Sample records for load transfer method

  1. Method to Eliminate Flux Linkage DC Component in Load Transformer for Static Transfer Switch

    PubMed Central

    2014-01-01

    Many industrial and commercial sensitive loads are subject to the voltage sags and interruptions. The static transfer switch (STS) based on the thyristors is applied to improve the power quality and reliability. However, the transfer will result in severe inrush current in the load transformer, because of the DC component in the magnetic flux generated in the transfer process. The inrush current which is always 2~30 p.u. can cause the disoperation of relay protective devices and bring potential damage to the transformer. The way to eliminate the DC component is to transfer the related phases when the residual flux linkage of the load transformer and the prospective flux linkage of the alternate source are equal. This paper analyzes how the flux linkage of each winding in the load transformer changes in the transfer process. Based on the residual flux linkage when the preferred source is completely disconnected, the method to calculate the proper time point to close each phase of the alternate source is developed. Simulation and laboratory experiments results are presented to show the effectiveness of the transfer method. PMID:25133255

  2. Method to eliminate flux linkage DC component in load transformer for static transfer switch.

    PubMed

    He, Yu; Mao, Chengxiong; Lu, Jiming; Wang, Dan; Tian, Bing

    2014-01-01

    Many industrial and commercial sensitive loads are subject to the voltage sags and interruptions. The static transfer switch (STS) based on the thyristors is applied to improve the power quality and reliability. However, the transfer will result in severe inrush current in the load transformer, because of the DC component in the magnetic flux generated in the transfer process. The inrush current which is always 2 ~ 30 p.u. can cause the disoperation of relay protective devices and bring potential damage to the transformer. The way to eliminate the DC component is to transfer the related phases when the residual flux linkage of the load transformer and the prospective flux linkage of the alternate source are equal. This paper analyzes how the flux linkage of each winding in the load transformer changes in the transfer process. Based on the residual flux linkage when the preferred source is completely disconnected, the method to calculate the proper time point to close each phase of the alternate source is developed. Simulation and laboratory experiments results are presented to show the effectiveness of the transfer method.

  3. Method and apparatus for transfer function simulator for testing complex systems

    NASA Technical Reports Server (NTRS)

    Kavaya, M. J. (Inventor)

    1985-01-01

    A method and apparatus for testing the operation of a complex stabilization circuit in a closed loop system is presented. The method is comprised of a programmed analog or digital computing system for implementing the transfer function of a load thereby providing a predictable load. The digital computing system employs a table stored in a microprocessor in which precomputed values of the load transfer function are stored for values of input signal from the stabilization circuit over the range of interest. This technique may be used not only for isolating faults in the stabilization circuit, but also for analyzing a fault in a faulty load by so varying parameters of the computing system as to simulate operation of the actual load with the fault.

  4. Compensated Box-Jenkins transfer function for short term load forecast

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

    Breipohl, A.; Yu, Z.; Lee, F.N.

    In the past years, the Box-Jenkins ARIMA method and the Box-Jenkins transfer function method (BJTF) have been among the most commonly used methods for short term electrical load forecasting. But when there exists a sudden change in the temperature, both methods tend to exhibit larger errors in the forecast. This paper demonstrates that the load forecasting errors resulting from either the BJ ARIMA model or the BJTF model are not simply white noise, but rather well-patterned noise, and the patterns in the noise can be used to improve the forecasts. Thus a compensated Box-Jenkins transfer method (CBJTF) is proposed tomore » improve the accuracy of the load prediction. Some case studies have been made which result in about a 14-33% reduction of the root mean square (RMS) errors of the forecasts, depending on the compensation time period as well as the compensation method used.« less

  5. The effect of fatigue cracks on fastener flexibility, load distribution, and fatigue crack growth

    NASA Astrophysics Data System (ADS)

    Whitman, Zachary Layne

    Fatigue cracks typically occur at stress risers such as geometry changes and holes. This type of failure has serious safety and economic repercussions affecting structures such as aircraft. The need to prevent catastrophic failure due to fatigue cracks and other discontinuities has led to durability and damage tolerant methodologies influencing the design of aircraft structures. Holes in a plate or sheet filled with a fastener are common fatigue critical locations in aircraft structure requiring damage tolerance analysis (DTA). Often, the fastener is transferring load which leads to a loading condition involving both far-field stresses such as tension and bending, and localized bearing at the hole. The difference between the bearing stress and the tensile field at the hole is known as load transfer. The ratio of load transfer as well as the magnitude of the stresses plays a significant part in how quickly a crack will progress to failure. Unfortunately, the determination of load transfer in a complex joint is far from trivial. Many methods exist in the open literature regarding the analysis of splices, doublers and attachment joints to determine individual fastener loads. These methods work well for static analyses but greater refinement is needed for crack growth analysis. The first fastener in a splice or joint is typically the most critical but different fastener flexibility equations will all give different results. The constraint of the fastener head and shop end, along with the type of fastener, affects the stiffness or flexibility of the fastener. This in turn will determine the load that the fastener will transfer within a given fastener pattern. However, current methods do not account for the change in flexibility at a fastener as the crack develops. It is put forth that a crack does indeed reduce the stiffness of a fastener by changing its constraint, thus lessening the load transfer. A crack growth analysis utilizing reduced load transfer will result in a slower growing crack versus an analysis that ignores the effect.

  6. Linear and nonlinear dynamic analysis of redundant load path bearingless rotor systems

    NASA Technical Reports Server (NTRS)

    Murthy, V. R.

    1985-01-01

    The bearingless rotorcraft offers reduced weight, less complexity and superior flying qualities. Almost all the current industrial structural dynamic programs of conventional rotors which consist of single load path rotor blades employ the transfer matrix method to determine natural vibration characteristics because this method is ideally suited for one dimensional chain like structures. This method is extended to multiple load path rotor blades without resorting to an equivalent single load path approximation. Unlike the conventional blades, it isk necessary to introduce the axial-degree-of-freedom into the solution process to account for the differential axial displacements in the different load paths. With the present extension, the current rotor dynamic programs can be modified with relative ease to account for the multiple load paths without resorting to the equivalent single load path modeling. The results obtained by the transfer matrix method are validated by comparing with the finite element solutions. A differential stiffness matrix due to blade rotation is derived to facilitate the finite element solutions.

  7. [Nasal submicron emulsion of Scutellariae Radix extract preparation technology research based on phase transfer of solute technology].

    PubMed

    Shi, Ya-jun; Shi, Jun-hui; Chen, Shi-bin; Yang, Ming

    2015-07-01

    Based on the demand of nasal drug delivery high drug loadings, using the unique phase transfer of solute, integrating the phospholipid complex preparation and submicron emulsion molding process of Scutellariae Radix extract, the study obtained the preparation of the high drug loadings submicron emulsion of Scutellariae Radix extract. In the study of drug solution dispersion method, the uniformity of drug dispersed as the evaluation index, the traditional mixing method, grinding, homogenate and solute phase transfer technology were investigated, and the solute phase transfer technology was adopted in the last. With the adoption of new technology, the drug loading capacity reached 1.33% (phospholipid complex was 4%). The drug loading capacity was improved significantly. The transfer of solute method and timing were studied as follows,join the oil phase when the volume of phospholipid complex anhydrous ethanol solution remaining 30%, the solute phase transfer was completed with the continued recycling of anhydrous ethanol. After drug dissolved away to oil phase, the preparation technology of colostrum was determined with the evaluation index of emulsion droplet form. The particle size of submicron emulsion, PDI and stability parameters were used as evaluation index, orthogonal methodology were adopted to optimize the submicron emulsion ingredient and main influential factors of high pressure homogenization technology. The optimized preparation technology of Scutellariae Radix extract nasal submicron emulsion is practical and stable.

