Sample records for california bearing ratio

  1. Validation of Predicted California Bearing Ratio Values from Different Correlations

    K Shiva Prashanth Kumar


    Full Text Available In the present study different correlations were used to validate the experimental California Bearing Ratio (CBR values with predicted values proposed by different investigators. For the present study, 17 samples were collected at different intervals of sub grade soil samples from Modjo to Hawassa, in Ethiopia. From the collected samples, the basic index properties like Liquid Limit (LL, Plastic Limit (PL, Shrinkage Limit (SL, Sieve Analysis, Optimum Moisture Content (OMC and Maximum Dry Density (MDD have been evaluated in the laboratory. Finally, the experimental results are validated with the predicted results of CBR. All most all the correlations are slightly validating with the experimental results except Agarwal & Ghanekar [1], Vinod & Cletus [2] and NCHRP [3

  2. A numerical test method of California bearing ratio on graded crushed rocks using particle flow modeling

    Yingjun Jiang


    Full Text Available In order to better understand the mechanical properties of graded crushed rocks (GCRs and to optimize the relevant design, a numerical test method based on the particle flow modeling technique PFC2D is developed for the California bearing ratio (CBR test on GCRs. The effects of different testing conditions and micro-mechanical parameters used in the model on the CBR numerical results have been systematically studied. The reliability of the numerical technique is verified. The numerical results suggest that the influences of the loading rate and Poisson's ratio on the CBR numerical test results are not significant. As such, a loading rate of 1.0–3.0 mm/min, a piston diameter of 5 cm, a specimen height of 15 cm and a specimen diameter of 15 cm are adopted for the CBR numerical test. The numerical results reveal that the CBR values increase with the friction coefficient at the contact and shear modulus of the rocks, while the influence of Poisson's ratio on the CBR values is insignificant. The close agreement between the CBR numerical results and experimental results suggests that the numerical simulation of the CBR values is promising to help assess the mechanical properties of GCRs and to optimize the grading design. Besides, the numerical study can provide useful insights on the mesoscopic mechanism.

  3. Landers and Big Bear California Earthquakes, June 28, 1992

    National Oceanic and Atmospheric Administration, Department of Commerce — California residents were rudely awakened early Sunday morning June 28, 1992, by an earthquake of magnitude 7.6 (Ms) followed by a smaller 6.7 (s) magnitude...

  4. Ratio of blood serum ferritin and ferritin-bearing lymphocytes in breast cancer

    The ratio of the blood serum ferritin level and the amount of ferritin-bearing lymphocytes was determined in breast cancer patients and mastopathy patients. Direct relation between a rise of blood serum ferritin concentration, a drop in the amount of ferritin-bearing cells and tumor spreading was established in breast cancer. The maximum amount of ferritin-bearing cells was present in the blood of the patients with Stage I-IIA disease. Radical mastectomy in such patients returned the blood serum ferritin level and the amount of ferritin-bearing cells to normal

  5. Demographic characteristics and infectious diseases of a population of American black bears in Humboldt County, California.

    Stephenson, Nicole; Higley, J Mark; Sajecki, Jaime L; Chomel, Bruno B; Brown, Richard N; Foley, Janet E


    American black bears (Ursus americanus) are common, widely distributed, and broad-ranging omnivorous mammals in northern California forests. Bears may be susceptible to pathogens infecting both domestic animals and humans. Monitoring bear populations, particularly in changing ecosystems, is important to understanding ecological features that could affect bear population health and influence the likelihood that bears may cause adverse impacts on humans. In all, 321 bears were captured between May, 2001, and October, 2003, and blood samples were collected and tested for multiple zoonotic and vector-borne diseases. We found a PCR prevalence of 10% for Anaplasma phagocytophilum, and a seroprevalence of 28% for Toxoplasma gondii, 26% for Borrelia burgdorferi, 26% for A. phagocytophilum, 8% for Trichinella spiralis, 8% for Francisella tularensis and 1% for Yersinia pestis. In addition, we tested bears for pathogens of domestic dogs and found a seroprevalence of 15% for canine distemper virus and 0.6% for canine parvovirus. Our findings show that black bears can become infected with pathogens that are an important public health concern, as well as pathogens that can affect both domestic animals and other wildlife species. PMID:25700042

  6. Bear


    The famous physicist made for his scholars this riddle. A fellow encountered a bear in a wasteland. There was nobody else there. Both were frightened and ran away. Fellow to the north, bear to the west. Suddenly the fellow stopped, aimed his gun to the south and shot the bear. What colour was the bear?

  7. Bound of aspect ratio of base-isolated buildings considering nonlinear tensile behavior of rubber bearing

    Hino, J.; Yoshitomi, S.; Tsuji, M.; Takewaki, Izuru


    The purpose of this paper is to propose a simple analysis method of axial deformation of base-isolation rubber bearings in a building subjected to earthquake loading and present its applicability to the analysis of the bound of the aspect ratio of base-isolated buildings. The base shear coefficient is introduced as a key parameter for the bound analysis. The bound of the aspect ratio of base-isolated buildings is analyzed based on the relationship of the following four quantities; (i) ultimat...

  8. New observations on the Middle Fork Eel River coal-bearing beds, Mendocino County, California, USA

    Bartley, Russell H. [Mendocino County Museum, 400 East Commercial Street, Willits, CA 95490 (United States); Bartley, Sylvia E. [Noyo Hill House, 28953 Highway 20, Fort Bragg, CA 95437 (United States); Springer, David J. [College of the Redwoods-Mendocino Coast, 1211 Del Mar Drive, Fort Bragg, CA 95437 (United States); Erwin, Diane M. [Museum of Paleontology, 1101 Valley Life Sciences Building, University of California, Berkeley, CA 94720 (United States)


    Mid-19th century reports of ''immense'' coal outcrops in the Middle Fork Eel River (MFER) drainage near Round Valley in California's northern Coast Ranges fueled the early geological interest in this area, with mine development the primary focus of many studies. It was not until Samuel G. Clark's 1940 ''Geology of the Covelo District, Mendocino County, California,'' that the coal was placed in its regional geologic context and assigned to the Miocene, a determination that relied primarily on a Desmostylus hesperus molar found in shale overlying the coal and an associated equivocal, though Miocene-compatible, marine molluscan fauna. Our investigation of the MFER coal-bearing beds has provided new data from foraminifera, marine mollusks, fish remains, and the first reported fossil plants, which as a whole support Clark's Miocene age assignment. We also present an updated stratigraphy proposing under modern-day stratigraphic protocols that the informal name Sand Bank beds (SBb) be used in place of the Temblor Formation to refer to the SBb coal-bearing fluvial-marine unit. Analysis of the SBb stratigraphy and sedimentology reveals the presence of a fluvial system that flowed from a distal upland region southward toward the paleocoast of California. An abundant diverse palynoflora containing lycophytes, ferns, conifers, and mesic, thermophillic herbaceous and woody angiosperms indicates the drainage flowed through a coastal swampy forested bottomland and estuarine environment before emptying into a coastal basin. Presence of Taxodium-like wood, foliage, pollen, and other ''hydrophiles'' suggests the MFER coal was a local mire buried by the progradation of the SBb fluvial system during a regressive phase, an interpretation to be tested with future field work and detailed compositional analysis of the coal. (author)

  9. Uranium Isotopic Ratio Analysis of U-Bearing Particulates By SIMS in CIAE

    In this paper measurement method of uranium isotope ratio of uranium-bearing particles in swipe samples was introduced; Swipe sample screening program was proposed on the basis of studying various destructive assay and non-destructive assays. Scanning electron microscope(SEM) equipped with an energy dispersive X-ray fluorescence(XRF) system was applied to located the deposited uranium-containning particles on the graphite support, particle's composition and size can be identified. Some isotope ratio results were compared with those of other bulk analytical methods; By measuring the same prepared sample, we got the U-particle isotopic ratio data similar to those from IAEA NWAL, indication that our operation parameters and experimental conditions are viable and can be used for measurement of U-particle isotope ratio from swipe samples

  10. The height-width ratio limited value for rubber bearing isolated structure computed by uniform design method

    WANG Tie-ying; WANG Huan-ding; ZHANG Yong-shan; LIU Wen-guang


    Rubber isolation is the most mature control technology in practical application, and is widely used by short rigid buildings. However, many high isolation buildings have been built around the world in recent years,which do not follow the existing criterions and codes. Many researchers began to research the special problems caused by larger height-width ratio isolation structures. The overturning effect of high height-width ratio structures with rubber bearing is firstly studied. Considering the main factors, such as the height-width ratio of structures, type of site, the designed basic acceleration of ground motion and the decouple factor in horizon, computing experiment is defined with the Uniform Design Method, which is also known as designing isolation structure. The forces of the bearing under edge of structures based on the position of the rubber bearing are calculated. The result indicates that the rubber bearings will lose its functionality under very high tension and compressing force of earthquake motion in horizon and vertical, when the height-width ratio is over a certain value.Thus, based on the calculation result of isolation structures defined in the uniform design method, regression analysis is conducted, and also the rubber edge force regression formula are gotten, which has higher correlation and smaller standard deviation. This formula can be used to roughly calculate whether the pull force occurs at the edge of the building. By the edge bearings of isolation structure minimum force formula, the height-width ratio limited value of the isolation structure is deducted when rubber bearing has minimum force of zero.

  11. Effect of Different Bearing Ratios on the Friction between Ultrahigh Molecular Weight Polyethylene Ski Bases and Snow.

    Rohm, Sebastian; Knoflach, Christoph; Nachbauer, Werner; Hasler, Michael; Kaserer, Lukas; van Putten, Joost; Unterberger, Seraphin H; Lackner, Roman


    The purpose of this study was to analyze the effect of surfaces with different bearing ratios, but similar roughness heights, on the friction between ultrahigh molecular weight polyethylene (UHMWPE) and snow. On a linear tribometer positioned inside a cold chamber, the different samples were tested over a wide range of velocities and snow temperatures. The surface roughness was measured with a focus variation microscope and analyzed using the bearing ratio curve and its parameters. The surface energy was investigated by measuring the contact angles of a polar (water) and nonpolar (diiodmethane) liquid. The friction tests showed that the bearing ratio had a major effect on the friction between UHMWPE and snow. For temperatures close to the melting point a surface with wide grooves and narrow plateaus (nonbearing surface) performed well. For cold conditions, the friction was less for a surface with narrow grooves and wide plateaus (bearing surface). Interpretations of the results are given on the basis of mixed friction, with lubricated friction being dominant at higher snow temperatures and solid-solid interaction at lower ones. PMID:27115349

  12. Intake-to-delivered-energy ratios for central station and distributed electricity generation in California

    In previous work, we showed that the intake fraction (iF) for nonreactive primary air pollutants was 20 times higher in central tendency for small-scale, urban-sited distributed electricity generation (DG) sources than for large-scale, central station (CS) power plants in California [Heath, G.A., Granvold, P.W., Hoats, A.S., Nazaroff, W.W., 2006. Intake fraction assessment of the air pollutant exposure implications of a shift toward distributed electricity generation. Atmospheric Environment 40, 7164-7177]. The present paper builds on that study, exploring pollutant- and technology-specific aspects of population inhalation exposure from electricity generation. We compare California's existing CS-based system to one that is more reliant on DG units sited in urban areas. We use Gaussian plume modeling and a GIS-based exposure analysis to assess 25 existing CSs and 11 DG sources hypothetically located in the downtowns of California's most populous cities. We consider population intake of three pollutants - PM2.5, NOx and formaldehyde - directly emitted by five DG technologies - natural gas (NG)-fired turbines, NG internal combustion engines (ICE), NG microturbines, diesel ICEs, and fuel cells with on-site NG reformers. We also consider intake of these pollutants from existing CS facilities, most of which use large NG turbines, as well as from hypothetical facilities located at these same sites but meeting California's best-available control technology standards. After systematically exploring the sensitivity of iF to pollutant decay rate, the iFs for each of the three pollutants for all DG and CS cases are estimated. To efficiently compare the pollutant- and technology-specific exposure potential on an appropriate common basis, a new metric is introduced and evaluated: the intake-to-delivered-energy ratio (IDER). The IDER expresses the mass of pollutant inhaled by an exposed population owing to emissions from an electricity generation unit per quantity of electric

  13. Sulfur isotope ratios and the origins of the aerosols and cloud droplets in California stratus

    Ludwig, F. L.


    Marine aerosols often have sulfur-to-chloride ratios greater than that found in seawater. Sulfur isotope ratios (34S/32S) were measured in aerosol and cloud droplet samples collected in the San Francisco Bay Area in an attempt to understand the processes that produce the observed sulfur-to-chloride ratios. Seawater sulfur usually has very high sulfur isotope ratios; fossil fuel sulfur tends to have smaller isotope ratios and sulfur of bacteriogenic origin still smaller. Samples collected in u...

  14. Sulfur isotope ratios and the origins of the aerosols and cloud droplets in California stratus

    Marine aerosols often have sulfur-to-chloride ratios greater than that found in seawater. Sulfur isotope ratios (34S/32S) were measured in aerosol and cloud droplet samples collected in the San Francisco Bay Area in an attempt to understand the processes that produce the observed sulfur-to-chloride ratios. Seawater sulfur usually has very high sulfur isotope ratios: fossil fuel sulfur tends to have smaller isotope ratios and sulfur of bacteriogenic origin still smaller. Samples collected in unpolluted marine air over the hills south of San Francisco had sulfur ratios that were significantly lower than the values for samples collected in nearby areas that were subject to urban pollution. The highest sulfur isotope ratios were found in the offshore seawater. The results suggest bacteriogenic origins, of the marine air sulfur aerosol material. The low isotope ratios in the marine air cannot be explained as a mixture of seawater sulfur and pollutant sulfur, because both tend to have higher isotope ratios. (Auth.)

  15. Completing the Remedial Sequence and College-Level Credit-Bearing Math: Comparing Binary, Cumulative, and Continuation Ratio Logistic Regression Models

    Davidson, J. Cody


    Mathematics is the most common subject area of remedial need and the majority of remedial math students never pass a college-level credit-bearing math class. The majorities of studies that investigate this phenomenon are conducted at community colleges and use some type of regression model; however, none have used a continuation ratio model. The…

  16. Mapping CH4 : CO2 ratios in Los Angeles with CLARS-FTS from Mount Wilson, California

    K. W. Wong


    Full Text Available The Los Angeles megacity, which is home to more than 40% of the population in California, is the second largest megacity in the United States and an intense source of anthropogenic greenhouse gases (GHGs. Quantifying GHG emissions from the megacity and monitoring their spatiotemporal trends are essential to be able to understand the effectiveness of emission control policies. Here we measure carbon dioxide (CO2 and methane (CH4 across the Los Angeles megacity using a novel approach – ground-based remote sensing from a mountaintop site. A Fourier Transform Spectrometer (FTS with agile pointing optics, located on Mount Wilson at 1.67 km above sea level, measures reflected near infrared sunlight from 29 different surface targets on Mount Wilson and in the Los Angeles megacity to retrieve the slant column abundances of CO2, CH4 and other trace gases above and below Mount Wilson. This technique provides persistent space and time resolved observations of path-averaged dry-air GHG concentrations, XGHG, in the Los Angeles megacity and simulates observations from a geostationary satellite. In this study, we combined high sensitivity measurements from the FTS and the panorama from Mount Wilson to characterize anthropogenic CH4 emissions in the megacity using tracer : tracer correlations. During the period between September 2011 and October 2013, the observed XCH4 : XCO2 excess ratio, assigned to anthropogenic activities, varied from 5.4 to 7.3 ppb CH4 (ppm CO2−1, with an average of 6.4 ± 0.5 ppb CH4 (ppm CO2−1 compared to the value of 4.6 ± 0.9 ppb CH4 (ppm CO2−1 expected from the California Air Resources Board (CARB bottom-up emission inventory. Persistent elevated XCH4 : XCO2 excess ratios were observed in Pasadena and in the eastern Los Angeles megacity. Using the FTS observations on Mount Wilson and the bottom-up CO2 emission inventory, we derived a top-down CH4 emission of 0.39± 0.06 Tg CH4 year−1 in the Los Angeles megacity. This is 18

  17. Electric-field-ratio profiling at the Silsilah tin-bearing greisen deposit, Kingdom of Saudi Arabia

    Kamilli, R.J.; Zablocki, C.J.


    Buried, possibly mineralized granite cupolas at the Silsilah tin deposit in Saudi Arabia have been successfully located using a closely spaced electric-field-ratio profiling technique. In this study electrical fields at 27 and 270 Hz across grounded electrodes spaced 50m apart were measured along six traverses. The technique allowed the authors to identify and distinguish among unroofed granite cupolas, cupolas with their aplite-pegmatite apical contact zones intact, strong and weak greisens, dikes, faults, and pervasively argillized rocks. -from Authors

  18. Field evidence for fault controlled intrusion of blue-schist-bearing melange into an accretionary wedge, Island Mountain, California

    Lamons, R.


    Two lithologic units of the Franciscan are well exposed along a loop of the Eel River at Island Mountain. They are 1) zeolite or lower grade lithic graywackes, and 2) a 0.5 km wide band of black shaly melange containing blueschist, chert, greenstone, metagraywacke, and a graywacke-hosted copper deposit. Sedimentary features were not observed in the melange. The graywacke was subdivided on the basis of presence or absence of sodium-cobaltonitrate stained K-spar. Field relationships suggest that the blueschist-bearing melange was emplaced along steep NW-dipping faults in an accretionary wedge. Mapping of S. Jewett Rock and SW Lake Mountain quadrangles show narrow anastomosing bands of the melange following NW-trending faults. East of this band, graywackes without K-spar are folded along NW/SE axes. No folds were found to the west. Other Melange bands pinch out into faults which juxtapose graywackes of different facies. The sheared melange bands are not folded and shale beds in the graywacke show little shear so the melange bands are unlikely to be sheared olistostromes. The areal extent of graywacke is about ten times that of melange shales. Assuming this pattern continues laterally and at depth, the amount of ductile material in the melange is far less than that assumed by Cloos (1982) in his flow model for melange. The ductile melange may have been forced upward by metamorphically produced volatiles, or as a result of relative plate motion. It originated at depth, moved up along the top of a subducting slab, plucking clasts, then splayed upward into pre-existing faults in the accretionary wedge.

  19. A 3-Dimensional Model of Water-Bearing Sequences in the Dominguez Gap Region, Long Beach, California

    Ponti, Daniel J.; Ehman, Kenneth D.; Edwards, Brian D.; Tinsley, John C., III; Hildenbrand, Thomas; Hillhouse, John W.; Hanson, Randall T.; McDougall, Kristen; Powell, Charles L.; Wan, Elmira; Land, Michael; Mahan, Shannon; Sarna-Wojcicki, Andrei M.


    A 3-dimensional computer model of the Quaternary sequence stratigraphy in the Dominguez gap region of Long Beach, California has been developed to provide a robust chronostratigraphic framework for hydrologic and tectonic studies. The model consists of 13 layers within a 16.5 by 16.1 km (10.25 by 10 mile) square area and extends downward to an altitude of -900 meters (-2952.76 feet). Ten sequences of late Pliocene to Holocene age are identified and correlated within the model. Primary data to build the model comes from five reference core holes, extensive high-resolution seismic data obtained in San Pedro Bay, and logs from several hundred water and oil wells drilled in the region. The model is best constrained in the vicinity of the Dominguez gap seawater intrusion barrier where a dense network of subsurface data exist. The resultant stratigraphic framework and geologic structure differs significantly from what has been proposed in earlier studies. An important new discovery from this approach is the recognition of ongoing tectonic deformation throughout nearly all of Quaternary time that has impacted the geometry and character of the sequences. Anticlinal folding along a NW-SE trend, probably associated with Quaternary reactivation of the Wilmington anticline, has uplifted and thinned deposits along the fold crest, which intersects the Dominguez gap seawater barrier near Pacific Coast Highway. A W-NW trending fault system that approximately parallels the fold crest has also been identified. This fault progressively displaces all but the youngest sequences down to the north and serves as the southern termination of the classic Silverado aquifer. Uplift and erosion of fining-upward paralic sequences along the crest of the young fold has removed or thinned many of the fine-grained beds that serve to protect the underlying Silverado aquifer from seawater contaminated shallow groundwater. As a result of this process, the potential exists for vertical migration of

  20. Feather lead concentrations and207Pb/206Pb ratios reveal lead exposure history of California condors (Gymnogyps californianus)

    Finkelstein, M.E.; George, D.; Scherbinski, S.; Gwiazda, R.; Johnson, M.; Burnett, J.; Brandt, J.; Lawrey, S.; Pessier, Allan P.; Clark, M.; Wynne, J.; Grantham, And J.; Smith, D.R.


    Lead poisoning is a primary factor impeding the survival and recovery of the critically endangered California Condor (Gymnogyps californianus). However, the frequency and magnitude of lead exposure in condors is not well-known in part because most blood lead monitoring occurs biannually, and biannual blood samples capture only ???10% of a bird's annual exposure history. We investigated the use of growing feathers from free-flying condors in California to establish a bird's lead exposure history. We show that lead concentration and stable lead isotopic composition analyses of sequential feather sections and concurrently collected blood samples provided a comprehensive history of lead exposure over the 2-4 month period of feather growth. Feather analyses identified exposure events not evident from blood monitoring efforts, and by fitting an empirically derived timeline to actively growing feathers, we were able to estimate the time frame for specific lead exposure events. Our results demonstrate the utility of using sequentially sampled feathers to reconstruct lead exposure history. Since exposure risk in individuals is one determinant ?? 2010 American Chemical Society.

  1. Comparison of Oxygenate Mixing Ratios Observed in the San Joaquin Valley, California, as a Consequence of Dairy Farming

    Yang, M. M.; Blake, D. R.


