the sheets' electronic and optical properties, the new ReaxFF description can provide valuable insights into morphological changes that occur under various loading conditions and defect distributions, thus allowing one to tailor the electronic properties of these 2D crystals.

  6. Phase I and II feasibility study report for the 300-FF-5 operable unit

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    The purpose of this Phase I/II feasibility study is to assemble and screen a list of alternatives for remediation of the 300-FF-5 operable site on the Hanford Reservation. This screening is based on information gathered in the Phase I Remedial Investigation (RI) and on currently available information on remediation technologies. The alternatives remaining after screening provide a range of response actions for remediation. In addition, key data needs are identified for collection during a Phase II RI (if necessary). This Phase I/II FS represents a primary document as defined by the Tri-Party Agreement, but will be followed by a Phase III FS that will further develop the alternatives and provide a detailed evaluation of them. The following remedial action objectives were identified for the 300-FF-5 operable unit: Limit current human exposure to contaminated groundwater in the unit; Limit discharge of contaminated groundwater to the Columbia River; Reduce contaminant concentrations in groundwater below acceptable levels by the year 2018.

  7. Report on geological surveys in the 300-FF-1 operable unit

    International Nuclear Information System (INIS)

    Sandness, G.A.

    1991-03-01

    This report describes a set of geophysical surveys performed by the Pacific Northwest Laboratory at selected locations within the 300-FF-1 Operable Unit at Hanford. Field work and preliminary data processing activities were initiated in September 1989. These actions were terminated by the Westinghouse Hanford Company before completion in December 1989. Work was reinitiated in October 1990, to complete the processing of the data that had already been collected and to report the results. Because the field work was only partially completed, the task objectives, as presented in the Statement of Work, could not be fully met. This report is, therefore, a progress report covering the work performed through December 11, 1989. This task involved (1) ground-penetrating radar surveys of the 618-4 and 618-5 Burial Grounds, and (2) ground-penetrating radar and electromagnetic induction surveys along the assumed routes of the abandoned process sewers and radioactive liquid waste sewers in the 300-FF-1 Operable Unit. The surveys in the burial grounds were intended to identify burial trenches and pits, to determine the depth of fill, and to locate waste materials, including any that might be outside the perimeter fences. The surveys along the sewer routes were intended, first, to confirm the locations of the sewers as shown on existing maps or to otherwise accurately determine their locations, and second, to attempt to identify locations of possible leaks. 3 refs., 3 figs., 2 tabs

  8. Phase I and II feasibility study report for the 300-FF-5 operable unit

    International Nuclear Information System (INIS)

    1993-01-01

    The purpose of this Phase I/II feasibility study is to assemble and screen a list of alternatives for remediation of the 300-FF-5 operable site on the Hanford Reservation. This screening is based on information gathered in the Phase I Remedial Investigation (RI) and on currently available information on remediation technologies. The alternatives remaining after screening provide a range of response actions for remediation. In addition, key data needs are identified for collection during a Phase II RI (if necessary). This Phase I/II FS represents a primary document as defined by the Tri-Party Agreement, but will be followed by a Phase III FS that will further develop the alternatives and provide a detailed evaluation of them. The following remedial action objectives were identified for the 300-FF-5 operable unit: Limit current human exposure to contaminated groundwater in the unit; Limit discharge of contaminated groundwater to the Columbia River; Reduce contaminant concentrations in groundwater below acceptable levels by the year 2018

  9. Fabrication Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — The Fabrication Facilities are a direct result of years of testing support. Through years of experience, the three fabrication facilities (Fort Hood, Fort Lewis, and...

  10. High temperature superconducting YBCO microwave filters

    Science.gov (United States)

    Aghabagheri, S.; Rasti, M.; Mohammadizadeh, M. R.; Kameli, P.; Salamati, H.; Mohammadpour-Aghdam, K.; Faraji-Dana, R.

    2018-06-01

    Epitaxial thin films of YBCO high temperature superconductor are widely used in telecommunication technology such as microwave filter, antenna, coupler and etc., due to their lower surface resistance and lower microwave loss than their normal conductor counterparts. Thin films of YBCO were fabricated by PLD technique on LAO substrate. Transition temperature and width were 88 K and 3 K, respectively. A filter pattern was designed and implemented by wet photolithography method on the films. Characterization of the filter at 77 K has been compared with the simulation results and the results for a made gold filter. Both YBCO and gold filters show high microwave loss. For YBCO filter, the reason may be due to the improper contacts on the feedlines and for gold filter, low thickness of the gold film has caused the loss increased.

  11. Mode-routed fiber-optic add-drop filter

    Science.gov (United States)

    Moslehi, Behzad (Inventor); Black, Richard James (Inventor); Shaw, Herbert John (Inventor)

    2000-01-01

    New elements mode-converting two-mode grating and mode-filtering two-mode coupler are disclosed and used as elements in a system for communications, add-drop filtering, and strain sensing. Methods of fabrication for these new two-mode gratings and mode-filtering two-mode couplers are also disclosed.

  12. Generalised Filtering

    Directory of Open Access Journals (Sweden)

    Karl Friston

    2010-01-01

    Full Text Available We describe a Bayesian filtering scheme for nonlinear state-space models in continuous time. This scheme is called Generalised Filtering and furnishes posterior (conditional densities on hidden states and unknown parameters generating observed data. Crucially, the scheme operates online, assimilating data to optimize the conditional density on time-varying states and time-invariant parameters. In contrast to Kalman and Particle smoothing, Generalised Filtering does not require a backwards pass. In contrast to variational schemes, it does not assume conditional independence between the states and parameters. Generalised Filtering optimises the conditional density with respect to a free-energy bound on the model's log-evidence. This optimisation uses the generalised motion of hidden states and parameters, under the prior assumption that the motion of the parameters is small. We describe the scheme, present comparative evaluations with a fixed-form variational version, and conclude with an illustrative application to a nonlinear state-space model of brain imaging time-series.

  13. Filter This

    Directory of Open Access Journals (Sweden)

    Audrey Barbakoff

    2011-03-01

    Full Text Available In the Library with the Lead Pipe welcomes Audrey Barbakoff, a librarian at the Milwaukee Public Library, and Ahniwa Ferrari, Virtual Experience Manager at the Pierce County Library System in Washington, for a point-counterpoint piece on filtering in libraries. The opinions expressed here are those of the authors, and are not endorsed by their employers. [...

  14. JC2Sat-FF : An International Collaboration Nano-Sat Project Overview of the System Analyses and Design

    Science.gov (United States)

    Yoshihara, K.; van Mierlo, M.; Ng, A.; Shankar Kumar, B.; De Ruiter, A.; Komatsu, Y.; Horiguchi, H.; Hashimoto, H.

    2008-08-01

    This paper introduces the Japan Canada Joint Collaboration Satellites - Formation Flying (JC2Sat-FF) project. JC2Sat-FF is a joint project between the Canadian Space Agency (CSA) and the Japan Aerospace Exploration Agency (JAXA) with the end goal of building, launching and operating two 20kg- class nanosatellites for technical demonstration of formation flight (FF) using differential drag technique, relative navigation using commercial off-the-shelf (COTS) dual band GPS receivers and far infra-red radiance measurement. A unique aspect of this project is that the two JC2Sats are developed by a united small team consisting of engineers and researchers from both agencies. Technical exchange in this international team gives stimulation to the members and generates a synergistic effect for the project.

  15. 300-FF-1 operable unit remedial investigation phase II report: Physical separation of soils treatability study

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-01

    This report describes the approach and results of physical separations treatability tests conducted at the Hanford Site in the North Process Pond of the 300-FF-1 Operable Unit. Physical separation of soils was identified as a remediation alternative due to the potential to significantly reduce the amount of contaminated soils prior to disposal. Tests were conducted using a system developed at Hanford consisting of modified EPA equipment integrated with screens, hoppers, conveyors, tanks, and pumps from the Hanford Site. The treatability tests discussed in this report consisted of four parts, in which an estimated 84 tons of soil was processed: (1) a pre-test run to set up the system and adjust system parameters for soils to be processed; (2) a baseline run to establish the performance of the system - Test No. 1; (3) a final run in which the system was modified as a result of findings from the baseline run - Test No. 2; and (4) water treatment.

  16. 300-FF-1 operable unit remedial investigation phase II report: Physical separation of soils treatability study

    International Nuclear Information System (INIS)

    1994-04-01

    This report describes the approach and results of physical separations treatability tests conducted at the Hanford Site in the North Process Pond of the 300-FF-1 Operable Unit. Physical separation of soils was identified as a remediation alternative due to the potential to significantly reduce the amount of contaminated soils prior to disposal. Tests were conducted using a system developed at Hanford consisting of modified EPA equipment integrated with screens, hoppers, conveyors, tanks, and pumps from the Hanford Site. The treatability tests discussed in this report consisted of four parts, in which an estimated 84 tons of soil was processed: (1) a pre-test run to set up the system and adjust system parameters for soils to be processed; (2) a baseline run to establish the performance of the system - Test No. 1; (3) a final run in which the system was modified as a result of findings from the baseline run - Test No. 2; and (4) water treatment

  17. Magnetism of FF6.2/SiO2 nanocomposites as observed by static and dynamic probes

    International Nuclear Information System (INIS)

    Vejpravova, J.; Kornak, R.; Niznansky, D.; Haimann, K.; Maruszewski, K.

    2007-01-01

    We report on magnetic behavior of the electromagnetic compatibility (EMC) compound FF6.2 and composites prepared by the modified Stoeber method using FF6.2 as the magnetic ion-containing (Fe 2+ /Fe 3+ ) precursor. The composites were characterized by the X-ray diffraction analysis (XRD) and morphology of the magnetic powders was investigated by a scanning electron microscope (SEM) and a high resolution transmision electron microscope (HR TEM). Magnetic properties of the materials were studied by measurements of the magnetization, AC susceptibility and Moessbauer spectra

  18. Can volumetric modulated arc therapy with flattening filter free beams play a role in stereotactic body radiotherapy for liver lesions? A volume-based analysis

    International Nuclear Information System (INIS)

    Reggiori, Giacomo; Mancosu, Pietro; Castiglioni, Simona; Alongi, Filippo; Pellegrini, Chiara; Lobefalo, Francesca; Catalano, Maddalena; Fogliata, Antonella; Arcangeli, Stefano; Navarria, Piera; Cozzi, Luca; Scorsetti, Marta

    2012-01-01

    Purpose: To compare volumetric modulated arc therapy with flattening filter free (FFF) and flattening filter (FF) beams in patients with hepatic metastases subject to hypofractionated radiotherapy (RT). Methods: A planning study on 13 virtual lesions of increasing volume was performed. Two single arc plans were optimized with the RapidArc technique using either FFF or FF beams. A second planning study was performed on ten patients treated for liver metastases to validate conclusions. In all cases, a dose of 75 Gy in 3 fractions was prescribed to the planning target volume (PTV) and plans were evaluated in terms of coverage, homogeneity, conformity, mean dose to healthy liver and to healthy tissue. For each parameter, results were expressed in relative terms as the percentage ratio between FFF and FF data. Results: In terms of PTV coverage, conformity index favored FFF for targets of intermediate size while FF resulted more suitable for small ( 3 ) and large (>300 cm 3 ) targets. Plans optimized with FFF beams resulted in increased sparing of healthy tissue in ≅85% of cases. Despite the qualitative results, no statistically significant differences were found between FFF and FF results. Plans optimized with un-flattened beams resulted in higher average MU/Gy than plans with FF beams. A remarkable and significant difference was observed in the beam-on time (BOT) needed to deliver plans. The BOT for FF plans was 8.2 ± 1.0 min; for FFF plans BOT was 2.2 ± 0.2 min. Conclusions: RapidArc plans optimized using FFF were dosimetrically equivalent to those optimized using FF beams, showing the feasibility of SBRT treatments with FFF beams. Some improvement in healthy tissue sparing was observed when using the FFF modality due to the different beam's profile. The main advantage was a considerable reduction of beam-on time, relevant for SBRT techniques.

  19. Factors Influencing HEPA Filter Performance

    International Nuclear Information System (INIS)

    Parsons, M.S.; Waggoner, Ch.A.

    2009-01-01

    Properly functioning HEPA air filtration systems depend on a variety of factors that start with the use of fully characterized challenge conditions for system design and then process control during operation. This paper addresses factors that should be considered during the design phase as well as operating parameters that can be monitored to ensure filter function and lifetime. HEPA filters used in nuclear applications are expected to meet design, fabrication, and performance requirements set forth in the ASME AG-1 standard. The DOE publication Nuclear Air Cleaning Handbook (NACH) is an additional guidance document for design and operation HEPA filter systems in DOE facilities. These two guidelines establish basic maximum operating parameters for temperature, maximum aerosol particle size, maximum particulate matter mass concentration, acceptable differential pressure range, and filter media velocity. Each of these parameters is discussed along with data linking variability of each parameter with filter function and lifetime. Temporal uncertainty associated with gas composition, temperature, and absolute pressure of the air flow can have a direct impact on the volumetric flow rate of the system with a corresponding impact on filter media velocity. Correlations between standard units of flow rate (standard meters per minute or cubic feet per minute) versus actual units of volumetric flow rate are shown for variations in relative humidity for a 70 deg. C to 200 deg. C temperature range as an example of gas composition that, uncorrected, will influence media velocity. The AG-1 standard establishes a 2.5 cm/s (5 feet per minute) ceiling for media velocities of nuclear grade HEPA filters. Data are presented that show the impact of media velocities from 2.0 to 4.0 cm/s media velocities (4 to 8 fpm) on differential pressure, filter efficiency, and filter lifetime. Data will also be presented correlating media velocity effects with two different particle size

  20. Fundamental study on recovery uranium oxide from HEPA filters

    International Nuclear Information System (INIS)

    Izumida, T.; Noguchi, Y.

    1993-01-01

    Large numbers of spent HEPA filters are produced at uranium fuel fabrication facilities. Uranium oxide particles have been collected on these filters. Then, a spent HEPA filter treatment system was developed from the viewpoint of recovering the UO 2 and minimizing the volume. The system consists of a mechanical separation process and a chemical dissolution process. This paper describes the results of fundamental experiments on recovering UO 2 from HEPA filters

  1. Water level measurements for modeling hydraulic properties in the 300-FF-5 and 100 Aggregate Area Operable units

    International Nuclear Information System (INIS)

    Campbell, M.D.; McMahon, W.J.; Simpson, K.R.

    1993-04-01

    Pressure transducers connected to dataloggers were used to measure ground water and Columbia River water elevations simultaneously and hourly at 35 locations in the 300-FF-5 Operable Unit and 16 locations in the 100 Aggregate Area Operable Unit on the Hanford Site. Water temperatures were also measured at 12 of these locations. This report details the findings of these studies

  2. Soovitus: täna PÖFF-il / Erik Aru, Dannar Leitmaa, Tanel Veenre, Mart Niineste, Kaarel Kressa

    Index Scriptorium Estoniae

    Aru, Erik

    2009-01-01

    ff-i mängufilmidest - "Emma Blanki viimased päevad" (rež. Alex Van Warmerdam ; Holland), "Laul Tšingis-khaani kahest hobusest" (rež. Byambasuren Davaa; Saksamaa), "Calamari Union (Remake)" (rež. Richard Lefebvre ; USA), "Raev" (rež. Sally Potter ; Suurbritannia - USA), "Contact High" (rež. Michael Glawogger ; Austria - Saksamaa - Poola - Bulgaaria)

  3. Spatial filters on demand based on aperiodic Photonic Crystals

    Energy Technology Data Exchange (ETDEWEB)

    Gailevicius, Darius; Purlys, Vytautas; Peckus, Martynas; Gadonas, Roaldas [Laser Research Center, Department of Quantum Electronics, Vilnius University (Lithuania); Staliunas, Kestutis [DONLL, Departament de Fisica, Universitat Politecnica de Catalunya (UPC), Terrassa (Spain); Institucio Catalana de Recerca i Estudis Avancats (ICREA), Barcelona (Spain)

    2017-08-15

    Photonic Crystal spatial filters, apart from stand-alone spatial filtering function, can also suppress multi-transverse-mode operation in laser resonators. Here it is shown that such photonic crystals can be designed by solving the inverse problem: for a given spatial filtering profile. Optimized Photonic Crystal filters were fabricated in photosensitive glass. Experiments have shown that such filters provide a more pronounced filtering effect for total and partial transmissivity conditions. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. Bag filters

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, M; Komeda, I; Takizaki, K

    1982-01-01

    Bag filters are widely used throughout the cement industry for recovering raw materials and products and for improving the environment. Their general mechanism, performance and advantages are shown in a classification table, and there are comparisons and explanations. The outer and inner sectional construction of the Shinto ultra-jet collector for pulverized coal is illustrated and there are detailed descriptions of dust cloud prevention, of measures used against possible sources of ignition, of oxygen supply and of other topics. Finally, explanations are given of matters that require careful and comprehensive study when selecting equipment.

  5. Digital filters

    CERN Document Server

    Hamming, Richard W

    1997-01-01

    Digital signals occur in an increasing number of applications: in telephone communications; in radio, television, and stereo sound systems; and in spacecraft transmissions, to name just a few. This introductory text examines digital filtering, the processes of smoothing, predicting, differentiating, integrating, and separating signals, as well as the removal of noise from a signal. The processes bear particular relevance to computer applications, one of the focuses of this book.Readers will find Hamming's analysis accessible and engaging, in recognition of the fact that many people with the s

  6. Development and testing the modular fireproof fine filters on the basis of glass paper

    International Nuclear Information System (INIS)

    Rovnyj, S.I.; Glagolenko, Yu.V.; Pyatin, N.P.; Tranchuk, O.A.; Maksimov, V.E.; Afanas'eva, E.V.

    2006-01-01

    Paper describes a procedure to fabricate modified module glass paper fine filters to trap radioactive substances (14 models). The mentioned filters are made of a glass paper ensuring their fire-resistance. Paper describes the procedure of service life tests of the designed filters and the efficient procedure to extract valuable components from the spent filters [ru

  7. Technical Note: On the impact of the incident electron beam energy on the primary dose component of flattening filter free photon beams.

    Science.gov (United States)

    Kuess, Peter; Georg, Dietmar; Palmans, Hugo; Lechner, Wolfgang

    2016-08-01

    For commercially available linear accelerators (Linacs), the electron energies of flattening filter free (FFF) and flattened (FF) beams are either identical or the electron energy of the FFF beam is increased to match the percentage depth dose curve (PDD) of the FF beam (in reference geometry). This study focuses on the primary dose components of FFF beams for both kinds of settings, studied on the same Linac. The measurements were conducted on a VersaHD Linac (Elekta, Crawley, UK) for both FF and FFF beams with nominal energies of 6 and 10 MV. In the clinical setting of the VersaHD, the energy of FFFM (Matched) beams is set to match the PDDs of the FF beams. In contrast the incident electron beam of the FFFU beam was set to the same energy as for the FF beam. Half value layers (HVLs) and a dual parameter beam quality specifier (DPBQS) were determined. For the 6 MV FFFM beam, HVL and DPBQS values were very similar compared to those of the 6 MV FF beam, while for the 10 MV FFFM and FF beams, only %dd(10)x and HVL values were comparable (differences below 1.5%). This shows that matching the PDD at one depth does not guarantee other beam quality dependent parameters to be matched. For FFFU beams, all investigated beam quality specifiers were significantly different compared to those for FF beams of the same nominal accelerator potential. The DPBQS of the 6 MV FF and FFFM beams was equal within the measurement uncertainty and was comparable to published data of a machine with similar TPR20,10 and %dd(10)x. In contrast to that, the DPBQS's two parameters of the 10 MV FFFM beam were substantially higher compared to those for the 10 MV FF beam. PDD-matched FF and FFF beams of both nominal accelerator potentials were observed to have similar HVL values, indicating similarity of their primary dose components. Using the DPBQS revealed that the mean attenuation coefficient was found to be the same within the uncertainty of 0.8% for 6 MV FF and 6 MV FFFM beams, while for 10 MV

  8. Technical Note: On the impact of the incident electron beam energy on the primary dose component of flattening filter free photon beams

    International Nuclear Information System (INIS)

    Kuess, Peter; Georg, Dietmar; Lechner, Wolfgang; Palmans, Hugo

    2016-01-01

    Purpose: For commercially available linear accelerators (Linacs), the electron energies of flattening filter free (FFF) and flattened (FF) beams are either identical or the electron energy of the FFF beam is increased to match the percentage depth dose curve (PDD) of the FF beam (in reference geometry). This study focuses on the primary dose components of FFF beams for both kinds of settings, studied on the same Linac. Methods: The measurements were conducted on a VersaHD Linac (Elekta, Crawley, UK) for both FF and FFF beams with nominal energies of 6 and 10 MV. In the clinical setting of the VersaHD, the energy of FFF M (Matched) beams is set to match the PDDs of the FF beams. In contrast the incident electron beam of the FFF U beam was set to the same energy as for the FF beam. Half value layers (HVLs) and a dual parameter beam quality specifier (DPBQS) were determined. Results: For the 6 MV FFF M beam, HVL and DPBQS values were very similar compared to those of the 6 MV FF beam, while for the 10 MV FFF M and FF beams, only %dd(10) x and HVL values were comparable (differences below 1.5%). This shows that matching the PDD at one depth does not guarantee other beam quality dependent parameters to be matched. For FFF U beams, all investigated beam quality specifiers were significantly different compared to those for FF beams of the same nominal accelerator potential. The DPBQS of the 6 MV FF and FFF M beams was equal within the measurement uncertainty and was comparable to published data of a machine with similar TPR 20,10 and %dd(10) x . In contrast to that, the DPBQS’s two parameters of the 10 MV FFF M beam were substantially higher compared to those for the 10 MV FF beam. Conclusions: PDD-matched FF and FFF beams of both nominal accelerator potentials were observed to have similar HVL values, indicating similarity of their primary dose components. Using the DPBQS revealed that the mean attenuation coefficient was found to be the same within the uncertainty of

  9. Data Filtering of Western Hemisphere GOES Wildfire ABBA Products

    Science.gov (United States)

    Theisen, M.; Prins, E.; Schmidt, C.; Reid, J. S.; Hunter, J.; Westphal, D.

    2002-05-01

    The Fire Locating and Modeling of Burning Emissions (FLAMBE') project was developed to model biomass burning emissions, transport, and radiative effects in real time. The model relies on data from the Geostationary Operational Environment Satellites (GOES-8, GOES-10), that is generated by the Wildfire Automated Biomass Burning Algorithm (WF ABBA). In an attempt to develop the most accurate modeling system the data set needs to be filtered to distinguish the true fire pixels from false alarms. False alarms occur due to reflection of solar radiation off of standing water, surface structure variances, and heat anomalies. The Reoccurring Fire Filtering algorithm (ReFF) was developed to address such false alarms by filtering data dependent on reoccurrence, location in relation to region and satellite, as well as heat intensity. WF ABBA data for the year 2000 during the peak of the burning season were analyzed using ReFF. The analysis resulted in a 45% decrease in North America and only a 15% decrease in South America, respectively, in total fire pixel occurrence. The lower percentage decrease in South America is a result of fires burning for longer periods of time, less surface variance, as well as an increase in heat intensity of fires for that region. Also fires are so prevalent in the region that multiple fires may coexist in the same 4-kilometer pixel.

  10. Neuropeptide FF increases M2 activation and self-renewal of adipose tissue macrophages

    Science.gov (United States)

    Waqas, Syed F. Hassnain; Hoang, Anh Cuong; Ampem, Grace; Azegrouz, Hind; Balogh, Lajos; Thuróczy, Julianna; Gerling, Ivan C.; Nam, Sorim; Lim, Jong-Seok; Martinez-Ibañez, Juncal; Real, José T.; Paschke, Stephan; Quillet, Raphaëlle; Ayachi, Safia; Simonin, Frédéric; Schneider, E. Marion; Brinkman, Jacqueline A.; Seroogy, Christine M.

    2017-01-01

    The quantity and activation state of adipose tissue macrophages (ATMs) impact the development of obesity-induced metabolic diseases. Appetite-controlling hormones play key roles in obesity; however, our understanding of their effects on ATMs is limited. Here, we have shown that human and mouse ATMs express NPFFR2, a receptor for the appetite-reducing neuropeptide FF (NPFF), and that NPFFR2 expression is upregulated by IL-4, an M2-polarizing cytokine. Plasma levels of NPFF decreased in obese patients and high-fat diet–fed mice and increased following caloric restriction. NPFF promoted M2 activation and increased the proliferation of murine and human ATMs. Both M2 activation and increased ATM proliferation were abolished in NPFFR2-deficient ATMs. Mechanistically, the effects of NPFF involved the suppression of E3 ubiquitin ligase RNF128 expression, resulting in enhanced stability of phosphorylated STAT6 and increased transcription of the M2 macrophage–associated genes IL-4 receptor α (Il4ra), arginase 1 (Arg1), IL-10 (Il10), and alkylglycerol monooxygenase (Agmo). NPFF induced ATM proliferation concomitantly with the increase in N-Myc downstream-regulated gene 2 (Ndrg2) expression and suppressed the transcription of Ifi200 cell-cycle inhibitor family members and MAF bZIP transcription factor B (Mafb), a negative regulator of macrophage proliferation. NPFF thus plays an important role in supporting healthy adipose tissue via the maintenance of metabolically beneficial ATMs. PMID:28581443

  11. An Atomistic Carbide-Derived Carbon Model Generated Using ReaxFF-Based Quenched Molecular Dynamics

    Directory of Open Access Journals (Sweden)

    Matthew W. Thompson

    2017-10-01

    Full Text Available We report a novel atomistic model of carbide-derived carbons (CDCs, which are nanoporous carbons with high specific surface areas, synthesis-dependent degrees of graphitization, and well-ordered, tunable porosities. These properties make CDCs viable substrates in several energy-relevant applications, such as gas storage media, electrochemical capacitors, and catalytic supports. These materials are heterogenous, non-ideal structures and include several important parameters that govern their performance. Therefore, a realistic model of the CDC structure is needed in order to study these systems and their nanoscale and macroscale properties with molecular simulation. We report the use of the ReaxFF reactive force field in a quenched molecular dynamics routine to generate atomistic CDC models. The pair distribution function, pore size distribution, and adsorptive properties of this model are reported and corroborated with experimental data. Simulations demonstrate that compressing the system after quenching changes the pore size distribution to better match the experimental target. Ring size distributions of this model demonstrate the prevalence of non-hexagonal carbon rings in CDCs. These effects may contrast the properties of CDCs against those of activated carbons with similar pore size distributions and explain higher energy densities of CDC-based supercapacitors.

  12. Current Conditions Risk Assessment for the 300-FF-5 Groundwater Operable Unit

    Energy Technology Data Exchange (ETDEWEB)

    Miley, Terri B.; Bunn, Amoret L.; Napier, Bruce A.; Peterson, Robert E.; Becker, James M.

    2007-11-01

    This report updates a baseline risk assessment for the 300 Area prepared in 1994. The update includes consideration of changes in contaminants of interest and in the environment that have occurred during the period of interim remedial action, i.e., 1996 to the present, as well as the sub-regions, for which no initial risk assessments have been conducted. In 1996, a record of decision (ROD) stipulated interim remedial action for groundwater affected by releases from 300 Area sources, as follows: (a) continued monitoring of groundwater that is contaminated above health-based levels to ensure that concentrations continue to decrease, and (b) institutional controls to ensure that groundwater use is restricted to prevent unacceptable exposure to groundwater contamination. In 2000, the groundwater beneath the two outlying sub-regions was added to the operable unit. In 2001, the first 5-year review of the ROD found that the interim remedy and remedial action objectives were still appropriate, although the review called for additional characterization activities. This report includes a current conditions baseline ecological and human health risk assessment using maximum concentrations in the environmental media of the 300-FF-5 Operable Unit and downstream conditions at the City of Richland, Washington. The scope for this assessment includes only current measured environmental concentrations and current use scenarios. Future environmental concentrations and future land uses are not considered in this assessment.

  13. Digital fabrication

    CERN Document Server

    2012-01-01

    The Winter 2012 (vol. 14 no. 3) issue of the Nexus Network Journal features seven original papers dedicated to the theme “Digital Fabrication”. Digital fabrication is changing architecture in fundamental ways in every phase, from concept to artifact. Projects growing out of research in digital fabrication are dependent on software that is entirely surface-oriented in its underlying mathematics. Decisions made during design, prototyping, fabrication and assembly rely on codes, scripts, parameters, operating systems and software, creating the need for teams with multidisciplinary expertise and different skills, from IT to architecture, design, material engineering, and mathematics, among others The papers grew out of a Lisbon symposium hosted by the ISCTE-Instituto Universitario de Lisboa entitled “Digital Fabrication – A State of the Art”. The issue is completed with four other research papers which address different mathematical instruments applied to architecture, including geometric tracing system...

  14. Remedial investigation/feasibility study work plan for the 300-FF-1 operable unit, Hanford Site, Richland, Washington

    International Nuclear Information System (INIS)

    1990-03-01

    Over 1,400 waste facilities have been identified on the Hanford Site. Most of the waste facilities are located within geographic areas on the Hanford Site that are referred to as the 100, 200, 300, 400, and 1100 areas. The purpose of this work plan is to document the project scoping process and to outline all remedial investigation/feasibility study (RI/FS) activities, to determine the nature and extent of the threat presented by releases of hazardous substances from the operable unit, and to evaluate proposed remedies for such releases. The goal of the 300-FF-1 remedial investigation (RI) is to provide sufficient information needed to conduct the feasibility study (FS), by determining the nature and extent of the threat to public health and the environment posed by releases of hazardous substances from 300-FF-1, and the performance of specific remedial technologies. 62 refs., 28 figs., 48 tabs

  15. Final Hazard Categorization for the Remediation of Six 300-FF-2 Operable Unit Solid Waste Burial Grounds

    International Nuclear Information System (INIS)

    Ludowise, J.D.

    2006-01-01

    This report provides the final hazard categorization (FHC) for the remediation of six solid waste disposal sites (referred to as burial grounds) located in the 300-FF-2 Operable Unit (OU) on the Hanford Site. These six sites (618-1, 618-2, 618-3, 618-7, 618-8, and 618-13 Burial Grounds) were determined to have a total radionuclide inventory (WCH 2005a, WCH 2005d, WCH 2005e and WCH 2006b) that exceeds the DOE-STD-1027 Category 3 threshold quantity (DOE 1997) and are the subject of this analysis. This FHC document examines the hazards, identifies appropriate controls to manage the hazards, and documents the FHC and commitments for the 300-FF-2 Burial Grounds Remediation Project

  16. Development of a ReaxFF reactive force field for ammonium nitrate and application to shock compression and thermal decomposition.

    Science.gov (United States)

    Shan, Tzu-Ray; van Duin, Adri C T; Thompson, Aidan P

    2014-02-27

    We have developed a new ReaxFF reactive force field parametrization for ammonium nitrate. Starting with an existing nitramine/TATB ReaxFF parametrization, we optimized it to reproduce electronic structure calculations for dissociation barriers, heats of formation, and crystal structure properties of ammonium nitrate phases. We have used it to predict the isothermal pressure-volume curve and the unreacted principal Hugoniot states. The predicted isothermal pressure-volume curve for phase IV solid ammonium nitrate agreed with electronic structure calculations and experimental data within 10% error for the considered range of compression. The predicted unreacted principal Hugoniot states were approximately 17% stiffer than experimental measurements. We then simulated thermal decomposition during heating to 2500 K. Thermal decomposition pathways agreed with experimental findings.

  17. A Probe-Compensated Helicoidal NF-FF Transformation for Aperture Antennas Using a Prolate Spheroidal Expansion

    Directory of Open Access Journals (Sweden)

    Amedeo Capozzoli

    2012-01-01

    Full Text Available A new probe-compensated near-field-far-field (NF-FF transformation for aperture antennas in a cylindrical scanning geometry is presented. Such a technique takes the advantage of the NF data acquisition made according to a very efficient sampling strategy along a helix and exploits a proper aperture field expansion based on the use of the prolate spheroidal wave functions (PSWFs, accounting for the a priori information on shape and size of the antenna under test. The unknown aperture field expansion coefficients of the PSWFs are evaluated from the acquired voltage samples by an inversion process using a regularized version of the singular value decomposition method. Experimental results on connected and disconnected radiating aperture antennas, including sum and difference patterns, show the effectiveness of the approach and, in particular, how it enables a serious reduction of the measurement points without impairing the FF estimation accuracy.

  18. Final Hazard Categorization for the Remediation of Six 300-FF-2 Operable Unit Solid Waste Burial Grounds

    Energy Technology Data Exchange (ETDEWEB)

    J. D. Ludowise

    2006-12-12

    This report provides the final hazard categorization (FHC) for the remediation of six solid waste disposal sites (referred to as burial grounds) located in the 300-FF-2 Operable Unit (OU) on the Hanford Site. These six sites (618-1, 618-2, 618-3, 618-7, 618-8, and 618-13 Burial Grounds) were determined to have a total radionuclide inventory (WCH 2005a, WCH 2005d, WCH 2005e and WCH 2006b) that exceeds the DOE-STD-1027 Category 3 threshold quantity (DOE 1997) and are the subject of this analysis. This FHC document examines the hazards, identifies appropriate controls to manage the hazards, and documents the FHC and commitments for the 300-FF-2 Burial Grounds Remediation Project.

  19. Convergent Filter Bases

    Directory of Open Access Journals (Sweden)

    Coghetto Roland

    2015-09-01

    Full Text Available We are inspired by the work of Henri Cartan [16], Bourbaki [10] (TG. I Filtres and Claude Wagschal [34]. We define the base of filter, image filter, convergent filter bases, limit filter and the filter base of tails (fr: filtre des sections.

  20. Molecular Dynamics Modeling of Carbon Nanotube Composite Fracture Using ReaxFF

    Science.gov (United States)

    Jensen, Benjamin D.; Wise, Kristopher E.; Odegard, Gregory M.

    2016-01-01

    Carbon nanotube (CNT) fiber reinforced composites with specific tensile strengths and moduli approaching those of aerospace grade carbon fiber composites have recently been reported. This achievement was enabled by the emerging availability of high N/tex yarns in kilometer-scale quantities. While the production of this yarn is an impressive advance, its strength is still much lower than that of the individual CNTs comprising the yarn. Closing this gap requires understanding load transfer between CNTs at the nanometer dimensional scale. This work uses reactive molecular dynamics simulations to gain an understanding at the nanometer scale of the key factors that determine CNT nanocomposite mechanical performance, and to place more realistic upper bounds on the target properties. While molecular dynamics simulations using conventional force fields can predict elastic properties, the ReaxFF reactive forcefield can also model fracture behavior because of its ability to accurately describe bond breaking and formation during a simulation. The upper and lower bounds of CNT composite properties are investigated by comparing systems composed of CNTs continuously connected across the periodic boundary with systems composed of finite length CNTs. These lengths, effectively infinite for the continuous tubes and an aspect ratio of 13 for the finite length case, result from practical limitations on the number of atoms that can be included in a simulation. Experimentally measured aspect ratios are typically on the order of 100,000, so the calculated results should represent upper and lower limits on experimental mechanical properties. Finally, the effect of various degrees of covalent crosslinking between the CNTs and amorphous carbon matrix is considered to identify the amount of CNT-matrix covalent bonding that maximizes overall composite properties.

  1. Geophysical Investigation of the 618-10 and 618-11 Burial Grounds, 300-FF-2 Operable Unit

    International Nuclear Information System (INIS)

    Bergstrom, K.A.; Bolin, D.J.; Mitchell, T.H.

    1997-09-01

    This document summarizes the results of geophysical investigations conducted at two radioactive solid waste burial grounds, 618-10 and 618-11. The burial grounds are located approximately 4.5 miles and 7 miles north of the 300 Area, respectively. These sites are within the 300-FF-2 Operable Unit, where geophysical techniques are being used to characterize the distribution of solid waste in the subsurface as part of the Limited Field Investigations for this operable unit

  2. A MEMS coupled resonator for frequency filtering in air

    KAUST Repository

    Ilyas, Saad; Jaber, Nizar; Younis, Mohammad I.

    2018-01-01

    We present design, fabrication, and characterization of a mechanically coupled MEMS H resonator capable of performing simultaneous mechanical amplification and filtering in air. The device comprises of two doubly clamped polyimide microbeams joined

  3. Miniaturized dielectric waveguide filters

    OpenAIRE

    Sandhu, MY; Hunter, IC

    2016-01-01

    Design techniques for a new class of integrated monolithic high-permittivity ceramic waveguide filters are presented. These filters enable a size reduction of 50% compared to air-filled transverse electromagnetic filters with the same unloaded Q-factor. Designs for Chebyshev and asymmetric generalised Chebyshev filter and a diplexer are presented with experimental results for an 1800 MHz Chebyshev filter and a 1700 MHz generalised Chebyshev filter showing excellent agreement with theory.

  4. Multicentre knowledge sharing and planning/dose audit on flattening filter free beams for SBRT lung

    DEFF Research Database (Denmark)

    Hansen, C. R.; Sykes, J. R.; Barber, J.

    2015-01-01

    When implementing new technology into clinical practice, there will always be a need for large knowledge gain. The aim of this study was twofold, (I) audit the treatment planning and dose delivery of Flattening Filter Free (FFF) beam technology for Stereotactic Body Radiation Therapy (SBRT) of lung...... tumours across a range of treatment planning systems compared to the conventional Flatting Filter (FF) beams, (II) investigate how sharing knowledge between centres of different experience can improve plan quality. All vendor/treatment planning system (TPS) combinations investigated were able to produce...

  5. Programmable Baseband Filter for Multistandard Mobile Phones

    DEFF Research Database (Denmark)

    Jensen, Rasmus Glarborg; Christensen, Kåre Tais; Bruun, Erik

    2003-01-01

    of the input transconductor. The entire filter consumes between 2.5 mW and 7.5 mW, depending on the desired noise performance. It is implemented in a standard 0.25 mum CMOS process. A test circuit has been developed and fabricated and measurements show that both the required programmability and the required...

  6. Scandium/carbon filters for soft x rays

    NARCIS (Netherlands)

    Artioukov, IA; Kasyanov, YS; Kopylets, IA; Pershin, YP; Romanova, SA

    2003-01-01

    This Note deals with thin-film soft x-ray filters for operation at the wavelengths near carbon K edge (similar to4.5 nm). The filters were fabricated by magnetron sputtering deposition of thin layers of scandium (total thickness 0.1-0.2 mum) onto films of polypropylene (thickness 1.5 mum) and

  7. Final hazard classification and auditable safety analysis for the 300-FF-1 Operable Unit liquid waste sites, landfills, and Burial Ground 618-4

    International Nuclear Information System (INIS)

    Adam, W.J.; Larson, A.R.

    1996-12-01

    This document provides the hazard categorizations and classifications for the activities associated with the 300-FF-1 Operable Unit (OU) remediation. Categories and classifications presented are applicable only to the 300-FF-1 OU waste sites specifically listed in the inventory. The purpose of this remedial action is to remove contaminated soil, debris, and solid waste from liquid waste sites, landfills, and Burial Ground 618-4 within the 300-FF-1 OU. Resulting waste from this project will be sent to the Environmental Restoration Disposal Facility (ERDF) in the 200 West Area. The 300-FF-1 OU is part of the 300 Area of the Hanford Site and is next to the Columbia River. The objective of this remedial action is to reduce contamination at these waste sites to levels that are acceptable for industrial purposes. Specific remedial objectives (cleanup goals) for each contaminant of concern (COC) are provided in a table, along with the maximum soil concentration detected

  8. Selection vector filter framework

    Science.gov (United States)

    Lukac, Rastislav; Plataniotis, Konstantinos N.; Smolka, Bogdan; Venetsanopoulos, Anastasios N.

    2003-10-01

    We provide a unified framework of nonlinear vector techniques outputting the lowest ranked vector. The proposed framework constitutes a generalized filter class for multichannel signal processing. A new class of nonlinear selection filters are based on the robust order-statistic theory and the minimization of the weighted distance function to other input samples. The proposed method can be designed to perform a variety of filtering operations including previously developed filtering techniques such as vector median, basic vector directional filter, directional distance filter, weighted vector median filters and weighted directional filters. A wide range of filtering operations is guaranteed by the filter structure with two independent weight vectors for angular and distance domains of the vector space. In order to adapt the filter parameters to varying signal and noise statistics, we provide also the generalized optimization algorithms taking the advantage of the weighted median filters and the relationship between standard median filter and vector median filter. Thus, we can deal with both statistical and deterministic aspects of the filter design process. It will be shown that the proposed method holds the required properties such as the capability of modelling the underlying system in the application at hand, the robustness with respect to errors in the model of underlying system, the availability of the training procedure and finally, the simplicity of filter representation, analysis, design and implementation. Simulation studies also indicate that the new filters are computationally attractive and have excellent performance in environments corrupted by bit errors and impulsive noise.

  9. Application of HTSC-thin films in microwave bandpass filters

    International Nuclear Information System (INIS)

    Jha, A.R.

    1993-01-01

    This paper reveals unique performance capabilities of High-Temperature Superconducting Thin-Film (HTSCTFs) for possible applications in microwave bandpass filters (BPFs). Microwave filters fabricated with HTSCTFs have demonstrated lowest insertion loss, highest rejection, and sharpest skirt selectivity. Thin films of Yttrium Barium Copper Oxide (YBCO), Bismuth Strontium Calcium Copper Oxide (BSCCO) and Thallium Calcium Barium Copper Oxide (TCBCO) will be most attractive for filters

  10. Filters for mobile radio from high Tc ceramic superconductors

    International Nuclear Information System (INIS)

    Peterson, G.E.; Wong, E.; Alford, N.McN.

    1990-01-01

    Mobile radio frequencies lie between 30 MHz and 1,000 MHz. This frequency range is ideal for ceramic high T c superconductors. We have designed Chebyshev, Butterworth and interdigital filters that can employ high T c superconductors in the form of rods, tubes and helices. In general, the performance of these filters at milliwatt power levels is excellent. We will describe fabrication of the superconductors and filter design

  11. Pressure transients across HEPA filters

    International Nuclear Information System (INIS)

    Gregory, W.; Reynolds, G.; Ricketts, C.; Smith, P.R.

    1977-01-01

    Nuclear fuel cycle facilities require ventilation for health and safety reasons. High efficiency particulate air (HEPA) filters are located within ventilation systems to trap radioactive dust released in reprocessing and fabrication operations. Pressure transients within the air cleaning systems may be such that the effectiveness of the filtration system is questioned under certain accident conditions. These pressure transients can result from both natural and man-caused phenomena: atmospheric pressure drop caused by a tornado or explosions and nuclear excursions initiate pressure pulses that could create undesirable conditions across HEPA filters. Tornado depressurization is a relatively slow transient as compared to pressure pulses that result from combustible hydrogen-air mixtures. Experimental investigation of these pressure transients across air cleaning equipment has been undertaken by Los Alamos Scientific Laboratory and New Mexico State University. An experimental apparatus has been constructed to impose pressure pulses across HEPA filters. The experimental equipment is described as well as preliminary results using variable pressurization rates. Two modes of filtration of an aerosol injected upstream of the filter is examined. A laser instrumentation for measuring the aerosol release, during the transient, is described

  12. Recirculating electric air filter

    Science.gov (United States)

    Bergman, W.

    1985-01-09

    An electric air filter cartridge has a cylindrical inner high voltage electrode, a layer of filter material, and an outer ground electrode formed of a plurality of segments moveably connected together. The outer electrode can be easily opened to remove or insert filter material. Air flows through the two electrodes and the filter material and is exhausted from the center of the inner electrode.

  13. Passive Power Filters

    CERN Document Server

    Künzi, R.

