Science.gov

Sample records for vibratory stress relief

  1. The relationships between residual stress relaxation and texture development in AZ31 Mg alloys via the vibratory stress relief technique

    SciTech Connect

    Wang, Jia-Siang; Hsieh, Chih-Chun; Lai, Hsuan-Han; Kuo, Che-Wei; Wu, Paxon Ti-Yuan; Wu, Weite

    2015-01-15

    A systematic study of residual stress relaxation and the texture evolution of cold-rolled AZ31 Mg alloys using the vibratory stress relief technique with a simple cantilever beam vibration system was performed using a high-resolution X-ray diffractometer and a portable X-ray residual stress analyzer. The effects of vibrational stress excitation on the surface residual stress distribution and on the texture of pole figures (0002) occurring during the vibratory stress relief were examined. Compared with the effects corresponding to the same alloy under non-vibration condition, it can be observed that the uniform surface residual stress distribution and relaxation of the compressive residual stress in the stress concentration zone were observed rather than all of the residual stresses being eliminated. Furthermore, with an increase in the vibrational aging time, the compressive residual stress, texture density, and (0002) preferred orientation increased first and then decreased. It should be underlined that the vibratory stress relief process for the vibrational aging time of more than 10 min is able to weaken the strong basal textures of AZ31 Mg alloys, which is valuable for enhancement of their formability and is responsible for an almost perfect 3D-Debye–Scherrer ring. - Highlights: • 3D-Debye ring about VSR technique is not discussed in the existing literature. • A newly developed VSR method is suitable for small or thin workpieces. • The cosα method accurately and effectively determines the residual stresses. • The VSR technique is valuable for enhancement of their formability. • The texture and preferred orientation change with the vibrational aging time.

  2. Predicting vibratory stresses from aero-acoustic loads

    NASA Astrophysics Data System (ADS)

    Shaw, Matthew D.

    Sonic fatigue has been a concern of jet aircraft engineers for many years. As engines become more powerful, structures become more lightly damped and complex, and materials become lighter, stiffer, and more complicated, the need to understand and predict structural response to aeroacoustic loads becomes more important. Despite decades of research, vibration in panels caused by random pressure loads, such as those found in a supersonic jet, is still difficult to predict. The work in this research improves on current prediction methods in several ways, in particular for the structural response due to wall pressures induced by supersonic turbulent flows. First, solutions are calculated using time-domain input pressure loads that include shock cells and their interaction with turbulent flow. The solutions include both mean (static) and oscillatory components. Second, the time series of stresses are required for many fatigue assessment counting algorithms. To do this, a method is developed to compute time-dependent solutions in the frequency domain. The method is first applied to a single-degree-of-freedom system. The equations of motion are derived and solved in both the frequency domain and the time domain. The pressure input is a random (broadband) signal representative of jet flow. The method is then applied to a simply-supported beam vibrating in flexure using a line of pressure inputs computed with computational fluid dynamics (CFD). A modal summation approach is used to compute structural response. The coupling between the pressure field and the structure, through the joint acceptance, is reviewed and discussed for its application to more complicated structures. Results from the new method and from a direct time domain method are compared for method verification. Because the match is good and the new frequency domain method is faster computationally, it is chosen for use in a more complicated structure. The vibration of a two-dimensional panel loaded by jet

  3. Effect of residual stress on modal patterns of MEMS vibratory gyroscope

    NASA Astrophysics Data System (ADS)

    Dutta, Shankar; Panchal, Abha; Kumar, Manoj; Pal, Ramjay; Bhan, R. K.

    2016-04-01

    Deep boron diffusion often induces residual stress in bulk micromachined MEMS structures, which may affect the MEMS devices operation. In this study, we studied the modal patterns of MEMS vibratory gyroscope under the residual stress (100 - 1000 MPa). Modal patterns and modal frequencies of the gyro are found to be dependent on the residual stress values. Without any residual stress, the modal frequencies drive and sense modeswere found to be 20.06 kHz and 20.36 kHz respectively. In presence of 450 MPa residual stress, the modal frequencies of the drive and sense modes were changed to 42.75 kHz and 43.07 kHz respectively.

  4. Method for residual stress relief and retained austenite destabilization

    DOEpatents

    Ludtka, Gerard M.

    2004-08-10

    A method using of a magnetic field to affect residual stress relief or phase transformations in a metallic material is disclosed. In a first aspect of the method, residual stress relief of a material is achieved at ambient temperatures by placing the material in a magnetic field. In a second aspect of the method, retained austenite stabilization is reversed in a ferrous alloy by applying a magnetic field to the alloy at ambient temperatures.

  5. 46 CFR 54.30-10 - Method of performing mechanical stress relief.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Method of performing mechanical stress relief. 54.30-10 Section 54.30-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PRESSURE VESSELS Mechanical Stress Relief § 54.30-10 Method of performing mechanical stress relief. (a) The mechanical stress relief shall...

  6. 46 CFR 54.30-10 - Method of performing mechanical stress relief.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Method of performing mechanical stress relief. 54.30-10... PRESSURE VESSELS Mechanical Stress Relief § 54.30-10 Method of performing mechanical stress relief. (a) The mechanical stress relief shall be carried out in accordance with the following stipulations using water...

  7. 46 CFR 54.30-10 - Method of performing mechanical stress relief.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Method of performing mechanical stress relief. 54.30-10... PRESSURE VESSELS Mechanical Stress Relief § 54.30-10 Method of performing mechanical stress relief. (a) The mechanical stress relief shall be carried out in accordance with the following stipulations using water...

  8. FREEZE-FRAME: Fast Action Stress Relief.

    ERIC Educational Resources Information Center

    Childre, Doc Lew

    Recent scientific research has proven that we can, not only manage our stress, we can even prevent it. Ways to achieve stress management are presented in this book. It details a method called FREEZE-FRAME, a process in which individuals mentally stop the chaos that surrounds them and then calmly contemplate their situation. The text opens with an…

  9. Stress-relief cracking of a new ferritic steel

    NASA Astrophysics Data System (ADS)

    Nawrocki, Jesse Gerald

    The mechanism of stress-relief cracking in the coarse-grained heat-affected zone (CGHAZ) of low-alloy ferritic steels was studied through a tempering study, stress-relaxation testing, and detailed microstructural characterization. A new ferritic alloy steel, HCM2S, was used as the model system. Common 2.25Cr-1 Mo steel, which is susceptible to stress-relief cracking, was used for comparison to HCM2S. The CGHAZ was simulated using Gleeble techniques. A dense distribution of small tungsten-rich carbides within the prior austenite grains induced secondary hardening in the CGHAZ of HCM2S. The CGHAZ of 2.25Cr-1 Mo steel exhibited secondary hardening due to the intragranular precipitation of many Fe-rich M3C carbides. The hardness of HCM2S was more stable at longer times and high temperatures than 2.25Cr-1 Mo steel due to the intragranular precipitation of small W and V-rich carbides. The CGHAZs of HCM2S and 2.25Cr-1 Mo steel were susceptible to stress-relief cracking between 575 and 725°C. HCM2S exhibited C-curve behavior with respect to the time to failure as a function of post-weld heat treatment (PWHT) temperature. No segregation of tramp elements to prior austenite grain boundaries was detected in HCM2S. Both intergranular and intragranular carbide precipitation controlled the stress-relief cracking behavior. The amount of intergranular failure increased with test temperature due to the increasing amounts of Fe-rich M3C carbides at the prior austenite grain boundaries. These carbides acted as cavity nucleation sites. The cavities coalesced to form microcracks along prior austenite grain boundaries. Eventually, the remaining uncracked areas could not support the load and failed by ductile rupture. The balance of intergranular and intragranular carbide precipitation resulted in the C-curve behavior. The nose of the C-curve occurred at 675°C. The intragranular regions were strong because of a dense distribution of W/Fe-rich carbides, but the prior austenite grain

  10. Social buffering: relief from stress and anxiety

    PubMed Central

    Kikusui, Takefumi; Winslow, James T; Mori, Yuji

    2006-01-01

    Communication is essential to members of a society not only for the expression of personal information, but also for the protection from environmental threats. Highly social mammals have a distinct characteristic: when conspecific animals are together, they show a better recovery from experiences of distress. This phenomenon, termed ‘social buffering’, has been found in rodents, birds, non-human primates and also in humans. This paper reviews classical findings on social buffering and focuses, in particular, on social buffering effects in relation to neuroendocrine stress responses. The social cues that transmit social buffering signals, the neural mechanisms of social buffering and a partner's efficacy with respect to social buffering are also detailed. Social contact appears to have a very positive influence on the psychological and the physiological aspects of social animals, including human beings. Research leading towards further understanding of the mechanisms of social buffering could provide alternative medical treatments based on the natural, individual characteristics of social animals, which could improve the quality of life. PMID:17118934

  11. 46 CFR 54.30-10 - Method of performing mechanical stress relief.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Method of performing mechanical stress relief. 54.30-10 Section 54.30-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PRESSURE VESSELS Mechanical Stress Relief § 54.30-10 Method of performing mechanical stress relief. (a)...

  12. 46 CFR 54.30-10 - Method of performing mechanical stress relief.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Method of performing mechanical stress relief. 54.30-10 Section 54.30-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PRESSURE VESSELS Mechanical Stress Relief § 54.30-10 Method of performing mechanical stress relief. (a)...

  13. Feeling Stressed? Stress Relief Might Help Your Health

    MedlinePlus

    ... new tasks if they are putting you into overload. Think positive. Note what you’ve accomplished at ... TALK (1-800-273-8255). Stress: NIH Health Information Fact Sheet on Stress Psychological Stress and Cancer ...

  14. High voltage bushing having weathershed and surrounding stress relief collar

    DOEpatents

    Cookson, Alan H.

    1981-01-01

    A high voltage electric bushing comprises a hollow elongated dielectric weathershed which encloses a high voltage conductor. A collar formed of high voltage dielectric material is positioned over the weathershed and is bonded thereto by an interface material which precludes moisture-like contaminants from entering between the bonded portions. The collar is substantially thicker than the adjacent weathershed which it surrounds, providing relief of the electric stresses which would otherwise appear on the outer surface of the weathershed. The collar may include a conductive ring or capacitive foil to further relieve electric stresses experienced by the bushing.

  15. Estimates of heat stress relief needs for Holstein dairy cows.

    PubMed

    Berman, A

    2005-06-01

    Estimates of environmental heat stress are required for heat stress relief measures in cattle. Heat stress is commonly assessed by the temperature-humidity index (THI), the sum of dry and wet bulb temperatures. The THI does not include an interaction between temperature and humidity, although evaporative heat loss increases with rising air temperature. Coat, air velocity, and radiation effects also are not accounted for in the THI. The Holstein dairy cow is the primary target of heat stress relief, followed by feedlot cattle. Heat stress may be estimated for a variety of conditions by thermal balance models. The models consist of animal-specific data (BW, metabolic heat production, tissue and coat insulation, skin water loss, coat depth, and minimal and maximal tidal volumes) and of general heat exchange equations. A thermal balance simulation model was modified to adapt it for Holstein cows by using Holstein data for the animal characteristics in the model, and was validated by comparing its outputs to experimental data. Model outputs include radiant, convective, skin evaporative, respiratory heat loss and rate of change of body temperature. Effects of milk production (35 and 45 kg/d), hair coat depth (3 and 6 mm), air temperature (20 to 45 degrees C), air velocity (0.2 to 2.0 m/s), air humidity (0.8 to 3.9 kPa), and exposed body surface (100, 75, and 50%) on thermal balance outputs were examined. Environmental conditions at which respiratory heat loss attained approximately 50% of its maximal value were defined as thresholds for intermediate heat stress. Air velocity increased and humidity significantly decreased threshold temperatures, particularly at higher coat depth. The effect of air velocity was amplified at high humidity. Increasing milk production from 35 to 45 kg/d decreased threshold temperature by 5 degrees C. In the lying cow, the lower air velocity in the proximity of body surface and the smaller exposed surface markedly decrease threshold

  16. Stress and Stress Relief in the Educational Research Classroom.

    ERIC Educational Resources Information Center

    Wilson, Vicki A.

    Factors that increase stress and those that decrease stress were studied with 33 graduate students in an introductory educational research course. Participants completed the Statistical Anxiety Rating Scale (STARS) (R. Cruse, R. Cash, and D. Bolton, 1985) and were asked to rate their anxiety daily during the 4 weeks of the class. The instructor's…

  17. 46 CFR 154.655 - Stress relief for independent tanks type C.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Stress relief for independent tanks type C. 154.655... Equipment Construction § 154.655 Stress relief for independent tanks type C. For a design temperature colder... stress relieved by post-weld heat treatment under § 54.25-7 of this chapter or by mechanical...

  18. 46 CFR 154.655 - Stress relief for independent tanks type C.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Stress relief for independent tanks type C. 154.655... Equipment Construction § 154.655 Stress relief for independent tanks type C. For a design temperature colder... stress relieved by post-weld heat treatment under § 54.25-7 of this chapter or by mechanical...

  19. 46 CFR 154.655 - Stress relief for independent tanks type C.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Stress relief for independent tanks type C. 154.655... Equipment Construction § 154.655 Stress relief for independent tanks type C. For a design temperature colder... stress relieved by post-weld heat treatment under § 54.25-7 of this chapter or by mechanical...

  20. 46 CFR 154.655 - Stress relief for independent tanks type C.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Stress relief for independent tanks type C. 154.655... Equipment Construction § 154.655 Stress relief for independent tanks type C. For a design temperature colder... stress relieved by post-weld heat treatment under § 54.25-7 of this chapter or by mechanical...

  1. 46 CFR 154.655 - Stress relief for independent tanks type C.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Stress relief for independent tanks type C. 154.655... Equipment Construction § 154.655 Stress relief for independent tanks type C. For a design temperature colder... stress relieved by post-weld heat treatment under § 54.25-7 of this chapter or by mechanical...

  2. Comparison of Stress Relief Procedures for Cryogenic Aluminum Mirrors

    NASA Technical Reports Server (NTRS)

    Ohl, Raymond G.; Barthelmy, Michael P.; Zewari, S. Wahid; Toland, Ronald; Mink, Ronald; Mentzell, J. Eric; Greenhouse, Matthew A.; McMann, Joseph C.; Hylan, Jason; Hagopian, John G.; Krebs, Carolyn (Technical Monitor)

    2002-01-01

    The Infrared Multi-Object Spectrograph (IRMOS) is a facility instrument for the Kitt Peak National Observatory Mayall Telescope (3.8 meter) and an engineering prototype for a potential design for the Next Generation Space Telescope/Multi-Object Spectrograph. IRMOS is a low-to mid-resolution (R = lambda/delta-lambda = 300-3800), near-IR (0.8-2.5 micron) spectrograph which produces simultaneous spectra of approximately 100 objects in its 2.8 x 2.0 arcmin field of view using a commercial MEMS multimirror array device. The instrument operating temperature is 80 K and the design is athermal --- the optical bench and mirrors are machined from aluminum 6061-T651. In spite of its baseline mechanical stress relief, aluminum 6061-T651 harbors some residual stress, which, unless relieved during fabrication, may relieve and distort mirror figure to unacceptable levels at the operating temperature. Other cryogenic instruments using aluminum mirrors for both ground-based and space IR astronomy have employed a variety of heat treatment formulae, with mixed results. We present the results of a test program designed to empirically determine the best stress relief procedure for the IRMOS mirrors. Identical test mirrors with spherical and flat optical prescriptions are processed with five different heat treatment formulae from the literature and compared to samples with out any additional processing. After figuring via diamond turning, the mirrors are tested for figure error and radius of curvature at room temperature and at 80 K for several thermal cycles. The heat treatment procedure for the mirrors that yielded the least and most repeatable change in figure error and radius is applied to the IRMOS mirror blanks. We correlate the results of our optical testing with heat treatment and metallographic data.

  3. Surface Residual Stresses in Ti-6Al-4V Friction Stir Welds: Pre- and Post-Thermal Stress Relief

    NASA Astrophysics Data System (ADS)

    Edwards, P.; Ramulu, M.

    2015-09-01

    The purpose of this study was to determine the residual stresses present in titanium friction stir welds and if a post-weld thermal stress relief cycle would be effective in minimizing those weld-induced residual stresses. Surface residual stresses in titanium 6Al-4V alloy friction stir welds were measured in butt joint thicknesses ranging from 3 to 12 mm. The residual stress states were also evaluated after the welds were subjected to a post-weld thermal stress relief cycle of 760 °C for 45 min. High (300-400 MPa) tensile residual stresses were observed in the longitudinal direction prior to stress relief and compressive residual stresses were measured in the transverse direction. After stress relief, the residual stresses were decreased by an order of magnitude to negligible levels.

  4. Decompaction mechanism of deep crystalline rocks under stress relief

    NASA Astrophysics Data System (ADS)

    Gorbatsevich, F. F.

    2003-07-01

    Within a geological massif in a stable geodynamical situation contacts on the grain boundaries in polycrystalline rocks at great depths are continuous and firm. The stress release of those rocks during drilling and excavation to the surface is accompanied by their disintegration (decompaction). The reason for the decompaction is generation of microcracks during stress release due to the difference between the elastic moduli of crystalline grains at their contacts. The mechanism of decompaction may occur not only in polymineral but in polycrystalline rocks as well. The method of decompaction evaluation of deep crystalline rocks under stress relief is presented. According to the calculations the initial manifestation of the decompaction effect in biotite gneisses will occur when they are extracted from the deep range of 0.8-1 km. The first microcracks arise on the grain borders between quartz-biotite and oligoclase-biotite. It is shown that the uplift of gneiss-granite varities of the rocks cut by the Kola superdeep borehole from depths exceeding 13-15 km will be possible in a form of separate mineral grains. Practical importance of the presented method is in an opportunity to evaluate the level of excavated decompaction. The method allow estimating the depth, from which the rock will be extracted only in a sludge form.

  5. Experimental and analytical evaluation of the effects of simulated engine inlets on the blade vibratory stresses of the SR-3 model prop-fan

    NASA Technical Reports Server (NTRS)

    Bansal, Prem N.

    1985-01-01

    A cooperative wind tunnel test program, referred to as GUN-3, had been conducted previously to assess the effect of inlet configuration and location on the inlet face pressure recovery and inlet drag in the presence of a high-speed advanced turboprop. These tests were conducted with the inlets located just downstream of the SR-3 model Prop-Fan, a moderately swept, eight-bladed 62.2 cm (24.5 inch) diameter advanced, high-speed turboprop model fabricated from titanium. During these tests, two blades of the SR-3 model Prop-Fan were strain gaged to measure the vibratory blade stresses occurring during the inlet aerodynamic test program. The purpose of the effort reported herein was to reduce and analyze the test results related to the vibratory strain gage measurements obtained. Three inlet configurations had been tested. These were: (1) single scoop, (2) twin scoop, and (3) annular. Each of the three inlets was tested at a position just behind the rotor. The single scoop inlet was also tested at a position further aft. Tests were also done without an inlet. These results emphasize the importance of avoiding critical speeds in the continuous operating range.

  6. Thermal stress-relief treatments for 2219 aluminum alloy are evaluated

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Evaluation of three thermal stress relief treatments for 2219 aluminum alloy in terms of their effect on residual stress, mechanical properties, and stress corrosion resistance. The treatments are post aging and stress relieving fullscale and subscale parts formed in the aged T81 condition, and aging subscale parts formed in the unaged T31 condition.

  7. Residual stresses in a multi-pass weld in an austenitic stainless steel plate before and after thermal stress relief

    SciTech Connect

    Spooner, S.; Wang, X.L.; Hubbard, C.R.; David, S.A.

    1994-06-01

    Changes in residual stresses due to thermal stress relief were determined in a welded 1/2 in. thick 304 stainless steel plate from two residual stress maps determined with the neutron diffraction technique. The 304 stainless plate was made from two 6 {times} 12 {times} 1/2 in. pieces joined along the length by a gas tungsten arc welding process. Multi-pass welds were made with a semiautomatic welding machine employing cold-wire feed of type 308 stainless steel filler alloy. The thermal stress relief treatment consisted of heating to 1150 F, holding for one hour at temperature and then air cooling. Strain components were measured along the weld direction (longitudinal), perpendicular to the weld line in the plate (transverse), and normal to the plate. Measurements were confined to the plane bisecting the weld at the center of the plate. The strain components were converted to stresses assuming that the measured strains were along the principal axes of the strain tensor. Parameters used in the calculation were E=224 GPa and v=0.25. As-welded longitudinal stresses are compressive in the base metal and become strongly tensile through the heat affected zone and into the fusion zone. The transverse stresses follow the longitudinal trend but with a lower magnitude while the normal stresses are small throughout. The stress relief treatment reduced the magnitudes of all the stresses. In the weld zone the longitudinal stress was lowered by 30% and the spatial range of residual stresses was reduced as well.

  8. Vibratory gyroscopic sensors

    NASA Astrophysics Data System (ADS)

    Fox, C. H. J.; Hardie, D. J. W.

    The paper describes the principles of operation of vibratory gyroscopic sensors based on simple oscillators, balanced oscillators, and vibrating shells with particular emphasis on the third type. Error mechanisms are discussed and the relative merits of the three types are considered leading to the conclusion that vibrating shell sensors offer substantial advantages over the other types in terms of their immunity to external vibration and the relatively weak interaction between the basic sensing vibration of the shell and the instrument mounting.

  9. Advanced turboprop vibratory characteristics

    NASA Technical Reports Server (NTRS)

    Srinivasan, A. V.; Fulton, G. B.

    1984-01-01

    The assembly of SR5 advanced turboprop blades to develop a structural dynamic data base for swept props is reported. Steady state blade deformation under centrifugal loading and vibratory characteristics of the rotor assembly were measured. Vibration was induced through a system of piezoelectric crystals attached to the blades. Data reduction procedures are used to provide deformation, mode shape, and frequencies of the assembly at predetermined speeds.

  10. Stress-relief displacements induced by drilling--applications to holographic measurements of in situ stress

    SciTech Connect

    Ahrens, T.J.; Smither, C.L.

    1992-04-24

    The holographic stressmeter is an instrument which has been developed at Caltech to allow determination of the complete stress tensor from in situ borehole measurements. The stressmeter uses double-exposure holographic interferometry to record the displacements induced by the drilling of a small sidehole into the borehole wall. The local stresses, which are the result of the far-field stresses, concentrated at the borehole, cause deformation of the surface of the borehole wall in the vicinity of the sidehole. The first part of this study uses a thin infinite elastic plate subjected to plane stress at infinity to model the displacements at the borehole wall. However, the existence of some holograms which were difficult to model closely led us to examine the validity of this model. In order to investigate the problem further, we performed a two-dimensional finite element analysis for an elastic box with a terminated hole. We varied the dimensions of the hole to see what effect the radius and depth of the hole might have on the displacements. The plate model predicts that the depth of the hole should have no effect on the horizontal components of displacement, but the finite element results show that the magnitude of both components of the displacement depends on the depth of the sidehole. After considering these results, we developed a new model for the analysis of stress-relief displacements, following the work of Youngdahl and Sternberg (1965). For holes with a depth-to-diameter ratio greater than unity, the simple plane stress elastic plate solution breaks down and does not adequately model the displacements at the surface of the body and near the hole. Since these are the areas most critical to calculate accurately with the holographic technique, the revised model does a better job of fitting the observed data.

  11. Stress-relief displacements induced by drilling: Applications to holographic measurements of in situ stress

    NASA Astrophysics Data System (ADS)

    Ahrens, T. J.; Smither, C. L.

    1992-04-01

    The holographic stressmeter is an instrument which has been developed at Caltech to allow the determination of the complete stress tensor from in situ borehole measurements. The stressmeter uses double-exposure holographic interferometry to record the displacements induced by the drilling of a small sidehole into the borehole wall. The local stresses, which are the result of the far-field stresses concentrated at the borehole, cause deformation of the surface of the borehole wall in the vicinity of the sidehole. The first part of this study uses a thin infinite elastic plate subjected to plane stress at infinity to model the displacements at the borehole wall. However, the existence of some holograms which were difficult to model closely led us to examine the validity of this model. In order to investigate the problem further, we performed a two-dimensional finite element analysis for an elastic box with a terminated hole. We varied the dimensions of the hole to see what effect the radius and depth of the hole might have on the displacements. The plate model predicts that the depth of the hole should have no effect on the horizontal components of displacement, but the finite element results show that the magnitude of both components of the displacement depends on the depth of the sidehole. After considering these results, we developed a new model for the analysis of stress-relief displacements, following the work of Youngdahl and Sternberg (1965). For holes with a depth-to-diameter ratio greater than unity, the simple plane stress elastic plate solution breaks down and does not adequately model the displacements at the surface of the body and near the hole. Since these are the areas most critical to calculate accurately with the holographic technique, the revised model does a better job of fitting the observed data.

  12. Cloverleaf Vibratory Microgyroscope with Integrated Post

    NASA Technical Reports Server (NTRS)

    Tang, Tony K.; Gutierrez, Roman; Roger, Damien

    2003-01-01

    A modified design and fabrication sequence has been devised to improve the performance of a cloverleaf vibratory microgyroscope that includes an axial rod or post rigidly attached to the center of the cloverleaf structure. The basic concepts of cloverleaf vibratory microgyroscopes, without and with rods or posts, were described in two prior articles in NASA Tech Briefs, Vol. 21, No. 9 (September 1997): Micromachined Planar Vibratory Microgyroscopes (NPO-19713), page 68 and Planar Vibratory Microgyroscope: Alternative Configuration (NPO-19714), page 70. As described in more detail in the second-mentioned prior article, the cloverleaf-shaped structure and the rod or post are parts of a vibratory element that senses rotation via the effect of the Coriolis force upon its vibrations. Heretofore, the posts for devices of this type have been fabricated separately, then assembled manually onto the cloverleaf structures. The resulting imperfections in the assembled units have given rise to asymmetric stresses in the cloverleaf structures and, consequently, to changes in resonant frequencies of vibration and in shapes of vibration modes. These changes, in turn, have caused variations in performance among nominally identical devices. The modified design provides for the fabrication of the upper half of the post as an integral part of the cloverleaf structure; this is accomplished by reactive-ion etching of a single-piece half-post-and-cloverleaf structure from a wafer of silicon. The lower half of the post and a baseplate are also a single piece made by reactive-ion etching from a wafer of silicon. The two pieces are bonded together (see figure) by a thermal-compression metal-to-metal bonding technique to form a cloverleaf gyroscope with an integrated post structure..

  13. Effectiveness of a Stress-Relief Initiative for Primary Caregivers of Adolescents with Intellectual Disability

    ERIC Educational Resources Information Center

    Hu, Jung; Lin, Jin-Ding; Yen, Chia-Feng; Loh, Ching-Hui; Hsu, Shang-Wei; Lin, Lan-Ping; Wu, Sheng-Ru

    2010-01-01

    Background: This study provides a perspective on the mental health status and analyses the effectiveness of a stress-relief program for primary caregivers of adolescents with intellectual disability (ID). Method: Seventy-seven primary caregivers of people with ID were recruited (intervention group, n = 31; non-intervention group, n = 46) to the…

  14. Laughter and Stress Relief in Cancer Patients: A Pilot Study

    PubMed Central

    Kim, S. H.; Kim, Y. H.; Kim, H. J.

    2015-01-01

    The purpose of this study was to examine the effect of a therapeutic laughter program and the number of program sessions on anxiety, depression, and stress in breast cancer patients. A randomized controlled trial was conducted involving 31 patients who received four sessions of therapeutic laughter program comprised and 29 who were assigned to the no-program control group. Scores for anxiety, depression, and stress were measured using an 11-point numerical rating scale. While no change was detected in the control group, the program group reported reductions of 1.94, 1.84, and 2.06 points for anxiety, depression, and stress, respectively (p < 0.01, p < 0.01, and p < 0.01). Scores decreased significantly after the first therapeutic laughter session (p < 0.05, p < 0.01, and p < 0.01). As the therapeutic laughter program was effective after only a single session in reducing anxiety, depression, and stress in breast cancer patients, it could be recommended as a first-line complementary/alternative therapy. PMID:26064177

  15. Statistical modeling implicates neuroanatomical circuit mediating stress relief by 'comfort' food.

    PubMed

    Ulrich-Lai, Yvonne M; Christiansen, Anne M; Wang, Xia; Song, Seongho; Herman, James P

    2016-07-01

    A history of eating highly palatable foods reduces physiological and emotional responses to stress. For instance, we have previously shown that limited sucrose intake (4 ml of 30 % sucrose twice daily for 14 days) reduces hypothalamic-pituitary-adrenocortical (HPA) axis responses to stress. However, the neural mechanisms underlying stress relief by such 'comfort' foods are unclear, and could reveal an endogenous brain pathway for stress mitigation. As such, the present work assessed the expression of several proteins related to neuronal activation and/or plasticity in multiple stress- and reward-regulatory brain regions of rats after limited sucrose (vs. water control) intake. These data were then subjected to a series of statistical analyses, including Bayesian modeling, to identify the most likely neurocircuit mediating stress relief by sucrose. The analyses suggest that sucrose reduces HPA activation by dampening an excitatory basolateral amygdala-medial amygdala circuit, while also potentiating an inhibitory bed nucleus of the stria terminalis principle subdivision-mediated circuit, resulting in reduced HPA activation after stress. Collectively, the results support the hypothesis that sucrose limits stress responses via plastic changes to the structure and function of stress-regulatory neural circuits. The work also illustrates that advanced statistical methods are useful approaches to identify potentially novel and important underlying relationships in biological datasets. PMID:26246177

  16. The Mechanism of Residual Stress Relief for Various Tin Grain Structures

    NASA Astrophysics Data System (ADS)

    Yu, Cheng-Fu; Hsieh, Ker-Chang

    2010-08-01

    A pure tin deposition process was developed with various tin grain structures to study tin whisker formation. Samples were tested for 4000 h to examine whisker formation, grain structures, and intermetallic formation using a focused ion beam (FIB). The lateral side of the FIB-cut cavity displayed tin protrusions after 6 days. These phenomena, along with the growth of tin whiskers and/or hillocks, could illustrate the residual stress relief behavior of various tin grain structures. In full columnar structures, whiskers formed normal to the deposition surface and relieved most of the stress. In contrast, stress relaxation in semicolumnar and random structures is highly likely to occur, and proceeds rapidly in the direction parallel to the deposition surface after only a few days. In comparing mixed grain structures, it is apparent that stress is more likely to be rapidly relieved within structures with fewer grain boundaries.