    The San Joaquin Valley Air Basin in Central California is plagued with air quality problems, and is classified by the U.S. Environmental Protection Agency (EPA) as a serious non-attainment area for health-based eight-hour federal ozone (smog) standard (1). One of the main sources of Volatile Organic Compounds (VOCs), and indirect sources of ozone in the Valley, has been identified as dairy farming (2). Among these compounds, we have found that several OVOCs such as ethanol, methanol, acetone and acetaldehyde are produced in major quantities throughout the San Joaquin valley as by-products of yeast fermentation of silage and photochemical oxidation. These oxygenates, especially ethanol, play an important role in ozone (O3) formation within the valley. Since 2008, several different types of sampling protocols have been employed by our group in order to determine the degree of enhancement of the four oxygenates in the valley air shed, as well as to determine their sources, emission profiles and emission rates (2). In 2008 and 2009, samples were in early summer, allowing us to compare the difference in concentration levels between both years.The photochemical production of ozone was calculated for each of the four oxygenates and approximately one hundred other quantified VOCs. Based on the Maximum Incremental Reactivity (MIR) scale and concentrations of each oxygenate in the atmosphere, for both 2008 and 2009, as much as 15% of O3 production in the valley is from ethanol and its photochemical by-product acetaldehyde. Our findings suggest that the data observed in 2008 is consistent with that observed in 2009, with a slight decrease in concentrations overall for 2009. 1. Lindberg, J. Analysis of the San Joaquin Valley 2007 Ozone Plan. State of California Air Resources Board. Final Draft Staff Report. 5/30/2007. 2. M. Yang, S. Meinardi, C. Krauter, D.R. Blake. Characterization of VOC Emissions from Various Components of Dairy Farming and their effect on San Joaquin

  2. Ion-microprobe measurements of Mg, Ca, Ti and Fe isotopic ratios and trace element abundance in hibonite-bearing inclusions in primitive meteorites

    This thesis reports the isotopic abundances of Mg, Ca, and Ti and rare earth element (REE) abundances in 19 hibonite-bearing inclusions from primative meteorites. The isotopic ratios of Fe were measured in one of the samples, Lance HH-1. These measurements were made by means of secondary ion mass spectrometry (CAMECA IMS-3f). The novel hardware and software developments that made this work possible are described in detail. The samples were studied in thin section in order to investigate the relationship between the inclusions and their mineralogical environments. Inclusions from a number of different meteorites, specifically, Mighei, Murray, Murchison, Lance, Efremovka, Vigarano, Qingzhen, Dhajala, and Semarkona, were studied. The isotopes of Ca and Ti show large and correlated abundance anomalies in their most neutron-rich isotopes, 48Ca and 50Ti. The largest anomalies among the samples studied here are in the Murray inclusion MY-F6, with a 4.6% deficit in 48Ca and a 5.2% deficit in 50Ti, and Lance HH-1, with 3.3% and 6.0% deficits in 48Ca and 50Ti respectively. Correlated excesses of 48Ca and 50Ti, up to 2.4% and 1.4% respectively, are found in some other samples studied here. The fact that there is a correlation of isotopic anomalies in two different elements is clear evidence for a nucleosynthetic origin of these effects. Various possibilities for the origin of these isotopic anomalies are discussed and it is shown that a Cosmic Chemical Memory-like model of the incomplete mixing of dust grains from one or several supernovae is sufficient to explain the data. Magnesium isotopes show excesses of 26Mg, attributable to the in-situ decay of 26Al, in 7 of these inclusions

  3. Food habits of American black bears as a metric for direct management of humanbear conflict in Yosemite Valley, Yosemite National Park, California

    Greenleaf, S.S.; Matthews, S.M.; Wright, R.G.; Beecham, J.J.; Leithead, H.M.


    The management of human-American black bear (Ursus americanus) conflict has been of significant concern for Yosemite National Park (YNP) personnel since the 1920s. Park managers implemented the YNP Human-Bear Management Plan in 1975 in an effort to reduce human-bear conflicts, especially in the extensively developed Yosemite Valley (YV). We used scat analysis to estimate annual and seasonal food habits of black bears in YV during 2001-02. We assessed the success of efforts to reduce the availability of anthropogenic foods, including garbage, by examining changes in the diet compared to a study from 1974-78 (Graber 1981). We also quantified consumption of non-native fruit to address its possible contribution to human-bear conflicts. The annual percent volume of human-provided food and garbage in black bear scats in YV decreased from 21% to 6% between 1978 and 2002, indicating YNP efforts have been effective. We found high use of non-native apples by bears throughout YV. Non-native food sources could be contributing to habituation and food conditioning, given their proximity to developed areas of YV. We recommend that YNP managers continue to (1) adapt and improve their management tools to address changing circumstances, (2) quantify the success of new management tools, and (3) reduce the availability of non-native food sources. ?? 2009 International Association for Bear Research and Management.

  4. Intra-shell boron isotope ratios in the symbiont-bearing benthic foraminiferan Amphistegina lobifera: Implications for δ 11B vital effects and paleo-pH reconstructions

    Rollion-Bard, C.; Erez, J.


    The boron isotope composition of marine carbonates is considered to be a seawater pH proxy. Nevertheless, the use of δ 11B has some limitations such as the knowledge of the fractionation factor ( α4-3) between boric acid and the borate ion and the amplitude of "vital effects" on this proxy that are not well constrained. Using secondary ion mass spectrometry (SIMS) we have examined the internal variability of the boron isotope ratio in the shallow water, symbionts bearing foraminiferan Amphistegina lobifera. Specimens were cultured at constant temperature (24 ± 0.1 °C) in seawater with pH ranging between 7.90 and 8.45. Intra-shell boron isotopes showed large variability with an upper limit value of ≈30‰. Our results suggest that the fractionation factor α4-3 of 0.97352 ( Klochko et al., 2006) is in better agreement with our experiments and with direct pH measurements in seawater vacuoles associated with the biomineralization process in these foraminifera. Despite the large variability of the skeletal pH values in each cultured specimen, it is possible to link the lowest calculated pH values to the experimental culture pH values while the upper pH limit is slightly below 9. This variability can be interpreted as follows: foraminifera variably increase the pH at the biomineralization site to about 9. This increase above ambient seawater pH leads to a range in δ 11B (Δ 11B) for each seawater pH. This Δ 11B is linearly correlated with the culture seawater pH with a slope of -13.1 per pH unit, and is independent of the fractionation factor α4-3, or the δ 11B sw through time. It may also be independent of the p KB (the dissociation constant of boric acid) value. Therefore, Δ 11B in foraminifera can potentially reconstruct paleo-pH of seawater.

  5. A Survey of \\delta18O and \\delta15N Ratios in Ground Water from an Agricultural Community in the San Joaquin Valley, California

    Glowacki, S. D.; Suen, C. J.


    We studied ground water samples from domestic and monitoring wells in an agricultural community in the eastern side of the San Joaquin Valley, California. The study area is rich in alluvial soils creating an extremely fertile farmland. Livestock farms and agricultural fields are abundant in the area. Fifty-four ground water samples were analyzed for \\delta18O and \\delta15N in dissolved nitrate, in addition to nutrients and major minerals. Nitrate concentration levels in groundwater are elevated and affected by agricultural and other activities. Possible sources of nutrients include: a municipal waste-water treatment facility, a raisin processing plant, a meat processing plant, a turkey farm, diary operations, and agricultural fields. However, except for the turkey farm and a diary, we found no statistical significant contribution of nitrate from the other facilities as compared to the rest of the area. The \\delta18O versus \\delta15N ratios plot of dissolved ground water nitrate shows most samples clustered around an area consistent with soil organic nitrogen. In addition, the rest of the samples show a trend that is indicative of denitrification process. Generally, high \\delta15N values are associated with low nitrate concentrations. The isotopic signal of denitrification is particularly pronounced in samples in the vicinity of the waste water treatment facility, where the highest values of \\delta15N and the lowest nitrate concentrations are observed. However, these samples also have elevated chloride concentrations indicating a waste-water source. These data suggest that the denitrification in the subsurface may have been enhanced by bacteria species introduced by the effluence of the plant. [This study was performed with the collaboration of Steven R Silva of USGS, Menlo Park, and Iris Yamagata and Holly Jo Ferrin of California Department of Water Resources.

  6. Relationship between the weight-bearing ratio on the affected lower extremity and gait ability using a portable electronic foot sensor shoe (Step Aid®) in hemiplegic stroke patients

    Itotani, Keisuke; Murakami, Masahito; Itotani, Motoko; Nagai, Atsushi; Imabori, Yuzo; Fujimoto, Kazuyuki; Tanaka, Mamoru; Kato, Junichi


    [Purpose] This study investigated the association between the weight-bearing ratio (WBR) and gait ability of a paretic lower limb while walking using a shoe-type load-measuring apparatus. [Subjects] The Subjects comprised 17 stroke patients who were classified into the following two groups: the independent walking group, and the non-independent walking group. [Methods] The 10-m walking time (inside and outside parallel bars) and the Berg Balance Scale (BBS) were measured. The WBR of the paret...

  7. Near-Surface San Andreas Fault Location and Dip Near Woodside, California From Tomographic Vp, Vs, and Vp/Vs Ratios

    Goldman, M.; Catchings, R.; Sickler, R. R.; Criley, C.; Prentice, C. S.


    The slip history of the San Andreas Fault (SAF) on the San Francisco peninsula is not well determined, and paleoseismic investigations to date yield inconsistent results, possibly because previous measurements were made on differing near-surface traces of the SAF. Furthermore, ground-shaking modeling requires accurate shallow-depth S-wave velocities across the fault zone and accurate fault dips; the existing Bay Area 3-D velocity models lack such measurements. To locate all near-surface traces of the SAF within 150 m of the 1906 surface rupture, to determine near-surface shear-wave velocities (VS30 to VS100), and to determine the fault dip, the USGS acquired a set of 300-m-long, high-resolution, P- and S-wave seismic imaging profiles across the SAF near Woodside, California, centered on the 1906 surface rupture zone. Sources (seisgun and hammer) and receivers (40-Hz P-wave and 4.5-Hz S-wave) were spaced at 3-m intervals. We developed independent P- and S-wave tomographic velocity models to depths of ~ 120 m (P-waves) and 80 m (S-waves). P-wave velocities vary widely from near the surface (Vp = 800 m/s, Vs = 250) to 100 m depth (Vp > 3000 m/s, Vs > 500 m/s). The 1906 surface rupture zone forms P- and S-wave low-velocity zones (Vp = 1600 to 1800 m/s; Vs = 250 to 350 m/s) within the fault zone relative to outside the fault zone (Vp = 2000 to 2200 m/s; Vs = 300 to 400 m/s). Vp/Vs ratios range from about 2.8 to about 5.7, with higher ratios on either side of the 1906 surface rupture zone and on the uphill (southwest) side. Southwest-dipping Vp/Vs contours suggest a 60o-southwest dip for one of the fault traces. However, a CDP reflection stack shows a near-vertical dip of the main 1906 rupture zone to 1.2 km depth, and the stack shows evidence for multiple fault traces. Collectively, these new data show a complex fault structure and highly variable velocities across the fault zone, which should aid paleoseismic investigations and improve existing ground-shaking models.

  8. Journal bearing

    Menke, John R.; Boeker, Gilbert F.


    1. An improved journal bearing comprising in combination a non-rotatable cylindrical bearing member having a first bearing surface, a rotatable cylindrical bearing member having a confronting second bearing surface having a plurality of bearing elements, a source of lubricant adjacent said bearing elements for supplying lubricant thereto, each bearing element consisting of a pair of elongated relatively shallowly depressed surfaces lying in a cylindrical surface co-axial with the non-depressed surface and diverging from one another in the direction of rotation and obliquely arranged with respect to the axis of rotation of said rotatable member to cause a flow of lubricant longitudinally along said depressed surfaces from their distal ends toward their proximal ends as said bearing members are rotated relative to one another, each depressed surface subtending a radial angle of less than, and means for rotating said rotatable bearing member to cause the lubricant to flow across and along said depressed surfaces, the flow of lubricant being impeded by the non-depressed portions of said second bearing surface to cause an increase in the lubricant pressure.

  9. Accessory mineral U-Th-Pb ages and 40Ar/39Ar eruption chronology, and their bearing on rhyolitic magma evolution in the Pleistocene Coso volcanic field, California

    Simon, J.I.; Vazquez, J.A.; Renne, P.R.; Schmitt, A.K.; Bacon, C.R.; Reid, M.R.


    We determined Ar/Ar eruption ages of eight extrusions from the Pleistocene Coso volcanic field, a long-lived series of small volume rhyolitic domes in eastern California. Combined with ion-microprobe dating of crystal ages of zircon and allanite from these lavas and from granophyre geothermal well cuttings, we were able to track the range of magma-production rates over the past 650 ka at Coso. In ??? 230 ka rhyolites we find no evidence of protracted magma residence or recycled zircon (or allanite) from Pleistocene predecessors. A significant subset of zircon in the ???85 ka rhyolites yielded ages between ???100 and 200 Ma, requiring that generation of at least some rhyolites involves material from Mesozoic basement. Similar zircon xenocrysts are found in an ???200 ka granophyre. The new age constraints imply that magma evolution at Coso can occur rapidly as demonstrated by significant changes in rhyolite composition over short time intervals (???10's to 100's ka). In conjunction with radioisotopic age constraints from other young silicic volcanic fields, dating of Coso rhyolites highlights the fact that at least some (and often the more voluminous) rhyolites are produced relatively rapidly, but that many small-volume rhyolites likely represent separation from long-lived mushy magma bodies. ?? The Author(s) 2009.

  10. In situ radiation measurement and estimation of U/Th ratio to reflect on the uranium bearing potential zone in metamorphic rocks of Mahendragarh District, Haryana

    Gross gamma radiation survey was carried out using NaI(Tl) scintillator based portable gamma ray spectrometer (PGRS) around areas of Gaonri, Dholera, Pachnota and Meghot in Mahendragarh district, Haryana. Geologically the area forms part of north Delhi fold belt comprising calc-silicate, quartz biotite schist, impure marble, quartzite and pegmatite rocks. Equivalent uranium (eU3O8) concentration in ppm was estimated in situ on a regular grid pattern of 500 m (E-W) x 1000 m (N-S) and grab samples were collected at grid locations for analyzing in the laboratory for estimating the contents of eU3O8 Raeq, ThO2 and %K. A comparison with the laboratory analysed grab samples for eU3O8 data and in situ radiation measurements shows a good match of the two sets of data. The in situ measurements indicate higher concentration of eU3O8 in Chapra Bibipur in northeastern most corners, Maghot area in central part, Gaonri in western part and Pachnota in southwestern part of the study area. As index to uranium favorability, U(Raeq)/Th contour map (prepared using Surfer software with Krieging interpolation method for this grid size) based on the data on grab samples was generated which show three major clusters of relatively high U/Th ratio. The blocks delineated are enriched in sodic minerals albite which support albite hosted uranium mineralization potential in metamorphic rocks in Haryana. (author)

  11. Stable isotopes to detect food-conditioned bears and to evaluate human-bear management

    Hopkins, John B., III; Koch, Paul L.; Schwartz, Charles C.; Ferguson, Jake M.; Greenleaf, Schuyler S.; Kalinowski, Steven T.


    We used genetic and stable isotope analysis of hair from free-ranging black bears (Ursus americanus) in Yosemite National Park, California, USA to: 1) identify bears that consume human food, 2) estimate the diets of these bears, and 3) evaluate the Yosemite human–bear management program. Specifically, we analyzed the isotopic composition of hair from bears known a priori to be food-conditioned or non-food-conditioned and used these data to predict whether bears with an unknown management status were food-conditioned (FC) or non-food-conditioned (NFC). We used a stable isotope mixing model to estimate the proportional contribution of natural foods (plants and animals) versus human food in the diets of FC bears. We then used results from both analyses to evaluate proactive (population-level) and reactive (individual-level) human–bear management, and discussed new metrics to evaluate the overall human–bear management program in Yosemite. Our results indicated that 19 out of 145 (13%) unknown bears sampled from 2005 to 2007 were food-conditioned. The proportion of human food in the diets of known FC bears likely declined from 2001–2003 to 2005–2007, suggesting proactive management was successful in reducing the amount of human food available to bears. In contrast, reactive management was not successful in changing the management status of known FC bears to NFC bears, or in reducing the contribution of human food to the diets of FC bears. Nine known FC bears were recaptured on 14 occasions from 2001 to 2007; all bears were classified as FC during subsequent recaptures, and human–bear management did not reduce the amount of human food in the diets of FC bears. Based on our results, we suggest Yosemite continue implementing proactive human–bear management, reevaluate reactive management, and consider removing problem bears (those involved in repeated bear incidents) from the population.

  12. Determination of in-flight AVIRIS spectral, radiometric, spatial and signal-to-noise characteristics using atmospheric and surface measurements from the vicinity of the rare-earth-bearing carbonatite at Mountain Pass, California

    Green, Robert O.; Vane, Gregg; Conel, James E.


    An assessment of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) performance was made for a flight over Mountain Pass, California, July 30, 1987. The flight data were reduced to reflectance using an empirical algorithm which compensates for solar, atmospheric and instrument factors. AVIRIS data in conjunction with surface and atmospheric measurements acquired concurrently were used to develop an improved spectral calibration. An accurate in-flight radiometric calibration was also performed using the LOWTRAN 7 radiative transfer code together with measured surface reflectance and atmospheric optical depths. A direct comparison with coincident Thematic Mapper imagery of Mountain Pass was used to demonstrate the high spatial resolution and good geometric performance of AVIRIS. The in-flight instrument noise was independently determined with two methods which showed good agreement. A signal-to-noise ratio was calculated using data from a uniform playa. This ratio was scaled to the AVIRIS reference radiance model, which provided a basis for comparison with laboratory and other in-flight signal-to-noise determinations.

  13. Geochemical correlation and 40Ar/39Ar dating of the Kern River ash bed and related tephra layers: Implications for the stratigraphy of petroleum-bearing formations in the San Joaquin Valley, California

    Baron, D.; Negrini, R.M.; Golob, E.M.; Miller, D.; Sarna-Wojcicki, A.; Fleck, R.J.; Hacker, B.; Erendi, A.


    The Kern River ash (KRA) bed is a prominent tephra layer separating the K and G sands in the upper part of the Kern River Formation, a major petroleum-bearing formation in the southern San Joaquin Valley (SSJV) of California. The minimum age of the Kern River Formation was based on the tentative major-element correlation with the Bishop Tuff, a 0.759??0.002 Ma volcanic tephra layer erupted from the Long Valley Caldera. We report a 6.12??0.05 Ma 40Ar/39Ar date for the KRA, updated major-element correlations, trace-element correlations of the KRA and geochemically similar tephra, and a 6.0??0.2 Ma 40Ar/39Ar age for a tephra layer from the Volcano Hills/Silver Peak eruptive center in Nevada. Both major and trace-element correlations show that despite the similarity to the Bishop Tuff, the KRA correlates most closely with tephra from the Volcano Hills/Silver Peak eruptive center. This geochemical correlation is supported by the radiometric dates which are consistent with a correlation of the KRA to the Volcano Hills/Silver Peak center but not to the Bishop Tuff. The 6.12??0.05 Ma age for the KRA and the 6.0??0.2 Ma age for the tephra layer from the Volcano Hills/Silver Peak eruptive center suggest that the upper age of the Kern River Formation is over 5 Ma older than previously thought. Re-interpreted stratigraphy of the SSJV based on the new, significantly older age for the Kern River Formation opens up new opportunities for petroleum exploration in the SSJV and places better constraints on the tectonostratigraphic development of the SSJV. ?? 2007 Elsevier Ltd and INQUA.

  14. Empirical Model Evaluation of Sedimentary Residual Soil Bearing Capacity from Surface Wave Method

    Sri Atmaja Rosyidi


    Full Text Available Bearing capacity of the subgrade layers has significant influence on the performance of the overall pavement structure. In this study, the Spectral Analysis of Surface Wave (SASW method was used for assessing the stiffness of pavement subgrade layer. The SASW method employed was based on the Rayleigh-wave propagation. Using the phase difference data of Rayleigh waves, the experimental dispersion curve of phase velocity was obtained. Consequently, inversion process was conducted to obtain the shear wave velocity and the dynamic modulus of the pavement structure. The results showed that some empirical models of the shear wave velocity and the dyamic elastic modulus versus soil bearing capacity of the California bearing ratio (CBR and dynamic cone penetrometer (DCP were derived. Good agreement was also found between these empirical models compared to that of previous studies

  15. California Bioregions

    California Department of Resources — California regions developed by the Inter-agency Natural Areas Coordinating Committee (INACC) were digitized from a 1:1,200,000 California Department of Fish and...

  16. Hydrodynamic bearings

    Bonneau, Dominique; Souchet, Dominique


    This Series provides the necessary elements to the development and validation of numerical prediction models for hydrodynamic bearings. This book describes the rheological models and the equations of lubrication. It also presents the numerical approaches used to solve the above equations by finite differences, finite volumes and finite elements methods.

  17. Bearing structures

    A hydrostatic bearing for the lower end of the vertical shaft of a sodium pump comprises a support shell encircling the shaft and a bush located between the shell and shaft. Liquid sodium is fed from the pump outlet to the bush/shaft and bush/shell interfaces to provide hydrostatic support. The bush outer surface and the shell inner surface are of complementary part-spherical shape and the bush floats relative to the shaft so that the bush can align itself with the shaft axis. Monitoring of the relative rotational speed of the bush with respect to the shaft (such rotation being induced by the viscous drag forces present) is also performed for the purposes of detecting abnormal operation of the bearing or partial seizure, at least one magnet is rotatable with the bush, and a magnetic sensor provides an output having a frequency related to the speed of the bush. (author)

  18. Tooling Converts Stock Bearings To Custom Bearings

    Fleenor, E. N., Jr.


    Technique for reworking stock bearings saves time and produces helicopter-rotor bearings ground more precisely. Split tapered ring at one end of threaded bolt expands to hold inside of inner race bearing assembly; nut, at other end of bolt, adjusts amount of spring tension. Piece of hardware grasps bearing firmly without interfering with grinding operation. Operation produces bearing of higher quality than commercially available bearings.

  19. Development of Flexible Bearing



    Full Text Available Elastomeric base isolation systems are proven to be effective in reducing seismic forces transmitted to buildings. However, due to their cost, the use of these devices is currently limited to large and expensive buildings. A fiber reinforced elastomeric isolator utilizes fiber fabric, such as carbon fiber, glass fibre, and etc. as the reinforcement material instead of solid steel plates. The fibre fabric reinforcement is extensible in tension and has no flexural rigidity. Elastomers normally used in the isolator are natural rubber; neoprene, butyl rubber and nit rile rubber etc. These devices were fabricated by binding alternating layers of rubber and fibre mesh. The fibre mesh is used to increase the vertical stiffness of the bearings while maintaining low lateral stiffness. Characterizing the behaviour of a fibre reinforced bearing “shape factor” of the bearing, Poisson’s ratio of the elastomeric material and flexibility of the reinforcing sheets and investigate the effect of reinforcement flexibility on compressive behaviour of elastomeric bearings with different geometrical and material properties. Bonding with fibre reinforcements can increase the stiffness of elastic layers only when the elastic layer is compressed.

  20. 77 FR 10472 - San Bernardino National Forest, Mountaintop Ranger District, California, Mitsubishi South Quarry...


    ..., Lucerne Valley, California 92356 beginning at 7 pm PST, and Tuesday, March 20, 2012 at the Big Bear Discovery Center, 40971 North Shore Drive (Highway 38), Fawnskin, California 92333 beginning at 7 pm PST....

  1. Down-Regulation of Treg Cells and Up-Regulation of Th1/Th2 Cytokine Ratio Were Induced by Polysaccharide from Radix Glycyrrhizae in H22 Hepatocarcinoma Bearing Mice

    Xiaobing Li; Aiping Lu; Li Xu; Hongyan Zhao; Biao Liu; Xiaojuan He


    Radix Glycyrrhizae polysaccharide (GP) possesses multiple pharmacological activities. However, the effect of GP on CD4+CD25+ regulatory T (Treg) cells has not been elucidated. This study aimed to investigate the effects of GP on Treg cells and Th1/Th2 cytokines in H22 hepatocarcinoma tumor-bearing mice. The results demonstrated that GP inhibits tumor progression. In the lymph nodes of the tumor microenvironment and spleen, the proportion of Treg cells was significantly higher in the tumor-bea...