    2015-06-15

    Power converters require passive low-pass filters which are capable of reducing voltage ripples effectively. In contrast to signal filters, the components of power filters must carry large currents or withstand large voltages, respectively. In this paper, three different suitable filter struc tures for d.c./d.c. power converters with inductive load are introduced. The formulas needed to calculate the filter components are derived step by step and practical examples are given. The behaviour of the three discussed filters is compared by means of the examples. P ractical aspects for the realization of power filters are also discussed.

  14. Filter replacement lifetime prediction

    Science.gov (United States)

    Hamann, Hendrik F.; Klein, Levente I.; Manzer, Dennis G.; Marianno, Fernando J.

    2017-10-25

    Methods and systems for predicting a filter lifetime include building a filter effectiveness history based on contaminant sensor information associated with a filter; determining a rate of filter consumption with a processor based on the filter effectiveness history; and determining a remaining filter lifetime based on the determined rate of filter consumption. Methods and systems for increasing filter economy include measuring contaminants in an internal and an external environment; determining a cost of a corrosion rate increase if unfiltered external air intake is increased for cooling; determining a cost of increased air pressure to filter external air; and if the cost of filtering external air exceeds the cost of the corrosion rate increase, increasing an intake of unfiltered external air.

  15. Evaluation of self-contained HEPA filter

    Energy Technology Data Exchange (ETDEWEB)

    Arndt, T.E. [Westinghouse Hanford Company, Richland, WA (United States)

    1995-02-01

    This paper presents the results of an evaluation of a self-contained high-efficiency particulate air filter (SHEPA) used in nuclear applications. A SCHEPA consists of filter medium encapsulated in a casing that is part of the system boundary. The SCHEPA filter serves as a combination of filter housing and filter. The filter medium is attached directly to the casing using adhesive as a bonding agent. A cylindrical connection in the middle of the end caps connects the filter assembly to adjoining ductwork. The SCHEPA must perform the functions of a filter housing, filter frame, and filter. It was recognized that the codes and standards do not address the SCHEPA specifically. Therefore, the investigation evaluated the SCHEPA against current codes and standards related to the functional requirements of an air-cleaning system. The specific standards used are required by DOE Order 6430.1A{sup 1} and include ASME N509{sup 3}, ASME N510{sup 4}, ERDA 76-21{sup 5}, MIL-F-51068F{sup 6}, NFPA 90A, {sup 7} and NFPA 91{sup 8}. The evaluation does not address whether the SCHEPA as a standard (off-the-shelf) filter could be upgraded to meet the current code requirements for an air-cleaning unit. The evaluation also did not consider how the SCHEPA was used in a system (e.g., whether it was under positive or negative pressure or whether it served as an air inlet filter to prevent contamination releases under system pressurization). The results of the evaluation show that, the SCHEPA filter does not meet design, fabrication, testing, and documentation requirements of ASME N509{sup 3} and ASME N510{sup 4}. The paper will identify these deficiencies. Specific exhaust system requirements and application should be considered when an evaluation of the SCHEPA filter is being performed in existing systems. When new designs are being comtemplated, other types of HEPA filter housings can be used in lieu of the SCHEPA filter.

  16. [18F]F15599, a novel 5-HT1A receptor agonist, as a radioligand for PET neuroimaging.

    Science.gov (United States)

    Lemoine, Laëtitia; Verdurand, Mathieu; Vacher, Bernard; Blanc, Elodie; Le Bars, Didier; Newman-Tancredi, Adrian; Zimmer, Luc

    2010-03-01

    The serotonin-1A (5-HT(1A)) receptor is implicated in the pathophysiology of major neuropsychiatric disorders. Thus, the functional imaging of 5-HT(1A) receptors by positron emission tomography (PET) may contribute to the understanding of its role in those pathologies and their therapeutics. These receptors exist in high- and low-affinity states and it is proposed that agonists bind preferentially to the high-affinity state of the receptor and therefore could provide a measure of the functional 5-HT(1A) receptors. Since all clinical PET 5-HT(1A) radiopharmaceuticals are antagonists, it is of great interest to develop a( 18)F labelled agonist. F15599 (3-chloro-4-fluorophenyl-(4-fluoro-4{[(5-methyl-pyrimidin-2-ylmethyl)-amino]-methyl}-piperidin-1-yl)-methanone) is a novel ligand with high affinity and selectivity for 5-HT(1A) receptors and is currently tested as an antidepressant. In pharmacological tests in rat, it exhibits preferential agonist activity at post-synaptic 5-HT(1A) receptors in cortical brain regions. Here, its nitro-precursor was synthesised and radiolabelled via a fluoronucleophilic substitution. Radiopharmacological evaluations included in vitro and ex vivo autoradiography in rat brain and PET scans on rats and cats. Results were compared with simultaneous studies using [(18)F]MPPF, a validated 5-HT(1A) antagonist radiopharmaceutical. The chemical and radiochemical purities of [(18)F]F15599 were >98%. In vitro [(18)F]F15599 binding was consistent with the known 5-HT(1A) receptors distribution (hippocampus, dorsal raphe nucleus, and notably cortical areas) and addition of Gpp(NH)p inhibited [(18)F]F15599 binding, consistent with a specific binding to G protein-coupled receptors. In vitro binding of [(18)F]F15599 was blocked by WAY100635 and 8-OH-DPAT, respectively, prototypical 5-HT(1A) antagonist and agonist. The ex vivo and in vivo studies demonstrated that the radiotracer readily entered the rat and the cat brain and generated few brain

  17. MEMS Coupled Resonator for Filter Application in Air

    KAUST Repository

    Ilyas, Saad; Jaber, Nizar; Younis, Mohammad I.

    2017-01-01

    We present a mechanically coupled MEMS H resonator capable of performing simultaneous amplification and filter operation in air. The device comprises of two doubly clamped polyimide microbeams joined through the middle by a coupling beam of the same size. The resonator is fabricated via a multilayer surface micromachining process. A special fabrication process and device design is employed to enable the device's operation in air and to achieve mechanical amplification of the output response. Moreover, mixed-frequency excitation is used to demonstrate a tunable wide band filter. The device design combined with the mixed-frequency excitation is used to demonstrate simultaneous amplification and filtering in air.

  18. MEMS Coupled Resonator for Filter Application in Air

    KAUST Repository

    Ilyas, Saad

    2017-11-03

    We present a mechanically coupled MEMS H resonator capable of performing simultaneous amplification and filter operation in air. The device comprises of two doubly clamped polyimide microbeams joined through the middle by a coupling beam of the same size. The resonator is fabricated via a multilayer surface micromachining process. A special fabrication process and device design is employed to enable the device\\'s operation in air and to achieve mechanical amplification of the output response. Moreover, mixed-frequency excitation is used to demonstrate a tunable wide band filter. The device design combined with the mixed-frequency excitation is used to demonstrate simultaneous amplification and filtering in air.

  19. Optimization of filter loading

    International Nuclear Information System (INIS)

    Turney, J.H.; Gardiner, D.E.; Sacramento Municipal Utility District, Herald, CA)

    1985-01-01

    The introduction of 10 CFR Part 61 has created potential difficulties in the disposal of spent cartridge filters. When this report was prepared, Rancho Seco had no method of packaging and disposing of class B or C filters. This work examined methods to minimize the total operating cost of cartridge filters while maintaining them below the class A limit. It was found that by encapsulating filters in cement the filter operating costs could be minimized

  20. Treatment/Disposal Plan for Drummed Waste from the 300-FF-1 Operable Unit, 618-4 Burial Ground

    International Nuclear Information System (INIS)

    Lerch, J.A.

    1999-01-01

    The objective of this plan is to support selection of a safe, environmentally responsible, and cost-effective treatment and disposal method for drums containing depleted uranium metal chips submerged in oil that have been and will be excavated from the 618-4 Burial Ground. Remediation of the 300-FF-1 Operable Unit, 618-4 Burial Ground was initiated in fiscal year (FY) 1998 as an excavation and removal operation. Routine processes were established to excavate and ship contaminated soil and debris to the Environmental Restoration Disposal Facility (ERDF) for disposal

  1. ReaxFF Grand Canonical Monte Carlo simulation of adsorption and dissociation of oxygen on platinum (111)

    Science.gov (United States)

    Valentini, Paolo; Schwartzentruber, Thomas E.; Cozmuta, Ioana

    2011-12-01

    Atomic-level Grand Canonical Monte Carlo (GCMC) simulations equipped with a reactive force field (ReaxFF) are used to study atomic oxygen adsorption on a Pt(111) surface. The off-lattice GCMC calculations presented here rely solely on the interatomic potential and do not necessitate the pre-computation of surface adlayer structures and their interpolation. As such, they provide a predictive description of adsorbate phases. In this study, validation is obtained with experimental evidence (steric heats of adsorption and isotherms) as well as DFT-based state diagrams available in the literature. The ReaxFF computed steric heats of adsorption agree well with experimental data, and this study clearly shows that indirect dissociative adsorption of O2 on Pt(111) is an activated process at non-zero coverages, with an activation energy that monotonically increases with coverage. At a coverage of 0.25 ML, a highly ordered p(2 × 2) adlayer is found, in agreement with several low-energy electron diffraction observations. Isotherms obtained from the GCMC simulations compare qualitatively and quantitatively well with previous DFT-based state diagrams, but are in disagreement with the experimental data sets available. ReaxFF GCMC simulations at very high coverages show that O atoms prefer to bind in fcc hollow sites, at least up to 0.8 ML considered in the present work. At moderate coverages, little to no disorder appears in the Pt lattice. At high coverages, some Pt atoms markedly protrude out of the surface plane. This observation is in qualitative agreement with recent STM images of an oxygen covered Pt surface. The use of the GCMC technique based on a transferable potential is particularly valuable to produce more realistic systems (adsorbent and adsorbate) to be used in subsequent dynamical simulations (Molecular Dynamics) to address recombination reactions (via either Eley-Rideal or Langmuir-Hinshelwood mechanisms) on variously covered surfaces. By using GCMC and Molecular

  2. A probabilistic approach of the Flash Flood Early Warning System (FF-EWS) in Catalonia based on radar ensemble generation

    Science.gov (United States)

    Velasco, David; Sempere-Torres, Daniel; Corral, Carles; Llort, Xavier; Velasco, Enrique

    2010-05-01

    Early Warning Systems (EWS) are commonly identified as the most efficient tools in order to improve the preparedness and risk management against heavy rains and Flash Floods (FF) with the objective of reducing economical losses and human casualties. In particular, flash floods affecting torrential Mediterranean catchments are a key element to be incorporated within operational EWSs. The characteristic high spatial and temporal variability of the storms requires high-resolution data and methods to monitor/forecast the evolution of rainfall and its hydrological impact in small and medium torrential basins. A first version of an operational FF-EWS has been implemented in Catalonia (NE Spain) under the name of EHIMI system (Integrated Tool for Hydrometeorological Forecasting) with the support of the Catalan Water Agency (ACA) and the Meteorological Service of Catalonia (SMC). Flash flood warnings are issued based on radar-rainfall estimates. Rainfall estimation is performed on radar observations with high spatial and temporal resolution (1km2 and 10 minutes) in order to adapt the warning scale to the 1-km grid of the EWS. The method is based on comparing observed accumulated rainfall against rainfall thresholds provided by the regional Intensity-Duration-Frequency (IDF) curves. The so-called "aggregated rainfall warning" at every river cell is obtained as the spatially averaged rainfall over its associated upstream draining area. Regarding the time aggregation of rainfall, the critical duration is thought to be an accumulation period similar to the concentration time of each cachtment. The warning is issued once the forecasted rainfall accumulation exceeds the rainfall thresholds mentioned above, which are associated to certain probability of occurrence. Finally, the hazard warning is provided and shown to the decision-maker in terms of exceeded return periods at every river cell covering the whole area of Catalonia. The objective of the present work includes the

  3. Effects of additional isoscalar vector bosons in e+e-→ff-bar processes at the TRISTAN and LEP energies

    International Nuclear Information System (INIS)

    Pankov, A.A.; Gershtejn, S.S.; Likhoded, A.A.; Yushchenko, O.P.

    1991-01-01

    The phenomenological manifestation of the additional Y(Y L ) boson arising in the models with the composite structure of electroweak interactions is studied for the process e + e - →ff-bar at the TRISTAN and LEP energies. It is shown that the presence of the additional isoscalar boson, yields a measurable effect in the cross-section of e + e - →μ + μ - (hadrons) processes at LEP. This effect in the muon and hadron cross-sections at the energies M Z ±Γ Z /2 can be ∼1.5-2% for small values of the γ-Y-mixing parameter. 13 refs

  4. Electrical resistivity and dechanneling study of radiation defects in iron by 235U fission fragments (F.F.). I - Study of damage induced by F.F. Irradiation at 20K. II - Recovery of radiation defects

    International Nuclear Information System (INIS)

    Lorenzelli, Nicole.

    1979-09-01

    The irradiation by 235 U fission fragments (F.F.) of two iron samples of different purities (the essential impurity being C) have been studied. Comparative measurements of electrical resistivity and dechanneling of 5 MeV α-particles have been made during irradiation and subsequent recovery. The production curves provide, from their slopes at the origin, the following informations: 14000 Frenkel pairs by F.F. (from electrical resistivity); aggregate's rate: 5 per mille (from dechanneling). These curves do not follow a simple law: it seems that one observes the superposition of two saturation mechanisms with very different kinetics. During recovery, the same stages that after electrons or neutrons irradiation are observed, but with very different proportions. Dechanneling puts in evidence: -great modifications in cementite precipitation of an Fe-C alloy, by irradiation; - the recovery stage of loops starting from 800 K and with an activation energy approximately 1 eV; - the preponderant effect of clustering during stages Isub(D), Isub(E), IIsub(C) and IIsub(D) [fr

  5. SU-E-T-670: Radiotherapy Vault Shielding Evaluation Method for a Flattening Filter-Free (FFF) Linac-Practical Considerations and Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Mihailidis, D [CAMC Cancer Center-Alliance Oncology and West Virginia University, Charleston, WV (United States)

    2015-06-15

    Purpose: To date, there isn’t formal approach for flattening filter-free (FFF) linac vault shielding evaluation, thus, we propose an extension to NCRP#151 to accommodate the recent large number of FFF linac installations.Methods and Materials: We extended the approach in NCRP#151 to design two Truebeam vaults in our new cancer center for hypofractionated treatments. Monte Carlo calculations have characterized primary, scattered, leakage and neutron radiations from FFF-modes. These calculations have shown that: a) FFF primary beam is softer on the central-axis compared to flattening filtered (FF), b) the lateral dose profile is peaked on the central axis and less integral target current is required to generate the same tumor dose with the FF beam. Thus, the TVLs for FFF mode are smaller than those of the FF mode and the scatter functions of the FF mode (NCRP#151) may not be appropriate for FFF-mode, c) the neutron source strength and fluence for 18X-FFF is smaller than 18X-FF, but it is not of a concern here, no 18X-FFF-mode is available on the linac under investigation. Results: These barrier thickness are smaller (12% reduction on the average) than those computed for conventional FF mode with same realistic primary workload since, the primary TVLs used here are smaller and the WL is smaller than the conventional (almost half reduced), keeping the TADR in tolerance. Conclusions: A comprehensive method for shielding barrier calculations based on dedicated data for FFF-mode linacs is highly desired. Meanwhile, we provide an extension to NCRP#151 to accommodate the shielding design of such installations. It is also shown that if a vault is already designed for IMRT/VMAT and SABR hypofractionated treatments with FFF-mode linac, the vault can also be used for a FFF mode linac replacement, leaving some leeway for slightly higher workload on the FFF linac.

  6. SU-E-T-670: Radiotherapy Vault Shielding Evaluation Method for a Flattening Filter-Free (FFF) Linac-Practical Considerations and Recommendations

    International Nuclear Information System (INIS)

    Mihailidis, D

    2015-01-01

    Purpose: To date, there isn’t formal approach for flattening filter-free (FFF) linac vault shielding evaluation, thus, we propose an extension to NCRP#151 to accommodate the recent large number of FFF linac installations.Methods and Materials: We extended the approach in NCRP#151 to design two Truebeam vaults in our new cancer center for hypofractionated treatments. Monte Carlo calculations have characterized primary, scattered, leakage and neutron radiations from FFF-modes. These calculations have shown that: a) FFF primary beam is softer on the central-axis compared to flattening filtered (FF), b) the lateral dose profile is peaked on the central axis and less integral target current is required to generate the same tumor dose with the FF beam. Thus, the TVLs for FFF mode are smaller than those of the FF mode and the scatter functions of the FF mode (NCRP#151) may not be appropriate for FFF-mode, c) the neutron source strength and fluence for 18X-FFF is smaller than 18X-FF, but it is not of a concern here, no 18X-FFF-mode is available on the linac under investigation. Results: These barrier thickness are smaller (12% reduction on the average) than those computed for conventional FF mode with same realistic primary workload since, the primary TVLs used here are smaller and the WL is smaller than the conventional (almost half reduced), keeping the TADR in tolerance. Conclusions: A comprehensive method for shielding barrier calculations based on dedicated data for FFF-mode linacs is highly desired. Meanwhile, we provide an extension to NCRP#151 to accommodate the shielding design of such installations. It is also shown that if a vault is already designed for IMRT/VMAT and SABR hypofractionated treatments with FFF-mode linac, the vault can also be used for a FFF mode linac replacement, leaving some leeway for slightly higher workload on the FFF linac

  7. A Glitch-Free Novel DET-FF in 22 nm CMOS for Low-Power Application

    Directory of Open Access Journals (Sweden)

    Sumitra Singar

    2018-01-01

    Full Text Available Dual edge triggered (DET techniques are most liked choice for the researchers in the field of digital VLSI design because of its high-performance and low-power consumption standard. Dual edge triggered techniques give the similar throughput at half of the clock frequency as compared to the single edge triggered (SET techniques. Dual edge triggered techniques can reduce the 50% power consumption and increase the total system power savings. The low-power glitch-free novel dual edge triggered flip-flop (DET-FF design is proposed in this paper. Still now, existing DET-FF designs are constructed by using either C-element circuit or 1P-2N structure or 2P-1N structure, but the proposed novel design is designed by using the combination of C-element circuit and 2P-1N structure. In this design, if any glitch affects one of the structures, then it is nullified by the other structure. To control the input loading, the two circuits are merged to share the transistors connected to the input. In the proposed design, we have used an internal dual feedback structure. The proposed design reduces the delay and power consumption and increases the speed and efficiency of the system.

  8. Laboratory for filter testing

    Energy Technology Data Exchange (ETDEWEB)

    Paluch, W.

    1987-07-01

    Filters used for mine draining in brown coal surface mines are tested by the Mine Draining Department of Poltegor. Laboratory tests of new types of filters developed by Poltegor are analyzed. Two types of tests are used: tests of scale filter models and tests of experimental units of new filters. Design and operation of the test stands used for testing mechanical properties and hydraulic properties of filters for coal mines are described: dimensions, pressure fluctuations, hydraulic equipment. Examples of testing large-diameter filters for brown coal mines are discussed.

  9. Evaluation of treatment plan quality of IMRT and VMAT with and without flattening filter using Pareto optimal fronts.

    Science.gov (United States)

    Lechner, Wolfgang; Kragl, Gabriele; Georg, Dietmar

    2013-12-01

    To investigate the differences in treatment plan quality of IMRT and VMAT with and without flattening filter using Pareto optimal fronts, for two treatment sites of different anatomic complexity. Pareto optimal fronts (POFs) were generated for six prostate and head-and-neck cancer patients by stepwise reduction of the constraint (during the optimization process) of the primary organ-at-risk (OAR). 9-static field IMRT and 360°-single-arc VMAT plans with flattening filter (FF) and without flattening filter (FFF) were compared. The volume receiving 5 Gy or more (V5 Gy) was used to estimate the low dose exposure. Furthermore, the number of monitor units (MUs) and measurements of the delivery time (T) were used to assess the efficiency of the treatment plans. A significant increase in MUs was found when using FFF-beams while the treatment plan quality was at least equivalent to the FF-beams. T was decreased by 18% for prostate for IMRT with FFF-beams and by 4% for head-and-neck cases, but increased by 22% and 16% for VMAT. A reduction of up to 5% of V5 Gy was found for IMRT prostate cases with FFF-beams. The evaluation of the POFs showed an at least comparable treatment plan quality of FFF-beams compared to FF-beams for both treatment sites and modalities. For smaller targets the advantageous characteristics of FFF-beams could be better exploited. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  10. Sensory Pollution from Bag Filters, Carbon Filters and Combinations

    DEFF Research Database (Denmark)

    Bekö, Gabriel; Clausen, Geo; Weschler, Charles J.

    2008-01-01

    by an upstream pre-filter (changed monthly), an EU7 filter protected by an upstream activated carbon (AC) filter, and EU7 filters with an AC filter either downstream or both upstream and downstream. In addition, two types of stand-alone combination filters were evaluated: a bag-type fiberglass filter...... that contained AC and a synthetic fiber cartridge filter that contained AC. Air that had passed through used filters was most acceptable for those sets in which an AC filter was used downstream of the particle filter. Comparable air quality was achieved with the stand-alone bag filter that contained AC...

  11. HEPA Filter Vulnerability Assessment

    International Nuclear Information System (INIS)

    GUSTAVSON, R.D.

    2000-01-01

    This assessment of High Efficiency Particulate Air (HEPA) filter vulnerability was requested by the USDOE Office of River Protection (ORP) to satisfy a DOE-HQ directive to evaluate the effect of filter degradation on the facility authorization basis assumptions. Within the scope of this assessment are ventilation system HEPA filters that are classified as Safety-Class (SC) or Safety-Significant (SS) components that perform an accident mitigation function. The objective of the assessment is to verify whether HEPA filters that perform a safety function during an accident are likely to perform as intended to limit release of hazardous or radioactive materials, considering factors that could degrade the filters. Filter degradation factors considered include aging, wetting of filters, exposure to high temperature, exposure to corrosive or reactive chemicals, and exposure to radiation. Screening and evaluation criteria were developed by a site-wide group of HVAC engineers and HEPA filter experts from published empirical data. For River Protection Project (RPP) filters, the only degradation factor that exceeded the screening threshold was for filter aging. Subsequent evaluation of the effect of filter aging on the filter strength was conducted, and the results were compared with required performance to meet the conditions assumed in the RPP Authorization Basis (AB). It was found that the reduction in filter strength due to aging does not affect the filter performance requirements as specified in the AB. A portion of the HEPA filter vulnerability assessment is being conducted by the ORP and is not part of the scope of this study. The ORP is conducting an assessment of the existing policies and programs relating to maintenance, testing, and change-out of HEPA filters used for SC/SS service. This document presents the results of a HEPA filter vulnerability assessment conducted for the River protection project as requested by the DOE Office of River Protection

  12. Alkali metal for ultraviolet band-pass filter

    Science.gov (United States)

    Mardesich, Nick (Inventor); Fraschetti, George A. (Inventor); Mccann, Timothy A. (Inventor); Mayall, Sherwood D. (Inventor); Dunn, Donald E. (Inventor); Trauger, John T. (Inventor)

    1993-01-01

    An alkali metal filter having a layer of metallic bismuth deposited onto the alkali metal is provided. The metallic bismuth acts to stabilize the surface of the alkali metal to prevent substantial surface migration from occurring on the alkali metal, which may degrade optical characteristics of the filter. To this end, a layer of metallic bismuth is deposited by vapor deposition over the alkali metal to a depth of approximately 5 to 10 A. A complete alkali metal filter is described along with a method for fabricating the alkali metal filter.

  13. Fabricated Elastin.

    Science.gov (United States)

    Yeo, Giselle C; Aghaei-Ghareh-Bolagh, Behnaz; Brackenreg, Edwin P; Hiob, Matti A; Lee, Pearl; Weiss, Anthony S

    2015-11-18

    The mechanical stability, elasticity, inherent bioactivity, and self-assembly properties of elastin make it a highly attractive candidate for the fabrication of versatile biomaterials. The ability to engineer specific peptide sequences derived from elastin allows the precise control of these physicochemical and organizational characteristics, and further broadens the diversity of elastin-based applications. Elastin and elastin-like peptides can also be modified or blended with other natural or synthetic moieties, including peptides, proteins, polysaccharides, and polymers, to augment existing capabilities or confer additional architectural and biofunctional features to compositionally pure materials. Elastin and elastin-based composites have been subjected to diverse fabrication processes, including heating, electrospinning, wet spinning, solvent casting, freeze-drying, and cross-linking, for the manufacture of particles, fibers, gels, tubes, sheets and films. The resulting materials can be tailored to possess specific strength, elasticity, morphology, topography, porosity, wettability, surface charge, and bioactivity. This extraordinary tunability of elastin-based constructs enables their use in a range of biomedical and tissue engineering applications such as targeted drug delivery, cell encapsulation, vascular repair, nerve regeneration, wound healing, and dermal, cartilage, bone, and dental replacement. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Nanoscale freestanding gratings for ultraviolet blocking filters

    Energy Technology Data Exchange (ETDEWEB)

    van Beek, J.T.; Fleming, R.C.; Hindle, P.S.; Prentiss, J.D.; Schattenburg, M.L. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Ritzau, S. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    1998-11-01

    Ultraviolet (UV) blocking filters are needed for atomic flux imaging in environments where high levels of ultraviolet radiation are present. Freestanding gratings are a promising candidate for UV filtering. They have a high aspect ratio ({approximately}13), narrow ({approximately}40 nm) slots, and effectively block UV radiation. The grating fabrication process makes use of several etching, electroplating, and lithographic steps and includes an optional step to plug pinholes induced by particles during processing. Gratings were successfully manufactured and tested. Measured UV transmissions of {approximately}10{sup {minus}5} and particle transmissions of {approximately}10{percent} are in agreement with theoretical predictions. {copyright} {ital 1998 American Vacuum Society.}

  15. Bias aware Kalman filters

    DEFF Research Database (Denmark)

    Drecourt, J.-P.; Madsen, H.; Rosbjerg, Dan

    2006-01-01

    This paper reviews two different approaches that have been proposed to tackle the problems of model bias with the Kalman filter: the use of a colored noise model and the implementation of a separate bias filter. Both filters are implemented with and without feedback of the bias into the model state....... The colored noise filter formulation is extended to correct both time correlated and uncorrelated model error components. A more stable version of the separate filter without feedback is presented. The filters are implemented in an ensemble framework using Latin hypercube sampling. The techniques...... are illustrated on a simple one-dimensional groundwater problem. The results show that the presented filters outperform the standard Kalman filter and that the implementations with bias feedback work in more general conditions than the implementations without feedback. 2005 Elsevier Ltd. All rights reserved....

  16. Simon-nitinol filter

    International Nuclear Information System (INIS)

    Simon, M.; Kim, D.; Porter, D.H.; Kleshinski, S.

    1989-01-01

    This paper discusses a filter that exploits the thermal shape-memory properties of the nitinol alloy to achieve an optimized filter shape and a fine-bore introducer. Experimental methods and materials are given and results are analyzed

  17. MST Filterability Tests

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Duignan, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-03-12

    The Savannah River Site (SRS) is currently treating radioactive liquid waste with the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction Unit (MCU). The low filter flux through the ARP has limited the rate at which radioactive liquid waste can be treated. Recent filter flux has averaged approximately 5 gallons per minute (gpm). Salt Batch 6 has had a lower processing rate and required frequent filter cleaning. Savannah River Remediation (SRR) has a desire to understand the causes of the low filter flux and to increase ARP/MCU throughput. In addition, at the time the testing started, SRR was assessing the impact of replacing the 0.1 micron filter with a 0.5 micron filter. This report describes testing of MST filterability to investigate the impact of filter pore size and MST particle size on filter flux and testing of filter enhancers to attempt to increase filter flux. The authors constructed a laboratory-scale crossflow filter apparatus with two crossflow filters operating in parallel. One filter was a 0.1 micron Mott sintered SS filter and the other was a 0.5 micron Mott sintered SS filter. The authors also constructed a dead-end filtration apparatus to conduct screening tests with potential filter aids and body feeds, referred to as filter enhancers. The original baseline for ARP was 5.6 M sodium salt solution with a free hydroxide concentration of approximately 1.7 M.3 ARP has been operating with a sodium concentration of approximately 6.4 M and a free hydroxide concentration of approximately 2.5 M. SRNL conducted tests varying the concentration of sodium and free hydroxide to determine whether those changes had a significant effect on filter flux. The feed slurries for the MST filterability tests were composed of simple salts (NaOH, NaNO2, and NaNO3) and MST (0.2 – 4.8 g/L). The feed slurry for the filter enhancer tests contained simulated salt batch 6 supernate, MST, and filter enhancers.

  18. Molecular dynamics simulation of sodium aluminosilicate glass structures and glass surface-water reactions using the reactive force field (ReaxFF)

    Science.gov (United States)

    Dongol, R.; Wang, L.; Cormack, A. N.; Sundaram, S. K.

    2018-05-01

    Reactive potentials are increasingly used to study the properties of glasses and glass water reactions in a reactive molecular dynamics (MD) framework. In this study, we have simulated a ternary sodium aluminosilicate glass and investigated the initial stages of the glass surface-water reactions at 300 K using reactive force field (ReaxFF). On comparison of the simulated glass structures generated using ReaxFF and classical Buckingham potentials, our results show that the atomic density profiles calculated for the surface glass structures indicate a bond-angle distribution dependency. The atomic density profiles also show higher concentrations of non-bridging oxygens (NBOs) and sodium ions at the glass surface. Additionally, we present our results of formation of silanol species and the diffusion of water molecules at the glass surface using ReaxFF.

  19. Rotationally invariant correlation filtering

    International Nuclear Information System (INIS)

    Schils, G.F.; Sweeney, D.W.

    1985-01-01

    A method is presented for analyzing and designing optical correlation filters that have tailored rotational invariance properties. The concept of a correlation of an image with a rotation of itself is introduced. A unified theory of rotation-invariant filtering is then formulated. The unified approach describes matched filters (with no rotation invariance) and circular-harmonic filters (with full rotation invariance) as special cases. The continuum of intermediate cases is described in terms of a cyclic convolution operation over angle. The angular filtering approach allows an exact choice for the continuous trade-off between loss of the correlation energy (or specificity regarding the image) and the amount of rotational invariance desired

  20. 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.

  1. Retina-Inspired Filter.

    Science.gov (United States)

    Doutsi, Effrosyni; Fillatre, Lionel; Antonini, Marc; Gaulmin, Julien

    2018-07-01

    This paper introduces a novel filter, which is inspired by the human retina. The human retina consists of three different layers: the Outer Plexiform Layer (OPL), the inner plexiform layer, and the ganglionic layer. Our inspiration is the linear transform which takes place in the OPL and has been mathematically described by the neuroscientific model "virtual retina." This model is the cornerstone to derive the non-separable spatio-temporal OPL retina-inspired filter, briefly renamed retina-inspired filter, studied in this paper. This filter is connected to the dynamic behavior of the retina, which enables the retina to increase the sharpness of the visual stimulus during filtering before its transmission to the brain. We establish that this retina-inspired transform forms a group of spatio-temporal Weighted Difference of Gaussian (WDoG) filters when it is applied to a still image visible for a given time. We analyze the spatial frequency bandwidth of the retina-inspired filter with respect to time. It is shown that the WDoG spectrum varies from a lowpass filter to a bandpass filter. Therefore, while time increases, the retina-inspired filter enables to extract different kinds of information from the input image. Finally, we discuss the benefits of using the retina-inspired filter in image processing applications such as edge detection and compression.

  2. Study of different filters

    International Nuclear Information System (INIS)

    Cochinal, R.; Rouby, R.

    1959-01-01

    This note first contains a terminology related to filters and to their operation, and then proposes an overview of general characteristics of filters such as load loss with respect to gas rate, efficiency, and clogging with respect to filter pollution. It also indicates standard aerosols which are generally used, how they are dosed, and how efficiency is determined with a standard aerosol. Then, after a presentation of the filtration principle, this note reports the study of several filters: glass wool, filter papers provided by different companies, Teflon foam, English filters, Teflon wool, sintered Teflonite, quartz wool, polyvinyl chloride foam, synthetic filter, sintered bronze. The third part reports the study of some aerosol and dust separators

  3. Changing ventilation filters

    International Nuclear Information System (INIS)

    Hackney, S.

    1980-01-01

    A filter changing unit has a door which interlocks with the door of a filter chamber so as to prevent contamination of the outer surfaces of the doors by radioactive material collected on the filter element and a movable support which enables a filter chamber thereonto to be stored within the unit in such a way that the doors of the unit and the filter chamber can be replaced. The door pivots and interlocks with another door by means of a bolt, a seal around the periphery lip of the first door engages the periphery of the second door to seal the gap. A support pivots into a lower filter element storage position. Inspection windows and glove ports are provided. The unit is releasably connected to the filter chamber by bolts engaging in a flange provided around an opening. (author)

  4. Balanced microwave filters

    CERN Document Server

    Hong, Jiasheng; Medina, Francisco; Martiacuten, Ferran

    2018-01-01

    This book presents and discusses strategies for the design and implementation of common-mode suppressed balanced microwave filters, including, narrowband, wideband, and ultra-wideband filters This book examines differential-mode, or balanced, microwave filters by discussing several implementations of practical realizations of these passive components. Topics covered include selective mode suppression, designs based on distributed and semi-lumped approaches, multilayer technologies, defect ground structures, coupled resonators, metamaterials, interference techniques, and substrate integrated waveguides, among others. Divided into five parts, Balanced Microwave Filters begins with an introduction that presents the fundamentals of balanced lines, circuits, and networks. Part 2 covers balanced transmission lines with common-mode noise suppression, including several types of common-mode filters and the application of such filters to enhance common-mode suppression in balanced bandpass filters. Next, Part 3 exa...

  5. [18F]F15599, a novel 5-HT1A receptor agonist, as a radioligand for PET neuroimaging

    International Nuclear Information System (INIS)

    Lemoine, Laetitia; Verdurand, Mathieu; Vacher, Bernard; Blanc, Elodie; Newman-Tancredi, Adrian; Le Bars, Didier; Zimmer, Luc

    2010-01-01

    The serotonin-1A (5-HT 1A ) receptor is implicated in the pathophysiology of major neuropsychiatric disorders. Thus, the functional imaging of 5-HT 1A receptors by positron emission tomography (PET) may contribute to the understanding of its role in those pathologies and their therapeutics. These receptors exist in high- and low-affinity states and it is proposed that agonists bind preferentially to the high-affinity state of the receptor and therefore could provide a measure of the functional 5-HT 1A receptors. Since all clinical PET 5-HT 1A radiopharmaceuticals are antagonists, it is of great interest to develop a 18 F labelled agonist. F15599 (3-chloro-4-fluorophenyl-(4-fluoro-4{ [(5-methyl-pyrimidin-2-ylmethyl)-amino]-methyl}-piperidin-1-yl)-methanone) is a novel ligand with high affinity and selectivity for 5-HT 1A receptors and is currently tested as an antidepressant. In pharmacological tests in rat, it exhibits preferential agonist activity at post-synaptic 5-HT 1A receptors in cortical brain regions. Here, its nitro-precursor was synthesised and radiolabelled via a fluoronucleophilic substitution. Radiopharmacological evaluations included in vitro and ex vivo autoradiography in rat brain and PET scans on rats and cats. Results were compared with simultaneous studies using [ 18 F]MPPF, a validated 5-HT 1A antagonist radiopharmaceutical. The chemical and radiochemical purities of [ 18 F]F15599 were >98%. In vitro [ 18 F ]F15599 binding was consistent with the known 5-HT 1A receptors distribution (hippocampus, dorsal raphe nucleus, and notably cortical areas) and addition of Gpp(NH)p inhibited [ 18 F ]F15599 binding, consistent with a specific binding to G protein-coupled receptors. In vitro binding of [ 18 F]F15599 was blocked by WAY100635 and 8-OH-DPAT, respectively, prototypical 5-HT 1A antagonist and agonist. The ex vivo and in vivo studies demonstrated that the radiotracer readily entered the rat and the cat brain and generated few brain radioactive

  6. Operations and maintenance manual for the temporary septic holding tank at the 300-FF-1 Remedial Action Support Facility

    International Nuclear Information System (INIS)

    Gilkeson, D.E.; Jackson, G.J.

    1997-02-01

    This document provides detailed information regarding the operations and maintenance of the septic holding tank system at the 300-FF-1 Remedial Action Support Facility, located in the 300 Area. This document includes the type and frequency of requirement maintenance, failure response procedures, and reporting requirements. Sanitary wastewater and raw sewage will enter the holding tank via a sloped 102 mm polyvinyl chloride (PVC) line from the office trailers. The septic holding tank will be emptied, as required, by system demands. During normal usage, it is estimated that the tank will require pumping every 3 working days. Approximately 834 gallons of sanitary wastewater and raw sewage will be disposed of into the septic system during this time

  7. Field evaluation of prototype electrofibrous filters

    International Nuclear Information System (INIS)

    Kuhl, W.D.; Bergman, W.; Biermann, A.H.; Lum, B.Y.

    1982-01-01

    New prototype electrofibrous filters were designed, built and evaluated in laboratory tests and in field installations. Two prototypes were designed for use in nuclear ventilation ducts as prefilters to HEPA filters. One prototype is designed to be a permanent component of the ventilation system while the other is a disposable unit. The disposable electrofibrous prefilter was installed in the exhaust stream of a glove box in which barrels of uranium turnings are burned. Preliminary tests show the disposal prefilter is effectively prolonging the HEPA filter life. An earlier prototype of the rolling prefilter was upgraded to meet the increased requirements for installation in a nuclear facility. This upgraded prototype was evaluated in the fire test facility at LLNL and shown to be effective in protecting HEPA filters from plugging under the most severe smoke conditions. The last prototype described in this report is a recirculating air filter. After demonstrating a high performance in laboratory tests the unit was shipped to Savannah River where it is awaiting installation in a Pu fuel fabrication facility. An analysis of the particulate problem in Savannah River indicates that four recirculating air filter will save $172,000 per year in maintenance costs

  8. Nuclear target foil fabrication for the Romano Event

    International Nuclear Information System (INIS)

    Weed, J.W.; Romo, J.G. Jr.; Griggs, G.E.

    1984-01-01

    The Vacuum Processes Lab, of LLNL's M.E. Dept. - Material Fabrication Division, was requested to provide 250 coated Parylene target foils for a nuclear physics experiment titled the ROMANO Event. Due to the developmental nature of some of the fabrication procedures, approximately 400 coated foils were produced to satisfy the event's needs. The foils were used in the experiment as subkilovolt x-ray, narrow band pass filters, and wide band ultraviolet filters. This paper is divided into three sections describing: (1) nuclear target foil fabrication, (2) Parylene substrate preparation and production, and (3) foil and substrate inspections

  9. Field test of radioactive high efficiency filter and filter exchange techniques of fuel cycle examination facility

    International Nuclear Information System (INIS)

    Hwang, Yong Hwa; Lee, Hyung Kwon; Chun, Young Bum; Park, Dae Gyu; Ahn, Sang Bok; Chu, Yong Sun; Kim, Eun Ka.

    1997-12-01

    The development of high efficiency filter was started to protect human beings from the contamination of radioactive particles, toxic gases and bacillus, and its gradual performance increment led to the fabrication of Ultra Low Penetration Air Filter (ULPA) today. The application field of ULPA has been spread not only to the air conditioning of nuclear power facilities, semiconductor industries, life science, optics, medical care and general facilities but also to the core of ultra-precision facilities. Periodic performance test on the filters is essential to extend its life-time through effective maintenance. Especially, the bank test on HEPA filter of nuclear facilities handling radioactive materials is required for environmental safety. Nowadays, the bank test technology has been reached to the utilization of a minimized portable detecting instruments and the evaluation techniques can provide high confidence in the area of particle distribution and leakage test efficiency. (author). 16 refs., 13 tabs., 14 figs

  10. FF-EMU: a radiation tolerant ASIC for the distribution of timing, trigger and control signals in the CMS End-Cap Muon detector

    International Nuclear Information System (INIS)

    Campagnari, C; Costantino, N; Magazzù, G; Tongiani, Claudio

    2012-01-01

    A radiation tolerant integrated circuit for the distribution of clock, trigger and control signals in the Front-End electronics of the CMS End-Cap Muon detector has been developed in the IBM CMOS 130nm technology. The circuit houses transmitter and receiver interfaces to serial links implementing the FF-LYNX protocol that allows the integrated transmission of triggers and data frames with different latency constraints. Encoder and decoder modules associate signal transitions to FF-LYNX frames. The system and the ASIC architecture and behavior and the results of test and characterization of the ASIC prototypes will be presented.

  11. Tiina Lokk: "PÖFF võiks olla Eestile väga vinge maineprojekt" / Tiina Lokk ; intervjueerinud Anneli Sihvart

    Index Scriptorium Estoniae

    Lokk, Tiina, 1955-

    2010-01-01

    14. Tallinna Pimedate Ööde Filmifestival toimub 19.11.-5.12.2010. Festivali peakorraldaja Tiina Lokk festivalist, selle sümbolist, PÖFF-i tähendusest maailma filmifestivalide seas, festivalidest Lätis, Leedus ja Venemaal, PÖFF-i rahastamisest, Eesti filmiharidusest. Tutvustatakse mängufilme: Anusha Rizvi "Peepli Live (India, 2010), Jasmila Žbanić'i "Teel" (Bosnia ja Hertsegoviina- Austria- Saksamaa- Horvaatia, 2010), Marianna Kaat'i dokumentaalfilmi "Auk nr 8" (Eesti-Ukraina, 2010)

  12. An Ethology of Urban Fabric(s)

    DEFF Research Database (Denmark)

    Fritsch, Jonas; Thomsen, Bodil Marie Stavning

    2014-01-01

    The article explores a non-metaphorical understanding of urban fabric(s), shifting the attention from a bird’s eye perspective to the actual, textural manifestations of a variety of urban fabric(s) to be studied in their real, processual, ecological and ethological complexity within urban life. We...... effectuate this move by bringing into resonance a range of intersecting fields that all deal with urban fabric(s) in complementary ways (interaction design and urban design activism, fashion, cultural theory, philosophy, urban computing)....

  13. Compact Unequal Power Divider with Filtering Response

    Directory of Open Access Journals (Sweden)

    Wei-Qiang Pan

    2015-01-01

    Full Text Available We present a novel unequal power divider with bandpass responses. The proposed power divider consists of five resonators and a resistor. The power division ratio is controlled by altering the coupling strength among the resonators. The output ports have the characteristic impedance of 50 Ω and impedance transformers in classical Wilkinson power dividers are not required in this design. Use of resonators enables the filtering function of the power divider. Two transmission zeros are generated near the passband edges, resulting in quasielliptic bandpass responses. For validation, a 2 : 1 filtering power divider is implemented. The fabricated circuit size is 0.22 λg × 0.08 λg, featuring compact size for unequal filtering power dividers, which is suitable for the feeding networks of antenna arrays.

  14. Tunable Microwave Filter Design Using Thin-Film Ferroelectric Varactors

    Science.gov (United States)

    Haridasan, Vrinda

    rejection, and constant bandwidth is designed, simulated, fabricated and measured. The filters are fabricated using barium strontium titanate (BST) varactors. Electromagnetic simulations and measured results of the tunable two-pole ferroelectric filter are analyzed to explore the origins of high insertion loss in ferroelectric filters. The results indicate that the high-permittivity of the BST (a ferroelectric) not only makes the filters tunable and compact, but also increases the conductive loss of the ferroelectric-based tunable resonators which translates into high insertion loss in ferroelectric filters.

  15. Filter material charging apparatus for filter assembly for radioactive contaminants

    International Nuclear Information System (INIS)

    Goldsmith, J.M.; O'Nan, A. Jr.

