Sample records for minimum sticking efficiency

  1. Transport of Escherichia coli in 25 m quartz sand columns

    NASA Astrophysics Data System (ADS)

    Lutterodt, G.; Foppen, J. W. A.; Maksoud, A.; Uhlenbrook, S.

    2011-01-01

    To help improve the prediction of bacteria travel distances in aquifers laboratory experiments were conducted to measure the distant dependent sticking efficiencies of two low attaching Escherichia coli strains (UCFL-94 and UCFL-131). The experimental set up consisted of a 25 m long helical column with a diameter of 3.2 cm packed with 99.1% pure-quartz sand saturated with a solution of magnesium sulfate and calcium chloride. Bacteria mass breakthrough at sampling distances ranging from 6 to 25.65 m were observed to quantify bacteria attachment over total transport distances ( αL) and sticking efficiencies at large intra-column segments ( αi) (> 5 m). Fractions of cells retained ( Fi) in a column segment as a function of αi were fitted with a power-law distribution from which the minimum sticking efficiency defined as the sticking efficiency of 0.001% bacteria fraction of the total input mass retained that results in a 5 log removal were extrapolated. Low values of αL in the order 10 - 4 and 10 - 3 were obtained for UCFL-94 and UCFL-131 respectively, while αi-values ranged between 10 - 6 to 10 - 3 for UCFL-94 and 10 - 5 to 10 - 4 for UCFL-131. In addition, both αL and αi reduced with increasing transport distance, and high coefficients of determination (0.99) were obtained for power-law distributions of αi for the two strains. Minimum sticking efficiencies extrapolated were 10 - 7 and 10 - 8 for UCFL-94 and UCFL-131, respectively. Fractions of cells exiting the column were 0.19 and 0.87 for UCFL-94 and UCL-131, respectively. We concluded that environmentally realistic sticking efficiency values in the order of 10 - 4 and 10 - 3 and much lower sticking efficiencies in the order 10 - 5 are measurable in the laboratory, Also power-law distributions in sticking efficiencies commonly observed for limited intra-column distances (< 2 m) are applicable at large transport distances(> 6 m) in columns packed with quartz grains. High fractions of bacteria populations may possess the so-called minimum sticking efficiency, thus expressing their ability to be transported over distances longer than what might be predicted using measured sticking efficiencies from experiments with both short (< 1 m) and long columns (> 25 m). Also variable values of sticking efficiencies within and among the strains show heterogeneities possibly due to variations in cell surface characteristics of the strains. The low sticking efficiency values measured express the importance of the long columns used in the experiments and the lower values of extrapolated minimum sticking efficiencies makes the method a valuable tool in delineating protection areas in real-world scenarios.

  2. 7 CFR 3201.88 - Agricultural spray adjuvants.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... with the herbicide, pesticide, or fertilizer formulas that will improve the efficiency and the effectiveness of the chemicals, including sticking agents, wetting agents, etc. (b) Minimum biobased content...

  3. 7 CFR 3201.88 - Agricultural spray adjuvants.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... with the herbicide, pesticide, or fertilizer formulas that will improve the efficiency and the effectiveness of the chemicals, including sticking agents, wetting agents, etc. (b) Minimum biobased content...

  4. fM to aM nucleic acid amplification for molecular diagnostics in a non-stick-coated metal microfluidic bioreactor

    PubMed Central

    Huang, Guoliang; Huang, Qin; Ma, Li; Luo, Xianbo; Pang, Biao; Zhang, Zhixin; Wang, Ruliang; Zhang, Junqi; Li, Qi; Fu, Rongxin; Ye, Jiancheng

    2014-01-01

    A sensitive DNA isothermal amplification method for the detection of DNA at fM to aM concentrations for pathogen identification was developed using a non-stick-coated metal microfluidic bioreactor. A portable confocal optical detector was utilized to monitor the DNA amplification in micro- to nanoliter reaction assays in real-time, with fluorescence collection near the optical diffraction limit. The non-stick-coated metal microfluidic bioreactor, with a surface contact angle of 103°, was largely inert to bio-molecules, and DNA amplification could be performed in a minimum reaction volume of 40 nL. The isothermal nucleic acid amplification for Mycoplasma pneumoniae identification in the non-stick-coated microfluidic bioreactor could be performed at a minimum DNA template concentration of 1.3 aM, and a detection limit of three copies of genomic DNA was obtained. This microfluidic bioreactor offers a promising clinically relevant pathogen molecular diagnostic method via the amplification of targets from only a few copies of genomic DNA from a single bacterium. PMID:25475544

  5. Control at stability's edge minimizes energetic costs: expert stick balancing

    PubMed Central

    Meyer, Ryan; Zhvanetsky, Max; Ridge, Sarah; Insperger, Tamás

    2016-01-01

    Stick balancing on the fingertip is a complex voluntary motor task that requires the stabilization of an unstable system. For seated expert stick balancers, the time delay is 0.23 s, the shortest stick that can be balanced for 240 s is 0.32 m and there is a ° dead zone for the estimation of the vertical displacement angle in the saggital plane. These observations motivate a switching-type, pendulum–cart model for balance control which uses an internal model to compensate for the time delay by predicting the sensory consequences of the stick's movements. Numerical simulations using the semi-discretization method suggest that the feedback gains are tuned near the edge of stability. For these choices of the feedback gains, the cost function which takes into account the position of the fingertip and the corrective forces is minimized. Thus, expert stick balancers optimize control with a combination of quick manoeuvrability and minimum energy expenditures. PMID:27278361

  6. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Menikoff, Ralph

    Previously the SURFplus reactive burn model was calibrated for the TATB based explosive PBX 9502. The calibration was based on fitting Pop plot data, the failure diameter and the limiting detonation speed, and curvature effect data for small curvature. The model failure diameter is determined utilizing 2-D simulations of an unconfined rate stick to find the minimum diameter for which a detonation wave propagates. Here we examine the effect of mesh resolution on an unconfined rate stick with a diameter (10mm) slightly greater than the measured failure diameter (8 to 9 mm).

  7. New Surface-Treatment Technique of Concrete Structures Using Crack Repair Stick with Healing Ingredients

    PubMed Central

    Ahn, Tae-Ho; Kim, Hong-gi; Ryou, Jae-Suk

    2016-01-01

    This study focused on the development of a crack repair stick as a new repair method along with self-healing materials that can be used to easily repair the cracks in a concrete structure at the construction site. In developing this new repair technique, the self-healing efficiency of various cementitious materials was considered. Likewise, a crack repair stick was developed to apply to concrete structures with 0.3 mm or lower crack widths. The crack repair stick was made with different materials, such as cement, an expansive material (C12A7), a swelling material, and calcium carbonate, to endow it with a self-healing property. To verify the performance of the crack repair stick for concrete structures, two types of procedures (field experiment and field absorption test) were carried out. As a result of such procedures, it was concluded that the developed crack repair stick could be used on concrete structures to reduce repair expenses and for the improved workability, usability, and serviceability of such structures. On the other hand, to evaluate the self-healing performance of the crack repair stick, various tests were conducted, such as the relative dynamic modulus of elasticity test, the water tightness test, the water permeability test, observation via a microscope, and scanning electron microscope (SEM) analysis. From the results, it is found that water leakage can be prevented and that the durability of a concrete structure can be improved through self-healing. Also, it was verified that the cracks were perfectly closed after 28 days due to application of the crack repair stick. These results indicate the usability of the crack repair stick for concrete structures, and its self-healing efficiency. PMID:28773776

  8. The effect of surface characteristics on the transport of multiple Escherichia coli isolates in large scale columns of quartz sand.

    PubMed

    Lutterodt, G; Basnet, M; Foppen, J W A; Uhlenbrook, S

    2009-02-01

    Bacteria properties play an important role in the transport of bacteria in groundwater, but their role, especially for longer transport distances (>0.5 m) has not been studied. Thereto, we studied the effects of cell surface hydrophobicity, outer surface potential (OSP), cell sphericity, motility, and Ag43 protein expression on the outer cell surface for a number of E. coli strains, obtained from the environment on their transport behavior in columns of saturated quartz sand of 5 m height in two solutions: demineralized (DI) water and artificial groundwater (AGW). In DI water, sticking efficiencies ranged between 0.1 and 0.4 at the column inlet, and then decreased with transport distance to 0.02-0.2. In AGW, sticking efficiencies were on average 1log-unit higher than those in DI (water). Bacteria motility and Ag43 expression affected attachment with a (high) statistical significance. In contrast, hydrophobicity, OSP and cell sphericity did not significantly correlate with sticking efficiency. However, for transport distances more than 0.33 m, the correlation between sticking efficiency, Ag43 expression, and motility became insignificant. We concluded that Ag43 and motility played an important role in E. coli attachment to quartz grain surfaces, and that the transport distance dependent sticking efficiency reductions were caused by motility and Ag43 expression variations within a population. The implication of our findings is that less motile bacteria with little or no Ag43 expression may travel longer distances once they enter groundwater environments. In future studies, the possible effect of bacteria surface structures, like fimbriae, pili and surface proteins on bacteria attachment need to be considered more systematically in order to arrive at more meaningful inter-population comparisons of the transport behavior of E. coli strains in aquifers.

  9. Design of a Minimum Surface-Effect Three Degree-of-Freedom Micromanipulator

    NASA Technical Reports Server (NTRS)

    Goldfarb, Michael; Speich, John E.

    1997-01-01

    This paper describes the fundamental physical motivations for small-scale minimum surface-effect design, and presents a three degree-of-freedom micromanipulator design that incorporates a minimum surface-effect approach. The primary focus of the design is the split-tube flexure, a unique small-scale revolute joint that exhibits a considerably larger range of motion and significantly better multi-axis revolute joint characteristics than a conventional flexure. The development of this joint enables the implementation of a small-scale spatially-loaded revolute joint-based manipulator with well-behaved kinematic characteristics and without the backlash and stick-slip behavior that would otherwise prevent precision control

  10. Low-Profile, Dual-Wavelength, Dual-Polarized Antenna

    NASA Technical Reports Server (NTRS)

    Carswell, James R.

    2010-01-01

    A single-aperture, low-profile antenna design has been developed that supports dual-polarization and simultaneous operation at two wavelengths. It realizes multiple beams in the elevation plane, and supports radiometric, radar, and conical scanning applications. This antenna consists of multiple azimuth sticks, with each stick being a multilayer, hybrid design. Each stick forms the h-plane pattern of the C and Ku-band vertically and horizontally polarized antenna beams. By combining several azimuth sticks together, the elevation beam is formed. With a separate transceiver for each stick, the transmit phase and amplitude of each stick can be controlled to synthesize a beam at a specific incidence angle and to realize a particular side-lobe pattern. By changing the transmit phase distribution through the transceivers, the transmit antenna beam can be steered to different incidence angles. By controlling the amplitude distribution, different side lobe patterns and efficiencies can be realized. The receive beams are formed using digital beam synthesis techniques, resulting in very little loss in the receive path, thus enabling a very-low loss receive antenna to support passive measurements.

  11. Logistic Stick-Breaking Process

    PubMed Central

    Ren, Lu; Du, Lan; Carin, Lawrence; Dunson, David B.

    2013-01-01

    A logistic stick-breaking process (LSBP) is proposed for non-parametric clustering of general spatially- or temporally-dependent data, imposing the belief that proximate data are more likely to be clustered together. The sticks in the LSBP are realized via multiple logistic regression functions, with shrinkage priors employed to favor contiguous and spatially localized segments. The LSBP is also extended for the simultaneous processing of multiple data sets, yielding a hierarchical logistic stick-breaking process (H-LSBP). The model parameters (atoms) within the H-LSBP are shared across the multiple learning tasks. Efficient variational Bayesian inference is derived, and comparisons are made to related techniques in the literature. Experimental analysis is performed for audio waveforms and images, and it is demonstrated that for segmentation applications the LSBP yields generally homogeneous segments with sharp boundaries. PMID:25258593

  12. Investigation of PDC bit failure base on stick-slip vibration analysis of drilling string system plus drill bit

    NASA Astrophysics Data System (ADS)

    Huang, Zhiqiang; Xie, Dou; Xie, Bing; Zhang, Wenlin; Zhang, Fuxiao; He, Lei

    2018-03-01

    The undesired stick-slip vibration is the main source of PDC bit failure, such as tooth fracture and tooth loss. So, the study of PDC bit failure base on stick-slip vibration analysis is crucial to prolonging the service life of PDC bit and improving ROP (rate of penetration). For this purpose, a piecewise-smooth torsional model with 4-DOF (degree of freedom) of drilling string system plus PDC bit is proposed to simulate non-impact drilling. In this model, both the friction and cutting behaviors of PDC bit are innovatively introduced. The results reveal that PDC bit is easier to fail than other drilling tools due to the severer stick-slip vibration. Moreover, reducing WOB (weight on bit) and improving driving torque can effectively mitigate the stick-slip vibration of PDC bit. Therefore, PDC bit failure can be alleviated by optimizing drilling parameters. In addition, a new 4-DOF torsional model is established to simulate torsional impact drilling and the effect of torsional impact on PDC bit's stick-slip vibration is analyzed by use of an engineering example. It can be concluded that torsional impact can mitigate stick-slip vibration, prolonging the service life of PDC bit and improving drilling efficiency, which is consistent with the field experiment results.

  13. Exploring load, velocity, and surface disorder dependence of friction with one-dimensional and two-dimensional models.

    PubMed

    Dagdeviren, Omur E

    2018-08-03

    The effect of surface disorder, load, and velocity on friction between a single asperity contact and a model surface is explored with one-dimensional and two-dimensional Prandtl-Tomlinson (PT) models. We show that there are fundamental physical differences between the predictions of one-dimensional and two-dimensional models. The one-dimensional model estimates a monotonic increase in friction and energy dissipation with load, velocity, and surface disorder. However, a two-dimensional PT model, which is expected to approximate a tip-sample system more realistically, reveals a non-monotonic trend, i.e. friction is inert to surface disorder and roughness in wearless friction regime. The two-dimensional model discloses that the surface disorder starts to dominate the friction and energy dissipation when the tip and the sample interact predominantly deep into the repulsive regime. Our numerical calculations address that tracking the minimum energy path and the slip-stick motion are two competing effects that determine the load, velocity, and surface disorder dependence of friction. In the two-dimensional model, the single asperity can follow the minimum energy path in wearless regime; however, with increasing load and sliding velocity, the slip-stick movement dominates the dynamic motion and results in an increase in friction by impeding tracing the minimum energy path. Contrary to the two-dimensional model, when the one-dimensional PT model is employed, the single asperity cannot escape to the minimum energy minimum due to constraint motion and reveals only a trivial dependence of friction on load, velocity, and surface disorder. Our computational analyses clarify the physical differences between the predictions of the one-dimensional and two-dimensional models and open new avenues for disordered surfaces for low energy dissipation applications in wearless friction regime.

  14. Peel-and-Stick: Fabricating Thin Film Solar Cell on Universal Substrates

    PubMed Central

    Lee, Chi Hwan; Kim, Dong Rip; Cho, In Sun; William, Nemeth; Wang, Qi; Zheng, Xiaolin

    2012-01-01

    Fabrication of thin-film solar cells (TFSCs) on substrates other than Si and glass has been challenging because these nonconventional substrates are not suitable for the current TFSC fabrication processes due to poor surface flatness and low tolerance to high temperature and chemical processing. Here, we report a new peel-and-stick process that circumvents these fabrication challenges by peeling off the fully fabricated TFSCs from the original Si wafer and attaching TFSCs to virtually any substrates regardless of materials, flatness and rigidness. With the peel-and-stick process, we integrated hydrogenated amorphous silicon (a-Si:H) TFSCs on paper, plastics, cell phone and building windows while maintaining the original 7.5% efficiency. The new peel-and-stick process enables further reduction of the cost and weight for TFSCs and endows TFSCs with flexibility and attachability for broader application areas. We believe that the peel-and-stick process can be applied to thin film electronics as well. PMID:23277871

  15. Peel-and-Stick: Fabricating Thin Film Solar Cell on Universal Substrates

    NASA Astrophysics Data System (ADS)

    Lee, Chi Hwan; Kim, Dong Rip; Cho, In Sun; William, Nemeth; Wang, Qi; Zheng, Xiaolin

    2012-12-01

    Fabrication of thin-film solar cells (TFSCs) on substrates other than Si and glass has been challenging because these nonconventional substrates are not suitable for the current TFSC fabrication processes due to poor surface flatness and low tolerance to high temperature and chemical processing. Here, we report a new peel-and-stick process that circumvents these fabrication challenges by peeling off the fully fabricated TFSCs from the original Si wafer and attaching TFSCs to virtually any substrates regardless of materials, flatness and rigidness. With the peel-and-stick process, we integrated hydrogenated amorphous silicon (a-Si:H) TFSCs on paper, plastics, cell phone and building windows while maintaining the original 7.5% efficiency. The new peel-and-stick process enables further reduction of the cost and weight for TFSCs and endows TFSCs with flexibility and attachability for broader application areas. We believe that the peel-and-stick process can be applied to thin film electronics as well.

  16. PIGE-PIXE analysis of chewing sticks of pharmacological importance

    NASA Astrophysics Data System (ADS)

    Olabanji, S. O.; Makanju, O. V.; Haque, A. M. I.; Buoso, M. C.; Ceccato, D.; Cherubini, R.; Moschini, G.

    1996-06-01

    PIGE and PIXE techniques were employed for the determination of the major, minor and trace elemental concentrations in chewing sticks of pharmacological importance namely: Butyrospermum paradoxum, Garcinia kola, Distemonanthus benthamianus, Bridelia ferruginea, Anogeissus leiocarpus, Terminalia glaucescens and Fagara rubescens, respectively. The concentration of fluorine which is very important for human dental enamel was specially determined using the 19F(p, p'γ) 19F reaction. For decades these chewing sticks when used alone without toothpastes have proven to be very efficient, effective and reliable in cleaning the teeth of many people particularly in Nigeria and some other countries in Africa. The teeth of users are usually very strong, clean, fresh and devoid of germs and caries. Even with the advent of modern toothpastes with special additions of fluorine, the use of these popular and efficient chewing sticks is still unabated. Many people including the elite use them solely, a few others combine their use with modern toothpastes and brush. Proton beams produced by the 7 MV CN and 2.5 MV AN 2000 Van de Graaff accelerators at INFN, Laboratori Nazionali di Legnaro (LNL), Padova, Italy were used for the PIGE and PIXE analysis, respectively. Results of this novel study are presented and discussed.

  17. Peel-and-Stick: Mechanism Study for Efficient Fabrication of Flexible/Transparent Thin-film Electronics

    NASA Astrophysics Data System (ADS)

    Lee, Chi Hwan; Kim, Jae-Han; Zou, Chenyu; Cho, In Sun; Weisse, Jeffery M.; Nemeth, William; Wang, Qi; van Duin, Adri C. T.; Kim, Taek-Soo; Zheng, Xiaolin

    2013-10-01

    Peel-and-stick process, or water-assisted transfer printing (WTP), represents an emerging process for transferring fully fabricated thin-film electronic devices with high yield and fidelity from a SiO2/Si wafer to various non-Si based substrates, including papers, plastics and polymers. This study illustrates that the fundamental working principle of the peel-and-stick process is based on the water-assisted subcritical debonding, for which water reduces the critical adhesion energy of metal-SiO2 interface by 70 ~ 80%, leading to clean and high quality transfer of thin-film electronic devices. Water-assisted subcritical debonding is applicable for a range of metal-SiO2 interfaces, enabling the peel-and-stick process as a general and tunable method for fabricating flexible/transparent thin-film electronic devices.

  18. Peel-and-stick: mechanism study for efficient fabrication of flexible/transparent thin-film electronics.

    PubMed

    Lee, Chi Hwan; Kim, Jae-Han; Zou, Chenyu; Cho, In Sun; Weisse, Jeffery M; Nemeth, William; Wang, Qi; van Duin, Adri C T; Kim, Taek-Soo; Zheng, Xiaolin

    2013-10-10

    Peel-and-stick process, or water-assisted transfer printing (WTP), represents an emerging process for transferring fully fabricated thin-film electronic devices with high yield and fidelity from a SiO2/Si wafer to various non-Si based substrates, including papers, plastics and polymers. This study illustrates that the fundamental working principle of the peel-and-stick process is based on the water-assisted subcritical debonding, for which water reduces the critical adhesion energy of metal-SiO2 interface by 70 ~ 80%, leading to clean and high quality transfer of thin-film electronic devices. Water-assisted subcritical debonding is applicable for a range of metal-SiO2 interfaces, enabling the peel-and-stick process as a general and tunable method for fabricating flexible/transparent thin-film electronic devices.

  19. The significance of respiration timing in the energetics estimates of free-ranging killer whales (Orcinus orca).

    PubMed

    Roos, Marjoleine M H; Wu, Gi-Mick; Miller, Patrick J O

    2016-07-01

    Respiration rate has been used as an indicator of metabolic rate and associated cost of transport (COT) of free-ranging cetaceans, discounting potential respiration-by-respiration variation in O2 uptake. To investigate the influence of respiration timing on O2 uptake, we developed a dynamic model of O2 exchange and storage. Individual respiration events were revealed from kinematic data from 10 adult Norwegian herring-feeding killer whales (Orcinus orca) recorded with high-resolution tags (DTAGs). We compared fixed O2 uptake per respiration models with O2 uptake per respiration estimated through a simple 'broken-stick' O2-uptake function, in which O2 uptake was assumed to be the maximum possible O2 uptake when stores are depleted or maximum total body O2 store minus existing O2 store when stores are close to saturated. In contrast to findings assuming fixed O2 uptake per respiration, uptake from the broken-stick model yielded a high correlation (r(2)>0.9) between O2 uptake and activity level. Moreover, we found that respiration intervals increased and became less variable at higher swimming speeds, possibly to increase O2 uptake efficiency per respiration. As found in previous studies, COT decreased monotonically versus speed using the fixed O2 uptake per respiration models. However, the broken-stick uptake model yielded a curvilinear COT curve with a clear minimum at typical swimming speeds of 1.7-2.4 m s(-1) Our results showed that respiration-by-respiration variation in O2 uptake is expected to be significant. And though O2 consumption measurements of COT for free-ranging cetaceans remain impractical, accounting for the influence of respiration timing on O2 uptake will lead to more consistent predictions of field metabolic rates than using respiration rate alone. © 2016. Published by The Company of Biologists Ltd.

  20. 76 FR 28068 - Notice of Inventory Completion: Utah State University/College of Eastern Utah Prehistoric Museum...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-13

    ... pieces of leather (used to strap the wrapped infant to the stick cradle frame). In the 1960s, human... to 1971, human remains representing a minimum of six individuals were accidentally discovered during... maize cobs, 3 small pieces of cordage, 1 large twist/cache of dogbane fiber, 2 large pine cones, 1 bear...

  1. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Atutov, S. N., E-mail: atutovsn@mail.ru; Plekhanov, A. I.

    We present the results of a systematic study of Knudsen’s flow of Rb atoms in cylindrical capillary cells coated with a polydimethylsiloxane (PDMS) compound. The purpose of the investigation is to determine the characterization of the coating in terms of the sticking probability and sticking time of Rb on the two types of coating of high and medium viscosities. We report the measurement of the sticking probability of a Rb atom to the coating equal to 4.3 × 10{sup −5}, which corresponds to the number of bounces 2.3 × 10{sup 4} at room temperature. These parameters are the same formore » the two kinds of PDMS used. We find that at room temperature, the respective sticking times for high-viscosity and medium-viscosity PDMS are 22 ± 3 μs and 49 ± 6 μs. These sticking times are about million times larger than the sticking time derived from the surface Rb atom adsorption energy and temperature of the coating. A tentative explanation of this surprising result is proposed based on the bulk diffusion of the atoms that collide with the surface and penetrate inside the coating. The results can be important in many resonance cell experiments, such as the efficient magnetooptical trapping of rare elements or radioactive isotopes and in experiments on the light-induced drift effect.« less

  2. Ballasting pipeline moving in horizontal well as method of control sticking phenomenon

    NASA Astrophysics Data System (ADS)

    Toropov, V. S.; Toropov, E. S.

    2018-05-01

    The mechanism of the phenomenon of sticking a pipeline moving in a well while pulled by the facility horizontal directional drilling is investigated. A quantitative evaluation of the force arising from sticking is given. At the same time, the working hypothesis takes a view of the combined effect of adhesion and friction interactions as the reasons that cause this phenomenon. As a measure to control the occurrence of sticking and to reduce the resistance force to movement of the pipeline in the well, several methods of ballasting the working pipeline are proposed, depending on the profile of the well and the ratio of the length of the curved sections of the inlet and outlet and the straight horizontal sections of the profile. It is shown that for crossings, which profile contains an extended horizontal section, it is possible to partially fill the pipeline with water to achieve zero buoyancy, and for crossings with curvature along the entire profile, the ballasting efficiency will be minimal.

  3. New non-stick expoxy-silicone water-based coatings part 1: Physical and surface properties

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Garti, N.; Smith, J.

    In search for tomorrow`s technology for water-based coating, Decora Manufacturing and The Hebrew University of Jerusalem, have initiated an intensive research program for designing, developing and manufacturing new coatings based on cross-linked, room temperature-cured silicone-expoxy resins. The new water-borne coatings have most exciting characteristics such as: non-stick properties, effective release, high lubricity, corrosion protection and abrasion resistance. The coatings are environmentally-friendly and easy to use. These coatings are ideal for marine, agricultural, industrial and maintenance applications. This paper brings quantitative measurements related to the dispersion technology (particle size, stability, shelf-life), to the non-stick properties (deicing, low surface energy, easy-release andmore » non-stick), lubricity, adhesion to substrates, viscosity, dynamic and static friction coefficients and environmental impact (low VOC, non-toxicity, low-leaching). The coating was tested in various industrial coating systems and was found to exhibit excellent non-stick and release properties. Special attention was given to Zebra Mussels, Quagga Mussels and other bacterial and algeal bioforms. The coating proved to be efficient as foul-release coating with very low biofouling adhesion. The low adhesion applied to many other substances in which foul-release means easy-clean and low-wear.« less

  4. Influence of chlorhexidine on dentin adhesive interface micromorphology and nanoleakage expression of resin cements.

    PubMed

    Stape, Thiago Henrique Scarabello; Menezes, Murilo De Sousa; Barreto, Bruno De Castro Ferreira; Naves, Lucas Zago; Aguiar, Flávio Henrique Baggio; Quagliatto, Paulo Sérgio; Martins, Luís Roberto Marcondes

    2013-08-01

    This study focused on adhesive interface morphologic characterization and nanoleakage expression of resin cements bonded to human dentin pretreated with 1% chlorhexidine (CHX). Thirty-two non-carious human third molars were ground flat to expose superficial dentin. Resin composite blocks were luted to the exposed dentin using one conventional (RelyX ARC) and one self-adhesive resin cement (RelyX U100), with/without CHX pretreatment. Four groups (n = 8) were obtained: control groups (ARC and U100); experimental groups (ARC/CHX and U100/CHX) were pretreated with 1% CHX prior to the luting process. After storage in water for 24 h, the bonded teeth were sectioned into 0.9 × 0.9 mm(2) sticks producing a minimum of 12 sticks per tooth. Four sticks from each tooth were prepared for hybrid layer evaluation by scanning electron microscope analysis. The remaining sticks were immersed in silver nitrate for 24 h for either nanoleakage evaluation along the bonded interfaces or after rupture. Nanoleakage samples were carbon coated and examined using backscattered electron mode. Well-established hybrid layers were observed in the groups luted with RelyX ARC. Nanoleakage evaluation revealed increase nanoleakage in groups treated with CHX for both resin cements. Group U100/CHX exhibited the most pronouncing nanoleakage expression along with porous zones adjacent to the CHX pretreated dentin. The results suggest a possible incompatibility between CHX and RelyX U100 that raises the concern that the use of CHX with self-adhesive cements may adversely affect resin-dentin bond. Copyright © 2013 Wiley Periodicals, Inc.

  5. The Probability of Muon Sticking and X-Ray Yields in the Muon Catalyzed Fusion Cycle in a Deuterium and Tritium Mixture

    NASA Astrophysics Data System (ADS)

    Pahlavani, M. R.; Motevalli, S. M.

    2008-03-01

    The muon catalyzed fusion cycle in mixtures of deuterium and tritium is of particular interest due to the observation of high fusion yields. In the D-T mixture, the most serious limitation to the efficiency of the fusion chain is the probability of muon sticking to the alpha -particle produced in the nuclear reaction. An accurate kinetic treatment has been applied to the muonic helium atoms formed by a muon sticking to the alpha -particles. In this work accurate rates for collisions of alpha mu + ions with hydrogen atoms have been used for calculation of muon stripping probability and the intensities of X-ray transitions by solving a set of coupled differential equations numerically. Our calculated results are in good agreement with experimental data available in literature.

  6. Experimental Study of Reciprocating Friction between Rape Stalk and Bionic Nonsmooth Surface Units

    PubMed Central

    Ma, Zheng; Li, Yaoming; Xu, Lizhang

    2015-01-01

    Background. China is the largest producer of rape oilseed in the world; however, the mechanization level of rape harvest is relatively low, because rape materials easily adhere to the cleaning screens of combine harvesters, resulting in significant cleaning losses. Previous studies have shown that bionic nonsmooth surface cleaning screens restrain the adhesion of rape materials, but the underlying mechanisms remain unclear. Objective. The reciprocating friction between rape stalk and bionic nonsmooth metal surface was examined. Methods. The short-time Fourier transform method was used to discriminate the stable phase of friction signals and the stick-lag distance was defined to analyze the stable reciprocating friction in a phase diagram. Results. The reciprocating friction between rape stalk and metal surface is a typical stick-slip friction, and the bionic nonsmooth metal surfaces with concave or convex units reduced friction force with increasing reciprocating frequency. The results also showed that the stick-lag distance of convex surface increased with reciprocating frequency, which indicated that convex surface reduces friction force more efficiently. Conclusions. We suggest that bionic nonsmooth surface cleaning screens, especially with convex units, restrain the adhesion of rape materials more efficiently compared to the smooth surface cleaning screens. PMID:27034611

  7. On improving the efficiency of tensor voting.

    PubMed

    Moreno, Rodrigo; Garcia, Miguel Angel; Puig, Domenec; Pizarro, Luis; Burgeth, Bernhard; Weickert, Joachim

    2011-11-01

    This paper proposes two alternative formulations to reduce the high computational complexity of tensor voting, a robust perceptual grouping technique used to extract salient information from noisy data. The first scheme consists of numerical approximations of the votes, which have been derived from an in-depth analysis of the plate and ball voting processes. The second scheme simplifies the formulation while keeping the same perceptual meaning of the original tensor voting: The stick tensor voting and the stick component of the plate tensor voting must reinforce surfaceness, the plate components of both the plate and ball tensor voting must boost curveness, whereas junctionness must be strengthened by the ball component of the ball tensor voting. Two new parameters have been proposed for the second formulation in order to control the potentially conflictive influence of the stick component of the plate vote and the ball component of the ball vote. Results show that the proposed formulations can be used in applications where efficiency is an issue since they have a complexity of order O(1). Moreover, the second proposed formulation has been shown to be more appropriate than the original tensor voting for estimating saliencies by appropriately setting the two new parameters.

  8. The impact of automatic devices for capillary blood collection on efficiency and pain response in newborns: A randomized controlled trial.

    PubMed

    Sorrentino, G; Fumagalli, M; Milani, S; Cortinovis, I; Zorz, A; Cavallaro, G; Mosca, F; Plevani, L

    2017-07-01

    The heel stick is the method of choice in most neonatal units for capillary blood sampling, and it represents the most common event among all painful procedures performed on newborns. The type and design of heel stick device and the clinical procedure to collect a blood sample may have an impact on newborn pain response as well. To compare the pain response and efficiency of different automated devices for capillary blood collection in newborns. Randomized clinical trial. Postnatal ward of a tertiary-care university hospital in Italy. Newborn infants at gestational age ≥34 weeks undergoing the metabolic screening test after the 49th hour of life. A total of 762 neonates were recruited and randomized into 6 groups (127 babies in each group) assigned to 6 different capillary blood collection devices (Ames Minilet™ Lancet; Cardinal Health Gentleheel ® ; Natus Medical NeatNick™; BD Quikheel™ Lancet; Vitrex Steriheel ® Baby Lancet; Accriva Diagnostics Tenderfoot ® ). The following data were collected and assessed for each of the 6 groups evaluated: a) number of heel sticks, b) pain score according to the Neonatal Infant Pain Scale (NIPS) and c) need to squeeze the heel. The Ames Minilet™ Lancet device was found to perform by far the worst compared to the five device underexamination: it required the highest number of sticks (mean=3.91; 95% CI: 3.46-4.36), evoked the most intense pain (mean=3.98; 95% CI: 3.77-4.20), and most frequently necessitated squeezing the heel (92.9%; 95% CI: 86.9-96.3). The five devices under examination appeared to be similar in terms of the number of sticks required, but differed slightly in NIPS score and in need to squeeze the heel. The Accriva Diagnostics Tenderfoot ® device demonstrated the greatest efficiency for blood sampling and evoked the least pain. With this device, the metabolic screening test could be performed with a single skin incision in the large majority of infants (98.4%), heel squeezing was limited to only 6.3% of infants, and the NIPS score turns out to be lower than other devices in our study (1.22; 95% CI 1.05-1.39). Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Interactions of extracts from selected chewing stick sources with Aggregatibacter actinomycetemcomitans

    PubMed Central

    2012-01-01

    Background Aggregatibacter actinomycetemcomitans produces a leukotoxin that activates a pro-inflammatory death of human monocytes/macrophages. A specific clone of this bacterium (JP2) has a 530-base pair deletion in the leukotoxin promoter gene and significantly enhanced expression of leukotoxin. This specific clone of A. actinomycetemcomitans is common in some African populations and has a strong association with periodontal attachment loss in adolescents in these populations. Chewing sticks of plant origin are commonly used as oral hygiene tool in Africa, but their role as a therapeutic agent in periodontal disease is poorly investigated. Results Ethanol extracts were made from 7 common plants used as chewing sticks in West-Africa. None of the tested extracts inhibited growth of A. actinomycetemcomitans. However, extracts from Psidium guajava (Guava) completely neutralized the cell death and pro-inflammatory response of human leukocytes induced by the leukotoxin. None of the six other tested chewing stick extracts showed this effect. Conclusions The discovery that extracts from Guava efficiently neutralizes A. actinomycetemcomitans leukotoxicity might lead to novel therapeutic agents and strategies for prevention and treatment of aggressive forms of periodontitis induced by infections with the highly leukotoxic JP2 clone of this bacterium. PMID:22537711

  10. Hole filling with oriented sticks in ultrasound volume reconstruction

    PubMed Central

    Vaughan, Thomas; Lasso, Andras; Ungi, Tamas; Fichtinger, Gabor

    2015-01-01

    Abstract. Volumes reconstructed from tracked planar ultrasound images often contain regions where no information was recorded. Existing interpolation methods introduce image artifacts and tend to be slow in filling large missing regions. Our goal was to develop a computationally efficient method that fills missing regions while adequately preserving image features. We use directional sticks to interpolate between pairs of known opposing voxels in nearby images. We tested our method on 30 volumetric ultrasound scans acquired from human subjects, and compared its performance to that of other published hole-filling methods. Reconstruction accuracy, fidelity, and time were improved compared with other methods. PMID:26839907

  11. Denitrification-Efficiencies of Alternate Carbon Sources

    DTIC Science & Technology

    1984-07-01

    carbon source evaluated, while sweet whey, corn steep liquor , acid whey and soluble potato solids followed in order of decreasing efficiency. Three of...denitrification and total organic carbon removal with ’I. sweet whey 11 3. Percent denitrification and total organic carbon removal with corn steep liquor ...and total organic carbon removal with hydrolyzed sludge 18 10. Percent denitrification and total organic carbon removal with fish stick 19 11

  12. Investigation of Positron Sticking to the Surfaces of Topological Insulators

    NASA Astrophysics Data System (ADS)

    Shastry, K.; Joglekar, P. V.; Olenga, A. Y.; Fazleev, N. G.; Weiss, A. H.; Barniellini, B.

    2013-03-01

    We describe experiments aimed at probing the sticking of positrons to the surfaces of topological insulators. In these experiments, a magnetically beam will be used to deposit positrons at the surface of Bi2Te2Se. The energy spectra and intensities of electrons emitted as a result of Positron Annihilation induced Auger electron Spectroscopy (PAES) provides a distinct element specific signal which can be used to determine if positrons can be trapped efficiently into a surface localized bound state. The experiments are aimed at determining the practicality of using positron annihilation to selectively probe the critically important top most layer of topological insulator system. Welch Y1100, NSF DMR 0907679

  13. Assessment of indoor pollutants generated from bio and synthetic fuels in selected villages of Burdwan, West Bengal.

    PubMed

    Mondal, N K; Bhaumik, R; Das, C R; Aditya, P; Datta, J K; Banerjee, A; Das, K

    2013-09-01

    The objective of the present study was to access the pollutant generated from bio-fuels like bamboo sticks, cow dung, paddy straw, carbon dust cake, gobar gas, jute stick, and mustard stick and synthetic fuel like LPG during cooking in rural villages of Burdwan, West Bengal, India and its fluctuation in living room. The average SO2 released from the fuels was found in the following order: bamboo stick > cow dung > paddy straw > carbon cake > gobar gas > jute stick > LPG > mustard stick; NO2 emission was in the following order : mustard stick > carbon dust cake > paddy straw > cow dung cake > LPG, jute stick > gobar gas > bamboo stick > and SPM was obtained in the following sequence: cow dung cake > bamboo stick > carbon dust cake > gobar gas > LPG > mustard stick > paddy straw > jute stick, respectively. The highest living room to kitchen room (L/K) ratio of SO2, NO, and SPM was found in LPG, gobar gas, jute stick respectively in 2009 and followed by bamboo stick > paddy straw > jute stick > cow dung cake, respectively in 2010. Results of this study suggest that different fuels released different amount of air pollutants, but more extensive study is needed to confirm the relationship between fuels and released air pollutants.

  14. Foreshocks during the nucleation of stick-slip instability

    USGS Publications Warehouse

    McLaskey, Gregory C.; Kilgore, Brian D.

    2013-01-01

    We report on laboratory experiments which investigate interactions between aseismic slip, stress changes, and seismicity on a critically stressed fault during the nucleation of stick-slip instability. We monitor quasi-static and dynamic changes in local shear stress and fault slip with arrays of gages deployed along a simulated strike-slip fault (2 m long and 0.4 m deep) in a saw cut sample of Sierra White granite. With 14 piezoelectric sensors, we simultaneously monitor seismic signals produced during the nucleation phase and subsequent dynamic rupture. We observe localized aseismic fault slip in an approximately meter-sized zone in the center of the fault, while the ends of the fault remain locked. Clusters of high-frequency foreshocks (Mw ~ −6.5 to −5.0) can occur in this slowly slipping zone 5–50 ms prior to the initiation of dynamic rupture; their occurrence appears to be dependent on the rate at which local shear stress is applied to the fault. The meter-sized nucleation zone is generally consistent with theoretical estimates, but source radii of the foreshocks (2 to 70 mm) are 1 to 2 orders of magnitude smaller than the theoretical minimum length scale over which earthquake nucleation can occur. We propose that frictional stability and the transition between seismic and aseismic slip are modulated by local stressing rate and that fault sections, which would typically slip aseismically, may radiate seismic waves if they are rapidly stressed. Fault behavior of this type may provide physical insight into the mechanics of foreshocks, tremor, repeating earthquake sequences, and a minimum earthquake source dimension.

  15. Intra- and intersegmental influences among central pattern generating networks in the walking system of the stick insect.

    PubMed

    Mantziaris, Charalampos; Bockemühl, Till; Holmes, Philip; Borgmann, Anke; Daun, Silvia; Büschges, Ansgar

    2017-10-01

    To efficiently move around, animals need to coordinate their limbs. Proper, context-dependent coupling among the neural networks underlying leg movement is necessary for generating intersegmental coordination. In the slow-walking stick insect, local sensory information is very important for shaping coordination. However, central coupling mechanisms among segmental central pattern generators (CPGs) may also contribute to this. Here, we analyzed the interactions between contralateral networks that drive the depressor trochanteris muscle of the legs in both isolated and interconnected deafferented thoracic ganglia of the stick insect on application of pilocarpine, a muscarinic acetylcholine receptor agonist. Our results show that depressor CPG activity is only weakly coupled between all segments. Intrasegmental phase relationships differ between the three isolated ganglia, and they are modified and stabilized when ganglia are interconnected. However, the coordination patterns that emerge do not resemble those observed during walking. Our findings are in line with recent studies and highlight the influence of sensory input on coordination in slowly walking insects. Finally, as a direct interaction between depressor CPG networks and contralateral motoneurons could not be observed, we hypothesize that coupling is based on interactions at the level of CPG interneurons. NEW & NOTEWORTHY Maintaining functional interleg coordination is vitally important as animals locomote through changing environments. The relative importance of central mechanisms vs. sensory feedback in this process is not well understood. We analyzed coordination among the neural networks generating leg movements in stick insect preparations lacking phasic sensory feedback. Under these conditions, the networks governing different legs were only weakly coupled. In stick insect, central connections alone are thus insufficient to produce the leg coordination observed behaviorally. Copyright © 2017 the American Physiological Society.

  16. 16 CFR 1507.10 - Rockets with sticks.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Rockets with sticks. 1507.10 Section 1507.10... FIREWORKS DEVICES § 1507.10 Rockets with sticks. Rockets with sticks (including skyrockets and bottle rockets) shall utilize a straight and rigid stick to provide a direct and stable flight. Such sticks shall...

  17. 16 CFR 1507.10 - Rockets with sticks.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Rockets with sticks. 1507.10 Section 1507.10... FIREWORKS DEVICES § 1507.10 Rockets with sticks. Rockets with sticks (including skyrockets and bottle rockets) shall utilize a straight and rigid stick to provide a direct and stable flight. Such sticks shall...

  18. 16 CFR 1507.10 - Rockets with sticks.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Rockets with sticks. 1507.10 Section 1507.10... FIREWORKS DEVICES § 1507.10 Rockets with sticks. Rockets with sticks (including skyrockets and bottle rockets) shall utilize a straight and rigid stick to provide a direct and stable flight. Such sticks shall...

  19. 16 CFR 1507.10 - Rockets with sticks.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Rockets with sticks. 1507.10 Section 1507.10... FIREWORKS DEVICES § 1507.10 Rockets with sticks. Rockets with sticks (including skyrockets and bottle rockets) shall utilize a straight and rigid stick to provide a direct and stable flight. Such sticks shall...

  20. Relating stick-slip friction experiments to earthquake source parameters

    USGS Publications Warehouse

    McGarr, Arthur F.

    2012-01-01

    Analytical results for parameters, such as static stress drop, for stick-slip friction experiments, with arbitrary input parameters, can be determined by solving an energy-balance equation. These results can then be related to a given earthquake based on its seismic moment and the maximum slip within its rupture zone, assuming that the rupture process entails the same physics as stick-slip friction. This analysis yields overshoots and ratios of apparent stress to static stress drop of about 0.25. The inferred earthquake source parameters static stress drop, apparent stress, slip rate, and radiated energy are robust inasmuch as they are largely independent of the experimental parameters used in their estimation. Instead, these earthquake parameters depend on C, the ratio of maximum slip to the cube root of the seismic moment. C is controlled by the normal stress applied to the rupture plane and the difference between the static and dynamic coefficients of friction. Estimating yield stress and seismic efficiency using the same procedure is only possible when the actual static and dynamic coefficients of friction are known within the earthquake rupture zone.

  1. Fatigue effects upon sticking region and electromyography in a six-repetition maximum bench press.

    PubMed

    van den Tillaar, Roland; Saeterbakken, Atle Hole

    2013-01-01

    The aim of the study was to examine the sticking region and concomitant neuromuscular activation of the prime movers during six-repetition maximum (RM) bench pressing. We hypothesised that both peak velocities would decrease and that the electromyography (EMG) of the prime movers (deltoid, major pectoralis and triceps) would increase during the pre-sticking and sticking region during the six repetitions due to fatigue. Thirteen resistance-trained males (age 22.8 ± 2.2 years, stature 1.82 ± 0.06 m, body mass 83.4 ± 7.6 kg) performed 6-RM bench presses. Barbell kinematics and EMG activity of pectoralis major, deltoid anterior, and triceps brachii during the pre-, sticking and post-sticking region of each repetition in a 6-RM bench press were analysed. For both the sticking as the post-sticking region, the time increased significantly from the first to the sixth repetition. Vertical barbell height at the start of sticking region was lower, while the height at the end of the sticking region and post-sticking region did not change during the six repetitions. It was concluded that in 6-RM bench pressing performance, the sticking region is a poor mechanical force region due to the unchanged barbell height at the end of the sticking region. Furthermore, when fatigue occurs, the pectoralis and the deltoid muscles are responsible for surpassing the sticking region as indicated by their increased activity during the pre- and sticking region during the six-repetitions bench press.

  2. Effects of stick design features on perceptions of characteristics of cigarettes.

    PubMed

    Borland, Ron; Savvas, Steven

    2013-09-01

    To examine the extent (if any) that cigarette stick dimension, tipping paper design and other decorative design/branding have on Australian smokers' perceptions of those cigarettes. An internet survey of 160 young Australian adult ever-smokers who were shown computer images of three sets of cigarette sticks--five sticks of different lengths and diameters (set A), five sticks with different tipping paper design (set B) and four sticks of different decorative design (set C). Branding was a between-subjects randomised condition for set C. For each set, respondents ranked sticks on most and least attractive, highest and lowest quality and strongest and weakest taste. Cigarette sticks were perceived as different on attractiveness, quality and strength of taste. Standard stick length/diameter was perceived as the most attractive and highest quality stick, with men more inclined to rate a slim stick as less attractive. A stick with a cork-patterned tipping paper and a gold band was seen as most attractive, of highest quality and strongest in taste compared to other tipping designs. Branded sticks were seen as more attractive, higher in quality and stronger tasting than non-branded designs, regardless of brand, although the effects were stronger for a prestige compared with a budget brand. Characteristics of the cigarette stick affect smokers' perceptions of the attributes of those cigarettes and thus are a potential means by which product differentiation can occur. A comprehensive policy to eliminate promotional aspects of cigarette design and packaging needs to include rules about stick design.

  3. Comparison of hiking stick use on lateral stability while balancing with and without a load.

    PubMed

    Jacobson, B H; Caldwell, B; Kulling, F A

    1997-08-01

    To compare hiking stick use on lateral stability while balancing with or without a load (15-kg internal frame backpack) under conditions of no stick, 1 stick, and 2 sticks for six trials 15 volunteers ages 19 to 23 years (M = 21.7 yr.) were tested six separate times on a stability platform. During randomly ordered, 1-min. trials, the length of time (sec.) the subject maintained balance (+/-10 degrees of horizontal) and the number of deviations beyond 10 degrees were recorded simultaneously. Backpack and hiking sticks were individually adjusted for each subject. A 2 x 3 repeated factor analysis of variance indicated that subjects balanced significantly longer both with and without a load while using 2 hiking sticks than 1 or 0 sticks. Significantly fewer deviations beyond 10 degrees were found when subjects were without a load and using 1 or 2 sticks versus when they used none, and no significant difference in the number of deviations were found between 1 and 2 hiking sticks. When subjects were equipped with a load, significantly improved balance was found only between the 2 sticks and no sticks. Balance was significantly enhanced by using hiking sticks, and two sticks were more effective than one while carrying a load. An increase in maintenance of static balance may reduce the possibility of falling and injury while standing on loose alpine terrain.

  4. Unraveling complexities of velocity dependent retention and release parameters for E. coli in saturated porous media

    USDA-ARS?s Scientific Manuscript database

    Escherichia coli transport and release experiments were conducted to investigate the pore-water velocity (v) dependency of the sticking efficiency (a), the fraction of the solid surface area that contributed to retention (Sf), the percentage of injected cells that were irreversibly retained (Mirr), ...

  5. Thick tellurium target preparation by vacuum deposition

    NASA Astrophysics Data System (ADS)

    Stolarz, Anna

    1999-12-01

    Tellurium targets of thickness up to 6.5 mg/cm 2 on carbon backings were prepared by vacuum deposition. The influence of the crucible dimension, treatment of the backing foil by glow discharge and substrate cooling on the Te sticking efficiency was studied in order to achieve the best yield.

  6. E-2633

    NASA Image and Video Library

    1956-10-12

    A photo of the control stick used on the Iron Cross Attitude Simulator. Although it resembled today's desktop computer flight sticks, its operation was different. As with a standard control stick, moving it back and forth raised and lowered the nose resulting in changes in pitch. Moving the stick to the right or left raised or lowered the wing, resulted in changes in roll. This control stick had a third axis, not found in standard control sticks. Twisting the stick to the right or left caused the airplane's nose to move horizontally in the same direction, resulting in changes in yaw.

  7. Langley Full-Scale Tunnel Investigation of a 1/3-Scale Model of the Chance Vought XF5U-1 Airplane

    NASA Technical Reports Server (NTRS)

    Lange, Roy H.; Cocke, Bennie W., Jr.; Proterra, Anthony J.

    1946-01-01

    The results of an investigation of a 1/3-scale model of the Chance Vought XF5U-1 airplane in the Langley full-scale tunnel are presented in this report. The maximum lift and stalling characteristics of several model configurations, the longitudinal stability characteristics of the model, and the effectiveness of the control surfaces were determined with the propellers removed. The propulsive characteristics, the effect of propeller operation on the lift, and the static thrust of the model propellers were determined at several propeller-blade angles. The results with the propellers removed showed that the maximum lift coefficient of the complete model configuration was only 0.97 was compared with the value of 1.31 for the model configuration in which the engine-air ducts and canopy are removed. The model with the propellers removed (normal center-of-gravity position) has a positive static margin, stick fixed, varying from 5 to 13 percent of the mean aerodynamic chord throughout the unstalled range of lift coefficients. The unit horizontal tail is sufficiently powerful to trim the airplane with the propellers removed throughout the unstalled range of lift coefficients. The peak propulsive efficiencies for beta = 20 degrees and beta = 30 degrees were increased 7 percent at C(sub L) congruent to 0.67 and 20 percent at C(sub L) congruent to 0.74, respectively, with the propellers rotating upward in the center than with the propellers rotating downward in the center. Indications are that the minimum forward-flight speed of the airplane for full-power operation at sea level will be about 90 miles per hour. Decreasing the weight and increasing the power reduced this value of minimum speed and there were no indications from the results of a lower limit to the minimum speed.

  8. Powder properties and compaction parameters that influence punch sticking propensity of pharmaceuticals.

    PubMed

    Paul, Shubhajit; Taylor, Lisa J; Murphy, Brendan; Krzyzaniak, Joseph F; Dawson, Neil; Mullarney, Matthew P; Meenan, Paul; Sun, Changquan Calvin

    2017-04-15

    Punch sticking is a frequently occurring problem that challenges successful tablet manufacturing. A mechanistic understanding of the punch sticking phenomenon facilitates the design of effective strategies to solve punch sticking problems of a drug. The first step in this effort is to identify process parameters and particle properties that can profoundly affect sticking performance. This work was aimed at elucidating the key material properties and compaction parameters that influence punch sticking by statistically analyzing punch sticking data of 24 chemically diverse compounds obtained using a set of tooling with removable upper punch tip. Partial least square (PLS) analysis of the data revealed that particle surface area and tablet tensile strength are the most significant factors attributed to punch sticking. Die-wall pressure, ejection force, and take-off force also correlate with sticking, but to a lesser extent. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. 16 CFR § 1507.10 - Rockets with sticks.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Rockets with sticks. § 1507.10 Section Â... REGULATIONS FIREWORKS DEVICES § 1507.10 Rockets with sticks. Rockets with sticks (including skyrockets and bottle rockets) shall utilize a straight and rigid stick to provide a direct and stable flight. Such...

  10. Development of an ash particle deposition model considering build-up and removal mechanisms

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kjell Strandstroem; Christian Muellera; Mikko Hupa

    2007-12-15

    Slagging and fouling on heat exchanger surfaces in power boilers fired with fossil fuels and fuel mixtures has a significant influence on boiler efficiency and availability. Mathematical modelling has long been considered a suitable method to assist boiler operators to determine optimized operating conditions for an existing furnace. The ultimate goal in ash deposition prediction is hereby the determination of the total amount of material deposited and hence the determination of the total reduction in efficiency. Depending on the fuels fired the total deposited mass is a combination of ash particle deposition and ash particle erosion due to non-sticky particles.more » The novel ash particle deposition model presented in this work considers deposition of sticky ash particles, cleansing of deposit by non-sticky sand particles and sticking of sand due to contact with sticky ash. The steady-state modelling results for the total amount of ash deposited on the deposition probe of an entrained flow reactor presented in this work agree well with the experimental data. Only at very high fractions of sand added as non-sticky material, a significant influence of the sand on the overall mass deposited was found. Since the model considers sticking of non-sticking sand due to contact with sticky ash, the fraction of sand deposited on the probe was especially studied. Using a correction factor to consider the influence of operating time on the steady-state simulations led to good agreement between simulations and experimental data. 12 refs., 10 figs.« less

  11. Deposition and re-erosion studies by means of local impurity injection in TEXTOR

    NASA Astrophysics Data System (ADS)

    Textor Team Kirschner, A.; Kreter, A.; Wienhold, P.; Brezinsek, S.; Coenen, J. W.; Esser, H. G.; Pospieszczyk, A.; Schulz, Ch.; Breuer, U.; Borodin, D.; Clever, M.; Ding, R.; Galonska, A.; Huber, A.; Litnovsky, A.; Matveev, D.; Ohya, K.; Philipps, V.; Samm, U.; Schmitz, O.; Schweer, B.; Stoschus, H.

    2011-08-01

    Pioneering experiments to study local erosion and deposition processes have been carried out in TEXTOR by injecting 13C marked hydrocarbons (CH4 and C2H4) as well as silane (SiD4) and tungsten-hexafluoride (WF6) through test limiters exposed to the edge plasma. The influence of various limiter materials (C, W, Mo) and surface roughness, different geometries (spherical or roof-like) and local plasma parameters has been studied. Depending on these conditions the local deposition efficiency of injected species varies between 0.1% and 9% - the largest deposition has been found for 13CH4 injection through unpolished, spherical C test limiter and ohmic plasma conditions. The most striking result is that ERO modelling cannot reproduce these low deposition efficiencies using the common assumptions on sticking probabilities and physical and chemical re-erosion yields. As an explanation large re-erosion due to background plasma and possibly low "effective sticking" of returning species is applied. This has been interpreted as enhanced re-erosion of re-deposits under simultaneous impact of high ion fluxes from plasma background.

  12. Preliminary design study of a lateral-directional control system using thrust vectoring

    NASA Technical Reports Server (NTRS)

    Lallman, F. J.

    1985-01-01

    A preliminary design of a lateral-directional control system for a fighter airplane capable of controlled operation at extreme angles of attack is developed. The subject airplane is representative of a modern twin-engine high-performance jet fighter, is equipped with ailerons, rudder, and independent horizontal-tail surfaces. Idealized bidirectional thrust-vectoring engine nozzles are appended to the mathematic model of the airplane to provide additional control moments. Optimal schedules for lateral and directional pseudo control variables are calculated. Use of pseudo controls results in coordinated operation of the aerodynamic and thrust-vectoring controls with minimum coupling between the lateral and directional airplane dynamics. Linear quadratic regulator designs are used to specify a preliminary flight control system to improve the stability and response characteristics of the airplane. Simulated responses to step pilot control inputs are stable and well behaved. For lateral stick deflections, peak stability axis roll rates are between 1.25 and 1.60 rad/sec over an angle-of-attack range of 10 deg to 70 deg. For rudder pedal deflections, the roll rates accompanying the sideslip responses can be arrested by small lateral stick motions.

  13. The Single Cigarette Economy in India--a Back of the Envelope Survey to Estimate its Magnitude.

    PubMed

    Lal, Pranay; Kumar, Ravinder; Ray, Shreelekha; Sharma, Narinder; Bhattarcharya, Bhaktimay; Mishra, Deepak; Sinha, Mukesh K; Christian, Anant; Rathinam, Arul; Singh, Gurbinder

    2015-01-01

    Sale of single cigarettes is an important factor for early experimentation, initiation and persistence of tobacco use and a vital factor in the smoking epidemic in India as it is globally. Single cigarettes also promote the sale of illicit cigarettes and neutralises the effect of pack warnings and effective taxation, making tobacco more accessible and affordable to minors. This is the first study to our knowledge which estimates the size of the single stick market in India. In February 2014, a 10 jurisdiction survey was conducted across India to estimate the sale of cigarettes in packs and sticks, by brands and price over a full business day. We estimate that nearly 75% of all cigarettes are sold as single sticks annually, which translates to nearly half a billion US dollars or 30 percent of the India's excise revenues from all cigarettes. This is the price which the consumers pay but is not captured through tax and therefore pervades into an informal economy. Tracking the retail price of single cigarettes is an efficient way to determine the willingness to pay by cigarette smokers and is a possible method to determine the tax rates in the absence of any other rationale.

  14. Effect of video-game experience and position of flight stick controller on simulated-flight performance.

    PubMed

    Cho, Bo-Keun; Aghazadeh, Fereydoun; Al-Qaisi, Saif

    2012-01-01

    The purpose of this study was to determine the effects of video-game experience and flight-stick position on flying performance. The study divided participants into 2 groups; center- and side-stick groups, which were further divided into high and low level of video-game experience subgroups. The experiment consisted of 7 sessions of simulated flying, and in the last session, the flight stick controller was switched to the other position. Flight performance was measured in terms of the deviation of heading, altitude, and airspeed from their respective requirements. Participants with high experience in video games performed significantly better (p < .001) than the low-experienced group. Also, participants performed significantly better (p < .001) with the center-stick than the side-stick. When the side-stick controller was switched to the center-stick position, performance scores continued to increase (0.78 %). However, after switching from a center- to a side-stick controller, performance scores decreased (4.8%).

  15. Vacuum MOCVD fabrication of high efficience cells

    NASA Technical Reports Server (NTRS)

    Partain, L. D.; Fraas, L. M.; Mcleod, P. S.; Cape, J. A.

    1985-01-01

    Vacuum metal-organic-chemical-vapor-deposition (MOCVD) is a new fabrication process with improved safety and easier scalability due to its metal rather than glass construction and its uniform multiport gas injection system. It uses source materials more efficiently than other methods because the vacuum molecular flow conditions allow the high sticking coefficient reactants to reach the substrates as undeflected molecular beams and the hot chamber walls cause the low sticking coefficient reactants to bounce off the walls and interact with the substrates many times. This high source utilization reduces the materials costs power device and substantially decreases the amounts of toxic materials that must be handled as process effluents. The molecular beams allow precise growth control. With improved source purifications, vacuum MOCVD has provided p GaAs layers with 10-micron minority carrier diffusion lengths and GaAs and GaAsSb solar cells with 20% AMO efficiencies at 59X and 99X sunlight concentration ratios. Mechanical stacking has been identified as the quickest, most direct and logical path to stacked multiple-junction solar cells that perform better than the best single-junction devices. The mechanical stack is configured for immediate use in solar arrays and allows interconnections that improve the system end-of-life performance in space.

  16. On relating apparent stress to the stress causing earthquake fault slip

    USGS Publications Warehouse

    McGarr, A.

    1999-01-01

    Apparent stress ??a is defined as ??a = ??????, where ???? is the average shear stress loading the fault plane to cause slip and ?? is the seismic efficiency, defined as Ea/W, where Ea is the energy radiated seismically and W is the total energy released by the earthquake. The results of a recent study in which apparent stresses of mining-induced earthquakes were compared to those measured for laboratory stick-slip friction events led to the hypothesis that ??a/???? ??? 0.06. This hypothesis is tested here against a substantially augmented data set of earthquakes for which ???? can be estimated, mostly from in situ stress measurements, for comparison with ??a. The expanded data set, which includes earthquakes artificially triggered at a depth of 9 km in the German Kontinentales Tiefbohrprogramm der Bundesrepublik Deutschland (KTB) borehole and natural tectonic earthquakes, covers a broad range of hypocentral depths, rock types, pore pressures, and tectonic settings. Nonetheless, over ???14 orders of magnitude in seismic moment, apparent stresses exhibit distinct upper bounds defined by a maximum seismic efficiency of ???0.06, consistent with the hypothesis proposed before. This behavior of ??a and ?? can be expressed in terms of two parameters measured for stick-slip friction events in the laboratory: the ratio of the static to the dynamic coefficient of friction and the fault slip overshoot. Typical values for these two parameters yield seismic efficiencies of ???0.06. In contrast to efficiencies for laboratory events for which ?? is always near 0.06, those for earthquakes tend to be less than this bounding value because Ea for earthquakes is usually underestimated due to factors such as band-limited recording. Thus upper bounds on ??a/???? appear to be controlled by just a few fundamental aspects of frictional stick-slip behavior that are common to shallow earthquakes everywhere. Estimates of ???? from measurements of ??a for suites of earthquakes, using ??a/???? ??? 0.06, are found to be comparable in magnitude to estimates of shear stress on the basis of extrapolating in situ stress data to seismogenic depths.

  17. Comparison of Single-Stick and Double-Stick Techniques for Percutaneous Nephrostomy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Funaki, Brian, E-mail: bfunaki@midway.uchicago.edu; Vatakencherry, Geogi

    2004-01-15

    We compared single- and double-stick techniques of percutaneous nephrostomy insertion by retrospectively reviewing 140 percutaneous nephrostomy procedures in 101 patients. All procedures were performed by residents or fellows with direct attending supervision. Either the single-stick or double-stick technique was used based solely on personal attending preference. There were no significant differences in groups in terms of age, sex, or degree of hydronephrosis. In the single-stick technique, the kidney was punctured with sonographic guidance and the tract was serially dilated to accept an 8.5 Fr. nephrostomy catheter. In the double-stick technique, the kidney was punctured with sonographic guidance and a mixturemore » of air and contrast were injected into the collecting system. The affected side was then elevated and a posterior calyx was punctured using fluoroscopic guidance. Both groups were compared in terms of complications and early tube dysfunction using the chi-squared test. All procedures were successful without immediate complications. Bleeding requiring transfusion occurred in 4.7% (4/86) procedures in the single stick group and 3.7% (2/54) in the double stick group (p-value not significant). None of these patients required further interventions for bleeding. Tube dysfunction leading to premature tube exchange occurred in 3.5% (3/86) of catheters in the single stick group and 3.7% (2/54) of catheters in the double- stick group (p-value not significant). We found no significant difference between the single and double- stick methods of percutaneous nephrostomy in terms of success rates, complications, or tube function. We believe that the single-stick method should be adopted as the insertion technique of choice.« less

  18. Modeling stick-slip-separation dynamics in a bimodal standing wave ultrasonic motor

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Yao, Zhiyuan; Lv, Qibao; Liu, Zhen

    2016-11-01

    Ultrasonic motor (USM) is an electromechanical coupling system with ultrasonic vibration, which is driven by the frictional contact force between the stator (vibrating body) and the rotor/slider (driven body). Stick-slip motion can occur at the contact interface when USM is operating, which may affect the performance of the motor. This paper develops a physically-based model to investigate the complex stick-slip-separation dynamics in a bimodal standing wave ultrasonic motor. The model includes both friction nonlinearity and intermittent separation nonlinearity of the system. Utilizing Hamilton's principle and assumed mode method, the dynamic equations of the stator are deduced. Based on the dynamics of the stator and the slider, sticking force during the stick phase is derived, which is used to examine the stick-to-slip transition. Furthermore, the stick-slip-separation kinematics is analyzed by establishing analytical criteria that predict the transition between stick, slip and separation of the interface. Stick-slip-separation motion is observed in the resulting model, and numerical simulations are performed to study the influence of parameters on the range of possible motions. Results show that stick-slip motion can occur with greater preload and smaller voltage amplitude. Furthermore, a dimensionless parameter is proposed to predict the occurrence of stick-slip versus slip-separation motions, and its role in designing ultrasonic motors is discussed. It is shown that slip-separation motion is favorable for the slider velocity.

