Science.gov

Sample records for depolymerizable mandrel technique

  1. Decomposable Mandrel Project. Progress report

    SciTech Connect

    Letts, S.A.; Fearon, E.; Allison, L.; Buckley, S.; Saculla, M.; Cook, R.

    1995-05-08

    We report on our progress in developing a new technology to produce both Nova and NIF scale capsules using a depolymerizable mandrel. In this technique we use poly({alpha}-methylstyrene) (PAMS) beads or shells as mandrels which are overcoated with plasma polymer. The poly({alpha}-methylstyrene) mandrel is then thermally depolymerized to gas phase monomer which diffuses away through the more thermally stable plasma polymer coating, leaving a hollow shell. Since our last report we have concentrated on characterization of the final shell. Starting with PAMS bead mandrels leads to distorted pyrolyzed shells because of thermally induced creep of the CH coating. We found that plasma polymer coatings on hollow shell mandrels shrink isotropically during pyrolysis and maintain sphericity. We are now concentrating our efforts on the use of microencapsulated shells to prepare targets with buried diagnostic layers or inner wall surface texture.

  2. PROGRESS IN 2 mm GLOW DISCHARGE POLYMER MANDREL DEVELOPMENT FOR NIF

    SciTech Connect

    NIKROO,A; BOUSQUET,J; COOK,R; McQUILLAN,B.W; PAGUIO,R; TAKAGI,M

    2003-06-01

    OAK-B135 All planned National Ignition Facility (NIF) capsule targets except machined beryllium require a glow discharge polymer (GDP) mandrel upon which the albator is applied. This mandrel, {approx} 2 mm in diameter, must at least meet if not exceed the symmetry and surface finish requirements of the final capsule. Such mandrels are currently produced by the three-step depolymerizable mandrel technique. The quality of the final mandrel depends upon precise optimization and execution of each of the three steps. They had shown previously that fabrication of a mandrel which met the symmetry and surface finish requirements was feasible using this technique. In this paper they will discuss recent progress towards converting this process into a high yield, production scale process.

  3. COATING AND MANDREL EFFECTS ON FABRICATION OF GLOW DISCHARGE POLYMER NIF SCALE INDIRECT DRIVE CAPSULES

    SciTech Connect

    NIKROO,A; PONTELANDOLFO,JM; CASTILLO,ER

    2002-04-01

    OAK A271 COATING AND MANDREL EFFECTS ON FABRICATION OF GLOW DISCHARGE POLYMER NIF SCALE INDIRECT DRIVE CAPSULES. Targets for the National Ignition Facility (NIF) need to be about 200 {micro}m thick and 2 mm in diameter. These dimensions are well beyond those currently fabricated on a routine basis. They have investigated fabrication of near NIF scale targets using the depolymerizable mandrel technique. Poly-alpha-methylstyrene (PAMS) mandrels, about 2 mm in diameter, of varying qualities were coated with as much as 125 {micro}m of glow discharge polymer (GDP). The surface finish of the final shells was examined using a variety of techniques. A clear dependence of the modal spectrum of final GDP shell on the quality of the initial PAMS mandrels was observed. isolated features were found to be the greatest cause for a shell not meeting the NIF standard.

  4. Mandrel-based patterning: density multiplication techniques for 15nm nodes

    NASA Astrophysics Data System (ADS)

    Bencher, Chris; Dai, Huixiong; Miao, Liyan; Chen, Yongmei; Xu, Ping; Chen, Yijian; Oemardani, Shiany; Sweis, Jason; Wiaux, Vincent; Hermans, Jan; Chang, Li-Wen; Bao, Xinyu; Yi, He; Wong, H.-S. Philip

    2011-04-01

    In many ways, sidewall spacer double patterning has created a new paradigm for lithographic roadmaps. Instead of using lithography as the principal process for generating device features, the role of lithography becomes to generate a mandrel (a pre-pattern) off-of-which one will subsequently replicate patterns with various degrees of density multiplication. Under this new paradigm, the innovativeness of various density multiplication techniques is as critical to the scaling roadmap as the exposure tools themselves. Sidewall spacer double patterning was the first incarnation of mandrel based patterning; adopted quickly in NAND flash where layouts were simple and design space was focused. But today, the use of advanced automated decomposition tools are showing spacer based patterning solutions for very complex logic designs. Future incarnations can involve the use of laminated spacers to create quadruple patterning or by retaining the original mandrel as a method to obtain triple patterning. Directed self-assembly is yet another emerging embodiment of mandrel based patterning, where selfseparating polymers are registered and guided by the physical constraint of a mandrel or by chemical pre-pattern trails formed onto the substrate. In this summary of several bodies of work, we will review several wafer level demonstrations, all of which use various forms of mandrel or stencil based density multiplication including sidewall spacer based double, triple and quadruple patterning techniques for lines, SADP for via multiplication, and some directed self-assembly results all capable of addressing 15nm technology node requirements and below. To address concerns surrounding spacer double patterning design restrictions, we show collaboration results with an EDA partner to demonstrate SADP capability for BEOL routing layers. To show the ultimate realization of SADP, we partner with IMEC on multiple demonstrations of EUV+SADP.

  5. Flexible reusable mandrels

    NASA Technical Reports Server (NTRS)

    Willden, Kurtis S. (Inventor)

    1995-01-01

    A reusable laminate mandrel which is unaffected by extreme temperature changes. The flexible laminate mandrel is comprised of sheets stacked to produce the required configuration, a cover wrap that applies pressure to the mandrel laminate, maintaining the stack cross-section. Then after use, the mandrels can be removed, disassembled, and reused. In the method of extracting the flexible mandrel from one end of a composite stiffener, individual ones of the laminae of the flexible mandrel or all are extracted at the same time, depending on severity of the contour.

  6. Polishing X-ray Mirror Mandrel

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA's Space Optics Manufacturing Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century - including the long-term goal of imaging Earth-like planets in distant solar systems. To reduce the cost of mirror fabrication, Marshall Space Flight Center (MSFC) has developed replication techniques, the machinery, and materials to replicate electro-formed nickel mirrors. The process allows fabricating precisely shaped mandrels to be used and reused as masters for replicating high-quality mirrors. MSFC's Space Optics Manufacturing Technology Center (SOMTC) has grinding and polishing equipment ranging from conventional spindles to custom-designed polishers. These capabilities allow us to grind precisely and polish a variety of optical devices, including x-ray mirror mandrels. This image shows Charlie Griffith polishing the half-meter mandrel at SOMTC.

  7. Polishing X-ray Mirror Mandrel

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA's Space Optics Manufacturing Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century - including the long-term goal of imaging Earth-like planets in distant solar systems. To reduce the cost of mirror fabrication, Marshall Space Flight Center (MSFC) has developed replication techniques, the machinery, and materials to replicate electro-formed nickel mirrors. The process allows fabricating precisely shaped mandrels to be used and reused as masters for replicating high-quality mirrors. MSFC's Space Optics Manufacturing Technology Center (SOMTC) has grinding and polishing equipment ranging from conventional spindles to custom-designed polishers. These capabilities allow us to grind precisely and polish a variety of optical devices, including x-ray mirror mandrels. This image shows Charlie Griffith polishing the half-meter mandrel at SOMTC.

  8. Mandrel development update

    SciTech Connect

    Buckley, S; Cook, B; Hassel, A; Takagi, M

    1999-02-01

    We report on the progress since January, 1998, in preparing polymer mandrels by microencapsulation for NIF scale ICF capsules that meet the required symmetry and surface finish requirements. During that time we successfully completed our FY98 DOE TDF4.1 milestone of improving the mandrel low mode to meet NIF requirements. A number of batches of 2 mm microencapsulated poly(a- methylstyrene) shells have been produced with mode 2 out-of-rounds of less than 2 {micro}m. Detailed characterization for these and other batches is presented. We have found that the key to reducing mode 2 out-of-round is the density matching of the composite oil/inner core water microencapsulated shell preform to the supporting bath. Density matching of the inner core water to the oil phase seems to be less important, perhaps because core centering is accomplished by other physical means. Shell roughness over the very important mode 10 to 100 region is still too high by at least a decade in power, and work aimed at improving this is the task for FY99. In addition to basic sphericity results we also report on a number of experiments designed to elucidate the fundamental scientific issues. In most cases the experiments reported are but starting points that will be followed up during FY99. Lastly we note that no effort has been placed on optimizing the overcoating and thermal decomposition steps, which must follow the successful microencapsulation step. Based upon GA's experience with smaller scale shells we are hopeful that these steps will not degrade capsule symmetry and surface finish. This question should be answered at least in part during FY99 as GA begins to supply finished 2 mm CH mandrels for the polyimide and Be ablator development work.

  9. Hydrodynamic Issues in PAMS Mandrel Target Fabrication

    SciTech Connect

    McQuillan, B M; Paguio, R; Subramanian, P; Takagi, M; Zebib, A

    2003-08-27

    Imperfections in PAMS mandrels critically govern the quality of final ICF targets. Imperfections in the mandrels can have a wide range of origins. Here, they present observations of 3 types of imperfections, and data to support the proposal that hydrodynamic factors during the curing of the mandrel are potential causes of these imperfections.

  10. HYDRODYNAMIC ISSUES IN PAMS MANDREL TARGET FABRICATION

    SciTech Connect

    McQUILLAN,B.W; PAGUIO,R; SUBRAMANIAN,P; TAKAGI,M; ZEBIB,A

    2003-09-01

    OAK-B135 Imperfections in PAMS mandrels critically govern the quality of final ICF targets. Imperfections in the mandrels can have a wide range of origins. Here, they present observations of 3 types of imperfections, and data to support the proposal that hydrodynamic factors during the curing of the mandrel are potential causes of these imperfections.

  11. Electro-Chemically Enhanced Mechanical Polishing of Nickel Mandrels

    NASA Technical Reports Server (NTRS)

    Gubarev, Mikhail; Ramsey, Brian; Engelhaupt, Darell

    2006-01-01

    Grinding and mechanical polishing techniques used for x-ray optics mandrel figuring lead to mid-frequency surface ripple. These small figure variations have to be addressed in order to improve the performance of the resulting x-ray mirrors. If the electrochemical etching is combined with mechanical polishing, the figuring and the surface finishing cm be done simultaneously and be used to correct the mid-frequency surface ripple. It is shown that the electrochemical mechanical polishing method allows selective removal of nickel alloy without mandrel surface microroughness degradation.

  12. Electro-Chemically Enhanced Mechanical Polishing of Nickel Mandrels

    NASA Technical Reports Server (NTRS)

    Gubarev, Mikhail; Ramsey, Brian; Engelhaupt, Darell

    2006-01-01

    Grinding and mechanical polishing techniques used for x-ray optics mandrel figuring lead to mid-frequency surface ripple. These small figure variations have to be addressed in order to improve the performance of the resulting x-ray mirrors. If the electrochemical etching is combined with mechanical polishing, the figuring and the surface finishing cm be done simultaneously and be used to correct the mid-frequency surface ripple. It is shown that the electrochemical mechanical polishing method allows selective removal of nickel alloy without mandrel surface microroughness degradation.

  13. Porous mandrels provide uniform deformation in hydrostatic powder metallurgy

    NASA Technical Reports Server (NTRS)

    Gripshover, P. J.; Hanes, H. D.

    1967-01-01

    Porous copper mandrels prevent uneven deformation of beryllium machining blanks. The beryllium powder is arranged around these mandrels and hot isostatically pressed to form the blanks. The mandrels are then removed by leaching.

  14. Recent Progress in NIF Mandrel Production

    SciTech Connect

    Takagi, M; Cook, R; McQuillan, B; Nikroo, A

    2003-09-03

    The production of spherical poly({alpha}-methylstyrene) (P{alpha}MS) mandrels utilizes a small amount (<0.1wt%) of high-molecular-weight poly(acrylic acid) (PAA) in the suspending medium, which substantially increases the interfacial tension during curing relative to methods using poly(vinyl alcohol) (PVA). However, fully cured capsules made by this method displayed a significant level of high frequency surface debris that became especially problematic when the mandrels were subsequently overcoated. To solve this problem we examined the use of PAA in conjunction with PVA in order to reduce these surface features, and explored numerous variations of concentration and timing of the PVA addition. The optimum conditions were found to be initial use of PAA for centering and symmetry of the mandrels, followed by removal of the PAA medium, washing of the mandrels with water, and finally transfer to PVA solution for completion of the curing cycle.

  15. Mandrels For Microtextured Small-Vessel Implants

    NASA Technical Reports Server (NTRS)

    Deininger, William D.; Gabriel, Stephen B.

    1989-01-01

    Research shows artificial blood-vessel and heart-valve implants made more compatible with their biological environments by use of regularly microtextured surfaces. In new manufacturing process, ion beam etches patterned array of small pillars on mandrel used to mold tubular plastic implant. Pillars create tiny regularly spaced holes in inner surface of tube. Holes expected to provide sites for attachment of healthy lining. Polytetrafluoroethylene (PTFE) used as mandrel material because it can be etched by ion beam.

  16. Mandrels For Microtextured Small-Vessel Implants

    NASA Technical Reports Server (NTRS)

    Deininger, William D.; Gabriel, Stephen B.

    1989-01-01

    Research shows artificial blood-vessel and heart-valve implants made more compatible with their biological environments by use of regularly microtextured surfaces. In new manufacturing process, ion beam etches patterned array of small pillars on mandrel used to mold tubular plastic implant. Pillars create tiny regularly spaced holes in inner surface of tube. Holes expected to provide sites for attachment of healthy lining. Polytetrafluoroethylene (PTFE) used as mandrel material because it can be etched by ion beam.

  17. Methodology for Producing Low Cost/Disposable Mandrels

    DTIC Science & Technology

    1979-12-01

    13 Materials Selection 13 Release Agents 14 Mandrel Materials 15 General 15 Cost Considerations 15 Fabrication Corts 16 Materials Properties ...Disposable Mandrel Material 67 3 List of Properties 68 1: 4 Specific Gravity/Density 69 5 Tensile Strength, kg/cmz (ksi) 71 2 5 6 Tensile Elastic Modulus...Material Costs 82 14 Absorption Test 83 15 Physical Properties of Candidate Mandrel Mateirlals 88 16 Evaluation of Mandrel Materials for DOA Propellant DTS

  18. Preparation of NIF Scale Poly ((alpha)-METHYLSTYRENE) Mandrels

    SciTech Connect

    Takagi, M; Cook, R; McQuillan, B; Elsner, F; Stephens, R; Nikroo, A; Paguio, S

    2002-06-07

    All planned National Ignition Facility (NIF) capsule targets except machined beryllium require a plastic mandrel upon which the ablator is applied. This mandrel must at least meet if not exceed the symmetry and surface finish requirements of the final capsule. The mandrels are produced by a two-step process. In the first step a thin-walled poly({alpha}-methylstyrene)(P{alpha}MS) shell is produced using microencapsulation techniques. This shell is overcoated with 10 to 15 {micro}m of glow discharge polymer (GDP) and then pyrolyzed at 300 C. This pyrolysis causes the P{alpha}MS to depolymerize to gas phase monomer that diffuses away through the more thermally stable plasma polymer shell, which retains all the symmetry of the original P{alpha}MS shell. Thus our challenge has been to produce 2-mm-diameter P{alpha}MS shells to serve as these initial ''decomposable'' mandrels that meet or exceed the current NIF design specifications. The basic microencapsulation process used in producing P{alpha}MS mandrels involves using a droplet generator to produce a water droplet (Wl) encapsulated by a fluorobenzene solution of P{alpha}MS (O), this compound droplet being suspended in a stirred aqueous bath (W2). Historically this bath has contained poly(vinyl alcohol) (PVA, 88% hydrolyzed, mol. wt. {approx}25,000 g/mol) to prevent agglomeration of the initially fluid compound droplets. As the compound droplets are stirred in the bath, the fluorobenzene solvent slowly dissipates leaving a solid P{alpha}MS shell. The internal water is subsequently removed by low temperature drying. We found using these techniques that 2-mm shells could easily be produced, however their low mode sphericity did not meet design specifications. In our last published report we detailed how replacement of the PVA with poly(acrylic acid) (PAA) resulted in a major improvement in sphericity due to a greatly increased interfacial tension between the bath and the compound droplet, relative to the use of PVA as

  19. A Flexible Alignment Fixture for the Fabrication of Replication Mandrels

    NASA Technical Reports Server (NTRS)

    Cuttino, James F.; Todd, Michael W.

    1996-01-01

    NASA uses precision diamond turning technology to fabricate replication mandrels for its X-ray Calibration Facility (XRCF) optics. The XRCF optics are tubular, and the internal surface contains a parabolic profile over the first section and a hyperbolic profile over the last. The optic is fabricated by depositing layers of gold and nickel on to the replication mandrel and then separating it from the mandrel. Since the mandrel serves as a replication form, it must contain the inverse image of the surface. The difficulty in aligning the mandrel comes from the fabrication steps which it undergoes. The mandrel is rough machined and heat treated prior to diamond turning. After diamond turning, silicon rubber separators which are undercut in radius by 3 mm (0.12 in.) are inserted between the two end caps of the mandrel to allow the plating to wrap around the ends (to prevent flaking). The mandrel is then plated with a nickel-phosphor alloy using an electroless nickel process. At this point, the separators are removed and the mandrel is reassembled for the final cut on the DTM. The mandrel is measured for profile and finish, and polished to achieve an acceptable surface finish. Wrapping the plating around the edges helps to prevent flaking, but it also destroys the alignment surfaces between the parts of the mandrel that insure that the axes of the parts are coincident. Several mandrels have been realigned by trial-and-error methods, consuming significant amounts of setup time. When the mandrel studied in this paper was reassembled, multiple efforts resulted in a minimum radial error motion of 100 microns. Since 50 microns of nickel plating was to be removed, and a minimum plating thickness of 25 microns was to remain on the part, the radial error motion had to be reduced to less than 25 microns. The mandrel was therefore not usable in its current state.

  20. A superconducting magnet mandrel with minimum symmetry laminations for proton therapy

    NASA Astrophysics Data System (ADS)

    Caspi, S.; Arbelaez, D.; Brouwer, L.; Dietderich, D. R.; Felice, H.; Hafalia, R.; Prestemon, S.; Robin, D.; Sun, C.; Wan, W.

    2013-08-01

    The size and weight of ion-beam cancer therapy gantries are frequently determined by a large aperture, curved, ninety degree, dipole magnet. The higher fields achievable with superconducting technology promise to greatly reduce the size and weight of this magnet and therefore also the gantry as a whole. This paper reports advances in the design of winding mandrels for curved, canted cosine-theta (CCT) magnets in the context of a preliminary magnet design for a proton gantry. The winding mandrel is integral to the CCT design and significantly affects the construction cost, stress management, winding feasibility, eddy current power losses, and field quality of the magnet. A laminated mandrel design using a minimum symmetry in the winding path is introduced and its feasibility demonstrated by a rapid prototype model. Piecewise construction of the mandrel using this laminated approach allows for increased manufacturing techniques and material choices. Sectioning the mandrel also reduces eddy currents produced during field changes accommodating the scan of beam energies during treatment. This symmetry concept can also greatly reduce the computational resources needed for 3D finite element calculations. It is shown that the small region of symmetry forming the laminations combined with periodic boundary conditions can model the entire magnet geometry disregarding the ends.

  1. Some aspects of the hydrodynamics of the microencapsulation route to NIF mandrels

    SciTech Connect

    Gresho, P M

    1998-10-20

    Spherical plastic shells for use as mandrels for the fabrication of ICF (Inertial Confinement Fusion) target capsules can be produced by solution-based microencapsulation techniques. The specifications for these mandrels in terms of sphericity are extremely rigorous, and it is clear that various aspects of the solution hydrodynamics associated with their production are important in controlling the quality of the final product. This paper explores what we know (and need to know) about the hydrodynamics of the microencapsulation process in order to lay the foundation for process improvements as well as identify inherent limits.

  2. Southern view of the aetna standard piercer and mandrel carriage ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Southern view of the aetna standard piercer and mandrel carriage with mandrel bits on left. No. 2 seamless line in bay 19 of the main pipe mill building. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  3. Removable Mandrels For Vacuum-Plasma-Spray Forming

    NASA Technical Reports Server (NTRS)

    Krotz, Phillip D.; Davis, William M.; Power, Christopher A.; Woodford, William H.; Todd, Douglas M.; Liaw, Yoon K.; Holmes, Richard R.; Zimmerman, Frank R.; Mckechnie, Timothy N.

    1995-01-01

    Improved mandrels developed for use in vacuum-plasma-spray (VPS) forming of refractory metal and ceramic furnace cartridge tubes. Designed so after tubes formed on them by VPS, mandrels shrink away from tubes upon cooling back to room temperature and simply slip out of tube.

  4. Forming Mandrels for X-Ray Mirror Substrates

    NASA Technical Reports Server (NTRS)

    Blake, Peter N.; Saha. To,p; Zhang, Will; O'Dell, Stephen; Kester, Thomas; Jones, William

    2011-01-01

    Precision forming mandrels are one element in X-ray mirror development at NASA. Current mandrel fabrication process is capable of meeting the allocated precision requirements for a 5 arcsec telescope. A manufacturing plan is outlined for a large IXO-scale program.

  5. Development of surface profiler for master mandrel of x-ray ellipsoidal mirror

    NASA Astrophysics Data System (ADS)

    Takei, Yoshinori; Mimura, Hidekazu

    2016-09-01

    The performance of ellipsoidal mirrors, which can be used to focus soft X-rays to nanometer spots, has not yet been optimized. Development of the surface profiler used in the fabrication process is a key step toward improving the performance of such mirrors. Because ellipsoidal mirrors have a complex geometry, our group has developed the following two-step process for their fabrication. First, a master mandrel with the inverse shape is prepared, after which the ellipsoidal mirror is fabricated by replicating the surface using an electroforming method. In this study, we develop a surface profiler for the master mandrel using multiple displacement sensors and motorized stages. One displacement sensor is used to measure the surface profile and the others are used to measure the motion errors of the stages. The longitudinal surface profiles of the mandrel could be measured with a repeatability of 1.58 nm (RMS). Based on the measured shape error profile, shape correction processing was conducted using elastic emission machining (EEM), which is an ultra-precision technique. After performing EEM three times, the shape error of the mandrel improved from 20.5 nm (RMS) to 4.2 nm (RMS).

  6. Challenges and mitigation strategies for resist trim etch in resist-mandrel based SAQP integration scheme

    NASA Astrophysics Data System (ADS)

    Mohanty, Nihar; Franke, Elliott; Liu, Eric; Raley, Angelique; Smith, Jeffrey; Farrell, Richard; Wang, Mingmei; Ito, Kiyohito; Das, Sanjana; Ko, Akiteru; Kumar, Kaushik; Ranjan, Alok; O'Meara, David; Nawa, Kenjiro; Scheer, Steven; DeVillers, Anton; Biolsi, Peter

    2015-03-01

    Patterning the desired narrow pitch at 10nm technology node and beyond, necessitates employment of either extreme ultra violet (EUV) lithography or multi-patterning solutions based on 193nm-immersion lithography. With enormous challenges being faced in getting EUV lithography ready for production, multi-patterning solutions that leverage the already installed base of 193nm-immersion-lithography are poised to become the industry norm for 10 and 7nm technology nodes. For patterning sub-40nm pitch line/space features, self-aligned quadruple patterning (SAQP) with resist pattern as the first mandrel shows significant cost as well as design benefit, as compared to EUV lithography or other multi-patterning techniques. One of the most critical steps in this patterning scheme is the resist mandrel definition step which involves trimming / reformation of resist profile via plasma etch for achieving appropriate pitch after the final pattern. Being the first mandrel, the requirements for the Line Edge Roughness (LER) / Line Width Roughness (LWR); critical dimension uniformity (CDU); and profile in 3-dimensions for the resist trim / reformation etch is extremely aggressive. In this paper we highlight the unique challenges associated in developing resist trim / reformation plasma etch process for SAQP integration scheme and summarize our efforts in optimizing the trim etch chemistries, process steps and plasma etch parameters for meeting the mandrel definition targets. Finally, we have shown successful patterning of 30nm pitch patterns via the resist-mandrel SAQP scheme and its implementation for Si-fin formation at 7nm node.

  7. Surface roughness evaluation on mandrels and mirror shells for future X-ray telescopes

    NASA Astrophysics Data System (ADS)

    Sironi, Giorgia; Spiga, D.

    2008-07-01

    More X-ray missions that will be operating in near future, like particular SIMBOL-X, e-Rosita, Con-X/HXT, SVOM/XIAO and Polar-X, will be based on focusing optics manufactured by means of the Ni electroforming replication technique. This production method has already been successfully exploited for SAX, XMM and Swift-XRT. Optical surfaces for X-ray reflection have to be as smooth as possible also at high spatial frequencies. Hence it will be crucial to take under control microroughness in order to reduce the scattering effects. A high rms microroughness would cause the degradation of the angular resolution and loss of effective area. Stringent requirements have therefore to be fixed for mirror shells surface roughness depending on the specific energy range investigated, and roughness evolution has to be carefully monitored during the subsequent steps of the mirror-shells realization. This means to study the roughness evolution in the chain mandrel, mirror shells, multilayer deposition and also the degradation of mandrel roughness following iterated replicas. Such a study allows inferring which phases of production are the major responsible of the roughness growth and could help to find solutions optimizing the involved processes. The exposed study is carried out in the context of the technological consolidation related to SIMBOL-X, along with a systematic metrological study of mandrels and mirror shells. To monitor the roughness increase following each replica, a multiinstrumental approach was adopted: microprofiles were analysed by means of their Power Spectral Density (PSD) in the spatial frequency range 1000-0.01 μm. This enables the direct comparison of roughness data taken with instruments characterized by different operative ranges of frequencies, and in particular optical interferometers and Atomic Force Microscopes. The performed analysis allowed us to set realistic specifications on the mandrel roughness to be achieved, and to suggest a limit for the

  8. Figuring Large Mandrels for Forming X-Ray Mirrors Substrates

    NASA Technical Reports Server (NTRS)

    Wright, Geraldine; Fleetwood, Charles; Content, David; Saha, Timo; Kolos, Linette; Colella, David

    2004-01-01

    Constellation X mirrors are discussed in this presentation. Topics include:assemblies, mirror segments, optical assemble pathfinder mandrels, the figuring process, and a best quadrant,clear aperture, and full aperture.

  9. Incoming Metrology of Segmented X-Ray Mandrels at MSFC

    NASA Technical Reports Server (NTRS)

    Gubarev, Mikhail; ODell, Steve; Kester, Thomas; Lehner, David; Jones, William; Smithers, Martin

    2004-01-01

    The Constellation-X Spectroscopy X-ray telescope (SXT) is designed to be built from X-ray optic segments. The X-ray segments will be fabricated from the segmented mandrels using a replication process. The purpose of the incoming metrology is to map the surface of the mandrels, so the performance of the X-ray optics produced can be predicted. Three Constellation-X segmented mandrels have been delivered to MSFC for incoming metrology. The segmented mandrels are 30-degree sections of a cylindrical surface and have diameters of 1.0 m, 1.2 m and 1.6 m. The maximum dimensions of the optical surface are 1.0 m axial length and 0.5 m azimuthal segment length. The metrology of the mandrels consists of the measurement of their slope differences, roundness, absolute radius, axial profile and microroughness. Accuracy goals for each type of measurement and the accuracy of the instruments used for the measurements will be discussed. The results of the mandrel metrology together with the performance predictions will be presented.

  10. Understanding the Critical Parameters of the PAMS Mandrel Fabrication Process

    SciTech Connect

    Bhandarkar, Suhas; Paguio, Reny; Elsner, Fred; Hoover, Denise

    2016-07-05

    As a part of an effort to continually better the roundness and roughness of ablator capsules, we looked at improving the same for the poly(alphamethylstyrene) or PAMS mandrels used to make the plastic capsules. The importance of this work is based on the fact that the surface properties of the mandrels set the lower limit for the ultimate attributes of the ablator capsule. These mandrels are made using an elegant double-emulsion process that uses the isotropic forces brought about by hydrostatic pressure and interfacial tension to seek sphericity. This paper describes the reasoning that led to investigating the so-called curing process where a solid PAMS shell is generated from a solution phase for achieving this goal. Using modeling to account for the mass transfer of the fluorobenzene solvent phase, we demonstrate that it is the control of the conditions through the percolation point of the system that leads to better mandrels. These concepts were implemented into the fabrication process to demonstrate significant improvements of the roundness of the mandrels.

  11. Understanding the Critical Parameters of the PAMS Mandrel Fabrication Process

    DOE PAGES

    Bhandarkar, Suhas; Paguio, Reny; Elsner, Fred; ...

    2016-07-05

    As a part of an effort to continually better the roundness and roughness of ablator capsules, we looked at improving the same for the poly(alphamethylstyrene) or PAMS mandrels used to make the plastic capsules. The importance of this work is based on the fact that the surface properties of the mandrels set the lower limit for the ultimate attributes of the ablator capsule. These mandrels are made using an elegant double-emulsion process that uses the isotropic forces brought about by hydrostatic pressure and interfacial tension to seek sphericity. This paper describes the reasoning that led to investigating the so-called curingmore » process where a solid PAMS shell is generated from a solution phase for achieving this goal. Using modeling to account for the mass transfer of the fluorobenzene solvent phase, we demonstrate that it is the control of the conditions through the percolation point of the system that leads to better mandrels. These concepts were implemented into the fabrication process to demonstrate significant improvements of the roundness of the mandrels.« less

  12. Understanding the Critical Parameters of the PAMS Mandrel Fabrication Process

    SciTech Connect

    Bhandarkar, Suhas; Paguio, Reny; Elsner, Fred; Hoover, Denise

    2016-07-05

    As a part of an effort to continually better the roundness and roughness of ablator capsules, we looked at improving the same for the poly(alphamethylstyrene) or PAMS mandrels used to make the plastic capsules. The importance of this work is based on the fact that the surface properties of the mandrels set the lower limit for the ultimate attributes of the ablator capsule. These mandrels are made using an elegant double-emulsion process that uses the isotropic forces brought about by hydrostatic pressure and interfacial tension to seek sphericity. This paper describes the reasoning that led to investigating the so-called curing process where a solid PAMS shell is generated from a solution phase for achieving this goal. Using modeling to account for the mass transfer of the fluorobenzene solvent phase, we demonstrate that it is the control of the conditions through the percolation point of the system that leads to better mandrels. These concepts were implemented into the fabrication process to demonstrate significant improvements of the roundness of the mandrels.

  13. Forming mandrels for making lightweight x-ray mirrors

    NASA Astrophysics Data System (ADS)

    Blake, Peter N.; Saha, Timo; Zhang, William W.; O'Dell, Stephen; Kester, Thomas; Jones, William

    2011-09-01

    Future x-ray astronomical missions, similar to the proposed International X-ray Observatory (IXO), will utilize replicated mirrors to reduce both mass and production costs. Accurately figured and measured molds (called mandrels) - on which the mirror substrates are thermally formed, replicating the surface of the mandrels - are essential to enable these missions. The Optics Branches of the Goddard Space Flight Center (GSFC) and Marshall Space Flight Center (MSFC) have developed fabrication processes along with metrologies that yield high-precision mandrels; and through the SBIR program, they encourage small businesses to attack parts of the remaining problems. The Goddard full-aperture mandrel polisher (the MPM-500) has been developed to a level where mandrel surfaces match the 1.5 arcsec HPD level allocation in a 5 arcsec telescope program. This paper reviews this current technology and describes a pilot program to design a suite of machine tools and process parameters capable of producing many hundreds of these precision objects. A major challenge is to keep mid-spatial frequency errors below 2 nm rms - a severe specification; but we must also note the factors which work to our advantage: e.g., how the figure departs from a pure cone by only one micron, and how the demanding figure specifications which apply in the axial direction are relaxed by an order of magnitude in the azimuthal. Careful study of other large optical fabrication programs in the light of these challenges and advantages has yielded a realistic plan for the economical production of mandrels that meet program requirements in both surface and quantity.

  14. Rotary roller mandrel of no. 2 seamless line in bays ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Rotary roller mandrel of no. 2 seamless line in bays 19 and 20 of the main pipe mill building looking south. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  15. Metathesis depolymerizable surfactants

    DOEpatents

    Jamison, Gregory M.; Wheeler, David R.; Loy, Douglas A.; Simmons, Blake A.; Long, Timothy M.; McElhanon, James R.; Rahimian, Kamyar; Staiger, Chad L.

    2008-04-15

    A class of surfactant molecules whose structure includes regularly spaced unsaturation in the tail group and thus, can be readily decomposed by ring-closing metathesis, and particularly by the action of a transition metal catalyst, to form small molecule products. These small molecules are designed to have increased volatility and/or enhanced solubility as compared to the original surfactant molecule and are thus easily removed by solvent extraction or vacuum extraction at low temperature. By producing easily removable decomposition products, the surfactant molecules become particularly desirable as template structures for preparing meso- and microstructural materials with tailored properties.

  16. A Stainless-Steel Mandrel for Slumping Glass X-ray Mirrors

    NASA Technical Reports Server (NTRS)

    Gubarev, Mikhail V.; O'Dell, Stephen L.; Jones, William D.; Kester, Thomas J.; Griffith, Charles W.; Zhang, William W.; Saha, Timo T.; Chan, Kai-Wing

    2009-01-01

    We have fabricated a precision full-cylinder stainless-steel mandrel at Marshall Space Flight Center. The mandrel is figured for a 30-cm diameter primary (paraboloid) mirror of an 840-cm focal-length Wolter-1 telescope. We have developed this mandrel for experiments in slumping.thermal forming at about 600 C.of glass mirror segments at Goddard Space Flight Center, in support of NASA's participation in the International X-ray Observatory (IXO). Precision turning of stainless-steel mandrels may offer a low-cost alternative to conventional figuring of fused-silica or other glassy forming mandrels. We report on the fabrication, metrology, and performance of this first mandrel; then we discuss plans and goals for stainless-steel mandrel technology.

  17. A Stainless-Steel Mandrel for Slumping Glass X-Ray Mirrors

    NASA Technical Reports Server (NTRS)

    ODell, Stephen L.; Gubarev, Mikhail V.; Jones, William D.; Kester, Thomas J.; Griffith, Charles W.; Zhang, William W.; Saha, Timo T.; Chan, Kai-Wing

    2008-01-01

    We have fabricated a precision full -cylinder stainless-steel mandrel at Marshall Space Flight Center. The mandrel is figured for a 30-cm-diameter primary (paraboloid) mirror of an 840-cm focal-lengthWolter-1 telescope. We have developed this mandrel for experiments in slumping.thermal forming at about 600 C-of glass mirror segments at Goddard Space Flight Center, in support of NASA fs participation in the International X -ray Observatory (IXO). Precision turning of stainless ]steel mandrels may offer a lowcost alternative to conventional figuring of fused -silica or other glassy forming mandrels. We report on the fabrication, metrology, and performance of this first mandrel; then we discuss plans and goals for stainless-steel mandrel technology.

  18. A Stainless-Steel Mandrel for Slumping Glass X-Ray Mirrors

    NASA Technical Reports Server (NTRS)

    ODell, Stephen L.; Gubarev, Mikhail V.; Jones, William D.; Kester, Thomas J.; Griffith, Charles W.; Zhang, William W.; Saha, Timo T.; Chan, Kai-Wing

    2008-01-01

    We have fabricated a precision full -cylinder stainless-steel mandrel at Marshall Space Flight Center. The mandrel is figured for a 30-cm-diameter primary (paraboloid) mirror of an 840-cm focal-lengthWolter-1 telescope. We have developed this mandrel for experiments in slumping.thermal forming at about 600 C-of glass mirror segments at Goddard Space Flight Center, in support of NASA fs participation in the International X -ray Observatory (IXO). Precision turning of stainless ]steel mandrels may offer a lowcost alternative to conventional figuring of fused -silica or other glassy forming mandrels. We report on the fabrication, metrology, and performance of this first mandrel; then we discuss plans and goals for stainless-steel mandrel technology.

  19. In Situ Metrology for the Corrective Polishing of Replicating Mandrels

    DTIC Science & Technology

    2010-06-08

    distribution is unlimited. 13. SUPPLEMENTARY NOTES Presented at Mirror Technology Days, Boulder, Colorado, USA, 7-9 June 2010. 14...ABSTRACT The International X-ray Observatory (IXO) will require mandrel metrology with extremely tight tolerances on mirrors with up to 1.6 meter radii...ideal. Error budgets for the IXO mirror segments are presented. A potential solution is presented that uses a voice-coil controlled gauging head, air

  20. Experimental Confirmation of CH Mandrel Removal from Be Shells

    SciTech Connect

    Cook, B; Letts, S; Buckley, S

    2004-06-09

    Sputtered Be shells are made by sputter deposition of Be, with a radially graded Cu dopant as necessary, onto plastic mandrels supplied by General Atomics. Although the plastic mandrel may not be a design issue, it is a fielding issue because at cryo temperatures the plastic shrinks more than the Be and delaminates. We described in previous memos a proposed method for thermally removing the plastic by burning it in air at elevated temperature. A key aspect to this process is getting air in and out of the shell through the small diameter hole that must be laser drilled in the capsule wall to serve as a fill hole for the fuel. Because the hole is quite small, gas flow through the orifice must be forced, and an external pressure variation was suggested to do this. Further calculations showed that since the volume of the capsule is quite small and the amount of plastic in the shell by comparison is large, the ''pumping'' of air in and out of the shell must occur at least once per minute in order to supply enough O{sub 2} to completely burn the plastic to CO{sub 2} and H{sub 2}O in a reasonable time. Such an apparatus has been now built and this memo details both its construction and operation, as well as provides the first evidence of plastic mandrel removal from Be shells.

  1. Filament to mandrel gap analysis: Resulting gap from filament winding over a cone-cylinder transition mandrel (reference NMTP NO. 93838)

    SciTech Connect

    Geraghty, P.

    1993-10-27

    The composites industry employs a method of high speed continuous reinforcement lay-down called filament winding. This is a process where resin impregnated tows, bundles of filament, are wound over a rotating mandrel. The tows, hereafter referred to as filament, are laid down over the rotating mandrel at a prescribed wind angle. Consider a cylindrical filament winding mandrel with conical features such that the filament is tangent to both the cylinder and the cone simultaneously. A gap is formed between the points of tangency. The gap distance measured along a line normal to the filament and intersecting the mandrel`s axis of rotation. The maximum distance occurs between the filament and a point on the intersection of the cylinder and the cone. The problems this paper addresses are: given a cylindrical filament winding mandrel with conical features, what is the gap size for a given wind angle; conversely what is the wind angle for a given gap size; and what does the geometry need to be in the mandrel transition area between the cylinder cone such that the filament remains in contact with the mandrel at all times?

  2. Inflatable mandrel fabrication technology - Advantages for the containment of rocket propellants

    NASA Astrophysics Data System (ADS)

    Moser, Daniel J.

    1992-07-01

    This paper discusses and compares the attributes of various mandrel types as they pertain to the fabrication of filament-wound composite containment vessels for rocket propellants, solid or liquid. The issues of dimensional conformity, processing parameters, unit costs, vessel performance, and development lead times are raised. The continuous fiber reinforced, reusable inflatable mandrel concept is explained and shown to have unique advantages over more traditional mandrel types. Burst pressure performance is equivalent to, or slightly better than, the results from vessels built on the more conventional net metal mandrel. The co-cured insulator process used in conjunction with the inflatable mandrel is shown to be superior in some respects. Some experimental findings are presented along with description of the processing parameters that must be understood when using inflatable mandrels.

  3. Braiding Simulation and Slip Evaluation for Arbitrary Mandrels

    NASA Astrophysics Data System (ADS)

    Akkerman, Remko; Villa Rodríguez, Blasimir Hadir

    2007-04-01

    Braiding is a manufacturing process that is increasingly being used to manufacture pre-forms for Resin Transfer Moulding. A fast simulation method is presented for the prediction of the fibre distribution on complex braided parts and complex kinetic situations (e.g. changes in velocity, orientation). The implementation is suited for triangular surface representations as generated by many CAD software packages in use. Experimental results show that the results are sensitive to the friction conditions in particular regions. The friction conditions between the yarns and the mandrel are analysed, leading to the development of a slip indicator.

  4. System for maintaining the alignment of mandrels in filament winding operations

    DOEpatents

    Robinson, Samuel C.; Dodge, William G.; Pollard, Roy E.

    1984-01-01

    The present invention is directed to a system for sensing and correcting the alignment of a mandrel being wound with filamentary material with respect to the filamentary material winding mechanism. A positioned reference pin attached to the mandrel is positioned in a beam of collimated light emanating from a laser so as to bisect the light beam and create a shadow therebetween. A pair of photocells are positioned to receive the bisected light beam with the shadow uniformly located between the photocells when the pin is in a selected position. The mandrel is supported in the selected position for the winding of a filamentary material by a position adjustable roller mechanism which is coupled by a screw drive to a reversible motor. Changes in the pin position such as caused by winding growth are sensed by the photocells to provide the displacement of the roller mechanism in the direction necessary to return the mandrel to the selected position.

  5. Superpolishing and Precision Metrology on a Metal Mandrel and Replicated Segments for Constellation-X

    NASA Technical Reports Server (NTRS)

    Content, D.; Lyons, J.; Saha, T.; Wright, G.; Zaniewski, J.; Petre, R.; Chan, K. W.

    1999-01-01

    We have superpolished a diamond-turned aluminum mandrel (coated with electroless Ni) to an axial roughness of 0.34 nm rms. The mandrel is made to the Astro-E secondary mirror design for the 81st shell. Precision metrology at 100 mm to submicron scales has established the power spectral density of the mandrel and ultralightweight gold coated replicated segments. Predicted image quality of a set of optimally aligned replicated segments of this and a matching primary is substantially improved as compared to the flight mirrors for Astro-E. This approach using metal mandrels, superpolishing, and replicated ultralightweight foil mirrors, may represent a cost-effective approach to meeting the 15 arcsec half-energy width and weight requirements for the Constellation-X mission. Descriptions of the polishing apparatus, the precision metrology instruments, and the surface data analysis are presented. The general methods described are applicable to precision optics for both normal incidence and grazing incidence optics.

  6. Superpolishing and Precision Metrology on a Metal Mandrel and Replicated Segments for Constellation-X

    NASA Technical Reports Server (NTRS)

    Content, D.; Saha, T.; Petre, R.; Lyons, J. J., III; Wright, G.; Zaniewski, J.; Chan, K. W.

    1999-01-01

    We have superpolished a diamond-turned aluminum mandrel (coated with electroless Ni) to an axial roughness of 6.34 nm rms. The mandrel is made to the Astro-E secondary mirror design for the 81st shell. Precision metrology at 100 mm to submicron scales has established the power spectral density of the mandrel and ultralightweight gold coated replicated segments. Predicted image quality of a set of optimally aligned replicated segments of this and a matching primary is substantially improved as compared to the flight mirrors for Astro-E. This approach using metal mandrels, superpolishing, and replicated ultralightweight foil mirrors, may represent a cost-effective approach to meeting the 15 arcsec half-energy width and weight requirements for the Constellation-X mission. Descriptions of the polishing apparatus, the precision metrology instruments, and the surface data analysis are presented. The general methods described are applicable to precision optics for both normal incidence and grazing incidence optics.

  7. System for maintaining the alignment of mandrels in filament winding operations

    DOEpatents

    Robinson, S.C.; Dodge, W.G.; Pollard, R.E.

    1983-10-12

    The present invention is directed to a system for sensing and correcting the alignment of a mandrel being wound with filamentary material with respect to the filamentary material winding mechanism. A positioned reference pin attached to the mandrel is positioned in a beam of collimated light emanating from a laser so as to bisect the light beam and create a shadow therebetween. A pair of photocells are positioned to receive the bisected light beam with the shadow uniformly located between the photocells when the pin is in a selected position. The mandrel is supported in the selected position for the winding of a filamentary material by a position adjustable roller mechanism which is coupled by a screw drive to a reversible motor. Changes in the pin position such as caused by winding growth are sensed by the photocells to provide the displacement of the roller mechanism in the direction necessary to return the mandrel to the selected position.

  8. Computer-Controlled Cylindrical Polishing Process for Large X-Ray Mirror Mandrels

    NASA Technical Reports Server (NTRS)

    Khan, Gufran S.; Gubarev, Mikhail; Speegle, Chet; Ramsey, Brian

    2010-01-01

    We are developing high-energy grazing incidence shell optics for hard-x-ray telescopes. The resolution of a mirror shells depends on the quality of cylindrical mandrel from which they are being replicated. Mid-spatial-frequency axial figure error is a dominant contributor in the error budget of the mandrel. This paper presents our efforts to develop a deterministic cylindrical polishing process in order to keep the mid-spatial-frequency axial figure errors to a minimum. Simulation software is developed to model the residual surface figure errors of a mandrel due to the polishing process parameters and the tools used, as well as to compute the optical performance of the optics. The study carried out using the developed software was focused on establishing a relationship between the polishing process parameters and the mid-spatial-frequency error generation. The process parameters modeled are the speeds of the lap and the mandrel, the tool s influence function, the contour path (dwell) of the tools, their shape and the distribution of the tools on the polishing lap. Using the inputs from the mathematical model, a mandrel having conical approximated Wolter-1 geometry, has been polished on a newly developed computer-controlled cylindrical polishing machine. The preliminary results of a series of polishing experiments demonstrate a qualitative agreement with the developed model. We report our first experimental results and discuss plans for further improvements in the polishing process. The ability to simulate the polishing process is critical to optimize the polishing process, improve the mandrel quality and significantly reduce the cost of mandrel production

  9. Evaluation of left ventricular assist device pump bladders cast from ion-sputtered polytetrafluorethylene mandrels

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A highly thromboresistant blood contacting interface for use in implanatable blood pump is investigated. Biomaterials mechanics, dynamics, durability, surface morphology, and chemistry are among the critical consideration pertinent to the choice of an appropriate blood pump bladder material. The use of transfer cast biopolymers from ion beam textured surfaces is investigated to detect subtle variations in blood pump surface morphology using Biomer as the biomaterial of choice. The efficacy of ion beam sputtering as an acceptable method of fabricating textured blood interfaces is evaluated. Aortic grafts and left ventricular assist devices were implanted in claves; the blood interfaces were fabricated by transfer casting methods from ion beam textured polytetrafluorethylene mandrels. The mandrels were textured by superimposing a 15 micron screen mesh; ion sputtering conditions were 300 volts beam energy, 40 to 50 mA beam, and a mandrel to source distance of 25 microns.

  10. New approaches to the preparation of P(alpha)MS beads as mandrels for NIF-scale target capsules

    SciTech Connect

    Buckley, S R; Cook, R C; Fearon, E; Letts, S A

    1998-10-20

    We report on a new method using heated density gradient columns for preparing spherical poly({alpha} - methylstyrene) (P{alpha}MS) bead mandrels for inertial confinement fusion spherical shell targets. Using 1,2 propane diol/glycerol mixtures, stable density gradient columns for supporting P{alpha}MS beads can be prepared at temperatures as high as 150 {degrees}C. At these temperatures plasticized commercial beads become fluid and spherical, however loss of the plasticizer and very low molecular weight components of the bead due to limited solubility in the column fluid leads to surface finish problems. We also present results on P{alpha}MS beads prepared in an aqueous bath batch mode. Using these techniques beads with maximum out-of-rounds less than 5 {micro}m have been produced.

  11. Hydraulic fluid serves as mandrel for small diameter refractory tube drawing

    NASA Technical Reports Server (NTRS)

    Mayfield, R. M.

    1966-01-01

    Sealing hydraulic fluid within a tube and passing the tube through a reducing die produces high quality small diameter refractory metal tubing. The encased fluid eliminates the need for mandrel or ductile core removal and drawing can proceed with less handling operations.

  12. Model for the thermal state of the mandrel in an electroslag furnace

    NASA Astrophysics Data System (ADS)

    Yachikov, I. M.; Vdovin, K. N.; Tochilkin, V. V.