  2. California Air Basins

    California Department of Resources — Air ResourcesCalifornia Air Resources BoardThe following datasets are from the California Air Resources Board: * arb_california_airbasins - California Air BasinsThe...

  3. Restoration of bearings

    Parker, R. J.; Zaretsky, E. V.; Hanau, H.


    Process consisting of grinding raceways to oversize but original quality condition and installing new oversize balls or bearings restores wornout ball and roller bearings to original quality, thereby doubling their operating life. Evaluations reveal process results in restoration of 90% of replaced bearings at less than 50% of new-bearing costs.

  4. Passive magnetic bearing configurations

    Post, Richard F.


    A journal bearing provides vertical and radial stability to a rotor of a passive magnetic bearing system when the rotor is not rotating and when it is rotating. In the passive magnetic bearing system, the rotor has a vertical axis of rotation. Without the journal bearing, the rotor is vertically and radially unstable when stationary, and is vertically stable and radially unstable when rotating.

  5. Maintenance Free Bearings

    S. M. Muzakkir & Harish Hirani


    In the present research work the need of a Maintenance Free Bearings (MFB) is established. The paper presents preliminary friction calculations to highlight the ways to achieve maintenance free bearings. The existing technologies of well established maintenance free bearings are described. The hybridization of bearing technologies to achieve low cost maintenance free bearings has been exemplified. Finally a combination of passive magnetic repulsion and hydrodynamics ha...

  6. Analecta of structures formed during the 28 June 1992 Landers-Big Bear, California earthquake sequence (including maps of shear zones, belts of shear zones, tectonic ridge, duplex en echelon fault, fault elements, and thrusts in restraining steps)

    Johnson, A.M.; Johnson, N.A.; Johnson, K.M.; Wei, W. [Purdue Univ., West Lafayette, IN (United States). Dept. of Earth and Atmospheric Sciences; Fleming, R.W. [Geological Survey, Denver, CO (United States); Cruikshank, K.M. [Portland State Univ., OR (United States). Dept. of Geology; Martosudarmo, S.Y. [BPP Technologi, Jakarta (Indonesia)


    The June 28, 1992, M{sub s} 7.5 earthquake at Landers, California, which occurred about 10 km north of the community of Yucca Valley, California, produced spectacular ground rupturing more than 80 km in length (Hough and others, 1993). The ground rupturing, which was dominated by right-lateral shearing, extended along at least four distinct faults arranged broadly en echelon. The faults were connected through wide transfer zones by stepovers, consisting of right-lateral fault zones and tension cracks. The Landers earthquakes occurred in the desert of southeastern California, where details of ruptures were well preserved, and patterns of rupturing were generally unaffected by urbanization. The structures were varied and well-displayed and, because the differential displacements were so large, spectacular. The scarcity of vegetation, the aridity of the area, the compactness of the alluvium and bedrock, and the relative isotropy and brittleness of surficial materials collaborated to provide a marvelous visual record of the character of the deformation zones. The authors present a series of analecta -- that is, verbal clips or snippets -- dealing with a variety of structures, including belts of shear zones, segmentation of ruptures, rotating fault block, en echelon fault zones, releasing duplex structures, spines, and ramps. All of these structures are documented with detailed maps in text figures or in plates (in pocket). The purpose is to describe the structures and to present an understanding of the mechanics of their formation. Hence, most descriptions focus on structures where the authors have information on differential displacements as well as spatial data on the position and orientation of fractures.

  7. Teddy Bear Stories

    van Leeuwen, Theo; Caldas-Coulthardt, Carmen


    This paper presents a semiotic analysis of a key cultural artefact, the teddy bear. After introducing the iconography of the teddy bear, it analyses different kinds of stories to show how teddy bears are endowed with meaning in everyday life: stories from children's books, reminiscenses by adults...

  8. Flywheel energy storage with superconductor magnetic bearings

    Weinberger, Bernard R.; Lynds, Jr., Lahmer; Hull, John R.


    A flywheel having superconductor bearings has a lower drag to lift ratio that translates to an improvement of a factor of ten in the rotational decay rate. The lower drag results from the lower dissipation of melt-processed YBCO, improved uniformity of the permanent magnet portion of the bearings, operation in a different range of vacuum pressure from that taught by the art, and greater separation distance from the rotating members of conductive materials.

  9. Qualification of high damping seismic isolation bearings for the ALMR

    The Advanced Liquid Metal Reactor (ALMR) seismic isolation system consists of high damping steel-laminated elastomeric bearings. This type of bearing is used worldwide to isolate buildings and large critical components. A comprehensive testing program has been developed to qualify the use of this system for the ALMR. The program includes material characterization tests, various scale bearing tests, full-size bearing tests, shake table tests, and long-term aging tests. The main tasks and objectives of this program are described in the paper. Additionally, a detailed assessment of completed ALMR bearing test results will be provided. This assessment will be mainly based on half-scale bearing tests performed at the Earthquake Engineering Research Center (EERC) of the University of California at Berkeley and at the Energy Technology Engineering Center (ETEC). These tests were funded by the U.S. Department of Energy (DOE). Both static and dynamic tests were performed. Bearings with two types of end connections were tested: dowelled and bolted. The parameters examined will include the vertical, horizontal stiffness and damping of the bearings under different loading conditions up to failure. This will determine the available margins in the bearings above the design vertical load and horizontal displacement. Additionally, the self-centering capability of the bearings after an earthquake will be addressed. On the basis of these findings, recommendations can be made if necessary, to improve current manufacturing procedures, quality control, and procurement specifications. (author)

  10. Effectiveness of elastic band-type ankle–foot orthoses on postural control in poststroke elderly patients as determined using combined measurement of the stability index and body weight-bearing ratio

    Kim JH


    Full Text Available Jong Hyun Kim, Woo Sang Sim, Byeong Hee Won Usability Evaluation Technology Center, Advanced Biomedical and Welfare R&D Group, Korea Institute of Industrial Technology, Cheonan-si, Chungcheongnam-do, South Korea Purpose: Poor recovery of postural stability poststroke is the primary cause of impairment in activities and social participation in elderly stroke survivors. The purpose of our study was to experimentally evaluate the effectiveness of our new elastic ankle–foot orthosis (AFO, compared to a traditional AFO fabricated with hard plastic, in improving postural stability in elderly chronic stroke survivors. Patients and methods: Postural stability was evaluated in ten chronic stroke patients, 55.7±8.43 years old. Postural stability was evaluated using the standardized methods of the Biodex Balance System combined with a foot pressure system, under three experimental conditions, no AFO, rigid plastic AFO, and elastic AFO (E-AFO. The following dependent variables of postural stability were analyzed: plantar pressure under the paretic and nonparetic foot, area of the center of balance (COB and % time spent in each location, distance traveled by the COB away from the body center, distance traveled by the center of pressure, and calculated index of overall stability, as well as indices anterior–posterior and medial–lateral stability. Results: Both AFO designs improved all indices of postural stability. Compared to the rigid plastic AFO, the E-AFO produced additional positive effects in controlling anterior–posterior body sway, equalizing weight bearing through the paretic and nonparetic limbs, and restraining the displacement of the center of pressure and of the COB. Conclusion: Based on our outcomes, we recommend the prescription of E-AFOs as part of a physiotherapy rehabilitation program to promote recovery of postural stability poststroke. When possible, therapeutic outcomes should be documented using the Biodex Balance System and

  11. Bear Spray Safety Program

    Blome, C.D.; Kuzniar, R.L.


    A bear spray safety program for the U.S. Geological Survey (USGS) was officially initiated by the Firearms Safety Committee to address accident prevention and to promote personnel training in bear spray and its transportation, storage, and use for defense against wild animals. Used as part of a system including firearms, or used alone for those who choose not to carry a firearm, bear spray is recognized as an effective tool that can prevent injury in a wild animal attack.

  12. Optimal Synchronizability of Bearings

    Araújo, N. A. M.; Seybold, H.; Baram, R. M.; Herrmann, H. J.; Andrade, J. S.


    Bearings are mechanical dissipative systems that, when perturbed, relax toward a synchronized (bearing) state. Here we find that bearings can be perceived as physical realizations of complex networks of oscillators with asymmetrically weighted couplings. Accordingly, these networks can exhibit optimal synchronization properties through fine tuning of the local interaction strength as a function of node degree [Motter, Zhou, and Kurths, Phys. Rev. E 71, 016116 (2005)]. We show that, in analogy...

  13. Bearing restoration by grinding

    Hanau, H.; Parker, R. J.; Zaretsky, E. V.; Chen, S. M.; Bull, H. L.


    A joint program was undertaken by the NASA Lewis Research Center and the Army Aviation Systems Command to restore by grinding those rolling-element bearings which are currently being discarded at aircraft engine and transmission overhaul. Three bearing types were selected from the UH-1 helicopter engine (T-53) and transmission for the pilot program. No bearing failures occurred related to the restoration by grinding process. The risk and cost of a bearing restoration by grinding programs was analyzed. A microeconomic impact analysis was performed.

  14. EcoBears

    Nielsen, Nick; Pedersen, Sandra Bleuenn; Sørensen, Jens Ager;


    In this paper, we introduce the EcoBears concept that aims to augment household appliances with functional and aesthetic features to promote their "use'' and "longevity of use'' to prevent their disposal. The EcoBears also aim to support the communication of environmental issues in the home setting....... We present our initial design and implementation of the EcoBears that consist of two bear modules (a mother and her cub). We also present our preliminary concept validations and lessons learned to be considered for future directions....

  15. Genomic sequencing of Pleistocene cave bears

    Noonan, James P.; Hofreiter, Michael; Smith, Doug; Priest, JamesR.; Rohland, Nadin; Rabeder, Gernot; Krause, Johannes; Detter, J. Chris; Paabo, Svante; Rubin, Edward M.


    Despite the information content of genomic DNA, ancient DNA studies to date have largely been limited to amplification of mitochondrial DNA due to technical hurdles such as contamination and degradation of ancient DNAs. In this study, we describe two metagenomic libraries constructed using unamplified DNA extracted from the bones of two 40,000-year-old extinct cave bears. Analysis of {approx}1 Mb of sequence from each library showed that, despite significant microbial contamination, 5.8 percent and 1.1 percent of clones in the libraries contain cave bear inserts, yielding 26,861 bp of cave bear genome sequence. Alignment of this sequence to the dog genome, the closest sequenced genome to cave bear in terms of evolutionary distance, revealed roughly the expected ratio of cave bear exons, repeats and conserved noncoding sequences. Only 0.04 percent of all clones sequenced were derived from contamination with modern human DNA. Comparison of cave bear with orthologous sequences from several modern bear species revealed the evolutionary relationship of these lineages. Using the metagenomic approach described here, we have recovered substantial quantities of mammalian genomic sequence more than twice as old as any previously reported, establishing the feasibility of ancient DNA genomic sequencing programs.

  16. Mercury biomagnification in polar bears ( Ursus maritimus)

    Horton, T. W.; Blum, J. D.; Xie, Z.; Hren, M.; Chamberlain, C. P.


    Mercury biomagnification occurs in a variety of ecosystems resulting in greater potential for toxicological effects in higher-level trophic feeders. However, Hg transport pathways through different foodweb channels are not well known, particularly in high-latitude systems affected by atmospheric Hg deposition associated with snow and ice. Stable carbon and nitrogen isotope ratios and Hg concentrations determined for 26 late 19th and early 20th century polar bear hair specimens collected from cataloged museum collections elucidate relationships between high latitude marine foodweb structure and Hg transport pathways. Nitrogen and carbon isotopic compositions suggest that polar bears derive nutrition from both open water (pelagic) and ice associated (sympagic) foodweb channels. Correlation between Hg concentrations and nitrogen isotope compositions indicate mercury biomagnification occurred in most of the polar bears investigated. Interpretation of stable isotope based foodweb structure in concert with Hg concentrations further suggests that Hg biomagnification occurred to a greater degree in polar bears participating in pelagic foodweb channels.

  17. Bearing fatigue investigation 3

    Nahm, A. H.; Bamberger, E. N.; Signer, H. R.


    The operating characteristics of large diameter rolling-element bearings in the ultra high speed regimes expected in advanced turbine engines for high performance aircraft were investigated. A high temperature lubricant, DuPont Krytox 143 AC, was evaluated at bearing speeds to 3 million DN. Compared to the results of earlier, similar tests using a MIL-L-23699 (Type II) lubricant, bearings lubricated with the high density Krytox fluid showed significantly higher power requirements. Additionally, short bearing lives were observed when this fluid was used with AISI M50 bearings in an air atmosphere. The primary mode of failure was corrosion initiated surface distress (fatigue) on the raceways. The potential of a case-carburized bearing to sustain a combination of high-tangential and hertzian stresses without experiencing race fracture was also investigated. Limited full scale bearing tests of a 120 mm bore ball bearing at a speed of 25,000 rpm (3 million DN) indicated that a carburized material could sustain spalling fatigue without subsequent propagation to fracture. Planned life tests of the carburized material had to be aborted, however, because of apparent processing-induced material defects.

  18. Arcturus and the Bears

    Antonello, E.


    Arcturus is the brightest star in Bootes. The ancient Greek name Arktouros means Bear Guard. The star, however, is not close to Ursa Maior (Big She-Bear) and Ursa Minor (Little She-Bear), as the name would suggest. This curious discrepancy could be explained by the star proper motion, assuming the name Bear Guard is a remote cultural heritage. The proper motion analysis could allow us to get an insight also into an ancient myth regarding Ursa Maior. Though we cannot explain scientifically such a myth, some interesting suggestions can be obtained about its possible origin, in the context of the present knowledge of the importance of the cult of the bear both during the Palaeolithic times and for several primitive populations of modern times, as shown by the ethnological studies.

  19. California Political Districts

    California Department of Resources — This is a series of district layers pertaining to California'spolitical districts, that are derived from the California State Senateand State Assembly information....

  20. Ultra-precision bearings

    Wardle, F


    Ultra-precision bearings can achieve extreme accuracy of rotation, making them ideal for use in numerous applications across a variety of fields, including hard disk drives, roundness measuring machines and optical scanners. Ultraprecision Bearings provides a detailed review of the different types of bearing and their properties, as well as an analysis of the factors that influence motion error, stiffness and damping. Following an introduction to basic principles of motion error, each chapter of the book is then devoted to the basic principles and properties of a specific type of bearin

  1. Management recommendations: Bear River

    US Fish and Wildlife Service, Department of the Interior — This document is a review of land management practices at the Bear River Migratory Bird Refuge, by a land use specialist. Recommendations, time frame and additional...

  2. Gear bearing drive

    Weinberg, Brian (Inventor); Mavroidis, Constantinos (Inventor); Vranish, John M. (Inventor)


    A gear bearing drive provides a compact mechanism that operates as an actuator providing torque and as a joint providing support. The drive includes a gear arrangement integrating an external rotor DC motor within a sun gear. Locking surfaces maintain the components of the drive in alignment and provide support for axial loads and moments. The gear bearing drive has a variety of applications, including as a joint in robotic arms and prosthetic limbs.

  3. Rolling bearing analysis

    Harris, Tedric A


    One of the most well-known experts in the field brings cutting-edge research to practitioners in the new edition of this important reference. Covers the improved mathematical calculations for rolling bearing endurance developed by the American Society of Mechanical Engineers and the Society of Lubrication and Tribology Engineers. Updated with new material on Condition-Based Maintenance, new testing methods, and new bearing materials.

  4. My Little Teddy Bear



    @@ As Valentine's Day came closer,every shop was full of colourful gifts such as cookies in the shape of heart, chocolates,Teddy Bears and so on.When I step into a shop on February 14th,I felt most lonely as I was alone.With mv eves fixed on a lovely Teddy Bear, I wished that someone could send me this stuffed toy.

  5. Wear fault diagnosis of an emulsion pump crank bearing

    HAN Xiao-ming; DU Chang-long; ZHANG Yong-zhong; TIE Zhan-xu


    The total load on a crank bearing was calculated by performing a load analysis of the crank connecting rod mechanism.The Reynolds equation for hydrodynamic lubrication of the crank bearing was established at the Reynolds boundary condition and was then solved using the Holland method. From this the regular track of the bearing axis was obtained. As the crank bearing gradually wears the eccentricity ratio corresponding to the minimum oil film thickness increases gradually. The oil-bound film eventually breaks down, which allows friction and collision between the metal surfaces of the crank pin and the bearing. The rigid impact leads to excitation of high frequency vibrations at the natural frequencies of the connecting rod. The experiments show that the wear condition of the crank bearing can be identified correctly through the vibration signature at the natural frequencies of the connecting rod. The degree of wear can be predicted accurately through the energy content of the high frequency bands.

  6. Climate Drives Polar Bear Origins

    In their provocative analysis of northern bears (“Nuclear genomic sequences reveal that polar bears are an old and distinct bear lineage,” Reports, 20 April, p. 344), F. Hailer et al. use independent nuclear loci to show that polar bears originated during the middle Pleistocene, rather than during t...

  7. Partial tooth gear bearings

    Vranish, John M. (Inventor)


    A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

  8. Blood Pump Bearing System

    Aber, Gregory S. (Inventor)


    An apparatus is provided for a blood pump bearing system within a pump housing to support long-term highspeed rotation of a rotor with an impeller blade having a plurality of individual magnets disposed thereon to provide a small radial air gap between the magnets and a stator of less than 0.025 inches. The bearing system may be mounted within a flow straightener, diffuser, or other pump element to support the shaft of a pump rotor. The bearing system includes a zirconia shaft having a radiused end. The radiused end has a first radius selected to be about three times greater than the radius of the zirconia shaft. The radiused end of the zirconia shaft engages a flat sapphire endstone. Due to the relative hardness of these materials a flat is quickly produced during break-in on the zirconia radiused end of precisely the size necessary to support thrust loads whereupon wear substantially ceases. Due to the selection of the first radius, the change in shaft end-play during pump break-in is limited to a total desired end-play of less than about 0.010 inches. Radial loads are supported by an olive hole ring jewel that makes near line contact around the circumference of the Ir shaft to support big speed rotation with little friction. The width of olive hole ring jewel is small to allow heat to conduct through to thereby prevent heat build-up in the bearing. A void defined by the bearing elements may fill with blood that then coagulates within the void. The coagulated blood is then conformed to the shape of the bearing surfaces.

  9. Modular gear bearings

    Vranish, John M. (Inventor)


    A gearing system using modular gear bearing components. Each component is composed of a core, one or more modules attached to the core and two or more fastening modules rigidly attaching the modules to the core. The modules, which are attached to the core, may consist of gears, rollers or gear bearing components. The core orientation affects the orientation of the modules attached to the core. This is achieved via the keying arrangement of the core and the component modules that attach to the core. Such an arrangement will also facilitate the phase tuning of gear modules with respect to the core and other gear modules attached to the core.

  10. Study on mechanical properties of laminated rubber bearing with small shape factor

    Laminated rubber bearings with a small shape factor are regarded as one of the most promising isolation devices to reduce the vertical seismic load of a nuclear power plant. In this study, three types of natural rubber bearings with different aspect ratios (diameter/total thickness of rubber) and one high-damping rubber bearing are tested under varied loading conditions. Basic characteristics and ultimate characteristics of the bearings are made clear, and applicability of estimation formula and analysis method are verified

  11. Study on mechanical properties of laminated rubber bearing with small shape factor

    Mazda, T. [Kyushu Univ., Fukuoka (Japan); Ootori, Y.; Yabana, S.; Hirata, K.; Ishida, K. [Central Research Inst. of Electric Power Industry, Chiba (Japan)


    Laminated rubber bearings with a small shape factor are regarded as one of the most promising isolation devices to reduce the vertical seismic load of a nuclear power plant. In this study, three types of natural rubber bearings with different aspect ratios (diameter/total thickness of rubber) and one high-damping rubber bearing are tested under varied loading conditions. Basic characteristics and ultimate characteristics of the bearings are made clear, and applicability of estimation formula and analysis method are verified.

  12. Research on bearing life prediction based on support vector machine and its application

    Life prediction of rolling element bearing is the urgent demand in engineering practice, and the effective life prediction technique is beneficial to predictive maintenance. Support vector machine (SVM) is a novel machine learning method based on statistical learning theory, and is of advantage in prediction. This paper develops SVM-based model for bearing life prediction. The inputs of the model are features of bearing vibration signal and the output is the bearing running time-bearing failure time ratio. The model is built base on a few failed bearing data, and it can fuse information of the predicted bearing. So it is of advantage to bearing life prediction in practice. The model is applied to life prediction of a bearing, and the result shows the proposed model is of high precision.

  13. Flexure Bearing Reduces Startup Friction

    Clingman, W. Dean


    Design concept for ball bearing incorporates small pieces of shim stock, wire spokes like those in bicycle wheels, or other flexing elements to reduce both stiction and friction slope. In flexure bearing, flexing elements placed between outer race of ball bearing and outer ring. Elements flex when ball bearings encounter small frictional-torque "bumps" or even larger ones when bearing balls encounter buildups of grease on inner or outer race. Flexure of elements reduce high friction slopes of "bumps", helping to keep torque between outer ring and inner race low and more nearly constant. Concept intended for bearings in gimbals on laser and/or antenna mirrors.

  14. California sea lions (Zalophus californianus californianus) have lower chlorinated hydrocarbon contents in northern Baja California, Mexico, than in California, USA

    Del Toro, Ligeia [Universidad Autonoma de Baja California (UABC), Facultad de Ciencias Marinas, Ensenada, Baja California (Mexico); Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico); Heckel, Gisela [Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico) and Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, B.C. Km 107 Carretera Tijuana-Ensenada, Ensenada, Baja California 22860 (Mexico)]. E-mail:; Camacho-Ibar, Victor F. [Instituto de Investigaciones Oceanologicas, UABC, Apdo. Postal 453, Ensenada, Baja California 22860 (Mexico); Schramm, Yolanda [Universidad Autonoma de Baja California (UABC), Facultad de Ciencias Marinas, Ensenada, Baja California (Mexico); Investigacion y Conservacion de Mamiferos Marinos de Ensenada, A.C., Placido Mata 2309 Depto. D-5, Condominio Las Fincas, Ensenada, Baja California 22810 (Mexico)


    Chlorinated hydrocarbons (CHs) were determined in blubber samples of 18 California sea lions (Zalophus californianus californianus) that stranded dead along Todos Santos Bay, Ensenada, Baja California, Mexico, January 2000-November 2001. {sigma}DDTs were the dominant group (geometric mean 3.8 {mu}g/g lipid weight), followed by polychlorinated biphenyls ({sigma}PCBs, 2.96 {mu}g/g), chlordanes (0.12 {mu}g/g) and hexachlorocyclohexanes (0.06 {mu}g/g). The {sigma}DDTs/{sigma}PCBs ratio was 1.3. We found CH levels more than one order of magnitude lower than those reported for California sea lion samples collected along the California coast, USA, during the same period as our study. This sharp north-south gradient suggests that Z. californianus stranded in Ensenada (most of them males) would probably have foraged during the summer near rookeries 500-1000 km south of Ensenada and the rest of the year migrate northwards, foraging along the Baja California peninsula, including Ensenada, and probably farther north. - Results suggest that sea lion prey must also have lower hydrocarbons in Baja California than in California in the USA.