  8. The influence of cognitive load on transfer with error prevention training methods: a meta-analysis.

    PubMed

    Hutchins, Shaun D; Wickens, Christopher D; Carolan, Thomas F; Cumming, John M

    2013-08-01

    The objective was to conduct research synthesis for the U.S.Army on the effectiveness of two error prevention training strategies (training wheels and scaffolding) on the transfer of training. Motivated as part of an ongoing program of research on training effectiveness, the current work presents some of the program's research into the effects on transfer of error prevention strategies during training from a cognitive load perspective. Based on cognitive load theory, two training strategies were hypothesized to reduce intrinsic load by supporting learners early in acquisition during schema development. A transfer ratio and Hedges' g were used in the two meta-analyses conducted on transfer studies employing the two training strategies. Moderators relevant to cognitive load theory and specific to the implemented strategies were examined.The transfer ratio was the ratio of treatment transfer performance to control transfer. Hedges' g was used in comparing treatment and control group standardized mean differences. Both effect sizes were analyzed with versions of sample weighted fixed effect models. Analysis of the training wheels strategy suggests a transfer benefit. The observed benefit was strongest when the training wheels were a worked example coupled with a principle-based prompt. Analysis of the scaffolding data also suggests a transfer benefit for the strategy. Both training wheels and scaffolding demonstrated positive transfer as training strategies.As error prevention techniques, both support the intrinsic load--reducing implications of cognitive load theory. The findings are applicable to the development of instructional design guidelines in professional skill-based organizations such as the military.

  9. The Effect of Fatigue Cracks on Fastener Flexibility, Load Distribution and Fatigue Crack Growth

    DTIC Science & Technology

    2012-05-01

    fastener will transfer within a given fastener pattern. iv iv However, current methods do not account for the change in flexibility at a fastener...affects the growth of the crack. Thus, as the effect of the crack starts to impact the load transfer of the joint there is a need to account for...not account for spectrum loading but typically were cycled from 1g to limit or maximum flight load and then correlated to measured usage using

  10. Dynamic load testing on the bearing capacity of prestressed tubular concrete piles in soft ground

    NASA Astrophysics Data System (ADS)

    Yu, Chuang; Liu, Songyu

    2008-11-01

    Dynamic load testing (DLT) is a high strain test method for assessing pile performance. The shaft capacity of a driven PTC (prestressed tubular concrete) pile in marine soft ground will vary with time after installation. The DLT method has been successfully transferred to the testing of prestressed pipe piles in marine soft clay of Lianyungang area in China. DLT is investigated to determine the ultimate bearing capacity of single pile at different period after pile installation. The ultimate bearing capacity of single pile was founded to increase more than 70% during the inventing 3 months, which demonstrate the time effect of rigid pile bearing capacity in marine soft ground. Furthermore, the skin friction and axial force along the pile shaft are presented as well, which present the load transfer mechanism of pipe pile in soft clay. It shows the economy and efficiency of DLT method compared to static load testing method.

  11. Heat exchanger device and method for heat removal or transfer

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

    Koplow, Jeffrey P

    2015-03-24

    Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a heat conducting structure, across a narrow air gap, to a rotating heat transfer structure immersed in a surrounding medium such as air.

  12. Heat exchanger device and method for heat removal or transfer

    DOEpatents

    Koplow, Jeffrey P [San Ramon, CA

    2012-07-24

    Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a heat conducting structure, across a narrow air gap, to a rotating heat transfer structure immersed in a surrounding medium such as air.

  13. Heat exchanger device and method for heat removal or transfer

    DOEpatents

    Koplow, Jeffrey P

    2013-12-10

    Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a heat conducting structure, across a narrow air gap, to a rotating heat transfer structure immersed in a surrounding medium such as air.

  14. Heat exchanger device and method for heat removal or transfer

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

    Koplow, Jeffrey P.

    2015-12-08

    Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a heat conducting structure, across a narrow air gap, to a rotating heat transfer structure immersed in a surrounding medium such as air.

  15. A temperature match based optimization method for daily load prediction considering DLC effect

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

    Yu, Z.

    This paper presents a unique optimization method for short term load forecasting. The new method is based on the optimal template temperature match between the future and past temperatures. The optimal error reduction technique is a new concept introduced in this paper. Two case studies show that for hourly load forecasting, this method can yield results as good as the rather complicated Box-Jenkins Transfer Function method, and better than the Box-Jenkins method; for peak load prediction, this method is comparable in accuracy to the neural network method with back propagation, and can produce more accurate results than the multi-linear regressionmore » method. The DLC effect on system load is also considered in this method.« less

  16. Lower extremity kinematics that correlate with success in lateral load transfers over a low friction surface.

    PubMed

    Catena, Robert D; Xu, Xu

    2015-01-01

    We previously studied balance during lateral load transfers, but were left without explanation of why some individuals were successful in novel low friction conditions and others were not. Here, we retrospectively examined lower extremity kinematics between successful (SL) and unsuccessful (UL) groups to determine what characteristics may improve low friction performance. Success versus failure over a novel slippery surface was used to dichotomise 35 healthy working-age individuals into the two groups (SL and UL). Participants performed lateral load transfers over three sequential surface conditions: high friction, novel low friction, and practiced low friction. The UL group used a wide stance with rotation mostly at the hips during the high and novel low friction conditions. To successfully complete the practiced low friction task, they narrowed their stance and pivoted both feet and torso towards the direction of the load, similar to the SL group in all conditions. This successful kinematic method potentially results in reduced muscle demand throughout the task. Practitioner Summary: The reason for this paper is to retrospectively examine the different load transfer strategies that are used in a low friction lateral load transfer. We found stance width to be the major source of success, while sagittal plane motion was altered to potentially maintain balance.

  17. A new drilling method-Earthworm-like vibration drilling.

    PubMed

    Wang, Peng; Ni, Hongjian; Wang, Ruihe

    2018-01-01

    The load transfer difficulty caused by borehole wall friction severely limits the penetration rate and extended-reach limit of complex structural wells. A new friction reduction technology termed "earthworm-like drilling" is proposed in this paper to improve the load transfer of complex structural wells. A mathematical model based on a "soft-string" model is developed and solved. The results show that earthworm-like drilling is more effective than single-point vibration drilling. The amplitude and frequency of the pulse pressure and the installation position of the shakers have a substantial impact on friction reduction and load transfer. An optimization model based on the projection gradient method is developed and used to optimize the position of three shakers in a horizontal well. The results verify the feasibility and advantages of earthworm-like drilling, and establish a solid theoretical foundation for its application in oil field drilling.

  18. Optimization of Doxorubicin Loading for Superabsorbent Polymer Microspheres: in vitro Analysis

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

    Liu, David M., E-mail: dave.liu@vch.ca; Kos, Sebastian; Buczkowski, Andrzej

    2012-04-15

    Purpose: This study was designed to establish the ability of super-absorbent polymer microspheres (SAP) to actively uptake doxorubicin and to establish the proof of principle of SAP's ability to phase transfer doxorubicin onto the polymer matrix and to elute into buffer with a loading method that optimizes physical handling and elution characteristics. Methods: Phase I: 50-100 {mu}m SAP subject to various prehydration methods (normal saline 10 cc, hypertonic saline 4 cc, iodinated contrast 10 cc) or left in their dry state, and combined with 50 mg of clinical grade lyophilized doxorubicin reconstituted with various methods (normal saline 10 cc andmore » 25 cc, sterile water 4 cc, iodinated contrast 5 cc) were placed in buffer and assessed based on loading, handling, and elution utilizing high-performance liquid chromatography (HPLC). Phase II: top two performing methods were subject to loading of doxorubicin (50, 75, 100 mg) in a single bolus (group A) or as a serial loading method (group B) followed by measurement of loading vs. time and elution vs. time. Results: Phase I revealed the most effective loading mechanisms and easiest handling to be dry (group A) vs. normal saline prehydrated (group B) SAP with normal saline reconstituted doxorubicin (10 mg/mL) with loading efficiencies of 83.1% and 88.4%. Phase II results revealed unstable behavior of SAP with 100 mg of doxorubicin and similar loading/elution profiles of dry and prehydrated SAP, with superior handling characteristics of group B SAP at 50 and 75 mg. Conclusions: SAP demonstrates the ability to load and bulk phase transfer doxorubicin at 50 and 75 mg with ease of handling and optimal efficiency through dry loading of SAP.« less

  19. Optimization of doxorubicin loading for superabsorbent polymer microspheres: in vitro analysis.

    PubMed

    Liu, David M; Kos, Sebastian; Buczkowski, Andrzej; Kee, Stephen; Munk, Peter L; Klass, Darren; Wasan, Ellen

    2012-04-01

    This study was designed to establish the ability of super-absorbent polymer microspheres (SAP) to actively uptake doxorubicin and to establish the proof of principle of SAP's ability to phase transfer doxorubicin onto the polymer matrix and to elute into buffer with a loading method that optimizes physical handling and elution characteristics. Phase I: 50-100 μm SAP subject to various prehydration methods (normal saline 10 cc, hypertonic saline 4 cc, iodinated contrast 10 cc) or left in their dry state, and combined with 50 mg of clinical grade lyophilized doxorubicin reconstituted with various methods (normal saline 10 cc and 25 cc, sterile water 4 cc, iodinated contrast 5 cc) were placed in buffer and assessed based on loading, handling, and elution utilizing high-performance liquid chromatography (HPLC). Phase II: top two performing methods were subject to loading of doxorubicin (50, 75, 100 mg) in a single bolus (group A) or as a serial loading method (group B) followed by measurement of loading vs. time and elution vs. time. Phase I revealed the most effective loading mechanisms and easiest handling to be dry (group A) vs. normal saline prehydrated (group B) SAP with normal saline reconstituted doxorubicin (10 mg/mL) with loading efficiencies of 83.1% and 88.4%. Phase II results revealed unstable behavior of SAP with 100 mg of doxorubicin and similar loading/elution profiles of dry and prehydrated SAP, with superior handling characteristics of group B SAP at 50 and 75 mg. SAP demonstrates the ability to load and bulk phase transfer doxorubicin at 50 and 75 mg with ease of handling and optimal efficiency through dry loading of SAP.