    2016-06-01

    The design of the mold in an electroslag furnace for melting hollow billets for metal-cutting knives, which has a water-cooling mandrel, is considered. A scheme for cooling of the copper mandrel is proposed. A mathematical model is developed, and an algorithm is proposed to calculate the thermal state of the mandrel at the chosen geometric parameters, a given number of water-cooling channels, and certain cooling water parameters. It is found for an internal copper mold 200 mm in diameter that a stationary thermal regime is reached in at most 5 min. An increase in the number of channels at the same total cross-sectional area is shown to cause a decrease in the temperature gradients and the maximum temperature in the internal mold. The ANSYS software package is used to simulate the thermal state of the copper mandrel of the proposed design at given water cooling parameters. The calculations support the adequacy of the proposed mathematical model.

  13. Air backed mandrel type fiber optic hydrophone with low noise floor

    NASA Astrophysics Data System (ADS)

    Rajesh, R.; V, Sreehari C.; N, Praveen Kumar; Awasthi, R. L.; K, Vivek; B, Vishnu M.; Santhanakrishnan, T.; Moosad, K. P. B.; Mathew, Basil

    2014-10-01

    Low noise fiber optic hydrophone based on optical fiber coil wound on air-backed mandrel was developed. The sensor can be effectively used for underwater acoustic sensing. The design and characterization of the hydrophone is illustrated in this paper. A fiber Mach-Zehnder Interferometer (MZI) was developed and coupled with a Distributed Feedback (DFB) fiber laser source and an optical phase demodulation system, with an active modulation in one of the arms. The sensor head design was optimized to achieve noise spectral density <10 μrad/√Hz, for yielding sufficient sensitivity to sense acoustic pressure close to Deep Sea Sate Zero (DSS0).

  14. The effect of mandrel material on the processing-induced residual stresses in thick filament wound composite cylinders

    NASA Astrophysics Data System (ADS)

    White, S. R.; Zhang, Z.

    1993-06-01

    Residual stresses are known to be detrimental to a number of mechanical properties in composite materials. The mechanisms by which they develop in the filament winding of composite cylinders and tubes is not fully understood. In this work a process model is presented to predict the residual stresses induced during the processing of two-layer composite cylinders. Chemical shrinkage, thermal expansion/contraction, and cure-dependent mechanical properties are accounted for in the model. The influence of mandrel stiffness and thermal expansion coefficient is examined and a case study of an aluminum and a steel mandrel is compared. The residual stress field is shown to be strongly affected by the mandrel thermal expansion coefficient.

  15. Electromagnetic levitation coil fabrication technique for MSFC containerless processing facilities

    NASA Technical Reports Server (NTRS)

    Ethridge, E. C.; Theiss, J.; Curreri, P. A.; Abbaschian, G. J.

    1983-01-01

    A technique is described for more reproducible fabrication of electromagnetic levitation coils. A split mandrel was developed upon which the coil is wound. After fabrication the mandrel can be disassembled to remove it from the coil. Previously, a full day was required to fabricate a levitation coil and the success rate for a functional coil was only 50 percent. About eight coils may be completed in one day using the technique developed and 95 percent of them are good levitation coils.

  16. Piercing mandrel strengthening by surfacing with nickel aluminide-based alloy

    NASA Astrophysics Data System (ADS)

    Zorin, I. V.; Dubtsov, Yu N.; Sokolov, G. N.; Artem'ev, A. A.; Lysak, V. I.; Elsukov, S. N.

    2017-02-01

    Electrode composite wire (CW) was used for argon-arc surfacing of a thermal-resisting nickel aluminide-based alloy (Ni-Al-Cr-W-Mo-Ta system) on the butt-end surface of the non-water-cooled piercing mandrel. It was shown that multipassing surfacing forms a defect-free deposited metal based on the γ’-Ni3Al phase of various structural origins. Using high-temperature sclerometry and thermal fatigue testing methods, the metal deposited with CW containing ultrafine particle of 0.3–0.4 % wt. WC carbide features increased resistance to thermal and force effects at temperatures up to 1200 °C.

  17. Multi-Stress Monitoring System with Fiber-Optic Mandrels and Fiber Bragg Grating Sensors in a Sagnac Loop

    PubMed Central

    Kim, Hyunjin; Sampath, Umesh; Song, Minho

    2015-01-01

    Fiber Bragg grating sensors are placed in a fiber-optic Sagnac loop to combine the grating temperature sensors and the fiber-optic mandrel acoustic emission sensors in single optical circuit. A wavelength-scanning fiber-optic laser is used as a common light source for both sensors. A fiber-optic attenuator is placed at a specific position in the Sagnac loop in order to separate buried Bragg wavelengths from the Sagnac interferometer output. The Bragg wavelength shifts are measured with scanning band-pass filter demodulation and the mandrel output is analyzed by applying a fast Fourier transform to the interference signal. This hybrid-scheme could greatly reduce the size and the complexity of optical circuitry and signal processing unit, making it suitable for low cost multi-stress monitoring of large scale power systems. PMID:26230700

  18. Multi-Stress Monitoring System with Fiber-Optic Mandrels and Fiber Bragg Grating Sensors in a Sagnac Loop.

    PubMed

    Kim, Hyunjin; Sampath, Umesh; Song, Minho

    2015-07-29

    Fiber Bragg grating sensors are placed in a fiber-optic Sagnac loop to combine the grating temperature sensors and the fiber-optic mandrel acoustic emission sensors in single optical circuit. A wavelength-scanning fiber-optic laser is used as a common light source for both sensors. A fiber-optic attenuator is placed at a specific position in the Sagnac loop in order to separate buried Bragg wavelengths from the Sagnac interferometer output. The Bragg wavelength shifts are measured with scanning band-pass filter demodulation and the mandrel output is analyzed by applying a fast Fourier transform to the interference signal. This hybrid-scheme could greatly reduce the size and the complexity of optical circuitry and signal processing unit, making it suitable for low cost multi-stress monitoring of large scale power systems.

  19. Study on the DFB fiber laser accelerometer with a metal-shell-packaged single-cylinder mandrel structure

    NASA Astrophysics Data System (ADS)

    Li, Haitao; Ma, Lina; Yang, Huayong; Luo, Hong

    2014-12-01

    To realize the miniature of fiber laser accelerometers, a metal-shell-packaged single-cylinder mandrel-structured distributed feedback (DFB) fiber laser accelerometer was proposed, whose key sensing component is the DFB fiber laser with a cavity length of 16mm. Simulation results show that when the weight of the mass is 400g, the radius of the thin shell cylinder is 0.5cm, we will find that the resonance frequency of the sensor is 900Hz and its sensitivity reaches 18.1pm/g. It is also shown that its sensitivity achieved 42.8dB.re.rad/g while demodulated by an unbalanced Michelson optical fiber interferometer with 1m path difference. In addition, the effects of its structure and material parameters on the acceleration sensitivity are also studied.

  20. PREPARATION OF CU-DOPED GLOW DISCHARGE POLYMER COATINGS FOR ICF APPLICATIONS

    SciTech Connect

    NIKROO,A; CASTILLO,E; HILL,D.W; GREENWOOD,A.L.

    2003-06-01

    OAK-B135 Copper doped polymer shells can provide a very useful diagnostic for fast ignition experiments currently being performed at various laboratories around the world. The low concentration copper dopant acts as an efficient x-ray source providing information on the physics of fast ignition. They have developed copper doped glow discharge (GDP) coatings suitable for such purposes. Copper acetylacetonate (CuAcAC), a solid at room temperature, was used in a heated jacket as the dopant source. They used this technique to fabricate thin ({approx} 5-7 {micro}m) GDP shells doped with {approx} 1 at% copper through the depolymerizable mandrel process for fast ignition experiments. The details of the experimental set up and the range and limitations of the technique are discussed.

  1. Advanced Materials and Fabrication Techniques for the Orion Attitude Control Motor

    NASA Technical Reports Server (NTRS)

    Gorti, Sridhar; Holmes, Richard; O'Dell, John; McKechnie, Timothy; Shchetkovskiy, Anatoliy

    2013-01-01

    Rhenium, with its high melting temperature, excellent elevated temperature properties, and lack of a ductile-to-brittle transition temperature (DBTT), is ideally suited for the hot gas components of the ACM (Attitude Control Motor), and other high-temperature applications. However, the high cost of rhenium makes fabricating these components using conventional fabrication techniques prohibitive. Therefore, near-net-shape forming techniques were investigated for producing cost-effective rhenium and rhenium alloy components for the ACM and other propulsion applications. During this investigation, electrochemical forming (EL-Form ) techniques were evaluated for producing the hot gas components. The investigation focused on demonstrating that EL-Form processing techniques could be used to produce the ACM flow distributor. Once the EL-Form processing techniques were established, a representative rhenium flow distributor was fabricated, and samples were harvested for material properties testing at both room and elevated temperatures. As a lower cost and lighter weight alternative to an all-rhenium component, rhenium- coated graphite and carbon-carbon were also evaluated. The rhenium-coated components were thermal-cycle tested to verify that they could withstand the expected thermal loads during service. High-temperature electroforming is based on electrochemical deposition of compact layers of metals onto a mandrel of the desired shape. Mandrels used for electro-deposition of near-net shaped parts are generally fabricated from high-density graphite. The graphite mandrel is easily machined and does not react with the molten electrolyte. For near-net shape components, the inner surface of the electroformed part replicates the polished graphite mandrel. During processing, the mandrel itself becomes the cathode, and scrap or refined refractory metal is the anode. Refractory metal atoms from the anode material are ionized in the molten electrolytic solution, and are deposited

  2. Thrust chamber thermal barrier coating techniques

    NASA Technical Reports Server (NTRS)

    Quentmeyer, Richard J.

    1988-01-01

    Methods for applying thermal barrier coatings to the hot-gas side wall of rocket thrust chambers in order to significantly reduce the heat transfer in high heat flux regions was the focus of technology efforts for many years. This paper describes a successful technique developed by the Lewis Research Center that starts with the coating of a mandrel and then builds the thrust chamber around it by electroforming appropriate materials. This results in a smooth coating with exceptional adherence, demonstrated in hot fire rig tests. The low cycle fatigue life of chambers with coatings applied in this manner was increased dramatically compared to uncoated chambers.

  3. Thrust chamber thermal barrier coating techniques

    NASA Technical Reports Server (NTRS)

    Quentmeyer, Richard J.

    1989-01-01

    Methods for applying thermal barrier coatings to the hot-gas side wall of rocket thrust chambers in order to significantly reduce the heat transfer in high heat flux regions has been the focus of technology efforts for many years. A successful technique developed by NASA-Lewis that starts with the coating on a mandrel and then builds the thrust chamber around it by electroforming appropriate materials is described. This results in a smooth coating with exceptional adherence, as was demonstrated in hot fire rig tests. The low cycle fatigue life of chambers with coatings applied in this manner was increased dramatically compared to uncoated chambers.

  4. Technique for the efficient and reproducible fabrication of electromagnetic levitation coils

    NASA Technical Reports Server (NTRS)

    Ethridge, E. C.; Curreri, P. A.; Theiss, J.; Abbaschian, G. J.

    1984-01-01

    A technique has been developed for fabricating electromagnetic induction coils in a reproducible manner. The process utilizes a split mandrel that can be disassembled to remove the mandrel from the coil. The technique has increased coil production rates by a factor of 8 over the freehand winding method. The success rate for producing a functional levitation coil has been increased from 50 percent to 95 percent. The levitation coil designed during this work has successfully levitated and melted a variety of alloys including Cu, Ag, Ag-Ni, Cu-Fe, Fe-C, and Nb-Ge. W was also levitated but not melted at temperatures as high as 2700 C. The highest sample melt temperature achieved was 2400 C for the Nb-Ge samples.

  5. Continuous polymer nanofibers by extrusion into a viscous medium: A modified wet-spinning technique

    NASA Astrophysics Data System (ADS)

    Gorantla, M.; Boone, S. E.; El-Ashry, M.; Young, D.

    2006-02-01

    We present a wet-spinning technique capable of producing continuous polymer nanofibers. This method involves injecting a solvated polymer into a highly viscous moving medium through a microaperture. The extruded fiber moves in a predictable spiral path and is collected around a spinning mandrel which also serves to pull the extruded fiber away from the aperture. Semicontinuous, solid nanofibers of polyvinyl butyral were produced with diameters ranging from 10μmto400nm. Electron microscopy indicates that submicron fibers exhibit a ribbonlike morphology. The effect of different processing parameters on the fiber size and shape is discussed.

  6. FABRICATION AND CHARACTERIZATION OF FAST IGNITION TARGETS

    SciTech Connect

    HILL,D.W; CASTILLO,E; CHEN,K.C; GRANT,S.E; GREENWOOD,A.L; KAAE,J.L; NIKROO,A; PAGUIO,S.P; SHEARER,C; SMITH,JR.,J.N; STEPHENS,R.B; STEINMAN,D.A; WALL,J

    2003-06-01

    OAK-B135 Fast ignition is a novel scheme for achieving laser fusion. A class of these targets involves cone mounted CH shells. The authors have been fabricating such targets with shells with a wide variety of diameters and wall thicknesses for several years at General Atomics. In addition, recently such shells were needed for implosion experiments at Laboratory for Laser Energetics (LLE) that for the first time were required to be gas retentive. Fabrication of these targets requires producing appropriate cones and shells, assembling the targets, and characterization of the assembled targets. The cones are produced using micromachining and plating techniques. The shells are fabricated using the depolymerizable mandrel technique followed by micromachining a hole for the cone. The cone and the shell then need to be assembled properly for gas retention and precisely in order to position the cone tip at the desired position within the shell. Both are critical for the fast ignition experiments. The presence of the cone in the shell creates new challenges in characterization of the assembled targets. Finally, for targets requiring a gas fill, the cone-shell assembly needs to be tested for gas retention and proper strength at the glue joint. This paper presents an overview of the developmental efforts and technical issues addressed during the fabrication of fast ignition targets.

  7. Fabrication and Characterization of Fast Ignition Targets

    SciTech Connect

    Hill, D.W.; Castillo, E.; Chen, K.C.; Grant, S.E.; Greenwood, A.L.; Kaae, J.L.; Nikroo, A.; Paguio, S.P.; Shearer, C.; Smith, J.N. Jr.; Stephens, R.B.; Steinman, D.A.; Wall, J.

    2004-03-15

    Fast ignition is a novel scheme for achieving laser fusion. A class of these targets involves cone mounted CH shells. We have been fabricating such targets with shells with a wide variety of diameters and wall thicknesses for several years at General Atomics. In addition, recently such shells were needed for implosion experiments at Laboratory for Laser Energetics (LLE) that for the first time were required to be gas retentive. Fabrication of these targets requires producing appropriate cones and shells, assembling the targets, and characterization of the assembled targets. The cones are produced using micromachining and plating techniques. The shells are fabricated using the depolymerizable mandrel technique followed by micromachining a hole for the cone. The cone and the shell then need to be assembled properly for gas retention and precisely in order to position the cone tip at the desired position within the shell. Both are critical for the fast ignition experiments. The presence of the cone in the shell creates new challenges in characterization of the assembled targets. Finally, for targets requiring a gas fill, the cone-shell assembly needs to be tested for gas retention and proper strength at the glue joint. This paper presents an overview of the developmental efforts and technical issues addressed during the fabrication of fast ignition targets.

  8. Comparison of fabrication techniques for hollow retroreflectors

    NASA Astrophysics Data System (ADS)

    Preston, Alix; Merkowitz, Stephen

    2014-06-01

    Despite the wide usage of hollow retroreflectors, there is limited literature involving their fabrication techniques and only two documented construction methods could be found. One consists of an adjustable fixture that allows for the independent alignment of each mirror, while the other consists of a modified solid retroreflector that is used as a mandrel. Although both methods were shown to produce hollow retroreflectors with arc second dihedral angle errors, a comparison and analysis of each method could not be found, which makes it difficult to ascertain which method would be better suited to use for precision-aligned retroreflectors. Although epoxy bonding is generally the preferred method to adhere the three mirrors, a relatively new method known as hydroxide-catalysis bonding (HCB) presents several potential advantages over epoxy bonding. HCB has been used to bond several optical components for space-based missions, but has never been applied for construction of hollow retroreflectors. We examine the benefits and limitations of each bonding fixture as well as the present results and analysis of hollow retroreflectors made using both epoxy and HCB techniques.

  9. New technique for installing screen wicking into Inconel 718 heat pipe

    NASA Astrophysics Data System (ADS)

    Giriunas, Julius A.; Watson, Gordon K.; Tower, Leonard K.

    1993-01-01

    The creep behavior of superalloys, including Inconel 718, in the presence of liquid sodium is not yet known. To study this problem, the NASA Lewis Research Center has initiated a program with the Energy Technology Engineering Center (ETEC) of Rockwell International Corporation to fill with sodium and creep-test three small cylindrical heat pipes of Inconel 718 for a period of 1000 hours each. This report documents the design and the construction methods that were used at NASA Lewis to fabricate these heat pipes. Of particular importance in the heat pipe construction was the installation of the screen wicking by using an expandable mandrel and differential thermal expansion. This installation technique differs from anything known to have been reported in the heat pipe literature and may be of interest to other workers in the heat pipe field.

  10. New technique for installing screen wicking into Inconel 718 heat pipe

    SciTech Connect

    Giriunas, J.A.; Watson, G.K. ); Tower, L.K. )

    1993-01-10

    The creep behavior of superalloys, including Inconel 718, in the presence of liquid sodium is not yet known. To study this problem, the NASA Lewis Research Center has initiated a program with the Energy Technology Engineering Center (ETEC) of Rockwell International Corporation to fill with sodium and creep-test three small cylindrical heat pipes of Inconel 718 for a period of 1000 hours each. This report documents the design and the construction methods that were used at NASA Lewis to fabricate these heat pipes. Of particular importance in the heat pipe construction was the installation of the screen wicking by using an expandable mandrel and differential thermal expansion. This installation technique differs from anything known to have been reported in the heat pipe literature and may be of interest to other workers in the heat pipe field.

  11. Depolymerizable Poly(O-vinyl carbamate-alt-sulfones) as Customizable Macromolecular Scaffolds for Mucosal Drug Delivery.

    PubMed

    Kumar, Kaushlendra; Castaño, Eduard Jimenez; Weidner, Andrew R; Yildirim, Adem; Goodwin, Andrew P

    2016-05-17

    Interest in stimulus responsive materials and polymers has grown over the years, having shown great promise in a diverse set of applications. For drug delivery, stimulus-responsive polymers have been shown to encapsulate therapeutic cargo such as small molecule drugs or proteins, deliver them to specific locations in the body, and release them so that they can induce a therapeutic effect in the patient. Most hydrolytically degradable polymers are synthesized via nucleophilic, anionic, or cationic polymerization, which generally requires protection of nucleophilic or protic side chains prior to polymerization. Here, we report the synthesis of novel, alternating copolymers of sulfur dioxide and O-vinyl carbamate monomers that boast excellent functional group tolerance and pH-dependent instability. Alternating copolymers were synthesized containing pendant functionalities such as alcohol, carboxylic acid, ester, and azide without deprotection or post-polymerization modification. The copolymers were then formulated via nanoprecipitation into polymer nanoparticles capable of encapsulating small molecule dyes. The polymer nanoparticles were found to degrade rapidly at pH > 6 and were stable even in highly acidic conditions. Based on this observation, a proof-of-concept study for mucosal delivery was performed in polymer nanoparticles entrapped in a mucus model. At pH 8 the diffusion of encapsulated dye was found to be similar to free dye, while at pH 5 the diffusion coefficient was an order of magnitude lower. Cell viability was retained at 200 µg/mL particles after 24 h incubation. These polymers thus show promise as highly customizable scaffolds for mucosal drug delivery.

  12. A Comparison of Fabrication Techniques for Hollow Retroreflectors

    NASA Technical Reports Server (NTRS)

    Preston, Alix; Merkowitz, Stephen

    2014-01-01

    Despite the wide usage of hollow retroreflectors, there is limited literature involving their fabrication techniques and only two documented construction methods could be found. One consists of an adjustable fixture that allows for the independent alignment of each mirror, while the other consists of a modified solid retroreflector that is used as a mandrel. Although both methods were shown to produce hollow retroreflectors with arcsecond dihedral angle errors, a comparison and analysis of each method could not be found which makes it difficult to ascertain which method would be better suited to use for precision-aligned retroreflectors. Although epoxy bonding is generally the preferred method to adhere the three mirrors, a relatively new method known as hydroxide-catalysis bonding (HCB) presents several potential advantages over epoxy bonding. HCB has been used to bond several optical components for space-based missions, but has never been applied for construction of hollow retroreflectors. In this paper we examine the benefits and limitations of each bonding fixture as well as present results and analysis of hollow retroreflectors made using both epoxy and HCB techniques.

  13. Differential deposition technique for figure corrections in grazing-incidence x-ray optics

    NASA Astrophysics Data System (ADS)

    Kilaru, Kiranmayee; Ramsey, Brian D.; Gubarev, Mikhail V.; Gregory, Don A.

    2011-10-01

    A differential deposition technique was investigated as a way to minimize axial figure errors in full-shell, grazing-incidence, reflective x-ray optics. These types of optics use a combination of off-axis conic segments--hyperbolic, parabolic, and/or elliptical, to reflect and image x-rays. Several such mirrors or ``shells'' of decreasing diameter are typically concentrically nested to form a single focusing unit. Individual mirrors are currently produced at Marshall Space Flight Center using an electroforming technique, in which the shells are replicated off figured and superpolished mandrels. Several factors in this fabrication process lead to low- and mid-spatial frequency deviations in the surface profile of the shell that degrade the imaging quality of the optics. A differential deposition technique, discussed in this paper, seeks to improve the achievable resolution of the optics by correcting the surface profile deviations of the shells after fabrication. As a proof of concept, the technique was implemented on small-animal radionuclide-imaging x-ray optics being considered for medical applications. This paper discusses the deposition technique, its implementation, and the experimental results obtained to date.

  14. Dry-plasma-free chemical etch technique for variability reduction in multi-patterning (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Kal, Subhadeep; Mohanty, Nihar; Farrell, Richard A.; Franke, Elliott; Raley, Angelique; Thibaut, Sophie; Pereira, Cheryl; Pillai, Karthik; Ko, Akiteru; Mosden, Aelan; Biolsi, Peter

    2017-04-01

    features during the etch process. Herein we will also demonstrate a test case on how a combination or plasma assisted and plasma free etch techniques has the potential to improve process performance of a 193nm immersion based self aligned quandruple patterning (SAQP) for BEOL compliant films (an example shown in Fig 2). In addition, we will also present on the application of gas etches for (1) profile improvement, (2) selective mandrel pull (3) critical dimension trim of mandrels, with an analysis of advantages over conventional techniques in terms of LER and EPE.

  15. Sterile technique

    MedlinePlus

    ... technique. In: Perry AG, Potter PA, eds. Clinical Nursing Skills and Techniques . 8th ed. Philadelphia, PA: Elsevier Mosby; 2014:chap 8. Read More Stress urinary incontinence Urge incontinence Urinary incontinence Patient Instructions ...

  16. Modulation techniques

    NASA Technical Reports Server (NTRS)

    Schilling, D. L.

    1982-01-01

    Bandwidth efficient digital modulation techniques, proposed for use on and/or applied to satellite channels, are reviewed. In a survey of recent works on digital modulation techniques, the performance of several schemes operating in various environments are compared. Topics covered include: (1) quadrature phase shift keying; (2) offset - QPSK and MSK; (3) combined modulation and coding; and (4) spectrally efficient modulation techniques.

  17. Dismantling techniques

    SciTech Connect

    Wiese, E.

    1998-03-13

    Most of the dismantling techniques used in a Decontamination and Dismantlement (D and D) project are taken from conventional demolition practices. Some modifications to the techniques are made to limit exposure to the workers or to lessen the spread of contamination to the work area. When working on a D and D project, it is best to keep the dismantling techniques and tools as simple as possible. The workers will be more efficient and safer using techniques that are familiar to them. Prior experience with the technique or use of mock-ups is the best way to keep workers safe and to keep the project on schedule.

  18. Fiber Techniques

    ERIC Educational Resources Information Center

    Nalle, Leona

    1976-01-01

    Describes a course in fiber techniques, which covers design methods involving fibers and fabric, that students in the Art Department at Sleeping Giant Junior High School had the opportunity to learn. (Author/RK)

  19. Stapedectomy technique.

    PubMed

    House, J W

    1993-06-01

    This article reviews the evolution of the author's stapedectomy technique from total footplate removal with single loop wire prosthesis and Gelfoam seal to small fenestra stapedectomy with platinum ribbon piston prosthesis and blood seal. The author concludes that the microdrill is effective, safe, and cost effective for performing this procedure. Since using this technique, the author has had no cases of sensorineural hearing loss and few complaints of dizziness or vertigo.

  20. Decomposition techniques

    USGS Publications Warehouse

    Chao, T.T.; Sanzolone, R.F.

    1992-01-01

    Sample decomposition is a fundamental and integral step in the procedure of geochemical analysis. It is often the limiting factor to sample throughput, especially with the recent application of the fast and modern multi-element measurement instrumentation. The complexity of geological materials makes it necessary to choose the sample decomposition technique that is compatible with the specific objective of the analysis. When selecting a decomposition technique, consideration should be given to the chemical and mineralogical characteristics of the sample, elements to be determined, precision and accuracy requirements, sample throughput, technical capability of personnel, and time constraints. This paper addresses these concerns and discusses the attributes and limitations of many techniques of sample decomposition along with examples of their application to geochemical analysis. The chemical properties of reagents as to their function as decomposition agents are also reviewed. The section on acid dissolution techniques addresses the various inorganic acids that are used individually or in combination in both open and closed systems. Fluxes used in sample fusion are discussed. The promising microwave-oven technology and the emerging field of automation are also examined. A section on applications highlights the use of decomposition techniques for the determination of Au, platinum group elements (PGEs), Hg, U, hydride-forming elements, rare earth elements (REEs), and multi-elements in geological materials. Partial dissolution techniques used for geochemical exploration which have been treated in detail elsewhere are not discussed here; nor are fire-assaying for noble metals and decomposition techniques for X-ray fluorescence or nuclear methods be discussed. ?? 1992.

  1. Immunochemical techniques.

    PubMed

    2009-01-01

    The scope of this book does not allow a complete description of the many techniques available for purification and treatment of reagents for facilitating immunoassays in general. There is a large amount of literature covering techniques, and this can be consulted for specific problems. The examination of many of the catalogs produced by commercial companies is useful as they often include good technical sections describing methods using their products. This chapter contains the practical basics of conjugation (a large field in itself), and details other immediately useful techniques that might be first desired in starting an ELISA. The book Antibodies: A Laboratory Manual (1) should be regarded as definitive in the laboratory because it is extremely "digestible" and covers a large field of methods, all of which are relevant to ELISA.

  2. Titration Techniques

    NASA Astrophysics Data System (ADS)

    Jacobsen, Jerrold J.; Houston Jetzer, Kelly; Patani, Néha; Zimmerman, John; Zweerink, Gerald

    1995-07-01

    Significant attention is paid to the proper technique for reading a meniscus. Video shows meniscus-viewing techniques for colorless and dark liquids and the consequences of not reading a meniscus at eye level. Lessons are provided on approaching the end point, focusing on end point colors produced via different commonly used indicators. The concept of a titration curve is illustrated by means of a pH meter. Carefully recorded images of the entire range of meniscus values in a buret, pipet, and graduated cylinder are included so that you can show your students, in lecture or pre-lab discussion, any meniscus and discuss how to read the buret properly. These buret meniscus values are very carefully recorded at the rate of one video frame per hundredth of a milliliter, so that an image showing any given meniscus value can be obtained. These images can be easily incorporated into a computer-based multimedia environment for testing or meniscus-reading exercises. Two of the authors have used this technique and found the exercise to be very well received by their students. Video on side two shows nearly 100 "bloopers", demonstrating both the right way and wrong ways to do tasks associated with titration. This material can be used in a variety of situations: to show students the correct way to do something; to test students by asking them "What is this person doing wrong?"; or to develop multimedia, computer-based lessons. The contents of Titration Techniques are listed below: Side 1 Titration: what it is. A simple titration; Acid-base titration animation; A brief redox titration; Redox titration animation; A complete acid-base titration. Titration techniques. Hand technique variations; Stopcock; Using a buret to measure liquid volumes; Wait before reading meniscus; Dirty and clean burets; Read meniscus at eye level (see Fig. 1); Meniscus viewing techniques--light colored liquids; Meniscus viewing techniques--dark liquids; Using a magnetic stirrer; Rough titration

  3. Electrochemical Techniques

    SciTech Connect

    Chen, Gang; Lin, Yuehe

    2008-07-20

    Sensitive and selective detection techniques are of crucial importance for capillary electrophoresis (CE), microfluidic chips, and other microfluidic systems. Electrochemical detectors have attracted considerable interest for microfluidic systems with features that include high sensitivity, inherent miniaturization of both the detection and control instrumentation, low cost and power demands, and high compatibility with microfabrication technology. The commonly used electrochemical detectors can be classified into three general modes: conductimetry, potentiometry, and amperometry.

  4. Aseptic technique.

    PubMed

    Bykowski, Tomasz; Stevenson, Brian

    2008-11-01

    This chapter describes common laboratory procedures that can reduce the risk of culture contaminations (sepsis), collectively referred as "aseptic technique." Two major strategies of aseptic work are described: using a Bunsen burner and a laminar flow hood. Both methods are presented in the form of general protocols applicable to a variety of laboratory tasks such as pipetting and dispensing aliquots, preparing growth media, and inoculating, passaging, and spreading microorganisms on petri dishes.

  5. Management Technique

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Ball Aerospace Systems Division developed a highly efficient management method known as the "total integrated systems approach" a technique developed of necessity for managing extremely complex aerospace programs involving integration of a great many individual systems. These systems, developed at different times by many different companies, must not only work perfectly when separately tested, they must also perform compatibly when integrated into the complete prime system. Systems approach is essentially a carefully considered, painstakingly executed master plan for coordinated design, development and assembly of the multitude of elements that constitute the end product. Intent is to eliminate problems that may occur when specific parts of total functioning system fail to come together to provide the requisite performance of the prime system.

  6. Shrink tape technique for heat-forming aluminum substrates for thin foil x-ray mirrors and the Neutron Star Interior Composition Explorer x-ray concentrators

    NASA Astrophysics Data System (ADS)

    Balsamo, Erin; Gendreau, Keith; Okajima, Takashi; Soong, Yang; Serlemitsos, Peter; Jalota, Lalit; Kenyon, Steven; Spartana, Nicholas; Fickau, David; Koenecke, Richard

    2016-01-01

    Consistent improvements in the design and fabrication of thin-foil, epoxy-replicated x-ray mirrors for astronomical telescopes have yielded increasingly higher quality and more precise astrophysical data. The Neutron Star Interior Composition Explorer (NICER) x-ray timing mission optics continues this tradition and introduces design elements that promise even more accurate measurements and precise astrophysical parameters. The singly reflecting concentrators have a curved axial profile to improve photon concentration and a sturdy full shell structure for enhanced module stability. These design elements introduced the challenge of reliably forming mirror substrates at an acceptable production rate. By developing a technique using heat shrink tape to compress and conform thin aluminum mirror substrates to shaping mandrels, production rate improved with successful fabrication. The technique's efficiency was analyzed by measuring hundreds of substrate profiles postforming, performance testing completely assembled concentrators composed of every size substrate, and comparing the results to simulated fabrication scenarios. On average, the profiles were copied within 4.6±3.7%. These measurements and the overall success of NICER's optics, via ground calibration, have shown that the heat-shrink tape method is reliable, repeatable, and could be used in future missions to increase production rate and improve performance.

  7. Analytical techniques: A compilation

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A compilation, containing articles on a number of analytical techniques for quality control engineers and laboratory workers, is presented. Data cover techniques for testing electronic, mechanical, and optical systems, nondestructive testing techniques, and gas analysis techniques.

  8. Mesoscopic spatial designs of nano- and microfiber meshes for tissue-engineering matrix and scaffold based on newly devised multilayering and mixing electrospinning techniques.

    PubMed

    Kidoaki, Satoru; Kwon, Il Kuen; Matsuda, Takehisa

    2005-01-01

    To design a mesoscopically ordered structure of the matrices and scaffolds composed of nano- and microscale fiber meshes for artificial and tissue-engineering devices, two new electrospinning techniques are proposed: multilayering electrospinning and mixing electrospinning. First, the following four kinds of component polymers were individually electrospun to determine the conditions for producing stable nano- and microfibers by optimizing the formulation parameters (solvent and polymer concentration) and operation parameters (voltage, air gap, and flow rate) for each polymer: (a) type I collagen, (b) styrenated gelatin (ST-gelatin), (c) segmented polyurethane (SPU), and (d) poly(ethylene oxide). A trilayered electrospun mesh, in which individual fiber meshes (type I collagen, ST-gelatin, and SPU) were deposited layer by layer, was formed by sequential electrospinning; this was clearly visualized by confocal laser scanning microscopy. The mixed electrospun-fiber mesh composed of SPU and PEO was prepared by simultaneous electrospinning on a stainless-steel mandrel with high-speed rotation and traverse movement. A bilayered tubular construct composed of a thick SPU microfiber mesh as an outer layer and a thin type I collagen nanofiber mesh as an inner layer was fabricated as a prototype scaffold of artificial grafts, and visualized by scanning electron microscopy.

  9. Aerodynamic measurement techniques. [laser based diagnostic techniques

    NASA Technical Reports Server (NTRS)

    Hunter, W. W., Jr.

    1976-01-01

    Laser characteristics of intensity, monochromatic, spatial coherence, and temporal coherence were developed to advance laser based diagnostic techniques for aerodynamic related research. Two broad categories of visualization and optical measurements were considered, and three techniques received significant attention. These are holography, laser velocimetry, and Raman scattering. Examples of the quantitative laser velocimeter and Raman scattering measurements of velocity, temperature, and density indicated the potential of these nonintrusive techniques.

  10. Radiologic imaging technique

    SciTech Connect

    Bushong, S.C. ); Eastman, T.R. )

    1990-01-01

    The authors focus on the subject of clinical radiographic technique. Emphasizing correct radiographic technique, it's heavily illustrated with radiographs that demonstrate proper exposure and show what happens when exposure variables are changed. A key feature is a discussion and evaluation of radiographic technique charts. Basic technique charts are provided for every body part examined.

  11. Data analysis techniques

    NASA Technical Reports Server (NTRS)

    Park, Steve

    1990-01-01

    A large and diverse number of computational techniques are routinely used to process and analyze remotely sensed data. These techniques include: univariate statistics; multivariate statistics; principal component analysis; pattern recognition and classification; other multivariate techniques; geometric correction; registration and resampling; radiometric correction; enhancement; restoration; Fourier analysis; and filtering. Each of these techniques will be considered, in order.

  12. Tools & techniques--statistics: propensity score techniques.

    PubMed

    da Costa, Bruno R; Gahl, Brigitta; Jüni, Peter

    2014-10-01

    Propensity score (PS) techniques are useful if the number of potential confounding pretreatment variables is large and the number of analysed outcome events is rather small so that conventional multivariable adjustment is hardly feasible. Only pretreatment characteristics should be chosen to derive PS, and only when they are probably associated with outcome. A careful visual inspection of PS will help to identify areas of no or minimal overlap, which suggests residual confounding, and trimming of the data according to the distribution of PS will help to minimise residual confounding. Standardised differences in pretreatment characteristics provide a useful check of the success of the PS technique employed. As with conventional multivariable adjustment, PS techniques cannot account for confounding variables that are not or are only imperfectly measured, and no PS technique is a substitute for an adequately designed randomised trial.

  13. The radiocarbon hydroxyl technique

    NASA Technical Reports Server (NTRS)

    Campbell, Malcolm J.; Sheppard, John C.

    1994-01-01

    The Radiocarbon Technique depends upon measuring the rate of oxidation of CO in an essentially unperturbed sample of air. The airborne technique is slightly different. Hydroxyl concentrations can be calculated directly; peroxyl concentrations can be obtained by NO doping.

  14. Seals and Sealing Techniques

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Developments by the aerospace industry in seals and sealing techniques are announced for possible use in other areas. The announcements presented are grouped as: sealing techniques for cryogenic fluids, high pressure applications, and modification for improved performance.

  15. Nondestructive evaluation technique guide

    NASA Technical Reports Server (NTRS)

    Vary, A.

    1973-01-01

    A total of 70 individual nondestructive evaluation (NDE) techniques are described. Information is presented that permits ease of comparison of the merits and limitations of each technique with respect to various NDE problems. An NDE technique classification system is presented. It is based on the system that was adopted by the National Materials Advisory Board (NMAB). The classification system presented follows the NMAB system closely with the exception of additional categories that have been added to cover more advanced techniques presently in use. The rationale of the technique is explained. The format provides for a concise description of each technique, the physical principles involved, objectives of interrogation, example applications, limitations of each technique, a schematic illustration, and key reference material. Cross-index tabulations are also provided so that particular NDE problems can be referred to appropriate techniques.

  16. The radiocarbon hydroxyl technique

    NASA Technical Reports Server (NTRS)

    Campbell, Malcolm J.; Sheppard, John C.

    1994-01-01

    The Radiocarbon Technique depends upon measuring the rate of oxidation of CO in an essentially unperturbed sample of air. The airborne technique is slightly different. Hydroxyl concentrations can be calculated directly; peroxyl concentrations can be obtained by NO doping.

  17. Corrective Primary Impression Technique

    PubMed Central

    Fernandes, Aquaviva; Dua, Neha; Herekar, Manisha

    2010-01-01

    The article describes a simple, quick and corrective technique for making the preliminary impression. It records the extensions better as compared to the impressions made using only impression compound. This technique is accurate and gives properly extended custom tray. Any deficiencies seen in the compound primary impression are corrected using this technique hence, this technique is called as a “corrective primary impression technique”. PMID:20502648

  18. Drilling technique for crystals

    NASA Technical Reports Server (NTRS)

    Hunter, T.; Miyagawa, I.

    1977-01-01

    Hole-drilling technique uses special crystal driller in which drill bit rotates at fixed position at speed of 30 rpm while crystal slowly advances toward drill. Technique has been successfully applied to crystal of Rochell salt, Triglycine sulfate, and N-acetyglycine. Technique limits heat buildup and reduces strain on crystal.

  19. The backcross sterility technique

    Treesearch

    V. C. Mastro; A. Pellegrini-Toole

    1991-01-01

    The sterile insect technique (SIT) and the induced inherited (F1) sterility technique have been investigated for a number of lepidopterous pests, including the gypsy moths. Another technique, backcross sterility, which could potentially prove as or more useful for control of pest species has been developed for the control of only one lepidopteran...

  20. Techniques for characterizing lignin

    Treesearch

    Nicole M. Stark; Daniel J. Yelle; Umesh P. Agarwal

    2016-01-01

    Many techniques are available to characterize lignin. The techniques presented in this chapter are considered nondegradative, which are commonly applied to lignin. A brief discussion of lignin structure is included with this chapter to aid the reader in understanding why the discussed characterization techniques are appropriate for the study of lignin. Because the...

  1. Imaging technologies and techniques.

    PubMed

    Rafter, Patrick; Phillips, Patrick; Vannan, Mani A

    2004-05-01

    Equipment manufacturers provide contrast-specific detection techniques that have excellent sensitivity and excellent agent-to-tissue specificity along with helpful tools that improve workflow efficiency dramatically. Excellent contrast agents have been approved for LV opacification and are available worldwide. Techniques designed for low-MI imaging offer real-time acquisition capabilities and lead to faster examinations. Techniques designed for medium-MI imaging offer better sensitivity than low-MI techniques while maintaining the benefit of rapid image acquisition. Techniques designed for high-MI imaging offer the best sensitivity with longer acquisition times. These techniques are viable means for imaging contrast agents tailored to clinical needs. Progress by contrast agent manufacturers, equipment manufacturers, and physicians will continue to drive improvements in the areas of detection and clinical workflow for improved patient care.

  2. Hot techniques for tonsillectomy.

    PubMed

    Scott, A

    2006-11-01

    (1) Some patients experience pain and bleeding after a standard or extracapsular tonsillectomy. (2) Evidence suggests that none of the hot tonsillectomy techniques offers concurrent reductions in intra- and post-operative bleeding and pain, compared with traditional cold-steel dissection with packs or ties. (3) Little information is available on the cost effectiveness of the hot techniques. (4) Diathermy is likely to remain the most commonly practised hot tonsillectomy technique.

  3. Rocket performance prediction technique

    NASA Technical Reports Server (NTRS)

    Morgenthaler, J. H.; Stepien, W. R.

    1974-01-01

    Attention is given to a semiempirical correlation technique based on the rational assumption that the turbulent mixing of reactants is the rate controlling process in combustors employing diffusion flames. Questions of performance computation are considered along with the flow conditions. Predictions of combustion efficiency are obtained with the aid of a standard finite-difference computational technique.-

  4. Techniques for Teachers Section

    ERIC Educational Resources Information Center

    Tait, A., Ed.

    1973-01-01

    Includes a simple technique to demonstrate Millikan's oil drop experiment, an environmental studies experiment to measure dissolved oxygen in water samples, and a technique to demonstrate action-reaction. Science materials described are the Pol-A-Star Tomiscope, Nuffield chemistry film loops, air pucks and pH meters. (JR)

  5. Techniques for Teachers Section

    ERIC Educational Resources Information Center

    Tait, A., Ed.

    1973-01-01

    Includes a simple technique to demonstrate Millikan's oil drop experiment, an environmental studies experiment to measure dissolved oxygen in water samples, and a technique to demonstrate action-reaction. Science materials described are the Pol-A-Star Tomiscope, Nuffield chemistry film loops, air pucks and pH meters. (JR)

  6. Contamination Control Techniques

    SciTech Connect

    EBY, J.L.

    2000-05-16

    Welcome to a workshop on contamination Control techniques. This work shop is designed for about two hours. Attendee participation is encouraged during the workshop. We will address different topics within contamination control techniques; present processes, products and equipment used here at Hanford and then open the floor to you, the attendees for your input on the topics.

  7. Flight Test Techniques

    DTIC Science & Technology

    2009-07-01

    Fort Rucker, AL 36362-5276 8. PERFORMING ORGANIZATION REPORT NUMBER TOP 7-4-020 9. SPONSORING/ MONITORING AGENCY NAME(S) AND ADDRESS(ES...2 3. REQUIRED TEST CONDITIONS ............................................. 3 3.1...3. REQUIRED TEST CONDITIONS . 3.1 Air Vehicle Flight Test Techniques. Many different flight test techniques are in existence. As technology

  8. Offshore hydraulic fracturing technique

    SciTech Connect

    Meese, C.A. ); Mullen, M.E. ); Barree, R.D. )

    1994-03-01

    This paper describes the frac-and-pack completion technique currently being used in the Gulf of Mexico, and elsewhere, for stimulation and sand control. The paper describes process applications and concerns that arise during implementation of the technique and discusses the completion procedure, treatment design, and execution.

  9. TECHNIQUES FOR EFFECTIVE TEACHING.

    ERIC Educational Resources Information Center

    HASTINGS, GERALDINE; AND OTHERS

    A COMPENDIUM OF WORKABLE AND REASONABLE TECHNIQUES TO PROVIDE TEACHERS WITH ALTERNATIVES IN SELECTING LEARNING EXPERIENCES IS PRESENTED. MATERIALS ARE DESIGNED TO AID TEACHERS AND LEARNERS IN ALL SUBJECT MATTER AREAS. TEACHING TECHNIQUES DESCRIBED ARE (1) THE CASE STUDY, (2) DISCUSSIONS SUCH AS SYMPOSIUM, COLLOQUIUM, BUZZ SESSIONS, AND…

  10. The Schlieren Technique

    NASA Astrophysics Data System (ADS)

    Eder, Andreas; Jordan, Martin

    Introduction Basic Principle Optical and Thermodynamic Interrelations Refraction Index and Temperature Field The Deflection of Light in an Inhomogeneous Medium Application of the Schlieren Technique Application to Transient Combustion Research The Schlieren Cinematography The Color Schlieren Technique Application to Fuel-Injection Systems

  11. UIAGM Ropehandling Techniques.

    ERIC Educational Resources Information Center

    Cloutier, K. Ross

    The Union Internationale des Associations des Guides de Montagne's (UIAGM) rope handling techniques are intended to form the standard for guiding ropework worldwide. These techniques have become the legal standard for instructional institutions and commercial guiding organizations in UIAGM member countries: Austria, Canada, France, Germany, Great…

  12. Emerging optical nanoscopy techniques

    PubMed Central

    Montgomery, Paul C; Leong-Hoi, Audrey

    2015-01-01

    To face the challenges of modern health care, new imaging techniques with subcellular resolution or detection over wide fields are required. Far field optical nanoscopy presents many new solutions, providing high resolution or detection at high speed. We present a new classification scheme to help appreciate the growing number of optical nanoscopy techniques. We underline an important distinction between superresolution techniques that provide improved resolving power and nanodetection techniques for characterizing unresolved nanostructures. Some of the emerging techniques within these two categories are highlighted with applications in biophysics and medicine. Recent techniques employing wider angle imaging by digital holography and scattering lens microscopy allow superresolution to be achieved for subcellular and even in vivo, imaging without labeling. Nanodetection techniques are divided into four subcategories using contrast, phase, deconvolution, and nanomarkers. Contrast enhancement is illustrated by means of a polarized light-based technique and with strobed phase-contrast microscopy to reveal nanostructures. Very high sensitivity phase measurement using interference microscopy is shown to provide nanometric surface roughness measurement or to reveal internal nanometric structures. Finally, the use of nanomarkers is illustrated with stochastic fluorescence microscopy for mapping intracellular structures. We also present some of the future perspectives of optical nanoscopy. PMID:26491270

  13. Techniques for Learning Vocabulary.

    ERIC Educational Resources Information Center

    Weatherford, H. Jarold

    A variety of classroom techniques for second language vocabulary learning are described, based on the principle that different approaches work with different students under varying conditions. The techniques include: rote rehearsal; the use of visual aids, including items that are acted out by students for the benefit of the class; role-playing;…

  14. Simulation verification techniques study

    NASA Technical Reports Server (NTRS)

    Schoonmaker, P. B.; Wenglinski, T. H.

    1975-01-01

    Results are summarized of the simulation verification techniques study which consisted of two tasks: to develop techniques for simulator hardware checkout and to develop techniques for simulation performance verification (validation). The hardware verification task involved definition of simulation hardware (hardware units and integrated simulator configurations), survey of current hardware self-test techniques, and definition of hardware and software techniques for checkout of simulator subsystems. The performance verification task included definition of simulation performance parameters (and critical performance parameters), definition of methods for establishing standards of performance (sources of reference data or validation), and definition of methods for validating performance. Both major tasks included definition of verification software and assessment of verification data base impact. An annotated bibliography of all documents generated during this study is provided.

  15. Techniques of hepatic resection

    PubMed Central

    Aragon, Robert J.

    2012-01-01

    Liver resections are high risk procedures performed by experienced surgeons. The role of liver resection in malignant disease has changed over the last 100 years with great improvement in morbidity, mortality and long term survival. New understanding in liver anatomy, improved perioperative care, anesthesia techniques, and technological advances has improved this aspect of patient care. With improved techniques, patients previously considered unresectable have an opportunity to undergo curative surgery. This review article describes the various approaches and techniques for liver resection. The relevant anatomy and terminology of hepatic resections is discussed, as well as the role of anatomic vs. nonanatomic resection. Methods of vascular control are examined and the multiple strategies of parenchymal transection are compared, as well as minimally-invasive techniques. Finally, a brief review of the authors’ practice in terms of surgical technique is offered. PMID:22811867

  16. [New microbiological techniques].