  17. Analysis of rotor vibratory loads using higher harmonic pitch control

    NASA Technical Reports Server (NTRS)

    Quackenbush, Todd R.; Bliss, Donald B.; Boschitsch, Alexander H.; Wachspress, Daniel A.

    1992-01-01

    Experimental studies of isolated rotors in forward flight have indicated that higher harmonic pitch control can reduce rotor noise. These tests also show that such pitch inputs can generate substantial vibratory loads. The modification is summarized of the RotorCRAFT (Computation of Rotor Aerodynamics in Forward flighT) analysis of isolated rotors to study the vibratory loading generated by high frequency pitch inputs. The original RotorCRAFT code was developed for use in the computation of such loading, and uses a highly refined rotor wake model to facilitate this task. The extended version of RotorCRAFT incorporates a variety of new features including: arbitrary periodic root pitch control; computation of blade stresses and hub loads; improved modeling of near wake unsteady effects; and preliminary implementation of a coupled prediction of rotor airloads and noise. Correlation studies are carried out with existing blade stress and vibratory hub load data to assess the performance of the extended code.

  18. Posttraumatic stress disorder in disaster relief workers following direct and indirect trauma exposure to Ground Zero.

    PubMed

    Zimering, Rose; Gulliver, Suzy B; Knight, Jeffrey; Munroe, James; Keane, Terence M

    2006-08-01

    The present study compared rates of posttraumatic stress disorder (PTSD) in relief workers at the World Trade Center collapse from two sources: direct exposure to the disaster site and indirect exposure through survivor narratives. Standardized clinical interviews for PTSD were conducted with 109 relief workers 6-8 months after the September 11th terrorist attacks. Rates of acute PTSD from direct and indirect exposure to traumatic stressors were 6.4% and 4.6%, respectively. The findings suggest that indirect exposures can lead to PTSD even when Criterion A1 of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-Text Revision (DSM-IV-TR; American Psychiatric Association, 2000, p. 463), i.e., "experienced by a family member or other close associate" is not met. Further research is necessary to define precisely the parameters of indirect traumatic exposure that may be linked to the development of PTSD. PMID:16929511

  19. Microcracking during stress-relief of polycrystalline ice formed at high pressure

    NASA Astrophysics Data System (ADS)

    Meglis, Irene L.; Gagnon, R. E.; Young, R. P.

    To study microcracking in a brittle material in response to stress-relief, samples of polycrystalline ice were frozen under hydrostatic pressures up to 19 MPa and subsequently decompressed. Eight cylindrical samples (approximately 56 mm in diameter and 120 mm long) were made by freezing a slurry of crushed ice and degassed water inside a clear Teflon jacket. Four additional tests were done by reloading samples which were previously unloaded, allowing them to re-equilibrate, and then unloading again. Tests were filmed through windows in the confining cell. Acoustic emissions were monitored in some samples. When the stress was released, intense cracking occurred for approximately 0.4 seconds and then tapered off. Thin sections showed that the stress-relief cracks were approximately equal to the facet size (<5 mm), were primarily along grain boundaries, and were distributed throughout the samples with no obvious preferred orientation. Within a few hours of unloading, grain boundaries became cloudy, possibly a result of air trapped at the grain surfaces. Preliminary results from further tests indicate that this air plays a significant role in crack nucleation.

  20. VIBRATORY SPIRAL BLANCHER-COOLER

    EPA Science Inventory

    The objective of the demonstration project was to test the commercial feasibility of the vibratory spiral blancher-cooler, a newly designed steam blancher and air cooler that previous small scale tests showed could reduce the wasteload and energy consumption of preparing vegetabl...

  1. The Meta-Lax method of stress reduction in welds. Phase 2 study

    SciTech Connect

    Smith, S.M.

    1992-07-31

    This study is the second phase of ongoing research into the mechanics and feasibility of using the Meta-Lax method of vibratory stress relief in place of thermal methods of stress relief. The first phase of this research revealed results that were similar to, and even superior to those achieved using thermal methods. The testing here was designed to eliminate the effects of interbead tempering by utilizing single pass bead-on-plate welds only. A metallurgical explanation for the success of the Meta-Lax method was not found. No significant structure or chemical changes were noted when used with ASTM A36 or AISI 4140 materials, and the phenomena noted in phase I was apparently due to interbead tempering. The theory of accelerated aging has been proposed and studies exist which observed dislocation motion as a result of vibratory treatment. It is evident that the vibratory stress relief system does not impart sufficient energy to bring about the magnitude of change seen with thermal methods. however the physical improvement is a reality, and vibratory methods should be evaluated further.

  2. The Meta-Lax method of stress reduction in welds. [ASTM A36; AISI 4140

    SciTech Connect

    Smith, S.M.

    1992-07-31

    This study is the second phase of ongoing research into the mechanics and feasibility of using the Meta-Lax method of vibratory stress relief in place of thermal methods of stress relief. The first phase of this research revealed results that were similar to, and even superior to those achieved using thermal methods. The testing here was designed to eliminate the effects of interbead tempering by utilizing single pass bead-on-plate welds only. A metallurgical explanation for the success of the Meta-Lax method was not found. No significant structure or chemical changes were noted when used with ASTM A36 or AISI 4140 materials, and the phenomena noted in phase I was apparently due to interbead tempering. The theory of accelerated aging has been proposed and studies exist which observed dislocation motion as a result of vibratory treatment. It is evident that the vibratory stress relief system does not impart sufficient energy to bring about the magnitude of change seen with thermal methods. however the physical improvement is a reality, and vibratory methods should be evaluated further.

  3. Hydrologic effects of stress-relief fracturing in an Appalachian Valley

    USGS Publications Warehouse

    Wyrick, Granville G.; Borchers, James W.

    1981-01-01

    being formed from stress relief. As stress-relief fractures have been described in other valleys of the Appalachian Plateaus, the same aquifer conditions may exist in those valleys.

  4. Functions of health fatalism: fatalistic talk as face saving, uncertainty management, stress relief and sense making.

    PubMed

    Keeley, Bethany; Wright, Lanelle; Condit, Celeste M

    2009-07-01

    Much research on fatalism assumes that fatalistic statements represent a global outlook that conflicts with belief in the efficacy of health behaviours. Other scholars have suggested a more contextual approach, suggesting that fatalism fulfils personal and social functions. This study analyses 96 in-depth lay interviews in the US, most with low-income members of the general public, about four diseases: heart disease, lung cancer, diabetes and depression. Within these interviews, fatalistic statements always occurred alongside statements endorsing the utility of behaviours for protecting health. This usage pattern suggests that these statements may have useful functions, rather than being simply a repudiation of the utility of health choices. We examine four functions that are suggested by previous researchers or by the participants' comments: stress relief, uncertainty management, sense making and (less strongly) face saving. As these themes indicate, individuals often make fatalistic statements to express an understanding of locally or broadly limiting factors for health efficacy, including genes, spiritual agents, prior behaviours, personality, and other factors. PMID:19392939

  5. Vibratory tactile display for textures

    NASA Technical Reports Server (NTRS)

    Ikei, Yasushi; Ikeno, Akihisa; Fukuda, Shuichi

    1994-01-01

    We have developed a tactile display that produces vibratory stimulus to a fingertip in contact with a vibrating tactor matrix. The display depicts tactile surface textures while the user is exploring a virtual object surface. A piezoelectric actuator drives the individual tactor in accordance with both the finger movement and the surface texture being traced. Spatiotemporal display control schemes were examined for presenting the fundamental surface texture elements. The temporal duration of vibratory stimulus was experimentally optimized to simulate the adaptation process of cutaneous sensation. The selected duration time for presenting a single line edge agreed with the time threshold of tactile sensation. Then spatial stimulus disposition schemes were discussed for representation of other edge shapes. As an alternative means not relying on amplitude control, a method of augmented duration at the edge was investigated. Spatial resolution of the display was measured for the lines presented both in perpendicular and parallel to a finger axis. Discrimination of texture density was also measured on random dot textures.

  6. GEC Ferranti piezo vibratory gyroscope

    NASA Technical Reports Server (NTRS)

    Nuttall, J. D.

    1993-01-01

    Prototypes of a piezo-electric vibratory angular rate transducer (gyroscope) (PVG) have been constructed and evaluated. The construction is on the lines suggested by Burdess. The sensitive element is a cylinder of radially poled piezo-electric ceramic. The cylinder is metallized inside and out, and the outer metallization is divided into eight electrodes. The metallization on the inside is earthed. A phase locked loop, using pairs of the electrodes, causes the cylinder to vibrate in one of its two fundamental, degenerate modes. In the presence of rotation, some of the vibration is coupled into the outer mode. This can be detected, or suppressed with a closed-up technique and provides a measure of rotation rate. The gyroscope provides a number of advantages over rotating mass and optical instruments: low size and mass, lower power consumption, potentially high reliability, potentially good dormancy, low cost and high maximum rate.

  7. Snoring-Induced Vibratory Angioedema

    PubMed Central

    Kalathoor, Ipe

    2015-01-01

    Patient: Female, 70 Final Diagnosis: Snoring induced vibratory angioedema Symptoms: Swelling of tongue • roof of mouth and throat • multiple episodes at night Medication: — Clinical Procedure: Continuous positive airway pressure therapy Specialty: Allergology Objective: Rare disease Background: Vibratory angioedema (VA) is a rare physical urticaria, with symptoms of itching and swelling of the skin or mucosa when it is exposed to vibration. Avoidance of vibration is the best way to manage this condition. This case report will assist physicians to diagnose this rare condition. Here, a previously unpublished potential successful treatment modality is being presented, with good symptom control, along with some photographs taken during an acute attack. A literature review points towards potential undiagnosed cases. Case Report: A 70-year-old woman had multiple emergency department visits for tongue and throat swelling over 3 years. The episodes always happened at night. Detailed history elicited some episodes of itching and swelling of hands when driving as well as significant snoring while sleeping. Physical examination was unremarkable except for morbid obesity. Complement factor 4 and C1esterase inhibitor level were within normal limits. A tentative diagnosis of angioedema induced by oropharyngeal vibration from snoring was made. A sleep study confirmed sleep apnea with severe snoring. After CPAP (continuous positive airway pressure) treatment, she had successful symptom control. Conclusions: Snoring-induced VA is very likely an under-diagnosed condition in the community. The typical history is the key to the diagnosis. This condition could be confirmed by vibration test or by the resolution of symptoms with elimination of vibration. Effective symptom control is possible by avoidance of oropharyngeal vibration from snoring with the administration of CPAP therapy, making it a potential novel indication for this condition. PMID:26437464

  8. Non-inertial calibration of vibratory gyroscopes

    NASA Technical Reports Server (NTRS)

    Gutierrez, Roman C. (Inventor); Tang, Tony K. (Inventor)

    2003-01-01

    The electrostatic elements already present in a vibratory gyroscope are used to simulate the Coriolis forces. An artificial electrostatic rotation signal is added to the closed-loop force rebalance system. Because the Coriolis force is at the same frequency as the artificial electrostatic force, the simulated force may be introduced into the system to perform an inertial test on MEMS vibratory gyroscopes without the use of a rotation table.

  9. The hand and environment (3)--physiological changes of digital functions in two age groups studied by vibratory stimulations and a cold water immersion.

    PubMed

    Suzuki, K; Ijichi, M; Kobayashi, Y; Matsuki, T; Ito, K; Kamogawa, M; Matsushita, T; Kotani, K; Seki, A; Tanaka, H; Kawamura, K

    1982-02-25

    Skin temperature, vibratory sensibility and pinch strength of the hand were recorded continuously in 20 healthy adults through two vibratory stress tests (32 Hz and 125 Hz) and a cold water (10 degrees C) immersion (for 10 min) test in a climatic chamber (20 degrees C, 50% humidity). As a stressor to the hand, the immersion was the most effective and the vibrator stress at 32 Hz was next. As a detector for function of the hand, vibratory sensibility at 125 Hz was proved to be the most valuable and the digital temperature was the next. As to aging, the mature age group showed low vibratory sensibilities at 63 Hz, higher digital temperatures, stronger pinch strengths, and quicker recoveries after the stress tests. Along the passage of time after entering the chamber, the vibratory sensibilities and the pinch strengths did not show any changes. However, the digital temperatures became continuously lower. PMID:7077112

  10. Quasi-static intergranular cracking in a Cu-Sn alloy: An analog of stress relief cracking of steels

    SciTech Connect

    Barrera, E.V.; Menyhard, M.; Bika, D.; Rothman, B.; McMahon, C.J. Jr.

    1991-01-01

    Intergranular cracking in a laboratory-made Cu-8wt%Sn alloy at 265 to 300{degree}C in vacuum was studied in order to explore the hypothesis that this could serve as an analog to the brittle mode of stress-relief cracking in steels and to test the mechanism proposed earlier to explain that phenomenon. This mechanism involves the stress-induced intergranular penetration along grain boundaries of a surface-adsorbed embrittling element. Sulfur is the active element in this regard in steels, and tin was envisioned as playing the same role in Cu-Sn alloys. Auger spectroscopy was used to confirm earlier reports of the surface activity of tin and to determine the segregation kinetics in the present polycrystals; no other elements were found to segregate to surfaces to any significant degree in the present alloy. Crack growth measurements showed that intergranular cracking occurs in an intermittent manner at an average rate on the order of 0.1 {mu}m/sec over a range of crack length. Crack initiation was found to be remarkably sensitive to the stress intensity, implying the existence of a threshold. The fracture appearance in the regions of slow crack growth was similar to that observed in steels undergoing stress-relief cracking at 500--600{degree}C. It was concluded that the quasi-static intergranular cracking in the steels and in the Cu-Sn alloy represent two aspects of the same generic phenomenon and that the proposed mechanism of stress-induced intergranular impurity penetration is valid. It is believed that liquid-and solid-metal embrittlement are closely related to the type of intergranular cracking described here.

  11. Quasi-static intergranular cracking in a Cu-Sn alloy: An analog of stress relief cracking of steels

    SciTech Connect

    Barrera, E.V.; Menyhard, M.; Bika, D.; Rothman, B.; McMahon, C.J. Jr.

    1991-12-31

    Intergranular cracking in a laboratory-made Cu-8wt%Sn alloy at 265 to 300{degree}C in vacuum was studied in order to explore the hypothesis that this could serve as an analog to the brittle mode of stress-relief cracking in steels and to test the mechanism proposed earlier to explain that phenomenon. This mechanism involves the stress-induced intergranular penetration along grain boundaries of a surface-adsorbed embrittling element. Sulfur is the active element in this regard in steels, and tin was envisioned as playing the same role in Cu-Sn alloys. Auger spectroscopy was used to confirm earlier reports of the surface activity of tin and to determine the segregation kinetics in the present polycrystals; no other elements were found to segregate to surfaces to any significant degree in the present alloy. Crack growth measurements showed that intergranular cracking occurs in an intermittent manner at an average rate on the order of 0.1 {mu}m/sec over a range of crack length. Crack initiation was found to be remarkably sensitive to the stress intensity, implying the existence of a threshold. The fracture appearance in the regions of slow crack growth was similar to that observed in steels undergoing stress-relief cracking at 500--600{degree}C. It was concluded that the quasi-static intergranular cracking in the steels and in the Cu-Sn alloy represent two aspects of the same generic phenomenon and that the proposed mechanism of stress-induced intergranular impurity penetration is valid. It is believed that liquid-and solid-metal embrittlement are closely related to the type of intergranular cracking described here.

  12. How Do You Spell Relief? Alleviating Job Stress Caused by Organizations and Executives.

    ERIC Educational Resources Information Center

    Ginsburg, Sigmund G.

    1991-01-01

    College business officers should examine whether they and their institutions are practicing stress-inducing activities, and modify current practice to reduce stress on employees. Stresses can originate in the organizational framework, managerial style, or manager personality. Review of individual and organizational actions possible causing stress…

  13. Effect of angular inflow on the vibratory response of a counter-rotating propeller

    NASA Technical Reports Server (NTRS)

    Turnberg, J. E.; Brown, P. C.

    1985-01-01

    This report presents the results of a propeller vibratory stress survey on the Fairey Gannet aircraft aimed at giving an assessment of the difference in vibratory response between single and counter-rotating propeller operation in angular inflow. The survey showed that counter-rotating operation of the propeller had the effect of increasing the IP response of the rear propeller by approximately 25 percent over comparable single-rotation operation while counter-rotating operation did not significantly influence the IP response of the front propeller.

  14. Influence of Temperature and Time of Post-weld Heat Treatment on Stress Relief in an 800-mm-Thick Steel Weldment

    NASA Astrophysics Data System (ADS)

    Mitra, Abhishek; Siva Prasad, N.; Janaki Ram, G. D.

    2016-04-01

    Ferritic steel weldments are invariably post-weld heat treated for relieving the residual stresses. However, the long duration of post-weld heat treatment (PWHT) required for very thick weldments can adversely affect the mechanical properties and fracture toughness. Thus, there is a need to establish the relative importance of temperature and time of PWHT with respect to stress relief. Accordingly, in the present work, the phenomenon of stress relief (due to PWHT) in an 800-mm-thick steel weldment was investigated using finite element analysis and the results were validated against experimental measurements. An analytical study was also carried out to determine the relative influence of temperature and time of PWHT on stress relief. It was found that time of PWHT plays a more significant role in case of relatively lower PWHT temperatures. It was also found that, for a given value of Hollomon parameter, different combinations of PWHT temperature and time can be employed to achieve the same level of stress relief. A mathematical relationship has been established between Hollomon parameter and magnitude of residual stress after PWHT. It has been shown that residual stress is a monotonically decreasing function of the Hollomon parameter.

  15. Vibratory finishing as a decontamination process

    SciTech Connect

    McCoy, M.W.; Arrowsmith, H.W.; Allen, R.P.

    1980-10-01

    The major objective of this research is to develop vibratory finishing into a large-scale decontamination technique that can economicaly remove transuranic and other surface contamination from large volumes of waste produced by the operation and decommissioning of retired nuclear facilities. The successful development and widespread application of this decontamination technique would substantially reduce the volume of waste requiring expensive geologic disposal. Other benefits include exposure reduction for decontamination personnel and reduced risk of environmental contamination. Laboratory-scale studies showed that vibratory finishing can rapidly reduce the contamination level of transuranic-contaminated stainless steel and Plexiglas to well below the 10-nCi/g limit. The capability of vibratory finishing as a decontamination process was demonstrated on a large scale. The first decontamination demonstration was conducted at the Hanford N-Reactor, where a vibratory finisher was installed to reduce personnel exposure during the summer outage. Items decontaminated included fuel spacers, process-tube end caps, process-tube inserts, pump parts, ball-channel inspection tools and miscellaneous hand tools. A second demonstration is currently being conducted in the decontamination facility at the Hanford 231-Z Building. During this demonstration, transuranic-contaminated material from decommissioned plutonium facilities is being decontaminated to <10 nCi/g to minimize the volume of material that will require geologic disposal. Items that are being decontaminated include entire glove boxes, process-hood structural material and panels, process tanks, process-tank shields, pumps, valves and hand tools used during the decommissioning work.

  16. DISASTER RELIEF FOR THE JAPANESE EARTHQUAKE-TSUNAMI OF 2011: STRESS REDUCTION THROUGH THE TRANSCENDENTAL MEDITATION® TECHNIQUE.

    PubMed

    Yoshimura, Mitsunobu; Kurokawa, Etsuko; Noda, Takayuki; Hineno, Koji; Tanaka, Yasuo; Kawai, Yuji; Dillbeck, Michael C

    2015-08-01

    This study examined changes in self-reported stress symptoms after instruction in the Transcendental Meditation(®) technique among 171 residents of two cities (Sendai and Ishinomaki) directly affected by the 2011 Japan earthquake and tsunami disaster compared with 326 non-disaster Tokyo participants previously tested before and after learning the technique and a no-treatment control group (n = 68). The participants completed a rating checklist of mental and physical symptoms. Disaster area participants who learned the Transcendental Meditation(®) technique in contrast to controls showed a significant drop in total symptom score from pre-test to post-test (effect size = -1.09). Results were comparable for an ordinal measure of symptom intensity. The findings suggest the potential value of this procedure for relief from disaster trauma. PMID:26226492

  17. Stress relief may promote the evolution of greater phenotypic plasticity in exotic invasive species: a hypothesis

    PubMed Central

    Huang, Qiao Q; Pan, Xiao Y; Fan, Zhi W; Peng, Shao L

    2015-01-01

    Invasion ecologists have often found that exotic invaders evolve to be more plastic than conspecific populations from their native range. However, an open question is why some exotic invaders can even evolve to be more plastic given that there may be costs to being plastic. Investigation into the benefits and costs of plasticity suggests that stress may constrain the expression of plasticity (thereby reducing the benefits of plasticity) and exacerbate the costs of plasticity (although this possibility might not be generally applicable). Therefore, evolution of adaptive plasticity is more likely to be constrained in stressful environments. Upon introduction to a new range, exotic species may experience more favorable growth conditions (e.g., because of release from natural enemies). Therefore, we hypothesize that any factors mitigating stress in the introduced range may promote exotic invaders to evolve increased adaptive plasticity by reducing the costs and increasing the benefits of plasticity. Empirical evidence is largely consistent with this hypothesis. This hypothesis contributes to our understanding of why invasive species are often found to be more competitive in a subset of environments. Tests of this hypothesis may not only help us understand what caused increased plasticity in some exotic invaders, but could also tell us if costs (unless very small) are more likely to inhibit the evolution of adaptive plasticity in stressful environments in general. PMID:25859323

  18. TEM investigations on the effect of chromium content and of stress relief treatment on precipitation in Alloy 82

    NASA Astrophysics Data System (ADS)

    Sennour, M.; Chaumun, E.; Crépin, J.; Duhamel, C.; Gaslain, F.; Guerre, C.; de Curières, I.

    2013-11-01

    Nickel-base alloys are widely used in nuclear Pressurized Water Reactors (PWRs). Most of them have been found susceptible to Stress Corrosion Cracking (SCC) in nominal PWR primary water. The time to initiation depends on the material and is longer for weld metals than for Alloy 600. This study will focus on Alloy 82, which is used in Dissimilar Metal Welds (DMWs). In service, DMWs are either in the as-welded state or have undergone a stress relief treatment. Previous SCC studies showed that the heat treatment reduces significantly the SCC susceptibility of the weld. In this context, this study focuses on the microstructure characterization of the weld in the as-welded state and in the heat-treated state. As chromium content is also a key factor for the SCC susceptibility, welds with low chromium content and medium chromium content were studied. The lower SCC susceptibility of the heat-treated welds was attributed to intergranular Cr23C6 resulting from a combined effect of heat treatment and chromium and carbon contents. These intergranular carbides could explain the better behavior of Alloy 82, compared to other nickel-base alloys.

  19. Residual stress relief due to fatigue in tetragonal lead zirconate titanate ceramics

    SciTech Connect

    Hall, D. A.; Mori, T.; Comyn, T. P.; Ringgaard, E.; Wright, J. P.

    2013-07-14

    High energy synchrotron XRD was employed to determine the lattice strain {epsilon}{l_brace}111{r_brace}and diffraction peak intensity ratio R{l_brace}200{r_brace}in tetragonal PZT ceramics, both in the virgin poled state and after a bipolar fatigue experiment. It was shown that the occurrence of microstructural damage during fatigue was accompanied by a reduction in the gradient of the {epsilon}{l_brace}111{r_brace}-cos{sup 2} {psi} plot, indicating a reduction in the level of residual stress due to poling. In contrast, the fraction of oriented 90 Degree-Sign ferroelectric domains, quantified in terms of R{l_brace}200{r_brace}, was not affected significantly by fatigue. The change in residual stress due to fatigue is interpreted in terms of a change in the average elastic stiffness of the polycrystalline matrix due to the presence of inter-granular microcracks.

  20. Relief of Residual Stress in Streamline Tie Rods by Heat Treatment

    NASA Technical Reports Server (NTRS)

    Pollard, R E; Reinhart, Fred M

    1941-01-01

    About two-thirds of the residual stress in cold-worked SAE 1050 steel tie rods was relieved by heating 30 minutes at 600 degrees Fahrenheit. Cold-worked austenitic stainless-steel tie rods could be heated at temperatures up to 1000 degrees Fahrenheit without lowering the important physical properties. The corrosion resistance, in laboratory corrosion test, of straight 18:8 and titanium-treated 18:8 materials appeared to be impaired after heating at temperatures above 800 degrees or 900 degrees fahrenheit. Columbium-treated and molybdenum-treated 18:8 steel exhibited improved stability over a wide range of temperatures. Tie rods of either material could be heated 30 minutes with safety at any temperature up to 1000 degrees Fahrenheit. At this temperature most of the residual stress would be relieved.

  1. Continuous Tuning and Calibration of Vibratory Gyroscopes

    NASA Technical Reports Server (NTRS)

    Hayworth, Ken

    2003-01-01

    A method of control and operation of an inertial reference unit (IRU) based on vibratory gyroscopes provides for continuously repeated cycles of tuning and calibration. The method is intended especially for application to an IRU containing vibratory gyroscopes that are integral parts of microelectromechanical systems (MEMS) and that have cloverleaf designs, as described in several previous NASA Tech Briefs articles. The method provides for minimization of several measures of spurious gyroscope output, including zero-rate offset (ZRO), angle random walk (ARW), and rate drift. These benefits are afforded both at startup and thereafter during continuing operation, in the presence of unknown rotation rates and changes in temperature. A vibratory gyroscope contains a precision mechanically resonant structure containing two normal modes of vibration nominally degenerate in frequency and strongly coupled via a Coriolis term. In the case of the cloverleaf design MEMS gyro, these normal modes of vibration are plate rocking modes. The rocking motion of the plate is described by giving two angles, theta(sub 1) and theta(sub 2). A proof mass consisting of a post orthogonal to the plate ensures a high degree of Coriolis coupling of vibratory energy from one mode into the other under inertial rotation. The plate is driven and sensed capacitively across a few-microns-wide gap, and the normal mode frequencies can be tuned electrostatically by DC voltages applied across this gap. In order to sense rotation, the resonator plate is caused to rock in the theta(sub 1) direction, then any small motions in the theta(sub 2) direction are sensed, rebalanced, and interpreted as inertial rotation. In this scenario, the "drive" has been assigned to the theta(sub 1) direction, and the "sense" has been assigned to the theta(sub 2) direction.

  2. Vibratory pumping of a free fluid stream

    DOEpatents

    Merrigan, M.A.; Woloshun, K.A.

    1990-11-13

    A vibratory fluid pump is described having a force generator for generating asymmetric periodic waves or oscillations connected to one end of one or more fluid conveyance means, such as filaments. The opposite ends of the filaments are connected to springs. Fluid introduced onto the filaments will traverse along the filaments according to the magnitude of the positive and negative excursions of the periodic waves or oscillations, and can be recovered from the filaments. 3 figs.

  3. Vibratory pumping of a free fluid stream

    DOEpatents

    Merrigan, Michael A.; Woloshun, Keith A.

    1990-01-01

    A vibratory fluid pump having a force generator for generating asymmetric periodic waves or oscillations connected to one end of one or more fluid conveyance means, such as filaments. The opposite ends of the filaments are connected to springs. Fluid introduced onto the filaments will traverse along the filaments according to the magnitude of the positive and negative excursions of the periodic waves or oscillations, and can be recovered from the filaments.

  4. Stress-relief displacements induced by drilling--applications to holographic measurements of in situ stress. Final technical report, August 15, 1988--August 14, 1990

    SciTech Connect

    Ahrens, T.J.; Smither, C.L.

    1992-04-24

    The holographic stressmeter is an instrument which has been developed at Caltech to allow determination of the complete stress tensor from in situ borehole measurements. The stressmeter uses double-exposure holographic interferometry to record the displacements induced by the drilling of a small sidehole into the borehole wall. The local stresses, which are the result of the far-field stresses, concentrated at the borehole, cause deformation of the surface of the borehole wall in the vicinity of the sidehole. The first part of this study uses a thin infinite elastic plate subjected to plane stress at infinity to model the displacements at the borehole wall. However, the existence of some holograms which were difficult to model closely led us to examine the validity of this model. In order to investigate the problem further, we performed a two-dimensional finite element analysis for an elastic box with a terminated hole. We varied the dimensions of the hole to see what effect the radius and depth of the hole might have on the displacements. The plate model predicts that the depth of the hole should have no effect on the horizontal components of displacement, but the finite element results show that the magnitude of both components of the displacement depends on the depth of the sidehole. After considering these results, we developed a new model for the analysis of stress-relief displacements, following the work of Youngdahl and Sternberg (1965). For holes with a depth-to-diameter ratio greater than unity, the simple plane stress elastic plate solution breaks down and does not adequately model the displacements at the surface of the body and near the hole. Since these are the areas most critical to calculate accurately with the holographic technique, the revised model does a better job of fitting the observed data.

  5. How does the stressed out ER find relief during virus infection?

    PubMed

    Verchot, Jeanmarie

    2016-04-01

    The endoplasmic reticulum and Golgi network (ERGN) is vital to most cellular biosynthetic processes. Many positive strand RNA viruses depend upon the ERGN for replication, maturation, and egress. Viruses induce changes in ER architecture and stimulate fatty acid synthesis to create environments that can scaffold replication complexes, plant virus movement complexes, or virion maturation. Potato virus X (PVX) and Turnip mosaic virus (TuMV) each encode small membrane binding proteins that embed in the ERGN and activate the unfolded protein response (UPR). The UPR ensures ERGN homeostasis in the face of environmental assaults that could negatively impact the biosynthetic functions of the ERGN. This article explores the relationship between ER stress, the UPR, and membrane synthesis occurring during virus infection. PMID:26871502

  6. Vibratory Regime Classification of Infant Phonation

    PubMed Central

    Buder, Eugene H.; Chorna, Lesya B.; Oller, D. Kimbrough; Robinson, Rebecca B.

    2008-01-01

    Infant phonation is highly variable in many respects, including the basic vibratory patterns by which the vocal tissues create acoustic signals. Previous studies have identified the regular occurrence of non-modal phonation types in normal infant phonation. The glottis is like many oscillating systems that, because of non-linear relationships among the elements, may vibrate in ways representing the deterministic patterns classified theoretically within the mathematical framework of non-linear dynamics. The infant’s pre-verbal vocal explorations present such a variety of phonations that it may be possible to find effectively all the classes of vibration predicted by non-linear dynamic theory. The current report defines acoustic criteria for an important subset of such vibratory regimes, and demonstrates that analysts can be trained to reliably use these criteria for a classification that includes all instances of infant phonation in the recorded corpora. The method is thus internally comprehensive in the sense that all phonations are classified, but it is not exhaustive in the sense that all vocal qualities are thereby represented. Using the methods thus developed, this study also demonstrates that the distributions of these phonation types vary significantly across sessions of recording in the first year of life, suggesting developmental changes. The method of regime classification is thus capable of tracking changes that may be indicative of maturation of the mechanism, the learning of categories of phonatory control, and the possibly varying use of vocalizations across social contexts. PMID:17509829

  7. Cyclical Stress Field Switching and (Total?) Relief of Fault Shear Stress Recorded in Quartz Vein Systems Hosted by Proterozoic Strike-Slip Faults, Mt Isa, Australia

    NASA Astrophysics Data System (ADS)

    Sibson, R. H.; Begbie, M. J.; Ghisetti, F. C.; Blenkinsop, T. G.