  20. Influence of acoustic impedance of multilayer acoustic systems on the transfer function of ultrasonic airborne transducers.

    PubMed

    Gudra, Tadeusz; Opieliński, Krzysztof J

    2002-05-01

    In different solutions of ultrasonic transducers radiating acoustic energy into the air there occurs the problem of the proper selection of the acoustic impedance of one or more matching layers. The goal of this work was a computer analysis of the influence of acoustic impedance on the transfer function of piezoceramic transducers equipped with matching layers. Cases of resonance and non-resonance matching impedance in relation to the transfer function and the energy transmission coefficient for solid state-air systems were analysed. With stable thickness of matching layers the required shape of the transfer function can be obtained through proper choice of acoustic impedance were built (e.g. maximal flat function). The proper choice of acoustic impedance requires an elaboration of precise methods of synthesis of matching systems. Using the known matching criteria (Chebyshev's, DeSilets', Souquet's), the transfer function characteristics of transducers equipped with one, two, and three matching layers as well as the optimisation methods of the energy transmission coefficient were presented. The influence of the backside load of the transducer on the shape of transfer function was also analysed. The calculation results of this function for different loads of the transducer backside without and with the different matching layers were presented. The proper load selection allows us to obtain the desired shape of the transfer function, which determines the pulse shape generated by the transducer.

  1. Checking transfer efficiency and equal loading via qualitative optical way in western blotting.

    PubMed

    Gong, Jun-Hua; Gong, Jian-Ping; Zheng, Kai-Wen

    2017-11-01

    The ability to determine that successful transfer and equal loading occur prior to using primary antibodies is important. And total protein staining is commonly used to check transfer efficiency and normalization, which play a crucial role in western blotting. Ponceau S and coomassie blue are commonly used, but there are disadvantages reported in recent years. Therefore, we are interested in finding another method, which is cheap, easy and fast. As we know, protein binding region of PVDF membrane is still hydrophilic when carbinol volatilizes, however, the non-protein binding region of PVDF membrane became hydrophobic again. And this different wettability between non-protein binding region and protein binding region of Polyvinylidene difluoride membrane may be used to check transfer efficiency and equal loading in western blotting. Based on the principle above, we describe an optical approach where an experimenter can observe that the proteins have been transferred to the membrane without any staining within minutes. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Phase change based cooling for high burst mode heat loads with temperature regulation above the phase change temperature

    DOEpatents

    The United States of America as represented by the United States Department of Energy

    2009-12-15

    An apparatus and method for transferring thermal energy from a heat load is disclosed. In particular, use of a phase change material and specific flow designs enables cooling with temperature regulation well above the fusion temperature of the phase change material for medium and high heat loads from devices operated intermittently (in burst mode). Exemplary heat loads include burst mode lasers and laser diodes, flight avionics, and high power space instruments. Thermal energy is transferred from the heat load to liquid phase change material from a phase change material reservoir. The liquid phase change material is split into two flows. Thermal energy is transferred from the first flow via a phase change material heat sink. The second flow bypasses the phase change material heat sink and joins with liquid phase change material exiting from the phase change material heat sink. The combined liquid phase change material is returned to the liquid phase change material reservoir. The ratio of bypass flow to flow into the phase change material heat sink can be varied to adjust the temperature of the liquid phase change material returned to the liquid phase change material reservoir. Varying the flowrate and temperature of the liquid phase change material presented to the heat load determines the magnitude of thermal energy transferred from the heat load.

  3. Assessing the Validity of Using Serious Game Technology to Analyze Physician Decision Making

    PubMed Central

    Mohan, Deepika; Angus, Derek C.; Ricketts, Daniel; Farris, Coreen; Fischhoff, Baruch; Rosengart, Matthew R.; Yealy, Donald M.; Barnato, Amber E.

    2014-01-01

    Background Physician non-compliance with clinical practice guidelines remains a critical barrier to high quality care. Serious games (using gaming technology for serious purposes) have emerged as a method of studying physician decision making. However, little is known about their validity. Methods We created a serious game and evaluated its construct validity. We used the decision context of trauma triage in the Emergency Department of non-trauma centers, given widely accepted guidelines that recommend the transfer of severely injured patients to trauma centers. We designed cases with the premise that the representativeness heuristic influences triage (i.e. physicians make transfer decisions based on archetypes of severely injured patients rather than guidelines). We randomized a convenience sample of emergency medicine physicians to a control or cognitive load arm, and compared performance (disposition decisions, number of orders entered, time spent per case). We hypothesized that cognitive load would increase the use of heuristics, increasing the transfer of representative cases and decreasing the transfer of non-representative cases. Findings We recruited 209 physicians, of whom 168 (79%) began and 142 (68%) completed the task. Physicians transferred 31% of severely injured patients during the game, consistent with rates of transfer for severely injured patients in practice. They entered the same average number of orders in both arms (control (C): 10.9 [SD 4.8] vs. cognitive load (CL):10.7 [SD 5.6], p = 0.74), despite spending less time per case in the control arm (C: 9.7 [SD 7.1] vs. CL: 11.7 [SD 6.7] minutes, p<0.01). Physicians were equally likely to transfer representative cases in the two arms (C: 45% vs. CL: 34%, p = 0.20), but were more likely to transfer non-representative cases in the control arm (C: 38% vs. CL: 26%, p = 0.03). Conclusions We found that physicians made decisions consistent with actual practice, that we could manipulate cognitive load, and that load increased the use of heuristics, as predicted by cognitive theory. PMID:25153149

  4. Diffusive transfer to membranes as an effective interface between gel electrophoresis and mass spectrometry

    NASA Astrophysics Data System (ADS)

    Ogorzalek Loo, Rachel R.; Mitchell, Charles; Stevenson, Tracy I.; Loo, Joseph A.; Andrews, Philip C.

    1997-12-01

    Diffusive transfer was examined as a blotting method to transfer proteins from polyacrylamide gels to membranes for ultraviolet matrix-assisted laser desorption ionization (MALDI) mass spectrometry. The method is well-suited for transfers from isoelectric focusing (IEF) gels. Spectra have been obtained for 11 pmol of 66 kDa albumin loaded onto an IEF gel and subsequently blotted to polyethylene. Similarly, masses of intact carbonic anhydrase and hemoglobin were obtained from 14 and 20 pmol loadings. This methodology is also compatible with blotting high molecular weight proteins, as seen for 6 pmol of the 150 kDa monoclonal antibody anti-[beta]-galactosidase transferred to Goretex. Polypropylene, Teflon, Nafion and polyvinylidene difluoride (PVDF) also produced good spectra following diffusive transfer. Only analysis from PVDF required that the membrane be kept wet prior to application of matrix. Considerations in mass accuracy for analysis from large-area membranes with continuous extraction and delayed extraction were explored, as were remedies for surface charging. Vapor phase CNBr cleavage was applied to membrane-bound samples for peptide mapping.