  15. California sea lions (Zalophus californianus californianus) have lower chlorinated hydrocarbon contents in northern Baja California, Mexico, than in California, USA

    Chlorinated hydrocarbons (CHs) were determined in blubber samples of 18 California sea lions (Zalophus californianus californianus) that stranded dead along Todos Santos Bay, Ensenada, Baja California, Mexico, January 2000-November 2001. ΣDDTs were the dominant group (geometric mean 3.8 μg/g lipid weight), followed by polychlorinated biphenyls (ΣPCBs, 2.96 μg/g), chlordanes (0.12 μg/g) and hexachlorocyclohexanes (0.06 μg/g). The ΣDDTs/ΣPCBs ratio was 1.3. We found CH levels more than one order of magnitude lower than those reported for California sea lion samples collected along the California coast, USA, during the same period as our study. This sharp north-south gradient suggests that Z. californianus stranded in Ensenada (most of them males) would probably have foraged during the summer near rookeries 500-1000 km south of Ensenada and the rest of the year migrate northwards, foraging along the Baja California peninsula, including Ensenada, and probably farther north. - Results suggest that sea lion prey must also have lower hydrocarbons in Baja California than in California in the USA

  16. Mercury and Selenium in Muscle and Target Organs of Scalloped Hammerhead Sharks Sphyrna lewini of the SE Gulf of California: Dietary Intake, Molar Ratios, Loads, and Human Health Risks.

    Bergés-Tiznado, Magdalena E; Márquez-Farías, Fernando; Lara-Mendoza, Raúl E; Torres-Rojas, Yassir E; Galván-Magaña, Felipe; Bojórquez-Leyva, Humberto; Páez-Osuna, Federico


    Selenium and mercury were evaluated in muscle, liver, kidney, brain, and the stomach contents of juvenile scalloped hammerhead shark Sphyrna lewini. Se:Hg molar ratios were calculated. The average Hg levels in muscle ranged from 0.12 to 1.17 μg/g (wet weight); Hg was 1. Correlations were found for Hg in muscle with size, age, and weight, and also for Hg in liver with size, age, and weight. Hg in muscle was significantly positive correlated to Hg in brain as well as Hg in liver was correlated to Hg in kidney. The highest Hg in preys was for carangid fishes; scombrid and carangid fishes contributed with the highest Se levels. Results suggest that more than 98 % of the total Hg and 62 % of Se end up in muscle and might be affected by factors, such as geographical area, age, size, and feeding habits. The muscle of S. lewini should be consumed by people cautiously so as not to exceed the recommended intake per week. PMID:26369650

  17. The thermodynamic properties of a new type catcher bearing used in active magnetic bearings system

    Normally a rotor levitated by active magnetic bearings (AMBs) system would rotate without contacting with any stator component, but the possibility still remains that the supporting force might lose temporarily or permanently, thus requiring the Catcher bearings (CBs) to provide backup protection in case of the failure of AMBs. A new type CB with two separate rolling element bearing series could have the speed distribution between the inner race and intermediate race according to certain ratio, in which the speed of each roller element bearing decreases with the limit speed of the whole CB increasing, offering high capability to sustain its initial rotation speed. Based on the theory of heat transfer, tribology, and rotor dynamics, this paper analyzes the thermal structure of double-decker catcher bearing (DDCB) and single-decker catcher bearing (SDCB), respectively. Through this structure, the thermal resistances and equations of heat transfer can be obtained. Then we calculate the friction heat and temperature distribution in the various CBs upon rotor's dropping on SDCB or DDCB, followed by the discussion on the CBs temperature rise's effects on lubrication conditions and rotor dynamics parameters. Finally various experiments are carried out to measure the temperature rise of different CBs. The results obtained validate the theoretical analysis and also provide main methods to reduce heat generation. Using DDCB is proved to be effective to reduce the temperature rise. - Highlights: • The DDCB is a more suitable catcher bearing for AMBs. • Compared to SDCB, using DDCB, the temperature rise can decrease in the same states. • A lower viscosity of lubricant may induce a lower temperature rise. • The inner raceway temperature of the first layer bearing is the highest. • Reducing the unbalance mass of the rotor is a method to decrease the temperature rise

  18. Ancestral polymorphisms and sex-biased migration shaped the demographic history of brown bears and polar bears.

    Shigeki Nakagome

    Full Text Available Recent studies have reported discordant gene trees in the evolution of brown bears and polar bears. Genealogical histories are different among independent nuclear loci and between biparentally inherited autosomal DNA (aDNA and matrilineal mitochondrial DNA (mtDNA. Based on multi-locus genomic sequences from aDNA and mtDNA, we inferred the population demography of brown and polar bears and found that brown bears have 6 times (aDNA or more than 14 times (mtDNA larger population sizes than polar bears and that polar bear lineage is derived from within brown bear diversity. In brown bears, the effective population size ratio of mtDNA to aDNA was at least 0.62, which deviated from the expected value of 0.25, suggesting matriarchal population due to female philopatry and male-biased migration. These results emphasize that ancestral polymorphisms and sex-biased migration may have contributed to conflicting branching patterns in brown and polar bears across aDNA genes and mtDNA.

  19. Teale California shoreline

    California Department of Resources — California Spatial Information System (CaSIL) is a project designed to improve access to geo-spatial and geo-spatial related data information throughout the state...

  20. California Condor Critical Habitat

    California Department of Resources — These Data identify (in general) the areas where critical habitat for the California Condor occur. Critical habitat for the species consists of the following 10...

  1. Reliability for fluid bearings design

    DIOP, Khadim; CHARKI, Abdérafi; CHAMPMARTIN, Stéphane; AMBARI, Abdelhak


    This paper presents a new methodology for evaluating the failure probability of fluid bearings which are sensitive components for the design of machine rotors, mechatronic systems and high precision metrology. The static and dynamic behavior of a fluid bearing depends on several parameters, such as external load, bearing dimensions, supply pressure, quality of the machined surfaces, fluid properties, etc. In this paper, the characteristics of a simple geometry thrust bearing are calculated an...

  2. Reliability of a hydrostatic bearing

    CHARKI, Abderafi; DIOP, Khadim; CHAMPMARTIN, Stéphane; AMBARI, Abdelhak


    This paper presents a methodology for evaluating the failure probability of fluid bearings, which are sensitive components for the design of machine rotors, mechatronic systems, and high precision metrology. The static and dynamic behavior of a fluid bearing depends on several parameters, such as external load, bearing dimensions, supply pressure, quality of the machined surfaces, fluid properties, etc. In this paper, the characteristics of a simple geometry hydrostatic bearing are calculated...

  3. Households' Interest-bearing Assets

    Ellis Connolly; Fiona Fleming; Jarkko Jääskelä


    Households invest around two-fifths of their financial assets in interest-bearing assets. These assets are predominantly held directly in deposits and also via superannuation and other investment funds. Deposits have grown strongly in recent years, although there has been no growth in interest-bearing securities. Compared with other advanced economies, interest-bearing assets represent a relatively small share of financial assets. For the household sector as a whole, interest-bearing assets a...

  4. Centrifugally decoupling touchdown bearings

    Post, Richard F


    Centrifugally decoupling mechanical bearing systems provide thin tensioned metallic ribbons contained in a support structure. This assembly rotates around a stationary shaft being centered at low speeds by the action of the metal ribbons. Tension springs are connected on one end to the ribbons and on the other end to the support structure. The ribbons pass through slots in the inner ring of the support structure. The spring preloading thus insures contact (or near-contact) between the ribbons and the shaft at rotation speeds below the transition speed. Above this speed, however, the centrifugal force on the ribbons produces a tensile force on them that exceeds the spring tensile force so that the ribbons curve outward, effectively decoupling them from mechanical contact with the shaft. They still remain, however, in position to act as a touchdown bearing in case of abnormally high transverse accelerations.

  5. Government Risk-Bearing


    The u.s. government bulks large in the nation's financial markets. The huge volume of government-issued and -sponsored debt affects the pricing and volume ofprivate debt and, consequently, resource allocation between competing alternatives. What is often not fully appreciated is the substantial influence the federal government wields overresource allocation through its provisionofcreditandrisk-bearing services to the private economy. Because peopleand firms generally seekto avoid risk, atsomeprice they are willing to pay another party to assume the risk they would otherwise face. Insurance companies are a class of private-sector firms one commonly thinks of as providing these services. As the federal government has expanded its presence in the U.S. economy during this century, it has increasingly developed programs aimed at bearing risks that the private sector either would not take on at any price, or would take on but atapricethoughtto besogreatthatmostpotentialbeneficiarieswouldnotpurchase the coverage. To...

  6. Rotating plug bearing and seal

    Wade, Elman E.


    A bearing and seal structure for nuclear reactors utilizing rotating plugs above the nuclear reactor vessel. The structure permits lubrication of bearings and seals of the rotating plugs without risk of the lubricant draining into the reactor vessel below. The structure permits lubrication by utilizing a rotating outer race bearing.

  7. Rotating plug bearing and seal

    Disclosed is a bearing and seal structure for nuclear reactors utilizing rotating plugs above the nuclear reactor vessel. The structure permits lubrication of bearings and seals of the rotating plugs without risk of the lubricant draining into the reactor vessel below. The structure permits lubrication by utilizing a rotating outer race bearing. 19 claims, 3 figures

  8. Pooh Bear rock and Mermaid Dune


    One of the two forward cameras aboard Sojourner imaged this area of Martian terrain on Sol 26. The large rock dubbed 'Pooh Bear' is at far left, and stands between four and five inches high. Mermaid Dune is the smooth area stretching horizontally across the top quarter of the image. The Alpha Proton X-Ray Spectrometer (APXS) instrument aboard Sojourner will be deployed on Mermaid Dune, and the rover will later use its cleated wheels to dig into it.Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages and Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

  9. ANSWER: A bear paw.

    Ian BICKLE


    (Refer to page 186)Answer: Bear Paw sign of Xanthogranulomatous PyelonephritisThe contrast enhanced (portal venous phase)CT of the abdomen showed a global enlargement of the right kidney. There are multiplelow attenuation areas in the renal parenchyma, in a ‘hydronephrotic type manner’, but with no true hydronephrosis. This is due to a renal calculus lying in a contracted pelvis with dilated calyces that contain inflammatory debris. A rim of normal renal tissue enhancesperipherally. The appea...

  10. Envera Variable Compression Ratio Engine

    Charles Mendler


    the compression ratio can be raised (to as much as 18:1) providing high engine efficiency. It is important to recognize that for a well designed VCR engine cylinder pressure does not need to be higher than found in current production turbocharged engines. As such, there is no need for a stronger crankcase, bearings and other load bearing parts within the VCR engine. The Envera VCR mechanism uses an eccentric carrier approach to adjust engine compression ratio. The crankshaft main bearings are mounted in this eccentric carrier or 'crankshaft cradle' and pivoting the eccentric carrier 30 degrees adjusts compression ratio from 9:1 to 18:1. The eccentric carrier is made up of a casting that provides rigid support for the main bearings, and removable upper bearing caps. Oil feed to the main bearings transits through the bearing cap fastener sockets. The eccentric carrier design was chosen for its low cost and rigid support of the main bearings. A control shaft and connecting links are used to pivot the eccentric carrier. The control shaft mechanism features compression ratio lock-up at minimum and maximum compression ratio settings. The control shaft method of pivoting the eccentric carrier was selected due to its lock-up capability. The control shaft can be rotated by a hydraulic actuator or an electric motor. The engine shown in Figures 3 and 4 has a hydraulic actuator that was developed under the current program. In-line 4-cylinder engines are significantly less expensive than V engines because an entire cylinder head can be eliminated. The cost savings from eliminating cylinders and an entire cylinder head will notably offset the added cost of the VCR and supercharging. Replacing V6 and V8 engines with in-line VCR 4-cylinder engines will provide high fuel economy at low cost. Numerous enabling technologies exist which have the potential to increase engine efficiency. The greatest efficiency gains are realized when the right combination of advanced and new

  11. Study of a four Titled Pad Bearing

    Ibrahim A. Mohsen


    Full Text Available This research deal with an analytical study of a four titled pad bearing. These pads are arranged around the journal. A computer program has been used to solve Reynolds equation numerically using the finite difference technique.            The results showed that, the non dimensional force is increased with the increase of the non dimensional load and the gradient of the curve is increased with the decrease of the ( ratio. while the gradient is decreased with the increase of the number of pads which gives less power absorption due to the decrease of the friction force.            Also the results showed  that the eccentricity ratio is in the range of (0.4-0.8 and the maximum attitude angle is (43o. The curve of the relation between the eccentricity ratio and the load number does not start from the zero.            It has been noticed that the increase of the friction factor cause an increase in Summerfield number and the curve gradient is increase with the decrease of the ( ratio. Also the gradient is increased for a fixed value of the ( ratio with the decrease of external load, where as the decrease of the ( ratio cause a decrease of the oil film thickness and this cause an increase of the shearing rate.             Finally, the oil flow rate is increased with the increase of the ( ratio and this would increased more with the increase of the number of pads for the same value of ( ratio which leads to a decrease of the bearing temperature and this maintain the same value of the oil film thickness due to maintaining the same viscosity for the lubricant.

  12. Population dynamics of Virginia's hunted black bear (Ursus americanus) population.

    Klenzendorf, Sybille A.


    The Cooperative Alleghany Bear Study (CABS) was initiated in 1994 by the Virginia Department of Game and Inland Fisheries (VDGIF) and the Virginia Polytechnic Institute and State University (VPI&SU) to investigate population dynamics on Virginiaâ s hunted bear population. CABS personnel handled 746 different bears (1.5M:1F) 1,368 times on its northern study area during June 1994 to September 2000. The sex ratio for summer captures was 1.5M:1F, which differed from 1:1 (n = 1,008, Z = 6.17,...

  13. Anti-backlash gear bearings

    Vranish, John M. (Inventor)


    A gear bearing having a first gear and a second gear, each having a plurality of teeth. Each gear operates on two non-parallel surfaces of the opposing gear teeth to perform both gear and bearing functions simultaneously. The gears are moving at substantially the same speed at their contact points. The gears may be roller gear bearings or phase-shifted gear bearings, and may be arranged in a planet/sun system or used as a transmission. One preferred embodiment discloses and describes an anti-backlash feature to counter ''dead zones'' in the gear bearing movement.

  14. Introgressive hybridization: brown bears as vectors for polar bear alleles.

    Hailer, Frank


    The dynamics and consequences of introgression can inform about numerous evolutionary processes. Biologists have therefore long been interested in hybridization. One challenge, however, lies in the identification of nonadmixed genotypes that can serve as a baseline for accurate quantification of admixture. In this issue of Molecular Ecology, Cahill et al. (2015) analyse a genomic data set of 28 polar bears, eight brown bears and one American black bear. Polar bear alleles are found to be introgressed into brown bears not only near a previously identified admixture zone on the Alaskan Admiralty, Baranof and Chichagof (ABC) Islands, but also far into the North American mainland. Elegantly contrasting admixture levels at autosomal and X chromosomal markers, Cahill and colleagues infer that male-biased dispersal has spread these introgressed alleles away from the Late Pleistocene contact zone. Compared to a previous study on the ABC Island population in which an Alaskan brown bear served as a putatively admixture-free reference, Cahill et al. (2015) utilize a newly sequenced Swedish brown bear as admixture baseline. This approach reveals that brown bears have been impacted by introgression from polar bears to a larger extent (up to 8.8% of their genome), than previously known, including the bear that had previously served as admixture baseline. No evidence for introgression of brown bear into polar bear is found, which the authors argue could be a consequence of selection. Besides adding new exciting pieces to the puzzle of polar/brown bear evolutionary history, the study by Cahill and colleagues highlights that wildlife genomics is moving from analysing single genomes towards a landscape genomics approach. PMID:25775930

  15. Bearings only naval tracking

    Barth, M.J.


    Two commonly used Extended Kalman Filter tracking algorithms utilize the Relative Cartesian and Modified Polar coordinate systems. This report compares the two algorithms by exercising a destroyer-Submarine (DD/SS) computer simulation. A simple engagement geometry is employed which encompasses the major DD/SS options available. Error statistics are developed by Monte Carlo methods. Results are presented which show that the circular error depends upon the diagonal values of the error covariance matrix. The results also support (but do not establish) that the optimum DD manuevuer is that which minimizes the range while maximizing the bearing rate. 4 refs., 5 figs., 4 tabs.

  16. Self lubricating fluid bearings

    The invention concerns self lubricating fluid bearings, which are used in a shaft sealed system extending two regions. These regions contain fluids, which have to be isolated. A first seal is fluid tight for the first region between the carter shaft and the shaft. The second seal is fluid tight between the carter and the shaft, it communicates with the second region. The first fluid region is the environment surrounding the shaft carter. The second fluid region is a part of a nuclear reactor which contains the cooling fluid. The shaft is conceived to drive a reactor circulating and cooling fluid

  17. Bear-baiting may exacerbate wolf-hunting dog conflict.

    Joseph K Bump

    Full Text Available BACKGROUND: The influence of policy on the incidence of human-wildlife conflict can be complex and not entirely anticipated. Policies for managing bear hunter success and depredation on hunting dogs by wolves represent an important case because with increasing wolves, depredations are expected to increase. This case is challenging because compensation for wolf depredation on hunting dogs as compared to livestock is less common and more likely to be opposed. Therefore, actions that minimize the likelihood of such conflicts are a conservation need. METHODOLOGY/PRINCIPAL FINDINGS: We used data from two US states with similar wolf populations but markedly different wolf/hunting dog depredation patterns to examine the influence of bear hunting regulations, bear hunter to wolf ratios, hunter method, and hunter effort on wolf depredation trends. Results indicated that the ratio of bear hunting permits sold per wolf, and hunter method are important factors affecting wolf depredation trends in the Upper Great Lakes region, but strong differences exist between Michigan and Wisconsin related in part to the timing and duration of bear-baiting (i.e., free feeding. The probability that a wolf depredated a bear-hunting dog increases with the duration of bear-baiting, resulting in a relative risk of depredation 2.12-7.22× greater in Wisconsin than Michigan. The net effect of compensation for hunting dog depredation in Wisconsin may also contribute to the difference between states. CONCLUSIONS/SIGNIFICANCE: These results identified a potential tradeoff between bear hunting success and wolf/bear-hunting dog conflict. These results indicate that management options to minimize conflict exist, such as adjusting baiting regulations. If reducing depredations is an important goal, this analysis indicates that actions aside from (or in addition to reducing wolf abundance might achieve that goal. This study also stresses the need to better understand the relationship

  18. Superconducting bearings in flywheels

    Coombs, T.A.; Campbell, A.M.; Ganney, I.; Lo, W. [Cambridge Univ. (United Kingdom). Interdisciplinary Research Centre in Superconductivity (IRC); Twardowski, T. [International Energy Systems, Chester High Road, Neston, South Wirral (United Kingdom); Dawson, B. [British Nuclear Fuels, Capenhurst, South Wirral (United Kingdom)


    Investigations are being carried out into the use of superconducting magnetic bearings to levitate energy storage flywheels. In a planned program of work, Cambridge University are aiming to produce a practical bearing system for Pirouette(TM). The Pirouette(TM) system is designed to provide 5 kWh of recoverable energy which is currently recoverable at a rate of 5 kW (future revisions will provide up to 50 kW). IES (a British Nuclear Fuels subsidiary) the owners of the Pirouette(TM) machine have supplied Cambridge with a flywheel. This flywheel weighs >40 kg and is being levitated using an Evershed-type arrangement in which the superconductor is being used to stabilize the interaction between two magnets. To date we have demonstrated stable levitation in static and low speed tests in a rig designed for low speeds of rotation in air. A second rig which is currently under construction at BNFL will run in vacuum at speeds of up to 50 (orig.) 5 refs.

  19. Superconducting bearings in flywheels

    Investigations are being carried out into the use of superconducting magnetic bearings to levitate energy storage flywheels. In a planned program of work, Cambridge University are aiming to produce a practical bearing system for Pirouette(TM). The Pirouette(TM) system is designed to provide 5 kWh of recoverable energy which is currently recoverable at a rate of 5 kW (future revisions will provide up to 50 kW). IES (a British Nuclear Fuels subsidiary) the owners of the Pirouette(TM) machine have supplied Cambridge with a flywheel. This flywheel weighs >40 kg and is being levitated using an Evershed-type arrangement in which the superconductor is being used to stabilize the interaction between two magnets. To date we have demonstrated stable levitation in static and low speed tests in a rig designed for low speeds of rotation in air. A second rig which is currently under construction at BNFL will run in vacuum at speeds of up to 50 (orig.)

  20. Computational design of rolling bearings

    Nguyen-Schäfer, Hung


    This book comprehensively presents the computational design of rolling bearings dealing with many interdisciplinary difficult working fields. They encompass elastohydrodynamics (EHD), Hertzian contact theory, oil-film thickness in elastohydrodynamic lubrication (EHL), bearing dynamics, tribology of surface textures, fatigue failure mechanisms, fatigue lifetimes of rolling bearings and lubricating greases, Weibull distribution, rotor balancing, and airborne noises (NVH) in the rolling bearings. Furthermore, the readers are provided with hands-on essential formulas based on the up-to-date DIN ISO norms and helpful examples for computational design of rolling bearings. The topics are intended for undergraduate and graduate students in mechanical and material engineering, research scientists, and practicing engineers who want to understand the interactions between these working fields and to know how to design the rolling bearings for automotive industry and many other industries.

  1. Grease lubrication in rolling bearings

    Lugt, Piet M


    The definitive book on the science of grease lubrication for roller and needle bearings in industrial and vehicle engineering. Grease Lubrication in Rolling Bearings provides an overview of the existing knowledge on the various aspects of grease lubrication (including lubrication systems) and the state of the art models that exist today. The book reviews the physical and chemical aspects of grease lubrication, primarily directed towards lubrication of rolling bearings. The first part of the book covers grease composition, properties and rheology, including thermal

  2. Reemerging Leptospirosis, California

    Meites, Elissa; Jay, Michele T.; Deresinski, Stanley; Shieh, Wun-Ju; Zaki, Sherif R.; Tompkins, Lucy; Smith, D. Scott


    Leptospirosis is a reemerging infectious disease in California. Leptospirosis is the most widespread zoonosis throughout the world, though it is infrequently diagnosed in the continental United States. From 1982 to 2001, most reported California cases occurred in previously healthy young adult white men after recreational exposures to contaminated freshwater. We report five recent cases of human leptospirosis acquired in California, including the first documented common-source outbreak of hum...