  19. Stick-weaving: Innovative Behavior in Tamarins

    PubMed Central

    Snowdon, Charles T.; Roskos, Thomas R.

    2017-01-01

    Some captive cotton-top tamarins spontaneously weave sticks in the mesh of their enclosures so that the stick is lodged between two mesh openings. Sticks are broken from natural branches placed in the enclosures and often modified by biting them in the center before weaving through the mesh. To investigate this further we systematically surveyed all animals in our colony and found that all successful stick weaving tamarins were descendants from only two of the 16 breeding groups contributing to the colony membership at the time of surveying or were the mates of these descendants, suggesting stick-weaving is a socially learned behavior. Successful stick-weavers were presented with pipe cleaners, soda straws and wooden dowels to see if they would generalize stick-weaving to novel objects. Seven of 10 animals successfully wove with straws or pipe cleaners showing that they could generalize the behavior to objects that were physically different but had the same affordances as the sticks. Data from a father-daughter pair suggest a form of coaching. Innovative behavior is needed for the emergence of culture with subsequent social transmission. Although innovative behavior in primates is mainly associated with foraging and is more likely to occur among males, stick-weaving has no obvious reward and appeared equally in both sexes. Stick-weaving behavior and its probable social transmission across generations suggest the possibility of cultural traditions emerging in this species. PMID:28277719

  20. The "sticking period" in a maximum bench press.

    PubMed

    van den Tillaar, Roland; Ettema, Gertjan

    2010-03-01

    The purpose of this study was to examine muscle activity and three-dimensional kinematics in the ascending phase of a successful one-repetition maximum attempt in bench press for 12 recreational weight-training athletes, with special attention to the sticking period. The sticking period was defined as the first period of deceleration of the upward movement (i.e. from the highest barbell velocity until the first local lowest barbell velocity). All participants showed a sticking period during the upward movement that started about 0.2 s after the initial upward movement, and lasted about 0.9 s. Electromyography revealed that the muscle activity of the prime movers changed significantly from the pre-sticking to the sticking and post-sticking periods. A possible mechanism for the existence of the sticking period is the diminishing potentiation of the contractile elements during the upward movement together with the limited activity of the pectoral and deltoid muscles during this period.

  1. Pneumatic strength assessment device: design and isometric measurement.

    PubMed

    Paulus, David C; Reiser, Raoul F; Troxell, Wade O

    2004-01-01

    In order to load a muscle optimally during resistance exercise, it should be heavily taxed throughout the entire range of motion for that exercise. However, traditional constant resistance squats only tax the lower-extremity muscles to their limits at the "sticking region" or a critical joint configuration of the exercise cycle. Therefore, a linear motion (Smith) exercise machine was modified with pneumatics and appropriate computer control so that it could be capable of adjusting force to control velocity within a repetition of the squat exercise or other exercise performed with the device. Prior to application of this device in a dynamic squat setting, the maximum voluntary isometric force (MVIF) produced over a spectrum of knee angles is needed. This would reveal the sticking region and overall variation in strength capacity. Five incremental knee angles (90, 110, 130, 150, and 170 degrees, where 180 degrees defined full extension) were examined. After obtaining university-approved informed consent, 12 men and 12 women participated in the study. The knee angle was set, and the pneumatic cylinder was pressurized such that the subject could move the barbell slightly but no more than two-centimeters. The peak pressure exerted over a five-second maximum effort interval was recorded at each knee angle in random order and then repeated. The average of both efforts was then utilized for further analysis. The sticking region occurred consistently at a 90 degrees knee angle, however, the maximum force produced varied between 110 degrees and 170 degrees with the greatest frequency at 150 degrees for both men and women. The percent difference between the maximum and minimum MVIF was 46% for men and 57% for women.

  2. Modeling of combustion processes of stick propellants via combined Eulerian-Lagrangian approach

    NASA Technical Reports Server (NTRS)

    Kuo, K. K.; Hsieh, K. C.; Athavale, M. M.

    1988-01-01

    This research is motivated by the improved ballistic performance of large-caliber guns using stick propellant charges. A comprehensive theoretical model for predicting the flame spreading, combustion, and grain deformation phenomena of long, unslotted stick propellants is presented. The formulation is based upon a combined Eulerian-Lagrangian approach to simulate special characteristics of the two phase combustion process in a cartridge loaded with a bundle of sticks. The model considers five separate regions consisting of the internal perforation, the solid phase, the external interstitial gas phase, and two lumped parameter regions at either end of the stick bundle. For the external gas phase region, a set of transient one-dimensional fluid-dynamic equations using the Eulerian approach is obtained; governing equations for the stick propellants are formulated using the Lagrangian approach. The motion of a representative stick is derived by considering the forces acting on the entire propellant stick. The instantaneous temperature and stress fields in the stick propellant are modeled by considering the transient axisymmetric heat conduction equation and dynamic structural analysis.

  3. A new paradigm for human stick balancing: a suspended not an inverted pendulum.

    PubMed

    Lee, Kwee-Yum; O'Dwyer, Nicholas; Halaki, Mark; Smith, Richard

    2012-09-01

    We studied 14 skilled subjects balancing a stick (a television antenna, 52 cm, 34 g) on their middle fingertip. Comprehensive three-dimensional analyses revealed that the movement of the finger was 1.75 times that of the stick tip, such that the balanced stick behaved more like a normal noninverted pendulum than the inverted pendulum common to engineering models for stick balancing using motors. The average relation between the torque applied to the stick and its angle of deviation from the vertical was highly linear, consistent with simple harmonic motion. We observed clearly greater rotational movement of the stick in the anteroposterior plane than the mediolateral plane. Despite this magnitude difference, the duration of stick oscillatory cycles was very similar in both planes, again consistent with simple harmonic motion. The control parameter in balancing was the ratio of active torque applied to the stick relative to gravitational torque. It determined both the pivot point and oscillatory cycle period of the pendulum. The pivot point was located at the radius of gyration (about the centre of mass) of the stick from its centre of mass, showing that the subjects attuned to the gravitational dynamics and mass distribution of the stick. Hence, the key to controlling instability here was mastery of the physics of the unstable object. The radius of gyration may--similar to centre of mass--contribute to the kinesthesis of rotating limb segments and control of their gravitational dynamics.

  4. Weathering effects on fuel moisture sticks: corrections and recommendations.

    Treesearch

    Donald A. Haines; John S. Frost

    1978-01-01

    Describes response to weathering of 100-gram (1/2-inch) fuel moisture sticks over 6-month fire season in the Northeast. Presents a chart for correcting weathered-stick values and gives replacement recommendations for those sticks used in the National Fire Danger Rating System.

  5. Numerical simulation of temperature at drilling micro-hole on moving CO2 laser irradiated sticking plaster

    NASA Astrophysics Data System (ADS)

    Rao, Zhiming; He, Zhifang; Du, Jianqiang; Zhang, Xinyou; Ai, Guoping; Zhang, Chunqiang; Wu, Tao

    2012-03-01

    This paper applied numerical simulation of temperature by using finite element analysis software Ansys to study a model of drilling on sticking plaster. The continuous CO2 laser doing uniform linear motion and doing uniform circular motion irradiated sticking plaster to vaporize. The sticking plaster material was chosen as the thermal conductivity, the heat capacity and the density. For temperatures above 450 °C, sticking plaster would be vaporized. Based on the mathematical model of heat transfer, the process of drilling sticking plaster by laser beams could be simulated by Ansys. The simulation results showed the distribution of the temperature at the surface of the sticking plaster with the time of vaporizing at CO2 laser to do uniform linear motion and to do uniform circular motion. The temperature of sticking plaster CO2 laser to do uniform linear motion was higher than CO2 laser to do uniform circular motion in the same condition.

  6. The Effect of Aerosols on Pluto's C2 Hydrocarbon Chemistry

    NASA Astrophysics Data System (ADS)

    Luspay-Kuti, Adrienn; Mandt, Kathleen; Jessup, Kandis-Lea; Hue, Vincent; Kammer, Joshua; Filwett, Rachael; Hamel, Mark

    2017-10-01

    On July 14, 2015 the New Horizons spacecraft flew through the Pluto system, providing critical details about Pluto’s atmosphere. The vertical profiles of N2 and CH4, C2H2, C2H4, and C2H6 derived from New Horizons Alice transmission data allow the more accurate modeling of Pluto’s atmosphere than in the pre-New Horizons era, and help better understand the physical and photochemical processes in Pluto’s atmosphere. All the measured C2 hydrocarbon densities showed an unexpected inversion between ~100 and 400 km, which suggests that processes other than chemistry play an important role in shaping their vertical profiles. We present here a state-of-the-art Pluto Ion-Neutral-Photochemistry (Pluto INP) model that includes the condensation onto and incorporation into aerosol particles, and evaluate the dominant production and loss processes of C2 hydrocarbons with a special emphasis on the role of aerosol interaction. We found that in order to reproduce the C2 profiles measured by New Horizons, they must stick to and be permanently removed by aerosols - a process different from condensation. We determined through empirical fits to the New Horizons data that the sticking efficiency of C2 hydrocarbons and the stickiness of the aerosol particles are inversely related to the available aerosol surface area, which has been inferred from observation to increase as altitude decreases. This counterintuitive relationship between sticking efficiency and available aerosol surfaces indicates that similarly to Titan, Pluto’s aerosols must harden and become less sticky as they age. Such hardening with ageing is both necessary and sufficient to explain the vertical profiles of C2 hydrocarbons in Pluto’s atmosphere.

  7. Popsicle-Stick Cobra Wave

    NASA Astrophysics Data System (ADS)

    Boucher, Jean-Philippe; Clanet, Christophe; Quéré, David; Chevy, Frédéric

    2017-08-01

    The cobra wave is a popular physical phenomenon arising from the explosion of a metastable grillage made of popsicle sticks. The sticks are expelled from the mesh by releasing the elastic energy stored during the weaving of the structure. Here we analyze both experimentally and theoretically the propagation of the wave front depending on the properties of the sticks and the pattern of the mesh. We show that its velocity and its shape are directly related to the recoil imparted to the structure by the expelled sticks. Finally, we show that the cobra wave can only exist for a narrow range of parameters constrained by gravity and rupture of the sticks.

  8. Serrated kiln sticks and top load substantially reduce warp in southern pine studs dried at 240°F

    Treesearch

    Peter Koch

    1974-01-01

    Sharply toothed aluminum kiln sticks pressed into 2 by 4's cut from veneer cores, with a clamping force of 50 to 200 pounds per stick-pair per stud, significantly reduced warp from that observed in matched studs stacked on smooth sticks with a top load of 10 pounds per stick-pair per stud. When dried in 24 hours to an average MC of 8.1 percent (standard deviation...

  9. Serrated kiln sticks and top load substantially reduce warp in southern pine studs dried at 240°F

    Treesearch

    P. Koch

    1974-01-01

    Sharply toothed luminum kiln sticks pressed into 2 by 4's cut from veneer cores, willi a clamping force of 50 to 200 pounds per stick-pair per stud, significantly reduced warp from that observed in matched studs stacked on smooth sticks with a top load of 10 pounds per stick-pair per stud. When dried in 24 hours to an average MC of 8.1 percent (standard deviation...

  10. Positive selection in glycolysis among Australasian stick insects

    PubMed Central

    2013-01-01

    Background The glycolytic pathway is central to cellular energy production. Selection on individual enzymes within glycolysis, particularly phosphoglucose isomerase (Pgi), has been associated with metabolic performance in numerous organisms. Nonetheless, how whole energy-producing pathways evolve to allow organisms to thrive in different environments and adopt new lifestyles remains little explored. The Lanceocercata radiation of Australasian stick insects includes transitions from tropical to temperate climates, lowland to alpine habitats, and winged to wingless forms. This permits a broad investigation to determine which steps within glycolysis and what sites within enzymes are the targets of positive selection. To address these questions we obtained transcript sequences from seven core glycolysis enzymes, including two Pgi paralogues, from 29 Lanceocercata species. Results Using maximum likelihood methods a signature of positive selection was inferred in two core glycolysis enzymes. Pgi and Glyceraldehyde 3-phosphate dehydrogenase (Gaphd) genes both encode enzymes linking glycolysis to the pentose phosphate pathway. Positive selection among Pgi paralogues and orthologues predominately targets amino acids with residues exposed to the protein’s surface, where changes in physical properties may alter enzyme performance. Conclusion Our results suggest that, for Lancerocercata stick insects, adaptation to new stressful lifestyles requires a balance between maintaining cellular energy production, efficiently exploiting different energy storage pools and compensating for stress-induced oxidative damage. PMID:24079656

  11. Gamma irradiation and steam pretreatment of jute stick powder for the enhancement of dye adsorption efficiency

    NASA Astrophysics Data System (ADS)

    Parvin, Fahmida; Sultana, Nargis; Habib, S. M. Ahsan; Bhoumik, Nikhil Chandra

    2017-11-01

    The aim of this study is to find out the facile and effective pretreatment technique to enhance the capacity of jute stick powder (JSP) in adsorbing dye from raw textile effluent. Hence, different pretreatment techniques, i.e., radiation treatment, alkali treatment, ammonia treatment, steam treatment and CaCl2 treatment were applied to JSP and the adsorbing performance were examined for synthetic dye solutions (Blue FCL and Red RL dye). Different gamma radiation doses were applied on JSP and optimum dye removal efficiency was found at 500 krad in removing these two dyes (50 ppm) from solutions. Among the different pretreatment techniques, gamma irradiated JSP (500 Krad) exhibits highest dye uptake capacity for RED RL dye, whereas steam-treated JSP shows highest performance in adsorbing blue FCL dye. Subsequently, we applied the gamma irradiated and steam-treated JSP on real textile effluent (RTE) and these two techniques shows potentiality in adsorbing dye from raw textile effluent and in reducing BOD5, COD load and TOC to some extent as well. Fourier transform infrared spectroscopy (FTIR) analysis also proved that dye has been adsorbed on pretreated JSP.

  12. Gray Wolf (Canis lupus) death by stick impalement

    USGS Publications Warehouse

    Barber-Meyer, Shannon; Schmidt, Lori; Mech, L. David

    2017-01-01

    Although Canis lupus L. (Gray Wolf) individuals are sometimes impaled by sticks, we could find no documentation of natural impalement by sticks as a cause of death for wild Wolves. Here we report on a wild Gray Wolf from northeastern Minnesota that died due to stick puncture of its thorax and abdomen.

  13. Evaluation of Two Unique Side Stick Controllers in a Fixed-Base Flight Simulator

    NASA Technical Reports Server (NTRS)

    Mayer, Jann; Cox, Timothy H.

    2003-01-01

    A handling qualities analysis has been performed on two unique side stick controllers in a fixed-base F-18 flight simulator. Each stick, which uses a larger range of motion than is common for similar controllers, has a moving elbow cup that accommodates movement of the entire arm for control. The sticks are compared to the standard center stick in several typical fighter aircraft tasks. Several trends are visible in the time histories, pilot ratings, and pilot comments. The aggressive pilots preferred the center stick, because the side sticks are underdamped, causing overshoots and oscillations when large motions are executed. The less aggressive pilots preferred the side sticks, because of the smooth motion and low breakout forces. The aggressive pilots collectively gave the worst ratings, probably because of increased sensitivity of the simulator (compared to the actual F-18 aircraft), which can cause pilot-induced oscillations when aggressive inputs are made. Overall, the elbow cup is not a positive feature, because using the entire arm for control inhibits precision. Pilots had difficulty measuring their performance, particularly during the offset landing task, and tended to overestimate.

  14. Numerical analysis for the stick-slip vibration of a transversely moving beam in contact with a frictional wall

    NASA Astrophysics Data System (ADS)

    Won, Hong-In; Chung, Jintai

    2018-04-01

    This paper presents a numerical analysis for the stick-slip vibration of a transversely moving beam, considering both stick-slip transition and friction force discontinuity. The dynamic state of the beam was separated into the stick state and the slip state, and boundary conditions were defined for both. By applying the finite element method, two matrix-vector equations were derived: one for stick state and the other for slip state. However, the equations have different degrees of freedom depending on whether the end of a beam sticks or slips, so we encountered difficulties in time integration. To overcome the difficulties, we proposed a new numerical technique to alternatively use the matrix-vector equations with different matrix sizes. In addition, to eliminate spurious high-frequency responses, we applied the generalized-α time integration method with appropriate value of high-frequency numerical dissipation. Finally, the dynamic responses of stick-slip vibration were analyzed in time and frequency domains: the dynamic behavior of the beam was explained to facilitate understanding of the stick-slip motion, and frequency characteristics of the stick-slip vibration were investigated in relation to the natural frequencies of the beam. The effects of the axial load and the moving speed upon the dynamic response were also examined.

  15. Quality changes of fresh-cut kohlrabi sticks under modified atmosphere packaging.

    PubMed

    Escalona, V H; Aguayo, E; Artés, F

    2007-06-01

    The aim of this study was to determine the effect of different gas compositions on quality attributes and shelf life of kohlrabi sticks stored in modified atmosphere up to 14 d at 0 degrees C. Two commercial films were tested: oriented polypropylene (OPP) and amide-polyethylene (amide-PE). As a control, a microperforated OPP film was used. In order to study the changes in metabolic activity by minimal processing, the respiration rate and ethylene production at 0 degrees C were monitored for both intact stems and sticks. Changes in color, chemical parameters, sugars and organic acid contents, and sensorial quality of kohlrabi sticks were evaluated. An initial ethylene production of sticks was 13-fold higher than that of intact stems; meanwhile CO(2) production was 2-fold higher. However after 4 d of storage, a similar respiration rate for stems and sticks was found. Also the ethylene production of sticks and stems was steady around 15 to 20 nL/kg(/)h after 10 d. Kohlrabi sticks showed a little change in chemical parameters and very low weight losses during cold storage. Sticks under an equilibrium atmosphere of 7 kPa O(2) and 9 kPa CO(2) at 0 degrees C reached by amide-PE kept an acceptable sensorial quality for 14 d.

  16. Stick-slip friction and wear of articular joints

    PubMed Central

    Lee, Dong Woog; Banquy, Xavier; Israelachvili, Jacob N.

    2013-01-01

    Stick-slip friction was observed in articular cartilage under certain loading and sliding conditions and systematically studied. Using the Surface Forces Apparatus, we show that stick-slip friction can induce permanent morphological changes (a change in the roughness indicative of wear/damage) in cartilage surfaces, even under mild loading and sliding conditions. The different load and speed regimes can be represented by friction maps—separating regimes of smooth and stick-slip sliding; damage generally occurs within the stick-slip regimes. Prolonged exposure of cartilage surfaces to stick-slip sliding resulted in a significant increase of surface roughness, indicative of severe morphological changes of the cartilage superficial zone. To further investigate the factors that are conducive to stick-slip and wear, we selectively digested essential components of cartilage: type II collagen, hyaluronic acid (HA), and glycosaminoglycans (GAGs). Compared with the normal cartilage, HA and GAG digestions modified the stick-slip behavior and increased surface roughness (wear) during sliding, whereas collagen digestion decreased the surface roughness. Importantly, friction forces increased up to 2, 10, and 5 times after HA, GAGs, and collagen digestion, respectively. Also, each digestion altered the friction map in different ways. Our results show that (i) wear is not directly related to the friction coefficient but (ii) more directly related to stick-slip sliding, even when present at small amplitudes, and that (iii) the different molecular components of joints work synergistically to prevent wear. Our results also suggest potential noninvasive diagnostic tools for sensing stick-slip in joints. PMID:23359687

  17. Experiments on vibration-driven stick-slip locomotion: A sliding bifurcation perspective

    NASA Astrophysics Data System (ADS)

    Du, Zhouwei; Fang, Hongbin; Zhan, Xiong; Xu, Jian

    2018-05-01

    Dry friction appears at the contact interface between two surfaces and is the source of stick-slip vibrations. Instead of being a negative factor, dry friction is essential for vibration-driven locomotion system to take effect. However, the dry-friction-induced stick-slip locomotion has not been fully understood in previous research, especially in terms of experiments. In this paper, we experimentally study the stick-slip dynamics of a vibration-driven locomotion system from a sliding bifurcation perspective. To this end, we first design and build a vibration-driven locomotion prototype based on an internal piezoelectric cantilever. By utilizing the mechanical resonance, the small piezoelectric deformation is significantly amplified to drive the prototype to achieve effective locomotion. Through identifying the stick-slip characteristics in velocity histories, we could categorize the system's locomotion into four types and obtain a stick-slip categorization diagram. In each zone of the diagram the locomotion exhibits qualitatively different stick-slip dynamics. Such categorization diagram is actually a sliding bifurcation diagram; crossing from one stick-slip zone to another corresponds to the triggering of a sliding bifurcation. In addition, a simplified single degree-of-freedom model is established, with the rationality of simplification been explained theoretically and numerically. Based on the equivalent model, a numerical stick-slip categorization is also obtained, which shows good agreement with the experiments both qualitatively and quantitatively. To the best of our knowledge, this is the first work that experimentally generates a sliding bifurcation diagram. The obtained stick-slip categorizations deepen our understanding of stick-slip dynamics in vibration-driven systems and could serve as a base for system design and optimization.

  18. Comment on "The Predicted Size of Cycle 23 Based on the Inferred three-cycle Quasiperiodicity of the Planetary Index Ap"

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.; Hathaway, David H.

    1999-01-01

    Recently, Ahluwalia reviewed the solar and geomagnetic data for the last 6 decades and remarked that these data "indicate the existence of a three-solar-activity-cycle quasiperiodicity in them." Furthermore, on the basis of this inferred quasiperiodicity, he asserted that cycle 23 represents the initial cycle in a new three-cycle string, implying that it "will be more modest (a la cycle 17) with an annual mean sunspot number count of 119.3 +/- 30 at the maximum", a prediction that is considerably below the consensus prediction of 160 +/- 30 by Joselin et al. and of similar predictions by others based on a variety of predictive techniques. Several major sticking points of Ahluwalia's presentation, however, must be readdressed, and these issues form the basis of this comment. First, Ahluwalia appears to have based his analysis on a data set of Ap index values that is erroneous. For example, he depicts for the interval of 1932-1997 the variation of the Ap index in terms of annual averages, contrasting them against annual averages of sunspot number (SSN), and he lists for cycles 17-23 the minimum and maximum value of each, as well as the years in which they occur and a quantity which he calls "Amplitude" (defined as the numeric difference between the maximum and minimum values). In particular, he identifies the minimum Ap index (i.e., the minimum value of the Ap index in the vicinity of sunspot cycle minimum, which usually occurs in the year following sunspot minimum and which will be called hereafter, simply, Ap min) and the year in which it occur for cycles 17 - 23 respectively.

  19. Horizontal Gene Transfer of Pectinases from Bacteria Preceded the Diversification of Stick and Leaf Insects

    PubMed Central

    Shelomi, Matan; Danchin, Etienne G. J.; Heckel, David; Wipfler, Benjamin; Bradler, Sven; Zhou, Xin; Pauchet, Yannick

    2016-01-01

    Genes acquired by horizontal transfer are increasingly being found in animal genomes. Understanding their origin and evolution requires knowledge about the phylogenetic relationships from both source and recipient organisms. We used RNASeq data and respective assembled transcript libraries to trace the evolutionary history of polygalacturonase (pectinase) genes in stick insects (Phasmatodea). By mapping the distribution of pectinase genes on a Polyneoptera phylogeny, we identified the transfer of pectinase genes from known phasmatodean gut microbes into the genome of an early euphasmatodean ancestor that took place between 60 and 100 million years ago. This transfer preceded the rapid diversification of the suborder, enabling symbiont-free pectinase production that would increase the insects’ digestive efficiency and reduce dependence on microbes. Bacteria-to-insect gene transfer was thought to be uncommon, however the increasing availability of large-scale genomic data may change this prevailing notion. PMID:27210832

  20. Glow Sticks: Spectra and Color Mixing

    NASA Astrophysics Data System (ADS)

    Birriel, Jennifer; Birriel, Ignacio

    2014-10-01

    Glow sticks are a popular Halloween staple familiar to most of our students. The production of light via a chemical reaction is called "chemiluminescence," and glow sticks are often used as demonstrations and experiments in the chemistry classroom to study reaction rates as a function of temperature.1-3 A black light can be used to illuminate glow sticks that have not been cracked or those that are "dead" in order to demonstrate fluorescence in liquid chemicals.4 In this article, we present the use of glow sticks as an inexpensive demonstration of spectra and color addition.

  1. Cigarette stick as valuable communicative real estate: a content analysis of cigarettes from 14 low-income and middle-income countries

    PubMed Central

    C Smith, Katherine; Washington, Carmen; Welding, Kevin; Kroart, Laura; Osho, Adami; Cohen, Joanna E

    2017-01-01

    Background The current cigarette market is heavily focused on low-income and middle-income countries. Branding of tobacco products is key to establishing and maintaining a customer base. Greater restrictions on marketing and advertising of tobacco products create an incentive for companies to focus more on branding via the product itself. We consider how tobacco sticks are used for communicative purposes in 14 low-income and middle-income countries with extensive tobacco markets. Methods In 2013, we collected and coded 3232 cigarette and kretek packs that were purchased from vendors in diverse neighbourhoods in 44 cities across the 14 low-income and middle-income countries with the greatest number of smokers. A single stick from each pack was assessed for branding, decorative and communicative elements using a common coding framework. Stick communication variables included brand name, brand image/logo, brand descriptor, colour and design carried through from pack, ‘capsule cigarette’ symbol, and embellishment of filter end. Results Communication and branding on the stick is essentially ubiquitous (99.75%); 97% of sticks include explicit branding (brand name or logo present). Colour is commonly carried through from the pack (95%), and some sticks (13%) include decorative elements matching the pack. Decorative elements can be found anywhere on the stick, including the filter tip (8%), and ‘convertible’ cigarettes include a symbol to show where to push. Conclusions Cigarette sticks are clearly valuable ‘real estate’ that tobacco companies are using for communicative purposes. Across all countries and brands, the stick communicates branding via text, colour and imagery. PMID:27534777

  2. Sticking of Molecules on Nonporous Amorphous Water Ice

    NASA Astrophysics Data System (ADS)

    He, Jiao; Acharyya, Kinsuk; Vidali, Gianfranco

    2016-05-01

    Accurate modeling of physical and chemical processes in the interstellar medium (ISM) requires detailed knowledge of how atoms and molecules adsorb on dust grains. However, the sticking coefficient, a number between 0 and 1 that measures the first step in the interaction of a particle with a surface, is usually assumed in simulations of ISM environments to be either 0.5 or 1. Here we report on the determination of the sticking coefficient of H2, D2, N2, O2, CO, CH4, and CO2 on nonporous amorphous solid water. The sticking coefficient was measured over a wide range of surface temperatures using a highly collimated molecular beam. We showed that the standard way of measuring the sticking coefficient—the King-Wells method—leads to the underestimation of trapping events in which there is incomplete energy accommodation of the molecule on the surface. Surface scattering experiments with the use of a pulsed molecular beam are used instead to measure the sticking coefficient. Based on the values of the measured sticking coefficient, we suggest a useful general formula of the sticking coefficient as a function of grain temperature and molecule-surface binding energy. We use this formula in a simulation of ISM gas-grain chemistry to find the effect of sticking on the abundance of key molecules both on grains and in the gas phase.

  3. STICKING OF MOLECULES ON NONPOROUS AMORPHOUS WATER ICE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    He, Jiao; Vidali, Gianfranco; Acharyya, Kinsuk, E-mail: gvidali@syr.edu

    2016-05-20

    Accurate modeling of physical and chemical processes in the interstellar medium (ISM) requires detailed knowledge of how atoms and molecules adsorb on dust grains. However, the sticking coefficient, a number between 0 and 1 that measures the first step in the interaction of a particle with a surface, is usually assumed in simulations of ISM environments to be either 0.5 or 1. Here we report on the determination of the sticking coefficient of H{sub 2}, D{sub 2}, N{sub 2}, O{sub 2}, CO, CH{sub 4}, and CO{sub 2} on nonporous amorphous solid water. The sticking coefficient was measured over a widemore » range of surface temperatures using a highly collimated molecular beam. We showed that the standard way of measuring the sticking coefficient—the King–Wells method—leads to the underestimation of trapping events in which there is incomplete energy accommodation of the molecule on the surface. Surface scattering experiments with the use of a pulsed molecular beam are used instead to measure the sticking coefficient. Based on the values of the measured sticking coefficient, we suggest a useful general formula of the sticking coefficient as a function of grain temperature and molecule-surface binding energy. We use this formula in a simulation of ISM gas–grain chemistry to find the effect of sticking on the abundance of key molecules both on grains and in the gas phase.« less

  4. 21 CFR 102.45 - Fish sticks or portions made from minced fish.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Fish sticks or portions made from minced fish. 102... for Specific Nonstandardized Foods § 102.45 Fish sticks or portions made from minced fish. (a) The common or usual name of the food product that resembles and is of the same composition as fish sticks or...

  5. 21 CFR 102.45 - Fish sticks or portions made from minced fish.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Fish sticks or portions made from minced fish. 102... for Specific Nonstandardized Foods § 102.45 Fish sticks or portions made from minced fish. (a) The common or usual name of the food product that resembles and is of the same composition as fish sticks or...

  6. 21 CFR 102.45 - Fish sticks or portions made from minced fish.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Fish sticks or portions made from minced fish. 102... for Specific Nonstandardized Foods § 102.45 Fish sticks or portions made from minced fish. (a) The common or usual name of the food product that resembles and is of the same composition as fish sticks or...

  7. 21 CFR 102.45 - Fish sticks or portions made from minced fish.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Fish sticks or portions made from minced fish. 102... for Specific Nonstandardized Foods § 102.45 Fish sticks or portions made from minced fish. (a) The common or usual name of the food product that resembles and is of the same composition as fish sticks or...

  8. Standard Methodology for Assessment of Range of Motion While Wearing Body Armor

    DTIC Science & Technology

    2013-09-30

    8 Figure 14: Meter stick (with close up...the tester to place against the measurement scale. A variety of rulers, meter sticks (Figure 14), and T square rulers (Figure 15) were used as well...All rulers and meter sticks had cm and mm marks on them. Figure 12: 20 cm block Figure 13: Measuring block Figure 14: Meter stick

  9. The existence of a sticking region in free weight squats.

    PubMed

    van den Tillaar, Roland; Andersen, Vidar; Saeterbakken, Atle Hole

    2014-09-29

    The aim of this study was to investigate the existence of the sticking region in two legged free weight squats. Fifteen resistance-training males (age 24 ± 4 years, body mass 82 ± 11 kg, body height 179 ± 6 cm) with 6 ± 3 years of resistance-training experience performed 6-RM in free weight squats. The last repetition was analyzed for the existence of a sticking region. Only in 10 out of 15 participants a sticking region was observed. The observed sticking region was much shorter than in the bench press. Furthermore, rectus femoris decreased the EMG activity in contrast to increased EMG activity in biceps femoris around the sticking and surrounding region. No significant change in EMG activity was found for the lateral and medial vastus muscles. It is suggested that a combination of these muscle activity changes could be one of the causes of the existence of the sticking region in free weight squats.

  10. The Existence of a Sticking Region in Free Weight Squats

    PubMed Central

    van den Tillaar, Roland; Andersen, Vidar; Saeterbakken, Atle Hole

    2014-01-01

    The aim of this study was to investigate the existence of the sticking region in two legged free weight squats. Fifteen resistance-training males (age 24 ± 4 years, body mass 82 ± 11 kg, body height 179 ± 6 cm) with 6 ± 3 years of resistance-training experience performed 6-RM in free weight squats. The last repetition was analyzed for the existence of a sticking region. Only in 10 out of 15 participants a sticking region was observed. The observed sticking region was much shorter than in the bench press. Furthermore, rectus femoris decreased the EMG activity in contrast to increased EMG activity in biceps femoris around the sticking and surrounding region. No significant change in EMG activity was found for the lateral and medial vastus muscles. It is suggested that a combination of these muscle activity changes could be one of the causes of the existence of the sticking region in free weight squats. PMID:25414740

  11. Cyclic control stick

    DOEpatents

    Whitaker, Charles N.; Zimmermann, Richard E.

    1989-01-01

    A cyclic control stick of the type used in helicopters for reducing the safety hazards associated with such a mechanism in the event of a crewman being thrown violently into contact with the cyclic control stick resulting from a crash or the like. The cyclic control stick is configured to break away upon the exertion of an impact force which exceeds a predetermined value and/or is exerted for more than a momentary time duration. The cyclic control stick is also configured to be adjustable so as to locate the grip thereof as far away from the crewman as possible for safety reasons without comprising the comfort of the crewman or the use of the control stick, and a crushable pad is provided on the top of the grip for impact energy absorbing purposes.

  12. The equivalence of minimum entropy production and maximum thermal efficiency in endoreversible heat engines.

    PubMed

    Haseli, Y

    2016-05-01

    The objective of this study is to investigate the thermal efficiency and power production of typical models of endoreversible heat engines at the regime of minimum entropy generation rate. The study considers the Curzon-Ahlborn engine, the Novikov's engine, and the Carnot vapor cycle. The operational regimes at maximum thermal efficiency, maximum power output and minimum entropy production rate are compared for each of these engines. The results reveal that in an endoreversible heat engine, a reduction in entropy production corresponds to an increase in thermal efficiency. The three criteria of minimum entropy production, the maximum thermal efficiency, and the maximum power may become equivalent at the condition of fixed heat input.

  13. Carrots and Sticks: A Comprehensive Business Model for the Successful Achievement of Energy Efficiency Resource Standards Environmental Energy Technologies DivisionMarch 2011

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Satchwell, Andrew; Cappers, Peter; Goldman, Charles

    2011-03-22

    Energy efficiency resource standards (EERS) are a prominent strategy to potentially achieve rapid and aggressive energy savings goals in the U.S. As of December 2010, twenty-six U.S. states had some form of an EERS with savings goals applicable to energy efficiency (EE) programs paid for by utility customers. The European Union has initiated a similar type of savings goal, the Energy End-use Efficiency and Energy Services Directive, where it is being implemented in some countries through direct partnership with regulated electric utilities. U.S. utilities face significant financial disincentives under traditional regulation which affects the interest of shareholders and managers inmore » aggressively pursuing cost-effective energy efficiency. Regulators are considering some combination of mandated goals ('sticks') and alternative utility business model components ('carrots' such as performance incentives) to align the utility's business and financial interests with state and federal energy efficiency public policy goals. European countries that have directed their utilities to administer EE programs have generally relied on non-binding mandates and targets; in the U.S., most state regulators have increasingly viewed 'carrots' as a necessary condition for successful achievement of energy efficiency goals and targets. In this paper, we analyze the financial impacts of an EERS on a large electric utility in the State of Arizona using a pro-forma utility financial model, including impacts on utility earnings, customer bills and rates. We demonstrate how a viable business model can be designed to improve the business case while retaining sizable ratepayer benefits. Quantifying these concerns and identifying ways they can be addressed are crucial steps in gaining the support of major stakeholder groups - lessons that can apply to other countries looking to significantly increase savings targets that can be achieved from their own utility-administered EE programs.« less

  14. Tetrahedra and Their Nets: Mathematical and Pedagogical Implications

    ERIC Educational Resources Information Center

    Mussa, Derege Haileselassie

    2013-01-01

    If one has three sticks (lengths), when can you make a triangle with the sticks? As long as any two of the lengths sum to a value strictly larger than the third length one can make a triangle. Perhaps surprisingly, if one is given 6 sticks (lengths) there is no simple way of telling if one can build a tetrahedron with the sticks. In fact, even…

  15. Cigarette stick as valuable communicative real estate: a content analysis of cigarettes from 14 low-income and middle-income countries.

    PubMed

    C Smith, Katherine; Washington, Carmen; Welding, Kevin; Kroart, Laura; Osho, Adami; Cohen, Joanna E

    2016-09-01

    The current cigarette market is heavily focused on low-income and middle-income countries. Branding of tobacco products is key to establishing and maintaining a customer base. Greater restrictions on marketing and advertising of tobacco products create an incentive for companies to focus more on branding via the product itself. We consider how tobacco sticks are used for communicative purposes in 14 low-income and middle-income countries with extensive tobacco markets. In 2013, we collected and coded 3232 cigarette and kretek packs that were purchased from vendors in diverse neighbourhoods in 44 cities across the 14 low-income and middle-income countries with the greatest number of smokers. A single stick from each pack was assessed for branding, decorative and communicative elements using a common coding framework. Stick communication variables included brand name, brand image/logo, brand descriptor, colour and design carried through from pack, 'capsule cigarette' symbol, and embellishment of filter end. Communication and branding on the stick is essentially ubiquitous (99.75%); 97% of sticks include explicit branding (brand name or logo present). Colour is commonly carried through from the pack (95%), and some sticks (13%) include decorative elements matching the pack. Decorative elements can be found anywhere on the stick, including the filter tip (8%), and 'convertible' cigarettes include a symbol to show where to push. Cigarette sticks are clearly valuable 'real estate' that tobacco companies are using for communicative purposes. Across all countries and brands, the stick communicates branding via text, colour and imagery. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  16. Dissuasive cigarette sticks: the next step in standardised ('plain') packaging?

    PubMed

    Hoek, Janet; Gendall, Philip; Eckert, Christine; Louviere, Jordan

    2016-11-01

    Standardised (or 'plain') packaging has reduced the appeal of smoking by removing imagery that smokers use to affiliate themselves with the brand they smoke. We examined whether changing the appearance of cigarette sticks could further denormalise smoking and enhance the negative impact of standardised packaging. We conducted an online study of 313 New Zealand smokers who comprised a Best-Worst Choice experiment and a rating task. The Best-Worst experiment used a 2×3×3×6 orthogonal design to test the following attributes: on-pack warning message, branding level, warning size and stick appearance. We identified three segments whose members' choice patterns were strongly influenced by the stick design, warning theme and size, and warning theme, respectively. Each of the dissuasive sticks tested was less preferred and rated as less appealing than the most common stick in use; a 'minutes of life lost' stick was the most aversive of the stimuli tested. Dissuasive sticks could enhance the effect of standardised packaging, particularly among older smokers who are often more heavily addicted and resistant to change. Countries introducing standardised packaging legislation should take the opportunity to denormalise the appearance of cigarette sticks, in addition to removing external tobacco branding from packs and increasing the warning size. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  17. The effects of an exercise with a stick on the lumbar spine and hip movement patterns during forward bending in patients with lumbar flexion syndrome.

    PubMed

    Yoon, Ji-yeon; Kim, Ji-won; Kang, Min-hyeok; An, Duk-hyun; Oh, Jae-seop

    2015-01-01

    Forward bending is frequently performed in daily activities. However, excessive lumbar flexion during forward bending has been reported as a risk factor for low back pain. Therefore, we examined the effects of an exercise strategy using a stick on the angular displacement and movement onset of lumbar and hip flexion during forward-bending exercises in patients with lumbar flexion syndrome. Eighteen volunteers with lumbar flexion syndrome were recruited in this study. Subjects performed forward-bending exercises with and without a straight stick in standing. The angular displacement and movement onset of lumbar and hip flexion during forward-bending exercises were measured by using a three dimensional motion analysis system. The significances of differences between the two conditions (with stick vs. without stick) was assessed using a one-way repeated analysis of variance. When using a stick during a forward-bending exercise, the peak angular displacement of lumbar flexion decreased significantly, and those of right and left-hip flexion increased significantly compared with those without a stick. The movement onset of lumbar flexion occurred significantly later, and the onset of right-hip flexion occurred significantly earlier with than without a stick. Based on these findings, a stick exercise was an effective method to prevent excessive lumbar flexion and more helpful in developing hip flexion during a forward-bending exercise. These findings will be useful for clinicians to teach self-exercise during forward bending in patients with lumbar flexion syndrome.

  18. Task-specific modulation of adult humans' tool preferences: number of choices and size of the problem.

    PubMed

    Silva, Kathleen M; Gross, Thomas J; Silva, Francisco J

    2015-03-01

    In two experiments, we examined the effect of modifications to the features of a stick-and-tube problem on the stick lengths that adult humans used to solve the problem. In Experiment 1, we examined whether people's tool preferences for retrieving an out-of-reach object in a tube might more closely resemble those reported with laboratory crows if people could modify a single stick to an ideal length to solve the problem. Contrary to when adult humans have selected a tool from a set of ten sticks, asking people to modify a single stick to retrieve an object did not generally result in a stick whose length was related to the object's distance. Consistent with the prior research, though, the working length of the stick was related to the object's distance. In Experiment 2, we examined the effect of increasing the scale of the stick-and-tube problem on people's tool preferences. Increasing the scale of the task influenced people to select relatively shorter tools than had selected in previous studies. Although the causal structures of the tasks used in the two experiments were identical, their results were not. This underscores the necessity of studying physical cognition in relation to a particular causal structure by using a variety of tasks and methods.

  19. Development of a New Punch Head Shape to Replicate Scale-Up Issues on a Laboratory Tablet Press III: Replicating sticking phenomenon using the SAS punch and evaluation by checking the tablet surface using 3D laser scanning microscope.

    PubMed

    Ito, Manabu; Aoki, Shigeru; Uchiyama, Jumpei; Yamato, Keisuke

    2018-04-20

    Sticking is a common observation in the scale-up stage on the punch tip using a commercial tableting machine. The difference in the total compression time between a laboratory and a commercial tableting machine is considered one of the main root causes of scale up issues in the tableting processes. The proposed Size Adjusted for Scale-up (SAS) punch can be used to adjust the consolidation and dwell times for commercial tableting machine. As a result, the sticking phenomenon is able to be replicated at the pilot scale stage. As reported in this paper, the quantification of sticking was measured using a 3D laser scanning microscope to check the tablet surface. It was shown that the sticking area decreased with the addition of magnesium stearate in the formulation, but the sticking depth was not affected by the additional amount of magnesium stearate. It is proposed that use of a 3D laser scanning microscope can be applied to evaluate sticking as a process analytical technology (PAT) tool and so sticking can be monitored continuously without stopping the machine. Copyright © 2018. Published by Elsevier Inc.

  20. The effects of grip width on sticking region in bench press.

    PubMed

    Gomo, Olav; Van Den Tillaar, Roland

    2016-01-01

    The aim of this study was to examine the occurrence of the sticking region by examining how three different grip widths affect the sticking region in powerlifters' bench press performance. It was hypothesised that the sticking region would occur at the same joint angle of the elbow and shoulder independent of grip width, indicating a poor mechanical region for vertical force production at these joint angles. Twelve male experienced powerlifters (age 27.7 ± 8.8 years, mass 91.9 ± 15.4 kg) were tested in one repetition maximum (1-RM) bench press with a narrow, medium and wide grip. Joint kinematics, timing, bar position and velocity were measured with a 3D motion capture system. All participants showed a clear sticking region with all three grip widths, but this sticking region was not found to occur at the same joint angles in all three grip widths, thereby rejecting the hypothesis that the sticking region would occur at the same joint angle of the elbow and shoulder independent of grip width. It is suggested that, due to the differences in moment arm of the barbell about the elbow joint in the sticking region, there still might be a poor mechanical region for total force production that is joint angle-specific.

  1. Vertical drying of a suspension of sticks: Monte Carlo simulation for continuous two-dimensional problem

    NASA Astrophysics Data System (ADS)

    Lebovka, Nikolai I.; Tarasevich, Yuri Yu.; Vygornitskii, Nikolai V.

    2018-02-01

    The vertical drying of a two-dimensional colloidal film containing zero-thickness sticks (lines) was studied by means of kinetic Monte Carlo (MC) simulations. The continuous two-dimensional problem for both the positions and orientations was considered. The initial state before drying was produced using a model of random sequential adsorption with isotropic orientations of the sticks. During the evaporation, an upper interface falls with a linear velocity in the vertical direction, and the sticks undergo translational and rotational Brownian motions. The MC simulations were run at different initial number concentrations (the numbers of sticks per unit area), pi, and solvent evaporation rates, u . For completely dried films, the spatial distributions of the sticks, the order parameters, and the electrical conductivities of the films in both the horizontal, x , and vertical, y , directions were examined. Significant evaporation-driven self-assembly and stratification of the sticks in the vertical direction was observed. The extent of stratification increased with increasing values of u . The anisotropy of the electrical conductivity of the film can be finely regulated by changes in the values of pi and u .

  2. When sticky fluids don't stick: yield-stress fluid drops on heated surfaces

    NASA Astrophysics Data System (ADS)

    Blackwell, Brendan; Wu, Alex; Ewoldt, Randy

    2016-11-01

    Yield-stress fluids, including gels and pastes, are effectively fluid at high stress and solid at low stress. In liquid-solid impacts, these fluids can stick and accumulate where they impact; this sticky behavior motivates several applications of these rheologically-complex materials. Here we describe experiments with aqueous yield stress fluids that are more 'sticky' than water at room temperature (e.g. supporting larger coating thicknesses), but are less 'sticky' at higher temperatures. Specifically, we study the conditions for aqueous yield stress fluids to bounce and slide on heated surfaces when water sticks. Here we present high-speed imaging and color interferometry to observe the thickness of the vapor layer between the drop and the surface during both stick and non-stick events. We use these data to gain insight into the physics behind the phenomenon of the yield-stress fluids bouncing and sliding, rather than sticking, on hot surfaces.

  3. Preslip and cascade processes initiating laboratory stick slip

    USGS Publications Warehouse

    McLaskey, Gregory C.; Lockner, David A.

    2014-01-01

    Recent modeling studies have explored whether earthquakes begin with a large aseismic nucleation process or initiate dynamically from the rapid growth of a smaller instability in a “cascade-up” process. To explore such a case in the laboratory, we study the initiation of dynamic rupture (stick slip) of a smooth saw-cut fault in a 76mm diameter cylindrical granite laboratory sample at 40–120MPa confining pressure. We use a high dynamic range recording system to directly compare the seismic waves radiated during the stick-slip event to those radiated from tiny (M _6) discrete seismic events, commonly known as acoustic emissions (AEs), that occur in the seconds prior to each large stick slip. The seismic moments, focal mechanisms, locations, and timing of the AEs all contribute to our understanding of their mechanics and provide us with information about the stick-slip nucleation process. In a sequence of 10 stick slips, the first few microseconds of the signals recorded from stick-slip instabilities are nearly indistinguishable from those of premonitory AEs. In this sense, it appears that each stick slip begins as an AE event that rapidly (~20 μs) grows about 2 orders of magnitude in linear dimension and ruptures the entire 150mm length of the simulated fault. We also measure accelerating fault slip in the final seconds before stick slip. We estimate that this slip is at least 98% aseismic and that it both weakens the fault and produces AEs that will eventually cascade-up to initiate the larger dynamic rupture.

  4. On justification of efficient Energy-Force parameters of Hydraulic-excavator main mechanisms

    NASA Astrophysics Data System (ADS)

    Komissarov, Anatoliy; Lagunova, Yuliya; Shestakov, Viktor; Lukashuk, Olga

    2018-03-01

    The article formulates requirements for energy-efficient designs of the operational equipment of a hydraulic excavator (its boom, stick and bucket) and defines, for a mechanism of that equipment, a new term “performance characteristic”. The drives of main rotation mechanisms of the equipment are realized by hydraulic actuators (hydraulic cylinders) and transmission (leverage) mechanisms, with the actuators (the cylinders themselves, their pistons and piston rods) also acting as links of the leverage. Those drives are characterized by the complexity of translating mechanical-energy parameters of the actuators into energy parameters of the driven links (a boom, a stick and a bucket). Relations between those parameters depend as much on the types of mechanical characteristics of the hydraulic actuators as on the types of structural schematics of the transmission mechanisms. To assess how energy-force parameters of the driven links change when a typical operation is performed, it was proposed to calculate performance characteristics of the main mechanisms as represented by a set of values of transfer functions, i.e. by functional dependences between driven links and driving links (actuators). Another term “ideal performance characteristic” of a mechanism was introduced. Based on operation-emulating models for the main mechanisms of hydraulic excavators, analytical expressions were derived to calculate kinematic and force transfer functions of the main mechanisms.

  5. Physics of the mechanical toy Gee-Haw Whammy Diddle.

    PubMed

    Marek, Martin; Badin, Matej; Plesch, Martin

    2018-02-27

    Gee-Haw Whammy Diddle is a seemingly simple mechanical toy consisting of a wooden stick and a second stick that is made up of a series of notches with a propeller at its end. When the wooden stick is pulled over the notches, the propeller starts to rotate. Despite its simplicity, physical principles governing the motion of the stick and the propeller are rather complicated and interesting. Here we provide a thorough analysis of the system and parameters influencing the motion. We show that contrary to the results published on this topic so far, neither elliptic motion of the stick nor frequency synchronization is needed for starting a stable motion of the propeller.

  6. The impact of wood ice cream sticks' origin on the aroma of exposed ice cream mixes.

    PubMed

    Jiamyangyuen, S; Delwiche, J F; Harper, W J

    2002-02-01

    The effect of volatile compounds in white birch sticks obtained from four different geographical locations on the aroma of ice cream mix was investigated. Sensory evaluation, (specifically, a series of warmed-up paired comparisons) was conducted on stick-exposed ice cream mixes to determine whether aroma differences in those mixes could be detected. Batches of ice cream mix were exposed to the sticks and aged for 6 d at 4 degrees C and then assessed by the panelists by pairwise comparison. Findings suggest that differences in aroma of mixes that have been exposed to white birch sticks from four different geographical origins can be distinguished perceptually.

  7. Effect of operation parameters on the slagging near swirl coal burner throat

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Changfu You; Yong Zhou

    2006-10-15

    Fluid flow, heat transfer, coal combustion, and slagging processes had been numerically simulated near a swirl burner throat. The effect of the ratio distribution of each burner air, their swirling numbers, and the coal character on the slagging process had been analyzed. The computation results indicate that the maximal sticking-particle numbers occur at the uppermost waterwall, while the sticking-particle number at neither waterwall near the swirl burner outlet is very small. The swirling number has a significant effect on the number of the sticking particle. The sticking-particle number increases rapidly with the increment of the outer secondary air and themore » primary air-swirling numbers, respectively, because it can strengthen the flow entrainment ability to carry more particles to the waterwall. The inner secondary air has a complicated influence on the slagging process. When the inner secondary air-swirling number is about middle intensive degree (about 0.9), the sticking-particle number reaches maximum. If the inner secondary air-swirling number continues increasing, then the coal particles will combust completely and reduce the particle concentration, thus decrease the sticking-particle number. The ratio of each air has a slight influence on the sticking-particle number relative to the swirling number. The coal particles with small mean diameter combust completely, which can reduce the sticking-particle number. 13 refs., 16 figs., 1 tab.« less

  8. Influence of Hydroxyapatite Stick on Pedicle Screw Fixation in Degenerative Lumbar Spine: Biomechanical and Radiologic Study.

    PubMed

    Shin, Sung Joon; Lee, Ji-Ho; Lee, Jae Hyup

    2017-07-01

    A prospective, within-patient, left-right comparative study. To evaluate the efficacy of hydroxyapatite (HA) stick augmentation method by comparing the insertional torque of the pedicle screw in osteoporotic and nonosteoporotic patients. Unsatisfactory clinical outcomes after spine surgery in osteoporotic patients are related to pedicle screw loosening or pull-outs. HA, as a bone graft extender, has a possibility to enhance the fixation strength at the bone-screw interface. From November 2009 to December 2010, among patients who required bilateral pedicle screw fixation for lumbar spine surgery, 22 patients were enrolled, who recieved unilateral HA stick augmentation and completed intraoperative insertional torque measurement of each pedicle screws. On the basis of preoperative evaluation of bone mineral density, patients with osteoporosis had 2 HA sticks inserted unilaterally, and 1 stick for patients without osteoporosis. Pedicle screw loosening and pull-outs were assessed using 12-month postoperative CT scans and follow-up radiographs. Clinical evaluation was done preoperatively and at 1 year postoperatively, based on Visual Analog Scale score, Oswestry Disability Index, and Short Form-36 Health Survey. Regardless of bone mineral density, the average torque value of all pedicle screws with HA stick insertion (HA stick inserted group) was significantly higher than that of all pedicle screws without HA insertion (control group) (P<0.0001). Same results were seen in the HA stick inserted subgroups and the control subgroups within both of the osteoporosis group (P=0.009) and the nonosteoporosis group (P=0.0004). There was no statistically significant difference of the rate of pedicle screw loosening in between the HA stick inserted group and the control group. Clinical evaluation also showed no statistically significant difference in between patients with loosening and those without. The enhancement of initial pedicle screw fixation strength in osteoporotic patients can be achieved by HA stick augmentation.

  9. Characterization of cosmetic sticks at Xiaohe Cemetery in early Bronze Age Xinjiang, China

    NASA Astrophysics Data System (ADS)

    Mai, Huijuan; Yang, Yimin; Abuduresule, Idelisi; Li, Wenying; Hu, Xingjun; Wang, Changsui

    2016-01-01

    Cosmetics have been studied for a long time in the society and culture research, and its consumption is regarded as a cultural symbol of human society. This paper focuses on the analysis of the red cosmetic sticks, found in Xiaohe Cemetery (1980-1450BC), Xinjiang, China. The structure of the red cosmetic sticks was disclosed by SR-μCT scanning (Synchrotron Radiation Micro-computed Tomography), while the chemical components were characterized by FTIR (Fourier Transform Infrared Spectroscopy), Raman Spectroscopy and Proteomics. The results suggested that the cosmetic sticks were made from the cattle heart and covered with a layer of hematite powders as the pigment. Given the numerous red painted relics in Xiaohe Cemetery, this kind of cosmetic sticks might be used as a primitive form of crayon for makeup and painting. The usage of cattle hearts as cosmetic sticks is firstly reported up to our knowledge, which not only reveals the varied utilizations of cattle in Xiaohe Cemetery but also shows the distinctive religious function. Furthermore, these red cosmetic sticks were usually buried with women, implying that the woman may be the painter and play a special role in religious activities.

  10. Stick balancing, falls and Dragon-Kings

    NASA Astrophysics Data System (ADS)

    Cabrera, J. L.; Milton, J. G.

    2012-05-01

    The extent to which the occurrence of falls, the dominant feature of human attempts to balance a stick at their fingertip, can be predicted is examined in the context of the "Dragon-King" hypothesis. For skilled stick balancers, fluctuations in the controlled variable, namely the vertical displacement angle θ, exhibit power law behaviors. When stick balancing is made less stable by either decreasing the length of the stick or by requiring the subject to balance the stick on the surface of a table tennis racket, systematic departures from the power law behaviors are observed in the range of large θ. This observation raises the possibility that the presence of departures from the power law in the large length scale region, possibly Dragon-Kings, may identify situations in which the occurrence of a fall is more imminent. However, whether or not Dragon-Kings are observed, there is a Weibull-type survival function for stick falling. The possibility that increased risk of falling can, at least to some extent, be predicted from fluctuations in the controlled variable before the event occurs has important implications for the development of preventative strategies for the management of phenomena ranging from earthquakes to epileptic seizures to falls in the elderly.

  11. Characterization of cosmetic sticks at Xiaohe Cemetery in early Bronze Age Xinjiang, China

    PubMed Central

    Mai, Huijuan; Yang, Yimin; Abuduresule, Idelisi; Li, Wenying; Hu, Xingjun; Wang, Changsui

    2016-01-01

    Cosmetics have been studied for a long time in the society and culture research, and its consumption is regarded as a cultural symbol of human society. This paper focuses on the analysis of the red cosmetic sticks, found in Xiaohe Cemetery (1980–1450BC), Xinjiang, China. The structure of the red cosmetic sticks was disclosed by SR-μCT scanning (Synchrotron Radiation Micro-computed Tomography), while the chemical components were characterized by FTIR (Fourier Transform Infrared Spectroscopy), Raman Spectroscopy and Proteomics. The results suggested that the cosmetic sticks were made from the cattle heart and covered with a layer of hematite powders as the pigment. Given the numerous red painted relics in Xiaohe Cemetery, this kind of cosmetic sticks might be used as a primitive form of crayon for makeup and painting. The usage of cattle hearts as cosmetic sticks is firstly reported up to our knowledge, which not only reveals the varied utilizations of cattle in Xiaohe Cemetery but also shows the distinctive religious function. Furthermore, these red cosmetic sticks were usually buried with women, implying that the woman may be the painter and play a special role in religious activities. PMID:26820435

  12. Characterization of cosmetic sticks at Xiaohe Cemetery in early Bronze Age Xinjiang, China.

    PubMed

    Mai, Huijuan; Yang, Yimin; Abuduresule, Idelisi; Li, Wenying; Hu, Xingjun; Wang, Changsui

    2016-01-28

    Cosmetics have been studied for a long time in the society and culture research, and its consumption is regarded as a cultural symbol of human society. This paper focuses on the analysis of the red cosmetic sticks, found in Xiaohe Cemetery (1980-1450BC), Xinjiang, China. The structure of the red cosmetic sticks was disclosed by SR-μCT scanning (Synchrotron Radiation Micro-computed Tomography), while the chemical components were characterized by FTIR (Fourier Transform Infrared Spectroscopy), Raman Spectroscopy and Proteomics. The results suggested that the cosmetic sticks were made from the cattle heart and covered with a layer of hematite powders as the pigment. Given the numerous red painted relics in Xiaohe Cemetery, this kind of cosmetic sticks might be used as a primitive form of crayon for makeup and painting. The usage of cattle hearts as cosmetic sticks is firstly reported up to our knowledge, which not only reveals the varied utilizations of cattle in Xiaohe Cemetery but also shows the distinctive religious function. Furthermore, these red cosmetic sticks were usually buried with women, implying that the woman may be the painter and play a special role in religious activities.

  13. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Clausing, R.E.

    Equations based on kinetic theory relate the contamination of refractory metals in vacuum to the appropriate variables. Several examples are given for which the allowable system pressures are calculated. The examples illustrate the effect of varying several parameters. The importance of the sticking factor for active gases on hot refractory metals and its effect on the system design are discussed. The data for estimating the sticking factor for O/sub 2/ on Nb are given, along with some estimated values. Experimental data on the composition and rates of outgassing of ultrahigh-vacuum systems and their importance in system design are discussed. Severalmore » methods of reducing contamination rates and the relative ease and effectiveness of these methods are presented. It was concluded that tests of 1000 hr or longer will probably require system pressures of between 10/sup -9/ and 10/sup -6/ torr, the particular pressure depending upon the residual gas composition, test duration, allowable contamination level, and the other variables discussed. Since the most important source of contamination in a properly designed ultrahigh-vacuum system is the outgassing process, bakeable systems should be designed to operate with walls as cool as practical, and to have a minimum of surface area and outgassing materials inside. Considerable added protection may be obtained by incorporating sacrificial getter surfaces in the system, or, alternatively, higher pressures may be tolerated if proper getter design is used. (auth)« less

  14. Incentivizing wellness in the workplace: sticks (not carrots) send stigmatizing signals.

    PubMed

    Tannenbaum, David; Valasek, Chad J; Knowles, Eric D; Ditto, Peter H

    2013-08-01

    Companies often provide incentives for employees to maintain healthy lifestyles. These incentives can take the form of either discounted premiums for healthy-weight employees ("carrot" policies) or increased premiums for overweight employees ("stick" policies). In the three studies reported here, we demonstrated that even when stick and carrot policies are formally equivalent, they do not necessarily convey the same information to employees. Stick but not carrot policies were viewed as reflecting negative company attitudes toward overweight employees (Study 1a) and were evaluated especially negatively by overweight participants (Study 1b). This was true even when overweight employees paid less money under the stick than under the carrot policy. When acting as policymakers (Study 2), participants with high levels of implicit overweight bias were especially likely to choose stick policies-often on the grounds that such policies were cost-effective-even when doing so was more costly to the company. Policymakers should realize that the framing of incentive programs can convey tacit, and sometimes stigmatizing, messages.

  15. Application of denaturing high-performance liquid chromatography (DHPLC) for the identification of fish: a new way to determine the composition of processed food containing multiple species.

    PubMed

    Le Fresne, Sophie; Popova, Milena; Le Vacon, Françoise; Carton, Thomas

    2011-12-14

    The identification of fish species in transformed food products is difficult because the existing methods are not adapted to heat-processed products containing more than one species. Using a common to all vertebrates region of the cytochrome b gene, we have developed a denaturing high-performance liquid chromatography (DHPLC) fingerprinting method, which allowed us to identify most of the species in commercial crab sticks. Whole fish and fillets were used for the creation of a library of referent DHPLC profiles. Crab sticks generated complex DHPLC profiles in which the number of contained fish species can be estimated by the number of major fluorescence peaks. The identity of some of the species was predicted by comparison of the peaks with the referent profiles, and others were identified after collection of the peak fractions, reamplification, and sequencing. DHPLC appears to be a quick and efficient method to analyze the species composition of complex heat-processed fish products.

  16. Streaming potential generated by a pressure-driven flow over a super-hydrophobic surface

    NASA Astrophysics Data System (ADS)

    Zhao, Hui

    2010-11-01

    The streaming potential generated by a pressured-driven flow over a weakly charged striped slip-stick surface (the zeta potential of the surface is smaller than the thermal potential (25 mV) with an arbitrary double layer thickness is theoretically studied by solving the Poisson-Boltzmann equation and Stokes equation. A series solution of the streaming potential is derived. Approximate expressions for the streaming potential in the limits of thin double layers and thick double layers are also presented, in excellent agreement with the full solution. The streaming potential is compared against that over a homogenously charged smooth surface. Our results indicate that the streaming potential over a super-hydrophobic surface only can be enhanced when the liquid-gas interface is charged. In addition, as the double layer thickness increases, the advantage of the super-hydrophobic surface diminishes. The impact of a slip-stick surface on the streaming potential might provide guidance for designing novel and efficient microfludic energy conversion devices using a super-hydrophobic surface.

  17. Moxa-stick suffumigation for disinfecting air in hematology and hematopoietic stem cell transplantation wards with class 100 laminar flow.

    PubMed

    He, Jing-song; Yang, Qing; Huang, Wei-jia; Hu, Xiao-rong

    2014-04-01

    To evaluate the effect of moxa-stick suffumigation in the hematology and hematopoietic stem cell transplantation (HSCT) wards with luminar flow. The plate exposure method was used to measure the effect of air-disinfection of moxa-stick suffumigation in hematology and HSCT wards. The yearly average qualified rates of air sampling in HSCT wards were evaluated from 2007 to 2010. To further investigate the disinfecting effect of moxa-stick suffumigation, the colony counts of common pathogens (including Staphylcoccus aureus and Pseudomonas aeruginosa) before and after moxa-stick suffumigation were compared. The mean air quality rates of the HSCT wards with class 100 laminar flow were all above 90.0% (91.2%-96.2%) from 2007 to 2010. Moxa-stick suffumigation effectively decreased the presence of bacteria in the hematology ward's air (P<0.01). The most notable effect was the drastic reduction in the colony counts of Staphylococcus aureus and Pseudomonas aeruginosa on the blood plates exposed to air treated with moxa-stick suffumigation (77.1±52.9 cfu/m(2) vs 196.1±87.5 cfu/m(2), P<0.01; and 100.2±35.3 cfu/m(2) vs 371.5±35.3 cfu/m(2), P<0.01). Moxa-stick suffumigation proved to be a reliable and effective airdisinfection method for hematology and HSCT wards, and hence, it should be employed extensively.

  18. A Comprehensive Study of Hydrogen Adsorbing to Amorphous Water ice: Defining Adsorption in Classical Molecular Dynamics

    NASA Astrophysics Data System (ADS)

    Dupuy, John L.; Lewis, Steven P.; Stancil, P. C.