  5. Ultrasonic power transfer from a spherical acoustic wave source to a free-free piezoelectric receiver: Modeling and experiment

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

    Shahab, S.; Gray, M.; Erturk, A., E-mail: alper.erturk@me.gatech.edu

    2015-03-14

    Contactless powering of small electronic components has lately received growing attention for wireless applications in which battery replacement or tethered charging is undesired or simply impossible, and ambient energy harvesting is not a viable solution. As an alternative to well-studied methods of contactless energy transfer, such as the inductive coupling method, the use of ultrasonic waves transmitted and received by piezoelectric devices enables larger power transmission distances, which is critical especially for deep-implanted electronic devices. Moreover, energy transfer by means of acoustic waves is well suited in situations where no electromagnetic fields are allowed. The limited literature of ultrasonic acousticmore » energy transfer is mainly centered on proof-of-concept experiments demonstrating the feasibility of this method, lacking experimentally validated modeling efforts for the resulting multiphysics problem that couples the source and receiver dynamics with domain acoustics. In this work, we present fully coupled analytical, numerical, and experimental multiphysics investigations for ultrasonic acoustic energy transfer from a spherical wave source to a piezoelectric receiver bar that operates in the 33-mode of piezoelectricity. The fluid-loaded piezoelectric receiver under free-free mechanical boundary conditions is shunted to an electrical load for quantifying the electrical power output for a given acoustic source strength of the transmitter. The analytical acoustic-piezoelectric structure interaction modeling framework is validated experimentally, and the effects of system parameters are reported along with optimal electrical loading and frequency conditions of the receiver.« less

  6. 40 CFR 63.9075 - What definitions apply to this subpart?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... loading, into a tank truck, railcar, ship, or barge, of liquid HCl from a transfer (or loading) rack (as... (or loading) rack is the material that is loaded by the transfer (or loading) rack in the greatest.... Transfer (or loading) rack means the collection of loading arms and loading hoses, at a single loading rack...

  7. Efficiency Enhancement for an Inductive Wireless Power Transfer System by Optimizing the Impedance Matching Networks.

    PubMed

    Miao, Zhidong; Liu, Dake; Gong, Chen

    2017-10-01

    Inductive wireless power transfer (IWPT) is a promising power technology for implantable biomedical devices, where the power consumption is low and the efficiency is the most important consideration. In this paper, we propose an optimization method of impedance matching networks (IMN) to maximize the IWPT efficiency. The IMN at the load side is designed to achieve the optimal load, and the IMN at the source side is designed to deliver the required amount of power (no-more-no-less) from the power source to the load. The theoretical analyses and design procedure are given. An IWPT system for an implantable glaucoma therapeutic prototype is designed as an example. Compared with the efficiency of the resonant IWPT system, the efficiency of our optimized system increases with a factor of 1.73. Besides, the efficiency of our optimized IWPT system is 1.97 times higher than that of the IWPT system optimized by the traditional maximum power transfer method. All the discussions indicate that the optimization method proposed in this paper could achieve a high efficiency and long working time when the system is powered by a battery.

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

    Jacobsen, A. J.

    In a method of the type where petrol is recovered from a mixture of petrol vapor and air by absorption of the petrol in a cooled petroleum distillate, a petroleum distillate having a boiling point range higher than that of the petrol is used, and this petroleum distillate is in sequence cooled by heat exchange with a cold reservoir, brought into direct contact with the petrol/air mixture to absorb petrol, transferred to a buffer tank and transferred from the buffer tank to a stripping means which may be a distillation column. By combining cooling condensation and absorption of the petrolmore » vapor and controlling the amount of cooled petroleum distillate brought into contact with the petrol/air mixture so that the petrol concentration in the petroleum distillate transferred to the buffer tank is substantially constant, an unprecedented optimum control of the petrol absorbing process can be obtained both in peak load and in average load operations. A system for carrying out the method is advantageous in that only the absorption means need be dimensioned for peak load operation, while the other components, such as the distillation column or a heat exchanger with associated conduits can be dimensioned for average loads, a buffer tank being provided to temporarily receive the petroleum distillate which owing to the above-mentioned control has a substantially constant, maximum petrol concentration so that the system can cope with peak loads with a surprisingly small buffer tank.« less

  9. Superconducting coil and method of stress management in a superconducting coil

    DOEpatents

    McIntyre, Peter M.; Shen, Weijun; Diaczenko, Nick; Gross, Dan A.

    1999-01-01

    A superconducting coil (12) having a plurality of superconducting layers (18) is provided. Each superconducting layer (18) may have at least one superconducting element (20) which produces an operational load. An outer support structure (24) may be disposed outwardly from the plurality of layers (18). A load transfer system (22) may be coupled between at least one of the superconducting elements (20) and the outer support structure (24). The load transfer system (22) may include a support matrix structure (30) operable to transfer the operational load from the superconducting element (20) directly to the outer support structure (24). A shear release layer (40) may be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a shear stress between the superconducting element (20) and the support matrix structure (30). A compliant layer (42) may also be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a compressive stress on the superconducting element (20).

  10. Collaborative use of virtual patients after a lecture enhances learning with minimal investment of cognitive load.

    PubMed

    Marei, Hesham F; Donkers, Jeroen; Al-Eraky, Mohamed M; Van Merrienboer, Jeroen J G

    2018-05-25

    The use of virtual patients (VPs), due to their high complexity and/or inappropriate sequencing with other instructional methods, might cause a high cognitive load, which hampers learning. To investigate the efficiency of instructional methods that involved three different applications of VPs combined with lectures. From two consecutive batches, 171 out of 183 students have participated in lecture and VPs sessions. One group received a lecture session followed by a collaborative VPs learning activity (collaborative deductive). The other two groups received a lecture session and an independent VP learning activity, which either followed the lecture session (independent deductive) or preceded it (independent inductive). All groups were administrated written knowledge acquisition and retention tests as well as transfer tests using two new VPs. All participants completed a cognitive load questionnaire, which measured intrinsic, extraneous and germane load. Mixed effect analysis of cognitive load and efficiency using the R statistical program was performed. The highest intrinsic and extraneous load was found in the independent inductive group, while the lowest intrinsic and extraneous load was seen in the collaborative deductive group. Furthermore, comparisons showed a significantly higher efficiency, that is, higher performance in combination with lower cognitive load, for the collaborative deductive group than for the other two groups. Collaborative use of VPs after a lecture is the most efficient instructional method, of those tested, as it leads to better learning and transfer combined with lower cognitive load, when compared with independent use of VPs, either before or after the lecture.

  11. A Technique for Facile and Precise Transfer of Mouse Embryos

    PubMed Central

    Sarvari, Ali; Naderi, Mohammad Mehdi; Sadeghi, Mohammad Reza; Akhondi, Mohammad Mehdi

    2013-01-01

    Background Successful Embryo Transfer (ET) technique is a fateful step of all efforts to achieve live births from in vitro produced embryos in assisted reproductive techniques or in knockout, transgenic or cloned animal projects. Small reproductive tract of mice and limitation of current techniques may not well satisfy the requirements for mass production of genetically modified mice. Genetic abnormalities of embryos, receptivity and uterine contractions, expulsion of embryos, blood, mucus or bacterial contamination on the transfer pipette tip, technical problems and even animal strain may affect embryo transfer outcome. Methods In this study, two techniques of embryo transfer in mice were compared. In conventional technique the oviduct wall was punctured with a 30-gauge needle and the loaded Pasteur pipette with embryos and medium was inserted into the hole. In new technique, embryos that were loaded in modified micropipette with minimal medium were transferred directly to the oviduct by manual piston micro-pump easily. Embryo viability was evaluated considering the percentage of live healthy newborns. Results Results of the two techniques were compared by t-test within the NPAR1WAY procedure of SAS software (ver. 9.2). The average live birth rates in the novel methods was significantly higher (42.4%) than the conventional method (21.7%, p<0.05). Conclusion In conclusion, using new embryo transfer technique improved birth rate by preventing embryos expulsion from the oviduct, saving time and easy transfer of embryos with minimum volume of medium. PMID:23626878

  12. Composite load spectra for select space propulsion structural components

    NASA Technical Reports Server (NTRS)

    Newell, J. F.; Kurth, R. E.; Ho, H.

    1991-01-01

    The objective of this program is to develop generic load models with multiple levels of progressive sophistication to simulate the composite (combined) load spectra that are induced in space propulsion system components, representative of Space Shuttle Main Engines (SSME), such as transfer ducts, turbine blades, and liquid oxygen posts and system ducting. The first approach will consist of using state of the art probabilistic methods to describe the individual loading conditions and combinations of these loading conditions to synthesize the composite load spectra simulation. The second approach will consist of developing coupled models for composite load spectra simulation which combine the deterministic models for composite load dynamic, acoustic, high pressure, and high rotational speed, etc., load simulation using statistically varying coefficients. These coefficients will then be determined using advanced probabilistic simulation methods with and without strategically selected experimental data.