    PubMed

    Schubert, S; Wieser, A; Bonkat, G

    2017-06-01

    Microbiological diagnostic procedures have changed rapidly in recent years. This is especially true in the field of molecular diagnostics. Classical culture-based techniques are still the gold standard in many areas; however, they are already complemented by automated and also molecular techniques to guarantee faster and better quality results. The most commonly used techniques include real-time polymerase chain reaction (RT-PCR) based systems and nucleic acid hybridization. These procedures are used most powerfully from direct patient samples or in assays to detect the presence of nonculturable or fastidious organisms. Further techniques such as DNA sequencing are not yet used routinely for urological samples and can be considered experimental. However, in conjunction with dropping prices and further technical developments, these techniques promise to be used much more in the near future. Regarding bacterial identification from culture, mass spectrometry (MALDI-TOF MS) has become the technique of choice in recent years especially in Europe. It has tremendously shortened the time to result. This is now going to be extended to antibiotic susceptibility testing. This is of paramount importance in view of ever rising antimicrobial resistance rates. Techniques described in this review offer a faster and better microbiological diagnosis. Such continuous improvements are critical especially in times of cost pressure and rising antimicrobial resistance rates. It is in our interest to provide the best possible care for patients and in this regard a good and effective communication between the laboratory and the clinician is of vital importance.

  17. Separation techniques: Chromatography

    PubMed Central

    Coskun, Ozlem

    2016-01-01

    Chromatography is an important biophysical technique that enables the separation, identification, and purification of the components of a mixture for qualitative and quantitative analysis. Proteins can be purified based on characteristics such as size and shape, total charge, hydrophobic groups present on the surface, and binding capacity with the stationary phase. Four separation techniques based on molecular characteristics and interaction type use mechanisms of ion exchange, surface adsorption, partition, and size exclusion. Other chromatography techniques are based on the stationary bed, including column, thin layer, and paper chromatography. Column chromatography is one of the most common methods of protein purification. PMID:28058406

  18. Electrical termination techniques

    NASA Technical Reports Server (NTRS)

    Oakey, W. E.; Schleicher, R. R.

    1976-01-01

    A technical review of high reliability electrical terminations for electronic equipment was made. Seven techniques were selected from this review for further investigation, experimental work, and preliminary testing. From the preliminary test results, four techniques were selected for final testing and evaluation. These four were: (1) induction soldering, (2) wire wrap, (3) percussive arc welding, and (4) resistance welding. Of these four, induction soldering was selected as the best technique in terms of minimizing operator errors, controlling temperature and time, minimizing joint contamination, and ultimately producing a reliable, uniform, and reusable electrical termination.

  19. Adaptive algebraic reconstruction technique

    SciTech Connect

    Lu Wenkai; Yin Fangfang

    2004-12-01

    Algebraic reconstruction techniques (ART) are iterative procedures for reconstructing objects from their projections. It is proven that ART can be computationally efficient by carefully arranging the order in which the collected data are accessed during the reconstruction procedure and adaptively adjusting the relaxation parameters. In this paper, an adaptive algebraic reconstruction technique (AART), which adopts the same projection access scheme in multilevel scheme algebraic reconstruction technique (MLS-ART), is proposed. By introducing adaptive adjustment of the relaxation parameters during the reconstruction procedure, one-iteration AART can produce reconstructions with better quality, in comparison with one-iteration MLS-ART. Furthermore, AART outperforms MLS-ART with improved computational efficiency.

  20. Active cleaning technique device

    NASA Technical Reports Server (NTRS)

    Shannon, R. L.; Gillette, R. B.

    1973-01-01

    The objective of this program was to develop a laboratory demonstration model of an active cleaning technique (ACT) device. The principle of this device is based primarily on the technique for removing contaminants from optical surfaces. This active cleaning technique involves exposing contaminated surfaces to a plasma containing atomic oxygen or combinations of other reactive gases. The ACT device laboratory demonstration model incorporates, in addition to plasma cleaning, the means to operate the device as an ion source for sputtering experiments. The overall ACT device includes a plasma generation tube, an ion accelerator, a gas supply system, a RF power supply and a high voltage dc power supply.

  1. Special mandrel permits uniform welding of out-of-round tubing

    NASA Technical Reports Server (NTRS)

    Dor, M. E.; Fueg, L. B.; Whiffen, E. L.

    1966-01-01

    Clamp holds irregularly shaped pieces in lathe chuck without damage and eliminates excessive time in selecting optimum mounting. Interchangeable jaws ride in standard jaw slots but swivel so that the jaw face bears evenly against the workpiece regardless of contour. The jaws can be used on both engine and turret lathes.

  2. Feasibility of organo-beryllium target mandrels using organo-germanium PECVD as a surrogate

    SciTech Connect

    Brusasco, R.M.; Dittrich, T.; Cook, R.C.

    1995-03-09

    Inertial Confinement Fusion capsules incorporating beryllium are becoming attractive for use in implosion experiments designed for modest energy gain. This paper explores the feasibility of chemical vapor deposition of organo-beryllium precursors to form coating materials of interest as ablators and fuel containers. Experiments were performed in a surrogate chemical system utilizing tetramethylgermane as the organometallic precursor. Coatings with up to 60 mole percent germanium were obtained. These coatings compare favorably with those previously reported in the literature and provide increasing confidence that a similar deposition process with an organo-beryllium precursor would be successful.

  3. Techniques for managing quality.

    PubMed

    Plsek, P E

    1995-01-01

    The science of quality management is an eclectic collection of concepts and methods primarily borrowed from other fields. Techniques roughly fall into three categories involving quality improvement, planning, and measurement. Improvement techniques include models to guide team-based efforts, tools for process description, and tools for data analysis. These methods are the most visible artifacts of CQI efforts in health care organizations today. Less widely known, but equally powerful, are the techniques of quality planning. There are models to guide both process design and strategic planning, methods for identifying customer needs, and tools to support these efforts. Finally, while measurement is a traditionally well-developed area in health care, industrial quality management science broadens our outlook about what is important to measure. It also provides the technique of benchmarking, which suggests that we look beyond our own organization when we measure performance.

  4. The MST Radar Technique

    NASA Technical Reports Server (NTRS)

    Balsley, B. B.

    1985-01-01

    The past ten year have witnessed the development of a new radar technique to examine the structure and dynamics of the atmosphere between roughly 1 to 100 km on a continuous basis. The technique is known as the MST (for Mesosphere-Stratosphere-Troposphere) technique and is usable in all weather conditions, being unaffected by precipitation or cloud cover. MST radars make use of scattering from small scale structure in the atmospheric refractive index, with scales of the order of one-half the radar wavelength. Pertinent scale sizes for middle atmospheric studies typically range between a fraction of a meter and a few meters. The structure itself arises primarily from atmospheric turbulence. The technique is briefly described along with the meteorological parameters it measures.

  5. Programs, Materials and Techniques

    ERIC Educational Resources Information Center

    Bannatyne, Alex, Ed.

    1973-01-01

    Evaluated are four commercial programs and one technique for use with learning disabled children: the KeyMath Diagnostic Arithmetic Test, Learning by Doing, the Peabody Rebus Reading Program, Jumping Up and Down, and the use of a stopwatch. (DB)

  6. "Techniques for Teachers" Section

    ERIC Educational Resources Information Center

    Tait, A.

    1972-01-01

    A series of short articles describe a method of combined developing/fixing for monochrome film, techniques for thin layer chromatography, experiments with lasers, and safety precautions to be used with lasers in school laboratories. (AL)

  7. Relaxation techniques for stress

    MedlinePlus

    ... problems such as high blood pressure, stomachaches, headaches, anxiety, and depression. Using relaxation techniques can help you feel calm. These exercises can also help you manage stress and ease ...

  8. Small Scale Organic Techniques

    ERIC Educational Resources Information Center

    Horak, V.; Crist, DeLanson R.

    1975-01-01

    Discusses the advantages of using small scale experimentation in the undergraduate organic chemistry laboratory. Describes small scale filtration techniques as an example of a semi-micro method applied to small quantities of material. (MLH)

  9. "Techniques for Teachers" Section

    ERIC Educational Resources Information Center

    Tait, A.

    1972-01-01

    A series of short articles describe a method of combined developing/fixing for monochrome film, techniques for thin layer chromatography, experiments with lasers, and safety precautions to be used with lasers in school laboratories. (AL)

  10. Pattern recognition technique

    NASA Technical Reports Server (NTRS)

    Hong, J. P.

    1971-01-01

    Technique operates regardless of pattern rotation, translation or magnification and successfully detects out-of-register patterns. It improves accuracy and reduces cost of various optical character recognition devices and page readers and provides data input to computer.

  11. Occlusal cranial balancing technique.

    PubMed

    Smith, Gerald H

    2007-01-01

    The acronym for Occlusal Cranial Balancing Technique is OCB. The OCB concept is based on the architectural principle of a level foundation. The principles of Occlusal Cranial Balancing are a monumental discovery and if applied will enhance total body function.

  12. Monitoring by Control Technique

    EPA Pesticide Factsheets

    Stationary source emissions monitoring is required to demonstrate that a source is meeting the requirements in Federal or state rules. This page links to different control techniques used to reduce pollutant emissions.

  13. Next generation initiation techniques

    NASA Technical Reports Server (NTRS)

    Warner, Tom; Derber, John; Zupanski, Milija; Cohn, Steve; Verlinde, Hans

    1993-01-01

    Four-dimensional data assimilation strategies can generally be classified as either current or next generation, depending upon whether they are used operationally or not. Current-generation data-assimilation techniques are those that are presently used routinely in operational-forecasting or research applications. They can be classified into the following categories: intermittent assimilation, Newtonian relaxation, and physical initialization. It should be noted that these techniques are the subject of continued research, and their improvement will parallel the development of next generation techniques described by the other speakers. Next generation assimilation techniques are those that are under development but are not yet used operationally. Most of these procedures are derived from control theory or variational methods and primarily represent continuous assimilation approaches, in which the data and model dynamics are 'fitted' to each other in an optimal way. Another 'next generation' category is the initialization of convective-scale models. Intermittent assimilation systems use an objective analysis to combine all observations within a time window that is centered on the analysis time. Continuous first-generation assimilation systems are usually based on the Newtonian-relaxation or 'nudging' techniques. Physical initialization procedures generally involve the use of standard or nonstandard data to force some physical process in the model during an assimilation period. Under the topic of next-generation assimilation techniques, variational approaches are currently being actively developed. Variational approaches seek to minimize a cost or penalty function which measures a model's fit to observations, background fields and other imposed constraints. Alternatively, the Kalman filter technique, which is also under investigation as a data assimilation procedure for numerical weather prediction, can yield acceptable initial conditions for mesoscale models. The

  14. Nondestructive testing techniques

    NASA Astrophysics Data System (ADS)

    Bray, Don E.; McBride, Don

    A comprehensive reference covering a broad range of techniques in nondestructive testing is presented. Based on years of extensive research and application at NASA and other government research facilities, the book provides practical guidelines for selecting the appropriate testing methods and equipment. Topics discussed include visual inspection, penetrant and chemical testing, nuclear radiation, sonic and ultrasonic, thermal and microwave, magnetic and electromagnetic techniques, and training and human factors. (No individual items are abstracted in this volume)

  15. Method and apparatus for heat extraction by controlled spray cooling

    DOEpatents

    Edwards, Christopher Francis; Meeks, Ellen; Kee, Robert; McCarty, Kevin

    1999-01-01

    Two solutions to the problem of cooling a high temperature, high heat flux surface using controlled spray cooling are presented for use on a mandrel. In the first embodiment, spray cooling is used to provide a varying isothermal boundary layer on the side portions of a mandrel by providing that the spray can be moved axially along the mandrel. In the second embodiment, a spray of coolant is directed to the lower temperature surface of the mandrel. By taking advantage of super-Leidenfrost cooling, the temperature of the high temperature surface of the mandrel can be controlled by varying the mass flux rate of coolant droplets. The invention has particular applicability to the field of diamond synthesis using chemical vapor deposition techniques.

  16. Percutaneous techniques versus surgical techniques for tracheostomy.

    PubMed

    Brass, Patrick; Hellmich, Martin; Ladra, Angelika; Ladra, Jürgen; Wrzosek, Anna

    2016-07-20

    Tracheostomy formation is one of the most commonly performed surgical procedures in critically ill intensive care participants requiring long-term mechanical ventilation. Both surgical tracheostomies (STs) and percutaneous tracheostomies (PTs) are used in current surgical practice; but until now, the optimal method of performing tracheostomies in critically ill participants remains unclear. We evaluated the effectiveness and safety of percutaneous techniques compared to surgical techniques commonly used for elective tracheostomy in critically ill participants (adults and children) to assess whether there was a difference in complication rates between the procedures. We also assessed whether the effect varied between different groups of participants or settings (intensive care unit (ICU), operating room), different levels of operator experience, different percutaneous techniques, or whether the percutaneous techniques were carried out with or without bronchoscopic guidance. We searched the following electronic databases: CENTRAL, MEDLINE, EMBASE, and CINAHL to 28 May 2015. We also searched reference lists of articles, 'grey literature', and dissertations. We handsearched intensive care and anaesthesia journals, abstracts, and proceedings of scientific meetings. We attempted to identify unpublished or ongoing studies by contacting manufacturers and experts in the field, and searching in trial registers. We included randomized and quasi-randomized controlled trials (quasi-RCTs) comparing percutaneous techniques (experimental intervention) with surgical techniques (control intervention) used for elective tracheostomy in critically ill participants (adults and children). Three authors independently checked eligibility and extracted data on methodological quality, participant characteristics, intervention details, settings, and outcomes of interest using a standardized form. We then entered data into Review Manager 5, with a double-entry procedure. Of 785 identified

  17. Techniques of male circumcision.

    PubMed

    Abdulwahab-Ahmed, Abdullahi; Mungadi, Ismaila A

    2013-01-01

    Male circumcision is a controversial subject in surgical practice. There are, however, clear surgical indications of this procedure. The American Academy of Pediatrics (AAP) recommends newborn male circumcision for its preventive and public health benefits that has been shown to outweigh the risks of newborn male circumcision. Many surgical techniques have been reported. The present review discusses some of these techniques with their merits and drawbacks. This is an attempt to inform the reader on surgical aspects of male circumcision aiding in making appropriate choice of a technique to offer patients. Pubmed search was done with the keywords: Circumcision, technique, complications, and history. Relevant articles on techniques of circumcision were selected for the review. Various methods of circumcision including several devices are in use for male circumcision. These methods can be grouped into three: Shield and clamp, dorsal slit, and excision. The device methods appear favored in the pediatric circumcision while the risk of complications increases with increasing age of the patient at surgery.

  18. Renal imaging techniques.

    PubMed

    Hierholzer, K; Hierholzer, J

    1997-01-01

    The ancient approach to obtain an image of the kidneys (and other internal organs) was 'section-inspection-imaging' by drawing, painting, sculpturing, and modelling. The present study follows chronologically the development and use of sectioning techniques from ancient (often forbidden) methods to modern microdissection and maceration of silicone-rubber-injected tubules. Inspection evolved from the use of the naked eye to magnifying lenses, microscopes and finally electron microscopy. Pertinent examples such as the description of the kidneys as the site of urine formation, the visualization of loop structures in the renal medulla and the imaging of tight junction strands are discussed. Inspection or visualization of renal structure and function has been revolutionized by modern noninvasive techniques, such as X-ray imaging, imaging by radioisotopes, ultrasound, computer tomography and nuclear magnetic resonance. Pertinent examples are given demonstrating the potency of the various techniques. The contribution of computerized data evaluation is discussed. The development of micropuncture and microperfusion techniques has opened the field for direct imaging not only of renal (sub)structural details but also of functional parameters such as transtubular reabsorption rates, single glomerular capillary filtration and conductance of the paracellular pathway. We focus particularly on techniques specifically designed to visualize renal hemodynamic and transport parameters.

  19. Sensorimotor System Measurement Techniques

    PubMed Central

    Riemann, Bryan L.; Myers, Joseph B.; Lephart, Scott M.

    2002-01-01

    Objective: To provide an overview of currently available sensorimotor assessment techniques. Data Sources: We drew information from an extensive review of the scientific literature conducted in the areas of proprioception, neuromuscular control, and motor control measurement. Literature searches were conducted using MEDLINE for the years 1965 to 1999 with the key words proprioception, somatosensory evoked potentials, nerve conduction testing, electromyography, muscle dynamometry, isometric, isokinetic, kinetic, kinematic, posture, equilibrium, balance, stiffness, neuromuscular, sensorimotor, and measurement. Additional sources were collected using the reference lists of identified articles. Data Synthesis: Sensorimotor measurement techniques are discussed with reference to the underlying physiologic mechanisms, influential factors and locations of the variable within the system, clinical research questions, limitations of the measurement technique, and directions for future research. Conclusions/Recommendations: The complex interactions and relationships among the individual components of the sensorimotor system make measuring and analyzing specific characteristics and functions difficult. Additionally, the specific assessment techniques used to measure a variable can influence attained results. Optimizing the application of sensorimotor research to clinical settings can, therefore, be best accomplished through the use of common nomenclature to describe underlying physiologic mechanisms and specific measurement techniques. PMID:16558672

  20. Relaxation Techniques for Trauma.

    PubMed

    Scotland-Coogan, Diane; Davis, Erin

    2016-01-01

    Physiological symptoms of posttraumatic stress disorder (PTSD) manifest as increased arousal and reactivity seen as anger outburst, irritability, reckless behavior with no concern for consequences, hypervigilance, sleep disturbance, and problems with focus (American Psychiatric Association, 2013 ). In seeking the most beneficial treatment for PTSD, consideration must be given to the anxiety response. Relaxation techniques are shown to help address the physiological manifestations of prolonged stress. The techniques addressed by the authors in this article include mindfulness, deep breathing, yoga, and meditation. By utilizing these techniques traditional therapies can be complemented. In addition, those who are averse to the traditional evidence-based practices or for those who have tried traditional therapies without success; these alternative interventions may assist in lessening physiological manifestations of PTSD. Future research studies assessing the benefits of these treatment modalities are warranted to provide empirical evidence to support the efficacy of these treatments.

  1. Mathematical Optimization Techniques

    NASA Technical Reports Server (NTRS)

    Bellman, R. (Editor)

    1963-01-01

    The papers collected in this volume were presented at the Symposium on Mathematical Optimization Techniques held in the Santa Monica Civic Auditorium, Santa Monica, California, on October 18-20, 1960. The objective of the symposium was to bring together, for the purpose of mutual education, mathematicians, scientists, and engineers interested in modern optimization techniques. Some 250 persons attended. The techniques discussed included recent developments in linear, integer, convex, and dynamic programming as well as the variational processes surrounding optimal guidance, flight trajectories, statistical decisions, structural configurations, and adaptive control systems. The symposium was sponsored jointly by the University of California, with assistance from the National Science Foundation, the Office of Naval Research, the National Aeronautics and Space Administration, and The RAND Corporation, through Air Force Project RAND.

  2. [Foetal sampling techniques].

    PubMed

    Levy, R; Arfi, J-S; Daffos, F

    2003-06-01

    This article describes the current techniques of foetal sampling. All of them are actually ultrasound guided, and therefore generally very safe. Nevertheless, an elaborate learning process remains indispensable, in addition to a particular attention to the quality of the physician-patient dialogue. The choice of a technique depends on the indication and on the term of the pregnancy. The most frequently used technique is amniocentesis which presents a low risk of foetal loss, estimated between 0.2 and 0.5 percent. The interest of chorionic villus sampling is the possibility to obtain results at an earlier stage of pregnancy, with a lower risk taking when compared to early amniocentesis. We prefer the transabdominal chorionic villus sampling to the transvaginal. Foetal blood sampling is still required in some cases, but the risk of complications is higher--around 1 percent.

  3. Radiation techniques for acromegaly

    PubMed Central

    2011-01-01

    Radiotherapy (RT) remains an effective treatment in patients with acromegaly refractory to medical and/or surgical interventions, with durable tumor control and biochemical remission; however, there are still concerns about delayed biochemical effect and potential late toxicity of radiation treatment, especially high rates of hypopituitarism. Stereotactic radiotherapy has been developed as a more accurate technique of irradiation with more precise tumour localization and consequently a reduction in the volume of normal tissue, particularly the brain, irradiated to high radiation doses. Radiation can be delivered in a single fraction by stereotactic radiosurgery (SRS) or as fractionated stereotactic radiotherapy (FSRT) in which smaller doses are delivered over 5-6 weeks in 25-30 treatments. A review of the recent literature suggests that pituitary irradiation is an effective treatment for acromegaly. Stereotactic techniques for GH-secreting pituitary tumors are discussed with the aim to define the efficacy and potential adverse effects of each of these techniques. PMID:22136376

  4. Remote Raman measurement techniques

    NASA Technical Reports Server (NTRS)

    Leonard, D. A.

    1981-01-01

    The use of laser Raman measurement techniques in remote sensing applications is surveyed. A feasibility index is defined as a means to characterize the practicality of a given remote Raman measurement application. Specific applications of Raman scattering to the measurement of atmospheric water vapor profiles, methane plumes from liquid natural gas spills, and subsurface ocean temperature profiles are described. This paper will survey the use of laser Raman measurement techniques in remote sensing applications using as examples specific systems that the Computer Genetics Corporation (CGC) group has developed and engineered.

  5. Effective Frequency Technique

    NASA Technical Reports Server (NTRS)

    Kirk, C. Laurence; Weng, Chi Y.

    2002-01-01

    An effective monochromatic frequency technique is described to represent the effects of finite spectral bandwidth for active and passive measurements centered on an absorption line, a trough region, or a slowly varying spectral feature. For Gaussian and rectangular laser line shapes, the effective frequency is shown to have a simple form which depends only on the instrumental line shape and bandwidth and not on the absorption line profile. The technique yields accuracies better than 0.1% for bandwidths less than 0.2 times the atmospheric line width.

  6. Craniospinal irradiation techniques

    SciTech Connect

    Scarlatescu, Ioana Avram, Calin N.; Virag, Vasile

    2015-12-07

    In this paper we present one treatment plan for irradiation cases which involve a complex technique with multiple beams, using the 3D conformational technique. As the main purpose of radiotherapy is to administrate a precise dose into the tumor volume and protect as much as possible all the healthy tissues around it, for a case diagnosed with a primitive neuro ectoderm tumor, we have developed a new treatment plan, by controlling one of the two adjacent fields used at spinal field, in a way that avoids the fields superposition. Therefore, the risk of overdose is reduced by eliminating the field divergence.

  7. Techniques for Vocal Health.

    ERIC Educational Resources Information Center

    Wiest, Lori

    1997-01-01

    Outlines a series of simple yet effective practices, techniques, and tips for improving the singing voice and minimizing stress on the vocal chords. Describes the four components for producing vocal sound: respiration, phonation, resonation, and articulation. Provides exercises for each and lists symptoms of sickness and vocal strain. (MJP)

  8. Merchandising Techniques and Libraries.

    ERIC Educational Resources Information Center

    Green, Sylvie A.

    1981-01-01

    Proposes that libraries employ modern booksellers' merchandising techniques to improve circulation of library materials. Using displays in various ways, the methods and reasons for weeding out books, replacing worn book jackets, and selecting new books are discussed. Suggestions for learning how to market and 11 references are provided. (RBF)

  9. Assessing Classroom Assessment Techniques

    ERIC Educational Resources Information Center

    Simpson-Beck, Victoria

    2011-01-01

    Classroom assessment techniques (CATs) are teaching strategies that provide formative assessments of student learning. It has been argued that the use of CATs enhances and improves student learning. Although the various types of CATs have been extensively documented and qualitatively studied, there appears to be little quantitative research…

  10. Multisensor Data Integration Techniques

    NASA Technical Reports Server (NTRS)

    Evans, D. L.; Blake, P. L.; Conel, J. E.; Lang, H. R.; Logan, T. L.; Mcguffie, B. A.; Paylor, E. D.; Singer, R. B.; Schenck, L. R.

    1985-01-01

    The availability of data from sensors operating in several different wavelength regions had led to the development of new techniques and strategies for both data management and image analysis. Work is ongoing to develop computer techniques for analysis of integrated data sets. These techniques include coregistration of multisensor images, rectification of radar images in areas of topographic relief to ensure pixel to pixel registration with planimetric data sets, calibration of data so that signatures can be applied to remote areas, normalization of data acquired with disparate sensors and determination of extended spectral signatures of surface units. In addition, software is being developed to analyze coregistrated digital terrain and image data so that automated stratigraphic and structural analyses can be performed. These software procedures include: strike and dip determination, terrain profile generation, stratigraphic column generation, stratigraphic thickness measurements, structural cross-section generation, and creation of 3-D block diagrams. These techniques were applied to coregistered LANDSAT 4 Thematic Mapper (TM), Thermal Infrared Multispectral Scanner (TIMS), and multipolarization synthetic aperture radar (SAR) data of the Wind River Basin in Wyoming.

  11. Blood Typing--Technique.

    ERIC Educational Resources Information Center

    Johnstone, W. T., Jr.

    This instructional packet deals with the study of hematology. It is recommended for all high school students of biology. A general understanding of antigen-antibody reactions is necessary before attempting this learning activity. Behavioral objectives place emphasis on the techniques of and understanding of blood typing. The equipment and…

  12. Super Techniques for Teachers.

    ERIC Educational Resources Information Center

    Foley, Michael K.

    A variety of techniques can help a teacher create the atmosphere of a "quality circle," a Japanese management method in which each member of a group shares and contributes to the learning experience. "Creating a Commercial" allows students to create original oratory for presentation to the class. In "The Good News First," students improve their…

  13. Study of coronagraphic techniques

    NASA Astrophysics Data System (ADS)

    Tolls, Volker; Aziz, Michael; Gonsalves, Robert A.; Korzennik, Sylvain; Labeyrie, Antoine; Lyon, Richard; Melnick, Gary; Schlitz, Ruth; Somerstein, Steve; Vasudevan, Gopal; Woodruff, Robert

    2006-06-01

    Smithsonian Astrophysical Observatory (SAO) has set up a program to study coronagraphic techniques. The program consists of the development of new fabrication methods of occulter masks, characterization of the manufactured masks, and application of the masks to study speckle reduction technique. Our occulter mask fabrication development utilizes a focused ion beam system to directly shape mask profiles from absorber material. Initial milling trials show that we can shape nearly Gaussian-shaped mask profiles. Part of this development is the characterization of absorber materials, poly(methyl methacrylate) doped with light-stable chromophores. For the characterization of the masks we have built a mask scanner enabling us to scan the transmission function of occulter masks. The real mask transmission profile is retrieved applying the maximum entropy method to deconvolve the mask transmission function from the beam profile of the test laser. Finally, our test bed for studying coronagraphic techniques is nearing completion. The optical setup is currently configured as a classical coronagraph and can easily be re-configured for studying speckle reduction techniques. The development of the test bed control software is under way. This paper we will give an update of the status of the individual program elements.

  14. Computational techniques in bioelectromagnetics

    NASA Astrophysics Data System (ADS)

    Iskander, Magdy F.

    1991-11-01

    Computer modeling and numerical techniques played an important role, found a wide variety of applications, and provided valuable results in the area of bioelectromagnetics. These techniques were used to calculate electromagnetic specific absorption rates (SARs) in various biological models, including humans, and to evaluate a wide variety of applicators used to administer microwave hyperthermia for cancer treatment both noninvasively and interstitially. Computational methods were also used to examine the feasibility of using microwaves in medical diagnosis and imaging. In these biomedical applications, both near- and far-field radiations were modeled and incident radiation from single and phased array antennas were utilized. In this paper, we review some of the computational techniques used in bioelectromagnetics. Example results are presented to illustrate the wide variety of applications involved in the area of bioelectromagnetics research. Advantages, limitations, and the complementary nature of three numerical techniques based on the method of moments, finite-difference time-domain, and the spherical-wave expansion methods are discussed. Tradeoffs involved in selecting a specific solution procedure to analyze the highly diverse applications in bioelectromagnetics are discussed and future needs in bioelectromagnetics research are briefly described.

  15. New Teaching Techniques.

    ERIC Educational Resources Information Center

    Health Education (Washington D.C.), 1985

    1985-01-01

    Health educators have consistently shown creativity in using innovative teaching techniques. Three articles from the past discuss "new" teaching methods: (1) "A Radio Project Teaches Your Class" (Miller); (2) "An Activity Program in Alcohol Education" (Breg); and (3) "Teaching Health Through Pictures" (Haviland). (CB)

  16. Art Appreciation and Technique.

    ERIC Educational Resources Information Center

    Dean, Diane R.; Milam, Debora

    1985-01-01

    Presents examples of independent study units for gifted high school students in a resource room setting. Both art appreciation and technique are covered in activities concerned with media (basics of pencil, India ink, pastels, crayons, oil, acrylics, and watercolors), subject matter (landscapes, animals, the human figure), design and illustration…

  17. Mathematical techniques: A compilation

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Articles on theoretical and applied mathematics are introduced. The articles cover information that might be of interest to workers in statistics and information theory, computational aids that could be used by scientists and engineers, and mathematical techniques for design and control.

  18. Techniques in Teaching Writing.

    ERIC Educational Resources Information Center

    Raimes, Ann

    A manual of techniques for teaching writing in classes of English as a second language (ESL) encourages composition beyond elementary-level sentence exercises. The objectives include communicating to a reader, expressing ideas without the pressure of face-to-face communication, exploring a subject, recording experiences, and becoming familiar with…

  19. Merchandising Techniques and Libraries.

    ERIC Educational Resources Information Center

    Green, Sylvie A.

    1981-01-01

    Proposes that libraries employ modern booksellers' merchandising techniques to improve circulation of library materials. Using displays in various ways, the methods and reasons for weeding out books, replacing worn book jackets, and selecting new books are discussed. Suggestions for learning how to market and 11 references are provided. (RBF)

  20. Techniques in Adlerian Psychology.

    ERIC Educational Resources Information Center

    Carlson, Jon, Ed.; Slavik, Steven, Ed.

    This book is a collection of classic and recent papers (published between 1964 and 1994) reprinted from the "Journal of Juvenile Psychology""Individual Psychologist," and "Individual Psychology." Each of the five sections is introduced by the editor's comments. "General Techniques" contains the following…

  1. Values Concepts and Techniques.

    ERIC Educational Resources Information Center

    National Education Association, Washington, DC.

    This book contains 29 articles for elementary and secondary teachers dealing with fundamental concepts and teaching techniques in values education. Part one of the book deals with concepts. Louis E. Raths examines valuing and its relationship to freedom and intelligence. The cognitive developmental approach to moral education is discussed by…

  2. RFI Mitigation / Excision techniques

    NASA Astrophysics Data System (ADS)

    Roshi, D. A.

    2004-06-01

    Radio frequency interference (RFI) is increasingly affecting radio astronomy research. A few years ago, active research to investigate the possibility of observing in the presence of interference using RFI mitigation techniques was initiated. In this paper, I briefly discuss four RFI mitigation/excision projects. These projects are:- (1) A technique to suppress double sideband amplitude modulated interference in which I show that an astronomical signal in the presence of a DSB interference can be observed with a signal-to-noise ratio factor of 2 less compared to observations if the RFI were not present. (2) Techniques to suppress interference due to synchronization signals in composite video signals are presented. A combination of noise-free modelling of the synchronization signals and adaptive filtering is used for suppressing the interference. (3) Design techniques to minimize spurious pick-up at the analog input of an analog-to-digital converter are discussed. (4) Spectral RFI excision using a spectral channel weighted scheme and its application to Green Bank telescope observations are also presented.

  3. Creative Job Search Technique

    ERIC Educational Resources Information Center

    Canadian Vocational Journal, 1974

    1974-01-01

    Creative Job Search Technique is based on the premise that most people have never learned how to systematically look for a job. A person who is unemployed can be helped to take a hard look at his acquired skills and relate those skills to an employer's needs. (Author)

  4. The Symbolic Identity Technique.

    ERIC Educational Resources Information Center

    Goud, Nelson H.

    2001-01-01

    Explains the role of symbols in attaining total psychic growth by applying concepts of C. Jung, R. Assagiolo, and L. Kubie. Describes a new strategy, the symbolic identity technique, which involves environmental exploration in a relaxed, receptive manner in order to discover something in the outer environment that reflects one's inner nature.…

  5. Techniques in Language Control.

    ERIC Educational Resources Information Center

    Richards, I. A.; Gibson, Christine

    This book attempts to introduce the reader to techniques of communication control, in listening and speaking as well as reading and writing. To this end, the use of a simplified vocabulary called Every Man's English is advocated. Section 2 presents some principles of Every Man's English. The contribution of Ogden's Basic English, a core vocabulary…

  6. Oral surgery. Basic techniques.

    PubMed

    Ross, D L; Goldstein, G S

    1986-09-01

    Some of the clinical problems most frequently seen in veterinary dentistry and their surgical solutions are discussed. Extraction of teeth, surgical repositioning of teeth, tooth transplant, oral abscesses of tooth origin, impaction of teeth, repair of maxillary canine oronasal fistula, and simple techniques for oral wiring are among the issues considered.

  7. Techniques in Adlerian Psychology.

    ERIC Educational Resources Information Center

    Carlson, Jon, Ed.; Slavik, Steven, Ed.

    This book is a collection of classic and recent papers (published between 1964 and 1994) reprinted from the "Journal of Juvenile Psychology""Individual Psychologist," and "Individual Psychology." Each of the five sections is introduced by the editor's comments. "General Techniques" contains the following…

  8. Super Techniques for Teachers.

    ERIC Educational Resources Information Center

    Foley, Michael K.

    A variety of techniques can help a teacher create the atmosphere of a "quality circle," a Japanese management method in which each member of a group shares and contributes to the learning experience. "Creating a Commercial" allows students to create original oratory for presentation to the class. In "The Good News First," students improve their…

  9. The attribute measurement technique

    SciTech Connect

    Macarthur, Duncan W; Langner, Diana; Smith, Morag; Thron, Jonathan; Razinkov, Sergey; Livke, Alexander

    2010-01-01

    Any verification measurement performed on potentially classified nuclear material must satisfy two seemingly contradictory constraints. First and foremost, no classified information can be released. At the same time, the monitoring party must have confidence in the veracity of the measurement. An information barrier (IB) is included in the measurement system to protect the potentially classified information while allowing sufficient information transfer to occur for the monitoring party to gain confidence that the material being measured is consistent with the host's declarations, concerning that material. The attribute measurement technique incorporates an IB and addresses both concerns by measuring several attributes of the nuclear material and displaying unclassified results through green (indicating that the material does possess the specified attribute) and red (indicating that the material does not possess the specified attribute) lights. The attribute measurement technique has been implemented in the AVNG, an attribute measuring system described in other presentations at this conference. In this presentation, we will discuss four techniques used in the AVNG: (1) the 1B, (2) the attribute measurement technique, (3) the use of open and secure modes to increase confidence in the displayed results, and (4) the joint design as a method for addressing both host and monitor needs.

  10. Correlative Techniques in Microscopy

    USDA-ARS?s Scientific Manuscript database

    Imaging is an important component in basic research, product development and understanding structure/function relationships in agricultural commodities and products. An array of microscopes and techniques can be used illustrate the structure and microchemistry of diverse samples. Examples of the var...

  11. Assessing Classroom Assessment Techniques

    ERIC Educational Resources Information Center

    Simpson-Beck, Victoria

    2011-01-01

    Classroom assessment techniques (CATs) are teaching strategies that provide formative assessments of student learning. It has been argued that the use of CATs enhances and improves student learning. Although the various types of CATs have been extensively documented and qualitatively studied, there appears to be little quantitative research…

  12. Problem Solving Techniques Seminar.

    ERIC Educational Resources Information Center

    Massachusetts Career Development Inst., Springfield.

    This booklet is one of six texts from a workplace literacy curriculum designed to assist learners in facing the increased demands of the workplace. Six problem-solving techniques are developed in the booklet to assist individuals and groups in making better decisions: problem identification, data gathering, data analysis, solution analysis,…

  13. Double-shell inertial confinement fusion target fabrication

    SciTech Connect

    Hatcher, C.W.; Lorensen, L.E.; Weinstein, B.W.

    1980-08-26

    First generation hemishells, from which spherical shells are constructed, were fabricated by micromachining coated mandrels and by molding. The remachining of coated mandrels are described in detail. Techniques were developed for coating the microsized mandrels with polymeric and metallic materials by methods including conformal coating, vapor deposition, plasma polymerization and thermoforming. Micropositioning equipment and bonding techniques have also been developed to assemble the hemishells about a fuel pellet maintaining a spherical concentricity of better than 2 ..mu..m and voids in the hemishell bonding line of a few hundred angstroms or less.

  14. New Etch Monitoring Technique

    NASA Astrophysics Data System (ADS)

    Kaiser, Christina; Adamcyk, Martin; Levy, Yuval; Tiedje, Tom; Young, Jeff F.; Kelson, Itzhak

    2000-05-01

    Plasma etching is an important tool for the development of various types of nanostructures. The development of specific plasma etching procedures is often time-consuming. We will describe an new technique for IN-SITU monitoring of the etch rate and sidewall profile of 1D GRATINGS in a remote plasma etcher. The technique involves monitoring the energy loss of alpha particles that propagate through the layer being etched. Samples to be etched are impregnated by a thin near-surface layer of 224Ra nuclei that decay by alpha particle emission. The energy spectrum of the alpha particles is acquired at intervals in the etch process. The etch rate on flat surfaces can be determined quite simply by measuring the change in the peak energy of the transmitted particles. By using a simple geometric model that employs the Bethe Bloch formula for energy loss of charges particles the etch profile of masked samples can also be inferred.

  15. Network acceleration techniques

    NASA Technical Reports Server (NTRS)

    Crowley, Patricia (Inventor); Awrach, James Michael (Inventor); Maccabe, Arthur Barney (Inventor)

    2012-01-01

    Splintered offloading techniques with receive batch processing are described for network acceleration. Such techniques offload specific functionality to a NIC while maintaining the bulk of the protocol processing in the host operating system ("OS"). The resulting protocol implementation allows the application to bypass the protocol processing of the received data. Such can be accomplished this by moving data from the NIC directly to the application through direct memory access ("DMA") and batch processing the receive headers in the host OS when the host OS is interrupted to perform other work. Batch processing receive headers allows the data path to be separated from the control path. Unlike operating system bypass, however, the operating system still fully manages the network resource and has relevant feedback about traffic and flows. Embodiments of the present disclosure can therefore address the challenges of networks with extreme bandwidth delay products (BWDP).

  16. Oberst beam test technique

    NASA Astrophysics Data System (ADS)

    Fasana, Alessandro; Garibaldi, Luigi; Giorcelli, Ermanno; Ruzzene, Massimo

    1998-06-01

    The definition of the mechanical properties of viscoelastic materials, i.e. the elastic modulus and the loss factor, is carried out, according to many national and international standards, with many different techniques, both of the resonant and non-resonant type. In this paper we focus our attention on the pros and cons of the resonant technique based on the classical Oberst beam method. When the damping material to be tested is not self-supporting, its properties are determined taking start from the measured modal frequencies and loss factors of a laminated beam, constituted by one or two metallic strips, ideally undamped, and one or two viscoelastic layers. The formulae specified on the standards hold valid under the assumptions of the theory developed by Kerwin, Ungar and Ross and we try in this paper to quantify witch deviation of the results should be expected when moving away from their ideal hypotheses.

  17. Nozzle fabrication technique

    NASA Technical Reports Server (NTRS)

    Wells, Dennis L. (Inventor)

    1988-01-01

    This invention relates to techniques for fabricating hour glass throat or convergent divergent nozzle shapes, and more particularly to new and improved techniques for forming rocket nozzles from electrically conductive material and forming cooling channels in the wall thereof. The concept of positioning a block of electrically conductive material so that its axis is set at a predetermined skew angle with relation to a travelling electron discharge machine electrode and thereafter revolving the body about its own axis to generate a hyperbolic surface of revolution, either internal or external is novel. The method will generate a rocket nozzle which may be provided with cooling channels using the same control and positioning system. The configuration of the cooling channels so produced are unique and novel. Also the method is adaptable to nonmetallic material using analogous cutting tools, such as, water jet, laser, abrasive wire and hot wire.

  18. [Molecular techniques in mycology].

    PubMed

    Rodríguez-Tudela, Juan Luis; Cuesta, Isabel; Gómez-López, Alicia; Alastruey-Izquierdo, Ana; Bernal-Martínez, Leticia; Cuenca-Estrella, Manuel

    2008-11-01

    An increasing number of molecular techniques for the diagnosis of fungal infections have been developed in the last few years, due to the growing prevalence of mycoses and the length of time required for diagnosis when classical microbiological methods are used. These methods are designed to resolve the following aspects of mycological diagnosis: a) Identification of fungi to species level by means of sequencing relevant taxonomic targets; b) early clinical diagnosis of invasive fungal infections; c) detection of molecular mechanisms of resistance to antifungal agents; and d) molecular typing of fungi. Currently, these methods are restricted to highly developed laboratories. However, some of these techniques will probably be available in daily clinical practice in the near future.

  19. Instrument techniques for rheometry

    NASA Astrophysics Data System (ADS)

    Hou, Ying Y.; Kassim, Hamida O.

    2005-10-01

    This article presents a review of some latest advances in rheology measuring techniques. Consideration is given to the modification and approaches in conventional measuring techniques and also to the development of specialty instruments. A number of sensing technologies such as nuclear-magnetic-resonance imaging and ultrasonic pulse Doppler mapping have recently been adopted to produce viscoelastic measurements for both Newtonian and non-Newtonian materials. The working principles of these technologies and their applications are described. Other recent developments in modifications of conventional rheometers for performance enhancement and for complex material characterizations have been thoroughly discussed. Some instrument designs and their special applications, such as interfacial rheometers, extensional rheometers, and high-pressure rheometers, have also been evaluated in detail.

  20. CTV rendezvous techniques

    NASA Astrophysics Data System (ADS)

    Jennings, Jerry L.; Anderson, Robert L.

    The cargo transfer vehicle (CTV) requires the capability to perform automated rendezvous with Space Station Freedom (SSF) using onboard sensors and algorithms. The current approach to CTV rendezvous applies techniques developed during the orbital maneuvering vehicle (OMV) program which have been mechanized for automatic, onboard execution. The initial catch up sequence can be described as a passive rendezvous without explicit time of arrival control. The ultimate requirement for this rendezvous technique is to place the CTV on the SSF V-bar axis at some specified downrange distance. The launch vehicle will use yaw steering during orbit injection to achieve the proper phantom plane for nodal biasing. This presentation describes the primary components of the CTV rendezvous scheme.

  1. CTV rendezvous techniques

    NASA Technical Reports Server (NTRS)

    Jennings, Jerry L.; Anderson, Robert L.

    1991-01-01

    The cargo transfer vehicle (CTV) requires the capability to perform automated rendezvous with Space Station Freedom (SSF) using onboard sensors and algorithms. The current approach to CTV rendezvous applies techniques developed during the orbital maneuvering vehicle (OMV) program which have been mechanized for automatic, onboard execution. The initial catch up sequence can be described as a passive rendezvous without explicit time of arrival control. The ultimate requirement for this rendezvous technique is to place the CTV on the SSF V-bar axis at some specified downrange distance. The launch vehicle will use yaw steering during orbit injection to achieve the proper phantom plane for nodal biasing. This presentation describes the primary components of the CTV rendezvous scheme.

  2. Whole cell entrapment techniques.

    PubMed

    Trelles, Jorge A; Rivero, Cintia W

    2013-01-01

    Microbial whole cells are efficient, ecological, and low-cost catalysts that have been successfully applied in the pharmaceutical, environmental, and alimentary industries, among others. Microorganism immobilization is a good way to carry out the bioprocess under preparative conditions. The main advantages of this methodology lie in their high operational stability, easy upstream separation and bioprocess scale-up feasibility. Cell entrapment is the most widely used technique for whole cell immobilization. This technique-in which the cells are included within a rigid network-is porous enough to allow the diffusion of substrates and products, protects the selected microorganism from the reaction medium, and has high immobilization efficiency (100 % in most cases).

  3. Data collection techniques.

    PubMed

    Morgan, G A; Harmon, R J

    2001-08-01

    We have provided an overview of techniques used to assess variables in the applied behavioral sciences. Most of the methods are used by both quantitative/positivist and qualitative/constructivist researchers but to different extents. Qualitative researchers prefer more open-ended, less structured data collection techniques than do quantitative researchers. Direct observation of participants is common in experimental and qualitative research; it is less common in so-called survey research, which tends to use self-report questionnaires. It is important that investigators use instruments that are reliable and valid for the population and purpose for which they will be used. Standardized instruments have manuals that provide norms and indexes of reliability and validity. However, if the populations and purpose on which these data are based are different from yours, it may be necessary for you to develop your own instrument or provide new evidence of reliability and validity.

  4. Brain Vascular Imaging Techniques

    PubMed Central

    Laviña, Bàrbara

    2016-01-01

    Recent major improvements in a number of imaging techniques now allow for the study of the brain in ways that could not be considered previously. Researchers today have well-developed tools to specifically examine the dynamic nature of the blood vessels in the brain during development and adulthood; as well as to observe the vascular responses in disease situations in vivo. This review offers a concise summary and brief historical reference of different imaging techniques and how these tools can be applied to study the brain vasculature and the blood-brain barrier integrity in both healthy and disease states. Moreover, it offers an overview on available transgenic animal models to study vascular biology and a description of useful online brain atlases. PMID:28042833

  5. Novel Diffusivity Measurement Technique

    NASA Technical Reports Server (NTRS)

    Rashidnia, Nasser

    2001-01-01

    A common-path interferometer (CPI) system was developed to measure the diffusivity of liquid pairs. The CPI is an optical technique that can be used to measure changes in the gradient of the refraction index of transparent materials. This system uses a shearing interferometer that shares the same optical path from a laser light source to the final imaging plane. Hence, the molecular diffusion coefficient of liquids can be determined using the physical relations between changes in the optical path length and the liquid phase properties. The data obtained with this interferometer were compared with similar results from other techniques and demonstrated that the instrument is superior in measuring the diffusivity of miscible liquids while keeping the system very compact and robust. CPI can also be used for studies in interface dynamics and other diffusion-dominated-process applications.

  6. Particle-mesh techniques

    NASA Technical Reports Server (NTRS)

    Macneice, Peter

    1995-01-01

    This is an introduction to numerical Particle-Mesh techniques, which are commonly used to model plasmas, gravitational N-body systems, and both compressible and incompressible fluids. The theory behind this approach is presented, and its practical implementation, both for serial and parallel machines, is discussed. This document is based on a four-hour lecture course presented by the author at the NASA Summer School for High Performance Computational Physics, held at Goddard Space Flight Center.

  7. Colorimetric protein assay techniques.

    PubMed

    Sapan, C V; Lundblad, R L; Price, N C

    1999-04-01

    There has been an increase in the number of colorimetric assay techniques for the determination of protein concentration over the past 20 years. This has resulted in a perceived increase in sensitivity and accuracy with the advent of new techniques. The present review considers these advances with emphasis on the potential use of such technologies in the assay of biopharmaceuticals. The techniques reviewed include Coomassie Blue G-250 dye binding (the Bradford assay), the Lowry assay, the bicinchoninic acid assay and the biuret assay. It is shown that each assay has advantages and disadvantages relative to sensitivity, ease of performance, acceptance in the literature, accuracy and reproducibility/coefficient of variation/laboratory-to-laboratory variation. A comparison of the use of several assays with the same sample population is presented. It is suggested that the most critical issue in the use of a chromogenic protein assay for the characterization of a biopharmaceutical is the selection of a standard for the calibration of the assay; it is crucial that the standard be representative of the sample. If it is not possible to match the standard with the sample from the perspective of protein composition, then it is preferable to use an assay that is not sensitive to the composition of the protein such as a micro-Kjeldahl technique, quantitative amino acid analysis or the biuret assay. In a complex mixture it might be inappropriate to focus on a general method of protein determination and much more informative to use specific methods relating to the protein(s) of particular interest, using either specific assays or antibody-based methods. The key point is that whatever method is adopted as the 'gold standard' for a given protein, this method needs to be used routinely for calibration.