    2003-12-01

    slip increments. A preliminary interpretation is that the differently oriented systematic vein-sets reflect changing orientations of the local stress field at different stages of the earthquake stress cycle. Minimum compressional stress oblique to the fault through the interseismic interval alternates with minimum compression oriented subperpendicular to the fault immediately postfailure, suggesting that each slip episode was accompanied by near-total relief of shear stress along the fault. The presence of amethystine quartz, open-space filling textures, and calcite-quartz intergrowths in the vein sets are consistent with hydrothermal precipitation occurring within 1-2 km of the former ground surface. Consequently, it is not yet clear whether these extensive vein systems developed under hydrostatic or overpresssured fluid conditions.

  8. Making Precise Resonators for Mesoscale Vibratory Gyroscopes

    NASA Technical Reports Server (NTRS)

    Yang, Eui-Hyeok

    2004-01-01

    An alternative approach to the design and fabrication of vibratory gyroscopes is founded on the use of fabrication techniques that yield best results in the mesoscopic size range, which is characterized by overall device dimensions of the order of a centimeter. This approach stands in contradistinction to prior approaches in (1) the macroscopic size range (the size range of conventional design and fabrication, characterized by overall device dimensions of many centimeters) and (2) the microscopic size range [the size range of microelectromechanical systems (MEMS), characterized by overall device dimensions of the order of a millimeter or less]. The mesoscale approach offers some of the advantage of the MEMS approach (sizes and power demands smaller than those of the macroscale approach) and some of the advantage of the macroscale approach (the possibility of achieving relative dimensional precision greater than that of the MEMS approach). Relative dimensional precision is a major issue in the operation of a vibratory gyroscope. The heart of a vibratory gyroscope is a mechanical resonator that is required to have a specified symmetry in a plane orthogonal to the axis about which rotation is to be measured. If the resonator could be perfectly symmetrical, then in the absence of rotation, a free vibration of the resonator could remain fixed along any orientation relative to its housing; that is, the gyroscope could exhibit zero drift. In practice, manufacturing imprecision gives rise to some asymmetry in mass, flexural stiffness or dissipation, resulting in a slight drift or beating motion of an initial vibration pattern that cannot be distinguished from rotation. In the mesoscale approach, one exploits the following concepts: For a given amount of dimensional error generated in manufacturing, the asymmetry and hence the rate-of-rotation drift of the gyroscope can be reduced by increasing the scale. The decrease in asymmetry also reduces coupling of vibrations to the

  9. Parametrically disciplined operation of a vibratory gyroscope

    NASA Technical Reports Server (NTRS)

    Shcheglov, Kirill V. (Inventor); Hayworth, Ken J. (Inventor); Challoner, A. Dorian (Inventor); Peay, Chris S. (Inventor)

    2008-01-01

    Parametrically disciplined operation of a symmetric nearly degenerate mode vibratory gyroscope is disclosed. A parametrically-disciplined inertial wave gyroscope having a natural oscillation frequency in the neighborhood of a sub-harmonic of an external stable clock reference is produced by driving an electrostatic bias electrode at approximately twice this sub-harmonic frequency to achieve disciplined frequency and phase operation of the resonator. A nearly symmetric parametrically-disciplined inertial wave gyroscope that can oscillate in any transverse direction and has more than one bias electrostatic electrode that can be independently driven at twice its oscillation frequency at an amplitude and phase that disciplines its damping to zero in any vibration direction. In addition, operation of a parametrically-disciplined inertial wave gyroscope is taught in which the precession rate of the driven vibration pattern is digitally disciplined to a prescribed non-zero reference value.

  10. Fast Laser Shutters With Low Vibratory Disturbances

    NASA Technical Reports Server (NTRS)

    Brinza, David; Moore, Donald; Hochberg, Eric; Radey, Tom; Chen, Albert

    2005-01-01

    A prototype vacuum-compatible, fast-acting, long-life shutter unit that generates very little vibratory disturbance during switching is reviewed. This is one of a number of shutters designed to satisfy requirements specific to an experiment, to be performed aboard a spacecraft in flight, in which laser beams must be blocked rapidly and completely, without generating a vibratory disturbance large enough to adversely affect the power and frequency stability of the lasers. Commercial off-the-shelf laboratory shutter units -- typically containing electromagnet-coil-driven mechanisms -- were found not to satisfy the requirements because they are not vacuum-compatible, their actuators engage in uncompensated motions that generate significant vibrations, and their operational lifetimes are too short. Going beyond the initial outerspace application, the present vacuum-compatible, fast-acting, long-life shutter units could also be used in terrestrial settings in which there are requirements for their special characteristics. In designing these shutter units, unbalanced, electromagnetically driven mechanisms were replaced with balanced mechanisms that include commercial piezoelectric bending actuators. In each shutter unit, the piezoelectric bending actuators are configured symmetrically as opposing cantilever beams within a housing that contains integral mounts for lenses that focus a laser beam to a waist at the shutter location. In operation, the laser beam is blocked by titanium blades bonded near the free ends of the piezoelectric benders. The benders are driven by shaped electrical pulses with a maximum voltage differential of less than 60 V. Preliminary measurements indicate that rise and fall times are less than 1 ms.

  11. Research on Bell-Shaped Vibratory Angular Rate Gyro's Character of Resonator

    PubMed Central

    Su, Zhong; Fu, Mengyin; Li, Qing; Liu, Ning; Liu, Hong

    2013-01-01

    Bell-shaped vibratory angular rate gyro (abbreviated as BVG) is a new type Coriolis vibratory gyro that was inspired by Chinese traditional clocks. The resonator fuses based on a variable thickness axisymmetric multicurved surface shell. Its characteristics can directly influence the performance of BVG. The BVG structure not only has capabilities of bearing high overload, high impact and, compared with the tuning fork, vibrating beam, shell and a comb structure, but also a higher frequency to overcome the influence of the disturbance of the exterior environment than the same sized hemispherical resonator gyroscope (HRG) and the traditional cylinder vibratory gyroscope. It can be widely applied in high dynamic low precision angular rate measurement occasions. The main work is as follows: the issue mainly analyzes the structure and basic principle, and investigates the bell-shaped resonator's mathematical model. The reasonable structural parameters are obtained from finite element analysis and an intelligent platform. Using the current solid vibration gyro theory analyzes the structural characteristics and principles of BVG. The bell-shaped resonator is simplified as a paraboloid of the revolution mechanical model, which has a fixed closed end and a free opened end. It obtains the natural frequency and vibration modes based on the theory of elasticity. The structural parameters are obtained from the orthogonal method by the research on the structural parameters of the resonator analysis. It obtains the modal analysis, stress analysis and impact analysis with the chosen parameters. Finally, using the turntable experiment verifies the gyro effect of the BVG. PMID:23575033

  12. Prediction of turbine blade vibratory response due to upstream vane distress

    SciTech Connect

    Panovsky, J.; Carson, S.M.

    1998-07-01

    Turbine blades and vanes operate in a hostile environment, which leads to deterioration of these components over time. This paper describes detailed calculations to predict the vibratory response of a high-pressure turbine blade due to the excitation produced by a single distressed upstream vane in a modern turbofan engine. The approach includes detailed computational fluid dynamics (CFD) analysis of the steady flowfield produced by the distressed vane, Fourier decomposition of the flow variables to determine the harmonic content, unsteady CFD analysis to determine the resulting vibratory response of the blade, and crack propagation analysis to determine blade life. Predictions of vibratory stress and threshold crack size are summarized as functions of vane distress level. The results, which indicate that this type of vane distress can indeed be a significant excitation source for the blades, are shown to be in good agreement with engine experience. The method provides, for the first time, a quantitative approach to setting limits for acceptable levels of vane distress in the field.

  13. Drumlin relief

    NASA Astrophysics Data System (ADS)

    Spagnolo, Matteo; Clark, Chris D.; Hughes, Anna L. C.

    2012-06-01

    Drumlin relief is a key parameter for testing predictions of models of drumlin formation. Although this metric is commonly described in textbooks as being of the order of a few tens of metres, our critical review of the literature suggests an average value of about 13 m, but with much uncertainty. Here we investigate a large sample of drumlins (25,848) mapped from a high resolution digital terrain model of Britain, which allowed the identification of extremely shallow drumlins. Results indicate that most drumlins have a relief between 0.5 and 40 m (with a surprisingly low average value of only 7.1 m) a mode of 3.5-4 m, and with 41% of all drumlins characterized by a relief < 5 m. Drumlin relief is found to never exceed 7% of the width and is positively correlated with this parameter, possibly indicating that drumlins need a large base to stand against the flow of the ice. Drumlin relief is also positively correlated with the length, which shows that drumlins do not grow in length by redistributing sediments from their summits to their downflow (lee) end, as previously hypothesised.

  14. Vertical-plane pendulum absorbers for minimizing helicopter vibratory loads

    NASA Technical Reports Server (NTRS)

    Amer, K. B.; Neff, J. R.

    1974-01-01

    The use of pendulum dynamic absorbers mounted on the blade root and operating in the vertical plane to minimize helicopter vibratory loads was discussed. A qualitative description was given of the concept of the dynamic absorbers and some results of analytical studies showing the degree of reduction in vibratory loads attainable are presented. Operational experience of vertical plane dynamic absorbers on the OH-6A helicopter is also discussed.

  15. The Stress-Relief Cracking Susceptibility of a New Ferritic Steel - Part I: Single-Pass Heat-Affected Zone Simulations

    SciTech Connect

    NAWROCKI,J.G.; DUPONT,J.N.; ROBINO,CHARLES V.; MARDER,A.R.

    1999-12-15

    The stress-relief cracking susceptibility of single-pass welds in a new ferritic steel, HCM2S, has been evaluated and compared to 2.25Cr-1Mo steel using Gleeble techniques. Simulated coarse-grained heat-affected zones (CGHAZ) were produced under a range of energy inputs and tested at various post-weld heat treatment (PWHT) temperatures. Both alloys were tested at a stress of 325 MPa. The 2.25 Cr-1Mo steel was also tested at 270 MPa to normalize for the difference in yield strength between the two materials. Light optical and scanning electron microscopy were used to characterize the CGHAZ microstructure. The ''as-welded'' CGHAZ of each alloy consisted of lath martensite or bainite and had approximately equal prior austenite grain sizes. The as-welded hardness of the 2.25Cr-1Mo steel CGHAZ was significantly higher than that of the HCM2S alloy. Over the range studied energy input had no effect on the as-welded microstructure or hardness of either alloy. The energy input also had no effect on the stress-relief cracking susceptibility of either material. Both alloys failed intergranularly along prior austenite grain boundaries under all test conditions. The 2.25Cr-1Mo steel samples experienced significant macroductility and some microductility when tested at 325 MPa. The ductility decreased significantly when tested at 270 MPa but was still higher that than of HCM2S at each test condition. The time to failure decreased with increasing PWHT Temperature for each material. There was no significant difference in the times to failure between the two materials. Varying energy input and stress had no effect on the time-to failure. The ductility, as measured by reduction in are% increased with increasing PWHT temperature for 2.25 Cr-1Mo steel tested at both stresses. However, PWHT temperature had no effect on the ductility of HCM2S. The hardness of the CGHAZ for 2.25Cr-1Mo steel decreased significantly after PWHT, but remained constant for HCM2S. The differences in stress-relief

  16. A novel acoustic-vibratory multimodal duet.

    PubMed

    Rajaraman, Kaveri; Godthi, Vamsy; Pratap, Rudra; Balakrishnan, Rohini

    2015-10-01

    The communication strategy of most crickets and bushcrickets typically consists of males broadcasting loud acoustic calling songs, while females perform phonotaxis, moving towards the source of the call. Males of the pseudophylline bushcricket species Onomarchus uninotatus produce an unusually low-pitched call, and we found that the immediate and most robust response of females to the male acoustic call was a bodily vibration, or tremulation, following each syllable of the call. We hypothesized that these bodily oscillations might send out a vibrational signal along the substrate on which the female stands, which males could use to localize her position. We quantified these vibrational signals using a laser vibrometer and found a clear phase relationship of alternation between the chirps of the male acoustic call and the female vibrational response. This system therefore constitutes a novel multimodal duet with a reliable temporal structure. We also found that males could localize the source of vibration but only if both the acoustic and vibratory components of the duet were played back. This unique multimodal duetting system may have evolved in response to higher levels of bat predation on searching bushcricket females than calling males, shifting part of the risk associated with partner localization onto the male. This is the first known example of bushcricket female tremulation in response to a long-range male acoustic signal and the first known example of a multimodal duet among animals. PMID:26254322

  17. Complex vibratory patterns in an elephant larynx.

    PubMed

    Herbst, Christian T; Svec, Jan G; Lohscheller, Jörg; Frey, Roland; Gumpenberger, Michaela; Stoeger, Angela S; Fitch, W Tecumseh

    2013-11-01

    Elephants' low-frequency vocalizations are produced by flow-induced self-sustaining oscillations of laryngeal tissue. To date, little is known in detail about the vibratory phenomena in the elephant larynx. Here, we provide a first descriptive report of the complex oscillatory features found in the excised larynx of a 25 year old female African elephant (Loxodonta africana), the largest animal sound generator ever studied experimentally. Sound production was documented with high-speed video, acoustic measurements, air flow and sound pressure level recordings. The anatomy of the larynx was studied with computed tomography (CT) and dissections. Elephant CT vocal anatomy data were further compared with the anatomy of an adult human male. We observed numerous unusual phenomena, not typically reported in human vocal fold vibrations. Phase delays along both the inferior-superior and anterior-posterior (A-P) dimension were commonly observed, as well as transverse travelling wave patterns along the A-P dimension, previously not documented in the literature. Acoustic energy was mainly created during the instant of glottal opening. The vestibular folds, when adducted, participated in tissue vibration, effectively increasing the generated sound pressure level by 12 dB. The complexity of the observed phenomena is partly attributed to the distinct laryngeal anatomy of the elephant larynx, which is not simply a large-scale version of its human counterpart. Travelling waves may be facilitated by low fundamental frequencies and increased vocal fold tension. A travelling wave model is proposed, to account for three types of phenomena: A-P travelling waves, 'conventional' standing wave patterns, and irregular vocal fold vibration. PMID:24133151

  18. Responses to Changes in Ca2+ Supply in Two Mediterranean Evergreens, Phillyrea latifolia and Pistacia lentiscus, During Salinity Stress and Subsequent Relief

    PubMed Central

    Tattini, Massimiliano; Traversi, Maria Laura

    2008-01-01

    Background and Aims Changes in root-zone Ca2+ concentration affect a plant's performance under high salinity, an issue poorly investigated for Mediterranean xerophytes, which may suffer from transient root-zone salinity stress in calcareous soils. It was hypothesized that high-Ca2+ supply may affect differentially the response to salinity stress of species differing in their strategy of Na+ allocation at organ level. Phillyrea latifolia and Pistacia lentiscus, which have been reported to greatly differ for Na+ uptake and transport rates to the leaves, were studied. Methods In plants exposed to 0 mm or 200 mm NaCl and supplied with 2·0 mm or 8·0 mm Ca2+, under 100 % solar irradiance, measurements were conducted of (a) gas exchange, PSII photochemistry and plant growth; (b) water and ionic relations; (c) the activity of superoxide dismutase and the lipid peroxidation; and (d) the concentration of individual polyphenols. Gas exchange and plant growth were also estimated during a period of relief from salinity stress. Key Results The performance of Pistacia lentiscus decreased to a significantly smaller degree than that of Phillyrea latifolia because of high salinity. Ameliorative effects of high-Ca2+ supply were more evident in Phillyrea latifolia than in Pistacia lentiscus. High-Ca2+ reduced steeply the Na+ transport to the leaves in salt-treated Phillyrea latifolia, and allowed a faster recovery of gas exchange and growth rates as compared with low-Ca2+ plants, during the period of relief from salinity. Salt-induced biochemical adjustments, mostly devoted to counter salt-induced oxidative damage, were greater in Phillyrea latifolia than in Pistacia lentiscus. Conclusions An increased Ca2+ : Na+ ratio may be of greater benefit for Phillyrea latifolia than for Pistacia lentiscus, as in the former, adaptive mechanisms to high root-zone salinity are primarily devoted to restrict the accumulation of potentially toxic ions in sensitive shoot organs. PMID:18701601

  19. Analysis of rabbit intervertebral disc physiology based on water metabolism. II. Changes in normal intervertebral discs under axial vibratory load

    SciTech Connect

    Hirano, N.; Tsuji, H.; Ohshima, H.; Kitano, S.; Itoh, T.; Sano, A.

    1988-11-01

    Metabolic changes induced by axial vibratory load to the spine were investigated based on water metabolism in normal intervertebral discs of rabbits with or without pentobarbital anesthesia. Tritiated water concentration in the intervertebral discs of unanesthetized rabbits was reduced remarkably by axial vibration for 30 minutes using the vibration machine developed for this study. Repeated vibratory load for 18 and 42 hours duration showed the recovery of /sup 3/H/sub 2/O concentration of the intervertebral disc without anesthesia. Computer simulation suggested a reduction of blood flow surrounding the intervertebral disc following the vibration stress. However, no reduction of the /sup 3/H/sub 2/O concentration in the intervertebral disc was noted under anesthesia. Emotional stress cannot be excluded as a factor in water metabolism in the intervertebral disc.

  20. On Landing Gear Stresses

    NASA Technical Reports Server (NTRS)

    Gentric, A.

    1956-01-01

    Information on landing gear stresses is presented on the following: vibratory phenomena, tangential forces applied to landing gear, fore and aft oscillations of landing gears, examples of fatigue failures, vibration calculations, and improvement of existing test equipment.

  1. Vibratory compaction tests on graphite powders for neutron shielding

    SciTech Connect

    Morgan, W.C.

    1982-05-01

    Mistures of three size ranges of graphite powders have been vibratory packed to densities as high as 1.40 gm/cm/sup 3/, which is 87.5 percent of the design density for the graphte segment of the FMIT test cell shield. Ultrasonic resonance vibration of the particles was determined to be an impractical method for achieving the required density. Possible options for fabricating the shield are: (1) revert to solid graphite, rather than vibratory packed powder, or (2) develop the mechanical vibratory compaction method, which would require (a) designing for the higher heat-load attendant with the reduced graphite density, or (b) increasing the thickness of the graphite segment by 15 percent or (c) seeking a new source of graphite powder with higher particle density.

  2. Modifications of Fabrication of Vibratory Microgyroscopes

    NASA Technical Reports Server (NTRS)

    Bae, Sam Y.; Yee, Karl Y.; Wiberg, Dean

    2005-01-01

    A micromachining process for the fabrication of vibratory microgyroscopes from silicon wafers, and aspects of the microgyroscope design that are inextricably linked with the fabrication process, have been modified in an effort to increase production yields from perspectives of both quantity and quality. Prior to the modifications, the effective production yield of working microgyroscopes was limited to one or less per wafer. The modifications are part of a continuing effort to improve the design and increase production yields to more than 30 working microgyroscopes per wafer. A discussion of pertinent aspects of the unmodified design and the unmodified fabrication process is prerequisite to a meaningful description of the modifications. The design of the microgyroscope package was not conducive to high yield and rapid testing of many microgyroscopes. One of the major impediments to high yield and testing was found to lie in vibration- isolation beams around the four edges of each microgyroscope, which beams were found to be unnecessary for achieving high resonance quality factors (Q values) characterizing the vibrations of petallike cantilevers. The fabrication process included an 8- m-deep plasma etch. The purpose of the etch was to create 8- m vertical gaps, below which were to be placed large gold evaporated electrodes and sensing pads to drive and sense resonant vibrations of the "petals." The process also included a step in which bridges between dies were cut to separate the dies. The etched areas must be kept clean and smooth (free of debris and spikes), because any object close to 8 m high in those areas would stop the vibrations. However, it was found that after the etch, there remained some spikes with heights that were, variously, almost as high or as high as the etch depth. It also was found that the cutting of bridges created silicon debris, some of which lodged in the 8- m gaps and some of which landed on top of the petals. The masses added to the

  3. Relief of Oxidative Stress Using Curcumin and Glutathione Functionalized ZnO Nanoparticles in HEK-293 Cell Line.

    PubMed

    Kumar, Amit; Zafaryab, Md; Umar, Ahmad; Rizvi, M M A; Fouad, H; Ansari, Z A; Ansari, S G

    2015-11-01

    To elucidate the effect of zinc oxide nanoparticles (ZnO-NPs) with different surface modifications in relieving the oxidative stress in cultured human embryonic kidney cells (HEK-293) following investigation was performed. Oxidative stress was artificially induced by hydrogen peroxide in HEK-293 cell culture and its management was studied. Alkyl amines modified ZnO-NPs with curcumin and reduced glutathione (GSH) functionalization was used in managing oxidative stress and had shown promising results. ZnO-NPs used in this study were synthesized via non-aqueous sol-gel method and FESEM characterisation showed them of spherical shape of about 20-50 nm size with amine, curcumin and GSH functionalization. UV-visible and FTIR spectroscopic characterizations confirmed functionalization of ZnO-NPs. Decrease in oxidative stress was found with the dose-dependent culture of HEK-293 cells with these functionalized ZnO-NPs. Cell viability and morphology, as observed using AFM and inverted microscope, was retained with the prescribed dosages of the functionalized nanoparticles while at higher dosages they caused cytotoxicity and death. Diethylamine (DEA) modified ZnO-NPs and their functionalization with GSH and curcumin were found more effective in managing oxidative stress in cells. Present study could help in designing economical and bio-compatible functionalized non-toxic nanoparticles designed for managing oxidative stress leading to possible therapeutical and medicinal uses. PMID:26554152

  4. 21 CFR 884.4270 - Vibratory cervical dilators.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... viable fetus is desired or anticipated. (b) Classification. Class III (premarket approval). (c) Date PMA or notice of completion of a PDP is required. A PMA or a notice of completion of a PDP is required to... commercial distribution before May 28, 1976. Any other vibratory cervical dilator shall have an approved...

  5. 21 CFR 884.4270 - Vibratory cervical dilators.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... viable fetus is desired or anticipated. (b) Classification. Class III (premarket approval). (c) Date PMA or notice of completion of a PDP is required. A PMA or a notice of completion of a PDP is required to... commercial distribution before May 28, 1976. Any other vibratory cervical dilator shall have an approved...

  6. 21 CFR 884.4270 - Vibratory cervical dilators.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Vibratory cervical dilators. 884.4270 Section 884.4270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... be filed with the Food and Drug Administration on or before December 26, 1996 for any...

  7. 21 CFR 884.4270 - Vibratory cervical dilators.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Vibratory cervical dilators. 884.4270 Section 884.4270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... be filed with the Food and Drug Administration on or before December 26, 1996 for any...

  8. 21 CFR 884.4270 - Vibratory cervical dilators.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Vibratory cervical dilators. 884.4270 Section 884.4270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... be filed with the Food and Drug Administration on or before December 26, 1996 for any...

  9. Alternative medicine - pain relief

    MedlinePlus

    Acupuncture - pain relief; Hypnosis - pain relief; Guided imagery - pain relief ... you repeat a positive statement over and over. Hypnosis may help relieve pain for: After surgery or labor Arthritis Cancer Fibromyalgia ...

  10. OMP Peptides Activate the DegS Stress-Sensor Protease by a Relief of Inhibition Mechanism

    SciTech Connect

    Sohn, Jungsan; Grant, Robert A.; Sauer, Robert T.; MIT

    2010-03-19

    In the E. coli periplasm, C-terminal peptides of misfolded outer-membrane porins (OMPs) bind to the PDZ domains of the trimeric DegS protease, triggering cleavage of a transmembrane regulator and transcriptional activation of stress genes. We show that an active-site DegS mutation partially bypasses the requirement for peptide activation and acts synergistically with mutations that disrupt contacts between the protease and PDZ domains. Biochemical results support an allosteric model, in which these mutations, active-site modification, and peptide/substrate binding act in concert to stabilize proteolytically active DegS. Cocrystal structures of DegS in complex with different OMP peptides reveal activation of the protease domain with varied conformations of the PDZ domain and without specific contacts from the bound OMP peptide. Taken together, these results indicate that the binding of OMP peptides activates proteolysis principally by relieving inhibitory contacts between the PDZ domain and the protease domain of DegS.

  11. Vibratory Urticaria Associated with a Missense Variant in ADGRE2.

    PubMed

    Boyden, Steven E; Desai, Avanti; Cruse, Glenn; Young, Michael L; Bolan, Hyejeong C; Scott, Linda M; Eisch, A Robin; Long, R Daniel; Lee, Chyi-Chia R; Satorius, Colleen L; Pakstis, Andrew J; Olivera, Ana; Mullikin, James C; Chouery, Eliane; Mégarbané, André; Medlej-Hashim, Myrna; Kidd, Kenneth K; Kastner, Daniel L; Metcalfe, Dean D; Komarow, Hirsh D

    2016-02-18

    Patients with autosomal dominant vibratory urticaria have localized hives and systemic manifestations in response to dermal vibration, with coincident degranulation of mast cells and increased histamine levels in serum. We identified a previously unknown missense substitution in ADGRE2 (also known as EMR2), which was predicted to result in the replacement of cysteine with tyrosine at amino acid position 492 (p.C492Y), as the only nonsynonymous variant cosegregating with vibratory urticaria in two large kindreds. The ADGRE2 receptor undergoes autocatalytic cleavage, producing an extracellular subunit that noncovalently binds a transmembrane subunit. We showed that the variant probably destabilizes an autoinhibitory subunit interaction, sensitizing mast cells to IgE-independent vibration-induced degranulation. (Funded by the National Institutes of Health.). PMID:26841242

  12. Characterization of the bell-shaped vibratory angular rate gyro.

    PubMed

    Liu, Ning; Su, Zhong; Li, Qing; Fu, MengYin; Liu, Hong; Fan, JunFang

    2013-01-01

    The bell-shaped vibratory angular rate gyro (abbreviated as BVG) is a novel shell vibratory gyroscope, which is inspired by the Chinese traditional bell. It sensitizes angular velocity through the standing wave precession effect. The bell-shaped resonator is a core component of the BVG and looks like the millimeter-grade Chinese traditional bell, such as QianLong Bell and Yongle Bell. It is made of Ni43CrTi, which is a constant modulus alloy. The exciting element, control element and detection element are uniformly distributed and attached to the resonator, respectively. This work presents the design, analysis and experimentation on the BVG. It is most important to analyze the vibratory character of the bell-shaped resonator. The strain equation, internal force and the resonator's equilibrium differential equation are derived in the orthogonal curvilinear coordinate system. When the input angular velocity is existent on the sensitive axis, an analysis of the vibratory character is performed using the theory of thin shells. On this basis, the mode shape function and the simplified second order normal vibration mode dynamical equation are obtained. The coriolis coupling relationship about the primary mode and secondary mode is established. The methods of the signal processing and control loop are presented. Analyzing the impact resistance property of the bell-shaped resonator, which is compared with other shell resonators using the Finite Element Method, demonstrates that BVG has the advantage of a better impact resistance property. A reasonable means of installation and a prototypal gyro are designed. The gyroscopic effect of the BVG is characterized through experiments. Experimental results show that the BVG has not only the advantages of low cost, low power, long work life, high sensitivity, and so on, but, also, of a simple structure and a better impact resistance property for low and medium angular velocity measurements. PMID:23966183

  13. Deburring die-castings by wet vibratory plant

    NASA Astrophysics Data System (ADS)

    Loeschbart, H. M.

    1980-02-01

    A wet vibratory procedure for the removal of burrs from die castings is described. In this process synthetic abrasive chips and detergent solutions are agitated with the work in such a way as to produce a spiral circulatory movement. Details of various forms of vibrator basin and shapes of abrasive are illustrated. The automation of deburring is illustrated through the application of vibrators of spiral design in combination with transport and drying devices.

  14. Deburring die-castings by wet vibratory plant

    NASA Technical Reports Server (NTRS)

    Loeschbart, H. M.

    1980-01-01

    A wet vibratory procedure for the removal of burrs from die castings is described. In this process synthetic abrasive chips and detergent solutions are agitated with the work in such a way as to produce a spiral circulatory movement. Details of various forms of vibrator basin and shapes of abrasive are illustrated. The automation of deburring is illustrated through the application of vibrators of spiral design in combination with transport and drying devices.