    1977-01-01

    A filter charging apparatus for a filter assembly is described. The filter assembly includes a housing with at least one filter bed therein and the filter charging apparatus for adding filter material to the filter assembly includes a tank with an opening therein, the tank opening being disposed in flow communication with opposed first and second conduit means, the first conduit means being in flow communication with the filter assembly housing and the second conduit means being in flow communication with a blower means. Upon activation of the blower means, the blower means pneumatically conveys the filter material from the tank to the filter housing

  16. A MEMS coupled resonator for frequency filtering in air

    KAUST Repository

    Ilyas, Saad

    2018-02-03

    We present design, fabrication, and characterization of a mechanically coupled MEMS H resonator capable of performing simultaneous mechanical amplification and filtering in air. The device comprises of two doubly clamped polyimide microbeams joined through the middle by a coupling beam of the same size. The resonator is fabricated via a multi-layer surface micromachining process. A special fabrication process and device design is employed to enable operation in air and to achieve mechanical amplification of the output response. Moreover, mixed-frequency excitation is used to demonstrate a tunable wide band filter for low frequency applications. It is demonstrated that through the multi-source harmonic excitation and the operation in air, an improved band-pass filter with flat response and minimal ripples can be achieved.

  17. A 15-pole high temperature superconductor filter for radar applications

    Science.gov (United States)

    Yu, Xiao; Xi, Weibin; Wu, Songtao

    2018-06-01

    This paper presents a compact and high first harmonic frequency resonator. The characteristics of this resonator are theoretically analyzed. A highly selective 15-pole Chebyshev high temperature superconducting ultra-high frequency narrowband filter for radar applications was fabricated by using this resonator. The filter has a center frequency of 495 MHz and a fractional bandwidth of 1%. The first harmonic frequency is more than 3.3 times the fundamental frequency. The measured filter shows excellent selectivity, better than 85 dB/1 MHz skirt slopes, and more than 85 dB of rejection at 497.5 MHz from the band edge. The filter was fabricated on a 2 inch YBCO thin film with a 0.5 mm thick MgO substrate. The experimental results are consistent with the simulations.

  18. Concentric Split Flow Filter

    Science.gov (United States)

    Stapleton, Thomas J. (Inventor)

    2015-01-01

    A concentric split flow filter may be configured to remove odor and/or bacteria from pumped air used to collect urine and fecal waste products. For instance, filter may be designed to effectively fill the volume that was previously considered wasted surrounding the transport tube of a waste management system. The concentric split flow filter may be configured to split the air flow, with substantially half of the air flow to be treated traveling through a first bed of filter media and substantially the other half of the air flow to be treated traveling through the second bed of filter media. This split flow design reduces the air velocity by 50%. In this way, the pressure drop of filter may be reduced by as much as a factor of 4 as compare to the conventional design.

  19. Power and Aging Characterization of Digital FIR Filters Architectures

    DEFF Research Database (Denmark)

    Calimera, Andrea; Liu, Wei; Macii, Enrico

    2012-01-01

    -variation, temperature and aging induced variations pose new challenges in the fabrication of the next generation of ICs. This work presents a detailed power and aging characterization of digital FIR filters in an industrial 45nm CMOS technology, and a design space exploration of different filter architectures...... with respect to throughput, area, power dissipation and aging. The exploration is intended to provide new design guidelines when considering aging of components in power/performance tradeoffs....

  20. Backflushable filter insert

    International Nuclear Information System (INIS)

    Keith, R.C.; Vandenberg, T.; Randolph, M.C.; Lewis, T.B.; Gillis, P.J. Jr.

    1988-01-01

    Filter elements are mounted on a tube plate beneath an accumulator chamber whose wall is extended by skirt and flange to form a closure for the top of pressure vessel. The accumulator chamber is annular around a central pipe which serves as the outlet for filtered water passing from the filter elements. The chamber contains filtered compressed air from supply. Periodically the filtration of water is stopped and vessel is drained. Then a valve is opened, allowing the accumulated air to flow from chamber up a pipe and down pipe, pushing the filtered water from pipe back through the filter elements to clean them. The accumulator chamber is so proportioned, relative to the volume of the system communicating therewith during backflushing, that the equilibrium pressure during backflushing cannot exceed the pressure rating of the vessel. However a line monitors the pressure at the top of the vessel, and if it rises too far a bleed valve is automatically opened to depressurise the system. The chamber is intended to replace the lid of an existing vessel to convert a filter using filter aid to one using permanent filter elements. (author)

  1. Updating the OMERACT filter

    DEFF Research Database (Denmark)

    Wells, George; Beaton, Dorcas E; Tugwell, Peter

    2014-01-01

    The "Discrimination" part of the OMERACT Filter asks whether a measure discriminates between situations that are of interest. "Feasibility" in the OMERACT Filter encompasses the practical considerations of using an instrument, including its ease of use, time to complete, monetary costs......, and interpretability of the question(s) included in the instrument. Both the Discrimination and Reliability parts of the filter have been helpful but were agreed on primarily by consensus of OMERACT participants rather than through explicit evidence-based guidelines. In Filter 2.0 we wanted to improve this definition...

  2. Nanofiber Filters Eliminate Contaminants

    Science.gov (United States)

    2009-01-01

    With support from Phase I and II SBIR funding from Johnson Space Center, Argonide Corporation of Sanford, Florida tested and developed its proprietary nanofiber water filter media. Capable of removing more than 99.99 percent of dangerous particles like bacteria, viruses, and parasites, the media was incorporated into the company's commercial NanoCeram water filter, an inductee into the Space Foundation's Space Technology Hall of Fame. In addition to its drinking water filters, Argonide now produces large-scale nanofiber filters used as part of the reverse osmosis process for industrial water purification.

  3. Filters in nuclear facilities

    International Nuclear Information System (INIS)

    Berg, K.H.; Wilhelm, J.G.

    1985-01-01

    The topics of the nine papers given include the behavior of HEPA filters during exposure to air flows of high humidity as well as of high differential pressure, the development of steel-fiber filters suitable for extreme operating conditions, and the occurrence of various radioactive iodine species in the exhaust air from boiling water reactors. In an introductory presentation the German view of the performance requirements to be met by filters in nuclear facilities as well as the present status of filter quality assurance are discussed. (orig.) [de

  4. Washing method of filter

    International Nuclear Information System (INIS)

    Izumidani, Masakiyo; Tanno, Kazuo.

    1978-01-01

    Purpose: To enable automatic filter operation and facilitate back-washing operation by back-washing filters used in a bwr nuclear power plant utilizing an exhaust gas from a ventilator or air conditioner. Method: Exhaust gas from an exhaust pipe of an ventilator or air conditioner is pressurized in a compressor and then introduced in a back-washing gas tank. Then, the exhaust gas pressurized to a predetermined pressure is blown from the inside to the outside of a filter to thereby separate impurities collected on the filter elements and introduce them to a waste tank. (Furukawa, Y.)

  5. The Late Devonian Frasnian-Famennian (F/F) biotic crisis: Insights from δ13C carb, δ13C org and 87Sr / 86Sr isotopic systematics

    Science.gov (United States)

    Chen, Daizhao; Qing, Hairuo; Li, Renwei

    2005-06-01

    A severe biotic crisis occurred during the Late Devonian Frasnian-Famennian (F/F) transition (± 367 Myr). Here we present δ13C carb, δ13C org and 87Sr / 86Sr isotopic systematics, from identical samples of two sections across F/F boundary in South China, which directly demonstrate large and frequent climatic fluctuations (˜200 kyr) from warming to cooling during the F/F transition. These climate fluctuations are interpreted to have been induced initially by increased volcanic outgassing, and subsequent enhanced chemical weathering linked to the rapid expansion of vascular plants on land, which would have increased riverine delivery to oceans and primary bioproductivity, and subsequent burial of organic matter, thereby resulting in climate cooling. Such large and frequent climatic fluctuations, together with volcanic-induced increases in nutrient (e.g., biolimiting Fe), toxin (sulfide) and anoxic water supply, and subsequent enhanced riverine fluxes and microbial bloom, were likely responsible for the stepwise faunal demise of F/F biotic crisis.

  6. Further along the Road Less Traveled: AMBER ff15ipq, an Original Protein Force Field Built on a Self-Consistent Physical Model

    Science.gov (United States)

    2016-01-01

    We present the AMBER ff15ipq force field for proteins, the second-generation force field developed using the Implicitly Polarized Q (IPolQ) scheme for deriving implicitly polarized atomic charges in the presence of explicit solvent. The ff15ipq force field is a complete rederivation including more than 300 unique atomic charges, 900 unique torsion terms, 60 new angle parameters, and new atomic radii for polar hydrogens. The atomic charges were derived in the context of the SPC/Eb water model, which yields more-accurate rotational diffusion of proteins and enables direct calculation of nuclear magnetic resonance (NMR) relaxation parameters from molecular dynamics simulations. The atomic radii improve the accuracy of modeling salt bridge interactions relative to contemporary fixed-charge force fields, rectifying a limitation of ff14ipq that resulted from its use of pair-specific Lennard-Jones radii. In addition, ff15ipq reproduces penta-alanine J-coupling constants exceptionally well, gives reasonable agreement with NMR relaxation rates, and maintains the expected conformational propensities of structured proteins/peptides, as well as disordered peptides—all on the microsecond (μs) time scale, which is a critical regime for drug design applications. These encouraging results demonstrate the power and robustness of our automated methods for deriving new force fields. All parameters described here and the mdgx program used to fit them are included in the AmberTools16 distribution. PMID:27399642

  7. Digital fundus image grading with the non-mydriatic Visucam(PRO NM) versus the FF450(plus) camera in diabetic retinopathy.

    Science.gov (United States)

    Neubauer, Aljoscha S; Rothschuh, Antje; Ulbig, Michael W; Blum, Marcus

    2008-03-01

    Grading diabetic retinopathy in clinical trials is frequently based on 7-field stereo photography of the fundus in diagnostic mydriasis. In terms of image quality, the FF450(plus) camera (Carl Zeiss Meditec AG, Jena, Germany) defines a high-quality reference. The aim of the study was to investigate if the fully digital fundus camera Visucam(PRO NM) could serve as an alternative in clinical trials requiring 7-field stereo photography. A total of 128 eyes of diabetes patients were enrolled in the randomized, controlled, prospective trial. Seven-field stereo photography was performed with the Visucam(PRO NM) and the FF450(plus) camera, in random order, both in diagnostic mydriasis. The resulting 256 image sets from the two camera systems were graded for retinopathy levels and image quality (on a scale of 1-5); both were anonymized and blinded to the image source. On FF450(plus) stereoscopic imaging, 20% of the patients had no or mild diabetic retinopathy (ETDRS level cameras regarding retinopathy levels (kappa 0.87) and macular oedema (kappa 0.80). In diagnostic mydriasis the image quality of the Visucam was graded slightly as better than that of the FF450(plus) (2.20 versus 2.41; p camera for applications and clinical trials requiring 7-field stereo photography.

  8. Kalman-filtered compressive sensing for high resolution estimation of anthropogenic greenhouse gas emissions from sparse measurements.

    Energy Technology Data Exchange (ETDEWEB)

    Ray, Jaideep; Lee, Jina; Lefantzi, Sophia; Yadav, Vineet; Michalak, Anna M.; van Bloemen Waanders, Bart Gustaaf; McKenna, Sean Andrew

    2013-09-01

    The estimation of fossil-fuel CO2 emissions (ffCO2) from limited ground-based and satellite measurements of CO2 concentrations will form a key component of the monitoring of treaties aimed at the abatement of greenhouse gas emissions. The limited nature of the measured data leads to a severely-underdetermined estimation problem. If the estimation is performed at fine spatial resolutions, it can also be computationally expensive. In order to enable such estimations, advances are needed in the spatial representation of ffCO2 emissions, scalable inversion algorithms and the identification of observables to measure. To that end, we investigate parsimonious spatial parameterizations of ffCO2 emissions which can be used in atmospheric inversions. We devise and test three random field models, based on wavelets, Gaussian kernels and covariance structures derived from easily-observed proxies of human activity. In doing so, we constructed a novel inversion algorithm, based on compressive sensing and sparse reconstruction, to perform the estimation. We also address scalable ensemble Kalman filters as an inversion mechanism and quantify the impact of Gaussian assumptions inherent in them. We find that the assumption does not impact the estimates of mean ffCO2 source strengths appreciably, but a comparison with Markov chain Monte Carlo estimates show significant differences in the variance of the source strengths. Finally, we study if the very different spatial natures of biogenic and ffCO2 emissions can be used to estimate them, in a disaggregated fashion, solely from CO2 concentration measurements, without extra information from products of incomplete combustion e.g., CO. We find that this is possible during the winter months, though the errors can be as large as 50%.

  9. Fabrication and Prototyping Lab

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The Fabrication and Prototyping Lab for composite structures provides a wide variety of fabrication capabilities critical to enabling hands-on research and...

  10. The impact of flattening-filter-free beam technology on 3D conformal RT

    Science.gov (United States)

    2013-01-01

    Background The removal of the flattening filter (FF) leads to non-uniform fluence distribution with a considerable increase in dose rate. It is possible to adapt FFF beams (flattening-filter-free) in 3D conformal radiation therapy (3D CRT) by using field in field techniques (FiF). The aim of this retrospective study is to clarify whether the quality of 3D CRT plans is influenced by the use of FFF beams. Method This study includes a total of 52 CT studies of RT locations that occur frequently in clinical practice. Dose volume targets were provided for the PTV of breast (n=13), neurocranium (n=11), lung (n=7), bone metastasis (n=10) and prostate (n=11) in line with ICRU report 50/62. 3D CRT planning was carried out using FiF methods. Two clinically utilized photon energies are used for a Siemens ARTISTE linear accelerator in FFF mode at 7MVFFF and 11MVFFF as well as in FF mode at 6MVFF and 10MVFF. The plan quality in relation to the PTV coverage, OAR (organs at risk) and low dose burden as well as the 2D dosimetric verification is compared with FF plans. Results No significant differences were found between FFF and FF plans in the mean dose for the PTV of breast, lung, spine metastasis and prostate. The low dose parameters V5Gy and V10Gy display significant differences for FFF and FF plans in some subgroups. The DVH analysis of the OAR revealed some significant differences. Significantly more fields (1.9 – 4.5) were necessary in the use of FFF beams for each location (p<0.0001) in order to achieve PTV coverage. All the tested groups displayed significant increases (1.3 – 2.2 times) in the average number of necessary MU with the use of FFF beams (p<0.001). Conclusions This study has shown that the exclusive use of a linear accelerator in FFF mode is feasible in 3D CRT. It was possible to realize RT plans in comparable quality in typical cases of clinical radiotherapy. The 2D dosimetric validation of the modulated fields verified the dose calculation and thus the

  11. TESTING OF THE SECOND GENERATION SPINTEK ROTARY FILTER -11357

    Energy Technology Data Exchange (ETDEWEB)

    Herman, D.; Poirier, M.; Fowley, M.; Keefer, M.; Huff, T.

    2011-02-02

    The SpinTek rotary microfilter has been developed under the Department of Energy (DOE) Office of Environmental Management (EM) for the purpose of deployment in radioactive service in the DOE complex. The unit that was fabricated and tested is the second generation of the filter that incorporates recommended improvements from previous testing. The completion of this test satisfied a key milestone for the EM technology development program and technology readiness for deployment by Savannah River Remediation in the Small Column Ion Exchange and Sludge Washing processes at the Savannah River Site (SRS). The Savannah River National Laboratory (SRNL) contracted SpinTek Filtration to fabricate a full scale 25 disk rotary filter and perform a 1000 hour endurance test with a simulated SRS sludge. Over 1500 hours of operation have been completed with the filter. SpinTek Filtration fabricated a prototypic 25 disk rotary filter including updates to manufacturing tolerances, an updated design to the rotary joint, improved cooling to the bottom journal, decreases in disk and filter shaft hydraulic resistances. The filter disks were fabricated with 0.5 {micro} pore size, sintered-metal filter media manufactured by Pall Corporation (M050). After fabrication was complete, the filter passed acceptance tests demonstrating rejection of solids and clean water flux with a 50% improvement over the previous filters. Once the acceptance test was complete, a 1000 hour endurance test was initiated simulating a sludge washing process. The test used a simulated SRS Sludge Batch 6 recipe. The insoluble solids started at 5 wt% and were raised to 10 and 15 wt% insoluble solids to simulate the concentration of a large volume tank. The filter system was automated and set up for 24 hour unattended operation. To facilitate this, process control logic was written to operate the filter. During the development it was demonstrated that the method of starting and stopping the filter can affect the build

  12. Potential of simple filters to improve microbial quality of irrigation water used in urban vegetable farming in Ghana

    DEFF Research Database (Denmark)

    Keraita, Bernard; Drechsel, Pay; Konradsen, Flemming

    2008-01-01

    . As part of a larger study on possible interventions for health risk reduction, the potential of simple interventions was explored. Column slow sand filters with three levels of sand depths (0.5 m, 0.75 m and 1 m) and fabric filters made of nylon, cotton and netting were assessed. More than 600 water...... samples were analyzed for helminth eggs and thermotolerant coliforms. Flow rates were also measured. From slow sand filters, 71-96% of helminths and 2 log units (from 7 to 5 log units) of thermotolerant coliforms were removed. Sand depths had no significant influence in the removal. Lower removal rates...... were achieved by fabric filters, with an average removal of 12-62% for helminth eggs and 1 log unit for thermotolerant coliforms. Nylon filters had higher removal rates especially for helminth eggs (58%). Average flow rates for sand filters were 3 m per day and fabric filters had steady flows of about...

  13. Treatment of breast cancer with simultaneous integrated boost in hybrid plan technique. Influence of flattening filter-free beams

    Energy Technology Data Exchange (ETDEWEB)

    Bahrainy, Marzieh; Kretschmer, Matthias; Joest, Vincent; Kasch, Astrid; Wuerschmidt, Florian; Dahle, Joerg; Lorenzen, Joern [Radiologische Allianz, Hamburg (Germany)

    2016-05-15

    The present study compares in silico treatment plans using hybrid plan technique during hypofractionated radiation of mammary carcinoma with simultaneous integrated boost (SIB). The influence of 6 MV photon radiation in flattening filter free (FFF) mode against the clinical standard flattening filter (FF) mode is to be examined. RT planning took place with FF and FFF radiation plans for 10 left-sided breast cancer patients. Hybrid plans were realised with two tangential IMRT fields and one VMAT field. The dose prescription was in line with the guidelines in the ARO-2010-01 study. The dosimetric verification took place with a manufacturer-independent measurement system. Required dose prescriptions for the planning target volumes (PTV) were achieved for both groups. The average dose values of the ipsi- and contralateral lung and the heart did not differ significantly. The overall average incidental dose to the left anterior descending artery (LAD) of 8.24 ± 3.9 Gy in the FFF group and 9.05 ± 3.7 Gy in the FF group (p < 0.05) were found. The dosimetric verifications corresponded to the clinical requirements. FFF-based RT plans reduced the average treatment time by 17 s/fraction. In comparison to the FF-based hybrid plan technique the FFF mode allows further reduction of the average LAD dose for comparable target volume coverage without adverse low-dose exposure of contralateral structures. The combination of hybrid plan technique and 6 MV photon radiation in the FFF mode is suitable for use with hypofractionated dose schemes. The increased dose rate allows a substantial reduction of treatment time and thus beneficial application of the deep inspiration breath hold technique. (orig.) [German] Vergleich der ''In-silico''-Bestrahlungsplaene der klinisch etablierten Hybridplan-Technik bei hypofraktionierter Bestrahlung des Mammakarzinoms mit simultan integriertem Boost (SIB). Untersucht wird der Einfluss von 6MV-Photonenstrahlung im Flattening-Filter

  14. Multilevel ensemble Kalman filter

    KAUST Repository

    Chernov, Alexey; Hoel, Haakon; Law, Kody; Nobile, Fabio; Tempone, Raul

    2016-01-01

    This work embeds a multilevel Monte Carlo (MLMC) sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF). In terms of computational cost vs. approximation error the asymptotic performance of the multilevel ensemble Kalman filter (MLEnKF) is superior to the EnKF s.

  15. Neutron Beam Filters

    International Nuclear Information System (INIS)

    Adib, M.

    2011-01-01

    The purpose of filters is to transmit neutrons with selected energy, while remove unwanted ones from the incident neutron beam. This reduces the background, and the number of spurious. The types of commonly used now-a-day neutron filters and their properties are discussed in the present work. There are three major types of neutron filters. The first type is filter of selective thermal neutron. It transmits the main reflected neutrons from a crystal monochromate, while reject the higher order contaminations accompanying the main one. Beams coming from the moderator always contain unwanted radiation like fast neutrons and gamma-rays which contribute to experimental background and to the biological hazard potential. Such filter type is called filter of whole thermal neutron spectrum. The third filter type is it transmits neutrons with energies in the resonance energy range (En . 1 KeV). The main idea of such neutron filter technique is the use of large quantities of a certain material which have the deep interference minima in its total neutron cross-section. By transmitting reactor neutrons through bulk layer of such material, one can obtain the quasimonochromatic neutron lines instead of white reactor spectrum.

  16. Side loading filter apparatus

    International Nuclear Information System (INIS)

    Reynolds, K.E.

    1981-01-01

    A side loading filter chamber for use with radioactive gases is described. The equipment incorporates an inexpensive, manually operated, mechanism for aligning filter units with a number of laterally spaced wall openings and for removing the units from the chamber. (U.K.)

  17. Multilevel ensemble Kalman filter

    KAUST Repository

    Chernov, Alexey

    2016-01-06

    This work embeds a multilevel Monte Carlo (MLMC) sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF). In terms of computational cost vs. approximation error the asymptotic performance of the multilevel ensemble Kalman filter (MLEnKF) is superior to the EnKF s.

  18. Multi-tap complex-coefficient incoherent microwave photonic filters based on optical single-sideband modulation and narrow band optical filtering.

    Science.gov (United States)

    Sagues, Mikel; García Olcina, Raimundo; Loayssa, Alayn; Sales, Salvador; Capmany, José

    2008-01-07

    We propose a novel scheme to implement tunable multi-tap complex coefficient filters based on optical single sideband modulation and narrow band optical filtering. A four tap filter is experimentally demonstrated to highlight the enhanced tuning performance provided by complex coefficients. Optical processing is performed by the use of a cascade of four phase-shifted fiber Bragg gratings specifically fabricated for this purpose.

  19. Experimental use of iteratively designed rotation invariant correlation filters

    International Nuclear Information System (INIS)

    Sweeney, D.W.; Ochoa, E.; Schils, G.F.

    1987-01-01

    Iteratively designed filters are incorporated into an optical correlator for position, rotation, and intensity invariant recognition of target images. The filters exhibit excellent discrimination because they are designed to contain full information about the target image. Numerical simulations and experiments demonstrate detection of targets that are corrupted with random noise (SNR≅0.5) and also partially obscured by other objects. The complex valued filters are encoded in a computer generated hologram and fabricated directly using an electron-beam system. Experimental results using a liquid crystal spatial light modulator for real-time input show excellent agreement with analytical and numerical computations

  20. Filtering and prediction

    CERN Document Server

    Fristedt, B; Krylov, N

    2007-01-01

    Filtering and prediction is about observing moving objects when the observations are corrupted by random errors. The main focus is then on filtering out the errors and extracting from the observations the most precise information about the object, which itself may or may not be moving in a somewhat random fashion. Next comes the prediction step where, using information about the past behavior of the object, one tries to predict its future path. The first three chapters of the book deal with discrete probability spaces, random variables, conditioning, Markov chains, and filtering of discrete Markov chains. The next three chapters deal with the more sophisticated notions of conditioning in nondiscrete situations, filtering of continuous-space Markov chains, and of Wiener process. Filtering and prediction of stationary sequences is discussed in the last two chapters. The authors believe that they have succeeded in presenting necessary ideas in an elementary manner without sacrificing the rigor too much. Such rig...

  1. Filter cake breaker systems

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Marcelo H.F. [Poland Quimica Ltda., Duque de Caxias, RJ (Brazil)

    2004-07-01

    Drilling fluids filter cakes are based on a combination of properly graded dispersed particles and polysaccharide polymers. High efficiency filter cakes are formed by these combination , and their formation on wellbore walls during the drilling process has, among other roles, the task of protecting the formation from instantaneous or accumulative invasion of drilling fluid filtrate, granting stability to well and production zones. Filter cake minimizes contact between drilling fluid filtrate and water, hydrocarbons and clay existent in formations. The uniform removal of the filter cake from the entire interval is a critical factor of the completion process. The main methods used to breaking filter cake are classified into two groups, external or internal, according to their removal mechanism. The aim of this work is the presentation of these mechanisms as well their efficiency. (author)

  2. Sub-micron filter

    Science.gov (United States)

    Tepper, Frederick [Sanford, FL; Kaledin, Leonid [Port Orange, FL

    2009-10-13

    Aluminum hydroxide fibers approximately 2 nanometers in diameter and with surface areas ranging from 200 to 650 m.sup.2/g have been found to be highly electropositive. When dispersed in water they are able to attach to and retain electronegative particles. When combined into a composite filter with other fibers or particles they can filter bacteria and nano size particulates such as viruses and colloidal particles at high flux through the filter. Such filters can be used for purification and sterilization of water, biological, medical and pharmaceutical fluids, and as a collector/concentrator for detection and assay of microbes and viruses. The alumina fibers are also capable of filtering sub-micron inorganic and metallic particles to produce ultra pure water. The fibers are suitable as a substrate for growth of cells. Macromolecules such as proteins may be separated from each other based on their electronegative charges.

  3. Monolithic Integrated Ceramic Waveguide Filters

    OpenAIRE

    Hunter, IC; Sandhu, MY

    2014-01-01

    Design techniques for a new class of integrated monolithic high permittivity ceramic waveguide filters are presented. These filters enable a size reduction of 50% compared to air-filled TEM filters with the same unloaded Q-Factor. Designs for both chebyshev and asymmetric generalized chebyshev filter are presented, with experimental results for an 1800 MHz chebyshev filter showing excellent agreement with theory.

  4. Liquid Adsorption of Organic Compounds on Hematite α-Fe2O3 Using ReaxFF.

    Science.gov (United States)

    Chia, Chung-Lim; Avendaño, Carlos; Siperstein, Flor R; Filip, Sorin

    2017-10-24

    ReaxFF-based molecular dynamics simulations are used in this work to study the effect of the polarity of adsorbed molecules in the liquid phase on the structure and polarization of hematite (α-Fe 2 O 3 ). We compared the adsorption of organic molecules with different polarities on a rigid hematite surface and on a flexible and polarizable surface. We show that the displacements of surface atoms and surface polarization in a flexible hematite model are proportional to the adsorbed molecule's polarity. The increase in electrostatic interactions resulting from charge transfer in the outermost solid atoms in a flexible hematite model results in better-defined adsorbed layers that are less ordered than those obtained assuming a rigid solid. These results suggest that care must be taken when parametrizing empirical transferable force fields because the calculated charges on a solid slab in vacuum may not be representative of a real system, especially when the solid is in contact with a polar liquid.

  5. Micromechanism of oxygen transport during initial stage oxidation in Si(100) surface: A ReaxFF molecular dynamics simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yu, E-mail: yu.sun@xjtu.edu.cn [State Key Laboratory for Manufacturing Systems Engineering, School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Institute for Computational Mechanics and Its Applications, Northwestern Polytechnical University, Xi’an 710072 (China); Liu, Yilun [State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Chen, Xuefeng; Zhai, Zhi [State Key Laboratory for Manufacturing Systems Engineering, School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Xu, Fei [Institute for Computational Mechanics and Its Applications, Northwestern Polytechnical University, Xi’an 710072 (China); Liu, Yijun [Institute for Computational Mechanics and Its Applications, Northwestern Polytechnical University, Xi’an 710072 (China); Mechanical Engineering, University of Cincinnati, Cincinnati, OH 45221-0072 (United States)

    2017-06-01

    Highlights: • A competition mechanism between thermal actuation and compressive stress blocking was found for the oxygen transport. • At low temperature, a compressive stress was generated in the oxide layer which blocked oxygen transport into the deeper region. • O atoms gained larger possibility to go deeper inward as temperature increase. • The related film quality was well explained by the competition mechanism. - Abstract: The early stage oxidation in Si(100) surface has been investigated in this work by a reactive force field molecular dynamics (ReaxFF MD) simulation, manifesting that the oxygen transport acted as a dominant issue for initial oxidation process. Due to the oxidation, a compressive stress was generated in the oxide layer which blocked the oxygen transport perpendicular to the Si(100) surface and further prevented oxidation in the deeper layer. In contrast, thermal actuation was beneficial to the oxygen transport into deeper layer as temperature increases. Therefore, a competition mechanism was found for the oxygen transport during early stage oxidation in Si(100) surface. At room temperature, the oxygen transport was governed by the blocking effect of compressive stress, so a better quality oxide film with more uniform interface and more stoichiometric oxide structure was obtained. Indeed, the mechanism presented in this work is also applicable for other self-limiting oxidation (e.g. metal oxidation) and is helpful for the design of high-performance electronic devices.

  6. Data compilation task report for the source investigation of the 300-FF-1 operable unit phase 1 remedial investigation

    International Nuclear Information System (INIS)

    Young, J.S.; Fruland, R.M.; Fruchter, J.S.

    1990-02-01

    This report provides additional information on facility and waste characteristics for the 300-FF-1 operable unit. The additional information gathered and reported includes meetings and on-site visits with current and past personnel having knowledge of operations in the operable unit, a more precise determination of the location of the Process Sewer lines and Retired Radioactive Liquid Waste Sewer, a better understanding of the phosphoric acid spill at the 340 Complex, and a search for engineering plans and environmental reports related to the operable unit. As a result of this data-gathering effort, recommendations for further investigation include characterization of the 307 Trenches to determine the origin of an underlying uranium plume in the groundwater, more extensive sampling of near-surface and dike sediments in the North and South Process Ponds to better define the extent of horizontal contamination, and detection of possible leaks in the abandoned Radioactive Waste Sewer by either electromagnetic induction or remote television camera inspection techniques. 16 refs., 4 figs., 5 tabs

  7. Micromechanism of oxygen transport during initial stage oxidation in Si(100) surface: A ReaxFF molecular dynamics simulation study

    International Nuclear Information System (INIS)

    Sun, Yu; Liu, Yilun; Chen, Xuefeng; Zhai, Zhi; Xu, Fei; Liu, Yijun

    2017-01-01

    Highlights: • A competition mechanism between thermal actuation and compressive stress blocking was found for the oxygen transport. • At low temperature, a compressive stress was generated in the oxide layer which blocked oxygen transport into the deeper region. • O atoms gained larger possibility to go deeper inward as temperature increase. • The related film quality was well explained by the competition mechanism. - Abstract: The early stage oxidation in Si(100) surface has been investigated in this work by a reactive force field molecular dynamics (ReaxFF MD) simulation, manifesting that the oxygen transport acted as a dominant issue for initial oxidation process. Due to the oxidation, a compressive stress was generated in the oxide layer which blocked the oxygen transport perpendicular to the Si(100) surface and further prevented oxidation in the deeper layer. In contrast, thermal actuation was beneficial to the oxygen transport into deeper layer as temperature increases. Therefore, a competition mechanism was found for the oxygen transport during early stage oxidation in Si(100) surface. At room temperature, the oxygen transport was governed by the blocking effect of compressive stress, so a better quality oxide film with more uniform interface and more stoichiometric oxide structure was obtained. Indeed, the mechanism presented in this work is also applicable for other self-limiting oxidation (e.g. metal oxidation) and is helpful for the design of high-performance electronic devices.

  8. Exploring the Abyss. The Financial Crisis of 2008 ff. as a Central Topic of Problem-Centered Social Science Education

    Directory of Open Access Journals (Sweden)

    Thorsten Hippe

    2010-07-01

    Full Text Available The financial crisis of 2008 ff. and financial crises in general should be a central topic of social science education because these crises are a recurrent and therefore structural feature of modern capitalism which has severe consequences for citizens’ quality of life. Hence, the citizenry should know how to prevent such developments which endanger its well-being in a massive way. Therefore, learners should understand the relationship between the quality of people’s everyday lives and those economic institutions and political decisions which have led to the current mess. They should be enabled to critically evaluate the current misregulation of the financial sector and the economy in order to identify possible policy measures to prevent or at least to mitigate future crises. By educating (young citizens in this way, the (future general public can – as a necessary counterweight to the lobbyism of the finance industry – exert more prudent political pressure which gives politicians a greater incentive to regulate the financial sector and the economy in a manner which is beneficial for the vast majority of the people instead of for a small elite. Two core concepts of the social sciences can be used to make the roots of the seemingly complex topic more understandable for learners: liability and inequality.

  9. Interplay between dynamic screened f-f interaction and sk·sf interaction in Ce systems

    International Nuclear Information System (INIS)

    Lopez-Aguilar, F.; Costa-Quintana, J.; Sanchez-Lopez, M.M.

    1997-01-01

    Two complementary analyses for the electronic structure of Ce systems are given. The first is performed from the renormalized density of states (DOS) deduced from the interacting Green close-quote s functions. These Green close-quote s functions are obtained from a self-energy calculated from a multiband Hubbard Hamiltonian and using the random phase approximation to account for the dynamical f-f screened interactions. The resulting DOS presents agreements and discrepancies with the spectral data yielded by direct and inverse photoemission. The theoretical and experimental f widths next to the Fermi level imply f-electron masses that are in strong contradiction with those obtained from the heavy-fermion specific heat. We have carried out a second analysis that complements the first one, since it considers the spin-exchange between extended states and a spin-field that is completely excluded from the first calculation. By the marriage of the results obtained in the first calculation with those of the second analysis, we can relate the photoemission spectra and de Haas endash van Alphen masses with the measurements of the contribution of the low-energy quasiparticles to the specific heat and the magnetic susceptibility. copyright 1997 The American Physical Society

  10. Point-of-use water purification using clay pot water filters and copper ...

    African Journals Online (AJOL)

    2011-11-24

    Nov 24, 2011 ... clay pot water filters (CPWFs) were fabricated using terracotta clay and sawdust. The sawdust was .... developed by educational initiatives and non-governmental .... est filtration rate, it had the disadvantage of not being able to.

  11. Polymorphous computing fabric

    Science.gov (United States)

    Wolinski, Christophe Czeslaw [Los Alamos, NM; Gokhale, Maya B [Los Alamos, NM; McCabe, Kevin Peter [Los Alamos, NM

    2011-01-18

    Fabric-based computing systems and methods are disclosed. A fabric-based computing system can include a polymorphous computing fabric that can be customized on a per application basis and a host processor in communication with said polymorphous computing fabric. The polymorphous computing fabric includes a cellular architecture that can be highly parameterized to enable a customized synthesis of fabric instances for a variety of enhanced application performances thereof. A global memory concept can also be included that provides the host processor random access to all variables and instructions associated with the polymorphous computing fabric.

  12. Filter aids influence on pressure drop across a filtration system

    Science.gov (United States)

    Hajar, S.; Rashid, M.; Nurnadia, A.; Ammar, M. R.; Hasfalina, C. M.

    2017-06-01

    Filter aids is commonly used to reduce pressure drop across air filtration system as it helps to increase the efficiency of filtration of accumulated filter cake. Filtration velocity is one of the main parameters that affect the performance of filter aids material. In this study, a formulated filter aids consisting of PreKot™ and activated carbon mixture (designated as PrekotAC) was tested on PTFE filter media under various filtration velocities of 5, 6, and 8 m/min at a constant material loading of 0.2 mg/mm2. Results showed that pressure drop is highly influenced by filtration velocity where higher filtration velocity leads to a higher pressure drop across the filter cake. It was found that PrekotAC performed better in terms of reducing the pressure drop across the filter cake even at the highest filtration velocity. The diversity in different particle size distribution of non-uniform particle size in the formulated PrekotAC mixture presents a higher permeability causes a lower pressure drop across the accumulated filter cake. The finding suggests that PrekotAC is a promising filter aids material that helps reducing the pressure drop across fabric filtration system.

  13. Evaluation of Alternative Filter Media for the Rotary Microfilter

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, M. R.; Herman, D. T.; Bhave, R.

    2011-11-09

    The Savannah River Site is currently developing and testing several processes to treat high level radioactive liquid waste. Each of these processes has a solid-liquid separation process that limits its throughput. Savannah River National Laboratory researchers identified and tested the rotary microfilter as a technology to increase solid-liquid separation throughput. The authors believe the rotary microfilter throughput can be improved by using a better filter membrane. Previous testing showed that asymmetric filters composed of a ceramic membrane on top of a stainless steel support produced higher filter flux than 100% stainless steel symmetric filters in crossflow filter tests. Savannah River National Laboratory and Oak Ridge National Laboratory are working together to develop asymmetric ceramic ? stainless steel composite filters and asymmetric 100% stainless steel filters to improve the throughput of the rotary microfilter. The Oak Ridge National Laboratory Inorganic Membrane Group fabricated samples of alternative filter membranes. In addition, Savannah River National Laboratory obtained samples of filter membranes from Pall, Porvair, and SpinTek. They tested these samples in a static test cell with feed slurries containing monosodium titanate and simulated sludge.

  14. Evaluation of Alternative Filter Media for the Rotary Microfilter

    International Nuclear Information System (INIS)

    Poirier, M. R.; Herman, D. T.; Bhave, R.

    2011-01-01

    The Savannah River Site is currently developing and testing several processes to treat high level radioactive liquid waste. Each of these processes has a solid-liquid separation process that limits its throughput. Savannah River National Laboratory researchers identified and tested the rotary microfilter as a technology to increase solid-liquid separation throughput. The authors believe the rotary microfilter throughput can be improved by using a better filter membrane. Previous testing showed that asymmetric filters composed of a ceramic membrane on top of a stainless steel support produced higher filter flux than 100% stainless steel symmetric filters in crossflow filter tests. Savannah River National Laboratory and Oak Ridge National Laboratory are working together to develop asymmetric ceramic-stainless steel composite filters and asymmetric 100% stainless steel filters to improve the throughput of the rotary microfilter. The Oak Ridge National Laboratory Inorganic Membrane Group fabricated samples of alternative filter membranes. In addition, Savannah River National Laboratory obtained samples of filter membranes from Pall, Porvair, and SpinTek. They tested these samples in a static test cell with feed slurries containing monosodium titanate and simulated sludge

  15. Directly-deposited blocking filters for high-performance silicon x-ray detectors

    Science.gov (United States)

    Bautz, M.; Kissel, S.; Masterson, R.; Ryu, K.; Suntharalingam, V.

    2016-07-01

    Silicon X-ray detectors often require blocking filters to mitigate noise and out-of-band signal from UV and visible backgrounds. Such filters must be thin to minimize X-ray absorption, so direct deposition of filter material on the detector entrance surface is an attractive approach to fabrication of robust filters. On the other hand, the soft (E OD 6) care must be taken to prevent light from entering the sides and mounting surfaces of the detector. Our methods have been used to deposit filters on the detectors of the REXIS instrument scheduled to fly on OSIRIS-ReX later this year.

  16. DC-pass filter design with notch filters superposition for CPW rectenna at low power level

    Science.gov (United States)

    Rivière, J.; Douyère, A.; Alicalapa, F.; Luk, J.-D. Lan Sun

    2016-03-01

    In this paper the challenging coplanar waveguide direct current (DC) pass filter is designed, analysed, fabricated and measured. As the ground plane and the conductive line are etched on the same plane, this technology allows the connection of series and shunt elements to the active devices without via holes through the substrate. Indeed, this study presents the first step in the optimization of a complete rectenna in coplanar waveguide (CPW) technology: key element of a radio frequency (RF) energy harvesting system. The measurement of the proposed filter shows good performance in the rejection of F0=2.45 GHz and F1=4.9 GHz. Additionally, a harmonic balance (HB) simulation of the complete rectenna is performed and shows a maximum RF-to-DC conversion efficiency of 37% with the studied DC-pass filter for an input power of 10 µW at 2.45 GHz.

  17. Circuits and filters handbook

    CERN Document Server

    Chen, Wai-Kai

    2003-01-01

    A bestseller in its first edition, The Circuits and Filters Handbook has been thoroughly updated to provide the most current, most comprehensive information available in both the classical and emerging fields of circuits and filters, both analog and digital. This edition contains 29 new chapters, with significant additions in the areas of computer-aided design, circuit simulation, VLSI circuits, design automation, and active and digital filters. It will undoubtedly take its place as the engineer's first choice in looking for solutions to problems encountered in the design, analysis, and behavi

  18. EMI filter design

    CERN Document Server

    Ozenbaugh, Richard Lee

    2011-01-01

    With today's electrical and electronics systems requiring increased levels of performance and reliability, the design of robust EMI filters plays a critical role in EMC compliance. Using a mix of practical methods and theoretical analysis, EMI Filter Design, Third Edition presents both a hands-on and academic approach to the design of EMI filters and the selection of components values. The design approaches covered include matrix methods using table data and the use of Fourier analysis, Laplace transforms, and transfer function realization of LC structures. This edition has been fully revised

  19. Randomized Filtering Algorithms

    DEFF Research Database (Denmark)

    Katriel, Irit; Van Hentenryck, Pascal

    2008-01-01

    of AllDifferent and is generalization, the Global Cardinality Constraint. The first delayed filtering scheme is a Monte Carlo algorithm: its running time is superior, in the worst case, to that of enforcing are consistency after every domain event, while its filtering effectiveness is analyzed...... in the expected sense. The second scheme is a Las Vegas algorithm using filtering triggers: Its effectiveness is the same as enforcing are consistency after every domain event, while in the expected case it is faster by a factor of m/n, where n and m are, respectively, the number of nodes and edges...

  20. Corrosive environment tester for filter media

    International Nuclear Information System (INIS)

    Petit, G.S.; Weber, C.W.; Keinberger, C.A.; Rivers, R.D.

    1977-02-01

    Two continuous dynamic systems have been designed and fabricated for testing filter media in humid, corrosive environments--one for fluorine or fluoride exposures, and the other for nitrogen dioxide exposures. The tester using fluorine or fluoride atmospheres was constructed of nickel and the one using nitrogen dioxide was fabricated of stainless steel. Other corrosive gases could be used with the appropriate choice of system. For example, chlorine or hydrogen chloride could be used in the system fabricated of nickel, and sulfur dioxides or ammonia could be used in the stainless steel testing apparatus. Each tester is comprised of four equivalent dynamic systems designed for diluting a corrosive reagent with dry air, then with humidified air to provide a humid-corrosive environment for filter media testing. Auxiliary equipment includes a water injection system, corrosive reagent supply systems, and an automatic pressure differential (ΔP) monitoring and recording system. The testers are relatively maintenance-free and have operated continuously for periods as long as 96 h without requiring any attention, during total exposures of materials exceeding 600 h

  1. 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...

  2. Metalcasting: Filtering Molten Metal

    International Nuclear Information System (INIS)

    Lauren Poole; Lee Recca

    1999-01-01

    A more efficient method has been created to filter cast molten metal for impurities. Read about the resulting energy and money savings that can accrue to many different industries from the use of this exciting new technology

  3. Perspectives on Nonlinear Filtering

    KAUST Repository

    Law, Kody

    2015-01-01

    The solution to the problem of nonlinear filtering may be given either as an estimate of the signal (and ideally some measure of concentration), or as a full posterior distribution. Similarly, one may evaluate the fidelity of the filter either by its ability to track the signal or its proximity to the posterior filtering distribution. Hence, the field enjoys a lively symbiosis between probability and control theory, and there are plenty of applications which benefit from algorithmic advances, from signal processing, to econometrics, to large-scale ocean, atmosphere, and climate modeling. This talk will survey some recent theoretical results involving accurate signal tracking with noise-free (degenerate) dynamics in high-dimensions (infinite, in principle, but say d between 103 and 108 , depending on the size of your application and your computer), and high-fidelity approximations of the filtering distribution in low dimensions (say d between 1 and several 10s).