  8. Electronic Packaging Techniques

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A characteristic of aerospace system design is that equipment size and weight must always be kept to a minimum, even in small components such as electronic packages. The dictates of spacecraft design have spawned a number of high-density packaging techniques, among them methods of connecting circuits in printed wiring boards by processes called stitchbond welding and parallel gap welding. These processes help designers compress more components into less space; they also afford weight savings and lower production costs.

  9. Numerical Techniques in Acoustics

    NASA Technical Reports Server (NTRS)

    Baumeister, K. J. (Compiler)

    1985-01-01

    This is the compilation of abstracts of the Numerical Techniques in Acoustics Forum held at the ASME's Winter Annual Meeting. This forum was for informal presentation and information exchange of ongoing acoustic work in finite elements, finite difference, boundary elements and other numerical approaches. As part of this forum, it was intended to allow the participants time to raise questions on unresolved problems and to generate discussions on possible approaches and methods of solution.

  10. Resin infiltration transfer technique

    DOEpatents

    Miller, David V.; Baranwal, Rita

    2009-12-08

    A process has been developed for fabricating composite structures using either reaction forming or polymer infiltration and pyrolysis techniques to densify the composite matrix. The matrix and reinforcement materials of choice can include, but are not limited to, silicon carbide (SiC) and zirconium carbide (ZrC). The novel process can be used to fabricate complex, net-shape or near-net shape, high-quality ceramic composites with a crack-free matrix.

  11. Materials Coating Techniques

    DTIC Science & Technology

    1980-03-01

    properties of the coating layers and their interaction with the bulk material will be considered. Lectures will also cover the behaviour of coated parts...stability etc. Finally, available techniques for the analysis and non-destructive evaluation of the composition. properties and soundness of the...provide stiffness or flexibility, and to carry the applied loads without macroscopic failure. Such properties are associated with the bulk material of

  12. Diagnostic techniques for dermatophytosis.

    PubMed

    Moriello, K A

    2001-11-01

    This article reviews the use of common diagnostic tools for the identification and isolation of dermatophyte infections in small animals. The use of the Wood's lamp as a screening tool is discussed, along with its usefulness as an aid in the microscopic examination of hairs for fungal elements. Tests for the definitive diagnosis of dermatophytosis are highlighted and include: direct examination of hair for ectothrix spores, fungal cultures, and skin biopsy. Sampling techniques, procedures, and interpretation of test results are also detailed.

  13. Advancement on Visualization Techniques

    DTIC Science & Technology

    1980-10-01

    Aeroa and As ronautics Massachusetts Institute of Technology Cambridge, MA 02139 USA I !ii 1 I This AGARDograph was prepared at the request of the...the fields of science § and technology relating to aerospace for the following purposes: - Exchanging of scientific and technical information...Techniques for providing the pilot visualization have grown rapidly. Technology has developed fron mechanical gauges through electro-mechanical

  14. The Plate Overlap Technique.

    DTIC Science & Technology

    1978-07-31

    INTRODUCTION 1 II. NOTATION 2 III. THE GNOMONIC PROJECTION 4 IV . THE PLATE OVERLAP TECHNIQUE 6 A. MOTIVATION 6 B. FORNULATION 9 C. ON STATISTICAL RIGOR 14 D...and new hardware. Since this aim was clearly recognized long ago, wherever possible in earlier documents or software development flexibility was...reader should see 1, 2, and 3. The procedures one should use to update stellar positions are discussed in 4 with applica- tions to the SAOC in 5. Non

  15. Weld braze technique

    DOEpatents

    Kanne, Jr., William R.; Kelker, Jr., John W.; Alexander, Robert J.

    1982-01-01

    High-strength metal joints are formed by a combined weld-braze technique. A hollow cylindrical metal member is forced into an undersized counterbore in another metal member with a suitable braze metal disposed along the bottom of the counterbore. Force and current applied to the members in an evacuated chamber results in the concurrent formation of the weld along the sides of the counterbore and a braze along the bottom of the counterbore in one continuous operation.

  16. Synthetic battery cycling techniques

    NASA Technical Reports Server (NTRS)

    Leibecki, H.; Thaller, L. H.

    1982-01-01

    The group of techniques that as a class are referred to as synthetic battery cycling are described with reference to spacecraft battery systems. Synthetic battery cycling makes use of the capability of computer graphics to illustrate some of the basic characteristics of operation of individual electrodes within an operating electrochemical cell. It can also simulate the operation of an entire string of cells that are used as the energy storage subsystem of a power system.

  17. Forming techniques and procedures

    NASA Astrophysics Data System (ADS)

    Ronde-Oustau, F.

    1980-09-01

    Several forming techniques are discussed including: (1) cooling stamping and swaging tools by the "Caloduc' methods; (2) non-burr stamping (stamping in a closed die); (3) continuous casting; (4) orbital forging; and (5) plastic deformation and spheroidal graphite iron. In addition, the subject of superplasticity is discussed in some detail, and brief consideration is given to precision forging, forging die castings, sintered forging, squeeze casting, ausforming, magnetoforming, and ultrasonic forming.

  18. Emerging technology and techniques.

    PubMed

    Chander, Gopi Naveen; Mutukumar, B; Sasikala, C; Dhanasekar, N

    2015-01-01

    A technique of fabricating feldspathic porcelain pressable ingots was proposed. A 5 ml disposable syringe was used to condense the powder slurry. The condensed porcelain was sintered at 900΀C to produce porcelain ingots. The fabricated porcelain ingots were used in pressable ceramic machines. The technological advantages of pressable system improve the properties, and the fabricated ingot enhances the application of feldspathic porcelain.

  19. Endovascular extraction techniques

    PubMed Central

    Bracke, F.A.; Meijer, A.; van Gelder, B.

    2001-01-01

    The use of lead extraction is expanding with the introduction of new endovascular extraction techniques. Indications for extraction of chronically implanted pacemaker leads have been classified as mandatory, necessary or discretionary, but their rationale is often based on clinical judgement without corresponding support from the literature. We reviewed the literature of pacemaker lead-related complications as a starting point for discussing the indications for lead extraction. ImagesFigure 1Figure 2Figure 3 PMID:25696699

  20. Endoscopic ultrasound hemostasis techniques.

    PubMed

    Artifon, Everson L A; Aparicio, Dayse P S; Otoch, Jose P; Carvalho, Paulo B; Marson, Fernando P; Fernandes, Kaie; Tchekmedyian, Asadur J

    2014-04-01

    Since its development, endoscopic ultrasound (EUS) has evolved from a simple diagnostic technique to an important therapeutic tool for interventional endoscopy. EUS analysis provides real-time imaging of most major thoracic and abdominal vessels, and the possibility to use needle puncture with a curved linear array echoendoscope as a vascular intervention. In this review, we describe the endoscopic ultrasound approach to vascular therapy outside of the gastrointestinal wall.

  1. Synthetic battery cycling techniques

    SciTech Connect

    Leibecki, H.; Thaller, L.H.

    1982-09-01

    The group of techniques that as a class are referred to as synthetic battery cycling are described with reference to spacecraft battery systems. Synthetic battery cycling makes use of the capability of computer graphics to illustrate some of the basic characteristics of operation of individual electrodes within an operating electrochemical cell. It can also simulate the operation of an entire string of cells that are used as the energy storage subsystem of a power system.

  2. Advanced echocardiographic techniques

    PubMed Central

    Perry, Rebecca

    2015-01-01

    Abstract Echocardiography has advanced significantly since its first clinical use. The move towards more accurate imaging and quantification has driven this advancement. In this review, we will briefly focus on three distinct but important recent advances, three‐dimensional (3D) echocardiography, contrast echocardiography and myocardial tissue imaging. The basic principles of these techniques will be discussed as well as current and future clinical applications. PMID:28191159

  3. Dynamic Environmental Qualification Techniques

    DTIC Science & Technology

    1979-11-01

    ORGANISATION DU TRAITE DE L’ATLANTIQUE NORD) AGARD Report No.682 DYNAMIC ENVIRONMENTAL QUALIFICATION TECHNIQUES II¥ ,n . r-,, q - .j, i ~Papers present d at...better the knowledge of sources of excitation, transmission paths, dynamic system behaviour , the better the understanding and establishment of appropriate...featuring resonance dwell have poor similarity to the dynamic equipment behaviour in the A/C. As a specific example, a vibration test with a

  4. Image compression technique

    DOEpatents

    Fu, C.Y.; Petrich, L.I.

    1997-03-25

    An image is compressed by identifying edge pixels of the image; creating a filled edge array of pixels each of the pixels in the filled edge array which corresponds to an edge pixel having a value equal to the value of a pixel of the image array selected in response to the edge pixel, and each of the pixels in the filled edge array which does not correspond to an edge pixel having a value which is a weighted average of the values of surrounding pixels in the filled edge array which do correspond to edge pixels; and subtracting the filled edge array from the image array to create a difference array. The edge file and the difference array are then separately compressed and transmitted or stored. The original image is later reconstructed by creating a preliminary array in response to the received edge file, and adding the preliminary array to the received difference array. Filling is accomplished by solving Laplace`s equation using a multi-grid technique. Contour and difference file coding techniques also are described. The techniques can be used in a method for processing a plurality of images by selecting a respective compression approach for each image, compressing each of the images according to the compression approach selected, and transmitting each of the images as compressed, in correspondence with an indication of the approach selected for the image. 16 figs.

  5. Scalp imaging techniques

    NASA Astrophysics Data System (ADS)

    Otberg, Nina; Shapiro, Jerry; Lui, Harvey; Wu, Wen-Yu; Alzolibani, Abdullateef; Kang, Hoon; Richter, Heike; Lademann, Jürgen

    2017-05-01

    Scalp imaging techniques are necessary tools for the trichological practice and for visualization of permeation, penetration and absorption processes into and through the scalp and for the research on drug delivery and toxicology. The present letter reviews different scalp imaging techniques and discusses their utility. Moreover, two different studies on scalp imaging techniques are presented in this letter: (1) scalp imaging with phototrichograms in combination with laser scanning microscopy, and (2) follicular measurements with cyanoacrylate surface replicas and light microscopy in combination with laser scanning microscopy. The experiments compare different methods for the determination of hair density on the scalp and different follicular measures. An average terminal hair density of 132 hairs cm-2 was found in 6 Caucasian volunteers and 135 hairs cm-2 in 6 Asian volunteers. The area of the follicular orifices accounts to 16.3% of the skin surface on average measured with laser scanning microscopy images. The potential volume of the follicular infundibulum was calculated based on the laser scanning measurements and is found to be 4.63 mm3 per cm2 skin on average. The experiments show that hair follicles are quantitatively relevant pathways and potential reservoirs for topically applied drugs and cosmetics.

  6. Conchomeatoplasty: a new technique.

    PubMed

    Giacomarra, Vittorio; Spinato, Giacomo; Bullo, Federica; Da Mosto, Maria Cristina; Boscolo-Rizzo, Paolo; Tirelli, Giancarlo; Tirelli, Gianfranco

    2013-11-01

    Stenosis of the cartilaginous auditory canal is still difficult to resolve and many techniques of plastic surgery have been proposed. Our experience was first built up in treatment of stenosis of the tracheostomy in patients who had undergone laryngectomy. Since it is simple and effective, we have transferred and modified the technique to the treatment of stenosis of the external auditory canal and of the concha. Fourteen patients with stenosis of the cartilaginous auditory canal (diameters of the stenosis prior to surgery varied from 19 to 78.5 mm(2)) underwent day-surgery conchomeatoplasty under local anaesthesia. Eight months after the operation, the results are good. Following surgery, the surface of the auditory canal, measured at the narrowest point of the external auditory meatus, varied from a minimum of 113 mm(2) to a maximum of 254 mm(2). The technique we propose to correct the stenosis of the external auditory canal is easy to carry out, short, and may be performed under local anaesthesia. Lastly, the auditory canal and the ear auricle have a good blood supply, thus ensuring the flaps will survive.

  7. Safe monsplasty technique.

    PubMed

    Patoué, Audrey; De Runz, Antoine; Carloni, Raphael; Aillet, Sylvie; Watier, Eric; Bertheuil, Nicolas

    2017-07-14

    To improve their health and quality of life, obese patients undergo consultation after weight loss. In these patients, the sub-umbilical abdominal and pubic regions are often characterized by redundant skin, creating aesthetic and functional discomfort. Monsplasty is an important step in abdominoplasty or bodylift procedures. We report on an original technique used to correct deformity in the pubic region following weight loss. All interventions were performed by the same surgeon between April and December 2015. On stretched skin, we drew two lines 5 cm lateral to the median line on both sides and connected them with the arc of a circle placed 7 cm from the vulvar fork. Then, monsplasty marks extend to abdominal fold. During lower abdominal contouring, we performed monsplasty with three separate stitches between the camper fascia and aponeurosis of the abdominal muscle. The aim was to bring tension to the pubic region without additional surgical procedure. We report on 21 consecutive cases of monsplasty following lower trunk contouring. No reoperation was performed due to complication or aesthetic demand (no under- or over-correction occurred). No complication (e.g. edema, seroma, disturbance of sensibility) was observed in the pubic area. The results were stable 1 year after surgery. We report on a simple, rapid, and reproducible monsplasty technique for all stages of Pittsburgh classifications, which achieved favorable results with no complication. We recommend performance of this effective technique simultaneously with abdominoplasty or bodylift procedures. IV.

  8. Image compression technique

    DOEpatents

    Fu, Chi-Yung; Petrich, Loren I.

    1997-01-01

    An image is compressed by identifying edge pixels of the image; creating a filled edge array of pixels each of the pixels in the filled edge array which corresponds to an edge pixel having a value equal to the value of a pixel of the image array selected in response to the edge pixel, and each of the pixels in the filled edge array which does not correspond to an edge pixel having a value which is a weighted average of the values of surrounding pixels in the filled edge array which do correspond to edge pixels; and subtracting the filled edge array from the image array to create a difference array. The edge file and the difference array are then separately compressed and transmitted or stored. The original image is later reconstructed by creating a preliminary array in response to the received edge file, and adding the preliminary array to the received difference array. Filling is accomplished by solving Laplace's equation using a multi-grid technique. Contour and difference file coding techniques also are described. The techniques can be used in a method for processing a plurality of images by selecting a respective compression approach for each image, compressing each of the images according to the compression approach selected, and transmitting each of the images as compressed, in correspondence with an indication of the approach selected for the image.

  9. [Progress in imaging techniques].

    PubMed

    Mishima, Kazuaki; Otsuka, Tsukasa

    2013-05-01

    Today it is common to perform real-time diagnosis and treatment via live broadcast as a method of education and to spread new technology for diagnosis and therapy in medical fields. Live medical broadcasts have developed along with broadcast technology. In the early days, live video feeds were sent from operating rooms to classrooms and lecture halls in universities and hospitals. However, the development of imaging techniques and communication networks enabled live broadcasts that bi-directionally link operating rooms and meeting halls during scientific meetings and live demonstration courses. Live broadcasts therefore became an important method for education and the dissemination of new medical technologies. The development of imaging techniques has contributed to more realistic live broadcasts through such innovative techniques as three-dimensional viewing and higher-definition 4K technology. In the future, live broadcasts will be transmitted on personal computers using regular Internet connections. In addition to the enhancement of image delivery technology, it will also be necessary to examine the entire image delivery environment carefully, including issues of security and privacy of personal information.

  10. Covariance mapping techniques

    NASA Astrophysics Data System (ADS)

    Frasinski, Leszek J.

    2016-08-01

    Recent technological advances in the generation of intense femtosecond pulses have made covariance mapping an attractive analytical technique. The laser pulses available are so intense that often thousands of ionisation and Coulomb explosion events will occur within each pulse. To understand the physics of these processes the photoelectrons and photoions need to be correlated, and covariance mapping is well suited for operating at the high counting rates of these laser sources. Partial covariance is particularly useful in experiments with x-ray free electron lasers, because it is capable of suppressing pulse fluctuation effects. A variety of covariance mapping methods is described: simple, partial (single- and multi-parameter), sliced, contingent and multi-dimensional. The relationship to coincidence techniques is discussed. Covariance mapping has been used in many areas of science and technology: inner-shell excitation and Auger decay, multiphoton and multielectron ionisation, time-of-flight and angle-resolved spectrometry, infrared spectroscopy, nuclear magnetic resonance imaging, stimulated Raman scattering, directional gamma ray sensing, welding diagnostics and brain connectivity studies (connectomics). This review gives practical advice for implementing the technique and interpreting the results, including its limitations and instrumental constraints. It also summarises recent theoretical studies, highlights unsolved problems and outlines a personal view on the most promising research directions.

  11. Applied ALARA techniques

    SciTech Connect

    Waggoner, L.O.

    1998-02-05

    The presentation focuses on some of the time-proven and new technologies being used to accomplish radiological work. These techniques can be applied at nuclear facilities to reduce radiation doses and protect the environment. The last reactor plants and processing facilities were shutdown and Hanford was given a new mission to put the facilities in a safe condition, decontaminate, and prepare them for decommissioning. The skills that were necessary to operate these facilities were different than the skills needed today to clean up Hanford. Workers were not familiar with many of the tools, equipment, and materials needed to accomplish:the new mission, which includes clean up of contaminated areas in and around all the facilities, recovery of reactor fuel from spent fuel pools, and the removal of millions of gallons of highly radioactive waste from 177 underground tanks. In addition, this work has to be done with a reduced number of workers and a smaller budget. At Hanford, facilities contain a myriad of radioactive isotopes that are 2048 located inside plant systems, underground tanks, and the soil. As cleanup work at Hanford began, it became obvious early that in order to get workers to apply ALARA and use hew tools and equipment to accomplish the radiological work it was necessary to plan the work in advance and get radiological control and/or ALARA committee personnel involved early in the planning process. Emphasis was placed on applying,ALARA techniques to reduce dose, limit contamination spread and minimize the amount of radioactive waste generated. Progress on the cleanup has,b6en steady and Hanford workers have learned to use different types of engineered controls and ALARA techniques to perform radiological work. The purpose of this presentation is to share the lessons learned on how Hanford is accomplishing radiological work.

  12. Multimodality imaging techniques.

    PubMed

    Martí-Bonmatí, Luis; Sopena, Ramón; Bartumeus, Paula; Sopena, Pablo

    2010-01-01

    In multimodality imaging, the need to combine morphofunctional information can be approached by either acquiring images at different times (asynchronous), and fused them through digital image manipulation techniques or simultaneously acquiring images (synchronous) and merging them automatically. The asynchronous post-processing solution presents various constraints, mainly conditioned by the different positioning of the patient in the two scans acquired at different times in separated machines. The best solution to achieve consistency in time and space is obtained by the synchronous image acquisition. There are many multimodal technologies in molecular imaging. In this review we will focus on those multimodality image techniques more commonly used in the field of diagnostic imaging (SPECT-CT, PET-CT) and new developments (as PET-MR). The technological innovations and development of new tracers and smart probes are the main key points that will condition multimodality image and diagnostic imaging professionals' future. Although SPECT-CT and PET-CT are standard in most clinical scenarios, MR imaging has some advantages, providing excellent soft-tissue contrast and multidimensional functional, structural and morphological information. The next frontier is to develop efficient detectors and electronics systems capable of detecting two modality signals at the same time. Not only PET-MR but also MR-US or optic-PET will be introduced in clinical scenarios. Even more, MR diffusion-weighted, pharmacokinetic imaging, spectroscopy or functional BOLD imaging will merge with PET tracers to further increase molecular imaging as a relevant medical discipline. Multimodality imaging techniques will play a leading role in relevant clinical applications. The development of new diagnostic imaging research areas, mainly in the field of oncology, cardiology and neuropsychiatry, will impact the way medicine is performed today. Both clinical and experimental multimodality studies, in

  13. RFI emitter location techniques

    NASA Technical Reports Server (NTRS)

    Rao, B. L. J.

    1973-01-01

    The possibility is discussed of using Doppler techniques for determining the location of ground based emitters causing radio frequency interference with low orbiting satellites. An error analysis indicates that it is possible to find the emitter location within an error range of 2 n.mi. The parameters which determine the required satellite receiver characteristic are discussed briefly along with the non-real time signal processing which may by used in obtaining the Doppler curve. Finally, the required characteristics of the satellite antenna are analyzed.

  14. Formulation techniques for nanofluids.

    PubMed

    Rivera-Solorio, Carlos I; Payán-Rodríguez, Luis A; García-Cuéllar, Alejandro J; Ramón-Raygoza, E D; L Cadena-de-la-Peña, Natalia; Medina-Carreón, David

    2013-11-01

    Fluids with suspended nanoparticles, commonly known as nanofluids, may be formulated to improve the thermal performance of industrial heat transfer systems and applications. Nanofluids may show enhanced thermal and electrical properties such as thermal conductivity, viscosity, heat transfer coefficient, dielectric strength, etc. However, stability problems may arise as nanoparticles usually have the tendency to agglomerate and sediment producing deterioration in the increment of these properties. In this review, we discuss patents that report advances in the formulation of nanofluids including: production methods, selection of components (nanoparticles, base fluid and surfactants), their chemical compositions and morphologies, and characterization techniques. Finally, current and future directions in the development of nanofluid formulation are discussed.

  15. Monovision techniques for telerobots

    SciTech Connect

    Goode, P.W.; Cornils, K.

    1987-01-01

    The primary task of the vision sensor in a telerobotic system is to provide information about the position of the system's effector relative to objects of interest in its environment. The subtasks required to perform the primary task include image segmentation, object recognition, and object location and orientation in some coordinate system. The accomplishment of the vision task requires the appropriate processing tools and the system methodology to effectively apply the tools to the subtasks. This paper describes the functional structure of the telerobotic vision system used in the Langley Research Center's (LaRC) Intelligent Systems Research Laboratory (ISRL) and discusses two monovision techniques for accomplishing the vision subtasks. 11 references.

  16. Optical Techniques in Optogenetics

    PubMed Central

    Mohanty, Samarendra K.; Lakshminarayananan, Vasudevan

    2015-01-01

    Optogenetics is an innovative technique for optical control of cells. This field has exploded over the past decade or so and has given rise to great advances in neuroscience. A variety of applications both from the basic and applied research have emerged, turning the early ideas into a powerful paradigm for cell biology, neuroscience and medical research. This review aims at highlighting the basic concepts that are essential for a comprehensive understanding of optogenetics and some important biological/biomedical applications. Further, emphasis is placed on advancement in optogenetics-associated light-based methods for controlling gene expression, spatially-controlled optogenetic stimulation and detection of cellular activities. PMID:26412943

  17. Western Blot Techniques.

    PubMed

    Kim, Brianna

    2017-01-01

    The Western blot is an important laboratory technique that allows for specific identification and characterization of proteins. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)-separated proteins are electophoretically transferred to a polyvinylidene fluoride (PVDF) membrane which is then incubated with specific antibodies, then developed to show the protein of interest. Here, we describe the transfer and detection of Outer surface protein A (OspA), a protein only found on the surface of Borrelia burgdorferi, the bacteria responsible for Lyme disease.

  18. SAR antenna calibration techniques

    NASA Technical Reports Server (NTRS)

    Carver, K. R.; Newell, A. C.

    1978-01-01

    Calibration of SAR antennas requires a measurement of gain, elevation and azimuth pattern shape, boresight error, cross-polarization levels, and phase vs. angle and frequency. For spaceborne SAR antennas of SEASAT size operating at C-band or higher, some of these measurements can become extremely difficult using conventional far-field antenna test ranges. Near-field scanning techniques offer an alternative approach and for C-band or X-band SARs, give much improved accuracy and precision as compared to that obtainable with a far-field approach.

  19. Automatic Threshold Detector Techniques

    DTIC Science & Technology

    1976-07-15

    TECHNIQUES Contract No. DAAH01-76-C-0363 ER76-4208 15 July 1976 Prepared for: HEADQUA RTERS U.S. Army Missile Command Redstone Arsenal, Alabama 35809 j...rain cross section each FFT filter) a MUT, MUCL , KCL, MUN, MUCLF (2 ), MUl, MUWI= MUW2 where MUT = Target cross section (M2), MUCL = total ground...variable is currently not used by the program. Since there is yet no point clutter model, MUCL represents the fluctuating component. Until a point plus

  20. Interviewing techniques: an overview.

    PubMed

    Estrada, Jack

    2009-01-01

    Taking the correct precautions, being well prepared, doing the research, and reassessing the real needs when vacancies arise will assure success in hiring the best candidate for the job(s). Job descriptions, interviewing technique, communication style,and candidate evaluations are discussed as foundations for hiring successfully. Hiring managers should trust their own instincts if they have had previous success with hiring high performance employees. Often times it will come down to making a decision using best judgment based on the facts that have been gathered through the interview process.

  1. Intelligent Tracking Techniques

    DTIC Science & Technology

    1979-09-30

    11x6 + 12x9 + 13x9 + ]. = 17.78 and,156"’ Y = YBAR = 1-’[6x6 + 7x4 + 8x12 + 9x14 + ... ] 1888/156 12.10. The variances, S( 2 = I n n tu’ a • J - (XBAR)l...8217~~5. TYPE Of REPORT a PERIOD COVERED InelgntTakn Techniques i/ Fourth Quarterly Report Y -Report-July 1, 1979 - Sept. 30, 1979 .-ERFRMIN ORO...equipment which reduces its effectiveness. Effectiveness must be maintained in spite of enem~ y tactics encountered during an attack. One tactic which

  2. Synthetic battery cycling techniques

    SciTech Connect

    Leibecki, H.F.; Thaller, L.H.

    1982-01-01

    Synthetic battery cycling makes use of the fast growing capability of computer graphics to illustrate some of the basic characteristics of operation of individual electrodes within an operating electrochemical cell. It can also simulate the operation of an entire string of cells that are used as the energy storage subsystem of a power system. The group of techniques that as a class have been referred to as Synthetic Battery Cycling is developed in part to try to bridge the gap of understanding that exists between single cell characteristics and battery system behavior.

  3. Percutaneous nephrolithotomy: technique.

    PubMed

    Knoll, Thomas; Daels, Francisco; Desai, Janak; Hoznek, Andras; Knudsen, Bodo; Montanari, Emanuele; Scoffone, Cesare; Skolarikos, Andreas; Tozawa, Keiichi

    2017-01-25

    Percutaneous nephrolithotomy (PCNL) is considered to be the first line of treatment for large renal stones. Though PCNL comes with higher morbidity, its efficacy is unbeaten by other minimally invasive modalities. However, potential complications, such as bleeding, occur. Improved skills and modifications of the procedure may reduce the probability of adverse outcomes. This article discusses the current trends and standards in PCNL technique with special focus on all important steps as positioning, access, instruments, dilation, disintegration, and exit, including outcomes, complication management, and training modalities.

  4. ECM techniques generator

    NASA Astrophysics Data System (ADS)

    Nunez, Abel S.; Marshall, Patrick T.; McGrath, Michael; Byers, Christopher D.; Simpson, Chad; Hong, Seng M.

    2006-05-01

    The development of electronic countermeasures against target track radars is both an expensive and time-consuming process. One method of cutting development time is to use genetic algorithms to develop electronic countermeasures using integrated software models of the target track radar and the jammer. This paper demonstrates the feasibility of this idea by using a genetic algorithm to optimize the parameters of a range gate pull-off electronic countermeasure technique to break the target lock of a generic radar split gate range tracker.

  5. Optical techniques in optogenetics

    NASA Astrophysics Data System (ADS)

    Mohanty, Samarendra K.; Lakshminarayananan, Vasudevan

    2015-07-01

    Optogenetics is an innovative technique for optical control of cells. This field has exploded over the past decade or so and has given rise to great advances in neuroscience. A variety of applications both from the basic and applied research have emerged, turning the early ideas into a powerful paradigm for cell biology, neuroscience, and medical research. This review aims at highlighting the basic concepts that are essential for a comprehensive understanding of optogenetics and some important biological/biomedical applications. Further, emphasis is placed on advancement in optogenetics-associated light-based methods for controlling gene expression, spatially controlled optogenetic stimulation and detection of cellular activities.

  6. Diamond Anvil Cell Techniques

    NASA Astrophysics Data System (ADS)

    Piermarini, Gasper J.

    It has often been said that scientific advances are made either in a dramatic and revolutionary way, or, as in the case of the diamond anvil cell (DAC), in a slow and evolutionary manner over a period of several years. For more than 2 decades, commencing in 1958, the DAC developed stepwise from a rather crude qualitative instrument to the sophisticated quantitative research tool it is today, capable of routinely producing sustained static pressures in the multi-megabar range and readily adaptable to numerous scientific measurement techniques because of its optical accessibility, miniature size, and portability.

  7. Landing techniques in volleyball.

    PubMed

    Lobietti, Roberto; Coleman, Simon; Pizzichillo, Eduardo; Merni, Franco

    2010-11-01

    Knee injuries such as anterior cruciate ligament lesions and patellar tendonitis are very frequent in volleyball, and are often attributed to micro traumas that occur during the landing phase of airborne actions. The aim of the present study was to compare different jumping activities during official men's and women's volleyball games. Twelve top-level matches from the Italian men's and women's professional leagues were analysed. The jumps performed during the games were classified according to the landing technique used by the player (left or right foot or both feet together), court position, and ball trajectory. Chi-square analyses were performed to detect differences in landing techniques between the sexes, court positions, and trajectories when serving, attacking, blocking, and setting. Significant differences (P < 0.05) were found between the sexes for block, set, and spike but not for the jump serve. The frequency of landings on one foot was related to court position and the trajectory of the sets: when spiking faster sets, the players were more likely to use a one-footed landing. The present results should help coaches and physiotherapists to devise appropriate training and prevention programmes, and reveal the need for further detailed biomechanical investigations of the relationships between landings and knee injuries.

  8. Code Optimization Techniques

    SciTech Connect

    MAGEE,GLEN I.

    2000-08-03

    Computers transfer data in a number of different ways. Whether through a serial port, a parallel port, over a modem, over an ethernet cable, or internally from a hard disk to memory, some data will be lost. To compensate for that loss, numerous error detection and correction algorithms have been developed. One of the most common error correction codes is the Reed-Solomon code, which is a special subset of BCH (Bose-Chaudhuri-Hocquenghem) linear cyclic block codes. In the AURA project, an unmanned aircraft sends the data it collects back to earth so it can be analyzed during flight and possible flight modifications made. To counter possible data corruption during transmission, the data is encoded using a multi-block Reed-Solomon implementation with a possibly shortened final block. In order to maximize the amount of data transmitted, it was necessary to reduce the computation time of a Reed-Solomon encoding to three percent of the processor's time. To achieve such a reduction, many code optimization techniques were employed. This paper outlines the steps taken to reduce the processing time of a Reed-Solomon encoding and the insight into modern optimization techniques gained from the experience.

  9. Oxygenated kidney preservation techniques.

    PubMed

    Hosgood, Sarah A; Nicholson, Harriet F L; Nicholson, Michael L

    2012-03-15

    Improving preservation techniques to minimize injury is of particular importance in organs from marginal donors. Since the introduction of transplantation and routine use of hypothermic temperatures for kidney preservation, there has been much debate on whether it is necessary to add oxygen to support the low level of metabolism under these conditions. Supplementing the kidney with oxygen during hypothermic preservation is not common practice. However, there is evidence to support its application. Oxygen can be added by various techniques such as retrograde persufflation whereby filtered and humidified oxygen is bubbled through the vasculature; under hyperbaric conditions using specialized pressurized chambers; during hypothermic machine perfusion; with the addition of oxygen carriers; and under normothermic conditions. Evidence suggests that oxygenation is particularly beneficial in restoring cellular levels of adenosine triphosphate after kidneys have been subjected to warm or cold ischemic injury. However, under normal conditions, the benefits are less convincing, but the evidence is insufficient to draw any conclusions. This overview explores the ways in which oxygen can be administered during preservation in experimental and clinical models of kidney transplantation.

  10. Information hiding technique

    NASA Astrophysics Data System (ADS)

    Younger, Michael; Budulas, Peter P.; Young, Stuart H.

    2002-08-01

    Spread spectrum communication techniques have been recognized as a viable method to gain an advantage in interference environments. Many military-oriented systems have been initiated, and some civil systems have been attempted. Spread spectrum allows the ability to hide the signal of interest below or in the noise floor, so as not to be detected. A spread spectrum system is one in which the transmitted signal is spread over a wide frequency band, much wider, in fact, than the minimum bandwidth required to transmit the information being sent. We at Army Research Lab (ARL) are proposing using the same technique on the Internet with port hopping. The information would be transmitted in data packets over multiple ports. The port used would vary per packet or per session basis. This port hopping gives you and the recipients the ability to take datagram's and spread them out over a multitude of ports. This will hide information among the Internet noise. This will allow trusted communications between the transmitter and receiver because of the port coding sequence. There are 64K possible ports to span datagram. Jamming of transmission would be limiting the ability of the sniffer/listener. Also, the listener will find it difficult to use a man in the middle attach, since the data will be spread over multiple ports and only the receiver and transmitter will know the specific port sequencing for the datagram.

  11. ALMA High Frequency Techniques

    NASA Astrophysics Data System (ADS)

    Meyer, J. D.; Mason, B.; Impellizzeri, V.; Kameno, S.; Fomalont, E.; Chibueze, J.; Takahashi, S.; Remijan, A.; Wilson, C.; ALMA Science Team

    2015-12-01

    The purpose of the ALMA High Frequency Campaign is to improve the quality and efficiency of science observing in Bands 8, 9, and 10 (385-950 GHz), the highest frequencies available to the ALMA project. To this end, we outline observing modes which we have demonstrated to improve high frequency calibration for the 12m array and the ACA, and we present the calibration of the total power antennas at these frequencies. Band-to-band (B2B) transfer and bandwidth switching (BWSW), techniques which improve the speed and accuracy of calibration at the highest frequencies, are most necessary in Bands 8, 9, and 10 due to the rarity of strong calibrators. These techniques successfully enable increased signal-to-noise on the calibrator sources (and better calibration solutions) by measuring the calibrators at lower frequencies (B2B) or in wider bandwidths (BWSW) compared to the science target. We have also demonstrated the stability of the bandpass shape to better than 2.4% for 1 hour, hidden behind random noise, in Band 9. Finally, total power observing using the dual sideband receivers in Bands 9 and 10 requires the separation of the two sidebands; this procedure has been demonstrated in Band 9 and is undergoing further testing in Band 10.

  12. [Neuromodulation - new techniques].

    PubMed

    Heinze, K; van Ophoven, A

    2015-03-01

    Neuromodulative procedures have become an inherent component in the therapy of functional urinary bladder and pelvic floor function disorders. Sacral neuromodulation has been used in Germany for more than 20 years and reresents the standard neuromodulative therapy. Technical improvements in the field of test stimulation and the phasing out of the large pulse generator models represent current changes with the resulting advantages and disadvantages. Pudendal neuromodulation (PNM) has been known for many years as a procedure for treatment of chronic diseases of the urinary bladder and the lesser pelvis and is predominantly used as second-line neuromodulative therapy; however, for pelvic pain syndromes and in particular for pudendal neuralgia, it represents a promising minimally invasive first-line therapy. Due to the technically demanding puncture procedure, PNM has so far only been used in Germany in specialized centers. Through the development of new operation techniques, the prerequisites for a wider multicentric use, with the future aim of approval of the procedure, have been achieved. External transdermal pudendal neuromodulation is a promising therapeutic approach and after further testing in randomized studies could find an application as a conservative step before minimally invasive pudendal neuromodulation. Although the technique of laparoscopic electrode placement on neural structures of the lesser pelvis is technically attractive, it predominantly finds a monocentric use and must in due course be critically compared with established minimally invasive procedures.

  13. Development of a direct fabrication technique for full-shell x-ray optics

    NASA Astrophysics Data System (ADS)

    Gubarev, M.; Kolodziejczak, J. K.; Griffith, C.; Roche, J.; Smith, W. S.; Kester, T.; Atkins, C.; Arnold, W.; Ramsey, B.

    2016-07-01

    Future astrophysical missions will require fabrication technology capable of producing high angular resolution x-ray optics. A full-shell direct fabrication approach using modern robotic polishing machines has the potential for producing high resolution, light-weight and affordable x-ray mirrors that can be nested to produce large collecting area. This approach to mirror fabrication, based on the use of the metal substrates coated with nickel phosphorous alloy, is being pursued at MSFC. A model of the wear pattern as a function of numerous physical parameters is developed and verified using a mandrel sample. The results of the polishing experiments are presented.

  14. Advanced Coating Removal Techniques

    NASA Technical Reports Server (NTRS)

    Seibert, Jon

    2006-01-01

    An important step in the repair and protection against corrosion damage is the safe removal of the oxidation and protective coatings without further damaging the integrity of the substrate. Two such methods that are proving to be safe and effective in this task are liquid nitrogen and laser removal operations. Laser technology used for the removal of protective coatings is currently being researched and implemented in various areas of the aerospace industry. Delivering thousands of focused energy pulses, the laser ablates the coating surface by heating and dissolving the material applied to the substrate. The metal substrate will reflect the laser and redirect the energy to any remaining protective coating, thus preventing any collateral damage the substrate may suffer throughout the process. Liquid nitrogen jets are comparable to blasting with an ultra high-pressure water jet but without the residual liquid that requires collection and removal .As the liquid nitrogen reaches the surface it is transformed into gaseous nitrogen and reenters the atmosphere without any contamination to surrounding hardware. These innovative technologies simplify corrosion repair by eliminating hazardous chemicals and repetitive manual labor from the coating removal process. One very significant advantage is the reduction of particulate contamination exposure to personnel. With the removal of coatings adjacent to sensitive flight hardware, a benefit of each technique for the space program is that no contamination such as beads, water, or sanding residue is left behind when the job is finished. One primary concern is the safe removal of coatings from thin aluminum honeycomb face sheet. NASA recently conducted thermal testing on liquid nitrogen systems and found that no damage occurred on 1/6", aluminum substrates. Wright Patterson Air Force Base in conjunction with Boeing and NASA is currently testing the laser remOval technique for process qualification. Other applications of liquid

  15. [Survival analysis techniques].

    PubMed

    Bustamante-Teixeira, Maria Teresa; Faerstein, Eduardo; Latorre, Maria do Rosário

    2002-01-01

    Statistical methods known as survival analyses are useful for analyzing time-related events, in which time from a benchmark event to an endpoint is the focus of interest. Survival analysis describes not only patient survival statistics (as suggested by the name), but also other dichotomous outcomes such as time of remission, time of breastfeeding, etc. This paper discusses survival analysis techniques, commenting and comparing their utilization, especially in the field of oncology. It also presents and discusses types of epidemiological studies and data sources to which this type of analysis is applied. The authors take into account the difference between hospital-based or clinical series and population-based approaches. Interpretation of results is also discussed.

  16. Extended Ewald summation technique

    NASA Astrophysics Data System (ADS)

    Kylänpää, Ilkka; Räsänen, Esa

    2016-09-01

    We present a technique to improve the accuracy and to reduce the computational labor in the calculation of long-range interactions in systems with periodic boundary conditions. We extend the well-known Ewald method by using a linear combination of screening Gaussian charge distributions instead of only one. This enables us to find faster converging real-space and reciprocal space summations. The combined simplicity and efficiency of our method is demonstrated, and the scheme is readily applicable to large-scale periodic simulations, classical as well as quantum. Moreover, apart from the required a priori optimization the method is straightforward to include in most routines based on the Ewald method within, e.g., density-functional, molecular dynamics, and quantum Monte Carlo calculations.

  17. Data flow modeling techniques

    NASA Technical Reports Server (NTRS)

    Kavi, K. M.

    1984-01-01

    There have been a number of simulation packages developed for the purpose of designing, testing and validating computer systems, digital systems and software systems. Complex analytical tools based on Markov and semi-Markov processes have been designed to estimate the reliability and performance of simulated systems. Petri nets have received wide acceptance for modeling complex and highly parallel computers. In this research data flow models for computer systems are investigated. Data flow models can be used to simulate both software and hardware in a uniform manner. Data flow simulation techniques provide the computer systems designer with a CAD environment which enables highly parallel complex systems to be defined, evaluated at all levels and finally implemented in either hardware or software. Inherent in data flow concept is the hierarchical handling of complex systems. In this paper we will describe how data flow can be used to model computer system.

  18. DNA Vaccination Techniques.

    PubMed

    Fissolo, Nicolás; Montalban, Xavier; Comabella, Manuel

    2016-01-01

    Multiple sclerosis (MS) is the most common inflammatory, demyelinating, and neurodegenerative disorder of the central nervous system (CNS) in humans. Although the etiology of MS remains unknown, several lines of evidence support the notion that autoimmunity against components of the myelin sheath plays a major role in susceptibility to and development of the disease. At present, there are no approved MS therapies aimed specifically toward downregulating antigen-specific autoreactive immune cells. One antigen-specific approach that appears promising for the treatment of MS is DNA vaccination. This technique has demonstrated efficacy in clinical trials while maintaining safety.Here, we describe the generation of DNA vaccines containing immunologically relevant antigens of MS. Moreover, we present a detailed protocol for the prophylactic and therapeutic administration of DNA vaccines via intramuscular injection targeting on the development of experimental autoimmune encephalomyelitis (EAE), an animal model resembling MS.

  19. Techniques for fire detection

    NASA Technical Reports Server (NTRS)

    Bukowski, Richard W.

    1987-01-01

    An overview is given of the basis for an analysis of combustable materials and potential ignition sources in a spacecraft. First, the burning process is discussed in terms of the production of the fire signatures normally associated with detection devices. These include convected and radiated thermal energy, particulates, and gases. Second, the transport processes associated with the movement of these from the fire to the detector, along with the important phenomena which cause the level of these signatures to be reduced, are described. Third, the operating characteristics of the individual types of detectors which influence their response to signals, are presented. Finally, vulnerability analysis using predictive fire modeling techniques is discussed as a means to establish the necessary response of the detection system to provide the level of protection required in the application.

  20. Nondestructive Acoustic Imaging Techniques

    NASA Astrophysics Data System (ADS)

    Schmitz, Volker

    Acoustic imaging techniques are used in the field of nondestructive testing of technical components to measure defects such as lack of side wall fusion or cracks in welded joints. Data acquisition is performed by a remote-controlled manipulator and a PC for the mass storage of the high-frequency time-of-flight data at each probe position. The quality of the acoustic images and the interpretation relies on the proper understanding of the transmitted wave fronts and the arrangement of the probes in pulse-echo mode or in pitch-and-catch arrangement. The use of the Synthetic Aperture Focusing Technique allows the depth-dependent resolution to be replaced by a depth-independent resolution and the signal-to-noise ratio to be improved. Examples with surface-connected cracks are shown to demonstrate the improved features. The localization accuracy could be improved by entering 2-dimensional or 3-dimensional reconstructed data into the environment of a 3-dimensional CAD drawing. The propagation of ultrasonic waves through austenitic welds is disturbed by the anisotropic and inhomogeneous structure of the material. The effect is more or less severe depending upon the longitudinal or shear wave modes. To optimize the performance of an inspection software tool, a 3-dimensional CAD-Ray program has been implemented, where the shape of the inhomogeneous part of a weld can be simulated together with the grain structure based on the elastic constants. Ray-tracing results are depicted for embedded and for surface-connected defects.

  1. Electroform replication used for multiple X-ray mirror production

    NASA Technical Reports Server (NTRS)

    Kowalski, M. P.; Ulmer, M. P.; Purcell, W. R., Jr.; Loughlin, J. E. A.

    1984-01-01

    The electroforming technique for producing X-ray mirrors is described, and results of X-ray tests performed on copies made from a simple conical mandrel are reported. The design of the mandrel is depicted and the total reflectivity as well as the full-wave half modulation resolution are shown as a function of energy. The reported work has improved on previous studies by providing smaller grazing angles, making measurements at higher energies, producing about four times as many replicas from one mandrel, and obtaining better angular resolution.

  2. Process for making electroformed stents

    DOEpatents

    Hines, Richard A.

    2000-02-01

    This invention is directed to an expandable stent useful for implantation into an artery or the like. The stents are made using electroforming techniques in which an electrically-conductive mandrel is coated with a suitable resist material, after which the resist is exposed to an appropriate light pattern and frequency so as to form a stent pattern in the resist. The mandrel is then electroplated with a suitable stent material. The mandrel is etched away once a sufficient layer of stent material is deposited, leaving a completed stent.

  3. Programing techniques for CDC equipment

    NASA Technical Reports Server (NTRS)

    Newsom, J. R.; Tiffany, S. H.

    1979-01-01

    Five techniques reduce core requirements for fast batch turnaround time and interactive-terminal capability. Same techniques increase program versatility, decrease problem-configuration dependence, and facilitate interprogram communication.

  4. Programing techniques for CDC equipment

    NASA Technical Reports Server (NTRS)

    Newsom, J. R.; Tiffany, S. H.

    1979-01-01

    Five techniques reduce core requirements for fast batch turnaround time and interactive-terminal capability. Same techniques increase program versatility, decrease problem-configuration dependence, and facilitate interprogram communication.

  5. Technique Selectively Represses Immune System

    MedlinePlus

    ... Research Matters December 3, 2012 Technique Selectively Represses Immune System Myelin (green) encases and protects nerve fibers (brown). A new technique prevents the immune system from attacking myelin in a mouse model of ...

  6. A Topological Technique for Regionalization.

    ERIC Educational Resources Information Center

    Brantingham, Patricia L.; Brantingham, Paul J.

    1978-01-01

    Presents a mathematical technique for building perceptual models of urban areas. Uses techniques to model perceptual neighborhoods within a city and to explore how residential burglary rates vary between the interiors and borders of the neighborhood. (Author/MA)

  7. Improved Search Techniques

    NASA Technical Reports Server (NTRS)

    Albornoz, Caleb Ronald

    2012-01-01

    Thousands of millions of documents are stored and updated daily in the World Wide Web. Most of the information is not efficiently organized to build knowledge from the stored data. Nowadays, search engines are mainly used by users who rely on their skills to look for the information needed. This paper presents different techniques search engine users can apply in Google Search to improve the relevancy of search results. According to the Pew Research Center, the average person spends eight hours a month searching for the right information. For instance, a company that employs 1000 employees wastes $2.5 million dollars on looking for nonexistent and/or not found information. The cost is very high because decisions are made based on the information that is readily available to use. Whenever the information necessary to formulate an argument is not available or found, poor decisions may be made and mistakes will be more likely to occur. Also, the survey indicates that only 56% of Google users feel confident with their current search skills. Moreover, just 76% of the information that is available on the Internet is accurate.

  8. Fenestration obscuration techniques

    NASA Astrophysics Data System (ADS)

    Smalley, Michael

    2007-10-01

    There are situations where it is advantageous to visually obscure through glass, to an external observer, the movement of people within a well lit room. It may be that the building use has changed or existing measures which had provided obscuration such as 'Bomb-blast' curtains have been discontinued. Recognising that implemented solutions must create the minimum disruption to outward visibility and involve the least procedural effort (be simple to use), the Centre for Protection of National Infrastructure, CPNI, commissioned this study, defining key requirements including: (a) Automatic or simple manual operation (b) Obscuration of movement within the building from outside (c) Varying levels of obscuration depending on the difference in internal and external light levels. (d) Minimum disruption to outward visibility (e) Acceptable for use on heritage and iconic sites (f) Easy to retrofit (g) Low cost This report reviews earlier work carried out into the protection of Guardrooms by the use of lighting techniques coupled with the use of reflective and screen printed films. Other innovative solutions including Electrochromatic controllable glazing which may prove more appropriate to office and commercial buildings are also considered. It is seen that some measures, (window films or blinds), are cost effective and unsophisticated while more complex automatic systems using reactive glazing can offer critical design advantages. It must be noted however that some of the key requirements are mutually exclusive and any solution chosen will always be a compromise based on client needs and circumstances.