  3. Hydrostatic and hybrid bearing design

    Rowe, W B


    Hydrostatic and Hybrid Bearing Design is a 15-chapter book that focuses on the bearing design and testing. This book first describes the application of hydrostatic bearings, as well as the device pressure, flow, force, power, and temperature. Subsequent chapters discuss the load and flow rate of thrust pads; circuit design, flow control, load, and stiffness; and the basis of the design procedures and selection of tolerances. The specific types of bearings, their design, dynamics, and experimental methods and testing are also shown. This book will be very valuable to students of engineering des

  4. Fish of Bear Lake, Utah

    Palacios, Patsy; Luecke, Chris; Robinson, Justin


    There are 13 species of fish found in the waters of Bear Lake. Of those 13, 4 are endemic (found only in Bear Lake). The 4 endemics species are Bonneville cisco, Bonneville whitefish, Bear Lake whitefish, and Bear Lake sculpin. Five of the remaining 9 fish species are native to the region, and 4 are exotic introductions. These native fishes are the Bonneville cutthroat trout, Utah sucker, redside shiner, speckled dace and Utah chub. The exotic fishes are lake trout, common carp, yellow p...

  5. Dynamic Analysis of Engine Bearings

    H. Hirani


    Full Text Available This paper presents a simple methodology to evaluate the stiffness and damping coefficients of an engine bearing over a load cycle. A rapid technique is used to determine the shaft ‘limit cycle’ under engine dynamic loads. The proposed theoretical model is based on short and long bearing approximations. The results obtained by present approximation are compared with those obtained by numerical method. The influence of thermal effects on the stiffness and damping coefficients is predicted by using a simplified thermal analysis. In order to illustrate the application of the proposed scheme, one engine main bearing and a connecting rod bearing are analysed.

  6. California's congestion management program

    One of the hottest topics in transportation planning today is California's Congestion Management Program (CMP). California's program has been suggested as a model to the rest of the United States for addressing transportation problems and for conforming to the federal Clean Air Act. This article introduces California's Congestion Management Program, describes some problems related to California's CMP legislation, outlines the major CMP elements, and briefly explains the issue of the environmental impact of CMPs. This information might assist others in developing their own CMP programs

  7. Autosizing Control Panel for Needle Bearing

    Prof.A.R.Wadhekar,; Ms Jyoti R. Rajput


    A needle roller bearing is a bearing which uses small cylindrical rollers. Bearings are used to reduce friction of any rotating surface. Needle bearings have a large surface in contact with the bearing outer surfaces as compared to ball bearings. There is less added clearance(Diameter of the shaft and the diameter of the bearing are different) so they are much compact. The structure consists of a needle cage which contains the needle rollersthemselves and an outer race (The housin...

  8. Load-Measuring Pot Bearing with Built-In Load Cell —Part I: Design and Performance

    Jeong-Rae Cho; Young Jin Kim; Jong-Won Kwark; Sung Yong Park; Won Jong Chin; Byung-Suk Kim


    This paper presents the underlying principle and the results of various performance evaluations for a load-measuring pot bearing with built-in load cell. The pot bearing composed of a pot made of steel in which an elastomer disk is inserted is a bearing supporting larger loads than the elastomeric bearing and accommodating rotational movement. Owing to a Poisson’s ratio close to 0.5, elastomer withstands hydrostatic pressure when confined in a rigid body. Accounting for...

  9. Superconducting bearings for flywheel applications

    Abrahamsen, A.B.


    A literature study on the application of superconducting bearings in energy storage flywheel systems. The physics of magnetic levitation and superconductors are presented in the first part of the report, followed by a discussion of the literature found onthe applications of superconducting bearings in flywheels.

  10. Superconducting bearings for flywheel applications

    Abrahamsen, A.B.


    A literature study on the application of superconducting bearings in energy storage flywheel systems. The physics of magnetic levitation and superconductors are presented in the first part of the report, followed by a discussion of the literature found onthe applications of superconducting bearings...

  11. What about the Javan Bear?

    Jentink, F.A.


    The other day I read in a dutch popular periodical a paper dealing with the different species of Bears and their geographical distribution. To my great surprise the Malayan Bear was mentioned from Java: the locality Java being quite new to me I wrote to the author of that paper and asked him some in

  12. California's English Learner Students

    Hill, Laura E.


    English Learner (EL) students in California's schools are numerous and diverse, and they lag behind their native-English-speaking peers. Closing the achievement gap for EL students has been a long-standing goal for California educators, and there are some signs of success. Now that EL funding and curriculum issues are receiving a fresh level of…

  13. Analytical Analysis of the Influence of Angular Misalignment on Ball Bearings Life

    Luis Miguel Corzo Rodríguez; Gonzalo González Rey


    Experiences in application of ball bearings have demonstrated that the influence of angular misalignment,radial clearance and curvature ratio has an influence on the durability of bearings. However, there isnot enough technical information about any methods that considers the effect of there threecharacteristics on the life span of ball bearings. As a solution to this problem a series of calculationswas put forward with the assistance of ISO Technical Specification 16281: 2008 to study the in...

  14. Space Station alpha joint bearing

    Everman, Michael R.; Jones, P. Alan; Spencer, Porter A.


    Perhaps the most critical structural system aboard the Space Station is the Solar Alpha Rotary Joint which helps align the power generation system with the sun. The joint must provide structural support and controlled rotation to the outboard transverse booms as well as power and data transfer across the joint. The Solar Alpha Rotary Joint is composed of two transition sections and an integral, large diameter bearing. Alpha joint bearing design presents a particularly interesting problem because of its large size and need for high reliability, stiffness, and on orbit maintability. The discrete roller bearing developed is a novel refinement to cam follower technology. It offers thermal compensation and ease of on-orbit maintenance that are not found in conventional rolling element bearings. How the bearing design evolved is summarized. Driving requirements are reviewed, alternative concepts assessed, and the selected design is described.

  15. Fire safety of rubber bearings

    The objective of the study is to experimentally evaluate the fire resistance of the natural-rubber bearings to be incorporated into a Fast Reactor (FBR) under study. Four experiments were performed to look at the effect of bearing diameters and heating conditions on the performance. The full-scale specimen sustained the design-basis load for more than 3.5 hours under 'standard fire.' Medium-size bearings showed resistance for 2-4 hours, according to heating temperatures. The paper also summarizes the methods and the results of simulation analyses of rubber bearings subjected to load/temperature conditions under fire. The vertical deformation of the bearings can be calculated very well, using the temperature profiles obtained from testing. However, the heat transfer analyses did not give good results, especially in the cases/portions where heat was generated due to rubber combustion. (author)

  16. Genomic evidence of geographically widespread effect of gene flow from polar bears into brown bears

    Cahill, J.; Stirling, I.; Kistler, L.; Salamzade, R.; Ersmark, E.; Fulton, T.; Stiller, M.; Green, R.; Shapiro, B.


    Polar bears are an arctic, marine adapted species that is closely related to brown bears. Genome analyses have shown that polar bears are distinct and genetically homogeneous in comparison to brown bears. However, these analyses have also revealed a remarkable episode of polar bear gene flow into the population of brown bears that colonized the Admiralty, Baranof and Chichagof islands (ABC islands) of Alaska. Here, we present an analysis of data from a large panel of polar bear and brown bear...

  17. Henry J. Mello: A Life in California Politics

    Mello, Henry; Jarrell, Randall; Regional History Project, UC Santa Cruz Library


    In an article summarizing his career, one newspaper characterized him as the "great graying grizzly bear of California politics," an old-style moderate Democrat whose career was animated by his dedication to his local district and his tireless efforts in behalf of its economic welfare. GOP legislator Bill Campbell once described Mello as "the only Democrat in the Senate with any experience as an entrepreneur," and one of the last of a dying breed of citizen legislators. Mello claims his appro...


    Emin GÜLLÜ


    Full Text Available During manufacturing, ideal dimension and mutual positioning of machine elements proposed in project desing can be achieved only within certain range of tolerances. These tolerances, being classified in two groups, related to micro and macro geometry of machine elements, don't have to effect the functioning of these elements. So, as for all machine elements, investigation of the effects of macro and micro tolerances for journal bearings is important. In this study, we have investigated the effect of macro geometric irregularities of journal bearings on performance characteristics. In this regard, we have studied the change of bearing performance in respect to deviation from ideal circle for an elliptic shaft with small ovality rolling in circular journal bearing.

  19. Bears, Big and Little. Young Discovery Library Series.

    Pfeffer, Pierre

    This book is written for children 5 through 10. Part of a series designed to develop their curiosity, fascinate them and educate them, this volume describes: (1) the eight species of bears, including black bear, brown bear, grizzly bear, spectacled bear, sun bear, sloth bear, polar bear, and giant panda; (2) geographical habitats of bears; (3)…

  20. eBear: An Expressive Bear-Like Robot

    Zhang, Xiao; Mollahosseini, Ali; B., Amir H. Kargar; Boucher, Evan; Voyles, Richard M.; Nielsen, Rodney; Mahoor, Mohammd H.


    This paper presents an anthropomorphic robotic bear for the exploration of human-robot interaction including verbal and non-verbal communications. This robot is implemented with a hybrid face composed of a mechanical faceplate with 10 DOFs and an LCD-display-equipped mouth. The facial emotions of the bear are designed based on the description of the Facial Action Coding System as well as some animal-like gestures described by Darwin. The mouth movements are realized by synthesizing emotions w...

  1. Census Snapshot: California

    Romero, Adam P; Rosky, Clifford J; Badgett, M. V. Lee; Gates, Gary J.


    Using data from the U.S. Census Bureau, this report provides demographic and economic information about same-sex couples and same-sex couples raising children in California. We compare same-sex “unmarried partners,” which the Census Bureau defines as an unmarried couple who “shares living quarters and has a close personal relationship,” to different-sex married couples in California. In many ways, the more than 107,000 same-sex couples living in California are similar to married coup...

  2. California Immigrants Today

    Cornelius, Wayne A.


    This paper will focus on the Mexico-origin component of the California immigrant population. Drawing on the results of field studies conducted throughout California and in west-central Mexico during the last ten years,the paper will describe how the profile of Mexican migration to California has changed since the 197Os, suggest explanations for these changes, and discuss their implications for public policy. Effects of the long-running economic crisis in Mexico and of the 1986 U.S. immigra-ti...

  3. A Dynamic Analysis of Hydrodynamic Wave Journal Bearings

    Ene, Nicoleta M.; Dimofte, Florin; Keith, Theo G.


    The purpose of this paper is to study the dynamic behavior of a three-wave journal bearing using a transient approach. The transient analysis permits the determination of the rotor behavior after the fractional frequency whirl appears. The journal trajectory is determined by solving a set of nonlinear equations of motion using the Runge-Katta method. The fluid film forces are computed by integrating the transient Reynolds equation at each time step location of the shaft with respect to the bearing. Because of the large values of the rotational speeds, turbulent effects were included in the computations. The influence of the temperature on the viscosity was also considered. Numerical results were compared to experimenta1 results obtained at the NASA Glenn Research Center. Comparisons of the theoretical results with experimental data were found to be in good agreement. The numerical and experimental results showed that the fluid film of a three-wave journal bearing having a diameter of 30 mm, a length of 27 mm, and a wave amplitude ratio greater than 0.15 is stable even at rotational speeds of 60,000 RPM. For lower wave amplitude ratios, the threshold speed at which the fluid film becomes unstable depends on the wave amplitude and on the supply pocket pressure. Even if the fluid film is unstable, the wave bearing maintains the whirl orbit inside the bearing clearance.

  4. Optimum array design to maximize Fisher information for bearing estimation.

    Tuladhar, Saurav R; Buck, John R


    Source bearing estimation is a common application of linear sensor arrays. The Cramer-Rao bound (CRB) sets a lower bound on the achievable mean square error (MSE) of any unbiased bearing estimate. In the spatially white noise case, the CRB is minimized by placing half of the sensors at each end of the array. However, many realistic ocean environments have a mixture of both white noise and spatially correlated noise. In shallow water environments, the correlated ambient noise can be modeled as cylindrically isotropic. This research designs a fixed aperture linear array to maximize the bearing Fisher information (FI) under these noise conditions. The FI is the inverse of the CRB, so maximizing the FI minimizes the CRB. The elements of the optimum array are located closer to the array ends than uniform spacing, but are not as extreme as in the white noise case. The optimum array results from a trade off between maximizing the array bearing sensitivity and minimizing output noise power variation over the bearing. Depending on the source bearing, the resulting improvement in MSE performance of the optimized array over a uniform array is equivalent to a gain of 2-5 dB in input signal-to-noise ratio. PMID:22087908

  5. Bearing Strengths of Some Wrought-aluminum Alloys

    Moore, R L; Wescoat, C


    Although a number of investigations of the bearing strength of aluminum alloys have been made, the problem remains one of considerable interest to the aircraft industry. For this reason it has seemed advisable to make additional tests of the commonly used aircraft alloys in an effort to establish a better basis for the selection of allowable bearing values. Current design practice does not recognize the effect of edge distance upon bearing strengths, and for this reason edge distance was one of the principal variables considered in this investigation. The increasing emphasis being placed upon permanent set limitations makes it essential that more information on bearing yield phenomena be obtained. The object of this investigation was to determine bearing yield and ultimate strengths of the following aluminum alloy products: 17S-T, 24S-T, Alclad 24S-T, 24S-RT, 52S-0, 52S-1/2H, 52S-H, 53S-T, and 61S-T extrusions. Ratios of these bearing properties to tensile properties were also determined.

  6. Mixed-mu superconducting bearings

    Hull, John R.; Mulcahy, Thomas M.


    A mixed-mu superconducting bearing including a ferrite structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet structure. The ferrite structure is levitated by said stationary permanent magnet structure.

  7. Microstructural and seismic properties of the upper mantle underneath a rifted continental terrane (Baja California): An example of sub-crustal mechanical asthenosphere?

    Palasse, L.N.; Vissers, R.L.M.; Paulssen, H.; Basu, A.R.; Drury, M.R.


    The Gulf of California rift is a young and active plate boundary that links the San Andreas strike-slip fault system in California to the oceanic spreading system of the East Pacific Rise. The xenolith bearing lavas of the San Quintin volcanic area provide lower crust and upper mantle samples from b

  8. The Immigrant University: Assessing the Dynamics of Race, Major and Socioeconomic Characteristics at the University of California

    Douglass, John Aubrey; Heinke Roebken; Thomson, Gregg


    The University of California has long been a major source of socioeconomic mobility in California. Data from the University of California’s Undergraduate Experience Survey (UCUES) indicates that more than half the undergraduate students in the UC system have at least one parent that is an immigrant. The ratio is even higher at UC Berkeley. What do such a high percentage of students with recent immigrant backgrounds tell us about the University of California and socioeconomic mobility? How i...

  9. Nonlinear Control of Magnetic Bearings

    Khac Duc Do; Dang Hoe Nguyen; Thanh Binh Nguyen


    In this paper, recent results controling nonlinear systems with output tracking error constraints are applied to the design of new tracking controllers for magnetic bearings. The proposed controllers can force the rotor to track a bounded and sufficiently smooth refer-ence trajectory asymptotically and guarantee non-contactedness be-tween the rotor and the stator of the magnetic bearings. Simulation results are included to illustrate the effectiveness of the proposed con-trollers.

  10. Failure analysis of superconducting bearings

    Rastogi, Amit; Campbell, A M; Coombs, T A [Department of Engineering, University of Cambridge, Cambridge CB2 1PZ (United Kingdom)


    The dynamics of superconductor bearings in a cryogenic failure scenario have been analyzed. As the superconductor warms up, the rotor goes through multiple resonance frequencies, begins to slow down and finally touches down when the superconductor goes through its transition temperature. The bearing can be modelled as a system of springs with axial, radial and cross stiffness. These springs go through various resonant modes as the temperature of the superconductor begins to rise. We have presented possible explanations for such behavio0008.

  11. Failure analysis of superconducting bearings

    The dynamics of superconductor bearings in a cryogenic failure scenario have been analyzed. As the superconductor warms up, the rotor goes through multiple resonance frequencies, begins to slow down and finally touches down when the superconductor goes through its transition temperature. The bearing can be modelled as a system of springs with axial, radial and cross stiffness. These springs go through various resonant modes as the temperature of the superconductor begins to rise. We have presented possible explanations for such behaviour

  12. Experimental study of tilting-pad journal bearings - Comparison with theoretical thermoelastohydrodynamic results

    Fillon, Michel; Bligoud, Jean-Claude; Frene, Jean


    Operating characteristics of four-shoe tilting-pad journal bearings of 100 mm diameter and 70 mm length are determined on an experimental device. The load, between pad configuration, varies from 0 to 10,000 N and the rotational speed is up to 4000 rpm. Forty thermocouples are used in order to measure bearing element temperatures (babbitt, shaft, housing and oil baths). The influence of operating conditions and preload ratio on bearing performances are studied. Comparison between theoretical and experimental results is presented. The theoretical model is also performed on a large tilting-pad journal bearing which was investigated experimentally by other authors.

  13. A study on compliant layers and its influence on dynamic response of a hydrodynamic journal bearing

    Thomsen, Kim; Klit, Peder


    For some hydrodynamic bearing applications polymer-lined bearings are chosen over traditional metal alloy bearings due to their better wear and friction properties when operating at very thin films, e.g. in the mixed lubrication region. The introduction of a compliant layer also affects the dynamic...... used to evaluate hydrodynamic bearing designs: dynamic response, maximum pressure, minimum film thickness, wear, power loss and temperature response. The primary findings are that the maximum pressures are reduced significantly and this comes at the expense of slightly higher eccentricity ratios during...

  14. California Data Exchange Center

    ... to make July &28;Water Smart Month.&29; &28;Conserving ... Remote sensors today indicate that statewide, snowpack water content is 54 percent of ... California ranked first, along with Texas, on ...

  15. Earthquakes in Southern California

    National Oceanic and Atmospheric Administration, Department of Commerce — There have been many earthquake occurrences in Southern California. This set of slides shows earthquake damage from the following events: Imperial Valley, 1979,...

  16. Coastal California Digital Imagery

    National Oceanic and Atmospheric Administration, Department of Commerce — This digital ortho-imagery dataset is a survey of coastal California. The project area consists of approximately 3774 square miles. The project design of the...

  17. California Ocean Uses Atlas

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is a result of the California Ocean Uses Atlas Project: a collaboration between NOAA's National Marine Protected Areas Center and Marine Conservation...

  18. Kelp distribution off California

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set delineates kelp beds (Nereocystis leutkeana and Macrocystis spp.) along the Pacific Coast of California. Multiple years of kelp mapping data for the...

  19. California Harpoon Fishery

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vessel logbook and landings data from harpoon vessels that fish within 200 miles of the California coast, from 1974 to present. The harpoon...

  20. California Watershed Hydrologic Units

    California Department of Resources — This dataset is intended to be used as a tool for water-resource management and planning activities, particularly for site-specific and localized studies requiring...

  1. Designing Rolling-Element Bearings

    Moore, James D., Jr.


    Bearing Analysis Tool (BAT) is a computer program for designing rolling-element bearings for cryogenic turbomachines. BAT provides a graphical user interface (GUI) that guides the entry of data to develop mathematical models of bearings. The GUI breaks model data into logical subsets that are entered through logic-driven input screens. The software generates a threedimensional graphical model of a bearing as the data are entered. Most dataentry errors become immediately obvious in the graphical model. BAT provides for storage of all the data on a shaft/bearing system, enabling the creation of a library of proven designs. Data from the library can be transferred to subsequent projects by use of simple cut-and-paste routines. BAT includes a library of temperature- dependent cryogenic bearing-material properties for use in the mathematical models. BAT implements algorithms that (1) enable the user to select combinations of design and/or operating-condition parameters, and then (2) automatically optimize the design by performing trade studies over all of the parameter combinations. This feature enables optimization over a large trade space in a fraction of the time taken when using prior bearingmodel software.

  2. Ultimate Bearing Strength of Post-tensioned Local Anchorage Zones in Lightweight Concrete

    Axson, Daniel Peter


    Currently, NCHRP Report 356 has published an equation to estimate the ultimate strength of the local zone in normal weight concrete. The local zone is the area of concrete directly ahead of the bearing plate. The equation can be broken into two distinct parts: unconfined bearing strength of concrete enhanced by the A/Ab ratio and the enhancement of strength due to the presence of confining. Research has shown that the strength enhancement of the A/Ab ratio and confining reinfor...

  3. Analysis of Two-Layered Journal Bearing Lubricated with Ferrofluid

    Rao T. V. V. L. N.


    Full Text Available The present study investigates the load capacity and friction coefficient for a two-layered journal bearing lubricated with ferrofluid. A modified Reynolds equation for a two-layered ferrofluid is derived using displaced infinitely long wire magnetic field model. Reynolds boundary conditions are used to obtain nondimensional pressure and shear stress expressions. Nondimensional load capacity and coefficient of friction are analyzed under the influence of lubricant layer’s thickness, viscosities, magnetic field intensity and distance ratio parameter. Ferrofluid lubrication under the influence of magnetic field has potential to enhance load carrying capacity and reduce coefficient of friction for two-layered journal bearing.

  4. 77 FR 70423 - Black Bear Hydro Partners, LLC and Black Bear Development Holdings, LLC and Black Bear SO, LLC...


    ... Energy Regulatory Commission Black Bear Hydro Partners, LLC and Black Bear Development Holdings, LLC and Black Bear SO, LLC; Notice of Application for Partial Transfer of Licenses, and Soliciting Comments and Motions To Intervene On October 25, 2012, Black Bear Hydro Partners, LLC, sole licensee (transferor)...

  5. Salmon-Eating Grizzly Bears Exposed to Elevated Levels of Marine Derived Persistent Organic Pollutants

    Christensen, J. R.; Ross, P. S.; Whiticar, M. J.


    The coastal grizzly bears of British Columbia (BC, Canada) rely heavily on salmon returning from the Pacific Ocean, whereas interior bears do not have access to or readily utilize this marine-derived food source. Since salmon have been shown to accumulate persistent organic pollutants (POPs) from the North Pacific Ocean, we hypothesized that salmon consumption by grizzly bears would be reflected by an increase in the POP burden. To test this hypothesis we collected hair and fat tissue from grizzlies at various locations around BC to compare salmon-eating (coastal) grizzlies to non-salmon-eating (interior) grizzlies. We characterized the feeding habits for each bear sampled by measuring the stable carbon and nitrogen isotope signature of their hair. The positive relationship between 13C/12C and 15N/14N isotopic ratios suggests that the majority of the meat portion of the diet of coastal grizzlies is coming from salmon, rather than from terrestrial or freshwater sources. By contrast, stable isotope ratios revealed that interior bears have an almost exclusive vegetarian diet with no marine influence. As hypothesized, the coastal grizzly bears have significantly greater OC pesticide and lower-brominated PBDE congener body burden than the interior grizzlies. We also found a positive relationship between C and N isotope ratios and these same POP contaminants in bear tissue. Overall, these results demonstrate that Pacific salmon represents a significant vector delivering both OC pesticides and PBDEs to BC coastal grizzly bears.