  15. Characterization of the Bell-Shaped Vibratory Angular Rate Gyro

    PubMed Central

    Liu, Ning; Su, Zhong; Li, Qing; Fu, MengYin; Liu, Hong; Fan, JunFang

    2013-01-01

    The bell-shaped vibratory angular rate gyro (abbreviated as BVG) is a novel shell vibratory gyroscope, which is inspired by the Chinese traditional bell. It sensitizes angular velocity through the standing wave precession effect. The bell-shaped resonator is a core component of the BVG and looks like the millimeter-grade Chinese traditional bell, such as QianLong Bell and Yongle Bell. It is made of Ni43CrTi, which is a constant modulus alloy. The exciting element, control element and detection element are uniformly distributed and attached to the resonator, respectively. This work presents the design, analysis and experimentation on the BVG. It is most important to analyze the vibratory character of the bell-shaped resonator. The strain equation, internal force and the resonator's equilibrium differential equation are derived in the orthogonal curvilinear coordinate system. When the input angular velocity is existent on the sensitive axis, an analysis of the vibratory character is performed using the theory of thin shells. On this basis, the mode shape function and the simplified second order normal vibration mode dynamical equation are obtained. The coriolis coupling relationship about the primary mode and secondary mode is established. The methods of the signal processing and control loop are presented. Analyzing the impact resistance property of the bell-shaped resonator, which is compared with other shell resonators using the Finite Element Method, demonstrates that BVG has the advantage of a better impact resistance property. A reasonable means of installation and a prototypal gyro are designed. The gyroscopic effect of the BVG is characterized through experiments. Experimental results show that the BVG has not only the advantages of low cost, low power, long work life, high sensitivity, and so on, but, also, of a simple structure and a better impact resistance property for low and medium angular velocity measurements. PMID:23966183

  16. Innovative decontamination technology by abrasion in vibratory vessels

    SciTech Connect

    Fabbri, Silvio; Ilarri, Sergio

    2007-07-01

    Available in abstract form only. Full text of publication follows: The possibility of using conventional vibratory vessel technology as a decontamination technique is the motivation for the development of this project. The objective is to explore the feasibility of applying the vibratory vessel technology for decontamination of radioactively-contaminated materials such as pipes and metal structures. The research and development of this technology was granted by the U.S. Department of Energy (DOE). Abrasion processes in vibratory vessels are widely used in the manufacture of metals, ceramics, and plastics. Samples to be treated, solid abrasive media and liquid media are set up into a vessel. Erosion results from the repeated impact of the abrasive particles on the surface of the body being treated. A liquid media, generally detergents or surfactants aid the abrasive action. The amount of material removed increases with the time of treatment. The design and construction of the machine were provided by Vibro, Argentina private company. Tests with radioactively-contaminated aluminum tubes and a stainless steel bar, were performed at laboratory level. Tests showed that it is possible to clean both the external and the internal surface of contaminated tubes. Results show a decontamination factor around 10 after the first 30 minutes of the cleaning time. (authors)

  17. LOX, GOX and Pressure Relief

    NASA Technical Reports Server (NTRS)

    McLeod, Ken; Stoltzfus, Joel

    2006-01-01

    Oxygen relief systems present a serious fire hazard risk with often severe consequences. This presentation offers a risk management solution strategy which encourages minimizing ignition hazards, maximizing best materials, and utilizing good practices. Additionally, the relief system should be designed for cleanability and ballistic flow. The use of the right metals, softgoods, and lubricants, along with the best assembly techniques, is stressed. Materials should also be tested if data is not available and a full hazard analysis should be conducted in an effort to minimize risk and harm.

  18. Stress Relief for the Caregiver

    MedlinePlus

    ... you can take a break from your caregiving responsibilities to enjoy time alone or with friends. Visit ... respite, by allowing another individual to assume caregiving responsibilities for a limited period of time. It gives ...

  19. Chaotic behavior on in-phase vibratory conveyors

    SciTech Connect

    Raski, J.Z.

    1998-07-01

    One of the basic building blocks of IBM's computer technology is the thin-film interstitial metallized ceramic (IMC) substrate. The packaging of these substrates employs small input/output (IO) pins to provide both mechanical and electrical connection to the printed circuit board. In the automated manufacturing of the substrate, the input and output pins are individually conveyed by in-line vibratory conveyors. However, a nonperiodic motion of these pins is observed at certain angles of conveyor table tilt that cannot be explained by classical models of friction. This paper models the motion of a single I/O pin on an in-phase, linearly oscillating conveyor using the classical model of friction and compares that result with experimental observations. It is shown here, analytically and experimentally, that when the vibratory conveyor table amplitude and the coefficient of friction between the pin and the table are sufficiently large, the pin is conveyed forward with some velocity. If the conveyor table's angle of tilt is sufficiently large and the coefficient of friction is sufficiently low, the pin may slip backwards just as fast as the conveyor table drives it forward, resulting in a net pin velocity of zero. Surrounding the condition at which the net velocity of the pin is zero is a chaotic basin of attraction in which the pin motion is non-periodic. This basin of attraction was experimentally determined to be bracketed within a range of values of the coefficient of friction. The implications of these theoretical and experimental results are discussed in terms of the practical application of in-phase vibratory conveyors in manufacturing.

  20. Generalized Vibratory Deficits in Osteoarthritis of the Hip

    PubMed Central

    SHAKOOR, NAJIA; LEE, KRISTEN J.; FOGG, LOUIS F.; BLOCK, JOEL A.

    2013-01-01

    Objective Lower extremity sensory deficits, including reduced proprioception, joint kinesthesia, and, recently, vibratory sense, have been described in subjects with osteoarthritis (OA) of the knee. However, comparable deficits in OA of the hip have not previously been evaluated. Vibratory perception threshold (VPT) is a reliable measure used to assess sensory deficits and is amenable to testing multiple body sites. This study examined VPT at the upper and lower extremities of subjects with hip OA compared with subjects without hip OA. Methods Fourteen subjects with symptomatic and radiographic hip OA were compared with 13 age-matched controls without hip OA. VPT was assessed using a biothesiometer. Five sites in the lower extremity and 1 site in the upper extremity (radial head) were evaluated and compared between OA and control subjects. Results VPT was significantly reduced at all 6 testing sites of the OA subjects compared with controls (P < 0.05 for all sites). VPT scores (mean ± SEM volts) for OA subjects and controls were as follows: first metatarsophalangeal joint (13.5 ± 1.4 versus 7.4 ± 0.7), medial malleolus (18.1 ± 2.6 versus 11.2 ± 1.7), lateral malleolus (20.9 ± 2.4 versus 10.6 ± 1.5), medial femoral condyle (22.8 ± 2.9 versus 12.6 ± 1.3), lateral femoral condyle (26.7 ± 2.6 versus 16.2 ± 1.9), and radial head (10.2 ± 0.8 versus 7.5 ± 0.6). Conclusion To our knowledge, this is the first study to evaluate sensory deficits in hip OA and to demonstrate that there is vibratory sense loss at both the upper and lower extremities in these subjects compared with controls. The noted generalized deficits may have significant implications in the neuromechanical pathophysiology of OA. PMID:18759259

  1. Investigation of residual stresses in a multipass weld in 1 in. stainless steel plate

    SciTech Connect

    Spooner, S.; Fernandez Baca, J.A.; David, S.A.; Hubbard, C.R.; Holden, T.M.; Root, J.H.

    1994-06-01

    Residual stresses and strains were measured in two welded 25-mm thick plates of type 304 stainless steel by the neutron diffraction. The filler metal was type 308 stainless steel and the weld zone had a two phase microstructure in which the austenitic phase lattice parameter differs from the base metal. In these circumstances stain-free samples were taken from the weld zone area for analysis of the lattice parameters and ferrite content using neutron powder diffraction. Corrections for lattice parameter variation were applied permitting the calculation of residual strains and stresses in weld zone, heat affected zone (HAZ) and base metal. One of the two welds was examined without stress relief and the other was given a stress relief treatment consisting of vibration at a frequency below the resonant condition dudng welding. In both plates the largest residual stress component (longitudinal) is found in the fusion zone near the boundary between the weld zone and the heat affected zone. This longitudinal component is 400 {plus_minus} 50 MPa in tension. The normal stresses are generally close to zero although large fluctuations are found in the weld zone. The transverse stresses are as high as 200 MPa in the weld zone and decrease to 50 MPa {plus_minus} 40 MPa. The lattice parameter variation was equivalent to 5 {times} l0{minus}4 compressive strain and the ferrite content approached 9 percent at the center of the weld zone. Variations in residual stresses with thickness through the base metal plate were small. The treated plate and untreated plate showed nearly identical patterns of stress distribution. Differences in the measured stresses between vibratory-stress-relief treated and untreated plates fall within error bars of the stress determination in these particular 25 mm thick 300-type stainless steel plates.

  2. Modification of piezoelectric vibratory gyroscope resonator parameters by feedback control.

    PubMed

    Loveday, P W; Rogers, C A

    1998-01-01

    A method for analyzing the effect of feedback control on the dynamics of piezoelectric resonators used in vibratory gyroscopes has been developed. This method can be used to determine the feasibility of replacing the traditional mechanical balancing operations, used to adjust the resonant frequency, by displacement feedback and for determining the velocity feedback required to produce a particular bandwidth. Experiments were performed on a cylindrical resonator with discrete piezoelectric actuation and sensing elements to demonstrate the principles. Good agreement between analysis and experiment was obtained, and it was shown that this type of resonator could be balanced by displacement feedback. The analysis method presented also is applicable to micromachined piezoelectric gyroscopes. PMID:18244281

  3. Classification of vibratory patterns of the upper airway during sleep.

    PubMed

    Alshaer, Hisham; Rudzicz, Frank; Falk, Tiago H; Tseng, Wen-Hou; Bradley, T Douglas

    2013-01-01

    Upper airway (UA) narrowing and collapse during sleep results in obstructive sleep apnea (OSA). We hypothesize that vibratory patterns of snoring can distinguish simple snorers from those with OSA. Samples of breath sounds were collected from 7 snorers without OSA and 5 with OSA. Snoring pitch (F0) contours were found using the robust algorithm for pitch tracking (RAPT). The OSA snoring contours showed fluctuating patterns as compared to the smoother patterns of simple snorers. This suggests that snoring reveals the underlying instabilities of UA tissue in OSA. Conditional random fields, a statistical sequence classifier, gave 75% accuracy in distinguishing the 2 groups. PMID:24110129

  4. A subharmonic vibratory pattern in normal vocal folds.

    PubMed

    Svec, J G; Schutte, H K; Miller, D G

    1996-02-01

    This study observes in detail an F0/2 (sounding an octave below an original tone) subharmonic vibratory pattern produced in a normal larynx. Simultaneous electroglottographic and photoglottographic measurements reveal two different open phases within a subharmonic cycle- the first shorter with a simple shape, the second longer with a shape containing a "ripple." Such parameters as the large open quotient (ca. 0.8) and the high airflow values (ca. 1000 cm3/s) distinguish this phonation from the vocal fry (pulse) register. Using an electronic divider to track the subharmonic frequency, a method has been developed to observe the subharmonic vibration of the vocal folds stroboscopically. The stroboscopic visualization reveals an unusual mucosal movement during the "ripple," characterized by an opening movement of the upper margins, which interrupts the closing movement of the vocal folds. An explanation is offered that this vibratory pattern arises as a consequence of detuning of the usually identical frequencies of the dominant modes of the vocal folds, with 3:2 entrainment replacing the normal 1:1 pattern. PMID:8820705

  5. The underwater sound field from vibratory pile driving.

    PubMed

    Dahl, Peter H; Dall'Osto, David R; Farrell, Dara M

    2015-06-01

    Underwater noise from vibratory pile driving was observed using a vertical line array placed at range 16 m from the pile source (water depth 7.5 m), and using single hydrophones at range 417 m on one transect, and range 207 and 436 m on another transect running approximately parallel to a sloping shoreline. The dominant spectral features of the underwater noise are related to the frequency of the vibratory pile driving hammer (typically 15-35 Hz), producing spectral lines at intervals of this frequency. The mean-square pressure versus depth is subsequently studied in third-octave bands. Depth and frequency variations of this quantity observed at the vertical line array are well modeled by a field consisting of an incoherent sum of sources distributed over the water column. Adiabatic mode theory is used to propagate this field to greater ranges and model the observations made along the two depth-varying transects. The effect of shear in the seabed, although small, is also included. Bathymetric refraction on the transect parallel to the shoreline reduced mean-square pressure levels at the 436-m measurement site. PMID:26093441

  6. Vibratory compaction method for preparing lunar regolith drilling simulant

    NASA Astrophysics Data System (ADS)

    Chen, Chongbin; Quan, Qiquan; Deng, Zongquan; Jiang, Shengyuan

    2016-07-01

    Drilling and coring is an effective way to acquire lunar regolith samples along the depth direction. To facilitate the modeling and simulation of lunar drilling, ground verification experiments for drilling and coring should be performed using lunar regolith simulant. The simulant should mimic actual lunar regolith, and the distribution of its mechanical properties should vary along the longitudinal direction. Furthermore, an appropriate preparation method is required to ensure that the simulant has consistent mechanical properties so that the experimental results can be repeatable. Vibratory compaction actively changes the relative density of a raw material, making it suitable for building a multilayered drilling simulant. It is necessary to determine the relation between the preparation parameters and the expected mechanical properties of the drilling simulant. A vibratory compaction model based on the ideal elastoplastic theory is built to represent the dynamical properties of the simulant during compaction. Preparation experiments indicated that the preparation method can be used to obtain drilling simulant with the desired mechanical property distribution along the depth direction.

  7. Vibratory strain field measurement by transverse digital holography.

    PubMed

    Stetson, Karl A

    2015-09-20

    A method is presented for measuring vibratory strain fields using phase-stepped, image-plane digital holography. An object surface is observed along its normal vector while illuminated at equal and opposite angles by two mutually coherent laser beams. One beam is phase stepped by quarter-wavelength increments between TV frames, and the resulting images are processed to yield holographic images. Object vibrations result in zero-order Bessel function fringes in the display. The second beam is modulated at the same frequency of the object vibration and is used to shift the fringes in a manner analogous to phase step interferometry. The resulting images are processed to yield a wrapped phase map, which is unwrapped and corrected for the error associated with using zero-order Bessel functions in place of cosine functions. The unwrapped images are processed to obtain the average slopes for image segments, and these slopes are multiplied by a scale factor to convert them to strain. The analysis program used here divides the field of view into five horizontal by four vertical segments, which provide a map of the vibratory strain field. PMID:26406526

  8. COPD - quick-relief drugs

    MedlinePlus

    COPD - quick-relief drugs; Chronic obstructive pulmonary disease - control drugs; Chronic obstructive airways disease - quick-relief drugs; Chronic obstructive lung disease - quick-relief drugs; Chronic bronchitis - quick-relief ...

  9. Parametric identification of a vibratory system with a clearance

    NASA Technical Reports Server (NTRS)

    Alexander, R. M.; Noah, S. T.; Franck, C. G.

    1993-01-01

    An analytical and experimental investigation of a vibratory system with a clearance was conducted. A finite element model and an equivalent single-degree-of-freedom closed-form solution were used to determine the dynamic parameters and response of an experimental structure interacting with a gap. The closed-form solution is obtained by taking advantage of the piecewise linearity of the system. Results from these solution methods are in agreement with experimental data. The results also suggest that the closed-form solution approximates the response of the experimental structure with accuracy greater than that of the finite element model. The closed-form solution was also used to determine the gap size of the structure. The parameter identification procedure utilized in this study appears to be simple to use and can be readily extended to other types of piecewise-linear multi-degree-of-freedom systems.

  10. [Relation between voice quality and pathological vibratory patterns using high-speed digital imaging].

    PubMed

    Miyaji, M; Iwamoto, Y; Oda, M; Niimi, S

    1999-03-01

    We analysed the vocal fold vibrations of 22 pathological larynges using a computer-assisted high-speed digital imaging technique. The parameters observed included symmetry, regularity, phase difference, glottal closure, amplitude, mucosal wave and periodicity difference. Voice quality was evaluated by a GRBAS system, and we examined the relation between vocal fold vibration patterns and voice quality. The intraexaminer correlation coefficient was high for the G, R and B scales. Vibratory patterns were classified according to the location of the lesion, severity of the disease, expiratory pressure and laryngeal modulation. Although there were no matches between a vocal fold vibratory pattern for one psychoacoustic impression of hoarseness, the characteristic vibratory patterns of these cases of R > or = 2.5 or diplophonia exhibited irregular glottal closure and periodicity differences. The characteristic vibratory pattern of vocal fry is a double or triple opening/closing phase, followed by a long closed phase. PMID:10226472

  11. Amitriptyline and bromazepam in the treatment of vibratory angioedema: which role for neuroinflammation?

    PubMed

    Guarneri, Fabrizio; Guarneri, Claudio; Marini, Herbert Ryan

    2014-01-01

    Vibratory angioedema is a rare form of physical urticaria, hereditary or acquired, which occurs at body sites exposed to vibrations. Pathogenic mechanisms of disease are not completely clear and, consequently, current pharmacological treatment is sometimes unsatisfactory. We report the case of a horn player affected by acquired vibratory angioedema, relapsing after prolonged use of the instrument and resistant to systemic antihistamines and corticosteroids, which successfully responded to therapy with low doses of amitriptyline and bromazepam. A neuroinflammatory mechanism can be likely implicated in the pathogenesis of vibratory angioedema, in line with many different cutaneous/mucosal diseases involving a complex interplay of homeostatic/allostatic systems. Furthermore, in mucosal diseases, such as vibratory angioedema, physical/psychological stressors have a relevant role. In such cases, because of the complex interplay between nervous and immune system, the pharmacological activity of benzodiazepines and typical antidepressants may downregulate neuroinflammation. PMID:25052839

  12. Jean-Martin Charcot and his vibratory chair for Parkinson disease.

    PubMed

    Goetz, Christopher G

    2009-08-11

    Vibration therapy is currently used in diverse medical specialties ranging from orthopedics to urology to sports medicine. The celebrated 19th-century neurologist, J.-M. Charcot, used vibratory therapy to treat Parkinson disease (PD). This study analyzed printed writings by Charcot and other writers on vibratory therapy and accessed unpublished notes from the Salpêtrière Hospital, Paris. Charcot lectured on several occasions on vibratory therapy and its neurologic applications. He developed a vibration chair for patients with PD after he observed that patients were more comfortable and slept better after a train or carriage ride. He replicated this experience by having patients undergo daily 30-minute sessions in the automated vibratory chair (fauteuil trépidant). His junior colleague, Gilles de la Tourette, extended these observations and developed a helmet that vibrated the head on the premise that the brain responded directly to the pulsations. Although after Charcot's death vibratory therapy was not widely pursued, vibratory appliances are reemerging in 21st century medicine and can be retested using adaptations of Charcot's neurologic protocols. PMID:19667323

  13. Characterization of relief printing

    NASA Astrophysics Data System (ADS)

    Liu, Xing; Chen, Lin; Ortiz-Segovia, Maria-Valezzka; Ferwerda, James; Allebach, Jan

    2014-03-01

    Relief printing technology developed by Océ allows the superposition of several layers of colorant on different types of media which creates a variation of the surface height defined by the input to the printer. Evaluating the reproduction accuracy of distinct surface characteristics is of great importance to the application of the relief printing system. Therefore, it is necessary to develop quality metrics to evaluate the relief process. In this paper, we focus on the third dimension of relief printing, i.e. height information. To achieve this goal, we define metrics and develop models that aim to evaluate relief prints in two aspects: overall fidelity and surface finish. To characterize the overall fidelity, three metrics are calculated: Modulation Transfer Function (MTF), difference and root-mean-squared error (RMSE) between the input height map and scanned height map, and print surface angle accuracy. For the surface finish property, we measure the surface roughness, generate surface normal maps and develop a light reflection model that serves as a simulation of the differences between ideal prints and real prints that may be perceived by human observers. Three sets of test targets are designed and printed by the Océ relief printer prototypes for the calculation of the above metrics: (i) twisted target, (ii) sinusoidal wave target, and (iii) ramp target. The results provide quantitative evaluations of the printing quality in the third dimension, and demonstrate that the height of relief prints is reproduced accurately with respect to the input design. The factors that affect the printing quality include: printing direction, frequency and amplitude of the input signal, shape of relief prints. Besides the above factors, there are two additional aspects that influence the viewing experience of relief prints: lighting condition and viewing angle.

  14. Relationships between CSID and vocal fold vibratory function

    NASA Astrophysics Data System (ADS)

    Cooke, Melissa L.

    High correlations have been reported between the acoustic-based Cepstral/Spectral Index of Dysphonia (CSID) and perceptual judgments of dysphonia. This study explores whether CSID provides additional insight and explains more of the variance in HSV-based properties of vocal fold vibratory function than has been reported for other acoustic measures. Using the Analysis of Dysphonia in Speech and Voice (ADSV) program, CSID and its component variables were correlated with HSV-based measures of glottal cycle aperiodicity and glottal area for 20 subjects who underwent phonomicrosurgery. Results indicate CSID is only marginally correlated with glottal cycle aperiodicity in pre- and post-surgical conditions and does not correlate as highly as the cepstral peak prominence alone. Additionally, results reveal higher correlations when examining within-subject change from pre-surgical to post-surgical assessments rather than correlating measures across subjects. Future directions are discussed that aim at improving our understanding of the relationships between acoustic parameters and underlying phonatory function.

  15. Error Model and Compensation of Bell-Shaped Vibratory Gyro

    PubMed Central

    Su, Zhong; Liu, Ning; Li, Qing

    2015-01-01

    A bell-shaped vibratory angular velocity gyro (BVG), inspired by the Chinese traditional bell, is a type of axisymmetric shell resonator gyroscope. This paper focuses on development of an error model and compensation of the BVG. A dynamic equation is firstly established, based on a study of the BVG working mechanism. This equation is then used to evaluate the relationship between the angular rate output signal and bell-shaped resonator character, analyze the influence of the main error sources and set up an error model for the BVG. The error sources are classified from the error propagation characteristics, and the compensation method is presented based on the error model. Finally, using the error model and compensation method, the BVG is calibrated experimentally including rough compensation, temperature and bias compensation, scale factor compensation and noise filter. The experimentally obtained bias instability is from 20.5°/h to 4.7°/h, the random walk is from 2.8°/h1/2 to 0.7°/h1/2 and the nonlinearity is from 0.2% to 0.03%. Based on the error compensation, it is shown that there is a good linear relationship between the sensing signal and the angular velocity, suggesting that the BVG is a good candidate for the field of low and medium rotational speed measurement. PMID:26393593

  16. Error Model and Compensation of Bell-Shaped Vibratory Gyro.

    PubMed

    Su, Zhong; Liu, Ning; Li, Qing

    2015-01-01

    A bell-shaped vibratory angular velocity gyro (BVG), inspired by the Chinese traditional bell, is a type of axisymmetric shell resonator gyroscope. This paper focuses on development of an error model and compensation of the BVG. A dynamic equation is firstly established, based on a study of the BVG working mechanism. This equation is then used to evaluate the relationship between the angular rate output signal and bell-shaped resonator character, analyze the influence of the main error sources and set up an error model for the BVG. The error sources are classified from the error propagation characteristics, and the compensation method is presented based on the error model. Finally, using the error model and compensation method, the BVG is calibrated experimentally including rough compensation, temperature and bias compensation, scale factor compensation and noise filter. The experimentally obtained bias instability is from 20.5°/h to 4.7°/h, the random walk is from 2.8°/h(1/2) to 0.7°/h(1/2) and the nonlinearity is from 0.2% to 0.03%. Based on the error compensation, it is shown that there is a good linear relationship between the sensing signal and the angular velocity, suggesting that the BVG is a good candidate for the field of low and medium rotational speed measurement. PMID:26393593

  17. Asthma Medicines: Quick Relief

    MedlinePlus

    ... Advisory Board Sponsors Sponsorship Opporunities Spread the Word Shop AAP Find a Pediatrician Health Issues Conditions Abdominal ... Listen Español Text Size Email Print Share Asthma Medicines: Quick Relief Page Content Article Body Short-Acting ...

  18. Speeding earthquake disaster relief

    USGS Publications Warehouse

    Mortensen, Carl; Donlin, Carolyn; Page, Robert A.; Ward, Peter

    1995-01-01

    In coping with recent multibillion-dollar earthquake disasters, scientists and emergency managers have found new ways to speed and improve relief efforts. This progress is founded on the rapid availability of earthquake information from seismograph networks.

  19. Stress-relaxation and tension relief system for immediate primary closure of large and huge soft tissue defects: an old-new concept: new concept for direct closure of large defects.

    PubMed

    Topaz, Moris; Carmel, Narin Nard; Topaz, Guy; Li, Mingsen; Li, Yong Zhong

    2014-12-01

    Stress-relaxation is a well-established mechanism for laboratory skin stretching, with limited clinical application in conventional suturing techniques due to the inherent, concomitant induction of ischemia, necrosis and subsequent suture failure. Skin defects that cannot be primarily closed are a common difficulty during reconstructive surgery. The TopClosure tension-relief system (TRS) is a novel device for wound closure closure, providing secured attachment to the skin through a wide area of attachment, in an adjustable manner, enabling primary closure of medium to large skin defects. The aim of this study was to evaluate the efficiency of the TopClosure TRS as a substitute for skin grafting and flaps for primary closure of large soft tissue defects by stress-relaxation. We present three demonstrative cases requiring resection of large to huge tumors customarily requiring closure by skin graft or flaps. TRS was applied during surgery serving as a tension-relief platform for tension sutures, to enable primary skin-defect closure by cycling of stress-relaxation, and following surgery as skin-secure system until complete wound closure. All skin defects ranging from 7 to 26 cm in width were manipulated by the TRS through stress-relaxation, without undermining of skin, enabling primary skin closure and eliminating the need for skin grafts and flaps. Immediate wound closure ranged 26 to 135 min. TRS was applied for 3 to 4 weeks. Complications were minimal and donor site morbidity was eliminated. Surgical time, hospital stay and costs were reduced and wound aesthetics were improved. In this case series we present a novel technology that enables the utilization of the viscoelastic properties of the skin to an extreme level, extending the limits of primary wound closure by the stress-relaxation principle. This is achieved via a simple device application that may aid immediate primary wound closure and downgrade the complexity of surgical procedures for a wide range

  20. Pressure Relief Devices

    NASA Astrophysics Data System (ADS)

    Manha, William D.

    2010-09-01

    Pressure relief devices are used in pressure systems and on pressure vessels to prevent catastrophic rupture or explosion from excessive pressure. Pressure systems and pressure vessels have manufacturers maximum rated operating pressures or maximum design pressures(MDP) for which there are relatively high safety factors and minimum risk of rupture or explosion. Pressure systems and pressure vessels that have a potential to exceed the MDP by being connected to another higher pressure source, a compressor, or heat to water(boiler) are required to have over-pressure protecting devices. Such devices can be relief valves and/or burst discs to safely relieve potentially excessive pressure and prevent unacceptable ruptures and explosions which result in fail-safe pressure systems and pressure vessels. Common aerospace relief valve and burst disc requirements and standards will be presented. This will include the NASA PSRP Interpretation Letter TA-88-074 Fault Tolerance of Systems Using Specially Certified Burst Disks that dictates burst disc requirements for payloads on Shuttle. Two recent undesirable manned space payloads pressure relief devices and practices will be discussed, as well as why these practices should not be continued. One example for discussion is the use of three burst discs that have been placed in series to comply with safety requirements of three controls to prevent a catastrophic hazard of the over-pressurization and rupture of pressure system and/or vessels. The cavities between the burst discs are evacuated and are the reference pressures for activating the two upstream burst discs. If the upstream burst disc leaks into the reference cavity, the reference pressure increases and it can increase the burst disc activating pressure and potentially result in the burst disc assembly being ineffective for over pressure protection. The three burst discs-in-series assembly was found acceptable because the burst discs are designed for minimum risk(DFMR) of

  1. Interference of Overlapping Insect Vibratory Communication Signals: An Eushistus heros Model

    PubMed Central

    Čokl, Andrej; Laumann, Raul Alberto; Žunič Kosi, Alenka; Blassioli-Moraes, Maria Carolina; Virant-Doberlet, Meta; Borges, Miguel

    2015-01-01

    Plants limit the range of insect substrate-borne vibratory communication by their architecture and mechanical properties that change transmitted signal time, amplitude and frequency characteristics. Stinkbugs gain higher signal-to-noise ratio and increase communication distance by emitting narrowband low frequency vibratory signals that are tuned with transmission properties of plants. The objective of the present study was to investigate hitherto overlooked consequences of duetting with mutually overlapped narrowband vibratory signals. The overlapped vibrations of the model stinkbug species Eushistus heros, produced naturally or induced artificially on different plants, have been analysed. They represent female and male strategies to preserve information within a complex masked signal. The brown stinkbugs E. heros communicate with species and gender specific vibratory signals that constitute characteristic duets in the calling, courtship and rivalry phases of mating behaviour. The calling female pulse overlaps the male vibratory response when the latency of the latter is shorter than the duration of the female triggering signal or when the male response does not inhibit the following female pulse. Overlapping of signals induces interference that changes their amplitude pattern to a sequence of regularly repeated pulses in which their duration and the difference between frequencies of overlapped vibrations are related inversely. Interference does not occur in overlapped narrow band female calling pulses and broadband male courtship pulse trains. In a duet with overlapped signals females and males change time parameters and increase the frequency difference between signals by changing the frequency level and frequency modulation pattern of their calls. PMID:26098637

  2. Interference of Overlapping Insect Vibratory Communication Signals: An Eushistus heros Model.

    PubMed

    Čokl, Andrej; Laumann, Raul Alberto; Žunič Kosi, Alenka; Blassioli-Moraes, Maria Carolina; Virant-Doberlet, Meta; Borges, Miguel

    2015-01-01

    Plants limit the range of insect substrate-borne vibratory communication by their architecture and mechanical properties that change transmitted signal time, amplitude and frequency characteristics. Stinkbugs gain higher signal-to-noise ratio and increase communication distance by emitting narrowband low frequency vibratory signals that are tuned with transmission properties of plants. The objective of the present study was to investigate hitherto overlooked consequences of duetting with mutually overlapped narrowband vibratory signals. The overlapped vibrations of the model stinkbug species Eushistus heros, produced naturally or induced artificially on different plants, have been analysed. They represent female and male strategies to preserve information within a complex masked signal. The brown stinkbugs E. heros communicate with species and gender specific vibratory signals that constitute characteristic duets in the calling, courtship and rivalry phases of mating behaviour. The calling female pulse overlaps the male vibratory response when the latency of the latter is shorter than the duration of the female triggering signal or when the male response does not inhibit the following female pulse. Overlapping of signals induces interference that changes their amplitude pattern to a sequence of regularly repeated pulses in which their duration and the difference between frequencies of overlapped vibrations are related inversely. Interference does not occur in overlapped narrow band female calling pulses and broadband male courtship pulse trains. In a duet with overlapped signals females and males change time parameters and increase the frequency difference between signals by changing the frequency level and frequency modulation pattern of their calls. PMID:26098637

  3. Relief memory consolidation requires protein synthesis within the nucleus accumbens.

    PubMed

    Bruning, Johann E A; Breitfeld, Tino; Kahl, Evelyn; Bergado-Acosta, Jorge R; Fendt, Markus

    2016-06-01

    Relief learning refers to the association of a stimulus with the relief from an aversive event. The thus-learned relief stimulus then can induce, e.g., an attenuation of the startle response or approach behavior, indicating positive valence. Previous studies revealed that the nucleus accumbens is essential for the acquisition and retrieval of relief memory. Here, we ask whether the nucleus accumbens is also the brain site for consolidation of relief memory into a long-term form. In rats, we blocked local protein synthesis within the nucleus accumbens by local infusions of anisomycin at different time points during a relief conditioning experiment. Accumbal anisomycin injections immediately after the relief conditioning session, but not 4 h later, prevented the consolidation into long-term relief memory. The retention of already consolidated relief memory was not affected by anisomycin injections. This identifies a time window and site for relief memory consolidation. These findings should complement our understanding of the full range of effects of adverse experiences, including cases of their distortion in humans such as post-traumatic stress disorder and/or phobias. PMID:26792192

  4. Hydrogen gas relief valve

    DOEpatents

    Whittlesey, Curtis C.