    2016-11-01

    Gas-grain and gas-phase reactions dominate the formation of molecules in the interstellar medium (ISM). Gas-grain reactions require a substrate (e.g., a dust or ice grain) on which the reaction is able to occur. The formation of molecular hydrogen (H2) in the ISM is the prototypical example of a gas-grain reaction. In these reactions, an atom of hydrogen will strike a surface, stick to it, and diffuse across it. When it encounters another adsorbed hydrogen atom, the two can react to form molecular hydrogen and then be ejected from the surface by the energy released in the reaction. We perform in-depth classical molecular dynamics simulations of hydrogen atoms interacting with an amorphous water-ice surface. This study focuses on the first step in the formation process; the sticking of the hydrogen atom to the substrate. We find that careful attention must be paid in dealing with the ambiguities in defining a sticking event. The technical definition of a sticking event will affect the computed sticking probabilities and coefficients. Here, using our new definition of a sticking event, we report sticking probabilities and sticking coefficients for nine different incident kinetic energies of hydrogen atoms [5-400 K] across seven different temperatures of dust grains [10-70 K]. We find that probabilities and coefficients vary both as a function of grain temperature and incident kinetic energy over the range of 0.99-0.22.

  19. Improving Classroom Behavior: The Carrot and the Stick.

    ERIC Educational Resources Information Center

    Talent, Barbara K.; Busch, Suzanne G.

    A set of practical behavior change techniques for improving young children's classroom behavior are briefly discussed. Techniques are classified and discussed under two general categories: those that reduce frequency of behaviors ("sticks") and those that increase their frequency ("carrots"). Included under "sticks" are techniques such as ignoring…

  20. Dead Element Replicating: Degenerate R2 Element Replication and rDNA Genomic Turnover in the Bacillus rossius Stick Insect (Insecta: Phasmida)

    PubMed Central

    Martoni, Francesco; Eickbush, Danna G.; Scavariello, Claudia; Luchetti, Andrea; Mantovani, Barbara

    2015-01-01

    R2 is an extensively investigated non-LTR retrotransposon that specifically inserts into the 28S rRNA gene sequences of a wide range of metazoans, disrupting its functionality. During R2 integration, first strand synthesis can be incomplete so that 5’ end deleted copies are occasionally inserted. While active R2 copies repopulate the locus by retrotransposing, the non-functional truncated elements should frequently be eliminated by molecular drive processes leading to the concerted evolution of the rDNA array(s). Although, multiple R2 lineages have been discovered in the genome of many animals, the rDNA of the stick insect Bacillus rossius exhibits a peculiar situation: it harbors both a canonical, functional R2 element (R2Brfun) as well as a full-length but degenerate element (R2Brdeg). An intensive sequencing survey in the present study reveals that all truncated variants in stick insects are present in multiple copies suggesting they were duplicated by unequal recombination. Sequencing results also demonstrate that all R2Brdeg copies are full-length, i. e. they have no associated 5' end deletions, and functional assays indicate they have lost the active ribozyme necessary for R2 RNA maturation. Although it cannot be completely ruled out, it seems unlikely that the degenerate elements replicate via reverse transcription, exploiting the R2Brfun element enzymatic machinery, but rather via genomic amplification of inserted 28S by unequal recombination. That inactive copies (both R2Brdeg or 5'-truncated elements) are not eliminated in a short term in stick insects contrasts with findings for the Drosophila R2, suggesting a widely different management of rDNA loci and a lower efficiency of the molecular drive while achieving the concerted evolution. PMID:25799008

  1. High precise measurement of tiny angle dimensional holes for the unit-holes of the LAMOST Focal Plane Plate

    NASA Astrophysics Data System (ADS)

    Zhou, Zengxiang; Jin, Yi; Zhai, Chao; Xing, Xiaozheng

    2008-07-01

    In the LAMOST project, the unit-holes on the Focal Plane Plate are the final installation location of the optical fiber positioning system. Theirs precision will influence the observation efficiency of the LAMOST. For the unique requirements, the unit-holes on the Focal Plane Plate are composed by a series of tiny angle dimensional holes which dimensional angle are between 16' to 2.5°. According to these requirements, the measurement of the tiny angle dimensional holes for the unit-holes needs to less than 3'. And all the unit-holes point to the virtual sphere center of the Focal Plane Plate. To that end, the angle departure of the unit-holes axis is changed to the distance from the virtual sphere center of Focal Plane Plate to the unit-holes axis. That is the better way to evaluate the technical requirements of the dimensional angle errors. In the measuring process, common measuring methods do not fit for the tiny angle dimensional hole by CMM(coordinate measurement machine). An extraordinary way to solve this problem is to insert a measuring stick into a unit-hole, with a target ball on the stick. Then measure the low point of the ball center and pull out the stick for the high station of center. Finally, calculate the two points for the unit-hole axis to get the angle departure. But on the other hand, use this methods will bring extra errors for the measuring stick and the target ball. For better analysis this question, a series experiments are mentioned in this paper, which testify that the influence of the measure implement is little. With increasing the distance between the low point and the high point position in the measuring process should enhance the accuracy of dimensional angle measurement.

  2. Note: Versatile sample stick for neutron scattering experiments in high electric fields

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bartkowiak, M., E-mail: marek.bartkowiak@psi.ch; White, J. S.; Laboratory for Quantum Magnetism, Ecole Polytechnique Fédérale de Lausanne

    2014-02-15

    We present a versatile high voltage sample stick that fits into all cryomagnets and standard cryostats at the Swiss Spallation Neutron Source, Paul Scherrer Institut, and which provides a low effort route to neutron scattering experiments that combine electric field with low temperature and magnetic field. The stick allows for voltages up to 5 kV and can be easily adapted for different scattering geometries. We discuss the design consideration and thermal behavior of the stick, and give one example to showcase the abilities of the device.

  3. Methods and apparatus to produce stick-slip motion of logging tool attached to a wireline drawn upward by a continuously rotating wireline drum

    DOEpatents

    Vail, III, William Banning; Momii, Steven Thomas

    1998-01-01

    Methods and apparatus are described to produce stick-slip motion of a logging tool within a cased well attached to a wireline that is drawn upward by a continuously rotating wireline drum. The stick-slip motion results in the periodic upward movement of the tool in the cased well described in terms of a dwell time during which time the tool is stationary, the move time during which time the tool moves, and the stroke that is upward distance that the tool translates during the "slip" portion of the stick-slip motion. This method of measurement is used to log the well at different vertical positions of the tool. Therefore, any typical "station-to-station logging tool" may be modified to be a "continuous logging tool", where "continuous" means that the wireline drum continually rotates while the tool undergoes stick-slip motion downhole and measurements are performed during the dwell times when the tool is momentarily stationary. The stick-slip methods of operation and the related apparatus are particularly described in terms of making measurements of formation resistivity from within a cased well during the dwell times when the tool is momentarily stationary during the periodic stick-slip motion of the logging tool.

  4. Methods and apparatus to produce stick-slip motion of logging tool attached to a wireline drawn upward by a continuously rotating wireline drum

    DOEpatents

    Vail, W.B. III; Momii, S.T.

    1998-02-10

    Methods and apparatus are described to produce stick-slip motion of a logging tool within a cased well attached to a wireline that is drawn upward by a continuously rotating wireline drum. The stick-slip motion results in the periodic upward movement of the tool in the cased well described in terms of a dwell time during which time the tool is stationary, the move time during which time the tool moves, and the stroke that is upward distance that the tool translates during the ``slip`` portion of the stick-slip motion. This method of measurement is used to log the well at different vertical positions of the tool. Therefore, any typical ``station-to-station logging tool`` may be modified to be a ``continuous logging tool,`` where ``continuous`` means that the wireline drum continually rotates while the tool undergoes stick-slip motion downhole and measurements are performed during the dwell times when the tool is momentarily stationary. The stick-slip methods of operation and the related apparatus are particularly described in terms of making measurements of formation resistivity from within a cased well during the dwell times when the tool is momentarily stationary during the periodic stick-slip motion of the logging tool. 12 figs.

  5. Creep to inertia dominated stick-slip behavior in sliding friction modulated by tilted non-uniform loading

    NASA Astrophysics Data System (ADS)

    Tian, Pengyi; Tao, Dashuai; Yin, Wei; Zhang, Xiangjun; Meng, Yonggang; Tian, Yu

    2016-09-01

    Comprehension of stick-slip motion is very important for understanding tribological principles. The transition from creep-dominated to inertia-dominated stick-slip as the increase of sliding velocity has been described by researchers. However, the associated micro-contact behavior during this transition has not been fully disclosed yet. In this study, we investigated the stick-slip behaviors of two polymethyl methacrylate blocks actively modulated from the creep-dominated to inertia-dominated dynamics through a non-uniform loading along the interface by slightly tilting the angle of the two blocks. Increasing the tilt angle increases the critical transition velocity from creep-dominated to inertia-dominated stick-slip behaviors. Results from finite element simulation disclosed that a positive tilt angle led to a higher normal stress and a higher temperature on blocks at the opposite side of the crack initiating edge, which enhanced the creep of asperities during sliding friction. Acoustic emission (AE) during the stick-slip has also been measured, which is closely related to the different rupture modes regulated by the distribution of the ratio of shear to normal stress along the sliding interface. This study provided a more comprehensive understanding of the effect of tilted non-uniform loading on the local stress ratio, the local temperature, and the stick-slip behaviors.

  6. Membrane Distillation of Meat Industry Effluent with Hydrophilic Polyurethane Coated Polytetrafluoroethylene Membranes

    PubMed Central

    Mostafa, M. G.; Zhu, Bo; Cran, Marlene; Dow, Noel; Milne, Nicholas; Desai, Dilip

    2017-01-01

    Meat rendering operations produce stick water waste which is rich in proteins, fats, and minerals. Membrane distillation (MD) may further recover water and valuable solids, but hydrophobic membranes are contaminated by the fats. Here, commercial hydrophobic polytetrafluorethylene (PTFE) membranes with a hydrophilic polyurethane surface layer (PU-PTFE) are used for the first time for direct contact MD (DCMD) on real poultry, fish, and bovine stick waters. Metal membrane microfiltration (MMF) was also used to capture fats prior to MD. Although the standard hydrophobic PTFE membranes failed rapidly, PU-PTFE membranes effectively processed all stick water samples to colourless permeate with sodium rejections >99%. Initial clean solution fluxes 5–6 L/m2/h declined to less than half during short 40% water recovery tests for all stick water samples. Fish stick water uniquely showed reduced fouling and up to 78% water recovery. Lost flux was easily restored by rinsing the membrane with clean water. MMF prior to MD removed 92% of fats, facilitating superior MD performance. Differences in fouling between stick waters were attributed to temperature polarisation from higher melt temperature fats and relative proportions to proteins. Hydrophilic coated MD membranes are applicable to stick water processing but further studies should consider membrane cleaning and longer-term stability. PMID:28961203

  7. A novel tool for the prediction of tablet sticking during high speed compaction.

    PubMed

    Abdel-Hamid, Sameh; Betz, Gabriele

    2012-01-01

    During tableting, capping is a problem of cohesion while sticking is a problem of adhesion. Sticking is a multi-composite problem; causes are either material or machine related. Nowadays, detecting such a problem is a pre-requisite in the early stages of development. The aim of our study was to investigate sticking by radial die-wall pressure monitoring guided by compaction simulation. This was done by using the highly sticking drug; Mefenamic acid (MA) at different drug loadings with different fillers compacted at different pressures and speeds. By increasing MA loading, we found that viscoelastic fillers showed high residual radial pressure after compaction while plastic/brittle fillers showed high radial pressure during compaction, p < 0.05. Visually, plastic/brittle fillers showed greater tendencies for adhesion to punches than viscoelastic fillers while the later showed higher tendencies for adhesion to the die-wall. This was confirmed by higher values of axial stress transmission for plastic/brittle than viscoelastic fillers (higher punch surface/powder interaction), and higher residual die-wall and ejection forces for viscoelastic than plastic/brittle fillers, p < 0.05. Take-off force was not a useful tool to estimate sticking due to cohesive failure of the compacts. Radial die-wall pressure monitoring is suggested as a robust tool to predict sticking.

  8. Creep to inertia dominated stick-slip behavior in sliding friction modulated by tilted non-uniform loading.

    PubMed

    Tian, Pengyi; Tao, Dashuai; Yin, Wei; Zhang, Xiangjun; Meng, Yonggang; Tian, Yu

    2016-09-19

    Comprehension of stick-slip motion is very important for understanding tribological principles. The transition from creep-dominated to inertia-dominated stick-slip as the increase of sliding velocity has been described by researchers. However, the associated micro-contact behavior during this transition has not been fully disclosed yet. In this study, we investigated the stick-slip behaviors of two polymethyl methacrylate blocks actively modulated from the creep-dominated to inertia-dominated dynamics through a non-uniform loading along the interface by slightly tilting the angle of the two blocks. Increasing the tilt angle increases the critical transition velocity from creep-dominated to inertia-dominated stick-slip behaviors. Results from finite element simulation disclosed that a positive tilt angle led to a higher normal stress and a higher temperature on blocks at the opposite side of the crack initiating edge, which enhanced the creep of asperities during sliding friction. Acoustic emission (AE) during the stick-slip has also been measured, which is closely related to the different rupture modes regulated by the distribution of the ratio of shear to normal stress along the sliding interface. This study provided a more comprehensive understanding of the effect of tilted non-uniform loading on the local stress ratio, the local temperature, and the stick-slip behaviors.

  9. Creep to inertia dominated stick-slip behavior in sliding friction modulated by tilted non-uniform loading

    PubMed Central

    Tian, Pengyi; Tao, Dashuai; Yin, Wei; Zhang, Xiangjun; Meng, Yonggang; Tian, Yu

    2016-01-01

    Comprehension of stick-slip motion is very important for understanding tribological principles. The transition from creep-dominated to inertia-dominated stick-slip as the increase of sliding velocity has been described by researchers. However, the associated micro-contact behavior during this transition has not been fully disclosed yet. In this study, we investigated the stick-slip behaviors of two polymethyl methacrylate blocks actively modulated from the creep-dominated to inertia-dominated dynamics through a non-uniform loading along the interface by slightly tilting the angle of the two blocks. Increasing the tilt angle increases the critical transition velocity from creep-dominated to inertia-dominated stick-slip behaviors. Results from finite element simulation disclosed that a positive tilt angle led to a higher normal stress and a higher temperature on blocks at the opposite side of the crack initiating edge, which enhanced the creep of asperities during sliding friction. Acoustic emission (AE) during the stick-slip has also been measured, which is closely related to the different rupture modes regulated by the distribution of the ratio of shear to normal stress along the sliding interface. This study provided a more comprehensive understanding of the effect of tilted non-uniform loading on the local stress ratio, the local temperature, and the stick-slip behaviors. PMID:27641908

  10. The Sticking Point in the Bench Press, the Squat, and the Deadlift: Similarities and Differences, and Their Significance for Research and Practice.

    PubMed

    Kompf, Justin; Arandjelović, Ognjen

    2017-04-01

    Since it was first observed, and especially so in recent years, the phenomenon of the so-called "sticking point" in resistance training has attracted a substantial amount of sports and exercise science research. Broadly speaking, the sticking point is understood as the position in the range of motion of a lift at which a disproportionately large increase in the difficulty associated with continuing the lift is experienced. Hence the sticking point is inherently the performance bottleneck, and is also associated with an increased chance of exercise form deterioration or breakdown. Understanding the aspects of lifting performance which should be analysed in order to pinpoint the cause of a specific sticking point and therefore devise an effective training strategy to overcome it is of pervasive importance to strength practitioners, and is conducive to injury avoidance and continued progress. In this paper, we survey a range of physiological and biomechanical mechanisms which contribute to the development of sticking points, and then, led by this insight, review and analyse the findings of the existing observational research on the occurrence of sticking points in three ubiquitous exercises: the bench press, the squat, and the deadlift. The findings of our analysis should be used to inform future research and current resistance training practice.

  11. Radiative corrections to quantum sticking on graphene

    NASA Astrophysics Data System (ADS)

    Sengupta, Sanghita; Clougherty, Dennis P.

    2017-07-01

    We study the sticking rate of atomic hydrogen to suspended graphene using four different methods that include contributions from processes with multiphonon emission. We compare the numerical results of the sticking rate obtained by: (i) the loop expansion of the atom self-energy; (ii) the noncrossing approximation (NCA); (iii) the independent boson model approximation (IBMA); and (iv) a leading-order soft-phonon resummation method (SPR). The loop expansion reveals an infrared problem, analogous to the infamous infrared problem in QED. The two-loop contribution to the sticking rate gives a result that tends to diverge for large membranes. The latter three methods remedy this infrared problem and give results that are finite in the limit of an infinite membrane. We find that for micromembranes (sizes ranging 100 nm to 10 μ m ), the latter three methods give results that are in good agreement with each other and yield sticking rates that are mildly suppressed relative to the lowest-order golden rule rate. Lastly, we find that the SPR sticking rate decreases slowly to zero with increasing membrane size, while both the NCA and IBMA rates tend to a nonzero constant in this limit. Thus, approximations to the sticking rate can be sensitive to the effects of soft-phonon emission for large membranes.

  12. Influence of sticking vs non-sticking limits of moment of inertia and higher order deformations in the decay of 214,216Rn* compound systems

    NASA Astrophysics Data System (ADS)

    Mittal, Rajni; Jain, Deepika; Sharma, Manoj K.

    2017-12-01

    The dynamical cluster decay model (DCM) is employed to explore the relative effect of sticking (IS) and non-sticking (INS) limits of moment of inertia (MOI) in the decay of hot and rotating 214,216Rn* compound nuclei, formed in 16,18O + 198Pt reactions. Beside this, the nuclear deformation effects i.e. quadrupole β2 (static and dynamic) and higher order static deformations up to hexadecapole (β4) are duly incorporated and studied within DCM. The influence of both 'INS/IS' addressing rotational energy component and 'deformations' is gauged through the barrier characteristics, preformation factor and barrier lowering effects. The experimentally given ER and ff data is addressed by optimizing the neck-length ΔR, that strongly depends on the limiting angular momentum, which in turn depends on the sticking or non-sticking limits of interaction. In addition to this, the influence of increase in energy and neutron number is probed in reference to ER survival probability of Rn compound nucleus. Finally, the ff cross-sections of 214,216Rn* nuclei are predicted within sticking limit of moment of inertia as the same seems to be more suitable for such decay paths.

  13. Effects of skin-to-skin contact on autonomic pain responses in preterm infants.

    PubMed

    Cong, Xiaomei; Cusson, Regina M; Walsh, Stephen; Hussain, Naveed; Ludington-Hoe, Susan M; Zhang, Di

    2012-07-01

    The purpose of this randomized crossover trial was to determine the effects on autonomic responses in preterm infants of longer Kangaroo Care (30 minutes, KC30) and shorter KC (15 minutes, KC15) before and throughout heel stick compared with incubator care (IC). Beat-to-beat heart rate (HR) and spectral power analysis of heart rate variability, low frequency power (LF), high frequency power (HF), and LF/HF ratio were measured in 26 infants. HR changes from Baseline to Heel Stick were significantly less in KC30 and KC15 than in IC, and more infants had HR decrease in IC than in 2 KC conditions. In IC, LF and HF significantly increased from Baseline to Heel Stick and dropped from Heel Stick to Recovery; in 2 KC conditions, no changes across study phases were found. During Heel Stick, LF and HF were significantly higher in IC than in KC30. In all 3 conditions, LF/HF ratio decreased from Baseline to Heel Stick and increased to Recovery; no differences were found between IC and two KC conditions. Both longer and shorter KC before and throughout heel stick can stabilize HR response in preterm infants, and longer KC significantly affected infants' sympathetic and parasympathetic responses during heel stick compared with incubator care. This study showed that KC has a significant effect on reducing autonomic pain responses in preterm infants. The findings support that KC is a safe and effective pain intervention in the neonatal intensive care unit. Copyright © 2012 American Pain Society. Published by Elsevier Inc. All rights reserved.

  14. Prior leg massage decreases pain responses to heel stick in preterm babies.

    PubMed

    Jain, Sunil; Kumar, Praveen; McMillan, Douglas D

    2006-09-01

    Leg massage could inhibit the transmission of pain by 'closing the gate' or by activating the endogenous opioid pathway to decrease nociceptive transmission of pain associated with heel stick. The aim of this study is to determine the effects of massage therapy prior to heel stick on responses assessed by the Neonatal Infant Pain Scale (NIPS) (primary outcome), heart rate, respiratory rate and oxygen saturation (secondary outcomes) in infants who required a heel stick for blood sampling. This randomised, double-blind, crossover trial with infants from 1 to 7 days post birth excluded those with prior surgery, septicaemia, current assisted ventilation or an analgesic within 48 h. After informed consent, 13 infants received a 2-min massage of the ipsilateral leg prior to heel stick on the first study sampling and no massage on the next sampling 2-7 days later and 10 infants had the reverse order. The bedside nurse, blinded to the intervention, measured NIPS, heart rate, respiratory rate, and oxygen saturation prior to massage, after massage, and 5 min after heel stick. Serum cortisol was measured with the blood sampling. In 23 infants (birthweight 795-2507 g), there were no adverse physiologic effects of massage. After heel stick, NIPS (P < 0.001) and heart rate (P = 0.03) were increased in the no-massage group compared with the massage group. Respiratory rate, oxygen saturation and serum cortisol were not significantly different. Gentle massage of the leg prior to heel stick is safe and decreases pain responses in preterm infants.

  15. Glow Sticks: Spectra and Color Mixing

    ERIC Educational Resources Information Center

    Birriel, Jennifer; Birriel, Ignacio

    2014-01-01

    Glow sticks are a popular Halloween staple familiar to most of our students. The production of light via a chemical reaction is called "chemiluminescence," and glow sticks are often used as demonstrations and experiments in the chemistry classroom to study reaction rates as a function of temperature. A black light can be used to…

  16. A fundamental approach to the sticking of insect residues to aircraft wings

    NASA Technical Reports Server (NTRS)

    Yi, O.; Eiss, N. S.; Wightman, J. P.

    1988-01-01

    The aircraft industry is concerned with the increase of drag on planes due to the sticking of insects on critical airfoil areas. The objectives of the present study were to investigate the effects of surface energy and elasticity on the number of insects sticking onto the polymer coatings on a modified aircraft wing and to determine the mechanism by which insects stick onto surfaces during high velocity impact. Analyses including scanning electron microscopy, electron spectroscopy for chemical analysis and contact angle measurements of uncoated and polymer coated aluminum surfaces were performed. A direct relation between the number of insects sticking on a sample and its surface energy was obtained. Since the sticky liquid from a burst open insect will not spread on the low energy surface, it will ball up providing poor adhesion between the insect debris and the surface. The incoming air flow can easily blow off the insect debris and thus reducing the number of insects that remain stuck on the surface. Also a direct relation between the number of insect sticking onto a surface and their modulus of elasticity was obtained.

  17. Development of flow-through and dip-stick immunoassays for screening of sulfonamide residues.

    PubMed

    Zhang, Hongyan; Zhang, Yan; Wang, Shuo

    2008-08-20

    Two formats of membrane-based competitive enzyme immunoassays (flow-through and dip-stick) have been developed for the screening of sulfonamide residues in pig muscle and milk. Membrane was coated with anti-sulfonamide antibody and a sulfonamide hapten D2-horseradish peroxidase (HRP) conjugant was used as the labeled antigen for competitive assay of sulfonamides. Visual detection limits of the flow-through or dip-stick assay were 1-5 microg L(-1) or 1-10 microg L(-1) in buffer for seven sulfonamides, respectively. Assay validation was performed using samples spiked with single sulfonamide, spiked samples were tested using the developed strip assays and results were compared with those obtained by a validated high-performance liquid chromatograph (HPLC) method. Results showed that the two strip assays were correlated well with HPLC, respectively. With assay times of 5 min (flow-through) and 15 min (dip-stick), these rapid tests could offer simple, rapid and cost-effective on-site screening tools to detect sulfonamides in pig muscle (flow-through or dip-stick) or milk (only dip-stick).

  18. What do bonobos (Pan paniscus) understand about physical contact?

    PubMed

    Helme, Anne E; Call, Josep; Clayton, Nicola S; Emery, Nathan J

    2006-08-01

    The present study aimed to test what bonobos (Pan paniscus) understand about contact. The task consisted of a clear horizontal tube containing a piece of food and a stick with a disk attached. The bonobos chose which side to push or pull the stick for the disk to contact the food and make it accessible. There were 9 variations in tube design, which differed in the positions of the stick, disk, and food. All 5 bonobos passed at least 1 configuration. A recent study (A. E. Helme, N. S. Clayton, & N. J. Emery, 2006) found that rooks could learn only tube configurations that provided an asymmetrical stick cue, whereas bonobos did not demonstrate an understanding of contact but showed more individual variation, attending to the positions of the food, disk, and stick. ((c) 2006 APA, all rights reserved).

  19. Finding the Fertile Phase: Low-Cost Luteinizing Hormone Sticks Versus Electronic Fertility Monitor.

    PubMed

    Barron, Mary Lee; Vanderkolk, Kaitlin; Raviele, Kathleen

    To investigate if generic Wondfo ovulation sticks (WLH) are sufficiently sensitive to the luteinizing hormone (LH) surge in urine when used with the Marquette Fertility Algorithm. The electronic hormonal fertility monitor (EHFM) is highly accurate in detecting the LH surge but cost of the monitor and the accompanying test sticks has increased over the last several years. The EHFM is sensitive to detect the LH surge at 20 milli-international units per milliliter (mIU/mL); the WLH sticks are slightly less sensitive at 25 mIU/mL. A convenience sample of women using the Marquette Method of Natural Family Planning with the EHFM to avoid pregnancy were recruited (N = 54). Each participant used the EHFM every morning after cycle day 6 and tested morning and evening urine with the WLH stick until the day following detection of the LH surge on the EHFM. Forty-two women provided 219 cycles. Frequency of LH surge detection was 182/219 (83.1%) for EHFM and 203/219 (92.7%) for WLH sticks. Agreement between the EHFM and the WLH on the day of the LH surge was 97.7%. High fertility readings providing a warning of peak fertility at least 5 days before peak was 67% for the WLH; the EHFM was 47.7%. Paired sample correlations for high fertility was .174 (p = .014) and paired sample differences t was -4.729 (p = .000). The WLH stick is sufficiently sensitive to use in place of the EFHM for determining peak fertility and with the Marquette Fertility algorithm. Even with minimal use, WLH sticks cost about half the price of the monitor strips and provide more flexibility of use. Cost differences increase with the number of sticks used per cycle. Further research with a larger sample is needed to verify results.

  20. Self-spreading of the wetting ridge during stick-slip on a viscoelastic surface

    DOE PAGES

    Park, S. J.; Bostwick, J. B.; De Andrade, V.; ...

    2017-10-23

    Dynamic wetting behaviors on soft solids are important to interpret complex biological processes from cell–substrate interactions. Despite intensive research studies over the past half-century, the underlying mechanisms of spreading behaviors are not clearly understood. The most interesting feature of wetting on soft matter is the formation of a “wetting ridge”, a surface deformation by a competition between elasticity and capillarity. Dynamics of the wetting ridge formed at the three-phase contact line underlies the dynamic wetting behaviors, but remains largely unexplored mostly due to limitations in indirect observation. Here, we directly visualize wetting ridge dynamics during continuous- and stick-slip motions onmore » a viscoelastic surface using X-ray microscopy. Strikingly, we discover that the ridge spreads spontaneously during stick and triggers contact line depinning (stick-to-slip transition) by changing the ridge geometry which weakens the contact line pinning. Finally, we clarify ‘viscoelastic-braking’, ‘stick-slipping’, and ‘stick-breaking’ spreading behaviors through the ridge dynamics. In stick-breaking, no ridge-spreading occurs and contact line pinning (hysteresis) is enhanced by cusp-bending while preserving a microscopic equilibrium at the ridge tip. We have furthered the understanding of spreading behaviors on soft solids and demonstrated the value of X-ray microscopy in elucidating various dynamic wetting behaviors on soft solids as well as puzzling biological issues.« less

  1. You Must Keep Money Moving

    ERIC Educational Resources Information Center

    Heck, Andre; Vonk, Ron

    2009-01-01

    Physics teachers often like to discuss physics concepts with their students on the basis of simple demonstration experiments. In this article, we discuss an experiment for which one only needs a few coins of the same denomination and a wooden stick: the coins are laid alongside the stick on a horizontal surface, the stick is rotated about one of…

  2. LIBRE Stick Figure Tool: A Graphic Organizer to Foster Self-Regulated Social Cognitive Problem Solving

    ERIC Educational Resources Information Center

    Guerra, Norma S.

    2009-01-01

    Graphic organizers are powerful visual tools. The representation provides dimension and relationship to ideas and a framework for organization and elaboration. The LIBRE Stick Figure Tool is a graphic organizer for the problem-solving application of the LIBRE Model counseling approach. It resembles a "stick person" and offers the teacher and…

  3. D'Nealian Handwriting versus Circle-Stick Print.

    ERIC Educational Resources Information Center

    Thurber, Donald N.

    This paper argues against teaching children to make letters using circle-stick writing. It contends that the circle-stick method requires continued pen/pencil lifts hindering rhythm or flow in the writing process and that there is little carry-over value into cursive writing as the two scripts are totally different. D'Nealian print, one type of…

  4. Ball-Stick-Bird: Teaching with the Story Engram.

    ERIC Educational Resources Information Center

    Fuller, Renee

    1990-01-01

    This paper describes the Ball-Stick-Bird reading system, which shows students how all the letters of the alphabet can be built with three basic forms: a circle (ball), a line (stick), and an angle (bird). The method also uses modified phonics and developmental linguistics, aids story reading by using capital letters in the beginning, and enhances…

  5. Slow Earthquakes and The Mechanics of Slow Frictional Stick-Slip

    NASA Astrophysics Data System (ADS)

    Marone, Chris; Scuderi, Marco; Leeman, John; Saffer, Demian; Collettini, Cristiano; Johnson, Paul

    2015-04-01

    Slow earthquakes represent one mode of the spectrum of fault slip behaviors ranging from steady aseismic slip to normal earthquakes. Like normal earthquakes, slow earthquakes can occur repetitively, such that a fault fails in a form of stick-slip failure defined by interseismic strain accumulation and slow, quasidynamic slip. The mechanics of frictional stick-slip and seismogenic faulting appear to apply to slow earthquakes, however, the mechanisms that limit dynamic slip velocity, rupture propagation speed, and the scaling between moment and duration of slow earthquakes are poorly understood. Here, we describe laboratory experiments that explore the mechanics of repetitive, slow frictional stick-slip failure. We document the role of loading stiffness and friction constitutive behavior in dictating the properties of repetitive, frictional stick-slip. Our results show that a spectrum of dynamic and quasidynamic slip velocities can occur in stick-slip events depending on the relation between loading stiffness k and the rheologic critical stiffness kc given, in the context of rate and state friction, by the ratio of the friction rate parameter (b-a) divided by the critical friction distance Dc. Slow slip is favored by conditions for which k is ~ equal to kc, whereas normal, fast stick slip occurs when k/kc < 1. We explore the role of elastic coupling and spatially extended slip propagation by comparing slow slip results for shear in a layer driven by forcing blocks of varying stiffness. We evaluate our data in the framework of rate and state friction laws and focus on the frictional mechanics of slow stick-slip failure with special attention paid to the connections between quasidynamic failure and mechanisms of the brittle-ductile transition in fault rocks.

  6. Head-controlled assistive telerobot with extended physiological proprioception capability

    NASA Astrophysics Data System (ADS)

    Salganicoff, Marcos; Rahman, Tariq; Mahoney, Ricardo; Pino, D.; Jayachandran, Vijay; Kumar, Vijay; Chen, Shoupu; Harwin, William S.

    1995-12-01

    People with disabilities such as quadriplegia can use mouth-sticks and head-sticks as extension devices to perform desired manipulations. These extensions provide extended proprioception which allows users to directly feel forces and other perceptual cues such as texture present at the tip of the mouth-stick. Such devices are effective for two principle reasons: because of their close contact with the user's tactile and proprioceptive sensing abilities; and because they tend to be lightweight and very stiff, and can thus convey tactile and kinesthetic information with high-bandwidth. Unfortunately, traditional mouth-sticks and head-sticks are limited in workspace and in the mechanical power that can be transferred because of user mobility and strength limitations. We describe an alternative implementation of the head-stick device using the idea of a virtual head-stick: a head-controlled bilateral force-reflecting telerobot. In this system the end-effector of the slave robot moves as if it were at the tip of an imaginary extension of the user's head. The design goal is for the system is to have the same intuitive operation and extended proprioception as a regular mouth-stick effector but with augmentation of workspace volume and mechanical power. The input is through a specially modified six DOF master robot (a PerForceTM hand-controller) whose joints can be back-driven to apply forces at the user's head. The manipulation tasks in the environment are performed by a six degree-of-freedom slave robot (the Zebra-ZEROTM) with a built-in force sensor. We describe the prototype hardware/software implementation of the system, control system design, safety/disability issues, and initial evaluation tasks.

  7. The knight stick trap and knight stick sticky wraps: new tools for stable fly (Diptera: Muscidae) management

    USDA-ARS?s Scientific Manuscript database

    The stable fly is a noxious hematophagous pest of livestock, feral animals and humans. In the US, traps have been used for many years to survey stable flies and affect some degree of population reduction. A new stable fly trap, the Knight Stick (KS), has recently appeared on the market and studies w...

  8. Forest research notes, Pacific Northwest Forest Experiment Station, No. 30, June 21, 1940.

    Treesearch

    Donald N. Matthews; William G. Morris

    1940-01-01

    (Matthews)The test was made to determine the effect of three possible variations in the indicator sticks: 1. Variations in shape. Will square, round, or flat sticks of the same cross section, length, and exposure have the same moisture content? 2. Variation in exposure. Determine the effect of exposing the sticks in the open versus...

  9. Effect of hinge-moment parameters on elevator stick forces in rapid maneuvers

    NASA Technical Reports Server (NTRS)

    Jones, R. T.; Greenberg, H.

    1976-01-01

    The importance of the stick force per unit normal acceleration as a criterion of longitudinal stability and the critical dependence of this gradient on elevator hinge moment parameters are investigated with special reference to transient effects for maneuvers of short duration. The analysis shows that different combinations of elevator parameters, which give the same stick force per unit acceleration in turns, give widely different force variations during the entries into and recoveries from steady turns and during maneuvers of short duration such as abrupt pull-ups. The stick force per unit acceleration is greater for abrupt than for gradual control movements.

  10. Molecular basis of crystal morphology-dependent adhesion behavior of mefenamic acid during tableting.

    PubMed

    Waknis, Vrushali; Chu, Elza; Schlam, Roxana; Sidorenko, Alexander; Badawy, Sherif; Yin, Shawn; Narang, Ajit S

    2014-01-01

    The molecular basis of crystal surface adhesion leading to sticking was investigated by exploring the correlation of crystal adhesion to oxidized iron coated atomic force microscope (AFM) tips and bulk powder sticking behavior during tableting of two morphologically different crystals of a model drug, mefenamic acid (MA), to differences in their surface functional group orientation and energy. MA was recrystallized into two morphologies (plates and needles) of the same crystalline form. Crystal adhesion to oxidized iron coated AFM tips and bulk powder sticking to tablet punches was assessed using a direct compression formulation. Surface functional group orientation and energies on crystal faces were modeled using Accelrys Material Studio software. Needle-shaped morphology showed higher sticking tendency than plates despite similar particle size. This correlated with higher crystal surface adhesion of needle-shaped morphology to oxidized iron coated AFM probe tips, and greater surface energy and exposure of polar functional groups. Higher surface exposure of polar functional groups correlates with higher tendency to stick to metal surfaces and AFM tips, indicating involvement of specific polar interactions in the adhesion behavior. In addition, an AFM method is identified to prospectively assess the risk of sticking during the early stages of drug development.

  11. Comparison of sticking probabilities of metal atoms in magnetron sputtering deposition of CuZnSnS films

    NASA Astrophysics Data System (ADS)

    Sasaki, K.; Kikuchi, S.

    2014-10-01

    In this work, we compared the sticking probabilities of Cu, Zn, and Sn atoms in magnetron sputtering deposition of CZTS films. The evaluations of the sticking probabilities were based on the temporal decays of the Cu, Zn, and Sn densities in the afterglow, which were measured by laser-induced fluorescence spectroscopy. Linear relationships were found between the discharge pressure and the lifetimes of the atom densities. According to Chantry, the sticking probability is evaluated from the extrapolated lifetime at the zero pressure, which is given by 2l0 (2 - α) / (v α) with α, l0, and v being the sticking probability, the ratio between the volume and the surface area of the chamber, and the mean velocity, respectively. The ratio of the extrapolated lifetimes observed experimentally was τCu :τSn :τZn = 1 : 1 . 3 : 1 . This ratio coincides well with the ratio of the reciprocals of their mean velocities (1 /vCu : 1 /vSn : 1 /vZn = 1 . 00 : 1 . 37 : 1 . 01). Therefore, the present experimental result suggests that the sticking probabilities of Cu, Sn, and Zn are roughly the same.

  12. Intermittent stick-slip dynamics during the peeling of an adhesive tape from a roller.

    PubMed

    Cortet, Pierre-Philippe; Dalbe, Marie-Julie; Guerra, Claudia; Cohen, Caroline; Ciccotti, Matteo; Santucci, Stéphane; Vanel, Loïc

    2013-02-01

    We study experimentally the fracture dynamics during the peeling at a constant velocity of a roller adhesive tape mounted on a freely rotating pulley. Thanks to a high speed camera, we measure, in an intermediate range of peeling velocities, high frequency oscillations between phases of slow and rapid propagation of the peeling fracture. This so-called stick-slip regime is well known as the consequence of a decreasing fracture energy of the adhesive in a certain range of peeling velocity coupled to the elasticity of the peeled tape. Simultaneously with stick slip, we observe low frequency oscillations of the adhesive roller angular velocity which are the consequence of a pendular instability of the roller submitted to the peeling force. The stick-slip dynamics is shown to become intermittent due to these slow pendular oscillations which produce a quasistatic oscillation of the peeling angle while keeping constant the peeling fracture velocity (averaged over each stick-slip cycle). The observed correlation between the mean peeling angle and the stick-slip amplitude questions the validity of the usually admitted independence with the peeling angle of the fracture energy of adhesives.

  13. Resource allocation in neural networks for motor control

    NASA Astrophysics Data System (ADS)

    Milton, J.; Cummins, J.; Gunnoe, J.; Tollefson, M.; Cabrera, J. L.; Ohira, T.

    2006-03-01

    Multiplicative noise plays an important part of a non-predictive control mechanism for stick balancing at the fingertip. However, intentionally-directed movements are also used in stick balancing, particularly by beginners. The interplay between intentional and non-predictive control mechanisms for stick balancing was assessed using two dual task paradigms: the subject was asked to either move one of their legs rhythmically or to imagine moving their leg while balancing a stick (55.4 cm, 35 g) at their fingertip. Performance was measured by determining the stick survival function, i.e. the fraction of trials (total >=25) for which the stick remained balanced at time t as a function of t. Performance was increased by concurrent rhythmic leg movements (50% survival time shifted from 8-9s to 15s in a typical subject). Imagined movements resulted in a similar improvement (50% survival time of 20s for the above subject) suggesting that this enhancement is not simply related to mechanical vibrations of the fingertip induced by leg movement. These observations emphasize the importance of the development of mathematical models for neural control of skilled motor movements that take into resource allocation of limited resources, such as intention.

  14. What limits tool use in nonhuman primates? Insights from tufted capuchin monkeys (Sapajus spp.) and chimpanzees (Pan troglodytes) aligning three-dimensional objects to a surface

    PubMed Central

    la Cour, L. T.; Stone, B. W.; Hopkins, W.; Menzel, C.; Fragaszy, D.

    2013-01-01

    Perceptuomotor functions that support using hand tools can be examined in other manipulation tasks, such as alignment of objects to surfaces. We examined tufted capuchin monkeys’ and chimpanzees’ performance at aligning objects to surfaces while managing one or two spatial relations to do so. We presented 6 subjects of each species with a single stick to place into a groove, two sticks of equal length to place into two grooves, or two sticks joined as a T to place into a T-shaped groove. Tufted capuchins and chimpanzees performed equivalently on these tasks, aligning the straight stick to within 22.5° of parallel to the groove in approximately half of their attempts to place it, and taking more attempts to place the T stick than two straight sticks. The findings provide strong evidence that tufted capuchins and chimpanzees do not reliably align even one prominent axial feature of an object to a surface, and that managing two concurrent allocentric spatial relations in an alignment problem is significantly more challenging to them than managing two sequential relations. In contrast, humans from two years of age display very different perceptuomotor abilities in a similar task: they align sticks to a groove reliably on each attempt, and they readily manage two allocentric spatial relations concurrently. Limitations in aligning objects and in managing two or more relations at a time significantly constrain how nonhuman primates can use hand tools. PMID:23820935

  15. Evaluation of rheological, bioactives and baking characteristics of mango ginger (curcuma amada) enriched soup sticks.

    PubMed

    Crassina, K; Sudha, M L

    2015-09-01

    Wheat flour was replaced with mango ginger powder (MGP) at 0, 5, 10 and 15 %. Influence of MGP on rheological and baking characteristics was studied. Farinograph was used to study the mixing profile of wheat flour-MGP blend. Pasting profile of the blends namely gelatinization and retrogradation were carried out using micro-visco-amylograph. Test baking was done to obtain the optimum level of replacement and processing conditions. Sensory attributes consisting texture, taste, overall quality and breaking strength were assessed. Nutritional characterization of the soup sticks in terms of protein and starch in vitro digestibility, dietary fiber, minerals, polyphenols and antioxidant activity were determined using standard methods. With the increasing levels of MGP from 0 to 15 %, the farinograph water absorption increased from 60 to 66.7 %. A marginal increase in the gelatinization temperature from 65.4 to 66.2 °C was observed. Retrogradation of gelatinized starch granules decreased with the addition of MGP. The results indicated that the soup stick with 10 % MG had acceptable sensory attributes. The soup stick showed further improvement in terms of texture and breaking strength with the addition of gluten powder, potassium bromate and glycerol monostearate. The total dietary fiber and antioxidant activity of the soup sticks having 10 % MGP increased from 3.31 to 8.64 % and 26.83 to 48.06 % respectively as compared to the control soup sticks. MGP in soup sticks improved the nutritional profile.

  16. Flight Measurements to Determine Effect of a Spring-Loaded Tab on Longitudinal Stability of an Airplane

    NASA Technical Reports Server (NTRS)

    Hunter, Paul A.; Reeder, John P.

    1946-01-01

    In conjunction with a program of research on the general problem of stability of airplanes in the climbing condition, tests have been made of a spring-loaded tb which. is referred to as a ?springy tab,? installed on the elevator of a low-wing scout bomber. The tab was arranged to deflect upward with decrease in speed which caused an increase in the pull force required to trim at low speeds and thereby increased the stick-free static longitudinal stability of the airplane. It was found that the springy tab would increase the stick-free stability in all flight conditions, would reduce the danger of inadvertent stalling because of the definite pull force required to stall the airplane with power on, would reduce the effect of center-of-gravity position on stick-free static stability, and would have little effect on the elevator stick forces in accelerated f11ght. Another advantage of the springy tab is that it might be used to provide almost any desired variation of elevator stick force with speed by adjusting the tab hinge-moment characteristics and the variation of spring moment with tab deflection. Unlike the bungee and the bobweight, the springy tab would provide stick-free static stability without requiring a pull force to hold the stick back while taxying. A device similar to the springy tab may be used on the rudder or ailerons to eliminate undesirable trim-force variations with speed.

  17. Process Development for the Design and Manufacturing of Personalizable Mouth Sticks.

    PubMed

    Berger, Veronika M; Pölzer, Stephan; Nussbaum, Gerhard; Ernst, Waltraud; Major, Zoltan

    2017-01-01

    To increase the independence of people with reduced hand/arm functionality, a process to generate personalizable mouth sticks was developed based on the participatory design principle. In a web tool, anybody can choose the geometry and the materials of their mouth piece, stick and tip. Manufacturing techniques (e.g. 3D printing) and materials used in the process are discussed and evaluated.

  18. Beyond Carrots and Sticks: Toward a Transformative Model of Division I Athletics

    ERIC Educational Resources Information Center

    Clubb, Sandy Hatfield

    2012-01-01

    The old expression about the carrot and the stick, which refers to the application of reward and punishment to induce action, dates back to the days when pack mules were used for transportation. The mules would move toward carrots that dangled just ahead of them--and move all the faster because they feared drivers with sticks behind them. In 2012,…

  19. Study on incidence of needle stick injury and factors associated with this problem among medical students.

    PubMed

    Norsayani, Mohamad Yaakob; Noor Hassim, Ismail

    2003-05-01

    Medical students face the threat of needle stick injury with the consequent risk of acquiring blood-borne infection by pathogens such as HIV, Hepatitis B and Hepatitis C while performing their clinical activities in the hospitals. A cross-sectional study was conducted among 417 final year medical students from Universiti Kebangsaan Malaysia (UKM), University Malaya (UM) and Universiti Putra Malaysia (UPM). The aims of the study were to determine the incidence of cases and episodes of needle stick injury among them in the past year. This study was also done to find out the factors that might be associated with the occurrence of this problem. The factors were sociodemographic factors, duration of exposure, level of knowledge of blood-borne diseases and Universal Precaution, perception of risk of blood-borne diseases and level of practice of Universal Precaution. The incidence of needle stick injury among medical students was 14.1% (59 cases). The total number of episodes of needle stick injury was 87 and the incidence of episodes among respondents was high i.e. 20.9%. The highest incidence of episodes of needle stick injury occurred in Obstetric & Gynaecology postings, followed by Medicine and Surgery. For clinical procedures, venepuncture had the highest incidence followed by setting up drips and giving parenteral injections. The results showed the students who had needle stick injury (cases) had lower scores in the practice of Universal Precautions than non-cases (p<0.05). There was a significant association between the level of practice of Universal Precautions and the number of episodes of needle stick injury, i.e. the higher the score for the practice of Universal Precautions, the lower the number of episodes (beta=-2.03 x 10(-2), p<0.05). This study showed that medical students are at risk of needle stick injury and blood-borne infections during their clinical activities while performing procedures on patients especially for those who were poor at practising Universal Precautions. Therefore some preventive measures should be taken by the management of the universities and medical students to avoid the occurrence of these problems.

  20. Slanted joint axes of the stick insect antenna: an adaptation to tactile acuity

    NASA Astrophysics Data System (ADS)

    Mujagic, Samir; Krause, André F.; Dürr, Volker

    2007-04-01

    Like many flightless, obligatory walking insects, the stick insect Carausius morosus makes intensive use of active antennal movements for tactile near range exploration and orientation. The antennal joints of C. morosus have a peculiar oblique and non-orthogonal joint axis arrangement. Moreover, this arrangement is known to differ from that in crickets (Ensifera), locusts (Caelifera) and cockroaches (Blattodea), all of which have an orthogonal joint axis arrangement. Our hypothesis was that the situation found in C. morosus represents an important evolutionary trait of the order of stick and leaf insects (Phasmatodea). If this was true, it should be common to other species of the Phasmatodea. The objective of this comparative study was to resolve this question. We have measured the joint axis orientation of the head scape and scape pedicel joints along with other parameters that affect the tactile efficiency of the antenna. The obtained result was a complete kinematic description of the antenna. This was used to determine the size and location of kinematic out-of-reach zones, which are indicators of tactile acuity. We show that the oblique and non-orthogonal arrangement is common to eight species from six sub-families indicating that it is a synapomorphic character of the Euphasmatodea. This character can improve tactile acuity compared to the situation in crickets, locusts and cockroaches. Finally, because molecular data of a recent study indicate that the Phasmatodea may have evolved as flightless, obligatory walkers, we argue that the antennal joint axis arrangement of the Euphasmatodea reflects an evolutionary adaptation to tactile near range exploration during terrestrial locomotion.

  1. The Physics of Protoplanetesimal Dust Agglomerates. VIII. Microgravity Collisions between Porous SiO{sub 2} Aggregates and Loosely Bound Agglomerates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Whizin, Akbar D.; Colwell, Joshua E.; Blum, Jürgen, E-mail: Akbar.Whizin@ucf.edu

    2017-02-10

    We performed laboratory experiments colliding 0.8–1.0 mm and 1.0–1.6 mm SiO{sub 2} dust aggregates with loosely bound centimeter-sized agglomerates of those aggregates in microgravity. This work builds on previous microgravity laboratory experiments examining the collisional properties of porous loosely bound dust aggregates. In centimeter-sized aggregates, surface forces dominate self-gravity and may play a large role in aggregate growth beyond this size range. We characterize the properties of protoplanetary aggregate analogs to help place constraints on initial formation mechanisms and environments. We determined several important physical characteristics of these aggregates in a large number of low-velocity collisions. We observed low coefficientsmore » of restitution and fragmentation thresholds near 1 m s{sup −1} for 1–2 cm agglomerates, which are in good agreement with previous findings in the literature. We find the accretion efficiency for agglomerates of loosely bound aggregates to be higher than that for just aggregates themselves. We find sticking thresholds of 6.6 ± 2 cm s{sup −1}, somewhat higher than those in similar studies, which have observed few aggregates stick at speeds of under 3 cm s{sup −1}. Even with highly dissipative collisions, loosely bound agglomerates have difficulty accreting beyond centimeter-sized bodies at typical collision speeds in the disk. Our results indicate agglomerates of porous aggregates have slightly higher sticking thresholds than previously thought, allowing possible growth to decimeter-sized bodies if velocities are low enough.« less

  2. Coverage and velocity dependent sticking coefficient and particle emission kinetics in the Cl2gas + Ksolid reaction

    NASA Astrophysics Data System (ADS)

    Hellberg, Lars; Kasemo, Bengt

    Some strongly exothermic and non-adiabatic surface adsorption events, especially those where electronegative molecules adsorb on very electropositive (low work function) surfaces, are accompanied by emission of (exo)electrons, photons, excited atoms and negative ions. The reaction of halogen molecules with halogen surfaces constitute an efficient model system for such studies. We have previously reported data for the emission of negative particles and photons in the zero coverage limit for a range of velocities of Cl2 molecules impinging on cold potassium surfaces as well as the mechanism behind these emission processes. In the present work, we focus on measurements of the kinetics, i.e. the exposure/coverage dependence, of these processes for the same system. Specifically, we present data for, (i) the separated contributions from electrons and Cl- ions of the emitted negative particles, (ii) the photon emission stemming both from excited Potassium atoms and from the equivalent process causing electron emission, (iii) the change of the work function during the initial exposure and, finally, (iv) the sticking coefficient for different Cl2 velocities and exposures.

  3. Tests of a 1/7-Scale Semispan Model of the XB-35 Airplane in the Langley 19-Foot Pressure Tunnel

    NASA Technical Reports Server (NTRS)

    Teplitz, Jerome; Kayten, Gerald G.; Cancro, Patrick A.

    1946-01-01

    A 1/7 scale semispan model of the XB-35 airplane was tested in the Langley 10 foot pressure tunnel, primarily for the purpose of investigating the effectiveness of a leading-edge slot for alleviation of stick-fixed longitudinal instability at high angles of attack caused by early tip stalling and a device for relief of stick-free instability caused by elevon up-floating tendencies at high angles of attack. Results indicated that the slot was not adequate to provide the desired improvement in stick-fixed stability. The tab-flipper device provided improvement in stick-free stability abd two of the linkage combinations tested gave satisfactory variations of control force with airspeed for all conditions except that in which the wing-tip "pitch-control" flap was fully deflected. However, the improvement in control force characteristics was accompanied by a detrimental effect on stick-fixed stability because of the pitching moments produced by the elevon tab deflection.

  4. Stick-slip instabilities in sheared granular flow: The role of friction and acoustic vibrations.

    PubMed

    Lieou, Charles K C; Elbanna, Ahmed E; Langer, J S; Carlson, J M

    2015-08-01

    We propose a theory of shear flow in dense granular materials. A key ingredient of the theory is an effective temperature that determines how the material responds to external driving forces such as shear stresses and vibrations. We show that, within our model, friction between grains produces stick-slip behavior at intermediate shear rates, even if the material is rate strengthening at larger rates. In addition, externally generated acoustic vibrations alter the stick-slip amplitude, or suppress stick-slip altogether, depending on the pressure and shear rate. We construct a phase diagram that indicates the parameter regimes for which stick-slip occurs in the presence and absence of acoustic vibrations of a fixed amplitude and frequency. These results connect the microscopic physics to macroscopic dynamics and thus produce useful information about a variety of granular phenomena, including rupture and slip along earthquake faults, the remote triggering of instabilities, and the control of friction in material processing.

  5. Acute effects of The Stick on strength, power, and flexibility.

    PubMed

    Mikesky, Alan E; Bahamonde, Rafael E; Stanton, Katie; Alvey, Thurman; Fitton, Tom

    2002-08-01

    The Stick is a muscle massage device used by athletes, particularly track athletes, to improve performance. The purpose of this project was to assess the acute effects of The Stick on muscle strength, power, and flexibility. Thirty collegiate athletes consented to participate in a 4-week, double-blind study, which consisted of 4 testing sessions (1 familiarization and 3 data collection) scheduled 1 week apart. During each testing session subjects performed 4 measures in the following sequence: hamstring flexibility, vertical jump, flying-start 20-yard dash, and isokinetic knee extension at 90 degrees x s(-1). Two minutes of randomly assigned intervention treatment (visualization [control], mock insensible electrical stimulation [placebo], or massage using The Stick [experimental]) was performed immediately prior to each performance measure. Statistical analyses involved single-factor repeated measures analysis of variance (ANOVA) with Fisher's Least Significant Difference post-hoc test. None of the variables measured showed an acute improvement (p < or = 0.05) immediately following treatment with The Stick.

  6. Quantum dynamics of hydrogen atoms on graphene. II. Sticking.

    PubMed

    Bonfanti, Matteo; Jackson, Bret; Hughes, Keith H; Burghardt, Irene; Martinazzo, Rocco

    2015-09-28

    Following our recent system-bath modeling of the interaction between a hydrogen atom and a graphene surface [Bonfanti et al., J. Chem. Phys. 143, 124703 (2015)], we present the results of converged quantum scattering calculations on the activated sticking dynamics. The focus of this study is the collinear scattering on a surface at zero temperature, which is treated with high-dimensional wavepacket propagations with the multi-configuration time-dependent Hartree method. At low collision energies, barrier-crossing dominates the sticking and any projectile that overcomes the barrier gets trapped in the chemisorption well. However, at high collision energies, energy transfer to the surface is a limiting factor, and fast H atoms hardly dissipate their excess energy and stick on the surface. As a consequence, the sticking coefficient is maximum (∼0.65) at an energy which is about one and half larger than the barrier height. Comparison of the results with classical and quasi-classical calculations shows that quantum fluctuations of the lattice play a primary role in the dynamics. A simple impulsive model describing the collision of a classical projectile with a quantum surface is developed which reproduces the quantum results remarkably well for all but the lowest energies, thereby capturing the essential physics of the activated sticking dynamics investigated.

  7. Quantum dynamics of hydrogen atoms on graphene. II. Sticking

    NASA Astrophysics Data System (ADS)

    Bonfanti, Matteo; Jackson, Bret; Hughes, Keith H.; Burghardt, Irene; Martinazzo, Rocco

    2015-09-01

    Following our recent system-bath modeling of the interaction between a hydrogen atom and a graphene surface [Bonfanti et al., J. Chem. Phys. 143, 124703 (2015)], we present the results of converged quantum scattering calculations on the activated sticking dynamics. The focus of this study is the collinear scattering on a surface at zero temperature, which is treated with high-dimensional wavepacket propagations with the multi-configuration time-dependent Hartree method. At low collision energies, barrier-crossing dominates the sticking and any projectile that overcomes the barrier gets trapped in the chemisorption well. However, at high collision energies, energy transfer to the surface is a limiting factor, and fast H atoms hardly dissipate their excess energy and stick on the surface. As a consequence, the sticking coefficient is maximum (˜0.65) at an energy which is about one and half larger than the barrier height. Comparison of the results with classical and quasi-classical calculations shows that quantum fluctuations of the lattice play a primary role in the dynamics. A simple impulsive model describing the collision of a classical projectile with a quantum surface is developed which reproduces the quantum results remarkably well for all but the lowest energies, thereby capturing the essential physics of the activated sticking dynamics investigated.

  8. A comparison of muscle activity in concentric and counter movement maximum bench press.

    PubMed

    van den Tillaar, Roland; Ettema, Gertjan

    2013-01-01

    The purpose of this study was to compare the kinematics and muscle activation patterns of regular free-weight bench press (counter movement) with pure concentric lifts in the ascending phase of a successful one repetition maximum (1-RM) attempt in the bench press. Our aim was to evaluate if diminishing potentiation could be the cause of the sticking region. Since diminishing potentiation cannot occur in pure concentric lifts, the occurrence of a sticking region in this type of muscle actions would support the hypothesis that the sticking region is due to a poor mechanical position. Eleven male participants (age 21.9 ± 1.7 yrs, body mass 80.7 ± 10.9 kg, body height 1.79 ± 0.07 m) conducted 1-RM lifts in counter movement and in pure concentric bench presses in which kinematics and EMG activity were measured. In both conditions, a sticking region occurred. However, the start of the sticking region was different between the two bench presses. In addition, in four of six muscles, the muscle activity was higher in the counter movement bench press compared to the concentric one. Considering the findings of the muscle activity of six muscles during the maximal lifts it was concluded that the diminishing effect of force potentiation, which occurs in the counter movement bench press, in combination with a delayed muscle activation unlikely explains the existence of the sticking region in a 1-RM bench press. Most likely, the sticking region is the result of a poor mechanical force position.

  9. Implications of basal micro-earthquakes and tremor for ice stream mechanics: Stick-slip basal sliding and till erosion

    NASA Astrophysics Data System (ADS)

    Barcheck, C. Grace; Tulaczyk, Slawek; Schwartz, Susan Y.; Walter, Jacob I.; Winberry, J. Paul

    2018-03-01

    The Whillans Ice Plain (WIP) is unique among Antarctic ice streams because it moves by stick-slip. The conditions allowing stick-slip and its importance in controlling ice dynamics remain uncertain. Local basal seismicity previously observed during unstable slip is a clue to the mechanism of ice stream stick-slip and a window into current basal conditions, but the spatial extent and importance of this basal seismicity are unknown. We analyze data from a 2010-2011 ice-plain-wide seismic and GPS network to show that basal micro-seismicity correlates with large-scale patterns in ice stream slip behavior: Basal seismicity is common where the ice moves the least between unstable slip events, with small discrete basal micro-earthquakes happening within 10s of km of the central stick-slip nucleation area and emergent basal tremor occurring downstream of this area. Basal seismicity is largely absent in surrounding areas, where inter-slip creep rates are high. The large seismically active area suggests that a frictional sliding law that can accommodate stick-slip may be appropriate for ice stream beds on regional scales. Variability in seismic behavior over inter-station distances of 1-10 km indicates heterogeneity in local bed conditions and frictional complexity. WIP unstable slips may nucleate when stick-slip basal earthquake patches fail over a large area. We present a conceptual model in which basal seismicity results from slip-weakening frictional failure of over-consolidated till as it is eroded and mobilized into deforming till.

  10. A Comparison of Muscle Activity in Concentric and Counter Movement Maximum Bench Press

    PubMed Central

    van den Tillaar, Roland; Ettema, Gertjan

    2013-01-01

    The purpose of this study was to compare the kinematics and muscle activation patterns of regular free-weight bench press (counter movement) with pure concentric lifts in the ascending phase of a successful one repetition maximum (1-RM) attempt in the bench press. Our aim was to evaluate if diminishing potentiation could be the cause of the sticking region. Since diminishing potentiation cannot occur in pure concentric lifts, the occurrence of a sticking region in this type of muscle actions would support the hypothesis that the sticking region is due to a poor mechanical position. Eleven male participants (age 21.9 ± 1.7 yrs, body mass 80.7 ± 10.9 kg, body height 1.79 ± 0.07 m) conducted 1-RM lifts in counter movement and in pure concentric bench presses in which kinematics and EMG activity were measured. In both conditions, a sticking region occurred. However, the start of the sticking region was different between the two bench presses. In addition, in four of six muscles, the muscle activity was higher in the counter movement bench press compared to the concentric one. Considering the findings of the muscle activity of six muscles during the maximal lifts it was concluded that the diminishing effect of force potentiation, which occurs in the counter movement bench press, in combination with a delayed muscle activation unlikely explains the existence of the sticking region in a 1-RM bench press. Most likely, the sticking region is the result of a poor mechanical force position. PMID:24235985

  11. Human stick balancing: Tuning Lèvy flights to improve balance control

    NASA Astrophysics Data System (ADS)

    Cabrera, Juan Luis; Milton, John G.

    2004-09-01

    State-dependent, or parametric, noise is an essential component of the neural control mechanism for stick balancing at the fingertip. High-speed motion analysis in three dimensions demonstrates that the controlling movements made by the fingertip during stick balancing can be described by a Lévy flight. The Lévy index, α, is approximately 0.9; a value close to optimal for a random search. With increased skill, the index α does not change. However, the tails of the Lévy distribution become broader. These observations suggest a Lévy flight that is truncated by the properties of the nervous and musculoskeletal system; the truncation decreasing as skill level increases. Measurements of the cross-correlation between the position of the tip of the stick and the fingertip demonstrate that the role of closed-loop feedback changes with increased skill. Moreover, estimation of the neural latencies for stick balancing show that for a given stick length, the latency increases with skill level. It is suggested that the neural control for stick balancing involves a mechanism in which brief intervals of consciously generated, corrective movements alternate with longer intervals of prediction-free control. With learning the truncation of the Lévy flight becomes better optimized for balance control and hence the time between successive conscious corrections increases. These observations provide the first evidence that changes in a Lévy flight may have functional significance for the nervous system. This work has implications for the control of balancing problems ranging from falling in the elderly to the design of two-legged robots and earthquake proof buildings.

  12. [Correlation between physical characteristics of sticks and quality of traditional Chinese medicine pills prepared by plastic molded method].

    PubMed

    Wang, Ling; Xian, Jiechen; Hong, Yanlong; Lin, Xiao; Feng, Yi

    2012-05-01

    To quantify the physical characteristics of sticks of traditional Chinese medicine (TCM) honeyed pills prepared by the plastic molded method and the correlation of adhesiveness and plasticity-related parameters of sticks and quality of pills, in order to find major parameters and the appropriate range impacting pill quality. Sticks were detected by texture analyzer for their physical characteristic parameters such as hardness and compression action, and pills were observed by visual evaluation for their quality. The correlation of both data was determined by the stepwise discriminant analysis. Stick physical characteristic parameter l(CD) can exactly depict the adhesiveness, with the discriminant equation of Y0 - Y1 = 6.415 - 41.594l(CD). When Y0 < Y1, pills were scattered well; when Y0 > Y1, pills were adhesive with each other. Pills' physical characteristic parameters l(CD) and l(AC), Ar, Tr can exactly depict smoothness of pills, with the discriminant equation of Z0 - Z1 = -195.318 + 78.79l(AC) - 3 258. 982Ar + 3437.935Tr. When Z0 < Z1, pills were smooth on surface. When Z0 > Z1, pills were rough on surface. The stepwise discriminant analysis is made to show the obvious correlation between key physical characteristic parameters l(CD) and l(AC), Ar, Tr of sticks and appearance quality of pills, defining the molding process for preparing pills by the plastic molded and qualifying ranges of key physical characteristic parameters characterizing intermediate sticks, in order to provide theoretical basis for prescription screening and technical parameter adjustment for pills.

  13. Numerical Simulations of Slow Stick Slip Events with PFC, a DEM Based Code

    NASA Astrophysics Data System (ADS)

    Ye, S. H.; Young, R. P.