  4. HEPA air filter (image)

    Science.gov (United States)

    ... pet dander and other irritating allergens from the air. Along with other methods to reduce allergens, such ... controlling the amount of allergens circulating in the air. HEPA filters can be found in most air ...

  5. Updating the OMERACT filter

    DEFF Research Database (Denmark)

    Tugwell, Peter; Boers, Maarten; D'Agostino, Maria-Antonietta

    2014-01-01

    OBJECTIVE: The Outcome Measures in Rheumatology (OMERACT) Filter provides guidelines for the development and validation of outcome measures for use in clinical research. The "Truth" section of the OMERACT Filter requires that criteria be met to demonstrate that the outcome instrument meets...... the criteria for content, face, and construct validity. METHODS: Discussion groups critically reviewed a variety of ways in which case studies of current OMERACT Working Groups complied with the Truth component of the Filter and what issues remained to be resolved. RESULTS: The case studies showed...... that there is broad agreement on criteria for meeting the Truth criteria through demonstration of content, face, and construct validity; however, several issues were identified that the Filter Working Group will need to address. CONCLUSION: These issues will require resolution to reach consensus on how Truth...

  6. Updating the OMERACT filter

    DEFF Research Database (Denmark)

    Kirwan, John R; Boers, Maarten; Hewlett, Sarah

    2014-01-01

    OBJECTIVE: The Outcome Measures in Rheumatology (OMERACT) Filter provides guidelines for the development and validation of outcome measures for use in clinical research. The "Truth" section of the OMERACT Filter presupposes an explicit framework for identifying the relevant core outcomes...... for defining core areas of measurement ("Filter 2.0 Core Areas of Measurement") was presented at OMERACT 11 to explore areas of consensus and to consider whether already endorsed core outcome sets fit into this newly proposed framework. METHODS: Discussion groups critically reviewed the extent to which case......, presentation, and clarity of the framework were questioned. The discussion groups and subsequent feedback highlighted 20 such issues. CONCLUSION: These issues will require resolution to reach consensus on accepting the proposed Filter 2.0 framework of Core Areas as the basis for the selection of Core Outcome...

  7. Paul Rodgersi filter Kohilas

    Index Scriptorium Estoniae

    2000-01-01

    28. I Kohila keskkoolis kohaspetsiifiline skulptuur ja performance "Filter". Kooli 130. aastapäeva tähistava ettevõtmise eesotsas oli skulptor Paul Rodgers ja kaks viimase klassi noormeest ئ Marko Heinmäe, Hendrik Karm.

  8. Perspectives on Nonlinear Filtering

    KAUST Repository

    Law, Kody

    2015-01-07

    The solution to the problem of nonlinear filtering may be given either as an estimate of the signal (and ideally some measure of concentration), or as a full posterior distribution. Similarly, one may evaluate the fidelity of the filter either by its ability to track the signal or its proximity to the posterior filtering distribution. Hence, the field enjoys a lively symbiosis between probability and control theory, and there are plenty of applications which benefit from algorithmic advances, from signal processing, to econometrics, to large-scale ocean, atmosphere, and climate modeling. This talk will survey some recent theoretical results involving accurate signal tracking with noise-free (degenerate) dynamics in high-dimensions (infinite, in principle, but say d between 103 and 108 , depending on the size of your application and your computer), and high-fidelity approximations of the filtering distribution in low dimensions (say d between 1 and several 10s).

  9. Narrowband spectral filter based on biconical tapered fiber

    Science.gov (United States)

    Celaschi, Sergio; Malheiros-Silveira, Gilliard N.

    2018-02-01

    The ease of fabrication and compactness of devices based on tapered optical fibers contribute to its potential using in several applications ranging from telecommunication components to sensing devices. In this work, we proposed, fabricated, and characterized a spectral filter made of biconical taper from a coaxial optical fiber. This filter is defined by adiabatically tapering a depressed-cladding fiber. The adiabatic taper profile obtained during fabrication prevents the interference of other modes than HE11 and HE12 ones, which play the main role for the beating phenomenon and the filter response. The evolution of the fiber shapes during the pulling was modeled by two coupled partial differential equations, which relate the normalized cross-section area, and the axial velocity of the fiber elongation. These equations govern the mass and axial momentum conservation. The numerical results of the filter characteristics are in good accordance with the experimental ones. The filter was packaged in order to let it ready for using in optical communication bands. The characteristics are: free spectral range (FSR) of 6.19 nm, insertion loss bellow 0.5 dB, and isolation > 20 dB at C-band. Its transmission spectrum extends from 1200 to 1600 nm where the optical fiber core supports monomode transmission. Such characteristics may also be interesting to be applied in sensing applications. We show preliminary numerical results assuming a biconic taper embedded into a dielectric media, showing promising results for electro-optic sensing applications.

  10. ff;{·

    African Journals Online (AJOL)

    shown that as many as 1 in 17 CD8+ T cells in the peripheral ... antigen test in a subject who tests negative for HIV ... factors and antiretroviral therapy. .... antiretroviral drugs, which rely on attacking relevant ... implicated a failure of regenerative thymopoesis as an ... stem-cell precursors and failure of programming of na'ive T.

  11. FF Site Information

    Data.gov (United States)

    U.S. Environmental Protection Agency — This asset includes the EPA Federal Agency Hazardous Waste Compliance Docket (Docket), which is required by Section 120(c) of the Comprehensive Environmental...

  12. Spatial filter issues

    International Nuclear Information System (INIS)

    Murray, J.E.; Estabrook, K.G.; Milam, D.; Sell, W.D.; Van Wonterghem, R.M.; Feil, M.D.; Rubenchick, A.M.

    1996-01-01

    Experiments and calculations indicate that the threshold pressure in spatial filters for distortion of a transmitted pulse scales approximately as I O.2 and (F number-sign) 2 over the intensity range from 10 14 to 2xlO 15 W/CM 2 . We also demonstrated an interferometric diagnostic that will be used to measure the scaling relationships governing pinhole closure in spatial filters

  13. Microwave Resonators and Filters

    Science.gov (United States)

    2015-12-22

    1 Microwave Resonators and Filters Daniel E. Oates MIT Lincoln Laboratory 244 Wood St. Lexington, MA 02478 USA Email: oates@ll.mit.edu...explained in other chapters, the surface resistance of superconductors at microwave frequencies can be as much as three orders of magnitude lower than the...resonators and filters in the first edition of this handbook (Z.-Y. Shen 2003) discussed the then state of the art of microwave frequency applications

  14. Staging with spatial filters

    International Nuclear Information System (INIS)

    Glaze, J.

    1974-01-01

    It is known that small scale beam instabilities limit the focusable energy that can be achieved from a terawatt laser chain. Spatial filters are currently being used on CYCLOPS to ameliorate this problem. Realizing the full advantage of such a filter, however, may require certain staging modifications. A staging methodology is discussed that should be applicable to the CYCLOPS, 381, and SHIVA systems. Experiments are in progress on CYCLOPS that will address directly the utility of the proposed approach

  15. Initial Reactivity of Linkages and Monomer Rings in Lignin Pyrolysis Revealed by ReaxFF Molecular Dynamics.

    Science.gov (United States)

    Zhang, Tingting; Li, Xiaoxia; Guo, Li

    2017-10-24

    The initial conversion pathways of linkages and their linked monomer units in lignin pyrolysis were investigated comprehensively by ReaxFF MD simulations facilitated by the unique VARxMD for reaction analysis. The simulated molecular model contains 15 920 atoms and was constructed on the basis of Adler's softwood lignin model. The simulations uncover the initial conversion ratio of various linkages and their linked aryl monomers. For linkages and their linked monomer aryl rings of α-O-4, β-O-4 and α-O-4 & β-5, the C α /C β ether bond cracking dominates the initial pathway accounting for at least up to 80% of their consumption. For the linkage of β-β & γ-O-α, both the C α -O ether bond cracking and its linked monomer aryl ring opening are equally important. Ring-opening reactions dominate the initial consumption of other 4-O-5, 5-5, β-1, β-2, and β-5 linkages and their linked monomers. The ether bond cracking of C α -O and C β -O occurs at low temperature, and the aryl ring-opening reactions take place at relatively high temperature. The important intermediates leading to the stable aryl ring opening are the phenoxy radicals, the bridged five-membered and three-membered rings and the bridged six-membered and three-membered rings. In addition, the reactivity of a linkage and its monomer aryl ring may be affected by other linkages. The ether bond cracking of α-O-4 and β-O-4 linkages can activate its neighboring linkage or monomer ring through the formed phenoxy radicals as intermediates. The important intermediates revealed in this article should be of help in deepening the understanding of the controlling mechanism for producing aromatic chemicals from lignin pyrolysis.

  16. Inorganic UV filters

    Directory of Open Access Journals (Sweden)

    Eloísa Berbel Manaia

    2013-06-01

    Full Text Available Nowadays, concern over skin cancer has been growing more and more, especially in tropical countries where the incidence of UVA/B radiation is higher. The correct use of sunscreen is the most efficient way to prevent the development of this disease. The ingredients of sunscreen can be organic and/or inorganic sun filters. Inorganic filters present some advantages over organic filters, such as photostability, non-irritability and broad spectrum protection. Nevertheless, inorganic filters have a whitening effect in sunscreen formulations owing to the high refractive index, decreasing their esthetic appeal. Many techniques have been developed to overcome this problem and among them, the use of nanotechnology stands out. The estimated amount of nanomaterial in use must increase from 2000 tons in 2004 to a projected 58000 tons in 2020. In this context, this article aims to analyze critically both the different features of the production of inorganic filters (synthesis routes proposed in recent years and the permeability, the safety and other characteristics of the new generation of inorganic filters.

  17. Multicentre knowledge sharing and planning/dose audit on flattening filter free beams for SBRT lung

    Science.gov (United States)

    Hansen, C. R.; Sykes, J. R.; Barber, J.; West, K.; Bromley, R.; Szymura, K.; Fisher, S.; Sim, J.; Bailey, M.; Chrystal, D.; Deshpande, S.; Franji, I.; Nielsen, T. B.; Brink, C.; Thwaites, D. I.

    2015-01-01

    When implementing new technology into clinical practice, there will always be a need for large knowledge gain. The aim of this study was twofold, (I) audit the treatment planning and dose delivery of Flattening Filter Free (FFF) beam technology for Stereotactic Body Radiation Therapy (SBRT) of lung tumours across a range of treatment planning systems compared to the conventional Flatting Filter (FF) beams, (II) investigate how sharing knowledge between centres of different experience can improve plan quality. All vendor/treatment planning system (TPS) combinations investigated were able to produce acceptable treatment plans and the dose accuracy was clinically acceptable for all plans. By sharing knowledge between the different centres, the minor protocol violations (MPV) could be significantly reduced, from an average of 1.9 MPV per plan to 0.6 after such sharing of treatment planning knowledge. In particular, for the centres with less SBRT and/or volumetric- modulated arc therapy (VMAT) experience the MPV average per plan improved. All vendor/TPS combinations were also able to successfully deliver the FF and FFF SBRT VMAT plans. The plan quality and dose accuracy were found to be clinically acceptable.

  18. Multicentre knowledge sharing and planning/dose audit on flattening filter free beams for SBRT lung

    International Nuclear Information System (INIS)

    Hansen, C R; Nielsen, T B; Brink, C; Sykes, J R; Barber, J; West, K; Bromley, R; Szymura, K; Fisher, S; Sim, J; Bailey, M; Chrystal, D; Deshpande, S; Franji, I; Thwaites, D I

    2015-01-01

    When implementing new technology into clinical practice, there will always be a need for large knowledge gain. The aim of this study was twofold, (I) audit the treatment planning and dose delivery of Flattening Filter Free (FFF) beam technology for Stereotactic Body Radiation Therapy (SBRT) of lung tumours across a range of treatment planning systems compared to the conventional Flatting Filter (FF) beams, (II) investigate how sharing knowledge between centres of different experience can improve plan quality. All vendor/treatment planning system (TPS) combinations investigated were able to produce acceptable treatment plans and the dose accuracy was clinically acceptable for all plans. By sharing knowledge between the different centres, the minor protocol violations (MPV) could be significantly reduced, from an average of 1.9 MPV per plan to 0.6 after such sharing of treatment planning knowledge. In particular, for the centres with less SBRT and/or volumetric- modulated arc therapy (VMAT) experience the MPV average per plan improved. All vendor/TPS combinations were also able to successfully deliver the FF and FFF SBRT VMAT plans. The plan quality and dose accuracy were found to be clinically acceptable

  19. FF-i kuldsed elamused / Rain Tolk, Hille Hanso, Elina Pähklimägi jt. ; intervjueerinud Maria Ulfsak-Šeripova

    Index Scriptorium Estoniae

    2011-01-01

    Millised on eredaimad elamused, mida PÖFF aastate jooksul pakkunud on, vastavad režissöör ja näitleja Rain Tolk, EMT üritusturunduse juht Hille Hanso, näitlejad Elina Pähklimägi, Maria Avdjuško, kunstnik August Künnapu ja EFSA välissuhete juht Tristan Priimägi

  20. Design of UWB Filter with WLAN Notch

    Directory of Open Access Journals (Sweden)

    Harish Kumar

    2012-01-01

    Full Text Available UWB technology- (operating in broad frequency range of 3.1–10.6 GHz based filter with WLAN notch has shown great achievement for high-speed wireless communications. To satisfy the UWB system requirements, a band pass filter with a broad pass band width, low insertion loss, and high stop-band suppression are needed. UWB filter with wireless local area network (WLAN notch at 5.6 GHz and 3 dB fractional bandwidth of 109.5% using a microstrip structure is presented. Initially a two-transmission-pole UWB band pass filter in the frequency range 3.1–10.6 GHz is achieved by designing a parallel-coupled microstrip line with defective ground plane structure using GML 1000 substrate with specifications: dielectric constant 3.2 and thickness 0.762 mm at centre frequency 6.85 GHz. In this structure a λ/4 open-circuited stub is introduced to achieve the notch at 5.6 GHz to avoid the interference with WLAN frequency which lies in the desired UWB band. The design structure was simulated on electromagnetic circuit simulation software and fabricated by microwave integrated circuit technique. The measured VNA results show the close agreement with simulated results.

  1. Theoretical Investigation of Hydrogen Adsorption and Dissociation on Iron and Iron Carbide Surfaces Using the ReaxFF Reactive Force Field Method

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Chenyu; van Duin, Adri C.T.; Sorescu, Dan C.

    2012-06-01

    We have developed a ReaxFF reactive force field to describe hydrogen adsorption and dissociation on iron and iron carbide surfaces relevant for simulation of Fischer–Tropsch (FT) synthesis on iron catalysts. This force field enables large system (>>1000 atoms) simulations of hydrogen related reactions with iron. The ReaxFF force field parameters are trained against a substantial amount of structural and energetic data including the equations of state and heats of formation of iron and iron carbide related materials, as well as hydrogen interaction with iron surfaces and different phases of bulk iron. We have validated the accuracy and applicability of ReaxFF force field by carrying out molecular dynamics simulations of hydrogen adsorption, dissociation and recombination on iron and iron carbide surfaces. The barriers and reaction energies for molecular dissociation on these two types of surfaces have been compared and the effect of subsurface carbon on hydrogen interaction with iron surface is evaluated. We found that existence of carbon atoms at subsurface iron sites tends to increase the hydrogen dissociation energy barrier on the surface, and also makes the corresponding hydrogen dissociative state relatively more stable compared to that on bare iron. These properties of iron carbide will affect the dissociation rate of H{sub 2} and will retain more surface hydride species, thus influencing the dynamics of the FT synthesis process.

  2. f-f Magnetic polaron Wigner glass and anomalous superconductivity in U sub 1 sub - sub x Th sub x Be sub 1 sub 3

    CERN Document Server

    Kasuya, T

    2000-01-01

    Mechanisms of the anomalous properties in the heavy fermion superconductor UBe sub 1 sub 3 and its alloys, in particular for the Th dopings, are studied in detail based on the fundamental electronic states to be consistent with all the crucial experimental results. As the reference systems for the magnetic polaron formation, Ce monopnictides, as well as USb and UTe, are mentioned. From detailed systematic studies of the dilute alloy systems, it is postulated that the 5f states in UBe sub 1 sub 3 split into the well-localized core 5f GAMMA sup 2 sub 7 singlet state and other delocalized 5f states situated around the Fermi energy forming the f-f magnetic polarons through the strong intra-atomic ferromagnetic f-f exchange interaction. The accompanied lattice polarons are also shown to play important roles. In the p-d band states, the f-f exchange interaction and the intersite p-f mixing interactions for the p-f Kondo state are of nearly equal strengths causing a rich variety of delicately balanced states. For th...

  3. Development of active porous medium filters based on plasma textiles

    International Nuclear Information System (INIS)

    Kuznetsov, Ivan A.; Saveliev, Alexei V.; Rasipuram, Srinivasan; Kuznetsov, Andrey V.; Brown, Alan; Jasper, Warren

    2012-01-01

    Inexpensive, flexible, washable, and durable materials that serve as antimicrobial filters and self-decontaminating fabrics are needed to provide active protection to people in areas regularly exposed to various biohazards, such as hospitals and bio research labs working with pathogens. Airlines and cruise lines need such material to combat the spread of infections. In households these materials can be used in HVAC filters to fight indoor pollution, which is especially dangerous to people suffering from asthma. Efficient filtering materials are also required in areas contaminated by other types of hazardous dust particulates, such as nuclear dust. The primary idea that guided the undertaken study is that a microplasma-generating structure can be embedded in a textile fabric to generate a plasma sheath (''plasma shield'') that kills bacterial agents coming in contact with the fabric. The research resulted in the development of a plasma textile that can be used for producing new types of self-decontaminating garments, fabrics, and filter materials, capable of activating a plasma sheath that would filter, capture, and destroy any bacteriological agent deposited on its surface. This new material relies on the unique antimicrobial and catalytic properties of cold (room temperature) plasma that is benign to people and does not cause thermal damage to many polymer textiles, such as Nomex and polypropylene. The uniqueness of cold plasma as a disinfecting agent lies in the inability of bacteria to develop resistance to plasma exposure, as they can for antibiotics. Plasma textiles could thus be utilized for microbial destruction in active antimicrobial filters (for continuous decontamination and disinfection of large amounts of air) as well as in self-decontaminating surfaces and antibacterial barriers (for example, for creating local antiseptic or sterile environments around wounds and burns).

  4. Development of active porous medium filters based on plasma textiles

    Science.gov (United States)

    Kuznetsov, Ivan A.; Saveliev, Alexei V.; Rasipuram, Srinivasan; Kuznetsov, Andrey V.; Brown, Alan; Jasper, Warren

    2012-05-01

    Inexpensive, flexible, washable, and durable materials that serve as antimicrobial filters and self-decontaminating fabrics are needed to provide active protection to people in areas regularly exposed to various biohazards, such as hospitals and bio research labs working with pathogens. Airlines and cruise lines need such material to combat the spread of infections. In households these materials can be used in HVAC filters to fight indoor pollution, which is especially dangerous to people suffering from asthma. Efficient filtering materials are also required in areas contaminated by other types of hazardous dust particulates, such as nuclear dust. The primary idea that guided the undertaken study is that a microplasma-generating structure can be embedded in a textile fabric to generate a plasma sheath ("plasma shield") that kills bacterial agents coming in contact with the fabric. The research resulted in the development of a plasma textile that can be used for producing new types of self-decontaminating garments, fabrics, and filter materials, capable of activating a plasma sheath that would filter, capture, and destroy any bacteriological agent deposited on its surface. This new material relies on the unique antimicrobial and catalytic properties of cold (room temperature) plasma that is benign to people and does not cause thermal damage to many polymer textiles, such as Nomex and polypropylene. The uniqueness of cold plasma as a disinfecting agent lies in the inability of bacteria to develop resistance to plasma exposure, as they can for antibiotics. Plasma textiles could thus be utilized for microbial destruction in active antimicrobial filters (for continuous decontamination and disinfection of large amounts of air) as well as in self-decontaminating surfaces and antibacterial barriers (for example, for creating local antiseptic or sterile environments around wounds and burns).

  5. Development of active porous medium filters based on plasma textiles

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, Ivan A.; Saveliev, Alexei V.; Rasipuram, Srinivasan; Kuznetsov, Andrey V.; Brown, Alan; Jasper, Warren [Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC 27695 (United States); Textile Engineering Chemistry and Science, North Carolina State University, Raleigh, NC 27695 (United States)

    2012-05-15

    Inexpensive, flexible, washable, and durable materials that serve as antimicrobial filters and self-decontaminating fabrics are needed to provide active protection to people in areas regularly exposed to various biohazards, such as hospitals and bio research labs working with pathogens. Airlines and cruise lines need such material to combat the spread of infections. In households these materials can be used in HVAC filters to fight indoor pollution, which is especially dangerous to people suffering from asthma. Efficient filtering materials are also required in areas contaminated by other types of hazardous dust particulates, such as nuclear dust. The primary idea that guided the undertaken study is that a microplasma-generating structure can be embedded in a textile fabric to generate a plasma sheath (''plasma shield'') that kills bacterial agents coming in contact with the fabric. The research resulted in the development of a plasma textile that can be used for producing new types of self-decontaminating garments, fabrics, and filter materials, capable of activating a plasma sheath that would filter, capture, and destroy any bacteriological agent deposited on its surface. This new material relies on the unique antimicrobial and catalytic properties of cold (room temperature) plasma that is benign to people and does not cause thermal damage to many polymer textiles, such as Nomex and polypropylene. The uniqueness of cold plasma as a disinfecting agent lies in the inability of bacteria to develop resistance to plasma exposure, as they can for antibiotics. Plasma textiles could thus be utilized for microbial destruction in active antimicrobial filters (for continuous decontamination and disinfection of large amounts of air) as well as in self-decontaminating surfaces and antibacterial barriers (for example, for creating local antiseptic or sterile environments around wounds and burns).

  6. Soft X-ray multilayers and filters

    CERN Document Server

    Wang Zhan Shan; Tang Wei Xing; Qin Shuji; Zhou Bing; Chen Ling Ya

    2002-01-01

    The periodic and non-periodic multilayers were designed by using a random number to change each layer and a suitable merit function. Ion beam sputtering and magnetron sputtering were used to fabricate various multilayers and beam splitters in soft X-ray range. The characterization of multilayers by small angle X-ray diffraction, Auger electron spectroscopy, Rutherford back scattering spectroscopy and reflectivity illustrated the multilayers had good structures and smooth interlayers. The reflectivity and transmission of a beam splitter is about 5%. The fabrication and transmission properties of Ag, Zr were studied. The Rutherford back scattering spectroscopy and auger electron spectroscopy were used to investigate the contents and distributions of impurities and influence on qualities of filters. The attenuation coefficients were corrected by the data obtained by measurements

  7. Fused-filament 3D printing (3DP) for fabrication of tablets.

    Science.gov (United States)

    Goyanes, Alvaro; Buanz, Asma B M; Basit, Abdul W; Gaisford, Simon

    2014-12-10

    The use of fused-filament 3D printing (FF 3DP) to fabricate individual tablets is demonstrated. The technology permits the manufacture of tablets containing drug doses tailored to individual patients, or to fabrication of tablets with specific drug-release profiles. Commercially produced polyvinyl alcohol (PVA) filament was loaded with a model drug (fluorescein) by swelling of the polymer in ethanolic drug solution. A final drug-loading of 0.29% w/w was achieved. Tablets of PVA/fluorescein (10 mm diameter) were printed using a 3D printer. It was found that changing the degree of infill percentage in the printer software varied the weight and volume of the printed tablets. The tablets were mechanically strong and no significant thermal degradation of the active occurred during printing. Dissolution tests were conducted in modified Hank's buffer. The results showed release profiles were dependent on the infill percentage used to print the tablet. The study indicates that FF 3DP has the potential to offer a new solution for fabricating personalized-dose medicines or unit dosage forms with controlled-release profiles. In addition, the low cost of FDM printers means the paradigm of extemporaneous or point-of-use manufacture of personalized-dose tablets is both feasible and attainable. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Choosing and using astronomical filters

    CERN Document Server

    Griffiths, Martin

    2014-01-01

    As a casual read through any of the major amateur astronomical magazines will demonstrate, there are filters available for all aspects of optical astronomy. This book provides a ready resource on the use of the following filters, among others, for observational astronomy or for imaging: Light pollution filters Planetary filters Solar filters Neutral density filters for Moon observation Deep-sky filters, for such objects as galaxies, nebulae and more Deep-sky objects can be imaged in much greater detail than was possible many years ago. Amateur astronomers can take

  9. Influence of intramolecular f-f interactions on nuclear spin driven quantum tunneling of magnetizations in quadruple-decker phthalocyanine complexes containing two terbium or dysprosium magnetic centers.

    Science.gov (United States)

    Fukuda, Takamitsu; Matsumura, Kazuya; Ishikawa, Naoto

    2013-10-10

    Nuclear spin driven quantum tunneling of magnetization (QTM) phenomena, which arise from admixture of more than two orthogonal electronic spin wave functions through the couplings with those of the nuclear spins, are one of the important magnetic relaxation processes in lanthanide single molecule magnets (SMMs) in the low temperature range. Although recent experimental studies have indicated that the presence of the intramolecular f-f interactions affects their magnetic relaxation processes, little attention has been given to their mechanisms and, to the best of our knowledge, no rational theoretical models have been proposed for the interpretations of how the nuclear spin driven QTMs are influenced by the f-f interactions. Since quadruple-decker phthalocyanine complexes with two terbium or dysprosium ions as the magnetic centers show moderate f-f interactions, these are appropriate to investigate the influence of the f-f interactions on the dynamic magnetic relaxation processes. In the present paper, a theoretical model including ligand field (LF) potentials, hyperfine, nuclear quadrupole, magnetic dipolar, and the Zeeman interactions has been constructed to understand the roles of the nuclear spins for the QTM processes, and the resultant Zeeman plots are obtained. The ac susceptibility measurements of the magnetically diluted quadruple-decker monoterbium and diterbium phthalocyanine complexes, [Tb-Y] and [Tb-Tb], have indicated that the presence of the f-f interactions suppresses the QTMs in the absence of the external magnetic field (H(dc)) being consistent with previous reports. On the contrary, the faster magnetic relaxation processes are observed for [Tb-Tb] than [Tb-Y] at H(dc) = 1000 Oe, clearly demonstrating that the QTMs are rather enhanced in the presence of the external magnetic field. Based on the calculated Zeeman diagrams, these observations can be attributed to the enhanced nuclear spin driven QTMs for [Tb-Tb]. At the H(dc) higher than 2000 Oe, the

  10. Anti-clogging filter system

    Science.gov (United States)

    Brown, Erik P.

    2015-05-19

    An anti-clogging filter system for filtering a fluid containing large particles and small particles includes an enclosure with at least one individual elongated tubular filter element in the enclosure. The individual elongated tubular filter element has an internal passage, a closed end, an open end, and a filtering material in or on the individual elongated tubular filter element. The fluid travels through the open end of the elongated tubular element and through the internal passage and through the filtering material. An anti-clogging element is positioned on or adjacent the individual elongated tubular filter element and provides a fluid curtain that preferentially directs the larger particulates to one area of the filter material allowing the remainder of the filter material to remain more efficient.

  11. Multilevel ensemble Kalman filtering

    KAUST Repository

    Hoel, Haakon

    2016-01-08

    The ensemble Kalman filter (EnKF) is a sequential filtering method that uses an ensemble of particle paths to estimate the means and covariances required by the Kalman filter by the use of sample moments, i.e., the Monte Carlo method. EnKF is often both robust and efficient, but its performance may suffer in settings where the computational cost of accurate simulations of particles is high. The multilevel Monte Carlo method (MLMC) is an extension of classical Monte Carlo methods which by sampling stochastic realizations on a hierarchy of resolutions may reduce the computational cost of moment approximations by orders of magnitude. In this work we have combined the ideas of MLMC and EnKF to construct the multilevel ensemble Kalman filter (MLEnKF) for the setting of finite dimensional state and observation spaces. The main ideas of this method is to compute particle paths on a hierarchy of resolutions and to apply multilevel estimators on the ensemble hierarchy of particles to compute Kalman filter means and covariances. Theoretical results and a numerical study of the performance gains of MLEnKF over EnKF will be presented. Some ideas on the extension of MLEnKF to settings with infinite dimensional state spaces will also be presented.

  12. Multilevel ensemble Kalman filtering

    KAUST Repository

    Hoel, Haakon; Chernov, Alexey; Law, Kody; Nobile, Fabio; Tempone, Raul

    2016-01-01

    The ensemble Kalman filter (EnKF) is a sequential filtering method that uses an ensemble of particle paths to estimate the means and covariances required by the Kalman filter by the use of sample moments, i.e., the Monte Carlo method. EnKF is often both robust and efficient, but its performance may suffer in settings where the computational cost of accurate simulations of particles is high. The multilevel Monte Carlo method (MLMC) is an extension of classical Monte Carlo methods which by sampling stochastic realizations on a hierarchy of resolutions may reduce the computational cost of moment approximations by orders of magnitude. In this work we have combined the ideas of MLMC and EnKF to construct the multilevel ensemble Kalman filter (MLEnKF) for the setting of finite dimensional state and observation spaces. The main ideas of this method is to compute particle paths on a hierarchy of resolutions and to apply multilevel estimators on the ensemble hierarchy of particles to compute Kalman filter means and covariances. Theoretical results and a numerical study of the performance gains of MLEnKF over EnKF will be presented. Some ideas on the extension of MLEnKF to settings with infinite dimensional state spaces will also be presented.

  13. Serum levels of interleukin-22, cardiometabolic risk factors and incident type 2 diabetes: KORA F4/FF4 study.

    Science.gov (United States)

    Herder, Christian; Kannenberg, Julia M; Carstensen-Kirberg, Maren; Huth, Cornelia; Meisinger, Christa; Koenig, Wolfgang; Peters, Annette; Rathmann, Wolfgang; Roden, Michael; Thorand, Barbara

    2017-01-31

    Interleukin-22 (IL-22) has beneficial effects on body weight, insulin resistance and inflammation in different mouse models, but its relevance for the development of type 2 diabetes in humans is unknown. We aimed to identify correlates of serum IL-22 levels and to test the hypothesis that higher IL-22 levels are associated with lower diabetes incidence. Cross-sectional associations between serum IL-22, cardiometabolic risk factors and glucose tolerance status were investigated in 1107 persons of the population-based KORA F4 study. The prospective association between serum IL-22 and incident type 2 diabetes was assessed in 504 initially non-diabetic study participants in both the KORA F4 study and its 7-year follow-up examination KORA FF4, 76 of whom developed diabetes. Male sex, current smoking, lower HDL cholesterol, lower estimated glomerular filtration rate and higher serum interleukin-1 receptor antagonist were associated with higher IL-22 levels after adjustment for confounders (all P < 0.05). Serum IL-22 showed no associations with glucose tolerance status, prediabetes or type 2 diabetes. Baseline serum IL-22 levels (median, 25th/75th percentiles) for incident type 2 diabetes cases and non-cases were 6.28 (1.95; 12.35) and 6.45 (1.95; 11.80) pg/ml, respectively (age and sex-adjusted P = 0.744). The age and sex-adjusted OR (95% CI) per doubling of IL-22 for incident type 2 diabetes of 1.02 (0.85; 1.23) was almost unchanged after consideration of further confounders. High serum levels of IL-22 were positively rather than inversely associated with several cardiometabolic risk factors. However, these associations did not translate into an increased risk for type 2 diabetes. Thus, our data argue against the utility of IL-22 as biomarker for prevalent or incident type 2 diabetes in humans, but identify potential determinants of IL-22 levels which merits further research in the context of cardiovascular diseases.

  14. Adaptive digital filters

    CERN Document Server

    Kovačević, Branko; Milosavljević, Milan

    2013-01-01

    “Adaptive Digital Filters” presents an important discipline applied to the domain of speech processing. The book first makes the reader acquainted with the basic terms of filtering and adaptive filtering, before introducing the field of advanced modern algorithms, some of which are contributed by the authors themselves. Working in the field of adaptive signal processing requires the use of complex mathematical tools. The book offers a detailed presentation of the mathematical models that is clear and consistent, an approach that allows everyone with a college level of mathematics knowledge to successfully follow the mathematical derivations and descriptions of algorithms.   The algorithms are presented in flow charts, which facilitates their practical implementation. The book presents many experimental results and treats the aspects of practical application of adaptive filtering in real systems, making it a valuable resource for both undergraduate and graduate students, and for all others interested in m...

  15. Updating the OMERACT filter

    DEFF Research Database (Denmark)

    D'Agostino, Maria-Antonietta; Boers, Maarten; Kirwan, John

    2014-01-01

    OBJECTIVE: The Outcome Measures in Rheumatology (OMERACT) Filter provides a framework for the validation of outcome measures for use in rheumatology clinical research. However, imaging and biochemical measures may face additional validation challenges because of their technical nature. The Imaging...... using the original OMERACT Filter and the newly proposed structure. Breakout groups critically reviewed the extent to which the candidate biomarkers complied with the proposed stepwise approach, as a way of examining the utility of the proposed 3-dimensional structure. RESULTS: Although...... was obtained for a proposed tri-axis structure to assess validation of imaging and soluble biomarkers; nevertheless, additional work is required to better evaluate its place within the OMERACT Filter 2.0....

  16. Automated electronic filter design

    CERN Document Server

    Banerjee, Amal

    2017-01-01

    This book describes a novel, efficient and powerful scheme for designing and evaluating the performance characteristics of any electronic filter designed with predefined specifications. The author explains techniques that enable readers to eliminate complicated manual, and thus error-prone and time-consuming, steps of traditional design techniques. The presentation includes demonstration of efficient automation, using an ANSI C language program, which accepts any filter design specification (e.g. Chebyschev low-pass filter, cut-off frequency, pass-band ripple etc.) as input and generates as output a SPICE(Simulation Program with Integrated Circuit Emphasis) format netlist. Readers then can use this netlist to run simulations with any version of the popular SPICE simulator, increasing accuracy of the final results, without violating any of the key principles of the traditional design scheme.

  17. Stack filter classifiers

    Energy Technology Data Exchange (ETDEWEB)

    Porter, Reid B [Los Alamos National Laboratory; Hush, Don [Los Alamos National Laboratory

    2009-01-01

    Just as linear models generalize the sample mean and weighted average, weighted order statistic models generalize the sample median and weighted median. This analogy can be continued informally to generalized additive modeels in the case of the mean, and Stack Filters in the case of the median. Both of these model classes have been extensively studied for signal and image processing but it is surprising to find that for pattern classification, their treatment has been significantly one sided. Generalized additive models are now a major tool in pattern classification and many different learning algorithms have been developed to fit model parameters to finite data. However Stack Filters remain largely confined to signal and image processing and learning algorithms for classification are yet to be seen. This paper is a step towards Stack Filter Classifiers and it shows that the approach is interesting from both a theoretical and a practical perspective.

  18. Quantum reality filters

    International Nuclear Information System (INIS)

    Gudder, Stan

    2010-01-01

    An anhomomorphic logic A* is the set of all possible realities for a quantum system. Our main goal is to find the 'actual reality' Φ a element of A* for the system. Reality filters are employed to eliminate unwanted potential realities until only φ a remains. In this paper, we consider three reality filters that are constructed by means of quantum integrals. A quantum measure μ can generate or actualize a Φ element of A* if μ(A) is a quantum integral with respect to φ for a density function f over events A. In this sense, μ is an 'average' of the truth values of φ with weights given by f. We mainly discuss relations between these filters and their existence and uniqueness properties. For example, we show that a quadratic reality generated by a quantum measure is unique. In this case we obtain the unique actual quadratic reality.

  19. Stresses and Temperature Stability of Dense Wavelength Division Multiplexing Filters Prepared by Reactive Ion-Assisted E-Gun Evaporation

    Science.gov (United States)

    Wei, Chao-Tsang; Shieh, Han-Ping D.

    2005-10-01

    In this paper, we report the in situ measurement of the temperature stability of narrow-band-pass filters on different types of substrate, for dense wavelength division multiplexing (DWDM) filters in optical-fiber transmission systems. The DWDM filters were designed as all-dielectric Fabry-Perot filters and fabricated by reactive ion-assisted deposition. Ta2O5 and SiO2 were used as high- and low-refractive-index layers, respectively, for constructing the DWDM filters. The accuracy and stability of the coating process were evaluated for fabricating the DWDM filters for the temperature stability of the center wavelength. The center wavelength shift was determined to be greatly dependent on the coefficient of thermal expansion of the substrate on which the filter is deposited.

  20. Filters in topology optimization

    DEFF Research Database (Denmark)

    Bourdin, Blaise

    1999-01-01

    In this article, a modified (``filtered'') version of the minimum compliance topology optimization problem is studied. The direct dependence of the material properties on its pointwise density is replaced by a regularization of the density field using a convolution operator. In this setting...... it is possible to establish the existence of solutions. Moreover, convergence of an approximation by means of finite elements can be obtained. This is illustrated through some numerical experiments. The ``filtering'' technique is also shown to cope with two important numerical problems in topology optimization...

  1. Alarm filtering and presentation

    International Nuclear Information System (INIS)

    Bray, M.A.

    1989-01-01

    This paper discusses alarm filtering and presentation in the control room of nuclear and other process control plants. Alarm generation and presentation is widely recognized as a general process control problem. Alarm systems often fail to provide meaningful alarms to operators. Alarm generation and presentation is an area in which computer aiding is feasible and provides clear benefits. Therefore, researchers have developed several computerized alarm filtering and presentation approaches. This paper discusses problems associated with alarm generation and presentation. Approaches to improving the alarm situation and installation issues of alarm system improvements are discussed. The impact of artificial intelligence (AI) technology on alarm system improvements is assessed. (orig.)

  2. Radiosurgery with flattening-filter-free techniques in the treatment of brain metastases. Plan comparison and early clinical evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Rieber, J.; Tonndorf-Martini, E.; Schramm, O.; Rhein, B.; Stefanowicz, S.; Lindel, K.; Debus, J.; Rieken, S. [University Hospital Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); Heidelberg Institute of Radiation Oncology, Heidelberg (Germany); Kappes, J. [Heidelberg University, Translational Research Unit, Thoraxklinik, Heidelberg (Germany); Heidelberg University, Department of Pneumology, Thoraxklinik, Heidelberg (Germany); Member of the German Centre for Lung Research (DZL), Translational Lung Research Centre Heidelberg (TLRC-H), Heidelberg (Germany); Hoffmann, H. [Heidelberg University, Translational Research Unit, Thoraxklinik, Heidelberg (Germany); Heidelberg University, Department of Thoracic Surgery, Thoraxklinik, Heidelberg (Germany); Member of the German Centre for Lung Research (DZL), Translational Lung Research Centre Heidelberg (TLRC-H), Heidelberg (Germany)

    2016-11-15

    Radiosurgical treatment of brain metastases is well established in daily clinical routine. Utilization of flattening-filter-free beams (FFF) may allow for more rapid delivery of treatment doses and improve clinical comfort. Hence, we compared plan quality and efficiency of radiosurgery in FFF mode to FF techniques. Between November 2014 and June 2015, 21 consecutive patients with 25 brain metastases were treated with stereotactic radiosurgery (SRS) in FFF mode. Brain metastases received dose-fractionation schedules of 1 x 20 Gy or 1 x 18 Gy, delivered to the conformally enclosing 80 % isodose. Three patients with critically localized or large (>3 cm) brain metastases were treated with 6 x 5 Gy. Plan quality and efficiency were evaluated by analyzing conformity, dose gradients, dose to healthy brain tissue, treatment delivery time, and number of monitor units. FFF plans were compared to those using the FF method, and early clinical outcome and toxicity were assessed. FFF mode resulted in significant reductions in beam-on time (p < 0.001) and mean brain dose (p = 0.001) relative to FF-mode comparison plans. Furthermore, significant improvements in dose gradients and sharper dose falloffs were found for SRS in FFF mode (-1.1 %, -29.6 %; p ≤ 0.003), but conformity was slightly superior in SRS in FF mode (-1.3 %; p = 0.001). With a median follow-up time of 5.1 months, 6-month overall survival was 63.3 %. Local control was observed in 24 of 25 brain metastases (96 %). SRS in FFF mode is time efficient and provides similar plan quality with the opportunity of slightly reduced dose exposure to healthy brain tissue when compared to SRS in FF mode. Clinical outcomes appear promising and show only modest treatment-related toxicity. (orig.) [German] Die radiochirurgische Behandlung (SRS) von Hirnmetastasen wird vielfach in der klinischen Routine durchgefuehrt. Die zusaetzliche Anwendung von ausgleichsfilterfreien Bestrahlungstechniken (FFF) kann die Bestrahlungszeit

  3. Wideband filter radiometers for blackbody temperature measurements

    Science.gov (United States)

    Boivin, L. P.; Bamber, C.; Gaertner, A. A.; Gerson, R. K.; Woods, D. J.; Woolliams, E. R.

    2010-10-01

    The use of high-temperature blackbody (HTBB) radiators to realize primary spectral irradiance scales requires that the operating temperature of the HTBB be accurately determined. We have developed five filter radiometers (FRs) to measure the temperature of the National Research Council of Canada's HTBB. The FRs are designed to minimize sensitivity to ambient temperature fluctuations. They incorporate air-spaced colored glass filters and a Si photodiode detector that are housed in a cell whose temperature is controlled to ±0.1°C by means of annular thermoelectric elements at the front and rear of the cell. These wideband filter radiometers operate in four different wavelength bands. The spectral responsivity measurements were performed in an underfill geometry for a power-mode calibration that is traceable to NRC's cryogenic radiometer. The spectral temperature sensitivity of each of these FRs has been measured. The apertures for these FRs were cold-formed by swaging machine-cut apertures onto precision dowel pins. A description of the filter radiometer design, fabrication and testing, together with a detailed uncertainty analysis, is presented. We derive the equations that relate the spectral irradiance measured by the FRs to the spectral radiance and temperature of the HTBB, and deal specifically with the change of index of refraction over the path of the radiation from the interior of the HTBB to the FRs. We believe these equations are more accurate than recently published derivations. Our measurements of the operating temperature of our HTBB working at temperatures near 2500 K, 2700 K and 2900 K, together with measurements using a pyrometer, show agreement between the five filter radiometers and with the pyrometer to within the estimated uncertainties.