  9. Sample preparation techniques.

    PubMed

    Baumgartner, W A; Hill, V A

    1993-12-01

    Evidentiary false positives are caused by passive exposure to drugs in the environment rather than by active use of drugs. The avoidance of such positives is essential for both hair and urine analysis. Hair analysis enjoys the advantage over urinalysis in having a number of approaches for making this distinction. These include: methylene blue staining of the hair specimen for selecting the appropriate wash solvent; application of hair digestion techniques for the complete release of chemically unaltered analytes; the determination of three diagnostic ratios from wash and digestion data; the measurement of metabolite:drug ratios; the use of cut-off levels setting the limits for passive endogenous drug exposure; reproducibility of results (including segmental analysis) with a newly collected hair specimen; and the reporting of results as either negative, positive, or contaminated. Our sample preparation procedures have been effectively applied to the analyses of nearly 200,000 specimens, i.e. to approximately one million drug analyses for cocaine, opiates, methamphetamine, phencyclidine or marijuana. On the basis of this experience we conclude that hair analysis is a safe and effective method for workplace drug testing.

  10. Nozzle fabrication technique

    NASA Technical Reports Server (NTRS)

    Wells, Dennis L. (Inventor)

    1991-01-01

    A block of electrically conductive material which is to be formed into a body with internal and/or external surfaces that approximate hyperboloids of one sheet is placed so that its axis is set at a predetermined skew angle with relation to a traveling EDM electrode wire. The electrode wire is then moved into cutting proximity of the body wire. Thereafter, by revolving the body about its own axis, the external and/or internal surfaces of the body will be cut into an approximate hyperbolic surface of revolution depending upon whether the body is positioned with the cutting wire outside of the body or in a previously formed longitudinal passage in the body. As an alternative technique, elongated channels can also be cut into the wall of the body by successively orienting the body to a selected number of angular positions, with the electrode wire being either outside of the body or in a previously formed passage in the body. At each of these angular positions, the electrode wire is moved orthogonally with respect to the axis of the wire, while both the body axis skew angle and the rotational position about that axis is controlled by cutting a channel or groove in the body to relieve stresses in the body material or to convey a coolant fluid.

  11. Techniques of Electrode Fabrication

    NASA Astrophysics Data System (ADS)

    Guo, Liang; Li, Xinyong; Chen, Guohua

    Electrochemical applications using many kinds of electrode materials as an advanced oxidation/reduction technique have been a focus of research by a number of groups during the last two decades. The electrochemical approach has been adopted successfully to develop various environmental applications, mainly including water and wastewater treatment, aqueous system monitoring, and solid surface analysis. In this chapter, a number of methods for the fabrication of film-structured electrode materials were selectively reviewed. Firstly, the thermal decomposition method is briefly described, followed by introducing chemical vapor deposition (CVD) strategy. Especially, much attention was focused on introducing the methods to produce diamond novel film electrode owing to its unique physical and chemical properties. The principle and influence factors of hot filament CVD and plasma enhanced CVD preparation were interpreted by refereeing recent reports. Finally, recent developments that address electro-oxidation/reduction issues and novel electrodes such as nano-electrode and boron-doped diamond electrode (BDD) are presented in the overview.

  12. Nozzle fabrication technique

    NASA Technical Reports Server (NTRS)

    Wells, Dennis L. (Inventor)

    1989-01-01

    A block of electrically-conductive material which is to be formed into a body with internal and/or external surfaces that approximate hyperboloids of one sheet is placed so that its axis is set at a predetermined skew angle with relation to a travelling EDM electrode wire and the electrode wire is then moved into cutting proximity of the body. Thereafter, by revolving the body about its own axis, the external and/or internal surfaces of the body will be cut into an approximate hyperbolic surface of revolution depending upon whether the body is positioned with the cutting wire outside of the body or in a previously-formed longitudinal passage in the body. As an alternative technique, elongated channels can also be cut into the walls of the body by successively orienting the body to a selected number of angular positions with the electrode wire being either outside of the body or in a previously-formed passage in the body. At each of these angular positions, the electrode wire is moved orthogonally with respect to the axis of the wire while both the body axis skew angle and the rotational position about that axis are controlled for cutting a channel or groove in the body as required to relieve stresses in the material of the body or to convey a coolant fluid.

  13. Laser Scar Management Technique

    PubMed Central

    Ohshiro, Toshio; Sasaki, Katsumi

    2013-01-01

    Background and Aims: Scars are common and cause functional problems and psychological morbidity. Recent advances in optical technologies have produced various laser systems capable of revising the appearance of scars from various etiologies to optimize their appearance. Methods: Laser treatment can commence as early as the time of the initial injury and as late as several years after the injury. Several optical technologies are currently available and combined laser/light treatments are required for treatment of scars. Since 2006, we have set up a scar management department in our clinic and more than 2000 patients have been treated by our combined laser irradiation techniques. Herein, we review several available light technologies for treatment of surgical, traumatic, and inflammatory scars, and discuss our combined laser treatment of scars, based upon our clinical experience. Results and Conclusions: Because scars have a variety of potential aetiologies and take a number of forms, no single approach can consistenty provide good scar treatment and management. The combination of laser and devices is essential, the choice of wavelength and approach being dictated by each patient as an individual. PMID:24511202

  14. Microorganism identification technique

    SciTech Connect

    Sillman, R. E.

    1985-07-02

    An identification technique for micro-organisms in which a dilute solution of a culture medium containing an unknown micro-organism has added thereto an emissive agent such as a radioactive amino acid to produce a mix of emissive products that depends on the metabolic mechanism of the micro-organism. After a predetermined incubation period, the reaction is arrested and the solution layered onto a gel plate where it is subjected to electrophoresis. The plate is then autoradiographed by exposing the gel to a sensitive photographic film for a period sufficient to produce thereon a characteristic band pattern functioning as an identifier for the micro-organism. Identification may be effected by comparing the identifier for the unknown with a collection of identifiers for known micro-organisms to find a match with one of these known identifiers. The comparison is preferably carried out by scanning the unknown identifier to produce a signal which is compared with signals representing known identifiers stored in a computer which, when a match is found, yields identification data. Alternatively, the emissive products, after separation, may be detected by direct scanning to provide an identifier signal for computer processing.

  15. COHERENT-LIGHT RECORDING TECHNIQUES.

    DTIC Science & Technology

    The purpose of this report is to summarize, define and demonstrate techniques necessary for the application of coherent light to the problems of...Investigations into such areas as the coherent light source itself, modulation, deflection or scanning techniques, readout techniques and the evaluation of recording media are reported.

  16. Ethical Use of Gestalt Techniques.

    ERIC Educational Resources Information Center

    Given, Jane A.

    The purpose of this paper is to engender a healthy respect for Gestalt theory and techniques and the use of the techniques in the client's best interest and in the interest of positive professional and self-development in the practitioner. An overview of Gestalt techniques is provided, concentrating on the two category divisions of experiments and…

  17. Dose Reduction Techniques

    SciTech Connect

    WAGGONER, L.O.

    2000-05-16

    As radiation safety specialists, one of the things we are required to do is evaluate tools, equipment, materials and work practices and decide whether the use of these products or work practices will reduce radiation dose or risk to the environment. There is a tendency for many workers that work with radioactive material to accomplish radiological work the same way they have always done it rather than look for new technology or change their work practices. New technology is being developed all the time that can make radiological work easier and result in less radiation dose to the worker or reduce the possibility that contamination will be spread to the environment. As we discuss the various tools and techniques that reduce radiation dose, keep in mind that the radiological controls should be reasonable. We can not always get the dose to zero, so we must try to accomplish the work efficiently and cost-effectively. There are times we may have to accept there is only so much you can do. The goal is to do the smart things that protect the worker but do not hinder him while the task is being accomplished. In addition, we should not demand that large amounts of money be spent for equipment that has marginal value in order to save a few millirem. We have broken the handout into sections that should simplify the presentation. Time, distance, shielding, and source reduction are methods used to reduce dose and are covered in Part I on work execution. We then look at operational considerations, radiological design parameters, and discuss the characteristics of personnel who deal with ALARA. This handout should give you an overview of what it takes to have an effective dose reduction program.

  18. Advanced qualification techniques

    SciTech Connect

    Winokur, P.S; Shaneyfelt, M.R.; Meisenheimer, T.L.; Fleetwood, D.M.

    1993-12-01

    This paper demonstrates use of the Qualified Manufacturers List (QML) methodology to qualify commercial and military microelectronics for use in space applications. QML ``builds in`` the hardness of product through statistical process control (SPC) of technology parameters relevant to the radiation response, test structure to integrated circuit (IC) correlations, and techniques for extrapolating laboratory test results to low-dose-rate space scenarios. Each of these elements is demonstrated and shown to be a cost-effective alternative to expensive end-of-line IC testing. Several examples of test structured-IC correlations are provided and recent work on complications arising from transistor scaling and geometry is discussed. The use of a 10-keV x-ray wafer-level test system to support SPC and establish ``process capability`` is illustrated and a comparison of 10-keV x-ray and Co{sup 60} gamma irradiations is provided for a wide range of CMOS technologies. The x-ray tester is shown to be cost-effective and its use in lot acceptance/qualification is recommended. Finally, a comparison is provided between MIL-STD-883D, Test Method 1019.4, which governs the testing of packaged semiconductor microcircuits in the DoD, and ESA/SSC Basic Specification No. 22900, Europe`s Total Dose Steady-State Irradiation Test Method. Test Method 1019.4 focuses on conservative estimates of MOS hardness for space and tactical applications, while Basic Specification 22900 focuses on improved simulation of low-dose-rate space environments.

  19. Techniques in Broadband Interferometry

    SciTech Connect

    Erskine, D J

    2004-01-04

    This is a compilation of my patents issued from 1997 to 2002, generally describing interferometer techniques that modify the coherence properties of broad-bandwidth light and other waves, with applications to Doppler velocimetry, range finding, imaging and spectroscopy. Patents are tedious to read in their original form. In an effort to improve their readability I have embedded the Figures throughout the manuscript, put the Figure captions underneath the Figures, and added section headings. Otherwise I have resisted the temptation to modify the words, though I found many places which could use healthy editing. There may be minor differences with the official versions issued by the US Patent and Trademark Office, particularly in the claims sections. In my shock physics work I measured the velocities of targets impacted by flyer plates by illuminating them with laser light and analyzing the reflected light with an interferometer. Small wavelength changes caused by the target motion (Doppler effect) were converted into fringe shifts by the interferometer. Lasers having long coherence lengths were required for the illumination. While lasers are certainly bright sources, and their collimated beams are convenient to work with, they are expensive. Particularly if one needs to illuminate a wide surface area, then large amounts of power are needed. Orders of magnitude more power per dollar can be obtained from a simple flashlamp, or for that matter, a 50 cent light bulb. Yet these inexpensive sources cannot practically be used for Doppler velocimetry because their coherence length is extremely short, i.e. their bandwidth is much too wide. Hence the motivation for patents 1 & 2 is a method (White Light Velocimetry) for allowing use of these powerful but incoherent lamps for interferometry. The coherence of the illumination is modified by passing it through a preparatory interferometer.

  20. Fog dispersion. [charged particle technique

    NASA Technical Reports Server (NTRS)

    Christensen, L. S.; Frost, W.

    1980-01-01

    The concept of using the charged particle technique to disperse warm fog at airports is investigated and compared with other techniques. The charged particle technique shows potential for warm fog dispersal, but experimental verification of several significant parameters, such as particle mobility and charge density, is needed. Seeding and helicopter downwash techniques are also effective for warm fog disperals, but presently are not believed to be viable techniques for routine airport operations. Thermal systems are currently used at a few overseas airports; however, they are expensive and pose potential environmental problems.

  1. Aseptic technique in microgravity.

    PubMed

    McCuaig, K

    1992-11-01

    Within the next decade, the United States will launch a space station into low Earth orbit as a preliminary step toward a manned mission to Mars. Provision of asepsis in the unique microgravity environment, essential in operative and invasive procedures, is addressed. An assessment of conventional terrestrial aseptic methods and possible modifications for a microgravity environment was done during the microgravity portion of parabolic flight on NASA KC-135 aircraft. During 110 parabolas on three flight days, a "surgical team" (surgeon, scrub nurse and circulating nurse) using a life size mannequin fastened to a prototype surgical "work station" (operating table), evaluated open and closed gloving (ten parabolas), skin preparation (six parabolas), surgical scrub methods (24 parabolas), gowning (22 parabolas) and draping (48 parabolas). Evaluated were povidone iodine solution, 1 percent povidone iodine detergent, Chloroxylenol with detergent, wet prep soap sponge, a water insoluble iodophor polymer (DuraPrep, 3M), disposable towels, disposable and reusable gowns, large and small disposable drapes with and without adhesive edges, disposable latex surgeon's gloves with and without packaging modifications and restraint mechanisms (tether, swiss seat, waist and foot restraint devices, fairfield and wire clamps and clips). Ease of use, provision of restraint for supplies and personnel and waste disposal were assessed. The literature was reviewed and its relevance to the space environment discussed, including risk factors, environmental contamination, immune status and microbiology. The microgravity environment, limited water supply and restricted operating area mandated that modifications of fabrication and packaging of supplies and technique be made to create and preserve asepsis. Material must meet stringent flammability and off-gassing standards. Either a chlorhexidine or povidone iodine detergent prepackaged brush and sponge would provide an adequate scrub plus

  2. PDV Probe Alignment Technique

    SciTech Connect

    Whitworth, T L; May, C M; Strand, O T

    2007-10-26

    This alignment technique was developed while performing heterodyne velocimetry measurements at LLNL. There are a few minor items needed, such as a white card with aperture in center, visible alignment laser, IR back reflection meter, and a microscope to view the bridge surface. The work was performed on KCP flyers that were 6 and 8 mils wide. The probes used were Oz Optics manufactured with focal distances of 42mm and 26mm. Both probes provide a spot size of approximately 80?m at 1550nm. The 42mm probes were specified to provide an internal back reflection of -35 to -40dB, and the probe back reflections were measured to be -37dB and -33dB. The 26mm probes were specified as -30dB and both measured -30.5dB. The probe is initially aligned normal to the flyer/bridge surface. This provides a very high return signal, up to -2dB, due to the bridge reflectivity. A white card with a hole in the center as an aperture can be used to check the reflected beam position relative to the probe and launch beam, and the alignment laser spot centered on the bridge, see Figure 1 and Figure 2. The IR back reflection meter is used to measure the dB return from the probe and surface, and a white card or similar object is inserted between the probe and surface to block surface reflection. It may take several iterations between the visible alignment laser and the IR back reflection meter to complete this alignment procedure. Once aligned normal to the surface, the probe should be tilted to position the visible alignment beam as shown in Figure 3, and the flyer should be translated in the X and Y axis to reposition the alignment beam onto the flyer as shown in Figure 4. This tilting of the probe minimizes the amount of light from the bridge reflection into the fiber within the probe while maintaining the alignment as near normal to the flyer surface as possible. When the back reflection is measured after the tilt adjustment, the level should be about -3dB to -6dB higher than the probes

  3. Ultra high speed image processing techniques. [electronic packaging techniques

    NASA Technical Reports Server (NTRS)

    Anthony, T.; Hoeschele, D. F.; Connery, R.; Ehland, J.; Billings, J.

    1981-01-01

    Packaging techniques for ultra high speed image processing were developed. These techniques involve the development of a signal feedthrough technique through LSI/VLSI sapphire substrates. This allows the stacking of LSI/VLSI circuit substrates in a 3 dimensional package with greatly reduced length of interconnecting lines between the LSI/VLSI circuits. The reduced parasitic capacitances results in higher LSI/VLSI computational speeds at significantly reduced power consumption levels.

  4. Theorists and Techniques: Connecting Education Theories to Lamaze Teaching Techniques.

    PubMed

    Podgurski, Mary Jo

    2016-01-01

    Should childbirth educators connect education theory to technique? Is there more to learning about theorists than memorizing facts for an assessment? Are childbirth educators uniquely poised to glean wisdom from theorists and enhance their classes with interactive techniques inspiring participant knowledge and empowerment? Yes, yes, and yes. This article will explore how an awareness of education theory can enhance retention of material through interactive learning techniques. Lamaze International childbirth classes already prepare participants for the childbearing year by using positive group dynamics; theory will empower childbirth educators to address education through well-studied avenues. Childbirth educators can provide evidence-based learning techniques in their classes and create true behavioral change.

  5. Classroom Assessment Techniques

    NASA Astrophysics Data System (ADS)

    Narayanan, M.

    2003-12-01

    and the learner should be carefully observed and monitored. Forrest says that Student Portfolios, which document learning in more detail, seldom reveal how teaching contributes to students' progress. Cerbin further indicates that a course portfolio is essentially, a like a manuscript of scholarly work in progress. In this example, it is a work that explains what, how, and why students learn or do not learn in a course. In this paper, the author reports on a dozen techniques that could perhaps be used to document assessment of student learning. References : Cerbin, W. (1993). Fostering a culture of teaching as scholarship. The Teaching Professor, 7(3), 1-2. Edgerton, R., Hutchings, P., & Quinlan, P. (1991). The teaching portfolio: Capturing the scholarship in teaching. Washington, DC: American Association for Higher Education. Forrest, A. (1990). Time will tell: Portfolio-assisted assessment of general education. Washington, DC: American Association for Higher Education. Linn, R., Baker, E., & Dunbar, S. (1991). Complex, Performance-based Assessment: Expectations and Validation Criteria. Educational Researcher, 20 (8), 15-21. Narayanan, M. (2003). Assessment in Higher Education: Partnerships in Learning. Paper presented at the 23rd Annual Lilly Conference on College Teaching, Miami University, Oxford, OH. Seldin, P. (1991). The teaching portfolio. Bolton, MA: Anker. Young, C. O., Sr., & Young, L. H. (1999). Assessing Learning in Interactive Courses. Journal on Excellence in College Teaching, 10 (1), 63-76.

  6. Correlation of cure monitoring techniques

    NASA Astrophysics Data System (ADS)

    Chang, S. S.; Mopsik, F. I.; Hunston, D. L.

    Six different composite matrix or neat resin cure-monitoring methods are presently used to follow the cure process in a model epoxy system, and the results obtained are compared. Differential scanning calorimetry, viscosity monitoring, the ultrasonic shear wave propagation technique, dielectric spectrometry, and two different fluorescence intensity techniques are compared with a view to common traits and differences. Dielectric fluorescence and ultrasonic measurement techniques are noted to be applicable to on-line process monitoring.

  7. Hypersonic Wind Tunnel Test Techniques

    DTIC Science & Technology

    1994-08-01

    AEDC TR-94-6 Hypersonic Wind Tunnel Test Techniques R. K. Matthcws and R. W. Rhudy Calspan CorporatioWAF_,DC Operations 4 August 1994 Final...REPORT TYPE ANn DATES COVERED I AuCluSt 1994 | Final --July 992 - May 1993 4. TITLE AND SUBTITLE Hypersonic Wind Tunnel Test Techniques 5 FUNDING... techniques because of the importance of defining the thermal environment of hypersonic vehicles. An overview of the materials/structures test

  8. Advanced techniques for ladar sensors

    NASA Astrophysics Data System (ADS)

    Schwartz, William C.; Wangler, Richard J.; Condatore, Lawrence A., Jr.

    1995-06-01

    This paper discusses new techniques for providing a `FLIR like', multi-pixel range receiver for applications of control and guidance by an active LADAR system. The major tradeoffs in developing a LADAR sensor with multi-pixel high resolution capabilities using conventional techniques are large size, high cost, or a slow frame rate. SEO has conceived and is currently developing a new receiver technique using a Charge Coupled Device array element that shows great promise for overcoming all of these drawbacks. Although this technique is a new approach for LADAR sensors, it is a concept that has been used for decades in the receivers of common-module FLIR systems.

  9. Helium II level measurement techniques

    NASA Astrophysics Data System (ADS)

    Celik, D.; Hilton, D. K.; Zhang, T.; Van Sciver, S. W.

    2001-05-01

    In this paper, a survey of cryogenic liquid level measurement techniques applicable to superfluid helium (He II) is given. The survey includes both continuous and discrete measurement techniques. A number of different probes and controlling circuits for this purpose have been described in the literature. They fall into one of the following categories: capacitive liquid level gauges, superconducting wire liquid level gauges, thermodynamic (heat transfer-based) liquid level gauges, resistive gauges, ultrasound and transmission line-based level detectors. The present paper reviews these techniques and their suitability for He II service. In addition to these methods, techniques for measuring the total liquid volume and mass gauging are also discussed.

  10. Decision Analysis Using Extended Techniques

    PubMed Central

    Lau, Joseph; Pauker, Stephen G.

    1985-01-01

    Clinical problems are often complex, repetitive and time dependent. Using only the classical decision tree formalism to model such details are often impractical if not impossible. A number of techniques are described here that could be used to reduce the complexity and to improve the representation. A case illustration describes how such techniques may be used.

  11. Field measurements involve various techniques

    SciTech Connect

    Moore, D.P.; Byars, H.G. )

    1990-07-30

    A number of field techniques are available to determine the extent of corrosion on production equipment. This article on oil field corrosion explains the use of corrosion coupons, several types of probes, and various inspection techniques, and shows how to monitor iron content in water.

  12. TECHNIQUES FOR TEACHING CONSERVATION EDUCATION.

    ERIC Educational Resources Information Center

    BROWN, ROBERT E.; MOUSER, G.W.

    CONSERVATION PRINCIPLES, FIELD METHODS AND TECHNIQUES, AND SPECIFIC FIELD LEARNING ACTIVITIES ARE INCLUDED IN THIS REFERENCE VOLUME FOR TEACHERS. CONSERVATION PRINCIPLES INCLUDE STATEMENTS PERTAINING TO (1) SOIL, (2) WATER, (3) FOREST, AND (4) WILDLIFE. FIELD METHODS AND TECHNIQUES INCLUDE (1) PREPARING FOR A FIELD TRIP, (2) GETTING STUDENT…

  13. Numerical grid generation techniques. [conference

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The state of the art in topology and flow geometry is presented. Solution techniques for partial differential equations are reviewed and included developments in coordinate transformations, conformal mapping, and invariant imbeddings. Applications of these techniques in fluid mechanics, flow geometry, boundary value problems, and fluidics are presented.

  14. Visualization Techniques for Intrusion Detection

    DTIC Science & Technology

    2004-04-01

    interactive animated 2D and 3D graphics in an Intrusion Detection (ID) Analysts Workbench prototype. Visualization techniques allow people to see and...Through the use of various types of detection tools and techniques , including signature based network intrusion detection, anomaly based network

  15. Resiliency Techniques in School Practice

    ERIC Educational Resources Information Center

    Molony, Terry; Henwood, Maureen; Gilroy, Shawn

    2010-01-01

    School psychologists can help build resilience in youth in many ways. This article offers a list of some easy techniques to use when working with individuals or groups, most based on basic cognitive-behavior therapy (CBT) techniques. They include: (1) Emotional awareness; (2) Emotional Regulation; (3) Cognitive Flexibility; (4) Self-efficacy; and…

  16. Field techniques for sampling ants

    USDA-ARS?s Scientific Manuscript database

    Ants occur in most environments and ecologists ask a diverse array of questions involving ants. Thus, a key consideration in ant studies is to match the environment and question (and associated environmental variables) to the ant sampling technique. Since each technique has distinct limitations, usi...

  17. Passage Retrieval: A Probabilistic Technique.

    ERIC Educational Resources Information Center

    Melucci, Massimo

    1998-01-01

    Presents a probabilistic technique to retrieve passages from texts having a large size or heterogeneous semantic content. Results of experiments comparing the probabilistic technique to one based on a text segmentation algorithm revealed that the passage size affects passage retrieval performance; text organization and query generality may have an…

  18. Crack and flip phacoemulsification technique.

    PubMed

    Fine, I H; Maloney, W F; Dillman, D M

    1993-11-01

    The crack and flip phacoemulsification technique combines the advantages of circumferential division of the nucleus and nucleofactis techniques. As such, it adds safety and control to the procedure. We describe each of the surgical maneuvers, including machine settings, and explain the rationale for maneuvers and machine settings.

  19. TECHNIQUES FOR TEACHING CONSERVATION EDUCATION.

    ERIC Educational Resources Information Center

    BROWN, ROBERT E.; MOUSER, G.W.

    CONSERVATION PRINCIPLES, FIELD METHODS AND TECHNIQUES, AND SPECIFIC FIELD LEARNING ACTIVITIES ARE INCLUDED IN THIS REFERENCE VOLUME FOR TEACHERS. CONSERVATION PRINCIPLES INCLUDE STATEMENTS PERTAINING TO (1) SOIL, (2) WATER, (3) FOREST, AND (4) WILDLIFE. FIELD METHODS AND TECHNIQUES INCLUDE (1) PREPARING FOR A FIELD TRIP, (2) GETTING STUDENT…

  20. Selected Logistics Models and Techniques.

    DTIC Science & Technology

    1984-09-01

    Programmable Calculator LCC...Program 27 TI-59 Programmable Calculator LCC Model 30 Unmanned Spacecraft Cost Model 31 iv I: TABLE OF CONTENTS (CONT’D) (Subject Index) LOGISTICS...34"" - % - "° > - " ° .° - " .’ > -% > ]*° - LOGISTICS ANALYSIS MODEL/TECHNIQUE DATA MODEL/TECHNIQUE NAME: TI-59 Programmable Calculator LCC Model TYPE MODEL: Cost Estimating DEVELOPED BY:

  1. Precision porcelain jacket crown technique.

    PubMed

    Riley, E J; Sozio, R B; Casthely, F; Wilcko, M T; Sotera, A J

    1975-09-01

    A simple technique for construction of an aluminous porcelain crown has been described. An aluminous core is fabricated without platinum foil on a ceramic refractory die and, when retrieved, serves as a coping on the master cast. The technique and accuracy of fit are illustrated with the fabrication of an aluminous porcelain crown on the Bureau of Standards' full-crown die.

  2. Accuracy of implant impression techniques.

    PubMed

    Assif, D; Marshak, B; Schmidt, A

    1996-01-01

    Three impression techniques were assessed for accuracy in a laboratory cast that simulated clinical practice. The first technique used autopolymerizing acrylic resin to splint the transfer copings. The second involved splinting of the transfer copings directly to an acrylic resin custom tray. In the third, only impression material was used to orient the transfer copings. The accuracy of stone casts with implant analogs was measured against a master framework. The fit of the framework on the casts was tested using strain gauges. The technique using acrylic resin to splint transfer copings in the impression material was significantly more accurate than the two other techniques. Stresses observed in the framework are described and discussed with suggestions to improve clinical and laboratory techniques.

  3. Single Cell Electrical Characterization Techniques

    PubMed Central

    Mansor, Muhammad Asraf; Ahmad, Mohd Ridzuan

    2015-01-01

    Electrical properties of living cells have been proven to play significant roles in understanding of various biological activities including disease progression both at the cellular and molecular levels. Since two decades ago, many researchers have developed tools to analyze the cell’s electrical states especially in single cell analysis (SCA). In depth analysis and more fully described activities of cell differentiation and cancer can only be accomplished with single cell analysis. This growing interest was supported by the emergence of various microfluidic techniques to fulfill high precisions screening, reduced equipment cost and low analysis time for characterization of the single cell’s electrical properties, as compared to classical bulky technique. This paper presents a historical review of single cell electrical properties analysis development from classical techniques to recent advances in microfluidic techniques. Technical details of the different microfluidic techniques are highlighted, and the advantages and limitations of various microfluidic devices are discussed. PMID:26053399

  4. Single Cell Electrical Characterization Techniques.

    PubMed

    Mansor, Muhammad Asraf; Ahmad, Mohd Ridzuan

    2015-06-04

    Electrical properties of living cells have been proven to play significant roles in understanding of various biological activities including disease progression both at the cellular and molecular levels. Since two decades ago, many researchers have developed tools to analyze the cell's electrical states especially in single cell analysis (SCA). In depth analysis and more fully described activities of cell differentiation and cancer can only be accomplished with single cell analysis. This growing interest was supported by the emergence of various microfluidic techniques to fulfill high precisions screening, reduced equipment cost and low analysis time for characterization of the single cell's electrical properties, as compared to classical bulky technique. This paper presents a historical review of single cell electrical properties analysis development from classical techniques to recent advances in microfluidic techniques. Technical details of the different microfluidic techniques are highlighted, and the advantages and limitations of various microfluidic devices are discussed.

  5. Photogrammetric techniques for aerospace applications

    NASA Astrophysics Data System (ADS)

    Liu, Tianshu; Burner, Alpheus W.; Jones, Thomas W.; Barrows, Danny A.

    2012-10-01

    Photogrammetric techniques have been used for measuring the important physical quantities in both ground and flight testing including aeroelastic deformation, attitude, position, shape and dynamics of objects such as wind tunnel models, flight vehicles, rotating blades and large space structures. The distinct advantage of photogrammetric measurement is that it is a non-contact, global measurement technique. Although the general principles of photogrammetry are well known particularly in topographic and aerial survey, photogrammetric techniques require special adaptation for aerospace applications. This review provides a comprehensive and systematic summary of photogrammetric techniques for aerospace applications based on diverse sources. It is useful mainly for aerospace engineers who want to use photogrammetric techniques, but it also gives a general introduction for photogrammetrists and computer vision scientists to new applications.

  6. Theorists and Techniques: Connecting Education Theories to Lamaze Teaching Techniques

    PubMed Central

    Podgurski, Mary Jo

    2016-01-01

    ABSTRACT Should childbirth educators connect education theory to technique? Is there more to learning about theorists than memorizing facts for an assessment? Are childbirth educators uniquely poised to glean wisdom from theorists and enhance their classes with interactive techniques inspiring participant knowledge and empowerment? Yes, yes, and yes. This article will explore how an awareness of education theory can enhance retention of material through interactive learning techniques. Lamaze International childbirth classes already prepare participants for the childbearing year by using positive group dynamics; theory will empower childbirth educators to address education through well-studied avenues. Childbirth educators can provide evidence-based learning techniques in their classes and create true behavioral change. PMID:26848246

  7. Satellite Moisture Retrieval Techniques. Volume 1. Technique Development and Evaluation

    DTIC Science & Technology

    1983-01-01

    VOLUME 2: Atmospheric Sounding Bibliography — NAVENVPREDRSCHFAC CR 83-01( b ) — for listings developed by literature search in the subject area. 19...Contractor Report CR 83-01 (a): Satellite Moisture Retrieval Techniques, Vol 1, Technique Development and Evaluation (2) CR 83-01 ( b ): Vol 2...AND EVALUATION Prepared By: A. Rosenberg, D. B . Hogan, and C. K. Bowman V /, RCA Government Systems Division, Astro-Electronics, Princeton, New

  8. Evaluation of thermophosphor temperature technique

    NASA Astrophysics Data System (ADS)

    Allison, S. W.

    1987-10-01

    For the past year the Enrichment Technology Applications Center (ETAC) of Martin Marietta Energy Systems has performed research and development on the thermographic phosphor method. The effort had two objectives: to provide a detailed error analysis for the thermal phosphor method for envisioned turbine applications; and to evaluate the technique in a laboratory environment in the 400 F to 700 F range by comparison with standard methods. This technique has the potential for solving a number of aerodynamic thermometry needs at the Arnold Engineering Development Center (AEDC). Results place the thermophosphor technique on a firmer practical base from which to launch into more advanced aerodynamic measurement applications.

  9. Low Light Level TV Techniques.

    PubMed

    Gildea, J

    1970-10-01

    As the science of low light level sensing becomes better understood, the demand for systems with this capability has increased considerably in recent years. Low light level television systems are part of these low light sensing devices in which interest has grown. Development of low light level TV systems has, in turn, stimulated technical advances in new tube types with improved performance, development of electronic techniques which enhance the over-all performance, and design techniques which make the system more versatile and adaptable. A general look at some of these developments and techniques gives insight into the versatility and adaptability of low light level TV.

  10. MHV techniques for QED processes

    NASA Astrophysics Data System (ADS)

    Ozeren, Kemal J.; Stirling, W. James

    2005-11-01

    Significant progress has been made in the past year in developing new `MHV' techniques for calculating multiparticle scattering amplitudes in Yang-Mills gauge theories. Most of the work so far has focussed on applications to Quantum Chromodynamics, both at tree and one-loop level. We show how such techniques can also be applied to abelian theories such as QED, by studying the simplest tree-level multiparticle process, e+e-→nγ. We compare explicit results for up to n = 5 photons using both the Cachazo, Svrcek and Witten `MHV rules' and the related Britto-Cachazo-Feng `recursion relation' approaches with those using traditional spinor techniques.

  11. Magnetic tunnel junction pattern technique

    NASA Astrophysics Data System (ADS)

    Chen, Eugene; Schwarz, Benjamin; Choi, Chang Ju; Kula, Witold; Wolfman, Jerome; Ounadjela, Kamel; Geha, Sam

    2003-05-01

    We have developed a magnetic tunnel junction (MTJ) pattern technique that involves transforming the magnetic layer above the tunnel barrier in unwanted areas into an insulator, thus providing insulation between different MTJ devices without suffering common tunnel barrier shorting problems. With this technique, 90%-100% yielding MTJ devices have been observed. MTJ results using this process are superior to an etching based process. Switching distribution of patterned magnetic bits is also narrower using this novel technique. Process control and the ability to stop on the tunnel barrier have been demonstrated.

  12. Introduction: nanoimaging techniques in biology.

    PubMed

    Sousa, Alioscka A; Kruhlak, Michael J

    2013-01-01

    To dissect the astonishing complexity of the biomolecular machinery functioning within a cell, imaging has been an integral tool in biology, allowing researches to "view" the detailed molecular biology responsible for coordinating cellular life. To visualize the molecular components of cellular structures requires, in particular, imaging techniques capable of reaching nanoscale spatial resolutions. Such nanoimaging techniques are the focus of this volume. Chapters in the current volume are divided into four parts and include specialized techniques in the areas of light, electron, and scanning probe microscopy, as well as methodologies employing combinatorial and complementary imaging approaches.

  13. PIGE technique implementation at ININ

    SciTech Connect

    Policroniades, R. Martínez-Quiroz, E.; Méndez-Garrido, B.; Murillo, G.; Moreno, E.; Villaseñor, P.

    2015-07-23

    In this work, we present a general overview about the implementation at ININ of a Particle Induced Gamma Emission (PIGE) analysis technique, based on the bombardment of samples by protons and deuterons at different energies within our tandem accelerator facility. As it is well known, this technique is based on the detection of γ-rays emitted by nuclei in a target following a charged particle irradiation. The main feature of this technique, apart from being non-destructive and low time consuming, is that it allows a multi-elemental analysis of a sample, permitting an isotopic identification of many nuclides. Advances and some preliminary results are presented.

  14. PIGE technique implementation at ININ

    NASA Astrophysics Data System (ADS)

    Policroniades, R.; Martínez-Quiroz, E.; Méndez-Garrido, B.; Murillo, G.; Moreno, E.; Villaseñor, P.

    2015-07-01

    In this work, we present a general overview about the implementation at ININ of a Particle Induced Gamma Emission (PIGE) analysis technique, based on the bombardment of samples by protons and deuterons at different energies within our tandem accelerator facility. As it is well known, this technique is based on the detection of γ-rays emitted by nuclei in a target following a charged particle irradiation. The main feature of this technique, apart from being non-destructive and low time consuming, is that it allows a multi-elemental analysis of a sample, permitting an isotopic identification of many nuclides. Advances and some preliminary results are presented.

  15. Videogrammetric Model Deformation Measurement Technique

    NASA Technical Reports Server (NTRS)

    Burner, A. W.; Liu, Tian-Shu

    2001-01-01

    The theory, methods, and applications of the videogrammetric model deformation (VMD) measurement technique used at NASA for wind tunnel testing are presented. The VMD technique, based on non-topographic photogrammetry, can determine static and dynamic aeroelastic deformation and attitude of a wind-tunnel model. Hardware of the system includes a video-rate CCD camera, a computer with an image acquisition frame grabber board, illumination lights, and retroreflective or painted targets on a wind tunnel model. Custom software includes routines for image acquisition, target-tracking/identification, target centroid calculation, camera calibration, and deformation calculations. Applications of the VMD technique at five large NASA wind tunnels are discussed.

  16. Multigrid techniques for unstructured meshes

    NASA Technical Reports Server (NTRS)

    Mavriplis, D. J.

    1995-01-01

    An overview of current multigrid techniques for unstructured meshes is given. The basic principles of the multigrid approach are first outlined. Application of these principles to unstructured mesh problems is then described, illustrating various different approaches, and giving examples of practical applications. Advanced multigrid topics, such as the use of algebraic multigrid methods, and the combination of multigrid techniques with adaptive meshing strategies are dealt with in subsequent sections. These represent current areas of research, and the unresolved issues are discussed. The presentation is organized in an educational manner, for readers familiar with computational fluid dynamics, wishing to learn more about current unstructured mesh techniques.

  17. Supercooling Water: A Simple Technique.

    ERIC Educational Resources Information Center

    Geer, Ira W.

    1980-01-01

    Describes a technique for the supercooling of water, for use in the science classroom, involving adding common salt to a mixture of ice and water. Several investigations are included for use during (and after) the process of supercooling. (DS)

  18. Radio frequency baseband recording technique

    NASA Technical Reports Server (NTRS)

    Heckman, D. C.

    1970-01-01

    Technique uses a helical-scan video recorder with auxiliary signal-conditioning equipment to provide an inexpensive, high-capacity magnetic tape recording of a 112 channel, phase-locked, multiplexed, baseband signal.

  19. Behavioral Techniques in Foster Care

    ERIC Educational Resources Information Center

    Stein, Theodore J.; Gambrill, Eileen D.

    1976-01-01

    Behavioral modification techniques are used with families of children in foster care as a way of helping them achieve long-range goals for their children. Case examples illustrate the goals, intervention plans, and the outcomes. (Author)

  20. Monitoring by Control Technique - Cyclone

    EPA Pesticide Factsheets

    Stationary source emissions monitoring is required to demonstrate that a source is meeting the requirements in Federal or state rules. This page is about cyclone control techniques used to reduce pollutant emissions.

  1. Modern Observational Techniques for Comets

    NASA Technical Reports Server (NTRS)

    Brandt, J. C. (Editor); Greenberg, J. M. (Editor); Donn, B. (Editor); Rahe, J. (Editor)

    1981-01-01

    Techniques are discussed in the following areas: astrometry, photometry, infrared observations, radio observations, spectroscopy, imaging of coma and tail, image processing of observation. The determination of the chemical composition and physical structure of comets is highlighted.

  2. Acoustic techniques for localizing holdup

    SciTech Connect

    Vnuk, D.

    1996-09-01

    Material that does not come out of a process as product or waste is called holdup. When this is fissile material, its location and quantity must be determined to improve safeguards and security as well as safety at the facility. The most common method for detecting and measuring holdup is with radiation based techniques. When using them, one must consider equipment geometry, geometry of holdup, and effects of background radiation when converting the radiation measurement into a fissile material quantity. We are developing complementary techniques that use tiny acoustic transducers, which are unaffected by background radiation, to improve holdup measurements by aiding in determining the above conversion factors for holdup measurements. Thus far, we have applied three techniques, Acoustic Interferometry, Pulse Echo, and bending Wave Propagation, of which the latter appears most effective. This paper will describe each of these techniques and show how they may ultimately reduce costs and personnel radiation exposure while increasing confidence I and accuracy of holdup measurements.

  3. Submucosal tunneling techniques: current perspectives.

    PubMed

    Kobara, Hideki; Mori, Hirohito; Rafiq, Kazi; Fujihara, Shintaro; Nishiyama, Noriko; Ayaki, Maki; Yachida, Tatsuo; Matsunaga, Tae; Tani, Johji; Miyoshi, Hisaaki; Yoneyama, Hirohito; Morishita, Asahiro; Oryu, Makoto; Iwama, Hisakazu; Masaki, Tsutomu

    2014-01-01

    Advances in endoscopic submucosal dissection include a submucosal tunneling technique, involving the introduction of tunnels into the submucosa. These tunnels permit safer offset entry into the peritoneal cavity for natural orifice transluminal endoscopic surgery. Technical advantages include the visual identification of the layers of the gut, blood vessels, and subepithelial tumors. The creation of a mucosal flap that minimizes air and fluid leakage into the extraluminal cavity can enhance the safety and efficacy of surgery. This submucosal tunneling technique was adapted for esophageal myotomy, culminating in its application to patients with achalasia. This method, known as per oral endoscopic myotomy, has opened up the new discipline of submucosal endoscopic surgery. Other clinical applications of the submucosal tunneling technique include its use in the removal of gastrointestinal subepithelial tumors and endomicroscopy for the diagnosis of functional and motility disorders. This review suggests that the submucosal tunneling technique, involving a mucosal safety flap, can have potential values for future endoscopic developments.

  4. Experimental techniques and measurement accuracies

    SciTech Connect

    Bennett, E.F.; Yule, T.J.; DiIorio, G.; Nakamura, T.; Maekawa, H.

    1985-02-01

    A brief description of the experimental tools available for fusion neutronics experiments is given. Attention is paid to error estimates mainly for the measurement of tritium breeding ratio in simulated blankets using various techniques.

  5. Supercooling Water: A Simple Technique.

    ERIC Educational Resources Information Center

    Geer, Ira W.

    1980-01-01

    Describes a technique for the supercooling of water, for use in the science classroom, involving adding common salt to a mixture of ice and water. Several investigations are included for use during (and after) the process of supercooling. (DS)

  6. Digital Techniques for Laboratory Measurements

    ERIC Educational Resources Information Center

    Dart, S. Leonard

    1975-01-01

    Describes techniques and equipment intended to both improve laboratory measurements and also form a background for more advanced work by introducing the concepts of electronic and digital circuits. (GS)

  7. Monitoring by Control Technique - Condensers

    EPA Pesticide Factsheets

    Stationary source emissions monitoring is required to demonstrate that a source is meeting the requirements in Federal or state rules. This page is about condenser control techniques used to reduce pollutant emissions.

  8. Testing methods and techniques: A compilation

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Mechanical testing techniques, electrical and electronics testing techniques, thermal testing techniques, and optical testing techniques are the subject of the compilation which provides technical information and illustrations of advanced testing devices. Patent information is included where applicable.

  9. Trends in breast reduction technique.

    PubMed

    Wolf, Omer; Westreich, Melvyn; Shalom, Avshalom

    2012-05-01

    There are two main approaches to breast reduction surgery today: the traditional long scar ("Wise-pattern") technique and the more recent short ("vertical") scar technique, which is becoming more popular. During the last two decades there has been a gradual shift between the two techniques, including at our institute. To evaluate the evidence behind this obvious trend. We retrospectively collected data fromarchived hospital charts of all patients who underwent breast reduction surgery during the period 1995-2007. Epidemicological, clinical and postoperative data were analyzed and compared between patients in whom the short scar vs. the long scar techniques was used. During the study period 91 patients underwent breast reduction surgery in our department: 34 with the Wise-pattern breast reduction technique and 57 with the short-scar procedure. There was no significant difference in operative and postoperative data, including length of hospital stay. In some of the categories there was even a slight advantage (but not statistically significant) to the former. The only significant difference was the size of reduction, with a tendencyto prefer the long scar technique for larger reductions; however, with experience gained the limit for short scar reductions was gradually extended to a maximum of 1470 g. We noticed a sharp increase in the safe and uneventful practice of the short scar technique in breast reduction of < or = 1400 g--especially in young women without extreme ptosis. This observation, together with other advantages, namely, reduced scar length, prolonged shape preservation and better breast projection, support the use of this technique.

  10. Immunodiagnostic Techniques for Bacterial Infections

    DTIC Science & Technology

    1981-01-01

    IMMUNODIAGNOSTIC TECHNIQUES FOR BACTERIAL INFECTIONS I E. A. EDWARDS M. W. RYTEL R. L. HILDERBRAND Lo REPORT NO. 77-39 4 .91 :::> NAVAL HEALTH...IMMUNODIAGNOSTIC TECHNIQUES FOR BACTERIAL INFECTIONS - ttEarl A. Edwards, M.S.t Michael W. Rytel, M. D.tt Richard L. Hilderbrand, Ph.D.t Naval Health...Hausler, Jr. (eds), Diagnostic Procedures for BacteriaZ, Mycotic, and Parasitic Infections , 6th Ed. Wash- ington, DC: American Public Health Assn

  11. Comparing techniques for pterygium surgery

    PubMed Central

    Alpay, Atilla; Uğurbaş, Suat Hayri; Erdoğan, Berktuğ

    2009-01-01

    Purpose: To compare various techniques of pterygium surgery including bare sclera, intraoperative mitomycin C application, conjunctival flap reconstruction, and conjunctival autografting technique. Methods: This study is designed to compare 4 currently used techniques in order to determine the complication and recurrence rates after pterygium exision. Included in the study were 77 eyes from 60 patients. Bare sclera technique was used to treat 21 primary pterygia;mitomycin C was used to treat 20 (16 primary, 4 recurrent) pterygia;18 (17 primary, 1 recurrent) pterygia were treated by conjuntival flap reconstruction;and 18 (9 primary, 9 recurrent) pterygia were treated by conjunctival autografting technique. All patients who underwent surgery were followed up for between 6 months and 2 years. Results: Eight recurrences (38.09%) were observed in the bare sclera group whereas there were 5 (25%) recurrences in the mitomycin C group. In the conjunctival flap reconstruction group, 6 (33.33%) recurrences were detected. In the conjunctival autografting group, 3 recurrences were observed. There were no major complications threatening visual ability in the surgical patients. Conclusion: A comparison of the groups demonstrated that the recurrence rate was highest in the bare sclera group, and lowest in conjunctival autografting and mitomycin C treatment groups respectively. Although the conjunctival autografting technique is a more difficult and time consuming technique than the others, cosmetic and surgical results were found to be superior. We advise conjunctival autografting for the treatment of pterygium in view of the high recurrence rates of other techniques, and the possible complications of mitomycin C treatment for benign disease. PMID:19668546

  12. Comparing techniques for pterygium surgery.

    PubMed

    Alpay, Atilla; Uğurbaş, Suat Hayri; Erdoğan, Berktuğ

    2009-01-01

    To compare various techniques of pterygium surgery including bare sclera, intraoperative mitomycin C application, conjunctival flap reconstruction, and conjunctival autografting technique. This study is designed to compare 4 currently used techniques in order to determine the complication and recurrence rates after pterygium exision. Included in the study were 77 eyes from 60 patients. Bare sclera technique was used to treat 21 primary pterygia;mitomycin C was used to treat 20 (16 primary, 4 recurrent) pterygia;18 (17 primary, 1 recurrent) pterygia were treated by conjuntival flap reconstruction;and 18 (9 primary, 9 recurrent) pterygia were treated by conjunctival autografting technique. All patients who underwent surgery were followed up for between 6 months and 2 years. Eight recurrences (38.09%) were observed in the bare sclera group whereas there were 5 (25%) recurrences in the mitomycin C group. In the conjunctival flap reconstruction group, 6 (33.33%) recurrences were detected. In the conjunctival autografting group, 3 recurrences were observed. There were no major complications threatening visual ability in the surgical patients. A comparison of the groups demonstrated that the recurrence rate was highest in the bare sclera group, and lowest in conjunctival autografting and mitomycin C treatment groups respectively. Although the conjunctival autografting technique is a more difficult and time consuming technique than the others, cosmetic and surgical results were found to be superior. We advise conjunctival autografting for the treatment of pterygium in view of the high recurrence rates of other techniques, and the possible complications of mitomycin C treatment for benign disease.

  13. EMP and HPM Suppression Techniques

    DTIC Science & Technology

    2007-11-02

    Previous Results design procedure for quantum tunnelling devices. The first step is to give an accurate derivation of the fundamental tunnelling...number of techniques are presently used. In- cluded are the use of special device and circuit design techniques. Although of definite advantage...TEST SAMPLE PREPARATION Sections: IV-1 Material Fabrication rV-2 Test Cell Design PartV: LABORATORY MEASUREMENTS Sections: V-1 Test

  14. Surgical techniques of olecranon fractures.

    PubMed

    Wilkerson, James A; Rosenwasser, Melvin P

    2014-08-01

    Olecranon fractures are common upper extremity injuries. The vast majority are treated with operative fixation. Many treatment techniques have been described including tension band and plating. This review covers the most commonly used fixation techniques in detail, including pearls and pitfalls with case examples of both successful treatments and potential complications. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  15. Data compression techniques and applications

    NASA Astrophysics Data System (ADS)

    Benelli, G.; Cappellini, V.; Lotti, F.