  6. Fatigue analysis of wind turbine gearbox bearings using SCADA data and miner's rule

    Long, H.; J. Wu; Matthew, F.; Tavner, P.


    This paper presents studies of wind turbine load estimation, based upon SCADA data, to derive bearing load histograms for the high speed shaft (HSS) of a typical, three-stage, wind turbine gearbox. Rain-flow counting has been applied to determine the number of loading occurrences at different load values. Damage ratios for bearings have been predicted using this data by the application of Miner's rule. Results show that the bearings have an overload Cycle Ratio of less than 20% above rated an...

  7. Bear reintroduction: Lessons and challenges

    Clark, Joseph D.; Huber, Djuro; Servheen, Christopher


    Reintroduction is defined as an attempt to establish a species in an area that was once part of its historical range, but from which it has been extirpated or become extinct. Historically, one of the most successful programs was the reintroduction of 254 American black bears (Ursus americanus) from Minnesota to the Interior Highlands of Arkansas in the 1960s; that population has grown to >2,500 today. More recent efforts have involved fewer but better monitored animals and have sometimes employed techniques to improve site fidelity and survival. In Pennsylvania, for example, pregnant female American black bears were successfully translocated from winter dens, the premise being that the adult females would be less likely to return because of the presence of young cubs. That winter-release technique was compared to summer trapping and release in Tennessee; winter releases resulted in greater survival and reduced post-release movements. Homing has not been a problem for small numbers of brown bears (Ursus arctos) reintroduced to the Cabinet-Yaak ecosystem in Montana and Idaho and to the mountains of Austria and France. Reintroduction success appears to be correlated with translocation distance and is greater for subadults and females. As with any small population, reintroduced bear populations are susceptible to environmental variation and stochastic demographic and genetic processes. Although managers have focused on these biological barriers, sociopolitical impediments to bear reintroduction are more difficult to overcome. Poor public acceptance and understanding of bears are the main reasons some reintroduction programs have been derailed. Consequently, the public should be involved in the reintroduction process from the outset; overcoming negative public perceptions about bear reintroduction will be our greatest challenge.

  8. 49 CFR 229.69 - Side bearings.


    ... 49 Transportation 4 2010-10-01 2010-10-01 false Side bearings. 229.69 Section 229.69....69 Side bearings. (a) Friction side bearings with springs designed to carry weight may not have more than 25 percent of the springs in any one nest broken. (b) Friction side bearings may not be run...

  9. 36 CFR 13.1236 - Bear orientation.


    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Bear orientation. 13.1236... Developed Area § 13.1236 Bear orientation. All persons visiting the BCDA must receive an NPS-approved Bear Orientation. Failure to receive an NPS-approved Bear Orientation is prohibited....

  10. Superconductor bearings, flywheels and transportation

    Werfel, F. N.; Floegel-Delor, U.; Rothfeld, R.; Riedel, T.; Goebel, B.; Wippich, D.; Schirrmeister, P.


    This paper describes the present status of high temperature superconductors (HTS) and of bulk superconducting magnet devices, their use in bearings, in flywheel energy storage systems (FESS) and linear transport magnetic levitation (Maglev) systems. We report and review the concepts of multi-seeded REBCO bulk superconductor fabrication. The multi-grain bulks increase the averaged trapped magnetic flux density up to 40% compared to single-grain assembly in large-scale applications. HTS magnetic bearings with permanent magnet (PM) excitation were studied and scaled up to maximum forces of 10 kN axially and 4.5 kN radially. We examine the technology of the high-gradient magnetic bearing concept and verify it experimentally. A large HTS bearing is tested for stabilizing a 600 kg rotor of a 5 kWh/250 kW flywheel system. The flywheel rotor tests show the requirement for additional damping. Our compact flywheel system is compared with similar HTS-FESS projects. A small-scale compact YBCO bearing with in situ Stirling cryocooler is constructed and investigated for mobile applications. Next we show a successfully developed modular linear Maglev system for magnetic train operation. Each module levitates 0.25t at 10 mm distance during one-day operation without refilling LN2. More than 30 vacuum cryostats containing multi-seeded YBCO blocks are fabricated and are tested now in Germany, China and Brazil.

  11. Superconductor bearings, flywheels and transportation

    This paper describes the present status of high temperature superconductors (HTS) and of bulk superconducting magnet devices, their use in bearings, in flywheel energy storage systems (FESS) and linear transport magnetic levitation (Maglev) systems. We report and review the concepts of multi-seeded REBCO bulk superconductor fabrication. The multi-grain bulks increase the averaged trapped magnetic flux density up to 40% compared to single-grain assembly in large-scale applications. HTS magnetic bearings with permanent magnet (PM) excitation were studied and scaled up to maximum forces of 10 kN axially and 4.5 kN radially. We examine the technology of the high-gradient magnetic bearing concept and verify it experimentally. A large HTS bearing is tested for stabilizing a 600 kg rotor of a 5 kWh/250 kW flywheel system. The flywheel rotor tests show the requirement for additional damping. Our compact flywheel system is compared with similar HTS–FESS projects. A small-scale compact YBCO bearing with in situ Stirling cryocooler is constructed and investigated for mobile applications. Next we show a successfully developed modular linear Maglev system for magnetic train operation. Each module levitates 0.25t at 10 mm distance during one-day operation without refilling LN2. More than 30 vacuum cryostats containing multi-seeded YBCO blocks are fabricated and are tested now in Germany, China and Brazil.

  12. Future Bearing Surfaces in Total Hip Arthroplasty

    Chang, Jun-Dong


    One of the most important issues in the modern total hip arthroplasty (THA) is the bearing surface. Extensive research on bearing surfaces is being conducted to seek an ideal bearing surface for THA. The ideal bearing surface for THA should have superior wear characteristics and should be durable, bio-inert, cost-effective, and easy to implant. However, bearing surfaces that are currently being implemented do not completely fulfill these requirements, especially for young individuals for whom...

  13. Geologic quadrangle maps of the United States: geology of the Casa Diablo Mountain quadrangle, California

    Rinehart, C. Dean; Ross, Donald Clarence


    The Casa Diablo Mountain quadrangle was mapped in the summers of 1952 and 1953 by the U.S. Geological Survey in cooperation with the California State Division of Mines as part of a study of potential tungsten-bearing areas.

  14. The California Hazards Institute

    Rundle, J. B.; Kellogg, L. H.; Turcotte, D. L.


    California's abundant resources are linked with its natural hazards. Earthquakes, landslides, wildfires, floods, tsunamis, volcanic eruptions, severe storms, fires, and droughts afflict the state regularly. These events have the potential to become great disasters, like the San Francisco earthquake and fire of 1906, that overwhelm the capacity of society to respond. At such times, the fabric of civic life is frayed, political leadership is tested, economic losses can dwarf available resources, and full recovery can take decades. A patchwork of Federal, state and local programs are in place to address individual hazards, but California lacks effective coordination to forecast, prevent, prepare for, mitigate, respond to, and recover from, the harmful effects of natural disasters. Moreover, we do not know enough about the frequency, size, time, or locations where they may strike, nor about how the natural environment and man-made structures would respond. As California's population grows and becomes more interdependent, even moderate events have the potential to trigger catastrophes. Natural hazards need not become natural disasters if they are addressed proactively and effectively, rather than reactively. The University of California, with 10 campuses distributed across the state, has world-class faculty and students engaged in research and education in all fields of direct relevance to hazards. For that reason, the UC can become a world leader in anticipating and managing natural hazards in order to prevent loss of life and property and degradation of environmental quality. The University of California, Office of the President, has therefore established a new system-wide Multicampus Research Project, the California Hazards Institute (CHI), as a mechanism to research innovative, effective solutions for California. The CHI will build on the rich intellectual capital and expertise of the Golden State to provide the best available science, knowledge and tools for

  15. Financial Key Ratios

    Tănase Alin-Eliodor


    This article focuses on computing techniques starting from trial balance data regarding financial key ratios. There are presented activity, liquidity, solvency and profitability financial key ratios. It is presented a computing methodology in three steps based on a trial balance.

  16. Shape memory alloy wire-based smart natural rubber bearing

    In this study, two types of smart elastomeric bearings are presented using shape memory alloy (SMA) wires. Due to the unique characteristics of SMAs, such as the superelastic effect and the recentering capability, the residual deformation in SMA-based natural rubber bearings (SMA-NRBs) is significantly reduced whereas the energy dissipation capacity is increased. Two different configurations of SMA wires incorporated in elastomeric bearings are considered. The effect of several parameters, including the shear strain amplitude, the type of SMA, the aspect ratio of the base isolator, the thickness of SMA wire, and the amount of pre-strain in the wires on the performance of SMA-NRBs is investigated. Rubber bearings are composed of natural rubber layers bonded to steel shims as reinforcement. Results show that ferrous SMA wire, FeNiCuAlTaB, with 13.5% superelastic strain and a very low austenite finish temperature (−62 °C), is the best candidate to be used in SMA-NRBs subjected to high shear strain amplitudes. In terms of the lateral flexibility and wire strain level, the smart rubber bearing with a cross configuration of SMA wires is more efficient. Moreover, the cross configuration can be implemented in high-aspect-ratio elastomeric bearings since the strain induced in the wire does not exceed the superelastic range. When cross SMA wires with 2% pre-strain are used in a smart NRB, the dissipated energy is increased by 74% and the residual deformation is decreased by 15%. (paper)

  17. 'Dodo' and 'Baby Bear' Trenches


    NASA's Phoenix Mars Lander's Surface Stereo Imager took this image on Sol 11 (June 5, 2008), the eleventh day after landing. It shows the trenches dug by Phoenix's Robotic Arm. The trench on the left is informally called 'Dodo' and was dug as a test. The trench on the right is informally called 'Baby Bear.' The sample dug from Baby Bear will be delivered to the Phoenix's Thermal and Evolved-Gas Analyzer, or TEGA. The Baby Bear trench is 9 centimeters (3.1 inches) wide and 4 centimeters (1.6 inches) deep. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  18. The Story of California = La Historia de California.

    Bartel, Nick

    "The Story of California" is a history and geography of the state of California, intended for classroom use by limited-English-proficient, native Spanish-speaking students in California's urban middle schools. The book is designed with the left page in English and the right page in Spanish to facilitate student transition into comfortable use of…

  19. Quantitative Diagnosis of Fault Severity Trend of Rolling Element Bearings

    CUI Lingli; MA Chunqing; ZHANG Feibin; WANG Huaqing


    The condition monitoring and fault diagnosis of rolling element bearings are particularly crucial in rotating mechanical applications in industry. A bearing fault signal contains information not only about fault condition and fault type but also the severity of the fault. This means fault severity quantitative analysis is one of most active and valid ways to realize proper maintenance decision. Aiming at the deficiency of the research in bearing single point pitting fault quantitative diagnosis, a new back-propagation neural network method based on wavelet packet decomposition coefficient entropy is proposed. The three levels of wavelet packet coefficient entropy(WPCE) is introduced as a characteristic input vector to the BPNN. Compared with the wavelet packet decomposition energy ratio input vector, WPCE shows more sensitive in distinguishing from the different fault severity degree of the measured signal. The engineering application results show that the quantitative trend fault diagnosis is realized in the different fault degree of the single point bearing pitting fault. The breakthrough attempt from quantitative to qualitative on the pattern recognition of rolling element bearings fault diagnosis is realized.

  20. Quantitative diagnosis of fault severity trend of rolling element bearings

    Cui, Lingli; Ma, Chunqing; Zhang, Feibin; Wang, Huaqing


    The condition monitoring and fault diagnosis of rolling element bearings are particularly crucial in rotating mechanical applications in industry. A bearing fault signal contains information not only about fault condition and fault type but also the severity of the fault. This means fault severity quantitative analysis is one of most active and valid ways to realize proper maintenance decision. Aiming at the deficiency of the research in bearing single point pitting fault quantitative diagnosis, a new back-propagation neural network method based on wavelet packet decomposition coefficient entropy is proposed. The three levels of wavelet packet coefficient entropy(WPCE) is introduced as a characteristic input vector to the BPNN. Compared with the wavelet packet decomposition energy ratio input vector, WPCE shows more sensitive in distinguishing from the different fault severity degree of the measured signal. The engineering application results show that the quantitative trend fault diagnosis is realized in the different fault degree of the single point bearing pitting fault. The breakthrough attempt from quantitative to qualitative on the pattern recognition of rolling element bearings fault diagnosis is realized.

  1. California's Future Carbon Flux

    Xu, L.; Pyles, R. D.; Paw U, K.; Gertz, M.


    The diversity of the climate and vegetation systems in the state of California provides a unique opportunity to study carton dioxide exchange between the terrestrial biosphere and the atmosphere. In order to accurately calculate the carbon flux, this study couples the sophisticated analytical surface layer model ACASA (Advance Canopy-Atmosphere-Soil Algorithm, developed in the University of California, Davis) with the newest version of mesoscale model WRF (the Weather Research & Forecasting Model, developed by NCAR and several other agencies). As a multilayer, steady state model, ACASA incorporates higher-order representations of vertical temperature variations, CO2 concentration, radiation, wind speed, turbulent statistics, and plant physiology. The WRF-ACASA coupling is designed to identify how multiple environmental factors, in particularly climate variability, population density, and vegetation distribution, impact on future carbon cycle prediction across a wide geographical range such as in California.

  2. Trends in Controllable Oil Film Bearings

    Santos, Ilmar


    This work gives an overview about the theoretical and experimental achievements of mechatronics applied to oil film bearings, with the aim of: controlling the lateral vibration of flexible rotating shafts; modifying bearing dynamic characteristics, as stiffness and damping properties; increasing .......e., as tilting-pad bearings, multirecess journal bearings and plain bearings.......This work gives an overview about the theoretical and experimental achievements of mechatronics applied to oil film bearings, with the aim of: controlling the lateral vibration of flexible rotating shafts; modifying bearing dynamic characteristics, as stiffness and damping properties; increasing...... the rotational speed ranges by improving damping and eliminating instability problems, for example, by compensating cross-coupling destabilizing effects; reducing startup torque and energy dissipation in bearings; compensating thermal effects. It is shown that such controllable bearings can act as...

  3. California Indian Food and Culture.


    This learning kit begins with a glossary of terms to help students learn about California Indians and their food. The kit explains that California Indians were the first people to live in the area now known as California, and that these tribes differed in the languages they spoke, the regions they lived in, and the foods that they ate. It explains…


    Jarosław KACZOR


    Full Text Available Durability deep groove ball bearings depends on factors (called attributes design, technological and operational. Among the design features one of the most important is play in the bearings. Polish Norm shows five groups of looseness in the bearings, in which the play range from 0 to 105 microns. Manufacturers of rolling bearings they only play group, which has a bearing data, without giving the exact value of the slack. Aim of this study is to determine how it affects the play in the bearings to work three-bearing shafts, including elasticity and resilience three-bearing shafts.

  5. Steady-state and transient analysis of a squeeze film damper bearing for rotor stability

    Barrett, L. E.; Gunter, E. J.


    A study of the steady-state and transient response of the squeeze film damper bearing is presented. Both the steady-state and transient equations for the hydrodynamic bearing forces are derived. The bearing equivalent stiffness and damping coefficients are determined by steady-state equations. These coefficients are used to find the bearing configuration which will provide the optimum support characteristics based on a stability analysis of the rotor-bearing system. The transient analysis of rotor-bearing systems is performed by coupling the bearing and journal equations and integrating forward in time. The effects of unbalance, cavitation, and retainer springs are included in the analysis. Methods of determining the stability of a rotor-bearing system under the influence of aerodynamic forces and internal shaft friction are discussed with emphasis on solving the system characteristic frequency equation and on producing stability maps. It is shown that for optimum stability and low force transmissability the squeeze bearing should operate at an eccentricity ratio epsilon 0.4.


    Duffield, Wendell A.; Weldin, Robert E.


    A mineral appraisal utilized geologic, geochemical, and geophysical data and an examination of mining claims in the South Warner Wilderness, California. Results of this study indicate that little promise for the occurrence of mineral resources exists within the area. Small veins of optical quality calcite occur on the east side of the area but, are not considered a resource.

  7. WWER-1000 dominance ratio

    Dominance ratio, or more precisely, its closeness to unity, is important characteristic of large reactor. It allows evaluate beforehand the number of source iterations required in deterministic calculations of power spatial distribution. Or the minimal number of histories to be modeled for achievement of statistical error level desired in large core Monte Carlo calculations. In this work relatively simple approach for dominance ratio evaluation is proposed. It essentially uses core symmetry. Dependence of dominance ratio on neutron flux spatial distribution is demonstrated. (Authors)

  8. VVER-1000 dominance ratio

    Dominance ratio, or more precisely, its closeness to unity, is important characteristic of large reactor. It allows evaluate beforehand the number of source iterations required in deterministic calculations of power spatial distribution. Or the minimal number of histories to be modeled for achievement of statistical error level desired in large core Monte Carlo calculations. In this work relatively simple approach for dominance ratio evaluation is proposed. It essentially uses core symmetry. Dependence of dominance ratio on neutron flux spatial distribution is demonstrated. (author)

  9. Journal and Wave Bearing Impedance Calculation Software

    Hanford, Amanda; Campbell, Robert


    The wave bearing software suite is a MALTA application that computes bearing properties for user-specified wave bearing conditions, as well as plain journal bearings. Wave bearings are fluid film journal bearings with multi-lobed wave patterns around the circumference of the bearing surface. In this software suite, the dynamic coefficients are outputted in a way for easy implementation in a finite element model used in rotor dynamics analysis. The software has a graphical user interface (GUI) for inputting bearing geometry parameters, and uses MATLAB s structure interface for ease of interpreting data. This innovation was developed to provide the stiffness and damping components of wave bearing impedances. The computational method for computing bearing coefficients was originally designed for plain journal bearings and tilting pad bearings. Modifications to include a wave bearing profile consisted of changing the film thickness profile given by an equation, and writing an algorithm to locate the integration limits for each fluid region. Careful consideration was needed to implement the correct integration limits while computing the dynamic coefficients, depending on the form of the input/output variables specified in the algorithm.

  10. Mobile bearing and fixed bearing total knee arthroplasty

    Dolfin, Marco; Saccia, Francesco


    The mobile bearing (MB) concept in total knee arthroplasty (TKA) was developed as an alternative to fixed bearing (FB) implants in order to reduce wear and improve range of motion (ROM), especially focused on younger patients. Unfortunately, its theoretical advantages are still controversial. In this paper we exhibit a review of the more recent literature available comparing FB and MB designs in biomechanical and clinical aspects, including observational studies, clinical trials, national and international registries analyses, randomized controlled trials, meta-analyses and Cochrane reviews. Except for some minor aspects, none of the studies published so far has reported a significant improvement related to MBs regarding patient satisfaction, clinical, functional and radiological outcome or medium and long-term survivorship. Thus the presumed superiority of MBs over FBs appears largely inconsistent. The routine use of MB is not currently supported by adequate evidences; implant choice should be therefore made on the basis of other factors, including cost and surgeon experience. PMID:27162777

  11. Effects of bearing deadbands on bearing loads and rotor stability


    A generic model of a turbopump, simplified to bring out these effects is examined. This model demonstrates that bearing deadbands which are of the same order of magnitude or larger than the center-of-mass offset of a rotor due to mass imbalances cause significantly different dynamic behavior than would be expected of a linear, dynamical system. This fundamentally nonlinear behavior yields altered stability characteristics and altered bearing loading tendencies. It is shown that side forces can enhance system stability in the small, i.e., as long as the mass imbalance does not exceed some thresholds value or as long as no large, impulsive disturbances cause the motion to depart significantly from the region of stability. Limit cycles are investigated in this report and techniques for determining these limit cycles are developed. These limit cycles are the major source of bearing loading and appear in both synchronous and nonsynchronous forms. The synchronous limit cycles are driven by rotor imbalances. The nonsynchronous limit cycles (also called subsynchronous whirls) are self-excited and are the sources of instability.

  12. Live-trapping and handling brown bear

    US Fish and Wildlife Service, Department of the Interior — This paper reports techniques developed to live trap and handle brown bears on the Kodiak National Wildlife Refuge. The brown bears (Ursus middendorffi) on the...

  13. Brown bear telemetry and trapping: Special report

    US Fish and Wildlife Service, Department of the Interior — Brown bear studies were continued during the 1967 field season with emphasis on development of techniques for instrumenting bears with radio transmitters and...

  14. Goose Eggs Could Save Polar Bears



    Polar bears could avoid extinction despitemany starving to death in coming years, ac-cording to scientists and other observers whohave discovered that some of the bears havefound a new food source--goose and duckeggs.

  15. Shaft Center Orbit in Dynamically Loaded Bearings

    Klit, Peder

    The aim of this work is to demonstrate how to utilize the bearings damping coefficients to estimate the orbit for a dynamically loaded journal bearing. The classical method for this analysis was developed by Booker in 1965 and described further in 1972. Several authors have refined this method over...... the years. In 1966 Jorgen W. Lund published an approach to find the dynamic coefficients of a journal bearing by a first order perturbation of the Reynold's equation. These coefficients made it possible to perform a rotor-bearing stability analysis for a statically loaded bearing. In the mid seventies...... Jorgen W. Lund pointed out in lecture notes that the dynamic damping coefficients of the bearing could be used to find the shaft orbit for dynamically loaded bearings. For simplicity the "Short-Width-Journal-Bearing Theory" is used as a basis for finding the damping coefficients in this work, but the...

  16. Detecting isotopic ratio outliers

    An alternative method is proposed for improving isotopic ratio estimates. This method mathematically models pulse-count data and uses iterative reweighted Poisson regression to estimate model parameters to calculate the isotopic ratios. This computer-oriented approach provides theoretically better methods than conventional techniques to establish error limits and to identify outliers. 6 refs., 3 figs., 3 tabs

  17. Reducing friction in tilting-pad bearings by the use of enclosed recesses

    Heinrichson, Niels; Santos, Ilmar


    A three-dimensional thermoelastohydrodynamic model is applied to the analysis of tilting-pad bearings with spherical pivots and equipped with deep recesses in the high-pressure regions. A potential for a 10-20% reduction in the friction loss compared to conventional plain bearing pads is documented....... Design suggestions minimizing the power loss are given for various length-to-width ratios. The tilting angle in the sliding direction is more sensitive to correct positioning of the pivot point than conventional bearing pads. Improving the performance by equipping a tilting-pad bearing with a deep recess...... therefore requires accurate analysis and design of the bearing. Similarly, a high sensitivity perpendicular to the sliding direction suggests that this method of reducing friction is more feasible when using line pivots or spring beds than when using spherical pivots for controlling the tilting angle....