    1985-01-01

    An improved battery stack design for an electrochemical system having at least one cell from which a gas is generated and an electrolyte in communication with the cell is described. The improved battery stack design features means for defining a substantially closed compartment for containing the battery cells and at least a portion of the electrolyte for the system, and means in association with the compartment means for selectively venting gas from the interior of the compartment means in response to the level of the electrolyte within the compartment means. The venting means includes a relief valve having a float member which is actuated in response to the level of the electrolyte within the compartment means. This float member is adapted to close the relief valve when the level of the electrolyte is above a predetermined level and open the relief valve when the level of electrolyte is below this predetermined level.

  5. The monitoring system for vibratory disturbance detection in microgravity environment aboard the international space station

    NASA Technical Reports Server (NTRS)

    Laster, Rachel M.

    2004-01-01

    Scientists in the Office of Life and Microgravity Sciences and Applications within the Microgravity Research Division oversee studies in important physical, chemical, and biological processes in microgravity environment. Research is conducted in microgravity environment because of the beneficial results that come about for experiments. When research is done in normal gravity, scientists are limited to results that are affected by the gravity of Earth. Microgravity provides an environment where solid, liquid, and gas can be observed in a natural state of free fall and where many different variables are eliminated. One challenge that NASA faces is that space flight opportunities need to be used effectively and efficiently in order to ensure that some of the most scientifically promising research is conducted. Different vibratory sources are continually active aboard the International Space Station (ISS). Some of the vibratory sources include crew exercise, experiment setup, machinery startup (life support fans, pumps, freezer/compressor, centrifuge), thruster firings, and some unknown events. The Space Acceleration Measurement System (SAMs), which acts as the hardware and carefully positioned aboard the ISS, along with the Microgravity Environment Monitoring System MEMS), which acts as the software and is located here at NASA Glenn, are used to detect these vibratory sources aboard the ISS and recognize them as disturbances. The various vibratory disturbances can sometimes be harmful to the scientists different research projects. Some vibratory disturbances are recognized by the MEMS's database and some are not. Mainly, the unknown events that occur aboard the International Space Station are the ones of major concern. To better aid in the research experiments, the unknown events are identified and verified as unknown events. Features, such as frequency, acceleration level, time and date of recognition of the new patterns are stored in an Excel database. My task is to

  6. External stimuli in the form of vibratory massage after heart or lung transplantation.

    PubMed

    Doering, T J; Fieguth, H G; Steuernagel, B; Brix, J; Konitzer, M; Schneider, B; Fischer, G C

    1999-01-01

    Manual vibratory massage is part of the preventive physiotherapeutic activities performed in intensive care units. The vibratory massage can be performed manually or as electrovibratory massage. The manual massage is a fast rhythmical vibration performed by the arm and shoulder muscles of the masseur and transferred to the patient's thorax by the hand. The hand of the masseur has to achieve a tremor with a frequency of 8 to 11 tremors/s. The aim of the pilot study was to examine the influence of manual vibratory massage on the pulmonary function of postoperative patients who were receiving mechanical ventilation, with special interest being focused on pulmonary ventilation and perfusion and cerebral blood flow velocity. Manual vibratory massage was performed postoperatively in the intensive care unit on eight patients: three patients had undergone heart transplantation, three had undergone lung transplantation, and two had undergone coronary artery bypass grafting (mean age, 53.6+/-8 yr). With the aid of continuous monitoring, we examined the changes of the respiration parameters and the cerebral blood flow velocity (measured by transcranial Doppler sonography). The vibratory massage was performed with a frequency of 8 to 10 vibrations/s for 15 min, 7.5 min on each side of the thorax, starting from the lower costal arch and progressing to the upper thoracic aperture. For 10 min before, during, and 10 min after the massage, the parameters of peripheral oxygen saturation, central venous pressure, mean arterial pressure, heart rate, lung resistance and compliance, tidal volume, respiration rate, and cerebral blood flow velocity were recorded at 2-min intervals. Moreover, before and after vibratory massage, arterial blood gases were determined. In four of the eight patients, it was possible to determine pulmonary arterial pressure, pulmonary capillary wedge pressure, as well as pulmonary vascular resistance. During the vibratory massage, we could prove a significant

  7. High Relief Block Printing.

    ERIC Educational Resources Information Center

    Foster, Michael

    1989-01-01

    Explains a method of block printing using styrofoam shapes to make high relief. Describes the creation of the block design as well as the actual printing process. Uses a range of paper types for printing so children can see the results of using different media. (LS)

  8. Vent Relief Valve Test

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Shown is the disassembly, examination, refurbishment and testing of the LH2 ( liquid hydrogen) and LOX (liquid oxygen) vent and relief valves for the S-IVB-211 engine stage in support of the Constellation/Ares project. This image is extracted from high definition video and is the highest resolution available.

  9. Research on the Signal Process of a Bell-Shaped Vibratory Angular Rate Gyro

    PubMed Central

    Su, Zhong; Liu, Ning; Li, Qing; Fu, Mengyin; Liu, Hong; Fan, Junfang

    2014-01-01

    A bell-shaped vibratory angular rate gyro, which is inspired by the Chinese traditional bell, is a kind of axisymmetric shell resonator gyroscope. Its sensitive element is a vibratory-like Chinese traditional bell, using a piezoelectric element on the wall of the vibrator to detect the standing wave's precession to solve the input angular rate. This work mainly studies the circuit system of a bell-shaped vibratory angular rate gyro. It discusses the process of circuit system design, analysis and experiment, in detail, providing the foundation to develop a bell-shaped vibratory angular rate gyro. Since the bell-shaped resonator's curved structure has the characteristics of large noise in the piezoelectric signal and large harmonics, this paper analyzes its working and signal detection method, then gives the whole plan of the circuit system, including the drive module, the detection module and the control loop. It also studies every part of the whole system, gives a detailed design and analysis process and proves part of the circuit system using digital simulation. At the end of the article, the test result of the circuit system shows that it can remove the disadvantages of the curved structure having large noise in the piezoelectric signal and large harmonics and is more effective at solving the input angular rate. PMID:24633451

  10. Automated Measurement of Vocal Fold Vibratory Asymmetry from High-Speed Videoendoscopy Recordings

    ERIC Educational Resources Information Center

    Mehta, Daryush D.; Deliyski, Dimitar D.; Quatieri, Thomas F.; Hillman, Robert E.

    2011-01-01

    Purpose: In prior work, a manually derived measure of vocal fold vibratory phase asymmetry correlated to varying degrees with visual judgments made from laryngeal high-speed videoendoscopy (HSV) recordings. This investigation extended this work by establishing an automated HSV-based framework to quantify 3 categories of vocal fold vibratory…

  11. Assessment of Penile Vibratory Stimulation as a Management Strategy in Men with Secondary Retarded Orgasm

    PubMed Central

    Nelson, Christian J.; Ahmed, Absaar; Valenzuela, Rolando; Parker, Marilyn; Mulhall, John P.

    2016-01-01

    OBJECTIVES To evaluate the effectiveness of penile vibratory stimulation for the management of retarded orgasm. Retarded orgasm, a condition characterized by difficulty achieving orgasm and ejaculation, is one of the most recalcitrant of the male sexual dysfunctions. Currently, no evidence-based treatments have been proven to ameliorate this condition. METHODS Men who had a complete inability to achieve an orgasm during sexual relations in the previous 3 months were instructed in the use of penile vibratory stimulation. The men’s responses were measured by self-report of orgasm function and using the orgasm and satisfaction domains of the International Index of Erectile Function. The responses were assessed at baseline (admission into the study) and at 3 and 6 months. RESULTS A total of 36 men met the inclusion criteria, and 72% reported the restoration of orgasm. These responders reported that orgasm during sexual relations occurred 62% of the time. A statistically and clinically significant increase occurred in the orgasm and satisfaction domains of the International Index of Erectile Function between the baseline visit and the 3-month follow-up visit. These gains were sustained at 6 months. CONCLUSIONS Penile vibratory stimulation is an effective treatment for retarded orgasm. Penile vibratory stimulation should be integrated into current cognitive-behavioral sex therapy techniques to achieve maximal effectiveness and satisfaction. PMID:17382163

  12. Short-term intensive glycemic control improves vibratory sensation in type 2 diabetes.

    PubMed

    Fujita, Yoshihito; Fukushima, Mitsuo; Suzuki, Haruhiko; Taniguchi, Ataru; Nakai, Yoshikatsu; Kuroe, Akira; Yasuda, Koichiro; Hosokawa, Masaya; Yamada, Yuichiro; Inagaki, Nobuya; Seino, Yutaka

    2008-04-01

    Strict long-term glycemic control has been reported to prevent or improve diabetic peripheral neuropathy, but the effects of short-term glycemic control have not been clarified in patients with type 2 diabetes. To investigate reversibility of impaired vibratory sensation by short-term glycemic control, we used the TM31 liminometer and C64 tuning fork methods to measure peripheral neuropathy. Thirty-one type 2 diabetes patients with poor glycemic control (HbA1c: 10.8+/-0.4%, mean+/-S.E.M., range from 7.9% to 16.2%) were administered strict glycemic control. Vibratory sensation before and after short-term glycemic control was evaluated, and the metabolic profile including plasma glucose, HbA1c, total cholesterol, HDL cholesterol, triglyceride, and free fatty acid (FFA) was measured. After 20.0+/-2.1 days of strict glycemic control, vibratory sensation improved significantly in both upper and lower extremities, assessed by TM31 liminometer and C64 tuning fork. Along with the improved glycemic control, lipid metabolism (total cholesterol, triglyceride and FFA) was significantly improved. Thus, short-term intensive glycemic control can improve vibratory sensation, metabolic changes in glucose and lipid metabolism being the factors responsible for improved of peripheral nerve function. PMID:18262304

  13. Deceptive vibratory communication: pupae of a beetle exploit the freeze response of larvae to protect themselves

    PubMed Central

    Kojima, Wataru; Ishikawa, Yukio; Takanashi, Takuma

    2012-01-01

    It is argued that animal signals may have evolved so as to manipulate the response of receivers in a way that increases the fitness of the signallers. In deceptive communication, receivers incur costs by responding to false signals. Recently, we reported that pupae of the soil-inhabiting Japanese rhinoceros beetle Trypoxylus dichotoma produce vibratory signals to deter burrowing larvae, thereby protecting themselves. In the present study, monitoring of vibrations associated with larval movement revealed that T. dichotoma larvae remained motionless for ca 10 min when pupal vibratory signals were played back transiently (freeze response). Furthermore, pupal signals of T. dichotoma elicited a freeze response in three other scarabaeid species, whose pupae do not produce vibratory signals. This indicates that the freeze response to certain types of vibration evolved before the divergence of these species and has been evolutionarily conserved, presumably because of the fitness advantage in avoiding predators. Pupae of T. dichotoma have probably exploited pre-existing anti-predator responses of conspecific larvae to protect themselves by emitting deceptive vibratory signals. PMID:22675138

  14. Characterizing Vibratory Kinematics in Children and Adults with High-Speed Digital Imaging

    ERIC Educational Resources Information Center

    Patel, Rita; Dubrovskiy, Denis; Döllinger, Michael

    2014-01-01

    Purpose: The aim of this study is to quantify and identify characteristic vibratory motion in typically developing prepubertal children and young adults using high-speed digital imaging. Method: The vibrations of the vocal folds were recorded from 27 children (ages 5-9 years) and 35 adults (ages 21-45 years), with high speed at 4,000 frames per…

  15. Numerical Simulation of Stress-Relief Effects of Protective Layer Extraction / Symulacja numeryczna skutków odprężenia warstwy zabezpieczającej w trakcie jej wybierania

    NASA Astrophysics Data System (ADS)

    Tian-Rang, Jia; Zi-Min, Zhang; Chun-An, Tang; Yong-Jun, Zhang

    2013-06-01

    Field test and laboratory analog model test on the stress-relief effects of protective layer extraction are time-consuming and laborious. In this paper, on the basis of full consideration of rock heterogeinity and in combination with gas geology at Pingdingshan Mine 5, a numerical model was estalished with the gas-solid coupling rock failure process analysis system RFPA-Gas to simulate the stress variation law, roof and floor deformation, fracture evolution law, displacement in the protected seam, change in gas permeability and gas migration law during protective layer extraction. The simulation results repoduced stress variations in coal and rock strata, roof and floor deformation and fracture evolution process during protective layer extraction. The movement of rock strata were characterized by upper three zones and lower two zones: caving zone, fracture zone and bending subsidence zone in the vertical direction in the overlying strata; floor deformation and failure zone and elasto-plastic deformation zone in the vertical direction in the underlying strata. It showed that stress relief occurred in the protected seam, which led to vertical and horizontal displacements, significant increase in gas permeability, gas desorption and migration. Hence, the outburst threat in the protected seam was eliminated. Meanwhile, with comprehensive analysis of variaition of stress state, deformation characteristics and fracture distribution in coal seam and with consideration of changes in gas leakage rate, gas pressure and permeability, according to gas leakage rate, the floor strata of the protecive layer were divided into four leakage zones. They corresponded to four zones with different stress states and fracture development: original leakage zone - slow reducing leakage zone - dramatic increasing leakage zone- steady increasing leakage zone. This classification provides a clear direction for gas control in the protective layer. The simulation results are in good agreement

  16. Vibratory hub load data reduction and analysis from the reverse velocity rotor wind tunnel test, phase 2B

    NASA Technical Reports Server (NTRS)

    Taylor, R. B.

    1976-01-01

    The vibratory hub loads data analysis from the reverse velocity rotor wind tunnel test is reported. Vibratory loads were obtained from the rotating hub balance and also by synthesis of generalized coordinates from the blade flap bending moments. Load trends were defined as a function of speed, rotor thrust and 2 per rev cyclic from each of the data methods. These trends were compared to determine the degree of agreement between each method and provide substantiation for the generalized coordinate approach.

  17. Vibratory response modeling and verification of a high precision optical positioning system.

    SciTech Connect

    Barraza, J.; Kuzay, T.; Royston, T. J.; Shu, D.

    1999-06-18

    A generic vibratory-response modeling program has been developed as a tool for designing high-precision optical positioning systems. Based on multibody dynamics theory, the system is modeled as rigid-body structures connected by linear elastic elements, such as complex actuators and bearings. The full dynamic properties of each element are determined experimentally or theoretically, then integrated into the program as inertial and stiffness matrices. Utilizing this program, the theoretical and experimental verification of the vibratory behavior of a double-multilayer monochromator support and positioning system is presented. Results of parametric design studies that investigate the influence of support floor dynamics and highlight important design issues are also presented. Overall, good matches between theory and experiment demonstrate the effectiveness of the program as a dynamic modeling tool.

  18. Vibratory Loads Data from a Wind-Tunnel Test of Structurally Tailored Model Helicopter Rotors

    NASA Technical Reports Server (NTRS)

    Yeager, William T., Jr.; Hamouda, M-Nabil H.; Idol, Robert F.; Mirick, Paul H.; Singleton, Jeffrey D.; Wilbur, Matthew L.

    1991-01-01

    An experimental study was conducted in the Langley Transonic Dynamics Tunnel to investigate the use of a Bell Helicopter Textron (BHT) rotor structural tailoring concept, known as rotor nodalization, in conjunction with advanced blade aerodynamics as well as to evaluate rotor blade aerodynamic design methodologies. A 1/5-size, four-bladed bearingless hub, three sets of Mach-scaled model rotor blades were tested in forward flight from transition up to an advance ratio of 0.35. The data presented pertain only to the evaluation of the structural tailoring concept and consist of fixed-system and rotating system vibratory loads. These data will be useful for evaluating the effects of tailoring blade structural properties on fixed-system vibratory loads, as well as validating analyses used in the design of advanced rotor systems.

  19. A substrate energy dissipation mechanism in in-phase and anti-phase micromachined z-axis vibratory gyroscopes

    NASA Astrophysics Data System (ADS)

    Trusov, Alexander A.; Schofield, Adam R.; Shkel, Andrei M.

    2008-09-01

    This paper analyzes energy dissipation mechanisms in vacuum-operated in-phase and anti-phase actuated micromachined z-axis vibratory gyroscopes. The type of actuation is experimentally identified as the key factor to energy dissipation. For in-phase devices, dissipation through the die substrate is the dominant energy loss mechanism. This damping mechanism depends strongly on the die attachment method; rigid die attachment minimizes the loss of energy at the cost of reduced vibrational and stress isolation. For anti-phase actuated devices, dissipation through the substrate is suppressed and immunity to external vibrations is provided. However, even in anti-phase actuated devices fabrication imperfections introduce structural non-symmetry, enabling dissipation of energy through the die substrate due to momentum imbalance. Based on the experimental investigation, an analytical model for energy dissipation through the die substrate is proposed and used to study the effects of the actuation type, die attachment and fabrication imperfections. The limiting Q-factor for in-phase devices is generally below 20 × 103 while Q-factors much higher than 100 × 103 can be achieved with balanced anti-phase actuated gyroscopes.

  20. Effect of changing speckles in digital holography on measurements of static and vibratory displacements.

    PubMed

    Stetson, Karl A

    2016-06-01

    This paper presents a study of speckle effects in measurements of static and vibratory displacements by digital holography. Such effects are shown to arise from changes in speckle fields that often occur between holographic recordings. These may be between recording holograms before and after static deformations or changes in sets of holograms recorded for vibration measurement. If the images do not change between such recordings, the effects appear to be limited mainly to round-off errors. PMID:27411207

  1. Recovery of Vibratory Function After Vocal Fold Microflap in a Rabbit Model

    PubMed Central

    Kojima, Tsuyoshi; Mitchell, Joshua R.; Garrett, C. Gaelyn; Rousseau, Bernard

    2015-01-01

    Objectives/Hypothesis The purpose of this study was to evaluate the return of vibratory function and restoration of vibration amplitude and symmetry after vocal fold microflap surgery. Study Design Prospective in vivo animal model. Methods Microflap surgery was performed on 30 New Zealand white breeder rabbits. The left vocal fold received a 3-mm epithelial incision and mucosal elevation, while the contralateral vocal fold was left intact to serve as an internal control. Quantitative analysis of amplitude ratio and lateral phase difference were measured using high-speed laryngeal imaging at a frame rate of 10,000 frames per second from animals undergoing evoked phonation on postoperative days 0, 1, 3, 5, and 7. Results Quantitative measures revealed a significantly reduced amplitude ratio and lateral phase difference on day 0 after microflap. These impairments of vibratory function on day 0 were associated with separation of the vocal fold’s bodycover layer. Amplitude ratio increased significantly by day 3 after microflap, with further increases in vibration amplitude on days 5 and 7. While the amplitude ratio improved significantly on day 3, lateral phase difference decreased significantly on day 3, and returned to normal on days 5 and 7. Conclusions High-speed laryngeal imaging was used to investigate the natural time course of postmicroflap recovery of vibratory function. Results revealed the restoration of vibration amplitude and lateral phase difference by days 3 to 7 after microflap. The time period of improved vibratory function observed in this study coincides with the end of the well-documented inflammatory phase of vocal fold wound repair. PMID:23901003

  2. Hydrostatic Vibratory Drive of the Test Stand for Excitation of the Amplitude-Modulated Vibrations

    NASA Astrophysics Data System (ADS)

    Nizhegorodov, A. I.; Gavrilin, A. N.; Moyzes, B. B.

    2016-01-01

    The article reviews the problems arising during the development of the test stand hydrostatic vibratory drive, which synthesize controlled amplitude-modulated vibrations required testing of vibration strength and vibrostability of technological devices. The newly developed modification can adequately simulate the transport vibration and vibration of the operating power-supply units of technological machinery vibration by means of implementing of a continuous frequency spectrum of the vibration exposure in the desired frequency range.

  3. Mechanical Assessment of the Drep Shield Subject to Vibratory Motion and Dynamic and Static Rock Loading

    SciTech Connect

    R.C. Quittmeyer

    2005-11-16

    The purpose of the drip shield (DS) is to divert water that may seep into emplacement drifts from contacting the waste packages, and to protect the waste packages from impact or static loading from rockfall. The objective of this document is to summarize, into one location, the results of a series of supporting engineering calculations that were developed to study the effect of static and dynamic loads on the mechanical performance of the DS. The potential DS loads are a result of: (1) Potential earthquake vibratory ground motion, and resulting interaction of the DS, waste package and pallet, and drift invert; (2) Dynamic impacts of rockfall resulting from emplacement drift damage as a result of earthquake vibratory motion; and (3) Static load of the caved rock rubble that may come to rest on the DS as a result of vibratory motion or from time-dependent yielding of the rock mass surrounding the emplacement drift. The potential mechanical failure mechanisms that may result from these loads include: (1) Overturning and/or separation of the interlocking DS segments; (2) Loss of structural integrity and stability of the DS, including excessive deformation or buckling; and (3) Localized damage to the top and side-wall plates of the DS. The scope of this document is limited to summarizing results presented in the supporting calculations in the areas of analysis of the potential for DS collapse, and determination of the damaged surface area of the DS plates. New calculations are presented to determine whether or not separation of DSs occur under vibratory motion.

  4. Phytotherapy for pain relief.

    PubMed

    Zareba, Grazyna

    2009-06-01

    Pain is considered the third most common healthcare problem disabling more individuals than heart disease and cancer together. Although pharmacological pain management offers a significant relief in several pain-related diseases, many patients turn to its supplementation with complementary and alternative medicine. Botanicals used in pain therapy can contribute to restoring the quality of life to a patient and may effect and enhance conventional pain management. Herbal analgesic use in several pain-related diseases such as rheumatologic diseases, back pain, cancer, diabetic peripheral neuropathy and migraine will be discussed. In addition, this review describes botanicals with known analgesic activity for which randomized, placebo-controlled, double-blind trials assessing their efficacy in different pain-related diseases have been published and which have been recently evaluated in many systematic reviews with well-described methodology. PMID:19649334

  5. Effects of vibratory stimulation-induced kinesthetic illusions on the neural activities of patients with stroke

    PubMed Central

    Kodama, Takayuki; Nakano, Hideki; Ohsugi, Hironori; Murata, Shin

    2016-01-01

    [Purpose] This study evaluated the influence of vibratory stimulation-induced kinesthetic illusion on brain function after stroke. [Subjects] Twelve healthy individuals and 13 stroke patients without motor or sensory loss participated. [Methods] Electroencephalograms were taken at rest and during vibratory stimulation. As a neurophysiological index of brain function, we measured the μ-rhythm, which is present mainly in the kinesthetic cortex and is attenuated by movement or motor imagery and compared the data using source localization analyses in the Standardized Low Resolution Brain Electromagnetic Tomography (sLORETA) program. [Results] At rest, μ-rhythms appeared in the sensorimotor and supplementary motor cortices in both healthy controls and stroke patients. Under vibratory stimulation, no μ-rhythm appeared in the sensorimotor cortex of either group. Moreover, in the supplementary motor area, which stores the motor imagery required for kinesthetic illusions, the μ-rhythms of patients were significantly stronger than those of the controls, although the μ-rhythms of both groups were reduced. Thus, differences in neural activity in the supplementary motor area were apparent between the subject groups. [Conclusion] Kinesthetic illusions do occur in patients with motor deficits due to stroke. The neural basis of the supplementary motor area in stroke patients may be functionally different from that found in healthy controls. PMID:27065525

  6. Gearbox fault diagnosis based on deep random forest fusion of acoustic and vibratory signals

    NASA Astrophysics Data System (ADS)

    Li, Chuan; Sanchez, René-Vinicio; Zurita, Grover; Cerrada, Mariela; Cabrera, Diego; Vásquez, Rafael E.

    2016-08-01

    Fault diagnosis is an effective tool to guarantee safe operations in gearboxes. Acoustic and vibratory measurements in such mechanical devices are all sensitive to the existence of faults. This work addresses the use of a deep random forest fusion (DRFF) technique to improve fault diagnosis performance for gearboxes by using measurements of an acoustic emission (AE) sensor and an accelerometer that are used for monitoring the gearbox condition simultaneously. The statistical parameters of the wavelet packet transform (WPT) are first produced from the AE signal and the vibratory signal, respectively. Two deep Boltzmann machines (DBMs) are then developed for deep representations of the WPT statistical parameters. A random forest is finally suggested to fuse the outputs of the two DBMs as the integrated DRFF model. The proposed DRFF technique is evaluated using gearbox fault diagnosis experiments under different operational conditions, and achieves 97.68% of the classification rate for 11 different condition patterns. Compared to other peer algorithms, the addressed method exhibits the best performance. The results indicate that the deep learning fusion of acoustic and vibratory signals may improve fault diagnosis capabilities for gearboxes.

  7. Vibratory perception thresholds at the clavicle in patients with spinal cord injury.

    PubMed Central

    Herszkowicz, I; Berić, A; Lindblom, U

    1986-01-01

    Vibratory perception thresholds were measured by an electromagnetic device applied over the clavicles of 64 patients with spinal cord injuries. Patients with neurological levels of C5 and below had low threshold values (0.63 +/- 0.23 micron of vibration amplitude; mean +/- SD) which were used as reference values. The patients with a neurological level of C1/2 had very high vibratory thresholds bilaterally (above 11.0 micron). Patients with C2/3-3/4 neurological levels also had significantly elevated thresholds (2.56 +/- 2.01 micron), while those with C4-C4/5 levels did not differ significantly from the reference group. The results agree with earlier observations that the C4 segment innervates the clavicle and imply that patients with a lesion at or above C4 may have elevated clavicular vibratory thresholds. It is concluded that vibrametry, a non-invasive technique, is applicable in patients with spinal cord injury and disease, and can be useful for assessment of sensory level and particularly for follow-up of such patients. PMID:3760897

  8. Simulation of surface EMG for the analysis of muscle activity during whole body vibratory stimulation.

    PubMed

    Fratini, Antonio; Bifulco, Paolo; Romano, Maria; Clemente, Fabrizio; Cesarelli, Mario

    2014-01-01

    This study aims to reproduce the effect of motor-unit synchronization on surface EMG recordings during vibratory stimulation to highlight vibration evoked muscle activity. The authors intended to evaluate, through numerical simulations, the changes in surface EMG spectrum in muscles undergoing whole body vibration stimulation. In some specific bands, in fact, vibration induced motion artifacts are also typically present. In addition, authors meant to compare the simulated EMGs with respect to real recordings in order to discriminate the effect of synchronization of motor units discharges with vibration frequencies from motion artifacts. Computations were performed using a model derived from previous studies and modified to consider the effect of vibratory stimulus, the motor unit synchronization and the endplates-electrodes relative position on the EMG signal. Results revealed that, in particular conditions, synchronization of MUs' discharge generates visible peaks at stimulation frequency and its harmonics. However, only a part of the total power of surface EMGs might be enclosed within artifacts related bands (± 1 Hz centered at the stimulation frequency and its superior harmonics) even in case of strong synchronization of motor units discharges with the vibratory stimulus. PMID:24183387

  9. Mapping Of Textile Surface Relief

    NASA Astrophysics Data System (ADS)

    Costa, Manuel F. P. C. M.; Almeida, Jose B.

    1989-01-01

    We describe a system which is capable of mapping the relief of textile surfaces, by non contact optical means, designed to be used in textile engineering laboratories to study the alterations produced in fabrics by the action of dyes, shock, stress, and so on. The specific nature of these materials precludes the use of conventional profiling systems, which led us to develop a new method with the necessary versatility but reasonably immune to dispersion, diffraction and speckle, phenomena which usually make very difficult the application of optical methods to this situation. The method is based on the horizontal shift of the bright spot on an horizontal surface when this is illuminated with an oblique beam and moved vertically. In order to make the profilometry the sample is swept by an oblique laser beam and the bright spot position is compared with a reference position. The system is thus formed by an HeNe laser focused onto a reference surface (sample support) endowed of bidirectional motion obtained by two stepping motors which are controlled by a 8051 microcomputer that will also control the data acquisition and processing system, and it's forwarding to the working microcomputer. The laser beam incidence angle, the focusing system and the reception objective can be changed to increase the system fickleness.

  10. Force Augmentation for Relief Valve

    NASA Technical Reports Server (NTRS)

    Luger, J.

    1982-01-01

    Simple design change for poppet relief valve enables flow through valve to exert additional force to help keep valve open. Although originally intended for relief valves for liquid oxygen and liquid nitrogen in Space Shuttle orbiter, concept is applicable to pressure-or flow-actuated valves for wide range of fluids and temperatures.

  11. Transcutaneous electrical nerve stimulation (TENS) as compared to placebo TENS for the relief of acute oro-facial pain.

    PubMed

    Hansson, P; Ekblom, A

    1983-02-01

    The present paper describes the effect of high frequency, low frequency and placebo TENS on acute oro-facial pain in 62 patients, attending to an emergency clinic for dental surgery; they had all suffered pain for 1-4 days. The patients were randomly assigned to one of three groups receiving either high frequency (100 Hz), low frequency (2 Hz) or placebo TENS. In the two groups receiving TENS (42 patients) 16 patients reported a reduction in pain intensity exceeding 50%; out of these 16 patients, 4 patients reported complete relief of pain. In the placebo group (20 patients) 2 patients reported a pain reduction of more than 50%; out of these 2 patients, none reported a complete pain relief. Mechanical vibratory stimulation augmented the pain reduction obtained by TENS in 5 out of 10 patients. PMID:6601789

  12. Temporal processing of vibratory communication signals at the level of ascending interneurons in Nezara viridula (Hemiptera: Pentatomidae).