  13. Test method research on weakening interface strength of steel - concrete under cyclic loading

    NASA Astrophysics Data System (ADS)

    Liu, Ming-wei; Zhang, Fang-hua; Su, Guang-quan

    2018-02-01

    The mechanical properties of steel - concrete interface under cyclic loading are the key factors affecting the rule of horizontal load transfer, the calculation of bearing capacity and cumulative horizontal deformation. Cyclic shear test is an effective method to study the strength reduction of steel - concrete interface. A test system composed of large repeated direct shear test instrument, hydraulic servo system, data acquisition system, test control software system and so on is independently designed, and a set of test method, including the specimen preparation, the instrument preparation, the loading method and so on, is put forward. By listing a set of test results, the validity of the test method is verified. The test system and the test method based on it provide a reference for the experimental study on mechanical properties of steel - concrete interface.

  14. Total Transfer Capability Assessment Incorporating Corrective Controls for Transient Stability using TSCOPF

    NASA Astrophysics Data System (ADS)

    Hakim, Lukmanul; Kubokawa, Junji; Yorino, Naoto; Zoka, Yoshifumi; Sasaki, Yutaka

    Advancements have been made towards inclusion of both static and dynamic security into transfer capability calculation. However, to the authors' knowledge, work on considering corrective controls into the calculation has not been reported yet. Therefore, we propose a Total Transfer Capability (TTC) assessment considering transient stability corrective controls. The method is based on the Newton interior point method for nonlinear programming and transfer capability is approached as a maximization of power transfer with both static and transient stability constraints are incorporated into our Transient Stability Constrained Optimal Power Flow (TSCOPF) formulation. An interconnected power system is simulated to be subjected to a severe unbalanced 3-phase 4-line to ground fault and following the fault, generator and load are shed in a pre-defined sequence to mimic actual corrective controls. In a deregulated electricity market, both generator companies and large load customers are encouraged to actively participate in maintaining power system stability as corrective controls upon agreement of compensation for being shed following a disturbance. Implementation of this proposal on the actual power system operation should be carried out through combining it with the existing transient stabilization controller system. Utilization of these corrective controls results in increasing TTC as suggested in our numerical simulation. As Lagrange multipliers can also describe sensitivity of both inequality and equality constraints to the objective function, then selection of which generator or load to be shed can be carried out on the basis of values of Lagrange multipliers of its respective generator's rotor angle stability and active power balance equation. Hence, the proposal in this paper can be utilized by system operator to assess the maximum TTC for specific loads and network conditions.

  15. A new drilling method—Earthworm-like vibration drilling

    PubMed Central

    Wang, Peng; Wang, Ruihe

    2018-01-01

    The load transfer difficulty caused by borehole wall friction severely limits the penetration rate and extended-reach limit of complex structural wells. A new friction reduction technology termed “earthworm-like drilling” is proposed in this paper to improve the load transfer of complex structural wells. A mathematical model based on a “soft-string” model is developed and solved. The results show that earthworm-like drilling is more effective than single-point vibration drilling. The amplitude and frequency of the pulse pressure and the installation position of the shakers have a substantial impact on friction reduction and load transfer. An optimization model based on the projection gradient method is developed and used to optimize the position of three shakers in a horizontal well. The results verify the feasibility and advantages of earthworm-like drilling, and establish a solid theoretical foundation for its application in oil field drilling. PMID:29641615

  16. Assessing the validity of using serious game technology to analyze physician decision making.

    PubMed

    Mohan, Deepika; Angus, Derek C; Ricketts, Daniel; Farris, Coreen; Fischhoff, Baruch; Rosengart, Matthew R; Yealy, Donald M; Barnato, Amber E

    2014-01-01

    Physician non-compliance with clinical practice guidelines remains a critical barrier to high quality care. Serious games (using gaming technology for serious purposes) have emerged as a method of studying physician decision making. However, little is known about their validity. We created a serious game and evaluated its construct validity. We used the decision context of trauma triage in the Emergency Department of non-trauma centers, given widely accepted guidelines that recommend the transfer of severely injured patients to trauma centers. We designed cases with the premise that the representativeness heuristic influences triage (i.e. physicians make transfer decisions based on archetypes of severely injured patients rather than guidelines). We randomized a convenience sample of emergency medicine physicians to a control or cognitive load arm, and compared performance (disposition decisions, number of orders entered, time spent per case). We hypothesized that cognitive load would increase the use of heuristics, increasing the transfer of representative cases and decreasing the transfer of non-representative cases. We recruited 209 physicians, of whom 168 (79%) began and 142 (68%) completed the task. Physicians transferred 31% of severely injured patients during the game, consistent with rates of transfer for severely injured patients in practice. They entered the same average number of orders in both arms (control (C): 10.9 [SD 4.8] vs. cognitive load (CL):10.7 [SD 5.6], p = 0.74), despite spending less time per case in the control arm (C: 9.7 [SD 7.1] vs. CL: 11.7 [SD 6.7] minutes, p<0.01). Physicians were equally likely to transfer representative cases in the two arms (C: 45% vs. CL: 34%, p = 0.20), but were more likely to transfer non-representative cases in the control arm (C: 38% vs. CL: 26%, p = 0.03). We found that physicians made decisions consistent with actual practice, that we could manipulate cognitive load, and that load increased the use of heuristics, as predicted by cognitive theory.

  17. Resident Load Influence Analysis Method for Price Based on Non-intrusive Load Monitoring and Decomposition Data

    NASA Astrophysics Data System (ADS)

    Jiang, Wenqian; Zeng, Bo; Yang, Zhou; Li, Gang

    2018-01-01

    In the non-invasive load monitoring mode, the load decomposition can reflect the running state of each load, which will help the user reduce unnecessary energy costs. With the demand side management measures of time of using price, a resident load influence analysis method for time of using price (TOU) based on non-intrusive load monitoring data are proposed in the paper. Relying on the current signal of the resident load classification, the user equipment type, and different time series of self-elasticity and cross-elasticity of the situation could be obtained. Through the actual household load data test with the impact of TOU, part of the equipment will be transferred to the working hours, and users in the peak price of electricity has been reduced, and in the electricity at the time of the increase Electrical equipment, with a certain regularity.

  18. Improved memory loading techniques for the TSRV display system

    NASA Technical Reports Server (NTRS)

    Easley, W. C.; Lynn, W. A.; Mcluer, D. G.

    1986-01-01

    A recent upgrade of the TSRV research flight system at NASA Langley Research Center retained the original monochrome display system. However, the display memory loading equipment was replaced requiring design and development of new methods of performing this task. This paper describes the new techniques developed to load memory in the display system. An outdated paper tape method for loading the BOOTSTRAP control program was replaced by EPROM storage of the characters contained on the tape. Rather than move a tape past an optical reader, a counter was implemented which steps sequentially through EPROM addresses and presents the same data to the loader circuitry. A cumbersome cassette tape method for loading the applications software was replaced with a floppy disk method using a microprocessor terminal installed as part of the upgrade. The cassette memory image was transferred to disk and a specific software loader was written for the terminal which duplicates the function of the cassette loader.

  19. Echogenic Catheters and Embryo Transfer Standardization.

    PubMed

    Urbina, Maria Teresa; Benjamin, Isaac; Medina, Randolfo; Lerner, Jorge

    2015-05-01

    1.To describe the standardization process and protocols of the ET method at our center. 2.To compare the performance of non-echogenic catheters with echogenic catheters during ultrasound-guided ET. Retrospective analysis of 2630 ET performed at UNIFERTES during 1997-2014, to describe standardization process and to compare the percentage of difficult ET between echogenic and non-echogenic catheters. We tested 17 non-echogenic and three echogenic catheters. Many variables were associated with the ease of ET: informed patients, waiting time for the procedure, speculum use, clinical touch, uterine contractions, cervical mucus removal, presence of blood before or after the procedure, full bladder, ultrasound guidance, uterocervical angle, mock transfer, catheter type (soft or hard, echogenic or non-echogenic, with stylet or not), catheter loading technique, duration of embryo loading (time interval since the embryos were removed from the incubator for loading until the catheter is passed to the physician), transfer procedure (time interval from the catheter was handed to the physician until the embryos were discharged in the uterus), catheter tip placement, retained embryos, bed rest after ET, operator´s proficiency. The diversity of catheters used and the percentage of difficult transfers decrease as the use of echogenic catheters increases. This process is necessary to minimize variation, ensure high quality, safe and evidence-based practice, and improve outcomes. To standardize the ET method allowed a quicker and easier transfer. The use of echogenic catheters simplified ET procedures guided by abdominal ultrasound.