    2017-12-01

    Nonvolcanic tremors around subduction zone have become a fascinating subject in seismology in recent years. Previous studies have shown that the nonvolcanic tremor beneath western Shikoku is composed of low frequency seismic waves overlapping each other. This finding provides direct link between tremor and slow earthquakes. Slow stick slip events are considered to be laboratory scaled slow earthquakes. Slow stick slip events are traditionally studied with direct shear or double direct shear experiment setup, in which the sliding velocity can be controlled to model a range of fast and slow stick slips. In this study, a PFC* model based on double direct shear is presented, with a central block clamped by two side blocks. The gauge layers between the central and side blocks are modelled as discrete fracture networks with smooth joint bonds between pairs of discrete elements. In addition, a second model is presented in this study. This model consists of a cylindrical sample subjected to triaxial stress. Similar to the previous model, a weak gauge layer at a 45 degrees is added into the sample, on which shear slipping is allowed. Several different simulations are conducted on this sample. While the confining stress is maintained at the same level in different simulations, the axial loading rate (displacement rate) varies. By varying the displacement rate, a range of slipping behaviour, from stick slip to slow stick slip are observed based on the stress-strain relationship. Currently, the stick slip and slow stick slip events are strictly observed based on the stress-strain relationship. In the future, we hope to monitor the displacement and velocity of the balls surrounding the gauge layer as a function of time, so as to generate a synthetic seismogram. This will allow us to extract seismic waveforms and potentially simulate the tremor-like waves found around subduction zones. *Particle flow code, a discrete element method based numerical simulation code developed by Itasca Inc.

  14. On Motion Planning with Uncertainty. Revised.

    DTIC Science & Technology

    1984-01-01

    drift to the right, sticking at the right corner. See Fig. 1.6. Given the uncertainty in the position sensor, it is impossible to execute corrective ...action once * sticking is detected. This is because the corrective action depends on knowing the side at which sticking occurred. Worse than being...unable to correct errors should they occur, is the inability to detect success. In the given example, it is possible that the peg may move smoothly into

  15. Factors affecting the sticking of insects on modified aircraft wings

    NASA Technical Reports Server (NTRS)

    Yi, O.; Chitsaz-Z, M. R.; Eiss, N. S.; Wightman, J. P.

    1987-01-01

    Past studies have shown that the surface energy of a polymer coating has an important effect on the sticking of insects to the surface. However, mechanical properties of polymer coatings such as elasticity may also be important. A further study is suggested using polymer coatings of known surface energy and modulus so that a better understanding of the mechanism of the sticking of insects to surfaces can be achieved. As the first step for the study, surface analysis and road tests were performed using elastomers having different energies and different moduli. The number of insects sticking to each elastomer was counted and compared from sample to sample and with a control (aluminum). An average height moment was also calculated and comparisons made between samples.

  16. Effects of asperity contact on stick-slip dynamics

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Tetsuo

    2017-04-01

    It is believed that asperity contact plays an important role in fricton, in particular in onset of dynamic slip or stick-slip motions. However, there remains very few studies controling asperities and observing their effects on mascoscopic stick-slip behavior or frictional constitutive laws. Here we perform stick-slip friction experiments between compliant gels with well-controlled asperity shape/size/configurations by molding technique. We find that, as curvature radius of the asperity becomes larger and the normal stress becomes smaller, velocity dependence turns from rate-strengthening to rate-weakening and accordingly, frictional behavior transitions from steady sliding, slow slip to fast slip. In this talk, we discuss the asperity size effects based on microscopic/macroscopic observations as well as a theoretical argument.

  17. Efficiency and large deviations in time-asymmetric stochastic heat engines

    DOE PAGES

    Gingrich, Todd R.; Rotskoff, Grant M.; Vaikuntanathan, Suriyanarayanan; ...

    2014-10-24

    In a stochastic heat engine driven by a cyclic non-equilibrium protocol, fluctuations in work and heat give rise to a fluctuating efficiency. Using computer simulations and tools from large deviation theory, we have examined these fluctuations in detail for a model two-state engine. We find in general that the form of efficiency probability distributions is similar to those described by Verley et al (2014 Nat. Commun. 5 4721), in particular featuring a local minimum in the long-time limit. In contrast to the time-symmetric engine protocols studied previously, however, this minimum need not occur at the value characteristic of a reversible Carnot engine. Furthermore, while the local minimum may reside at the global minimum of a large deviation rate function, it does not generally correspond to the least likely efficiency measured over finite time. Lastly, we introduce a general approximation for the finite-time efficiency distribution,more » $$P(\\eta )$$, based on large deviation statistics of work and heat, that remains very accurate even when $$P(\\eta )$$ deviates significantly from its large deviation form.« less

  18. Balancing with Vibration: A Prelude for “Drift and Act” Balance Control

    PubMed Central

    Milton, John G.; Ohira, Toru; Cabrera, Juan Luis; Fraiser, Ryan M.; Gyorffy, Janelle B.; Ruiz, Ferrin K.; Strauss, Meredith A.; Balch, Elizabeth C.; Marin, Pedro J.; Alexander, Jeffrey L.

    2009-01-01

    Stick balancing at the fingertip is a powerful paradigm for the study of the control of human balance. Here we show that the mean stick balancing time is increased by about two-fold when a subject stands on a vibrating platform that produces vertical vibrations at the fingertip (0.001 m, 15–50 Hz). High speed motion capture measurements in three dimensions demonstrate that vibration does not shorten the neural latency for stick balancing or change the distribution of the changes in speed made by the fingertip during stick balancing, but does decrease the amplitude of the fluctuations in the relative positions of the fingertip and the tip of the stick in the horizontal plane, A(x,y). The findings are interpreted in terms of a time-delayed “drift and act” control mechanism in which controlling movements are made only when controlled variables exceed a threshold, i.e. the stick survival time measures the time to cross a threshold. The amplitude of the oscillations produced by this mechanism can be decreased by parametric excitation. It is shown that a plot of the logarithm of the vibration-induced increase in stick balancing skill, a measure of the mean first passage time, versus the standard deviation of the A(x,y) fluctuations, a measure of the distance to the threshold, is linear as expected for the times to cross a threshold in a stochastic dynamical system. These observations suggest that the balanced state represents a complex time–dependent state which is situated in a basin of attraction that is of the same order of size. The fact that vibration amplitude can benefit balance control raises the possibility of minimizing risk of falling through appropriate changes in the design of footwear and roughness of the walking surfaces. PMID:19841741

  19. Human stick balancing: tuning Lèvy flights to improve balance control.

    PubMed

    Cabrera, Juan Luis; Milton, John G

    2004-09-01

    State-dependent, or parametric, noise is an essential component of the neural control mechanism for stick balancing at the fingertip. High-speed motion analysis in three dimensions demonstrates that the controlling movements made by the fingertip during stick balancing can be described by a Lèvy flight. The Lèvy index, alpha, is approximately 0.9; a value close to optimal for a random search. With increased skill, the index alpha does not change. However, the tails of the Lèvy distribution become broader. These observations suggest a Lèvy flight that is truncated by the properties of the nervous and musculoskeletal system; the truncation decreasing as skill level increases. Measurements of the cross-correlation between the position of the tip of the stick and the fingertip demonstrate that the role of closed-loop feedback changes with increased skill. Moreover, estimation of the neural latencies for stick balancing show that for a given stick length, the latency increases with skill level. It is suggested that the neural control for stick balancing involves a mechanism in which brief intervals of consciously generated, corrective movements alternate with longer intervals of prediction-free control. With learning the truncation of the Lèvy flight becomes better optimized for balance control and hence the time between successive conscious corrections increases. These observations provide the first evidence that changes in a Lèvy flight may have functional significance for the nervous system. This work has implications for the control of balancing problems ranging from falling in the elderly to the design of two-legged robots and earthquake proof buildings. Copyright 2004 American Institute of Physics

  20. Simple and easy assessment of falling risk in the elderly by functional reach test using elastic stick.

    PubMed

    Demura, Shin-Ichi; Yamada, Takayoshi

    2007-10-01

    Dynamic balance ability related to maintaining postural stability during movement is closely tied to fall risk in the elderly. The functional reach (FR) test has been developed to evaluate their dynamic balance. Although a simple and new FR test using an elastic stick has been proposed by modifying the above original FR test, the abilities related to both FR tests are judged to differ because of the large difference in the testing method. This study aimed to compare center of gravity fluctuation, muscle activity and functional reach distance as measured by the original FR test and the elastic stick FR test. First, reach distance, back/forth and right/left moving distance of the center of gravity, and activity of the lower leg muscles (soleus and tibialis anterior) were compared between both tests based on data obtained from 30 young male adults. All parameters except for the right/left moving distance were significantly larger in the elastic stick FR test. Next, the reach distance was examined in both FR tests using 53 elderly subjects; it was significantly longer in the elastic stick FR test, but showed no significant sex difference. The reach distance in both tests was significantly shorter (about 7 cm) in the elderly than in young adults. In conclusion, the elastic stick FR test involves greater leg muscle strength exertion and forward transferring of the center of gravity as compared with the original FR test. Because the elastic stick FR test relates largely to leg muscle function and equilibrium function, it may be more useful for evaluating the dynamic balance ability of the elderly.

  1. Theoretical and experimental research on the phenomenon of stick-slip at traction railway vehicles

    NASA Astrophysics Data System (ADS)

    Sebesan, Ioan; Manea, Ion; Spiroiu, Marius Adrian; Arsene, Sorin

    2018-01-01

    The stick-slip phenomenon may occur when the limit adhesion force is exceeded at one of the motor axles of the vehicle. In the present paper is analysed the physical phenomenon stick-slip, the conditions for its occurrence and the mechanical model recommended for the study of the phenomenon. Regarding the experimental research, it is presented the stand built in the laboratory of the Rolling Stock Department at Politehnica University of Bucharest.

  2. New PDC bit design reduces vibrational problems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mensa-Wilmot, G.; Alexander, W.L.

    1995-05-22

    A new polycrystalline diamond compact (PDC) bit design combines cutter layout, load balancing, unsymmetrical blades and gauge pads, and spiraled blades to reduce problematic vibrations without limiting drilling efficiency. Stabilization improves drilling efficiency and also improves dull characteristics for PDC bits. Some PDC bit designs mitigate one vibrational mode (such as bit whirl) through drilling parameter manipulation yet cause or excite another vibrational mode (such as slip-stick). An alternative vibration-reducing concept which places no limitations on the operational environment of a PDC bit has been developed to ensure optimization of the bit`s available mechanical energy. The paper discusses bit stabilization,more » vibration reduction, vibration prevention, cutter arrangement, load balancing, blade layout, spiraled blades, and bit design.« less

  3. Incense and joss stick making in small household factories, Thailand.

    PubMed

    Siripanich, S; Siriwong, W; Keawrueang, P; Borjan, M; Robson, M

    2014-07-01

    Incense and joss stick are generally used in the world. Most products were made in small household factories. There are many environmental and occupational hazards in these factories. To evaluate the workplace environmental and occupational hazards in small household incense and joss stick factories in Roi-Et, Thailand. Nine small household factories in rural areas of Roi-Et, Thailand, were studied. Dust concentration and small aerosol particles were counted through real time exposure monitoring. The inductively coupled plasma optical emission spectrometry (ICP-OES) was used for quantitative measurement of heavy metal residue in incense products. Several heavy metals were found in dissolved dye and joss sticks. Those included barium, manganese, and lead. Rolling and shaking processes produced the highest concentration of dust and aerosols. Only 3.9% of female workers used personal protection equipment. Dust and chemicals were major threats in small household incense and joss stick factories in Thailand. Increasing awareness towards using personal protection equipment and emphasis on elimination of environmental workplace hazards should be considered to help the workers of this industry.

  4. Multiscale treatment of theoretical mechanisms for the protection of hydrogel surfaces from adhesive forces

    NASA Astrophysics Data System (ADS)

    Sokoloff, J. B.

    2014-09-01

    One role of a lubricant is to prevent wear of two surfaces in contact, which is likely to be the result of adhesive forces that cause a pair of asperities belonging to two surfaces in contact to stick together. Such adhesive sticking of asperities can occur both for sliding surfaces and for surfaces which are pressed together and then pulled apart. The latter situation, for example, is important for contact lenses, as prevention of sticking reduces possible damage to the cornea as the lenses are inserted and removed from the eye. Contact lenses are made from both neutral and polyelectrolyte hydrogels. It is demonstrated here that sticking of neutral hydrogels can be prevented by repulsive forces between asperities in contact, resulting from polymers attached to the gel surface but not linked with each other. For polyelectrolyte hydrogels, it is shown that osmotic pressure due to counterions, held at the interface between asperities in contact by the electrostatic attraction between the ions and the fixed charges in the gel, can provide a sufficiently strong repulsive force to prevent adhesive sticking of small-length-scale asperities.

  5. Cultural Adaptation of the Portuguese Version of the “Sniffin’ Sticks” Smell Test: Reliability, Validity, and Normative Data

    PubMed Central

    Ribeiro, João Carlos; Simões, João; Silva, Filipe; Silva, Eduardo D.; Hummel, Cornelia; Hummel, Thomas; Paiva, António

    2016-01-01

    The cross-cultural adaptation and validation of the Sniffin`Sticks test for the Portuguese population is described. Over 270 people participated in four experiments. In Experiment 1, 67 participants rated the familiarity of presented odors and seven descriptors of the original test were adapted to a Portuguese context. In Experiment 2, the Portuguese version of Sniffin`Sticks test was administered to 203 healthy participants. Older age, male gender and active smoking status were confirmed as confounding factors. The third experiment showed the validity of the Portuguese version of Sniffin`Sticks test in discriminating healthy controls from patients with olfactory dysfunction. In Experiment 4, the test-retest reliability for both the composite score (r71 = 0.86) and the identification test (r71 = 0.62) was established (p<0.001). Normative data for the Portuguese version of Sniffin`Sticks test is provided, showing good validity and reliability and effectively distinguishing patients from healthy controls with high sensitivity and specificity. The Portuguese version of Sniffin`Sticks test identification test is a clinically suitable screening tool in routine outpatient Portuguese settings. PMID:26863023

  6. Apparent Dependence of Rate- and State-Dependent Friction Parameters on Loading Velocity and Cumulative Displacement Inferred from Large-Scale Biaxial Friction Experiments

    NASA Astrophysics Data System (ADS)

    Urata, Yumi; Yamashita, Futoshi; Fukuyama, Eiichi; Noda, Hiroyuki; Mizoguchi, Kazuo

    2017-06-01

    We investigated the constitutive parameters in the rate- and state-dependent friction (RSF) law by conducting numerical simulations, using the friction data from large-scale biaxial rock friction experiments for Indian metagabbro. The sliding surface area was 1.5 m long and 0.5 m wide, slid for 400 s under a normal stress of 1.33 MPa at a loading velocity of either 0.1 or 1.0 mm/s. During the experiments, many stick-slips were observed and those features were as follows. (1) The friction drop and recurrence time of the stick-slip events increased with cumulative slip displacement in an experiment before which the gouges on the surface were removed, but they became almost constant throughout an experiment conducted after several experiments without gouge removal. (2) The friction drop was larger and the recurrence time was shorter in the experiments with faster loading velocity. We applied a one-degree-of-freedom spring-slider model with mass to estimate the RSF parameters by fitting the stick-slip intervals and slip-weakening curves measured based on spring force and acceleration of the specimens. We developed an efficient algorithm for the numerical time integration, and we conducted forward modeling for evolution parameters ( b) and the state-evolution distances (L_{{c}}), keeping the direct effect parameter ( a) constant. We then identified the confident range of b and L_{{c}} values. Comparison between the results of the experiments and our simulations suggests that both b and L_{{c}} increase as the cumulative slip displacement increases, and b increases and L_{{c}} decreases as the loading velocity increases. Conventional RSF laws could not explain the large-scale friction data, and more complex state evolution laws are needed.

  7. The past, present, and future of hockey-stick-shaped liquid crystals

    NASA Astrophysics Data System (ADS)

    Choi, E.-Joon

    2014-02-01

    Recently, the liquid crystalline materials with a bent-core mesogen have attracted attentions because their interesting properties such as polarity and biaxiality of the mesophase. There are several types of bent-core mesogenic structures have been reported, for instance, banana-shaped, V-shaped molecules, boomerang-shaped, hockey stick-shaped, and Yshaped molecules. In this study, the liquid crystals and the reactive mesogens with the hockey-stick shaped mesogens will be described concerning with the structure-property relationship.

  8. The mechanics of stick-slip

    USGS Publications Warehouse

    Byerlee, J.D.

    1970-01-01

    Physical mechanisms that have been proposed to explain the occurrence of stick-slip motion during frictional sliding have been examined in the light of results obtained from experiments with rocks and brittle minerals. An instability caused by sudden brittle fracture of locked regions on surfaces in contact is the most likely explanation for stick-slip during dry frictional sliding of brittle rocks at room temperature. Areas requiring further study and the uncertainties in applying the results of laboratory experiments to earthquake studies are emphasized. ?? 1970.

  9. The Interactive Effect of Diversification and Farming Scale on Productivity of Family Farm:Taking Rice Cultivation as An Example

    NASA Astrophysics Data System (ADS)

    Wei, Zhou

    2017-05-01

    Based on the diversification and cultivation scale, the rice cropping data of rural fixed observation points in 2011 were selected and the effect of diversification degree on rice productivity was analyzed by the Tobit model. The empirical results of the model show that diversification of sample farm will lead to loss of rice production efficiency. With the increase of rice planting scale, the loss of rice production efficiency will need to be further increased by diversification. Thus, we should stick to the family farm of specialized production operation. The transfer of land, the price and quantity of leasing, respecting the law of the market; the raising of funds can be considered non-subsidized capital market financing to help, while maintaining a certain degree of diversification, to avoid idle assets, low resource efficiency loss.

  10. The Aerodynamic Characteristics in Pitch of a 1/15-Scale Model of the Grumman F11F-1 Airplane at Mach Numbers of 1.41, 1.61, and 2.01, TED No. NACA DE 390

    NASA Technical Reports Server (NTRS)

    Driver, Cornelius

    1956-01-01

    Tests have been made in the Langley 4- by 4-foot supersonic pressure tunnel at Mach numbers of 1.41, 1.61, and 2.01 to determine the static longitudinal stability and control characteristics of various arrangements of the Grumman F11F-1 airplane. Tests were made of the complete model and various combinations of its component parts and, in addition, the effects of various body modifications, a revised vertical tail, and wing fences on the longitudinal characteristics were determined. The results indicate that for a horizontal-tail incidence of -10 deg the trim lift coefficient varied from 0.29 at a Mach number of 1.61 to 0.23 at a Mach number of 2.01 with a corresponding decrease in lift-drag trim from 3.72 to 3.15. Stick-position instability was indicated in the low-supersonic-speed range. A photographic-type nose modification resulted in slightly higher values of minimum drag coefficient but did not significantly affect the static stability or lift-curve slope. The minimum drag coefficient for the complete model with the production nose remained essentially constant at 0.047 throughout the Mach number range investigated.

  11. How Can I Lose Weight Safely?

    MedlinePlus

    ... people find that eating a couple of small snacks throughout the day helps them to make healthy choices at meals. Stick a couple of healthy snacks (carrot sticks, whole-grain pretzels, or a piece ...

  12. Mechanization of and experience with a triplex fly-by-wire backup control system

    NASA Technical Reports Server (NTRS)

    Lock, W. P.; Petersen, W. R.; Whitman, G. B.

    1976-01-01

    A redundant three axis analog control system was designed and developed to back up a digital fly by wire control system for an F-8C airplane. The mechanization and operational experience with the backup control system, the problems involved in synchronizing it with the primary system, and the reliability of the system are discussed. The backup control system was dissimilar to the primary system, and it provided satisfactory handling through the flight envelope evaluated. Limited flight tests of a variety of control tasks showed that control was also satisfactory when the backup control system was controlled by a minimum displacement (force) side stick. The operational reliability of the F-8 digital fly by wire control system was satisfactory, with no unintentional downmodes to the backup control system in flight. The ground and flight reliability of the system's components is discussed.

  13. An Investigation into III-V Compounds to Reach 20% Efficiency with Minimum Cell Thickness in Ultrathin-Film Solar Cells

    NASA Astrophysics Data System (ADS)

    Haque, K. A. S. M. Ehteshamul; Galib, Md. Mehedi Hassan

    2013-10-01

    III-V single-junction solar cells have already achieved very high efficiency levels. However, their use in terrestrial applications is limited by the high fabrication cost. High-efficiency, ultrathin-film solar cells can effectively solve this problem, as their material requirement is minimum. This work presents a comparison among several III-V compounds that have high optical absorption capability as well as optimum bandgap (around 1.4 eV) for use as solar cell absorbers. The aim is to observe and compare the ability of these materials to reach a target efficiency level of 20% with minimum possible cell thickness. The solar cell considered has an n-type ZnSe window layer, an n-type Al0.1Ga0.9As emitter layer, and a p-type Ga0.5In0.5P back surface field (BSF) layer. Ge is used as the substrate. In the initial design, a p-type InP base was sandwiched between the emitter and the BSF layer, and the design parameters for the device were optimized by analyzing the simulation outcomes with ADEPT/F, a one-dimensional (1D) simulation tool. Then, the minimum cell thickness that achieves 20% efficiency was determined by observing the efficiency variation with cell thickness. Afterwards, the base material was changed to a few other selected III-V compounds, and for each case, the minimum cell thickness was determined in a similar manner. Finally, these cell thickness values were compared and analyzed to identify more effective base layer materials for III-V single-junction solar cells.

  14. Bayesian nonparametric regression with varying residual density

    PubMed Central

    Pati, Debdeep; Dunson, David B.

    2013-01-01

    We consider the problem of robust Bayesian inference on the mean regression function allowing the residual density to change flexibly with predictors. The proposed class of models is based on a Gaussian process prior for the mean regression function and mixtures of Gaussians for the collection of residual densities indexed by predictors. Initially considering the homoscedastic case, we propose priors for the residual density based on probit stick-breaking (PSB) scale mixtures and symmetrized PSB (sPSB) location-scale mixtures. Both priors restrict the residual density to be symmetric about zero, with the sPSB prior more flexible in allowing multimodal densities. We provide sufficient conditions to ensure strong posterior consistency in estimating the regression function under the sPSB prior, generalizing existing theory focused on parametric residual distributions. The PSB and sPSB priors are generalized to allow residual densities to change nonparametrically with predictors through incorporating Gaussian processes in the stick-breaking components. This leads to a robust Bayesian regression procedure that automatically down-weights outliers and influential observations in a locally-adaptive manner. Posterior computation relies on an efficient data augmentation exact block Gibbs sampler. The methods are illustrated using simulated and real data applications. PMID:24465053

  15. Full-scale Wind-tunnel and Flight Tests of a Fairchild 22 Airplane Equipped with External-airfoil Flaps

    NASA Technical Reports Server (NTRS)

    Reed, Warren D; Clay, William C

    1937-01-01

    Wind-tunnel and flight tests have been made of a Fairchild 22 airplane equipped with a wing having external-airfoil flaps that also perform the function of ailerons. Lift, drag, and pitching-moment coefficients of the airplane with several flap settings, and the rolling- and yawing-moment coefficients with the flaps deflected as ailerons were measured in the full-scale tunnel with the horizontal tail surfaces and propeller removed. The effect of the flaps on the low speed and on the take-off and landing characteristics, the effectiveness of flaps when used as ailerons, and the forces required to operate them as ailerons were determined in flight. The wind-tunnel tests showed that the flaps increased the maximum lift coefficient of the airplane from 1.51 with the flap in the minimum drag position to 2.12 with the flap in the minimum drag position to 2.12 with the flap deflected 30 degrees. In the flight tests the minimum speed decreased from 46.8 miles per hour with the flaps up to 41.3 miles per hour with the flaps deflected. The required take-off run to attain a height of 50 feet was reduced from 820 to 750 feet and the landing run from a height of 50 feet was reduced from 930 to 480 feet. The flaps for this installation gave lateral control that was not entirely satisfactory. Their rolling action was good but the adverse yaw resulting from their use was greater than is considerable, and the stick forces required to operate them increased too rapidly with speed.

  16. Listening in on Friction: Stick-Slip Acoustical Signatures in Velcro

    NASA Astrophysics Data System (ADS)

    Hurtado Parra, Sebastian; Morrow, Leslie; Radziwanowski, Miles; Angiolillo, Paul

    2013-03-01

    The onset of kinetic friction and the possible resulting stick-slip motion remain mysterious phenomena. Moreover, stick-slip dynamics are typically accompanied by acoustic bursts that occur temporally with the slip event. The dry sliding dynamics of the hook-and-loop system, as exemplified by Velcro, manifest stick-slip behavior along with audible bursts that are easily micrphonically collected. Synchronized measurements of the friction force and acoustic emissions were collected as hooked Velcro was driven at constant velocity over a bed of looped Velcro in an anechoic chamber. Not surprising, the envelope of the acoustic bursts maps well onto the slip events of the friction force time series and the intensity of the bursts trends with the magnitude of the difference of the friction force during a stick-slip event. However, the analysis of the acoustic emission can serve as a sensitive tool for revealing some of the hidden details of the evolution of the transition from static to kinetic friction. For instance, small acoustic bursts are seen prior to the Amontons-Coulomb threshold, signaling precursor events prior to the onset of macroscopically observed motion. Preliminary spectral analysis of the acoustic emissions including intensity-frequency data will be presented.

  17. All great ape species (Gorilla gorilla, Pan paniscus, Pan troglodytes, Pongo abelii) and two-and-a-half-year-old children (Homo sapiens) discriminate appearance from reality.

    PubMed

    Karg, Katja; Schmelz, Martin; Call, Josep; Tomasello, Michael

    2014-11-01

    Nonhuman great apes and human children were tested for an understanding that appearance does not always correspond to reality. Subjects were 29 great apes (bonobos [Pan paniscus], chimpanzees [Pan troglodytes], gorillas [Gorilla gorilla], and orangutans [Pongo abelii]) and 24 2½-year-old children. In our task, we occluded portions of 1 large and 1 small food stick such that the size relations seemed reversed. Subjects could then choose which one they wanted. There was 1 control condition and 2 experimental conditions (administered within subjects). In the control condition subjects saw only the apparent stick sizes, whereas in the 2 experimental conditions they saw the true stick sizes as well (the difference between them being what the subjects saw first: the apparent or the real stick sizes). All great ape species and children successfully identified the bigger stick, despite its smaller appearance, in the experimental conditions, but not in the control. We discuss these results in relation to the understanding of object permanence and conservation, and exclude reversed reward contingency learning as an explanation. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  18. A comparison of successful and unsuccessful attempts in maximal bench pressing.

    PubMed

    van den Tillaar, Roland; Ettema, Gertjan

    2009-11-01

    This study was designed to compare the differences in EMG and kinematics between successful and unsuccessful attempts in bench pressing at one repetition maximum (1RM) in recreational weight-trained subjects. We hypothesized that failure occurs during the sticking period (the period during which there is a temporary reduction in movement velocity). Eleven male subjects (age = 21.9 +/- 1.8 yr, mass = 80.0 +/- 11.2 kg, height = 1.79 +/- 0.08 m) with at least 1 yr of bench press training experience participated in this study. They performed attempts at 1RM and 1RM + 2.5 kg in bench press during which kinematics and muscle activity were recorded. One successful attempt and one unsuccessful attempt were used for further analysis. Both attempts showed the same sticking period, but only half of the failures occurred during that period. The main differences in the kinematics occurred during the sticking period. Muscle activity, in contrast, showed the same pattern in both attempts and only differed during the downward and the start of the upward movement of the lift. The sticking period occurs in both successful and unsuccessful attempts in maximal bench press. However, failure does not always occur during the sticking period.

  19. A Novel Tactile Sensor with Electromagnetic Induction and Its Application on Stick-Slip Interaction Detection

    PubMed Central

    Liu, Yanjie; Han, Haijun; Liu, Tao; Yi, Jingang; Li, Qingguo; Inoue, Yoshio

    2016-01-01

    Real-time detection of contact states, such as stick-slip interaction between a robot and an object on its end effector, is crucial for the robot to grasp and manipulate the object steadily. This paper presents a novel tactile sensor based on electromagnetic induction and its application on stick-slip interaction. An equivalent cantilever-beam model of the tactile sensor was built and capable of constructing the relationship between the sensor output and the friction applied on the sensor. With the tactile sensor, a new method to detect stick-slip interaction on the contact surface between the object and the sensor is proposed based on the characteristics of friction change. Furthermore, a prototype was developed for a typical application, stable wafer transferring on a wafer transfer robot, by considering the spatial magnetic field distribution and the sensor size according to the requirements of wafer transfer. The experimental results validate the sensing mechanism of the tactile sensor and verify its feasibility of detecting stick-slip on the contact surface between the wafer and the sensor. The sensing mechanism also provides a new approach to detect the contact state on the soft-rigid surface in other robot-environment interaction systems. PMID:27023545

  20. Effect of punch tip geometry and embossment on the punch tip adherence of a model ibuprofen formulation.

    PubMed

    Roberts, Matthew; Ford, James L; MacLeod, Graeme S; Fell, John T; Smith, George W; Rowe, Philip H; Dyas, A Mark

    2004-07-01

    The sticking of a model ibuprofen-lactose formulation with respect to compaction force, punch tip geometry and punch tip embossment was assessed. Compaction was performed at 10, 25 or 40 kN using an instrumented single-punch tablet press. Three sets of 'normal' concave punches were used to evaluate the influence of punch curvature and diameter. The punches were 10, 11 and 12 mm in diameter, respectively. The 10-mm punch was embossed with a letter 'A' logo to assess the influence of an embossment on sticking. Flat-faced punches (12.5 mm) were used for comparison with the concave tooling. Surface profiles (Taylor Hobson Talysurf 120) of the upper punch faces were obtained to evaluate the surface quality of the tooling used. Following compaction, ibuprofen attached to the upper punch face was quantified by spectroscopy. Increasing punch curvature from flat-faced punches to concave decreased sticking. Altering punch diameter of the concave punches had no effect on sticking when expressed as microg mm(-2). The embossed letter 'A' logo increased sticking considerably owing to the probable concentration of shear stresses at the lateral faces of the embossed logo.

  1. Ice Cream Stick Math.

    ERIC Educational Resources Information Center

    Paddock, Cynthia

    1992-01-01

    Described is a teaching technique which uses the collection of ice cream sticks as a means of increasing awareness of quantity in a self-contained elementary special class for students with learning disabilities and mild mental retardation. (DB)

  2. JIGGER STICK USED IN ERECTION. Shown on highline, direction of ...

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

    JIGGER STICK USED IN ERECTION. Shown on highline, direction of view is probably to the north - South Fork Trinity River Bridge, State Highway 299 spanning South Fork Trinity River, Salyer, Trinity County, CA

  3. Green-fuel-mediated synthesis of self-assembled NiO nano-sticks for dual applications—photocatalytic activity on Rose Bengal dye and antimicrobial action on bacterial strains

    NASA Astrophysics Data System (ADS)

    Iyyappa Rajan, P.; Vijaya, J. Judith; Jesudoss, S. K.; Kaviyarasu, K.; Kennedy, L. John; Jothiramalingam, R.; Al-Lohedan, Hamad A.; Vaali-Mohammed, Mansoor-Ali

    2017-08-01

    With aim of promoting the employability of green fuels in the synthesis of nano-scaled materials with new kinds of morphologies for multiple applications, successful synthesis of self-assembled NiO nano-sticks was achieved through a 100% green-fuel-mediated hot-plate combustion reaction. The synthesized NiO nano-sticks show excellent photocatalytic activity on Rose Bengal dye and superior antibacterial potential towards both Gram-positive and Gram-negative bacteria.

  4. A note of effects of kiln stick thickness and air velocity on drying time of southern pine 2 by 4 and 2 by 6 lumber

    Treesearch

    E.W. Price; P. Koch

    1982-01-01

    To dry to 10% moisture content, 4- and 6-inch-wide lumber 1.75 inch thick required about 13.7 h (including 4 3/4-h kiln warmup time) in 5-ft-wide loads at 260 F (wet-bulb temperature was 180 F) on 1.00-inch-thick sticks with air cross-circulated at 1,000 fpm. If air velocity is increased to 1,400 fpm or stick thickness increased to 1.5 inches, kiln time required to...

  5. Design of one-kilometer-long antenna sticks and support structure for a geosynchronous satellite

    NASA Astrophysics Data System (ADS)

    Freeman, Janet Elizabeth

    This study develops a preliminary structural design for three one-kilometer-long antenna sticks and an antenna support structure for a geosynchronous earth-imaging satellite. On each of the antenna sticks is mounted a linear array of over 16,000 antenna elements. The antenna sticks are parallel to each other, and are spaced 1 km apart so that they form the corners of an imaginary triangular tube. This tube is spinning about its long axis. Antenna performance requires that the position of each antenna element be known to an accuracy of 0.5 cm, and that the spacecraft's spin axis be parallel to the earth's spin axis within one degree. Assuming that the position of each joint on each antenna stick is known, the antenna sticks are designed as beams under a uniformly distributed acceleration (due to spacecraft spin) to meet the displacement accuracy requirements for the antenna elements. Both a thin-walled round tube and a three-longeron double-laced truss are considered for the antenna stick structure. A spacecraft spinrate is chosen by considering the effects of environmental torques on the precession of a simplified spacecraft. A preliminary truss-like support structure configuration is chosen, and analyzed in quasi-static equilibrium with control thrusters firing to estimate the axial loads in the structural members. The compressive loads found by this analysis are used to design the support structure members to be buckling-critical three-longeron double-laced truss columns. Some tension-only members consisting of Kevlar cord are included in the design to eliminate the need for bulkier members. The lateral vibration modes of the individual structural members are found by conventional analysis -- the fundamental frequencies are as low as 0.0066 Hz. Finite element dynamic analyses of the structure in free vibration confirm that simplified models of the structure and members can be used to determine the structural modes and natural frequencies for design purposes.

  6. Waffle production: influence of batter ingredients on sticking of fresh egg waffles at baking plates-Part I: effect of starch and sugar components.

    PubMed

    Huber, Regina; Schoenlechner, Regine

    2017-05-01

    Fresh egg waffles are a sweet convenience product typically baked from eggs, water, sugar, flour, fat, leavening agents, emulsifiers, preservatives, and flavors. In industrial production, waffles are baked continuously in high amounts of up to 200 kg raw material per hour. Therefore, it is important that the waffles do not stick onto the baking plates, which can cause significant product loss and increased costs due to interruption of the baking process, required cleaning procedures, and restarting of the energy-consuming start-up phase. Sticking of waffles is greatly influenced not only by baking plate material, release agent, baking temperature, and time, but also by the batter ingredients. In this study, effects of different starches and sugar components were investigated. Within the selected starches, potato starch demonstrated the highest effects on increasing waffle stability and releasing properties compared to wheat and lupine flour (less than 7% sticking waffles). Rice flour performed worst, with almost 50% of sticking waffles. Most of these waffles were broken during take-off, due to their crumbly texture. Within the sugar components, glycerine was better suitable than sorbitol and crystal sugar was superior compared to powdered sugar. They required less take-off force. It could be demonstrated that waffles with increased stability and texture were those that showed the least number of sticking waffles, thus the main aim of batter ingredients was to improve waffle quality. Waffle quality was influenced by batter parameters, significant correlations could be found, for example, a positive correlation between pH- and L-value, negative correlations between pH- and a-value, or density and aw-value. This resulted in significant correlations with take-off-force, which was correlated with L*- and b*-value (negative) and positive to a*-value. Sticking behavior was strongly associated with b*-value (positive) and to a*-value (negative).

  7. Cleaning of nanopillar templates for nanoparticle collection using PDMS

    NASA Astrophysics Data System (ADS)

    Merzsch, S.; Wasisto, H. S.; Waag, A.; Kirsch, I.; Uhde, E.; Salthammer, T.; Peiner, E.

    2011-05-01

    Nanoparticles are easily attracted by surfaces. This sticking behavior makes it difficult to clean contaminated samples. Some complex approaches have already shown efficiencies in the range of 90%. However, a simple and cost efficient method was still missing. A commonly used silicone for soft lithography, PDMS, is able to mold a given surface. This property was used to cover surface-bonded particles from all other sides. After hardening the PDMS, particles are still embedded. A separation of silicone and sample disjoins also the particles from the surface. After this procedure, samples are clean again. This method was first tested with carbon particles on Si surfaces and Si pillar samples with aspect ratios up to 10. Experiments were done using 2 inch wafers, which, however, is not a size limitation for this method.

  8. Interior of Tunnel No. 1356, Stick Pile Tunnel showing timber ...

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

    Interior of Tunnel No. 1356, Stick Pile Tunnel showing timber framing and missing posts, looking northeast. - Western Maryland Railway, Cumberland Extension, Pearre to North Branch, from WM milepost 125 to 160, Pearre, Washington County, MD

  9. 76 FR 62423 - National Institute on Deafness and Other Communication Disorders; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-07

    ...., Rockville, MD 20852, (Telephone Conference Call). Contact Person: Melissa Stick, PhD, MPH, Chief, Scientific...., Rockville, MD 20852, (Telephone Conference Call). Contact Person: Melissa Stick, PhD, MPH, Chief, Scientific...

  10. Effects of stick dynamics on helicopter flying qualities

    NASA Technical Reports Server (NTRS)

    Watson, Douglas C.; Schroeder, Jeffery A.

    1990-01-01

    An experiment that investigated the influence of typical helicopter force-feel system dynamics on roll-axis handling qualities was conducted in concurrent ground and inflight simulations. Variations in lateral control natural frequency and damping ratio, effected by changes in inertia and damping, were evaluated in a disturbance-rejection task. Pilot ratings indicated a preference for low-inertia feel systems, although measured performance was relatively constant over the range of stick characteristics. Force-sensing was compared with position sensing as the input to the control system. Force-sensing improved performance but did not improve pilot ratings. Overall, the results indicated that control-stick dynamics, at least within a reasonable range, did not have a significant effect on pilot-vehicle performance. However, the physical effort required to maintain a desired pilot/manipulator bandwidth became objectionable as the stick inertia increased beyond 5-7 lbm, which was reflected in the pilot ratings and comments.

  11. A complex systems analysis of stick-slip dynamics of a laboratory fault

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Walker, David M.; Tordesillas, Antoinette, E-mail: atordesi@unimelb.edu.au; Small, Michael

    2014-03-15

    We study the stick-slip behavior of a granular bed of photoelastic disks sheared by a rough slider pulled along the surface. Time series of a proxy for granular friction are examined using complex systems methods to characterize the observed stick-slip dynamics of this laboratory fault. Nonlinear surrogate time series methods show that the stick-slip behavior appears more complex than a periodic dynamics description. Phase space embedding methods show that the dynamics can be locally captured within a four to six dimensional subspace. These slider time series also provide an experimental test for recent complex network methods. Phase space networks, constructedmore » by connecting nearby phase space points, proved useful in capturing the key features of the dynamics. In particular, network communities could be associated to slip events and the ranking of small network subgraphs exhibited a heretofore unreported ordering.« less

  12. Constellation Stick Figures Convey Information about Gravity and Neutrinos

    NASA Astrophysics Data System (ADS)

    Mc Leod, David Matthew; Mc Leod, Roger David

    2008-10-01

    12/21/98, at America's Stonehenge, DMM detected, and drew, the full stick-figure equivalent of Canis Major, CM, as depicted by our Wolf Clan leaders, and many others. Profound, foundational physics is implied, since this occurred in the Watch House there, hours before the ``model rose.'' Similar configurations like Orion, Osiris of ancient Egypt, show that such figures are projected through solid parts of the Earth, as two-dimensional equivalents of the three-dimensional star constellations. Such ``sticks'' indicate that ``line equivalents'' connect the stars, and the physical mechanism projects outlines detectable by traditional cultures. We had discussed this ``flashlight'' effect, and recognized some of its implications. RDM states that the flashlight is a strong, distant neutrino source; the lines represent neutrinos longitudinally aligned in gravitational excitation, opaque, to earthbound, transient, transversely excited neutrinos. ``Sticks'' represent ``graviton'' detection. Neutrinos' longitudinal alignment accounts for the weakness of gravitational force.

  13. Light-stick: A problem of marine pollution in Brazil.

    PubMed

    Cesar-Ribeiro, Caio; Rosa, Helena Costi; Rocha, Daniele Oliveira; Dos Reis, Camila Galli Baldini; Prado, Tabata Sarti; Muniz, Daniela Hernandes Coimbra; Carrasco, Raquel; Silva, Flávia Milão; Martinelli-Filho, José Eduardo; Palanch-Hans, Maria Fernanda

    2017-04-15

    Light-sticks are used as bait in surface long-line fishing, to capture swordfish and other large pelagic predators. When discharged in the ocean, it may reach the beaches. The traditional Brazilian community of Costa dos Coqueiros, Bahia, use light-sticks as a medicine for rheumatism, vitiligo and mycoses. It may affect the marine life when its content leak in the open ocean. This work evaluated and identified the acute and chronic toxicity of the light-stick. A high acute toxicity was observed in the mobility/mortality of Artemia sp.; in the fertilization of sea urchin eggs, and a high chronic toxicity in the development of the pluteus larvae of the same sea urchin. The main compounds that probably caused toxicity were the volatiles such as the fluorescent PAH and oxidants such as the hydrogen peroxide. Its disposal in the open ocean is a potential threat for marine life. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. CPW-fed Circularly Polarized Slot Antenna with Small Gap and Stick-shaped Shorted Strip for UHF FRID Readers

    NASA Astrophysics Data System (ADS)

    Pan, Chien-Yuan; Su, Chum-Chieh; Yang, Wei-Lin

    2018-04-01

    A new circularly polarized (CP) slot antenna with a small gap and a stick-shaped shorted strip is presented. The proposed antenna has a sufficient bandwidth for ultrahigh frequency (UHF) radio-frequency identification (RFID) reader applications. The antenna structure consists of a rectangular slot with a small gap, a stick-shaped shorted strip and a 50 Ω coplanar waveguide (CPW) feedline with an asymmetrical ground plane. By using the stick -shaped shorted strip to disturb magnetic current distribution on the slot, the CP radiation can be generated. The measured results demonstrate that the proposed antenna can reach a 10 dB return loss impedance bandwidth of 14.1 % (894-1030 MHz) and a 3 dB axial ratio (AR) bandwidth of 6.4 % (910-970 MHz). The whole antenna size is 80 × 80 × 1.6 mm3.

  15. Simulating stick-slip failure in a sheared granular layer using a physics-based constitutive model

    DOE PAGES

    Lieou, Charles K. C.; Daub, Eric G.; Guyer, Robert A.; ...

    2017-01-14

    In this paper, we model laboratory earthquakes in a biaxial shear apparatus using the Shear-Transformation-Zone (STZ) theory of dense granular flow. The theory is based on the observation that slip events in a granular layer are attributed to grain rearrangement at soft spots called STZs, which can be characterized according to principles of statistical physics. We model lab data on granular shear using STZ theory and document direct connections between the STZ approach and rate-and-state friction. We discuss the stability transition from stable shear to stick-slip failure and show that stick slip is predicted by STZ when the applied shearmore » load exceeds a threshold value that is modulated by elastic stiffness and frictional rheology. Finally, we also show that STZ theory mimics fault zone dilation during the stick phase, consistent with lab observations.« less

  16. Flight Investigation of Control-stick Vibration of the YG-1B Autogiro

    NASA Technical Reports Server (NTRS)

    Bailey, F J , Jr

    1940-01-01

    As a preliminary step in an investigation of control-stick vibration in direct-control autogiros, the periodic variations in the moments transmitted through the control system of a YG-1B autogiro were recorded in flight. The results of the measurements are presented in the form of coefficients of Fourier series expressing the varying part of the lateral and the longitudinal moments acting between rotor and fuselage at the control trunnions. The most important component of the variation in stick force was found to have frequency of three times the rotor speed and an amplitude that rose from negligible values at tip-speed ratio below 0.20 to +/-5.2 pounds longitudinally and +/-3.2 pounds laterally at tip-speed ratios of 0.35. Variations in stick force at all other frequencies were small in comparison with those at three times the rotor speed.

  17. Generation rates and emission factors of particulate matter and particle-bound polycyclic aromatic hydrocarbons of incense sticks.

    PubMed

    Lung, Shih-Chun Candice; Hu, Shu-Chuan

    2003-02-01

    The generation rates and emission factors of particulate matter and associated polycyclic aromatic hydrocarbons (PAHs) from incense burning were assessed in a laboratory setting. The differences among different segments of the same stick, among different sticks of the same kind of incense, and between two kinds of manually made Chih-Chen incense sticks (A and B) were evaluated. Joss sticks were burned inside a 44 cm long elutriator; personal environmental monitors fitted into the top of the elutriator were used to take PM2.5 and PM10 samples of incense smoke. Samples were analyzed for PAHs by gas chromatography-flame ionization Detector. It was found that particle and associated PAHs were generated approximately at 561 microg/min (geometric standard deviation (GSD) = 1.1) and 0.56 microg/min (GSD = 1.1) from Incense A, and at 661 microg/min (GSD = 1.7) and 0.46 microg/min (GSD = 1.3) from Incense B, respectively. One gram of Incense A emitted about 19.8 mg (GSD = 1.1) particulate matter and 17.1 microg (GSD = 1.2) particulate-phase PAHs, while one gram of Incense B produced around 43.6 mg (GSD = 1.1) of particles and 25.2 microg (GSD = 1.2) of particle-bound PAHs. There were significant differences in emissions between Incenses A and B, although they belong to the same class of incense. A 10-20% variability in emissions was observed in the main part of the manually produced stick, and a larger variation was found at both tips of the combustible part.

  18. Reducing pain from palatal needle stick by topical anesthetics: a comparative study between two lidocaine/prilocaine substances.

    PubMed

    Al-Melh, Manal Abu; Andersson, Lars

    2008-01-01

    The aims of this study were to compare the topical anesthetic effect of two different preparations of lidocaine/prilocaine, cream versus thermosetting gel, on the reduction of pain from needle stick in the palate. The study also compared the subjects' preferences with regard to the substances. Two preparations of 2.5% lidocaine/2.5% prilocaine topical anesthetic agents were applied on the palatal mucosa in the canine region bilaterally and blindly to forty subjects. In the same visit, the cream (EMLA) was applied on one side and the thermosetting gel (Oraqix) on the other side, simultaneously. After that, a needle stick was given on each side using a 27-gauge needle inserted to bone contact through the palatal mucosa every second minute during a ten-minute period. Immediately after the needle stick, the subjects started recording their findings using a verbal scale, a visual analogue scale, and a questionnaire form. Significant differences were set at p < 0.05. Both substances reduced or eliminated pain from needle stick in the palate. Significant differences in pain reduction were observed between the two substances. EMLA reduced pain significantly better than Oraqix. With regard to comfort, taste, anesthetic effect, personal preference, and recommendation, the majority of the subjects favored the EMLA cream to the thermosetting gel. No adverse effects were reported by the subjects. Although both topical anesthetic agents are similar in content, the cream seemed to be preferred by the patients and reduced pain from needle stick in the palate significantly better than the thermosetting gel.

  19. Behavior of healthcare workers after injuries from sharp instruments.

    PubMed

    Adib-Hajbaghery, Mohsen; Lotfi, Mohammad Sajjad

    2013-09-01

    Injuries with sharps are common occupational hazards for healthcare workers. Such injuries predispose the staff to dangerous infections such as hepatitis B, C and HIV. The present study was conducted to investigate the behaviors of healthcare workers in Kashan healthcare centers after needle sticks and injuries with sharps in 2012. A cross-sectional study was conducted on 298 healthcare workers of medical centers governed by Kashan University of Medical Sciences. A questionnaire was used in this study. The first part included questions about demographic characteristics. The second part of the questionnaire consisted of 16 items related to the sharp instrument injuries. For data analysis, descriptive and analytical statistics (chi-square, ANOVA and Pearson correlation coefficient) SPSS version 16.0 software was used. From a total of 298 healthcare workers, 114 (38.3%) had a history of injury from needles and sharp instruments in the last six months. Most needle stick and sharp instrument injuries had occurred among the operating room nurses and midwifes; 32.5% of injuries from sharp instruments occurred in the morning shift. Needles were responsible for 46.5% of injuries. The most common actions taken after needle stick injuries were compression (27.2%) and washing the area with soap and water (15.8%). Only 44.6% of the injured personnel pursued follow-up measures after a needle stick or sharp instrument injury. More than a half of the healthcare workers with needle stick or sharp instrument injury had refused follow-up for various reasons. The authorities should implement education programs along with protocols to be implemented after needle stick injuries or sharps.

  20. Healthy Weight: Healthy Weight Loss Starts With a Plan You Can Stick To

    MedlinePlus

    ... Healthy Weight Healthy Weight Loss Starts With a Plan You Can Stick To Past Issues / Summer 2009 ... based on regular physical activity and an eating plan that is balanced, healthy, and easy to follow. ...

  1. 23. HISTORIC VIEW OF ONE STICK REPULSOR OF RAKETENFLUGPLATZ GROUP. ...

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

    23. HISTORIC VIEW OF ONE STICK REPULSOR OF RAKETENFLUGPLATZ GROUP. POSSIBLY 1931, THE STAND IS FOR LAUNCHING NOT FOR STATIC TESTS. - Marshall Space Flight Center, Redstone Rocket (Missile) Test Stand, Dodd Road, Huntsville, Madison County, AL

  2. Validating electromagnetic walking stick rail surface crack measuring systems : final report.

    DOT National Transportation Integrated Search

    2016-06-01

    A series of field studies were undertaken to evaluate electromagnetic walking stick systems and their ability to measure the depth : of damage from surface breaking cracks. In total, four railroads, and four suppliers participated in the project. The...

  3. 1. VIEW OF EAST FRONT OF BREAKER, WITH SCALE STICK, ...

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

    1. VIEW OF EAST FRONT OF BREAKER, WITH SCALE STICK, SHOWING FOUNDATIONS OF RETAIL SCALES IN FOREGROUND, LOOKING WEST - Marvine Colliery, Breaker No. 2, West side Boulevard Avenue, between East Parker Street & Route 380, Scranton, Lackawanna County, PA

  4. Nonneutral plasma diagnostic commissioning for the ALPHA Antihydrogen experiment

    NASA Astrophysics Data System (ADS)

    Konewko, S.; Friesen, T.; Tharp, T. D.; Alpha Collaboration

    2017-10-01

    The ALPHA experiment at CERN creates antihydrogen by mixing antiproton and positron plasmas. Diagnostic measurements of the precursor plasmas are performed using a diagnostic suite, colloquially known as the ``stick.'' This stick has a variety of sensors and is able to move to various heights to align the desired diagnostic with the beamline. A cylindrical electrode, a faraday cup, an electron gun, and a microchannel-plate detector (MCP) are regularly used to control and diagnose plasmas in ALPHA. We have designed, built, and tested a new, upgraded stick which includes measurement capabilities in both beamline directions.

  5. The physics of a popsicle stick bomb

    NASA Astrophysics Data System (ADS)

    Sautel, Jérémy; Bourges, Andréane; Caussarieu, Aude; Plihon, Nicolas; Taberlet, Nicolas

    2017-10-01

    Popsicle sticks can be interlocked in the so-called "cobra weave" to form a chain under tension. When one end of the chain is released, the sticks rapidly disentangle, forming a traveling wave that propagates down the chain. In this paper, the properties of the traveling front are studied experimentally, and classical results from the theory of elasticity allow for a dimensional analysis of the height and speed of the traveling wave. The study presented here can help undergraduate students familiarize themselves with experimental techniques of image processing, and it also demonstrates the power of dimensional analysis and scaling laws.

  6. [Evaluation of olfaction in healthy subjects using the Sniffing Sticks battery].

    PubMed

    Hudson, Lorena; Silva, M Consuelo; Núñez, Juan Cristóbal; Gómez, Rodrigo; Venegas-Francke, Pablo

    2012-04-01

    Olfaction dysfunction is linked to neurodegenerative diseases, therefore the evaluation of this function is becoming important To evaluate olfaction in healthy participants. We evaluated 44 healthy males and 55 females, aged 21 to 89 years with the Sniffing Sticks battery to determine normal values in Chilean population. During the test, participants must correctly identify 12 different odors. Normal olfaction, hyposmia and anosmia were defined. An age related decline in olfaction was observed, especially among males aged 59 years or more. This study provides age and gender specific normal values for the Sniffing Sticks battery.

  7. The use of wooden sticks to assess stream ecosystem functioning: comparison with leaf breakdown rates.

    PubMed

    Arroita, Maite; Aristi, Ibon; Flores, Lorea; Larrañaga, Aitor; Díez, Joserra; Mora, Juanita; Romaní, Anna M; Elosegi, Arturo

    2012-12-01

    Breakdown of organic matter is a key process in streams and rivers, and thus, it has potential to assess functional impairment of river ecosystems. Because the litter-bag method commonly used to measure leaf breakdown is time consuming and expensive, several authors proposed to measure breakdown of wooden sticks instead. Nevertheless, currently there is little information on the performance of wooden sticks versus that of leaves. We compared the breakdown of tongue depressors made of untreated poplar wood, to that of six common leaf species in two large streams in the Basque Country (northern Spain), one polluted and the other unpolluted. Breakdown rates ranged from 0.0011 to 0.0120 day(-1), and were significantly lower in the polluted stream. Wooden sticks performed very similarly to leaves, but were less affected by flood-induced physical abrasion. The ranking of the materials according to their breakdown rate was consistent, irrespective of the stream. The experiments with leaves were 10 times more costly for breakdown rate, 4 times if we include the rest of the variables measured. Therefore wooden sticks offer a promising tool to assess river ecosystem functioning, although more research is necessary to define the thresholds for ecosystem functional impairment. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Double-well dynamics of noise-driven control activation in human intermittent control: the case of stick balancing.

    PubMed

    Zgonnikov, Arkady; Lubashevsky, Ihor

    2015-11-01

    When facing a task of balancing a dynamic system near an unstable equilibrium, humans often adopt intermittent control strategy: Instead of continuously controlling the system, they repeatedly switch the control on and off. Paradigmatic example of such a task is stick balancing. Despite the simplicity of the task itself, the complexity of human intermittent control dynamics in stick balancing still puzzles researchers in motor control. Here we attempt to model one of the key mechanisms of human intermittent control, control activation, using as an example the task of overdamped stick balancing. In doing so, we focus on the concept of noise-driven activation, a more general alternative to the conventional threshold-driven activation. We describe control activation as a random walk in an energy potential, which changes in response to the state of the controlled system. By way of numerical simulations, we show that the developed model captures the core properties of human control activation observed previously in the experiments on overdamped stick balancing. Our results demonstrate that the double-well potential model provides tractable mathematical description of human control activation at least in the considered task and suggest that the adopted approach can potentially aid in understanding human intermittent control in more complex processes.

  9. Extended version of the "Sniffin' Sticks" identification test: test-retest reliability and validity.

    PubMed

    Sorokowska, A; Albrecht, E; Haehner, A; Hummel, T

    2015-03-30

    The extended, 32-item version of the Sniffin' Sticks identification test was developed in order to create a precise tool enabling repeated, longitudinal testing of individual olfactory subfunctions. Odors of the previous test version had to be changed for technical reasons, and the odor identification test needed re-investigation in terms of reliability, validity, and normative values. In our study we investigated olfactory abilities of a group of 100 patients with olfactory dysfunction and 100 controls. We reconfirmed the high test-retest reliability of the extended version of the Sniffin' Sticks identification test and high correlations between the new and the original part of this tool. In addition, we confirmed the validity of the test as it discriminated clearly between controls and patients with olfactory loss. The additional set of 16 odor identification sticks can be either included in the current olfactory test, thus creating a more detailed diagnosis tool, or it can be used separately, enabling to follow olfactory function over time. Additionally, the normative values presented in our paper might provide useful guidelines for interpretation of the extended identification test results. The revised version of the Sniffin' Sticks 32-item odor identification test is a reliable and valid tool for the assessment of olfactory function. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Energy Efficiency Building Code for Commercial Buildings in Sri Lanka

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Busch, John; Greenberg, Steve; Rubinstein, Francis

    2000-09-30

    1.1.1 To encourage energy efficient design or retrofit of commercial buildings so that they may be constructed, operated, and maintained in a manner that reduces the use of energy without constraining the building function, the comfort, health, or the productivity of the occupants and with appropriate regard for economic considerations. 1.1.2 To provide criterion and minimum standards for energy efficiency in the design or retrofit of commercial buildings and provide methods for determining compliance with them. 1.1.3 To encourage energy efficient designs that exceed these criterion and minimum standards.

  11. Effect of stress perturbation on frictional instability: an experimental study

    NASA Astrophysics Data System (ADS)

    Yuanmin, H.; Shengli, M.

    2017-12-01

    We have performed a series of frictional experiments with direct shear configuration of three granite blocks by using a servo-controlled biaxial loading machine. In the experiments, a small- amplitude sine wave is modulated to shear and normal loading in order to study the effects of stress perturbation on stick-slip instability. The main results are as follows. Under the constant average normal stress and the constant loading point velocity in shear direction, the sample shows regular stick-slip behavior. After the stress perturbation is modulated, the correlation between the timing of stick-slip events and the perturbation increases with increasing the perturbation amplitude, and stress drop and interval time of stick-slip events tend to be discrete. This results imply that the change in Coulomb stress caused by stress perturbation may obviously change not only the occurrence time of earthquakes but also the earthquake magnitude. Both shear and normal stress perturbation can affect the stick-slip behavior, shear stress perturbation can only change the driving stress along fault, while the normal stress perturbation can change the contact state of asperities on the fault, so it's effect is more obviously. The stress perturbation can obviously affect acoustic emission (AE) activity during fault friction, which can trigger some AE events so that AE activity before stick-slip becomes stronger and occurs earlier. The perturbation in shear stress is more evident than that in normal stress in affecting AE activity, so we should not only pay attention to the magnitude of Coulomb stress changes caused by the perturbation, but also try to distinguish the stress changes are the shear stress changes or the normal stress changes, when study the effect of stress perturbation on fault friction.

  12. Pediatric and young adult exposure to chemiluminescent glow sticks.

    PubMed

    Hoffman, Robert J; Nelson, Lewis S; Hoffman, Robert S

    2002-09-01

    Although chemiluminescent plastic rods, commonly called "glow sticks" or "light sticks," are typically considered to be minimally toxic or nontoxic, published data about exposure to these products are scarce. To test our hypothesis that exposure to chemiluminescent products is unlikely to result in significant morbidity or mortality and to describe factors associated with exposure by reviewing reports to our urban poison control center of human exposure to chemiluminescent products. Pediatric and young adult exposure to chemiluminescent products reported between January 1, 2000, and April 1, 2001, to our poison control center were evaluated with regard to demographic group, type of product involved, circumstances of exposure, symptoms, and management. Reported routes of exposure (n = 118) included ingestion (n = 108), ocular (n = 9), and dermal exposure (n = 1). Only patients exposed to chemiluminescent fluid from a leaking container reported symptoms (n = 27). Symptoms were limited to transient irritation of the exposure site, and no systemic toxicity occurred. All adults (n = 4) inadvertently ruptured or swallowed intact light sticks while at a dance club or dance party. Most exposure and all adult exposure occurred on holidays or weekends. Most incidences of exposure to chemiluminescent products involve asymptomatic ingestion of fluid that leaks from glow sticks or ingestion of an intact glow stick. Symptoms occur after exposure to chemiluminescent fluid and consist of transient irritation at the site of exposure. The clustering of reported exposure on weekends and in dance clubs and parties coupled with a lack of occupational or workplace exposure suggest that recreational use is a major contributory factor. Exposure to chemiluminescent products infrequently resulted in symptoms and the symptoms reported were minor. Exposure to chemiluminescent products as described is unlikely to cause significant morbidity or mortality.

  13. Single-stick tunneled central venous access using the jugular veins in infants weighing less than 5 kg.

    PubMed

    Lindquester, Will S; Hawkins, C Matthew; Monroe, Eric J; Gill, Anne E; Shivaram, Giridhar M; Seidel, F Glen; Lungren, Matthew P

    2017-11-01

    Despite the demonstrated feasibility of the single-stick technique in the femoral vein, its use in neonates and infants for placing central lines in internal and external jugular veins has not been reported. Describe and assess the safety and efficacy of tunneled jugular central venous catheter placement performed under ultrasound (US) and fluoroscopic guidance in neonates and infants weighing <5 kg using the single-stick technique at three tertiary pediatric hospitals. Thirty-three children weighing less than 5 kg received tunneled central venous access in either internal or external jugular veins using the single-stick technique. Patient history, procedural records and clinical follow-up documents were retrospectively reviewed. Complication rates were compared to those of 41 patients receiving single-stick femoral central lines. Technical complications occurred during one (3.0%) jugular placement with the patient having a failed right-side attempt with subsequent successful left-side placement. The catheters did not last the entire course of treatment in three (9.1%) patients with jugular lines. One patient had the catheter removed due to concern for infection, one catheter was accidentally removed during dressing changes, and one catheter was displaced and subsequently exchanged. Of patients receiving femoral central lines, 1 (2.4%) had a technical complication and 5 catheters (12.2%) did not last the entire course of treatment. The placement of tunneled central venous catheters in neonates/infants <5 kg is safe and technically feasible using the internal/external jugular vein via the single-stick technique. By theoretically reducing the risks of catheter infection by avoiding the diaper area and thrombosis by using larger veins, it may be preferable in certain patient populations.

  14. Short stick exercises for fall prevention among older adults: a cluster randomized trial.

    PubMed

    Yokoi, Katsushi; Yoshimasu, Kouichi; Takemura, Shigeki; Fukumoto, Jin; Kurasawa, Shigeki; Miyashita, Kazuhisa

    2015-01-01

    To investigate the effects of short stick exercise (SSEs) on fall prevention and improvement of physical function in older adults. A cluster randomized trial was conducted in five residential care facilities. The intervention group (n = 51) practiced SSEs for six months, followed by routine care for six more months. The control group (n = 54) received ordinary care for 12 months. The primary outcome measure was the number of fallers, taking into account the time to first fall using the Kaplan-Meier method. The secondary outcome measures were physical and mental functions. The number of fallers was significantly lower in the intervention group (n = 6) than in the control group (n = 16) during the 12 months. The adjusted hazard ratio for a first fall in the intervention group compared with the control group was 0.15 (CI, 0.03 to 0.74, p = 0.02). The fall-free period was significantly longer in the intervention group than in controls (mean ± SD, 10.1 ± 3.0 versus 9.0 ± 4.1 months, p = 0.027). The functional reach and sit and reach tests were significantly improved at three and six months. The SSEs appeared effective for fall prevention and improvement of physical function in older adults. Implications for Rehabilitation The newly developed short stick exercises appear an effective means of reducing falls among older adults in residential care facilities. The short stick exercises seem to have an immediate effect on improving physical functions. Effects gained by performing the short stick exercises, such as static balance, flexibility and agility may last for six months. The short stick exercises were found to be easy for older adults to practice continuously in residential care facilities.

  15. The hockey-stick method to estimate evening dim light melatonin onset (DLMO) in humans.

    PubMed

    Danilenko, Konstantin V; Verevkin, Evgeniy G; Antyufeev, Viktor S; Wirz-Justice, Anna; Cajochen, Christian

    2014-04-01

    The onset of melatonin secretion in the evening is the most reliable and most widely used index of circadian timing in humans. Saliva (or plasma) is usually sampled every 0.5-1 hours under dim-light conditions in the evening 5-6 hours before usual bedtime to assess the dim-light melatonin onset (DLMO). For many years, attempts have been made to find a reliable objective determination of melatonin onset time either by fixed or dynamic threshold approaches. The here-developed hockey-stick algorithm, used as an interactive computer-based approach, fits the evening melatonin profile by a piecewise linear-parabolic function represented as a straight line switching to the branch of a parabola. The switch point is considered to reliably estimate melatonin rise time. We applied the hockey-stick method to 109 half-hourly melatonin profiles to assess the DLMOs and compared these estimates to visual ratings from three experts in the field. The DLMOs of 103 profiles were considered to be clearly quantifiable. The hockey-stick DLMO estimates were on average 4 minutes earlier than the experts' estimates, with a range of -27 to +13 minutes; in 47% of the cases the difference fell within ±5 minutes, in 98% within -20 to +13 minutes. The raters' and hockey-stick estimates showed poor accordance with DLMOs defined by threshold methods. Thus, the hockey-stick algorithm is a reliable objective method to estimate melatonin rise time, which does not depend on a threshold value and is free from errors arising from differences in subjective circadian phase estimates. The method is available as a computerized program that can be easily used in research settings and clinical practice either for salivary or plasma melatonin values.