    1980-02-01

    The paper reviews several data compression methods for signal and image digital processing and transmission, including both established and more recent techniques. Attention is also given to methods of prediction-interpolation, differential pulse code modulation, delta modulation and transformations. The processing of two dimensional data is also considered, and the results of the application of these techniques to space telemetry and biomedical digital signal processing and telemetry systems are presented.

  16. Complete arch implant impression technique.

    PubMed

    Ma, Junping; Rubenstein, Jeffrey E

    2012-06-01

    When making a definitive impression for an arch containing multiple implants, there are many reported techniques for splinting impression copings. This article introduces a splint technique that uses the shim method, which has been demonstrated to reduce laboratory and patient chair time, the number of impression copings and laboratory analogs needed, and the ultimate cost. Copyright © 2012 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  17. Discovering the Botnet Detection Techniques

    NASA Astrophysics Data System (ADS)

    Rahim, Aneel; Bin Muhaya, Fahad T.

    Botnet is a network of compromised computers. It just fellow the master slave concept. Bots are comprised computers and do the tasks what ever their master orders them. Internet Relay Chat (IRC) is used for the communication between the master and bots. Information is also encrypted to avoid the effect of third party. In this paper we discuss the Botnets detection techniques and comparative analysis of these techniques on the basis of DNS query, History data and group activity.

  18. Microscopy techniques in flavivirus research.

    PubMed

    Chong, Mun Keat; Chua, Anthony Jin Shun; Tan, Terence Tze Tong; Tan, Suat Hoon; Ng, Mah Lee

    2014-04-01

    The Flavivirus genus is composed of many medically important viruses that cause high morbidity and mortality, which include Dengue and West Nile viruses. Various molecular and biochemical techniques have been developed in the endeavour to study flaviviruses. However, microscopy techniques still have irreplaceable roles in the identification of novel virus pathogens and characterization of morphological changes in virus-infected cells. Fluorescence microscopy contributes greatly in understanding the fundamental viral protein localizations and virus-host protein interactions during infection. Electron microscopy remains the gold standard for visualizing ultra-structural features of virus particles and infected cells. New imaging techniques and combinatory applications are continuously being developed to push the limit of resolution and extract more quantitative data. Currently, correlative live cell imaging and high resolution three-dimensional imaging have already been achieved through the tandem use of optical and electron microscopy in analyzing biological specimens. Microscopy techniques are also used to measure protein binding affinities and determine the mobility pattern of proteins in cells. This chapter will consolidate on the applications of various well-established microscopy techniques in flavivirus research, and discuss how recently developed microscopy techniques can potentially help advance our understanding in these membrane viruses.

  19. Measurement techniques for liquid metals

    NASA Astrophysics Data System (ADS)

    Ratajczak, M.; Hernández, D.; Richter, T.; Otte, D.; Buchenau, D.; Krauter, N.; Wondrak, T.

    2017-07-01

    The measurement of flow properties of liquid metals, such as flow rate, flow structure and gas distribution, is a challenging task due to the opaqueness, the high temperatures (e. g. 1500 °C for liquid steel or liquid silicon) and the corrosiveness of those fluids. In this paper, a short review about the recent developments of measurement techniques in the framework of the Helmholtz Alliance Liquid Metal Technologies (LIMTECH) is presented. It focuses on the development of contactless inductive measurement techniques exploiting the high electrical conductivity of those melts. These measurement techniques include the contactless inductive flow tomography (CIFT), which is able to reconstruct the mean three-dimensional velocity structure in liquid melts, local Lorentz force velocimetry (local LFV), which enables the local assessment of flows close to the wall, and inductive methods for bubble detection, which are based on mutual inductance tomography (MIT). Additionally, a short overview of contactless inductive flow rate measurement techniques is given. Furthermore, an ultrasound technique called ultrasound transit-time technique (UTTT) will be presented which enables the measurement of position and size of bubbles in large vessels.

  20. [Current techniques in tonsil surgery].

    PubMed

    Coromina Isern, Jordi; Esteller Moré, Eduard

    2010-12-01

    In recent years, consolidation of tonsillar hypertrophy as the principal surgical procedure has led to the emergence of new techniques. Most aim to reduce volume (tonsillectomy or tonsil reduction). These techniques have considerably decreased intra- and postoperative hemorrhages and pain intensity. The present article describes the mechanisms and the advantages and disadvantages of the various techniques, including electro-dissection using electrical scalpels, reduction using a microdebrider, ultrasonic scalpel, radiofrequency (with its different variations) and CO(2) laser. When techniques that reduce tonsil volume are used, the possibility of recurrence of the tonsillar hypertrophy is high if less than 85% of the tonsil is removed. There is also a considerable possibility of infection of the remaining tonsils, whichever technique is used, and therefore these techniques are not valid in the case of repetitive tonsillitis. Recently, alternatives to classical adenoidectomy using adenoid curette have also appeared. Bleeding can be minimized by using a microdebrider, radiofrequency or a blood coagulator. We also discuss the concept of partial adenoidectomy, which is preferred in patients at risk of velopharyngeal insufficiency.

  1. [Current standards of abdominal wall closure techniques : Conventional suture techniques].

    PubMed

    Heger, P; Pianka, F; Diener, M K; Mihaljevic, A L

    2016-09-01

    The most frequent complications following midline abdominal laparotomy include incisional hernias, which develop in 10-15 % of patients and surgical site infections in 15-25 % of cases; however, the risk of these complications can be reduced by the surgical technique and the use of special suture materials. In 2010, the INLINE meta-analysis performed by the Study Centre of the German Society of Surgery (SDGC) revealed that a continuous suture technique using slowly absorbable suture material resulted in the lowest risk of developing postoperative incisional hernia after elective midline laparotomy. The aim of this study was to perform a systematic literature search to identify all randomized controlled trials (RCTs) that have been published since 2010 concerning conventional abdominal wall closure in order to update the 2010 INLINE meta-analysis and summarize current evidence. On 28 January 2016, a systematic literature search was performed in MEDLINE and the Cochrane Central Register of Controlled Trials (CENTRAL). All RCTs dealing with abdominal wall closure after midline laparotomy were identified and included for further analysis. Since 2010 a total of 9 RCTs comparing different techniques of abdominal wall closure have been published. Three monocentric RCTs comparing different suture materials, showed no significant differences to the INLINE meta-analysis regarding incisional hernia development; therefore, slowly absorbable sutures using a continuous suture technique are still recommended for abdominal wall closure in elective cases. Furthermore, six RCTs were identified which investigated antimicrobial suture materials but failed to show an overall advantage for Triclosan-coated suture material with respect to surgical site infections. Current evidence shows that slowly absorbable monofilament suture material using a continuous suture technique provides the best results with regard to incisional hernia rates after elective midline laparotomy. Triclosan

  2. Landing techniques in beach volleyball.

    PubMed

    Tilp, Markus; Rindler, Michael

    2013-01-01

    The aims of the present study were to establish a detailed and representative record of landing techniques (two-, left-, and right-footed landings) in professional beach volleyball and compare the data with those of indoor volleyball. Beach volleyball data was retrieved from videos taken at FIVB World Tour tournaments. Landing techniques were compared in the different beach and indoor volleyball skills serve, set, attack, and block with regard to sex, playing technique, and court position. Significant differences were observed between men and women in landings following block actions (χ(2)(2) = 18.19, p < 0.01) but not following serve, set, and attack actions. Following blocking, men landed more often on one foot than women. Further differences in landings following serve and attack with regard to playing technique and position were mainly observed in men. The comparison with landing techniques in indoor volleyball revealed overall differences both in men (χ(2)(2) = 161.4, p < 0.01) and women (χ(2)(2) = 84.91, p < 0.01). Beach volleyball players land more often on both feet than indoor volleyball players. Besides the softer surface in beach volleyball, and therefore resulting lower loads, these results might be another reason for fewer injuries and overuse conditions compared to indoor volleyball. Key PointsAbout 1/3 of all jumping actions in beach volleyball result in a landing on one foot.Especially following block situations men land on one foot more often than women.Landing techniques are related to different techniques and positions.Landings on one foot are less common in beach volleyball than indoor volleyball. This could be a reason for fewer injuries and overuse conditions.

  3. Landing Techniques in Beach Volleyball

    PubMed Central

    Tilp, Markus; Rindler, Michael

    2013-01-01

    The aims of the present study were to establish a detailed and representative record of landing techniques (two-, left-, and right-footed landings) in professional beach volleyball and compare the data with those of indoor volleyball. Beach volleyball data was retrieved from videos taken at FIVB World Tour tournaments. Landing techniques were compared in the different beach and indoor volleyball skills serve, set, attack, and block with regard to sex, playing technique, and court position. Significant differences were observed between men and women in landings following block actions (χ2(2) = 18.19, p < 0.01) but not following serve, set, and attack actions. Following blocking, men landed more often on one foot than women. Further differences in landings following serve and attack with regard to playing technique and position were mainly observed in men. The comparison with landing techniques in indoor volleyball revealed overall differences both in men (χ2(2) = 161.4, p < 0.01) and women (χ2(2) = 84.91, p < 0.01). Beach volleyball players land more often on both feet than indoor volleyball players. Besides the softer surface in beach volleyball, and therefore resulting lower loads, these results might be another reason for fewer injuries and overuse conditions compared to indoor volleyball. Key Points About 1/3 of all jumping actions in beach volleyball result in a landing on one foot. Especially following block situations men land on one foot more often than women. Landing techniques are related to different techniques and positions. Landings on one foot are less common in beach volleyball than indoor volleyball. This could be a reason for fewer injuries and overuse conditions. PMID:24149150

  4. Applications of Electromigration Techniques: Electromigration Techniques in Detection of Microorganisms

    NASA Astrophysics Data System (ADS)

    Dziubakiewicz, Ewelina; Buszewski, Bogusław

    The detection and identification of microbes is a challenge and an important aspect in many fields of our lives from medicine to bioterrorism defense. However, the analysis of such complex molecules brings a lot of questions mainly about their behavior. Bacteria are biocolloid, whose surface charge originates from the ionization of carboxyl, phosphate, or amino groups and the adsorption of ions from solution. Consequently, the charged cell wall groups determine the spontaneous formation of the electrical double layer. In this chapter application of electromigration techniques for microorganism's identification and separation are described. This approach represents the possibility to apply electromigration techniques in medical diagnosis, detection of food contamination, and sterility testing.

  5. The imbrication technique: an alternative to the sliding leaflet technique.

    PubMed

    Hashim, Peter W; Assi, Roland; Hashim, Sabet W

    2014-09-01

    Systolic anterior motion (SAM) represents a common and troublesome complication of mitral valve repair. The prevention of SAM has traditionally been based on the sliding leaflet technique, which involves resection of posterior leaflet tissue. However, this approach has not been universally adopted owing to its technical difficulty and inconsistent efficacy. We present an imbrication technique that avoids additional leaflet resection and achieves a reliable prevention of SAM. The approach has been successfully implemented in the treatment of 124 consecutive patients at high risk for SAM. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  6. Modelling of the radial forging process of a hollow billet with the mandrel on the lever radial forging machine

    NASA Astrophysics Data System (ADS)

    Karamyshev, A. P.; Nekrasov, I. I.; Pugin, A. I.; Fedulov, A. A.

    2016-04-01

    The finite-element method (FEM) has been used in scientific research of forming technological process modelling. Among the others, the process of the multistage radial forging of hollow billets has been modelled. The model includes both the thermal problem, concerning preliminary heating of the billet taking into account thermal expansion, and the deformation problem, when the billet is forged in a special machine. The latter part of the model describes such features of the process as die calibration, die movement, initial die temperature, friction conditions, etc. The results obtained can be used to define the necessary process parameters and die calibration.

  7. Authentication techniques for smart cards

    SciTech Connect

    Nelson, R.A.

    1994-02-01

    Smart card systems are most cost efficient when implemented as a distributed system, which is a system without central host interaction or a local database of card numbers for verifying transaction approval. A distributed system, as such, presents special card and user authentication problems. Fortunately, smart cards offer processing capabilities that provide solutions to authentication problems, provided the system is designed with proper data integrity measures. Smart card systems maintain data integrity through a security design that controls data sources and limits data changes. A good security design is usually a result of a system analysis that provides a thorough understanding of the application needs. Once designers understand the application, they may specify authentication techniques that mitigate the risk of system compromise or failure. Current authentication techniques include cryptography, passwords, challenge/response protocols, and biometrics. The security design includes these techniques to help prevent counterfeit cards, unauthorized use, or information compromise. This paper discusses card authentication and user identity techniques that enhance security for microprocessor card systems. It also describes the analysis process used for determining proper authentication techniques for a system.

  8. Review of uranium bioassay techniques

    SciTech Connect

    Bogard, J.S.

    1996-04-01

    A variety of analytical techniques is available for evaluating uranium in excreta and tissues at levels appropriate for occupational exposure control and evaluation. A few (fluorometry, kinetic phosphorescence analysis, {alpha}-particle spectrometry, neutron irradiation techniques, and inductively-coupled plasma mass spectrometry) have also been demonstrated as capable of determining uranium in these materials at levels comparable to those which occur naturally. Sample preparation requirements and isotopic sensitivities vary widely among these techniques and should be considered carefully when choosing a method. This report discusses analytical techniques used for evaluating uranium in biological matrices (primarily urine) and limits of detection reported in the literature. No cost comparison is attempted, although references are cited which address cost. Techniques discussed include: {alpha}-particle spectrometry; liquid scintillation spectrometry, fluorometry, phosphorometry, neutron activation analysis, fission-track counting, UV-visible absorption spectrophotometry, resonance ionization mass spectrometry, and inductively-coupled plasma mass spectrometry. A summary table of reported limits of detection and of the more important experimental conditions associated with these reported limits is also provided.

  9. Cane Technique: Modifying the Touch Technique for Full Path Coverage

    ERIC Educational Resources Information Center

    Uslan, Mark M.

    1978-01-01

    Measurements of height of cane hand, cane length, step size, and forearm length of 17 cane using blind (14-21 years old) Ss were taken for the purpose of testing the hypothesis that the touch technique does not provide 100 percent path coverage. (Author)

  10. Aseptic technique for cell culture.

    PubMed

    Coté, R J

    2001-05-01

    This unit describes some of the ways that a laboratory can deal with the constant threat of microbial contamination in cell cultures. A protocol on aseptic technique is described first. This catch-all term universally appears in any set of instructions pertaining to procedures in which noncontaminating conditions must be maintained. In reality, aseptic technique encompasses all aspects of environmental control, personal hygiene, equipment and media sterilization, and associated quality control procedures needed to ensure that a procedure is, indeed, performed with aseptic, noncontaminating technique. Although cell culture can theoretically be carried out on an open bench in a low-traffic area, most cell culture work is carried out using a horizontal laminar-flow clean bench or a vertical laminar-flow biosafety cabinet. Both are described here.

  11. NASA standard: Trend analysis techniques

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Descriptive and analytical techniques for NASA trend analysis applications are presented in this standard. Trend analysis is applicable in all organizational elements of NASA connected with, or supporting, developmental/operational programs. This document should be consulted for any data analysis activity requiring the identification or interpretation of trends. Trend analysis is neither a precise term nor a circumscribed methodology: it generally connotes quantitative analysis of time-series data. For NASA activities, the appropriate and applicable techniques include descriptive and graphical statistics, and the fitting or modeling of data by linear, quadratic, and exponential models. Usually, but not always, the data is time-series in nature. Concepts such as autocorrelation and techniques such as Box-Jenkins time-series analysis would only rarely apply and are not included in this document. The basic ideas needed for qualitative and quantitative assessment of trends along with relevant examples are presented.

  12. Evaluation of standard watermarking techniques

    NASA Astrophysics Data System (ADS)

    Marini, Enrico; Autrusseau, Florent; Le Callet, Patrick; Campisi, Patrizio

    2007-02-01

    In the last decade digital watermarking techniques have been devised to answer the ever-growing need to protect the intellectual property of digital still images, video sequences or audio from piracy attacks. Because of the proliferation of watermarking algorithms and their applications some benchmarks have been created in order to help watermarkers comparing their algorithms in terms of robustness against various attacks (i.e. Stirmark, Checkmark). However, no equal attention has been devoted to the proposition of benchmarks tailored to assess the watermark perceptual transparency. In this work, we study several watermarking techniques in terms of the mark invisibility through subjective experiments. Moreover, we test the ability of several objective metrics, used in the literature mainly to evaluate distortions due to the coding process, to be correlated with subjective scores. The conclusions drawn in the paper are supported by extensive experimentations using both several watermarking techniques and objective metrics.

  13. Post removal techniques part 1.

    PubMed

    Dickie, Jamie; McCrosson, John

    2014-01-01

    Dismantling restorations from teeth which require endodontic re-treatment can be difficult. Many dentists are reluctant to remove posts through fear of weakening, perforating or fracturing the remaining root structure. A variety of techniques have been described and developed for post removal. This is the first in a series of two papers which provide an overview of these techniques.The rationale for endodontic re-treatment, pre-operative assessment and factors affecting post removal are discussed. Techniques are illustrated with clinical case reports. The second paper describes the use of specific post removal devices and the removal of fibre posts. Endodontic re-treatment has a more successful long-term outcome than surgical treatment for failed root canal treatment. This may involve the removal of existing post restorations or portions thereof.

  14. A computational hyperspectral imaging technique

    NASA Astrophysics Data System (ADS)

    Habibi, Nasim; Azari, Mohammad; Abolbashari, Mehrdad; Farahi, Faramarz

    2016-03-01

    A novel spectral imaging technique is introduced based on a highly dispersive imaging lens system. The chromatic aberration of the lens system is utilized to spread the spectral content of the object over a focal distance. Two three-dimensional surface reconstruction algorithms, depth from focus and depth from defocus, are applied to images captured by dispersive lens system. Using these algorithms, the spectral imager is able to relate either the location of focused image or the amount of defocus at the imaging detector to the spectral content of the object. A spectral imager with ~5 nm spectral resolution is designed based on this technique. The spectral and spatial resolutions of the introduced technique are independent and can be improved simultaneously. Simulation and experimental results are presented.

  15. Resolution enhancement techniques in microscopy

    NASA Astrophysics Data System (ADS)

    Cremer, Christoph; Masters, Barry R.

    2013-05-01

    We survey the history of resolution enhancement techniques in microscopy and their impact on current research in biomedicine. Often these techniques are labeled superresolution, or enhanced resolution microscopy, or light-optical nanoscopy. First, we introduce the development of diffraction theory in its relation to enhanced resolution; then we explore the foundations of resolution as expounded by the astronomers and the physicists and describe the conditions for which they apply. Then we elucidate Ernst Abbe's theory of optical formation in the microscope, and its experimental verification and dissemination to the world wide microscope communities. Second, we describe and compare the early techniques that can enhance the resolution of the microscope. Third, we present the historical development of various techniques that substantially enhance the optical resolution of the light microscope. These enhanced resolution techniques in their modern form constitute an active area of research with seminal applications in biology and medicine. Our historical survey of the field of resolution enhancement uncovers many examples of reinvention, rediscovery, and independent invention and development of similar proposals, concepts, techniques, and instruments. Attribution of credit is therefore confounded by the fact that for understandable reasons authors stress the achievements from their own research groups and sometimes obfuscate their contributions and the prior art of others. In some cases, attribution of credit is also made more complex by the fact that long term developments are difficult to allocate to a specific individual because of the many mutual connections often existing between sometimes fiercely competing, sometimes strongly collaborating groups. Since applications in biology and medicine have been a major driving force in the development of resolution enhancing approaches, we focus on the contribution of enhanced resolution to these fields.

  16. Ultrasonic techniques for monitoring texture

    NASA Astrophysics Data System (ADS)

    Thompson, R. B.; Li, Yan

    Ultrasonic techniques are discussed for monitoring the texture (preferred crystallographic orientation) of polycrystalline aggregates. The basic principles, involving the measurement of velocity anisotropies and the relationship of these to the coefficients appearing in an expansion of the crystallite orientation distribution function, are first presented. This is followed by a discussion of three applications, including the prediction of sheet metal formability parameters in cubic metals, the characterization of hexagonal metals and the study of deformation induced textures in heavily-deformed, metal-metal composites. Included is a discussion of the role of ultrasonic techniques with respect to X-ray diffraction.

  17. Environmental monitoring using optical techniques

    NASA Astrophysics Data System (ADS)

    Svanberg, Sune

    2003-11-01

    An overview of optical techniques for environmental monitoring is presented. Range-resolved measurements of atmospheric pollutants can be performed using the differential absorption lidar technique. Fluorescence lidar allows assessment of vegetation status and also the conditions of the facades of historical buildings. Diode lasers provide particularly realistic schemes for atmospheric gas analysis, where certain wavelength ranges, which are not easily directly assessed, can be reached by sum- and difference frequency generation. Finally, the gas correlation principle can be used for real-time imaging of hydrocarbons. Several types of such optical environmental monitoring are illustrated with examples from research at the Lund Institute of Technology, Sweden.

  18. Techniques and indications in radiology

    SciTech Connect

    Lange, S.

    1987-01-01

    The stated purpose of this book is to review modern radiologic diagnostic techniques as applied to the study of the kidney and urinary tract, and their pertinent indications. This goal is partially accomplished in the first two segments of the book, which consist of about 100 pages. These include a synoptic description of various techniques - including classic uroradiologic studies such as excretory urography and retrograde pyelography, plus sonography, computed tomography, angiography, and nuclear medicine. The diagnostic signs and the differential diagnoses are fairly well described, aided by a profusion of tables and diagrams. The overall quality of the reproduction of the illustrations is good.

  19. Selected photographic techniques, a compilation

    NASA Technical Reports Server (NTRS)

    1971-01-01

    A selection has been made of methods, devices, and techniques developed in the field of photography during implementation of space and nuclear research projects. These items include many adaptations, variations, and modifications to standard hardware and practice, and should prove interesting to both amateur and professional photographers and photographic technicians. This compilation is divided into two sections. The first section presents techniques and devices that have been found useful in making photolab work simpler, more productive, and higher in quality. Section two deals with modifications to and special applications for existing photographic equipment.

  20. Urologic imaging and interventional techniques

    SciTech Connect

    Bush, W.H.

    1989-01-01

    This book provides an overview of all imaging modalities and invasive techniques of the genitourinary system. Three general chapters discuss ionic and nonionic contrast media, the management of reactions to contrast media, and radiation doses from various uroradiologic procedures. Chapters are devoted to intravenous pyelography, computed tomography, magnetic resonance imaging, ultrasound, nuclear medicine, lymphography, arteriography, and venography. Two chapters discuss the pediatric applications of uroradiology and ultrasound. Two chapters integrate the various imaging techniques of the upper and lower genitourinary systems into an algorithmic approach for various pathologic entities.

  1. Endoscopic ultrasonography: equipment and technique.

    PubMed

    Röesch, Thomas

    2005-01-01

    By definition, endoscopic ultrasonography (EUS) combines endoscopy and high-frequency ultrasound, incorporating a small ultrasonic transducer into the tip of endoscopes. For the upper gastrointestinal tract, mostly oblique-viewing endoscopes are used, although recently, forward viewing instruments have become available. For colorectal EUS, rigid probes for the rectum and a flexible forward-viewing echocolonoscope are available. EUS generates ultrasound either mechanically or electronically, depending on the type of instrument used. The electronic technique potentially allows the incorporation of (color) Doppler ultrasound, which allows for additional processing and postprocessing functions. This generally is considered the EUS technique of the future.

  2. Grid flexibility and patching techniques

    NASA Technical Reports Server (NTRS)

    Keith, T. G.; Smith, L. W.; Yung, C. N.; Barthelson, S. H.; Dewitt, K. J.

    1984-01-01

    The numerical determination of combustor flowfields is of great value to the combustor designer. An a priori knowledge of the flow behavior can speed the combustor design process and reduce the number of experimental test rigs required to arrive at an optimal design. Even 2-D steady incompressible isothermal flow predictions are of use; many codes of this kind are available, each employing different techniques to surmount the difficulties arising from the nonlinearity of the governing equations and from typically irregular combustor geometries. Mapping techniques (algebraic and elliptic PDE), and adaptive grid methods (both multi-grid and grid embedding) as applied to axisymmetric combustors are discussed.

  3. Current techniques in laparoscopic appendectomy.

    PubMed

    Nowzaradan, Y; Barnes, J P

    1993-12-01

    An improved technique for laparoscopic appendectomy based on an experience of > 120 cases is presented. This method includes numerous additions to and modifications of previously described techniques and is effective for gangrenous and perforated appendicitis as well as for less severe cases. The most important elements are that (a) it is a safer procedure for attaining insertion of the Veress needle and the primary trocar; (b) it employs electrocautery to separate the appendix from the mesoappendix; (c) an Endosac can be used for removal of the appendix from the abdomen without contamination of the abdominal wall; (d) no laser is necessary; and (e) staples are rarely necessary.

  4. Radiotherapy technique for thyroid cancer

    SciTech Connect

    Thambi, V.; Pedapatti, P.J.; Murthy, A.; Kartha, P.K.

    1980-02-01

    A treatment technique for treating patients with cancer of the thyroid is presented. This is a modification of the bar-arc technique that uses a centrally blocked moving field. We have introduced wedges and partial midline block to achieve uniform dose within the treatment volume. This enables the desired dose to be delivered to the primary, the lymph nodes and the cervical soft tissues at risk, yet keeping the dose to the spinal cord to a minimum in the cervical region and to acceptable levels in the superior mediastinum.

  5. Techniques in Endovascular Aneurysm Repair

    PubMed Central

    Phade, Sachin V.; Garcia-Toca, Manuel; Kibbe, Melina R.

    2011-01-01

    Endovascular repair of infrarenal abdominal aortic aneurysms (EVARs) has revolutionized the treatment of aortic aneurysms, with over half of elective abdominal aortic aneurysm repairs performed endoluminally each year. Since the first endografts were placed two decades ago, many changes have been made in graft design, operative technique, and management of complications. This paper summarizes modern endovascular grafts, considerations in preoperative planning, and EVAR techniques. Specific areas that are addressed include endograft selection, arterial access, sheath delivery, aortic branch management, graft deployment, intravascular ultrasonography, pressure sensors, management of endoleaks and compressed limbs, and exit strategies. PMID:22121487

  6. Mass spectrometry. [review of techniques

    NASA Technical Reports Server (NTRS)

    Burlingame, A. L.; Kimble, B. J.; Derrick, P. J.

    1976-01-01

    Advances in mass spectrometry (MS) and its applications over the past decade are reviewed in depth, with annotated literature references. New instrumentation and techniques surveyed include: modulated-beam MS, chromatographic MS on-line computer techniques, digital computer-compatible quadrupole MS, selected ion monitoring (mass fragmentography), and computer-aided management of MS data and interpretation. Areas of application surveyed include: organic MS and electron impact MS, field ionization kinetics, appearance potentials, translational energy release, studies of metastable species, photoionization, calculations of molecular orbitals, chemical kinetics, field desorption MS, high pressure MS, ion cyclotron resonance, biochemistry, medical/clinical chemistry, pharmacology, and environmental chemistry and pollution studies.

  7. Techniques for Interfacing Multiplex Systems.

    DTIC Science & Technology

    1981-02-01

    Study 6 1.2. 3 Selection of Techniques 7 1.3 RECOMMENDATIONS AND SUMMARY 7 1.3.1 ARINC and H009 (F-15) Interfaces 7 1. 3. 2 Basic Signal...Override Transmitter Shutdown 72 3.4.8 Selected Transmitter Shutdown 72 viii TABLE OF CONTENTS (cont t d) Page I 3.4.9 Override Selected Transmitter...Common Mode Rejection 90 4.0 SELECTION OF TECHNIQUES 91 4.1 BACKGROUND AND RATIONALE 91 4.1.1 Ease of Retrofit 91 4. 1. 2 Future Implementation 92 4

  8. Mass spectrometry. [review of techniques

    NASA Technical Reports Server (NTRS)

    Burlingame, A. L.; Kimble, B. J.; Derrick, P. J.

    1976-01-01

    Advances in mass spectrometry (MS) and its applications over the past decade are reviewed in depth, with annotated literature references. New instrumentation and techniques surveyed include: modulated-beam MS, chromatographic MS on-line computer techniques, digital computer-compatible quadrupole MS, selected ion monitoring (mass fragmentography), and computer-aided management of MS data and interpretation. Areas of application surveyed include: organic MS and electron impact MS, field ionization kinetics, appearance potentials, translational energy release, studies of metastable species, photoionization, calculations of molecular orbitals, chemical kinetics, field desorption MS, high pressure MS, ion cyclotron resonance, biochemistry, medical/clinical chemistry, pharmacology, and environmental chemistry and pollution studies.

  9. Selenium incorporation using recombinant techniques

    SciTech Connect

    Walden, Helen

    2010-04-01

    An overview of techniques for recombinant incorporation of selenium and subsequent purification and crystallization of the resulting labelled protein. Using selenomethionine to phase macromolecular structures is common practice in structure determination, along with the use of selenocysteine. Selenium is consequently the most commonly used heavy atom for MAD. In addition to the well established recombinant techniques for the incorporation of selenium in prokaryal expression systems, there have been recent advances in selenium labelling in eukaryal expression, which will be discussed. Tips and things to consider for the purification and crystallization of seleno-labelled proteins are also included.

  10. Drilling techniques for osteochondritis dissecans.

    PubMed

    Heyworth, Benton E; Edmonds, Eric W; Murnaghan, M Lucas; Kocher, Mininder S

    2014-04-01

    Although the advanced stages of osteochondritis dissecans remain challenging to treat, most early-stage lesions in skeletally immature patients, if managed appropriately, can be stimulated to heal. For stable lesions that do not demonstrate adequate healing with nonoperative measures, such as activity modification, weight-bearing protection, or bracing, drilling of the subchondral bone has emerged as the gold standard of management. Several techniques of drilling exist, including transarticular drilling, retroarticular drilling, and notch drilling. Although each technique has been shown to be effective in small retrospective studies, higher-powered prospective comparative studies are needed to better elucidate their relative advantages and disadvantages.

  11. Computerized proof techniques for undergraduates

    NASA Astrophysics Data System (ADS)

    Smith, Christopher J.; Tefera, Akalu; Zeleke, Aklilu

    2012-12-01

    The use of computer algebra systems such as Maple and Mathematica is becoming increasingly important and widespread in mathematics learning, teaching and research. In this article, we present computerized proof techniques of Gosper, Wilf-Zeilberger and Zeilberger that can be used for enhancing the teaching and learning of topics in discrete mathematics. We demonstrate by examples how one can use these computerized proof techniques to raise students' interests in the discovery and proof of mathematical identities and enhance their problem-solving skills.

  12. EDITORIAL: Imaging Systems and Techniques Imaging Systems and Techniques

    NASA Astrophysics Data System (ADS)

    Giakos, George; Yang, Wuqiang; Petrou, M.; Nikita, K. S.; Pastorino, M.; Amanatiadis, A.; Zentai, G.

    2011-10-01

    This special feature on Imaging Systems and Techniques comprises 27 technical papers, covering essential facets in imaging systems and techniques both in theory and applications, from research groups spanning three different continents. It mainly contains peer-reviewed articles from the IEEE International Conference on Imaging Systems and Techniques (IST 2011), held in Thessaloniki, Greece, as well a number of articles relevant to the scope of this issue. The multifaceted field of imaging requires drastic adaptation to the rapid changes in our society, economy, environment, and the technological revolution; there is an urgent need to address and propose dynamic and innovative solutions to problems that tend to be either complex and static or rapidly evolving with a lot of unknowns. For instance, exploration of the engineering and physical principles of new imaging systems and techniques for medical applications, remote sensing, monitoring of space resources and enhanced awareness, exploration and management of natural resources, and environmental monitoring, are some of the areas that need to be addressed with urgency. Similarly, the development of efficient medical imaging techniques capable of providing physiological information at the molecular level is another important area of research. Advanced metabolic and functional imaging techniques, operating on multiple physical principles, using high resolution and high selectivity nanoimaging techniques, can play an important role in the diagnosis and treatment of cancer, as well as provide efficient drug-delivery imaging solutions for disease treatment with increased sensitivity and specificity. On the other hand, technical advances in the development of efficient digital imaging systems and techniques and tomographic devices operating on electric impedance tomography, computed tomography, single-photon emission and positron emission tomography detection principles are anticipated to have a significant impact on a

  13. Spatial interpolation techniques using R

    EPA Science Inventory

    Interpolation techniques are used to predict the cell values of a raster based on sample data points. For example, interpolation can be used to predict the distribution of sediment particle size throughout an estuary based on discrete sediment samples. We demonstrate some inter...

  14. Spatial interpolation techniques using R

    EPA Science Inventory

    Interpolation techniques are used to predict the cell values of a raster based on sample data points. For example, interpolation can be used to predict the distribution of sediment particle size throughout an estuary based on discrete sediment samples. We demonstrate some inter...

  15. Single-Donor Leukophoretic Technique

    NASA Technical Reports Server (NTRS)

    Eberhardt, R. N.

    1977-01-01

    Leukocyte separation-and-retrieval device utilizes granulocyte and monocyte property of leukoadhesion to glass surfaces as basis of their separation from whole blood. Device is used with single donor technique and has application in biological and chemical processing, veterinary research and clinical care.

  16. Techniques Class: September 12, 2001.

    ERIC Educational Resources Information Center

    More, William; Corsetti, Patricia L.; Endleman, Orna; Julian, Sarah; Lindemann, Evie; Spinelli, Laura

    2002-01-01

    On September 12, 2001, the Techniques in Art Therapy class in the art therapy program at Albertus Magnus College met at its normal Wednesday evening time. This article describes the class session through the words and images of several class members who found the class useful in their own process of beginning to deal with the attacks and their…

  17. Probabilistic Techniques for Phrase Extraction.

    ERIC Educational Resources Information Center

    Feng, Fangfang; Croft, W. Bruce

    2001-01-01

    This study proposes a probabilistic model for automatically extracting English noun phrases for indexing or information retrieval. The technique is based on a Markov model, whose initial parameters are estimated by a phrase lookup program with a phrase dictionary, then optimized by a set of maximum entropy parameters. (Author/LRW)

  18. Objective techniques for psychological assessment

    NASA Technical Reports Server (NTRS)

    Wortz, E.; Hendrickson, W.; Ross, T.

    1973-01-01

    A literature review and a pilot study are used to develop psychological assessment techniques for determining objectively the major aspects of the psychological state of an astronaut. Relationships between various performance and psychophysiological variables and between those aspects of attention necessary to engage successfully in various functions are considered in developing a paradigm to be used for collecting data in manned isolation chamber experiments.

  19. Counselling Techniques for Outdoor Leaders.

    ERIC Educational Resources Information Center

    Chase, Michelle; Chase, Robert

    1992-01-01

    Outdoor leaders need counseling skills to deal with interpersonal conflicts that arise within a group and to facilitate participant growth and change. Person-centered counseling, reality therapy counseling, and behavioral counseling are discussed, as well as how various techniques from each can be used to the benefit of the leader and the group.…

  20. Techniques for hot structures testing

    NASA Technical Reports Server (NTRS)

    Deangelis, V. Michael; Fields, Roger A.

    1990-01-01

    Hot structures testing have been going on since the early 1960's beginning with the Mach 6, X-15 airplane. Early hot structures test programs at NASA-Ames-Dryden focused on operational testing required to support the X-15 flight test program, and early hot structures research projects focused on developing lab test techniques to simulate flight thermal profiles. More recent efforts involved numerous large and small hot structures test programs that served to develop test methods and measurement techniques to provide data that promoted the correlation of test data with results from analytical codes. In Nov. 1988 a workshop was sponsored that focused on the correlation of hot structures test data with analysis. Limited material is drawn from the workshop and a more formal documentation is provided of topics that focus on hot structures test techniques used at NASA-Ames-Dryden. Topics covered include the data acquisition and control of testing, the quartz lamp heater systems, current strain and temperature sensors, and hot structures test techniques used to simulate the flight thermal environment in the lab.

  1. Techniques for assessing extramarket values

    Treesearch

    Donald F. Dennis

    1995-01-01

    Central to effective policy development and management of natural resources is an understanding of the trade-offs stakeholders are willing to accept and the values they hold. Although market prices reflect society's preferences to some degree, they clearly do not encompass all values or costs. Conjoint techniques offer a means to estimate and analyze stakeholder...

  2. Caudal septum surgery techniques reviewed.

    PubMed

    Cobo, Roxana; Caldas, Angie

    2017-02-01

    The caudal septum has important functional and aesthetic implications. Deviations in this area can result in important nasal obstruction due not only to blockage of the nasal passage but also to compromise of the internal nasal valve. Cosmetically, alterations in the caudal septum can result in a twisted nasal tip, loss of projection, rotation, and imbalance in the ala-columellar relationship. Contemporary surgical options will be discussed showing how to preserve, reshape, and reinforce the caudal septum to obtain a final looking nose that is not only functional but also aesthetically pleasing. Recent publications have shown that cartilage preservation and remodeling techniques can be efficient in the treatment of the caudal septum. Adequate preoperative diagnosis must be made to be able to create a step-wise approach evolving from simple suturing techniques to more complex ones that require the use of grafts to reposition and keep the caudal septum in the midline with an adequate functional and cosmetic outcome. Adequate management of the caudal portion of the nasal septum is a challenge because of its importance in nasal function and cosmetic final results. There are many surgical options that can be used to correct and align this structure and there is no one single surgical technique that can be used in all cases. A step-wise approach is presented covering the different techniques used today evolving from simple to more complicated ones. The final surgical objective should be cosmetically pleasing noses that function appropriately.

  3. The ancient technique of "gastrorrhaphy".

    PubMed

    Papavramidou, Niki; Christopoulou-Aletra, Helen

    2009-07-01

    The paper describes "gastrorrhaphy," deriving from the Greek words "gastir" meaning "abdomen" and "rhaphy" meaning "suturing," which was a technique used for the treatment of abdominal wounds. The technique is described in detail in the texts of Celsus (first century A.D.) and in those of Galen (second century A.D.). Furthermore, references were found in Oribasius' texts (fourth century A.D.) and in the writings of two veterinarian doctors of the same period. We provide our drawings in order to elucidate the different techniques of suturing. Celsus described one method of "gastrorrhaphy" while Galen presented two different methods for this procedure. All three methods agree on the processes required: replacement of the prolapsed viscera, cleaning of the wound, and suturing. The difference in methods is in the way of suturing the wound; Celsus suggests stitches in layers. While Galen's first method refers to stitching of the peritoneum with the abdominal wall, his second method refers to stitching of similar structures, meaning peritoneum to peritoneum and abdominal wall to abdominal wall. Celsus' method strongly resembles stitching in layers with cross-sutures, while both of the Galenic techniques of gastrorrhaphy are versions of the full-thickness sutures used nowadays. It should be stressed out that Galen's methods of "gastrorrhaphy" were used by Andreas Vesalius and Ambroise Paré many centuries later.

  4. Teaching Techniques in Clinical Chemistry.

    ERIC Educational Resources Information Center

    Wilson, Diane

    This master's thesis presents several instructional methods and techniques developed for each of eleven topics or subject areas in clinical chemistry: carbohydrate metabolism, lipid metabolism, diagnostic enzymology, endocrinology, toxicology, quality control, electrolytes, acid base balance, hepatic function, nonprotein nitrogenous compounds, and…

  5. The Split-Stem Technique

    ERIC Educational Resources Information Center

    Carter, Roy A.

    1972-01-01

    Describes a procedure useful for investigating the effects of substances on plant growth and development. A bean seedling's stem is partially split, and each half is placed in a different nutrient solution. Suggestions for the instructional use of the technique are made. (AL)

  6. Generalized fast automatic differentiation technique

    NASA Astrophysics Data System (ADS)

    Evtushenko, Yu. G.; Zubov, V. I.

    2016-11-01

    A new efficient technique intended for the numerical solution of a broad class of optimal control problems for complicated dynamical systems described by ordinary and/or partial differential equations is investigated. In this approach, canonical formulas are derived to precisely calculate the objective function gradient for a chosen finite-dimensional approximation of the objective functional.

  7. Museum Techniques in Fundamental Education.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Paris (France).

    Some museum techniques and methods can be used in fundamental educational programs without elaborate buildings or equipment; exhibitions should be based on valid presumptions and should take into account the "common sense" beliefs of people for whom the exhibit is designed. They can be used profitably in the economic development of local…

  8. Biopsy techniques for intraocular tumors

    PubMed Central

    Rishi, Pukhraj; Dhami, Abhinav; Biswas, Jyotirmay

    2016-01-01

    Biopsy involves the surgical removal of a tissue specimen for histopathologic evaluation. Most intraocular tumors are reliably diagnosed based on the clinical evaluation or with noninvasive diagnostic techniques. However, accurately diagnosing a small percentage of tumors can be challenging. A tissue biopsy is thus needed to establish a definitive diagnosis and plan the requisite treatment. From fine-needle aspiration biopsy (FNAB) to surgical excision, all tissue collection techniques have been studied in the literature. Each technique has its indications and limitations. FNAB has been reported to provide for 88–95% reliable and safe ophthalmic tumor diagnosis and has gained popularity for prognostic purposes and providing eye conserving treatment surgeries. The technique and instrumentation for biopsy vary depending upon the tissue involved (retina, choroid, subretinal space, vitreous, and aqueous), suspected diagnosis, size, location, associated retinal detachment, and clarity of the media. The cytopathologist confers a very important role in diagnosis and their assistance plays a key role in managing and planning the treatment for malignancies. PMID:27488148

  9. Optical multiple object tracking techniques

    NASA Astrophysics Data System (ADS)

    Liu, Hua-Kuang; Chao, Tien-Hsin

    1989-02-01

    Two multichannel multiple-object tracking techniques are reviewed. In the diffraction grating technique, the input scene is picked up by a TV camera and imaged onto a liquid-crystal light valve (LCLV), and the output side of the light valve is illuminated with a suitably polarized and collimated coherent laser beam to yield a reflected beam with polarization modulated according to the intensity of the incoherent input. This reflected beam passes through a beam splitter cube and an analyzer, resulting in an intensity modulated coherent image. An array of spectrum islands containing the information of the input appears after crossing a contact screen/lens combination. In the multiple-focus hololens technique, the scene of moving objects is sent into the LCTVSLM through a camera; a collimated laser beam is incident upon the LCTV screen; a low-pass filter is inserted between the LCTVSLM and the hololens for the removal of the high order diffractions due to the grid structure of the LCTV. The feasibility of the LCTVSLM and multiple-focus hololens technique is demonstrated.

  10. Optical multiple object tracking techniques

    NASA Technical Reports Server (NTRS)

    Liu, Hua-Kuang; Chao, Tien-Hsin

    1989-01-01

    Two multichannel multiple-object tracking techniques are reviewed. In the diffraction grating technique, the input scene is picked up by a TV camera and imaged onto a liquid-crystal light valve (LCLV), and the output side of the light valve is illuminated with a suitably polarized and collimated coherent laser beam to yield a reflected beam with polarization modulated according to the intensity of the incoherent input. This reflected beam passes through a beam splitter cube and an analyzer, resulting in an intensity modulated coherent image. An array of spectrum islands containing the information of the input appears after crossing a contact screen/lens combination. In the multiple-focus hololens technique, the scene of moving objects is sent into the LCTVSLM through a camera; a collimated laser beam is incident upon the LCTV screen; a low-pass filter is inserted between the LCTVSLM and the hololens for the removal of the high order diffractions due to the grid structure of the LCTV. The feasibility of the LCTVSLM and multiple-focus hololens technique is demonstrated.

  11. A measurement technique for hydroxyacetone

    SciTech Connect

    Klotz, P.J.

    1999-10-04

    Hydroxyacetone (HA) is mainly produced in the atmosphere from oxidation of hydrocarbons of the type, CH{sub 3}(R)C{double{underscore}bond}CH{sub 2}. Tuazon and Atkinson (1990) reported HA yield of 41% from the OH-initiated oxidation of methacrolein in the presence of NOx. Since methacrolein is a major product of isoprene oxidation (Carter and Atkinson, 1996), isoprene, a key biogenic hydrocarbon, is therefore expected to be an important source for HA. Consequently, knowledge of ambient concentration of HA would provide information needed to examine the applicability of isoprene reaction mechanisms developed in laboratory and to assess the contribution of isoprene to photooxidant production. The commonly used GC-FID technique involving cryo-focusing is unsuitable for HA owing to HA's thermal instability. When subjected to a temperature of 100 C for only a few seconds, HA was found to disappear completely. Since HA is highly soluble in water, the authors developed a wet chemical technique similar in principle to the one they reported earlier, namely, derivatization following liquid scrubbing. To increase the sensitivity, they adopted a fluorescence detection scheme based on o-phthaldialdehyde (OPA) chemistry. The technique was deployed in the field during two measurement periods at a NARSTO site located on Long Island, New York. The authors report the principle and the operation of this technique and the results obtained from these field studies.

  12. Colonoscopic polypectomy and associated techniques

    PubMed Central

    Fyock, Christopher J; Draganov, Peter V

    2010-01-01

    Polypectomy of colonic polyps has been shown to reduce the risk of colon cancer development and is considered a fundamental skill for all endoscopists who perform colonoscopy. A variety of polypectomy techniques and devices are available, and their use can vary greatly based on local availability and preferences. In general, cold forceps and cold snare have been the polypectomy methods of choice for smaller polyps, and hot snare has been the method of choice for larger polyps. The use of hot forceps has mostly fallen out of favor. Polypectomy for difficult to remove polyps may require the use of special devices and advanced techniques and has continued to evolve. As a result, the vast majority of polyps today can be removed endoscopically. Since electrocautery is frequently used for polypectomy, endoscopists should be thoroughly familiar with the basic principles of electrosurgery as it pertains to polypectomy. Tattooing of a polypectomy site is an important adjunct to polypectomy and can greatly facilitate future surgery or endoscopic surveillance. The two most common post-polypectomy complications are bleeding and perforation. Their incidence can be decreased with the use of meticulous polypectomy techniques and the application of some prophylactic maneuvers. This review will examine the technique of polypectomy and its complications from the perspective of the practicing gastroenterologist. PMID:20677334

  13. Progress in Exosome Isolation Techniques

    PubMed Central

    Li, Pin; Kaslan, Melisa; Lee, Sze Han; Yao, Justin; Gao, Zhiqiang

    2017-01-01

    Exosomes are one type of membrane vesicles secreted into extracellular space by most types of cells. In addition to performing many biological functions particularly in cell-cell communication, cumulative evidence has suggested that several biological entities in exosomes like proteins and microRNAs are closely associated with the pathogenesis of most human malignancies and they may serve as invaluable biomarkers for disease diagnosis, prognosis, and therapy. This provides a commanding impetus and growing demands for simple, efficient, and affordable techniques to isolate exosomes. Capitalizing on the physicochemical and biochemical properties of exosomes, a number of techniques have been developed for the isolation of exosomes. This article summarizes the advances in exosome isolation techniques with an emphasis on their isolation mechanism, performance, challenges, and prospects. We hope that this article will provide an overview of exosome isolation techniques, opening up new perspectives towards the development more innovative strategies and devices for more time saving, cost effective, and efficient isolations of exosomes from a wide range of biological matrices. PMID:28255367

  14. Digital synchronization and communication techniques

    NASA Technical Reports Server (NTRS)

    Lindsey, William C.

    1992-01-01

    Information on digital synchronization and communication techniques is given in viewgraph form. Topics covered include phase shift keying, modems, characteristics of open loop digital synchronizers, an open loop phase and frequency estimator, and a digital receiver structure using an open loop estimator in a decision directed architecture.