    PubMed

    Zorović, Maja

    2011-01-01

    During mating, males and females of N. viridula (Heteroptera: Pentatomidae) produce sex- and species-specific calling and courtship substrate-borne vibratory signals, grouped into songs. Recognition and localization of these signals are fundamental for successful mating. The recognition is mainly based on the temporal pattern, i.e. the amplitude modulation, while the frequency spectrum of the signals usually only plays a minor role. We examined the temporal selectivity for vibratory signals in four types of ascending vibratory interneurons in N. viridula. Using intracellular recording and labelling technique, we analyzed the neurons' responses to 30 pulse duration/interval duration (PD/ID) combinations. Two response arrays were created for each neuron type, showing the intensity of the responses either as time-averaged spike counts or as peak instantaneous spike rates. The mean spike rate response arrays showed preference of the neurons for short PDs (below 600 ms) and no selectivity towards interval duration; while the peak spike rate response arrays exhibited either short PD/long ID selectivity or no selectivity at all. The long PD/short ID combinations elicited the weakest responses in all neurons tested. No response arrays showed the receiver preference for either constant period or duty cycle. The vibratory song pattern selectivity matched the PD of N. viridula male vibratory signals, thus pointing to temporal filtering for the conspecific vibratory signals already at level of the ascending interneurons. In some neurons the responses elicited by the vibratory stimuli were followed by distinct, regular oscillations of the membrane potential. The distance between the oscillation peaks matched the temporal structure of the male calling song, indicating a possible resonance based mechanism for signal recognition. PMID:22053216

  13. Temporal Processing of Vibratory Communication Signals at the Level of Ascending Interneurons in Nezara viridula (Hemiptera: Pentatomidae)

    PubMed Central

    Zorović, Maja

    2011-01-01

    During mating, males and females of N. viridula (Heteroptera: Pentatomidae) produce sex- and species-specific calling and courtship substrate-borne vibratory signals, grouped into songs. Recognition and localization of these signals are fundamental for successful mating. The recognition is mainly based on the temporal pattern, i.e. the amplitude modulation, while the frequency spectrum of the signals usually only plays a minor role. We examined the temporal selectivity for vibratory signals in four types of ascending vibratory interneurons in N. viridula. Using intracellular recording and labelling technique, we analyzed the neurons' responses to 30 pulse duration/interval duration (PD/ID) combinations. Two response arrays were created for each neuron type, showing the intensity of the responses either as time-averaged spike counts or as peak instantaneous spike rates. The mean spike rate response arrays showed preference of the neurons for short PDs (below 600 ms) and no selectivity towards interval duration; while the peak spike rate response arrays exhibited either short PD/long ID selectivity or no selectivity at all. The long PD/short ID combinations elicited the weakest responses in all neurons tested. No response arrays showed the receiver preference for either constant period or duty cycle. The vibratory song pattern selectivity matched the PD of N. viridula male vibratory signals, thus pointing to temporal filtering for the conspecific vibratory signals already at level of the ascending interneurons. In some neurons the responses elicited by the vibratory stimuli were followed by distinct, regular oscillations of the membrane potential. The distance between the oscillation peaks matched the temporal structure of the male calling song, indicating a possible resonance based mechanism for signal recognition. PMID:22053216

  14. Compression relief engine brake

    SciTech Connect

    Meneely, V.A.

    1987-10-06

    A compression relief brake is described for four cycle internal-combustion engines, comprising: a pressurized oil supply; means for selectively pressurizing a hydraulic circuit with oil from the oil supply; a master piston and cylinder communicating with a slave piston and cylinder via the hydraulic circuit; an engine exhaust valve mechanically coupled to the engine and timed to open during the exhaust cycle of the engine the exhaust valve coupled to the slave piston. The exhaust valve is spring-based in a closed state to contact a valve seat; a sleeve frictionally and slidably disposed within a cavity defined by the slave piston which cavity communicates with the hydraulic circuit. When the hydraulic circuit is selectively pressurized and the engine is operating the sleeve entraps an incompressible volume of oil within the cavity to generate a displacement of the slave piston within the slave cylinder, whereby a first gap is maintained between the exhaust valve and its associated seat; and means for reciprocally activating the master piston for increasing the pressure within the previously pressurized hydraulic circuit during at least a portion of the expansion cycle of the engine whereby a second gap is reciprocally maintained between the exhaust valve and its associated seat.

  15. 47 CFR 69.727 - Regulatory relief.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... customer. (b) Phase II relief. Upon satisfaction of the Phase II triggers specified in § 69.709(c) or § 69... Pricing Flexibility § 69.727 Regulatory relief. (a) Phase I relief. Upon satisfaction of the Phase...

  16. 47 CFR 69.727 - Regulatory relief.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... customer. (b) Phase II relief. Upon satisfaction of the Phase II triggers specified in § 69.709(c) or § 69... Pricing Flexibility § 69.727 Regulatory relief. (a) Phase I relief. Upon satisfaction of the Phase...

  17. 47 CFR 69.727 - Regulatory relief.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... customer. (b) Phase II relief. Upon satisfaction of the Phase II triggers specified in § 69.709(c) or § 69... Pricing Flexibility § 69.727 Regulatory relief. (a) Phase I relief. Upon satisfaction of the Phase...

  18. 47 CFR 69.727 - Regulatory relief.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... customer. (b) Phase II relief. Upon satisfaction of the Phase II triggers specified in § 69.709(c) or §69... Pricing Flexibility § 69.727 Regulatory relief. (a) Phase I relief. Upon satisfaction of the Phase...

  19. 47 CFR 69.727 - Regulatory relief.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... customer. (b) Phase II relief. Upon satisfaction of the Phase II triggers specified in §§ 69.709(c) or 69... Pricing Flexibility § 69.727 Regulatory relief. (a) Phase I relief. Upon satisfaction of the Phase...

  20. Numerical investigation of soil plugging effect inside sleeve of cast-in-place piles driven by vibratory hammers in clays.

    PubMed

    Xiao, Yong Jie; Chen, Fu Quan; Dong, Yi Zhi

    2016-01-01

    During driving sleeve of cast-in-place piles by vibratory hammers, soils were squeezed into sleeve and then soil plugging was formed. The physic-mechanical properties of the soil plug have direct influence on the load transmission between the sleeve wall and soil plug. Nevertheless, the researches on this issue are insufficient. In this study, finite element and infinite element coupling model was introduced, through the commercial code ABAQUS, to simulate the full penetration process of the sleeve driven from the ground surface to the desired depth by applying vibratory hammers. The research results indicated that the cyclic shearing action decreases both in soil shear strength and in granular cementation force when the sleeve is driven by vibratory hammers, which leads to a partially plugged mode of the soil plug inside the sleeve. Accordingly, the penetration resistance of sleeve driven by vibratory hammers is the smallest compared to those by other installation methods. When driving the sleeve, the annular soil arches forming in the soil plug at sleeve end induce a significant rise in the internal shaft resistance. Moreover, the influence of vibration frequencies, sleeve diameters, and soil layer properties on the soil plug was investigated in detail, and at the same time improved formulas were brought forward to describe the soil plug resistance inside vibratory driven sleeve. PMID:27386238

  1. Vibratory sources as compound stimuli for the octavolateralis systems: Dissection of specific stimulation channels using multiple behavioral approaches

    PubMed Central

    Braun, Christopher B.; Coombs, Sheryl

    2010-01-01

    An underwater vibratory source simultaneously presents acoustic and hydrodynamic disturbances. Because vibratory dipole sources are poor sonic projectors, most researchers have assumed that such sources are of greatest relevance to the lateral line system (LL). Both hydroacoustic principles and empirical studies have shown that vibratory dipole sources are also a potent stimulus to the inner ear of fishes. Responses to vibratory sources in mottled sculpin (Cottus bairdi) were assessed using unconditioned orienting, differential and non-differential-classical conditioning. Orienting responses are dominated by LL inputs and eliminated by LL pharmacological inactivation. Simple conditioning depends on inputs from other systems and was not affected by LL inactivation. Differential conditioning alters behavioral control, and sculpin could be conditioned to ignore substrate borne vibrations and respond only to hydroacoustic stimulation of the ear. The lateral line and inner ear of mottled sculpin do not necessarily exhibit range fractionation, as both systems operate over a similar distance from the animal (within 1.5 body lengths) and respond to many of the same sources. Vibratory dipole sources generate compound stimuli that simultaneously activate multiple octavolateralis systems, and animals make use of the channels differentially under different behavioral tasks. PMID:20384404

  2. Inexpensive Pressure-Relief Valve

    NASA Technical Reports Server (NTRS)

    Theordore, E. A.

    1985-01-01

    Simple device vents excess low-pressure gas. Inexpensive pressure relief valve built from polyvinylchloride pipe. Valve suitable for low pressure-- 25 to 50 cm of mercury-- and flow rates up to 14 m3/min.

  3. High-performance micromachined vibratory rate- and rate-integrating gyroscopes

    NASA Astrophysics Data System (ADS)

    Cho, Jae Yoong

    The performance of vibratory micromachined gyroscopes has been continuously improving for the past two decades. However, to further improve performance of the MEMS gyroscope in harsh environment, it is necessary for gyros to reduce the sensitivity to environmental parameters, including vibration and temperature change. In addition, conventional rate-mode MEMS gyroscopes have limitation in performance due to tradeoff between resolution, bandwidth, and full-scale range. In this research, we aim to reduce vibration sensitivity by developing gyros that operate in the balanced mode. The balanced mode creates zero net momentum and reduces energy loss through an anchor. The gyro can differentially cancel measurement errors from external vibration along both sensor axes. The vibration sensitivity of the balanced-mode gyroscope including structural imbalance from microfabrication reduces as the absolute difference between in-phase parasitic mode and operating mode frequencies increases. The parasitic sensing mode frequency is designed larger than the operating mode frequency to achieve both improved vibration insensitivity and shock resistivity. A single anchor is used in order to minimize thermoresidual stress change. We developed two gyroscope based on these design principles. The Balanced Oscillating Gyro (BOG) is a quad-mass tuning-fork rate gyroscope. The relationship between gyro design and modal characteristics is studied extensively using finite element method (FEM). The gyro is fabricated using the planar Si-on-glass (SOG) process with a device thickness of 100microm. The BOG is evaluated using the first-generation analog interface circuitry. Under a frequency mismatch of 5Hz between driving and sense modes, the angle random walk (ARW) is measured to be 0.44°/sec/✓Hz. The performance is limited by quadrature error and low-frequency noise in the circuit. The Cylindrical Rate-Integrating Gyroscope (CING) operates in whole-angle mode. The gyro is completely

  4. Unilateral contact induced blade/casing vibratory interactions in impellers: Analysis for rigid casings

    NASA Astrophysics Data System (ADS)

    Batailly, Alain; Meingast, Markus; Legrand, Mathias

    2015-02-01

    This contribution addresses the vibratory analysis of unilateral-contact induced structural interactions between a bladed impeller and its surrounding rigid casing. Such assemblies can be found in helicopter or small aircraft engines for instance and the interactions of interest shall arise due to the always tighter operating clearances between the rotating and stationary components. The investigation is conducted by extending to cyclically symmetric structures an in-house time-marching based tool dedicated to unilateral contact occurrences in turbomachines. The main components of the considered impeller together with the associated assumptions and modelling principles considered in this work are detailed. Typical dynamical features of cyclically symmetric structures, such as the aliasing effect and frequency clustering are explored in this nonlinear framework by means of thorough frequency-domain analyses and harmonic trackings of the numerically predicted impeller displacements. Additional contact maps highlight the existence of critical rotational velocities at which displacements potentially reach high amplitudes due to the synchronization of the bladed assembly vibratory pattern with the shape of the rigid casing. The proposed numerical investigations are also compared to a simpler and (almost) empirical criterion: it is suggested, based on nonlinear numerical simulations with a linear reduced order model of the impeller and a rigid casing, that this criterion may miss important critical velocities emanating from the unfavorable combination of aliasing and contact-induced higher harmonics in the vibratory response of the impeller. Overall, this work suggests a way to enhance guidelines to improve the design of impellers in the context of nonlinear and nonsmooth dynamics.

  5. Mating behaviour and vibratory signalling in non-hearing cave crickets reflect primitive communication of Ensifera.

    PubMed

    Stritih, Nataša; Čokl, Andrej

    2012-01-01

    In Ensifera, the lack of well-supported phylogeny and the focus on acoustic communication of the terminal taxa hinders understanding of the evolutionary history of their signalling behaviour and the related sensory structures. For Rhaphidophoridae, the most relic of ensiferans following morphology-based phylogenies, the signalling modes are still unknown. Together with a detailed description of their mating process, we provide evidence on vibratory signalling for the sympatric European species Troglophilus neglectus and T. cavicola. Despite their temporal shift in reproduction, the species' behaviours differ significantly. Signalling by abdominal vibration constitutes an obligatory part of courtship in T. neglectus, while it is absent in T. cavicola. Whole-body vibration is expressed after copulation in both species. While courtship signalling appears to stimulate females for mating, the function of post-copulation signals remains unclear. Mating and signalling of both species were found to take place in most cases on bark, and less frequently on other available substrates, like moss and rock. The signals' frequency spectra were substrate dependent, but with the dominant peak always expressed below 120 Hz. On rock, the intensity of T. neglectus courtship signals was below the species' physiological detection range, presumably constraining the evolution of such signalling in caves. The species' behavioural divergence appears to reflect their divergent mating habitats, in and outside caves. We propose that short-range tremulation signalling in courtship, such as is expressed by T. neglectus, represents the primitive mode and context of mechanical signalling in Ensifera. The absence of high-frequency components in the signals may be related to the absence of the crista acoustica homologue (CAH) in the vibratory tibial organ of Rhaphidophoridae. This indirectly supports the hypothesis proposing that the CAH, as an evolutionary precursor of the ear, evolved in Ensifera

  6. Surface relief of TiNiCu thin films

    NASA Astrophysics Data System (ADS)

    Cheng, Xiulan; Xu, Dong; Cai, Bingchu; Wang, Li; Chen, Jian; Li, Gang; Xu, Shi

    2001-10-01

    TiNiCu thin film shape memory alloys are potential materials for microactuator. In our previous research, the various natural surface relief of crystallized TiNiCu thin film was observed, and it was related with compositions and the sputtering deposition conditions. In order to understand the origin and nature of the surface relief, the temperature-resistance measurement, X-ray diffraction and atomic fore microscopic study were performed. For Ti48.4Ni46.3Cu5.3 thin films, the transformation temperatures are below 0 degree(s)C, and the natural surface is smooth at 12 degree(s)C since the microstructure is austenite. For Ti51Ni44Cu5 thin films, two typical kinds of surface relief, e.g., chrysanthemum and rock candy, were observed at 12 degree(s)C. The chrysanthemum on the martensitic block relief is Ti-rich G.P. zone and will not disappear in thermal cycles later. It is also found that the Ti-rich G.P. zone is related with the thin films formed under lower sputtering Ar pressure. The rock candy relief is a typical martensite surface relief and will disappear when heating to the austenite phase. During crystallization process, the inherent compressive stress introduced under the condition of higher sputtering pressure is helpful to the transition from G.P. zones to Ti2(NiCu) precipitates and the increase of the transformation temperatures.

  7. Process for forming integral edge seals in porous gas distribution plates utilizing a vibratory means

    NASA Technical Reports Server (NTRS)

    Feigenbaum, Haim (Inventor); Pudick, Sheldon (Inventor)

    1988-01-01

    A process for forming an integral edge seal in a gas distribution plate for use in a fuel cell. A seal layer is formed along an edge of a porous gas distribution plate by impregnating the pores in the layer with a material adapted to provide a seal which is operative dry or when wetted by an electrolyte of a fuel cell. Vibratory energy is supplied to the sealing material during the step of impregnating the pores to provide a more uniform seal throughout the cross section of the plate.

  8. Analysis of compensation for a g-sensitivity scale-factor error for a MEMS vibratory gyroscope

    NASA Astrophysics Data System (ADS)

    Park, Byung Su; Han, KyungJun; Lee, SangWoo; Yu, MyeongJong

    2015-11-01

    In this paper, we present recent work on the g-sensitivity error of the MEMS vibratory gyroscope. Generally, the g-sensitivity error has been ignored in the use of commercial MEMS vibratory gyroscopes, but it deserves our attention if we are to achieve tactical grade performance for military applications. First, we mathematically show the reason the g-sensitivity error occurs as an additional scale-factor error during the use of MEMS vibratory gyroscopes. Then, we estimate the g-sensitivity error using FEM simulation and verify it by experiment using a centrifugal machine. Consequently, we propose a compensation model to accommodate the g-sensitivity error of a gyroscope and confirm the theoretical prediction with experimental results.

  9. Investigation on Multi-Physics Simulation-Based Virtual Machining System for Vibratory Finishing of Integrally Bladed Rotors (IBRS)

    NASA Astrophysics Data System (ADS)

    Achiamah-Ampomah, N.; Cheng, Kai

    2016-02-01

    An investigation was carried out to improve the slow surface finishing times of integrally bladed rotors (IBRs) in the aerospace industry. Traditionally they are finished by hand, or more currently by abrasive flow machining. The use of a vibratory finishing technique to improve process times has been suggested; however as a largely empirical process, very few studies have been done to improve and optimize the cycle times, showing that critical and ongoing research is still needed in this area. An extensive review of the literature was carried out, and the findings used to identify the key parameters and model equations which govern the vibratory process. Recommendations were made towards a multi-physics-based simulation model, as well as projections made for the future of vibratory finishing and optimization of surface finishes and cycle times.

  10. Making and suspension capabilities of vibratory agitators in a slab tank

    SciTech Connect

    Ramsey, C.J.; Kyser, E.A. III; Tatterson, G.B.

    1988-12-31

    Seven different vibratory agitators, consisting of single and dual flat blade configurations or dual angle blade configurations, were studied for their ability to produce mixing and solid suspension in a slab tank. The mixing behavior of the various configurations was recorded on video tape, and mixing times were measured as the time needed to disperse injected dye. The solid suspension tests, using ash tray sand, were conducted to determine the minimum stroke frequency of the agitators needed for complete off-bottom suspension. The mixing studies demonstrated that vibratory agitation produced strong vertical fluid motion, good bulk circulation and dispersion in the liquid. The effects of stroke frequency, n; amplitude, a; blade width, w; blade clearance, c; and liquid depth, h, on mixing time, {theta}, were studied. Single blade geometries produced complete mixing in the least number of strokes. The most effective geometry, in terms of both mixing and solid suspension, was a single flat blade with minimum off-bottom clearance and a blade width/tank thickness ratio, w/T, of 0.74 at the maximum stroke amplitude of 51 mm.

  11. Effect On The Processing Characteristics Of ZnO Varistors Produced Using Vibratory Milling

    NASA Astrophysics Data System (ADS)

    Kelleher, M. C.; Hashmi, M. S. J.

    2011-01-01

    Each manufacturing stage in the production of zinc oxide varistors from powder preparation to the final encapsulated device is important not only for the formation of the varistor component with optimum microstructure and thus electrical characteristics but also for avoiding the introduction of flaws and reduced yield. In this paper the authors describe and discuss the effect of multi-elemental oxide additives having been milled for different durations using a vibratory mill with cylindrical zirconia media on the powder characteristics of the subsequent processing stages. A commercial ZnO varistor formulation was used. The subsequent processing stages that are given particular attention include first spray drying and second milling. The characteristics include agglomerate size, powder density and elemental uniformity of the first spray-dried powders, and particle size, specific surface area, zirconium concentration and pore size of the second milled powders. They were evaluated using laser diffraction, scanning electron microscopic, mercury porosimetry, Brunauer, Emmett and Teller (BET) and inductively coupled plasma (ICP) analysis. Some interesting correlations are observed between the powder properties and vibratory milling durations of the mixed metal oxide additives (MMOA).

  12. Conjectural bifurcation analysis of the contact-induced vibratory response of an aircraft engine blade

    NASA Astrophysics Data System (ADS)

    Batailly, Alain; Legrand, Mathias; Millecamps, Antoine; Garcin, François

    2015-07-01

    This paper deals with the numerical investigation of the unilateral contact-induced dynamics of a turbomachine blade rotating within a perfectly rigid yet distorted casing. This investigation is motivated by unelucidated vibratory behaviours observed experimentally. The simulations are based on an in-house time-marching strategy incorporating Lagrange multipliers for the unilateral contact treatment, as well as centrifugal stiffening and abradable coating removal. Significant extensions are proposed through the implementation of (1) aerodynamic loading on the blade and (2) post-processing techniques involving the empirical mode decomposition which provides fruitful insights on important transient phenomena. A thorough bifurcation analysis with and without aerodynamic loading highlights the existence of flip bifurcations with period-doubling and period-halving sequences over a broad angular speed range. Numerical simulations with external aerodynamic loading yield quasi-periodic and likely to be chaotic motions that could not be observed under vacuum. The proposed numerical investigations underline the key role of the aerodynamic loading in the blade dynamics and suggest that unexplained experimental vibratory behaviours are related to the vacuum conditions of the experiment.

  13. An Overview of A Perturbation Analysis for Uni-directionally Coupled Vibratory Gyroscopes

    NASA Astrophysics Data System (ADS)

    Vu, Huy; Palacios, Antonio; In, Visarath; Longhini, Patrick; Neff, Joseph

    2011-04-01

    The complex behaviours of gyroscope systems have been scientifically researched and thoroughly studied for decades. Most of scientific research involving gyroscopes specifically concentrates on studying the designs and fabrications at the circuitry level. Although gaining a recent popularity with the low cost of MEMS device that offers an attractive approach for gyroscope fabrications, its performance is far from meeting the requirements for an inertial grade guidance system. To improve the performance, our current research is theoretically focusing upon investigating the dynamics of vibratory gyroscopes coupled in a ring configuration. Particularly, a certain topology of arrangements among coupled gyroscopes can be designed and studied to enhance robustness. The main operation depends mostly on an external source for a stable oscillation in the drive axis, while an oscillatory motion in the sense axis, which is used to detect an angular rate of rotation, is enabled through the transfers of energy from the drive via the Coriolis force. With the mathematical model depicted as Duffing oscillators, however, by adding a certain coupling among gyroscopes, a similar behavior to a Duffing oscillator is expected, only with more complicated dynamics at a higher dimension. A number of Perturbation methods have popularly been carried out, to seek for a general asymptotic solution of typical Duffing oscillators. In this work as an overview, the two-time scale Perturbation expansion is asymptotically applied on the uni-directionally coupled vibratory gyroscopes to find an analytical solution which is then compared to the numerical one.

  14. Structural-Acoustic Coupling Effects on the Non-Vacuum Packaging Vibratory Cylinder Gyroscope

    PubMed Central

    Xi, Xiang; Wu, Xuezhong; Wu, Yulie; Zhang, Yongmeng; Tao, Yi; Zheng, Yu; Xiao, Dingbang

    2013-01-01

    The resonant shells of vibratory cylinder gyroscopes are commonly packaged in metallic caps. In order to lower the production cost, a portion of vibratory cylinder gyroscopes do not employ vacuum packaging. However, under non-vacuum packaging conditions there can be internal acoustic noise leading to considerable acoustic pressure which is exerted on the resonant shell. Based on the theory of the structural-acoustic coupling, the dynamical behavior of the resonant shell under acoustic pressure is presented in this paper. A finite element (FE) model is introduced to quantitatively analyze the effect of the structural-acoustic coupling. Several main factors, such as sealing cap sizes and degree of vacuum which directly affect the vibration of the resonant shell, are studied. The results indicate that the vibration amplitude and the operating frequency of the resonant shell will be changed when the effect of structural-acoustic coupling is taken into account. In addition, an experiment was set up to study the effect of structural-acoustic coupling on the sensitivity of the gyroscope. A 32.4 mV/°/s increase of the scale factor and a 6.2 Hz variation of the operating frequency were observed when the radial gap size between the resonant shell and the sealing cap was changed from 0.5 mm to 20 mm. PMID:24351631

  15. Vibratory Gyro-Sensor Using Vertically Set Quartz Crystal Trident-Type Tuning Fork Resonator

    NASA Astrophysics Data System (ADS)

    Shiratori, Norihiko; YoshiroTomikawa, YoshiroTomikawa; Ohnishi, Kazumasa

    1999-05-01

    In this study we deal with a new type of vibratory gyro-sensor using a vertically set quartz crystal trident-type tuning fork resonator. The sensor is made of X-cut quartz crystal wafer formed by rotating 2° about the X-axis, applying the wire saw cutting method. The slits that form three arms are cut along the Y-axis direction. In such a trident-type tuning fork resonator, two resonance vibration modes are used: one has vibrational displacement in the vertical direction (X-axis) of the tuning fork plane and the other has that in the horizontal direction (Z‧-axis). When an angular rate (ΩY‧) around the Y‧-axis is applied to the trident-type tuning fork gyro-sensor vibrating in the V-MODE, Coriolis forces, due to the ΩY‧, are applied on the three arms in the X‧-axis direction and the H-MODE vibration is induced. Therefore, the angular rate (ΩY‧) can be determined by detecting the signals of H-MODE vibration. The experimental results have proved that the vibratory gyro-sensor that uses such a quartz crystal tuning fork resonator has good characteristics.

  16. A Study of the Temperature Characteristics of Vibration Mode Axes for Vibratory Cylinder Gyroscopes

    PubMed Central

    Wu, Yulie; Xi, Xiang; Tao, Yi; Wu, Xiaomei; Wu, Xuezhong

    2011-01-01

    The zero bias stability, which is an important performance parameter for vibratory cylinder gyroscopes, is high sensitive to temperature change. It is considered that the varying temperature makes the vibration mode axes unstable, which has significant influence on the zero bias stability. This paper will investigate this problem in detail. First, the relationships between the angular positions of vibration mode axes and the zero bias are analyzed. Secondly, the thermal-modal model of the cylinder resonator with several defects such as mass imbalance, frequency split (FS), and geometry errors are developed by ANSYS. Simulation results show that with the increase of temperature, angular positions of the vibration mode axes obviously change, which leads to a dramatic zero bias drift. Finally, several major influence factors on the angular position stability of vibration mode axes, including frequency split, geometry errors, thermal elastic modulus coefficient (TEMC) and thermal expansion coefficient (TEC) are analyzed in detail. Simulation results in this paper will be helpful for deep understanding of the drift principle of zero bias induced by temperature for vibratory cylinder gyroscopes and also be helpful for further temperature compensation or control. PMID:22164038

  17. Vibratory noise to the fingertip enhances balance improvement associated with light touch.

    PubMed

    Magalhães, Fernando Henrique; Kohn, André Fabio

    2011-03-01

    Light touch of a fingertip on an external stable surface greatly improves the postural stability of standing subjects. The hypothesis of the present work was that a vibrating surface could increase the effectiveness of fingertip signaling to the central nervous system (e.g., by a stochastic resonance mechanism) and hence improve postural stability beyond that achieved by light touch. Subjects stood quietly over a force plate while touching with their right index fingertip a surface that could be either quiescent or randomly vibrated at two low-level noise intensities. The vibratory noise of the contact surface caused a significant decrease in postural sway, as assessed by center of pressure measures in both time and frequency domains. Complementary experiments were designed to test whether postural control improvements were associated with a stochastic resonance mechanism or whether attentional mechanisms could be contributing. A full curve relating body sway parameters and different levels of vibratory noise resulted in a U-like function, suggesting that the improvement in sway relied on a stochastic resonance mechanism. Additionally, no decrease in postural sway was observed when the vibrating contact surface was attached to the subject's body, suggesting that no attentional mechanisms were involved. These results indicate that sensory cues obtained from the fingertip need not necessarily be associated with static contact surfaces to cause improvement in postural stability. A low-level noisy vibration applied to the contact surface could lead to a better performance of the postural control system. PMID:21191573

  18. [Symptom relief in terminal illness].

    PubMed

    Gleim, Martin; Schulzeck, Sabine; Siebrecht, Dieter

    2007-04-01

    It is the goal of palliative care to provide as large a relief of the disease symptoms as possible for patients, who are incurably sick, in order to improve the quality of the remaining life. Some of the symptoms can hardly be treated; others like pain, dyspnea, gastrointestinal complaints or sweating can usually be well alleviated. The condition for this is a careful evaluation of the clinical status before the treatment, in order to reach symptom relief by purposeful actions without new side effects. PMID:17457778

  19. Pressure relief valve/safety relief valve testing

    SciTech Connect

    Murray, W.A.; Hamm, E.R.; Barber, J.R.

    1994-02-01

    Pressure vessels and piping systems are protected form overpressurization by pressure relief valves. These safety features are required to be tested-inspected on some periodic basis and, in most cases witnessed by a third party inspector. As a result nonconformances found by third parties Westinghouse Hanford Company initiated a task team to develop a pressure safety program. This paper reveals their findings.

  20. 76 FR 57082 - Premium Penalty Relief; Alternative Premium Funding Target Election Relief

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-15

    ... From the Federal Register Online via the Government Publishing Office PENSION BENEFIT GUARANTY CORPORATION Premium Penalty Relief; Alternative Premium Funding Target Election Relief AGENCY: Pension Benefit... relief upon reconsideration based on the facts and circumstances. PBGC spent considerable time...

  1. Vibratory sources as compound stimuli for the octavolateralis systems: dissection of specific stimulation channels using multiple behavioral approaches.

    PubMed

    Braun, Christopher B; Coombs, Sheryl

    2010-04-01

    Underwater vibratory sources simultaneously present acoustic and hydrodynamic disturbances. Because vibratory dipole sources are poor sonic projectors, most researchers have assumed that such sources are of greatest relevance to the lateral line system. Both hydroacoustic principles and empirical studies have shown that dipole sources are also a potent stimulus to the inner ear. Responses to vibratory sources in mottled sculpin (Cottus bairdi) were assessed using unconditioned orienting, differential and nondifferential conditioning. Orienting responses are dominated by lateral line inputs and eliminated by lateral line inactivation. Simple conditioning depends on inputs from other systems and was not affected by lateral line inactivation. Differential conditioning alters behavioral control, and sculpin could be conditioned to ignore substrate-borne vibrations and respond only to hydroacoustic stimulation of the ear. The lateral line and inner ear of mottled sculpin do not necessarily exhibit range fractionation, as both systems operate over a similar distance (within 1.5 body lengths) and respond to many of the same sources. Vibratory dipole sources generate compound stimuli that simultaneously activate multiple octavolateralis systems, and sculpin make use of the channels differentially under different behavioral tasks. PMID:20384404

  2. Stress

    MedlinePlus

    ... sudden negative change, such as losing a job, divorce, or illness Traumatic stress, which happens when you ... stress, so you can avoid more serious health effects. NIH: National Institute of Mental Health

  3. Petroleum industry assists hurricane relief

    SciTech Connect

    Not Available

    1992-09-14

    This paper reports that the petroleum industry is aiding victims of last month's Hurricane Andrew with cash, clothing, food, water, and other supplies. Cash contributions announced as of last week totaled more than $2.7 million for distribution in South Florida and South Louisiana. Petroleum industry employees were collecting relief items such as bottled water and diapers for distribution in those areas.

  4. Dual rate pressure relief valve

    NASA Technical Reports Server (NTRS)

    Steeneken, J.

    1968-01-01

    Pressure relief valve vents at a slow bleed rate at one pressure level and at a higher bleed rate at a higher pressure level. The value housing contains a sleeve, inlet port, outlet port, an orifice, a ball and seat arrangement, and a belleville spring diaphragm.

  5. Morphology and physiology of vibratory interneurons in the thoracic ganglia of the southern green stinkbug Nezara viridula (L.).