  20. The influence of direct compression powder blend transfer method from the container to the tablet press on product critical quality attributes: a case study.

    PubMed

    Teżyk, Michał; Jakubowska, Emilia; Milczewska, Kasylda; Milanowski, Bartłomiej; Voelkel, Adam; Lulek, Janina

    2017-06-01

    The aim of this article is to compare the gravitational powder blend loading method to the tablet press and manual loading in terms of their influence on tablets' critical quality attributes (CQA). The results of the study can be of practical relevance to the pharmaceutical industry in the area of direct compression of low-dose formulations, which could be prone to content uniformity (CU) issues. In the preliminary study, particle size distribution (PSD) and surface energy of raw materials were determined using laser diffraction method and inverse gas chromatography, respectively. For trials purpose, a formulation containing two pharmaceutical ingredients (APIs) was used. Tablet samples were collected during the compression progress to analyze their CQAs, namely assay and CU. Results obtained during trials indicate that tested direct compression powder blend is sensitive to applied powder handling method. Mild increase in both APIs content was observed during manual scooping. Gravitational approach (based on discharge into the drum) resulted in a decrease in CU, which is connected to a more pronounced assay increase at the end of tableting than in the case of manual loading. The correct design of blend transfer over single unit processes is an important issue and should be investigated during the development phase since it may influence the final product CQAs. The manual scooping method, although simplistic, can be a temporary solution to improve the results of API's content and uniformity when compared to industrial gravitational transfer.

  1. Method of controlling switching of a multiphase inductor-converter bridge

    DOEpatents

    Kustom, Robert L.; Fuja, Raymond E.

    1981-01-01

    In an inductor-convertor circuit for transferring electrical energy between a storage coil and a load coil using a storage thyristor bridge, a load thyristor bridge, and a set of commutating capacitors, operation is improved by a method of changing the rate of delivery of energy in a given direction. The change in rate corresponds to a predetermined change in phase angle between the load bridge and the storage bridge and comprises changing the phase of the bridge by two steps, each equal to half the predetermined change and occurring 180.degree. apart. The method assures commutation and minimizes imbalances that lead otherwise to overvoltages.

  2. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... torque measurement for each range used by the following method: (1) Warm up the dynamometer following the... transfer standard may be used to verify the torque measurement system. (1) The master load-cell and read... master load-cell for each in-use range used. (5) The in-use torque measurement must be within 2 percent...

  3. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... torque measurement for each range used by the following method: (1) Warm up the dynamometer following the... transfer standard may be used to verify the torque measurement system. (1) The master load-cell and read... master load-cell for each in-use range used. (5) The in-use torque measurement must be within 2 percent...

  4. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... torque measurement for each range used by the following method: (1) Warm up the dynamometer following the... transfer standard may be used to verify the torque measurement system. (1) The master load-cell and read... master load-cell for each in-use range used. (5) The in-use torque measurement must be within 2 percent...

  5. Load transfer of nanocomposite film on aluminum substrate.

    PubMed

    Her, Shiuh-Chuan; Chien, Pao-Chu

    2018-01-01

    Nanocomposite films have attracted much attention in recent years. Depending on the composition of the film and fabrication method, a large range of applications has been employed for nanocomposite films. In this study, nanocomposite films reinforced with multi-walled carbon nanotubes (MWCNTs) were deposited on the aluminum substrate through hot press processing. A shear lag model and Euler beam theory were employed to evaluate the stress distribution and load carrying capability of the nanocomposite film subjected to tensile load and bending moment. The influence of MWCNT on the Young's modulus and load carrying capability of the nanocomposite film was investigated through a parametric study. The theoretical predictions were verified by comparison with experimental tests. A close agreement with difference less than 6% was achieved between the theoretical prediction and experimental measurements. The Young's modulus and load transfer of the nanocomposite film reinforced with MWCNTs increases with the increase of the MWCNT loading. Compared to the neat epoxy film, nanocomposite film with 1 wt % of MWCNT exhibits an increase of 20% in both the Young's modulus and load carrying capability.

  6. 33 CFR 127.1102 - Transfer hoses and loading arms.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Transfer hoses and loading arms... Transfer hoses and loading arms. (a) Each hose within the marine transfer area for LHG used for the... transferred, in both the liquid and vapor state (if wire braid is used for reinforcement, the wire must be of...

  7. 33 CFR 127.1102 - Transfer hoses and loading arms.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Transfer hoses and loading arms... Transfer hoses and loading arms. (a) Each hose within the marine transfer area for LHG used for the... transferred, in both the liquid and vapor state (if wire braid is used for reinforcement, the wire must be of...

  8. 33 CFR 127.1102 - Transfer hoses and loading arms.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Transfer hoses and loading arms... Transfer hoses and loading arms. (a) Each hose within the marine transfer area for LHG used for the... transferred, in both the liquid and vapor state (if wire braid is used for reinforcement, the wire must be of...

  9. Method for Detecting Perlite Compaction in Large Cryogenic Tanks

    NASA Technical Reports Server (NTRS)

    Youngquist, Robert

    2010-01-01

    Perlite is the most typical insulating powder used to separate the inner and outer shells of cryogenic tanks. The inner tank holds the low-temperature commodity, while the outer shell is exposed to the ambient temperature. Perlite minimizes radiative energy transfer between the two tanks. Being a powder, perlite will settle over time, leading to the danger of transferring any loads from the inner shell to the outer shell. This can cause deformation of the outer shell, leading to damaged internal fittings. The method proposed is to place strain or displacement sensors on several locations of the outer shell. Loads induced on the shell by the expanding inner shell and perlite would be monitored, providing an indication of the location and degree of compaction.

  10. Design and Control of Hydronic Radiant Cooling Systems

    NASA Astrophysics Data System (ADS)

    Feng, Jingjuan

    Improving energy efficiency in the Heating Ventilation and Air conditioning (HVAC) systems in buildings is critical to achieve the energy reduction in the building sector, which consumes 41% of all primary energy produced in the United States, and was responsible for nearly half of U.S. CO2 emissions. Based on a report by the New Building Institute (NBI), when HVAC systems are used, about half of the zero net energy (ZNE) buildings report using a radiant cooling/heating system, often in conjunction with ground source heat pumps. Radiant systems differ from air systems in the main heat transfer mechanism used to remove heat from a space, and in their control characteristics when responding to changes in control signals and room thermal conditions. This dissertation investigates three related design and control topics: cooling load calculations, cooling capacity estimation, and control for the heavyweight radiant systems. These three issues are fundamental to the development of accurate design/modeling tools, relevant performance testing methods, and ultimately the realization of the potential energy benefits of radiant systems. Cooling load calculations are a crucial step in designing any HVAC system. In the current standards, cooling load is defined and calculated independent of HVAC system type. In this dissertation, I present research evidence that sensible zone cooling loads for radiant systems are different from cooling loads for traditional air systems. Energy simulations, in EnergyPlus, and laboratory experiments were conducted to investigate the heat transfer dynamics in spaces conditioned by radiant and air systems. The results show that the magnitude of the cooling load difference between the two systems ranges from 7-85%, and radiant systems remove heat faster than air systems. For the experimental tested conditions, 75-82% of total heat gain was removed by radiant system during the period when the heater (simulating the heat gain) was on, while for air system, 61-63% were removed. From a heat transfer perspective, the differences are mainly because the chilled surfaces directly remove part of the radiant heat gains from a zone, thereby bypassing the time-delay effect caused by the interaction of radiant heat gain with non-active thermal mass in air systems. The major conclusions based on these findings are: 1) there are important limitations in the definition of cooling load for a mixing air system described in Chapter 18 of ASHRAE Handbook of Fundamentals when applied to radiant systems; 2) due to the obvious mismatch between how radiant heat transfer is handled in traditional cooling load calculation methods compared to its central role in radiant cooling systems, this dissertation provides improvements for the current cooling load calculation method based on the Heat Balance procedure. The Radiant Time Series method is not appropriate for radiant system applications. The findings also directly apply to the selection of space heat transfer modeling algorithms that are part of all energy modeling software. Cooling capacity estimation is another critical step in a design project. The above mentioned findings and a review of the existing methods indicates that current radiant system cooling capacity estimation methods fail to take into account incident shortwave radiation generated by solar and lighting in the calculation process. This causes a significant underestimation (up to 150% for some instances) of floor cooling capacity when solar load is dominant. Building performance simulations were conducted to verify this hypothesis and quantify the impacts of solar for different design scenarios. A new simplified method was proposed to improve the predictability of the method described in ISO 11855 when solar radiation is present. The dissertation also compares the energy and comfort benefits of the model-based predictive control (MPC) method with a fine-tuned heuristic control method when applied to a heavyweight embedded surface system. A first order dynamic model of a radiant slab system was developed for implementation in model predictive controllers. A calibrated EnergyPlus model of a typical office building in California was used as a testbed for the comparison. The results indicated that MPC is able to reduce the cooling tower energy consumption by 55% and pumping power consumption by 26%, while maintaining equivalent or even better thermal comfort conditions. In summary, the dissertation work has: (1) provided clear evidence that the fundamental heat transfer mechanisms differ between radiant and air systems. These findings have important implications for the development of accurate and reliable design and energy simulation tools; (2) developed practical design methods and guidance to aid practicing engineers who are designing radiant systems; and (3) outlined future research and design tools need to advance the state-of-knowledge and design and operating guidelines for radiant systems.