  4. Fully integrated low-loss band-pass filters for wireless applications

    International Nuclear Information System (INIS)

    Rais-Zadeh, M; Kapoor, A; Lavasani, H M; Ayazi, F

    2009-01-01

    Fully integrated low insertion loss micromachined band-pass filters are designed and fabricated on the silicon substrate (ρ = 10–20 Ω cm, ε r = 11.9) for UHF applications. Filters are made of silver, which has the highest conductivity of all metals, to minimize the ohmic loss. A detailed analysis for realizing low insertion loss and high out-of-band rejection filters using elliptic magnitude characteristics is presented, and a comprehensive model to take into account inductive parasitics of the interconnects is developed. Temperature characteristics of the filters are measured and show stable performance. The presented filters are different from the previously reported lumped element filters in that all filters are fully integrated on silicon substrate and occupy a remarkably smaller die area. Two filters are fabricated using the silver micromachining technique with center frequencies at 1.05 and 1.35 GHz. The filters have a constant 3 dB bandwidth of 300 MHz (28.6% and 22.2%) and an insertion loss of 1.4–1.7 dB. The low insertion loss and CMOS compatibility make the presented filters suitable candidates for radio frequency integrated circuits

  5. High-Thermal-Conductivity Fabrics

    Science.gov (United States)

    Chibante, L. P. Felipe

    2012-01-01

    Heat management with common textiles such as nylon and spandex is hindered by the poor thermal conductivity from the skin surface to cooling surfaces. This innovation showed marked improvement in thermal conductivity of the individual fibers and tubing, as well as components assembled from them. The problem is centered on improving the heat removal of the liquid-cooled ventilation garments (LCVGs) used by astronauts. The current design uses an extensive network of water-cooling tubes that introduces bulkiness and discomfort, and increases fatigue. Range of motion and ease of movement are affected as well. The current technology is the same as developed during the Apollo program of the 1960s. Tubing material is hand-threaded through a spandex/nylon mesh layer, in a series of loops throughout the torso and limbs such that there is close, form-fitting contact with the user. Usually, there is a nylon liner layer to improve comfort. Circulating water is chilled by an external heat exchanger (sublimator). The purpose of this innovation is to produce new LCVG components with improved thermal conductivity. This was addressed using nanocomposite engineering incorporating high-thermalconductivity nanoscale fillers in the fabric and tubing components. Specifically, carbon nanotubes were added using normal processing methods such as thermoplastic melt mixing (compounding twin screw extruder) and downstream processing (fiber spinning, tubing extrusion). Fibers were produced as yarns and woven into fabric cloths. The application of isotropic nanofillers can be modeled using a modified Nielsen Model for conductive fillers in a matrix based on Einstein s viscosity model. This is a drop-in technology with no additional equipment needed. The loading is limited by the ability to maintain adequate dispersion. Undispersed materials will plug filtering screens in processing equipment. Generally, the viscosity increases were acceptable, and allowed the filled polymers to still be

  6. Statistically-Efficient Filtering in Impulsive Environments: Weighted Myriad Filters

    Directory of Open Access Journals (Sweden)

    Juan G. Gonzalez

    2002-01-01

    Full Text Available Linear filtering theory has been largely motivated by the characteristics of Gaussian signals. In the same manner, the proposed Myriad Filtering methods are motivated by the need for a flexible filter class with high statistical efficiency in non-Gaussian impulsive environments that can appear in practice. Myriad filters have a solid theoretical basis, are inherently more powerful than median filters, and are very general, subsuming traditional linear FIR filters. The foundation of the proposed filtering algorithms lies in the definition of the myriad as a tunable estimator of location derived from the theory of robust statistics. We prove several fundamental properties of this estimator and show its optimality in practical impulsive models such as the α-stable and generalized-t. We then extend the myriad estimation framework to allow the use of weights. In the same way as linear FIR filters become a powerful generalization of the mean filter, filters based on running myriads reach all of their potential when a weighting scheme is utilized. We derive the “normal” equations for the optimal myriad filter, and introduce a suboptimal methodology for filter tuning and design. The strong potential of myriad filtering and estimation in impulsive environments is illustrated with several examples.

  7. Fresnel Lenses fabricated by femtosecond laser micromachining on Polymer 1D Photonic Crystal

    Directory of Open Access Journals (Sweden)

    Guduru Surya S.K.

    2013-11-01

    Full Text Available We report the fabrication of micro Fresnel lenses by femtosecond laser surface ablation on polymer 1D photonic crystals. This device is designed to focus the transmitted wavelength of the photonic crystal and filter the wavelengths corresponding to the photonic band gap region. Integration of such devices in a wavelength selective light harvesting and filtering microchip can be achieved.

  8. The ATLAS event filter

    CERN Document Server

    Beck, H P; Boissat, C; Davis, R; Duval, P Y; Etienne, F; Fede, E; Francis, D; Green, P; Hemmer, F; Jones, R; MacKinnon, J; Mapelli, Livio P; Meessen, C; Mommsen, R K; Mornacchi, Giuseppe; Nacasch, R; Negri, A; Pinfold, James L; Polesello, G; Qian, Z; Rafflin, C; Scannicchio, D A; Stanescu, C; Touchard, F; Vercesi, V

    1999-01-01

    An overview of the studies for the ATLAS Event Filter is given. The architecture and the high level design of the DAQ-1 prototype is presented. The current status if the prototypes is briefly given. Finally, future plans and milestones are given. (11 refs).

  9. Spectral Ensemble Kalman Filters

    Czech Academy of Sciences Publication Activity Database

    Mandel, Jan; Kasanický, Ivan; Vejmelka, Martin; Fuglík, Viktor; Turčičová, Marie; Eben, Kryštof; Resler, Jaroslav; Juruš, Pavel

    2014-01-01

    Roč. 11, - (2014), EMS2014-446 [EMS Annual Meeting /14./ & European Conference on Applied Climatology (ECAC) /10./. 06.10.2014-10.10.2014, Prague] R&D Projects: GA ČR GA13-34856S Grant - others:NSF DMS-1216481 Institutional support: RVO:67985807 Keywords : data assimilation * spectral filter Subject RIV: DG - Athmosphere Sciences, Meteorology

  10. Characterization of magnesium phosphate ceramics incorporating off-gas filters

    International Nuclear Information System (INIS)

    Yang, Jae Hwan; Lee, Chang Hwa; Heo, Chul Min; Jeon, Min Ku; Kang, Kweon Ho

    2011-01-01

    Radioactive cesium (Cs-137) and technetium (Tc-99) are discharged from the spent fuel as gaseous forms during the head-end process in pyroprocess. These off-gases are safely trapped via porous ceramic filters made of fly ash and calcium based material. Spent filters have to be treated, converted into proper waste forms in order to be disposed safely at a repository. Conventional technology used to make waste forms such as vitrification requires high temperature and complex process. In this study, we report a promising method to stabilize spent filters containing cesium and technetium using magnesium phosphate ceramics. Simulated spent filters were fabricated by vaporizing nonradioactive cesium and rhenium (a surrogate of Tc) through the voloxidizer. The crushed filters were mixed with raw materials of magnesium phosphate ceramics, to be stabilized in the phosphate ceramic matrix. Characterization of the waste forms was made by the compressive strength test, apparent porosity, XRD analysis, and SEM analysis. The sample containing filters showed the excellent mechanical property, with the highest compressive strength of 38.1 MPa in the sample with 30 wt% of Cs-filter. Microstructural analysis suggests that wastes are embedded in the crystalline phase formed by an acid-base reaction. (author)

  11. Characterisation of flattening filter free (FFF) beam properties for initial beam set-up and routine QA, independent of flattened beams

    Science.gov (United States)

    Paynter, D.; Weston, S. J.; Cosgrove, V. P.; Thwaites, D. I.

    2018-01-01

    Flattening filter free (FFF) beams have reached widespread use for clinical treatment deliveries. The usual methods for FFF beam characterisation for their quality assurance (QA) require the use of associated conventional flattened beams (cFF). Methods for QA of FFF without the need to use associated cFF beams are presented and evaluated against current methods for both FFF and cFF beams. Inflection point normalisation is evaluated against conventional methods for the determination of field size and penumbra for field sizes from 3 cm  ×  3 cm to 40 cm  ×  40cm at depths from dmax to 20 cm in water for matched and unmatched FFF beams and for cFF beams. A method for measuring symmetry in the cross plane direction is suggested and evaluated as FFF beams are insensitive to symmetry changes in this direction. Methods for characterising beam energy are evaluated and the impact of beam energy on profile shape compared to that of cFF beams. In-plane symmetry can be measured, as can cFF beams, using observed changes in profile, whereas cross-plane symmetry can be measured by acquiring profiles at collimator angles 0 and 180. Beam energy and ‘unflatness’ can be measured as with cFF beams from observed shifts in profile with changing beam energy. Normalising the inflection points of FFF beams to 55% results in an equivalent penumbra and field size measurement within 0.5 mm of conventional methods with the exception of 40 cm  ×  40 cm fields at a depth of 20 cm. New proposed methods are presented that make it possible to independently carry out set up and QA measurements on beam energy, flatness, symmetry and field size of an FFF beam without the need to reference to an equivalent flattened beam of the same energy. The methods proposed can also be used to carry out this QA for flattened beams, resulting in universal definitions and methods for MV beams. This is presented for beams produced by an Elekta linear accelerator, but is

  12. Porous ceramic materials for micro filtration processes I: Al2 O3 fabrication and characterization

    International Nuclear Information System (INIS)

    Salas K, J.; Reyes M, P.E.; Piderit A, G.

    1992-01-01

    Ceramic filters in separation processes are becoming more important every day. The use of these filters or membranes in the micro and ultrafiltration range, which origin goes back to the nuclear industry for uranium isotopes separation by gaseous diffusion and radioactive waste treatments, significantly improves some industrial processes efficiency. The present work describes the research done in the filters, or ceramic membrane supports fabrication field, the obtained operational results and their relation with the microstructure. (author)

  13. DEMONSTRATION BULLETIN: COLLOID POLISHING FILTER METHOD - FILTER FLOW TECHNOLOGY, INC.

    Science.gov (United States)

    The Filter Flow Technology, Inc. (FFT) Colloid Polishing Filter Method (CPFM) was tested as a transportable, trailer mounted, system that uses sorption and chemical complexing phenomena to remove heavy metals and nontritium radionuclides from water. Contaminated waters can be pro...

  14. Filter assembly for metallic and intermetallic tube filters

    Science.gov (United States)

    Alvin, Mary Anne; Lippert, Thomas E.; Bruck, Gerald J.; Smeltzer, Eugene E.

    2001-01-01

    A filter assembly (60) for holding a filter element (28) within a hot gas cleanup system pressure vessel is provided, containing: a filter housing (62), said filter housing having a certain axial length and having a peripheral sidewall, said sidewall defining an interior chamber (66); a one piece, all metal, fail-safe/regenerator device (68) within the interior chamber (66) of the filter housing (62) and/or extending beyond the axial length of the filter housing, said device containing an outward extending radial flange (71) within the filter housing for seating an essential seal (70), the device also having heat transfer media (72) disposed inside and screens (80) for particulate removal; one compliant gasket (70) positioned next to and above the outward extending radial flange of the fail-safe/regenerator device; and a porous metallic corrosion resistant superalloy type filter element body welded at the bottom of the metal fail-safe/regenerator device.

  15. Estimation and control in HTGR fuel rod fabrication

    International Nuclear Information System (INIS)

    Downing, D.J.; Bailey, J.M.

    1980-01-01

    A control algorithm has been derived for an HTGR Fuel Rod Fabrication Process utilizing the method of G.E.P. Box and G.M. Jenkins. The estimator is a Kalman filter and is compared with a Least Square estimator and a standard control chart. The effects of system delays are presented. 1 ref

  16. Estimation and control in HTGR fuel rod fabrication

    International Nuclear Information System (INIS)

    Downing, D.J.; Bailey, M.J.

    1980-01-01

    A control algorithm has been derived for a HTGR Fuel Rod Fabrication Process utilizing the method of Box and Jenkins. The estimator is a Kalman filter and is compared with a Least Square estimator and a standard control chart. The effects of system delays are presented

  17. Digital Simulation of a Hybrid Active Filter - An Active Filter in Series with a Shunt Passive Filter

    OpenAIRE

    Sitaram, Mahesh I; Padiyar, KR; Ramanarayanan, V

    1998-01-01

    Active filters have long been in use for the filtering of power system load harmonics. In this paper, the digital simulation results of a hybrid active power filter system for a rectifier load are presented. The active filter is used for filtering higher order harmonics as the dominant harmonics are filtered by the passive filter. This reduces the rating of the active filter significantly. The DC capacitor voltage of the active filter is controlled using a PI controller.

  18. Experimental study of filter cake formation on different filter media

    International Nuclear Information System (INIS)

    Saleem, M.

    2009-01-01

    Removal of particulate matter from gases generated in the process industry is important for product recovery as well as emission control. Dynamics of filtration plant depend on operating conditions. The models, that predict filter plant behaviour, involve empirical resistance parameters which are usually derived from limited experimental data and are characteristics of the filter media and filter cake (dust deposited on filter medium). Filter cake characteristics are affected by the nature of filter media, process parameters and mode of filter regeneration. Removal of dust particles from air is studied in a pilot scale jet pulsed bag filter facility resembling closely to the industrial filters. Limestone dust and ambient air are used in this study with two widely different filter media. All important parameters like pressure drop, gas flow rate, dust settling, are recorded continuously at 1s interval. The data is processed for estimation of the resistance parameters. The pressure drop rise on test filter media is compared. Results reveal that the surface of filter media has an influence on pressure drop rise (concave pressure drop rise). Similar effect is produced by partially jet pulsed filter surface. Filter behaviour is also simulated using estimated parameters and a simplified model and compared with the experimental results. Distribution of cake area load is therefore an important aspect of jet pulse cleaned bag filter modeling. Mean specific cake resistance remains nearly constant on thoroughly jet pulse cleaned membrane coated filter bags. However, the trend can not be confirmed without independent cake height and density measurements. Thus the results reveal the importance of independent measurements of cake resistance. (author)

  19. Numerical study of canister filters with alternatives filter cap configurations

    Science.gov (United States)

    Mohammed, A. N.; Daud, A. R.; Abdullah, K.; Seri, S. M.; Razali, M. A.; Hushim, M. F.; Khalid, A.

    2017-09-01

    Air filtration system and filter play an important role in getting a good quality air into turbo machinery such as gas turbine. The filtration system and filter has improved the quality of air and protect the gas turbine part from contaminants which could bring damage. During separation of contaminants from the air, pressure drop cannot be avoided but it can be minimized thus helps to reduce the intake losses of the engine [1]. This study is focused on the configuration of the filter in order to obtain the minimal pressure drop along the filter. The configuration used is the basic filter geometry provided by Salutary Avenue Manufacturing Sdn Bhd. and two modified canister filter cap which is designed based on the basic filter model. The geometries of the filter are generated by using SOLIDWORKS software and Computational Fluid Dynamics (CFD) software is used to analyse and simulates the flow through the filter. In this study, the parameters of the inlet velocity are 0.032 m/s, 0.063 m/s, 0.094 m/s and 0.126 m/s. The total pressure drop produce by basic, modified filter 1 and 2 is 292.3 Pa, 251.11 Pa and 274.7 Pa. The pressure drop reduction for the modified filter 1 is 41.19 Pa and 14.1% lower compared to basic filter and the pressure drop reduction for modified filter 2 is 17.6 Pa and 6.02% lower compared to the basic filter. The pressure drops for the basic filter are slightly different with the Salutary Avenue filter due to limited data and experiment details. CFD software are very reliable in running a simulation rather than produces the prototypes and conduct the experiment thus reducing overall time and cost in this study.

  20. Generalized Selection Weighted Vector Filters

    Directory of Open Access Journals (Sweden)

    Rastislav Lukac

    2004-09-01

    Full Text Available This paper introduces a class of nonlinear multichannel filters capable of removing impulsive noise in color images. The here-proposed generalized selection weighted vector filter class constitutes a powerful filtering framework for multichannel signal processing. Previously defined multichannel filters such as vector median filter, basic vector directional filter, directional-distance filter, weighted vector median filters, and weighted vector directional filters are treated from a global viewpoint using the proposed framework. Robust order-statistic concepts and increased degree of freedom in filter design make the proposed method attractive for a variety of applications. Introduced multichannel sigmoidal adaptation of the filter parameters and its modifications allow to accommodate the filter parameters to varying signal and noise statistics. Simulation studies reported in this paper indicate that the proposed filter class is computationally attractive, yields excellent performance, and is able to preserve fine details and color information while efficiently suppressing impulsive noise. This paper is an extended version of the paper by Lukac et al. presented at the 2003 IEEE-EURASIP Workshop on Nonlinear Signal and Image Processing (NSIP '03 in Grado, Italy.

  1. Effects of SiC and MgO on aluminabased ceramic foams filters

    OpenAIRE

    CAO Da-li; ZHOU Jing-yi; JIN Yong-ming

    2007-01-01

    Alumina-based foam ceramic filters were fabricated by using alumina, SiC, magnesia powder as major materials. It has been found that this ceramic filter has a uniform macrostructure for filtering molten metals. The influences of SiC and magnesia content, the sintering temperatures on ceramic properties were discussed. Aluminabased foam ceramic filters containing 2.2 mass% magnesia and 7.6 mass% SiC has a compressive strength of 1.36 MPa and a thermal shock resistance of 5 times. Its main phas...

  2. Preparation and characterization of monel (70% Ni-30% Cu) metallic filters

    International Nuclear Information System (INIS)

    Camargo Lavos, I. de.

    1993-01-01

    This work investigates a process for the fabrication and characterization of monel (Ni-Cu) filters. The powder consolidation was made by vibration or by pressing at various pressures (200, 300 e 400 MPa). The sintering was carried out at 1100 0 C during 1 hour under H 2 atmosphere. The filter characterization was performed by measuring its density, porosity, filtering capacity and permeability. It was obtained a correlation between the processing variables (consolidation and sintering), including powder properties, and the filters characteristics. (author). 59 refs, 41 figs, 7 tabs

  3. Effects of SiC and MgO on aluminabased ceramic foams filters

    Directory of Open Access Journals (Sweden)

    CAO Da-li

    2007-11-01

    Full Text Available Alumina-based foam ceramic filters were fabricated by using alumina, SiC, magnesia powder as major materials. It has been found that this ceramic filter has a uniform macrostructure for filtering molten metals. The influences of SiC and magnesia content, the sintering temperatures on ceramic properties were discussed. Aluminabased foam ceramic filters containing 2.2 mass% magnesia and 7.6 mass% SiC has a compressive strength of 1.36 MPa and a thermal shock resistance of 5 times. Its main phases after 1 hour sintering at 1 500 consist of alumina, silicon carbide, spinel and mullite.

  4. ReaxFF molecular dynamics simulation of intermolecular structure formation in acetic acid-water mixtures at elevated temperatures and pressures

    Science.gov (United States)

    Sengul, Mert Y.; Randall, Clive A.; van Duin, Adri C. T.

    2018-04-01

    The intermolecular structure formation in liquid and supercritical acetic acid-water mixtures was investigated using ReaxFF-based molecular dynamics simulations. The microscopic structures of acetic acid-water mixtures with different acetic acid mole fractions (1.0 ≥ xHAc ≥ 0.2) at ambient and critical conditions were examined. The potential energy surface associated with the dissociation of acetic acid molecules was calculated using a metadynamics procedure to optimize the dissociation energy of ReaxFF potential. At ambient conditions, depending on the acetic acid concentration, either acetic acid clusters or water clusters are dominant in the liquid mixture. When acetic acid is dominant (0.4 ≤ xHAc), cyclic dimers and chain structures between acetic acid molecules are present in the mixture. Both structures disappear at increased water content of the mixture. It was found by simulations that the acetic acid molecules released from these dimer and chain structures tend to stay in a dipole-dipole interaction. These structural changes are in agreement with the experimental results. When switched to critical conditions, the long-range interactions (e.g., second or fourth neighbor) disappear and the water-water and acetic acid-acetic acid structural formations become disordered. The simulated radial distribution function for water-water interactions is in agreement with experimental and computational studies. The first neighbor interactions between acetic acid and water molecules are preserved at relatively lower temperatures of the critical region. As higher temperatures are reached in the critical region, these interactions were observed to weaken. These simulations indicate that ReaxFF molecular dynamics simulations are an appropriate tool for studying supercritical water/organic acid mixtures.

  5. A Differential Geometric Approach to Nonlinear Filtering: The Projection Filter

    NARCIS (Netherlands)

    Brigo, D.; Hanzon, B.; LeGland, F.

    1998-01-01

    This paper presents a new and systematic method of approximating exact nonlinear filters with finite dimensional filters, using the differential geometric approach to statistics. The projection filter is defined rigorously in the case of exponential families. A convenient exponential family is

  6. Fabric based supercapacitor

    International Nuclear Information System (INIS)

    Yong, S; Tudor, M J; Beeby, S P; Owen, J R

    2013-01-01

    Flexible supercapacitors with electrodes coated on inexpensive fabrics by the dipping technique. This paper present details of the design, fabrication and characterisation of fabric supercapacitor. The sandwich structured supercapacitors can achieve specific capacitances of 11.1F/g, area capacitance 105 mF.cm −2 and maintain 95% of the initial capacitance after cycling the device for more than 15000 times

  7. Turbidity and microbes removal from water using an electrochemical filter

    International Nuclear Information System (INIS)

    Venkateswaran, G.; Gokhale, B.K.; Belapurkar, A.D.; Kumbhar, A.G.; Balaji, V.

    2004-01-01

    An in-house designed and fabricated Electrochemical fibrous graphite filter (ECF) was used to remove turbidity and microbes. The filter was found to be effective in removing sub micron size indium turbidity from RAPS-1 moderator water, iron turbidity from Active Process Cooling Water (APCW) of Kaiga Generating Station and microbial reduction from process cooling water RAPS-2. Unlike conventional turbidity removal by addition of coagulants and biocide chemical additions for purification, ECF is a clean way to remove the turbidity without contaminating the system and is best suited for close loop systems

  8. Analog filters in nanometer CMOS

    CERN Document Server

    Uhrmann, Heimo; Zimmermann, Horst

    2014-01-01

    Starting from the basics of analog filters and the poor transistor characteristics in nanometer CMOS 10 high-performance analog filters developed by the authors in 120 nm and 65 nm CMOS are described extensively. Among them are gm-C filters, current-mode filters, and active filters for system-on-chip realization for Bluetooth, WCDMA, UWB, DVB-H, and LTE applications. For the active filters several operational amplifier designs are described. The book, furthermore, contains a review of the newest state of research on low-voltage low-power analog filters. To cover the topic of the book comprehensively, linearization issues and measurement methods for the characterization of advanced analog filters are introduced in addition. Numerous elaborate illustrations promote an easy comprehension. This book will be of value to engineers and researchers in industry as well as scientists and Ph.D students at universities. The book is also recommendable to graduate students specializing on nanoelectronics, microelectronics ...

  9. The General Amino Acid Permease FfGap1 of Fusarium fujikuroi Is Sorted to the Vacuole in a Nitrogen-Dependent, but Npr1 Kinase-Independent Manner.

    Directory of Open Access Journals (Sweden)

    Andreas Pfannmüller

    Full Text Available The rice pathogenic fungus Fusarium fujikuroi is well known for the production of a broad spectrum of secondary metabolites (SMs such as gibberellic acids (GAs, mycotoxins and pigments. The biosynthesis of most of these SMs strictly depends on nitrogen availability and of the activity of permeases of nitrogen sources, e.g. the ammonium and amino acid permeases. One of the three ammonium permeases, MepB, was recently shown to act not only as a transporter but also as a nitrogen sensor affecting the production of nitrogen-repressed SMs. Here we describe the identification of a general amino acid permease, FfGap1, among the 99 putative amino acid permeases (AAPs in the genome of F. fujikuroi. FfGap1 is able to fully restore growth of the yeast gap1∆ mutant on several amino acids including citrulline and tryptophane. In S. cerevisiae, Gap1 activity is regulated by shuttling between the plasma membrane (nitrogen limiting conditions and the vacuole (nitrogen sufficiency, which we also show for FfGap1. In yeast, the Npr1 serine/threonine kinase stabilizes the Gap1 position at the plasma membrane. Here, we identified and characterized three NPR1-homologous genes, encoding the putative protein kinases FfNpr1-1, FfNpr1-2 and FfNpr1-3 with significant similarity to yeast Npr1. Complementation of the yeast npr1Δ mutant with each of the three F. fujikuroi NPR1 homologues, resulted in partial restoration of ammonium, arginine and proline uptake by FfNPR1-1 while none of the three kinases affect growth on different nitrogen sources and nitrogen-dependent sorting of FfGap1 in F. fujikuroi. However, exchange of the putative ubiquitin-target lysine 9 (K9A and 15 (K15A residues of FfGap1 resulted in extended localization to the plasma membrane and increased protein stability independently of nitrogen availability. These data suggest a similar regulation of FfGap1 by nitrogen-dependent ubiquitination, but differences regarding the role of Fusarium Npr1

  10. Improvement of the penumbra for small radiosurgical fields using flattening filter free low megavoltage beams

    Energy Technology Data Exchange (ETDEWEB)

    Yarahmadi, Mehran [Kurdistan Univ. of Medical Sciences, Sanandaj (Iran, Islamic Republic of); Allahverdi, Mahmoud; Nedaie, Hassan A.; Asnaashari, Khadijeh; Vaezzadeh, Sayed A. [Tehran Univ. of Medical Sciences, Tehran (Iran, Islamic Republic of); Sauer, Otto A. [Wuerzburg Univ. (Germany). Klinik und Poliklinik fuer Strahlentherapie

    2013-07-01

    Background: In stereotactic radiosurgery, sharp beam edges have clear advantages to spare normal tissues. In general, the dose gradient is a limiting factor in minimizing dose to nearby critical structures for clinical cases. Therefore the penumbral width should be diminished. Methods: A Varian Clinac 2100 linear accelerator equipped with in-house designed radiosurgical collimator was modeled using the EGSnrc/BEAMnrc Monte Carlo code and compared with the measurements. The 0.015 cm{sup 3} PinPoint chamber was used to measure the 6 MV photon beam characteristics and to validate Monte Carlo calculations. Additional to the standard (STD) linac, a flattening filter free (FFF) linac was simulated. Percent depth doses, beam profiles and output factors were calculated for small field sizes with diameter of 5, 10, 20 and 30 mm with DOSXYZnrc. The mean energy and photon fluence at the water surface were calculated with BEAMDP for both FFF linac and STD linacs. Results: The penumbra width (80%-20%) was decreased by 0.5, 0.3, 0.2 and 0.2 mm for field sizes of 5, 10, 20 and 30 mm respectively when removing the FF. The fluence of photons at the surface increased up to 3.6 times and the mean energy decreased by a factor of 0.69 when removing the FF. The penumbra width (80%-20%) decreased by 17% when a 2 MeV monoenergetic electron pencil beam incident on the target is used instead of 6.2 MeV. Conclusions: It was found that the penumbra of small field sizes is decreased by removing the FF. Likewise using low megavoltage photons reduced the beam penumbra maintaining adequate penetration and skin sparing. (orig.)

  11. Shifted-modified Chebyshev filters

    OpenAIRE

    ŞENGÜL, Metin

    2013-01-01

    This paper introduces a new type of filter approximation method that utilizes shifted-modified Chebyshev filters. Construction of the new filters involves the use of shifted-modified Chebyshev polynomials that are formed using the roots of conventional Chebyshev polynomials. The study also includes 2 tables containing the shifted-modified Chebyshev polynomials and the normalized element values for the low-pass prototype filters up to degree 6. The transducer power gain, group dela...

  12. The magnetic centrifugal mass filter

    International Nuclear Information System (INIS)

    Fetterman, Abraham J.; Fisch, Nathaniel J.

    2011-01-01

    Mass filters using rotating plasmas have been considered for separating nuclear waste and spent nuclear fuel. We propose a new mass filter that utilizes centrifugal and magnetic confinement of ions in a way similar to the asymmetric centrifugal trap. This magnetic centrifugal mass filter is shown to be more proliferation resistant than present technology. This filter is collisional and produces well confined output streams, among other advantages.

  13. The magnetic centrifugal mass filter

    Energy Technology Data Exchange (ETDEWEB)

    Fetterman, Abraham J.; Fisch, Nathaniel J. [Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540 (United States)

    2011-09-15

    Mass filters using rotating plasmas have been considered for separating nuclear waste and spent nuclear fuel. We propose a new mass filter that utilizes centrifugal and magnetic confinement of ions in a way similar to the asymmetric centrifugal trap. This magnetic centrifugal mass filter is shown to be more proliferation resistant than present technology. This filter is collisional and produces well confined output streams, among other advantages.

  14. Monte Carlo study of in-field and out-of-field dose distributions from a linear accelerator operating with and without a flattening-filter

    International Nuclear Information System (INIS)

    Almberg, S. S.; Frengen, J.; Lindmo, T.

    2012-01-01

    Purpose: To compare dosimetric characteristics of 6 MV photon fields originating from a linear accelerator operating with (FF) and without (FFF) a flattening-filter. The main objective is to establish a FFF model that results in similar depth-dose and build-up profiles as the original FF model, and subsequently estimate and compare out-of-field dose distributions. Methods: The EGSnrc Monte Carlo user codes BEAMnrc and DOSXYZnrc are used for photon beam simulations of an Elekta linear accelerator and dose calculations in a water phantom, respectively. Three beam models were analyzed: (1) the conventional linear accelerator with the flattening-filter in place and incident electron energy 6.45 MeV (FF 6.45 MeV), (2) similar flattening-filter-free model (FFF 6.45 MeV), and (3) as (2) but with increased electron energy (FFF 8.0 MeV). The field size 5 × 5 cm 2 was used for characterization of dose output, depth dose profiles, and photon spectrum. The field size 40 × 40 cm 2 was used for characterization of cross-field photon energy, photon fluence, and dose distributions. Out-of-field dose distributions were analyzed in both in-plane and cross-plane directions for 5 × 5 cm 2 and 10 × 10 cm 2 fields. Results: Comparable depth dose distributions, including the build-up region, for FF and FFF fields were achieved by increasing the electron energy from 6.45 MeV to 8.0 MeV for the FFF beam. The FFF beams result in reduced out-of-field dose compared to the FF beam: the reduction was most apparent in the cross-plane direction and more pronounced by the FFF 8.0 MeV beam compared to the FFF 6.45 MeV beam. Differences in out-of-field dose due to direction (in-plane vs cross-plane) were up to 40% for the FF beam; this effect was significantly reduced for the FFF beams. As the flattening-filter is a major source of contaminating electrons, superficial out-of-field dose was expected, and was found to be, reduced for FFF beams. Conclusions: The build-up and depth

  15. Monte Carlo study of in-field and out-of-field dose distributions from a linear accelerator operating with and without a flattening-filter.

    Science.gov (United States)

    Almberg, S S; Frengen, J; Lindmo, T

    2012-08-01

    To compare dosimetric characteristics of 6 MV photon fields originating from a linear accelerator operating with (FF) and without (FFF) a flattening-filter. The main objective is to establish a FFF model that results in similar depth-dose and build-up profiles as the original FF model, and subsequently estimate and compare out-of-field dose distributions. The EGSnrc Monte Carlo user codes BEAMnrc and DOSXYZnrc are used for photon beam simulations of an Elekta linear accelerator and dose calculations in a water phantom, respectively. Three beam models were analyzed: (1) the conventional linear accelerator with the flattening-filter in place and incident electron energy 6.45 MeV (FF 6.45 MeV), (2) similar flattening-filter-free model (FFF 6.45 MeV), and (3) as (2) but with increased electron energy (FFF 8.0 MeV). The field size 5 × 5 cm(2) was used for characterization of dose output, depth dose profiles, and photon spectrum. The field size 40 × 40 cm(2) was used for characterization of cross-field photon energy, photon fluence, and dose distributions. Out-of-field dose distributions were analyzed in both in-plane and cross-plane directions for 5 × 5 cm(2) and 10 × 10 cm(2) fields. Comparable depth dose distributions, including the build-up region, for FF and FFF fields were achieved by increasing the electron energy from 6.45 MeV to 8.0 MeV for the FFF beam. The FFF beams result in reduced out-of-field dose compared to the FF beam: the reduction was most apparent in the cross-plane direction and more pronounced by the FFF 8.0 MeV beam compared to the FFF 6.45 MeV beam. Differences in out-of-field dose due to direction (in-plane vs cross-plane) were up to 40% for the FF beam; this effect was significantly reduced for the FFF beams. As the flattening-filter is a major source of contaminating electrons, superficial out-of-field dose was expected, and was found to be, reduced for FFF beams. The build-up and depth-dose characteristics of a conventional "6 MV" beam

  16. Stochastic stacking without filters

    International Nuclear Information System (INIS)

    Johnson, R.P.; Marriner, J.

    1982-12-01

    The rate of accumulation of antiprotons is a critical factor in the design of p anti p colliders. A design of a system to accumulate higher anti p fluxes is presented here which is an alternative to the schemes used at the CERN AA and in the Fermilab Tevatron I design. Contrary to these stacking schemes, which use a system of notch filters to protect the dense core of antiprotons from the high power of the stack tail stochastic cooling, an eddy current shutter is used to protect the core in the region of the stack tail cooling kicker. Without filters one can have larger cooling bandwidths, better mixing for stochastic cooling, and easier operational criteria for the power amplifiers. In the case considered here a flux of 1.4 x 10 8 per sec is achieved with a 4 to 8 GHz bandwidth

  17. Multilevel particle filter

    KAUST Repository

    Law, Kody

    2016-01-06

    This talk will pertain to the filtering of partially observed diffusions, with discrete-time observations. It is assumed that only biased approximations of the diffusion can be obtained, for choice of an accuracy parameter indexed by l. A multilevel estimator is proposed, consisting of a telescopic sum of increment estimators associated to the successive levels. The work associated to O( 2) mean-square error between the multilevel estimator and average with respect to the filtering distribution is shown to scale optimally, for example as O( 2) for optimal rates of convergence of the underlying diffusion approximation. The method is illustrated on some toy examples as well as estimation of interest rate based on real S&P 500 stock price data.

  18. Filtered cathodic arc source

    International Nuclear Information System (INIS)

    Falabella, S.; Sanders, D.M.

    1994-01-01

    A continuous, cathodic arc ion source coupled to a macro-particle filter capable of separation or elimination of macro-particles from the ion flux produced by cathodic arc discharge is described. The ion source employs an axial magnetic field on a cathode (target) having tapered sides to confine the arc, thereby providing high target material utilization. A bent magnetic field is used to guide the metal ions from the target to the part to be coated. The macro-particle filter consists of two straight solenoids, end to end, but placed at 45 degree to one another, which prevents line-of-sight from the arc spot on the target to the parts to be coated, yet provides a path for ions and electrons to flow, and includes a series of baffles for trapping the macro-particles. 3 figures

  19. The Rao-Blackwellized Particle Filter: A Filter Bank Implementation

    Directory of Open Access Journals (Sweden)

    Karlsson Rickard

    2010-01-01

    Full Text Available For computational efficiency, it is important to utilize model structure in particle filtering. One of the most important cases occurs when there exists a linear Gaussian substructure, which can be efficiently handled by Kalman filters. This is the standard formulation of the Rao-Blackwellized particle filter (RBPF. This contribution suggests an alternative formulation of this well-known result that facilitates reuse of standard filtering components and which is also suitable for object-oriented programming. Our RBPF formulation can be seen as a Kalman filter bank with stochastic branching and pruning.

  20. Manipulation Robustness of Collaborative Filtering

    OpenAIRE

    Benjamin Van Roy; Xiang Yan

    2010-01-01

    A collaborative filtering system recommends to users products that similar users like. Collaborative filtering systems influence purchase decisions and hence have become targets of manipulation by unscrupulous vendors. We demonstrate that nearest neighbors algorithms, which are widely used in commercial systems, are highly susceptible to manipulation and introduce new collaborative filtering algorithms that are relatively robust.

  1. Quick-change filter cartridge

    Science.gov (United States)

    Rodgers, John C.; McFarland, Andrew R.; Ortiz, Carlos A.

    1995-01-01

    A quick-change filter cartridge. In sampling systems for measurement of airborne materials, a filter element is introduced into the sampled airstream such that the aerosol constituents are removed and deposited on the filter. Fragile sampling media often require support in order to prevent rupture during sampling, and careful mounting and sealing to prevent misalignment, tearing, or creasing which would allow the sampled air to bypass the filter. Additionally, handling of filter elements may introduce cross-contamination or exposure of operators to toxic materials. Moreover, it is desirable to enable the preloading of filter media into quick-change cartridges in clean laboratory environments, thereby simplifying and expediting the filter-changing process in the field. The quick-change filter cartridge of the present invention permits the application of a variety of filter media in many types of instruments and may also be used in automated systems. The cartridge includes a base through which a vacuum can be applied to draw air through the filter medium which is located on a porous filter support and held there by means of a cap which forms an airtight seal with the base. The base is also adapted for receiving absorbing media so that both particulates and gas-phase samples may be trapped for investigation, the latter downstream of the aerosol filter.

  2. Filter Effectiveness Evaluation

    Science.gov (United States)

    2013-08-01

    synthetic paraffinic kerosene (SPK), as well as Ultra Low Sulfur Diesel (ULSD) treated with mono-olein to simulate the effects of biodiesel . Results...fuel. Sufficient analysis and qualification of filter products is becoming increasingly crucial in ground transportation vehicles to promote the...well as a simulated biodiesel composed of ultra low sulfur diesel (ULSD) and mono-olein. As written in the scope of work, the alternative aviation

  3. Matched-Filter Thermography

    Directory of Open Access Journals (Sweden)

    Nima Tabatabaei

    2018-04-01

    Full Text Available Conventional infrared thermography techniques, including pulsed and lock-in thermography, have shown great potential for non-destructive evaluation of broad spectrum of materials, spanning from metals to polymers to biological tissues. However, performance of these techniques is often limited due to the diffuse nature of thermal wave fields, resulting in an inherent compromise between inspection depth and depth resolution. Recently, matched-filter thermography has been introduced as a means for overcoming this classic limitation to enable depth-resolved subsurface thermal imaging and improving axial/depth resolution. This paper reviews the basic principles and experimental results of matched-filter thermography: first, mathematical and signal processing concepts related to matched-fileting and pulse compression are discussed. Next, theoretical modeling of thermal-wave responses to matched-filter thermography using two categories of pulse compression techniques (linear frequency modulation and binary phase coding are reviewed. Key experimental results from literature demonstrating the maintenance of axial resolution while inspecting deep into opaque and turbid media are also presented and discussed. Finally, the concept of thermal coherence tomography for deconvolution of thermal responses of axially superposed sources and creation of depth-selective images in a diffusion-wave field is reviewed.

  4. Controlling flow conditions of test filters in iodine filters

    International Nuclear Information System (INIS)

    Holmberg, R.; Laine, J.

    1979-03-01

    Several different iodine filter and test filter designs and experience gained from their operation are presented. For the flow experiments, an iodine filter system equipped with flow regulating and measuring devices was built. In the experiments the influence of the packing method of the iodine sorption material and the influence of the flow regulating and measuring divices upon the flow conditions in the test filters was studied. On the basis of the experiments it has been shown that the flows through the test filters always can be adjusted to a correct value if there only is a high enough pressure difference available across the test filter ducting. As a result of the research, several different methods are presented with which the flows through the test filters in both operating and future iodine sorption system can easily be measured and adjusted to their correct values. (author)

  5. Mixed logic style adder circuit designed and fabricated using SOI substrate for irradiation-hardened experiment

    Science.gov (United States)

    Yuan, Shoucai; Liu, Yamei

    2016-08-01

    This paper proposed a rail to rail swing, mixed logic style 28-transistor 1-bit full adder circuit which is designed and fabricated using silicon-on-insulator (SOI) substrate with 90 nm gate length technology. The main goal of our design is space application where circuits may be damaged by outer space radiation; so the irradiation-hardened technique such as SOI structure should be used. The circuit's delay, power and power-delay product (PDP) of our proposed gate diffusion input (GDI)-based adder are HSPICE simulated and compared with other reported high-performance 1-bit adder. The GDI-based 1-bit adder has 21.61% improvement in delay and 18.85% improvement in PDP, over the reported 1-bit adder. However, its power dissipation is larger than that reported with 3.56% increased but is still comparable. The worst case performance of proposed 1-bit adder circuit is also seen to be less sensitive to variations in power supply voltage (VDD) and capacitance load (CL), over a wide range from 0.6 to 1.8 V and 0 to 200 fF, respectively. The proposed and reported 1-bit full adders are all layout designed and wafer fabricated with other circuits/systems together on one chip. The chip measurement and analysis has been done at VDD = 1.2 V, CL = 20 fF, and 200 MHz maximum input signal frequency with temperature of 300 K.

  6. Optimum color filters for CCD digital cameras

    Science.gov (United States)

    Engelhardt, Kai; Kunz, Rino E.; Seitz, Peter; Brunner, Harald; Knop, Karl

    1993-12-01

    As part of the ESPRIT II project No. 2103 (MASCOT) a high performance prototype color CCD still video camera was developed. Intended for professional usage such as in the graphic arts, the camera provides a maximum resolution of 3k X 3k full color pixels. A high colorimetric performance was achieved through specially designed dielectric filters and optimized matrixing. The color transformation was obtained by computer simulation of the camera system and non-linear optimization which minimized the perceivable color errors as measured in the 1976 CIELUV uniform color space for a set of about 200 carefully selected test colors. The color filters were designed to allow perfect colorimetric reproduction in principle and at the same time with imperceptible color noise and with special attention to fabrication tolerances. The camera system includes a special real-time digital color processor which carries out the color transformation. The transformation can be selected from a set of sixteen matrices optimized for different illuminants and output devices. Because the actual filter design was based on slightly incorrect data the prototype camera showed a mean colorimetric error of 2.7 j.n.d. (CIELUV) in experiments. Using correct input data in the redesign of the filters, a mean colorimetric error of only 1 j.n.d. (CIELUV) seems to be feasible, implying that it is possible with such an optimized color camera to achieve such a high colorimetric performance that the reproduced colors in an image cannot be distinguished from the original colors in a scene, even in direct comparison.

  7. Fabrics in Function

    DEFF Research Database (Denmark)

    Bang, Anne Louise

    2007-01-01

    sensing of fabrics in function. It is proposed that tactile and visual sensing of fabrics is a way to investigate and express emotional utility values. The further purpose is to use experiments with repertory grid models as part of the mapping of the entire research project and also as a basis...

  8. Fabricating architectural volume

    DEFF Research Database (Denmark)

    Feringa, Jelle; Søndergaard, Asbjørn

    2015-01-01

    The 2011 edition of Fabricate inspired a number of collaborations, this article seeks to highlight three of these. There is a common thread amongst the projects presented: sharing the ambition to close the rift between design and fabrication while incorporating structural design aspects early on...

  9. Smart Fabrics Technology Development

    Science.gov (United States)

    Simon, Cory; Potter, Elliott; Potter, Elliott; McCabe, Mary; Baggerman, Clint

    2010-01-01

    Advances in Smart Fabrics technology are enabling an exciting array of new applications for NASA exploration missions, the biomedical community, and consumer electronics. This report summarizes the findings of a brief investigation into the state of the art and potential applications of smart fabrics to address challenges in human spaceflight.

  10. Reflection color filters of the three primary colors with wide viewing angles using common-thickness silicon subwavelength gratings.

    Science.gov (United States)

    Kanamori, Yoshiaki; Ozaki, Toshikazu; Hane, Kazuhiro

    2014-10-20

    We fabricated reflection color filters of the three primary colors with wide viewing angles using silicon two-dimensional subwavelength gratings on the same quartz substrate. The grating periods were 400, 340, and 300 nm for red, green, and blue filters, respectively. All of the color filters had the same grating thickness of 100 nm, which enabled simple fabrication of a color filter array. Reflected colors from the red, green, and blue filters under s-polarized white-light irradiation appeared in the respective colors at incident angles from 0 to 50°. By rigorous coupled-wave analysis, the dimensions of each color filter were designed, and the calculated reflectivity was compared with the measured reflectivity.

  11. The history of ceramic filters.

    Science.gov (United States)

    Fujishima, S

    2000-01-01

    The history of ceramic filters is surveyed. Included is the history of piezoelectric ceramics. Ceramic filters were developed using technology similar to that of quartz crystal and electro-mechanical filters. However, the key to this development involved the theoretical analysis of vibration modes and material improvements of piezoelectric ceramics. The primary application of ceramic filters has been for consumer-market use. Accordingly, a major emphasis has involved mass production technology, leading to low-priced devices. A typical ceramic filter includes monolithic resonators and capacitors packaged in unique configurations.

  12. Optics fabrication technical challenges

    International Nuclear Information System (INIS)

    Chabassier, G.; Ferriou, N.; Lavastre, E.; Maunier, C.; Neauport, J.; Taroux, D.; Balla, D.; Fornerod, J.C.