    PubMed

    Zorović, Maja; Presern, Janez; Cokl, Andrej

    2008-05-10

    The central processing mechanisms of vibratory signals in small plant-dwelling insects that rely primarily on substrate-borne vibratory communication are still largely unknown. To elucidate the neural mechanisms involved in vibratory signaling, the vibration-sensitive interneurons in thoracic ganglia of the southern green stinkbug, Nezara viridula, were investigated electrophysiologically by single-cell recordings and staining. Ten types of interneurons were described and divided into four categories, based on their gross morphology. The cell body of the L-shaped CG-AC neurons is located in the metathoracic neuromere of the central ganglion, and the axon ascends contralaterally. This group comprises five types of neurons differing in their fine structure and functional properties. CG-AB neurons are dorsal unpaired median (DUM) neurons with cell bodies in the mesothoracic neuromere of the central ganglion and two axons that ascend bilaterally into the prothoracic ganglion. Group CG-L includes three types of local neurons limited to the central ganglion. With ipsilateral dendritic arborizations and contralateral axonal branching, their gross morphology is similar to that of cricket omega cells. Interneuron PTG-DC, with the cell body in the prothoracic ganglion (PTG) and a contralaterally descending axon, conveys information received by the sensory organs of the front contralateral leg to the neuropil regions of the ipsilateral middle and hind legs. Based on their frequency tuning and acceleration sensitivity, the vibratory interneurons fall into two groups: the low-frequency units are tuned to 50 Hz and the middle frequency units to 200 Hz, with their acceleration thresholds at 10(-1) m/s(2) and 5 x 10(-3) m/s(2), respectively. Their function is discussed with relevance to the vibratory communication of N. viridula. PMID:18335563

  6. Accuracy of micro powder dosing via a vibratory sieve-chute system.

    PubMed

    Besenhard, M O; Faulhammer, E; Fathollahi, S; Reif, G; Calzolari, V; Biserni, S; Ferrari, A; Lawrence, S M; Llusa, M; Khinast, J G

    2015-08-01

    This paper describes a powder dosing system with a vibratory sieve mounted on a chute that doses particles into a capsule. Vertical vibration occurred with a broad range of frequencies and amplitudes. During dosing events, the fill weight was accurately recorded via a capacitance sensor, covering the capsules and making it possible to analyze filling characteristics, that is, the fill rates and their robustness. The range of frequencies and amplitudes was screened for settings that facilitated reasonable (no blocking, no spilling) fill rates for three lactose powders. The filling characteristics were studied within this operating space. The results reveal similar operating spaces for all investigated powders. The fill rate robustness varied distinctly in the operating space, which is of prime importance for selecting the settings for continuous feeding applications. In addition, we present accurate dosing studies utilizing the knowledge about the filling characteristics of each powder. PMID:26044188

  7. Understanding the role of nonlinearities in the transduction of vibratory energy harvesters

    NASA Astrophysics Data System (ADS)

    Masana, Ravindra Shiva Charan

    The last two decades have witnessed several advances in micro-fabrication technologies and electronics, leading to the development of small, low-power devices for wireless sensing, data transmission, actuation, and medical implants. Unfortunately, the actual implementation of such devices in their respective environment has been hindered by the lack of scalable energy sources that are necessary to power and maintain them. Batteries, which remain the most commonly used power source, have not kept pace with the demands of these devices, especially in terms of energy density. In light of this challenge, the concept of vibratory energy harvesting has flourished in recent years as a possible alternative to power and maintain low-power electronics. While linear vibratory energy harvesters have received the majority of the literature's attention, a significant body of the current research activity is focused on the concept of purposeful inclusion of nonlinearities for broadband transduction. When compared to their linear resonant counterparts, nonlinear energy harvesters have a wider steady-state frequency bandwidth, leading to the common belief that they can be utilized to improve performance especially in random and non-stationary vibratory environments. This dissertation aims to critically investigate this belief by drawing a clearer picture of the role of nonlinearities in the transduction of energy harvesters and by defining the conditions under which nonlinearities can be used to enhance performance. To achieve this goal, the Thesis is divided into three parts. The first part investigates the performance of mono- and bi-stable energy harvesters under harmonic excitations and carries a detailed analysis of their relative performance. The second part investigates their response to broadband and narrowband random excitations and again analyzes their relative behavior. The third part exploits the super-harmonic resonance bands of bi-stable energy harvesters for the

  8. Sectioning of contaminated components for decontamination by vibratory finishing and electropolishing

    SciTech Connect

    Fetrow, L.K.; Allen, R.P.

    1981-09-01

    This report summarizes work conducted to develop, adapt, and evaluate a variety of techniques for sectioning glove boxes, chemical processing equipment, pipes, ducts, and other contaminated components in preparation for decontamination by vibratory finishing and electropolishing. These sectioning studies were conducted with a special 10-ft x 20-ft x 10-ft stainless-steel, walk-in glove box equipped for either hands-on operation via gloves and personnel entry, or remote operation using master slave manipulators and a bridge crane. Several sectioning techniques have been evaluated with respect to effectiveness, versatility, secondary waste generation, and capability for remote operation. The methods include wet and dry plasma arc torch cutting, mechanical sawing and nibbling, abrasive cutting, and hydraulic shearing and punching. The results of these comparison studies show that the plasma arc torch is a very rapid and effective metal cutting tool for size reduction applications. However, its use to prepare material for decontamination should be minimized because of problems with smoke generation, torch manipulation, waste generation, and entrainment of contamination. Mechanical saws eliminate all but the waste generation problem, but are very slow and labor intensive. Mechanical nibblers are fast and produce a waste form that can be decontaminated, but are limited with respect to the geometry and thickness of material that can be sectioned. High-speed abrasive saws provide high cutting rates, but produce nontreatable waste from the cut as well as from blade wear. Hydraulic shearing rapidly produces sectioned material in the small sizes required for decontamination by vibratory finishing. The kerf material also can be decontaminated. However, the glove box first must be sectioned into relatively narrow strips by one of the other techniques.

  9. An Intensified Vibratory Milling Process for Enhancing the Breakage Kinetics during the Preparation of Drug Nanosuspensions.

    PubMed

    Li, Meng; Zhang, Lu; Davé, Rajesh N; Bilgili, Ecevit

    2016-04-01

    As a drug-sparing approach in early development, vibratory milling has been used for the preparation of nanosuspensions of poorly water-soluble drugs. The aim of this study was to intensify this process through a systematic increase in vibration intensity and bead loading with the optimal bead size for faster production. Griseofulvin, a poorly water-soluble drug, was wet-milled using yttrium-stabilized zirconia beads with sizes ranging from 50 to 1500 μm at low power density (0.87 W/g). Then, this process was intensified with the optimal bead size by sequentially increasing vibration intensity and bead loading. Additional experiments with several bead sizes were performed at high power density (16 W/g), and the results were compared to those from wet stirred media milling. Laser diffraction, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, and dissolution tests were used for characterization. Results for the low power density indicated 800 μm as the optimal bead size which led to a median size of 545 nm with more than 10% of the drug particles greater than 1.8 μm albeit the fastest breakage. An increase in either vibration intensity or bead loading resulted in faster breakage. The most intensified process led to 90% of the particles being smaller than 300 nm. At the high power intensity, 400 μm beads were optimal, which enhanced griseofulvin dissolution significantly and signified the importance of bead size in view of the power density. Only the optimally intensified vibratory milling led to a comparable nanosuspension to that prepared by the stirred media milling. PMID:26182907

  10. 32 CFR 516.19 - Injunctive relief.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY AID OF CIVIL AUTHORITIES AND PUBLIC RELATIONS LITIGATION Reporting Legal Proceedings to HQDA § 516.19 Injunctive relief. (a) General. Plaintiffs... relief is granted. (4) The public interest....

  11. 32 CFR 516.19 - Injunctive relief.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY AID OF CIVIL AUTHORITIES AND PUBLIC RELATIONS LITIGATION Reporting Legal Proceedings to HQDA § 516.19 Injunctive relief. (a) General. Plaintiffs... relief is granted. (4) The public interest....

  12. 7 CFR 636.20 - Equitable relief.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., the participant may request equitable relief under 7 CFR 635.3. (b) If, during the term of a WHIP cost... provision, the participant may be eligible for equitable relief under 7 CFR 635.4. ... AGRICULTURE LONG TERM CONTRACTING WILDLIFE HABITAT INCENTIVES PROGRAM § 636.20 Equitable relief. (a) If...

  13. Southern Alaska Coastal Relief Model

    NASA Astrophysics Data System (ADS)

    Lim, E.; Eakins, B.; Wigley, R.

    2009-12-01

    The National Geophysical Data Center (NGDC), an office of the National Oceanic and Atmospheric Administration (NOAA), in conjunction with the Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado at Boulder, has developed a 24 arc-second integrated bathymetric-topographic digital elevation model of Southern Alaska. This Coastal Relief Model (CRM) was generated from diverse digital datasets that were obtained from NGDC, the United States Geological Survey, and other U.S. and international agencies. The CRM spans 170° to 230° E and 48.5° to 66.5° N, including the Gulf of Alaska, Bering Sea, Aleutian Islands, and Alaska’s largest communities: Anchorage, Fairbanks, and Juneau. The CRM provides a framework for enabling scientists to refine tsunami propagation and ocean circulation modeling through increased resolution of geomorphologic features. It may also be useful for benthic habitat research, weather forecasting, and environmental stewardship. Shaded-relief image of the Southern Alaska Coastal Relief Model.

  14. Ground control by means of cutting relief slots

    NASA Astrophysics Data System (ADS)

    Lavrikov, S. V.

    2015-10-01

    The article gives formulation and solution of a problem on stresses and strains in a rock mass around an underground excavation with a specifically preset spiral slip surface (relief slot). The contact conditions include dry friction and cohesion. It is shown that with the contact friction, the load is more uniformly distributed in rocks around the excavation. At certain values of the parameters, it is possible to enhance load-bearing capacity of rocks three times.

  15. Electroglottographic parameterization of the effects of gender, vowel and phonatory registers on vocal fold vibratory patterns: an Indian perspective.

    PubMed

    Paul, Nilanjan; Kumar, Suman; Chatterjee, Indranil; Mukherjee, Biswarup

    2011-01-01

    In-depth study on laryngeal biomechanics and vocal fold vibratory patterns reveal that a single vibratory cycle can be divided into two major phases, the closed and open phase, which is subdivided into opening and closing phases. Studies reveal that the relative time course of abduction and adduction, which in turn is dependent on the relative relaxing and tensing of the vocal fold cover and body, to be the determining factor in production of a particular vocal register like the modal (or chest), falsetto, glottal fry registers. Studies further point out Electroglottography to be particularly suitable for the study of vocal vibratory patterns during register changes. However, to date, there has been limited study on quantitative parameterization of EGG wave form in vocal fry register. Moreover, contradictory findings abound in literature regarding effects of gender and vowel types on vocal vibratory patterns, especially during phonation at different registers. The present study endeavors to find out the effects of vowel and gender differences on the vocal fold vibratory patterns in different registers and how these would be reflected in standard EGG parameters of Contact Quotient (CQ) and Contact Index (CI), taking into consideration the Indian sociolinguistic context. Electroglottographic recordings of 10 young adults (5 males and 5 females) were taken while the subjects phonated the three vowels /a/,/i/,/u/ each in two vocal registers, modal and vocal fry. Obtained raw EGG were further normalized using the Derived EGG algorithm and theCQ and CI values were derived. Obtained data were subject to statistical analysis using the 3-way ANOVA with gender, vowel and vocal register as the three variables. Post-hoc Dunnett C multiple comparison analysis were also performed. Results reveal that CQ values are significantly higher in vocal fry than modal phonation for both males and females, indicating a relatively hyperconstricted vocal system during vocal fry. The males

  16. Sampling of Stochastic Input Parameters for Rockfall Calculations and for Structural Response Calculations Under Vibratory Ground Motion

    SciTech Connect

    M. Gross

    2004-09-01

    The purpose of this scientific analysis is to define the sampled values of stochastic (random) input parameters for (1) rockfall calculations in the lithophysal and nonlithophysal zones under vibratory ground motions, and (2) structural response calculations for the drip shield and waste package under vibratory ground motions. This analysis supplies: (1) Sampled values of ground motion time history and synthetic fracture pattern for analysis of rockfall in emplacement drifts in nonlithophysal rock (Section 6.3 of ''Drift Degradation Analysis'', BSC 2004 [DIRS 166107]); (2) Sampled values of ground motion time history and rock mechanical properties category for analysis of rockfall in emplacement drifts in lithophysal rock (Section 6.4 of ''Drift Degradation Analysis'', BSC 2004 [DIRS 166107]); (3) Sampled values of ground motion time history and metal to metal and metal to rock friction coefficient for analysis of waste package and drip shield damage to vibratory motion in ''Structural Calculations of Waste Package Exposed to Vibratory Ground Motion'' (BSC 2004 [DIRS 167083]) and in ''Structural Calculations of Drip Shield Exposed to Vibratory Ground Motion'' (BSC 2003 [DIRS 163425]). The sampled values are indices representing the number of ground motion time histories, number of fracture patterns and rock mass properties categories. These indices are translated into actual values within the respective analysis and model reports or calculations. This report identifies the uncertain parameters and documents the sampled values for these parameters. The sampled values are determined by GoldSim V6.04.007 [DIRS 151202] calculations using appropriate distribution types and parameter ranges. No software development or model development was required for these calculations. The calculation of the sampled values allows parameter uncertainty to be incorporated into the rockfall and structural response calculations that support development of the seismic scenario for the

  17. Human response to vibration stress in Japanese workers: lessons from our 35-year studies A narrative review

    PubMed Central

    MATOBA, Tsunetaka

    2015-01-01

    The occupational uses with vibratory tools or vehicles provoked health disorders of users. We reviewed narratively our articles of 35 yr studies and their related literatures, and considered the pathophysiology of the hand-arm vibration disorders. Concerning the risk factors of health impairments in workers with vibratory tools, there are two conflicting schools of the researchers: The peripheral school emphasizes that vibration only makes predominant impairments on hands and arms, showing typically Raynaud’s phenomenon in the fingers. In the systemic school, the health disorders are produced by combination with vibration, noise and working environment, namely vibratory work itself, leading to diversified symptoms and signs in relation to systemic impairments. Our 35 yr studies have evidently supported the systemic school, including disorders of the central and autonomic nervous systems. The genesis is vibratory work itself, including vibration, noise, cold working environment, ergonomic and biodynamic conditions, and emotional stress in work. Because the health disorders yield in the whole body, the following measures would contribute to the prevention of health impairments: the attenuation of vibration and noise generated form vibratory machines and the regulations on operating tool hours. In conclusion, this occupational disease results from systemic impairments due to long-term occupational work with vibratory tools. PMID:26460379

  18. Human response to vibration stress in Japanese workers: lessons from our 35-year studies A narrative review.

    PubMed

    Matoba, Tsunetaka

    2015-01-01

    The occupational uses with vibratory tools or vehicles provoked health disorders of users. We reviewed narratively our articles of 35 yr studies and their related literatures, and considered the pathophysiology of the hand-arm vibration disorders. Concerning the risk factors of health impairments in workers with vibratory tools, there are two conflicting schools of the researchers: The peripheral school emphasizes that vibration only makes predominant impairments on hands and arms, showing typically Raynaud's phenomenon in the fingers. In the systemic school, the health disorders are produced by combination with vibration, noise and working environment, namely vibratory work itself, leading to diversified symptoms and signs in relation to systemic impairments. Our 35 yr studies have evidently supported the systemic school, including disorders of the central and autonomic nervous systems. The genesis is vibratory work itself, including vibration, noise, cold working environment, ergonomic and biodynamic conditions, and emotional stress in work. Because the health disorders yield in the whole body, the following measures would contribute to the prevention of health impairments: the attenuation of vibration and noise generated form vibratory machines and the regulations on operating tool hours. In conclusion, this occupational disease results from systemic impairments due to long-term occupational work with vibratory tools. PMID:26460379

  19. Characterizing the Effective Bandwidth of Nonlinear Vibratory Energy Harvesters Possessing Multiple Stable Equilibria

    NASA Astrophysics Data System (ADS)

    Panyam Mohan Ram, Meghashyam

    In the last few years, advances in micro-fabrication technologies have lead to the development of low-power electronic devices spanning critical fields related to sensing, data transmission, and medical implants. Unfortunately, effective utilization of these devices is currently hindered by their reliance on batteries. In many of these applications, batteries may not be a viable choice as they have a fixed storage capacity and need to be constantly replaced or recharged. In light of such challenges, several novel concepts for micro-power generation have been recently introduced to harness, otherwise, wasted ambient energy from the environment and maintain these low-power devices. Vibratory energy harvesting is one such concept which has received significant attention in recent years. While linear vibratory energy harvesters have been well studied in the literature and their performance metrics have been established, recent research has focused on deliberate introduction of stiffness nonlinearities into the design of these devices. It has been shown that, nonlinear energy harvesters have a wider steady-state frequency bandwidth as compared to their linear counterparts, leading to the premise that they can used to improve performance, and decrease sensitivity to variations in the design and excitation parameters. This dissertation aims to investigate this premise by developing an analytical framework to study the influence of stiffness nonlinearities on the performance and effective bandwidth of nonlinear vibratory energy harvesters. To achieve this goal, the dissertation is divided into three parts. The first part investigates the performance of bi-stable energy harvesters possessing a symmetric quartic potential energy function under harmonic excitations and carries out a detailed analysis to define their effective frequency bandwidth. The second part investigates the relative performance of mono- and bi-stable energy harvesters under optimal electric loading

  20. Finite Element Method Simulation of Double-T Type Vibrators for Flatly Supported Piezoelectric Vibratory Gyro-Sensor

    NASA Astrophysics Data System (ADS)

    Kikuchi, Takayuki; Tomikawa, Yoshiro; Soma, Takao

    2001-05-01

    In this study we deal with a flexural vibrating resonator for flatly supported vibratory gyro-sensors in parallel with the rotating plane. This type of gyro-sensor uses two vibration modes in only one plane of single crystal quartz, and therefore can be constructed to be very stable under operating conditions. The double-T type vibrator that has two T-type resonating arms and two resonant arms is designed for improving the quality factor Q of both driving and detecting vibration modes for this vibratory gyro-sensor. The result of finite element analysis of the double-T type vibrators shows the small influence of its vibration mode with the support at the center of gravity of the vibrator.

  1. Perception of frequency, amplitude, and azimuth of a vibratory dipole source by the octavolateralis system of goldfish (Carassius auratus).

    PubMed

    Dailey, Deena D; Braun, Christopher B

    2011-08-01

    Goldfish (Carassius auratus) were conditioned to suppress respiration to a 40-Hz vibratory source and subsequently tested for stimulus generalization to frequency, stimulus amplitude, and position (azimuth). Animals completely failed to generalize to frequencies separated by octave intervals both lesser and greater than the CS. However, they did appear to generalize weakly to an aerial loudspeaker stimulus of the same frequency (40 Hz) after conditioning with an underwater vibratory source. Animals had a gradually decreasing amount of generalization to amplitude changes, suggesting a perceptual dimension of loudness. Animals generalized largely or completely to the same underwater source presented at a range of source azimuths. When these azimuths were presented at a transect of 3 cm, some animals did show decrements in generalization, while others did not. This suggests that although azimuth may be perceived more saliently at distances closer to a dipole source, perception of position is not immediately salient in conditioned vibratory source detection. Differential responding to test stimuli located toward the head or tail suggests the presence of perceptual differences between sources that are rostral or caudal with respect to the position of the animal or perhaps the head. PMID:21574689

  2. The effects of goshajinkigan, a herbal medicine, on subjective symptoms and vibratory threshold in patients with diabetic neuropathy.

    PubMed

    Tawata, M; Kurihara, A; Nitta, K; Iwase, E; Gan, N; Onaya, T

    1994-12-16

    Goshajinkigan, a herbal medicine, has long been used in Japan to alleviate the subjective symptoms of diabetic neuropathy; however, its effects have not been confirmed objectively. We evaluated its effects on subjective symptoms and on vibration sensation in patients with diabetic neuropathy. The oral administration of 7.5 g/day of Goshajinkigan for 3 months (treatment period) relieved subjective symptoms of numbness in 9 of 13 patients. When the drug was discontinued for 2 months as a washout period, the subjective symptom worsened in 7 of 13 patients. Chi-square analysis revealed significant effects of Goshajiniagan on subjective symptoms (P < 0.001 for numbness and P < 0.05 for cold sensation). Vibration sensation was evaluated by measuring vibratory threshold using an SMV-5 vibrometer. There were significant changes in vibratory thresholds by paired t-test (P < 0.05) both in the upper and the lower extremities during the treatment and washout periods. Chi-square analysis also revealed a significant effect of Goshajinkigan on vibratory threshold (P < 0.01). There was no significant change in glycosylated hemoglobin as a whole during the study. These observations confirm that Goshajinkigan relieves subjective symptoms and demonstrate that it improves vibration sensation in patients with diabetic neuropathy. PMID:7705193

  3. Vibratory response of a mirror support/positioning system for the Advanced Photon Source project at Argonne National Laboratory

    SciTech Connect

    Basdogan, I.; Shu, Deming; Kuzay, T.M.; Royston, T.J.; Shabana, A.A.

    1996-08-01

    The vibratory response of a typical mirror support/positioning system used at the experimental station of the Advanced Photon Source (APS) project at Argonne National Laboratory is investigated. Positioning precision and stability are especially critical when the supported mirror directs a high-intensity beam aimed at a distant target. Stability may be compromised by low level, low frequency seismic and facility-originated vibrations traveling through the ground and/or vibrations caused by flow-structure interactions in the mirror cooling system. The example case system has five positioning degrees of freedom through the use of precision actuators and rotary and linear bearings. These linkage devices result in complex, multi-dimensional vibratory behavior that is a function of the range of positioning configurations. A rigorous multibody dynamical approach is used for the development of the system equations. Initial results of the study, including estimates of natural frequencies and mode shapes, as well as limited parametric design studies, are presented. While the results reported here are for a particular system, the developed vibratory analysis approach is applicable to the wide range of high-precision optical positioning systems encountered at the APS and at other comparable facilities.

  4. Investigating acoustic correlates of human vocal fold vibratory phase asymmetry through modeling and laryngeal high-speed videoendoscopya

    PubMed Central

    Mehta, Daryush D.; Zañartu, Matías; Quatieri, Thomas F.; Deliyski, Dimitar D.; Hillman, Robert E.

    2011-01-01

    Vocal fold vibratory asymmetry is often associated with inefficient sound production through its impact on source spectral tilt. This association is investigated in both a computational voice production model and a group of 47 human subjects. The model provides indirect control over the degree of left–right phase asymmetry within a nonlinear source–filter framework, and high-speed videoendoscopy provides in vivo measures of vocal fold vibratory asymmetry. Source spectral tilt measures are estimated from the inverse-filtered spectrum of the simulated and recorded radiated acoustic pressure. As expected, model simulations indicate that increasing left–right phase asymmetry induces steeper spectral tilt. Subject data, however, reveal that none of the vibratory asymmetry measures correlates with spectral tilt measures. Probing further into physiological correlates of spectral tilt that might be affected by asymmetry, the glottal area waveform is parameterized to obtain measures of the open phase (open/plateau quotient) and closing phase (speed/closing quotient). Subjects’ left–right phase asymmetry exhibits low, but statistically significant, correlations with speed quotient (r = 0.45) and closing quotient (r = −0.39). Results call for future studies into the effect of asymmetric vocal fold vibration on glottal airflow and the associated impact on voice source spectral properties and vocal efficiency. PMID:22225054

  5. Pressure relief subsystem design description

    SciTech Connect

    1986-07-01

    The primary function of the Pressure Relief Subsystem, a subsystem of the Vessel System, is to provide overpressure protection to the Vessel System. When the overpressure setpoint is reached, pressure is reduced by permitting the flow of primary coolant out of the Vessel System. This subsystem also provides the flow path by which purified helium is returned to the vessel system, either as circulating purge/flow from the Helium Purification Subsystem or make-up helium from the Helium Storage and Transfer Subsystem.

  6. Stochastic parameter estimation in nonlinear time-delayed vibratory systems with distributed delay

    NASA Astrophysics Data System (ADS)

    Torkamani, Shahab; Butcher, Eric A.

    2013-07-01

    The stochastic estimation of parameters and states in linear and nonlinear time-delayed vibratory systems with distributed delay is explored. The approach consists of first employing a continuous time approximation to approximate the delayed integro-differential system with a large set of ordinary differential equations having stochastic excitations. Then the problem of state and parameter estimation in the resulting stochastic ordinary differential system is represented as an optimal filtering problem using a state augmentation technique. By adapting the extended Kalman-Bucy filter to the augmented filtering problem, the unknown parameters of the time-delayed system are estimated from noise-corrupted, possibly incomplete measurements of the states. Similarly, the upper bound of the distributed delay can also be estimated by the proposed technique. As an illustrative example to a practical problem in vibrations, the parameter, delay upper bound, and state estimation from noise-corrupted measurements in a distributed force model widely used for modeling machine tool vibrations in the turning operation is investigated.

  7. Two Novel Measurements for the Drive-Mode Resonant Frequency of a Micromachined Vibratory Gyroscope

    PubMed Central

    Wang, Ancheng; Hu, Xiaoping; Luo, Bing; Jiang, Mingming; He, Xiaofeng; Tang, Kanghua

    2013-01-01

    To investigate the drive-mode resonance frequency of a micromachined vibratory gyroscope (MVG), one needs to measure it accurately and efficiently. The conventional approach to measure the resonant frequency is by performing a sweep frequency test and spectrum analysis. The method is time-consuming and inconvenient because of the requirements of many test points, a lot of data storage and off-line analyses. In this paper, we propose two novel measurement methods, the search method and track method, respectively. The former is based on the magnitude-frequency characteristics of the drive mode, utilizing a one-dimensional search technique. The latter is based on the phase-frequency characteristics, applying a feedback control loop. Their performances in precision, noise resistivity and efficiency are analyzed through detailed simulations. A test system is implemented based on a field programmable gate array (FPGA) and experiments are carried out. By comparing with the common approach, feasibility and superiorities of the proposed methods are validated. In particular, significant efficiency improvements are achieved whereby the conventional frequency method consumes nearly 5,000 s to finish a measurement, while only 5 s is needed for the track method and 1 s for the search method. PMID:24256977

  8. Programmable Mechanobioreactor for Exploration of the Effects of Periodic Vibratory Stimulus on Mesenchymal Stem Cell Differentiation

    PubMed Central

    Cashion, Avery T.; Caballero, Montserrat; Halevi, Alexandra; Pappa, Andrew; Dennis, Robert G.

    2014-01-01

    Abstract A programmable bioreactor using a voice-coil actuator was developed to enable research on the effects of periodic vibratory stimulus on human and porcine mesenchymal stem cells (MSCs). We hypothesized that low frequency vibrations would result in a cartilage phenotype and higher frequency vibrations would result in a bone phenotype. The mechanical stimulation protocol is adjusted from a computer external to the incubator via a USB cable. Once programmed, the embedded microprocessor and sensor system on the bioreactor execute the protocol independent of the computer. In each test, a sinusoidal stimulus was applied to a culture plate in 1-min intervals with a 15-min rest following each, for a total of 15 h per day for 10 days. Frequencies of 1 and 100 Hz were applied to cultures of both human and porcine umbilical cord–derived MSCs. Chondrogenesis was determined by Alcian blue staining for glycosaminoglycans and an increased differentiation index (ratio of mRNA for collagen II and collagen I). Osteogenic differentiation was indicated with Alizarin red for calcium staining and increased bone morphogenetic protein 2 mRNA. One-hertz stimulation resulted in a cartilage phenotype for both human and porcine MSCs, while 100-Hz stimulation resulted in a bone phenotype. PMID:24570842

  9. Electrophysiological responses to vibratory stimulation in the brainstem of the tadpole

    NASA Astrophysics Data System (ADS)

    Simmons, Andrea M.; Two, Aimee; Horowitz, Seth S.

    2005-04-01

    Maturation of saccular responses to vibratory stimuli in 3 axes was measured in the Rana catesbeiana tadpole across metamorphic development. The animal was suspended in a water-filled circular aluminum dish attached to a shaker table system consisting of 5 vibration exciters producing sinusoidal, translational movements in the x, y, and z planes. Multi-unit responses were recorded from the medulla with tungsten or platinum-iridium microelectrodes. Recording sites were electrolytically marked to verify electrode placement. Data were collected from 16 animals in late larval stages, before onset of metamorphic climax. Most recording sites were sensitive to vibrations in the z (vertical) direction, indicating a saccular origin of the response. Vibration frequencies of 40 Hz or below produced the strongest activity, with thresholds below a displacement of 10 nm. Secondary sensitivity was sometimes observed to either x (body-longitudinal) or y (body-lateral) directions of movement. Although some sites produced strong phase-locked activity to the stimulation, others showed more diverse temporal patterns of response. Active recording sites were found in the medial vestibular nucleus, lateral vestibular nucleus, reticular gray, and dorsal superior olivary nucleus. These data suggest that tadpole saccule is functional early in larval development, with sensitivity similar to that observed in adult bullfrogs.

  10. Design of vibratory energy harvesters under stochastic parametric uncertainty: a new optimization philosophy

    NASA Astrophysics Data System (ADS)

    Haji Hosseinloo, Ashkan; Turitsyn, Konstantin

    2016-05-01

    Vibratory energy harvesters as potential replacements for conventional batteries are not as robust as batteries. Their performance can drastically deteriorate in the presence of uncertainty in their parameters. Parametric uncertainty is inevitable with any physical device mainly due to manufacturing tolerances, defects, and environmental effects such as temperature and humidity. Hence, uncertainty propagation analysis and optimization under uncertainty seem indispensable with any energy harvester design. Here we propose a new modeling philosophy for optimization under uncertainty; optimization for the worst-case scenario (minimum power) rather than for the ensemble expectation of the power. The proposed optimization philosophy is practically very useful when there is a minimum requirement on the harvested power. We formulate the problems of uncertainty propagation and optimization under uncertainty in a generic and architecture-independent fashion, and then apply them to a single-degree-of-freedom linear piezoelectric energy harvester with uncertainty in its different parameters. The simulation results show that there is a significant improvement in the worst-case power of the designed harvester compared to that of a naively optimized (deterministically optimized) harvester. For instance, for a 10% uncertainty in the natural frequency of the harvester (in terms of its standard deviation) this improvement is about 570%.