  11. Effect of dowel bar looseness on measured load transfer efficiency using FWD load

    NASA Astrophysics Data System (ADS)

    Shoukry, Samir N.; William, Gergis W.; Riad, Mourad Y.

    2001-07-01

    The effect of dowel bar looseness on the joint load transfer efficiency using Falling Weight Deflectometer is the subject of this paper. The mechanism of dynamic load transfer at transverse joints of Jointed Plain Concrete Pavement is examined using nonlinear 3D finite element analysis.

  12. [Low back load reduction using mechanical lift during transfer of patients].

    PubMed

    Tomioka, Kimiko; Sakae, Kenichiro; Yasuda, Junko

    2008-07-01

    In Japanese care-work sites, care-workers (CWs) have lacked basic health risk awareness for transferring patients. Knowledge of lifting equipment and skills for transfer of patients have not been disseminated and many CWs have suffered from work-related musculoskeletal disorders, especially low back pain (LBP). In order to find better ways of patient transfer which reduce and prevent LBP, we conducted a study of low back loads and operation time during the transfer of a simulated patient, who was totally dependent from bed to wheelchair, using a mechanical lift (Lift) and manual handling (handling). Moreover we examined the levels of skill which CWs had acquired in transfer by Lift and the effects of acquired skill on low back loads and operation time. We explored low back load using surface electromyography (EMG) of the lumbar paraspinals between L3 and L4 and the trunk inclination angle (TIA) measurement method. The subjects were 5 caregivers who performed the task of transferring a simulated patient from lying on the bed to sitting in a wheelchair using the Lift and by handling. Handling transfer was assisted by two-persons at the head and foot. A 'simulated' patient (a 70 kg healthy male; instructed to keep whole body relaxed) was used in all transfer tasks. When subjects used the Lift, we made an ergonomics checklist for reduction of low back load of caregivers. Subjects performed the task 4 times and were evaluated with the checklist. The level of acquired skill was significantly improved by the guidance of the checklist. TIA was observed to be significantly lower in Lift than in handling, but with EMG no significant differences were seen between Lift and handling. The effects of acquired skill on low back loads showed that TIA was statistically reduced at high skill as compared to low skill. However, there were no significant differences between both skills in Lift and handling by EMG. Operation time of Lift showed significant shortening of operation time with high skill as compared to low skill. Operation time of Lift was about 10 times longer than handling. Thus, we suggest that transfer by Lift is a valid way of reducing the burden on CWs low back. Additionally, this study found that for reduction of LBP risk for CWs, it will be important not only to use the Lift but also to observe proper procedure and raise CW skill levels in patient transfer.

  13. How do laboratory embryo transfer techniques affect IVF outcomes? A review of current literature.

    PubMed

    Sigalos, George; Triantafyllidou, Olga; Vlahos, Nikos

    2017-04-01

    Over the last few years, many studies have focused on embryo selection methods, whereas little attention has been given to the standardization of the procedure of embryo transfer. In this review, several parameters of the embryo transfer procedure are examined, such as the: (i) culture medium volume and loading technique; (ii) syringe and catheters used for embryo transfer; (iii) viscosity and composition of the embryo transfer medium; (iv) environment of embryo culture; (v) timing of embryo transfer; (vi) and standardization of the embryo transfer techniques. The aim of this manuscript is to review these factors and compare the existing embryo transfer techniques and highlight the need for better embryo transfer standardization.

  14. Composite Load Spectra for Select Space Propulsion Structural Components

    NASA Technical Reports Server (NTRS)

    Ho, Hing W.; Newell, James F.

    1994-01-01

    Generic load models are described with multiple levels of progressive sophistication to simulate the composite (combined) load spectra (CLS) that are induced in space propulsion system components, representative of Space Shuttle Main Engines (SSME), such as transfer ducts, turbine blades and liquid oxygen (LOX) posts. These generic (coupled) models combine the deterministic models for composite load dynamic, acoustic, high-pressure and high rotational speed, etc., load simulation using statistically varying coefficients. These coefficients are then determined using advanced probabilistic simulation methods with and without strategically selected experimental data. The entire simulation process is included in a CLS computer code. Applications of the computer code to various components in conjunction with the PSAM (Probabilistic Structural Analysis Method) to perform probabilistic load evaluation and life prediction evaluations are also described to illustrate the effectiveness of the coupled model approach.

  15. Axial flow heat exchanger devices and methods for heat transfer using axial flow devices

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

    Koplow, Jeffrey P.

    Systems and methods described herein are directed to rotary heat exchangers configured to transfer heat to a heat transfer medium flowing in substantially axial direction within the heat exchangers. Exemplary heat exchangers include a heat conducting structure which is configured to be in thermal contact with a thermal load or a thermal sink, and a heat transfer structure rotatably coupled to the heat conducting structure to form a gap region between the heat conducting structure and the heat transfer structure, the heat transfer structure being configured to rotate during operation of the device. In example devices heat may be transferredmore » across the gap region from a heated axial flow of the heat transfer medium to a cool stationary heat conducting structure, or from a heated stationary conducting structure to a cool axial flow of the heat transfer medium.« less

  16. Method of controlling switching of a multiphase inductor-converter bridge. [Patent application

    DOEpatents

    Kustom, R.L.; Fuja, R.E.

    In an inductor-convertor circuit for transferring electrical energy between a storage coil and a load coil through a storage thyristor bridge, a load thyristor bridge, and a set of commutating capacitors, operation is improved by a method of changing the rate of delivery of energy in a given direction. The change in rate corresponds to a predetermined change in phase angle between the load bridge and the storage bridge, and comprises changing the phase of the bridge by two steps, each equal to half the predetermined change and occurring 180/sup 0/ apart. The method assures commutation and minimizes imbalances that lead otherwise to overvoltages. 11 figures.

  17. Identifying and overcoming the effect of mass transfer limitation on decreased yield in enzymatic hydrolysis of lignocellulose at high solid concentrations.

    PubMed

    Du, Jian; Cao, Yuan; Liu, Guodong; Zhao, Jian; Li, Xuezhi; Qu, Yinbo

    2017-04-01

    Cellulose conversion decreases significantly with increasing solid concentrations during enzymatic hydrolysis of insoluble lignocellulosic materials. Here, mass transfer limitation was identified as a significant determining factor of this decrease by studying the hydrolysis of delignified corncob residue in shake flask, the most used reaction vessel in bench scale. Two mass transfer efficiency-related factors, mixing speed and flask filling, were shown to correlate closely with cellulose conversion at solid loadings higher than 15% DM. The role of substrate characteristics in mass transfer performance was also significant, which was revealed by the saccharification of two corn stover substrates with different pretreatment methods at the same solid loading. Several approaches including premix, fed-batch operation, and particularly the use of horizontal rotating reactor were shown to be valid in facilitating cellulose conversion via improving mass transfer efficiency at solid concentrations higher than 15% DM. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Laboratory techniques for human embryos.