  15. Thumb ultrasound: Technique and pathologies

    PubMed Central

    Singh, Jatinder P; Kumar, Shwetam; Kathiria, Atman V; Harjai, Rachit; Jawed, Akram; Gupta, Vikas

    2016-01-01

    Ultrasound is ideally suited for the assessment of complex anatomy and pathologies of the thumb. Focused and dynamic thumb ultrasound can provide a rapid real-time diagnosis and can be used for guided treatment in certain clinical situations. We present a simplified approach to scanning technique for thumb-related pathologies and illustrate a spectrum of common and uncommon pathologies encountered. PMID:27857468

  16. Computerized Proof Techniques for Undergraduates

    ERIC Educational Resources Information Center

    Smith, Christopher J.; Tefera, Akalu; Zeleke, Aklilu

    2012-01-01

    The use of computer algebra systems such as Maple and Mathematica is becoming increasingly important and widespread in mathematics learning, teaching and research. In this article, we present computerized proof techniques of Gosper, Wilf-Zeilberger and Zeilberger that can be used for enhancing the teaching and learning of topics in discrete…

  17. Uranium Detection - Technique Validation Report

    SciTech Connect

    Colletti, Lisa Michelle; Garduno, Katherine; Lujan, Elmer J.; Mechler-Hickson, Alexandra Marie; May, Iain; Reilly, Sean Douglas

    2016-04-14

    As a LANL activity for DOE/NNSA in support of SHINE Medical Technologies™ ‘Accelerator Technology’ we have been investigating the application of UV-vis spectroscopy for uranium analysis in solution. While the technique has been developed specifically for sulfate solutions, the proposed SHINE target solutions, it can be adapted to a range of different solution matrixes. The FY15 work scope incorporated technical development that would improve accuracy, specificity, linearity & range, precision & ruggedness, and comparative analysis. Significant progress was achieved throughout FY 15 addressing these technical challenges, as is summarized in this report. In addition, comparative analysis of unknown samples using the Davies-Gray titration technique highlighted the importance of controlling temperature during analysis (impacting both technique accuracy and linearity/range). To fully understand the impact of temperature, additional experimentation and data analyses were performed during FY16. The results from this FY15/FY16 work were presented in a detailed presentation, LA-UR-16-21310, and an update of this presentation is included with this short report summarizing the key findings. The technique is based on analysis of the most intense U(VI) absorbance band in the visible region of the uranium spectra in 1 M H2SO4, at λmax = 419.5 nm.

  18. New Techniques for Particle Acclerators

    SciTech Connect

    Sessler, Andrew M.

    1990-06-01

    A review is presented of the new techniques which have been proposed for use in particle accelerators. Attention is focused upon those areas where significant progress has been made in the last two years--in particular, upon two-beam accelerators, wakefield accelerators, and plasma focusers.

  19. Diagnostic cardiology: Noninvasive imaging techniques

    SciTech Connect

    Come, P.C.

    1985-01-01

    This book contains 23 chapters. Some of the chapter titles are: The chest x-ray and cardiac series; Computed tomographic scanning of the heart, coronary arteries, and great vessels; Digital subtraction angiography in the assessment of cardiovascular disease; Magnetic resonance: technique and cardiac applications; Basics of radiation physics and instrumentation; and Nuclear imaging: the assessment of cardiac performance.

  20. Single-Donor Leukophoretic Technique

    NASA Technical Reports Server (NTRS)

    Eberhardt, R. N.

    1977-01-01

    Leukocyte separation-and-retrieval device utilizes granulocyte and monocyte property of leukoadhesion to glass surfaces as basis of their separation from whole blood. Device is used with single donor technique and has application in biological and chemical processing, veterinary research and clinical care.

  1. Teaching Techniques in Clinical Chemistry.

    ERIC Educational Resources Information Center

    Wilson, Diane

    This master's thesis presents several instructional methods and techniques developed for each of eleven topics or subject areas in clinical chemistry: carbohydrate metabolism, lipid metabolism, diagnostic enzymology, endocrinology, toxicology, quality control, electrolytes, acid base balance, hepatic function, nonprotein nitrogenous compounds, and…

  2. Developments in functional neuroimaging techniques

    SciTech Connect

    Aine, C.J.

    1995-03-01

    A recent review of neuroimaging techniques indicates that new developments have primarily occurred in the area of data acquisition hardware/software technology. For example, new pulse sequences on standard clinical imagers and high-powered, rapidly oscillating magnetic field gradients used in echo planar imaging (EPI) have advanced MRI into the functional imaging arena. Significant developments in tomograph design have also been achieved for monitoring the distribution of positron-emitting radioactive tracers in the body (PET). Detector sizes, which pose a limit on spatial resolution, have become smaller (e.g., 3--5 mm wide) and a new emphasis on volumetric imaging has emerged which affords greater sensitivity for determining locations of positron annihilations and permits smaller doses to be utilized. Electromagnetic techniques have also witnessed growth in the ability to acquire data from the whole head simultaneously. EEG techniques have increased their electrode coverage (e.g., 128 channels rather than 16 or 32) and new whole-head systems are now in use for MEG. But the real challenge now is in the design and implementation of more sophisticated analyses to effectively handle the tremendous amount of physiological/anatomical data that can be acquired. Furthermore, such analyses will be necessary for integrating data across techniques in order to provide a truly comprehensive understanding of the functional organization of the human brain.

  3. Management Techniques for School Districts.

    ERIC Educational Resources Information Center

    Lane, John J., Ed.

    This volume addresses five of the critical areas of school business management: planning, organizational management, personnel management, controlling, and directing. The various chapters describe a variety of techniques and processes for getting people to perform effectively in meeting organizational goals. The first section focuses on planning…

  4. Individualized Instruction Using Computer Techniques

    ERIC Educational Resources Information Center

    Castleberry, S.; Lagowski, J. J.

    1970-01-01

    Explains how computer-based instructional techniques are being used to individualize general chemistry instruction. After describing the computer equipment and language used, author describes simulated experiments and computer programmed drill exercises. Outlines fifteen topics programmed for instruction. Comparisons were made between experimental…

  5. Brain Friendly Techniques: Mind Mapping

    ERIC Educational Resources Information Center

    Goldberg, Cristine

    2004-01-01

    Mind Mapping can be called the Swiss Army Knife for the brain, a total visual thinking tool or a multi-handed thought catcher. Invented by Tony Buzan in the early 1970s and used by millions around the world, it is a method that can be a part of a techniques repertoire when teaching information literacy, planning, presenting, thinking, and so…

  6. Rhinoplasty – indications and techniques

    PubMed Central

    Tasman, Abel-Jan

    2008-01-01

    Rhinoplasty is considered to be one of the most challenging procedures in otolaryngology head and neck surgery. Meticulous planning and excellent surgical skills are pre-requisites for reproducible good outcomes. More than 100 years after the first rhinoplasty, many controversies regarding indication and techniques remain unresolved. The aim of this article is to review current concepts and arguments. PMID:22073085

  7. Orthodontic palatal implants: clinical technique.

    PubMed

    Tinsley, D; O'Dwyer, J J; Benson, P E; Doyle, P T; Sandler, J

    2004-03-01

    The aim of this paper is to familiarize the readers with some of the clinical considerations necessary to ensure successful use of mid-palatal implants. Both surgical and technical aspects will be discussed along with a description of impression techniques used.

  8. New technique for sternal osteosynthesis.

    PubMed

    Roux, D; Fournial, G; Glock, Y; Nottin, R

    1995-10-01

    In our department, we have developed a new method for sternal osteosynthesis. This technique uses steel threads and a sternal retractor. The removable valves are removed and placed with a two-pulley device, which allows good osteosynthesis without assistance or effort.

  9. Compendium on Risk Analysis Techniques

    DTIC Science & Technology

    The evolution of risk analysis in the materiel acquisition process is traced from the Secretary Packard memorandum to current AMC guidance. Risk ... analysis is defined and many of the existing techniques are described in light of this definition and their specific role in program management and

  10. Survey of Biochemical Separation Techniques

    ERIC Educational Resources Information Center

    Nilsson, Melanie R.

    2007-01-01

    A simple laboratory exercise is illustrated that exposes students to wide range of separation techniques in one laboratory program and provides a nice complement to a project-oriented program. Students have learned the basic principles of syringe filtration, centricon, dialysis, gel filtration and solid-phase extraction methodologies and have got…

  11. Multimodal Revision Techniques in Webtexts

    ERIC Educational Resources Information Center

    Ball, Cheryl E.

    2014-01-01

    This article examines how an online scholarly journal, "Kairos: Rhetoric, Technology, Pedagogy," mentors authors to revise their webtexts (interactive, digital media scholarship) for publication. Using an editorial pedagogy in which multimodal and rhetorical genre theories are merged with revision techniques found in process-based…

  12. Computerized Proof Techniques for Undergraduates

    ERIC Educational Resources Information Center

    Smith, Christopher J.; Tefera, Akalu; Zeleke, Aklilu

    2012-01-01

    The use of computer algebra systems such as Maple and Mathematica is becoming increasingly important and widespread in mathematics learning, teaching and research. In this article, we present computerized proof techniques of Gosper, Wilf-Zeilberger and Zeilberger that can be used for enhancing the teaching and learning of topics in discrete…

  13. The Split-Stem Technique

    ERIC Educational Resources Information Center

    Carter, Roy A.

    1972-01-01

    Describes a procedure useful for investigating the effects of substances on plant growth and development. A bean seedling's stem is partially split, and each half is placed in a different nutrient solution. Suggestions for the instructional use of the technique are made. (AL)

  14. Time domain period determination techniques

    NASA Technical Reports Server (NTRS)

    Stellingwerf, R. F.

    1980-01-01

    Two simple period determination schemes are discussed. They are well suited to problems involving non-sinusoidal periodic phenomena sampled at a few irregularly spaced points. Statistical properties are discussed. The techniques are applied to the double mode Cepheids BK Cen and TU Cas as test cases.

  15. Parallel pseudospectral domain decomposition techniques

    NASA Technical Reports Server (NTRS)

    Gottlieb, David; Hirsh, Richard S.

    1988-01-01

    The influence of interface boundary conditions on the ability to parallelize pseudospectral multidomain algorithms is investigated. Using the properties of spectral expansions, a novel parallel two domain procedure is generalized to an arbitrary number of domains each of which can be solved on a separate processor. This interface boundary condition considerably simplifies influence matrix techniques.

  16. Parallel pseudospectral domain decomposition techniques

    NASA Technical Reports Server (NTRS)

    Gottlieb, David; Hirsch, Richard S.

    1989-01-01

    The influence of interface boundary conditions on the ability to parallelize pseudospectral multidomain algorithms is investigated. Using the properties of spectral expansions, a novel parallel two domain procedure is generalized to an arbitrary number of domains each of which can be solved on a separate processor. This interface boundary condition considerably simplifies influence matrix techniques.

  17. Multimodal Revision Techniques in Webtexts

    ERIC Educational Resources Information Center

    Ball, Cheryl E.

    2014-01-01

    This article examines how an online scholarly journal, "Kairos: Rhetoric, Technology, Pedagogy," mentors authors to revise their webtexts (interactive, digital media scholarship) for publication. Using an editorial pedagogy in which multimodal and rhetorical genre theories are merged with revision techniques found in process-based…

  18. Optical interconnection techniques for Hypercube

    NASA Technical Reports Server (NTRS)

    Johnston, A. R.; Bergman, L. A.; Wu, W. H.

    1988-01-01

    Direct free-space optical interconnection techniques are described for the Hypercube concurrent processor machine using a holographic optical element. Computational requirements and optical constraints on implementation are briefly summarized with regard to topology, power consumption, and available technologies. A hybrid lens/HOE approach is described that can support an eight-dimensional cube of 256 nodes.

  19. Techniques for Use in Intervention.

    ERIC Educational Resources Information Center

    Thorne, Daniel R.

    1983-01-01

    Discusses an intervention technique that can be used in working with alcoholics and drug abusers who deny the need for help. The intervention focuses on the family, providing them with drug education and improved communication skills. Defusion, reframing, and positive data are used. The counselor's role is described. (JAC)

  20. Contrast-specific ultrasound techniques.

    PubMed

    Quaia, E

    2007-06-01

    The advent of microbubble contrast agents has determined an important evolution of ultrasound (US) technology due to the introduction of contrast-specific US techniques. This was due to the fact that neither colour or power Doppler are suitable for correct management of the signals produced by microbubble insonation, as they are limited by the heavy presence of artefacts. Microbubbles may be insonated by a characteristic frequency named resonance or fundamental frequency (f (0)) by using a high or low transmit power. If insonated by a high transmit power, microbubbles produce a wideband harmonic signal due to microbubble destruction. If insonated by a low transmit power, microbubbles produce harmonic frequencies (2f, 3f, 4f) due to their nonlinear physical behaviour. Contrast-specific US techniques have recently undergone an important technical development with the introduction of innovative algorithms able to register selectively the harmonic signals produced by microbubbles and to suppress the signal produced by stationary tissues. The different contrast-specific US techniques may be distinguished by their basic principle into pseudo-Doppler, harmonic, phase-modulation, amplitude-modulation and phase-and amplitude-modulation techniques.

  1. Theater As A Guidance Technique

    ERIC Educational Resources Information Center

    Wolpert, William

    1973-01-01

    Guidance-drama activity provides (a) crisp definitions of selected issues; (b) potent modeling from the characters in the play, the students actively engaged in the play, and the students involved in the discussions that follow the play; and (c) a technique for peer-led discussions on sensitive issues. This article gives precise definition to the…

  2. Advanced Geophysical Environmental Simulation Techniques

    DTIC Science & Technology

    2007-11-02

    cloud property retrieval algorithms for processing of large multiple-satellite data sets; development and application of improved cloud -phase and... cloud optical property retrieval algorithms; investigation of techniques potentially applicable for retrieval of cloud spatial properties from very...14. SUBJECT TERMS cirrus cloud retrieval satellite meteorology polar-orbiting geostationary 15. NUMBER OF PAGES 16. PRICE CODE 17. SECURITY

  3. Microprocessor Simulation: A Training Technique.

    ERIC Educational Resources Information Center

    Oscarson, David J.

    1982-01-01

    Describes the design and application of a microprocessor simulation using BASIC for formal training of technicians and managers and as a management tool. Illustrates the utility of the modular approach for the instruction and practice of decision-making techniques. (SK)

  4. Thematic Repetition as Rhetorical Technique.

    ERIC Educational Resources Information Center

    Allen, Jo

    1991-01-01

    Explores William Harvey's work, "On the Motion of the Heart and Blood in Animals." Highlights Harvey's fear of publication and his strategies for reducing resistance to his ideas. Underscores his use of circular references, metaphors, and organizational techniques that enhance and demonstrate his underlying thesis. (SG)

  5. Brain Friendly Techniques: Mind Mapping

    ERIC Educational Resources Information Center

    Goldberg, Cristine

    2004-01-01

    Mind Mapping can be called the Swiss Army Knife for the brain, a total visual thinking tool or a multi-handed thought catcher. Invented by Tony Buzan in the early 1970s and used by millions around the world, it is a method that can be a part of a techniques repertoire when teaching information literacy, planning, presenting, thinking, and so…

  6. Adhesiveless and grooveless sealing technique

    NASA Technical Reports Server (NTRS)

    Martin, J. W.; Elmendorf, H. M.

    1978-01-01

    Sealing technique eliminates groove or adhesive bonding and its attendant heating and curing need to finely finish at least one surface to be sealed. Seal could be mounted either inside or outside seal line, and could be installed in final assembly without exposing part to heat and pressure of curing.

  7. Techniques Class: September 12, 2001.

    ERIC Educational Resources Information Center

    More, William; Corsetti, Patricia L.; Endleman, Orna; Julian, Sarah; Lindemann, Evie; Spinelli, Laura

    2002-01-01

    On September 12, 2001, the Techniques in Art Therapy class in the art therapy program at Albertus Magnus College met at its normal Wednesday evening time. This article describes the class session through the words and images of several class members who found the class useful in their own process of beginning to deal with the attacks and their…

  8. [Evidence-based TEP technique].

    PubMed

    Köckerling, F

    2017-01-13

    The guidelines of all international hernia societies recommend as procedures of choice the laparoendoscopic techniques total extraperitoneal patch plasty (TEP) and transabdominal preperitoneal patch plasty (TAPP) as well as the open Lichtenstein operation for elective inguinal hernia repair. The learning curve associated with the laparoendoscopic techniques, in particular TEP, is longer than that for the open Lichtenstein technique due to the complexity of the procedures. Accordingly, for laparoendoscopic techniques it is particularly important that the operations are conducted in a standardized manner in compliance with the evidence-based recommendations given for the technical details. When procedures are carried out in strict compliance with the guidelines of the international hernia societies, low rates of perioperative complications, complication-related reoperations, recurrences and chronic pain can be expected for TEP. Compliance with the guidelines can also positively impact mastery of the learning curve for TEP. The technical guidelines on TEP are based on study results and on the experiences of numerous experts; therefore, it is imperative that they are implemented in routine surgical practice.

  9. TEACHING TECHNIQUES--SELECTED READINGS.

    ERIC Educational Resources Information Center

    Modern Language Association of America, New York, NY.

    A DIVERSIFIED SELECTION OF ARTICLES CONTAINING DESCRIPTIONS AND EXPLANATIONS OF TEACHING TECHNIQUES, PUBLISHED FROM 1961 TO 1967, IS PROVIDED IN THIS PACKET. INCLUDED ARE--(1) "TOWARD BETTER CLASSROOM TEACHING" (GREW), (2) "GOOD TEACHING PRACTICES--A SURVEY OF HIGH SCHOOL FL CLASSES" (HAMLIN AND OTHERS), (3) "LISTENING COMPREHENSION" (RIVERS), (4)…

  10. Counselling Techniques for Outdoor Leaders.

    ERIC Educational Resources Information Center

    Chase, Michelle; Chase, Robert

    1992-01-01

    Outdoor leaders need counseling skills to deal with interpersonal conflicts that arise within a group and to facilitate participant growth and change. Person-centered counseling, reality therapy counseling, and behavioral counseling are discussed, as well as how various techniques from each can be used to the benefit of the leader and the group.…

  11. Techniques of Assessing Mental Effort.

    ERIC Educational Resources Information Center

    Cennamo, Katherine S.

    The search for techniques to increase the effort that learners invest in video-based instruction has been hindered by the limitations of the instruments used to assess the construct of mental effort. Several researchers have noted the confusion of terms in the field that refer to the cognitive resources devoted to processing the stimulus. In this…

  12. Thematic Repetition as Rhetorical Technique.

    ERIC Educational Resources Information Center

    Allen, Jo

    1991-01-01

    Explores William Harvey's work, "On the Motion of the Heart and Blood in Animals." Highlights Harvey's fear of publication and his strategies for reducing resistance to his ideas. Underscores his use of circular references, metaphors, and organizational techniques that enhance and demonstrate his underlying thesis. (SG)

  13. Low background techniques in CANDLES

    SciTech Connect

    Nakajima, K. E-mail: nkyohei@u-fukui.ac.jp; Iida, T.; Matsuoka, K.; Nomachi, M.; Umehara, S.; Kishimoto, T.; Chan, W. M.; Kakubata, H.; Li, X.; Maeda, T.; Ohata, T.; Temuge, B.; Tetsuno, K.; Trang, V. T. T.; Uehara, T.; Yoshida, S.; Morishita, K.; Ogawa, I.; Sakamoto, K.; Tamagawa, Y.; and others

    2015-08-17

    CANDLES is a double beta decay experiment using {sup 48}Ca in CaF{sub 2} crystals. The measurement is being performed with prototype detector (CANDLES III) for high sensitive measurement in the future. Recent status of detector improvements and background reduction techniques are described in this paper.

  14. Advanced Intellect-Augmentation Techniques.

    ERIC Educational Resources Information Center

    Engelbart, D. C.

    This progress report covers a two-year project which is part of a program that is exploring the value of computer aids in augmenting human intellectual capability. The background and nature of the program, its resources, and the activities it has undertaken are outlined. User experience in applying augmentation tools and techniques to various…

  15. Bipulsating Technique for Silicon Production

    NASA Technical Reports Server (NTRS)

    Sanjurjo, A.

    1982-01-01

    Method controls reaction temperature and rate of reaction of sodium and silicon tetrafluoride by alternately adding measured amounts of reactants. Technique used in large reactor, where heat dissipation becomes serious problem, to control reactor temperatures. Highly efficient method, which would utilize almost 100 percent of raw materials.

  16. Identifying Major Techniques of Persuasion.

    ERIC Educational Resources Information Center

    Makosky, Vivian Parker

    1985-01-01

    The purpose of this class exercise is to increase undergraduate psychology students' awareness of common persuasion techniques used in advertising, including the appeal to or creation of needs, social and prestige suggestion, and the use of emotionally loaded words and images. Television commercials and magazine advertisements are used as…

  17. Radioactive-gas separation technique

    NASA Technical Reports Server (NTRS)

    Haney, R.; King, K. J.; Nellis, D. O.; Nisson, R. S.; Robling, P.; Womack, W.

    1977-01-01

    Cryogenic technique recovers gases inexpensively. Method uses differences in vapor pressures, melting points, and boiling points of components in gaseous mixture. Series of temperature and pressure variations converts gases independently to solid and liquid states, thereby simplifying separation. Apparatus uses readily available cryogen and does not require expensive refrigeration equipment.

  18. Low background techniques in CANDLES

    NASA Astrophysics Data System (ADS)

    Nakajima, K.; Iida, T.; Kishimoto, T.; Matsuoka, K.; Nomachi, M.; Umehara, S.; Chan, W. M.; Kakubata, H.; Li, X.; Maeda, T.; Ohata, T.; Temuge, B.; Tetsuno, K.; Trang, V. T. T.; Uehara, T.; Yoshida, S.; Morishita, K.; Ogawa, I.; Sakamoto, K.; Tamagawa, Y.; Yoshizawa, M.; Fushimi, K.; Hazama, R.; Naktani, N.; Suzuki, K.

    2015-08-01

    CANDLES is a double beta decay experiment using 48Ca in CaF2 crystals. The measurement is being performed with prototype detector (CANDLES III) for high sensitive measurement in the future. Recent status of detector improvements and background reduction techniques are described in this paper.

  19. Survey of Biochemical Separation Techniques

    ERIC Educational Resources Information Center

    Nilsson, Melanie R.

    2007-01-01

    A simple laboratory exercise is illustrated that exposes students to wide range of separation techniques in one laboratory program and provides a nice complement to a project-oriented program. Students have learned the basic principles of syringe filtration, centricon, dialysis, gel filtration and solid-phase extraction methodologies and have got…

  20. Cobbler's Technique for Iridodialysis Repair

    PubMed Central

    Pandav, Surinder Singh; Gupta, Parul Chawla; Singh, Rishi Raj; Das, Kalpita; Kaushik, Sushmita; Raj, Srishti; Ram, Jagat

    2016-01-01

    We describe a novel “Cobbler's technique” for iridodialysis repair in the right eye of a patient aged 18 years, with a traumatic iridodialysis secondary to open globe injury with an iron rod. Our technique is simple with easy surgical maneuvers, that is, effective for repairing iridodialysis. The “Cobbler's technique” allows a maximally functional and cosmetic result for iridodialysis. PMID:26957855

  1. Techniques in Advanced Language Teaching.

    ERIC Educational Resources Information Center

    Ager, D. E.

    1967-01-01

    For ease of presentation, advanced grammar teaching techniques are briefly considered under the headings of structuralism (belief in the effectiveness of presenting grammar rules) and contextualism (belief in the maximum use by students of what they know in the target language). The structuralist's problem of establishing a syllabus is discussed…

  2. Clustering Techniques in Speaker Recognition

    DTIC Science & Technology

    1994-03-01

    Quantization ................................ 9 2.5 Fuzzy Clustering ................................... 13 2.5.1 The Fuzzy k- Means Algorithm...techniques, vector quantization, Fuzzy k- Means and Artificial Neural Networks applied to speech for speaker identification. 2 II. Literature Review...recognition. Ruspini provided one of the first applications of fuzzy logic in clustering, he extended the conventional k- means algorithm into the Fuzzy k

  3. Time domain period determination techniques

    NASA Astrophysics Data System (ADS)

    Stellingwerf, R. F.

    1980-05-01

    Two simple period determination schemes are discussed. They are well suited to problems involving non-sinusoidal periodic phenomena sampled at a few irregularly spaced points. Statistical properties are discussed. The techniques are applied to the double mode Cepheids BK Cen and TU Cas as test cases.

  4. Quantitative Techniques in Volumetric Analysis

    NASA Astrophysics Data System (ADS)

    Zimmerman, John; Jacobsen, Jerrold J.

    1996-12-01

    Quantitative Techniques in Volumetric Analysis is a visual library of techniques used in making volumetric measurements. This 40-minute VHS videotape is designed as a resource for introducing students to proper volumetric methods and procedures. The entire tape, or relevant segments of the tape, can also be used to review procedures used in subsequent experiments that rely on the traditional art of quantitative analysis laboratory practice. The techniques included are: Quantitative transfer of a solid with a weighing spoon Quantitative transfer of a solid with a finger held weighing bottle Quantitative transfer of a solid with a paper strap held bottle Quantitative transfer of a solid with a spatula Examples of common quantitative weighing errors Quantitative transfer of a solid from dish to beaker to volumetric flask Quantitative transfer of a solid from dish to volumetric flask Volumetric transfer pipet A complete acid-base titration Hand technique variations The conventional view of contemporary quantitative chemical measurement tends to focus on instrumental systems, computers, and robotics. In this view, the analyst is relegated to placing standards and samples on a tray. A robotic arm delivers a sample to the analysis center, while a computer controls the analysis conditions and records the results. In spite of this, it is rare to find an analysis process that does not rely on some aspect of more traditional quantitative analysis techniques, such as careful dilution to the mark of a volumetric flask. Figure 2. Transfer of a solid with a spatula. Clearly, errors in a classical step will affect the quality of the final analysis. Because of this, it is still important for students to master the key elements of the traditional art of quantitative chemical analysis laboratory practice. Some aspects of chemical analysis, like careful rinsing to insure quantitative transfer, are often an automated part of an instrumental process that must be understood by the

  5. Cerebrovascular hemodynamics during pranayama techniques

    PubMed Central

    Nivethitha, L.; Mooventhan, A.; Manjunath, N. K.; Bathala, Lokesh; Sharma, Vijay K.

    2017-01-01

    Background: Pranayama techniques are known to produce variable physiological effects on the body. We evaluated the effect of the two commonly practiced Pranayama techniques on cerebral hemodynamics. Materials and Methods: Fifteen healthy male volunteers, trained in Yoga and Pranayama, were included in the study. Mean age was 24 years (range 22–32 years). Study participants performed 2 Pranayamas in 2 different orders. Order 1 (n = 7) performed Bhastrika (bellows breaths) followed by Kumbhaka (breath retention) while order 2 (n = 8) performed Kumbhaka followed by Bhastrika. Both breathing techniques were performed for 1 min each. Continuous transcranial Doppler (TCD) monitoring was performed during the breathing techniques. TCD parameters that were recorded included peak systolic velocity (PSV), end-diastolic velocity (EDV), mean flow velocity (MFV), and pulsatility index (PI) of the right middle cerebral artery at baseline, 15, 30, 45, and 60 s. Results: Significant reductions in EDV (3.67 ± 6.48; P < 0.001) and MFV (22.00 ± 7.30; P < 0.001) with a significant increase in PI (2.43 ± 0.76; P < 0.001) were observed during Bhastrika. On the contrary, a significant increase in PSV (65.27 ± 13.75; P < 0.001), EDV (28.67 ± 12.03; P < 0.001), and MFV (43.67 ± 12.85; P < 0.001) with a significant reduction in PI (0.89 ± 0.28; P < 0.01) was observed only during Kumbhaka. Conclusion: Bhastrika and Kumbhaka practices of Pranayama produce considerable and opposing effects on cerebral hemodynamic parameters. Our findings may play a potential role in designing the Pranayama techniques according to patients’ requirements. PMID:28149083

  6. The Use of Expressive Techniques in Counseling

    ERIC Educational Resources Information Center

    Bradley, Loretta J.; Whiting, Peggy; Hendricks, Bret; Parr, Gerald; Jones, Eugene Gordon, Jr.

    2008-01-01

    This manuscript explores and identifies the use of expressive techniques in counseling. Although verbal techniques are important, sometimes the best of verbal techniques are not sufficient. Creative, expressive techniques can add a new, important dimension to counseling. Such expressive techniques as cinema, art, and music are described to help…

  7. The Use of Expressive Techniques in Counseling

    ERIC Educational Resources Information Center

    Bradley, Loretta J.; Whiting, Peggy; Hendricks, Bret; Parr, Gerald; Jones, Eugene Gordon, Jr.

    2008-01-01

    This manuscript explores and identifies the use of expressive techniques in counseling. Although verbal techniques are important, sometimes the best of verbal techniques are not sufficient. Creative, expressive techniques can add a new, important dimension to counseling. Such expressive techniques as cinema, art, and music are described to help…

  8. Advanced Tools and Techniques for Formal Techniques in Aerospace Systems

    NASA Technical Reports Server (NTRS)

    Knight, John C.

    2005-01-01

    This is the final technical report for grant number NAG-1-02101. The title of this grant was "Advanced Tools and Techniques for Formal Techniques In Aerospace Systems". The principal investigator on this grant was Dr. John C. Knight of the Computer Science Department, University of Virginia, Charlottesville, Virginia 22904-4740. This report summarizes activities under the grant during the period 7/01/2002 to 9/30/2004. This report is organized as follows. In section 2, the technical background of the grant is summarized. Section 3 lists accomplishments and section 4 lists students funded under the grant. In section 5, we present a list of presentations given at various academic and research institutions about the research conducted. Finally, a list of publications generated under this grant is included in section 6.

  9. Ride quality research techniques: Section on scaling techniques

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Scaling techniques appropriate for the measurement of ride quality subjective responses are evaluated. The major focal points of interest are summarized in succeeding paragraphs as follow: (1) scope of scaling, (2) goal of scaling, (3) category scales; including polarity, scalar points, and whether the scale is discrete or continuous in nature, (4) need and use of adjectives and/or adverbs, (5) role and use of magnitude estimation, (6) multiple response measures; and (7) related topics.

  10. Consolidative Technique Otoplasty: Comprehensive Approach in Combining Techniques.

    PubMed

    Temel, Metin

    2016-12-01

    This study aimed to present the long-term results of the consolidative technique otoplasty (CTO). Patient age, sex, duration of follow-up, and how the deformity (bilateral-unilateral) occurred were determined. The kind of anesthesia, duration of surgery, surgical techniques used during the operation were reported, and the preoperative and postoperative distances between the ear and head were measured at four points (SUP: The highest point of the helix; SCA: the concha superior sticking points; ICA: stick point of Concha at the inferior; and lobular). Early- and late-term complications were recorded in the postoperative period. A total of 63 (21M-42FM) patients whose average age of 21:41 ± 8.96 (7-41), 119 ears (Right: 58/Left: 61) were operated on with this technique between 2013 and 2015. Mean follow-up was 18:22 ± 9:42 months. Anterior scoring was performed for three patients; concha resection was performed in 17 patients. Fifty-five patients were operated on as primary otoplasties and eight were secondary otoplasties. When the preoperative and postoperative SUP, SCA, ICA, and lobule measurements for both ears were compared, the postoperative values were found to be significantly decreased (p < 0.001). This technique may be an alternative in the repairs of prominent ears, and it provides an intervention opportunity for all the anatomical structures. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  11. Techniques for quantifying phytoplankton biodiversity.

    PubMed

    Johnson, Zackary I; Martiny, Adam C

    2015-01-01

    The biodiversity of phytoplankton is a core measurement of the state and activity of marine ecosystems. In the context of historical approaches, we review recent major advances in the technologies that have enabled deeper characterization of the biodiversity of phytoplankton. In particular, high-throughput sequencing of single loci/genes, genomes, and communities (metagenomics) has revealed exceptional phylogenetic and genomic diversity whose breadth is not fully constrained. Other molecular tools-such as fingerprinting, quantitative polymerase chain reaction, and fluorescence in situ hybridization-have provided additional insight into the dynamics of this diversity in the context of environmental variability. Techniques for characterizing the functional diversity of community structure through targeted or untargeted approaches based on RNA or protein have also greatly advanced. A wide range of techniques is now available for characterizing phytoplankton communities, and these tools will continue to advance through ongoing improvements in both technology and data interpretation.

  12. Historical Techniques of Lie Detection

    PubMed Central

    Vicianova, Martina

    2015-01-01

    Since time immemorial, lying has been a part of everyday life. For this reason, it has become a subject of interest in several disciplines, including psychology. The purpose of this article is to provide a general overview of the literature and thinking to date about the evolution of lie detection techniques. The first part explores ancient methods recorded circa 1000 B.C. (e.g., God’s judgment in Europe). The second part describes technical methods based on sciences such as phrenology, polygraph and graphology. This is followed by an outline of more modern-day approaches such as FACS (Facial Action Coding System), functional MRI, and Brain Fingerprinting. Finally, after the familiarization with the historical development of techniques for lie detection, we discuss the scope for new initiatives not only in the area of designing new methods, but also for the research into lie detection itself, such as its motives and regulatory issues related to deception. PMID:27247675

  13. LHC Olympics: Advanced Analysis Techniques

    NASA Astrophysics Data System (ADS)

    Armour, Kyle; Larkoski, Andrew; Gray, Amanda; Ventura, Dan; Walsh, Jon; Schabinger, Rob

    2006-05-01

    The LHC Olympics is a series of workshop aimed at encouraging theorists and experimentalists to prepare for the soon-to-be-online Large Hadron Collider in Geneva, Switzerland. One aspect of the LHC Olympics program consists of the study of simulated data sets which represent various possible new physics signals as they would be seen in LHC detectors. Through this exercise, LHC Olympians learn the phenomenology of possible new physics models and gain experience in analyzing LHC data. Additionally, the LHC Olympics encourages discussion between theorists and experimentalists, and through this collaboration new techniques could be developed. The University of Washington LHC Olympics group consists of several first-year graduate and senior undergraduate students, in both theoretical and experimental particle physics. Presented here is a discussion of some of the more advanced techniques used and the recent results of one such LHC Olympics study.

  14. Techniques for Quantifying Phytoplankton Biodiversity

    NASA Astrophysics Data System (ADS)

    Johnson, Zackary I.; Martiny, Adam C.

    2015-01-01

    The biodiversity of phytoplankton is a core measurement of the state and activity of marine ecosystems. In the context of historical approaches, we review recent major advances in the technologies that have enabled deeper characterization of the biodiversity of phytoplankton. In particular, high-throughput sequencing of single loci/genes, genomes, and communities (metagenomics) has revealed exceptional phylogenetic and genomic diversity whose breadth is not fully constrained. Other molecular tools—such as fingerprinting, quantitative polymerase chain reaction, and fluorescence in situ hybridization—have provided additional insight into the dynamics of this diversity in the context of environmental variability. Techniques for characterizing the functional diversity of community structure through targeted or untargeted approaches based on RNA or protein have also greatly advanced. A wide range of techniques is now available for characterizing phytoplankton communities, and these tools will continue to advance through ongoing improvements in both technology and data interpretation.

  15. Ultrasonic thermometry using pulse techniques.

    NASA Technical Reports Server (NTRS)

    Lynnworth, L. C.; Carnevale, E. H.

    1972-01-01

    Ultrasonic pulse techniques have been developed which, when applied to inert gases, provide temperature measurements up to 8000 K. The response time can be less than 1 msec. This is a significant feature in studying shock-heated or combusting gases. Using a momentary contact coupling technique, temperature has been measured inside steel from 300 to 1500 K. Thin-wire sensors have been used above 2000 K in nuclear and industrial applications where conditions preclude the use of thermocouples, resistance devices, or optical pyrometers. At 2500 K, temperature sensitivity of 0.1% is obtained in Re wire sensors 5 cm long by timing five round trips with an electronic instrument that resolves the time interval between selected echoes to 0.1 microsec. Sensors have been operated at rotational speeds over 2000 rpm and in noisy environments. Temperature profiling of up to ten regions using only a single guided path or beam has also been accomplished.

  16. Synchrotron radiation techniques for nanotoxicology.

    PubMed

    Li, Yu-Feng; Zhao, Jiating; Qu, Ying; Gao, Yuxi; Guo, Zhenghang; Liu, Zuoliang; Zhao, Yuliang; Chen, Chunying

    2015-08-01

    Nanotoxicology studies the interactions of engineered nanomaterials with biological systems. Traditional in vitro and in vivo toxicological assays have been successfully employed. However, the toxicological mechanisms of nanoparticles might not be the same as those incurred in traditional molecular toxicology. Furthermore, how to realize in situ and real time measurements especially in the biological microenvironment is still a challenge. Synchrotron radiation, which is highly polarized and tunable, has been proved to play an indispensible role for nanotoxicology studies. In this review, the role of synchrotron radiation techniques is summarized in screening physicochemical characteristics, in vitro and in vivo behaviors, and ecotoxicological effects of engineered nanomaterials. The rapid gain in popularity of nanomaterials has also raised the concern of nanotoxicity, which needs to be assessed and addressed. In this comprehensive review, the authors outlined the underlying principles of using synchrotron radiation techniques for nanotoxicology studies and also in other scientific fields. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Genetics Techniques for Thermococcus kodakarensis

    PubMed Central

    Hileman, Travis H.; Santangelo, Thomas J.

    2012-01-01

    Thermococcus kodakarensis (T. kodakarensis) has emerged as a premier model system for studies of archaeal biochemistry, genetics, and hyperthermophily. This prominence is derived largely from the natural competence of T. kodakarensis and the comprehensive, rapid, and facile techniques available for manipulation of the T. kodakarensis genome. These genetic capacities are complemented by robust planktonic growth, simple selections, and screens, defined in vitro transcription and translation systems, replicative expression plasmids, in vivo reporter constructs, and an ever-expanding knowledge of the regulatory mechanisms underlying T. kodakarensis metabolism. Here we review the existing techniques for genetic and biochemical manipulation of T. kodakarensis. We also introduce a universal platform to generate the first comprehensive deletion and epitope/affinity tagged archaeal strain libraries. PMID:22701112

  18. Clear air turbulence forecasting techniques

    NASA Technical Reports Server (NTRS)

    Keller, J. L.

    1980-01-01

    A method to improve clear air turbulence (CAT) forecasting by more effectively using the currently operational rawinsonde (RW) system is discussed. The method is called the Diagnostic Richardson Number Tendency (DRT) technique. The technique does not attempt to use the RW as a direct detector of the turbulent motion or even of the CAT mechanism structure but rather senses the synoptic scale centers of action which provide the energy to the CAT mechanism at the mesoscale level. The DRT algorithm is deterministic rather than statistical in nature, using the hydrodynamic equations (equations of motion) relevant to the synoptic scale. However, interpretation, by necessity, is probabilistic. What is most important with respect to its operational implementation is that this method uses the same input data as currently used by the operational National Meteorological Center prognostic models.

  19. Technique and staining optimization leucoconcentration.

    PubMed

    Pierrez, J; Guerci, A; Guerci, O

    1987-09-01

    In cytometric clinical application, it is important to obtain cell suspensions rapidly with as little cytological alteration as possible. A procedure has been achieved to prepare cell suspensions for flow cytometric analysis. The leucoconcentration technique, first described by Herbeuval for cytologic analysis, has been modified to be applied in cytometry. This technique involves Saponin lysis of red cells of peripheral blood or bone marrow samples that have been previously fixed with picric acid alcohol solution. Cells in suspension are not shifted and tinctorial affinity is not modified. Then cells have been stained with Mithramycin. Each parameter defined by Crissman has been analyzed to define the best staining conditions. The availability of Leucoconcentration with Mithramycin-DNA-staining permits determination of cell cycle with a fine resolution.

  20. Hand lay-up techniques

    NASA Astrophysics Data System (ADS)

    Wittman, C.; Shook, G. D.

    The materials, processes, and techniques, as well as comparisons of various hand and spray-up FRP finished product manufacturing procedures are presented. The steps followed in producing a finished product are noted to nominally comprise coating a form with a gel, build-up of the structure with reinforcing fibers and catalyzed polyester resin, curing, and impaction to remove trapped air. The part emerges with a finished surface prepainted by the gel. Design choices for the percentages and orientation of the reinforcement, the types of fillers, and the types of resins are dictated by the types and intensity of stresses to be encountered by the part in actual use. Examples are provided of the manufacture of a machine cover, a pressure tank formerly made of metal. Techniques for assuring integrity of the laminate in changes of thickness, joints, openings, and severe contours are described.

  1. [Useful radiological techniques in orthodontics].

    PubMed

    Felizardo, Rufino; Thomas, Alexis; Foucart, Jean-Michel

    2012-03-01

    Specialists in dento-facial orthopedics have a large range of dental radiological techniques at their disposal to help them in their diagnostic and therapeutic procedures. Peri-apical, occlusal, panoramic, and cephalometric X-Rays are two-dimensional techniques that orthodontists can complement, if necessary, with Multi slices CT scan or Cone Beam Computed Tomography. Orthodontists must apply and respect quality criteria for each type of film in order to derive the best information from every image and to avoid producing artifacts or false images that will reduce their diagnostic value and, accordingly, the service that they render to patients. Practitioners must be willing to spend the few moments it takes to position patients correctly in the radiological apparatus instead of taking multiple views to compensate for failing to scrupulously follow protocols of radiology.

  2. Techniques for integrating -omics data.

    PubMed

    Akula, Siva Prasad; Miriyala, Raghava Naidu; Thota, Hanuman; Rao, Allam Appa; Gedela, Srinubabu

    2009-01-01

    The challenge for -omics research is to tackle the problem of fragmentation of knowledge by integrating several sources of heterogeneous information into a coherent entity. It is widely recognized that successful data integration is one of the keys to improve productivity for stored data. Through proper data integration tools and algorithms, researchers may correlate relationships that enable them to make better and faster decisions. The need for data integration is essential for present -omics community, because -omics data is currently spread world wide in wide variety of formats. These formats can be integrated and migrated across platforms through different techniques and one of the important techniques often used is XML. XML is used to provide a document markup language that is easier to learn, retrieve, store and transmit. It is semantically richer than HTML. Here, we describe bio warehousing, database federation, controlled vocabularies and highlighting the XML application to store, migrate and validate -omics data.

  3. Clear air turbulence forecasting techniques

    NASA Technical Reports Server (NTRS)

    Keller, J. L.

    1980-01-01

    A method to improve clear air turbulence (CAT) forecasting by more effectively using the currently operational rawinsonde (RW) system is discussed. The method is called the Diagnostic Richardson Number Tendency (DRT) technique. The technique does not attempt to use the RW as a direct detector of the turbulent motion or even of the CAT mechanism structure but rather senses the synoptic scale centers of action which provide the energy to the CAT mechanism at the mesoscale level. The DRT algorithm is deterministic rather than statistical in nature, using the hydrodynamic equations (equations of motion) relevant to the synoptic scale. However, interpretation, by necessity, is probabilistic. What is most important with respect to its operational implementation is that this method uses the same input data as currently used by the operational National Meteorological Center prognostic models.

  4. A new atrial septostomy technique.

    PubMed

    Park, S C; Zuberbuhler, J R; Neches, W H; Lenox, C C; Zoltun, R A

    1975-01-01

    Balloon atrial septostomy is usually ineffective if the atrial septum is thickened. A technique for incising the atrial septum is described. A no. 6 French catheter was modified to enclose a tiny surgical blade. The distal end of the blade was pivoted to the catheter tip, and the proximal end was attached to a guide wire in the catheter lumen. Advancing the guide wire protruded the blade through a slit in the long axis of the tip of the catheter. Atrial septostomy was performed in five newborn lambs in vivo and in adult dog hearts and human hearts in vitro by advancing the catheter tip across the atrial septum with the blade retracted and withdrawing it to the right atrium with the blade extended. Eight to 12 mm lacerations of the atrial septum were produced and could be extended by subsequent balloon septostomy. The technique may be useful when balloon septostomy has been ineffective.

  5. The Proxy+Matching Technique

    NASA Astrophysics Data System (ADS)

    Muñoz Arancibia, A. M.; Padilla, N. D.; Cora, S. A.; Gawiser, E.; Navarrete, F. P.; Orsi, A. A.; Guaita, L.; Kurczynski, P.; Ruiz, A. N.

    2017-07-01

    We introduce a novel technique for modeling luminosities at different wavelengths in large samples of galaxies, suitable for emission processes whose complexity requires many untested assumptions or the use of sophisticated algorithms: in the "Proxy+Matching" approach, a physical galaxy property from the model is chosen as a proxy for another property whose numerical value is unknown. Both proxy and unknown are assumed to follow a monotonic relationship, assigning that unknown to the simulated galaxies in such a way that some observational statistics for it are reproduced. By comparing the predictions for further galaxy properties with observations, a good proxy can be found. We present the prospects of this technique for probing the submillimeter and Lyman alpha emission from galaxies in a cosmological framework, using a semi-analytic model of galaxy formation and evolution.

  6. Historical Techniques of Lie Detection.

    PubMed

    Vicianova, Martina

    2015-08-01

    Since time immemorial, lying has been a part of everyday life. For this reason, it has become a subject of interest in several disciplines, including psychology. The purpose of this article is to provide a general overview of the literature and thinking to date about the evolution of lie detection techniques. The first part explores ancient methods recorded circa 1000 B.C. (e.g., God's judgment in Europe). The second part describes technical methods based on sciences such as phrenology, polygraph and graphology. This is followed by an outline of more modern-day approaches such as FACS (Facial Action Coding System), functional MRI, and Brain Fingerprinting. Finally, after the familiarization with the historical development of techniques for lie detection, we discuss the scope for new initiatives not only in the area of designing new methods, but also for the research into lie detection itself, such as its motives and regulatory issues related to deception.

  7. A tire contact solution technique

    NASA Technical Reports Server (NTRS)

    Tielking, J. T.

    1983-01-01

    An efficient method for calculating the contact boundary and interfacial pressure distribution was developed. This solution technique utilizes the discrete Fourier transform to establish an influence coefficient matrix for the portion of the pressurized tire surface that may be in the contact region. This matrix is used in a linear algebra algorithm to determine the contact boundary and the array of forces within the boundary that are necessary to hold the tire in equilibrium against a specified contact surface. The algorithm also determines the normal and tangential displacements of those points on the tire surface that are included in the influence coefficient matrix. Displacements within and outside the contact region are calculated. The solution technique is implemented with a finite-element tire model that is based on orthotropic, nonlinear shell of revolution elements which can respond to nonaxisymmetric loads. A sample contact solution is presented.

  8. Apoptosis Evaluation by Electrochemical Techniques.

    PubMed

    Yin, Jian; Miao, Peng

    2016-03-04

    Apoptosis has close relevance to pathology, pharmacology, and toxicology. Accurate and convenient detection of apoptosis would be beneficial for biological study, clinical diagnosis, and drug development. Based on distinct features of apoptotic cells, a diversity of analytical techniques have been exploited for sensitive analysis of apoptosis, such as surface plasmon resonance, electrochemical methods, flow cytometry, and some imaging assays. Among them, the features of simplicity, easy operation, low cost, and high sensitivity make electrochemical techniques powerful tools to investigate electron-transfer processes of in vitro biological systems. In this contribution, a general overview of current knowledge on various technical approaches for apoptosis evaluation is provided. Furthermore, recently developed electrochemical biosensors for detecting apoptotic cells and their advantages over traditional methods are summarized. One of the main considerations focuses on designing the recognition elements based on various biochemical events during apoptosis.

  9. Flip-chip and backside techniques.

    SciTech Connect

    Bernhard-Hofer, Karoline; Barton, Daniel Lee; Cole, Edward Isaac, Jr.

    2010-08-01

    State-of-the-art techniques for failure localization and design modification through bulk silicon are essential for multi-level metallization and new, flip chip packaging methods. The tutorial reviews the transmission of light through silicon, sample preparation, and backside defect localization techniques that are both currently available and under development. The techniques covered include emission microscopy, scanning laser microscope based techniques (electrooptic techniques, LIVA and its derivatives), and other non-IR based tools (FIB, e-beam techniques, etc.).

  10. Research in millimeter wave techniques

    NASA Technical Reports Server (NTRS)

    Forsythe, R. E.