    2004-01-01

    Before the production of all the LMJ (MEGAJOULE laser) optics, the CEA had to proceed with the fabrication of about 300 large optics for the LIL (laser integration line) laser. Thanks to a fruitful collaboration with high-tech optics companies in Europe, this challenge has been successfully hit. In order to achieve the very tight requirements for cleanliness, laser damage threshold and all the other high demanding fabrication specifications, it has been necessary to develop and to set completely new fabrication process going and to build special outsize fabrication equipment. Through a couple of examples, this paper gives an overview of the work which has been done and shows some of the results which have been obtained: continuous laser glass melting, fabrication of the laser slabs, rapid-growth KDP (potassium dihydrogen phosphate) technology, large diffractive transmission gratings engraving and characterization. (authors)

  13. Applications of Molecular Dynamics, Monte Carlo and Metadynamics Simulations Using ReaxFF Reactive Force Fields to Fluid/Solid Interfaces

    Science.gov (United States)

    Raju, Muralikrishna

    The interaction of dense fluids (water, polar organic solvents, room temperature ionic liquids, etc.) with solid substrates controls many chemical processes encountered in nature and industry. The key features of fluid-solid interfaces (FSIs) are the high mobility and often reactivity of the fluid phase, and the structural control provided by the solid phase. In this dissertation we apply molecular modeling methods to study FSIs in the following systems: 1. Dissociation of water on titania surfaces. We studied the adsorption and dissociation of water at 300 K on the following TiO2 surfaces: anatase (101), (100), (112), (001) and rutile (110) at various water coverages, using a recently developed ReaxFF reactive force field. The molecular and dissociative adsorption configurations predicted by ReaxFF for various water coverages agree with previous theoretical studies and experiment. 2. Mechanisms of Oriented Attachment in TiO2 nanocrystals. Oriented attachment (OA) of nanocrystals is now widely recognized as a key process in the solution-phase growth of hierarchical nanostructures. However, the microscopic origins of OA remain unclear. Using the same ReaxFF Ti/O/H reactive force field employed in the previous study, we perform molecular dynamics simulations to study the aggregation of various titanium dioxide (anatase) nanocrystals in vacuum and humid environments. 3. Li interactions in carbon based materials. Graphitic carbon is still the most ubiquitously used anode material in Li-ion batteries. In spite of its ubiquity, there are few theoretical studies that fully capture the energetics and kinetics of Li in graphite and related nanostructures at experimentally relevant length/time-scales and Li-ion concentrations. In this study we describe development and application of a ReaxFF reactive force field to describe Li interactions in perfect and defective carbon based materials using atomistic simulations. We develop force-field parameters for Li-C systems using van

  14. Kaon Filtering For CLAS Data

    International Nuclear Information System (INIS)

    McNabb, J.

    2001-01-01

    The analysis of data from CLAS is a multi-step process. After the detectors for a given running period have been calibrated, the data is processed in the so called pass-1 cooking. During the pass-1 cooking each event is reconstructed by the program a1c which finds particle tracks and computes momenta from the raw data. The results are then passed on to several data monitoring and filtering utilities. In CLAS software, a filter is a parameterless function which returns an integer indicating whether an event should be kept by that filter or not. There is a main filter program called g1-filter which controls several specific filters and outputs several files, one for each filter. These files may then be analyzed separately, allowing individuals interested in one reaction channel to work from smaller files than using the whole data set would require. There are several constraints on what the filter functions should do. Obviously, the filtered files should be as small as possible, however the filter should also not reject any events that might be used in the later analysis for which the filter was intended

  15. Progress on the development of NbZr Radio frequency band reject filters

    International Nuclear Information System (INIS)

    Hudak, J.J.; Alper, M.; Cotte, D.; Gardner, C.G.; Harvey, A.

    1983-01-01

    This chapter reports on the design and testing of a tunable superconducting filter element fabricated from Nb25%Zr having a transition temperature of 11 K. The filter element will serve as a component in a multielement filter bank to be cooled to less than 10 K by a two stage Gifford-McMahon refrigerator. A radio frequency (RF) interference rejection system composed of a set of tunable superconducting filter elements is being developed to supplement conventional interference rejection tehcniques. The thermal loading performance of the 8.5 K Gifford-McMahon refrigerator is found to exceed 2 watts at 10 K on the second stage with a 10 watt loading on the first stage. A superconducting filter bank consisting of tunable narrow band RF filters applied to strong interfering signals can be used to match the dynamic range of the RF signal environment to that of the receiving system

  16. Neural Model for Left-Handed CPW Bandpass Filter Loaded Split Ring Resonator

    Science.gov (United States)

    Liu, Haiwen; Wang, Shuxin; Tan, Mingtao; Zhang, Qijun

    2010-02-01

    Compact left-handed coplanar waveguide (CPW) bandpass filter loaded split ring resonator (SRR) is presented in this paper. The proposed filter exhibits a quasi-elliptic function response and its circuit size occupies only 12 × 11.8 mm2 (≈0.21 λg × 0.20 λg). Also, a simple circuit model is given and the parametric study of this filter is discussed. Then, with the aid of NeuroModeler software, a five-layer feed-forward perceptron neural networks model is built up to optimize the proposed filter design fast and accurately. Finally, this newly left-handed CPW bandpass filter was fabricated and measured. A good agreement between simulations and measurement verifies the proposed left-handed filter and the validity of design methodology.

  17. Advanced photonic filters based on cascaded Sagnac loop reflector resonators in silicon-on-insulator nanowires

    Science.gov (United States)

    Wu, Jiayang; Moein, Tania; Xu, Xingyuan; Moss, David J.

    2018-04-01

    We demonstrate advanced integrated photonic filters in silicon-on-insulator (SOI) nanowires implemented by cascaded Sagnac loop reflector (CSLR) resonators. We investigate mode splitting in these standing-wave (SW) resonators and demonstrate its use for engineering the spectral profile of on-chip photonic filters. By changing the reflectivity of the Sagnac loop reflectors (SLRs) and the phase shifts along the connecting waveguides, we tailor mode splitting in the CSLR resonators to achieve a wide range of filter shapes for diverse applications including enhanced light trapping, flat-top filtering, Q factor enhancement, and signal reshaping. We present the theoretical designs and compare the CSLR resonators with three, four, and eight SLRs fabricated in SOI. We achieve versatile filter shapes in the measured transmission spectra via diverse mode splitting that agree well with theory. This work confirms the effectiveness of using CSLR resonators as integrated multi-functional SW filters for flexible spectral engineering.

  18. Advanced photonic filters based on cascaded Sagnac loop reflector resonators in silicon-on-insulator nanowires

    Directory of Open Access Journals (Sweden)

    Jiayang Wu

    2018-04-01

    Full Text Available We demonstrate advanced integrated photonic filters in silicon-on-insulator (SOI nanowires implemented by cascaded Sagnac loop reflector (CSLR resonators. We investigate mode splitting in these standing-wave (SW resonators and demonstrate its use for engineering the spectral profile of on-chip photonic filters. By changing the reflectivity of the Sagnac loop reflectors (SLRs and the phase shifts along the connecting waveguides, we tailor mode splitting in the CSLR resonators to achieve a wide range of filter shapes for diverse applications including enhanced light trapping, flat-top filtering, Q factor enhancement, and signal reshaping. We present the theoretical designs and compare the CSLR resonators with three, four, and eight SLRs fabricated in SOI. We achieve versatile filter shapes in the measured transmission spectra via diverse mode splitting that agree well with theory. This work confirms the effectiveness of using CSLR resonators as integrated multi-functional SW filters for flexible spectral engineering.

  19. OPTIMIZATION OF ADVANCED FILTER SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    R.A. Newby; G.J. Bruck; M.A. Alvin; T.E. Lippert

    1998-04-30

    Reliable, maintainable and cost effective hot gas particulate filter technology is critical to the successful commercialization of advanced, coal-fired power generation technologies, such as IGCC and PFBC. In pilot plant testing, the operating reliability of hot gas particulate filters have been periodically compromised by process issues, such as process upsets and difficult ash cake behavior (ash bridging and sintering), and by design issues, such as cantilevered filter elements damaged by ash bridging, or excessively close packing of filtering surfaces resulting in unacceptable pressure drop or filtering surface plugging. This test experience has focused the issues and has helped to define advanced hot gas filter design concepts that offer higher reliability. Westinghouse has identified two advanced ceramic barrier filter concepts that are configured to minimize the possibility of ash bridge formation and to be robust against ash bridges should they occur. The ''inverted candle filter system'' uses arrays of thin-walled, ceramic candle-type filter elements with inside-surface filtering, and contains the filter elements in metal enclosures for complete separation from ash bridges. The ''sheet filter system'' uses ceramic, flat plate filter elements supported from vertical pipe-header arrays that provide geometry that avoids the buildup of ash bridges and allows free fall of the back-pulse released filter cake. The Optimization of Advanced Filter Systems program is being conducted to evaluate these two advanced designs and to ultimately demonstrate one of the concepts in pilot scale. In the Base Contract program, the subject of this report, Westinghouse has developed conceptual designs of the two advanced ceramic barrier filter systems to assess their performance, availability and cost potential, and to identify technical issues that may hinder the commercialization of the technologies. A plan for the Option I, bench

  20. Nuclear fuel conversion and fabrication chemistry

    International Nuclear Information System (INIS)

    Lerch, R.E.; Norman, R.E.

    1984-01-01

    Following irradiation and reprocessing of nuclear fuel, two operations are performed to prepare the fuel for subsequent reuse as fuel: fuel conversion, and fuel fabrication. These operations complete the classical nuclear fuel cycle. Fuel conversion involves generating a solid form suitable for fabrication into nuclear fuel. For plutonium based fuels, either a pure PuO 2 material or a mixed PuO 2 -UO 2 fuel material is generated. Several methods are available for preparation of the pure PuO 2 including: oxalate or peroxide precipitation; or direct denitration. Once the pure PuO 2 is formed, it is fabricated into fuel by mechanically blending it with ceramic grade UO 2 . The UO 2 can be prepared by several methods which include direct denitration. ADU precipitation, AUC precipitation, and peroxide precipitation. Alternatively, UO 2 -PuO 2 can be generated directly using coprecipitation, direct co-denitration, or gel sphere processes. In coprecipitation, uranium and plutonium are either precipitated as ammonium diuranate and plutonium hydroxide or as a mixture of ammonium uranyl-plutonyl carbonate, filtered and dried. In direct thermal denitration, solutions of uranium and plutonium nitrates are heated causing concentration and, subsequently, direct denitration. In gel sphere conversion, solutions of uranium and plutonium nitrate containing additives are formed into spherical droplets, gelled, washed and dried. Refabrication of these UO 3 -PuO 2 starting materials is accomplished by calcination-reduction to UO 2 -PuO 2 followed by pellet fabrication. (orig.)

  1. Advances in Collaborative Filtering

    Science.gov (United States)

    Koren, Yehuda; Bell, Robert

    The collaborative filtering (CF) approach to recommenders has recently enjoyed much interest and progress. The fact that it played a central role within the recently completed Netflix competition has contributed to its popularity. This chapter surveys the recent progress in the field. Matrix factorization techniques, which became a first choice for implementing CF, are described together with recent innovations. We also describe several extensions that bring competitive accuracy into neighborhood methods, which used to dominate the field. The chapter demonstrates how to utilize temporal models and implicit feedback to extend models accuracy. In passing, we include detailed descriptions of some the central methods developed for tackling the challenge of the Netflix Prize competition.

  2. Adaptive projective filters

    International Nuclear Information System (INIS)

    Dikusar, N.D.

    1993-01-01

    The new approach to solving of the finding problem is proposed. The method is based on Discrete Projective Transformations (DPT), the List Square Fitting (LSF) and uses the information feedback in tracing for linear or quadratic track segments (TS). The fast and stable with respect to measurement errors and background points recurrent algorithm is suggested. The algorithm realizes the family of digital adaptive projective filters (APF) with known nonlinear weight functions-projective invariants. APF can be used in adequate control systems for collection, processing and compression of data, including tracking problems for the wide class of detectors. 10 refs.; 9 figs

  3. Multilevel ensemble Kalman filtering

    KAUST Repository

    Hoel, Hakon

    2016-06-14

    This work embeds a multilevel Monte Carlo sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF) in the setting of finite dimensional signal evolution and noisy discrete-time observations. The signal dynamics is assumed to be governed by a stochastic differential equation (SDE), and a hierarchy of time grids is introduced for multilevel numerical integration of that SDE. The resulting multilevel EnKF is proved to asymptotically outperform EnKF in terms of computational cost versus approximation accuracy. The theoretical results are illustrated numerically.

  4. Interdigital filter design

    CSIR Research Space (South Africa)

    Du Plessis, WP

    2009-10-01

    Full Text Available to the general inverter-coupled resonator bandpass filter structure in Figure 2 [6] by using the inverter shown in Figure 3. The admittance of the inverter in Figure 3 is 4 J= Y mn sin(βl) (1) where β is the propagation factor and l is the length... of the resonators (a quarter wavelength in this case). While the series quarter-wave line alone can approximate an inverter, the structure shown in Figure 3 is more accurate over wide bandwidths. At this point the circuits in Figures 1 and 2 still differ because...

  5. Multilevel ensemble Kalman filtering

    KAUST Repository

    Hoel, Hakon; Law, Kody J. H.; Tempone, Raul

    2016-01-01

    This work embeds a multilevel Monte Carlo sampling strategy into the Monte Carlo step of the ensemble Kalman filter (EnKF) in the setting of finite dimensional signal evolution and noisy discrete-time observations. The signal dynamics is assumed to be governed by a stochastic differential equation (SDE), and a hierarchy of time grids is introduced for multilevel numerical integration of that SDE. The resulting multilevel EnKF is proved to asymptotically outperform EnKF in terms of computational cost versus approximation accuracy. The theoretical results are illustrated numerically.

  6. Charcoal filter testing

    Energy Technology Data Exchange (ETDEWEB)

    Lyons, J. [Nuclear Regulatory Commission, Washington, DC (United States)

    1997-08-01

    In this very brief, informal presentation, a representative of the US Nuclear Regulatory Commission outlines some problems with charcoal filter testing procedures and actions being taken to correct the problems. Two primary concerns are addressed: (1) the process to find the test method is confusing, and (2) the requirements of the reference test procedures result in condensation on the charcoal and causes the test to fail. To address these problems, emergency technical specifications were processed for three nuclear plants. A generic or an administrative letter is proposed as a more permanent solution. 1 fig.

  7. Digital Filters for Low Frequency Equalization

    DEFF Research Database (Denmark)

    Tyril, Marni; Abildgaard, J.; Rubak, Per

    2001-01-01

    Digital filters with high resolution in the low-frequency range are studied. Specifically, for a given computational power, traditional IIR filters are compared with warped FIR filters, warped IIR filters, and modified warped FIR filters termed warped individual z FIR filters (WizFIR). The results...

  8. Effect of on-chip filter on Coulomb blockade thermometer

    International Nuclear Information System (INIS)

    Roschier, L; Penttilä, J S; Gunnarsson, D; Prunnila, M; Meschke, M; Savin, A

    2012-01-01

    Coulomb Blockade Thermometer (CBT) is a primary thermometer based on electric conductance of normal tunnel junction arrays. One limitation for CBT use at the lowest temperatures has been due to environmental noise heating. To improve on this limitation, we have done measurements on CBT sensors fabricated with different on-chip filtering structures in a dilution refrigerator with a base temperature of 10 mK. The CBT sensors were produced with a wafer scale tunnel junction process. We present how the different on-chip filtering schemes affect the limiting saturation temperatures and show that CBT sensors with proper on-chip filtering work at temperatures below 20 mK and are tolerant to noisy environment.

  9. Polymer filters for ultraviolet-excited integrated fluorescence sensing

    International Nuclear Information System (INIS)

    Dandin, Marc; Abshire, Pamela; Smela, Elisabeth

    2012-01-01

    Optical filters for blocking ultraviolet (UV) light were fabricated by doping various polymer hosts with a UV absorbing chromophore. The polymers were polydimethylsiloxane (PDMS), a silicone elastomer frequently used in microfluidics, SU-8, a photopatternable epoxy, and Humiseal 1B66, an acrylic coating used for moisture protection of integrated circuits. The chromophore was 2-(2′-hydroxy-5′-methylphenyl) benzotriazole (BTA), which has a high extinction coefficient between 300 nm and 400 nm. We demonstrate filters 5 µm thick that exhibit high ultraviolet rejection (nearly −40 dB at 342 nm) yet pass visible light (near 0 dB above 400 nm), making them ideal for ultraviolet-excited fluorescence sensing within microsystems. The absorbance of the BTA depended on the host polymer. These filters are promising for integrated fluorescence spectroscopy in bioanalytical platforms because they can be patterned by dry etching, molding or exposure to ultraviolet light. (paper)

  10. Fabrication and characterisation of fabric supercapacitor

    OpenAIRE

    Yong, Sheng

    2016-01-01

    Fabric supercapacitor is a flexible electrochemical device for energy storage application. It is designed to power up flexible electronic systems used for, for example, information sensing, data computation and communication. The development of a flexible supercapacitor is important for e-textiles since supercapacitor can achieve higher energy density than a standard parallel plate capacitor and a larger power density compared with a battery. This research area is currently facing barriers on...

  11. High flow ceramic pot filters.

    Science.gov (United States)

    van Halem, D; van der Laan, H; Soppe, A I A; Heijman, S G J

    2017-11-01

    Ceramic pot filters are considered safe, robust and appropriate technologies, but there is a general consensus that water revenues are limited due to clogging of the ceramic element. The objective of this study was to investigate the potential of high flow ceramic pot filters to produce more water without sacrificing their microbial removal efficacy. High flow pot filters, produced by increasing the rice husk content, had a higher initial flow rate (6-19 L h -1 ), but initial LRVs for E. coli of high flow filters was slightly lower than for regular ceramic pot filters. This disadvantage was, however, only temporarily as the clogging in high flow filters had a positive effect on the LRV for E. coli (from below 1 to 2-3 after clogging). Therefore, it can be carefully concluded that regular ceramic pot filters perform better initially, but after clogging, the high flow filters have a higher flow rate as well as a higher LRV for E. coli. To improve the initial performance of new high flow filters, it is recommended to further utilize residence time of the water in the receptacle, since additional E. coli inactivation was observed during overnight storage. Although a relationship was observed between flow rate and LRV of MS2 bacteriophages, both regular and high flow filters were unable to reach over 2 LRV. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Biodegradable microfabricated plug-filters for glaucoma drainage devices.

    Science.gov (United States)

    Maleki, Teimour; Chitnis, Girish; Park, Jun Hyeong; Cantor, Louis B; Ziaie, Babak

    2012-06-01

    We report on the development of a batch fabricated biodegradable truncated-cone-shaped plug filter to overcome the postoperative hypotony in nonvalved glaucoma drainage devices. Plug filters are composed of biodegradable polymers that disappear once wound healing and bleb formation has progressed past the stage where hypotony from overfiltration may cause complications in the human eye. The biodegradable nature of device eliminates the risks associated with permanent valves that may become blocked or influence the aqueous fluid flow rate in the long term. The plug-filter geometry simplifies its integration with commercial shunts. Aqueous humor outflow regulation is achieved by controlling the diameter of a laser-drilled through-hole. The batch compatible fabrication involves a modified SU-8 molding to achieve truncated-cone-shaped pillars, polydimethylsiloxane micromolding, and hot embossing of biodegradable polymers. The developed plug filter is 500 μm long with base and apex plane diameters of 500 and 300 μm, respectively, and incorporates a laser-drilled through-hole with 44-μm effective diameter in the center.

  13. Acoustic wave filter based on periodically poled lithium niobate.

    Science.gov (United States)

    Courjon, Emilie; Bassignot, Florent; Ulliac, Gwenn; Benchabane, Sarah; Ballandras, Sylvain

    2012-09-01

    Solutions for the development of compact RF passive transducers as an alternative to standard surface or bulk acoustic wave devices are receiving increasing interest. This article presents results on the development of an acoustic band-pass filter based on periodically poled ferroelectric domains in lithium niobate. The fabrication of periodically poled transducers (PPTs) operating in the range of 20 to 650 MHz has been achieved on 3-in (76.2-mm) 500-μm-thick wafers. This kind of transducer is able to excite elliptical as well as longitudinal modes, yielding phase velocities of about 3800 and 6500 ms(-1), respectively. A new type of acoustic band-pass filter is proposed, based on the use of PPTs instead of the SAWs excited by classical interdigital transducers. The design and the fabrication of such a filter are presented, as well as experimental measurements of its electrical response and transfer function. The feasibility of such a PPT-based filter is thereby demonstrated and the limitations of this method are discussed.

  14. Reduction of bonding resistance of two-terminal III-V/Si tandem solar cells fabricated using smart-stack technology

    Science.gov (United States)

    Baba, Masaaki; Makita, Kikuo; Mizuno, Hidenori; Takato, Hidetaka; Sugaya, Takeyoshi; Yamada, Noboru

    2017-12-01

    This paper describes a method that remarkably reduces the bonding resistance of mechanically stacked two-terminal GaAs/Si and InGaP/Si tandem solar cells, where the top and bottom cells are bonded using a Pd nanoparticle array. A transparent conductive oxide (TCO) layer, which partially covers the surface of the Si bottom cell below the electrodes of the III-V top cell, significantly enhances the fill factor (FF) and cell conversion efficiency. The partial TCO layer reduces the bonding resistance and thus, increases the FF and efficiency of InGaP/Si by factors of 1.20 and 1.11, respectively. Eventually, the efficiency exceeds 15%. Minimizing the optical losses at the bonding interfaces of the TCO layer is important in the fabrication of high-efficiency solar cells. To help facilitate this, the optical losses in the tandem solar cells are thoroughly characterized through optical simulations and experimental verifications.

  15. 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.

  16. Junction and circuit fabrication

    International Nuclear Information System (INIS)

    Jackel, L.D.

    1980-01-01

    Great strides have been made in Josephson junction fabrication in the four years since the first IC SQUID meeting. Advances in lithography have allowed the production of devices with planar dimensions as small as a few hundred angstroms. Improved technology has provided ultra-high sensitivity SQUIDS, high-efficiency low-noise mixers, and complex integrated circuits. This review highlights some of the new fabrication procedures. The review consists of three parts. Part 1 is a short summary of the requirements on junctions for various applications. Part 2 reviews intergrated circuit fabrication, including tunnel junction logic circuits made at IBM and Bell Labs, and microbridge radiation sources made at SUNY at Stony Brook. Part 3 describes new junction fabrication techniques, the major emphasis of this review. This part includes a discussion of small oxide-barrier tunnel junctions, semiconductor barrier junctions, and microbridge junctions. Part 3 concludes by considering very fine lithography and limitations to miniaturization. (orig.)

  17. Construction, fabrication, and installation

    International Nuclear Information System (INIS)

    1992-05-01

    This standard specifies the construction, fabrication, and installation requirements that apply to concrete containment structures of a containment system designated as class containment components, parts and appurtenances for nuclear power plants

  18. Experimental Fabrication Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Provides aviation fabrication support to special operations aircraft residing at Fort Eustis and other bases in the United States. Support is also provided to AATD...

  19. Alloy Fabrication Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — At NETL’s Alloy Fabrication Facility in Albany, OR, researchers conduct DOE research projects to produce new alloys suited to a variety of applications, from gas...

  20. Reconfigurable Mixed Mode Universal Filter

    Directory of Open Access Journals (Sweden)

    Neelofer Afzal

    2014-01-01

    Full Text Available This paper presents a novel mixed mode universal filter configuration capable of working in voltage and transimpedance mode. The proposed single filter configuration can be reconfigured digitally to realize all the five second order filter functions (types at single output port. Other salient features of proposed configuration include independently programmable filter parameters, full cascadability, and low sensitivity figure. However, all these features are provided at the cost of quite large number of active elements. It needs three digitally programmable current feedback amplifiers and three digitally programmable current conveyors. Use of six active elements is justified by introducing three additional reduced hardware mixed mode universal filter configurations and its comparison with reported filters.

  1. Fabricating nuclear components

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Activities of the Nuclear Engineering Division of Vickers Ltd., particularly fabrication of long slim tubular components for power reactors and the construction of irradiation loops and rigs, are outlined. The processes include hydraulic forming for fabrication of various types of tubes and outer cases of fuel transfer buckets, various specialised welding operations including some applications of the TIG process, and induction brazing of specialised assemblies. (U.K.)

  2. Nuclear Fabrication Consortium

    Energy Technology Data Exchange (ETDEWEB)

    Levesque, Stephen [EWI, Columbus, OH (United States)

    2013-04-05

    This report summarizes the activities undertaken by EWI while under contract from the Department of Energy (DOE) Office of Nuclear Energy (NE) for the management and operation of the Nuclear Fabrication Consortium (NFC). The NFC was established by EWI to independently develop, evaluate, and deploy fabrication approaches and data that support the re-establishment of the U.S. nuclear industry: ensuring that the supply chain will be competitive on a global stage, enabling more cost-effective and reliable nuclear power in a carbon constrained environment. The NFC provided a forum for member original equipment manufactures (OEM), fabricators, manufacturers, and materials suppliers to effectively engage with each other and rebuild the capacity of this supply chain by : Identifying and removing impediments to the implementation of new construction and fabrication techniques and approaches for nuclear equipment, including system components and nuclear plants. Providing and facilitating detailed scientific-based studies on new approaches and technologies that will have positive impacts on the cost of building of nuclear plants. Analyzing and disseminating information about future nuclear fabrication technologies and how they could impact the North American and the International Nuclear Marketplace. Facilitating dialog and initiate alignment among fabricators, owners, trade associations, and government agencies. Supporting industry in helping to create a larger qualified nuclear supplier network. Acting as an unbiased technology resource to evaluate, develop, and demonstrate new manufacturing technologies. Creating welder and inspector training programs to help enable the necessary workforce for the upcoming construction work. Serving as a focal point for technology, policy, and politically interested parties to share ideas and concepts associated with fabrication across the nuclear industry. The report the objectives and summaries of the Nuclear Fabrication Consortium

  3. DSP Control of Line Hybrid Active Filter

    DEFF Research Database (Denmark)

    Dan, Stan George; Benjamin, Doniga Daniel; Magureanu, R.

    2005-01-01

    Active Power Filters have been intensively explored in the past decade. Hybrid active filters inherit the efficiency of passive filters and the improved performance of active filters, and thus constitute a viable improved approach for harmonic compensation. In this paper a parallel hybrid filter...... is studied for current harmonic compensation. The hybrid filter is formed by a single tuned Le filter and a small-rated power active filter, which are directly connected in series without any matching transformer. Thus the required rating of the active filter is much smaller than a conventional standalone...... active filter. Simulation and experimental results obtained in laboratory confirmed the validity and effectiveness of the control....

  4. Multi-filter spectrophotometry simulations

    Science.gov (United States)

    Callaghan, Kim A. S.; Gibson, Brad K.; Hickson, Paul

    1993-01-01

    To complement both the multi-filter observations of quasar environments described in these proceedings, as well as the proposed UBC 2.7 m Liquid Mirror Telescope (LMT) redshift survey, we have initiated a program of simulated multi-filter spectrophotometry. The goal of this work, still very much in progress, is a better quantitative assessment of the multiband technique as a viable mechanism for obtaining useful redshift and morphological class information from large scale multi-filter surveys.

  5. Digital filtering in nuclear medicine

    International Nuclear Information System (INIS)

    Miller, T.R.; Sampathkumaran, S.

    1982-01-01

    Digital filtering is a powerful mathematical technique in computer analysis of nuclear medicine studies. The basic concepts of object-domain and frequency-domain filtering are presented in simple, largely nonmathemaical terms. Computational methods are described using both the Fourier transform and convolution techniques. The frequency response is described and used to represent the behavior of several classes of filters. These concepts are illustrated with examples drawn from a variety of important applications in nuclear medicine

  6. Hydrodynamics of microbial filter feeding.

    Science.gov (United States)

    Nielsen, Lasse Tor; Asadzadeh, Seyed Saeed; Dölger, Julia; Walther, Jens H; Kiørboe, Thomas; Andersen, Anders

    2017-08-29

    Microbial filter feeders are an important group of grazers, significant to the microbial loop, aquatic food webs, and biogeochemical cycling. Our understanding of microbial filter feeding is poor, and, importantly, it is unknown what force microbial filter feeders must generate to process adequate amounts of water. Also, the trade-off in the filter spacing remains unexplored, despite its simple formulation: A filter too coarse will allow suitably sized prey to pass unintercepted, whereas a filter too fine will cause strong flow resistance. We quantify the feeding flow of the filter-feeding choanoflagellate Diaphanoeca grandis using particle tracking, and demonstrate that the current understanding of microbial filter feeding is inconsistent with computational fluid dynamics (CFD) and analytical estimates. Both approaches underestimate observed filtration rates by more than an order of magnitude; the beating flagellum is simply unable to draw enough water through the fine filter. We find similar discrepancies for other choanoflagellate species, highlighting an apparent paradox. Our observations motivate us to suggest a radically different filtration mechanism that requires a flagellar vane (sheet), something notoriously difficult to visualize but sporadically observed in the related choanocytes (sponges). A CFD model with a flagellar vane correctly predicts the filtration rate of D. grandis , and using a simple model we can account for the filtration rates of other microbial filter feeders. We finally predict how optimum filter mesh size increases with cell size in microbial filter feeders, a prediction that accords very well with observations. We expect our results to be of significance for small-scale biophysics and trait-based ecological modeling.

  7. Box-particle intensity filter

    OpenAIRE

    Schikora, Marek; Gning, Amadou; Mihaylova, Lyudmila; Cremers, Daniel; Koch, Wofgang; Streit, Roy

    2012-01-01

    This paper develops a novel approach for multi-target tracking, called box-particle intensity filter (box-iFilter). The approach is able to cope with unknown clutter, false alarms and estimates the unknown number of targets. Furthermore, it is capable of dealing with three sources of uncertainty: stochastic, set-theoretic and data association uncertainty. The box-iFilter reduces the number of particles significantly, which improves the runtime considerably. The low particle number enables thi...

  8. Autoregressive Moving Average Graph Filtering

    OpenAIRE

    Isufi, Elvin; Loukas, Andreas; Simonetto, Andrea; Leus, Geert

    2016-01-01

    One of the cornerstones of the field of signal processing on graphs are graph filters, direct analogues of classical filters, but intended for signals defined on graphs. This work brings forth new insights on the distributed graph filtering problem. We design a family of autoregressive moving average (ARMA) recursions, which (i) are able to approximate any desired graph frequency response, and (ii) give exact solutions for tasks such as graph signal denoising and interpolation. The design phi...

  9. Faraday anomalous dispersion optical filters

    Science.gov (United States)

    Shay, T. M.; Yin, B.; Alvarez, L. S.

    1993-01-01

    The effect of Faraday anomalous dispersion optical filters on infrared and blue transitions of some alkali atoms is calculated. A composite system is designed to further increase the background noise rejection. The measured results of the solar background rejection and image quality through the filter are presented. The results show that the filter may provide high transmission and high background noise rejection with excellent image quality.

  10. Highly Sensitive Filter Paper Substrate for SERS Trace Explosives Detection

    Directory of Open Access Journals (Sweden)

    Pedro M. Fierro-Mercado

    2012-01-01

    Full Text Available We report on a novel and extremely low-cost surface-enhanced Raman spectroscopy (SERS substrate fabricated depositing gold nanoparticles on common lab filter paper using thermal inkjet technology. The paper-based substrate combines all advantages of other plasmonic structures fabricated by more elaborate techniques with the dynamic flexibility given by the inherent nature of the paper for an efficient sample collection, robustness, and stability. We describe the fabrication, characterization, and SERS activity of our substrate using 2,4,6-trinitrotoluene, 2,4-dinitrotoluene, and 1,3,5-trinitrobenzene as analytes. The paper-based SERS substrates presented a high sensitivity and excellent reproducibility for analytes employed, demonstrating a direct application in forensic science and homeland security.

  11. Electrospun Magnetic Nanoparticle-Decorated Nanofiber Filter and Its Applications to High-Efficiency Air Filtration.

    Science.gov (United States)

    Kim, Juyoung; Chan Hong, Seung; Bae, Gwi Nam; Jung, Jae Hee

    2017-10-17

    Filtration technology has been widely studied due to concerns about exposure to airborne dust, including metal oxide nanoparticles, which cause serious health problems. The aim of these studies has been to develop mechanisms for the continuous and efficient removal of metal oxide dusts. In this study, we introduce a novel air filtration system based on the magnetic attraction force. The filtration system is composed of a magnetic nanoparticle (MNP)-decorated nanofiber (MNP-NF) filter. Using a simple electrospinning system, we fabricated continuous and smooth electrospun nanofibers with evenly distributed Fe 3 O 4 MNPs. Our electrospun MNP-NF filter exhibited high particle collection efficiency (∼97% at 300 nm particle size) compared to the control filter (w/o MNPs, ∼ 68%), with a ∼ 64% lower pressure drop (∼17 Pa) than the control filter (∼27 Pa). Finally, the filter quality factors of the MNP-NF filter were 4.7 and 11.9 times larger than those of the control filter and the conventional high-efficiency particulate air filters (>99% and ∼269 Pa), respectively. Furthermore, we successfully performed a field test of our MNP-NF filter using dust from a subway station tunnel. This work suggests that our novel MNP-NF filter can be used to facilitate effective protection against hazardous metal oxide dust in real environments.

  12. A Codesigned Compact Dual-Band Filtering Antenna with PIN Loaded for WLAN Applications

    Directory of Open Access Journals (Sweden)

    Shanxiong Chen

    2014-01-01

    Full Text Available A codesigned compact dual-band filtering antenna incorporating a PIN diode for 2.45/5.2 GHz wireless local area network (WLAN applications is proposed in this paper. The integrated filtering antenna system consists of a simple monopole radiator, a microstrip dual-band band-pass filter, and a PIN diode. The performance of the filtering antenna is notably promoted by optimizing the impedance between the antenna and the band-pass filter, with good selectivity and out-of-band rejection. The design process follows the approach of the synthesis of band-pass filter. In addition, the PIN diode is incorporated in the filtering antenna for further size reduction, which also widens the coverage of the bandwidth by about 230% for 2.4 GHz WLAN. With the presence of small size and good filtering performances, the proposed filtering antenna is a good candidate for the wireless communication systems. Prototypes of the proposed filtering antenna incorporating a PIN diode are fabricated and measured. The measured results including return losses and radiation patterns are presented.

  13. Filters for water purification from radionuclides

    International Nuclear Information System (INIS)

    Mironov, V.V.; Khaydarov, R.R.; Khaydarov, R.A.; Gapurova, O.U.

    2006-01-01

    Full text: At present purification of waste water and drinking water from radionuclides, heavy metal ions, and organic contaminants is one of the most important problems. One of widely used methods for solving this problem is the ion exchange method based on using of different types of resins and fibroid sorbents. This paper deals with new chemically modified polyester fibroid filters having satisfactory adsorption characteristics. The process of the filter production includes their treatment by acrylonitrilic emulsion for improving mechanical characteristics. An advantage of the fibroid ion-exchange sorbents over resin is in their high sorption rate, effective regeneration and small value of pressure drop of the sorbent layer for purified water. The specific surface of the fibroid sorbents is (2 - 3). 10 4 m 2 / kg, i.e. about 10 2 times greater than that of the resin (10 2 m 2 / kg). Owing to that fact the rate of the sorption process on the developed fibroid sorbents is much greater than that on the resin. The developed cation- and anion-exchange filters can be used for removing metal ions (Zn, Ni, Cu, Sb, Co, Cd, Cr, etc.) and organic compounds (M- 32 P, M- 131 I, M- 99 Mo+ 99m Tc, etc.) from water. Capacity of the cation-exchange sorbents is 0.25 meq/g (Cu 2+ ) and that of the anion - exchange is 0.45 meq/g (Cr 6+ ). The cation- and anion-exchange filters are also selective for removing radionuclides 134 , 137 Cs, 90 Sr, 60 Co and 129 I in presence of Na + , K + , Ca 2+ , Mg 2+ , Cl - ions in water at concentrations up to 500 mg/L. New developed ion-exchange sorbents have been used in drinking water filters and mini-systems for removing organic and inorganic contaminants, in the equipment for waste water purification from oil products (at atomic power stations, car-washing stations, etc), from heavy metal ions (in electronic industry, match fabrics, leather processing plants etc). (author)

  14. Intelligent medical information filtering.

    Science.gov (United States)

    Quintana, Y

    1998-01-01

    This paper describes an intelligent information filtering system to assist users to be notified of updates to new and relevant medical information. Among the major problems users face is the large volume of medical information that is generated each day, and the need to filter and retrieve relevant information. The Internet has dramatically increased the amount of electronically accessible medical information and reduced the cost and time needed to publish. The opportunity of the Internet for the medical profession and consumers is to have more information to make decisions and this could potentially lead to better medical decisions and outcomes. However, without the assistance from professional medical librarians, retrieving new and relevant information from databases and the Internet remains a challenge. Many physicians do not have access to the services of a medical librarian. Most physicians indicate on surveys that they do not prefer to retrieve the literature themselves, or visit libraries because of the lack of recent materials, poor organisation and indexing of materials, lack of appropriate and available material, and lack of time. The information filtering system described in this paper records the online web browsing behaviour of each user and creates a user profile of the index terms found on the web pages visited by the user. A relevance-ranking algorithm then matches the user profiles to the index terms of new health care web pages that are added each day. The system creates customised summaries of new information for each user. A user can then connect to the web site to read the new information. Relevance feedback buttons on each page ask the user to rate the usefulness of the page to their immediate information needs. Errors in relevance ranking are reduced in this system by having both the user profile and medical information represented in the same representation language using a controlled vocabulary. This system also updates the user profiles

  15. Alternating current line-filter based on electrochemical capacitor utilizing template-patterned graphene

    OpenAIRE

    Zhenkun Wu; Liyi Li; Ziyin Lin; Bo Song; Zhuo Li; Kyoung-Sik Moon; Ching-Ping Wong; Shu-Lin Bai

    2015-01-01

    Aluminum electrolytic capacitors (AECs) are widely used for alternating current (ac) line-filtering. However, their bulky size is becoming more and more incompatible with the rapid development of portable electronics. Here we report a scalable process to fabricate miniaturized graphene-based ac line-filters on flexible substrates at room temperature. In this work, graphene oxide (GO) is reduced by patterned metal interdigits at room temperature and used directly as the electrode material. The...

  16. Full color organic light-emitting devices with microcavity structure and color filter.

    Science.gov (United States)

    Zhang, Weiwei; Liu, Hongyu; Sun, Runguang

    2009-05-11

    This letter demonstrated the fabrication of the full color passive matrix organic light-emitting devices based on the combination of the microcavity structure, color filter and a common white polymeric OLED. In the microcavity structure, patterned ITO terraces with different thickness were used as the anode as well as cavity spacer. The primary color emitting peaks were originally generated by the microcavity and then the second resonance peak was absorbed by the color filter.

  17. Device for filtering gaseous media

    International Nuclear Information System (INIS)

    Benzel, M.

    1978-01-01

    The air filter system for gaseous radioactive substances consists of a vertical chamber with filter material (charcoal, e.g. impregnated). On one side of the chamber there is an inlet compartment and an outlet compartment. On the other side a guiding compartment turns the gas flow coming from the natural-air side through the lower part of filter chamber to the upper part of the filter. The gas flow leaves the upper part through the outlet conpartment as cleaned-air flow. The filter material may be filled into the chamber from above and drawn off below. For better utilization of the filter material the filter chamber is separated by means of a wall between the inlet and outlet compartment. This partition wall consist of two sheets arranged one above the other provided with slots which may be superposed in alignment. In this case filter material is tickling from the upper part of the chamber into the lower part avoiding to form a crater in the filter bed. (DG) [de

  18. Adaptive filtering and change detection

    CERN Document Server

    Gustafsson, Fredrik

    2003-01-01

    Adaptive filtering is a classical branch of digital signal processing (DSP). Industrial interest in adaptive filtering grows continuously with the increase in computer performance that allows ever more conplex algorithms to be run in real-time. Change detection is a type of adaptive filtering for non-stationary signals and is also the basic tool in fault detection and diagnosis. Often considered as separate subjects Adaptive Filtering and Change Detection bridges a gap in the literature with a unified treatment of these areas, emphasizing that change detection is a natural extensi

  19. The intractable cigarette 'filter problem'.

    Science.gov (United States)

    Harris, Bradford

    2011-05-01

    When lung cancer fears emerged in the 1950s, cigarette companies initiated a shift in cigarette design from unfiltered to filtered cigarettes. Both the ineffectiveness of cigarette filters and the tobacco industry's misleading marketing of the benefits of filtered cigarettes have been well documented. However, during the 1950s and 1960s, American cigarette companies spent millions of dollars to solve what the industry identified as the 'filter problem'. These extensive filter research and development efforts suggest a phase of genuine optimism among cigarette designers that cigarette filters could be engineered to mitigate the health hazards of smoking. This paper explores the early history of cigarette filter research and development in order to elucidate why and when seemingly sincere filter engineering efforts devolved into manipulations in cigarette design to sustain cigarette marketing and mitigate consumers' concerns about the health consequences of smoking. Relevant word and phrase searches were conducted in the Legacy Tobacco Documents Library online database, Google Patents, and media and medical databases including ProQuest, JSTOR, Medline and PubMed. 13 tobacco industry documents were identified that track prominent developments involved in what the industry referred to as the 'filter problem'. These reveal a period of intense focus on the 'filter problem' that persisted from the mid-1950s to the mid-1960s, featuring collaborations between cigarette producers and large American chemical and textile companies to develop effective filters. In addition, the documents reveal how cigarette filter researchers' growing scientific knowledge of smoke chemistry led to increasing recognition that filters were unlikely to offer significant health protection. One of the primary concerns of cigarette producers was to design cigarette filters that could be economically incorporated into the massive scale of cigarette production. The synthetic plastic cellulose acetate

  20. [{sup 18}F]F15599, a novel 5-HT{sub 1A} receptor agonist, as a radioligand for PET neuroimaging

    Energy Technology Data Exchange (ETDEWEB)

    Lemoine, Laetitia; Verdurand, Mathieu [Universite de Lyon, Laboratory of Neuropharmacology, Lyon (France); CERMEP - Imagerie du Vivant, PET Department, Lyon (France); Vacher, Bernard; Blanc, Elodie; Newman-Tancredi, Adrian [Centre de Recherches Pierre Fabre, Castres (France); Le Bars, Didier [CERMEP - Imagerie du Vivant, PET Department, Lyon (France); Zimmer, Luc [Universite de Lyon, Laboratory of Neuropharmacology, Lyon (France); CERMEP - Imagerie du Vivant, PET Department, Lyon (France); CERMEP - Imagerie du Vivant, ANIMAGE Department, Lyon (France)

    2010-03-15

    The serotonin-1A (5-HT{sub 1A}) receptor is implicated in the pathophysiology of major neuropsychiatric disorders. Thus, the functional imaging of 5-HT{sub 1A} receptors by positron emission tomography (PET) may contribute to the understanding of its role in those pathologies and their therapeutics. These receptors exist in high- and low-affinity states and it is proposed that agonists bind preferentially to the high-affinity state of the receptor and therefore could provide a measure of the functional 5-HT{sub 1A} receptors. Since all clinical PET 5-HT{sub 1A} radiopharmaceuticals are antagonists, it is of great interest to develop a{sup 18}F labelled agonist. F15599 (3-chloro-4-fluorophenyl-(4-fluoro-4{l_brace}[(5-methyl-pyrimidin-2-ylmethyl)-amino]-methyl{r_brace}-piperidin-1-yl)-methanone) is a novel ligand with high affinity and selectivity for 5-HT{sub 1A} receptors and is currently tested as an antidepressant. In pharmacological tests in rat, it exhibits preferential agonist activity at post-synaptic 5-HT{sub 1A} receptors in cortical brain regions. Here, its nitro-precursor was synthesised and radiolabelled via a fluoronucleophilic substitution. Radiopharmacological evaluations included in vitro and ex vivo autoradiography in rat brain and PET scans on rats and cats. Results were compared with simultaneous studies using [{sup 18}F]MPPF, a validated 5-HT{sub 1A} antagonist radiopharmaceutical. The chemical and radiochemical purities of [{sup 18}F]F15599 were >98%. In vitro [{sup 18}F ]F15599 binding was consistent with the known 5-HT{sub 1A} receptors distribution (hippocampus, dorsal raphe nucleus, and notably cortical areas) and addition of Gpp(NH)p inhibited [{sup 18}F ]F15599 binding, consistent with a specific binding to G protein-coupled receptors. In vitro binding of [{sup 18}F]F15599 was blocked by WAY100635 and 8-OH-DPAT, respectively, prototypical 5-HT{sub 1A} antagonist and agonist. The ex vivo and in vivo studies demonstrated that the radiotracer

  1. Radiation Characterization Summary: ACRR Central Cavity Free-Field Environment with the 32-Inch Pedestal at the Core Centerline (ACRR-FF-CC-32-cl).