  16. Effect of Trap Color, Height, and Orientation on the Capture of Yellow and Stick Tea Thrips (Thysanoptera: Thripidae) and Nontarget Insects in Tea Gardens.

    PubMed

    Bian, L; Yang, P X; Yao, Y J; Luo, Z X; Cai, X M; Chen, Z M

    2016-02-03

    Two thrips species-the yellow tea thrips (Scirtothrips dorsalis Hood) and the stick tea thrips (Dendrothrips minowai Priesner)-are serious pests affecting tea plants in southern China. Although the stick tea thrips is primarily restricted to southern China, the yellow tea thrips is gradually proliferating worldwide. Colored sticky card traps may be useful for monitoring and capturing these species, but a systematic analysis has not been conducted to identify the most effective trap color, height, and orientation. We performed indoor experiments using an orthogonal experimental design, as well as field tests in tea gardens, to identify the color most attractive to the two thrips species. Field tests were then conducted using color-optimized traps-lawngreen (RGB: 124, 252, 0) for yellow thrips and lime (RGB: 0, 255, 0) for stick tea thrips-to determine the most effective trap height and orientation. The greatest numbers of both yellow and stick tea thrips were captured on traps positioned 0-20 cm above the tea canopy in an east-west orientation. We also evaluated the performance of the color-optimized sticky card traps compared with commercially available yellow ones. Significantly more yellow and stick tea thrips and fewer natural enemies were captured on the color-optimized traps than on commercial ones. Although additional research is needed to explain the responses of the two different species and to increase trap effectiveness, our findings should assist in the control of these harmful insects. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Stick-slip as a monitor of rates, states and frictional properties along thrusts in sand wedges

    NASA Astrophysics Data System (ADS)

    Rosenau, Matthias; Santimano, Tasca; Ritter, Malte; Oncken, Onno

    2014-05-01

    We developed a sandbox setup which allows monitoring the push of the moving backwall indenting a layer of sand. Depending on the ratio between indenter compliancy versus strain weakening of the granular material, wedge deformation shows unstable slip marked by force drops of various sizes and at multiple temporal scales. Basically we observe long-period slip instabilities related to strain localization during the formation of new thrusts, intermediate-period slip instabilities related to reactivation of existing thrusts and short-period slip instabilities related to the stick-slip mechanism of slip accumulation along "seismic" faults. Observed stick-slip is characterized by highly correlated size and frequency ("regular stick-slip") and is sensitive to integrated normal load, slip rate and frictional properties along the active thrust(s). By independently constraining the frictional properties using a ring-shear tester, we infer the integrated normal loads on the active faults from the stick-slip events and benchmark the results against a model calculating the normal loads from the wedge geometry. This way we are able to monitor rates, states and frictional properties along thrusts in sand wedges at unprecedented detail. As an example of application, a kinematic analysis of the stick slip events in the sandbox demonstrates how slip rates along thrusts vary systematically within accretion cycles although the kinematic boundary condition is stationary. Accordingly transient fault slip rates may accelerate up to twice the long-term convergence rate during formation of new thrusts and decelerate in the post-thrust formation stage in a non-linear way. Applied to nature this suggests that fault slip rate variations at the thousand-year time scale might be attributable to the elasticity of plates and material weakening rather than changes in plate velocities.

  18. On the Minimum Induced Drag of Wings

    NASA Technical Reports Server (NTRS)

    Bowers, Albion H.

    2015-01-01

    Birds do not require the use of vertical tails. They do not appear to have any mechanism by which to control their yaw. As an example the albatross is notable in this regard. The authors believe this is possible because of a unique adaptation by which there exists a triple-optimal solution that provides the maximum aerodynamic efficiency, the minimum structural weight, and it provides for coordination of control in roll and yaw. Until now, this solution has eluded researchers, and remained unknown. Here it is shown that the correct specification of spanload provides for all three solutions at once, maximum aerodynamic efficiency, minimum structural weight, and coordinated control. The implications of this result has far reaching effects on the design of aircraft, as well as dramatic efficiency improvement.

  19. Curiosity & Connections

    ERIC Educational Resources Information Center

    Lim, Kien H.

    2014-01-01

    Retaining mathematical knowledge is difficult for many students, especially for those who learn facts and procedures without understanding the meanings underlying the symbols and operations. Repeated practice may be necessary for developing skills but is unlikely to make conceptual ideas stick. An idea is more likely to stick if students are…

  20. The Vernier Caliper and Significant Figures.

    ERIC Educational Resources Information Center

    Oberhofer, E. S.

    1985-01-01

    Misconceptions occur because the caliper is often read with the same significant figures as a meter stick; however, the precision of the vernier caliper is greater than the precision of a meter stick. Clarification of scale reading, precision of both tools, and significant figures are discussed. (JN)

  1. Paint-Stirrer Submarine

    ERIC Educational Resources Information Center

    Young, Jocelyn; Hardy, Kevin

    2007-01-01

    In this article, the authors discuss a unique and challenging laboratory exercise called, the paint-stir-stick submarine, that keeps the students enthralled. The paint-stir-stick submarine fits beautifully with the National Science Education Standards Physical Science Content Standard B, and with the California state science standards for physical…

  2. Hardwood log grading scale stick improved

    Treesearch

    M. D. Ostrander; G. H. Englerth

    1953-01-01

    In February 1952 the Northeastern Forest Experiment Station described ( Research Note 13) a new log-grading scale stick developed by the Station for use as a visual aid in grading hardwood factory logs. It was based on the U. S. Forest Products Laboratory's log-grade specifications.

  3. Stick-slip friction and ageing in Velcro®

    NASA Astrophysics Data System (ADS)

    Mariani, Lisa; Angiolillo, Paul

    2014-03-01

    The mesoscopic hook and loop system of Velcro® provides a model of stick-slip friction that exhibits behavior reminiscent of results seen in nanoscale model systems. The friction is linearly dependent on contact area and independent of driving velocity. Morever, there is a power law dependence of the friction on loading, with exponent between 1/4 and 1/3. Furthermore, the evolution of stick-slip to more smooth sliding, as controlled by contact area, is also noted. These transition predictions follow power law profiles, as well, with respect to increasing contact area. Thus, the hook-and-loop system shows to be a good mesoscale model system of stick-slip friction and provides a link between nanoscale and macroscale friction. Through an investigation into the ageing of the hooks in the system, the data suggests that the hooks age during the shearing regime and take a characteristic time to return to initial attachment strength. Additionally, there does not appear to be a significant affect of ageing on the kinetic friction experienced by the system.

  4. Modified carbon fibers to improve composite properties. [sizing fibers for reduced electrical conductivity and adhesion during combustion

    NASA Technical Reports Server (NTRS)

    Shepler, R. E.

    1979-01-01

    Thin coatings, 5 to 10 wt. percent, were applied to PAN-based carbon fibers. These coatings were intended to make the carbon fibers less electrically conductive or to cause fibers to stick together when a carbon fiber/epoxy composite burned. The effectiveness of the coatings in these regards was evaluated in burn tests with a test rig designed to simulate burning, impact and wind conditions which might release carbon fibers. The effect of the coatings on fiber and composite properties and handling was also investigated. Attempts at sizing carbon fibers with silicon dioxide, silicon carbide and boron nitride meet with varying degrees of success; however, none of these materials provided an electrically nonconductive coating. Coatings intended to stick carbon fibers together after a composite burned were sodium silicate, silica gel, ethyl silicate, boric acid and ammonium borate. Of these, only the sodium silicate and silica gel provided any sticking together of fibers. The amount of sticking was insufficient to achieve the desired objectives.

  5. Understanding and controlling regime switching in molecular diffusion

    NASA Astrophysics Data System (ADS)

    Hallerberg, S.; de Wijn, A. S.

    2014-12-01

    Diffusion can be strongly affected by ballistic flights (long jumps) as well as long-lived sticking trajectories (long sticks). Using statistical inference techniques in the spirit of Granger causality, we investigate the appearance of long jumps and sticks in molecular-dynamics simulations of diffusion in a prototype system, a benzene molecule on a graphite substrate. We find that specific fluctuations in certain, but not all, internal degrees of freedom of the molecule can be linked to either long jumps or sticks. Furthermore, by changing the prevalence of these predictors with an outside influence, the diffusion of the molecule can be controlled. The approach presented in this proof of concept study is very generic and can be applied to larger and more complex molecules. Additionally, the predictor variables can be chosen in a general way so as to be accessible in experiments, making the method feasible for control of diffusion in applications. Our results also demonstrate that data-mining techniques can be used to investigate the phase-space structure of high-dimensional nonlinear dynamical systems.

  6. Using glow stick chemistry for biological imaging.

    PubMed

    Tseng, Jen-Chieh; Bailey, Dyane; Tupper, Tanya; Kung, Andrew L

    2014-08-01

    This study describes an imaging strategy based on glow stick chemistry to non-invasively image oxidative stress and reactive oxygen species (ROS) production in living animals. Upon stimulation, phagocytes produce toxic levels of ROS to kill engulfed microorganisms. The mitochondrial respiratory chain continually generates low levels of superoxide (O2·(-)) that serve as a source for generation of downstream ROS, which function as regulatory signaling intermediaries. A ROS-reacting substrate, 2-methyl-6-[4-methoxyphenyl]-3,7-dihydroimidazo[1,2-a]pyrazin-3-one hydrochloride, was used as the chemical energy donor for generating energy transfer luminescence in phagosomes and mitochondria. Using targeted photoluminescent dyes with specific subcellular localization that serve as chemical energy recipients, our imaging data demonstrate proof-of-concept for using glow stick chemistry to visualize ROS production associated with phagocytosis and mitochondrial respiration in living mice. Glow stick imaging is a complementary hybrid of chemiluminescence and photoluminescence imaging, capable of generating red or far-red emission for deep tissue imaging.

  7. Waffle production: influence of batter ingredients on sticking of waffles at baking plates-Part II: effect of fat, leavening agent, and water.

    PubMed

    Huber, Regina; Schoenlechner, Regine

    2017-05-01

    Fresh egg waffles are continuously baked in tunnel baking ovens in industrial scale. Waffles that partly or fully stick to the baking plates cause significant product loss and increased costs. The aim of this study was, therefore, to investigate the effect of different recipe ingredients on the sticking behavior of waffles. In this second part, ingredients investigated were different leavening agents (sodium acid pyrophosphate, ammonium bicarbonate, magnesium hydroxide carbonate, or monocalcium phosphate), different fat sources (rapeseed oil, cocos fat, butter, or margarine), and different water sources (tap water 12°dH and distilled water). Within the different types of fats, solid fats with high amount of short-chain fatty acids (cocos fat or butter) decreased the number of sticking waffles compared to liquid oils (rapeseed oil). Regarding leavening agents, magnesium hydroxide carbonate and ammonium bicarbonate were superior to sodium acid pyrophosphate or monocalcium phosphate. Between the two water sources, effects were small.

  8. Heat transfer with hockey-stick steam generator. [LMFBR

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moody, E; Gabler, M J

    1977-11-01

    The hockey-stick modular design concept is a good answer to future needs for reliable, economic LMFBR steam generators. The concept was successfully demonstrated in the 30 Mwt MSG test unit; scaled up versions are currently in fabrication for CRBRP usage, and further scaling has been accomplished for PLBR applications. Design and performance characteristics are presented for the three generations of hockey-stick steam generators. The key features of the design are presented based on extensive analytical effort backed up by extensive ancillary test data. The bases for and actual performance evaluations are presented with emphasis on the CRBRP design. The designmore » effort on these units has resulted in the development of analytical techniques that are directly applicable to steam generators for any LMFBR application. In conclusion, the hockey-stick steam generator concept has been proven to perform both thermally and hydraulically as predicted. The heat transfer characteristics are well defined, and proven analytical techniques are available as are personnel experienced in their use.« less

  9. Observations of premonitory acoustic emission and slip nucleation during a stick slip experiment in smooth faulted Westerly granite

    USGS Publications Warehouse

    Thompson, B.D.; Young, R.P.; Lockner, D.A.

    2005-01-01

    To investigate laboratory earthquakes, stick-slip events were induced on a saw-cut Westerly granite sample by triaxial loading at 150 MPa confining pressure. Acoustic emissions (AE) were monitored using an innovative continuous waveform recorder. The first motion of each stick slip was recorded as a large-amplitude AE signal. These events source locate onto the saw-cut fault plane, implying that they represent the nucleation sites of the dynamic failure stick-slip events. The precise location of nucleation varied between events and was probably controlled by heterogeneity of stress or surface conditions on the fault. The initial nucleation diameter of each dynamic instability was inferred to be less than 3 mm. A small number of AE were recorded prior to each macro slip event. For the second and third slip events, premonitory AE source mechanisms mimic the large scale fault plane geometry. Copyright 2005 by the American Geophysical Union.

  10. Spatio-temporal foreshock activity during stick-slip experiments of large rock samples

    NASA Astrophysics Data System (ADS)

    Tsujimura, Y.; Kawakata, H.; Fukuyama, E.; Yamashita, F.; Xu, S.; Mizoguchi, K.; Takizawa, S.; Hirano, S.

    2016-12-01

    Foreshock activity has sometimes been reported for large earthquakes, and has been roughly classified into the following two classes. For shallow intraplate earthquakes, foreshocks occurred in the vicinity of the mainshock hypocenter (e.g., Doi and Kawakata, 2012; 2013). And for intraplate subduction earthquakes, foreshock hypocenters migrated toward the mainshock hypocenter (Kato, et al., 2012; Yagi et al., 2014). To understand how foreshocks occur, it is useful to investigate the spatio-temporal activities of foreshocks in the laboratory experiments under controlled conditions. We have conducted stick-slip experiments by using a large-scale biaxial friction apparatus at NIED in Japan (e.g., Fukuyama et al., 2014). Our previous results showed that stick-slip events repeatedly occurred in a run, but only those later events were preceded by foreshocks. Kawakata et al. (2014) inferred that the gouge generated during the run was an important key for foreshock occurrence. In this study, we proceeded to carry out stick-slip experiments of large rock samples whose interface (fault plane) is 1.5 meter long and 0.5 meter wide. After some runs to generate fault gouge between the interface. In the current experiments, we investigated spatio-temporal activities of foreshocks. We detected foreshocks from waveform records of 3D array of piezo-electric sensors. Our new results showed that more than three foreshocks (typically about twenty) had occurred during each stick-slip event, in contrast to the few foreshocks observed during previous experiments without pre-existing gouge. Next, we estimated the hypocenter locations of the stick-slip events, and found that they were located near the opposite end to the loading point. In addition, we observed a migration of foreshock hypocenters toward the hypocenter of each stick-slip event. This suggests that the foreshock activity observed in our current experiments was similar to that for the interplate earthquakes in terms of the spatio-temporal pattern. This work was supported by NIED research project "Development of monitoring and forecasting technology for crustal activity", JSPS KAKENHI Grant Number 23340131, and MEXT of Japan, under its Earthquake and Volcano Hazards Observation and Research Program.

  11. The Effects of Elevator Rate Limiting and Stick Dynamics on Longitudinal Pilot-Induced Oscillations

    DTIC Science & Technology

    1997-03-01

    systems) were modeled as follows: 1 _ 0.1251Ks in / lb Fe, [0.6 K, , 26 K,] The equation is written in shorthand notation where: [,co] = (S2 + 2 o(s + con2... equation : (5,. , 0.125/K , in / lb Fe [0.6K,, 26K,,] where [c0n] (S2 + 2 (ons + (0n2) (a)= (s + a) The nominal stick, feel system 1, had a damping...System Description The HAVE GRIP stick dynamics (feel system) were modeled by the following equation : _es_ O.12 5 K s in / lb Fes [0.6, 26K j,] The

  12. Energy-efficient algorithm for broadcasting in ad hoc wireless sensor networks.

    PubMed

    Xiong, Naixue; Huang, Xingbo; Cheng, Hongju; Wan, Zheng

    2013-04-12

    Broadcasting is a common and basic operation used to support various network protocols in wireless networks. To achieve energy-efficient broadcasting is especially important for ad hoc wireless sensor networks because sensors are generally powered by batteries with limited lifetimes. Energy consumption for broadcast operations can be reduced by minimizing the number of relay nodes based on the observation that data transmission processes consume more energy than data reception processes in the sensor nodes, and how to improve the network lifetime is always an interesting issue in sensor network research. The minimum-energy broadcast problem is then equivalent to the problem of finding the minimum Connected Dominating Set (CDS) for a connected graph that is proved NP-complete. In this paper, we introduce an Efficient Minimum CDS algorithm (EMCDS) with help of a proposed ordered sequence list. EMCDS does not concern itself with node energy and broadcast operations might fail if relay nodes are out of energy. Next we have proposed a Minimum Energy-consumption Broadcast Scheme (MEBS) with a modified version of EMCDS, and aimed at providing an efficient scheduling scheme with maximized network lifetime. The simulation results show that the proposed EMCDS algorithm can find smaller CDS compared with related works, and the MEBS can help to increase the network lifetime by efficiently balancing energy among nodes in the networks.

  13. 40 CFR Appendix B to Part 50 - Reference Method for the Determination of Suspended Particulate Matter in the Atmosphere (High...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... filters used are specified to have a minimum collection efficiency of 99 percent for 0.3 µm (DOP... electronic timers have much better set-point resolution than mechanical timers, but require a battery backup... Collection efficiency: 99 percent minimum as measured by the DOP test (ASTM-2986) for particles of 0.3 µm...

  14. 40 CFR Appendix B to Part 50 - Reference Method for the Determination of Suspended Particulate Matter in the Atmosphere (High...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... filters used are specified to have a minimum collection efficiency of 99 percent for 0.3 µm (DOP... electronic timers have much better set-point resolution than mechanical timers, but require a battery backup... Collection efficiency: 99 percent minimum as measured by the DOP test (ASTM-2986) for particles of 0.3 µm...

  15. A fundamental approach to the sticking of insect residues to aircraft wings

    NASA Technical Reports Server (NTRS)

    Eiss, N. S., Jr.; Wightman, J. P.

    1983-01-01

    The sticking of insect residues to aircraft wings is investigated. The major topics of this review are: Experimentally tested methods, testing techniques, the effect of surface roughness height on aerodynamic drag, materials tested and, the adhesive properties of insect body fluids are reviewed.

  16. 11. VIEW OF STARBOARD ELEVATION OF STERN (WITHOUT SCALE STICK), ...

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

    11. VIEW OF STARBOARD ELEVATION OF STERN (WITHOUT SCALE STICK), SHOWING WHEELHOUSE, DUCKTAIL, AND RUDDER ASSEMBLY; CRANE AT LEFT POSITIONED FOR REMOVAL OF WHEELHOUSE; UNFINISHED FERRO-CONCRETE HULL OF UNKNOWN VESSEL IN BACKGROUND - Bugeye "Louise Travers", Intersection of Routes 2 & 4, Solomons, Calvert County, MD

  17. Electrophoretic Separation of Single Particles Using Nanoscale Thermoplastic Columns.

    PubMed

    Weerakoon-Ratnayake, Kumuditha M; Uba, Franklin I; Oliver-Calixte, Nyoté J; Soper, Steven A

    2016-04-05

    Phenomena associated with microscale electrophoresis separations cannot, in many cases, be applied to the nanoscale. Thus, understanding the electrophoretic characteristics associated with the nanoscale will help formulate relevant strategies that can optimize the performance of separations carried out on columns with at least one dimension below 150 nm. Electric double layer (EDL) overlap, diffusion, and adsorption/desorption properties and/or dielectrophoretic effects giving rise to stick/slip motion are some of the processes that can play a role in determining the efficiency of nanoscale electrophoretic separations. We investigated the performance characteristics of electrophoretic separations carried out in nanoslits fabricated in poly(methyl methacrylate), PMMA, devices. Silver nanoparticles (AgNPs) were used as the model system with tracking of their transport via dark field microscopy and localized surface plasmon resonance. AgNPs capped with citrate groups and the negatively charged PMMA walls (induced by O2 plasma modification of the nanoslit walls) enabled separations that were not apparent when these particles were electrophoresed in microscale columns. The separation of AgNPs based on their size without the need for buffer additives using PMMA nanoslit devices is demonstrated herein. Operational parameters such as the electric field strength, nanoslit dimensions, and buffer composition were evaluated as to their effects on the electrophoretic performance, both in terms of efficiency (plate numbers) and resolution. Electrophoretic separations performed at high electric field strengths (>200 V/cm) resulted in higher plate numbers compared to lower fields due to the absence of stick/slip motion at the higher electric field strengths. Indeed, 60 nm AgNPs could be separated from 100 nm particles in free solution using nanoscale electrophoresis with 100 μm long columns.

  18. Individual and social learning processes involved in the acquisition and generalization of tool use in macaques

    PubMed Central

    Macellini, S.; Maranesi, M.; Bonini, L.; Simone, L.; Rozzi, S.; Ferrari, P. F.; Fogassi, L.

    2012-01-01

    Macaques can efficiently use several tools, but their capacity to discriminate the relevant physical features of a tool and the social factors contributing to their acquisition are still poorly explored. In a series of studies, we investigated macaques' ability to generalize the use of a stick as a tool to new objects having different physical features (study 1), or to new contexts, requiring them to adapt the previously learned motor strategy (study 2). We then assessed whether the observation of a skilled model might facilitate tool-use learning by naive observer monkeys (study 3). Results of study 1 and study 2 showed that monkeys trained to use a tool generalize this ability to tools of different shape and length, and learn to adapt their motor strategy to a new task. Study 3 demonstrated that observing a skilled model increases the observers' manipulations of a stick, thus facilitating the individual discovery of the relevant properties of this object as a tool. These findings support the view that in macaques, the motor system can be modified through tool use and that it has a limited capacity to adjust the learnt motor skills to a new context. Social factors, although important to facilitate the interaction with tools, are not crucial for tool-use learning. PMID:22106424

  19. Sniffin' Sticks and olfactory system imaging in patients with Kallmann syndrome.

    PubMed

    Ottaviano, Giancarlo; Cantone, Elena; D'Errico, Arianna; Salvalaggio, Alessandro; Citton, Valentina; Scarpa, Bruno; Favaro, Angela; Sinisi, Antonio Agostino; Liuzzi, Raffaele; Bonanni, Guglielmo; Di Salle, Francesco; Elefante, Andrea; Manara, Renzo; Staffieri, Alberto; Martini, Alessandro; Brunetti, Arturo

    2015-09-01

    The relationship between olfactory function, rhinencephalon and forebrain changes in Kallmann syndrome (KS) have not been adequately investigated. We evaluated a large cohort of male KS patients using Sniffin' Sticks and MRI in order to study olfactory bulb (OB) volume, olfactory sulcus (OS) depth, cortical thickness close to the OS, and olfactory phenotype. Olfaction was assessed administering Sniffin' Sticks®, in 38 KS patients and 17 controls (by means of Screening 12 test®). All subjects underwent magnetic resonance imaging (MRI) to study OB volume, sulcus depth, and cortical thickness. Compared to controls, KS patients showed smaller OB volume (p<0.0001), reduced sulcus depth (p<0.0001), and thicker cortex in the region close to the OS (p<0.0001). Anosmic KS patients had smaller OB than controls and hyposmic KS patients; there was no difference between hyposmic KS patients and controls. OB volume correlated with Sniffin' Sticks score (r = 0.64; p < 0.001), OS depth (p<0.0001) and, inversely, with cortical thickness changes (p<0.0001). Sniffin' Sticks showed an inverse correlation with cortical thickness (r = -0.5; p<0.0001) and a trend toward a statistically significant correlation with OS depth. The present study provides further evidence of the strict relationship between olfaction and OB volume. The strong correlation between OB volume and the overlying cortical changes highlights the key role of rhinencephalon in forebrain embryogenesis. © 2015 ARS-AAOA, LLC.

  20. Comparative evaluation of the antimicrobial efficacy of four chewing sticks commonly used in South India: an in vitro study.

    PubMed

    Elangovan, Arun; Muranga, Jayanthi; Joseph, Elizabeth

    2012-01-01

    The use of chewing sticks has been well documented since ancient times in India. Chewing sticks are a good alternative to the toothbrush for maintaining oral hygiene. The present study was designed and conducted to compare and evaluate the antimicrobial effects of the aqueous extracts of neem, miswak, mango, and banyan chewing sticks against two bacterial species considered the most important in the initiation and progression of dental caries, namely Streptococcus mutans and Lactobacillus acidophilus, respectively. Twigs of the above mentioned chewing sticks were sun dried and powdered, and sterile aqueous solutions of 10%, 25% and 50% concentrations were prepared. Culture plates for S mutans and L acidophilus were prepared and the growth was transferred to nutrient agar and Mueller-Hinton agar; antimicrobial activity of the extracts was tested after 72 h, using the disc diffusion method. Normal saline was used as control. The antimicrobial activity of neem, miswak, and mango extracts increased as their concentrations increased. Both banyan extract and saline showed no antimicrobial activity against the organisms tested. Based on the zones of inhibition, aqueous extracts of neem showed the most antimicrobial activity against S mutans, while miswak extracts showed superior antimicrobial activity against L acidophilus. We recommend further phytochemical and pharmacological studies to discover newer nonsynthetic tooth pastes and mouthwashes.

  1. The molecular dynamics of adsorption and dissociation of O{sub 2} on Pt(553)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jacobse, Leon, E-mail: l.jacobse@chem.leidenuniv.nl; Dunnen, Angela den; Juurlink, Ludo B. F.

    2015-07-07

    Molecular adsorption and dissociation of O{sub 2} on the stepped Pt(553) surface have been investigated using supersonic molecular beam techniques and temperature programmed desorption. The initial and coverage-dependent sticking probability was determined with the King and Wells technique for various combinations of incident kinetic energy, surface temperature, incident angle, and surface coverage. A comparison with similar data for Pt(533) and Pt(110)(1 × 2) shows quantitatively the same high step-induced sticking at low incident energies compared to Pt(111). The enhancement is therefore insensitive to the exact arrangement of atoms forming surface corrugation. We consider energy transfer and electronic effects to explainmore » the enhanced sticking. On the other hand, dissociation dynamics at higher incident kinetic energies are strongly dependent on step type. The Pt(553) and Pt(533) surfaces are more reactive than Pt(111), but the (100) step shows higher sticking than the (110) step. We relate this difference to a variation in the effective lowering of the barrier to dissociation from molecularly adsorbed states into atomic states. Our findings are in line with results from experimental desorption studies and theoretical studies of atomic binding energies. We discuss the influence of the different step types on sticking and dissociation dynamics with a one-dimensional potential energy surface.« less

  2. Kangaroo care and behavioral and physiologic pain responses in very-low-birth-weight twins: a case study.

    PubMed

    Cong, Xiaomei; Cusson, Regina M; Hussain, Naveed; Zhang, Di; Kelly, Sharon P

    2012-09-01

    The purpose of this case study was to describe pain responses in three study conditions: longer (30 minutes) kangaroo care (KC) before and throughout heel stick (KC30), shorter (15 minutes) KC before and throughout heel stick (KC15), and incubator care throughout heel stick (IC) in 28-week gestational age twins. Pain responses were measured by crying time, Preterm Infant Pain Profile (PIPP), and heart rate variability indexes, including low-frequency power (LF, representing sympathetic activity), high-frequency power (HF, parasympathetic activity), and LF/HF ratio (sympathetic-parasympathetic balance). Both twins cried more and had higher PIPP pain scores and tachycardia during heel stick in the IC condition. Infant B had an incident of apnea and tachycardia by the end of the heel stick and a bradycardia episode during recovery in the IC condition. The twins had lower LF/HF ratios (better autonomic nervous system balance) during recovery in both longer and shorter KC conditions compared with the IC condition. Infant B had difficulty returning to LF/HF ratio baseline level after the painful procedure in the IC condition. These data suggest that both longer and shorter KC before and throughout painful procedures can be helpful in reducing behavioral and physiologic pain responses in preterm infants. Copyright © 2012 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  3. Efficient micromagnetics for magnetic storage devices

    NASA Astrophysics Data System (ADS)

    Escobar Acevedo, Marco Antonio

    Micromagnetics is an important component for advancing the magnetic nanostructures understanding and design. Numerous existing and prospective magnetic devices rely on micromagnetic analysis, these include hard disk drives, magnetic sensors, memories, microwave generators, and magnetic logic. The ability to examine, describe, and predict the magnetic behavior, and macroscopic properties of nanoscale magnetic systems is essential for improving the existing devices, for progressing in their understanding, and for enabling new technologies. This dissertation describes efficient micromagnetic methods as required for magnetic storage analysis. Their performance and accuracy is demonstrated by studying realistic, complex, and relevant micromagnetic system case studies. An efficient methodology for dynamic micromagnetics in large scale simulations is used to study the writing process in a full scale model of a magnetic write head. An efficient scheme, tailored for micromagnetics, to find the minimum energy state on a magnetic system is presented. This scheme can be used to calculate hysteresis loops. An efficient scheme, tailored for micromagnetics, to find the minimum energy path between two stable states on a magnetic system is presented. This minimum energy path is intimately related to the thermal stability.

  4. 50 CFR 660.712 - Longline fishery.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...° long. (7) No light stick may be possessed on board a vessel registered for use of longline gear during... light stick as used in this paragraph is any type of light emitting device, including any flourescent glow bead, chemical, or electrically powered light that is affixed underwater to the longline gear. (8...

  5. 50 CFR 660.712 - Longline fishery.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...° long. (7) No light stick may be possessed on board a vessel registered for use of longline gear during... light stick as used in this paragraph is any type of light emitting device, including any flourescent glow bead, chemical, or electrically powered light that is affixed underwater to the longline gear. (8...

  6. 50 CFR 660.712 - Longline fishery.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...° long. (7) No light stick may be possessed on board a vessel registered for use of longline gear during... light stick as used in this paragraph is any type of light emitting device, including any flourescent glow bead, chemical, or electrically powered light that is affixed underwater to the longline gear. (8...

  7. 50 CFR 660.712 - Longline fishery.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...° long. (7) No light stick may be possessed on board a vessel registered for use of longline gear during... light stick as used in this paragraph is any type of light emitting device, including any flourescent glow bead, chemical, or electrically powered light that is affixed underwater to the longline gear. (8...

  8. Talking Stick. Volume 28, Number 6, July-August 2011

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2011-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/ February, March/April, May/ June, July/August, September/October, and November/ December by the Association of College and University Housing Officers-International. Each issue is divided into three sections, namely: Features, Columns, and Departments. These sections contain…

  9. Talking Stick. Volume 27, Number 3, January-February 2010

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2010-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections: Features, Columns, and Departments. These sections contain articles…

  10. Talking Stick. Volume 29, Number 6, July-August 2012

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2012-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections: Features, Columns, and Departments. These sections contain…

  11. Talking Stick. Volume 29, Number 2, November-December 2011

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2011-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections: Features, Columns, and Departments. These sections contain articles…

  12. Talking Stick. Volume 29, Number 4, March-April 2012

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2012-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections: Features, Columns, and Departments. These sections contain articles…

  13. Talking Stick. Volume 26, Number 6, July-August 2009

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2009-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections: Features, Columns, and Departments. These sections contain articles…

  14. Talking Stick. Volume 27, Number 5, May-June 2010

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2010-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections: Features, Columns, and Departments. These sections contain articles…

  15. Plotting the Analemma from Shadow Stick Observations.

    ERIC Educational Resources Information Center

    Glenn, William H.

    1982-01-01

    Secondary students can study time and the motions of the sun by plotting an analemma, a graphic representation of the declination of the sun and the equation of time for every day of the year. They can collect data by measuring a dowel stick's shadow in the noon sun. (KC)

  16. Talking Stick. Volume 28, Number 5, May-June 2011

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2011-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections, namely: Features, Columns, and Departments. These sections contain…

  17. Talking Stick. Volume 28, Number 4, March-April 2011

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2011-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections, namely: Features, Columns, and Departments. These sections contain…

  18. THE RATES OF POLYCYCLIC AROMATIC HYDROCARBON EMISSIONS FROM INCENSE BURNING

    EPA Science Inventory

    The paper presents the results of experiments performed to determine the amounts of gas- and particle-phase polycyclic aromatic hydrocarbons (PAHS) in incense smoke. Ten brands of incense, 3 of stick, 2 of joss stick, and one each of cone, smudge bundle, rope, powder, and rock, w...

  19. Talking Stick. Volume 27, Number 4, March-April 2010

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2010-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections: Features, Columns, and Departments. These sections contain…

  20. The Philippine "Hip Hop Stick Dance"

    ERIC Educational Resources Information Center

    Lewis, Lisa

    2012-01-01

    This article introduces a dance that blends the traditional cultural heritage of the Philippines with modern music and moves. "Hip Hop Stick Dance" incorporates Tinikling (the Philippine national dance) and Arnis (a Filipino style of martial arts) to create a contemporary combination of rhythm, dance, and fitness. It was designed to introduce…

  1. Talking Stick. Volume 29, Number 3, January-February 2012

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2012-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections: Features, Columns, and Departments. These sections contain articles…

  2. The Mathematics of Sundials

    ERIC Educational Resources Information Center

    Vincent, Jill

    2008-01-01

    As early as 3500 years ago, shadows of sticks were used as a primitive instrument for indicating the passage of time through the day. The stick came to be called a "gnomon" or "one who knows." Early Babylonian obelisks were designed to determine noon. The development of trigonometry by Greek mathematicians meant that hour lines…

  3. Talking Stick. Volume 28, Number 2, November-December 2010

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2010-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections, namely: Features, Columns, and Departments. These sections…

  4. Talking Stick. Volume 27, Number 6, July-August 2010

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2010-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections: Features, Columns, and Departments. These sections contain articles…

  5. Talking Stick. Volume 27, Number 1, September-October 2009

    ERIC Educational Resources Information Center

    Baumann, James A., Ed.

    2009-01-01

    The "Talking Stick" is published bimonthly, six times a year in January/February, March/April, May/June, July/August, September/October, and November/December by the Association of College and University Housing Officers-International. Each issue is divided into three sections: Features, Columns, and Departments. These sections contain…

  6. On the minimum quantum requirement of photosynthesis.

    PubMed

    Zeinalov, Yuzeir

    2009-01-01

    An analysis of the shape of photosynthetic light curves is presented and the existence of the initial non-linear part is shown as a consequence of the operation of the non-cooperative (Kok's) mechanism of oxygen evolution or the effect of dark respiration. The effect of nonlinearity on the quantum efficiency (yield) and quantum requirement is reconsidered. The essential conclusions are: 1) The non-linearity of the light curves cannot be compensated using suspensions of algae or chloroplasts with high (>1.0) optical density or absorbance. 2) The values of the maxima of the quantum efficiency curves or the values of the minima of the quantum requirement curves cannot be used for estimation of the exact value of the maximum quantum efficiency and the minimum quantum requirement. The estimation of the maximum quantum efficiency or the minimum quantum requirement should be performed only after extrapolation of the linear part at higher light intensities of the quantum requirement curves to "0" light intensity.

  7. Influence of movement regime of stick-slip process on the size distribution of accompanying acoustic emission characteristics

    NASA Astrophysics Data System (ADS)

    Matcharashvili, Teimuraz; Chelidze, Tamaz; Zhukova, Natalia; Mepharidze, Ekaterine; Sborshchikov, Alexander

    2010-05-01

    Many scientific works on dynamics of earthquake generation are devoted to qualitative and quantitative reproduction of behavior of seismic faults. Number of theoretical, numerical or physical models are already designed for this purpose. Main assumption of these works is that the correct model must be capable to reproduce power law type relation for event sizes with magnitudes greater than or equal to a some threshold value, similar to Gutenberg-Richter (GR) law for the size distribution of earthquakes. To model behavior of a seismic faults in laboratory conditions spring-block experimental systems are often used. They enable to generate stick-slip movement, intermittent behavior occurring when two solids in contact slide relative to each other driven at a constant velocity. Wide interest to such spring-block models is caused by the fact that stick-slip is recognized as a basic process underlying earthquakes generation along pre-existing faults. It is worth to mention, that in stick slip experiments reproduction of power law, in slip events size distribution, with b values close or equal to the one found for natural seismicity is possible. Stick-slip process observed in these experimental models is accompanied by a transient elastic waves propagation generated during the rapid release of stress energy in spring-block system. Oscillations of stress energy can be detected as a characteristic acoustic emission (AE). Accompanying stick slip AE is the subject of intense investigation, but many aspects of this process are still unclear. In the present research we aimed to investigate dynamics of stick slip AE in order to find whether its distributional properties obey power law. Experiments have been carried out on spring-block system consisting of fixed and sliding plates of roughly finished basalt samples. The sliding block was driven with a constant velocity. Experiments have been carried out for five different stiffness of pulling spring. Thus five different regimes of stick slip movement has been maintained. The AE accompanying the elementary slip events of stick-slip process were recorded on a PC sound card. The sensor for the AE was a lead circonate-titanate with a natural frequency of 100 KHz. In order to ensure standard conditions in each experiment, sliding surfaces were sanded up by sandpaper and cleaned of a dust. AE data analysis consisted of signal conditioning, filtering, and correct wave trains separation. Onset time of AE was determined at a minimun of Akaike Information Criterion. Afterwards time series of AE characteristics such as: recurrence times between consecutive AE bursts as well as time intervals between their maximums, duration of AE bursts, energy and power of AE, max by modulus of AE wave train amplitudes, etc. have been compiled. Cumulative probability distributions for all these data sets have been constructed and tested on the subject of GR type power law relation. It was found that characteristics of AE of stick slip process are strongly depending on the movement regime. Number of registered AE essentially increased for stiffer spring. At the same time recurrence times and emitted AE energy decreases. Power law type relation have not been observed for all AE characteristics and not for all considered regimes of movement. Power law relation, close to observed for real seismicity, was found for power of AE time series at stiffer springs. It is interesting that recurrence times between maximums of consecutive AE bursts and duration of AE bursts, reveal b in the range of 0.6-1.65. These results point that experimental conditions of stick slip process including movement regimes should be selected with care to ensure similarity between model and natural seismicity distributional characteristics.

  8. An Object-Oriented Collection of Minimum Degree Algorithms: Design, Implementation, and Experiences

    NASA Technical Reports Server (NTRS)

    Kumfert, Gary; Pothen, Alex

    1999-01-01

    The multiple minimum degree (MMD) algorithm and its variants have enjoyed 20+ years of research and progress in generating fill-reducing orderings for sparse, symmetric positive definite matrices. Although conceptually simple, efficient implementations of these algorithms are deceptively complex and highly specialized. In this case study, we present an object-oriented library that implements several recent minimum degree-like algorithms. We discuss how object-oriented design forces us to decompose these algorithms in a different manner than earlier codes and demonstrate how this impacts the flexibility and efficiency of our C++ implementation. We compare the performance of our code against other implementations in C or Fortran.

  9. Annual Net Community Production in the Western Subtropical North Pacific Determined from Argo-O2 Measurements

    NASA Astrophysics Data System (ADS)

    Yang, B.; Emerson, S. R.; Bushinsky, S. M.

    2016-02-01

    Export of organic carbon from the surface ocean to depth (the biological pump) helps maintain the pCO2 of the atmosphere and the O2 content of the oxygen minimum zones of the ocean. In the upper ocean, at steady state over a seasonal cycle the net organic carbon export is equal to the Annual Net Community Production (ANCP). The geographic distribution of this quantity determined by satellite-predicted Net Primary Production (NPP) and the recycling efficiency in the euphotic zone is more heterogeneous than the limited experimental estimates of ANCP. We evaluate the relationship between these two estimates of ANCP in the subtropical Western North Pacific Ocean ( 165o E and 20o N) using oxygen measurements on Argo Floats. In January of 2015 we deployed four floats with Anderaa oxygen sensors attached to a 60 cm stick on top of the float end cap, which can be readily calibrated against atmospheric pO2. We present data from these floats and air-sea oxygen flux calculations. The degree of oxygen supersaturation in summer is 1-2 percent, and in winter it fluctuates between being over and undersaturated. Evaluating the role of bubbles in winter is critical to an accurate determination of the annual flux. While there is not a full year of data at the time of writing this abstract, there will be when the Ocean Science meeting is held. So far, after nine months of measurements, there is a net flux of oxygen to the atmosphere, indicating that photosynthesis exceeds respiration. In February we will present a full annual cycle of air-sea oxygen flux and an estimate of ANCP in this very rarely studied region of the ocean.

  10. Acoustic and aerodynamic testing of a scale model variable pitch fan

    NASA Technical Reports Server (NTRS)

    Jutras, R. R.; Kazin, S. B.

    1974-01-01

    A fully reversible pitch scale model fan with variable pitch rotor blades was tested to determine its aerodynamic and acoustic characteristics. The single-stage fan has a design tip speed of 1160 ft/sec (353.568 m/sec) at a bypass pressure ratio of 1.5. Three operating lines were investigated. Test results show that the blade pitch for minimum noise also resulted in the highest efficiency for all three operating lines at all thrust levels. The minimum perceived noise on a 200-ft (60.96 m) sideline was obtained with the nominal nozzle. At 44% of takeoff thrust, the PNL reduction between blade pitch and minimum noise blade pitch is 1.8 PNdB for the nominal nozzle and decreases with increasing thrust. The small nozzle (6% undersized) has the highest efficiency at all part thrust conditions for the minimum noise blade pitch setting; although, the noise is about 1.0 PNdB higher for the small nozzle at the minimum noise blade pitch position.

  11. Coagulation of particles in Saturn's rings - Measurements of the cohesive force of water frost

    NASA Technical Reports Server (NTRS)

    Hatzes, A. P.; Bridges, F.; Lin, D. N. C.; Sachtjen, S.

    1991-01-01

    Experimental data are presented on the sticking force of water ice particles which are indicative of the role that the cohesive properties of such particles could play in the dynamics of Saturn ring particles. Sticking forces are dependent on particle impact velocities; a 'Velcro' model is devised to describe the surface structure involved in sticking. The data indicate that below the critical impact velocity of about 0.03 cm/sec, particle cohesion always occurs. Due to the optical depth of micron-sized grains in the Saturn rings, particles are hypothesized to be coated with a layer of frost which will render cohesion an important ring-dynamics process.

  12. Hinge Moment Coefficient Prediction Tool and Control Force Analysis of Extra-300 Aerobatic Aircraft

    NASA Astrophysics Data System (ADS)

    Nurohman, Chandra; Arifianto, Ony; Barecasco, Agra

    2018-04-01

    This paper presents the development of tool that is applicable to predict hinge moment coefficients of subsonic aircraft based on Roskam’s method, including the validation and its application to predict hinge moment coefficient of an Extra-300. The hinge moment coefficients are used to predict the stick forces of the aircraft during several aerobatic maneuver i.e. inside loop, half cuban 8, split-s, and aileron roll. The maximum longitudinal stick force is 566.97 N occurs in inside loop while the maximum lateral stick force is 340.82 N occurs in aileron roll. Furthermore, validation hinge moment prediction method is performed using Cessna 172 data.

  13. Mechanization of and experience with a triplex fly-by-wire backup control system

    NASA Technical Reports Server (NTRS)

    Lock, W. P.; Petersen, W. R.; Whitman, G. B.

    1975-01-01

    A redundant three-axis analog control system was designed and developed to back up a digital fly-by-wire control system for an F-8C airplane. Forty-two flights, involving 58 hours of flight time, were flown by six pilots. The mechanization and operational experience with the backup control system, the problems involved in synchronizing it with the primary system, and the reliability of the system are discussed. The backup control system was dissimilar to the primary system, and it provided satisfactory handling through the flight envelope evaluated. Limited flight tests of a variety of control tasks showed that control was also satisfactory when the backup control system was controlled by a minimum-displacement (force) side stick. The operational reliability of the F-8 digital fly-by-wire control system was satisfactory, with no unintentional downmodes to the backup control system in flight. The ground and flight reliability of the system's components is discussed.

  14. Design of a Minimum Surface-Effect Tendon-Based Microactuator for Micromanipulation

    NASA Technical Reports Server (NTRS)

    Goldfarb, Michael; Lipsey, James H.

    1997-01-01

    A piezoelectric (PZT) stack-based actuator was developed to provide a means of actuation with dynamic characteristics appropriate for small-scale manipulation. In particular, the design incorporates a highly nonlinear, large-ratio transmission that provides approximately two orders of magnitude motion amplification from the PZT stack. In addition to motion amplification, the nonlinear transmission was designed via optimization methods to distort the highly non-uniform properties of a piezoelectric actuator so that the achievable actuation force is nearly constant throughout the actuator workspace. The package also includes sensors that independently measure actuator output force and displacement, so that a manipulator structure need not incorporate sensors nor the associated wires. Specifically, the actuator was designed to output a maximum force of at least one Newton through a stroke of at least one millimeter. For purposes of small-scale precision position and/or force control, the actuator/sensor package was designed to eliminate stick-slip friction and backlash. The overall dimensions of the actuator/sensor package are approximately 40 x 65 x 25 mm.

  15. Methods for genetic transformation of filamentous fungi.

    PubMed

    Li, Dandan; Tang, Yu; Lin, Jun; Cai, Weiwen

    2017-10-03

    Filamentous fungi have been of great interest because of their excellent ability as cell factories to manufacture useful products for human beings. The development of genetic transformation techniques is a precondition that enables scientists to target and modify genes efficiently and may reveal the function of target genes. The method to deliver foreign nucleic acid into cells is the sticking point for fungal genome modification. Up to date, there are some general methods of genetic transformation for fungi, including protoplast-mediated transformation, Agrobacterium-mediated transformation, electroporation, biolistic method and shock-wave-mediated transformation. This article reviews basic protocols and principles of these transformation methods, as well as their advantages and disadvantages.

  16. Voluntary environmental agreements: Good or bad news for environmental protection?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Segerson, K.; Miceli, T.J.

    1998-09-01

    There has been growing interest in the use of voluntary agreements (VAs) as an environmental policy tool. This article uses a simple model to determine whether VAs are likely to lead to efficient environmental protection. The authors consider cases where polluters are induced to participate either by a background threat of mandatory controls (the stick approach) or by cost-sharing subsidies (the carrot approach). The results suggest that the overall impact on environmental quality could be positive or negative, depending on a number of factors, including the allocation of bargaining power, the magnitude of the background threat, and the social costmore » of funds.« less

  17. Offensive Words, Lethal Weapons

    ERIC Educational Resources Information Center

    Jacoby, Russell

    2007-01-01

    The old childhood ditty "sticks and stones may break my bones, but words will never hurt me" has proved wiser than the avalanche of commentary provoked by the recent insults by Don Imus and the killings at Virginia Tech. Our society forbids public name-calling but allows sticks and stones. Anyone can acquire a gun, but everyone must be…

  18. Effect of hinge-moment parameters on elevator stick forces in rapid maneuvers

    NASA Technical Reports Server (NTRS)

    Jones, Robert T; Greenberg, Harry

    1944-01-01

    The importance of the stick force per unit normal acceleration as a criterion of longitudinal stability and the critical dependence of this gradient on elevator hinge-moment parameters have been shown in previous reports. The present report continues the investigation with special reference to transient effects for maneuvers of short duration.

  19. "Fist, Stick, Knife, Gun": Getting Real in Upward Bound.

    ERIC Educational Resources Information Center

    Pace, Barbara G.; Adkins, Theresa A.

    2002-01-01

    Describes how a teacher found literature for Upward Bound students. Presents Geoffrey Canada's "Fist, Stick, Knife, Gun: A Personal History of Violence in America" as a nonfiction work to provide clarity and connections that might not have been available in a fictional work, yet it had elements of literary fiction that made the text…

  20. The Donkey and the Stick: Revisited.

    ERIC Educational Resources Information Center

    Smith, Clifford E.

    The fable of the "Donkey and the Stick" is used as an analogy to present day industrial relations problems. The managerial approach of autocratic leadership has long since outlived its usefulness; rewards based along Maslow's hierarchy of needs should be used for employee motivation. The point is made from the fable that employees can't be…

  1. Development by extrusion of soyabari snack sticks: a nutritionally improved soya-maize product based on the Nigerian snack (kokoro).

    PubMed

    Omueti, O; Morton, I D

    1996-01-01

    A nutritionally improved local snack compared to existing kokoro has been developed by extrusion cooking of different formulations of maize, soybean and condiments such as pepper, onion, salt, palm oil, plantain and banana. The improved snack was named as the 'soyabari snack stick'. The chemical composition of representative extruded products indicates a high level of crude protein, fat, energy, available lysine and improved in vitro digestibility compared to the usual maize-based products. The level of stachyose and raffinose were greatly reduced in the extruded products compared to raw soya. Formulations using various additives yielded products suitable for different consumers' preferences such as hot, sweet, bland, gritty or crispy and acceptable to taste assessors. Soyabari snack sticks were equally acceptable as Bombay mix, a product on the market in London. Sensory analysis showed no significant differences in the two products but the crude fibre content of Bombay mix was higher while the protein was slightly lower than for soyabari sticks. Local ingredients can produce acceptable extrudates.

  2. The dissociative chemisorption of methane on Ni(100) and Ni(111): Classical and quantum studies based on the reaction path Hamiltonian

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mastromatteo, Michael; Jackson, Bret, E-mail: jackson@chem.umass.edu

    Electronic structure methods based on density functional theory are used to construct a reaction path Hamiltonian for CH{sub 4} dissociation on the Ni(100) and Ni(111) surfaces. Both quantum and quasi-classical trajectory approaches are used to compute dissociative sticking probabilities, including all molecular degrees of freedom and the effects of lattice motion. Both approaches show a large enhancement in sticking when the incident molecule is vibrationally excited, and both can reproduce the mode specificity observed in experiments. However, the quasi-classical calculations significantly overestimate the ground state dissociative sticking at all energies, and the magnitude of the enhancement in sticking with vibrationalmore » excitation is much smaller than that computed using the quantum approach or observed in the experiments. The origin of this behavior is an unphysical flow of zero point energy from the nine normal vibrational modes into the reaction coordinate, giving large values for reaction at energies below the activation energy. Perturbative assumptions made in the quantum studies are shown to be accurate at all energies studied.« less

  3. The Hockey Stick and the Climate Wars: Dispatches From The Front Lines

    NASA Astrophysics Data System (ADS)

    Mann, M. E.

    2011-12-01

    A central figure in the controversy over human-caused climate change has been The Hockey Stick, a simple, easy-to-understand graph my colleagues and I constructed to depict changes in Earth's temperature back to 1000 AD. The graph was featured in the high-profile Summary for Policy Makers of the 2001 report of the Intergovernmental Panel on Climate Change (IPCC), and it quickly became an icon in the debate over human-caused (anthropogenic) climate change. I will tell the story behind the Hockey Stick, using it as a vehicle for exploring broader issues regarding the role of skepticism in science, the uneasy relationship between science and politics, and the dangers that arise when special economic interests and those who do their bidding attempt to skew the discourse over policy-relevant areas of science. In short, I attempt to use the Hockey Stick to cut through the fog of disinformation that has been generated by the campaign to deny the reality of climate change. It is my intent, in so doing, to reveal the very real threat to our future that lies behind it.

  4. Waffle Production: Influence of Baking Plate Material on Sticking of Waffles.

    PubMed

    Huber, Regina; Kalss, Georg; Schoenlechner, Regine

    2017-01-01

    Background of this study was to understand the factors that contribute to sticking of fresh egg waffles on baking plates. The aim of this study was to investigate the sticking (adhesion) behavior of waffles on 4 different baking plate materials (ductile iron, grey iron, low alloyed steel, and steel with titanium nitrite coating) at different baking parameters (temperature and time) and application of 3 different release agents (different fat compositions). Baking plates from ductile and grey iron showed lower release properties of waffles than the 2 steel baking plates. Baking parameters had to be high enough to allow rapid product crust formation but prevent burning, which again increases sticking behavior. Release agents based on short-chain fatty acids with higher degree of saturation provided better release behavior of waffles than those based on long-chain fatty acids or on emulsifier-acid combinations. Baking plates with increased hardness, good heat storage capacity, and smooth surface seemed to be best suitable. Further research on appropriate coating material might be promising for future. © 2016 Institute of Food Technologists®.

  5. Custom-Made Finger Guard to Prevent Wire-Stick Injury to the Operator's Finger while Performing Intermaxillary Fixation.

    PubMed

    Kumaresan, Ramesh; Ponnusami, Karthikeyan; Karthikeyan, Priyadarshini

    2014-12-01

    The treatment of maxillofacial fractures involves different methods from bandages and splinting to methods of open reduction and internal fixation and usually requires control of the dental occlusion with the help of intermaxillary fixation (IMF). Different wiring techniques have been used to aid in IMF including placement of custom-made arch bars, eyelet etc. However, these wiring techniques are with a constant danger of trauma to the surgeon's fingers by their sharp ends. Though there exist a variety of commercially available barrier products and customized techniques to prevent wire-stick injury, cost factor, touch sensitivity, and comfort aspect restrain their acquirement and exploit. This technical note describes the construction of a simple and economical finger guard made of soft thermoplastic material that provides an added protection to fingers from wire-stick type injuries, and its flexible nature permits a comfortable finger flexion movement and acceptable touch sensitivity. This is a simple, economical, reusable puncture, and cut-resistance figure guard by which we can avoid wire-stick type injury to the operator's fingers during wiring technique.

  6. Miniature stick-packaging--an industrial technology for pre-storage and release of reagents in lab-on-a-chip systems.

    PubMed

    van Oordt, Thomas; Barb, Yannick; Smetana, Jan; Zengerle, Roland; von Stetten, Felix

    2013-08-07

    Stick-packaging of goods in tubular-shaped composite-foil pouches has become a popular technology for food and drug packaging. We miniaturized stick-packaging for use in lab-on-a-chip (LOAC) systems to pre-store and on-demand release the liquid and dry reagents in a volume range of 80-500 μl. An integrated frangible seal enables the pressure-controlled release of reagents and simplifies the layout of LOAC systems, thereby making the package a functional microfluidic release unit. The frangible seal is adjusted to defined burst pressures ranging from 20 to 140 kPa. The applied ultrasonic welding process allows the packaging of temperature sensitive reagents. Stick-packs have been successfully tested applying recovery tests (where 99% (STDV = 1%) of 250 μl pre-stored liquid is released), long-term storage tests (where there is loss of only <0.5% for simulated 2 years) and air transport simulation tests. The developed technology enables the storage of a combination of liquid and dry reagents. It is a scalable technology suitable for rapid prototyping and low-cost mass production.

  7. The effect of vacuum packaging on histamine changes of milkfish sticks at various storage temperatures.

    PubMed

    Kung, Hsien-Feng; Lee, Yi-Chen; Lin, Chiang-Wei; Huang, Yu-Ru; Cheng, Chao-An; Lin, Chia-Min; Tsai, Yung-Hsiang

    2017-10-01

    The effects of polyethylene packaging (PEP) (in air) and vacuum packaging (VP) on the histamine related quality of milkfish sticks stored at different temperatures (-20°C, 4°C, 15°C, and 25°C) were studied. The results showed that the aerobic plate count (APC), pH, total volatile basic nitrogen (TVBN), and histamine contents increased as storage time increased when the PEP and VP samples were stored at 25°C. At below 15°C, the APC, TVBN, pH, and histamine levels in PEP and VP samples were retarded, but the VP samples had considerably lower levels of APC, TVBN, and histamine than PEP samples. Once the frozen fish samples stored at -20°C for 2 months were thawed and stored at 25°C, VP retarded the increase of histamine in milkfish sticks as compared to PEP. In summary, this result suggested the milkfish sticks packed with VP and stored below 4°C could prevent deterioration of product quality and extend shelf-life. Copyright © 2017. Published by Elsevier B.V.

  8. A geophone wireless sensor network for investigating glacier stick-slip motion

    NASA Astrophysics Data System (ADS)

    Martinez, Kirk; Hart, Jane K.; Basford, Philip J.; Bragg, Graeme M.; Ward, Tyler; Young, David S.

    2017-08-01

    We have developed an innovative passive borehole geophone system, as part of a wireless environmental sensor network to investigate glacier stick-slip motion. The new geophone nodes use an ARM Cortex-M3 processor with a low power design capable of running on battery power while embedded in the ice. Only data from seismic events was stored, held temporarily on a micro-SD card until they were retrieved by systems on the glacier surface which are connected to the internet. The sampling rates, detection and filtering levels were determined from a field trial using a standard commercial passive seismic system. The new system was installed on the Skalafellsjökull glacier in Iceland and provided encouraging results. The results showed that there was a relationship between surface melt water production and seismic event (ice quakes), and these occurred on a pattern related to the glacier surface melt-water controlled velocity changes (stick-slip motion). Three types of seismic events were identified, which were interpreted to reflect a pattern of till deformation (Type A), basal sliding (Type B) and hydraulic transience (Type C) associated with stick-slip motion.

  9. Shear bond strength of different retainer wires and bonding adhesives in consideration of the pretreatment process.

    PubMed

    Reicheneder, Claudia; Hofrichter, Bernd; Faltermeier, Andreas; Proff, Peter; Lippold, Carsten; Kirschneck, Christian

    2014-11-28

    We aimed to compare the shear bond strength (SBS) of three different retainer wires and three different bonding adhesives in consideration of the pretreatment process of enamel surface sandblasting. 400 extracted bovine incisors were divided into 10 groups of 20 paired specimens each. 10 specimens of each group were pretreated by enamel sandblasting. The retainer wires Bond-A-Braid™, GAC-Wildcat®-Twistflex and everStick®ORTHO were bonded to the teeth with the adhesives Transbond™-LR, Tetric-EvoFlow™ and Stick®FLOW and then debonded measuring the SBS. While sandblasting generally increased SBS for all tested combinations, the retainer wires bonded with Transbond™-LR showed the highest SBS both with and without prior sandblasting. Significantly lower SBS were found for Tetric-EvoFlow™ that were comparable to those for everStick®ORTHO. Pretreatment of enamel surfaces by sandblasting increased the SBS of all retainer-wires. Transbond™-LR showed the best results compared to Tetric-EvoFlow™ and everStick®ORTHO, while all combinations used provided sufficient bonding strengths for clinical use.

  10. Reduced-order modeling approach for frictional stick-slip behaviors of joint interface

    NASA Astrophysics Data System (ADS)

    Wang, Dong; Xu, Chao; Fan, Xuanhua; Wan, Qiang

    2018-03-01

    The complex frictional stick-slip behaviors of mechanical joint interface have a great effect on the dynamic properties of assembled structures. In this paper, a reduced-order modeling approach based on the constitutive Iwan model is proposed to describe the stick-slip behaviors of joint interface. An improved Iwan model is developed to describe the non-zero residual stiffness at macro-slip regime and smooth transition of joint stiffness from micro-slip to macro-slip regime, and the power-law relationship of energy dissipation during the micro-slip regime. In allusion to these nonlinear behaviors, the finite element method is used to calculate the recycle force under monolithic loading and the energy dissipation per cycle under oscillatory loading. The proposed model is then used to predict the nonlinear stick-slip behaviors of joint interface by curve-fitting to the results of finite element analysis, and the results show good agreements with the finite element analysis. A comparison with the experiment results in literature is also made. The proposed model agrees very well with the experiment results.

  11. [Comparison of clinical effects of Co-Cr alloy cast post-core and everStick fiber post in restoration of labially or lingually inclined maxillary central incisor].

    PubMed

    Qian, Yu-Mei; Zhong, Qun; Chen, Shuang

    2017-02-01

    To compare the clinical effect of Co-Cr alloy cast post-core and everStick fiber post in restoration of maxillary central incisor with labial or lingual inclination, and provide theoretical basis for clinical application. Ninety-seven labially or lingually inclined maxillary central incisors were treated in our hospital from March 2012 to March 2014. The patients were randomly divided into group A (n=49) and group B (n=48), and received post -core and crown restoration. Patients in group A underwent Co-Cr alloy cast post and core restoration and patients in group B underwent everStick fiber post and core restoration. After two-year of follow-up, root fracture, post break, crown or post dislodgment and gingival marginal discoloration were recorded and analyzed using SPSS 19.0 software package. Chi-square test showed that the success rate of restoration was significantly different between 2 groups (P<0.05). The incidence of root fracture and gingival marginal discoloration of Co-Cr alloy cast post-core was higher than that of everStick fiber post, but there was no significant difference in the incidence of post break, crown or post dislodgment. EverStick fiber post is better than Co-Cr alloy cast post and core to prevent root fracture and gingival marginal discoloration. Its fracture pattern is repairable and favorable for preserving tooth.

  12. Effect of Arrangement of Stick Figures on Estimates of Proportion in Risk Graphics

    PubMed Central

    Ancker, Jessica S.; Weber, Elke U.; Kukafka, Rita

    2017-01-01

    Background Health risks are sometimes illustrated with stick figures, with a certain proportion colored to indicate they are affected by the disease. Perception of these graphics may be affected by whether the affected stick figures are scattered randomly throughout the group or arranged in a block. Objective To assess the effects of stick-figure arrangement on first impressions of estimates of proportion, under a 10-s deadline. Design Questionnaire. Participants and Setting Respondents recruited online (n = 100) or in waiting rooms at an urban hospital (n = 65). Intervention Participants were asked to estimate the proportion represented in 6 unlabeled graphics, half randomly arranged and half sequentially arranged. Measurements Estimated proportions. Results Although average estimates were fairly good, the variability of estimates was high. Overestimates of random graphics were larger than overestimates of sequential ones, except when the proportion was near 50%; variability was also higher with random graphics. Although the average inaccuracy was modest, it was large enough that more than one quarter of respondents confused 2 graphics depicting proportions that differed by 11 percentage points. Low numeracy and educational level were associated with inaccuracy. Limitations Participants estimated proportions but did not report perceived risk. Conclusions Randomly arranged arrays of stick figures should be used with care because viewers’ ability to estimate the proportion in these graphics is so poor that moderate differences between risks may not be visible. In addition, random arrangements may create an initial impression that proportions, especially large ones, are larger than they are. PMID:20671209

  13. Functionally Different Pads on the Same Foot Allow Control of Attachment: Stick Insects Have Load-Sensitive “Heel” Pads for Friction and Shear-Sensitive “Toe” Pads for Adhesion

    PubMed Central

    Labonte, David; Federle, Walter

    2013-01-01

    Stick insects (Carausius morosus) have two distinct types of attachment pad per leg, tarsal “heel” pads (euplantulae) and a pre-tarsal “toe” pad (arolium). Here we show that these two pad types are specialised for fundamentally different functions. When standing upright, stick insects rested on their proximal euplantulae, while arolia were the only pads in surface contact when hanging upside down. Single-pad force measurements showed that the adhesion of euplantulae was extremely small, but friction forces strongly increased with normal load and coefficients of friction were 1. The pre-tarsal arolium, in contrast, generated adhesion that strongly increased with pulling forces, allowing adhesion to be activated and deactivated by shear forces, which can be produced actively, or passively as a result of the insects' sprawled posture. The shear-sensitivity of the arolium was present even when corrected for contact area, and was independent of normal preloads covering nearly an order of magnitude. Attachment of both heel and toe pads is thus activated partly by the forces that arise passively in the situations in which they are used by the insects, ensuring safe attachment. Our results suggest that stick insect euplantulae are specialised “friction pads” that produce traction when pressed against the substrate, while arolia are “true” adhesive pads that stick to the substrate when activated by pulling forces. PMID:24349156

  14. 'Food Sticking in My Throat': Videofluoroscopic Evaluation of a Common Symptom.