  18. Oil film pressure in hydrodynamic journal bearings

    Valkonen, Antti


    Hydrodynamic journal bearings are critical power transmission components that are carrying increasingly high loads because of the increasing power density in various machines. Therefore, knowing the true operating conditions of hydrodynamic journal bearings is essential to machine design. Oil film pressure is one of the key operating parameters describing the operating conditions in hydrodynamic journal bearings. Measuring the oil film pressure in bearings has been a demanding task and theref...

  19. Mercury in polar bears from Alaska

    Lentfer, J.W.; Galster, W.A.


    Alaskan polar bear (Ursus maritimus) muscle and liver samples collected in 1972 were analyzed for total mercury. Bears north of Alaska had more mercury than bears west of Alaska. The only difference between young and adult animals was in the northern area where adults had more mercury in liver tissue than young animals. Levels were probably not high enough to be a serious threat to bears.

  20. Technology development for indigenous water lubricated bearings

    Water Lubricated Bearings (WLB) are used in various mechanisms of fuel handling systems of PHWRs and AHWR. Availability and random failures of these bearings was a major factor in refuelling operations. Indigenous development of these bearings was taken up and 7 types of antifriction bearings in various sizes (totaling 37 variants) for PHWR, AHWR and Dhruva applications were successfully developed. This paper deals with various aspects of WLB development. (author)

  1. Thin film superconductor magnetic bearings

    Weinberger, Bernard R.


    A superconductor magnetic bearing includes a shaft (10) that is subject to a load (L) and rotatable around an axis of rotation, a magnet (12) mounted to the shaft, and a stator (14) in proximity to the shaft. The stator (14) has a superconductor thin film assembly (16) positioned to interact with the magnet (12) to produce a levitation force on the shaft (10) that supports the load (L). The thin film assembly (16) includes at least two superconductor thin films (18) and at least one substrate (20). Each thin film (18) is positioned on a substrate (20) and all the thin films are positioned such that an applied magnetic field from the magnet (12) passes through all the thin films. A similar bearing in which the thin film assembly (16) is mounted on the shaft (10) and the magnet (12) is part of the stator (14) also can be constructed.

  2. 49 CFR 229.64 - Plain bearings.


    ... 49 Transportation 4 2010-10-01 2010-10-01 false Plain bearings. 229.64 Section 229.64 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION....64 Plain bearings. A plain bearing box shall contain visible free oil and may not be cracked to...

  3. Passive Thermal Management of Foil Bearings

    Bruckner, Robert J. (Inventor)


    Systems and methods for passive thermal management of foil bearing systems are disclosed herein. The flow of the hydrodynamic film across the surface of bearing compliant foils may be disrupted to provide passive cooling and to improve the performance and reliability of the foil bearing system.

  4. Hazards within the Bear Lake basin, Utah

    Palacios, Patsy; Luecke, Chris; Robinson, Justin


    The Bear Lake basin developed from fault subsidence that continues today, slowly deepening the lake along the eastern side. The Bear Lake graben is about 5 miles long and 4.3-8.6 miles wide. It extends across the Utah-Idaho border and involves faults on both eastern and western sides of Bear Lake....

  5. Virginia Tech Bear Researchers Ensure Populations

    Davis, Lynn


    The Cooperative Alleghany Bear Study (CABS) was initiated in 1994 as a 10-year study to ensure survival of Virginia's hunted black bear population of western Virginia. During the first six years of the study, researchers have placed radio collars on 376 of the 746 bears captured.

  6. The vented pressure fed gas journal bearing

    Hydrodynamic-type gas journal bearings with stabilising venting slots are often operated hydrostatically during starting-up as a means of 'jacking'. A simplified mathematical treatment of the circumferential gas flows in a vented, pressure-fed journal bearing is used to predict the relationship between load capacity, bearing geometry and gas properties. (author)

  7. Cool Polar Bears: Dabbing on the Texture

    O'Connell, Jean


    In this article, the author describes how her second-graders created their cool polar bears. The students used the elements of shape and texture to create the bears. They used Monet's technique of dabbing paint so as to give the bear some texture on his fur.

  8. Fractal analysis of polar bear hairs

    Wang Qing-Li


    Full Text Available Hairs of a polar bear (Ursus maritimus are of superior properties such as the excellent thermal protection. Why do polar bears can resist such cold environment? The paper concludes that its fractal porosity plays an important role, and its fractal dimensions are very close to the golden mean, 1.618, revealing the possible optimal structure of polar bear hair.

  9. Steady State Performance Characteristics of a Single Pad Externally Adjustable Fluid Film Bearing

    Shenoy, Satish B.; Pai, Raghuvir

    The steady state performance characteristics of centrally loaded 60 degree single pad externally adjustable partial arc bearing is studied theoretically. Principal feature of the bearing is the facility to control its radial clearance and circumferential film thickness gradient, during operation. The bearing has aspect ratios of 1.0, 0.5 and 0.25 and operates over a wide range of eccentricity ratios and adjustments. Steady state performance characteristics of the bearing are presented in terms of attitude angle, load carrying capacity, oil flow and friction variable. The steady state form of Reynolds equation in two dimensions is solved numerically using the finite difference method. The effect of tilt and the radial adjustments on the steady state performance characteristics are presented in the form of plots. A comparative study predicts that negative radial and negative tilt adjustment results in better load carrying capacity with reduced oil flow and friction.

  10. Microstructural degradation of bearing steels

    Solano Alvarez, Wilberth


    The aim of the work presented in this thesis is to clarify one of the most fundamental aspects of fatigue damage in bearings steels through critical experiments, in particular whether damage in the form of cracks precedes hard ?white-etching matter" formation, which is carbon supersaturated nanoscaled ferrite. Heat treatments have been designed to create four different crack types and distributions: scarce martensite plate cracks, fine grain boundary cracks, abundant martensite plate cracks, ...

  11. Elid superfinishing of spherical bearings

    Raffles, Mark H.


    Driven by a requirement to extend the lifespan of self-aligning lined spherical bearings, this research investigates the use of Elid (electrolytic in-process dressing) as a method of improving ball surface finish. Elid is a continuous and self-regulating electrochemical dressing process that modifies the surface of a grinding, lapping, or superfinishing wheel. It provides improved grit protrusion, impedes wheel loading / glazing and promotes effective cutting. The characteri...

  12. Risk-bearing and Entrepreneurship

    Newman, Andrew


    In the 'Knightian' theory of entrepreneurship, entrepreneurs provide insurance to workers by paying fixed wages and bear all the risk of production. This paper endogenizes entrepreneurial risk by allowing for optimal insurance contracts as well as the occupational self-selection. Moral hazard prevents full insurance; increases in an agent’s wealth then entail increases in risk borne. Thus, even under decreasing risk aversion, there are robust instances in which workers are wealthier than entr...


    Andrzej RACZYŃSKI; Jarosław KACZOR


    Angular contact ball bearings are commonly used in such situations when you need to reach high bearing stiffness. However, a significant stiffness increase can be achieved only through the introduction of preload to the angular contact bearings. The purpose of this paper is to present a method for assessing the effect of preload of the angular contact bearings for their durability.


    Andrzej RACZYŃSKI


    Full Text Available Angular contact ball bearings are commonly used in such situations when you need to reach high bearing stiffness. However, a significant stiffness increase can be achieved only through the introduction of preload to the angular contact bearings. The purpose of this paper is to present a method for assessing the effect of preload of the angular contact bearings for their durability.

  15. Responses of Roadside Soil Cation Pools to Vehicular Emission Deposition in Southern California

    Rossi, R.; Bain, D. J.; Jenerette, D.; Clarke, L. W.; Wilson, K.


    Roadside soils are heavily loaded with NO3- due to vehicular emissions. This deposition likely acidifies these soils, potentially mobilizing cationic species from soil exchange sites. Acidification driven mobilization is well documented in forest soils, but poorly understood in roadside soils. Metal concentrations in park and garden soils collected from Southern California were examined across gradients of soil chemistry, road network density, climate, and geology to examine cation mobilization effects. In our samples, soil pH is not clearly related to distance from the roadside or underlying geology. However, the depletion of several elements (Al, K) is clearly observed in near-road environments. These depletion trends occur despite contrary trends, including increased soil surface areas and soil organic matter in near-road environments. Additionally, inputs from the weathering of road building materials appear to affect soil chemistry. For example, soil Ca patterns remain relatively consistent relative to roads, suggesting Ca bearing weathering products replenish soil Ca pools in near-road areas. Simple mixing models constructed using elemental ratios are consistent with road material Ca source contributions. Observed near-road patterns in soil chemistry likely influence local ecological function, shifting plant communities and soil functions. Clear understanding of these shifts is essential to the effective use of green infrastructure and other strategies utilized to control road-sourced nutrients. This analytical framework can be applied globally as road networks continue to expand and affect larger ecosystems.

  16. Deterrence and arrest ratios.

    Carmichael, Stephanie E; Piquero, Alex R


    In the limited research on the origins of sanction threat perceptions, researchers have focused on either the effects of actively engaging in crime or the effects of formal sanctioning but rarely on both (i.e., the arrest ratio or the number of arrests relative to the number of crimes committed). This article extends this line of research by using a sample of Colorado inmates and measures arrest ratios and sanction perceptions for eight different crime types. Analyses reveal that the offenders report both significant experiential and arrest ratio effects. Theoretical and policy implications, limitations, and directions for future research are outlined. PMID:16397123

  17. Sodium to phosphate ratios

    Phosphate chemistry is widely used in fossil-fired utility boilers and many of these phosphate programs use the sodium to phosphate ratio as the controlling parameter. This paper steps through the fundamental chemical analyses to determine a systems Na/PO4 ratio. A mathematical equation is introduced to simply calculate the ratio using the pH and phosphate concentration. This equation is also used to build graphs to chart the boiler's phosphate chemistry. By looking at the dynamic nature of the chemistry, boiler health can be determined. (orig.)

  18. Cannibalism and predation on black bears by grizzly bears in the Yellowstone ecosystem, 1975-1990

    Mattson, D.J.; Knight, R.R.; Blanchard, B.M.


    We documented one instance of an adult male grizzly bear preying upon a black bear and four instances where circumstantial evidence suggested that grizzly bears (two cubs-of-the-year, one yearling female that was injured, and one adult male) had been preyed upon by conspecifics. We also examined feces of grizzly bears for bear remains. Remains of bears tended to be more common in spring feces and did not differ in frequency between early and late years of the study. Our observations generally support existing hypotheses concerning cannibalism among bears.

  19. Ball Bearing Stacking Automation System

    Shafeequerrahman S . Ahmed


    Full Text Available This document is an effort to introduce the concept of automation in small scale industries and or small workshops that are involved in the manufacturing of small objects such as nuts, bolts and ball bearing in this case. This an electromechanical system which includes certain mechanical parts that involves one base stand on which one vertical metallic frame is mounted and hinged to this vertical stand is an in humanized effort seems inadequate in this era making necessary the use of Electronics, Computer in the manufacturing processes leading to the concept of Automated Manufacturing System (AMS.The ball bearing stack automation is an effort in this regard. In our project we go for stack automation for any object for example a ball bearing, be that is still a manual system there. It will be microcontroller based project control system equipped with microcontroller 89C51 from any manufacturer like Atmel or Philips. This could have been easily implemented if a PLC could be used for manufacturing the staking unit but I adopted the microcontroller based system so that some more modification in the system can be effected at will as to use the same hardware .Although a very small object i.e. ball bearig or small nut and fixture will be tried to be stacked, the system with more precision and more power handling capacity could be built for various requirements of the industry. For increasing more control capacity, we can use another module of this series. When the bearing is ready, it will be sent for packing. This is sensed by an inductive sensor. The output will be proceeds by PLC and microcontroller card which will be driving the assembly in order to put it into pads or flaps. This project will also count the total number of bearings to be packed and will display it on a LCD for real time reference and a provision is made using a higher level language using hyper terminal of the computer

  20. Steady State Performance Characteristics of Micropolar Lubricated Hydrodynamic Journal Bearings with Flexible Liner

    Bansal, Pikesh; Chattopadhyay, Ajit Kumar; Agrawal, Vishnu Prakash


    The aim of the present study is to theoretically determine the steady state characteristics of hydrodynamic oil journal bearings considering the effect of deformation of liner and with micropolar lubrication. Modified Reynolds equation based on micropolar lubrication theory is solved using finite difference method to obtain steady state film pressures. Minimum film thickness is calculated taking into consideration the deformation of the liner. Parametric study has been conducted and steady state characteristics for journal bearing with elasticity of bearing liner are plotted for various values of eccentricity ratio, deformation factor, characteristic length and coupling number.

  1. Accounting for California Water

    Escriva-Bou, Alvar; McCann, Henry; Hanak, Ellen; Lund, Jay; Gray, Brian


    Understanding California’s water balance sheet—how much there is, who has claims to it, and what is actually being “spent”—is key to effectively managing the state’s limited water supply in support of a healthy economy and environment. The latest drought has spotlighted serious gaps in California’s water accounting system. California is a large, geographically diverse state, and its water systems are physically interconnected and institutionally fragmented. Water infrastructure connects the s...

  2. Ball Bearing Analysis with the ORBIS Tool

    Halpin, Jacob D.


    Ball bearing design is critical to the success of aerospace mechanisms. Key bearing performance parameters, such as load capability, stiffness, torque, and life all depend on accurate determination of the internal load distribution. Hence, a good analytical bearing tool that provides both comprehensive capabilities and reliable results becomes a significant asset to the engineer. This paper introduces the ORBIS bearing tool. A discussion of key modeling assumptions and a technical overview is provided. Numerous validation studies and case studies using the ORBIS tool are presented. All results suggest the ORBIS code closely correlates to predictions on bearing internal load distributions, stiffness, deflection and stresses.

  3. Valve assembly having remotely replaceable bearings

    Johnson, Evan R.; Tanner, David E.


    A valve assembly having remotely replaceable bearings is disclosed wherein a valve disc is supported within a flow duct for rotation about a pair of axially aligned bearings, one of which is carried by a spindle received within a diametral bore in the valve disc, and the other of which is carried by a bearing support block releasably mounted on the duct circumferentially of an annular collar on the valve disc coaxial with its diametrical bore. The spindle and bearing support block are adapted for remote removal to facilitate servicing or replacement of the valve disc support bearings.

  4. Heuristic explanation of journal bearing instability

    Crandall, S. H.


    A fluid-filled journal bearing is viewed as a powerful pump circulating fluid around the annular space between the journal and the bearing. A small whirling motion of the journal generates a wave of thickness variation progressing around the channel. The hypothesis that the fluid flow drives the whirl whenever the mean of the pumped fluid velocity is greater than the peripheral speed of the thickness variation wave is discussed and compared with other simple explanations of journal bearing instability. It is shown that for non-cavitation long bearings the hypothesis predicts instability onset correctly for unloaded bearings but gradually overpredicts the onset speed as the load is increased.

  5. Simplifying Likelihood Ratios

    McGee, Steven


    Likelihood ratios are one of the best measures of diagnostic accuracy, although they are seldom used, because interpreting them requires a calculator to convert back and forth between “probability” and “odds” of disease. This article describes a simpler method of interpreting likelihood ratios, one that avoids calculators, nomograms, and conversions to “odds” of disease. Several examples illustrate how the clinician can use this method to refine diagnostic decisions at the bedside.

  6. Difference and ratio plots

    Svendsen, Anders Jørgen; Holmskov, U; Petersen, P H;


    hitherto unnoted differences between controls and patients with either rheumatoid arthritis or systemic lupus erythematosus. For this we use simple, but unconventional, graphic representations of the data, based on difference plots and ratio plots. Differences between patients with Burkitt's lymphoma...... and systemic lupus erythematosus from another previously published study (Macanovic, M. and Lachmann, P.J. (1979) Clin. Exp. Immunol. 38, 274) are also represented using ratio plots. Our observations indicate that analysis by regression analysis may often be misleading....

  7. Coupled Dynamics of a Rotor-Journal Bearing System Equipped with Thrust Bearings

    Yu Lie; R.B. Bhat


    The rotordynamic coefficients of fixed-pad thrust bearing are introduced and calculated by using the out-domain method, and a general analysis method is developed to investigate the coupled dynamics of a rotor equipped with journal and thrust bearings simultaneously. Considerations include the effects of static tilt parameters of the rotor on rotordynamic coefficients of thrust bearing and the action of thrust bearing on system dynamics. It is shown that thrust bearing changes the load distri...

  8. Components of bull and bear markets: bull corrections and bear rallies

    Maheu, John M; Thomas H. McCurdy; Yong Song


    Existing methods of partitioning the market index into bull and bear regimes do not identify market corrections or bear market rallies. In contrast, our probabilistic model of the return distribution allows for rich and heterogeneous intra-regime dynamics. We focus on the characteristics and dynamics of bear market rallies and bull market corrections, including, for example, the probability of transition from a bear market rally into a bull market versus back to the primary bear state. A Baye...

  9. Sperm counts and sperm sex ratio in male infertility patients

    Michael L Eisenberg; Lata Murthy; Kathleen Hwang; Dolores J Lamb; Larry I Lipshultz


    In recent years,investigators have noted a trend toward a declining proportion of male births in many industrialized nations.While men bear the sex-determining chromosome,the role of the female partner as it pertains to fertilization or miscarriage may also alter the gender ratio.We attempted to determine a man's secondary sex ratio (F1 generation) by directly examining the sex chromosomes of his sperm.We examined our male infertility clinic database for all men who had undergone a semen fluorescence in situ hybridization (FISH).Patient demographic and semen parameters were recorded.Chi-squared analysis was used to compare gender ratios (Ychromosomes/total chromosomes).Multivariable logistic regression was used to predict the odds of possessing a Y-bearing sperm after accounting for demographic and semen parameters.A total of 185 men underwent sperm FISH.For the entire cohort,the proportion of Y chromosome-bearing sperm was 51.5%.Men with less than five million motile sperm had a significantly lower proportion of Y chromosome-bearing sperm (50.8%) compared to men with higher sperm counts (51.6%; P=0.02).After multivariable adjustment,a higher sperm concentration,total motile sperm count and semen volume significantly increased the odds of having a Y chromosome-bearing sperm (P<0.01).As a man's sperm production declines,so does the proportion of Y chromosome-bearing sperm.Thus,a man's reproductive potential may predict his ability to sire male offspring.

  10. Chromatographic (TLC) differentiation of grizzly bear and black bear scats

    Picton, Harold D.; Kendall, Katherine C.


    While past work concluded that thin-layer chromatography (TLC) was inadequate for the separation of grizzly (Ursus arctos horribilis) and black bear (U. americanus) scats, our study found differences adequate for species separation. A key was constructed using 19 of 40 data points recorded on each(N)=356 profiles of 178) know-species scat. Accuracy was best for late summer scats (94%). Methods for specimen preparation, analysis, and reading the TLC profiles are discussed. Factors involved in scat variation were tested.

  11. A prototype construction of bearing heater system

    A bearing heater system has been successfully constructed using transformer-like method of 1000 VA power, 220 V primary voltage, and 50 Hz electrical frequency. The bearing heater consists of primary coil 230 turns, U type and bar-type iron core with 36 cm2, 9 cm2 ,and 3 cm2 cross-section, and electrical isolation. The bearing heater is used to enlarge the diameter of the bearing so that it can be easily fixed on an electric motor shaft during replacement because the heating is conducted by treated the bearing as a secondary coil of a transformer. This bearing heater can be used for bearing with 3 and 6 cm of inner diameter and 12 cm of maximum outside diameter. (author)

  12. Wave Journal Bearings Under Dynamic Loads

    Hendricks, Robert C.; Dimofte, Florin


    The dynamic behavior of the wave journal bearing was determined by running a three-wave bearing with an eccentrically mounted shaft. A transient analysis was developed and used to predict numerical data for the experimental cases. The three-wave journal bearing ran stably under dynamic loads with orbits well inside the bearing clearance. The orbits were almost circular and nearly free of the influence of, but dynamically dependent on, bearing wave shape. Experimental observations for both the absolute bearing-housing-center orbits and the relative bearing-housing-center-to-shaft-center orbits agreed well with the predictions. Moreover, the subsynchronous whirl motion generated by the fluid film was found experimentally and predicted theoretically for certain speeds.

  13. Genomic evidence of geographically widespread effect of gene flow from polar bears into brown bears.

    Cahill, James A; Stirling, Ian; Kistler, Logan; Salamzade, Rauf; Ersmark, Erik; Fulton, Tara L; Stiller, Mathias; Green, Richard E; Shapiro, Beth


    Polar bears are an arctic, marine adapted species that is closely related to brown bears. Genome analyses have shown that polar bears are distinct and genetically homogeneous in comparison to brown bears. However, these analyses have also revealed a remarkable episode of polar bear gene flow into the population of brown bears that colonized the Admiralty, Baranof and Chichagof islands (ABC islands) of Alaska. Here, we present an analysis of data from a large panel of polar bear and brown bear genomes that includes brown bears from the ABC islands, the Alaskan mainland and Europe. Our results provide clear evidence that gene flow between the two species had a geographically wide impact, with polar bear DNA found within the genomes of brown bears living both on the ABC islands and in the Alaskan mainland. Intriguingly, while brown bear genomes contain up to 8.8% polar bear ancestry, polar bear genomes appear to be devoid of brown bear ancestry, suggesting the presence of a barrier to gene flow in that direction. PMID:25490862

  14. Development and Evaluation of Titanium Spacesuit Bearings

    Rhodes, Richard; Battisti, Brian; Ytuarte, Raymond, Jr.; Schultz, Bradley


    The Z-2 Prototype Planetary Extravehicular Space Suit Assembly is a continuation of NASA's Z-series of spacesuits, designed with the intent of meeting a wide variety of exploration mission objectives, including human exploration of the Martian surface. Incorporating titanium bearings into the Z-series space suit architecture allows us to reduce mass by an estimated 23 lbs per suit system compared to the previously used stainless steel bearing race designs, without compromising suit functionality. There are two obstacles to overcome when using titanium for a bearing race- 1) titanium is flammable when exposed to the oxygen wetted environment inside the space suit and 2) titanium's poor wear properties are often challenging to overcome in tribology applications. In order to evaluate the ignitability of a titanium space suit bearing, a series of tests were conducted at White Sands Test Facility (WSTF) that introduced the bearings to an extreme test profile, with multiple failures imbedded into the test bearings. The testing showed no signs of ignition in the most extreme test cases; however, substantial wear of the bearing races was observed. In order to design a bearing that can last an entire exploration mission (approx. 3 years), design parameters for maximum contact stress need to be identified. To identify these design parameters, bearing test rigs were developed that allow for the quick evaluation of various bearing ball loads, ball diameters, lubricants, and surface treatments. This test data will allow designers to minimize the titanium bearing mass for a specific material and lubricant combination and design around a cycle life requirement for an exploration mission. This paper reviews the current research and testing that has been performed on titanium bearing races to evaluate the use of such materials in an enriched oxygen environment and to optimize the bearing assembly mass and tribological properties to accommodate for the high bearing cycle life for an

  15. Hydrostatic bearings for a turbine fluid flow metering device

    Fincke, J.R.