    Energy Technology Data Exchange (ETDEWEB)

    Vega, Richard Manuel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Parma, Edward J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Naranjo, Gerald E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lippert, Lance L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Vehar, David W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Griffin, Patrick J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-08-01

    This document presents the facilit y - recommended characteri zation o f the neutron, prompt gamma - ray, and delayed gamma - ray radiation fields in the Annular Core Research Reactor ( ACRR ) for the cen tral cavity free - field environment with the 32 - inch pedestal at the core centerline. The designation for this environmen t is ACRR - FF - CC - 32 - cl. The neutron, prompt gamma - ray , and delayed gamma - ray energy spectra , uncertainties, and covariance matrices are presented as well as radial and axial neutron and gamma - ray fluence profiles within the experiment area of the cavity . Recommended constants are given to facilitate the conversion of various dosimetry readings into radiation metrics desired by experimenters. Representative pulse operations are presented with conversion examples . Acknowledgements The authors wish to th ank the Annular Core Research Reactor staff and the Radiation Metrology Laboratory staff for their support of this work . Also thanks to David Ames for his assistance in running MCNP on the Sandia parallel machines.

  2. Removal of malathion from aqueous solution using De-Acidite FF-IP resin and determination by UPLC-MS/MS: equilibrium, kinetics and thermodynamics studies.

    Science.gov (United States)

    Naushad, Mu; Alothman, Z A; Khan, M R

    2013-10-15

    In the present study, De-Acidite FF-IP resin was used to remove a highly toxic and persistent organophosphorus pesticide (malathion) from the aqueous solution. Batch experiments were performed as a function of various experimental parameters such as effect of pH (2-10), contact time (10-120 min), resin dose (0.05-0.5 g), initial malathion concentration (0.5-2.5 µg mL(-1)) and temperature (25-65°C). The concentration of malathion was determined using a sensitive, selective and rapid ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. The uptake rate of malathion on De-Acidite FF-IP resin was rapid and equilibrium established within 40 min. Kinetics studies showed better applicability for pseudo-second-order model. The equilibrium data was fitted to Langmuir and Freundlich isotherm models and the isotherm constants were calculated for malathion. The values of thermodynamic parameters (ΔG(0), ΔH(0) and ΔS(0)) were computed from the Van't Hoff plot of lnKC vs. 1/T which showed that the adsorption of malathion was feasible, endothermic and spontaneous. The regeneration studies were carried out which demonstrated a decrease in the recovery of malathion from 95% to 68% after five consecutive cycles. Breakthrough and exhaustive capacities of malathion were found to be 1.25 mg g(-1) and 3.5 mg g(-1), respectively. © 2013 Elsevier B.V. All rights reserved.

  3. Flattening filter free beams from TrueBeam and Versa HD units: Evaluation of the parameters for quality assurance

    Energy Technology Data Exchange (ETDEWEB)

    Fogliata, Antonella, E-mail: antonella.fogliata@humanitas.it; Reggiori, Giacomo; Stravato, Antonella; Scorsetti, Marta; Cozzi, Luca [Radiotherapy and Radiosurgery Department, Humanitas Research Hospital, Milan-Rozzano I-20098 (Italy); Fleckenstein, Jens; Schneider, Frank; Lohr, Frank [Department of Radiation Oncology, University Medical Center Mannheim, University of Heidelberg, Mannheim D-68167 (Germany); Pachoud, Marc; Ghandour, Sarah [Radiation Oncology Department, Hôpital Riviera Chablais, Vevey CH-1800 (Switzerland); Krauss, Harald [Radio-Oncology Department, Kaiser Franz Josef Spital, Vienna A-1100 (Austria)

    2016-01-15

    Purpose: Flattening filter free (FFF) beams generated by medical linear accelerators are today clinically used for stereotactical and non-stereotactical radiotherapy treatments. Such beams differ from the standard flattened beams (FF) in the high dose rate and the profile shape peaked on the beam central axis. Definition of new parameters as unflatness and slope for FFF beams has been proposed based on a renormalization factor for FFF profiles. The present study aims to assess the dosimetric differences between FFF beams generated by linear accelerators from different vendors, and to provide renormalization and parameter data of the two kinds of units. Methods: Dosimetric data from two Varian TrueBeam and two Elekta Versa HD linear accelerators, all with 6 and 10 MV nominal accelerating potentials, FF and FFF modes have been collected. Renormalization factors and related fit parameters according to Fogliata et al. [“Definition of parameters for quality assurance of flattening filter free (FFF) photon beams in radiation therapy,” Med. Phys. 39, 6455–6464 (2012)] have been evaluated for FFF beams of both units and energies. Unflatness and slope parameters from profile curves were evaluated. Dosimetric differences in terms of beam penetration and near-the-surface dose were also assessed. Results: FFF profile parameters have been updated; renormalization factors and unflatness from the Varian units are consistent with the published data. Elekta FFF beam qualities, different from the Varian generated beams, tend to express similar behaviour as the FF beam of the corresponding nominal energy. TPR{sub 20,10} for 6 and 10 MV FF and FFF TrueBeam beams are 0.665, 0.629 (6 MV) and 0.738, 0.703 (10 MV). The same figures for Versa HD units are 0.684, 0.678 (6 MV) and 0.734, 0.721 (10 MV). Conclusions: Renormalization factor and unflatness parameters evaluated from Varian and Elekta FFF beams are provided, in particular renormalization factors table and fit parameters.

  4. SU-E-T-435: Flattening Filter Free Beams for Head and Neck IMRT and VMAT Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Ghahremani, S; Chavez, R; Li, Y; Crownover, R; Baacke, D; Papanikolaou, N; Stathakis, S [University of Texas HSC SA, San Antonio, TX (United States)

    2015-06-15

    Purpose: To investigate if there is benefits of using flattening filter free (FFF) versus flattening filter (FF) beams during plan optimization for head and neck targets. Methods: Five head and neck cancer patients previously treated were selected for this study. Each plan was optimized for volumetric modulated arc therapy (VMAT) using 2 full arcs. Target volumes and the organs at risk (OAR) were outlined by the same physician. The prescription doses for each patient and the dose limits for each OAR were specified by the physician. For each patient four plans were created by varying the photon beam energy (6MV vs 10MV) and the use of FF or FFF. For each patient the prescription dose and OAR dose limits remained unchanged. Furthermore, the number of optimization iterations remained the same for each plan without user interference. The plans were compared using dose volume histograms, conformity and homogeneity indices. Results: Our results showed that the plans optimized with FF beams produced more homogeneous dose distributions in the PTV than the ones with FFF beams (0.92 vs. 0.86 and 0.92 vs.85 for 6MVFF, 6MVFFF, 10MVFF and 10MVFFF respectively). The conformity was better for FFF beams than for FF beams (1.26 vs. 1.20 and 1.27 vs. 1.21 for 6MVFF, 6MVFFF, 10MVFF and 10MVFFF respectively). The overall minimum, maximum and means doses were reduced for the FFF plans by approximately 4% to 6%. All FFF plans allowed more sparing of organs at risk by 7% to 9% on average. Only one 10MVFFF plan had a 1% higher dose than the respective 10MVFF for the spinal cord. Conclusion: The 6MVFFF and 10MVFFF beams illustrated the improvement of normal tissue sparing while achieving similar target dose distribution compared to 6MVFF and 10MVFF beams. Further investigation is required to determine the magnitude of improvement. case specific, fluence-based optimization improved both PTV and OAR dosimetry in 80% of cases.

  5. 40 CFR 63.8540 - What parts of my plant does this subpart cover?

    Science.gov (United States)

    2010-07-01

    ... is a new affected source if construction of the affected source began after July 22, 2002, and you met the applicability criteria at the time you began construction. (f) An affected source is... retrofitting with a dry lime injection fabric filter (DIFF), dry lime scrubber/fabric filter (DLS/FF), or wet...

  6. From Microwave Filter to Digital Filter and Back Again

    DEFF Research Database (Denmark)

    Dalby, Arne Brejning

    1989-01-01

    A new very simple state variable flow graph representation for interdigital transmission line bandpass filters is presented, which has led to two important results: 1) A new type of digital filter with properties, that surpass the properties of most other (all pole) digital filtertypes. 2) The st...

  7. AER image filtering

    Science.gov (United States)

    Gómez-Rodríguez, F.; Linares-Barranco, A.; Paz, R.; Miró-Amarante, L.; Jiménez, G.; Civit, A.

    2007-05-01

    Address Event Representation (AER) is an emergent neuromorphic interchip communication protocol that allows real-time virtual massive connectivity among huge number of neurons located on different chips.[1] By exploiting high speed digital communication circuits (with nano-seconds timing), synaptic neural connections can be time multiplexed, while neural activity signals (with mili-seconds timings) are sampled at low frequencies. Neurons generate "events" according to their activity levels. That is, more active neurons generate more events per unit time and access the interchip communication channel more frequently than neurons with low activity. In Neuromorphic system development, AER brings some advantages to develop real-time image processing system: (1) AER represents the information like time continuous stream not like a frame; (2) AER sends the most important information first (although this depends on the sender); (3) AER allows to process information as soon as it is received. When AER is used in artificial vision field, each pixel is considered like a neuron, so pixel's intensity is represented like a sequence of events; modifying the number and the frequency of these events, it is possible to make some image filtering. In this paper we present four image filters using AER: (a) Noise addition and suppression, (b) brightness modification, (c) single moving object tracking and (d) geometrical transformations (rotation, translation, reduction and magnification). For testing and debugging, we use USB-AER board developed by Robotic and Technology of Computers Applied to Rehabilitation (RTCAR) research group. This board is based on an FPGA, devoted to manage the AER functionality. This board also includes a micro-controlled for USB communication, 2 Mbytes RAM and 2 AER ports (one for input and one for output).

  8. Particle Kalman Filtering: A Nonlinear Framework for Ensemble Kalman Filters

    KAUST Repository

    Hoteit, Ibrahim

    2010-09-19

    Optimal nonlinear filtering consists of sequentially determining the conditional probability distribution functions (pdf) of the system state, given the information of the dynamical and measurement processes and the previous measurements. Once the pdfs are obtained, one can determine different estimates, for instance, the minimum variance estimate, or the maximum a posteriori estimate, of the system state. It can be shown that, many filters, including the Kalman filter (KF) and the particle filter (PF), can be derived based on this sequential Bayesian estimation framework. In this contribution, we present a Gaussian mixture‐based framework, called the particle Kalman filter (PKF), and discuss how the different EnKF methods can be derived as simplified variants of the PKF. We also discuss approaches to reducing the computational burden of the PKF in order to make it suitable for complex geosciences applications. We use the strongly nonlinear Lorenz‐96 model to illustrate the performance of the PKF.

  9. Front Surface Tandem Filters using Sapphire (Al2O3) Substrates for Spectral Control in thermophotovoltaic Energy Conversion Systems

    International Nuclear Information System (INIS)

    T Rahmlow, Jr.; J Lazo-Wasem; E Gratrix; P Fourspring; D DePoy

    2005-01-01

    Front surface filters provide an effective means of improving thermophotovoltaic (TPV) system efficiency through spectral control of incident radiant energy. A front surface filter reflects the below band gap photons that can not be converted by the TPV cell back towards the high temperature radiator and allows convertible above band gap photons to pass through the filter into the TPV cell for conversion to electricity. The best spectral control efficiency to date has been demonstrated by front surface, tandem filters that combine an interference filter and an InPAs layer (plasma filter) in series. The InPAs material is a highly doped, epitaxially grown layer on an InP substrate. These tandem filter designs have been fabricated with energy and angle weighted spectral efficiencies of 76% for TPV cells with a 2.08(micro)m (0.6eV) band gap [1]. An alternative to the InPAs layer on an InP substrate is an Al 2 O 3 (sapphire) substrate. The use of Al 2 O 3 may increase transmission of above band gap photons, increase the mechanical strength of the tandem filter, and lower the cost of the tandem filter, all at the expense of lower spectral efficiency. This study presents design and fabrication results for front surface tandem filters that use an Al 2 O 3 substrate for 2.08(micro)m band gap TPV cells

  10. Application of DFT Filter Banks and Cosine Modulated Filter Banks in Filtering

    Science.gov (United States)

    Lin, Yuan-Pei; Vaidyanathan, P. P.

    1994-01-01

    None given. This is a proposal for a paper to be presented at APCCAS '94 in Taipei, Taiwan. (From outline): This work is organized as follows: Sec. II is devoted to the construction of the new 2m channel under-decimated DFT filter bank. Implementation and complexity of this DFT filter bank are discussed therein. IN a similar manner, the new 2m channel cosine modulated filter bank is discussed in Sec. III. Design examples are given in Sec. IV.

  11. Filters in Fuzzy Class Theory

    Czech Academy of Sciences Publication Activity Database

    Kroupa, Tomáš

    2008-01-01

    Roč. 159, č. 14 (2008), s. 1773-1787 ISSN 0165-0114 R&D Projects: GA MŠk 1M0572; GA AV ČR KJB100300502 Institutional research plan: CEZ:AV0Z10750506 Keywords : filter * prime filter * fuzzy class theory Subject RIV: BA - General Mathematics Impact factor: 1.833, year: 2008

  12. Derivative free filtering using Kalmtool

    DEFF Research Database (Denmark)

    Bayramoglu, Enis; Hansen, Søren; Ravn, Ole

    2010-01-01

    In this paper we present a toolbox enabling easy evaluation and comparison of different filtering algorithms. The toolbox is called Kalmtool 4 and is a set of MATLAB tools for state estimation of nonlinear systems. The toolbox contains functions for extended Kalman filtering as well as for DD1 fi...

  13. Chopped filter for nuclear spectroscopy

    International Nuclear Information System (INIS)

    Koyama, J.

    1980-12-01

    Some of the theoretical and practical factors affecting the energy resolution of a spectrometry system are considered, specially those related to t he signal-to-noise ratio, and a time-variant filter with the transfer function of the theoretical optimum filter, during its active time, is proposed. A prototype has been tested and experimental results are presented. (Author) [pt

  14. Cluster Based Vector Attribute Filtering

    NARCIS (Netherlands)

    Kiwanuka, Fred N.; Wilkinson, Michael H.F.

    2016-01-01

    Morphological attribute filters operate on images based on properties or attributes of connected components. Until recently, attribute filtering was based on a single global threshold on a scalar property to remove or retain objects. A single threshold struggles in case no single property or

  15. Some arithmetically symmetrical bandpass filters

    Science.gov (United States)

    Paranasi, P.; Roy, S. C. D.

    1981-01-01

    A combination of the conventional and Matthaei lowpass-bandpass transformations is shown to result in some bandpass filters having very good arithmetic symmetry. The technique presented is applicable to the Butterworth and inverse Chebyshev types of magnitude approximations and the Bessel type of delay approximations. It is not valid, however, for the Chebyshev and elliptic varieties of filters.

  16. Properties of auxiliary filtering materials

    Energy Technology Data Exchange (ETDEWEB)

    Rudenko, L.I.; Sklyar, V.T.

    1981-01-01

    The authors have studied the physicochemical and filtering properties of the perlites FP-1 and FP-2, kieselguhr, diatomite, asbestos, wood pulp, and the diatomite powders Spidplace and Saperaid. They propose a classification for filtering materials according to their properties when mechanical impurities are being removed from the additives.

  17. High flow ceramic pot filters

    NARCIS (Netherlands)

    van Halem, D.; van der Laan, H.; Soppe, A. I.A.; Heijman, S.G.J.

    2017-01-01

    Ceramic pot filters are considered safe, robust and appropriate technologies, but there is a general consensus that water revenues are limited due to clogging of the ceramic element. The objective of this study was to investigate the potential of high flow ceramic pot filters to produce more

  18. Mixtures of skewed Kalman filters

    KAUST Repository

    Kim, Hyoungmoon; Ryu, Duchwan; Mallick, Bani K.; Genton, Marc G.

    2014-01-01

    Normal state-space models are prevalent, but to increase the applicability of the Kalman filter, we propose mixtures of skewed, and extended skewed, Kalman filters. To do so, the closed skew-normal distribution is extended to a scale mixture class

  19. Mobile filters in nuclear engineering

    International Nuclear Information System (INIS)

    Meuter, R.

    1979-01-01

    The need for filters with high efficiencies which may be used at any place originated in nuclear power plants. Filters of this type, called Filtermobil, have been developed by Sulzer. They have been used successfully in nuclear plants for several years. (orig.) [de

  20. Implicit LES using adaptive filtering

    Science.gov (United States)

    Sun, Guangrui; Domaradzki, Julian A.

    2018-04-01

    In implicit large eddy simulations (ILES) numerical dissipation prevents buildup of small scale energy in a manner similar to the explicit subgrid scale (SGS) models. If spectral methods are used the numerical dissipation is negligible but it can be introduced by applying a low-pass filter in the physical space, resulting in an effective ILES. In the present work we provide a comprehensive analysis of the numerical dissipation produced by different filtering operations in a turbulent channel flow simulated using a non-dissipative, pseudo-spectral Navier-Stokes solver. The amount of numerical dissipation imparted by filtering can be easily adjusted by changing how often a filter is applied. We show that when the additional numerical dissipation is close to the subgrid-scale (SGS) dissipation of an explicit LES the overall accuracy of ILES is also comparable, indicating that periodic filtering can replace explicit SGS models. A new method is proposed, which does not require any prior knowledge of a flow, to determine the filtering period adaptively. Once an optimal filtering period is found, the accuracy of ILES is significantly improved at low implementation complexity and computational cost. The method is general, performing well for different Reynolds numbers, grid resolutions, and filter shapes.

  1. Tunable Multiband Microwave Photonic Filters

    Directory of Open Access Journals (Sweden)

    Mable P. Fok

    2017-11-01

    Full Text Available The increasing demand for multifunctional devices, the use of cognitive wireless technology to solve the frequency resource shortage problem, as well as the capabilities and operational flexibility necessary to meet ever-changing environment result in an urgent need of multiband wireless communications. Spectral filter is an essential part of any communication systems, and in the case of multiband wireless communications, tunable multiband RF filters are required for channel selection, noise/interference removal, and RF signal processing. Unfortunately, it is difficult for RF electronics to achieve both tunable and multiband spectral filtering. Recent advancements of microwave photonics have proven itself to be a promising candidate to solve various challenges in RF electronics including spectral filtering, however, the development of multiband microwave photonic filtering still faces lots of difficulties, due to the limited scalability and tunability of existing microwave photonic schemes. In this review paper, we first discuss the challenges that were facing by multiband microwave photonic filter, then we review recent techniques that have been developed to tackle the challenge and lead to promising developments of tunable microwave photonic multiband filters. The successful design and implementation of tunable microwave photonic multiband filter facilitate the vision of dynamic multiband wireless communications and radio frequency signal processing for commercial, defense, and civilian applications.

  2. Durable superhydrophobic and superoleophilic filter paper for oil–water separation prepared by a colloidal deposition method

    International Nuclear Information System (INIS)

    Du, Chuan; Wang, Jiadao; Chen, Zhifu; Chen, Darong

    2014-01-01

    Graphical abstract: - Highlights: • A method for fabricating durable superhydrophobic filter paper was developed. • Oil–water separation efficiency exceeds 99% using the as-prepared filter paper. • The as-prepared filter paper has good recyclability and durability. • The method is easy, low cost and can be industrialized. - Abstract: A method for manufacturing durable superhydrophobic and superoleophilic filter paper for oil–water separation was developed via colloidal deposition. A porous film composed of PTFE nanoparticles was formed on filter paper, which was superhydrophobic with a water contact angle of 155.5° and superoleophilic with an oil contact angle of 0°. The obtained filter paper could separate a series of oil–water mixtures effectively with high separation efficiencies over 99%. Besides, the as-prepared filter paper kept stable superhydrophobicity and high separation efficiency even after 30 cycle times and could also work well under harsh environmental conditions like strong acidic or alkaline solutions, high temperature and ultraviolet irradiation. Compared with other approaches for fabricating oil–water materials, this approach is able to fabricate full-scale durable and practical oil–water materials easily and economically. The as-prepared filter paper is a promising candidate for oil–water separation

  3. Hydrodynamics of microbial filter feeding

    DEFF Research Database (Denmark)

    Nielsen, Lasse Tor; Asadzadeh, Seyed Saeed; Dölger, Julia

    2017-01-01

    Microbial filter feeders are an important group of grazers, significant to the microbial loop, aquatic food webs, and biogeochemical cycling. Our understanding of microbial filter feeding is poor, and, importantly, it is unknown what force microbial filter feeders must generate to process adequate......-feeding choanoflagellate Diaphanoeca grandis using particle tracking, and demonstrate that the current understanding of microbial filter feeding is inconsistent with computational fluid dynamics (CFD) and analytical estimates. Both approaches underestimate observed filtration rates by more than an order of magnitude......; the beating flagellum is simply unable to draw enough water through the fine filter. We find similar discrepancies for other choanoflagellate species, highlighting an apparent paradox. Our observations motivate us to suggest a radically different filtration mechanism that requires a flagellar vane (sheet...

  4. Apparatus for filtering radioactive fluids

    International Nuclear Information System (INIS)

    Gischel, E.H.

    1975-01-01

    Apparatus is provided for filtering radioactive particles from the cooling and/or auxiliary process water of a nuclear reactor, or nuclear fuel processing plant, or other installations wherein radioactive fluid systems are known to exist. The apparatus affords disposal of the captured particles in a manner which minimizes the exposure of operating personnel to radioactivity. The apparatus comprises a housing adapted to contain a removable filter cartridge assembly, a valve normally closing the lower end of the housing, an upwardly-open shipping cask located below the valve, and an elongated operating rod assembly projecting upwardly from the filter cartridge assembly and through the upper end of the housing to enable a workman to dismount the filter cartridge assembly from its housing and to lower the filter cartridge assembly through the valve and into the cask from a remote location above the housing. (U.S.)

  5. Vectorization of linear discrete filtering algorithms

    Science.gov (United States)

    Schiess, J. R.

    1977-01-01

    Linear filters, including the conventional Kalman filter and versions of square root filters devised by Potter and Carlson, are studied for potential application on streaming computers. The square root filters are known to maintain a positive definite covariance matrix in cases in which the Kalman filter diverges due to ill-conditioning of the matrix. Vectorization of the filters is discussed, and comparisons are made of the number of operations and storage locations required by each filter. The Carlson filter is shown to be the most efficient of the filters on the Control Data STAR-100 computer.

  6. Tracking speckle displacement by double Kalman filtering

    Institute of Scientific and Technical Information of China (English)

    Donghui Li; Li Guo

    2006-01-01

    @@ A tracking technique using two sequentially-connected Kalman filter for tracking laser speckle displacement is presented. One Kalman filter tracks temporal speckle displacement, while another Kalman filter tracks spatial speckle displacement. The temporal Kalman filter provides a prior for the spatial Kalman filter, and the spatial Kalman filter provides measurements for the temporal Kalman filter. The contribution of a prior to estimations of the spatial Kalman filter is analyzed. An optical analysis system was set up to verify the double-Kalman-filter tracker's ability of tracking laser speckle's constant displacement.

  7. Understanding core conductor fabrics

    International Nuclear Information System (INIS)

    Swenson, D E

    2011-01-01

    ESD Association standard test method ANSI/ESD STM2.1 - Garments (STM2.1), provides electrical resistance test procedures that are applicable for materials and garments that have surface conductive or surface dissipative properties. As has been reported in other papers over the past several years 1 fabrics are now used in many industries for electrostatic control purposes that do not have surface conductive properties and therefore cannot be evaluated using the procedures in STM2.1 2 . A study was conducted to compare surface conductive fabrics with samples of core conductor fibre based fabrics in order to determine differences and similarities with regards to various electrostatic properties. This work will be used to establish a new work item proposal within WG-2, Garments, in the ESD Association Standards Committee in the USA.

  8. LHCb: Fabric Management with Diskless Servers and Quattor on LHCb

    CERN Multimedia

    Schweitzer, P; Brarda, L; Neufeld, N

    2011-01-01

    Large scientific experiments nowadays very often are using large computer farms to process the events acquired from the detectors. In LHCb a small sysadmin team manages 1400 servers of the LHCb Event Filter Farm, but also a wide variety of control servers for the detector electronics and infrastructure computers: file servers, gateways, DNS, DHCP and others. This variety of servers could not be handled without a solid fabric management system. We choose the Quattor toolkit for this task. We will present our use of this toolkit, with an emphasis on how we handle our diskless nodes (Event filter farm nodes and computers embedded in the acquisition electronic cards). We will show our current tests to replace the standard (RedHat/Scientific Linux) way of handling diskless nodes to fusion filesystems and how it improves fabric management.

  9. Development of the code for filter calculation

    International Nuclear Information System (INIS)

    Gritzay, O.O.; Vakulenko, M.M.

    2012-01-01

    This paper describes a calculation method, which commonly used in the Neutron Physics Department to develop a new neutron filter or to improve the existing neutron filter. This calculation is the first step of the traditional filter development procedure. It allows easy selection of the qualitative and quantitative contents of a composite filter in order to receive the filtered neutron beam with given parameters

  10. A Novel CPW BandPass Filter Integrating Periodic Rectangular Slot Cells

    Directory of Open Access Journals (Sweden)

    Fouad Aytouna

    2015-12-01

    Full Text Available In this paper, we introduce the design and the achievement of a Bandpass filter structure based on the use of rectangular slot cell. The originality of this work is to achieve a coplanar filter easy to integrate with microwave planar circuits and having a wide frequency bandwidth. The proposed bandpass filter is a low cost and compact planar filter structure. The final circuit is simulated by using two electromagnetic solvers, ADS and HFSS. The validation into simulation is based on using optimization methods integrated into the both solvers. Simulations have taken into account a high meshing density to cover the whole circuit. The fabricated bandpass filter has an area of 35X31mm2 and having a good insertion loss around -0.75dB in the bandwidth. The comparison between simulation and measurement results presents a good agreement.

  11. A planar and tunable bandpass filter on a ferrite substrate with integrated windings

    KAUST Repository

    Arabi, Eyad A.

    2015-05-01

    Tunable Filters that are based on ferrite materials are often biased by external magnets or coils which are large and bulky. In this work a completely planar, CPW-based bandpass filter is presented with integrated windings. Due to these windings the size of the filter is only 26mm × 34mm × 0.38mm which is orders of magnitude smaller than the traditional designs with external windings. The filter is realized by electroplating of Copper over seed layers of Titanium and Gold over a YIG substrate. The fabricated filter achieves a tunability of 3.4% without any external magnets or coils. A good insertion loss of 2.3 dBs and rejection greater than 50 dBs have been obtained. To the best of the authors knowledge, this design is the first ferrite-based design that is completely planar and self-biased.

  12. UWB Bandpass Filter with Ultra-wide Stopband based on Ring Resonator

    Science.gov (United States)

    Kazemi, Maryam; Lotfi, Saeedeh; Siahkamari, Hesam; Mohammadpanah, Mahmood

    2018-04-01

    An ultra-wideband (UWB) bandpass filter with ultra-wide stopband based on a rectangular ring resonator is presented. The filter is designed for the operational frequency band from 4.10 GHz to 10.80 GHz with an ultra-wide stopband from 11.23 GHz to 40 GHz. The even and odd equivalent circuits are used to achieve a suitable analysis of the proposed filter performance. To verify the design and analysis, the proposed bandpass filter is simulated using full-wave EM simulator Advanced Design System and fabricated on a 20mil thick Rogers_RO4003 substrate with relative permittivity of 3.38 and a loss tangent of 0.0021. The proposed filter behavior is investigated and simulation results are in good agreement with measurement results.

  13. Fabrication of multilayer nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Jasveer, E-mail: kaurjasveer89@gmail.com; Singh, Avtar; Kumar, Davinder [Department of Physics, Punjabi University Patiala, 147002, Punjab (India); Thakur, Anup; Kaur, Raminder, E-mail: raminder-k-saini@yahoo.com [Department of Basic and Applied Sciences, Punjabi University Patiala, 147002, Punjab (India)

    2016-05-06

    Multilayer nanowires were fabricated by potentiostate ectrodeposition template synthesis method into the pores of polycarbonate membrane. In present work layer by layer deposition of two different metals Ni and Cu in polycarbonate membrane having pore size of 600 nm were carried out. It is found that the growth of nanowires is not constant, it varies with deposition time. Scanning electron microscopy (SEM) is used to study the morphology of fabricated multilayer nanowires. An energy dispersive X-ray spectroscopy (EDS) results confirm the composition of multilayer nanowires. The result shows that multilayer nanowires formed is dense.

  14. MOX Fabrication Isolation Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Eric L. Shaber; Bradley J Schrader

    2005-08-01

    This document provides a technical position on the preferred level of isolation to fabricate demonstration quantities of mixed oxide transmutation fuels. The Advanced Fuel Cycle Initiative should design and construct automated glovebox fabrication lines for this purpose. This level of isolation adequately protects the health and safety of workers and the general public for all mixed oxide (and other transmutation fuel) manufacturing efforts while retaining flexibility, allowing parallel development and setup, and minimizing capital expense. The basis regulations, issues, and advantages/disadvantages of five potential forms of isolation are summarized here as justification for selection of the preferred technical position.

  15. Fabrication of multilayer nanowires

    International Nuclear Information System (INIS)

    Kaur, Jasveer; Singh, Avtar; Kumar, Davinder; Thakur, Anup; Kaur, Raminder

    2016-01-01

    Multilayer nanowires were fabricated by potentiostate ectrodeposition template synthesis method into the pores of polycarbonate membrane. In present work layer by layer deposition of two different metals Ni and Cu in polycarbonate membrane having pore size of 600 nm were carried out. It is found that the growth of nanowires is not constant, it varies with deposition time. Scanning electron microscopy (SEM) is used to study the morphology of fabricated multilayer nanowires. An energy dispersive X-ray spectroscopy (EDS) results confirm the composition of multilayer nanowires. The result shows that multilayer nanowires formed is dense.

  16. On-line filtering

    International Nuclear Information System (INIS)

    Verkerk, C.

    1978-01-01

    Present day electronic detectors used in high energy physics make it possible to obtain high event rates and it is likely that future experiments will face even higher data rates than at present. The complexity of the apparatus increases very rapidly with time and also the criteria for selecting desired events become more and more complex. So complex in fact that the fast trigger system cannot be designed to fully cope with it. The interesting events become thus contaminated with multitudes of uninteresting ones. To distinguish the 'good' events from the often overwhelming background of other events one has to resort to computing techniques. Normally this selection is made in the first part of the analysis of the events, analysis normally performed on a powerful scientific computer. This implies however that many uninteresting or background events have to be recorded during the experiment for subsequent analysis. A number of undesired consequences result; and these constitute a sufficient reason for trying to perform the selection at an earlier stage, in fact ideally before the events are recorded on magnetic tape. This early selection is called 'on-line filtering' and it is the topic of the present lectures. (Auth.)

  17. Design and fabrication of advanced EUV diffractive elements

    Energy Technology Data Exchange (ETDEWEB)

    Naulleau, Patrick P.; Liddle, J. Alexander; Salmassi, Farhad; Anderson, Erik H.; Gullikson, Eric M.

    2003-11-16

    As extreme ultraviolet (EUV) lithography approaches commercial reality, the development of EUV-compatible diffractive structures becomes increasingly important. Such devices are relevant to many aspects of EUV technology including interferometry, illumination, and spectral filtering. Moreover, the current scarcity of high power EUV sources makes the optical efficiency of these diffractive structures a paramount concern. This fact has led to a strong interest in phase-enhanced diffractive structures. Here we describe recent advancements made in the fabrication of such devices.

  18. Airborne effluent control at fuel enrichment, conversion, and fabrication plants

    International Nuclear Information System (INIS)

    Mitchell, M.E.

    1976-01-01

    Uranium conversion, enrichment, and fuel fabrication facilities generate gaseous wastes that must be treated prior to being discharged to the atmosphere. Since all three process and/or handle similar compounds, they also encounter similar gaseous waste disposal problems, the majority of which are treated in a similar manner. Ventilation exhausts from personnel areas and equipment off-gases that do not contain corrosive gases (such as HF) are usually passed through roughening and/or HEPA filters prior to release. Ventilation exhausts that contain larger quantities of particles, such as the conversion facilities' U 3 O 8 sampling operation, are passed through bag filters or cyclone separators, while process off-gases containing corrosive materials are normally treated by sintered metal filters or scrubbers. The effectiveness of particle removal varies from about 90 percent for a scrubber alone to more than 99.9 percent for HEPA filters or a combination of the various filters and scrubbers. The removal of nitrogen compounds (N 2 , HNO 3 , NO/sub x/, and NH 3 ) is accomplished by scrubbers in the enrichment and fuel fabrication facilities. The conversion facility utilizes a nitric acid recovery facility for both pollution control and economic recovery of raw materials. Hydrogen removal from gaseous waste streams is generally achieved with burners. Three different systems are currently utilized by the conversion, enrichment, and fuel fabrication plants to remove gaseous fluorides from airborne effluents. The HF-rich streams, such as those emanating from the hydrofluorination and fluorine production operations of the conversion plant, are passed through condensers to recover aqueous hydrofluoric acid

  19. Feasibility of Colliding-beam fast-fission reactor via 238U80++238 U80+ --> 4 FF + 5n + 430 MeV beam with suppressed plutonium and direct conversion of fission fragment (FF) energy into electricity and/or Rocket propellant with high specific impulse

    Science.gov (United States)

    Maglich, Bogdan; Hester, Tim; Calsec Collaboration

    2015-10-01

    Uranium-uranium colliding beam experiment1, used fully ionized 238U92+ at energy 100GeV --> accelerated through 3 MV accelerator, will collide beam 240 MeV --> 4 FF + 5n + 430 MeV. Using a simple model1 fission σf ~ 100 b. Suppression of Pu by a factor of 106 will be achieved because NO thermal neutron fission can take place; only fast, 1-3 MeV, where σabs is negligible. Direct conversion of 95% of 430 MeV produced is carried by electrically charged FFs which are magnetically funneled for direct conversion of energy of FFs via electrostatic decelerators4,11. 90% of 930 MeV is electrically recoverable. Depending on the assumptions, we project electric _ power density production of 20 to 200 MWe m-3, equivalent to Thermal 1.3 - 13 GWthm-3. If one-half of unburned U is used for propulsion while rest powers system, heavy FF ion mass provides specific impulse Isp = 106 sec., 103 times higher than current rocket engines.

  20. Effect of nanoclay on durability and mechanical properties of flax fabric reinforced geopolymer composites

    Directory of Open Access Journals (Sweden)

    H. Assaedi

    2017-03-01

    Full Text Available The main concern of using natural fibres as reinforcement in geopolymer composites is the durability of the fibres. Geopolymers are alkaline in nature because of the alkaline solution that is required for activating the geopolymer reaction. The alkalinity of the matrix, however, is the key reason of the degradation of natural fibres. The purpose of this study is to determine the effect of nanoclay (NC loading on the mechanical properties and durability of flax fabric (FF reinforced geopolymer composites. The durability of composites after 4 and 32 weeks at ambient temperature is presented. The microstructure of geopolymer matrices was investigated using X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FTIR and scanning electron microscopy (SEM. The results showed that the incorporation of NC has a positive impact on the physical properties, mechanical performance, and durability of FF reinforced geopolymer composites. The presence of NC has a positive impact through accelerating the geopolymerization, reducing the alkalinity of the system and increasing the geopolymer gel.

  1. Regenerative-filter-incinerator device

    Energy Technology Data Exchange (ETDEWEB)

    Rosebrock, T.L.

    1977-10-18

    A regenerative-filter-incinerator device, for use in the exhaust system of a diesel engine, includes a drum-like regenerative-heat exchanger-filter assembly rotatably mounted within a housing that is adapted to be installed directly in the exhaust gas stream discharged from a diesel engine as close to the engine as possible. The regenerative-heat exchanger-filter assembly provides an inner chamber which serves as a reaction chamber for the secondary combustion of exhaust gases including particulates discharged from the engine. The regenerative-heat exchanger-filter assembly includes separately rotatable heat exchange-filter elements pervious to radial flow of fluid therethrough and adapted to filter out particulates from the exhaust gases and to carry them into the reaction chamber. During engine operation, the reaction chamber is provided with a quantity of heat, as necessary, to effect secondary combustion of the exhaust gases and particulates by means of an auxiliary heat source and the heat generated within the reaction chamber is stored in the individual heat exchange-filter elements during the discharge of exhaust gases therethrough from the reaction chamber and this heat is then transferred to the inflowing volume of the exhaust gases so that, in effect, exhaust gas is discharged from the device at substantially the same temperature as it was during its inlet into the device from the engine.

  2. Filters for radioactive liquid wastes

    International Nuclear Information System (INIS)

    Koshiba, Yukihiko; Kawashima, Akio

    1980-01-01

    In the crud generated in the reactor cooling water for nuclear power plants, iron oxides (hematite and magnetite) are contained as the main components, and also Co, Mn, Fe, Cr exist as radioactive nuclides. A new filter to separate these cruds, nuclepore membrane filter (NPMF), was investigated for its adaptability, and has been adopted as a practical filter for radioactive liquid wastes. The NPMF has such features as the possibility of complete automation of operation, no generation of secondary wastes, and easy maintenance, because the NPMF has uniform circular holes in poly-carbonate thin films, and shows the properties of stable filtering of particulates, capability of back washing, and others. The elements mounted in a practical system have such construction that the membrane is cut in the form of doughnut, and sandwiched with 100 mesh polyester nets (spacer); the obtained unit filter (cassette) is mounted on the stackable plate of the same size; and 80 pieces of this cassette are formed in a filter of 4 m 2 filtering area. The performance varies with the properties of suspended matters and the turbidity of wastes. For example, the filtered liquid of 0.1 ppm or less can be obtained when the 1 μm filter material is used to treat the liquid waste containing 1 to 100 ppm suspended matters. Usually back washed water is produced by about 1/100 of treated liquid wastes. The lifetime of the membrane is expected to be 1 or 2 years if crud is the main component. (Wakatsuki, Y.)

  3. Cryptosporidium: A Guide to Water Filters

    Science.gov (United States)

    ... Tap Water Many but not all available home water filters remove Cryptosporidium . Some filter designs are more suitable for removal of Cryptosporidium than others. Filters that have the words "reverse osmosis" on the label protect against Cryptosporidium . Some other ...

  4. Text-Fabric

    NARCIS (Netherlands)

    Roorda, Dirk

    2016-01-01

    Text-Fabric is a Python3 package for Text plus Annotations. It provides a data model, a text file format, and a binary format for (ancient) text plus (linguistic) annotations. The emphasis of this all is on: data processing; sharing data; and contributing modules. A defining characteristic is that

  5. PIGMI mechanical fabrication

    International Nuclear Information System (INIS)

    Hart, V.E.

    1976-01-01

    A prime goal of the mechanical design effort associated with the PIGMI (Pion Generator for Medical Irradiations) program is to investigate new materials and fabrication techniques in an effort to obtain increased machine efficiency and reliability at a reasonable cost. The following discussion deals with the modeling program that LASL is pursuing for 450-MHz and 1350-MHz PIGMI development. (author)

  6. Micromechanical Structures Fabrication; FINAL

    International Nuclear Information System (INIS)

    Rajic, S

    2001-01-01

    Work in materials other than silicon for MEMS applications has typically been restricted to metals and metal oxides instead of more ''exotic'' semiconductors. However, group III-V and II-VI semiconductors form a very important and versatile collection of material and electronic parameters available to the MEMS and MOEMS designer. With these materials, not only are the traditional mechanical material variables (thermal conductivity, thermal expansion, Young's modulus, etc.) available, but also chemical constituents can be varied in ternary and quaternary materials. This flexibility can be extremely important for both friction and chemical compatibility issues for MEMS. In addition, the ability to continually vary the bandgap energy can be particularly useful for many electronics and infrared detection applications. However, there are two major obstacles associated with alternate semiconductor material MEMS. The first issue is the actual fabrication of non-silicon micro-devices and the second impediment is communicating with these novel devices. We have implemented an essentially material independent fabrication method that is amenable to most group III-V and II-VI semiconductors. This technique uses a combination of non-traditional direct write precision fabrication processes such as diamond turning, ion milling, laser ablation, etc. This type of deterministic fabrication approach lends itself to an almost trivial assembly process. We also implemented a mechanical, electrical, and optical self-aligning hybridization technique for these alternate-material MEMS substrates

  7. Fabrication activity for nanophotonics

    DEFF Research Database (Denmark)

    Malureanu, Radu; Chung, Il-Sug; Carletti, Luca

    We present the fabrication and characterization of new structures and materials to be used in nanophotonics. The first structure presented is a fractal metallic metasurface designed to be used as a high-sensitivity sensor for 810nm wavelength. A second structure is a high index contrast grating...

  8. Synthesis of highly integrated optical network based on microdisk-resonator add-drop filters in silicon-on-insulator technology

    Science.gov (United States)

    Kaźmierczak, Andrzej; Dortu, Fabian; Giannone, Domenico; Bogaerts, Wim; Drouard, Emmanuel; Rojo-Romeo, Pedro; Gaffiot, Frederic

    2009-10-01

    We analyze a highly compact optical add-drop filter topology based on a pair of microdisk resonators and a bus waveguide intersection. The filter is further assessed on an integrated optical 4×4 network for optical on-chip communication. The proposed network structure, as compact as 50×50 μm, is fabricated in a CMOS-compatible process on a silicon-on-insulator (SOI) substrate. Finally, the experimental results demonstrate the proper operation of the fabricated devices.

  9. Simplified design of filter circuits

    CERN Document Server

    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

  10. High flow ceramic pot filters

    OpenAIRE

    van Halem, D.; van der Laan, H.; Soppe, A. I.A.; Heijman, S.G.J.

    2017-01-01

    Ceramic pot filters are considered safe, robust and appropriate technologies, but there is a general consensus that water revenues are limited due to clogging of the ceramic element. The objective of this study was to investigate the potential of high flow ceramic pot filters to produce more water without sacrificing their microbial removal efficacy. High flow pot filters, produced by increasing the rice husk content, had a higher initial flow rate (6–19 L h−1), but initial LRVs for E. coli o...