    1982-01-01

    Subharmonically pumped mixers were ascended and tested. A computerized version of the automatic noise figure measurement system was developed. Impedance matching techniques suitable for these types of mixers were investigated. Narrow and broadband (one octave) matching networks for the subharmonic mixers were designed. The automatic mixer noise figure test facility was completed. Subharmonic mixers and the systems that use them at 183 and 220 GHz were evaluated and characterized.

  11. Radon assay and purification techniques

    SciTech Connect

    Simgen, Hardy

    2013-08-08

    Radon is a source of background in many astroparticle physics experiments searching for rare low energy events. In this paper an overview about radon in the field is given including radon detection techniques, radon sources and material screening with respect to radon emanation. Finally, also the problem of long-lived radioactive {sup 222}Rn-daughters and the question of gas purification from radon is addressed.

  12. Acoustic techniques in nuclear safeguards

    SciTech Connect

    Olinger, C.T.; Sinha, D.N.

    1995-07-01

    Acoustic techniques can be employed to address many questions relevant to current nuclear technology needs. These include establishing and monitoring intrinsic tags and seals, locating holdup in areas where conventional radiation-based measurements have limited capability, process monitoring, monitoring containers for corrosion or changes in pressure, and facility design verification. These acoustics applications are in their infancy with respect to safeguards and nuclear material management, but proof-of-principle has been demonstrated in many of the areas listed.

  13. A MEASUREMENT TECHNIQUE FOR HYDROXYACETONE.

    SciTech Connect

    KLOTZ,P.J.

    1999-10-04

    Hydroxyacetone (HA) is mainly produced in the atmosphere from oxidation of hydrocarbons of the type, CH{sub 3}(R)C=CH{sub 2}. Tuazon and Atkinson (1990) reported HA yield of 41% from the OH-initiated oxidation of methacrolein in the presence of NO{sub x}. Since methacrolein is a major product of isoprene oxidation (Carter and Atkinson, 1996), isoprene, a key biogenic hydrocarbon, is therefore expected to be an important source for HA. Consequently, knowledge of ambient concentration of HA would provide information needed to examine the applicability of isoprene reaction mechanisms developed in laboratory and to assess the contribution of isoprene to photooxidant production. The commonly used GC-FID technique involving cryo-focusing is unsuitable for HA owing to HA's thermal instability. When subjected to a temperature of 100 C for only a few seconds, HA was found to disappear completely. Since HA is highly soluble in water (it's Henry's law constant being {approx}2 x 10{sup 4} M atm{sup -1} at 20 C, Zhou and Lee, unpublished data), we developed a wet chemical technique similar in principle to the one we reported earlier (Lee and Zhou, 1993), namely, based on derivatization following liquid scrubbing. To increase the sensitivity, we adopted a fluorescence detection scheme based on o-phthaldialdehyde (OPA) chemistry. The technique was deployed in the field during two measurement periods at a NARSTO site located on Long Island (LI), New York. We report the principle and the operation of this technique and the results obtained from these field studies.

  14. Data mining and visualization techniques

    DOEpatents

    Wong, Pak Chung; Whitney, Paul; Thomas, Jim

    2004-03-23

    Disclosed are association rule identification and visualization methods, systems, and apparatus. An association rule in data mining is an implication of the form X.fwdarw.Y where X is a set of antecedent items and Y is the consequent item. A unique visualization technique that provides multiple antecedent, consequent, confidence, and support information is disclosed to facilitate better presentation of large quantities of complex association rules.

  15. Survey of Header Compression Techniques

    NASA Technical Reports Server (NTRS)

    Ishac, Joseph

    2001-01-01

    This report provides a summary of several different header compression techniques. The different techniques included are: (1) Van Jacobson's header compression (RFC 1144); (2) SCPS (Space Communications Protocol Standards) header compression (SCPS-TP, SCPS-NP); (3) Robust header compression (ROHC); and (4) The header compression techniques in RFC2507 and RFC2508. The methodology for compression and error correction for these schemes are described in the remainder of this document. All of the header compression schemes support compression over simplex links, provided that the end receiver has some means of sending data back to the sender. However, if that return path does not exist, then neither Van Jacobson's nor SCPS can be used, since both rely on TCP (Transmission Control Protocol). In addition, under link conditions of low delay and low error, all of the schemes perform as expected. However, based on the methodology of the schemes, each scheme is likely to behave differently as conditions degrade. Van Jacobson's header compression relies heavily on the TCP retransmission timer and would suffer an increase in loss propagation should the link possess a high delay and/or bit error rate (BER). The SCPS header compression scheme protects against high delay environments by avoiding delta encoding between packets. Thus, loss propagation is avoided. However, SCPS is still affected by an increased BER (bit-error-rate) since the lack of delta encoding results in larger header sizes. Next, the schemes found in RFC2507 and RFC2508 perform well for non-TCP connections in poor conditions. RFC2507 performance with TCP connections is improved by various techniques over Van Jacobson's, but still suffers a performance hit with poor link properties. Also, RFC2507 offers the ability to send TCP data without delta encoding, similar to what SCPS offers. ROHC is similar to the previous two schemes, but adds additional CRCs (cyclic redundancy check) into headers and improves

  16. Selenium incorporation using recombinant techniques.

    PubMed

    Walden, Helen

    2010-04-01

    Using selenomethionine to phase macromolecular structures is common practice in structure determination, along with the use of selenocysteine. Selenium is consequently the most commonly used heavy atom for MAD. In addition to the well established recombinant techniques for the incorporation of selenium in prokaryal expression systems, there have been recent advances in selenium labelling in eukaryal expression, which will be discussed. Tips and things to consider for the purification and crystallization of seleno-labelled proteins are also included.

  17. Advanced intellect-augmentation techniques

    NASA Technical Reports Server (NTRS)

    Engelbart, D. C.

    1972-01-01

    User experience in applying our augmentation tools and techniques to various normal working tasks within our center is described so as to convey a subjective impression of what it is like to work in an augmented environment. It is concluded that working-support, computer-aid systems for augmenting individuals and teams, are undoubtedly going to be widely developed and used. A very special role in this development is seen for multi-access computer networks.

  18. Characterization Techniques for Amorphous Alloys

    NASA Astrophysics Data System (ADS)

    Carow-Watamura, U.; Louzguine, D. V.; Takeuchi, A.

    This document is part of Part 2 http://dx.doi.org/10.1007/9getType="URL"/> 'Systems from B-Be-Fe to Co-W-Zr' of Subvolume B 'Physical Properties of Ternary Amorphous Alloys' of Volume 37 'Phase Diagrams and Physical Properties of Nonequilibrium Alloys' of Landolt-Börnstein - Group III 'Condensed Matter'. It contains the Chapter '2 Characterization Techniques for Amorphous Alloys' with the content:

  19. AC electrothermal technique in microchannels

    NASA Astrophysics Data System (ADS)

    Salari, Alinaghi; Navi, Maryam; Dalton, Colin

    2017-02-01

    Electrokinetic techniques have a wide range of applications in droplet, particle, and fluid manipulation systems. In general, they can be categorized into different subgroups including electroosmosis, electrothermal, electrophoresis, dielectrophoresis, etc. The AC electrothermal (ACET) technique has been shown to be very effective in applications which involve high conductivity fluids, such as blood, which are typically used in biomedical applications. In the past few years, the ACET effect has received considerable attention. Unlike AC electroosmosis (ACEO), the ACET effect shows plateaus in force in a wide frequency range. In other words, with electrothermal force, velocity is more steady and predictable at different frequencies, compared to ACEO and dielectrophoresis (DEP). Although electrothermal microflows form as a result of Joule heating in the fluid, due to high conduction of heat to the ambience, the temperature rise in the fluid is not so high as to threaten the nature of the biofluids. The average temperature rise resulting from the ACET effect is below 5 °K. In order to generate high strength AC electric fields, microfabricated electrode arrays are commonly used in microchannels. For pumping applications, it is essential to create asymmetry in the electric field, typically by having asymmetrical electrode pairs. There is no defined border between many electrokinetic techniques, and as such the point where electrothermal processes interferes with other electrokinetic techniques is not clear in the literature. In addition, there have been comprehensive reviews on micropumps, electrokinetics, and their subcategories, but the literature lacks a detailed up-to-date review on electrothermal microdevices. In this paper, a brief review is made specifically on electric fields in ACET devices, in order to provide an insight for the reader about the importance of this aspect of ACET devices and the improvements made to date.

  20. Instrumental Techniques in Archeological Research

    DTIC Science & Technology

    1988-09-01

    instantaneously, and as a result archeomagnetic studies have become more numerous and effective. P. C. Hammond, " Archaeometry and Time: A Review," Journal of...Trapped Electron Dating," Journal of Geophysical Research , Vol 76 (1971), pp 7875-7887. 25 keya, M. and Miki, T., "Electron Spin Resonance Dating of...1974, " Archaeometry and Time: A Review," Journal of Field Archae- ology 1, pp 329-335. Excellent brief summary of history of technique and its

  1. Lightning Simulation Test Technique Evaluation

    DTIC Science & Technology

    1988-10-01

    Example Resistive Response Measurement 94 43 Example dI/dt Response Measurement 95 44 Statistical Distribution of Swept CW Extrapolated Values - Nose...Aircraft 2 2 Prior Research and Development Tests on Full-Scale Air Vehicles 10 3 Summary of Simulation Technique Capabilities 14 4 Test Bed Resistance ...second L Inductance henrys R Resistance ohms V Potential difference volts STANDARD UNITS A amperes dB, dBm decibels Hz hertz kA kiloamps kV kilovolts

  2. Enteral Feeding Set Handling Techniques.

    PubMed

    Lyman, Beth; Williams, Maria; Sollazzo, Janet; Hayden, Ashley; Hensley, Pam; Dai, Hongying; Roberts, Cristine

    2017-04-01

    Enteral nutrition therapy is common practice in pediatric clinical settings. Often patients will receive a pump-assisted bolus feeding over 30 minutes several times per day using the same enteral feeding set (EFS). This study aims to determine the safest and most efficacious way to handle the EFS between feedings. Three EFS handling techniques were compared through simulation for bacterial growth, nursing time, and supply costs: (1) rinsing the EFS with sterile water after each feeding, (2) refrigerating the EFS between feedings, and (3) using a ready-to-hang (RTH) product maintained at room temperature. Cultures were obtained at baseline, hour 12, and hour 21 of the 24-hour cycle. A time-in-motion analysis was conducted and reported in average number of seconds to complete each procedure. Supply costs were inventoried for 1 month comparing the actual usage to our estimated usage. Of 1080 cultures obtained, the overall bacterial growth rate was 8.7%. The rinse and refrigeration techniques displayed similar bacterial growth (11.4% vs 10.3%, P = .63). The RTH technique displayed the least bacterial growth of any method (4.4%, P = .002). The time analysis in minutes showed the rinse method was the most time-consuming (44.8 ± 2.7) vs refrigeration (35.8 ± 2.6) and RTH (31.08 ± 0.6) ( P < .0001). All 3 EFS handling techniques displayed low bacterial growth. RTH was superior in bacterial growth, nursing time, and supply costs. Since not all pediatric formulas are available in RTH, we conclude that refrigerating the EFS between uses is the next most efficacious method for handling the EFS between bolus feeds.

  3. Monolithic microcircuit techniques and processes

    NASA Technical Reports Server (NTRS)

    Kennedy, B. W.

    1972-01-01

    Brief discussions of the techniques used to make dielectric and metal thin film depositions for monolithic circuits are presented. Silicon nitride deposition and the properties of silicon nitride films are discussed. Deposition of dichlorosilane and thermally grown silicon dioxide are reported. The deposition and thermal densification of borosilicate, aluminosilicate, and phosphosilicate glasses are discussed. Metallization for monolithic circuits and the characteristics of thin films are also included.

  4. Chest physiotherapy techniques in bronchiectasis.

    PubMed

    Flude, Lizzie J; Agent, Penny; Bilton, Diana

    2012-06-01

    Bronchiectasis is a persistent and progressive condition characterized by inflammation and infection causing damage that potentiates impaired mucociliary clearance. The rationale for promoting airway clearance is so that purulent secretions are removed from the airways, ameliorating the inflammation and improving control of symptoms such as cough and sputum plugging. Physiotherapists aim to teach patients one of a variety of airway clearance techniques to regularly perform as part of their daily management. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Climbing techniques for bridge inspection

    NASA Astrophysics Data System (ADS)

    Kaslan, Erol C.

    1998-03-01

    California has about 24,000 publicly owned bridges that require routine structural evaluations to comply with National Bridge Inspection Standard (NBIS) mandates. Of these, about 800 are identified as possessing fatigue prone or fracture critical details requiring thorough tactile investigations. Gaining access to bridge elements to perform these investigations has become increasingly difficult and costly. The traditional uses of under bridge inspection trucks, lift equipment and rigging are economically and practically limited by bridge size, structure type, traffic demands and support costs. In some cases, bridges that have become damaged by earthquakes cannot safely support the loads of heavy personnel lift equipment. The California Department of Transportation (Caltrans)'s Office of Structural Materials and Office of Structure Maintenance and Investigations evaluated the use of rock climbing and mountaineering techniques as an alternative means of gaining access for bridge inspections. Under a small research grant, a bridge climbing training course was developed through a local University of California outdoor recreation group and 7 engineers and technicians were initially trained. A comprehensive Code of Safe Practices was created and standards of training, procedures and equipment required for bridge inspections were established. A successful climb investigation on a large, previously inaccessible arch bridge was completed at the end of the training that proved the techniques safe, economical and effective. Within one year, 20 bridge maintenance engineers were trained, and a formal program was established to organize, schedule, equip and certify engineers and technicians for bridge climbing. Several other offices within Caltrans as well as the California Department of Water Resources have since adopted these techniques for specialized structural inspection tasks. Climbing techniques are now used routinely in California as an alterative means of gaining access

  6. Guide to molecular cloning techniques

    SciTech Connect

    Berger, S.L.; Kimmel, A.R.

    1987-01-01

    This book includes the following selections: requirements for a molecular biology laboratory; general methods for isolating and characterizing nucleic acids; enzymatic techniques and recombinant DNA technology; restriction enzymes; growth and maintenance of bacteria; genetic cloning, preparation and characterization of RNA; preparation of cDNA and the generation of cDNA libraries; selections of clones from libraries; and identification and characterization of specific clones.

  7. Surface Characterization Techniques: An Overview

    NASA Technical Reports Server (NTRS)

    Miyoshi, Kazuhisa

    2002-01-01

    To understand the benefits that surface modifications provide, and ultimately to devise better ones, it is necessary to study the physical, mechanical, and chemical changes they cause. This chapter surveys classical and leading-edge developments in surface structure and property characterization methodologies. The primary emphases are on the use of these techniques as they relate to surface modifications, thin films and coatings, and tribological engineering surfaces and on the implications rather than the instrumentation.

  8. Computational intelligence techniques in bioinformatics.

    PubMed

    Hassanien, Aboul Ella; Al-Shammari, Eiman Tamah; Ghali, Neveen I

    2013-12-01

    Computational intelligence (CI) is a well-established paradigm with current systems having many of the characteristics of biological computers and capable of performing a variety of tasks that are difficult to do using conventional techniques. It is a methodology involving adaptive mechanisms and/or an ability to learn that facilitate intelligent behavior in complex and changing environments, such that the system is perceived to possess one or more attributes of reason, such as generalization, discovery, association and abstraction. The objective of this article is to present to the CI and bioinformatics research communities some of the state-of-the-art in CI applications to bioinformatics and motivate research in new trend-setting directions. In this article, we present an overview of the CI techniques in bioinformatics. We will show how CI techniques including neural networks, restricted Boltzmann machine, deep belief network, fuzzy logic, rough sets, evolutionary algorithms (EA), genetic algorithms (GA), swarm intelligence, artificial immune systems and support vector machines, could be successfully employed to tackle various problems such as gene expression clustering and classification, protein sequence classification, gene selection, DNA fragment assembly, multiple sequence alignment, and protein function prediction and its structure. We discuss some representative methods to provide inspiring examples to illustrate how CI can be utilized to address these problems and how bioinformatics data can be characterized by CI. Challenges to be addressed and future directions of research are also presented and an extensive bibliography is included. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Control technique for planetary rover

    NASA Technical Reports Server (NTRS)

    Nakatani, Ichiro; Kubota, Takashi; Adachi, Tadashi; Saitou, Hiroaki; Okamoto, Sinya

    1994-01-01

    Beginning next century, several schemes for sending a planetary rover to the moon or Mars are being planned. As part of the development program, autonomous navigation technology is being studied to allow the rover the ability to move autonomously over a long range of unknown planetary surface. In the previous study, we ran the autonomous navigation experiment on an outdoor test terrain by using a rover test-bed that was controlled by a conventional sense-plan-act method. In some cases during the experiment, a problem occurred with the rover moving into untraversable areas. To improve this situation, a new control technique has been developed that gives the rover the ability of reacting to the outputs of the proximity sensors, a reaction behavior if you will. We have developed a new rover test-bed system on which an autonomous navigation experiment was performed using the newly developed control technique. In this outdoor experiment, the new control technique effectively produced the control command for the rover to avoid obstacles and be guided to the goal point safely.

  10. Techniques to accelerate dynamic psychotherapy.

    PubMed

    Fosha, D; Slowiaczek, M L

    1997-01-01

    The techniques described above outline specific ways to deepen the patient's affective experience within an emotionally close therapeutic relationship. When effective, they all enhance the patient/therapist bond, raise self-esteem, reduce defensiveness and anxiety, and facilitate emotional healing. Psychodynamic treatment, long or short, is a complex process uniquely constructed by each therapist/patient pair. AEDP strategies are not intended as recipes for treatment. Good dynamic work depends on the therapist's ability to grasp the patient's capacities and limitations, understand relational dynamics, and interact with the patient in an empathically attuned, emotionally receptive, and flexible way. In that context, these strategies can be helpful tools to facilitate and accelerate the process. The choices made by AEDP--privileging adaptive strivings over defensive reactions, the stance of emotional engagement rather than neutrality and abstinence, the focus on health and change over pathology and stasis--are informed by traditional STDP aims to maximize depth, effectiveness, and efficiency. AEDP's contribution is a set of techniques relying on a response repertoire that is available to a wide range of therapists. Therapists can use these techniques to be more effective while simultaneously retaining the experience of speaking with patients in an authentic voice.

  11. Techniques for Specifying Bug Patterns

    SciTech Connect

    Quinlan, D J; Vuduc, R W; Misherghi, G

    2007-04-30

    We present our on-going work to develop techniques for specifying source code signatures of bug patterns. Specifically, we discuss two approaches. The first approach directly analyzes a program in the intermediate representation (IR) of the ROSE compiler infrastructure using ROSE's API. The second analyzes the program using the bddbddb system of Lam, Whaley, et al.. In this approach, we store the IR produced by ROSE as a relational database, express patterns as declarative inference rules on relations in the language Datalog, and bddbddb implements the Datalog programs using binary decision diagram (BDD) techniques. Both approaches readily apply to large-scale applications, since ROSE provides full type analysis, control flow, and other available analysis information. In this paper, we primarily consider bug patterns expressed with respect to the structure of the source code or the control flow, or both. More complex techniques to specify patterns that are functions of data flow properties may be addressed by either of the above approaches, but are not directly treated here. Our Datalog-based work includes explicit support for expressing patterns on the use of the Message Passing Interface (MPI) in parallel distributed memory programs. We show examples of this on-going work as well.

  12. Moho Modeling Using FFT Technique

    NASA Astrophysics Data System (ADS)

    Chen, Wenjin; Tenzer, Robert

    2017-04-01

    To improve the numerical efficiency, the Fast Fourier Transform (FFT) technique was facilitated in Parker-Oldenburg's method for a regional gravimetric Moho recovery, which assumes the Earth's planar approximation. In this study, we extend this definition for global applications while assuming a spherical approximation of the Earth. In particular, we utilize the FFT technique for a global Moho recovery, which is practically realized in two numerical steps. The gravimetric forward modeling is first applied, based on methods for a spherical harmonic analysis and synthesis of the global gravity and lithospheric structure models, to compute the refined gravity field, which comprises mainly the gravitational signature of the Moho geometry. The gravimetric inverse problem is then solved iteratively in order to determine the Moho depth. The application of FFT technique to both numerical steps reduces the computation time to a fraction of that required without applying this fast algorithm. The developed numerical producers are used to estimate the Moho depth globally, and the gravimetric result is validated using the global (CRUST1.0) and regional (ESC) seismic Moho models. The comparison reveals a relatively good agreement between the gravimetric and seismic models, with the RMS of differences (of 4-5 km) at the level of expected uncertainties of used input datasets, while without the presence of significant systematic bias.

  13. Techniques of interventional tumor therapy.

    PubMed

    Mahnken, Andreas H; Bruners, Philipp; Günther, Rolf W

    2008-09-01

    The last few years have seen the rapid development of new image-guided interventions for the local treatment of malignant tumors. The goal of this article is to provide an overview of the techniques that are most commonly used today in interventional oncology. Selective literature review on the current state of image-guided interventional techniques for local tumor therapy. While surgery, radiation oncology, and systemic chemotherapy are still the three main pillars of tumor therapy, a broad range of minimally invasive, image-guided techniques for local tumor treatment is now available. These may be categorized as percutaneous injection of a toxic substance, transarterial embolization, thermal ablation, and internal radiotherapy. The choice of treatment depends on the type, location, and size of tumor. The greatest amount of clinical experience to date has been gathered in the treatment of primary and secondary hepatic malignancy, but there are interventional treatment options for virtually all regions of the body. At present, the utility of this form of treatment is limited for very large or multiple tumors; novel therapeutic options for these situations are now being studied. The outcome of treatment depends on a judicious determination of the indication for it. The indication should be established by interdisciplinary consensus after all treatment options have been considered.

  14. Imaging techniques for myocardial inflammation

    SciTech Connect

    O'Connell, J.B.; Henkin, R.E.; Robinson, J.A.

    1986-03-01

    Dilated cardiomyopathy (DC) represents a heterogeneous group of disorders which results in morbidity and mortality in young individuals. Recent evidence suggests that a subset of these patients have histologic evidence of myocarditis which is potentially treatable with immunosuppression. The identification of myocardial inflammation may therefore lead to development of therapeutic regimens designed to treat the cause rather than the effect of the myocardial disease. Ultimately, this may result in improvement in the abysmal prognosis of DC. The currently accepted technique for identification of active myocardial inflammation is endomyocardial biopsy. This technique is not perfect, however, since pathologic standards for the diagnosis of myocarditis have not been established. Furthermore, focal inflammation may give rise to sampling error. The inflammation-avid radioisotope gallium-67 citrate has been used as an adjunct to biopsy improving the yield of myocarditis from 7 percent to 36 percent. Serial imaging correlates well to biopsy results. Future studies are designed to study the applicability of lymphocyte labelling techniques to myocardial inflammatory disease.

  15. Simultaneous multislice (SMS) imaging techniques

    PubMed Central

    Barth, Markus; Breuer, Felix; Koopmans, Peter J.; Poser, Benedikt A.

    2015-01-01

    Simultaneous multislice imaging (SMS) using parallel image reconstruction has rapidly advanced to become a major imaging technique. The primary benefit is an acceleration in data acquisition that is equal to the number of simultaneously excited slices. Unlike in‐plane parallel imaging this can have only a marginal intrinsic signal‐to‐noise ratio penalty, and the full acceleration is attainable at fixed echo time, as is required for many echo planar imaging applications. Furthermore, for some implementations SMS techniques can reduce radiofrequency (RF) power deposition. In this review the current state of the art of SMS imaging is presented. In the Introduction, a historical overview is given of the history of SMS excitation in MRI. The following section on RF pulses gives both the theoretical background and practical application. The section on encoding and reconstruction shows how the collapsed multislice images can be disentangled by means of the transmitter pulse phase, gradient pulses, and most importantly using multichannel receiver coils. The relationship between classic parallel imaging techniques and SMS reconstruction methods is explored. The subsequent section describes the practical implementation, including the acquisition of reference data, and slice cross‐talk. Published applications of SMS imaging are then reviewed, and the article concludes with an outlook and perspective of SMS imaging. Magn Reson Med 75:63–81, 2016. © 2015 The Authors. Magnetic Resonance in Medicine Published by Wiley Periodicals, Inc. on behalf of International Society of Medicine in Resonance. PMID:26308571

  16. Fluid Manipulation Utilizing Electrowetting Techniques

    NASA Astrophysics Data System (ADS)

    Kaiser, Laura; Pyrak-Nolte, Laura

    2014-03-01

    The fraction of the pore space in rock occupied by a given fluid is called saturation. The relationship between saturation and capillary pressure for porous media is hysteretic between imbibition and drainage cycles. If the wetting phase saturation increases, the capillary pressure follows an imbibition curve, and, if the wetting phase saturation decreases, the capillary pressure follows the drainage curve. Due to this hysteresis, researchers have suggested that there is a third variable that should be considered called interfacial area per volume that removes the ambiguity in the capillary pressure - saturation relationship. Before the relationship can be explored in more detail, we first must be able to manipulate the saturation internally rather than externally. We used electrowetting techniques to manipulate the contact angle of a salt water drop. This technique affects the interfacial energy and, therefore, enables manipulation of the contact angles and saturation. Once mastered, the technique could be used to explore the effect of interfacial area per volume on micromodel systems. NSF REU

  17. Simultaneous multislice (SMS) imaging techniques.

    PubMed

    Barth, Markus; Breuer, Felix; Koopmans, Peter J; Norris, David G; Poser, Benedikt A

    2016-01-01

    Simultaneous multislice imaging (SMS) using parallel image reconstruction has rapidly advanced to become a major imaging technique. The primary benefit is an acceleration in data acquisition that is equal to the number of simultaneously excited slices. Unlike in-plane parallel imaging this can have only a marginal intrinsic signal-to-noise ratio penalty, and the full acceleration is attainable at fixed echo time, as is required for many echo planar imaging applications. Furthermore, for some implementations SMS techniques can reduce radiofrequency (RF) power deposition. In this review the current state of the art of SMS imaging is presented. In the Introduction, a historical overview is given of the history of SMS excitation in MRI. The following section on RF pulses gives both the theoretical background and practical application. The section on encoding and reconstruction shows how the collapsed multislice images can be disentangled by means of the transmitter pulse phase, gradient pulses, and most importantly using multichannel receiver coils. The relationship between classic parallel imaging techniques and SMS reconstruction methods is explored. The subsequent section describes the practical implementation, including the acquisition of reference data, and slice cross-talk. Published applications of SMS imaging are then reviewed, and the article concludes with an outlook and perspective of SMS imaging. © 2015 Wiley Periodicals, Inc.

  18. Layout techniques for integrated circuits

    SciTech Connect

    Tsay, C.Y.

    1986-01-01

    Several techniques are presented for solving circuit-layout problems. In particular, a channel-placement algorithm is first introduced to reduce the channel density (d) so that a channel router can complete the routing requirements in fewer tracks. A 4-layer channel-routing model is then formulated so that a general channel routing problem (CRP) with cyclic conflicts and long critical paths can be completed with d/2. Finally, the 4-layer, 2-dimensional switchbox routing problem needed to enhance the channel routing in general circuit layout is investigated from the graph-theoretical viewpoint. The channel-placement technique consists of two phases. Using the principle of decomposition, the initial placement phase effectively reduces the complexity of the problem and, therefore, improves the efficiency of the second phase, which is called the iterative improvement placement. The main feature of this phase is its hill-climbing ability to avoid being trapped at local minima. The combination of these two phases leads to an efficient technique for standard cell placement. To utilize multi-layer technology, a new 4-layer channel routing model is introduced to minimize the channel width of more-generalized CRP's. The 2-dimensional switchbox routing problem is transformed to an equivalent graph-theoretical problem.

  19. Cross spread pupil tracking technique

    NASA Astrophysics Data System (ADS)

    Wolski, Krzysztof; Mantiuk, Radosław

    2016-11-01

    We present a fast and minimum delay algorithm for detecting the pupil center, called the "cross spread" tracking technique. This algorithm is meant for video eye trackers that estimate gaze direction from the position of the pupil center in the captured images. Contrary to other solutions, we do not try to make this technique robust to distractors such as reflections, distortions caused by glasses, or eyelids covering the pupil, but rather we assume eye tracking in stable light conditions. We argue that this approach is useful in many eye tracking applications, such as gaze tracking during psychophysical experiments in stable laboratory conditions, and that this approach can significantly reduce the eye tracker's complexity while maintaining its accuracy and performance. The proposed cross spread technique estimates pupil by tracing rays in horizontal and vertical directions in the image, starting from a point in the pupil region and continuing to the pupil boundary. The found boundary points determine the next starting point and the procedure is iteratively repeated. Parallel processing can be efficiently used enabling accurate pupil center detection in <2 ms on typical laptops. We compare the proposed algorithm to other pupil detection algorithms.

  20. Moho Modeling Using FFT Technique

    NASA Astrophysics Data System (ADS)

    Chen, Wenjin; Tenzer, Robert

    2017-03-01

    To improve the numerical efficiency, the Fast Fourier Transform (FFT) technique was facilitated in Parker-Oldenburg's method for a regional gravimetric Moho recovery, which assumes the Earth's planar approximation. In this study, we extend this definition for global applications while assuming a spherical approximation of the Earth. In particular, we utilize the FFT technique for a global Moho recovery, which is practically realized in two numerical steps. The gravimetric forward modeling is first applied, based on methods for a spherical harmonic analysis and synthesis of the global gravity and lithospheric structure models, to compute the refined gravity field, which comprises mainly the gravitational signature of the Moho geometry. The gravimetric inverse problem is then solved iteratively in order to determine the Moho depth. The application of FFT technique to both numerical steps reduces the computation time to a fraction of that required without applying this fast algorithm. The developed numerical producers are used to estimate the Moho depth globally, and the gravimetric result is validated using the global (CRUST1.0) and regional (ESC) seismic Moho models. The comparison reveals a relatively good agreement between the gravimetric and seismic models, with the RMS of differences (of 4-5 km) at the level of expected uncertainties of used input datasets, while without the presence of significant systematic bias.

  1. NASA standard: Trend analysis techniques

    NASA Technical Reports Server (NTRS)

    1988-01-01

    This Standard presents descriptive and analytical techniques for NASA trend analysis applications. Trend analysis is applicable in all organizational elements of NASA connected with, or supporting, developmental/operational programs. Use of this Standard is not mandatory; however, it should be consulted for any data analysis activity requiring the identification or interpretation of trends. Trend Analysis is neither a precise term nor a circumscribed methodology, but rather connotes, generally, quantitative analysis of time-series data. For NASA activities, the appropriate and applicable techniques include descriptive and graphical statistics, and the fitting or modeling of data by linear, quadratic, and exponential models. Usually, but not always, the data is time-series in nature. Concepts such as autocorrelation and techniques such as Box-Jenkins time-series analysis would only rarely apply and are not included in this Standard. The document presents the basic ideas needed for qualitative and quantitative assessment of trends, together with relevant examples. A list of references provides additional sources of information.

  2. Perioperative Acupuncture and Related Techniques

    PubMed Central

    Chernyak, Grigory V.; Sessler, Daniel I.

    2005-01-01

    Acupuncture and related techniques are increasingly practiced in conventional medical settings, and the number of patients willing to use these techniques is increasing. Despite more than 30 years of research, the exact mechanism of action and efficacy of acupuncture have not been established. Furthermore, most aspects of acupuncture have yet to be adequately tested. There thus remains considerable controversy about the role of acupuncture in clinical medicine. Acupuncture apparently does not reduce volatile anesthetic requirement by a clinically important amount. However, preoperative sedation seems to be a promising application of acupuncture in perioperative settings. Acupuncture may be effective for postoperative pain relief but requires a high level of expertise by the acupuncture practitioner. Acupuncture and related techniques can be used for treatment and prophylaxis of postoperative nausea and vomiting in routine clinical practice in combination with, or as an alternative to, conventional antiemetics when administered before induction of general anesthesia. Summary Statement: The use of acupuncture for perioperative analgesia, nausea and vomiting, sedation, anesthesia, and complications is reviewed. PMID:15851892

  3. Short counseling techniques for busy family doctors.

    PubMed

    Poon, V H

    1997-04-01

    To introduce two short counseling skills for busy family doctors: the BATHE technique and the DIG technique. The BATHE technique indicates five areas for questioning patients who require counseling: background, affect, trouble, handling, and empathy. No research on use of the technique has been published. The DIG technique is the author's modification of the BATHE technique. While the efficacy of counseling in general was validated, more research on the effectiveness on these two techniques needs to be done. Since counseling is an integral part of family practice, family doctors will find these techniques useful. Each is easy to learn and takes less than 15 minutes to complete.

  4. EDITORIAL: Imaging systems and techniques Imaging systems and techniques

    NASA Astrophysics Data System (ADS)

    Yang, Wuqiang; Giakos, George; Nikita, Konstantina; Pastorino, Matteo; Karras, Dimitrios

    2009-10-01

    The papers in this special issue focus on providing the state-of-the-art approaches and solutions to some of the most challenging imaging areas, such as the design, development, evaluation and applications of imaging systems, measuring techniques, image processing algorithms and instrumentation, with an ultimate aim of enhancing the measurement accuracy and image quality. This special issue explores the principles, engineering developments and applications of new imaging systems and techniques, and encourages broad discussion of imaging methodologies, shaping the future and identifying emerging trends. The multi-faceted field of imaging requires drastic adaptation to the rapid changes in our society, economy, environment and technological evolution. There is an urgent need to address new problems, which tend to be either static but complex, or dynamic, e.g. rapidly evolving with time, with many unknowns, and to propose innovative solutions. For instance, the battles against cancer and terror, monitoring of space resources and enhanced awareness, management of natural resources and environmental monitoring are some of the areas that need to be addressed. The complexity of the involved imaging scenarios and demanding design parameters, e.g. speed, signal-to-noise ratio (SNR), specificity, contrast, spatial resolution, scatter rejection, complex background and harsh environments, necessitate the development of a multi-functional, scalable and efficient imaging suite of sensors, solutions driven by innovation, and operation on diverse detection and imaging principles. Efficient medical imaging techniques capable of providing physiological information at the molecular level present another important research area. Advanced metabolic and functional imaging techniques, operating on multiple physical principles, and using high-resolution, high-selectivity nano-imaging methods, quantum dots, nanoparticles, biomarkers, nanostructures, nanosensors, micro-array imaging chips

  5. Simulation verification techniques study. Subsystem simulation validation techniques

    NASA Technical Reports Server (NTRS)

    Duncan, L. M.; Reddell, J. P.; Schoonmaker, P. B.

    1974-01-01

    Techniques for validation of software modules which simulate spacecraft onboard systems are discussed. An overview of the simulation software hierarchy for a shuttle mission simulator is provided. A set of guidelines for the identification of subsystem/module performance parameters and critical performance parameters are presented. Various sources of reference data to serve as standards of performance for simulation validation are identified. Environment, crew station, vehicle configuration, and vehicle dynamics simulation software are briefly discussed from the point of view of their interfaces with subsystem simulation modules. A detailed presentation of results in the area of vehicle subsystems simulation modules is included. A list of references, conclusions and recommendations are also given.

  6. Swept Impact Seismic Technique (SIST)

    USGS Publications Warehouse

    Park, C.B.; Miller, R.D.; Steeples, D.W.; Black, R.A.

    1996-01-01

    A coded seismic technique is developed that can result in a higher signal-to-noise ratio than a conventional single-pulse method does. The technique is cost-effective and time-efficient and therefore well suited for shallow-reflection surveys where high resolution and cost-effectiveness are critical. A low-power impact source transmits a few to several hundred high-frequency broad-band seismic pulses during several seconds of recording time according to a deterministic coding scheme. The coding scheme consists of a time-encoded impact sequence in which the rate of impact (cycles/s) changes linearly with time providing a broad range of impact rates. Impact times used during the decoding process are recorded on one channel of the seismograph. The coding concept combines the vibroseis swept-frequency and the Mini-Sosie random impact concepts. The swept-frequency concept greatly improves the suppression of correlation noise with much fewer impacts than normally used in the Mini-Sosie technique. The impact concept makes the technique simple and efficient in generating high-resolution seismic data especially in the presence of noise. The transfer function of the impact sequence simulates a low-cut filter with the cutoff frequency the same as the lowest impact rate. This property can be used to attenuate low-frequency ground-roll noise without using an analog low-cut filter or a spatial source (or receiver) array as is necessary with a conventional single-pulse method. Because of the discontinuous coding scheme, the decoding process is accomplished by a "shift-and-stacking" method that is much simpler and quicker than cross-correlation. The simplicity of the coding allows the mechanical design of the source to remain simple. Several different types of mechanical systems could be adapted to generate a linear impact sweep. In addition, the simplicity of the coding also allows the technique to be used with conventional acquisition systems, with only minor modifications.

  7. Research Techniques Made Simple: Skin Carcinogenesis Models: Xenotransplantation Techniques.

    PubMed

    Mollo, Maria Rosaria; Antonini, Dario; Cirillo, Luisa; Missero, Caterina

    2016-02-01

    Xenotransplantation is a widely used technique to test the tumorigenic potential of human cells in vivo using immunodeficient mice. Here we describe basic technologies and recent advances in xenotransplantation applied to study squamous cell carcinomas (SCCs) of the skin. SCC cells isolated from tumors can either be cultured to generate a cell line or injected directly into mice. Several immunodeficient mouse models are available for selection based on the experimental design and the type of tumorigenicity assay. Subcutaneous injection is the most widely used technique for xenotransplantation because it involves a simple procedure allowing the use of a large number of cells, although it may not mimic the original tumor environment. SCC cell injections at the epidermal-to-dermal junction or grafting of organotypic cultures containing human stroma have also been used to more closely resemble the tumor environment. Mixing of SCC cells with cancer-associated fibroblasts can allow the study of their interaction and reciprocal influence, which can be followed in real time by intradermal ear injection using conventional fluorescent microscopy. In this article, we will review recent advances in xenotransplantation technologies applied to study behavior of SCC cells and their interaction with the tumor environment in vivo.

  8. Flexible time domain averaging technique

    NASA Astrophysics Data System (ADS)

    Zhao, Ming; Lin, Jing; Lei, Yaguo; Wang, Xiufeng

    2013-09-01

    Time domain averaging(TDA) is essentially a comb filter, it cannot extract the specified harmonics which may be caused by some faults, such as gear eccentric. Meanwhile, TDA always suffers from period cutting error(PCE) to different extent. Several improved TDA methods have been proposed, however they cannot completely eliminate the waveform reconstruction error caused by PCE. In order to overcome the shortcomings of conventional methods, a flexible time domain averaging(FTDA) technique is established, which adapts to the analyzed signal through adjusting each harmonic of the comb filter. In this technique, the explicit form of FTDA is first constructed by frequency domain sampling. Subsequently, chirp Z-transform(CZT) is employed in the algorithm of FTDA, which can improve the calculating efficiency significantly. Since the signal is reconstructed in the continuous time domain, there is no PCE in the FTDA. To validate the effectiveness of FTDA in the signal de-noising, interpolation and harmonic reconstruction, a simulated multi-components periodic signal that corrupted by noise is processed by FTDA. The simulation results show that the FTDA is capable of recovering the periodic components from the background noise effectively. Moreover, it can improve the signal-to-noise ratio by 7.9 dB compared with conventional ones. Experiments are also carried out on gearbox test rigs with chipped tooth and eccentricity gear, respectively. It is shown that the FTDA can identify the direction and severity of the eccentricity gear, and further enhances the amplitudes of impulses by 35%. The proposed technique not only solves the problem of PCE, but also provides a useful tool for the fault symptom extraction of rotating machinery.

  9. Interference techniques in fluorescence microscopy

    NASA Astrophysics Data System (ADS)

    Dogan, Mehmet

    We developed a set of interference-based optical microscopy techniques to study biological structures through nanometer-scale axial localization of fluorescent biomarkers. Spectral self-interference fluorescence microscopy (SSFM) utilizes interference of direct and reflected waves emitted from fluorescent molecules in the vicinity of planar reflectors to reveal the axial position of the molecules. A comprehensive calculation algorithm based on Green's function formalism is presented to verify the validity of approximations used in a far-field approach that describes the emission of fluorescent markers near interfaces. Using the validated model, theoretical limits of axial localization were determined with emphasis given to numerical aperture (NA) dependence of localization uncertainty. SSFM was experimentally demonstrated in conformational analysis of nucleoproteins. In particular, interaction between surface-tethered 75-mer double strand DNA and integration host factor (IHF) protein was probed on Si-SiO2 substrates by determining the axial position of fluorescent labels attached to the free ends of DNA molecules. Despite its sub-nanometer precision axial localization capability, SSFM lacks high lateral resolution due to the low-NA requirement for planar reflectors. We developed a second technique, 4Pi-SSFM, which improves the lateral resolution of a conventional SSFM system by an order of magnitude while achieving nanometer-scale axial localization precision. Using two opposing high-NA objectives, fluorescence signal is interferometrically collected and spectral interference pattern is recorded. Axial position of emitters is found from analysis of the spectra. The 4Pi-SSFM technique was experimentally demonstrated by determining the surface profiles of fabricated glass surfaces and outer membranes of Shigella, a type of Gram-negative bacteria. A further discussion is presented to localize surface O antigen, which is an important oligosaccharide structure in the

  10. Autokinetic word technique and personality.

    PubMed

    Frigon, J Y

    1977-12-01

    24 male subjects were divided into four groups on the basis of their scores on the Eysenck Personality Inventory and were administered the autokinetic word technique test as elaborated by Rechtschaffen and Mednick (1955), with numbers of words and letters reported constituting the response measures. Stable introverts reported significantly more words and letters than stable extraverts; there was no difference between neurotic introverts and neurotic extraverts. On the basis of the large inter-subject variability, the usefulness of the autokinetic-word situation in the investigation of projection is doubted.

  11. Automated medical image segmentation techniques

    PubMed Central

    Sharma, Neeraj; Aggarwal, Lalit M.

    2010-01-01

    Accurate segmentation of medical images is a key step in contouring during radiotherapy planning. Computed topography (CT) and Magnetic resonance (MR) imaging are the most widely used radiographic techniques in diagnosis, clinical studies and treatment planning. This review provides details of automated segmentation methods, specifically discussed in the context of CT and MR images. The motive is to discuss the problems encountered in segmentation of CT and MR images, and the relative merits and limitations of methods currently available for segmentation of medical images. PMID:20177565

  12. Mammalian Cell Tissue Culture Techniques.

    PubMed

    Phelan, Katy; May, Kristin M

    2016-06-01

    Cultured tissues and cells are used extensively in physiological and pharmacological studies. In vitro cultures provide a means of examining cells and tissues without the complex interactions that would be present if the whole organism were studied. A number of special skills are required in order to preserve the structure, function, behavior, and biology of cells in culture. This unit describes the basic skills required to maintain and preserve cell cultures: maintaining aseptic technique, preparing media with the appropriate characteristics, passaging, freezing and storage, recovering frozen stocks, and counting viable cells. © 2016 by John Wiley & Sons, Inc. Copyright © 2016 John Wiley & Sons, Inc.

  13. Research in millimeter wave techniques

    NASA Technical Reports Server (NTRS)

    Mcmillan, R. W.

    1987-01-01

    The areas of millimeter wave (MMW) research include atmospheric propagation and radiometry, advanced MMW component design with emphasis on quasi-optical techniques, and the development of MMW receivers, especially those using subharmonic mixers. Calculations of atmospheric attenuation and radiometric antenna temperature were made in the range 100 to 700 GHz, together with measurements of atmospheric antenna temperature near 95 and 183 GHz. Quasi-optical components designed include lenses, mirrors, and wire grid devices, as well as feedhorns for interference with waveguide components. Subharmonic mixers with state-of-the-art performance at 183 GHz were also developed. Each of these areas of research is summarized.

  14. Fuzzy mathematical techniques with applications

    SciTech Connect

    Kandel, A.

    1986-01-01

    This text presents the basic concepts of fuzzy set theory within a context of real-world applications. The book is self-contained and can be used as a starting point for people interested in this fast growing field as well as by researchers looking for new application techniques. The section on applications includes: Manipulation of knowledge in expert systems; relational database structures; pattern clustering; analysis of transient behavior in digital systems; modeling of uncertainty and search trees. Contents: Fuzzy sets; Possibility theory and fuzzy quantification; Fuzzy functions; Fuzzy events and fuzzy statistics; Fuzzy relations; Fuzzy logics; Some applications; Bibliography.

  15. Techniques for Automated Performance Analysis

    SciTech Connect

    Marcus, Ryan C.

    2014-09-02

    The performance of a particular HPC code depends on a multitude of variables, including compiler selection, optimization flags, OpenMP pool size, file system load, memory usage, MPI configuration, etc. As a result of this complexity, current predictive models have limited applicability, especially at scale. We present a formulation of scientific codes, nodes, and clusters that reduces complex performance analysis to well-known mathematical techniques. Building accurate predictive models and enhancing our understanding of scientific codes at scale is an important step towards exascale computing.

  16. Surgical techniques and infectious disease.

    PubMed

    Story, R D

    1991-10-01

    Dentists are at risk of acquiring blood-borne infectious diseases by accidental inoculation whilst performing oral surgical procedures. These risks have been well discussed in the literature and by most assessments are considered to be minimal. They are, however, very real to those at risk. One response to these risks is to cease practice although many would see this as an extreme response. Another response is to modify surgical techniques in such a way that surgical procedures become safer without also becoming more complicated.

  17. EPR techniques for space biodosimetry

    SciTech Connect

    Haskell, E.; Hayes, R.; Kenner, G.; Sholom, S.; Chumak, V.

    1996-12-31

    Retrospective dosimetry of tooth enamel has become an increasingly complex and difficult discipline to undertake while still attaining accuracy. The paper provides a review of the major obstacles, advances and pertinent phenomenon associated with low level retrospective dosimetry of human tooth enamel. Also covered is the many sources of error in EPR dosimetry, their potential solutions, as well as the different analysis and scanning techniques in use with their prospective pros and cons. Prospective directions for new approaches, methods, and instruments are also reviewed.

  18. Modified Technique For Chemisorption Measurements

    NASA Technical Reports Server (NTRS)

    Schryer, David R.; Brown, Kenneth G.; Schryer, Jacqueline

    1989-01-01

    In measurements of chemisorption of CO on Pt/SnO2 catalyst observed that if small numbers of relatively large volumes of adsorbate gas are passed through sample, very little removal of CO detected. In these cases little or no CO has been chemisorbed on Pt/SnO2. Technique of using large number of small volumes of adsorbate gas to measure chemisorption applicable to many gas/material combinations other than CO on Pt/SnO2. Volume used chosen so that at least 10 percent of adsorbate gas removed during each exposure.

  19. Modelling techniques for jet impingement

    NASA Technical Reports Server (NTRS)

    Haviland, J. K.; Herling, W. W.

    1977-01-01

    A technique for testing scale models for the determination of fluctuating pressure loads due to jet impingement has been investigated using a quarter-scale model of a boilerplate test facility in which a JT-15D engine with a rectangular outer nozzle blows over a small curved airfoil representing the upper-surface of a wing. When model and full-scale spectra of fluctuating surface pressures are reduced to plots of pressure coefficient power-spectral density vs Strouhal number, moderate agreement is obtained, but a shift of spectral peaks is noted. However, when a correction for the ratio of average jet to ambient temperature is applied, the spectral peaks agree.

  20. Infrared techniques for comet observations

    NASA Technical Reports Server (NTRS)

    Hanner, Martha S.; Tokunaga, Alan T.

    1991-01-01

    The infrared spectral region (1-1000 microns) is important for studies of both molecules and solid grains in comets. Infrared astronomy is in the midst of a technological revolution, with the development of sensitive 2D arrays leading to IR cameras and spectrometers with vastly improved sensitivity and resolution. The Halley campaign gave us tantalizing first glimpses of the comet science possible with this new technology, evidenced, for example, by the many new spectral features detected in the infrared. The techniques of photometry, imaging, and spectroscopy are reviewed in this chapter and their status at the time of the Halley observations is described.