    A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion.

  16. Conditioning of alpha bearing wastes

    Alpha bearing wastes are generated during the reprocessing of spent fuel, mixed oxide fuel fabrication, decommissioning and other activities. The safe and effective management of these wastes is of particular importance owing to the radiotoxicity and long lived characteristics of certain transuranic (TRU) elements. The management of alpha bearing wastes involves a number of stages which include collection, characterization, segregation, treatment, conditioning, transport, storage and disposal. This report describes the currently available matrices and technologies for the conditioning of alpha wastes and relates them to their compatibility with the other stages of the waste management process. The selection of a specific immobilization process is dependent on the waste treatment state and the subsequent handling, transport, storage and disposal requirements. The overall objectives of immobilization are similar for all waste producers and processors, which are to produce: (a) Waste forms with sufficient mechanical, physical and chemical stability to satisfy all stages of handling, transport and storage (referred to as the short term requirements), and (b) Waste forms which will satisfy disposal requirements and inhibit the release of radionuclides to the biosphere (referred to as the long term requirements). Cement and bitumen processes have already been successfully applied to alpha waste conditioning on the industrial scale in many of the IAEA Member States. Cement systems based on BFS and pozzolanic cements have emerged as the principal encapsulation matrices for the full range of alpha bearing wastes. Alternative technologies, such as polymers and ceramics, are being developed for specific waste streams but are unlikely to meet widespread application owing to cost and process complexity. The merits of alpha waste conditioning are improved performance in transport, storage and disposal combined with enhanced public perception of waste management operations. These

  17. Obesity in California, 2012 and 2013

    U.S. Department of Health & Human Services — These data are from the 2013 California Dietary Practices Surveys (CDPS), 2012 California Teen Eating, Exercise and Nutrition Survey (CalTEENS), and 2013 California...

  18. California community water systems inventory dataset, 2010

    California Environmental Health Tracking Program — This data set contains information about all Community Water Systems in California. Data are derived from California Office of Drinking Water (ODW) Water Quality...

  19. Research on shielding neutron efficiency of some boron-bearing fabric and transparent resin materials

    The shielding neutron efficiency of boron-bearing materials developed recently is introduced. The thermal neutron shield ratios for two kinds of non-woven cloth with thickness of 58 mg/cm2 and 153 mg/cm2 are 51% and 79% respectively. Their mass attenuation coefficient for 0.186, 24.4 and 144 keV neutron are 1.56, 1.29 and 0.9 cm2/g respectively. The thermal neutron shield ratio is 85% for the natural boron-bearing transparent resin plate with the thickness of 0.59 g/cm2, and 97% for enriched boron or gadolinium bearing resin plate. The shield ratios of all three materials for 24.4 keV neutrons are 38%. The transparence of natural light for enriched boron-bearing resin plates shows no considerable change after they were exposed to thermal neutrons up to 6 Sv. After they were exposed up to 20 Sv, the transparence decreases to 50% but thermal neutron shield ratio does not change. The gadolinium-bearing plate has a very strong thermal neutron-capture gamma radiation and its dose-equivalent is greater than that of incident thermal neutrons

  20. Prepared to Learn: The Nature and Quality of Early Care and Education for Preschool-Age Children in California

    Karoly, Lynn A.; Ghosh-Dastidar, Bonnie; Zellman, Gail L.; Perlman, Michal; Fernyhough, Lynda


    To evaluate the adequacy and efficiency of preschool education, the RAND Corporation has undertaken the California Preschool Study to improve understanding of achievement gaps in the early elementary grades, the adequacy of preschool education currently given, and what efficiencies or additional resources might be brought to bear in early care and…

  1. Comparison of Alignment Correction Angles Between Fixed-Bearing and Mobile-Bearing UKA.

    Inoue, Atsuo; Arai, Yuji; Nakagawa, Shuji; Inoue, Hiroaki; Yamazoe, Shoichi; Kubo, Toshikazu


    Good outcomes have been reported with both fixed-bearing and mobile-bearing unicompartmental knee arthroplasty (UKA). However, overcorrected alignment could induce the progression of arthritis on the non-arthroplasty side. Changes of limb alignment after UKA with both types of bearings (fixed bearing: 24 knees, mobile bearing: 28 knees) were investigated. The mean difference between the preoperative standing femoral-tibial angle (FTA) and postoperative standing FTA was significantly larger in mobile bearing UKA group. In fixed-bearing UKA, there must be some laxity in MCL tension so that a 2-mm tension gauge can be inserted. In mobile-bearing UKA, appropriate MCL tension is needed to prevent bearing dislocation. This difference in MCL tension may have caused the difference in the correction angle between the groups. PMID:26264178

  2. Investigations of Slip Effect on the Performance of Micro Gas Bearings and Stability of Micro Rotor-Bearing Systems

    Jieyu Chen


    Full Text Available Incorporating the velocity slip effect of the gas flow at the solid boundary, theperformance and dynamic response of a micro gas-bearing-rotor system are investigated inthis paper. For the characteristic length scale of the micro gas bearing, the gas flow in thebearing resides in the slip regime rather than in the continuum regime. The modifiedReynolds equations of different slip models are presented. Gas pressure distribution and loadcarrying capacity are obtained by solving the Reynolds equations with finite differentmethod (FDM. Comparing results from different models, it is found that the second orderslip model agrees reasonably well with the benchmarked solutions obtained from thelinearized Boltzmann equation. Therefore, dynamic coefficients derived from the secondorder slip model are employed to evaluate the linear dynamic stability and vibrationcharacteristics of the system. Compared with the continuum flow model, the slip effectreduces dynamic coefficients of the micro gas bearing, and the threshold speed for stableoperation is consequently raised. Also, dynamic analysis shows that the system responseschange with variation of the operating parameters including the eccentricity ratio, therotational speed, and the unbalance ratio.

  3. Seismic isolation rubber bearings for nuclear facilities

    This paper describes results of biaxial breaking tests by compression and shear and by tension and shear for seismic isolation rubber bearings with bolted-type connections. The bearings used in the tests were low-damping rubber bearings, high-damping rubber bearings, and lead-rubber bearings. Three modes of failure of the bolted-type bearings were observed in the tests. They are the breaking failure by tension and shear; the breaking failure by compression and shear; and the buckling failure by compression and shear. The first and the second modes of failures are almost independent of the types and the sizes of the bearings. The breaking conditions of those failure modes are described in the axial stress-shear strain plane. This expression is useful for the evaluation of safety margins of the bearings. The paper outlines the basic design of the nuclear-grade bearings which were used for large-scale rubber bearing tests in a research project for seismic isolation of fast breeder reactor (FBR) plants. The paper also discusses the protection method against aging and the quality control which are important for implementation

  4. The Effect of California's Budget Cuts on Lesbian, Gay, Bisexual, and Transgender People and Their Children


    California faces a $26.3 million budget shortfall for the approaching fiscal year. In an effort to balance the budget, cuts are likely to some of California’s most vital services and programs including Medi-Cal, the State’s healthcare option for low-income children, families, elderly, and disabled. The poor, elderly, and disabled will undoubtedly bear a significant share of these cuts. This research note uses the 2007 California Health Interview Survey (CHIS) to explore the potential conseque...

  5. Interference Fit Life Factors for Roller Bearings

    Oswald, Fred B.; Zaretsky, Erwin V.; Poplawski, Joseph V.


    The effect of hoop stresses in reducing cylindrical roller bearing fatigue life was determined for various classes of inner ring interference fit. Calculations were performed for up to seven interference fit classes for each of ten bearing sizes. Each fit was taken at tightest, average and loosest values within the fit class for RBEC-5 tolerance, thus requiring 486 separate analyses. The hoop stresses were superimposed on the Hertzian principal stresses created by the applied radial load to calculate roller bearing fatigue life. The method was developed through a series of equations to calculate the life reduction for cylindrical roller bearings based on interference fit. All calculated lives are for zero initial bearing internal clearance. Any reduction in bearing clearance due to interference fit was compensated by increasing the initial (unmounted) clearance. Results are presented as tables and charts of life factors for bearings with light, moderate and heavy loads and interference fits ranging from extremely light to extremely heavy and for bearing accuracy class RBEC 5 (ISO class 5). Interference fits on the inner bearing ring of a cylindrical roller bearing can significantly reduce bearing fatigue life. In general, life factors are smaller (lower life) for bearings running under light load where the unfactored life is highest. The various bearing series within a particular bore size had almost identical interference fit life factors for a particular fit. The tightest fit at the high end of the RBEC-5 tolerance band defined in ANSI/ABMA shaft fit tables produces a life factor of approximately 0.40 for an inner-race maximum Hertz stress of 1200 MPa (175 ksi) and a life factor of 0.60 for an inner-race maximum Hertz stress of 2200 MPa (320 ksi). Interference fits also impact the maximum Hertz stress-life relation.

  6. Zinc, cadmium, mercury and selenium in polar bears (Ursus maritimus) from Central East Greenland

    Dietz, R. [Greenland Environmental Research Institute, Copenhagen (Denmark); Born, E.W. [Greenland Fisheries Research Institute, Copenhagen (Denmark); Agger, C.T. [National Environmental Research Institute, Roskilde (Denmark); Nielsen, C.O. [Ravnsnaesvej, Birkerod (Denmark)


    Muscle, liver, and kidney tissues from 38 polar bears (Ursus maritimus) caught in the Scoresby Sound area, Central East Greenland, were analysed for zinc, cadmium, mercury and selenium. In general, cadmium concentrations were low in muscle, liver and kidney tissue. This finding can be explained by low cadmium levels in the blubber of ringed seals. The concentration of mercury in muscle tissue was low, whereas concentrations in liver and kidney tissue were relatively high. Mercury and cadmium were positively correlated with age in liver and kidney. Zinc was positively correlated with in kidney, and selenium was correlated with age in liver. Contrary to other marine mammals, polar bears had higher mercury levels in the kidneys than in the liver. In all three tissues polar bears had significantly lower cadmium levels than ringed seals from the same area. Mercury levels were significantly lower in the muscle tissue of polar bears than in ringed seals, where-as levels in the liver and kidney were significantly higher. The previous geographic trend for cadmium and mercury found in Canadian polar bears could be extended to cover East Greenland as well. Hence cadmium levels were higher in Greenland than in Canada, while the opposite was the case for mercury. Greenland polar bears had higher mercury and cadmium contents in livers and kidneys than polar bears from Svalbard. The mercury levels in muscle and liver tissue from polar bears from East Greenland were twice as high as found in bears from western Alaska, but half the levels found in northern Alaska. Cadmium and zinc were partially correlated in kidney tissue, and this was found for mercury and selenium as well. Cadmium and zinc showed molar ratios close to unity with the highest concentrations occurring in kidney tissue, while the levels of zinc exceeded cadmium in muscle and liver tissue by up to several decades. Mercury and selenium showed molar ratios close to unity in liver and kidneys. 56 refs., 5 figs., 6 tabs.

  7. California's geothermal resource potential

    Leibowitz, L. P.


    According to a U.S. Geological Survey estimate, recoverable hydrothermal energy in California may amount to 19,000 MW of electric power for a 30-year period. At present, a geothermal installation in the Geysers region of the state provides 502 MWe of capacity; an additional 1500 MWe of electric generating capacity is scheduled to be in operation in geothermal fields by 1985. In addition to hydrothermal energy sources, hot-igneous and conduction-dominated resources are under investigation for possible development. Land-use conflicts, environmental concerns and lack of risk capital may limit this development.

  8. Coupled Dynamics of a Rotor-Journal Bearing System Equipped with Thrust Bearings

    Yu Lie


    Full Text Available The rotordynamic coefficients of fixed-pad thrust bearing are introduced and calculated by using the out-domain method, and a general analysis method is developed to investigate the coupled dynamics of a rotor equipped with journal and thrust bearings simultaneously. Considerations include the effects of static tilt parameters of the rotor on rotordynamic coefficients of thrust bearing and the action of thrust bearing on system dynamics. It is shown that thrust bearing changes the load distribution of journal bearings and the static deflection of the rotor and delays the instability of the system considerably in lateral shaft vibration.

  9. The rectilinear Steiner ratio

    PO de Wet


    Full Text Available The rectilinear Steiner ratio was shown to be 3/2 by Hwang [Hwang FK, 1976, On Steiner minimal trees with rectilinear distance, SIAM Journal on Applied Mathematics, 30, pp. 104– 114.]. We use continuity and introduce restricted point sets to obtain an alternative, short and self-contained proof of this result.

  10. The Reference Return Ratio

    Nicolaisen, Jeppe; Faber Frandsen, Tove


    The paper introduces a new journal impact measure called The Reference Return Ratio (3R). Unlike the traditional Journal Impact Factor (JIF), which is based on calculations of publications and citations, the new measure is based on calculations of bibliographic investments (references) and returns...

  11. California Tiger Salamander Range - CWHR [ds588

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model...

  12. California Fish Passage Assessment Database [ds69

    California Department of Resources — The Passage Assessment Database shapefile contains locations of known and potential barriers to salmonid migration in California streams with additional information...

  13. Giant Reed Distribution - Northern California [ds333

    California Department of Resources — The Arundo Distribution layer is a compilation of Arundo donax observations in northern and central California, obtained from several sources, including Arundo...

  14. Bearing Health Assessment Based on Chaotic Characteristics

    Chen Lu


    Full Text Available Vibration signals extracted from rotating parts of machinery carry a lot of useful information about the condition of operating machine. Due to the strong non-linear, complex and non-stationary characteristics of vibration signals from working bearings, an accurate and reliable health assessment method for bearing is necessary. This paper proposes to utilize the selected chaotic characteristics of vibration signal for health assessment of a bearing by using self-organizing map (SOM. Both Grassberger-Procaccia algorithm and Takens' theory are employed to calculate the characteristic vector which includes three chaotic characteristics, such as correlation dimension, largest Lyapunov exponent and Kolmogorov entropy. After that, SOM is used to map the three corresponding characteristics into a confidence value (CV which represents the health state of the bearing. Finally, a case study based on vibration datasets of a group of testing bearings was conducted to demonstrate that the proposed method can reliably assess the health state of bearing.

  15. Experts Question California's Algebra Edict

    Cavanagh, Sean


    Business leaders from important sectors of the American economy have been urging schools to set higher standards in math and science--and California officials, in mandating that 8th graders be tested in introductory algebra, have responded with one of the highest such standards in the land. Still, many California educators and school…

  16. Resource Cards on California Schools

    EdSource, 2007


    This convenient spiral-bound volume contains the latest data on school finance as well as information on students, teachers, and California's accountability system. The 37-card 2007 edition provides fingertip access to the latest information about California's education system. They are separated into sections that cover related topics. Each…

  17. Female Superintendent Longevity in California

    Rohlfing, Tracy


    The purpose of this study was to investigate, through narrative inquiry (Clandinin & Connelly, 2000), the leadership evolution of five female superintendents in California with longevity of 5 or more years in their current school district positions. The research question addressed was, "How do California female superintendents evolve to…

  18. Hydrogen energy system in California

    Results of experiences on the use of hydrogen as a clean burning fuel in California and results of the South Coast Air Quality Management district tests using hydrogen as a clean burning environmentally safe fuel are given. The results of Solar Hydrogen Projects in California and recent medical data documentation of human lung damage of patients living in air polluted urban areas are summarized

  19. Hydrodynamic bearing for light loaded turbo machinery

    The rotor of any turbo-machinery running in journal bearings is prone to two types of well-known vibrations. Synchronous Vibrations occur due to run out or forces resulting from unbalancing of the shaft. Sub synchronous vibrations are more serious, this phenomenon is commonly associated with oil film forces of the journal bearing. In order to avoid sub synchronous vibrations, different types of journal bearings having helical grooves were investigated both theoretically and experimentally. (author)

  20. Probabilistic Aspect of Rolling Bearings Durability

    Styp-Rekowski, Michał


    Many factors generate situations that real dimensions of each machine elements are different from nominal ones. In the case of rolling bearings elements mentioned disagreements are small - their values are rank of micrometers. However, such small differences can generate significant changes of operational features of bearings. The analysis of influence of ball dimensional deviation on load distribution in ball bearings is presented in this paper. The probability of occurrence of ball diameter...

  1. A miniature tilting pad gas lubricated bearing

    Sixsmith, H.; Swift, W. L.


    This paper describes the design and development of a miniature tilting pad gas bearing developed for use in very small turbomachines. The bearings have been developed for cryogenic turboexpanders with shaft diameters down to about 0.3 cm and rotational speeds up to one million rpm. Cryogenic expansion turbines incorporating this type of bearing should be suitable for refrigeration rates down to about 10 w.

  2. Bearing fault diagnosis based on vibration signals.

    Abdusslam, S.A.; Gu, Fengshou; Ball, Andrew


    The vibration signal obtained from operating machines contains information relating to machine condition as well as noise. Further processing of the signal is necessary to elicit information particularly relevant to bearing faults. Many techniques have been employed to process the vibration signals in bearing faults detection and diagnosis. Two common techniques, time domain techniques and frequency domain techniques are used in this paper to investigate bearings condition.

  3. 1991 : California gas wars explode



    In 1991, the California Public Utilities Commission (CPUC) made an attempt to make the California energy market more competitive and targeted the long-standing relationship between gas producers in Alberta and California's gas distributor Pacific Gas and Electric (PG and E). The utility's buying division, Alberta and Southern Gas, had offered a new contract to Alberta producers that would have resulted in a 25 per cent price reduction. The market represented $1 billion annual revenue for Alberta producers, with 40 per cent of Canadian gas exports going to California. The former chief economist with the United States Senate Energy Committee estimated that Alberta producers were overcharging California ratepayers by $250 million per year. Other key events in 1991 included the National Energy Board's announcement that it would move its headquarters to Calgary, and Nova Corporation sold its 43 per cent stake in Husky Oil. 1 tab., 1 fig.

  4. Progress in California

    Gipe, P.


    Though the wind energy continues to take it on the chin in the rough and tumble of California's celebrity politics, several indicators are pointing toward a modest revival. First several new reports laud wind energy at good sites as now competitive with conventional sources. Second, utility subsidiaries are signaling their approval by cautiously venturing into the technology. Also, technological refinements and reorganizations continue while a demand for new generating capacity may be developing in the state. Three new reports all paint a picture of wind energy finally coming of age. The California Energy Commission's most recent Energy Technology Status report says that wind-generated electricity is competitive with coal, oil, gas, and most other technologies. Similarly, a staff report found that after tallying the economic, social, and environmental costs, wind was one of the least cost sources of new generation. Most recently the Electric Power Research Institute's Journal reported the wind energy, at about 8 cents/k Wh, is equivalent to generation from conventional sources.

  5. Intake to Production Ratio

    Nazaroff, William; Weschler, Charles J.; Little, John C.;


    BACKGROUND: Limited data are available to assess human exposure to thousands of chemicals currently in commerce. Information that relates human intake of a chemical to its production and use can help inform understanding of mechanisms and pathways that control exposure and support efforts...... to protect public health.OBJECTIVES: We introduce the intake-to-production ratio (IPR) as an economy-wide quantitative indicator of the extent to which chemical production results in human exposure.METHODS: The IPR was evaluated as the ratio of two terms: aggregate rate of chemical uptake in a human...... span many orders of magnitude from a low of 0.6 ppm for bisphenol A to a high of > 180,000 ppm for methyl paraben. Intermediate results were obtained for five phthalates and two chlorinated aromatic compounds: 120 ppm for butyl benzyl phthalate, 670 ppm for di(2-ethylhexyl) phthalate, 760 ppm for di...

  6. R+D works for the further development of high temperature reactors. (1) Captive bearing experiments for active magnetic bearings. (2) Captive bearing test for HTR blowers

    When using active magnetic bearings as blower shaft bearings, blower motors and bearings must be protected against mechanical damage in case of faults (example: total electrical supply failure due to the supply cables breaking). So-called captive bearings are provided, in order to be able to shut the blowers down safely in such faults. These captive bearings are roller bearings which are additionally fitted in the area of the blower shaft bearings, to prevent mechanical contact between the blower rotor and stator. As there was little experience available for the given boundary conditions, such as - speed, - acceleration, - bearing load, - bearing dimensions, - ambient conditions, appropriate development and tests had to be carried out. It was important to determine suitable captive bearings and the necessary ambient conditions, which will make it possible to support the failures of the magnetic bearings to be expected in 40 years' operation of the reactor without damage and to meet the requirements of the captive bearings. (orig./GL)

  7. Multivariate variance ratio statistics

    Hong, Seok Young; Linton, Oliver; Zhang, Hui Jun


    We propose several multivariate variance ratio statistics. We derive the asymptotic distribution of the statistics and scalar functions thereof under the null hypothesis that returns are unpredictable after a constant mean adjustment (i.e., under the Efficient Market Hypothesis). We do not impose the no leverage assumption of Lo and MacKinlay (1988) but our asymptotic standard errors are relatively simple and in particular do not require the selection of a band- width parameter. We extend the...

  8. Bear Capture. Research, and Request for Consideraton of Releases of Bears at Dahomey NWR in 1996

    US Fish and Wildlife Service, Department of the Interior — A series of memos and correspondences concerning the capture of a bear in Cleveland, MS and release on Dahomey NWR along with graduate research on bears from...

  9. Dynamic modelling and response characteristics of a magnetic bearing rotor system with auxiliary bearings

    Free, April M.; Flowers, George T.; Trent, Victor S.


    Auxiliary bearings are a critical feature of any magnetic bearing system. They protect the soft iron core of the magnetic bearing during an overload or failure. An auxiliary bearing typically consists of a rolling element bearing or bushing with a clearance gap between the rotor and the inner race of the support. The dynamics of such systems can be quite complex. It is desired to develop a rotordynamic model which describes the dynamic behavior of a flexible rotor system with magnetic bearings including auxiliary bearings. The model is based upon an experimental test facility. Some simulation studies are presented to illustrate the behavior of the model. In particular, the effects of introducing sideloading from the magnetic bearing when one coil fails is studied.

  10. Dynamic modelling and response characteristics of a magnetic bearing rotor system including auxiliary bearings

    Free, April M.; Flowers, George T.; Trent, Victor S.


    Auxiliary bearings are a critical feature of any magnetic bearing system. They protect the soft iron core of the magnetic bearing during an overload or failure. An auxiliary bearing typically consists of a rolling element bearing or bushing with a clearance gap between the rotor and the inner race of the support. The dynamics of such systems can be quite complex. It is desired to develop a rotor-dynamic model and assess the dynamic behavior of a magnetic bearing rotor system which includes the effects of auxiliary bearings. Of particular interest is the effects of introducing sideloading into such a system during failure of the magnetic bearing. A model is developed from an experimental test facility and a number of simulation studies are performed. These results are presented and discussed.