    PubMed

    Madhavan, Aarthi; Carnaby, Giselle D; Crary, Michael A

    2015-06-01

    Prevalence of the symptom of food 'sticking' during swallowing has been reported to range from 5 to 50%, depending on the assessment setting. However, limited objective evidence has emerged to clarify factors that contribute to this symptom. Three hundred and fifteen patient records from an outpatient dysphagia clinic were reviewed to identify patients with symptoms of 'food sticking in the throat.' Corresponding videofluoroscopic swallowing studies for patients with this complaint were reviewed for the following variables: accuracy of symptom localization, identification and characteristics (anatomic, physiologic) of an explanatory cause for the symptom, and the specific swallowed material that identified the explanatory cause. One hundred and forty one patients (45%) were identified with a complaint of food 'sticking' in their throat during swallowing. Prevalence of explanatory findings on fluoroscopy was 76% (107/141). Eighty five percent (91/107) of explanatory causes were physiologic in nature, while 15% (16/107) were anatomic. The majority of explanatory causes were identified in the esophagus (71%). Symptom localization was more accurate when the explanatory cause was anatomic versus physiologic (75 vs. 18%). A non-masticated marshmallow presented with the highest diagnostic yield in identification of explanatory causes (71%). Patients complaining of 'food sticking in the throat' are likely to present with esophageal irregularities. Thus, imaging studies of swallowing function should include the esophagus. A range of materials, including a non-masticated marshmallow, is helpful in determining the location and characteristics of swallowing deficits contributing to this symptom.

  15. Sensory neuroanatomy of stick insects highlights the evolutionary diversity of the orthopteroid subgenual organ complex.

    PubMed

    Strauß, Johannes; Lakes-Harlan, Reinhard

    2013-11-01

    The subgenual organ is a scolopidial sense organ located in the tibia of many insects. In this study the neuroanatomy of the subgenual organ complex of stick insects is clarified for two species, Carausius morosus and Siyploidea sipylus. Neuronal tracing shows a subgenual organ complex that consists of a subgenual organ and a distal organ. There are no differences in neuroanatomy between the three thoracic leg pairs, and the sensory structures are highly similar in both species. A comparison of the neuroanatomy with other orthopteroid insects highlights two features unique in Phasmatodea. The subgenual organ contains a set of densely arranged sensory neurons in the anterior-ventral part of the organ, and a distal organ with 16-17 scolopidial sensilla in C. morosus and 20-22 scolopidial sensilla in S. sipylus. The somata of sensory neurons in the distal organ are organized in a linear array extending distally into the tibia, with only a few exceptions of closely associated neurons. The stick insect sense organs show a case of an elaborate scolopidial sense organ that evolved in addition to the subgenual organ. The neuroanatomy of stick insects is compared to that studied in other orthopteroid taxa (cockroaches, locusts, crickets, tettigoniids). The comparison of sensory structures indicates that elaborate scolopidial organs have evolved repeatedly among orthopteroids. The distal organ in stick insects has the highest number of sensory neurons known for distal organs so far. Copyright © 2013 Wiley Periodicals, Inc.

  16. 50 CFR 600.330 - National Standard 5-Efficiency.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Efficiency. In theory, an efficient fishery would harvest the OY with the minimum use of economic inputs such... techniques of harvesting, processing, or marketing, and should avoid creating strong incentives for excessive...

  17. Next generation sequencing of oral microbiota in Type 2 diabetes mellitus prior to and after neem stick usage and correlation with serum monocyte chemoattractant-1.

    PubMed

    Anbalagan, Rubini; Srikanth, Padma; Mani, Monika; Barani, Ramya; Seshadri, Krishna G; Janarthanan, R

    2017-08-01

    Oral microbiome impacts health and disease. T2DM and periodontitis are associated. Neem (Azadiracta indica) has antibacterial activity against oral microbiota. To characterize oral microbiota (OMB) in saliva samples of T2DM patients by Next generation sequencing. To analyze MCP-1 levels among the T2DM patients before and after a month of neem stick usage as a toothbrush. Blood and saliva samples were collected from adult T2DM patients before and after the neem stick usage. Metagenomic sequencing was performed on saliva samples targeting V6 region of 16s rRNA. Serum MCP-1 levels were determined using a quantitative sandwich Human MCP-1 standard ABTS development kit (Peprotech, USA). The profile of oral microbiota of T2DM patients (n=24) consists of Streptococcus (95.8%) counts ranging from 2644 to 27,214, Veillonella (72.2%, counts 25-19,709, Neisseria (87.5%) 453-33,445), Rothia (63.6%, 233-6734), Actinomycetes (25%, 161-3730), Fusobacterium (21%, 2252-21,334), and Pigmentiphaga (12.5% 3-16,644). Oral microbiota in healthy controls (n=10), consists of Streptococcus (26.1%), Veillonella (21.9%), Neisseria (16.9%), Haemophilus (10.7%), Actinomycetes (2.6%), Rothia (3.1%), Oribacterium (1.7%). Post neem samples showed drastic reduction in the load of bacteria which was statistically significant. The mean serum MCP-1 before the use of neem stick was 265.18±79.44 (range 141.6-980.5pg/ml) and dropped to 33.6±7.35 after a month of neem stick usage (P value>0.001). OMB of T2DM patients and healthy controls were similar, however bacterial loads were significantly higher in T2DM patients. Use of neem stick has a statistically significant reduction on bacterial loads and MCP-1 levels in T2DM patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. The femur-tibia control system in a proscopiid (Caelifera, Orthoptera): a test for assumptions on the functional basis and evolution of twig mimesis in stick insects.

    PubMed

    Wolf, H; Bässler, U; Spiess, R; Kittmann, R

    2001-11-01

    The extremely slow return movements observed in stick insects (phasmids) after imposed changes in posture are termed catalepsy. In the literature, catalepsy is treated as a behavioural component of the twig mimesis observed in walking stick insects. It is produced by the high gain of the velocity-sensitive component of the relevant joint control systems and by the non-linear dependency of its time constant on movement velocity. The high gain, in turn, causes the system to work close to instability, and this may have driven the evolution of gain control mechanisms. Although these statements represent plausible assumptions, based on correlated occurrence, they remain largely hypothetical like many ideas concerning evolutionary tendencies. To test these hypotheses, we studied catalepsy and the relevant properties of the femur-tibia control system in the middle and hind legs of Prosarthria teretrirostris.cf. Prosarthria teretrirostris is a proscopiid closely related to grasshoppers and locusts. With its slender, green-to-brown body and legs, it shows clear morphological twig mimesis, which has evolved independently of the well-known twig mimesis in stick insects. The animals show clear catalepsy. The main properties of femur-tibia joint control are remarkably similar between proscopiids and stick insects (e.g. the marked sensitivity to movement velocity rather than to joint position and the non-linear dependency of the time constants of response decay on movement velocity), but there are also important differences (habituation and activity-related mechanisms of gain control are absent). Together, these results validate the main concepts that have been developed concerning the neural basis and evolution of catalepsy in stick insects and its relationship to twig mimesis, while demonstrating that ideas on the role of habituation and gain control should be refined.

  19. Carbonyl emissions from a novel heated tobacco product (IQOS): comparison with an e-cigarette and a tobacco cigarette.

    PubMed

    Farsalinos, Konstantinos E; Yannovits, Nikoletta; Sarri, Theoni; Voudris, Vassilis; Poulas, Konstantinos; Leischow, Scott

    2018-06-19

    To measure carbonyl emissions from a heated tobacco product (IQOS) in comparison with an e-cigarette (Nautilus Mini) and a commercial tobacco cigarette (Marlboro Red). Regular and menthol variants of the heated tobacco product were tested. A tank-type atomizer was tested with a tobacco-flavoured liquid at 10 W and 14 W. Aerosol and smoke were collected in impingers containing 2,4-dinitrophenylhydrazine. Health Canada Intense and two more intense puffing regimes were used. Analytical laboratory in Greece. Carbonyl levels in the aerosol and smoke. At Health Canada Intense regime, heated tobacco products emitted 5.0-6.4 μg/stick formaldehyde, 144.1-176.7 μg/stick acetaldehyde, 10.4-10.8 μg/stick acrolein, 11.0-12.8 μg/stick propionaldehyde and 1.9-2.0 μg/stick crotonaldehyde. Compared with the tobacco cigarette, levels were on average 91.6% lower for formaldehyde, 84.9% lower for acetaldehyde, 90.6% lower for acrolein, 89.0% lower for propionaldehyde and 95.3% lower for crotonaldehyde. The e-cigarette emitted 0.5-1.0 μg/12 puffs formaldehyde, 0.8-1.5μg/12 puffs acetaldehyde and 0.3-0.4 μg/12 puffs acrolein, but no propionaldehyde and crotonaldehyde. At more intense puffing regimes, formaldehyde was increased in heated tobacco products, but levels were 3 to 4-fold lower compared with the tobacco cigarette. Based on the findings from Health Canada Intense puffing regime, use of 20 heated tobacco sticks would result in 81.7-97.9% reduced carbonyl exposure compared with smoking 20 tobacco cigarettes; the respective reduction in exposure from use of 5 g e-cigarette liquid would be 92.2-99.8%. The IQOS heated tobacco product emits substantially lower levels of carbonyls than a commercial tobacco cigarette (Marlboro Red) but higher levels than a Nautilus Mini e-cigarette. This article is protected by copyright. All rights reserved.

  20. Confronting Regulatory Cost and Quality Expectations. An Exploration of Technical Change in Minimum Efficiency Performance Standards

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Taylor, Margaret; Spurlock, C. Anna; Yang, Hung-Chia

    The dual purpose of this project was to contribute to basic knowledge about the interaction between regulation and innovation and to inform the cost and benefit expectations related to technical change which are embedded in the rulemaking process of an important area of national regulation. The area of regulation focused on here is minimum efficiency performance standards (MEPS) for appliances and other energy-using products. Relevant both to U.S. climate policy and energy policy for buildings, MEPS remove certain product models from the market that do not meet specified efficiency thresholds.

  1. Nonspiking local interneurons in insect leg motor control. I. Common layout and species-specific response properties of femur-tibia joint control pathways in stick insect and locust.

    PubMed

    Büschges, A; Wolf, H

    1995-05-01

    1. Locusts (Locusta migratoria) and stick insects (Carausius morosus) exhibit different strategies for predator avoidance. Locusts rely primarily on walking and jumping to evade predators, whereas stick insects become cataleptic, catalepsy forming a major component of the twig mimesis exhibited by this species. The neuronal networks that control postural leg movements in locusts and stick insects are tuned differently to their specific behavioral tasks. An important prerequisite for the production of catalepsy in the stick insect is the marked velocity dependency of the control network, which appears to be generated at the level of nonspiking local interneurons. We examined interneuronal pathways in the network controlling the femur-tibia joint of the locust middle leg and compared its properties with those described for the stick insect middle leg. It was our aim to identify possible neural correlates of the species-specific behavior with regard to postural leg motor control. 2. We obtained evidence that the neuronal networks that control the femur-tibia joints in the two species consist of morphologically and physiologically similar--and thus probably homologous--interneurons. Qualitatively, these interneurons receive the same input from the femoral chordotonal organ receptors and they drive the same pools of leg motoneurons in both species. 3. Pathways that contribute to the control of the femur-tibia joint include interneurons that support both "resisting" and "assisting" responses with respect to the motoneuron activity that is actually elicited during reflex movements. Signal processing via parallel, antagonistic pathways therefore appears to be a common principle in insect leg motor control. 4. Differences between the two insect species were found with regard to the processing of velocity information provided by the femoral chordotonal organ. Interneuronal pathways are sensitive to stimulus velocity in both species. However, in the locust there is no marked velocity dependency of the interneuronal responses, whereas in the same interneurons of the stick insect it is pronounced. This characteristic was maintained at the level of the motoneurons controlling the femur-tibia joint. Pathways for postural leg motor control in the locust thus lack an important prerequisite for the generation of catalepsy, that is, a marked velocity dependency.

  2. The Microseismicity of Glacier Sliding

    NASA Astrophysics Data System (ADS)

    Walter, Fabian; Röösli, Claudia; Kissling, Edi

    2017-04-01

    Our understanding of glacier and ice sheet basal motion remains incomplete. The past decades have witnessed a shift away from initially proposed hard bed theories towards soft, till-laden beds, which deform and thus participate in basal motion. The theoretical treatment of deformable beds is subject to debate, yet our capability to predict ice sheet flow and ultimately sea level rise is contingent upon correct parameterization of basal motion (Ritz et al., 2015). Both hard and soft bed theories neglect frictional sliding across distinct basal fault planes and elastic deformation in response to sudden dislocation. Over recent years, this view has been repeatedly challenged as more and more studies report seismogenic faulting associated with basal sliding. For instance, large parts of the Whillans Ice Stream at Antarctica's Siple Coast move nearly exclusively during sudden sliding episodes (Wiens et al., 2008). This "stick-slip motion" is difficult to explain with traditional glacier sliding theories but more analogous to earthquake dislocation on tectonic faults. Although the Whillans Ice Stream motion may be an extreme example, there exists evidence for much smaller microseismic stick-slip events beneath the Greenland Ice Sheet and non-polar glaciers (Podolskiy and Walter, 2016). This raises the question how relevant and widespread the stick-slip phenomenon is and if it is necessary to include it into ice sheet models. Here we discuss recent seismic deployments, which focused on detection of stick-slip events beneath the Greenland Ice Sheet and European Alpine Glaciers. For all deployments, a considerable challenge lies in detection of stick-slip seismograms in the presence of a dominant background seismicity associated with surface crevassing. Nevertheless, automatic search algorithms and waveform characteristics provide important insights into temporal variation of stick-slip activity as well as information about fault plane geometry and co-seismic sliding direction. REFERENCES E.A. Podolskiy and F. Walter (2016). Cryo-seismology. Reviews of Geophysics. Ritz, C., Edwards, T. L., Durand, G., Payne, A. J., Peyaud, V., & Hindmarsh, R. C. (2015). Potential sea-level rise from Antarctic ice-sheet instability constrained by observations. Nature, 528(7580), 115-118. Wiens, D. A., Anandakrishnan, S., Winberry, J. P., & King, M. A. (2008). Simultaneous teleseismic and geodetic observations of the stick-slip motion of an Antarctic ice stream. Nature, 453(7196), 770-774.

  3. Beaver Activity, Holocene Climate and Riparian Landscape Change Across Stream Scales in the Greater Yellowstone Ecosystem

    NASA Astrophysics Data System (ADS)

    Levine, R.; Meyer, G. A.

    2013-12-01

    Beaver (Castor canadensis) have been part of the fluvial and riparian landscape across much of North America since the Pleistocene, increasing channel habitat complexity and expanding riparian landscapes. The fur trade, however, decimated beaver populations by the 1840s, and other human activities have limited beaver in many areas, including parts of the Greater Yellowstone Ecosystem (GYE). Understanding fluctuations in beaver occupation through the Holocene will aid in understanding the natural range of variability in beaver activity as well as climatic and anthropogenic impacts to fluvial systems. We are developing a detailed chronology of beaver-assisted sedimentation and overall fluvial activity for Odell and Red Rock Creeks (basin areas 83 and 99 km2) in Centennial Valley (CV), Montana, to augment related studies on the long-term effects of beaver on smaller GYE fluvial systems (basin areas 0.1-50 km2). In developing the CV chronology, we use the presence of concentrations of beaver-chewed sticks as a proxy for beaver occupancy. Beaver-stick deposits are found in paleochannel and fluvial terrace exposures. The relative ages of exposures were determined by elevation data from airborne LiDAR and ground surveys. Numerical ages were obtained from 36 14C ages (~30 more are pending) of beaver-stick wood collected during investigation of the stratigraphy. Most beaver-stick deposits are associated with ~ 1 meter of fine-grained sediment, interpreted as overbank deposits, commonly overlying gravelly sand or pebble gravel channel deposits which is consistent with enhanced overbank sedimentation associated with active beaver dams in CV streams. The CV deposits differ from those on smaller GYE streams where beaver-stick deposits are associated with abandoned dams (berms), infilled ponds and laminated sediments. The lack of pond-related deposition associated with CV beaver-stick deposits is consistent with frequent dam breaching (≤ 5 years) in the modern channel of Odell Creek. On all GYE streams investigated, beaver have promoted deposition of a large volume of fine-grained organic-rich sediment, but valley-floor aggradation (vertical rise) due to beaver damming is limited to < 2.5 m, the maximum height of beaver dams, except in glacial depressions where filling occurs without damming. Initial beaver-stick deposit ages for CV streams show notable clustering ca. 5200-5000, 3800-3600, and 900-550 cal yr BP, in part consistent with other GYE sites, where ages tend to cluster in colder-wetter intervals. Beaver-stick deposits from 900-550 cal yr BP, however, overlap the drought-prone Medieval Climate Anomaly (MCA) (~1050-650 cal yr BP), a time of major fire-related debris-flow activity in Yellowstone, and minimal beaver-pond sedimentation in smaller GYE streams. The presence of beaver-stick deposits during the MCA may indicate the importance of larger streams like Odell and Red Rock Creeks in maintaining riparian zones and beaver refugia in drought-prone episodes, a critical concern with current and future warming. Overall, the long-term perspective on beaver occupancy in the GYE across a variety of stream scales provides insight into the effects of climate on ecologically critical riparian zones.

  4. Efficient synthesis of new 2,3-dihydrooxazole-spirooxindoles hybrids as antimicrobial agents.

    PubMed

    Tiwari, Shailendra; Pathak, Poonam; Sagar, Ram

    2016-05-15

    Two series of new 2,3-dihydrooxazole-spirooxindole derivatives were efficiently synthesized starting from N'-(2-oxoindolin-3-ylidene) benzohydrazide/N'-(2-oxoindolin-3-ylidene)-2-phenoxyacetohydrazide using designed synthetic route. Newly synthesized 2,3-dihydrooxazole-spirooxindole derivatives were screened for their antibacterial and antifungal activity against different pathogenic strain of bacteria and fungi. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum fungicidal concentration (MFC) were determined for the test compounds as well as for reference standards. Compounds 4e, 4g, 7g have shown good antibacterial activity whereas compounds 4f, 7b, 7d have displayed better antifungal activity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Power and Efficiency Optimized in Traveling-Wave Tubes Over a Broad Frequency Bandwidth

    NASA Technical Reports Server (NTRS)

    Wilson, Jeffrey D.

    2001-01-01

    A traveling-wave tube (TWT) is an electron beam device that is used to amplify electromagnetic communication waves at radio and microwave frequencies. TWT's are critical components in deep space probes, communication satellites, and high-power radar systems. Power conversion efficiency is of paramount importance for TWT's employed in deep space probes and communication satellites. A previous effort was very successful in increasing efficiency and power at a single frequency (ref. 1). Such an algorithm is sufficient for narrow bandwidth designs, but for optimal designs in applications that require high radiofrequency power over a wide bandwidth, such as high-density communications or high-resolution radar, the variation of the circuit response with respect to frequency must be considered. This work at the NASA Glenn Research Center is the first to develop techniques for optimizing TWT efficiency and output power over a broad frequency bandwidth (ref. 2). The techniques are based on simulated annealing, which has the advantage over conventional optimization techniques in that it enables the best possible solution to be obtained (ref. 3). Two new broadband simulated annealing algorithms were developed that optimize (1) minimum saturated power efficiency over a frequency bandwidth and (2) simultaneous bandwidth and minimum power efficiency over the frequency band with constant input power. The algorithms were incorporated into the NASA coupled-cavity TWT computer model (ref. 4) and used to design optimal phase velocity tapers using the 59- to 64-GHz Hughes 961HA coupled-cavity TWT as a baseline model. In comparison to the baseline design, the computational results of the first broad-band design algorithm show an improvement of 73.9 percent in minimum saturated efficiency (see the top graph). The second broadband design algorithm (see the bottom graph) improves minimum radiofrequency efficiency with constant input power drive by a factor of 2.7 at the high band edge (64 GHz) and increases simultaneous bandwidth by 500 MHz.

  6. STICK INSECT CHEMICAL DEFENSES: POTENTIAL FOR USEFUL CHEMISTRY (ORDER PHASMATODEA)

    USDA-ARS?s Scientific Manuscript database

    Insects make up the most numerous and diverse group of organisms on the planet, yet make up one of the least explored groups of organisms in natural products research (Dossey, A. T., Nat. Prod Rep. 2010, 27, 1737–1757). For about five years our stick insect chemical defense research has led to sever...

  7. MolPrint3D: Enhanced 3D Printing of Ball-and-Stick Molecular Models

    ERIC Educational Resources Information Center

    Paukstelis, Paul J.

    2018-01-01

    The increased availability of noncommercial 3D printers has provided instructors and students improved access to printing technology. However, printing complex ball-and-stick molecular structures faces distinct challenges, including the need for support structures that increase with molecular complexity. MolPrint3D is a software add-on for the…

  8. Flight Control System Reliability and Maintainability Investigations

    DTIC Science & Technology

    1975-03-01

    the left forward horn of the swash - plate . Pilot’s Cyclic Control Stick The conventional type control stick, mounted in the ... the requirement? 3. Acceptability - Is the effort/cost worth the gain in R&M7 These tests were applied to the flight control system speci- fication...quantitative R&M requirements on the specifications in Figure 1. Standard Components

  9. Identifying Student Use of Ball-and-Stick Images versus Electrostatic Potential Map Images via Eye Tracking

    ERIC Educational Resources Information Center

    Williamson, Vickie M.; Hegarty, Mary; Deslongchamps, Ghislain; Williamson, Kenneth C., III

    2013-01-01

    This pilot study examined students' use of ball-and-stick images versus electrostatic potential maps when asked questions about electron density, positive charge, proton attack, and hydroxide attack with six different molecules (two alcohols, two carboxylic acids, and two hydroxycarboxylic acids). Students' viewing of these dual images…

  10. Effect of litter type upon fuel-moisture indicator stick values

    Treesearch

    W. L. Fons; C. M. Countryman

    1950-01-01

    Instructions for establishing fire-weather stations in Region 5 have usually specified that the fuel-moisture indicator sticks be placed over a bed of ponderosa pine needles. This specification was made to insure uniform ground-cover effect for all stations. Because ponderosa pine needles are not readily available in all areas of California fire control...

  11. "Sticking Together": The Adolescent Experience of the Cohesion Process in Rural School Counseling Groups

    ERIC Educational Resources Information Center

    Gray, Tara M.; Rubel, Deborah

    2018-01-01

    The purpose of this study was to develop a grounded theory of how adolescents experience the cohesion process in rural school counseling groups. A total of 20 individual interviews with 7 participants were conducted. Data analysis generated the central category of the cohesion process as "sticking together," which describes a "tight…

  12. 78 FR 76248 - Special Conditions: Airbus, Model A350-900 Series Airplane; Side Stick Controller

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-17

    ... control columns and wheels. This kind of controller is designed for only one-hand operation. The... same subject: For the Airbus Model A350-900 series airplane equipped with stick controls designed for... Airbus Model A350-900 series airplanes. These airplanes will have a novel or unusual design feature...

  13. D'Nealian Manuscript--An Aid to Reading Development.

    ERIC Educational Resources Information Center

    Thurber, Donald N.

    A new method of continuous stroke manuscript print called D'Nealian Manuscript is challenging the traditional circle-stick method of teaching children how to write. The circle-stick uses component or splinter parts to form whole letters. Children are forced to form all writing with verticle lines and to learn a manuscript print that goes nowhere.…

  14. Recognizing and Nurturing Hidden Creative Potential

    ERIC Educational Resources Information Center

    Connell, Elizabeth E.

    2010-01-01

    Peter, 7 years old, spends most of his time playing with his stick alone. After several unsuccessful attempts to get Peter to join his cousins, his aunt asks the boy's parents if they have considered having him evaluated by a psychologist. Peter's parents are not as concerned about the stick behavior as is his aunt. Although the attachment to his…

  15. Preschoolers' Acquisition of Novel Verbs in the Double Object Dative

    ERIC Educational Resources Information Center

    Arunachalam, Sudha

    2017-01-01

    Children have difficulty comprehending novel verbs in the double object dative (e.g., "Fred blicked the dog a stick") as compared to the prepositional dative (e.g., "Fred blicked a stick to the dog"). We explored this pattern with 3 and 4 year olds (N = 60). In Experiment 1, we replicated the documented difficulty with the…

  16. 78 FR 76736 - Special Conditions: Bombardier Inc., Models BD-500-1A10 and BD-500-1A11 Series Airplanes; Side...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-19

    ... operating conditions and configurations, whether normal or non-normal. 2. Pilot control authority: The... Series Airplanes; Side Stick Controllers: Pilot Strength, Pilot Control Authority, and Pilot Control... side stick controllers for pitch and roll control instead of conventional wheels and columns. The...

  17. 77 FR 69571 - Special Conditions: Embraer S.A., Model EMB-550 Airplane, Limit Pilot Forces for Sidestick Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-20

    ... wheel or stick controls, is not appropriate for a sidestick controller, because pilot forces are applied... Forces for Sidestick Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of... instead of a conventional wheel or control stick. This kind of controller is designed to be operated using...

  18. 78 FR 11554 - Special Conditions: Embraer S.A., Model EMB-550 Airplane, Limit Pilot Forces for Sidestick Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-19

    ... wheel or stick controls, is not appropriate for a sidestick controller, because pilot forces are applied... Pilot Forces for Sidestick Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final... conventional wheel or control stick. This kind of controller is designed to be operated using only one hand...

  19. Transport of Sputtered Carbon During Ground-Based Life Testing of Ion Thrusters

    NASA Technical Reports Server (NTRS)

    Marker, Colin L.; Clemons, Lucas A.; Banks, Bruce A.; Miller, Sharon; Snyder, Aaron; Hung, Ching-Cheh; Karniotis, Christina A.; Waters, Deborah L.

    2005-01-01

    High voltage, high power electron bombardment ion thrusters needed for deep space missions will be required to be operated for long durations in space as well as during ground laboratory life testing. Carbon based ion optics are being considered for such thrusters. The sputter deposition of carbon and arc vaporized carbon flakes from long duration operation of ion thrusters can result in deposition on insulating surfaces, causing them to become conducting. Because the sticking coefficient is less than one, secondary deposition needs to be considered to assure that shorting of critical components does not occur. The sticking coefficient for sputtered carbon and arc vaporized carbon is measured as well as directional ejection distribution data for carbon that does not stick upon first impact.

  20. Natural oils and waxes: studies on stick bases.

    PubMed

    Budai, Lívia; Antal, István; Klebovich, Imre; Budai, Marianna

    2012-01-01

    The objective of the present article was to examine the role of origin and quantity of selected natural oils and waxes in the determination of the thermal properties and hardness of stick bases. The natural oils and waxes selected for the study were sunflower, castor, jojoba, and coconut oils. The selected waxes were yellow beeswax, candelilla wax, and carnauba wax. The hardness of the formulations is a critical parameter from the aspect of their application. Hardness was characterized by the measurement of compression strength along with the softening point, the drop point, and differential scanning calorimetry (DSC). It can be concluded that coconut oil, jojoba oil, and carnauba wax have the greatest influence on the thermal parameters of stick bases.

  1. Stick-slip chaos in a mechanical oscillator with dry friction

    NASA Astrophysics Data System (ADS)

    Kousaka, Takuji; Asahara, Hiroyuki; Inaba, Naohiko

    2018-03-01

    This study analyzes a forced mechanical dynamical system with dry friction that can generate chaotic stick-slip vibrations. We find that the dynamics proposed by Yoshitake et al. [Trans. Jpn. Soc. Mech. Eng. C 61, 768 (1995)] can be expressed as a nonautonomous constraint differential equation owing to the static friction force. The object is constrained to the surface of a moving belt by a static friction force from when it sticks to the surface until the force on the object exceeds the maximal static friction force. We derive a 1D Poincaré return map from the constrained mechanical system, and prove numerically that this 1D map has an absolutely continuous invariant measure and a positive Lyapunov exponent, providing strong evidence for chaos.

  2. Efficiency analysis of diffusion on T-fractals in the sense of random walks.

    PubMed

    Peng, Junhao; Xu, Guoai

    2014-04-07

    Efficiently controlling the diffusion process is crucial in the study of diffusion problem in complex systems. In the sense of random walks with a single trap, mean trapping time (MTT) and mean diffusing time (MDT) are good measures of trapping efficiency and diffusion efficiency, respectively. They both vary with the location of the node. In this paper, we analyze the effects of node's location on trapping efficiency and diffusion efficiency of T-fractals measured by MTT and MDT. First, we provide methods to calculate the MTT for any target node and the MDT for any source node of T-fractals. The methods can also be used to calculate the mean first-passage time between any pair of nodes. Then, using the MTT and the MDT as the measure of trapping efficiency and diffusion efficiency, respectively, we compare the trapping efficiency and diffusion efficiency among all nodes of T-fractal and find the best (or worst) trapping sites and the best (or worst) diffusing sites. Our results show that the hub node of T-fractal is the best trapping site, but it is also the worst diffusing site; and that the three boundary nodes are the worst trapping sites, but they are also the best diffusing sites. Comparing the maximum of MTT and MDT with their minimums, we find that the maximum of MTT is almost 6 times of the minimum of MTT and the maximum of MDT is almost equal to the minimum for MDT. Thus, the location of target node has large effect on the trapping efficiency, but the location of source node almost has no effect on diffusion efficiency. We also simulate random walks on T-fractals, whose results are consistent with the derived results.

  3. A minimum data set of water quality parameters to assess and compare treatment efficiency of stormwater facilities.

    PubMed

    Ingvertsen, Simon Toft; Jensen, Marina Bergen; Magid, Jakob

    2011-01-01

    Urban stormwater runoff is often of poor quality, impacting aquatic ecosystems and limiting the use of stormwater runoff for recreational purposes. Several stormwater treatment facilities (STFs) are in operation or at the pilot testing stage, but their efficiencies are neither well documented nor easily compared due to the complex contaminant profile of stormwater and the highly variable runoff hydrograph. On the basis of a review of available data sets on urban stormwater quality and environmental contaminant behavior, we suggest a few carefully selected contaminant parameters (the minimum data set) to be obligatory when assessing and comparing the efficiency of STFs. Consistent use of the minimum data set in all future monitoring schemes for STFs will ensure broad-spectrum testing at low costs and strengthen comparability among facilities. The proposed minimum data set includes: (i) fine fraction of suspended solids (<63 μm), (ii) total concentrations of zinc and copper, (iii) total concentrations of phenanthrene, fluoranthene, and benzo(b,k)fluoranthene, and (iv) total concentrations of phosphorus and nitrogen. Indicator pathogens and other specific contaminants (i.e., chromium, pesticides, phenols) may be added if recreational or certain catchment-scale objectives are to be met. Issues that need further investigation have been identified during the iterative process of developing the minimum data set. by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  4. Speedup of minimum discontinuity phase unwrapping algorithm with a reference phase distribution

    NASA Astrophysics Data System (ADS)

    Liu, Yihang; Han, Yu; Li, Fengjiao; Zhang, Qican

    2018-06-01

    In three-dimensional (3D) shape measurement based on phase analysis, the phase analysis process usually produces a wrapped phase map ranging from - π to π with some 2 π discontinuities, and thus a phase unwrapping algorithm is necessary to recover the continuous and nature phase map from which 3D height distribution can be restored. Usually, the minimum discontinuity phase unwrapping algorithm can be used to solve many different kinds of phase unwrapping problems, but its main drawback is that it requires a large amount of computations and has low efficiency in searching for the improving loop within the phase's discontinuity area. To overcome this drawback, an improvement to speedup of the minimum discontinuity phase unwrapping algorithm by using the phase distribution on reference plane is proposed. In this improved algorithm, before the minimum discontinuity phase unwrapping algorithm is carried out to unwrap phase, an integer number K was calculated from the ratio of the wrapped phase to the nature phase on a reference plane. And then the jump counts of the unwrapped phase can be reduced by adding 2K π, so the efficiency of the minimum discontinuity phase unwrapping algorithm is significantly improved. Both simulated and experimental data results verify the feasibility of the proposed improved algorithm, and both of them clearly show that the algorithm works very well and has high efficiency.

  5. Minimum energy control and optimal-satisfactory control of Boolean control network

    NASA Astrophysics Data System (ADS)

    Li, Fangfei; Lu, Xiwen

    2013-12-01

    In the literatures, to transfer the Boolean control network from the initial state to the desired state, the expenditure of energy has been rarely considered. Motivated by this, this Letter investigates the minimum energy control and optimal-satisfactory control of Boolean control network. Based on the semi-tensor product of matrices and Floyd's algorithm, minimum energy, constrained minimum energy and optimal-satisfactory control design for Boolean control network are given respectively. A numerical example is presented to illustrate the efficiency of the obtained results.

  6. Minimum Error Bounded Efficient L1 Tracker with Occlusion Detection (PREPRINT)

    DTIC Science & Technology

    2011-01-01

    Minimum Error Bounded Efficient `1 Tracker with Occlusion Detection Xue Mei\\ ∗ Haibin Ling† Yi Wu†[ Erik Blasch‡ Li Bai] \\Assembly Test Technology...proposed BPR-L1 tracker is tested on several challenging benchmark sequences involving chal- lenges such as occlusion and illumination changes. In all...point method de - pends on the value of the regularization parameter λ. In the experiments, we found that the total number of PCG is a few hundred. The

  7. Investigation of alternative layouts for the supercritical carbon dioxide Brayton cycle for a sodium-cooled fast reactor.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moisseytsev, A.; Sienicki, J. J.

    2009-07-01

    Analyses of supercritical carbon dioxide (S-CO{sub 2}) Brayton cycle performance have largely settled on the recompression supercritical cycle (or Feher cycle) incorporating a flow split between the main compressor downstream of heat rejection, a recompressing compressor providing direct compression without heat rejection, and high and low temperature recuperators to raise the effectiveness of recuperation and the cycle efficiency. Alternative cycle layouts have been previously examined by Angelino (Politecnico, Milan), by MIT (Dostal, Hejzlar, and Driscoll), and possibly others but not for sodium-cooled fast reactors (SFRs) operating at relatively low core outlet temperature. Thus, the present authors could not be suremore » that the recompression cycle is an optimal arrangement for application to the SFR. To ensure that an advantageous alternative layout has not been overlooked, several alternative cycle layouts have been investigated for a S-CO{sub 2} Brayton cycle coupled to the Advanced Burner Test Reactor (ABTR) SFR preconceptual design having a 510 C core outlet temperature and a 470 C turbine inlet temperature to determine if they provide any benefit in cycle performance (e.g., enhanced cycle efficiency). No such benefits were identified, consistent with the previous examinations, such that attention was devoted to optimizing the recompression supercritical cycle. The effects of optimizing the cycle minimum temperature and pressure are investigated including minimum temperatures and/or pressures below the critical values. It is found that improvements in the cycle efficiency of 1% or greater relative to previous analyses which arbitrarily fixed the minimum temperature and pressure can be realized through an optimal choice of the combination of the minimum cycle temperature and pressure (e.g., for a fixed minimum temperature there is an optimal minimum pressure). However, this leads to a requirement for a larger cooler for heat rejection which may impact the tradeoff between efficiency and capital cost. In addition, for minimum temperatures below the critical temperature, a lower heat sink temperature is required the availability of which is dependent upon the climate at the specific plant site.« less

  8. Computationally-Efficient Minimum-Time Aircraft Routes in the Presence of Winds

    NASA Technical Reports Server (NTRS)

    Jardin, Matthew R.

    2004-01-01

    A computationally efficient algorithm for minimizing the flight time of an aircraft in a variable wind field has been invented. The algorithm, referred to as Neighboring Optimal Wind Routing (NOWR), is based upon neighboring-optimal-control (NOC) concepts and achieves minimum-time paths by adjusting aircraft heading according to wind conditions at an arbitrary number of wind measurement points along the flight route. The NOWR algorithm may either be used in a fast-time mode to compute minimum- time routes prior to flight, or may be used in a feedback mode to adjust aircraft heading in real-time. By traveling minimum-time routes instead of direct great-circle (direct) routes, flights across the United States can save an average of about 7 minutes, and as much as one hour of flight time during periods of strong jet-stream winds. The neighboring optimal routes computed via the NOWR technique have been shown to be within 1.5 percent of the absolute minimum-time routes for flights across the continental United States. On a typical 450-MHz Sun Ultra workstation, the NOWR algorithm produces complete minimum-time routes in less than 40 milliseconds. This corresponds to a rate of 25 optimal routes per second. The closest comparable optimization technique runs approximately 10 times slower. Airlines currently use various trial-and-error search techniques to determine which of a set of commonly traveled routes will minimize flight time. These algorithms are too computationally expensive for use in real-time systems, or in systems where many optimal routes need to be computed in a short amount of time. Instead of operating in real-time, airlines will typically plan a trajectory several hours in advance using wind forecasts. If winds change significantly from forecasts, the resulting flights will no longer be minimum-time. The need for a computationally efficient wind-optimal routing algorithm is even greater in the case of new air-traffic-control automation concepts. For air-traffic-control automation, thousands of wind-optimal routes may need to be computed and checked for conflicts in just a few minutes. These factors motivated the need for a more efficient wind-optimal routing algorithm.

  9. Estimate of Cost-Effective Potential for Minimum Efficiency Performance Standards in 13 Major World Economies Energy Savings, Environmental and Financial Impacts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Letschert, Virginie E.; Bojda, Nicholas; Ke, Jing

    2012-07-01

    This study analyzes the financial impacts on consumers of minimum efficiency performance standards (MEPS) for appliances that could be implemented in 13 major economies around the world. We use the Bottom-Up Energy Analysis System (BUENAS), developed at Lawrence Berkeley National Laboratory (LBNL), to analyze various appliance efficiency target levels to estimate the net present value (NPV) of policies designed to provide maximum energy savings while not penalizing consumers financially. These policies constitute what we call the “cost-effective potential” (CEP) scenario. The CEP scenario is designed to answer the question: How high can we raise the efficiency bar in mandatory programsmore » while still saving consumers money?« less

  10. Learning a stick-balancing task involves task-specific coupling between posture and hand displacements.

    PubMed

    Cluff, Tyler; Boulet, Jason; Balasubramaniam, Ramesh

    2011-08-01

    Theories of motor learning argue that the acquisition of novel motor skills requires a task-specific organization of sensory and motor subsystems. We examined task-specific coupling between motor subsystems as subjects learned a novel stick-balancing task. We focused on learning-induced changes in finger movements and body sway and investigated the effect of practice on their coupling. Eight subjects practiced balancing a cylindrical wooden stick for 30 min a day during a 20 day learning period. Finger movements and center of pressure trajectories were recorded in every fifth practice session (4 in total) using a ten camera VICON motion capture system interfaced with two force platforms. Motor learning was quantified using average balancing trial lengths, which increased with practice and confirmed that subjects learned the task. Nonlinear time series and phase space reconstruction methods were subsequently used to investigate changes in the spatiotemporal properties of finger movements, body sway and their progressive coupling. Systematic increases in subsystem coupling were observed despite reduced autocorrelation and differences in the temporal properties of center of pressure and finger trajectories. The average duration of these coupled trajectories increased systematically across the learning period. In short, the abrupt transition between coupled and decoupled subsystem dynamics suggested that stick balancing is regulated by a hierarchical control mechanism that switches from collective to independent control of the finger and center of pressure. In addition to traditional measures of motor performance, dynamical analyses revealed changes in motor subsystem organization that occurred when subjects learned a novel stick-balancing task.

  11. The Prevalence of Olfactory Dysfunction in Chronic Rhinosinusitis

    PubMed Central

    Kohli, Preeti; Naik, Akash N.; Harruff, E. Emily; Nguyen, Shaun A.; Schlosser, Rodney J.; Soler, Zachary M.

    2016-01-01

    Objective Many studies have reported that olfactory dysfunction frequently occurs in chronic rhinosinusitis (CRS) populations; however, the prevalence and degree of olfactory loss has not been systematically studied. The aims of this study are to use combined data to report the prevalence of olfactory dysfunction and to calculate weighted averages of olfactory test scores in CRS patients. Data Sources A search was conducted in PubMed and Scopus, following the methods of Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Review Methods Studies reporting the prevalence of olfactory dysfunction using objective measures or olfactory test scores using validated scales were included. Results A total of 47 articles were included in systematic review and 35 in the pooled data analysis. The prevalence of olfactory dysfunction in chronic rhinosinusitis was found to be 30.0% using the Brief Smell Identification Test, 67.0% using the 40-item Smell Identification Test, and 78.2% using the total Sniffin’ Sticks score. Weighted averages ± standard deviation of olfactory test scores were 25.96±7.11 using the 40-item Smell Identification Test, 8.60±2.81 using the Brief Smell Identification Test, 21.96±8.88 using total Sniffin’ sticks score, 5.65±1.51 using Sniffin’ Sticks threshold, 9.21±4.63 using Sniffin’ Sticks discrimination, 9.47±3.92 using Sniffin’ Sticks Identification, and 8.90±5.14 using the questionnaire for olfactory disorders-negative statements. Conclusion In chronic rhinosinusitis populations, a significant percentage of patients experience olfactory dysfunction and mean olfactory scores are within the dysosmic range. PMID:27873345

  12. The Impact of Frictional Healing on Stick-Slip Recurrence Interval and Stress Drop: Implications for Earthquake Scaling

    NASA Astrophysics Data System (ADS)

    Im, Kyungjae; Elsworth, Derek; Marone, Chris; Leeman, John

    2017-12-01

    Interseismic frictional healing is an essential process in the seismic cycle. Observations of both natural and laboratory earthquakes demonstrate that the magnitude of stress drop scales with the logarithm of recurrence time, which is a cornerstone of the rate and state friction (RSF) laws. However, the origin of this log linear behavior and short time "cutoff" for small recurrence intervals remains poorly understood. Here we use RSF laws to demonstrate that the back-projected time of null-healing intrinsically scales with the initial frictional state θi. We explore this behavior and its implications for (1) the short-term cutoff time of frictional healing and (2) the connection between healing rates derived from stick-slip sliding versus slide-hold-slide tests. We use a novel, continuous solution of RSF for a one-dimensional spring-slider system with inertia. The numerical solution continuously traces frictional state evolution (and healing) and shows that stick-slip cutoff time also scales with frictional state at the conclusion of the dynamic slip process θi (=Dc/Vpeak). This numerical investigation on the origins of stick-slip response is verified by comparing laboratory data for a range of peak slip velocities. Slower slip motions yield lesser magnitude of friction drop at a given time due to higher frictional state at the end of each slip event. Our results provide insight on the origin of log linear stick-slip evolution and suggest an approach to estimating the critical slip distance on faults that exhibit gradual accelerations, such as for slow earthquakes.

  13. Determination of histamine in milkfish stick implicated in food-borne poisoning.

    PubMed

    Lee, Yi-Chen; Kung, Hsien-Feng; Wu, Chien-Hui; Hsu, Hui-Mei; Chen, Hwi-Chang; Huang, Tzou-Chi; Tsai, Yung-Hsiang

    2016-01-01

    An incident of food-borne poisoning causing illness in 37 victims due to ingestion of fried fish sticks occurred in September 2014, in Tainan city, southern Taiwan. Leftovers of the victims' fried fish sticks and 16 other raw fish stick samples from retail stores were collected and tested to determine the occurrence of histamine and histamine-forming bacteria. Two suspected fried fish samples contained 86.6 mg/100 g and 235.0 mg/100 g histamine; levels that are greater than the potential hazard action level (50 mg/100 g) in most illness cases. Given the allergy-like symptoms of the victims and the high histamine content in the suspected fried fish samples, this food-borne poisoning was strongly suspected to be caused by histamine intoxication. Moreover, the fish species of suspected samples was identified as milkfish (Chanos chanos), using polymerase chain reaction direct sequence analysis. In addition, four of the 16 commercial raw milkfish stick samples (25%) had histamine levels greater than the US Food & Drug Administration guideline of 5.0 mg/100 g for scombroid fish and/or products. Ten histamine-producing bacterial strains, capable of producing 373-1261 ppm of histamine in trypticase soy broth supplemented with 1.0% L-histidine, were identified as Enterobacter aerogenes (4 strains), Enterobacter cloacae (1 strain), Morganella morganii (2 strains), Serratia marcescens (1 strain), Hafnia alvei (1 strain), and Raoultella orithinolytica (1 strain), by 16S ribosomal DNA sequencing with polymerase chain reaction amplification. Copyright © 2015. Published by Elsevier B.V.

  14. Integration of a vision-based tracking platform, visual instruction, and error analysis models for an efficient billiard training system

    NASA Astrophysics Data System (ADS)

    Shih, Chihhsiong; Hsiung, Pao-Ann; Wan, Chieh-Hao; Koong, Chorng-Shiuh; Liu, Tang-Kun; Yang, Yuanfan; Lin, Chu-Hsing; Chu, William Cheng-Chung

    2009-02-01

    A billiard ball tracking system is designed to combine with a visual guide interface to instruct users for a reliable strike. The integrated system runs on a PC platform. The system makes use of a vision system for cue ball, object ball and cue stick tracking. A least-squares error calibration process correlates the real-world and the virtual-world pool ball coordinates for a precise guidance line calculation. Users are able to adjust the cue stick on the pool table according to a visual guidance line instruction displayed on a PC monitor. The ideal visual guidance line extended from the cue ball is calculated based on a collision motion analysis. In addition to calculating the ideal visual guide, the factors influencing selection of the best shot among different object balls and pockets are explored. It is found that a tolerance angle around the ideal line for the object ball to roll into a pocket determines the difficulty of a strike. This angle depends in turn on the distance from the pocket to the object, the distance from the object to the cue ball, and the angle between these two vectors. Simulation results for tolerance angles as a function of these quantities are given. A selected object ball was tested extensively with respect to various geometrical parameters with and without using our integrated system. Players with different proficiency levels were selected for the experiment. The results indicate that all players benefit from our proposed visual guidance system in enhancing their skills, while low-skill players show the maximum enhancement in skill with the help of our system. All exhibit enhanced maximum and average hit-in rates. Experimental results on hit-in rates have shown a pattern consistent with that of the analysis. The hit-in rate is thus tightly connected with the analyzed tolerance angles for sinking object balls into a target pocket. These results prove the efficiency of our system, and the analysis results can be used to attain an efficient game-playing strategy.

  15. Muon Catalyzed Fusion in Solid Hydrogen

    NASA Astrophysics Data System (ADS)

    Marshall, Glen

    1998-04-01

    The mass, lifetime, and leptonic nature of the negative muon allow it to induce repeated fusion reactions between nuclei of hydrogen isotopes. The processes by which this takes place encompass nuclear as well as atomic and molecular interactions, both normal and exotic, with energy scales from meV to MeV. It has taken several decades to disentangle the important aspects and understand quantitatively what limitations exist on efficient catalysis of fusion. The two major limitations are the rates at which muonic molecular ions can be formed, and the small but critical probability that the muon becomes attached to a charged fusion product in the process known as sticking. Extensive theoretical work has resulted in a detailed understanding of both, and experimental efforts have contributed significant insight. There are unique experimental advantages to using solid hydrogen in the form of inhomogeneous layered targets. Non-thermalized muonic hydrogen atoms allow us to explore resonant molecular ion formation processes near eV kinetic energies. Isotopically specific layers make it possible to separate competing and confusing interactions. Unambiguous charged fusion product detection is simplified and complements the more conventional detection of fusion neutrons. Experiments with negative muons in solid hydrogen can help to understand the limitations of both the molecular ion formation rate and the sticking probability. The processes of importance will be described, followed by a discussion of recent results and possibilities for the future.

  16. [Tetanus risk assessment in the older outpatients: Usefulness of the "Tétanos Quick Stick ®"?].

    PubMed

    Nicolaï, D; Farcet, A; Molines, C; Delalande, G; Retornaz, F

    2015-05-01

    Tetanus is a serious disease, which could be potentially lethal. All cases are observed in patients inadequately immunized. The immunochromatographic tests (including Tetanos quick Stick(®) [TQS]) have demonstrated their efficiency in emergency setting. The aim of our study was to assess the usefulness of these tests in elderly outpatients seen in ambulatory settings. This prospective study included patients aged 65 years and over who presented to the outpatients' clinic of the Gerontologic Departmental Center (Marseille). A TQS and a self-administered questionnaire to assess risk factors for tetanus were performed. One hundred and twenty-two patients were studied. The prevalence of positive TQS was 66%. Patients have an average of 2.5 risk factors for tetanus. Negative TQS was observed in 35% of patients who had seen their general practitioner for a wound during the previous year. Elderly patients accumulate several risk factors regardless of age and lifestyle. While physicians are familiar with the vaccine recommendations, they are often faced with the difficulty of assessing patient's status based only on the patient's interview, which is frequently not reliable. The implementation of immunochromatographic tests in general practice could help physicians in the management of patients at risk for tetanus. Copyright © 2014 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  17. Estimating the fuel moisture content of indicator sticks from selected weather variables

    Treesearch

    Theodore G. Storey

    1965-01-01

    Equations were developed to predict the fuel moisture content of indicator sticks from the controlling weather variables. Moisture content of ⅛-inch thick basswood slats used in the South and East could be determined with about equal precision by equation in the critical low moisture range or by weighing at fire danger stations. The most useful equation...

  18. 50 CFR 660.705 - Prohibitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Possess a light stick on board a longline vessel when fishing west of 150° W. long. and north of the... longline gear north of 23° N. lat. in violation of § 660.712 (c)(1)(iii). (z) Fail to maintain and use blue... fishing under a western Pacific longline limited entry permit issued under § 660.21, possess a light stick...

  19. 50 CFR 660.705 - Prohibitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) Possess a light stick on board a longline vessel when fishing west of 150° W. long. and north of the.... in violation of § 660.712 (c)(1)(iii). (z) Fail to maintain and use blue dye to prepare thawed bait... permit issued under § 660.21, possess a light stick on board a longline vessel on the high seas of the...

  20. 50 CFR 660.705 - Prohibitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) Possess a light stick on board a longline vessel when fishing west of 150° W. long. and north of the.... in violation of § 660.712 (c)(1)(iii). (z) Fail to maintain and use blue dye to prepare thawed bait... permit issued under § 660.21, possess a light stick on board a longline vessel on the high seas of the...

  1. 50 CFR 660.705 - Prohibitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) Possess a light stick on board a longline vessel when fishing west of 150° W. long. and north of the.... in violation of § 660.712 (c)(1)(iii). (z) Fail to maintain and use blue dye to prepare thawed bait... permit issued under § 660.21, possess a light stick on board a longline vessel on the high seas of the...

  2. The Use of Fry (Embalming Fluid and PCP-Laced Cigarettes or Marijuana Sticks) among Crack Cocaine Smokers

    ERIC Educational Resources Information Center

    Peters, Ronald J.; Williams, Mark; Ross, Michael W.; Atkinson, John; McCurdy, Sherly A.

    2009-01-01

    Statistics show that the prevalence of crack cocaine use and embalming fluid and phencyclidine (PCP)-laced cigarettes or marijuana sticks, commonly referred to on the street as "fry" or "wet" is a problem; however, the relationship between these substances of abuse and concurrent polydrug use is unknown. In the present study, a…

  3. Entering First-Year Residents' Experiences and Knowledge of Infection Control of Hepatitis B and HIV, at Five University-Affiliated Hospitals.

    ERIC Educational Resources Information Center

    Goetz, Angella; And Others

    1992-01-01

    A survey of 149 entering first-year medical residents concerning experiences with and knowledge of infection control investigated occurrence and patterns of accidental needle-sticking and reporting, student immunization for Hepatitis B, and instruction in universal precautions. It is concluded that students are at risk for needle-sticking, but…

  4. Neither a Toddler nor a Stick-in-the-Mud

    ERIC Educational Resources Information Center

    Smith, Andrea Livi

    2011-01-01

    The goal of this paper is to express the views from the "outside," from laypeople who want to go to museums, but perhaps find themselves not going very often. Adult visitors to history museums are often treated as either toddlers or sticks-in-the-mud, where they are assumed to break anything they touch, or enjoy didactic lectures. As a result,…

  5. Air Combat Training: Good Stick Index Validation. Final Report for Period 3 April 1978-1 April 1979.

    ERIC Educational Resources Information Center

    Moore, Samuel B.; And Others

    A study was conducted to investigate and statistically validate a performance measuring system (the Good Stick Index) in the Tactical Air Command Combat Engagement Simulator I (TAC ACES I) Air Combat Maneuvering (ACM) training program. The study utilized a twelve-week sample of eighty-nine student pilots to statistically validate the Good Stick…

  6. Method for preventing micromechanical structures from adhering to another object

    DOEpatents

    Smith, James H.; Ricco, Antonio J.

    1998-01-01

    A method for preventing micromechanical structures from adhering to another object includes the step of immersing a micromechanical structure and its associated substrate in a chemical species that does not stick to itself. The method can be employed during the manufacture of micromechanical structures to prevent micromechanical parts from sticking or adhering to one another and their associated substrate surface.

  7. Kick Stick Hands-on Challenge: Discover Circuits with PBS's "Design Squad Nation"[TM

    ERIC Educational Resources Information Center

    Feinberg, Lauren

    2011-01-01

    This article describes the "Kick Stick" activity from Design Squad Nation, in which kids turn a wooden paint stirrer and circuit into a motorized, spinning arm--then use it to kick a Ping-Pong[R] ball across the floor. Teachers can enrich their students' exploration of circuits and emphasize the engineering design process with "Design Squad…

  8. Impact of Religion on Turkish Early Childhood Teachers' Factuality Judgments and Their Classroom Practice

    ERIC Educational Resources Information Center

    Kotaman, Hüseyin

    2016-01-01

    The purpose of this study is to examine the impact of religion on Turkish early childhood teachers' factuality judgments and reasoning. Participants responded following questions about the story of "Moses's stick": 1) Can Moses run water from a dry fountain just by hitting his stick to the ground? 2) Why, or why not? 3) Would you read…

  9. Innovation That Sticks Case Study Report: Ottawa Catholic School Board. Leading and Learning for Innovation, A Framework for District-Wide Change

    ERIC Educational Resources Information Center

    Canadian Education Association, 2016

    2016-01-01

    A Canadian Education Association (CEA) Selection Jury chose the Ottawa Catholic School Board (OCSB) out of 35 School District applicants from across Canada to participate in the 2015 "Innovation that Sticks" Case Study Program. From September to December 2015--through an Appreciative Inquiry interview process--the CEA researched how the…

  10. Boll weevil (Coleoptera: Curculionidae) bait sticks: Toxicity and malathion content

    Treesearch

    Eric J. Villavaso; Joseph E. Mulrooney; William L. Mcgovern

    2003-01-01

    Assays of malathion content and toxicity to boll weevil, Anll~onorni~gsr andis granrlis Boheman, were conducted on boll weevil bait sticks, now marketed as Boll Weevil Attract ancl Control Tubes (BWACTs: Plato Industries, Houston, TX). In general. the longer BWACTs were in the field, the lower the mortality of weevils that were exposed to them. Bioassays of weevil...

  11. Hubble's Hockey Stick Galaxy

    NASA Image and Video Library

    2017-12-08

    The star of this NASA/ESA Hubble Space Telescope image is a galaxy known as NGC 4656, located in the constellation of Canes Venatici (The Hunting Dogs). However, it also has a somewhat more interesting and intriguing name: the Hockey Stick Galaxy! The reason for this is a little unclear from this partial view, which shows the bright central region, but the galaxy is actually shaped like an elongated, warped stick, stretching out through space until it curls around at one end to form a striking imitation of a celestial hockey stick. This unusual shape is thought to be due to an interaction between NGC 4656 and a couple of near neighbors, NGC 4631 (otherwise known as The Whale Galaxy) and NGC 4627 (a small elliptical). Galactic interactions can completely reshape a celestial object, shifting and warping its constituent gas, stars, and dust into bizarre and beautiful configurations. Credit: ESA/Hubble & NASA NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  12. Modeling Pilot Pulse Control

    NASA Technical Reports Server (NTRS)

    Bachelder, Edward; Hess, Ronald; Godfroy-Cooper, Martine; Aponso, Bimal

    2017-01-01

    In this study, behavioral models are developed that closely reproduced pulsive control response of two pilots from the experimental pool using markedly different control techniques (styles) while conducting a tracking task. An intriguing find was that the pilots appeared to: 1) produce a continuous, internally-generated stick signal that they integrated in time; 2) integrate the actual stick position; and 3) compare the two integrations to issue and cease pulse commands. This suggests that the pilots utilized kinesthetic feedback in order to perceive and integrate stick position, supporting the hypothesis that pilots can access and employ the proprioceptive inner feedback loop proposed by Hess' pilot Structural Model. The Pulse Models used in conjunction with the pilot Structural Model closely recreated the pilot data both in the frequency and time domains during closed-loop simulation. This indicates that for the range of tasks and control styles encountered, the models captured the fundamental mechanisms governing pulsive and control processes. The pilot Pulse Models give important insight for the amount of remnant (stick output uncorrelated with the forcing function) that arises from nonlinear pilot technique, and for the remaining remnant arising from different sources unrelated to tracking control (i.e. neuromuscular tremor, reallocation of cognitive resources, etc.).

  13. Deriving neural network controllers from neuro-biological data: implementation of a single-leg stick insect controller.

    PubMed

    von Twickel, Arndt; Büschges, Ansgar; Pasemann, Frank

    2011-02-01

    This article presents modular recurrent neural network controllers for single legs of a biomimetic six-legged robot equipped with standard DC motors. Following arguments of Ekeberg et al. (Arthropod Struct Dev 33:287-300, 2004), completely decentralized and sensori-driven neuro-controllers were derived from neuro-biological data of stick-insects. Parameters of the controllers were either hand-tuned or optimized by an evolutionary algorithm. Employing identical controller structures, qualitatively similar behaviors were achieved for robot and for stick insect simulations. For a wide range of perturbing conditions, as for instance changing ground height or up- and downhill walking, swing as well as stance control were shown to be robust. Behavioral adaptations, like varying locomotion speeds, could be achieved by changes in neural parameters as well as by a mechanical coupling to the environment. To a large extent the simulated walking behavior matched biological data. For example, this was the case for body support force profiles and swing trajectories under varying ground heights. The results suggest that the single-leg controllers are suitable as modules for hexapod controllers, and they might therefore bridge morphological- and behavioral-based approaches to stick insect locomotion control.

  14. Molecular origin of contact line stick-slip motion during droplet evaporation

    PubMed Central

    Wang, FengChao; Wu, HengAn

    2015-01-01

    Understanding and controlling the motion of the contact line is of critical importance for surface science studies as well as many industrial engineering applications. In this work, we elucidate the molecular origin of contact line stick-slip motion during the evaporation of liquid droplets on flexible nano-pillared surfaces using molecular dynamics simulations. We demonstrate that the evaporation-induced stick-slip motion of the contact line is a consequence of competition between pinning and depinning forces. Furthermore, the tangential force exerted by the pillared substrate on the contact line was observed to have a sawtooth-like oscillation. Our analysis also establishes that variations in the pinning force are accomplished through the self-adaptation of solid-liquid intermolecular distances, especially for liquid molecules sitting directly on top of the solid pillar. Consistent with our theoretical analysis, molecular dynamics simulations also show that the maximum pinning force is quantitatively related to both solid-liquid adhesion strength and liquid-vapor surface tension. These observations provide a fundamental understanding of contact line stick-slip motion on pillared substrates and also give insight into the microscopic interpretations of contact angle hysteresis, wetting transitions and dynamic spreading. PMID:26628084

  15. Biofuel from jute stick by pyrolysis technology

    NASA Astrophysics Data System (ADS)

    Ferdous, J.; Parveen, M.; Islam, M. R.; Haniu, H.; Takai, K.

    2017-06-01

    In this study the conversion of jute stick into biofuels and chemicals by externally heated fixed-bed pyrolysis reactor have been taken into consideration. The solid jute stick was characterized through proximate and ultimate analysis, gross calorific values and thermo-gravimetric analysis to investigate their suitability as feedstock for this consideration. The solid biomass particles were fed into the reactor by gravity feed type reactor feeder. The products were oil, char and gases. The liquid and char products were collected separately while the gas was flared into the atmosphere. The process conditions were varied by fixed-bed temperature; feed stock particle size, N2 gas flow rate and running time. All parameters were found to influence the product yields significantly. The maximum liquid yields were 50 wt% of solid jute stick at reactor temperature 425°C for N2 gas flow rate 6 l/min, feed particle size 1180-1700 µm and running time 30 min. Liquid products obtained at these conditions were characterized by physical properties, chemical analysis and GC-MS techniques. The results show that it is possible to obtained liquid products that are comparable to petroleum fuels and valuable chemical feedstock from the selected biomass if the pyrolysis conditions are chosen accordingly.

  16. Micro transflection on a metallic stick: an innovative approach of reflection infrared spectroscopy for minimally invasive investigation of painting varnishes.

    PubMed

    Rosi, Francesca; Legan, Lea; Miliani, Costanza; Ropret, Polonca

    2017-05-01

    A new analytical approach, based on micro-transflection measurements from a diamond-coated metal sampling stick, is presented for the analysis of painting varnishes. Minimally invasive sampling is performed from the varnished surface using the stick, which is directly used as a transflection substrate for micro Fourier transform infrared (FTIR) measurements. With use of a series of varnished model paints, the micro-transflection method has been proved to be a valuable tool for the identification of surface components thanks to the selectivity of the sampling, the enhancement of the absorbance signal, and the easier spectral interpretation because the profiles are similar to transmission mode ones. Driven by these positive outcomes, the method was then tested as tool supporting noninvasive reflection FTIR spectroscopy during the assessment of varnish removal by solvent cleaning on paint models. Finally, the integrated analytical approach based on the two reflection methods was successfully applied for the monitoring of the cleaning of the sixteenth century painting Presentation in the Temple by Vittore Carpaccio. Graphical Abstract Micro-transflection FTIR on a metallic stick for the identification of varnishes during painting cleanings.

  17. Agatharesinol biosynthesis-related changes of ray parenchyma in sapwood sticks of Cryptomeria japonica during cell death.

    PubMed

    Nakaba, Satoshi; Arakawa, Izumi; Morimoto, Hikaru; Nakada, Ryogo; Bito, Nobumasa; Imai, Takanori; Funada, Ryo

    2016-05-01

    The work demonstrates a relationship between the biosynthesis of the secondary metabolite, agatharesinol, and cytological changes that occur in ray parenchyma during cell death in sapwood sticks of Cryptomeria japonica under humidity-regulated conditions. To characterize the death of ray parenchyma cells that accompanies the biosynthesis of secondary metabolites, we examined cell death in sapwood sticks of Cryptomeria japonica under humidity-regulated conditions. We monitored features of ray parenchyma cells, such as viability, the morphology of nuclei and vacuoles, and the amount of starch grains. In addition, we analyzed levels of agatharesinol, a heartwood norlignan, by gas chromatography-mass spectrometry in the same sapwood sticks. Dramatic changes in the amount of starch grains and in the level of agatharesinol occurred simultaneously. Therefore, the biosynthesis of agatharesinol appeared to originate from the breakdown of starch. Furthermore, we observed the expansion of vacuoles in ray parenchyma cells prior to other cytological changes at the final stage of cell death. In our experimental system, we were able to follow the process of cell death and to demonstrate relationships between cytological changes and the biosynthesis of a secondary metabolite during the death of ray parenchyma cells.

  18. Response coding and visuomotor transformation in the Simon task: the role of action goals.

    PubMed

    Buhlmann, Ivonne; Umiltà, Carlo; Wascher, Edmund

    2007-12-01

    Manual responses can be defined by differing response parameters. Any of them may generate a Simon effect. For all those response parameters, the same implementation of the Simon effect (in terms of subserving mechanism) is assumed. In 3 experiments, subjects had to respond with either fingers or sticks. Temporal properties of the Simon effect changed with response parameters relevant in a task. The Simon effect for manual responses decayed. For stick responses, in which the action goal differed from the anatomical mapping of the acting hand, a sustained Simon effect was observed. However, if the action goal for stick responses was not instrumental for selecting the correct response, the Simon effect decayed. The findings are consistent with the notion of different mechanisms involved in generating a Simon effect.

  19. Computer simulation on the collision-sticking dynamics of two colloidal particles in an optical trap.

    PubMed

    Xu, Shenghua; Sun, Zhiwei

    2007-04-14

    Collisions of a particle pair induced by optical tweezers have been employed to study colloidal stability. In order to deepen insights regarding the collision-sticking dynamics of a particle pair in the optical trap that were observed in experimental approaches at the particle level, the authors carry out a Brownian dynamics simulation. In the simulation, various contributing factors, including the Derjaguin-Landau-Verwey-Overbeek interaction of particles, hydrodynamic interactions, optical trapping forces on the two particles, and the Brownian motion, were all taken into account. The simulation reproduces the tendencies of the accumulated sticking probability during the trapping duration for the trapped particle pair described in our previous study and provides an explanation for why the two entangled particles in the trap experience two different statuses.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lieou, Charles K. C.; Daub, Eric G.; Guyer, Robert A.