  11. Optimization of partial-state feedback for vibratory energy harvesters subjected to broadband stochastic disturbances

    NASA Astrophysics Data System (ADS)

    Cassidy, Ian L.; Scruggs, Jeffrey T.; Behrens, Sam

    2011-08-01

    In many applications of vibratory energy harvesting, the external disturbance is most appropriately modeled as a broadband stochastic process. Optimization of the average power generated from such disturbances is a feedback control problem, and solvable via LQG (linear-quadratic-Gaussian) control theory. Implementing the optimal feedback controller requires a power electronic drive capable of two-way power flow, which can impose dynamic relationships between the voltage and current of the transducer. Determining the optimal energy harvesting current control is accomplished by solving a nonstandard Riccati equation. In this paper we show that appropriate tuning of the passive parameters in the harvesting system results in a decoupled solution to the Riccati equation and a corresponding controller that only requires half of the states for feedback. However, even when such tuning methods are not used and the solution to the Riccati equation does not decouple, it is possible to determine the states in the feedback law that contribute the most to the average power generated by the harvester. As such, partial-state feedback gains can be optimized using a gradient descent method. Two energy harvesting examples are presented, including a single-degree-of-freedom oscillator with an electromagnetic actuator and a piezoelectric bimorph cantilever beam, to demonstrate these concepts.

  12. Robust design of a vibratory gyroscope with an unbalanced inner torsion gimbal using axiomatic design

    NASA Astrophysics Data System (ADS)

    Hwang, Kwang-Hyeon; Lee, Kwon-Hee; Park, Gyung-Jin; Lee, Byeong-Leul; Cho, Yong-Chul; Lee, Seok-Han

    2003-01-01

    Recently, there has been considerable interest in micro gyroscopes made of silicon chips. These can be applied to many microelectromechanical systems, such as devices for stabilization, general rate control, directional pointing, autopilot systems, and missile control. A decoupled vibratory gyroscope has been fabricated and tested. In this research, design improvement is obtained from numerical analyses as well as from a theoretical design point of view. The existing design is analyzed by using the axiomatic approach, which provides a general framework for design. For axiomatic design, the functional requirements (FRs) are twofold: firstly, the natural frequencies should have fixed values, and secondly the system should be robust to large tolerances. According to the independence axiom, the design parameters (DPs) are classified into the same number of groups as the FRs. Each group of DPs is separately determined according to the sequence indicated by axiomatic design. When a group of DPs should be determined to enhance robustness, the Taguchi concept is employed to maintain robust performance regardless of the tolerances. It is noted that the Taguchi method is used as a unit process in the sequence of the axiomatic design.

  13. Formulating disaster relief when needs are unknown.

    PubMed

    May, P J

    1982-01-01

    As in most cases of natural disasters, relief needs arising out of the Mount St. Helens volcanic eruptions in May 1980 were greatly overestimated. Technical, bureaucratic, and political considerations all contribute to the upward bias in such cases. The errors in early estimates of relief needs can be reduced by systematic means. But more important than obtaining good early estimates is maintaining an effective control over actual disaster relief expenditures. As it turns out, the more effective systems of control usually go hand in hand with poorer early estimates, creating a dilemma for the management for disaster relief. PMID:10257572

  14. The development of children's regret and relief.

    PubMed

    Weisberg, Daniel P; Beck, Sarah R

    2012-01-01

    Previous research found that children first experience regret at 5 years and relief at 7. In two experiments, we explored three possibilities for this lag: (1) relief genuinely develops later than regret; (2) tests of relief have previously been artefactually difficult; or (3) evidence for regret resulted from false positives. In Experiment 1 (N=162 4- to 7-year-olds) children chose one of two cards that led to winning or losing tokens. Children rated their happiness then saw a better (regret) or worse (relief) alternative. Children re-rated their happiness. Regret after winning was first experienced at 4, regret after losing and relief after winning were experienced at 5 years and relief after losing at 7 years. Experiment 2 (N=297 5- to 8-year-olds) used a similar task but manipulated children's responsibility for the outcome. Greater responsibility for the outcome resulted in a greater likelihood of an experience of regret and relief. Results support that previous tests of relief were artefactually difficult and regret and relief are experienced earlier than previously thought. PMID:22077850

  15. Shaded Relief, Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This topographic image shows the western side of the volcanically active Kamchatka Peninsula, Russia. The data are from the first C-band mapping swath of the Shuttle Radar Topography Mission (SRTM). On the left side are four rivers, which flow northwest to the Sea of Okhotsk. These rivers are, from the south to north, Tigil, Amanina, Voyampolka, and Zhilovaya. The broad, flat floodplains of the rivers are shown in blue. These rivers are important spawning grounds for salmon. In the right side of the image is the Sredinnyy Khrebet, the volcanic mountain range that makes up the 3spine2 of the peninsula. The cluster of hills to the lower right is a field of small dormant volcanoes. High resolution SRTM topographic data will be used by geologists to study how volcanoes form and understand the hazards posed by future eruptions.

    This shaded relief image was generated using topographic data from the Shuttle Radar Topography Mission. A computer-generated artificial light source illuminates the elevation data to produce a pattern of light and shadows. Slopes facing the light appear bright, while those facing away are shaded. On flatter surfaces, the pattern of light and shadows can reveal subtle features in the terrain. Colors show the elevation as measured by SRTM. Colors range from blue at the lowest elevations to white at the highest elevations. This image contains about 2300 meters (7500 feet) of total relief. Shaded relief maps are commonly used in applications such as geologic mapping and land use planning.

    The Shuttle Radar Topography Mission (SRTM), launched on February 11,2000, uses the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. The mission is designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, an additional C-band imaging antenna and

  16. A successful traffic relief program

    SciTech Connect

    Dimino, R.A.; Bezkorovainy, G.; Campbell, B.

    1987-08-01

    This article reports that in August 1986, under the direction of Mayor Raymond Flynn, the City of Boston initiated Phase I of a Traffic Relief Program (TRP). The program was an interagency effort of the Boston Transportation Department and the Boston Police Department, to provide increased enforcement of the city's traffic and parking regulations on congested roadways in downtown Boston. The TRP is a reaffirmation of the city's philosophy that major arterials' primary function is the movement of traffic during periods of heavy traffic flow. There were six objectives: to reduce vehicular travel time along travel corridors; to increase street/intersection capacity; to eliminate vehicular blockage at intersections; to eliminate double parking; to eliminate pedestrian/vehicular conflicts at intersections and thus reduce the potential number of accidents; and to provide clear regulatory and street name signage.

  17. Angular circulation speed of tablets in a vibratory tablet coating pan.

    PubMed

    Kumar, Rahul; Wassgren, Carl

    2013-03-01

    In this work, a single tablet model and a discrete element method (DEM) computer simulation are developed to obtain the angular circulation speed of tablets in a vibratory tablet coating pan for range of vibration frequencies and amplitudes. The models identify three important dimensionless parameters that influence the speed of the tablets: the dimensionless amplitude ratio (a/R), the Froude number (aω2/g), and the tablet-wall friction coefficient, where a is the peak vibration amplitude at the drum center, ω is the vibration angular frequency, R is the drum radius, and g is the acceleration due to gravity. The models predict that the angular circulation speed of tablets increases with an increase in each of these parameters. The rate of increase in the angular circulation speed is observed to decrease for larger values of a/R. The angular circulation speed reaches an asymptote beyond a tablet-wall friction coefficient value of about 0.4. Furthermore, it is found that the Froude number should be greater than one for the tablets to start circulating. The angular circulation speed increases as Froude number increases but then does not change significantly at larger values of the Froude number. Period doubling, where the motion of the bed is repeated every two cycles, occurs at a Froude number larger than five. The single tablet model, although much simpler than the DEM model, is able to predict the maximum circulation speed (the limiting case for a large value of tablet-wall friction coefficient) as well as the transition to period doubling. PMID:23325382

  18. Relative performance of a vibratory energy harvester in mono- and bi-stable potentials

    NASA Astrophysics Data System (ADS)

    Masana, Ravindra; Daqaq, Mohammed F.

    2011-11-01

    Motivated by the need for broadband vibratory energy harvesting, many research studies have recently proposed energy harvesters with nonlinear characteristics. Based on the shape of their potential function, such devices are classified as either mono- or bi-stable energy harvesters. This paper aims to investigate the relative performance of these two classes under similar excitations and electric loading conditions. To achieve this goal, an energy harvester consisting of a clamped-clamped piezoelectric beam bi-morph is considered. The shape of the harvester's potential function is altered by applying a static compressive axial load at one end of the beam. This permits operation in the mono-stable (pre-buckling) and bi-stable (post-buckling) configurations. For the purpose of performance comparison, the axial load is used to tune the harvester's oscillation frequencies around the static equilibria such that they have equal values in the mono- and bi-stable configurations. The harvester is subjected to harmonic base excitations of different magnitudes and a slowly varying frequency spanning a wide band around the tuned oscillation frequency. The output voltage measured across a purely resistive load is compared over the frequency range considered. Two cases are discussed; the first compares the performance when the bi-stable harvester has deep potential wells, while the second treats a bi-stable harvester with shallow wells. Both numerical and experimental results demonstrate the essential role that the potential shape plays in conjunction with the base acceleration to determine whether the bi-stable harvester can outperform the mono-stable one and for what range of frequencies. Results also illustrate that, for a bi-stable harvester with shallow potential wells, super-harmonic resonances can activate the inter-well dynamics even for a small base acceleration, thereby producing large voltages in the low frequency range.

  19. Transient response and stability of the AGC-PI closed-loop controlled MEMS vibratory gyroscopes

    NASA Astrophysics Data System (ADS)

    Cui, J.; Chi, X. Z.; Ding, H. T.; Lin, L. T.; Yang, Z. C.; Yan, G. Z.

    2009-12-01

    This paper presents a detailed study on the transient response and stability of the automatic gain control (AGC) with a proportion-integral (PI) controller for a MEMS vibratory gyroscope, which constructs a closed-loop control system to make the gyroscope achieve a constant amplitude vibration at its resonant frequency. The nonlinear mathematical model for the control system is established by applying the averaging and linearization method, which is evaluated through numerical simulations. The stability and convergence characteristics of the whole loop are investigated by using the phase plane method and Routh-Hurwitz criterion. The analysis provides a quantitative methodology for selecting the system parameters to approach stability and an optimal transient response. The negative impact induced by drift of the resonant frequency and Q-factor is also discussed. Simulation results predicted by the model are shown to be in close agreement with the experimental results carried out on a doubly decoupled bulk micromachined gyroscope. By optimizing the control parameters, the measured rising time is less than 100 ms without obvious overshoot. The setting time of the whole loop is less than 200 ms with the relative fluctuation of velocity amplitude within approximately 16 ppm for an hour. The resulting overall performance of the gyroscope is tested under atmospheric pressure. The resonant frequencies and the Q-factor of the drive mode and sense mode are 2.986 kHz, 213 and 3.199 kHz, 233, respectively. The gyroscope achieves a scale factor of 27.6 mV/deg/s with nonlinearity less than 120 ppm in the full-scale range of 800° s-1. The threshold of sensitivity is measured to be about 0.005° s-1 with noise equivalent angular rate evaluated to be 0.001°/s/Hz1/2.

  20. Analysis of inservice inspection relief requests

    SciTech Connect

    Aldrich, D.A.; Cook, J.F.

    1989-08-01

    Nuclear Regulatory Commission (NRC) regulations require inspection (ISI) of boiling or pressurized water-cooled nuclear power plants be performed in accordance with a referenced edition and addenda of Section XI, ``Rules for Inservice Inspection of Nuclear Power Plant components,`` of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code. The regulations permit licensees to request relief from the NRC from specific ASME Code requirements that are determined to be impractical for the specific licensee. The NRC evaluates these requests and may grant such relief, but the NRC may also impose alternative or augmented inspections to assure structural reliability. The purpose,of this task was to evaluate the basis for ISI nondestructive examination (NDE) relief requests and to evaluate the effect of proposed ASME Code changes that would reduce the need for such requests or provide for more complete information in relief requests. This report contains the results of an analysis of an ISI relief request data base that has been expanded to include 1195 ISI relief requests versus the 296 relief requests covered in the first report in April 1987, EGG-SD-7430. Also relief requests were added to the data base which came from both first and second 10-year inspection intervals for several facilities. This provided the means to analyze the effect of recently approved ASME Code cases and updated Code requirements, some of which have been published as a result of earlier work on this task.

  1. 7 CFR 636.20 - Equitable relief.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... with 7 CFR part 635. Where a participant believes that detrimental reliance on the advice or action of... equitable relief under 7 CFR 635.3. The financial or technical liability for any action by a participant... that provision, the participant may be eligible for equitable relief under 7 CFR 635.4....

  2. Relief and Distress after Marital Separation.

    ERIC Educational Resources Information Center

    Spanier, Graham B.; Thompson, Linda

    1983-01-01

    Examined relief and distress as responses to the termination of marriage in a study of 205 individuals soon after their final separation. Results showed that relief is a frequent response to marital separation. Group differences in response were associated with the rewards and costs of ending a marriage. (JAC)

  3. 7 CFR 1465.33 - Equitable relief.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... participant may be eligible for equitable relief under 7 CFR part 635, section 635.3. The financial or... be eligible for equitable relief under 7 CFR part 635, section 635.4. ... payment. (b) If a participant has been found in violation of a provision of the AMA contract or...

  4. 7 CFR 636.20 - Equitable relief.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... with 7 CFR part 635. Where a participant believes that detrimental reliance on the advice or action of... equitable relief under 7 CFR 635.3. The financial or technical liability for any action by a participant... that provision, the participant may be eligible for equitable relief under 7 CFR 635.4....

  5. 7 CFR 636.20 - Equitable relief.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... with 7 CFR part 635. Where a participant believes that detrimental reliance on the advice or action of... equitable relief under 7 CFR 635.3. The financial or technical liability for any action by a participant... that provision, the participant may be eligible for equitable relief under 7 CFR 635.4....

  6. 7 CFR 636.20 - Equitable relief.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... with 7 CFR part 635. Where a participant believes that detrimental reliance on the advice or action of... equitable relief under 7 CFR 635.3. The financial or technical liability for any action by a participant... that provision, the participant may be eligible for equitable relief under 7 CFR 635.4....

  7. Aspirator increases relief valve poppet stroke

    NASA Technical Reports Server (NTRS)

    Biddle, M. E.

    1967-01-01

    Addition of an aspirator to a relief valve increases the valve poppet stroke under dynamic flow conditions. The aspirator allows poppet inlet dynamic forces to overcome relief valve spring force. It reduces the fluid pressure in the skirt cavity by providing a low pressure sense probe.

  8. Inexpensive tamper proof safety relief valve

    NASA Technical Reports Server (NTRS)

    Frankewich, P. A.

    1970-01-01

    Basic relief valve has added safety relief valve capability that relieves overpressure before failure can occur. It may be installed in inaccesible areas with a high degree of reliability, constructed from a variety of materials, and adapted to the user's specific application.

  9. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Spring loaded pressure relief valve. 64.59 Section 64.59... AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59 Spring loaded pressure relief valve. A spring loaded pressure relief valve must— (a) Be set at a...

  10. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Spring loaded pressure relief valve. 64.59 Section 64.59... AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59 Spring loaded pressure relief valve. A spring loaded pressure relief valve must— (a) Be set at a...

  11. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Spring loaded pressure relief valve. 64.59 Section 64.59... AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59 Spring loaded pressure relief valve. A spring loaded pressure relief valve must— (a) Be set at a...

  12. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Spring loaded pressure relief valve. 64.59 Section 64.59... AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59 Spring loaded pressure relief valve. A spring loaded pressure relief valve must— (a) Be set at a...

  13. 46 CFR 64.71 - Marking of pressure relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Marking of pressure relief devices. 64.71 Section 64.71... AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.71 Marking of pressure relief devices. A pressure relief device must be plainly and permanently marked with...

  14. 46 CFR 64.57 - Acceptance of pressure relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Acceptance of pressure relief devices. 64.57 Section 64... PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.57 Acceptance of pressure relief devices. A pressure relief device for an MPT must be— (a) From...

  15. Relief device for a vacuum vessel

    DOEpatents

    Fast, R.W.

    1987-04-28

    A pressure relief device for a vessel having redundant pressure relief capabilities is disclosed. An annular plate overlies a surface which has an aperture to the vessel. A seal is formed between the surface and annular plate. A solid plate overlies the annular plate. A seal is formed between the solid plate and annular plate. The relief device will open at a first predetermined pressure by lifting the solid plate. In the event the seal between solid plate and annular plate should stick the relief device will open at a second slightly higher, predetermined pressure by lifting the annular plate and solid plate together. Hinging means are provided to reclose the pressure relief device when conditions return to normal. 2 figs.

  16. Relief device for a vacuum vessel

    DOEpatents

    Fast, Ronald W.

    1987-04-28

    A pressure relief device 5 for a vessel having redundant pressure relief capabilities. An annular plate 12 overlies a surface 11 which has an aperature to the vessel. A seal is formed between the surface 11 and annular plate 12. A solid plate 13 overlies the annular plate 12. A seal is formed between the solid plate 13 and annular plate 12. The relief device 5 will open at a first predetermined pressure by lifting the solid plate 13. In the event the seal between solid plate 13 and annular plate 12 should stick the relief device 5 will open at a second slightly higher, predetermined pressure by lifting the annular plate 12 and solid plate 13 together. Hinging means 6 are provided to reclose the pressure relief device 5 when conditions return to normal.

  17. RTLS entry load relief parameter optimization

    NASA Technical Reports Server (NTRS)

    Crull, T. J.

    1975-01-01

    The results are presented of a study of a candidate load relief control law for use during the pullup phase of Return-to-Launch-Site (RTLS) abort entries. The control law parameters and cycle time which optimized performance of the normal load factor limiting phase (load relief phase) of an RTLS entry are examined. A set of control law gains, a smoothing parameter, and a normal force coefficient curve fit are established which resulted in good load relief performance considering the possible aerodynamic coefficient uncertainties defined. Also, the examination of various guidance cycle times revealed improved load relief performance with decreasing cycle time. A .5 second cycle provided smooth and adequate load relief in the presence of all the aerodynamic uncertainties examined.

  18. Stress.

    PubMed

    Chambers, David W

    2008-01-01

    We all experience stress as a regular, and sometimes damaging and sometimes useful, part of our daily lives. In our normal ups and downs, we have our share of exhaustion, despondency, and outrage--matched with their corresponding positive moods. But burnout and workaholism are different. They are chronic, dysfunctional, self-reinforcing, life-shortening habits. Dentists, nurses, teachers, ministers, social workers, and entertainers are especially susceptible to burnout; not because they are hard-working professionals (they tend to be), but because they are caring perfectionists who share control for the success of what they do with others and perform under the scrutiny of their colleagues (they tend to). Workaholics are also trapped in self-sealing cycles, but the elements are ever-receding visions of control and using constant activity as a barrier against facing reality. This essay explores the symptoms, mechanisms, causes, and successful coping strategies for burnout and workaholism. It also takes a look at the general stress response on the physiological level and at some of the damage American society inflicts on itself. PMID:18846841

  19. OPEC reorganization could spell relief

    SciTech Connect

    Crouse, P.C.

    1987-02-01

    Last year proved to be one of carnage in the oil industry, with only the large, vertically integrated, international oil companies showing strength during the oil price collapse. Independent producers and the manufacturing/service sector watched 50% or greater reductions in income. And this year holds little prospect for significant relief during its first half, although the last half could be better if and when Opec decides to once again test its strength. An Iranian victory in the Iran/Iraq war could also cause an upward movement in price. However, price instability should be less than in 1986, as the business heads toward a consensus price via political factors. The U.S. economy again showed improvement through 1986, with moderate growth of 2.6% in Gross National Product (GNP). The ongoing expansion has lasted four years and is already 17 months longer than the average peacetime expansion. However, important energy components did not show strength, and industrial production continued at level rates for the past two years.

  20. Applying photovoltaics to disaster relief

    SciTech Connect

    Young, W. Jr.

    1996-11-01

    Hurricanes, floods, tornados, earthquakes and other disasters can happen at any time, often with little or no advance warning. They can be as destructive as Hurricane Andrew leaving several hundred-thousand people homeless or as minor as an afternoon thunderstorm knocking down local power lines to your home. Major disasters leave many people without adequate medical services, potable water, electrical service and communications. In response to a natural disaster, photovoltaic (solar electric) modules offer a source of quiet, safe, pollution-free electrical power. Photovoltaic (PV) power systems are capable of providing the electrical needs for vaccine refrigerators, microscopes, medical equipment, lighting, radios, fans, communications, traffic devices and other general electrical needs. Stand alone PV systems do not require refueling and operate for long period of time from the endless energy supplied by the sun, making them beneficial during recovery efforts. This report discusses the need for electrical power during a disaster, and the capability of PV to fill that need. Applications of PV power used during previous disaster relief efforts are also presented.

  1. Local shape of pictorial relief

    PubMed Central

    Koenderink, Jan; van Doorn, Andrea; Wagemans, Johan

    2014-01-01

    How is pictorial relief represented in visual awareness? Certainly not as a “depth map,” but perhaps as a map of local surface attitudes (Koenderink & van Doorn, 1995). Here we consider the possibility that observers might instead, or concurrently, represent local surface shape, a geometrical invariant with respect to motions. Observers judge local surface shape, in a picture of a piece of sculpture, on a five-point categorical scale. Categories are cap–ridge–saddle–rut–cup–flat, where “flat” denotes the absence of shape. We find that observers readily perform such a task, with full resolution of a shape index scale (cap–ridge–saddle–rut–cup), and with excellent self-consistency over days. There exist remarkable inter-observer differences. Over a group of 10 naive observers we find that the dispersion of judgments peaks at the saddle category. There may be a relation of this finding to the history of the topic—Alberti's (1827) omission of the saddle category in his purportedly exhaustive catalog of local surface shapes. PMID:25469225

  2. Fluctuating Wall Pressure and Vibratory Response of a Cylindrical Elastic Shell due to Confined Jet Excitations.

    NASA Astrophysics Data System (ADS)

    Ng, Kam Wing

    A theoretical and experimental study was conducted to investigate the flow-induced noise and vibration caused by confined jet flows in a cylindrical duct. Unrestricted pipe flow and flows restricted by various orifices were tested for a wide range of velocities to simulate the flow in piping systems. Wall pressure data showed that the noise levels vary with the pipe's axial location and the peak noise is located at the vicinity of the end of the jet potential core. A non-dimensional wall pressure spectrum was established for the various confined jets by the Strouhal relationship, where the length scale is the jet hydraulic diameter. This jet pressure spectrum agrees with the wall pressure spectrum of a turbulent boundary layer above a rigid plane. Correlations of wall pressure fluctuations and pipe wall acceleration signals showed that jet flows generate more deterministic features than pipe flow. The coherence functions of the wall pressure and pipe wall acceleration signals are relatively high near the exit of the jet. The high coherence is probably due to the large-scale coherent structures. An analytical model was developed to study the effect of the turbulent jet flow field on the wall pressure and vibratory motion of the duct wall. Based on flow field measurements, the blocked surface pressure was calculated using Lighthill's method, and then used to drive the fluid -filled shell. The wall pressure and pipe wall acceleration were determined by solving the coupled fluid solid interaction problem. The wall pressure was obtained by summing the blocked surface pressure and the pressure due to the wall vibration. An amplitude modulated convecting wave field was used to simulate the moving acoustic sources of the jet. The random nature of the turbulent jet was incorporated into the analytical model. Specifically, the acoustic pressure was assumed to result from hydrodynamic pressure fluctuations which are uncorrelated in the radial direction, but are correlated in

  3. Menopause: Symptom Relief and Treatments

    MedlinePlus

    ... of menopause and tips for dealing with them. Hot flashes Try to notice what triggers your hot flashes and avoid those things. Possible triggers to ... foods, alcohol, caffeine, stress, or being in a hot place. Dress in layers and remove some when ...

  4. Rain Hampers Tsunami Relief Efforts

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The cleanup and relief efforts from the recent tsunamis continue in coastal communities that were ravaged by the waves all across the Indian Ocean. Heavy rains have further complicated the matter and added to the misery in parts of eastern Sri Lanka. Between December 28, 2004, and January 5, 2005, up to 10 to 15 inches of rain may have fallen along the southeast coast of the island, and as much as 20 inches (red areas) fell just offshore. This rainfall map was created by the TRMM-based, near-real time Multi-satellite Precipitation Analysis (MPA) at the NASA Goddard Space Flight Center, which monitors rainfall over the global tropics. The map shows that many other regions around the Indian Ocean were also affected by the rains, including Malaysia and parts of Sumatra. The heaviest rains fell on December 31 and January 4. The rains were likely the result of a combination of the northeast monsoon interacting with the topography and an active phase of what is known as the Madden-Julian Oscillation (MJO) (or 30-60 day oscillation). The MJO is a large-scale disturbance that propagates eastward from the Indian Ocean into the West Pacific Ocean, bringing extended periods of unsettled weather with it. Individual convective complexes within the MJO can last on the order of a day. TRMM is a joint mission between NASA and the Japanese space agency JAXA. NASA image produced by Hal Pierce (SSAI/NASA GSFC) and caption by Steve Lang (SSAI/NASA GSFC).

  5. Frequency Split Elimination Method for a Solid-State Vibratory Angular Rate Gyro with an Imperfect Axisymmetric-Shell Resonator

    PubMed Central

    Lin, Zhen; Fu, Mengyin; Deng, Zhihong; Liu, Ning; Liu, Hong

    2015-01-01

    The resonator of a solid-state vibratory gyro is responsible for sensing angular motion. Frequency splitting of an axisymmetric-shell resonator is a common problem caused by manufacturing defects. The defect causes a frequency difference between two working modes which consist of two nodes and two antinodes. The difference leads to the loss of gyroscopic effect, and thus the resonator cannot sense angular motion. In this paper, the resonator based on an axisymmetric multi-curved surface shell structure is investigated and an approach to eliminate frequency splits is proposed. Since axisymmetric multi-curved surface shell resonators are too complex to be modeled, this paper proposes a simplified model by focusing on a common property of the axisymmetric shell. The resonator with stochastic imperfections is made equivalent to a perfect shell with an imperfect mass point. Rayleigh's energy method is used in the theoretical analysis. Finite element modeling is used to demonstrate the effectiveness of the elimination approach. In real cases, a resonator's frequency split is eliminated by the proposed approach. In this paper, errors in the theoretical analysis are discussed and steps to be taken when the deviation between assumptions and the real situation is large are figured out. The resonator has good performance after processing. The elimination approach can be applied to any kind of solid-state vibratory gyro resonators with an axisymmetric shell structure. PMID:25648707

  6. Finite Element Method Simulation of Double-Ended Tuning-Fork Quartz Resonator for Application to Vibratory Gyro-Sensor

    NASA Astrophysics Data System (ADS)

    Sato, Kenji; Ono, Atsushi; Tomikawa, Yoshiro

    2003-05-01

    In the present paper, we propose a double-ended tuning-fork quartz resonator for a flatly supported vibratory gyro-sensor in parallel with its rotating plane. The resonator has the advantages of ease of miniaturization and high resistance to external shock, because the height of the proposed resonator is less than that of the conventional vertical-type tuning-fork. In addition, the proposed resonator has two end-support parts. The resonator also has the following features: (1) the vibration energy of the resonator is trapped in the driving part, therefore the resonator is only slightly affected by the support parts and (2) unwanted output signals can be removed by differential connection of the output signals from two symmetric detection electrodes. The resonator was designed using the finite element method (FEM), and its characteristics were also simulated by FEM. The obtained results show that the double-ended tuning-fork quartz resonator is applicable as a vibratory gyro-sensor, and the I/O voltage ratio of the gyro-sensor was found to be proportional to the applied angular velocity. That is, we clarified that the double-ended tuning-fork quartz resonator could be used as a gyro-sensor.

  7. Sperm retrieval in anejaculatory diabetic men who failed in drug treatment and penile vibratory stimulation during blood sugar under control.

    PubMed

    Lu, S; Cui, Y; Li, X; Zhang, H; Hu, J; Liu, J; Chen, Z-J

    2014-05-01

    Ejaculatory dysfunction is an uncommon cause of male infertility. The aim of this study was to explore non-invasive methods for sperm retrieval in anejaculatory diabetic men who failed in drug treatment and penile vibratory stimulation during blood sugar under control. Among 21 anejaculatory diabetic men who had failed in drug treatment and penile vibratory stimulation, sperm was collected by retrograde ejaculation in 10 patients (group A), and in eight patients, sperm was collected by prostatic massage (group B). We compared the outcome of subsequent assisted reproductive treatment between the two groups; the rate of fertility in group A and in group B was 78.3% and 66.6% respectively, and the rate of good embryo was 56.6% and 48.8% respectively. Eight singleton pregnancies were achieved in the 18 anejaculatory diabetic men, 5 in group A and 3 in group B, the rate of pregnancy between the two groups was 50% and 37.5% respectively. There was no significant difference in the rate of fertility, good embryo rate and pregnancy outcome between the two groups. PMID:23488950

  8. Giving the 'Green Light' to Migraine Relief

    MedlinePlus

    ... gov/medlineplus/news/fullstory_158888.html Giving the 'Green Light' to Migraine Relief Experimental light therapy finds ... headache pain, a narrow spectrum of low-intensity green light significantly reduced light sensitivity. In some cases, ...

  9. Brain Circuits Encoding Reward from Pain Relief.

    PubMed

    Navratilova, Edita; Atcherley, Christopher W; Porreca, Frank

    2015-11-01

    Relief from pain in humans is rewarding and pleasurable. Primary rewards, or reward-predictive cues, are encoded in brain reward/motivational circuits. While considerable advances have been made in our understanding of reward circuits underlying positive reinforcement, less is known about the circuits underlying the hedonic and reinforcing actions of pain relief. We review findings from electrophysiological, neuroimaging, and behavioral studies supporting the concept that the rewarding effect of pain relief requires opioid signaling in the anterior cingulate cortex (ACC), activation of midbrain dopamine neurons, and the release of dopamine in the nucleus accumbens (NAc). Understanding of circuits that govern the reward of pain relief may allow the discovery of more effective and satisfying therapies for patients with acute or chronic pain. PMID:26603560

  10. Debt relief and financing climate change action

    NASA Astrophysics Data System (ADS)

    Fenton, Adrian; Wright, Helena; Afionis, Stavros; Paavola, Jouni; Huq, Saleemul

    2014-08-01

    Slow progress in scaling-up climate finance has emerged as a major bottleneck in international negotiations. Debt relief for climate finance swaps could provide an alternative source for financing mitigation and adaptation action in developing countries.