  11. Face Recognition using Gabor Filters

    Directory of Open Access Journals (Sweden)

    Sajjad MOHSIN

    2011-01-01

    Full Text Available An Elastic Bunch Graph Map (EBGM algorithm is being proposed in this research paper that successfully implements face recognition using Gabor filters. The proposed system applies 40 different Gabor filters on an image. As aresult of which 40 images with different angles and orientation are received. Next, maximum intensity points in each filtered image are calculated and mark them as Fiducial points. The system reduces these points in accordance to distance between them. The next step is calculating the distances between the reduced points using distance formula. At last, the distances are compared with database. If match occurs, it means that the image is recognized.

  12. Remotely operated top loading filter housing

    International Nuclear Information System (INIS)

    Ross, M.J.; Carter, J.A.

    1989-01-01

    A high-efficiency particulate air (HEPA) filter system was developed for the Fuel Processing Facility at the Idaho Chemical Processing Plant. The system utilizes commercially available HEPA filters and allows in-cell filters to be maintained using operator-controlled remote handling equipment. The remote handling tasks include transport of filters before and after replacement, removal and replacement of the filter from the housing, and filter containment

  13. Concrete ensemble Kalman filters with rigorous catastrophic filter divergence.

    Science.gov (United States)

    Kelly, David; Majda, Andrew J; Tong, Xin T

    2015-08-25

    The ensemble Kalman filter and ensemble square root filters are data assimilation methods used to combine high-dimensional, nonlinear dynamical models with observed data. Ensemble methods are indispensable tools in science and engineering and have enjoyed great success in geophysical sciences, because they allow for computationally cheap low-ensemble-state approximation for extremely high-dimensional turbulent forecast models. From a theoretical perspective, the dynamical properties of these methods are poorly understood. One of the central mysteries is the numerical phenomenon known as catastrophic filter divergence, whereby ensemble-state estimates explode to machine infinity, despite the true state remaining in a bounded region. In this article we provide a breakthrough insight into the phenomenon, by introducing a simple and natural forecast model that transparently exhibits catastrophic filter divergence under all ensemble methods and a large set of initializations. For this model, catastrophic filter divergence is not an artifact of numerical instability, but rather a true dynamical property of the filter. The divergence is not only validated numerically but also proven rigorously. The model cleanly illustrates mechanisms that give rise to catastrophic divergence and confirms intuitive accounts of the phenomena given in past literature.

  14. Photoluminescent properties of LiSrxBa1-xPO4:RE3+ (RE = Sm3+, Eu3+) f-f transition phosphors

    International Nuclear Information System (INIS)

    Tu Dong; Liang Yujun; Liu Rong; Cheng Zheng; Yang Fan; Yang Wenlong

    2011-01-01

    Highlights: → Novel phosphors LiSr x Ba 1-x PO 4 : Sm 3+ and LiSr x Ba 1-x PO 4 : Eu 3+ have been synthesized by solid-state reaction method. → The LiSr x Ba 1-x PO 4 : Sm 3+ and LiSr x Ba 1-x PO 4 : Eu 3+ phosphors may be potential f-f transition phosphors used in LED. → The emission intensity of the LiSr x Ba 1-x PO 4 : Sm 3+ and LiSr x Ba 1-x PO 4 : Eu 3+ phosphors can be enhanced by increasing the value of x. - Abstract: Rare-earth ions (Sm 3+ or Eu 3+ ) doped LiSr x Ba 1-x PO 4 (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0) f-f transition phosphor powders were prepared by a high temperature solid-state reaction. The resulted phosphors were characterized by X-ray diffraction (XRD) and photoluminescence (PL) spectroscopy. The results of XRD indicate that the phase structure of the sample changes from LiBaPO 4 to LiSrPO 4 when x changes from 0 to 1.0. The excitation spectra indicate that only direct excitation of rare earth ions (Sm 3+ or Eu 3+ ) can be observed. The doped rare earth ions show their characteristic emission in LiSr x Ba 1-x PO 4 , i.e., Eu 3+5 D 0 - 7 F J (J = 0, 1, 2, 3, 4), Sm 3+4 G 5/2 → 6 H J (J = 5/2, 7/2, 9/2, 11/2), respectively. The dependence of the emission intensities of the LiSr x Ba 1-x PO 4 :Sm 3+ and LiSr x Ba 1-x PO 4 :Eu 3+ phosphors on the x value and Ln 3+ (Ln 3+ = Sm 3+ , Eu 3+ ) concentration is also investigated.

  15. Optical filter finesses enhancement based on nested coupled cavities and active medium

    Science.gov (United States)

    Adib, George A.; Sabry, Yasser M.; Khalil, Diaa

    2016-04-01

    Optical filters with relatively large FSR and narrow linewidth are simultaneously needed for different applications. The ratio between the FSR and the 3-dB linewidth is given by finesse of the filter, which is solely determined by the different energy loss mechanisms limited by the technology advancement. In this work, we present a novel coupled-cavity configuration embedding an optical filter and a gain medium; allowing an overall finesse enhancement and simultaneous FSR and 3-dB linewidth engineering beyond the technological limits of the filter fabrication method. The configuration consists of two resonators. An active ring resonator comprises an optical gain medium and a passive resonator. In one configuration, the optical filter is the passive resonator itself. In a second configuration, the passive resonator is another ring resonator that embeds the optical filter. The presented configurations using a semiconductor optical amplifier are applied one time to a mechanically Fabry-Perot filter in the first presented configuration; and a second time to a fiber ring filter in the second presented configuration. The mechanical filter has an original 3-dB linewidth of 1nm and an FSR that is larger than 100nm while the enhanced linewidth is about 0.3nm. The fiber ring filter length is 4 m and directional coupler ratios of 90/10corresponding to a 3-dBlinewidth of about 4MHz and an FSR of 47 MHz. The enhanced 3- dBlinewidth of the overall filter configuration is 200kHz, demonstrating finesse enhancement up to20 times the original finesse of the filter.

  16. Vapour HF release of airgap-based UV-visible optical filters

    NARCIS (Netherlands)

    Ghaderi, M.; Ayerden, N.P.; De Graaf, G.; Wolffenbuttel, R.F.

    2015-01-01

    The design and CMOS-compatible fabrication of airgap-based optical filters in a surface micromachining process with sacrificial release using thevapour phase is presented. An airgap-dielectric layer combination offers a higher refractive index contrast, as compared to the conventional

  17. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, BAGHOUSE FILTRATION PRODUCTS, TETRATEC PTFE PRODUCTS, TETRATEX 6212 FILTER SAMPLE

    Science.gov (United States)

    Baghouse filtration products (BFPs) were evaluated by the Air Pollution Control Technology (APCT) Verification Center. The performance factor verified was the mean outlet particle concentration for the filter fabric as a function of the size of those particles equal to and smalle...

  18. Multiterminal semiconductor/ferromagnet probes for spin-filter scanning tunneling microscopy

    NARCIS (Netherlands)

    Vera Marun, I.J.; Jansen, R.

    2009-01-01

    We describe the fabrication of multiterminal semiconductor/ferromagnet probes for a new technique to study magnetic nanostructures: spin-filter scanning tunneling microscopy. We describe the principle of the technique, which is based on spin-polarized tunneling and subsequent analysis of the spin

  19. Status report, canister fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Claes-Goeran; Eriksson, Peter; Westman, Marika [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Emilsson, Goeran [CSM Materialteknik AB, Linkoeping (Sweden)

    2004-06-01

    The report gives an account of the development of material and fabrication technology for copper canisters with cast inserts during the period from 2000 until the start of 2004. The engineering design of the canister and the choice of materials in the constituent components described in previous status reports have not been significantly changed. In the reference canister, the thickness of the copper shell is 50 mm. Fabrication of individual components with a thinner copper thickness is done for the purpose of gaining experience and evaluating fabrication and inspection methods for such canisters. As a part of the development of cast inserts, computer simulations of the casting processes and techniques used at the foundries have been performed for the purpose of optimizing the material properties. These properties have been evaluated by extensive tensile testing and metallographic inspection of test material taken from discs cut at different points along the length of the inserts. The testing results exhibit a relatively large spread. Low elongation values in certain tensile test specimens are due to the presence of poorly formed graphite, porosities, slag or other casting defects. It is concluded in the report that it will not be possible to avoid some presence of observed defects in castings of this size. In the deep repository, the inserts will be exposed to compressive loading and the observed defects are not critical for strength. An analysis of the strength of the inserts and formulation of relevant material requirements must be based on a statistical approach with probabilistic calculations. This work has been initiated and will be concluded during 2004. An initial verifying compression test of a canister in an isostatic press has indicated considerable overstrength in the structure. Seamless copper tubes are fabricated by means of three methods: extrusion, pierce and draw processing, and forging. It can be concluded that extrusion tests have revealed a

  20. Status report, canister fabrication

    International Nuclear Information System (INIS)

    Andersson, Claes-Goeran; Eriksson, Peter; Westman, Marika; Emilsson, Goeran

    2004-06-01

    The report gives an account of the development of material and fabrication technology for copper canisters with cast inserts during the period from 2000 until the start of 2004. The engineering design of the canister and the choice of materials in the constituent components described in previous status reports have not been significantly changed. In the reference canister, the thickness of the copper shell is 50 mm. Fabrication of individual components with a thinner copper thickness is done for the purpose of gaining experience and evaluating fabrication and inspection methods for such canisters. As a part of the development of cast inserts, computer simulations of the casting processes and techniques used at the foundries have been performed for the purpose of optimizing the material properties. These properties have been evaluated by extensive tensile testing and metallographic inspection of test material taken from discs cut at different points along the length of the inserts. The testing results exhibit a relatively large spread. Low elongation values in certain tensile test specimens are due to the presence of poorly formed graphite, porosities, slag or other casting defects. It is concluded in the report that it will not be possible to avoid some presence of observed defects in castings of this size. In the deep repository, the inserts will be exposed to compressive loading and the observed defects are not critical for strength. An analysis of the strength of the inserts and formulation of relevant material requirements must be based on a statistical approach with probabilistic calculations. This work has been initiated and will be concluded during 2004. An initial verifying compression test of a canister in an isostatic press has indicated considerable overstrength in the structure. Seamless copper tubes are fabricated by means of three methods: extrusion, pierce and draw processing, and forging. It can be concluded that extrusion tests have revealed a

  1. Regenerable Carbon Filter, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A Regenerable Carbon Filter (RCF) is proposed for the removal of carbonaceous particulate matter produced in Environmental Control and Life Support (ECLS) processes....

  2. Fremont Tree-Well Filter

    Science.gov (United States)

    Information about the SFBWQP Fremont Tree-Well Filter Spine project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  3. Buffers and vegetative filter strips

    Science.gov (United States)

    Matthew J. Helmers; Thomas M. Isenhart; Michael G. Dosskey; Seth M. Dabney

    2008-01-01

    This chapter describes the use of buffers and vegetative filter strips relative to water quality. In particular, we primarily discuss the herbaceous components of the following NRCS Conservation Practice Standards.

  4. Design and Fabrication of Porous Yttria-Stabilized Zirconia Ceramics for Hot Gas Filtration Applications

    Science.gov (United States)

    Shahini, Shayan

    Hot gas filtration has received growing attention in a variety of applications over the past few years. Yttria-stabilized zirconia (YSZ) is a promising candidate for such an application. In this study, we fabricated disk-type porous YSZ filters using the pore forming procedure, in which poly methyl methacrylate (PMMA) was used as the pore-forming agent. After fabricating the pellets, we characterized them to determine their potential for application as gas filters. We investigated the effect of sintering temperature, polymer particle size, and polymer-to-ceramic ratio on the porosity, pore size, gas permeability, and Vickers hardness of the sintered pellets. Furthermore, we designed two sets of experiments to investigate the robustness of the fabricated pellets--i.e., cyclic heating/cooling and high temperature exposure. This study ushers in a robust technique to fabricate such porous ceramics, which have the potential to be utilized in hot gas filtration.

  5. Stabilization of Cs/Re trapping filters using magnesium phosphate ceramics

    International Nuclear Information System (INIS)

    Jae Hwan Yang; Jin Myeong Shin; Chang Hwa Lee; Chul Min Heo; Min Ku Jeon; Kweon Ho Kang

    2013-01-01

    The present study a promising method for stabilizing spent filters trapping cesium and technetium by using magnesium phosphate ceramics. Simulated spent filters were fabricated by vaporizing nonradioactive cesium and rhenium (a surrogate of Tc) through the voloxidizer. In order to reveal the characteristics of spent filters, phase structures and thermal stability were analyzed by using X-ray diffraction (XRD), X-ray photoelectron spectroscopy, and thermogravimetric analysis techniques. Waste forms were fabricated by crushing spent filters and mixing them with magnesium oxide and potassium phosphate. Characterizations of the waste forms were performed by the analyses of compressive strength, apparent porosity, XRD, and scanning electron microscopy. The waste forms showed the excellent mechanical property compared with that of ordinary Portland cement, with the highest compressive strength of 38.1 MPa in the sample with 30 wt% of Cs-filter. Microstructural analysis suggests that waste materials are encapsulated by the binding matrix composed of magnesium potassium phosphate. The results of characterization suggest that fabricating a sound and durable waste form is possible with magnesium phosphate ceramics. (author)

  6. Ion trajectories quadrupole mass filters

    International Nuclear Information System (INIS)

    Ursu, D.; Lupsa, N.; Muntean, F.

    1994-01-01

    The present paper aims at bringing some contributions to the understanding of ion motion in quadrupole mass filters. The theoretical treatment of quadrupole mass filter is intended to be a concise derivation of the important physical relationships using Mathieu functions. A simple iterative method of numerical computation has been used to simulate ion trajectories in an ideal quadrupole field. Finally, some examples of calculation are presented with the aid of computer graphics. (Author) 14 Figs., 1 Tab., 20 Refs

  7. Filter indexing for spectrophotometer system

    International Nuclear Information System (INIS)

    Chamran, M.M.; Scott, L.B.; Williams, P.B.

    1982-01-01

    A spectrophotometer system has an optical system for transmitting a beam from a source at select wavelengths onto a detector. A plurality of filters are positioned in a tray. A stepper mechanism indexes the tray along a path. A microcomputer controls the stepper mechanism and the optical system. The wavelength is successively changed over a range, the tray is indexed to move a select filter into the beam at a predetermined wavelength and the changing is discontinued during indexing

  8. New iodine filter pack design

    International Nuclear Information System (INIS)

    Blackbee, B.A.

    1977-10-01

    To enable Naval Emergency Monitoring Teams to fulfil their role in the field it was necessary to locate or design a replacement filter pack for the collection of radioactive iodine air samples. Collaboration with the Berkeley Laboratories of the Central Electricity Generating Board provided the necessary starting point for a suitable type of package. Further development by NGTE (West Drayton) yielded the improved filter pack which is the subject of this memorandum. (author)

  9. Stochastic processes and filtering theory

    CERN Document Server

    Jazwinski, Andrew H

    1970-01-01

    This unified treatment of linear and nonlinear filtering theory presents material previously available only in journals, and in terms accessible to engineering students. Its sole prerequisites are advanced calculus, the theory of ordinary differential equations, and matrix analysis. Although theory is emphasized, the text discusses numerous practical applications as well.Taking the state-space approach to filtering, this text models dynamical systems by finite-dimensional Markov processes, outputs of stochastic difference, and differential equations. Starting with background material on probab

  10. Radiosurgery with flattening-filter-free techniques in the treatment of brain metastases. Plan comparison and early clinical evaluation

    International Nuclear Information System (INIS)

    Rieber, J.; Tonndorf-Martini, E.; Schramm, O.; Rhein, B.; Stefanowicz, S.; Lindel, K.; Debus, J.; Rieken, S.; Kappes, J.; Hoffmann, H.

    2016-01-01

    Radiosurgical treatment of brain metastases is well established in daily clinical routine. Utilization of flattening-filter-free beams (FFF) may allow for more rapid delivery of treatment doses and improve clinical comfort. Hence, we compared plan quality and efficiency of radiosurgery in FFF mode to FF techniques. Between November 2014 and June 2015, 21 consecutive patients with 25 brain metastases were treated with stereotactic radiosurgery (SRS) in FFF mode. Brain metastases received dose-fractionation schedules of 1 x 20 Gy or 1 x 18 Gy, delivered to the conformally enclosing 80 % isodose. Three patients with critically localized or large (>3 cm) brain metastases were treated with 6 x 5 Gy. Plan quality and efficiency were evaluated by analyzing conformity, dose gradients, dose to healthy brain tissue, treatment delivery time, and number of monitor units. FFF plans were compared to those using the FF method, and early clinical outcome and toxicity were assessed. FFF mode resulted in significant reductions in beam-on time (p [de

  11. Fabricating microfluidic valve master molds in SU-8 photoresist

    Science.gov (United States)

    Dy, Aaron J.; Cosmanescu, Alin; Sluka, James; Glazier, James A.; Stupack, Dwayne; Amarie, Dragos

    2014-05-01

    Multilayer soft lithography has become a powerful tool in analytical chemistry, biochemistry, material and life sciences, and medical research. Complex fluidic micro-circuits require reliable components that integrate easily into microchips. We introduce two novel approaches to master mold fabrication for constructing in-line micro-valves using SU-8. Our fabrication techniques enable robust and versatile integration of many lab-on-a-chip functions including filters, mixers, pumps, stream focusing and cell-culture chambers, with in-line valves. SU-8 created more robust valve master molds than the conventional positive photoresists used in multilayer soft lithography, but maintained the advantages of biocompatibility and rapid prototyping. As an example, we used valve master molds made of SU-8 to fabricate PDMS chips capable of precisely controlling beads or cells in solution.

  12. Fabricating microfluidic valve master molds in SU-8 photoresist

    International Nuclear Information System (INIS)

    Dy, Aaron J; Cosmanescu, Alin; Sluka, James; Glazier, James A; Amarie, Dragos; Stupack, Dwayne

    2014-01-01

    Multilayer soft lithography has become a powerful tool in analytical chemistry, biochemistry, material and life sciences, and medical research. Complex fluidic micro-circuits require reliable components that integrate easily into microchips. We introduce two novel approaches to master mold fabrication for constructing in-line micro-valves using SU-8. Our fabrication techniques enable robust and versatile integration of many lab-on-a-chip functions including filters, mixers, pumps, stream focusing and cell-culture chambers, with in-line valves. SU-8 created more robust valve master molds than the conventional positive photoresists used in multilayer soft lithography, but maintained the advantages of biocompatibility and rapid prototyping. As an example, we used valve master molds made of SU-8 to fabricate PDMS chips capable of precisely controlling beads or cells in solution. (technical note)

  13. A quantum extended Kalman filter

    International Nuclear Information System (INIS)

    Emzir, Muhammad F; Woolley, Matthew J; Petersen, Ian R

    2017-01-01

    In quantum physics, a stochastic master equation (SME) estimates the state (density operator) of a quantum system in the Schrödinger picture based on a record of measurements made on the system. In the Heisenberg picture, the SME is a quantum filter. For a linear quantum system subject to linear measurements and Gaussian noise, the dynamics may be described by quantum stochastic differential equations (QSDEs), also known as quantum Langevin equations, and the quantum filter reduces to a so-called quantum Kalman filter. In this article, we introduce a quantum extended Kalman filter (quantum EKF), which applies a commutative approximation and a time-varying linearization to systems of nonlinear QSDEs. We will show that there are conditions under which a filter similar to a classical EKF can be implemented for quantum systems. The boundedness of estimation errors and the filtering problem with ‘state-dependent’ covariances for process and measurement noises are also discussed. We demonstrate the effectiveness of the quantum EKF by applying it to systems that involve multiple modes, nonlinear Hamiltonians, and simultaneous jump-diffusive measurements. (paper)

  14. A quantum extended Kalman filter

    Science.gov (United States)

    Emzir, Muhammad F.; Woolley, Matthew J.; Petersen, Ian R.

    2017-06-01

    In quantum physics, a stochastic master equation (SME) estimates the state (density operator) of a quantum system in the Schrödinger picture based on a record of measurements made on the system. In the Heisenberg picture, the SME is a quantum filter. For a linear quantum system subject to linear measurements and Gaussian noise, the dynamics may be described by quantum stochastic differential equations (QSDEs), also known as quantum Langevin equations, and the quantum filter reduces to a so-called quantum Kalman filter. In this article, we introduce a quantum extended Kalman filter (quantum EKF), which applies a commutative approximation and a time-varying linearization to systems of nonlinear QSDEs. We will show that there are conditions under which a filter similar to a classical EKF can be implemented for quantum systems. The boundedness of estimation errors and the filtering problem with ‘state-dependent’ covariances for process and measurement noises are also discussed. We demonstrate the effectiveness of the quantum EKF by applying it to systems that involve multiple modes, nonlinear Hamiltonians, and simultaneous jump-diffusive measurements.

  15. Planar Superconducting Millimeter-Wave/Terahertz Channelizing Filter

    Science.gov (United States)

    Ehsan, Negar; U-yen, Kongpop; Brown, Ari; Hsieh, Wen-Ting; Wollack, Edward; Moseley, Samuel

    2013-01-01

    This innovation is a compact, superconducting, channelizing bandpass filter on a single-crystal (0.45 m thick) silicon substrate, which operates from 300 to 600 GHz. This device consists of four channels with center frequencies of 310, 380, 460, and 550 GHz, with approximately 50-GHz bandwidth per channel. The filter concept is inspired by the mammalian cochlea, which is a channelizing filter that covers three decades of bandwidth and 3,000 channels in a very small physical space. By using a simplified physical cochlear model, and its electrical analog of a channelizing filter covering multiple octaves bandwidth, a large number of output channels with high inter-channel isolation and high-order upper stopband response can be designed. A channelizing filter is a critical component used in spectrometer instruments that measure the intensity of light at various frequencies. This embodiment was designed for MicroSpec in order to increase the resolution of the instrument (with four channels, the resolution will be increased by a factor of four). MicroSpec is a revolutionary wafer-scale spectrometer that is intended for the SPICA (Space Infrared Telescope for Cosmology and Astrophysics) Mission. In addition to being a vital component of MicroSpec, the channelizing filter itself is a low-resolution spectrometer when integrated with only an antenna at its input, and a detector at each channel s output. During the design process for this filter, the available characteristic impedances, possible lumped element ranges, and fabrication tolerances were identified for design on a very thin silicon substrate. Iterations between full-wave and lumped-element circuit simulations were performed. Each channel s circuit was designed based on the availability of characteristic impedances and lumped element ranges. This design was based on a tabular type bandpass filter with no spurious harmonic response. Extensive electromagnetic modeling for each channel was performed. Four channels

  16. A capacitive DAC with custom 3-D 1-fF MOM unit capacitors optimized for fast-settling routing in high speed SAR ADCs

    International Nuclear Information System (INIS)

    Chen Chixiao; Xiang Jixuan; Chen Huabin; Xu Jun; Ye Fan; Li Ning; Ren Junyan

    2015-01-01

    Asynchronous successive approximation register (SAR) analog-to-digital converters (ADC) feature high energy efficiency but medium performance. From the point of view of speed, the key bottleneck is the unit capacitor size. In this paper, a small size three-dimensional (3-D) metal—oxide—metal (MOM) capacitor is proposed. The unit capacitor has a capacitance of 1-fF. It shapes as an umbrella, which is designed for fast settling consideration. A comparison among the proposed capacitor with other 3-D MOM capacitors is also given in the paper. To demonstrate the effectiveness of the MOM capacitor, a 6-b capacitive DAC is implemented in TSMC 1P9M 65 nm LP CMOS technology. The DAC consumes a power dissipation of 0.16 mW at the rate of 100 MS/s, excluding a source-follower based output buffer. Static measurement result shows that INL is less than ±1 LSB and DNL is less than ±0.5 LSB. In addition, a 100 MS/s 9-bit SAR ADC with the proposed 3-D capacitor is simulated. (paper)

  17. Alternating current line-filter based on electrochemical capacitor utilizing template-patterned graphene.

    Science.gov (United States)

    Wu, Zhenkun; Li, Liyi; Lin, Ziyin; Song, Bo; Li, Zhuo; Moon, Kyoung-Sik; Wong, Ching-Ping; Bai, Shu-Lin

    2015-06-17

    Aluminum electrolytic capacitors (AECs) are widely used for alternating current (ac) line-filtering. However, their bulky size is becoming more and more incompatible with the rapid development of portable electronics. Here we report a scalable process to fabricate miniaturized graphene-based ac line-filters on flexible substrates at room temperature. In this work, graphene oxide (GO) is reduced by patterned metal interdigits at room temperature and used directly as the electrode material. The as-fabricated device shows a phase angle of -75.4° at 120 Hz with a specific capacitance of 316 µF/cm(2) and a RC time constant of 0.35 ms. In addition, it retains 97.2% of the initial capacitance after 10000 charge/discharge cycles. These outstanding performance characteristics of our device demonstrate its promising to replace the conventional AECs for ac line filtering.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-06-01

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

  19. Experience with three percutaneous vena cava filters

    International Nuclear Information System (INIS)

    McCowan, T.C.; Ferris, E.J.; Harshfield, D.L.; Hassell, D.R.; Baker, M.L.

    1987-01-01

    Twenty-one Kimray-Greenfield, 33 bird's nest, and 19 Amplatz vena cava filters were placed percutaneously. The Kimray-Greenfield filter was the most difficult to insert. The major problem was the insertion site, which required venipuncture with a 24-F catheter. Minor hemorrhage was frequent, and femoral vein thrombosis occurred in four patients. No migration, caval thrombosis, or pulmonary emboli were seen after Kimray-Greenfield filter placement. The bird's nest filter was relatively easy to insert, although in two cases the filter prongs could not be adequately seated in the wall of the inferior vena cava. Three patients with bird's nest filters had thrombosis below the filter, and three filters migrated to the heart. One migrated filter could not be removed. One patient had multiple small pulmonary emboli at autopsy. No other pulmonary emboli after filter placement were noted. The Amplatz filter was the easiest of the three filters to insert. Only one patient with an Amplatz filter had thrombosis of the vena cava below the filter. No filter migrations were documented, and no recurrent pulmonary emboli were found on clinical or radiologic follow-up. The Amplatz vena cava filter is easier to place than percutaneous Kimray-Greenfield or bird's nest filters, has a low complication rate, and has proven to be clinically effective in preventing pulmonary emboli

  20. Automated breeder fuel fabrication

    International Nuclear Information System (INIS)

    Goldmann, L.H.; Frederickson, J.R.

    1983-01-01

    The objective of the Secure Automated Fabrication (SAF) Project is to develop remotely operated equipment for the processing and manufacturing of breeder reactor fuel pins. The SAF line will be installed in the Fuels and Materials Examination Facility (FMEF). The FMEF is presently under construction at the Department of Energy's (DOE) Hanford site near Richland, Washington, and is operated by the Westinghouse Hanford Company (WHC). The fabrication and support systems of the SAF line are designed for computer-controlled operation from a centralized control room. Remote and automated fuel fabriction operations will result in: reduced radiation exposure to workers; enhanced safeguards; improved product quality; near real-time accountability, and increased productivity. The present schedule calls for installation of SAF line equipment in the FMEF beginning in 1984, with qualifying runs starting in 1986 and production commencing in 1987. 5 figures

  1. OPO fabric decontamination

    International Nuclear Information System (INIS)

    Severa, J.; Bar, J.; Grujbar, V.

    1978-01-01

    Samples of five polypropylene-based man-made fabrics were studied with regard to the degree of contamination and possibilities of decontamination in order to assess their suitability as material for protective clothing in the nuclear industry. The contamination degree of the fabrics in an aqueous solution of a fission product mixture was found to be low. Soaking in a mixture of the Sapon detergent and sodium hexametaphosphate at a concentration of both materials of 1 g/l with subsequent washing in a solution of the Zenit detergent at a concentration of 3 g/l was suggested as the most suitable decontamination procedure. It reduces the initial contamination by almost 99%. (Z.M.)

  2. Sensory pollution from bag-type fiberglass ventilation filters: Conventional filter compared with filters containing various amounts of activated carbon

    DEFF Research Database (Denmark)

    Bekö, Gabriel; Fadeyi, M.O.; Clausen, Geo

    2009-01-01

    filter and three modifications of a bag-type fiberglass combination filter: the "Heavy" corresponded to a commercially available filter containing 400 g of carbon per square meter of filter area, the "Medium" contained half as much carbon (200 g/m(2)), and the "Light" contained a quarter as much carbon...

  3. Intentionally fabricated autobiographical memories

    OpenAIRE

    Justice, LV; Morrison, CM; Conway, MA

    2017-01-01

    Participants generated both autobiographical memories (AMs) that they believed to be true and intentionally fabricated autobiographical memories (IFAMs). Memories were constructed while a concurrent memory load (random 8-digit sequence) was held in mind or while there was no concurrent load. Amount and accuracy of recall of the concurrent memory load was reliably poorer following generation of IFAMs than following generation of AMs. There was no reliable effect of load on memory generation ti...

  4. Colored fused filament fabrication

    OpenAIRE

    Song, Haichuan; Lefebvre, Sylvain

    2017-01-01

    Filament fused fabrication is the method of choice for printing 3D models at low cost, and is the de-facto standard for hobbyists, makers and schools. Unfortunately, filament printers cannot truly reproduce colored objects. The best current techniques rely on a form of dithering exploiting occlusion, that was only demonstrated for shades of two base colors and that behaves differently depending on surface slope. We explore a novel approach for 3D printing colored objects, capable of creating ...

  5. Plasmonic coaxial Fabry-Pérot nanocavity color filter

    Science.gov (United States)

    Si, G. Y.; Leong, E. S. P.; Danner, A. J.; Teng, J. H.

    2010-08-01

    Plamonic coaxial structures have drawn considerable attetion recently because of their unique properties. They exhibit different mechanisms of extraordinary optical transmission observed from subwavelength holes and they can support localized Fabry-Pérot plasmon modes. In this work, we experimentally demonstrate color filters based on coaxial structures fabricated in optically thick metallic films. Using nanogaps with different apertures from 160 nm down to only 40 nm, we show varying color outputs when the annular aperture arrays are illuminated with a broadband light source. Effective color-filter function is demonstrated in the optical regime. Different color outputs are observed and optical spectra are measured. In such structures, it is the propagating mode playing an important role rather than the evanescent. Resonances depend strongly on ring apertures, enabling devices with tunability of output colors using simple geometry control.

  6. Optical Microresonators Theory, Fabrication, and Applications

    CERN Document Server

    Heebner, John; Ibrahim, Tarek

    2008-01-01

    This book explains why microresonators came to be important components in the photonic toolbox. While functionally similar to the Fabry-Perot, microring resonators offer a planar nature which is naturally compatible with monolithic microfabrication technologies. In these chapters lie the principles required to characterize, design, construct, and implement microresonators as lasers, amplifiers, sensors, filters, demultiplexers, switches, routers, and logic gates. Additionally, much like quantum dots and photonic crystals, it will be shown how microresonators offer an alternative method for creating engineerable materials with designer linear and nonlinear responses tailored for advanced functionalities operating at ultrafast speeds and compact scales. This is the first detailed text on the theory, fabrication, and applications of optical microresonators, and will be found useful by both graduate students and researchers. With an emphasis on building intuition with distilled equations and graphical illustratio...

  7. Fabrication and Optoelectrical Properties of IZO/Cu2O Heterostructure Solar Cells by Thermal Oxidation

    Directory of Open Access Journals (Sweden)

    Cheng-Chiang Chen

    2012-01-01

    Full Text Available Indium zinc oxide (IZO/cupper oxide (Cu2O is a nontoxic nature and an attractive all-oxide candidate for low-cost photovoltaic (PV applications. The present paper reports on the fabrication of IZO/Cu2O heterostructure solar cells which the Cu2O layers were prepared by oxidation of Cu thin films deposited on glass substrate. The measured parameters of cells were the short-circuit current (Isc, the open-circuit voltage (Voc, the maximum output power (Pm, the fill factor (FF, and the efficiency (η, which had values of 0.11 mA, 0.136 V, 5.05 μW, 0.338, and 0.56%, respectively, under AM 1.5 illumination.

  8. Advanced fuel fabrication

    International Nuclear Information System (INIS)

    Bernard, H.

    1989-01-01

    This paper deals with the fabrication of advanced fuels, such as mixed oxides for Pressurized Water Reactors or mixed nitrides for Fast Breeder Reactors. Although an extensive production experience exists for the mixed oxides used in the FBR, important work is still needed to improve the theoretical and technical knowledge of the production route which will be introduced in the future European facility, named Melox, at Marcoule. Recently, the feasibility of nitride fuel fabrication in existing commercial oxide facilities was demonstrated in France. The process, based on carbothermic reduction of oxides with subsequent comminution of the reaction product, cold pressing and sintering provides (U, Pu)N pellets with characteristics suitable for irradiation testing. Two experiments named NIMPHE 1 and 2 fabricated in collaboration with ITU, Karlsruhe, involve 16 nitride and 2 carbide pins, operating at a linear power of 45 and 73 kW/m with a smear density of 75-80% TD and a high burn-up target of 15 at%. These experiments are currently being irradiated in Phenix, at Marcoule. (orig.)

  9. Waste to wealth concept: Disposable RGO filter paper for flexible temperature sensor applications

    Science.gov (United States)

    Neella, Nagarjuna; Kedambaimoole, Vaishakh; Gaddam, Venkateswarlu; Nayak, M. M.; Rajanna, K.

    2018-04-01

    We have developed a flexible reduced graphene oxide (RGO) temperature sensor on filter paper based cellulose substrate using vacuum filtration method. One of the most commonly used synthesized methods for RGO thin films is vacuum filtration process. It has several advantages such as simple operation and good controllability. The structural analysis was carried out by FE-SEM, in which the surface morphology images confirm the formation of RGO nanostructures on the filter paper substrate. It was observed that the pores of the filter paper were completely filled with the RGO material during the filtration process, subsequently the formation of continuous RGO thin films. As a results, the RGO films exhibits a piezoresistive property. The resulted RGO based films on the filter paper reveals the semiconducting behavior having sensitivity of 0.278 Ω /°C and negative temperature coefficient (NTC) about -0.00254 Ω/ Ω / °C. Thus, we demonstrate a simplified way for the fabrication of RGO films on filter paper that possesses better and easier measurable macroscopic electrical properties. Our approach is for easy way of electronics, cost-effective and environment friendly fabrication route for flexible conducting graphene films on filter paper. This will enable for the potential applications in flexible electronics in various fields including biomedical, automobile and aerospace engineering.

  10. Design of a micromachined terahertz electromagnetic crystals (EMXT) channel-drop filter on silicon-substrate

    Science.gov (United States)

    Zhou, Kai; Liu, Yong; Si, Liming; Lv, Xin

    2013-08-01

    An integrated 0.5 THz electromagnetic crystals(EMXT) channel-drop filter based on PBG structure is presented in this paper. A channel-drop filter is a device in which a narrow bandwidth is redirected to another "drop" waveguide while other frequencies are unaffected. It's capable of extracting a certain frequency from a continuous spectrum in the bus channel and passing it to the test channel. It has potential applications in photonic integrated circuits, radio astronomy, THz spectroscopy, THz communication and remote sensing radar receiver. PBG structures(or photonic crystals) are periodic structures which possess band gaps, where the electromagnetic wave of certain ranges of frequencies cannot pass through and is reflected. The proposed channel-drop filter consists of input waveguide,output waveguide and PBG structure. The proposed filter is simulated using the finite element method and can be fabricated by micro-electromechanical systems (MEMS) technology,due to its low cost, high performance and high processing precision.The filter operation principle and fabrication process are discussed.The simulation results show its ability to filter the frequency of 496GHz with a linewidth of approximately 4GHz and transmission of 27.2 dB above background.The loss at resonant frequency is less than 1dB considering the thickness and roughness of gold layer required by the MEMS process.The channel drop efficiency is 84%.

  11. Filter-adsorber aging assessment

    Energy Technology Data Exchange (ETDEWEB)

    Winegardner, W.K. [Pacific Northwest Laboratory, Richland, WA (United States)

    1995-02-01

    An aging assessment of high-efficiency particulate (HEPA) air filters and activated carbon gas adsorption units was performed by the Pacific Northwest Laboratory as part of the U.S. Nuclear Regulatory Commission`s (USNRC) Nuclear Plant Aging Research (NPAR) Program. This evaluation of the general process in which characteristics of these two components gradually change with time or use included the compilation of information concerning failure experience, stressors, aging mechanisms and effects, and inspection, surveillance, and monitoring methods (ISMM). Stressors, the agents or stimuli that can produce aging degradation, include heat, radiation, volatile contaminants, and even normal concentrations of aerosol particles and gasses. In an experimental evaluation of degradation in terms of the tensile breaking strength of aged filter media specimens, over forty percent of the samples did not meet specifications for new material. Chemical and physical reactions can gradually embrittle sealants and gaskets as well as filter media. Mechanisms that can lead to impaired adsorber performance are associated with the loss of potentially available active sites as a result of the exposure of the carbon to airborne moisture or volatile organic compounds. Inspection, surveillance, and monitoring methods have been established to observe filter pressure drop buildup, check HEPA filters and adsorbers for bypass, and determine the retention effectiveness of aged carbon. These evaluations of installed filters do not reveal degradation in terms of reduced media strength but that under normal conditions aged media can continue to effectively retain particles. However, this degradation may be important when considering the likelihood of moisture, steam, and higher particle loadings during severe accidents and the fact it is probable that the filters have been in use for an extended period.

  12. Stochastic simulation and robust design optimization of integrated photonic filters

    Directory of Open Access Journals (Sweden)

    Weng Tsui-Wei

    2016-07-01

    Full Text Available Manufacturing variations are becoming an unavoidable issue in modern fabrication processes; therefore, it is crucial to be able to include stochastic uncertainties in the design phase. In this paper, integrated photonic coupled ring resonator filters are considered as an example of significant interest. The sparsity structure in photonic circuits is exploited to construct a sparse combined generalized polynomial chaos model, which is then used to analyze related statistics and perform robust design optimization. Simulation results show that the optimized circuits are more robust to fabrication process variations and achieve a reduction of 11%–35% in the mean square errors of the 3 dB bandwidth compared to unoptimized nominal designs.

  13. Ultra compact triplexing filters based on SOI nanowire AWGs

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Jiashun; An Junming; Zhao Lei; Song Shijiao; Wang Liangliang; Li Jianguang; Wang Hongjie; Wu Yuanda; Hu Xiongwei, E-mail: junming@red.semi.ac.cn [State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

    2011-04-15

    An ultra compact triplexing filter was designed based on a silicon on insulator (SOI) nanowire arrayed waveguide grating (AWG) for fiber-to-the-home FTTH. The simulation results revealed that the design performed well in the sense of having a good triplexing function. The designed SOI nanowire AWGs were fabricated using ultraviolet lithography and induced coupler plasma etching. The experimental results showed that the crosstalk was less than -15 dB, and the 3 dB-bandwidth was 11.04 nm. The peak wavelength output from ports a, c, and b were 1455, 1510 and 1300 nm, respectively, which deviated from our original expectations. The deviation of the wavelength is mainly caused by 45 nm width deviation of the arrayed waveguides during the course of the fabrication process and partly caused by material dispersion. (semiconductor devices)

  14. Ultra compact triplexing filters based on SOI nanowire AWGs

    International Nuclear Information System (INIS)

    Zhang Jiashun; An Junming; Zhao Lei; Song Shijiao; Wang Liangliang; Li Jianguang; Wang Hongjie; Wu Yuanda; Hu Xiongwei

    2011-01-01

    An ultra compact triplexing filter was designed based on a silicon on insulator (SOI) nanowire arrayed waveguide grating (AWG) for fiber-to-the-home FTTH. The simulation results revealed that the design performed well in the sense of having a good triplexing function. The designed SOI nanowire AWGs were fabricated using ultraviolet lithography and induced coupler plasma etching. The experimental results showed that the crosstalk was less than -15 dB, and the 3 dB-bandwidth was 11.04 nm. The peak wavelength output from ports a, c, and b were 1455, 1510 and 1300 nm, respectively, which deviated from our original expectations. The deviation of the wavelength is mainly caused by 45 nm width deviation of the arrayed waveguides during the course of the fabrication process and partly caused by material dispersion. (semiconductor devices)

  15. Ultra compact triplexing filters based on SOI nanowire AWGs

    Science.gov (United States)

    Jiashun, Zhang; Junming, An; Lei, Zhao; Shijiao, Song; Liangliang, Wang; Jianguang, Li; Hongjie, Wang; Yuanda, Wu; Xiongwei, Hu

    2011-04-01

    An ultra compact triplexing filter was designed based on a silicon on insulator (SOI) nanowire arrayed waveguide grating (AWG) for fiber-to-the-home FTTH. The simulation results revealed that the design performed well in the sense of having a good triplexing function. The designed SOI nanowire AWGs were fabricated using ultraviolet lithography and induced coupler plasma etching. The experimental results showed that the crosstalk was less than -15 dB, and the 3 dB-bandwidth was 11.04 nm. The peak wavelength output from ports a, c, and b were 1455, 1510 and 1300 nm, respectively, which deviated from our original expectations. The deviation of the wavelength is mainly caused by 45 nm width deviation of the arrayed waveguides during the course of the fabrication process and partly caused by material dispersion.

  16. Steering and filtering white light with resonant waveguide gratings

    Science.gov (United States)

    Quaranta, Giorgio; Basset, Guillaume; Martin, Olivier J. F.; Gallinet, Benjamin

    2017-08-01

    A novel thin-film single-layer structure based on resonant waveguide gratings (RWGs) allows to engineer selective color filtering and steering of white light. The unit cell of the structure consists of two adjacent finite-length and cross-talking RWGs, where the former acts as in-coupler and the latter acts as out-coupler. The structure is made by only one nano-imprint lithography replication and one thin film layer deposition, making it fully compatible with up-scalable fabrication processes. We characterize a fabricated optical security element designed to work with the flash and the camera of a smartphone in off-axis light steering configuration, where the pattern is revealed only by placing the smartphone in the proper position. Widespread applications are foreseen in a variety of fields, such as multifocal or monochromatic lenses, solar cells, biosensors, security devices and seethrough optical combiners for near-eye displays.

  17. 21 CFR 211.72 - Filters.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Filters. 211.72 Section 211.72 Food and Drugs FOOD... shall not release fibers into such products. Fiber-releasing filters may be used when it is not possible to manufacture such products without the use of these filters. If use of a fiber-releasing filter is...

  18. Decentralized Social Filtering based on Trust

    OpenAIRE

    Olsson, Tomas

    1998-01-01

    This paper describes a decentralised approach to social filtering based on trust between agents in a multiagent system. The social filtering in the proposed approach is built on the interactions between collaborative software agents performing content-based filtering. This means that it uses a mixture of content-based and social filtering and thereby, it takes advantage of both methods.

  19. A class of orthogonal nonrecursive binomial filters.

    Science.gov (United States)

    Haddad, R. A.

    1971-01-01

    The time- and frequency-domain properties of the orthogonal binomial sequences are presented. It is shown that these sequences, or digital filters based on them, can be generated using adders and delay elements only. The frequency-domain behavior of these nonrecursive binomial filters suggests a number of applications as low-pass Gaussian filters or as inexpensive bandpass filters.

  20. Digital notch filter based active damping for LCL filters

    DEFF Research Database (Denmark)

    Yao, Wenli; Yang, Yongheng; Zhang, Xiaobin

    2015-01-01

    . In contrast, the active damping does not require any dissipation elements, and thus has become of increasing interest. As a result, a vast of active damping solutions have been reported, among which multi-loop control systems and additional sensors are necessary, leading to increased cost and complexity....... In this paper, a notch filter based active damping without the requirement of additional sensors is proposed, where the inverter current is employed as the feedback variable. Firstly, a design method of the notch filter for active damping is presented. The entire system stability has then been investigated...... in the z-domain. Simulations and experiments are carried out to verify the proposed active damping method. Both results have confirmed that the notch filter based active damping can ensure the entire system stability in the case of resonances with a good system performance....