    In this paper, we model laboratory earthquakes in a biaxial shear apparatus using the Shear-Transformation-Zone (STZ) theory of dense granular flow. The theory is based on the observation that slip events in a granular layer are attributed to grain rearrangement at soft spots called STZs, which can be characterized according to principles of statistical physics. We model lab data on granular shear using STZ theory and document direct connections between the STZ approach and rate-and-state friction. We discuss the stability transition from stable shear to stick-slip failure and show that stick slip is predicted by STZ when the applied shearmore » load exceeds a threshold value that is modulated by elastic stiffness and frictional rheology. Finally, we also show that STZ theory mimics fault zone dilation during the stick phase, consistent with lab observations.« less

  1. Relationship between the frequency magnitude distribution and the visibility graph in the synthetic seismicity generated by a simple stick-slip system with asperities.

    PubMed

    Telesca, Luciano; Lovallo, Michele; Ramirez-Rojas, Alejandro; Flores-Marquez, Leticia

    2014-01-01

    By using the method of the visibility graph (VG) the synthetic seismicity generated by a simple stick-slip system with asperities is analysed. The stick-slip system mimics the interaction between tectonic plates, whose asperities are given by sandpapers of different granularity degrees. The VG properties of the seismic sequences have been put in relationship with the typical seismological parameter, the b-value of the Gutenberg-Richter law. Between the b-value of the synthetic seismicity and the slope of the least square line fitting the k-M plot (relationship between the magnitude M of each synthetic event and its connectivity degree k) a close linear relationship is found, also verified by real seismicity.

  2. Analysis of Handling Qualities Design Criteria for Active Inceptor Force-Feel Characteristics

    NASA Technical Reports Server (NTRS)

    Malpica, Carlos A.; Lusardi, Jeff A.

    2013-01-01

    The force-feel system characteristics of the cyclic inceptors of most helicopters are set based on the characteristics of the mechanical components in the control system (mass, springs, friction dampers, etc.). For these helicopters, the force-feel characteristics typically remain constant over the entire flight envelope, with perhaps a trim release to minimize control forces while maneuvering. With the advent of fly-by-wire control systems and active inceptors in helicopters, the force-feel characteristics are now determined by the closed-loop response of the active inceptor itself as defined by the inertia, force/displacement gradient, damping, breakout force and detent shape configuration parameters in the inceptor control laws. These systems give the flexibility to dynamically prescribe different feel characteristics for different control modes or flight conditions, and the ability to provide tactile cueing to the pilot through the actively controlled side-stick or center-stick cyclic inceptor. For rotorcraft, a few studies have been conducted to assess the effects of cyclic force-feel characteristics on handling qualities in flight. An early study provided valuable insight into the static force-deflection characteristics (force gradient) and the number of axes controlled by the side-stick controller for the U.S. Army's Advanced Digital/Optical Control System (ADOCS) demonstrator aircraft [1]. The first of a series of studies providing insight on the inceptor dynamic force-feel characteristics was conducted on the NASA/Army CH-47B variable-stability helicopter [2]. This work led to a proposed requirement that set boundaries based on the cyclic natural frequency and inertia, with the stipulation of a lower damping ratio limit of 0.3 [3]. A second study was conducted by the Canadian Institute for Aerospace Research using their variable-stability Bell 205A helicopter [4]. This research suggested boundaries for stick dynamics based on natural frequency and damping ratio. While these two studies produced boundaries for acceptable/unacceptable stick dynamics for rotorcraft, they were not able to provide guidance on how variations of the stick dynamics in the acceptable region impact handling qualities. More recently, a ground based simulation study [5] suggested little benefit was to be obtained from variations of the damping ratio for a side-stick controller exhibiting high natural frequencies (greater than 17 rad/s) and damping ratios (greater than 2.0). A flight test campaign was conducted concurrently on the RASCAL JUH-60A in-flight simulator and the ACT/FHS EC-135 in flight simulator [6]. Upon detailed analysis of the pilot evaluations the study identified a clear preference for a high damping ratio and natural frequency of the center stick inceptors. Side stick controllers were found to be less sensitive to the damping. While these studies have compiled a substantial amount of data, in the form of qualitative and quantitative pilot opinion, a fundamental analysis of the effect of the inceptor force-feel system on flight control is found to be lacking. The study of Ref. [6] specifically concluded that a systematic analysis was necessary, since discrepancies with the assigned handling qualities showed that proposed analytical design metrics, or criteria, were not suitable. The overall goal of the present study is to develop a clearer fundamental understanding of the underlying mechanisms associated with the inceptor dynamics that govern the handling qualities using a manageable analytical methodology.

  3. High-voltage spark carbon-fiber sticky-tape data analyzer

    NASA Technical Reports Server (NTRS)

    Yang, L. C.; Hull, G. G.

    1980-01-01

    An efficient method for detecting carbon fibers collected on a stick tape monitor was developed. The fibers were released from a simulated crash fire situation containing carbon fiber composite material. The method utilized the ability of the fiber to initiate a spark across a set of alternately biased high voltage electrodes to electronically count the number of fiber fragments collected on the tape. It was found that the spark, which contains high energy and is of very short duration, is capable of partially damaging or consuming the fiber fragments. It also creates a mechanical disturbance which ejects the fiber from the grid. Both characteristics were helpful in establishing a single discharge pulse for each fiber segment.

  4. The volume- and surface-binding energies of ice systems containing CO, CO2, and H2O

    NASA Technical Reports Server (NTRS)

    Sandford, Scott A.; Allamandola, Louis J.

    1990-01-01

    Laboratory-measured, temperature-dependent sticking efficiencies are presently used to derive the surface-binding energies of CO and CO2 on H2O-rich ices, with a view to determining the condensation and vaporization properties of these systems as well as to the measured energies' implications for both cometary behavior and the evolution of interstellar ices. The molecular volume and the surface binding energies are not found to be necessarily related on the basis of simple nearest-neighbor scaling in surface and bulk sites; this may be due to the physical constraints associated with matrix structure-associated physical constraints, which sometimes dominate the volume-binding energies.

  5. 41 CFR 101-25.301 - General.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... which shall be applied by all executive agencies. Additional criteria above these minimum standards shall be established by each executive agency, limiting its property to the minimum requirements necessary for the efficient functioning of the particular office concerned. This subpart does not apply to...

  6. A Fuel-Efficient Conflict Resolution Maneuver for Separation Assurance

    NASA Technical Reports Server (NTRS)

    Bowe, Aisha Ruth; Santiago, Confesor

    2012-01-01

    Automated separation assurance algorithms are envisioned to play an integral role in accommodating the forecasted increase in demand of the National Airspace System. Developing a robust, reliable, air traffic management system involves safely increasing efficiency and throughput while considering the potential impact on users. This experiment seeks to evaluate the benefit of augmenting a conflict detection and resolution algorithm to consider a fuel efficient, Zero-Delay Direct-To maneuver, when resolving a given conflict based on either minimum fuel burn or minimum delay. A total of twelve conditions were tested in a fast-time simulation conducted in three airspace regions with mixed aircraft types and light weather. Results show that inclusion of this maneuver has no appreciable effect on the ability of the algorithm to safely detect and resolve conflicts. The results further suggest that enabling the Zero-Delay Direct-To maneuver significantly increases the cumulative fuel burn savings when choosing resolution based on minimum fuel burn while marginally increasing the average delay per resolution.

  7. Science 101: Why Don't Spiders Stick to Their Own Webs?

    ERIC Educational Resources Information Center

    Robertson, Bill

    2011-01-01

    This article explains why spiders don't stick to their webs. Spiders don't get stuck in their own webs (and they aren't immune to their own glue) because they use a combination of sticky and nonsticky threads (different glands for producing those), and the glue is in droplets that the spider can avoid but the prey can't. The spider's nervous…

  8. Studying Hooke's Law by Using a Pogo Stick

    ERIC Educational Resources Information Center

    Silva, Nicolas

    2011-01-01

    Perhaps the pogo stick was little Robert Hooke's favorite childhood toy, consisting of a stiff spring inserted in a tube fixed at the upper end and connected to a moveable rod at the other. Hand grips and a foot rest are connected to the tube. The idea is to jump on it taking advantage of the force provided by the spring when it is compressed.…

  9. Effect of weathering on accuracy of fuel-moisture-indicator sticks in the Pacific Northwest.

    Treesearch

    William G. Morris

    1959-01-01

    How much does weathering affect accuracy of fuel-moisture indicator stick readings in different sections of Oregon and Washington? If unpainted lumber is exposed to weather for a few years, its color changes and the grain shows as much erosion as if it were sandblasted. According to the Forest Products Laboratory, chemical as well as physical changes produce these...

  10. Improved analysis and visualization of friction loop data: unraveling the energy dissipation of meso-scale stick-slip motion

    NASA Astrophysics Data System (ADS)

    Kokorian, Jaap; Merlijn van Spengen, W.

    2017-11-01

    In this paper we demonstrate a new method for analyzing and visualizing friction force measurements of meso-scale stick-slip motion, and introduce a method for extracting two separate dissipative energy components. Using a microelectromechanical system tribometer, we execute 2 million reciprocating sliding cycles, during which we measure the static friction force with a resolution of \

  11. Method for preventing micromechanical structures from adhering to another object

    DOEpatents

    Smith, J.H.; Ricco, A.J.

    1998-06-16

    A method for preventing micromechanical structures from adhering to another object includes the step of immersing a micromechanical structure and its associated substrate in a chemical species that does not stick to itself. The method can be employed during the manufacture of micromechanical structures to prevent micromechanical parts from sticking or adhering to one another and their associated substrate surface. 3 figs.

  12. From Desktop Toy to Educational Aid: Neo Magnets as an Alternative to Ball-and-Stick Models in Representing Carbon Fullerenes

    ERIC Educational Resources Information Center

    Kao, Jacqueline Y.; Yang, Min-Han; Lee, Chi-Young

    2015-01-01

    Neo magnets are neodymium magnet beads that have been marketed as a desktop toy. We proposed using neo magnets as an alternative building block to traditional ball-and-stick models to construct carbon allotropes, such as fullerene and various nanocone structures. Due to the lack of predetermined physical connections, the versatility of carbon…

  13. Epidemiology of Injuries in Women Playing Competitive Team Bat-or-Stick Sports: A Systematic Review and a Meta-Analysis.

    PubMed

    Panagodage Perera, Nirmala Kanthi; Joseph, Corey; Kemp, Joanne Lyn; Finch, Caroline Frances

    2018-03-01

    Team bat-or-stick sports, including cricket, softball and hockey, are popular among women. However, little is known about the injury profile in this population. The aim was to describe the incidence, nature and anatomical location of injuries in bat-or-stick sports played by women in a competitive league. This review was prospectively registered (PROSPERO CRD42015026715). CINAHL, MEDLINE, PsycINFO, PubMed, SPORTDiscus were systematically searched from January 2000 to September 2016, inclusive. Peer-reviewed original research articles reporting the incidence, nature and anatomical location of injuries sustained by women aged 18 + years in competitive bat-or-stick sports were included. Two meta-analyses based on injury incidence proportions (injury IP) and injury rates per 1000 person-days of athletic exposure (AE) were performed. A total of 37 studies satisfied the inclusion criteria, and five had low risk of bias. The weighted injury IP was 0.42 [95% confidence interval (CI) 0.39-0.45]. The weighted injury rate was 6.12 (95% CI 6.05-6.18) overall, and greater in games [15.79 (95% CI 15.65-15.93)] than in practice [3.07 (95% CI 2.99-3.15)]. The ankle was the most commonly injured anatomical location, followed by the hand (including wrist and fingers), knee and head. Soft tissue and ligament injuries were most common types of injuries. Injury prevention in women's sports is a novel and emerging field of research interest. This review highlights that injury incidence is high among female bat-or-stick players, but little information is known about direct causal mechanisms. This review clearly establishes the need for enhancements to injury data collection. Without this information, it will not be possible to develop evidence-based injury prevention interventions.

  14. [Controlled observation of non-blister acupoint sticking and electroacupuncture for bronchial asthma].

    PubMed

    Tian, Hai-Yan; Hu, Jia; Wang, Lin

    2013-06-01

    To compare the differences of clinical efficacy for bronchial asthma between acupoint sticking combined with ginger-separated moxibustion and electroacupuncture combined with ginger-separated moxibustion. With a randomized and controlled method, one hundred cases were divided into an acupoint sticking + ginger-separated moxibustion group (group A) and an electroacupuncture + ginger-separated moxibustion group (group E), 50 cases in each one. The Dazhui (GV 14), Feishu (BL 13), Tiantu (CV 22) and so on were selected in both groups. The treatment was given on the 1st day of each dog-day period and each nine-day period after the winter solstice separately. The ginger-separated moxibustion was applied in the group A, which was followed by plaster sticking that was made with Chinese herbs (including white mustard seed, rhizoma corydalis, euphorbia kansui, asarum), glycerin and warm ginger juice. The regular acupuncture, electroacupuncture and ginger-separated moxibustion were applied in the group E. The scores of recovery cough, control asthma, respiratory frequency, stuffiness chest, wheezing and markedly and cured effective rate were compared in two groups before and after the treatment. The markedly and cured effective rate was 72.0% (36/50) in the group A, which was superior to 46.0% (23/50) in the group E (P < 0.05). All the symptom scores in two groups were obviously improved after the treatment, in which group A was superior to group E (all P < 0.05). The acupoint sticking and ginger-separated moxibustion could obviously improve clinical symptoms in patients with bronchial asthma, and reduce skin irritation of medicine to avoid the blister and relive patients' suffer, which has superior effect to electroacupuncture combined with ginger-separated moxibustion.

  15. The prevalence of olfactory dysfunction in chronic rhinosinusitis.

    PubMed

    Kohli, Preeti; Naik, Akash N; Harruff, E Emily; Nguyen, Shaun A; Schlosser, Rodney J; Soler, Zachary M

    2017-02-01

    Many studies have reported that olfactory dysfunction frequently occurs in chronic rhinosinusitis (CRS) populations; however, the prevalence and degree of olfactory loss has not been systematically studied. The aims of this study were to use combined data to report the prevalence of olfactory dysfunction and to calculate weighted averages of olfactory test scores in CRS patients. A search was conducted in PubMed and Scopus, following the methods of Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Studies reporting the prevalence of olfactory dysfunction using objective measures or olfactory test scores using validated scales were included. A total of 47 articles were included in a systematic review and 35 in the pooled data analysis. The prevalence of olfactory dysfunction in chronic rhinosinusitis was found to be 30.0% using the Brief Smell Identification Test, 67.0% using the 40-item Smell Identification Test, and 78.2% using the total Sniffin' Sticks score. Weighted averages ± standard deviation of olfactory test scores were 25.96 ± 7.11 using the 40-item Smell Identification Test, 8.60 ± 2.81 using the Brief Smell Identification Test, 21.96 ± 8.88 using total Sniffin' Sticks score, 5.65 ± 1.51 using Sniffin' Sticks-Threshold, 9.21 ± 4.63 using Sniffin' Sticks-Discrimination, 9.47 ± 3.92 using Sniffin' Sticks-Identification, and 8.90 ± 5.14 using the Questionnaire for Olfactory Disorders-Negative Statements. In CRS populations, a significant percentage of patients experience olfactory dysfunction, and mean olfactory scores are within the dysosmic range. Laryngoscope, 2016 127:309-320, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  16. Analog-Computer Investigation of Effects of Friction and Preload on the Dynamic Longitudinal Characteristics of a Pilot-Airplane Combination

    NASA Technical Reports Server (NTRS)

    Crane, Harold L.

    1961-01-01

    With an electric analog computer, an investigation has been made of the effects of control frictions and preloads on the transient longitudinal response of a fighter airplane during abrupt small attitude corrections. The simulation included the airplane dynamics, powered control system, feel system, and a simple linearized pseudopilot. Control frictions at the stick pivot and at the servo valve as well as preloads of the stick and valve were considered individually and in combinations. It is believed that the results which are presented in the form of time histories and vector diagrams present a more detailed illustration of the effects of stray forces and compensating forces in the longitudinal control system than has previously been available. Consistent with the results of previous studies, the present results show that any of these four friction and preload forces caused some deterioration of the response. However, even a small amount of valve friction caused an oscillatory pitching response during which the phasing of the valve friction was such that it caused energy to be fed into the pitching oscillation of the air-plane. Of the other friction and preload forces which were considered, it was found that stick preload was close to 180 deg. out of phase with valve friction and thus could compensate in large measure for valve friction as long as the cycling of the stick encompassed the trim point. Either stick friction or valve preload provided a smaller stabilizing effect primarily through a reduction in the amplitude of the resultant force vector acting on the control system. Some data were obtained on the effects of friction when the damping or inertia of the control system or the pilot lag was varied.

  17. Analog-computer investigation of effects of friction and preload on the dynamic longitudinal characteristics of a pilot-airplane combination

    NASA Technical Reports Server (NTRS)

    Crane, Harold L

    1957-01-01

    With an electric analog computer, an investigation has been made of the effects of control frictions and preloads on the transient longitudinal response of a fighter airplane during abrupt small attitude corrections. The simulation included the airplane dynamics, powered control system, feel system, and a simple linearized pseudopilot. Control frictions at the stick pivot and at the servo valve as well as preloads of the stick and valve were considered individually and in combinations. It is believed that the results which are presented in the form of time histories and vector diagrams present a more detailed illustration of the effects of stray forces and compensating forces in the longitudinal control system than has previously been available. Consistent with the results of previous studies, the present results show that any of thesefour friction and preload forces caused some deterioration of the response. However, even a small amount of valve friction caused an oscillatory pitching response during which the phasing of the valve friction was such that it caused energy to be fed into the pitching oscillation of the airplane. Of the other friction and preload forces which were considered, it was found that stick preload was close to 180 degrees out of phase with valve friction and thus could compensate in large measure for valve friction as long as the cycling of the stick encompassed the trim point. Either stick friction or valve preload provided a smaller stabilizing effect primarily through a reduction in the amplitude of the resultant force vector acting on the control system. Some data were obtained on the effects of friction when the damping or inertia of the control system or the pilot lag was varied.

  18. Wooden Calendars from Central Rhodopes

    NASA Astrophysics Data System (ADS)

    Koleva, V.

    2008-10-01

    Four wooden calendars from the village of Polkovnik Serafimovo, Smolyan region, in the Central Rhodopes are presented here, and three of them - for the first time. The shape and size, the kind of the signs and structure of the calendar record bear the characteristic features of the rest of the Bulgarian wooden calendars. The short notches on the edges represent the days of the year in the Julian (solar) calendar. The special signs on the sides mark the fixed festivals of the Orthodox Church calendar and are also influenced by the local tradition. The type of the signs confirms that the wooden sticks belong to the group of calendars from the Central Rhodopes. According to the beginning date of the calendar record on the sticks, two of the calendars are of the April (May) or October (November) type which corresponds to the very popular economic division of the year in the folk calendar into two periods -- warm and cold. The other two sticks, which are very similar to each other, make an exception in this respect among the rest of the Bulgarian wooden calendars. The months are divided into four groups (seasons) on each of the four edges of the stick (only one calendar from Burgas region has the same structure). The most interesting thing about the two sticks is that this is the only case among all known Bulgarian calendars that the beginning of the calendar record coincides with the beginning of the civil year on 1st January (January type) like some wooden calendars from Western Europe. Nowadays it is getting harder and harder to find wooden calendars in Bulgaria and in the neighbouring Balkan countries. The thorough knowledge about them could be helpful in various scientific fields, e.g. history of religion, ethnology, history of astronomy and mathematics, as well as semiotics.

  19. The advertised price of cigarette packs in retail outlets across Australia before and after the implementation of plain packaging: a repeated measures observational study

    PubMed Central

    Scollo, Michelle; Bayly, Megan; Wakefield, Melanie

    2015-01-01

    Objective This study monitored the advertised price of the most prominently promoted and the cheapest single packs of cigarettes in Australian retail outlets before and after the implementation of plain packaging. Methods A panel of 421 outlets in four large Australian cities was visited monthly from May 2012 to August 2013 and the brand, pack size and price of the most-prominently listed and lowest-priced single cigarette pack were recorded from each store's tobacco price board. Changes in the inflation-adjusted stick price were examined using linear mixed models, controlling for fixed effects of city, store type, area socioeconomic status and random effects of time. The adjusted stick price was also examined over time by tobacco manufacturer and pack size. Results The inflation-adjusted stick price of the most-prominently advertised single packs was significantly higher than in May–July 2012 from August–October 2012 for mainstream and premium brands and from February–April 2013 for value brands. Adjusted average stick prices of lowest-priced packs in August 2013 were $0.02 (95% CI $0.02 to $0.03, p<0.001) higher than in May–July 2012 ($Aug13). A large real increase in stick price was seen in February–April 2013 across all major manufacturers, market segments and pack size categories. Discussion The price of cigarettes most prominently promoted on price boards did not decrease in the months following implementation of Australia's plain packaging legislation. Retail prices continued to increase above the level resulting from automatic indexation of excise/customs duty even at the lowest-priced end of the Australian market. PMID:28407616

  20. Retention strength of impression materials to a tray material using different adhesive methods: an in vitro study.

    PubMed

    Marafie, Yousef; Looney, Stephen; Nelson, Steven; Chan, Daniel; Browning, William; Rueggeberg, Frederick

    2008-12-01

    A new self-stick adhesive system has been purported to eliminate the need to use chemical adhesives with plastic impression trays; however, no testing has confirmed the claim. The purpose of this study was to compare the in vitro retentive strength of impression materials to plastic substrates having conventional adhesive (CA) or the self-stick adhesive system, with and without mechanical retention. Three types of impression materials (irreversible hydrocolloid (IH), vinyl polysiloxane (VPS), and polyether (PE)) were applied to polystyrene disc-shaped surfaces (33.68 cm(2)) that were held on the arms of a universal testing machine. The appropriate CA or the self-stick adhesive system (Self-Stick Dots) (SSD) was applied to the plates, which had either no mechanical retention, or equally spaced mechanical perforations (n=4). An in vivo pilot test determined the appropriate rate of plate separation. Plates with impression material were lowered to provide 4 mm of space, the material set, and plates were separated using the appropriate speed. Force at first separation was divided by plate area (peak stress). Five replications per test condition were made, and results were analyzed using ANOVA and Bonferroni-adjusted t tests (alpha=.05). Within each impression material/test combination, stress using SSD was significantly lower than CA (P<.05). Mechanical retention did not always provide significantly greater strength. The combination of mechanical retention and CA yielded the highest strength within each material type, except for PE, for which nonmechanical and CA strength did not differ from that of mechanical and CA. Use of the self-stick adhesive system provided significantly lower retentive strength to plastic tray material than chemical adhesives for irreversible hydrocolloid, vinyl polysiloxane, and polyether.

  1. Initial versus final fracture of metal-free crowns, analyzed via acoustic emission.

    PubMed

    Ereifej, Nadia; Silikas, Nick; Watts, David C

    2008-09-01

    To discriminate between initial and final fracture failure loads of four metal-free crown systems by the conjoint detection of acoustic emission signals during compressive loading. Teeth were prepared and used for crown construction with four crown systems; Vita Mark II (VM II) (Vita Zahnfabrik), IPS e.max Ceram/CAD (CAD) (Ivoclar-Vivadent), IPS e.max Ceram/ZirCAD (ZirCAD) (Ivoclar-Vivadent) and BelleGlass/EverStick (BGES) (Kerr/Stick Tech Ltd.). All samples were loaded in compression via a Co/Cr maxillary first molar tooth at 0.2mm/min and released acoustic signals were collected and analyzed. A minimum number of 15 crowns per group were loaded to final failure and values of loading at initial and final fracture were compared. Additional four samples per group were loaded till fracture initiation and were fractographically examined under the optical microscope. A lower threshold of 50dB was selected to exclude spurious background signals. Initial fracture forces were significantly lower than those of final fracture (p<0.05) in all groups and initial failure AE amplitudes were lower than those of final fracture. Mean initial fracture force of ZirCAD samples (1029.1N) was higher than those of VMII (744.4N), CAD (808.8 N) and BGES (979.7 N). Final fracture of ZirCAD also occurred at significantly higher force values (2091.7 N) than the rest of the groups; VMII (1120.9 N), CAD (1468.9 N) and BGES (1576.6 N). Significantly higher values of initial failure AE amplitude were found in VMII than CAD and BGES while those of final fracture were similar. All crowns observed under the microscope at initial fracture had signs of failure. Whereas the metal-free crowns examined showed significant variations in final failure loads, acoustic emission data showed that they all manifested initial failures at significantly lower load values.

  2. Identification, rearing, and distribution of stick insects of Madeira Island: An example of raising biodiversity awareness

    PubMed Central

    Aguiar, António M. F.; Pombo, Dora Aguin; Gonçalves, Ysabel M.

    2014-01-01

    Abstract Two species of stick insects are currently known to be present in the Macaronesian archipelagos: Clonopsis gallica (Charpentier) (Phasmatodea: Bacillidae) on the Canary Islands and in the Azores and Carausius morosus (Sinéty) (Phasmatidae) in the Azores. Here, we provide the first reliable records of the presence and distribution of C. gallica and C. morosus on Madeira Island. Egg and adult stages are briefly described along with some notes on the life history of these species in captivity. Data on islandwide distribution are based on specimens donated by the public in response to an article published in a daily newspaper. This method of data collection raised great popular interest in stick insects. The role of newspapers as a means of communicating awareness in biodiversity issues is discussed. PMID:25373196

  3. Linking the Pilot Structural Model and Pilot Workload

    NASA Technical Reports Server (NTRS)

    Bachelder, Edward; Hess, Ronald; Aponso, Bimal; Godfroy-Cooper, Martine

    2018-01-01

    Behavioral models are developed that closely reproduced pulsive control response of two pilots using markedly different control techniques while conducting a tracking task. An intriguing find was that the pilots appeared to: 1) produce a continuous, internally-generated stick signal that they integrated in time; 2) integrate the actual stick position; and 3) compare the two integrations to either issue or cease a pulse command. This suggests that the pilots utilized kinesthetic feedback in order to sense and integrate stick position, supporting the hypothesis that pilots can access and employ the proprioceptive inner feedback loop proposed by Hess's pilot Structural Model. A Pilot Cost Index was developed, whose elements include estimated workload, performance, and the degree to which the pilot employs kinesthetic feedback. Preliminary results suggest that a pilot's operating point (parameter values) may be based on control style and index minimization.

  4. Orientation with a Viking sun-compass, a shadow-stick, and two calcite sunstones under various weather conditions.

    PubMed

    Bernáth, Balázs; Blahó, Miklós; Egri, Adám; Barta, András; Kriska, György; Horváth, Gábor

    2013-09-01

    It is widely accepted that Vikings used sun-compasses to derive true directions from the cast shadow of a gnomon. It has been hypothesized that when a cast shadow was not formed, Viking navigators relied on crude skylight polarimetry with the aid of dichroic or birefringent crystals, called "sunstones." We demonstrate here that a simple tool, that we call "shadow-stick," could have allowed orientation by a sun-compass with satisfying accuracy when shadows were not formed, but the sun position could have reliably been estimated. In field tests, we performed orientation trials with a set composed of a sun-compass, two calcite sunstones, and a shadow-stick. We show here that such a set could have been an effective orientation tool for Vikings only when clear, blue patches of the sky were visible.

  5. 1952 midsummer fuel moistures in Oregon and Washington national forests compared with other years.

    Treesearch

    Owen P. Cramer

    1953-01-01

    The inflammability of Oregon and Washington national forests during the middle of the 1952 fire season was slightly lass than the 12-year record high set in 1951 (table 1). The rating is based on the 25 lowest daily observations of fuel-moisture indicator sticks in the July 16 to August 21 period. Stick readings from 64 key fire-danger stations near the exterior...

  6. A change management approach to improving safety and preventing needle stick injuries.

    PubMed

    Aziz, Ann-Marie

    2017-09-01

    Key drivers for preventing healthcare-associated infection (HCAI) include evidence-based practices and procedures that prevent infection. Among the current guidance for preventing HCAIs is evidence and mandatory requirements for reducing needle stick injuries (NSIs). This article highlights how John Kotter's model for change could help healthcare workers plan for successful and sustained deployment of needle safety devices (NSDs) and ultimately reduce the risk of a NSI.

  7. "We Tend to Stick Together and Mostly We Stick to Our Own Kind": British Indian Women and Support Networks at University

    ERIC Educational Resources Information Center

    Bhopal, Kalwant

    2011-01-01

    This paper will examine the support networks that are available to British Indian women studying at a "new" (post-1992) university in the South-East of England, UK. It will examine the support that women draw upon whilst at university and discuss the ways in which these support networks enable women to develop strategies for success.…

  8. Qualitative Simulator Study of Longitudinal Stick Forces and Displacements Desirable During Tracking

    NASA Technical Reports Server (NTRS)

    Faber, Stanley

    1958-01-01

    In this study in which an airplane simulator with one degree of freedom (pitch) was used, results were determined for three conditions of airplane dynamics. For an undamped natural frequency of 1/2 cps with a damping ratio of 0.18 and for an undamped natural frequency of 1 cps with a damping ratio of 0.11, moderate longitudinal stick forces and displacements were desired.

  9. Effects of wind velocity and slope on fire behavior

    Treesearch

    D.R. Weise; G.S. Biging

    1994-01-01

    Effects of wind velocity and slope on fire spread rate and flame length were examined. Fuel beds of vertical sticks (13.97 cm x 0.455 cm x 0.1 10 cm) and coarse excelsior were burned in an open-topped tilting wind tunnel. Mean fuel moisture content of sticks and excelsior was 11% and 12%, respectively. Mean surface area to volume ratio was 23 cm-! Five slopes (negative...

  10. Moiré superlattice-level stick-slip instability originated from geometrically corrugated graphene on a strongly interacting substrate

    NASA Astrophysics Data System (ADS)

    Shi, Ruoyu; Gao, Lei; Lu, Hongliang; Li, Qunyang; Ma, Tian-Bao; Guo, Hui; Du, Shixuan; Feng, Xi-Qiao; Zhang, Shuai; Liu, Yanmin; Cheng, Peng; Hu, Yuan-Zhong; Gao, Hong-Jun; Luo, Jianbin

    2017-06-01

    Two dimensional (2D) materials often exhibit novel properties due to various coupling effects with their supporting substrates. Here, using friction force microscopy (FFM), we report an unusual moiré superlattice-level stick-slip instability on monolayer graphene epitaxially grown on Ru(0 0 0 1) substrate. Instead of smooth friction modulation, a significant long-range stick-slip sawtooth modulation emerges with a period coinciding with the moiré superlattice structure, which is robust against high external loads and leads to an additional channel of energy dissipation. In contrast, the long-range stick-slip instability reduces to smooth friction modulation on graphene/Ir(1 1 1) substrate. The moiré superlattice-level slip instability could be attributed to the large sliding energy barrier, which arises from the morphological corrugation of graphene on Ru(0 0 0 1) surface as indicated by density functional theory (DFT) calculations. The locally steep humps acting as obstacles opposing the tip sliding, originates from the strong interfacial electronic interaction between graphene and Ru(0 0 0 1). This study opens an avenue for modulating friction by tuning the interfacial atomic interaction between 2D materials and their substrates.

  11. Sticking and recombination of the SiH 3 radical on hydrogenated amorphous silicon: The catalytic effect of diborane

    NASA Astrophysics Data System (ADS)

    Perrin, Jérôme; Takeda, Yoshihiko; Hirano, Naoto; Takeuchi, Yoshiaki; Matsuda, Akihisa

    1989-03-01

    The deposition rate of hydrogenated amorphous silicon films in SiH 4 glow-discharge is drastically enhanced upon addition of B 2H 6 when the gas-phase concentration exceeds 10 -4. This cannot be attributed to gas-phase reactions and must be interpreted as an increase of the sticking probability of the dominant SiH 3 radical. However, the total surface loss probability ( β) of SiH 3 which includes both sticking ( s) and recombination ( γ) increases only above 10 -2 B 2H 6 concentration, which reveals that between 10 -4 and 10 -2 the ratio {s}/{β} increases. A precursor-state model is proposed in which SiH 3 first physisorbs on the H-covered surface and migrates until it recombines, or chemisorbs on a free dangling bond site. At a typical deposition temperature of 200° C, the only mechanism of creation of dangling bonds in the absence of B 2H 6 is precisely the recombination of SiH 3 as SiH 4 by H abstraction, which limits the sticking probability to a fraction of β. This restriction is overcome with the help of hydroboron radicals, presumably BH 3, which catalyze H 2 desorption.

  12. Inertial and stick-slip regimes of unstable adhesive tape peeling.

    PubMed

    Dalbe, Marie-Julie; Villey, Richard; Ciccotti, Matteo; Santucci, Stéphane; Cortet, Pierre-Philippe; Vanel, Loïc

    2016-05-18

    We present an experimental characterization of the detachment front unstable dynamics observed during the peeling of pressure sensitive adhesives. We use an experimental set-up specifically designed to control the peeling angle θ and the peeled tape length L, while peeling an adhesive tape from a flat substrate at a constant driving velocity V. High-speed imaging allows us to report the evolution of the period and amplitude of the front oscillations, as well as the relative durations of their fast and slow phases, as a function of the control parameters V, L and θ. Our study shows that, as the driving velocity or the peeling angle increases, the oscillations of the peeling front progressively evolve from genuine "stick-slip" oscillations, made of alternating long stick phases and very brief slip phases, to sinusoidal oscillations of amplitude twice the peeling velocity. We propose a model which, taking into account the peeling angle-dependent kinetic energy cost to accelerate and decelerate the peeled tape, explains the transition from the "stick-slip" to the "inertial" regime of the dynamical instability. Using independent direct measurements of the effective fracture energy of the adhesive-substrate joint, we show that our model quantitatively accounts for the two regimes of the unstable dynamics.

  13. Earthquake source properties from instrumented laboratory stick-slip

    USGS Publications Warehouse

    Kilgore, Brian D.; McGarr, Arthur F.; Beeler, Nicholas M.; Lockner, David A.; Thomas, Marion Y.; Mitchell, Thomas M.; Bhat, Harsha S.

    2017-01-01

    Stick-slip experiments were performed to determine the influence of the testing apparatus on source properties, develop methods to relate stick-slip to natural earthquakes and examine the hypothesis of McGarr [2012] that the product of stiffness, k, and slip duration, Δt, is scale-independent and the same order as for earthquakes. The experiments use the double-direct shear geometry, Sierra White granite at 2 MPa normal stress and a remote slip rate of 0.2 µm/sec. To determine apparatus effects, disc springs were added to the loading column to vary k. Duration, slip, slip rate, and stress drop decrease with increasing k, consistent with a spring-block slider model. However, neither for the data nor model is kΔt constant; this results from varying stiffness at fixed scale.In contrast, additional analysis of laboratory stick-slip studies from a range of standard testing apparatuses is consistent with McGarr's hypothesis. kΔt is scale-independent, similar to that of earthquakes, equivalent to the ratio of static stress drop to average slip velocity, and similar to the ratio of shear modulus to wavespeed of rock. These properties result from conducting experiments over a range of sample sizes, using rock samples with the same elastic properties as the Earth, and scale-independent design practices.

  14. Hydrogen collisions with transition metal surfaces: Universal electronically nonadiabatic adsorption

    NASA Astrophysics Data System (ADS)

    Dorenkamp, Yvonne; Jiang, Hongyan; Köckert, Hansjochen; Hertl, Nils; Kammler, Marvin; Janke, Svenja M.; Kandratsenka, Alexander; Wodtke, Alec M.; Bünermann, Oliver

    2018-01-01

    Inelastic scattering of H and D atoms from the (111) surfaces of six fcc transition metals (Au, Pt, Ag, Pd, Cu, and Ni) was investigated, and in each case, excitation of electron-hole pairs dominates the inelasticity. The results are very similar for all six metals. Differences in the average kinetic energy losses between metals can mainly be attributed to different efficiencies in the coupling to phonons due to the different masses of the metal atoms. The experimental observations can be reproduced by molecular dynamics simulations based on full-dimensional potential energy surfaces and including electronic excitations by using electronic friction in the local density friction approximation. The determining factors for the energy loss are the electron density at the surface, which is similar for all six metals, and the mass ratio between the impinging atoms and the surface atoms. Details of the electronic structure of the metal do not play a significant role. The experimentally validated simulations are used to explore sticking over a wide range of incidence conditions. We find that the sticking probability increases for H and D collisions near normal incidence—consistent with a previously reported penetration-resurfacing mechanism. The sticking probability for H or D on any of these metals may be represented as a simple function of the incidence energy, Ein, metal atom mass, M, and incidence angle, 𝜗i n. S =(S0+a ṡEi n+b ṡM ) *(1 -h (𝜗i n-c ) (1 -cos(𝜗 i n-c ) d ṡh (Ei n-e ) (Ei n-e ) ) ) , where h is the Heaviside step function and for H, S0 = 1.081, a = -0.125 eV-1, b =-8.40 ṡ1 0-4 u-1, c = 28.88°, d = 1.166 eV-1, and e = 0.442 eV; whereas for D, S0 = 1.120, a = -0.124 eV-1, b =-1.20 ṡ1 0-3 u-1, c = 28.62°, d = 1.196 eV-1, and e = 0.474 eV.

  15. CCOMP: An efficient algorithm for complex roots computation of determinantal equations

    NASA Astrophysics Data System (ADS)

    Zouros, Grigorios P.

    2018-01-01

    In this paper a free Python algorithm, entitled CCOMP (Complex roots COMPutation), is developed for the efficient computation of complex roots of determinantal equations inside a prescribed complex domain. The key to the method presented is the efficient determination of the candidate points inside the domain which, in their close neighborhood, a complex root may lie. Once these points are detected, the algorithm proceeds to a two-dimensional minimization problem with respect to the minimum modulus eigenvalue of the system matrix. In the core of CCOMP exist three sub-algorithms whose tasks are the efficient estimation of the minimum modulus eigenvalues of the system matrix inside the prescribed domain, the efficient computation of candidate points which guarantee the existence of minima, and finally, the computation of minima via bound constrained minimization algorithms. Theoretical results and heuristics support the development and the performance of the algorithm, which is discussed in detail. CCOMP supports general complex matrices, and its efficiency, applicability and validity is demonstrated to a variety of microwave applications.

  16. Disilane as a growth rate catalyst of plasma deposited microcrystalline silicon thin films

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dimitrakellis, P.; Amanatides, E., E-mail: lef@plasmatech.gr; Mataras, D.

    2016-07-15

    The effect of small disilane addition on the gas phase properties of silane-hydrogen plasmas and the microcrystalline silicon thin films growth is presented. The investigation was conducted in the high pressure regime and for constant power dissipation in the discharge with the support of plasma diagnostics, thin film studies and calculations of discharge microscopic parameters and gas dissociation rates. The experimental data and the calculations show a strong effect of disilane on the electrical properties of the discharge in the pressure window from 2 to 3 Torr that is followed by significant raise of the electron number density and themore » drop of the sheaths electric field intensity. Deposition rate measurements show an important four to six times increase even for disilane mole fractions as low as 0.3 %. The deposition rate enhancement was followed by a drop of the material crystalline volume fraction but films with crystallinity above 40 % were deposited with different combinations of total gas pressure, disilane and silane molar ratios. The enhancement was partly explained by the increase of the electron impact dissociation rate of silane which rises by 40% even for 0.1% disilane mole fraction. The calculations of the gas usage, the dissociation and the deposition efficiencies show that the beneficial effect on the growth rate is not just the result of the increase of Si-containing molecules density but significant changes on the species participating to the deposition and the mechanism of the film growth are caused by the disilane addition. The enhanced participation of the highly sticking to the surface radical such as disilylene, which is the main product of disilane dissociation, was considered as the most probable reason for the significant raise of the deposition efficiency. The catalytic effect of such type of radical on the surface reactivity of species with lower sticking probability is further discussed, while it is also used to explain the restricted and sensitive process window where the disilane effect appears.« less

  17. Disilane as a growth rate catalyst of plasma deposited microcrystalline silicon thin films

    NASA Astrophysics Data System (ADS)

    Dimitrakellis, P.; Kalampounias, A. G.; Spiliopoulos, N.; Amanatides, E.; Mataras, D.; Lahootun, V.; Coeuret, F.; Madec, A.

    2016-07-01

    The effect of small disilane addition on the gas phase properties of silane-hydrogen plasmas and the microcrystalline silicon thin films growth is presented. The investigation was conducted in the high pressure regime and for constant power dissipation in the discharge with the support of plasma diagnostics, thin film studies and calculations of discharge microscopic parameters and gas dissociation rates. The experimental data and the calculations show a strong effect of disilane on the electrical properties of the discharge in the pressure window from 2 to 3 Torr that is followed by significant raise of the electron number density and the drop of the sheaths electric field intensity. Deposition rate measurements show an important four to six times increase even for disilane mole fractions as low as 0.3 %. The deposition rate enhancement was followed by a drop of the material crystalline volume fraction but films with crystallinity above 40 % were deposited with different combinations of total gas pressure, disilane and silane molar ratios. The enhancement was partly explained by the increase of the electron impact dissociation rate of silane which rises by 40% even for 0.1% disilane mole fraction. The calculations of the gas usage, the dissociation and the deposition efficiencies show that the beneficial effect on the growth rate is not just the result of the increase of Si-containing molecules density but significant changes on the species participating to the deposition and the mechanism of the film growth are caused by the disilane addition. The enhanced participation of the highly sticking to the surface radical such as disilylene, which is the main product of disilane dissociation, was considered as the most probable reason for the significant raise of the deposition efficiency. The catalytic effect of such type of radical on the surface reactivity of species with lower sticking probability is further discussed, while it is also used to explain the restricted and sensitive process window where the disilane effect appears.

  18. Dust, endotoxin, fungi, and bacteria exposure as determined by work task, season, and type of plant in a flower greenhouse.

    PubMed

    Thilsing, Trine; Madsen, Anne Mette; Basinas, Ioannis; Schlünssen, Vivi; Tendal, Kira; Bælum, Jesper

    2015-03-01

    Greenhouse workers are exposed to dust, endotoxin, fungi, and bacteria potentially causing airway inflammation as well as systemic symptoms. Knowledge about determinants of exposure is a prerequisite for efficient prevention through knowledge-based reduction in exposure. The objective of this study was to assess the occupational exposure in a flower greenhouse and to investigate the impact of work tasks on the intensity and variability in exposure. Seventy-six personal full-shift exposure measurements were performed on 38 employees in a Danish flower greenhouse producing Campanula, Lavandula, Rhipsalideae, and Helleborus. The samples were gravimetrically analysed for inhalable dust. Endotoxin was assessed by the Limulus Amoebocyte Lysate test and culture-based quantification of bacteria and fungi was performed. Information on the performed tasks during sampling was extracted from the greenhouse electronic task logging system. Associations between log-transformed exposure outcomes, season, and work tasks were examined in linear mixed-effects regression with worker identity as random effect. Measured concentrations ranged between 0.04 and 2.41mg m(-3) for inhalable dust and between 0.84 and 1097 EU m(-3) for endotoxin exposure, with the highest mean levels measured during Lavandula and Campanula handling, respectively. Personal exposure to fungi ranged between 1.8×10(2) and 3.4×10(6) colony-forming units (CFU) m(-3) and to bacteria between 1.6×10(1) and 4.2×10(5) CFU m(-3). Exposure to dust, endotoxin, fungi, and bacteria differed between seasons. Packing Lavandula, sticking, potting, and grading Rhipsalideae, and all examined tasks related to Campanula production except sticking increased dust exposure. Endotoxin exposure was increased during sticking Campanula and pinching or packing Rhipsalideae, and fungi exposure was elevated by subtasks performed in the research and development area for Campanula, and by potting, packing/dumping Campanula. Sticking and working with subtasks in the research and development area for Campanula increased bacteria exposure. This study revealed moderate dust exposure levels compared to the levels observed in other greenhouse productions and other occupations with organic dust exposure such as farming. However, high exposures to bacteria and fungi were detected during selected tasks and the proposed health-based endotoxin exposure limit of 90 EU m(-3) was exceeded in 30% of the samples, which may have health implications for the employees. Exposure levels were found to vary depending on the tasks performed, and thereby results can be used to direct task-based initiatives to reduce workplace exposures. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  19. Nonparametric Bayesian models through probit stick-breaking processes

    PubMed Central

    Rodríguez, Abel; Dunson, David B.

    2013-01-01

    We describe a novel class of Bayesian nonparametric priors based on stick-breaking constructions where the weights of the process are constructed as probit transformations of normal random variables. We show that these priors are extremely flexible, allowing us to generate a great variety of models while preserving computational simplicity. Particular emphasis is placed on the construction of rich temporal and spatial processes, which are applied to two problems in finance and ecology. PMID:24358072

  20. Nonparametric Bayesian models through probit stick-breaking processes.

    PubMed

    Rodríguez, Abel; Dunson, David B

    2011-03-01

    We describe a novel class of Bayesian nonparametric priors based on stick-breaking constructions where the weights of the process are constructed as probit transformations of normal random variables. We show that these priors are extremely flexible, allowing us to generate a great variety of models while preserving computational simplicity. Particular emphasis is placed on the construction of rich temporal and spatial processes, which are applied to two problems in finance and ecology.

  1. Alternating Days of Intermittent Hypoxic Exposure (IHE) on Physical and Cognitive Performance

    DTIC Science & Technology

    2011-03-01

    IHE) ( Millet , Roels, Schmitt, Woorons, & Richalet, 2010). Athletes or airmen must be located close to a moderate altitude to perform any of the first...recovery until their heart rate dropped below 120 bpm. At the one-minute recovery stage, the subject received a finger stick for blood lactate collection...recovery, the subject received a finger stick for blood lactate collection. These one-minute post-test lactates were analyzed using the Lactate

  2. Redesign and Rehost of the BIG STICK Nuclear Wargame Simulation

    DTIC Science & Technology

    1988-12-01

    described by Pressman [16]. The 4GT soft- ware development approach consists of four iterative phases: the requirements gathering phase, the design strategy...2. BIG STICK Instructions and Planning Guidance. Air Command and Staff College, Air University, Maxwell AFB AL, 1987. Unpublished Manual. 3. Barry W...Software Engineering Notes, 7:29-32, April 1982. 81 17. Roger S. Pressman . Software Engineering: A Practitioner’s Approach. Mc-Craw-llill Book

  3. Improved capture of stable flies (Diptera: Muscidae) by placement of Knight Stick sticky fly traps protected by electric fence inside animal exhibit yards at the Smithsonian’s National Zoological Park

    USDA-ARS?s Scientific Manuscript database

    The stable fly is a blood-feeding pest of livestock and other animals. Traps have been used to survey stable flies and reduce populations. The Knight Stick trap is highly effective for catching stable flies and may catch more if limits on trap placement were relaxed. When working on stable fly contr...

  4. Field evaluation of New Mountain Sandalwood Mosquito Sticks and New Mountain Sandalwood Botanical Repellent against mosquitoes in North Queensland, Australia.

    PubMed

    Ritchie, Scott A; Williams, Craig R; Montgomery, Brian L

    2006-03-01

    The mosquito repellent efficacy of New Mountain Sandalwood Mosquito Sticks (containing 0.5% w/w essential oils) and New Mountain Sandalwood Botanical Repellent (containing soybean and geranium oils) was assessed. Tests were conducted in the field with 4 volunteers in a wooded area near Cairns, North Queensland, Australia. Predominant biting species were Verrallina funerea and Ve. lineata. A pair of burning Mosquito Sticks immediately upwind of the subject (acting as an area repellent) provided a 73.1% mean reduction in mosquito landing and probing over the 3-h test period. The Botanical Repellent and a DEET-based control were both 100% effective in preventing mosquito probing for 3 h. These data are consistent with other studies of area repellents in that such products provide significant protection from mosquito bites, albeit inferior to the protection provided by topically applied repellents.

  5. Stick-Shape, Rice-Size Features on Martian Rock "Haroldswick"

    NASA Image and Video Library

    2018-02-08

    The dark, stick-shaped features clustered on this Martian rock are about the size of grains of rice. This is a focus-merged view from the Mars Hand Lens Imager (MAHLI) camera on NASA's Curiosity Mars rover. It covers an area about 2 inches (5 centimeters) across. The focus-merged product was generated autonomously by MAHLI combining the in-focus portions of a few separate images taken at different focus settings on Jan. 1, 2018, during the 1,922nd Martian day, or sol, of Curiosity's work on Mars. This rock target, called "Haroldswick," is near the southern, uphill edge of "Vera Rubin Ridge" on lower Mount Sharp. The origin of the stick-shaped features is uncertain. One possibility is that they are erosion-resistant bits of dark material from mineral veins cutting through rocks in this area. https://photojournal.jpl.nasa.gov/catalog/PIA22213

  6. A fundamental study of the sticking of insect residues to aircraft wings

    NASA Technical Reports Server (NTRS)

    Eiss, N. S., Jr.; Wightman, J. P.; Gilliam, D. R.; Siochi, E. J.

    1985-01-01

    The aircraft industry has long been concerned with the increase of drag on airplanes due to fouling of the wings by insects. The present research studied the effects of surface energy and surface roughness on the phenomenon of insect sticking. Aluminum plates of different roughnesses were coated with thin films of polymers with varying surface energies. The coated plates were attached to a custom jig and mounted on top of an automobile for insect collection. Contact angle measurements, X-ray photoelectron spectroscopy and specular reflectance infrared spectroscopy were used to characterize the surface before and after the insect impact experiments. Scanning electron microscopy showed the topography of insect residues on the exposed plates. Moments were calculated in order to find a correlation between the parameters studied and the amount of bugs collected on the plates. An effect of surface energy on the sticking of insect residues was demonstrated.

  7. A synthetic aperture microwave radiometer to measure soil moisture and ocean salinity from space

    NASA Technical Reports Server (NTRS)

    Le Vine, D. M.; Hilliard, L. M.; Swift, C. T.; Ruf, C. S.; Garrett, L. B.

    1991-01-01

    A concept is presented for a microwave radiometer in space to measure soil moisture and ocean salinity as part of an 'Earth Probe' mission. The measurements could be made using an array of stick antennas. The L-band channel (1.4 GHz) would be the primary channel for determining soil moisture, with the S-band (2.65-GHz) and C-band (5.0-GHz) channels providing ancillary information to help correct for the effects of the vegetation canopy and possibly to estimate a moisture profile. A preliminary study indicates that an orbit at 450 km would provide coverage of better than 95 percent of the earth every 3 days. A 10-km resolution cell (at nadir) requires stick antennas about 9.5-m long at L-band. The S-band and C-band sticks would be substantially shorter (5 m and 2.7 m, respectively).

  8. Individual Differences in the Flexibility of Peripersonal Space.

    PubMed

    Hunley, Samuel B; Marker, Arwen M; Lourenco, Stella F

    2017-01-01

    The current study investigated individual differences in the flexibility of peripersonal space (i.e., representational space near the body), specifically in relation to trait claustrophobic fear (i.e., fear of suffocating or being physically restricted). Participants completed a line bisection task with either a laser pointer (Laser condition), allowing for a baseline measure of the size of one's peripersonal space, or a stick (Stick condition), which produces expansion of one's peripersonal space. Our results revealed that individuals high in claustrophobic fear had larger peripersonal spaces than those lower in claustrophobic fear, replicating previous research. We also found that, whereas individuals low in claustrophobic fear demonstrated the expected expansion of peripersonal space in the Stick condition, individuals high in claustrophobic fear showed less expansion, suggesting decreased flexibility. We discuss these findings in relation to the defensive function of peripersonal space and reduced attentional flexibility associated with trait anxieties.

  9. Slip-stick excitation and travelling waves excite silo honking

    NASA Astrophysics Data System (ADS)

    Warburton, Katarzyna; Porte, Elze; Vriend, Nathalie

    2017-06-01

    Silo honking is the harmonic sound generated by the discharge of a silo filled with a granular material. In industrial storage silos, the acoustic emission during discharge of PET-particles forms a nuisance for the environment and may ultimately result in structural failure. This work investigates the phenomenon experimentally using a laboratory-scale silo, and successfully correlates the frequency of the emitted sound with the periodicity of the mechanical motion of the grains. The key driver is the slip-stick interaction between the wall and the particles, characterized as a wave moving upwards through the silo. A quantitative correlation is established for the first time between the frequency of the sound, measured with an electret microphone, and the slip-frequency, measured with a high-speed camera. In the lower regions of the tube, both the slip-stick motion and the honking sound disappear.

  10. Hockey-stick steam generator for LMFBR

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hallinan, G.J.; Svedlund, P.E.

    1981-01-01

    This paper presents the criteria and evaluation leading to the selection of the Hockey Stick Steam Generator Concept and subsequent development of that concept for LMFBR application. The selection process and development of the Modular Steam Generator (MSG) is discussed, including the extensive test programs that culminated in the manufacture and test of a 35 MW(t) Steam Generator. The design of the CRBRP Steam Generator is described, emphasizing the current status and a review of the critical structural areas. CRBRP steam generator development tests are evaluated, with a discussion of test objectives and rating of the usefulness of test resultsmore » to the CRBRP prototype design. Manufacturing experience and status of the CRBRP prototype and plant units is covered. The scaleup of the Hockey Stick concept to large commercial plant application is presented, with an evaluation of scaleup limitations, transient effects, and system design implications.« less

  11. Chemical characterization of biomass fuel smoke particles of rural kitchens of South Asia

    NASA Astrophysics Data System (ADS)

    Deka, Pratibha; Hoque, Raza Rafiqul

    2015-05-01

    Biomass fuel smoke particles (BFSPs) of rural kitchens collected during dry and wet seasons were characterized for elements, anions and carbon. The BFSPs of kitchens using varied biomass fuel types viz. cow dung stick, mixed biomass, cow-dung stick-mixed biomass and sugarcane bagasse were chosen for the study. The BFSPs from cow dung fuel stick showed higher levels of elements, anions and particulate carbon than other BFSPs. Calcium, K, Fe and Mg were the major elements found in all BFSPs, which did not vary much between the seasons. Sulphate was found to be the dominant anion present in all BFSPs followed by Clˉ and PO43-. Seasonal variation was pronounced in the case of abundance of anions and particulate carbon. The ratio OC/EC, often used as source signature of biomass burning, was found to be within 1.89-7.41 and 1.72-6.19 during dry and wet seasons respectively.

  12. On the micromechanics of slip events in sheared, fluid-saturated fault gouge

    NASA Astrophysics Data System (ADS)

    Dorostkar, Omid; Guyer, Robert A.; Johnson, Paul A.; Marone, Chris; Carmeliet, Jan

    2017-06-01

    We used a three-dimensional discrete element method coupled with computational fluid dynamics to study the poromechanical properties of dry and fluid-saturated granular fault gouge. The granular layer was sheared under dry conditions to establish a steady state condition of stick-slip dynamic failure, and then fluid was introduced to study its effect on subsequent failure events. The fluid-saturated case showed increased stick-slip recurrence time and larger slip events compared to the dry case. Particle motion induces fluid flow with local pressure variation, which in turn leads to high particle kinetic energy during slip due to increased drag forces from fluid on particles. The presence of fluid during the stick phase of loading promotes a more stable configuration evidenced by higher particle coordination number. Our coupled fluid-particle simulations provide grain-scale information that improves understanding of slip instabilities and illuminates details of phenomenological, macroscale observations.

  13. Volcanic ash melting under conditions relevant to ash turbine interactions.

    PubMed

    Song, Wenjia; Lavallée, Yan; Hess, Kai-Uwe; Kueppers, Ulrich; Cimarelli, Corrado; Dingwell, Donald B

    2016-03-02

    The ingestion of volcanic ash by jet engines is widely recognized as a potentially fatal hazard for aircraft operation. The high temperatures (1,200-2,000 °C) typical of jet engines exacerbate the impact of ash by provoking its melting and sticking to turbine parts. Estimation of this potential hazard is complicated by the fact that chemical composition, which affects the temperature at which volcanic ash becomes liquid, can vary widely amongst volcanoes. Here, based on experiments, we parameterize ash behaviour and develop a model to predict melting and sticking conditions for its global compositional range. The results of our experiments confirm that the common use of sand or dust proxy is wholly inadequate for the prediction of the behaviour of volcanic ash, leading to overestimates of sticking temperature and thus severe underestimates of the thermal hazard. Our model can be used to assess the deposition probability of volcanic ash in jet engines.

  14. Design considerations of manipulator and feel system characteristics in roll tracking

    NASA Technical Reports Server (NTRS)

    Johnston, Donald E.; Aponso, Bimal L.

    1988-01-01

    A fixed-base simulation was performed to identify and quantify interactions between the pilot's hand/arm neuromuscular subsystem and such control system features of typical modern fighter aircraft roll rate command mechanizations as: (1) force versus displacement sensing side-stick type manipulator, (2) feel force/displacement gradient, (3) feel system versus command prefilter dynamic lag, and (4) flight control system effective time delay. The experiment encompassed some 48 manipulator/filter/aircraft configurations. Displacement side-stick experiment results are given and compared with the previous force sidestick experiment results. Attention is focused on control bandwidth, excitement (peaking) of the neuromuscular mode, feel force/displacement gradient effects, time delay effects, etc. Section 5 is devoted to experiments with a center-stick in which force versus displacement sensing, feel system lag, and command prefilter lag influences on tracking performance and pilot preference are investigated.

  15. New lumped-mass-stick model based on modal characteristics of structures: development and application to a nuclear containment building

    NASA Astrophysics Data System (ADS)

    Roh, Hwasung; Lee, Huseok; Lee, Jong Seh

    2013-06-01

    In this study, a new lumped-mass-stick model (LMSM) is developed based on the modal characteristics of a structure such as eigenvalues and eigenvectors. The simplified model, named the "frequency adaptive lumped-massstick model," hasonly a small number of stick elements and nodes to provide the same natural frequencies of the structure and is applied to a nuclear containment building. To investigate the numerical performance of the LMSM, a time history analysis is carried out on both the LMSM and the finite element model (FEM) for a nuclear containment building. A comparison of the results shows that the dynamic responses of the LMSM in terms of displacement and acceleration are almost identical to those of the FEM. In addition, the results in terms of fl oor response spectra at certain elevations are also in good agreement.

  16. Aerodynamic penalties of heavy rain on a landing aircraft

    NASA Technical Reports Server (NTRS)

    Haines, P. A.; Luers, J. K.

    1982-01-01

    The aerodynamic penalties of very heavy rain on landing aircraft were investigated. Based on severity and frequency of occurrence, the rainfall rates of 100 mm/hr, 500 mm/hr, and 2000 mm/hr were designated, respectively, as heavy, severe, and incredible. The overall and local collection efficiencies of an aircraft encountering these rains were calculated. The analysis was based on raindrop trajectories in potential flow about an aircraft. All raindrops impinging on the aircraft are assumed to take on its speed. The momentum loss from the rain impact was later used in a landing simulation program. The local collection efficiency was used in estimating the aerodynamic roughness of an aircraft in heavy rain. The drag increase from this roughness was calculated. A number of landing simulations under a fixed stick assumption were done. Serious landing shortfalls were found for either momentum or drag penalties and especially large shortfalls for the combination of both. The latter shortfalls are comparable to those found for severe wind shear conditions.

  17. Effects of anisotropic conduction and heat pipe interaction on minimum mass space radiators

    NASA Technical Reports Server (NTRS)

    Baker, Karl W.; Lund, Kurt O.

    1991-01-01

    Equations are formulated for the two dimensional, anisotropic conduction of heat in space radiator fins. The transverse temperature field was obtained by the integral method, and the axial field by numerical integration. A shape factor, defined for the axial boundary condition, simplifies the analysis and renders the results applicable to general heat pipe/conduction fin interface designs. The thermal results are summarized in terms of the fin efficiency, a radiation/axial conductance number, and a transverse conductance surface Biot number. These relations, together with those for mass distribution between fins and heat pipes, were used in predicting the minimum radiator mass for fixed thermal properties and fin efficiency. This mass is found to decrease monotonically with increasing fin conductivity. Sensitivities of the minimum mass designs to the problem parameters are determined.

  18. Correlations of catalytic combustor performance parameters

    NASA Technical Reports Server (NTRS)

    Bulzan, D. L.

    1978-01-01

    Correlations for combustion efficiency percentage drop and the minimum required adiabatic reaction temperature necessary to meet emissions goals of 13.6 g CO/kg fuel and 1.64 g HC/kg fuel are presented. Combustion efficiency was found to be a function of the cell density, cell circumference, reactor length, reference velocity, and adiabatic reaction temperature. The percentage pressure drop at an adiabatic reaction temperature of 1450 K was found to be proportional to the reference velocity to the 1.5 power and to the reactor length. It is inversely proportional to the pressure, cell hydraulic diameter, and fractional open area. The minimum required adiabatic reaction temperature was found to increase with reference velocity and decrease with cell circumference, cell density and reactor length. A catalyst factor was introduced into the correlations to account for differences between catalysts. Combustion efficiency, the percentage pressure drop, and the minimum required adiabatic reaction temperature were found to be a function of the catalyst factor. The data was from a 12 cm-diameter test rig with noble metal reactors using propane fuel at an inlet temperature of 800 K.

  19. Colloid transport in saturated porous media: Elimination of attachment efficiency in a new colloid transport model

    USGS Publications Warehouse

    Landkamer, Lee L.; Harvey, Ronald W.; Scheibe, Timothy D.; Ryan, Joseph N.

    2013-01-01

    A colloid transport model is introduced that is conceptually simple yet captures the essential features of colloid transport and retention in saturated porous media when colloid retention is dominated by the secondary minimum because an electrostatic barrier inhibits substantial deposition in the primary minimum. This model is based on conventional colloid filtration theory (CFT) but eliminates the empirical concept of attachment efficiency. The colloid deposition rate is computed directly from CFT by assuming all predicted interceptions of colloids by collectors result in at least temporary deposition in the secondary minimum. Also, a new paradigm for colloid re-entrainment based on colloid population heterogeneity is introduced. To accomplish this, the initial colloid population is divided into two fractions. One fraction, by virtue of physiochemical characteristics (e.g., size and charge), will always be re-entrained after capture in a secondary minimum. The remaining fraction of colloids, again as a result of physiochemical characteristics, will be retained “irreversibly” when captured by a secondary minimum. Assuming the dispersion coefficient can be estimated from tracer behavior, this model has only two fitting parameters: (1) the fraction of the initial colloid population that will be retained “irreversibly” upon interception by a secondary minimum, and (2) the rate at which reversibly retained colloids leave the secondary minimum. These two parameters were correlated to the depth of the Derjaguin-Landau-Verwey-Overbeek (DLVO) secondary energy minimum and pore-water velocity, two physical forces that influence colloid transport. Given this correlation, the model serves as a heuristic tool for exploring the influence of physical parameters such as surface potential and fluid velocity on colloid transport.

  20. Safe and consistent method of spot-welding platinum thermocouple wires and foils for high temperature measurements.

    PubMed

    Orr, G; Roth, M

    2012-08-01

    A low-voltage (mV) electronically triggered spot welding system for fabricating fine thermocouples and thin sheets used in high-temperature characterization of materials' properties is suggested. The system is based on the capacitance discharge method with a timed trigger for obtaining reliable and consistent welds. In contrast to existing techniques based on employing high voltage DC supplies for charging the capacitor or supplies with positive and negative rails, this method uses a simple, standard dual power supply available at most of the physical laboratories or can be acquired at a low cost. In addition, an efficient and simple method of fabricating non-sticking electrodes that do not contaminate the weld area is suggested and implemented.

  1. Dust coagulation. [in interstellar medium observed in stellar envelopes and planetary disks

    NASA Technical Reports Server (NTRS)

    Chokshi, Arati; Tielens, A. G. G. M.; Hollenbach, D.

    1993-01-01

    The microphysics of coagulation between two, colliding, smooth, spherical grains in the elastic limit is investigated, and the criteria for sticking as a function of particle sizes, collision velocities, elastic properties, and binding energy are calculated. Critical relative velocities for coagulation were evaluated as a function of grain sizes for solicate, icy, and carbonaceous grains. It is concluded that efficient coagulation requires coverage of grain cores by an icy grain mantle. In this case, coagulation leads to only a doubling of the mass of a large grain within a dense core lifetime. It is concluded that coagulation can have a dramatic effect on the visible and, particularly, the UV portion of the extinction curve in dense clouds and on their IR spectrum.

  2. Inverted bulk-heterojunction solar cell with cross-linked hole-blocking layer

    PubMed Central

    Udum, Yasemin; Denk, Patrick; Adam, Getachew; Apaydin, Dogukan H.; Nevosad, Andreas; Teichert, Christian; S. White, Matthew.; S. Sariciftci, Niyazi.; Scharber, Markus C.

    2014-01-01

    We have developed a hole-blocking layer for bulk-heterojunction solar cells based on cross-linked polyethylenimine (PEI). We tested five different ether-based cross-linkers and found that all of them give comparable solar cell efficiencies. The initial idea that a cross-linked layer is more solvent resistant compared to a pristine PEI layer could not be confirmed. With and without cross-linking, the PEI layer sticks very well to the surface of the indium–tin–oxide electrode and cannot be removed by solvents used to process PEI or common organic semiconductors. The cross-linked PEI hole-blocking layer functions for multiple donor–acceptor blends. We found that using cross-linkers improves the reproducibility of the device fabrication process. PMID:24817837

  3. Innovation Incubator: Whisker Labs Technical Evaluation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sparn, Bethany F.; Frank, Stephen M.; Earle, Lieko

    The Wells Fargo Innovation Incubator (IN2) is a program to foster and accelerate startup companies with commercial building energy-efficiency and demand management technologies. The program is funded by the Wells Fargo Foundation and co-administered by the National Renewable Energy Laboratory (NREL). Whisker Labs, an Oakland, California-based company, was one of four awardees in the first IN2 cohort and was invited to participate in the program because of its novel electrical power sensing technology for circuit breakers. The stick-on Whisker meters install directly on the front face of the circuit breakers in an electrical panel using adhesive, eliminating the need tomore » open the panel and install current transducers (CTs) on the circuit wiring.« less

  4. New measurements of the sticking coefficient and binding energy of molecules on non-porous amorphous solid water in the submonolayer regime

    NASA Astrophysics Data System (ADS)

    He, Jiao; Acharyya, Kinsuk; Emtiaz, S. M.; Vidali, Gianfranco

    2016-06-01

    Sticking and adsorption of molecules on dust grains are two important processes in gas-grain interactions. We accurately measured both the sticking coefficient and the binding energy of several key molecules on the surface of amorphous solid water as a function of coverage.A time-resolved scattering technique was used to measure sticking coefficient of H2, D2, N2, O2, CO, CH4, and CO2 on non-porous amorphous solid water (np-ASW) in the low coverage limit over a wide range of surface temperatures. We found that the time-resolved scattering technique is advantageous over the conventional King-Wells method that underestimates the sticking coefficient. Based on the measured values we suggest a useful general formula of the sticking coefficient as a function of grain temperature and molecule-surface binding energy.We measured the binding energy of N2, CO, O2, CH4, and CO2 on np-ASW, and of N2 and CO on porous amorphous solid water (p-ASW). We were able to measure binding energies down to a fraction of 1% of a layer, thus making these measurements more appropriate for astrochemistry than the existing values. We found that CO2 forms clusters on np-ASW surface even at very low coverage; this may help in explaining the segregation of CO2 in ices. The binding energies of N2, CO, O2, and CH4 on np-ASW decrease with coverage in the submonolayer regime. Their values in the low coverage limit are much higher than what is commonly used in gas-grain models. An empirical formula was used to describe the coverage dependence of the binding energies. We used the newly determined binding energy distributions in a simulation of gas-grain chemistry for cold dense clouds and hot core models. We found that owing to the higher value of desorption energy in the sub-monlayer regime a fraction of all these ices stays much longer and to higher temperature on the grain surface compared to the case using single value energies as currently done in astrochemical models.This work was supported in part by a grant to GV from NSF --- Astronomy & Astrophysics Division (#1311958)

  5. Quality analysis, miceller behavior, and environmental impact of some laundry detergents available in Bangladesh.

    PubMed

    Nur-E-Alam, M; Islam, M Monirul; Islam, M Nazrul; Rima, Farhana Rahman; Islam, M Nurul

    2016-03-01

    The cleansing efficiencies of laundry detergents depend on composition and variation of ingredients such as surfactants, phosphate, and co-builders. Among these ingredients, surfactants and phosphate are considered as hazardous materials. Knowledge on compositions and micellar behavior is very useful for understanding their cleansing efficiencies and environmental impact. With this view, composition, critical micelle concentration, and dissolved oxygen level in aqueous solution of some laundry detergents available in Bangladesh such as keya, Wheel Power White, Tibet, Surf Excel, and Chaka were determined. Surfactant and phosphate were found to be maximum in Surf Excel and Wheel Power White, respectively, while both of the ingredients were found to be minimum in Tibet. The critical micelle concentration decreased with increasing surfactant content. The amount of laundry detergents required for efficient cleansing was found to be minimum for Surf Excel and maximum for Chaka; however, cleansing cost was the highest for Surf Excel and the lowest for Tibet. The maximum amount of surfactants and phosphate was discharged by Surf Excel and Wheel Power White, respectively, while discharges of both of the ingredients were minimum for Tibet. The maximum decrease of dissolved oxygen level was caused by Surf Excel and the minimum by Tibet. Therefore, it can be concluded that Tibet is cost-effective and environment friendly, whereas Surf Excel and Wheel Power White are expensive and pose a threat to water environment.

  6. Limited Investigation of Active Feel Control Stick System (Active Stick)

    DTIC Science & Technology

    2009-06-01

    contained no limit protection and was the baseline system. The second system was “F-16 like” and contained angle -of-attack and load factor limiting...system. The second system was “F-16 like” and contained angle of attack (AOA) and load factor limiting features built into the flight control system...Force PTI at VLO .......................... 13 Figure 9: Pitch Angle Response to 1.5 g Commanded Force PTI at VLO ........................ 14 Figure 10

  7. Wood content of stacked 4-foot round pulpwood in Connecticut

    Treesearch

    R. H. Fenton

    1948-01-01

    Buying wood stacked in 4-foot lengths is sometimes like buying a pig in a poke. A cord is simply a pile 4 by 4 by 8 feet, or 128 cubic feet. Even though wood piled this way may stack up to the specified dimensions, the actual mount of wood in the pile may vary greatly. The species, the size of the sticks, the thickness of the bark, the crookedness of the sticks, and...

  8. The effect of mango and neem extract on four organisms causing dental caries: Streptococcus mutans, Streptococcus salivavius, Streptococcus mitis, and Streptococcus sanguis: an in vitro study.

    PubMed

    Prashant, G M; Chandu, G N; Murulikrishna, K S; Shafiulla, M D

    2007-01-01

    Chewing twigs of the mango or neem tree is a common way of cleaning the teeth in the rural and semi-urban population. These twigs are also believed to possess medicinal properties. The present study was conducted to evaluate the antimicrobial effects of these chewing sticks on the microorganisms Streptococcus mutans , Streptococcus salivarius , Streptococcus mitis , and Streptococcus sanguis which are involved in the development of dental caries. An additional objective was to identify an inexpensive, simple, and effective method of preventing and controlling dental caries. The sticks were sun dried, ground into a coarse powder, and weighed into 5 gm, 10 gm, and 50 gm amounts. These were added to 100 ml of deionized distilled water. After soaking for 48 h at 4 degrees C, the water was filtered. The filtrate was inoculated onto blood agar plates containing individual species of microorganisms and incubated at 37 degrees C for 48 h. Mango extract, at 50% concentration, showed maximum zone of inhibition on Streptococcus mitis . Neem extract produced the maximum zone of inhibition on Streptococcus mutans at 50% concentration. Even at 5% concentration neem extract showed some inhibition of growth for all the four species of organisms. A combination of neem and mango chewing sticks may provide the maximum benefit. We recommend the use of both the chewing sticks.

  9. Smart walking stick for blind people: an application of 3D printer

    NASA Astrophysics Data System (ADS)

    Ikbal, Md. Allama; Rahman, Faidur; Ali, Md. Ripon; Kabir, M. Hasnat; Furukawa, Hidemitsu

    2017-04-01

    A prototype of the smart walking stick has been designed and characterized for the people who are visually impaired. In this study, it was considered that the proposed system will alert visuallyimpaired people over the obstacles which are in front of blind people as well as the obstacles of the street such as a manhole, when the blind people are walking in the street. The proposed system was designed in two stages, i.e. hardware and software which makes the system as a complete prototype. Three ultrasonic sonar sensors were used to detect in front obstacle and street surface obstacle such as manhole. Basically the sensor transmits an electromagnetic wave which travels toward the obstacle and back to the sensor receiver. The distance between the sensor and the obstacle is calculated from the received signal. The calculated distance value is compared with the pre-defined value and determines whether the obstacle is present or not. The 3D CAD software was used to design the sensor holder. An Up-Mini 3D printer was used to print the sensor holders which were mounted on the walking stick. Therefore, the sensors were fixed in the right position. Another sensor was used for the detecting the water on the walking street. The performance for detecting the obstacles and water indicate the merit of smart walking stick.

  10. Infrared dynamics of cold atoms on hot graphene membranes

    NASA Astrophysics Data System (ADS)

    Sengupta, Sanghita; Kotov, Valeri N.; Clougherty, Dennis P.

    2016-06-01

    We study the infrared dynamics of low-energy atoms interacting with a sample of suspended graphene at finite temperature. The dynamics exhibits severe infrared divergences order by order in perturbation theory as a result of the singular nature of low-energy flexural phonon emission. Our model can be viewed as a two-channel generalization of the independent boson model with asymmetric atom-phonon coupling. This allows us to take advantage of the exact nonperturbative solution of the independent boson model in the stronger channel while treating the weaker one perturbatively. In the low-energy limit, the exact solution can be viewed as a resummation (exponentiation) of the most divergent diagrams in the perturbative expansion. As a result of this procedure, we obtain the atom's Green function which we use to calculate the atom damping rate, a quantity equal to the quantum sticking rate. A characteristic feature of our results is that the Green's function retains a weak, infrared cutoff dependence that reflects the reduced dimensionality of the problem. As a consequence, we predict a measurable dependence of the sticking rate on graphene sample size. We provide detailed predictions for the sticking rate of atomic hydrogen as a function of temperature and sample size. The resummation yields an enhanced sticking rate relative to the conventional Fermi golden rule result (equivalent to the one-loop atom self-energy), as higher-order processes increase damping at finite temperature.

  11. An Investigation of the Mechanics and Sticking Region of a One-Repetition Maximum Close-Grip Bench Press versus the Traditional Bench Press

    PubMed Central

    Lockie, Robert G.; Callaghan, Samuel J.; Moreno, Matthew R.; Risso, Fabrice G.; Liu, Tricia M.; Stage, Alyssa A.; Birmingham-Babauta, Samantha A.; Stokes, John J.; Giuliano, Dominic V.; Lazar, Adrina; Davis, DeShaun L.; Orjalo, Ashley J.

    2017-01-01

    The close-grip bench press (CGBP) is a variation of the traditional bench press (TBP) that uses a narrower grip (~95% of biacromial distance (BAD)) and has potential application for athletes performing explosive arm actions from positions where the hands are held close to the torso. Limited research has investigated CGBP mechanics compared to the TBP. Twenty-seven resistance-trained individuals completed a one-repetition maximum TBP and CGBP. The TBP was performed with the preferred grip; the CGBP with a grip width of 95% BAD. A linear position transducer measured lift distance and duration; peak and mean power, velocity, and force; distance and time when peak power occurred; and work. Pre-sticking region (PrSR), sticking region, and post-sticking region distance and duration for each lift was measured. A repeated measures ANOVA was used to derive differences between TBP and CGBP mechanics (p < 0.01); effect sizes (d) were also calculated. A greater load was lifted in the TBP, thus mean force was greater (d = 0.16–0.17). Peak power and velocity were higher in the CGBP, which had a longer PrSR distance (d = 0.49–1.32). The CGBP could emphasize power for athletes that initiate explosive upper-body actions with the hands positioned close to the torso.

  12. Impact of Rate Design Alternatives on Residential Solar Customer Bills: Increased Fixed Charges, Minimum Bills and Demand-Based Rates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McLaren, Joyce; Davidson, Carolyn; Miller, John

    Utilities are proposing changes to residential rate structures to address concerns about lost revenue due to increased adoption of distributed solar generation. An investigation of the impacts of increased fixed charges, minimum bills and residential demand charges on PV and non-PV customer bills suggests that minimum bills more accurately capture utilities' revenue requirement than fixed charges, while not acting as a disincentive to efficiency or negatively impacting low-income customers.

  13. 49 CFR 179.300-6 - Thickness of plates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ....037 Where: d = inside diameter in inches; E = 1.0 welded joint efficiency; P = minimum required bursting pressure in psig; S = minimum tensile strength of plate material in p.s.i. as prescribed in § 179... −d 2) where: d = inside diameter in inches; D = outside diameter in inches; p = tank test pressure in...

  14. Numerical Design of Megawatt Gyrotron with 120 GHz Frequency and 50% Efficiency for Plasma Fusion Application

    NASA Astrophysics Data System (ADS)

    Kumar, Nitin; Singh, Udaybir; Kumar, Anil; Bhattacharya, Ranajoy; Singh, T. P.; Sinha, A. K.

    2013-02-01

    The design of 120 GHz, 1 MW gyrotron for plasma fusion application is presented in this paper. The mode selection is carried out considering the aim of minimum mode competition, minimum cavity wall heating, etc. On the basis of the selected operating mode, the interaction cavity design and beam-wave interaction computation are carried out by using the PIC code. The design of triode type Magnetron Injection Gun (MIG) is also presented. Trajectory code EGUN, synthesis code MIGSYN and data analysis code MIGANS are used in the MIG designing. Further, the design of MIG is also validated by using the another trajectory code TRAK. The design results of beam dumping system (collector) and RF window are also presented. Depressed collector is designed to enhance the overall tube efficiency. The design study confirms >1 MW output power with tube efficiency around 50% (with collector efficiency).

  15. Minimum energy efficiency standards for appliances: Old and new economic rationales

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Houde, Sebastien; Spurlock, C. Anna

    In this study, we revisit Hausman and Joskow (1982)'s economic rationales for appliance minimum energy efficiency standards. In addition to the four market failures they argued could justify appliance standards--energy prices below marginal social cost, consumers underestimating energy prices, consumer discount rates above social discount rates, or principal agent problems--we discuss two additional market failures that are relevant and potentially economically important in this context: market power and innovation market failures. We highlight puzzles uncovered by recent empirical results, and suggest directions future research should take to better understand the normative implications of appliance standards.

  16. Minimum energy efficiency standards for appliances: Old and new economic rationales

    DOE PAGES

    Houde, Sebastien; Spurlock, C. Anna

    2016-09-01

    In this study, we revisit Hausman and Joskow (1982)'s economic rationales for appliance minimum energy efficiency standards. In addition to the four market failures they argued could justify appliance standards--energy prices below marginal social cost, consumers underestimating energy prices, consumer discount rates above social discount rates, or principal agent problems--we discuss two additional market failures that are relevant and potentially economically important in this context: market power and innovation market failures. We highlight puzzles uncovered by recent empirical results, and suggest directions future research should take to better understand the normative implications of appliance standards.

  17. Methodology for the optimal design of an integrated first and second generation ethanol production plant combined with power cogeneration.

    PubMed

    Bechara, Rami; Gomez, Adrien; Saint-Antonin, Valérie; Schweitzer, Jean-Marc; Maréchal, François

    2016-08-01

    The application of methodologies for the optimal design of integrated processes has seen increased interest in literature. This article builds on previous works and applies a systematic methodology to an integrated first and second generation ethanol production plant with power cogeneration. The methodology breaks into process simulation, heat integration, thermo-economic evaluation, exergy efficiency vs. capital costs, multi-variable, evolutionary optimization, and process selection via profitability maximization. Optimization generated Pareto solutions with exergy efficiency ranging between 39.2% and 44.4% and capital costs from 210M$ to 390M$. The Net Present Value was positive for only two scenarios and for low efficiency, low hydrolysis points. The minimum cellulosic ethanol selling price was sought to obtain a maximum NPV of zero for high efficiency, high hydrolysis alternatives. The obtained optimal configuration presented maximum exergy efficiency, hydrolyzed bagasse fraction, capital costs and ethanol production rate, and minimum cooling water consumption and power production rate. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Both physical exercise and progressive muscle relaxation reduce the facing-the-viewer bias in biological motion perception.

    PubMed

    Heenan, Adam; Troje, Nikolaus F

    2014-01-01

    Biological motion stimuli, such as orthographically projected stick figure walkers, are ambiguous about their orientation in depth. The projection of a stick figure walker oriented towards the viewer, therefore, is the same as its projection when oriented away. Even though such figures are depth-ambiguous, however, observers tend to interpret them as facing towards them more often than facing away. Some have speculated that this facing-the-viewer bias may exist for sociobiological reasons: Mistaking another human as retreating when they are actually approaching could have more severe consequences than the opposite error. Implied in this hypothesis is that the facing-towards percept of biological motion stimuli is potentially more threatening. Measures of anxiety and the facing-the-viewer bias should therefore be related, as researchers have consistently found that anxious individuals display an attentional bias towards more threatening stimuli. The goal of this study was to assess whether physical exercise (Experiment 1) or an anxiety induction/reduction task (Experiment 2) would significantly affect facing-the-viewer biases. We hypothesized that both physical exercise and progressive muscle relaxation would decrease facing-the-viewer biases for full stick figure walkers, but not for bottom- or top-half-only human stimuli, as these carry less sociobiological relevance. On the other hand, we expected that the anxiety induction task (Experiment 2) would increase facing-the-viewer biases for full stick figure walkers only. In both experiments, participants completed anxiety questionnaires, exercised on a treadmill (Experiment 1) or performed an anxiety induction/reduction task (Experiment 2), and then immediately completed a perceptual task that allowed us to assess their facing-the-viewer bias. As hypothesized, we found that physical exercise and progressive muscle relaxation reduced facing-the-viewer biases for full stick figure walkers only. Our results provide further support that the facing-the-viewer bias for biological motion stimuli is related to the sociobiological relevance of such stimuli.

  19. The dissociative chemisorption of water on Ni(111): Mode- and bond-selective chemistry on metal surfaces

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Farjamnia, Azar; Jackson, Bret, E-mail: jackson@chem.umass.edu

    A fully quantum approach based on an expansion in vibrationally adiabatic eigenstates is used to explore the dissociative chemisorption of H{sub 2}O, HOD, and D{sub 2}O on Ni(111). For this late barrier system, excitation of both the bending and stretching modes significantly enhances dissociative sticking. The vibrational efficacies vary somewhat from mode-to-mode but are all relatively close to one, in contrast to methane dissociation, where the behavior is less statistical. Similar to methane dissociation, the motion of lattice atoms near the dissociating molecule can significantly modify the height of the barrier to dissociation, leading to a strong variation in dissociativemore » sticking with substrate temperature. Given a rescaling of the barrier height, our results are in reasonable agreement with measurements of the dissociative sticking of D{sub 2}O on Ni(111), for both laser-excited molecules with one or two quanta of excitation in the antisymmetric stretch and in the absence of laser excitation. Even without laser excitation, the beam contains vibrationally excited molecules populated at the experimental source temperature, and these make significant contributions to the sticking probability. At high collision energies, above the adiabatic barrier heights, our results correlate with these barrier heights and mode softening effects. At lower energies, dissociative sticking occurs primarily via vibrationally nonadiabatic pathways. We find a preference for O–H over O–D bond cleavage for ground state HOD molecules at all but the highest collision energies, and excitation of the O–H stretch gives close to 100% O–H selectivity at lower energies. Excitation of the O–D stretch gives a lower O–D cleavage selectivity, as the interaction with the surface leads to energy transfer from the O–D stretch into the O–H bond, when mode softening makes these vibrations nearly degenerate.« less

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Clausing, R.E.

    Results are summarized for an investigation of the sorption rates of gases on vapor-deposited titanium films. The usefulness of such films for ultrahigh speed vacuum pumping is appraised. The sorption of hydrogen, deuterium, oxygen, nitrogen, carbon monoxide, carbon dioxide, water vapor, helium, argon, and methane onto titanium films was measured for a variety of circumstances using techniques and apparatus developed for this specific purpose. The information obtained and techniques evolved in this study have shown that large-scale getter pumping is feasible and can be a very effective means of pumping many gases. Sticking fractions larger than 0.8 were obtained formore » hydrogen, deuterium, oxygen, nitrogen, carbon monoxide, and carbon dioxide. The experiments have shown that the sticking fraction for gases on vapor-deposited films is a function of the deposition conditions. There is strong evidence to support the supposition that conditions which favor the formation of a porous, fine-grained film structure with a large surface-to-volume ratio produce films with the highest sorption rates. The technique for measuring sticking fractions is new and in many respects unique. It utilizes a very large sorption surface, thus minimizing the perturbing effect of the instrumentation and evaporation apparatus and reducing the hazard of film contamination due to small leaks in the system or outgassing of system components. The method gives especially good accuracy for measurements of sticking fractions approaching unity. The quantity of gas adsorbed, the gas flux onto the getter surface, and the gas flux leaving the getter surface are measured directly. Any two of these three independent measurements can be used to determine the sticking fraction, thereby providing a means of checking the data. The evaporation techniques, substrate surface, and substrate area were chosen to very nearly duplicate the conditions likely to be encountered in the practical application of large-scale getter pumping. (auth)« less

  1. Needle Stick Injuries, Sharp Injuries and other Occupational Exposures to Blood and Body Fluids among Health Care Workers in a general hospital in Sarajevo, Bosnia and Herzegovina.

    PubMed

    Musa, Sanjin; Peek-Asa, Corinne; Young, Tracy; Jovanovic, Nina

    2014-01-01

    Health Professional exposures of health care workers (HCW) to potentially infective blood and body fluids presents a serious health threat, including hepatitis B, hepatitis C and HIV transmission. This study was conducted to assess the risk for and reporting of needle stick injuries, sharp injuries and other occupational exposures of health care workers in a large healthcare center in Sarajevo. This cross-sectional survey was conducted in May 2013. The study target population included all hospital health care workers who had a high potential for exposure. The estimated sample size was 48 physicians, 132 nurses/technicians and 30 auxiliary personnel. During their career, 124 (63.3%) HCW reported exposures to blood and body fluids. In total, needle stick injuries (66.1%) were the most common source of exposure, followed by contact with intact skin (12.1%) and cut with sharp object (11.3%). Only 43 (35.5%) reported any of these exposures to health authorities during their career. The odds of exposure to needle stick injuries and other occupational exposures to blood and bodily fluids were significantly higher among medical nurses/technicians (AOR=4.98, 95%CI=1.52-16,1) and auxiliary (AOR=4.30, 95% CI=1.07-17.34) personnel when compared to physicians. HCW in the operation room, intervention ambulance and laboratory (AOR=3.73, 95%CI=1.43-9.72) had higher odds of exposure than workers in the ambulatory departments. Needle stick Injuries, Sharp Injuries and other Occupational Exposures to Blood and Body Fluids among health care workers are underestimated hazard. Especially, for HCW who work in operation room/interventional ambulance. There is a need for preventive programs for HCW and further work on the establishment of an effective surveillance system.

  2. Both Physical Exercise and Progressive Muscle Relaxation Reduce the Facing-the-Viewer Bias in Biological Motion Perception

    PubMed Central

    Heenan, Adam; Troje, Nikolaus F.

    2014-01-01

    Biological motion stimuli, such as orthographically projected stick figure walkers, are ambiguous about their orientation in depth. The projection of a stick figure walker oriented towards the viewer, therefore, is the same as its projection when oriented away. Even though such figures are depth-ambiguous, however, observers tend to interpret them as facing towards them more often than facing away. Some have speculated that this facing-the-viewer bias may exist for sociobiological reasons: Mistaking another human as retreating when they are actually approaching could have more severe consequences than the opposite error. Implied in this hypothesis is that the facing-towards percept of biological motion stimuli is potentially more threatening. Measures of anxiety and the facing-the-viewer bias should therefore be related, as researchers have consistently found that anxious individuals display an attentional bias towards more threatening stimuli. The goal of this study was to assess whether physical exercise (Experiment 1) or an anxiety induction/reduction task (Experiment 2) would significantly affect facing-the-viewer biases. We hypothesized that both physical exercise and progressive muscle relaxation would decrease facing-the-viewer biases for full stick figure walkers, but not for bottom- or top-half-only human stimuli, as these carry less sociobiological relevance. On the other hand, we expected that the anxiety induction task (Experiment 2) would increase facing-the-viewer biases for full stick figure walkers only. In both experiments, participants completed anxiety questionnaires, exercised on a treadmill (Experiment 1) or performed an anxiety induction/reduction task (Experiment 2), and then immediately completed a perceptual task that allowed us to assess their facing-the-viewer bias. As hypothesized, we found that physical exercise and progressive muscle relaxation reduced facing-the-viewer biases for full stick figure walkers only. Our results provide further support that the facing-the-viewer bias for biological motion stimuli is related to the sociobiological relevance of such stimuli. PMID:24987956

  3. Validation of an optical encoder during free weight resistance movements and analysis of bench press sticking point power during fatigue.

    PubMed

    Drinkwater, Eric J; Galna, Brook; McKenna, Michael J; Hunt, Patrick H; Pyne, David B

    2007-05-01

    During the concentric movement of the bench press, there is an initial high-power push after chest contact, immediately followed by a characteristic area of low power, the so-called "sticking region." During high-intensity lifting, a decline in power can result in a failed lift attempt. The purpose of this study was to determine the validity of an optical encoder to measure power and then employ this device to determine power changes during the initial acceleration and sticking region during fatiguing repeated bench press training. Twelve subjects performed a free weight bench press, a Smith Machine back squat, and a Smith Machine 40-kg bench press throw for power validation measures. All barbell movements were simultaneously monitored using cinematography and an optical encoder. Eccentric and concentric mean and peak power were calculated using time and position data derived from each method. Validity of power measures between the video (criterion) and optical encoder scores were evaluated by standard error of the estimate (SEE) and coefficient of variation (CV). Seven subjects then performed 4 sets of 6 free weight bench press repetitions progressively increasing from 85 to 95% of their 6 repetition maximum, with each repetition continually monitored by an optical encoder. The SEE for power ranged from 3.6 to 14.4 W (CV, 1.0-3.0%; correlation, 0.97-1.00). During the free weight bench press training, peak power declined by approximately 55% (p < 0.01) during the initial acceleration phase of the final 2 repetitions of the final set. Although decreases in power of the sticking point were significant (p < 0.01), as early as repetition 5 (-40%) they reached critically low levels in the final 2 repetitions (>-95%). In conclusion, the optical encoder provided valid measures of kinetics during free weight resistance training movements. The decline in power during the initial acceleration phase appears a factor in a failed lift attempt at the sticking point.

  4. Research on design method of the full form ship with minimum thrust deduction factor

    NASA Astrophysics Data System (ADS)

    Zhang, Bao-ji; Miao, Ai-qin; Zhang, Zhu-xin

    2015-04-01

    In the preliminary design stage of the full form ships, in order to obtain a hull form with low resistance and maximum propulsion efficiency, an optimization design program for a full form ship with the minimum thrust deduction factor has been developed, which combined the potential flow theory and boundary layer theory with the optimization technique. In the optimization process, the Sequential Unconstrained Minimization Technique (SUMT) interior point method of Nonlinear Programming (NLP) was proposed with the minimum thrust deduction factor as the objective function. An appropriate displacement is a basic constraint condition, and the boundary layer separation is an additional one. The parameters of the hull form modification function are used as design variables. At last, the numerical optimization example for lines of after-body of 50000 DWT product oil tanker was provided, which indicated that the propulsion efficiency was improved distinctly by this optimal design method.

  5. Restoration of badlands through applying bio-engineering techniques in active gully systems: Evidence from the Ecuadorian Andes

    NASA Astrophysics Data System (ADS)

    Borja, P.; Vanacker, V.; Alvarado, D.; Govers, G.

    2012-04-01

    A better insight in the processes controlling sediment generation, transport and deposition in badlands is necessary to enhance restoration of degraded soils through eco-engineering techniques. In this study, we evaluate the effect of different bio-engineering measures on soil and slope stability. Five micro-catchments (of 0.2 to 5 ha) were selected within a 3 km2 area in the lower part of the Loreto catchment (Southern Ecuadorian Andes). The micro-catchments differ only by land cover and degree of implementation of soil and water conservation measures. Bio-engineering techniques were used to construct dikes made of fascines of wooden sticks and earth-filled tires in active gully beds, where they are most efficient to reduce water and sediment transport. The experimental design consists of three micro-catchments within highly degraded lands: (DI) micro-catchment with bio-engineering measures concentrated in the active gully beds, (DF) with reforestation of Eucalyptus trees, and (DT) reference situation without any conservation measures. Two micro-catchments were monitored in agricultural lands with (AI) and without (AT) bio-engineering measures in the active gully beds. All catchments were equipped with San Dimas flumes to measure water flow, and sediment traps to monitor sediment export. In the (active) gully beds, various parameters related to gully stability (soil water content, bed elevation, vegetation cover, sedimentation/erosion) were monitored at weekly intervals. First results show that bio-engineering techniques are efficient to stabilize active gully beds through a reduction of the rapid concentration of excess rainfall and the sediment production and transfer. Fascines made of wooden sticks are far more efficient than earth-filled tires. Sediment deposition behind dikes is strongly dependent on precedent rainfall events, and the slope and vegetation cover of the gully floor. The sediment deposited facilitates colonization of the gully floor by native grass and shrub species. Analyses of soil samples indicates that the soil moisture is significantly higher (and the bulk density lower) in the deposition zones within restored gullies compared to the reference situation. During rainfall events, the infiltration in the deposition zones becomes important. The increase in water availability in the gully floor permits grass seeds to germinate and shoot rapidly, which strongly enhances gully stabilization.

  6. Flying Qualities Design Requirements for Sidestick Controllers

    DTIC Science & Technology

    1979-10-01

    Harper vs wc - Fine Tracking 111 56. Cooper-Harper vs wc - Fine Tracking 111 57. Cooper-Harper ve wc - Landing 112 58. Cooper-Harper vs wc - Lending 112...c - Fine Tracking 119 62. Preference Rating vs wc - Fine Tracking 119 64. Preference Rating vs wc - Landing 120 65. Preference Rating vs w(c...a "fast airplane" to make up for the filtering effect of his arm and the stick. In fine tracking with a center stick the pilot will rest his arm

  7. Characterization and Fate of Gun and Rocket Propellant Residues on Testing and Training Ranges

    DTIC Science & Technology

    2011-08-01

    propellant sticks, is tied in three places with polyester and cotton thread ties. The bundle is then wrapped in lead foil (a de-coppering agent...sticks and the tying of the bundle in five places, again using polyester and cotton thread ties. The combustible case is manufactured mainly from...and brought back to DRDC to be weighed and extracted to measure the remaining 2,4-DNT. Most of what was collected was the remains of the cotton

  8. Xenon as a Neuroprotectant in Traumatic Brain Injury

    DTIC Science & Technology

    2012-03-01

    the animal is moving freely about a space), presence or absence of Head Tilt , and Baton (level of coordination used to grasp a stick with all four... Head Tilt (is it present?), and Baton (level of coordination used to grasp a stick with all four feet). Each category is scored on a scale of 0 to 5...the cortical surface, but no impact ensues. Blinding and allocation strategy : Experimental conditions (e.g., impact depth, gas etc) for any given day

  9. Status of Standardization Projects

    DTIC Science & Technology

    1991-12-31

    GL SA 50 SS N 8940 0729 MIL M 44203A MEATBALLS BF AND RICE GL F2 914 924 924 A GL SA 50 SS N 8940 0730 A A 20195 POTATO STICKS GL B4 A 921 922 921 G GL...8940 0729 MIL M 44203A MEATBALLS BF AND RICE GL F2 914 924 924 A GL SA 50 SS N 8940 0730 A A 20195 POTATO STICKS GL B4 A 921 922 921 G GL SA 50 SS U

  10. Enterobacter aerogenes Needle Stick Leads to Improved Biological Management System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johanson, Richard E.

    2004-08-01

    A laboratory worker who received a needle stick from a contaminated needle while working with a culture containing Enterobactor aerogenes developed a laboratory acquired infection. Although this organism has been shown to cause community and nosocomial infections, there have been no documented cases of a laboratory acquired infections. Lessons learned from the event led to corrective actions which included modification of lab procedures, development of a biological inventory tracking and risk identification system and the establishment of an effective biological safety program.

  11. Reversible non-stick behaviour of a bacterial protein polymer provides a tuneable molecular mimic for cell and tissue engineering.

    PubMed

    Roque, Ana I; Soliakov, Andrei; Birch, Mark A; Philips, Sion R; Shah, Deepan S H; Lakey, Jeremy H

    2014-05-01

    Yersina pestis, the bubonic plague bacterium, is coated with a polymeric protein hydrogel for protection from host defences. The protein, which is robust and non-stick, resembles structures found in many eukaryotic extracellular-matrix proteins. Cells grown on the natural polymer cannot adhere and grow poorly; however, when cell-adhesion motifs are inserted into the protein, the cells proliferate. © The Authors, 2014. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Ground Simulator Studies of the Effects of Valve Friction, Stick Friction, Flexibility, and Backwash on Power Control System Quality

    NASA Technical Reports Server (NTRS)

    Brown, B Porter

    1958-01-01

    Report presents results of tests made on a power control system by means of a ground simulator to determine the effects of various combinations of valve friction and stick friction on the ability of the pilot to control the system. Various friction conditions were simulated with a rigid control system, a flexible system, and a rigid system having some backlash. For the tests, the period and damping of the simulated airplane were held constant.

  13. DIF Detection Using Multiple-Group Categorical CFA with Minimum Free Baseline Approach

    ERIC Educational Resources Information Center

    Chang, Yu-Wei; Huang, Wei-Kang; Tsai, Rung-Ching

    2015-01-01

    The aim of this study is to assess the efficiency of using the multiple-group categorical confirmatory factor analysis (MCCFA) and the robust chi-square difference test in differential item functioning (DIF) detection for polytomous items under the minimum free baseline strategy. While testing for DIF items, despite the strong assumption that all…

  14. 77 FR 46034 - Utility Scale Wind Towers From the People's Republic of China: Preliminary Determination of Sales...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-02

    ... nacelle and rotor blades in a wind turbine with a minimum rated electrical power generation capacity in... efficiencies have been improving, and turbine heights have been rising to altitudes with much stronger winds... configurations that meet the minimum height requirement and are designed to support wind turbine electrical...

  15. Identification, rearing, and distribution of stick insects of Madeira Island: an example of raising biodiversity awareness.

    PubMed

    Aguiar, António M F; Pombo, Dora Aguin; Gonçalves, Ysabel M

    2014-04-10

    Two species of stick insects are currently known to be present in the Macaronesian archipelagos: Clonopsis gallica (Charpentier) (Phasmatodea: Bacillidae) on the Canary Islands and in the Azores and Carausius morosus (Sinéty) (Phasmatidae) in the Azores. Here, we provide the first reliable records of the presence and distribution of C. gallica and C. morosus on Madeira Island. Egg and adult stages are briefly described along with some notes on the life history of these species in captivity. Data on islandwide distribution are based on specimens donated by the public in response to an article published in a daily newspaper. This method of data collection raised great popular interest in stick insects. The role of newspapers as a means of communicating awareness in biodiversity issues is discussed. This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.

  16. Experimental Characterization of Hysteresis in a Revolute Joint for Precision Deployable Structures

    NASA Technical Reports Server (NTRS)

    Lake, Mark S.; Fung, Jimmy; Gloss, Kevin; Liechty, Derek S.

    1997-01-01

    Recent studies of the micro-dynamic behavior of a deployable telescope metering truss have identified instabilities in the equilibrium shape of the truss in response to low-energy dynamic loading. Analyses indicate that these micro-dynamic instabilities arise from stick-slip friction within the truss joints (e.g., hinges and latches). The present study characterizes the low-magnitude quasi-static load cycle response of the precision revolute joints incorporated in the deployable telescope metering truss, and specifically, the hysteretic response of these joints caused by stick-slip friction within the joint. Detailed descriptions are presented of the test setup and data reduction algorithms, including discussions of data-error sources and data-filtering techniques. Test results are presented from thirteen specimens, and the effects of joint preload and manufacturing tolerances are investigated. Using a simplified model of stick-slip friction, a relationship is made between joint load-cycle behavior and micro-dynamic dimensional instabilities in the deployable telescope metering truss.

  17. Numerical and flight simulator test of the flight deterioration concept

    NASA Technical Reports Server (NTRS)

    Mccarthy, J.; Norviel, V.

    1982-01-01

    Manned flight simulator response to theoretical wind shear profiles was studied in an effort to calibrate fixed-stick and pilot-in-the-loop numerical models of jet transport aircraft on approach to landing. Results of the study indicate that both fixed-stick and pilot-in-the-loop models overpredict the deleterious effects of aircraft approaches when compared to pilot performance in the manned simulator. Although the pilot-in-the-loop model does a better job than does the fixed-stick model, the study suggests that the pilot-in-the-loop model is suitable for use in meteorological predictions of adverse low-level wind shear along approach and departure courses to identify situations in which pilots may find difficulty. The model should not be used to predict the success or failure of a specific aircraft. It is suggested that the pilot model be used as part of a ground-based Doppler radar low-level wind shear detection and warning system.

  18. High-tensile strength sticking induced by ArF excimer laser surface treatment of poly(tetrafluoroethylene)

    NASA Astrophysics Data System (ADS)

    Hopp, Bela; Revesz, K.; Bor, Zsolt

    1998-07-01

    A successful enhancement of sticking of PTFE is demonstrated using ArF excimer laser irradiation in the presence of novel photoreagents. The applied laser fluence was very low at the sample - photoreagent liquid interface compared to the energy density applied in earlier investigations. After the treatment the PTFE films were glued by epoxy resin. It was found that at low doses the tensile strength of the sticking increased rapidly with the UV pulse number and the reached a saturation value, which was 6.66 MPa for triethylamine, 5.56 MPa in the case of 1,2-diaminoethane and 4.64 MPa for triethylene-tetramine. These are around two hundred times higher than the value of the untreated surface. It was found that this procedure makes the metallization and painting of PTFE surface also possible. A photoinduced electron transfer mechanism was suggested to describe the photoreaction, which is responsible for the increase of adhesion features on PTFE surface.

  19. Factors affecting the sticking of insects on modified aircraft wings

    NASA Technical Reports Server (NTRS)

    Yi, O.; Chitsaz-Z, M. R.; Eiss, N. S.; Wightman, J. P.

    1988-01-01

    Previous work showed that the total number of insects sticking to an aluminum surface was reduced by coating the aluminum surface with elastomers. Due to a large number of possible experimental errors, no correlation between the modulus of elasticity, the elastomer, and the total number of insects sticking to a given elastomer was obtained. One of the errors assumed to be introduced during the road test is a variable insect flux so the number of insects striking one surface might be different from that striking another sample. To eliminate this source of error, the road test used to collect insects was simulated in a laboratory by development of an insect impacting technique using a pipe and high pressure compressed air. The insects are accelerated by a compressed air gun to high velocities and are then impacted with a stationary target on which the sample is mounted. The velocity of an object exiting from the pipe was determined and further improvement of the technique was achieved to obtain a uniform air velocity distribution.

  20. Simultaneous neutron scattering and Raman scattering.

    PubMed

    Adams, Mark A; Parker, Stewart F; Fernandez-Alonso, Felix; Cutler, David J; Hodges, Christopher; King, Andrew

    2009-07-01

    The capability to make simultaneous neutron and Raman scattering measurements at temperatures between 1.5 and 450 K has been developed. The samples to be investigated are attached to one end of a custom-made center-stick suitable for insertion into a 100 mm-bore cryostat. The other end of the center-stick is fiber-optically coupled to a Renishaw in Via Raman spectrometer incorporating a 300 mW Toptica 785 nm wavelength stabilized diode laser. The final path for the laser beam is approximately 1.3 m in vacuo within the center-stick followed by a focusing lens close to the sample. Raman scattering measurements with a resolution of 1 to 4 cm(-1) can be made over a wide range (100-3200 cm(-1)) at the same time as a variety of different types of neutron scattering measurements. In this work we highlight the use of inelastic neutron scattering and neutron diffraction in conjunction with the Raman for studies of the globular protein lysozyme.

  1. Dissociative adsorption of O2 on unreconstructed metal (100) surfaces: Pathways, energetics, and sticking kinetics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Da-Jiang; Evans, James W.

    An accurate description of oxygen dissociation pathways and kinetics for various local adlayer environments is key for an understanding not just of the coverage dependence of oxygen sticking, but also of reactive steady states in oxidation reactions. Density functional theory analysis for M(100) surfaces with M=Pd, Rh, and Ni, where O prefers the fourfold hollow adsorption site, does not support the traditional Brundle-Behm-Barker picture of dissociative adsorption onto second-nearest-neighbor hollow sites with an additional blocking constraint. Rather adsorption via neighboring vicinal bridge sites dominates, although other pathways can be active. The same conclusion also applies for M=Pt and Ir, wheremore » oxygen prefers the bridge adsorption site. Statistical mechanical analysis is performed based on kinetic Monte Carlo simulation of a multisite lattice-gas model consistent with our revised picture of adsorption. This analysis determines the coverage and temperature dependence of sticking for a realistic treatment of the oxygen adlayer structure.« less

  2. Strong Temperature Dependence in the Reactivity of H 2 on RuO 2 (110)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Henderson, Michael A.; Dahal, Arjun; Dohnálek, Zdenek

    2016-08-04

    The ability of hydrogen to facilitate many types of heterogeneous catalysis starts with its adsorption. As such, understanding the temperature-dependence sticking of H2 is critical toward controlling and optimizing catalytic conditions in those cases where adsorption is rate-limiting. In this work, we examine the temperature-dependent sticking of H2/D2 to the clean RuO2(110) surface using the King & Wells molecular beam approach, temperature programmed desorption (TPD) and scanning tunneling microscopy (STM). We show that the sticking probability (molecular or dissociative) of H2/D2 on this surface is highly temperature-dependent, decreasing from ~0.4-0.5 below 25 K to effectively zero above 200 K. Bothmore » STM and TPD reveal that OH/OD formation is severely limited for adsorption temperatures above ~150 K. Previous literature reports of extensive surface hydroxylation from H2/D2 exposures at room temperature were most likely the result of inadvertent contamination brought about from dosing by chamber backfilling.« less

  3. Volcanic ash melting under conditions relevant to ash turbine interactions

    PubMed Central

    Song, Wenjia; Lavallée, Yan; Hess, Kai-Uwe; Kueppers, Ulrich; Cimarelli, Corrado; Dingwell, Donald B.

    2016-01-01

    The ingestion of volcanic ash by jet engines is widely recognized as a potentially fatal hazard for aircraft operation. The high temperatures (1,200–2,000 °C) typical of jet engines exacerbate the impact of ash by provoking its melting and sticking to turbine parts. Estimation of this potential hazard is complicated by the fact that chemical composition, which affects the temperature at which volcanic ash becomes liquid, can vary widely amongst volcanoes. Here, based on experiments, we parameterize ash behaviour and develop a model to predict melting and sticking conditions for its global compositional range. The results of our experiments confirm that the common use of sand or dust proxy is wholly inadequate for the prediction of the behaviour of volcanic ash, leading to overestimates of sticking temperature and thus severe underestimates of the thermal hazard. Our model can be used to assess the deposition probability of volcanic ash in jet engines. PMID:26931824

  4. Variational optical flow estimation based on stick tensor voting.

    PubMed

    Rashwan, Hatem A; Garcia, Miguel A; Puig, Domenec

    2013-07-01

    Variational optical flow techniques allow the estimation of flow fields from spatio-temporal derivatives. They are based on minimizing a functional that contains a data term and a regularization term. Recently, numerous approaches have been presented for improving the accuracy of the estimated flow fields. Among them, tensor voting has been shown to be particularly effective in the preservation of flow discontinuities. This paper presents an adaptation of the data term by using anisotropic stick tensor voting in order to gain robustness against noise and outliers with significantly lower computational cost than (full) tensor voting. In addition, an anisotropic complementary smoothness term depending on directional information estimated through stick tensor voting is utilized in order to preserve discontinuity capabilities of the estimated flow fields. Finally, a weighted non-local term that depends on both the estimated directional information and the occlusion state of pixels is integrated during the optimization process in order to denoise the final flow field. The proposed approach yields state-of-the-art results on the Middlebury benchmark.

  5. Construction of a dual axis force reflection stick and test station

    NASA Astrophysics Data System (ADS)

    Repperger, Daniel E.; Scarborough, Eric L.; Chelette, Tamara L.

    1991-11-01

    This report describes the construction of a dual axis force reflecting stick controller and test station which was constructed through the use of basic research funds (ILIR monies). The prototype described in this report is powered only by electric motors and used the latest technology in computers. This was an advancement over a previous prototype which involved pneumatic devices and was very large, bulky, and awkward to use. An experiment was conducted with 5 subjects as described herein to test the overall system for its use in experimental design. The motivation for developing such a small test station for the use of force reflection in stick controllers is because with this new compact and portable system, many new applications now appear for this technology. The system described herein minimizes both weight and electric power requirements to produce the same force reflection. By upgrading the technology in the components used in this test station, wider use of force reflection is now available for a host of new applications.

  6. Posterior consistency in conditional distribution estimation

    PubMed Central

    Pati, Debdeep; Dunson, David B.; Tokdar, Surya T.

    2014-01-01

    A wide variety of priors have been proposed for nonparametric Bayesian estimation of conditional distributions, and there is a clear need for theorems providing conditions on the prior for large support, as well as posterior consistency. Estimation of an uncountable collection of conditional distributions across different regions of the predictor space is a challenging problem, which differs in some important ways from density and mean regression estimation problems. Defining various topologies on the space of conditional distributions, we provide sufficient conditions for posterior consistency focusing on a broad class of priors formulated as predictor-dependent mixtures of Gaussian kernels. This theory is illustrated by showing that the conditions are satisfied for a class of generalized stick-breaking process mixtures in which the stick-breaking lengths are monotone, differentiable functions of a continuous stochastic process. We also provide a set of sufficient conditions for the case where stick-breaking lengths are predictor independent, such as those arising from a fixed Dirichlet process prior. PMID:25067858

  7. Aggregates: The Fundamental Building Blocks of Planetesimals?

    NASA Technical Reports Server (NTRS)

    Cuzzi, J. N.; Hartlep, T.; Simon, J. I.; Cato, M. J.

    2017-01-01

    The initial accretion of primitive asteroids (meteorite parent bodies) from freely-floating nebula particles remains problematic. Traditional growth-by-sticking models in turbulent nebulae encounter a formidable "meter-size barrier" due to both drift and destruction, or even a mmtocmsize "bouncing" barrier. Even if growth by sticking could somehow breach these barriers (perhaps if the actual sticking or strength is larger than current estimates, which are based on pure ice or pure silicate), turbulent nebulae present further obstacles through the 1-10km size range. On the other hand, nonturbulent nebulae form large asteroids too quickly to explain long spreads in formation times, or the dearth of melted asteroids. Thus, the intensity of nebula turbulence (or "alpha ") is critical to the entire process. Theoretical understanding of nebula turbulence continues to evolve; while recent models of MRI (magneticallydriven) turbulence favor lowornoturbulence environments, purely hydrodynamic turbulence is making a comeback with three recently discovered mechanisms generating turbulence of moderate which do not rely on magnetic fields at all.

  8. Generic Airplane Model Concept and Four Specific Models Developed for Use in Piloted Simulation Studies

    NASA Technical Reports Server (NTRS)

    Hoffler, Keith D.; Fears, Scott P.; Carzoo, Susan W.

    1997-01-01

    A generic airplane model concept was developed to allow configurations with various agility, performance, handling qualities, and pilot vehicle interface to be generated rapidly for piloted simulation studies. The simple concept allows stick shaping and various stick command types or modes to drive an airplane with both linear and nonlinear components. Output from the stick shaping goes to linear models or a series of linear models that can represent an entire flight envelope. The generic model also has provisions for control power limitations, a nonlinear feature. Therefore, departures from controlled flight are possible. Note that only loss of control is modeled, the generic airplane does not accurately model post departure phenomenon. The model concept is presented herein, along with four example airplanes. Agility was varied across the four example airplanes without altering specific excess energy or significantly altering handling qualities. A new feedback scheme to provide angle-of-attack cueing to the pilot, while using a pitch rate command system, was implemented and tested.

  9. A renormalization group model for the stick-slip behavior of faults

    NASA Technical Reports Server (NTRS)

    Smalley, R. F., Jr.; Turcotte, D. L.; Solla, S. A.

    1983-01-01

    A fault which is treated as an array of asperities with a prescribed statistical distribution of strengths is described. For a linear array the stress is transferred to a single adjacent asperity and for a two dimensional array to three ajacent asperities. It is shown that the solutions bifurcate at a critical applied stress. At stresses less than the critical stress virtually no asperities fail on a large scale and the fault is locked. At the critical stress the solution bifurcates and asperity failure cascades away from the nucleus of failure. It is found that the stick slip behavior of most faults can be attributed to the distribution of asperities on the fault. The observation of stick slip behavior on faults rather than stable sliding, why the observed level of seismicity on a locked fault is very small, and why the stress on a fault is less than that predicted by a standard value of the coefficient of friction are outlined.

  10. Jamming of three-dimensional prolate granular materials.

    PubMed

    Desmond, K; Franklin, Scott V

    2006-03-01

    We have found that the ability of long thin rods to jam into a solidlike state in response to a local perturbation depends upon both the particle aspect ratio and the container size. The dynamic phase diagram in this parameter space reveals a broad transition region separating granular stick-slip and solidlike behavior. In this transition region the pile displays both solid and stick-slip behavior. We measure the force on a small object pulled through the pile, and find the fluctuation spectra to have power law tails with an exponent characteristic of the region. The exponent varies from beta=-2 in the stick-slip region to beta=-1 in the solid region. These values reflect the different origins--granular rearrangements vs dry friction--of the fluctuations. Finally, the packing fraction shows only a slight dependence on container size, but depends on aspect ratio in a manner predicted by mean-field theory and implies an aspect-ratio-independent contact number of =5.25 +/- 0.03.

  11. Machinability of drilling T700/LT-03A carbon fiber reinforced plastic (CFRP) composite laminates using candle stick drill and multi-facet drill

    NASA Astrophysics Data System (ADS)

    Wang, Cheng-Dong; Qiu, Kun-Xian; Chen, Ming; Cai, Xiao-Jiang

    2015-03-01

    Carbon Fiber Reinforced Plastic (CFRP) composite laminates are widely used in aerospace and aircraft structural components due to their superior properties. However, they are regarded as difficult-to-cut materials because of bad surface quality and low productivity. Drilling is the most common hole making process for CFRP composite laminates and drilling induced delamination damage usually occurs severely at the exit side of drilling holes, which strongly deteriorate holes quality. In this work, the candle stick drill and multi-facet drill are employed to evaluate the machinability of drilling T700/LT-03A CFRP composite laminates in terms of thrust force, delamination, holes diameter and holes surface roughness. S/N ratio is used to characterize the thrust force while an ellipse-shaped delamination model is established to quantitatively analyze the delamination. The best combination of drilling parameters are determined by full consideration of S/N ratios of thrust force and the delamination. The results indicate that candle stick drill will induce the unexpected ellipse-shaped delamination even at its best drilling parameters of spindle speed of 10,000 rpm and feed rate of 0.004 mm/tooth. However, the multi-facet drill cutting at the relative lower feed rate of 0.004 mm/tooth and lower spindle speed of 6000 rpm can effectively prevent the delamination. Comprehensively, holes quality obtained by multi-facet drill is much more superior to those obtained by candle stick drill.

  12. Rapid detection of semenogelin by one-step immunochromatographic assay for semen identification.

    PubMed

    Sato, Itaru; Kojima, Koichiro; Yamasaki, Tadashi; Yoshida, Kaoru; Yoshiike, Miki; Takano, Shoichi; Mukai, Toshiji; Iwamoto, Teruaki

    2004-04-01

    To identify semen in forensic samples, we developed an analytical system for one-step immunoassay that has been constructed using the concept of immunochromatography and can identify semenogelin (Sg), which originates in the seminal vesicles. The system employed monoclonal antibody (mAb) and polyclonal antibody (pAb) against recombinant Sg-II (63 kDa), which has been synthesized in insect cells using baculovirus. The two antibodies bound with the seminal plasma motility inhibitor (SPMI; 14 kDa) as a final fragment peptide of Sg. The test stick is based on the sandwich technique using the above antibodies. When serial dilutions of seminal plasma were analyzed using this test stick, the intensity of a clear immunoreactive signal peaked at 2000-fold dilution. Thereafter, the signals decreased slowly but still persisted up to 400,000-fold dilution. The Sg antigen was undetectable in saliva, urine, breast milk, serum or vaginal secretions. Also, the test stick shown did not react with animal semen samples, such as those from horses, dogs, swine and bulls. When semen samples, diluted 100,000-fold from 100 men were tested, the Sg antigenic activity was detectable in all samples. In addition, the specificity and sensitivity of the test stick for identification of semen were demonstrated by comparative forensic studies. We conclude that this immunoassay method is a useful confirmatory test for the identification of semen. The immunochromatographic system for forensic testing or research use will become available commercially soon.

  13. Cigarette price level and variation in five Southeast Asian countries.

    PubMed

    Liber, Alex C; Ross, Hana; Ratanachena, Sophapan; Dorotheo, E Ulysses; Foong, Kin

    2015-06-01

    To monitor and analyse impacts of the interaction between tobacco excise tax policy and industry price strategy, on the price level and variation of cigarettes sold in five Southeast Asian countries (Indonesia, Cambodia, Lao PDR, the Philippines and Vietnam). Prices of cigarette sold by sticks and packs were collected through an in-person survey of retailers during 2011. Mean cigarette prices and price variation were calculated in each study country for single cigarettes, whole packs and brand groups. Price variation of whole packs was greater in countries with ad-valorem excise tax structures (Cambodia, Lao PDR and Vietnam) than in countries with multitiered specific excise taxes (Indonesia and the Philippines). The price variation for single sticks appeared to be driven by local currency denomination. Cigarettes sold individually cost more per stick than cigarettes sold in whole packs in every brand group except for Indonesia's domestic brands. Tobacco industry strategy and excise tax structure drove the price level and variation of cigarettes sold in packs, while currency denominations influence the selling price of single sticks. To maximise the effectiveness of tobacco tax policies, countries should adopt specific excise tax structures to decrease cigarette price variation, which would minimise opportunities for smokers to 'trade down' to a cheaper brand to avoid a tax-driven price increase. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  14. Validation of a new scale to assess olfactory dysfunction in patients with Parkinson's disease.

    PubMed

    Millar Vernetti, Patricio; Perez Lloret, Santiago; Rossi, Malco; Cerquetti, Daniel; Merello, Marcelo

    2012-05-01

    BAKCKGROUND: Olfactory dysfunction is present in up to 90% of Parkinson's disease (PD) patients. It is usually evaluated by means of objective standardized tests; however no self-administered scales have been developed for olfactory dysfunction bedside assessment. We present validation of a new scale to assess this symptom in PD patients. Seventy-five PD patients and 25 control subjects were evaluated using a Hyposmia Rating Scale developed in-house, combined with the extended Sniffin' Sticks test. Total score of the 6-item Hyposmia Rating Scale showed significant correlation with threshold, discrimination, identification and total Sniffin' Sticks test scores (r = 0.53; r = 0.60; r = 0.57; r = 0.65 respectively, p < 0.001 for all values). Area under the curve of the receiver operating curve for the ability of Hyposmia Rating Scale to discriminate patients with Sniffin' Sticks test total scores below or above the cut-off point was 80 ± 6% (p < 0.001). Considering Sniffin' Sticks test as the gold standard method for olfactory dysfunction detection, an affirmative response to a single screening question about smelling ability problems showed 35% sensitivity (95%CI = 23-47%) and 100% specificity. The best cut-off point for Hyposmia Rating Scale was 22.5 with a sensitivity of 70% (60-81%) and a specificity of 85% (65-100%). The Hyposmia Rating Scale here presented may offer a simple, cost-effective, time-saving and reliable approach to evaluate olfactory dysfunction in PD patients. Copyright © 2011. Published by Elsevier Ltd.

  15. Sumatran orangutans differ in their cultural knowledge but not in their cognitive abilities.

    PubMed

    Gruber, Thibaud; Singleton, Ian; van Schaik, Carel

    2012-12-04

    Animal cultures are controversial because the method used to isolate culture in animals aims at excluding genetic and environmental influences rather than demonstrating social learning. Here, we analyzed these factors in parallel in captivity to determine their influences on tool use. We exposed Sumatran orangutan (Pongo abelii) orphans from tool-using and non-tool-using regions (western swamps and eastern Langkat, respectively) that differed in both genetic and cultural backgrounds to a raking task and a honey-dipping task to assess their understanding of stick use. Orangutans from both regions were equally successful in raking; however, swamp orangutans were more successful than Langkat orangutans in honey dipping, where previously acquired knowledge was required. A larger analysis suggested that the Alas River could constitute a geographical barrier to the spread of this cultural trait. Finally, honey-dipping individuals were on average less than 4 years old, but this behavior is not observed in the wild before 6 years of age. Our results suggest first that genetic differences between wild Sumatran populations cannot explain their differences in stick use; however, their performances in honey dipping support a cultural differentiation in stick knowledge. Second, the results suggest that the honey-dippers were too young when arriving at the quarantine center to have possibly mastered the behavior in the wild individually, suggesting that they arrived with preestablished mental representations of stick use or, simply put, "cultural ideas." Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Grain scale observations of stick-slip dynamics in fluid saturated granular fault gouge

    NASA Astrophysics Data System (ADS)

    Johnson, P. A.; Dorostkar, O.; Guyer, R. A.; Marone, C.; Carmeliet, J.

    2017-12-01

    We are studying granular mechanics during slip. In the present work, we conduct coupled computational fluid dynamics (CFD) and discrete element method (DEM) simulations to study grain scale characteristics of slip instabilities in fluid saturated granular fault gouge. The granular sample is confined with constant normal load (10 MPa), and sheared with constant velocity (0.6 mm/s). This loading configuration is chosen to promote stick-slip dynamics, based on a phase-space study. Fluid is introduced in the beginning of stick phase and characteristics of slip events i.e. macroscopic friction coefficient, kinetic energy and layer thickness are monitored. At the grain scale, we monitor particle coordination number, fluid-particle interaction forces as well as particle and fluid kinetic energy. Our observations show that presence of fluids in a drained granular fault gouge stabilizes the layer in the stick phase and increases the recurrence time. In saturated model, we observe that average particle coordination number reaches higher values compared to dry granular gouge. Upon slip, we observe that a larger portion of the granular sample is mobilized in saturated gouge compared to dry system. We also observe that regions with high particle kinetic energy are correlated with zones of high fluid motion. Our observations highlight that spatiotemporal profile of fluid dynamic pressure affects the characteristics of slip instabilities, increasing macroscopic friction coefficient drop, kinetic energy release and granular layer compaction. We show that numerical simulations help characterize the micromechanics of fault mechanics.

  17. Programs for analysis and resizing of complex structures. [computerized minimum weight design

    NASA Technical Reports Server (NTRS)

    Haftka, R. T.; Prasad, B.

    1978-01-01

    The paper describes the PARS (Programs for Analysis and Resizing of Structures) system. PARS is a user oriented system of programs for the minimum weight design of structures modeled by finite elements and subject to stress, displacement, flutter and thermal constraints. The system is built around SPAR - an efficient and modular general purpose finite element program, and consists of a series of processors that communicate through the use of a data base. An efficient optimizer based on the Sequence of Unconstrained Minimization Technique (SUMT) with an extended interior penalty function and Newton's method is used. Several problems are presented for demonstration of the system capabilities.

  18. Achieving spectrum conservation for the minimum-span and minimum-order frequency assignment problems

    NASA Technical Reports Server (NTRS)

    Heyward, Ann O.

    1992-01-01

    Effective and efficient solutions of frequency assignment problems assumes increasing importance as the radiofrequency spectrum experiences ever increasing utilization by diverse communications services, requiring that the most efficient use of this resource be achieved. The research presented explores a general approach to the frequency assignment problem, in which such problems are categorized by the appropriate spectrum conserving objective function, and are each treated as an N-job, M-machine scheduling problem appropriate for the objective. Results obtained and presented illustrate that such an approach presents an effective means of achieving spectrum conserving frequency assignments for communications systems in a variety of environments.

  19. Spectral analysis of the stick-slip phenomenon in "oral" tribological texture evaluation.

    PubMed

    Sanahuja, Solange; Upadhyay, Rutuja; Briesen, Heiko; Chen, Jianshe

    2017-08-01

    "Oral" tribology has become a new paradigm in food texture studies to understand complex texture attributes, such as creaminess, oiliness, and astringency, which could not be successfully characterized by traditional texture analysis nor by rheology. Stick-slip effects resulting from intermittent sliding motion during kinetic friction of oral mucosa could constitute an additional determining factor of sensory perception where traditional friction coefficient values and their Stribeck regimes fail in predicting different lubricant (food bolus and saliva) behaviors. It was hypothesized that the observed jagged behavior of most sliding force curves are due to stick-slip effects and depend on test velocity, normal load, surface roughness as well as lubricant type. Therefore, different measurement set-ups were investigated: sliding velocities from 0.01 to 40 mm/s, loads of 0.5 and 2.5 N as well as a smooth and a textured silicone contact surface. Moreover, dry contact measurements were compared to model food systems, such as water, oil, and oil-in-water emulsions. Spectral analysis permitted to extract the distribution of stick-slip magnitudes for specific wave numbers, characterizing the occurrence of jagged force peaks per unit sliding distance, similar to frequencies per unit time. The spectral features were affected by all the above mentioned tested factors. Stick-slip created vibration frequencies in the range of those detected by oral mechanoreceptors (0.3-400 Hz). The study thus provides a new insight into the use of tribology in food psychophysics. Dynamic spectral analysis has been applied for the first time to the force-displacement curves in "oral" tribology. Analyzing the stick-slip phenomenon in the dynamic friction provides new information that is generally overlooked or confused with machine noise and which may help to understand friction-related sensory attributes. This approach allows us to differentiate samples that have similar friction coefficient, but are perceived differently in the mouth. The next step of our research will be to combine spectral attributes, such as the magnitudes of specific wave number bands and possibly their evolution during sliding, together with friction coefficient and viscosity values of foods with sensory results. The highest potential lies in predicting smoothness in opposition to roughness of a surface, such as a rough tongue when eating astringent or dry foods, or of particles when eating grainy foods. The effects of food ingredients at the nano to macroscales can then be used to optimize a specific lubrication behavior. © 2017 Wiley Periodicals, Inc.

  20. Hydrogen Recombination and Dimer Formation on Graphite from Ab Initio Molecular Dynamics Simulations.

    PubMed

    Casolo, S; Tantardini, G F; Martinazzo, R

    2016-07-14

    We studied Eley-Rideal molecular hydrogen formation on graphite using ab initio molecular dynamics, in the energy range relevant for the chemistry of the interstellar medium and for terrestrial experiments employing cold plasma (0.02-1 eV). We found substantial projectile steering effects that prevent dimer formation at low energies, thereby ruling out any catalytic synthetic pathways that form hydrogen molecules. Ortho and para dimers do form efficiently thanks to preferential sticking, but only at energies that are too high to be relevant for the chemistry of the interstellar medium. Computed reaction cross sections and ro-vibrational product populations are in good agreement with available experimental data and capable of generating adsorbate configurations similar to those observed with scanning tunneling microscopy techniques.

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