    PubMed

    Geber, Selmo; Sales, Liana; Sampaio, Marcos A C

    2002-01-01

    This review is concerned with laboratory techniques needed for assisted conception, particularly the handling of gametes and embryos. Such methods are being increasingly refined. Successive stages of fertilization and embryogenesis require especial care, and often involve the use of micromanipulative methods for intracytoplasmic sperm injection (ICSI) or preimplantation genetic diagnosis. Embryologists must take responsibility for gamete collection and preparation, and for deciding on the means of insemination or ICSI. Embryos must be assessed in culture, during the 1-cell, cleaving and morula/blastocyst stages, and classified according to quality. Co-culture methods may be necessary. The best embryos for transfer must be selected and loaded into the transfer catheter. Embryos not transferred must be cryopreserved, which demands the correct application of current methods of media preparation, seeding and the correct speed for cooling and warming. Before too long, methods of detecting abnormal embryos and avoiding their transfer may become widespread.

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

    Kar, Durga P.; Nayak, Praveen P.; Bhuyan, Satyanarayan

    In order to power or charge electronic devices wirelessly, a bi-directional wireless power transfer method has been proposed and experimentally investigated. In the proposed design, two receiving coils are used on both sides of a transmitting coil along its central axis to receive the power wirelessly from the generated magnetic fields through strongly coupled magnetic resonance. It has been observed experimentally that the maximum power transfer occurs at the operating resonant frequency for optimum electric load connected across the receiving coils on both side. The optimum wireless power transfer efficiency is 88% for the bi-directional power transfer technique compared 84%more » in the one side receiver system. By adopting the developed bi-directional power transfer method, two electronic devices can be powered up or charged simultaneously instead of a single device through usual one side receiver system without affecting the optimum power transfer efficiency.« less

  20. The effects of individual differences, prior experience and cognitive load on the transfer of dynamic decision-making performance.

    PubMed

    Nicholson, Brad; O'Hare, David

    2014-01-01

    Situational awareness is recognised as an important factor in the performance of individuals and teams in dynamic decision-making (DDM) environments (Salmon et al. 2014 ). The present study was designed to investigate whether the scores on the WOMBAT™ Situational Awareness and Stress Tolerance Test (Roscoe and North 1980 ) would predict the transfer of DDM performance from training under different levels of cognitive load to a novel situation. Participants practised a simulated firefighting task under either low or high conditions of cognitive load and then performed a (transfer) test in an alternative firefighting environment under an intermediate level of cognitive load. WOMBAT™ test scores were a better predictor of DDM performance than scores on the Raven Matrices. Participants with high WOMBAT™ scores performed better regardless of their training condition. Participants with recent gaming experience who practised under low cognitive load showed better practice phase performance but worse transfer performance than those who practised under high cognitive load. The relationship between task experience, situational awareness ability, cognitive load and the transfer of dynamic decision-making (DDM) performance was investigated. Results showed that the WOMBAT™ test predicted transfer of DDM performance regardless of task cognitive load. The effects of cognitive load on performance varied according to previous task-relevant experience.

  1. Vehicle anti-rollover control strategy based on load transferring rate

    NASA Astrophysics Data System (ADS)

    Dai, W. T.; Du, H. Q.; Zhang, L.

    2018-03-01

    When vehicles is drived on a low adhesion road or going on a high speed and sharp turn, it is prone to product some lateral stability problems, such as lateral sideslip or rollover. In order to improve the vehicle anti-rollover stability under these limited conditions, a SUV vehicle model with high mass center was built based on the software of CarSim and the rollover stability controller was designed using the static threshold value method for the lateral load transferring rate (LTR). The simulations are shown that the vehicle anti-rollover stability under limit conditions is improved using the SUV model.

  2. Comparative analysis on flexibility requirements of typical Cryogenic Transfer lines

    NASA Astrophysics Data System (ADS)

    Jadon, Mohit; Kumar, Uday; Choukekar, Ketan; Shah, Nitin; Sarkar, Biswanath

    2017-04-01

    The cryogenic systems and their applications; primarily in large Fusion devices, utilize multiple cryogen transfer lines of various sizes and complexities to transfer cryogenic fluids from plant to the various user/ applications. These transfer lines are composed of various critical sections i.e. tee section, elbows, flexible components etc. The mechanical sustainability (under failure circumstances) of these transfer lines are primary requirement for safe operation of the system and applications. The transfer lines need to be designed for multiple design constraints conditions like line layout, support locations and space restrictions. The transfer lines are subjected to single load and multiple load combinations, such as operational loads, seismic loads, leak in insulation vacuum loads etc. [1]. The analytical calculations and flexibility analysis using professional software are performed for the typical transfer lines without any flexible component, the results were analysed for functional and mechanical load conditions. The failure modes were identified along the critical sections. The same transfer line was then refurbished with the flexible components and analysed for failure modes. The flexible components provide additional flexibility to the transfer line system and make it safe. The results obtained from the analytical calculations were compared with those obtained from the flexibility analysis software calculations. The optimization of the flexible component’s size and selection was performed and components were selected to meet the design requirements as per code.

  3. Composite load spectra for select space propulsion structural components

    NASA Technical Reports Server (NTRS)

    Newell, J. F.; Ho, H. W.; Kurth, R. E.

    1991-01-01

    The work performed to develop composite load spectra (CLS) for the Space Shuttle Main Engine (SSME) using probabilistic methods. The three methods were implemented to be the engine system influence model. RASCAL was chosen to be the principal method as most component load models were implemented with the method. Validation of RASCAL was performed. High accuracy comparable to the Monte Carlo method can be obtained if a large enough bin size is used. Generic probabilistic models were developed and implemented for load calculations using the probabilistic methods discussed above. Each engine mission, either a real fighter or a test, has three mission phases: the engine start transient phase, the steady state phase, and the engine cut off transient phase. Power level and engine operating inlet conditions change during a mission. The load calculation module provides the steady-state and quasi-steady state calculation procedures with duty-cycle-data option. The quasi-steady state procedure is for engine transient phase calculations. In addition, a few generic probabilistic load models were also developed for specific conditions. These include the fixed transient spike model, the poison arrival transient spike model, and the rare event model. These generic probabilistic load models provide sufficient latitude for simulating loads with specific conditions. For SSME components, turbine blades, transfer ducts, LOX post, and the high pressure oxidizer turbopump (HPOTP) discharge duct were selected for application of the CLS program. They include static pressure loads and dynamic pressure loads for all four components, centrifugal force for the turbine blade, temperatures of thermal loads for all four components, and structural vibration loads for the ducts and LOX posts.

  4. MIT Orbital Transfer Vehicle (MOTV): CASTOR Satellite: Design Document

    DTIC Science & Technology

    2010-11-18

    65 Table 2.2-3: MEMS IMU RATE Sensor ...................................................................................... 66 Table 2.2...either high power mode, providing about 4 mN of thrust, or in off mode, in which the cathode will remain heated . The propulsion system will also...subsections: ICD Block Diagram, Heat Transfer Method, Thermal Path, Heat Loads and Fluxes, and Modeling. The ICD Block Diagram identifies the connections

  5. A system-level mathematical model for evaluation of power train performance of load-leveled electric-vehicles

    NASA Technical Reports Server (NTRS)

    Purohit, G. P.; Leising, C. J.

    1984-01-01

    The power train performance of load leveled electric vehicles can be compared with that of nonload leveled systems by use of a simple mathematical model. This method of measurement involves a number of parameters including the degree of load leveling and regeneration, the flywheel mechanical to electrical energy fraction, and efficiencies of the motor, generator, flywheel, and transmission. Basic efficiency terms are defined and representative comparisons of a variety of systems are presented. Results of the study indicate that mechanical transfer of energy into and out of the flywheel is more advantageous than electrical transfer. An optimum degree of load leveling may be achieved in terms of the driving cycle, battery characteristics, mode of mechanization, and the efficiency of the components. For state of the art mechanically coupled flyheel systems, load leveling losses can be held to a reasonable 10%; electrically coupled systems can have losses that are up to six times larger. Propulsion system efficiencies for mechanically coupled flywheel systems are predicted to be approximately the 60% achieved on conventional nonload leveled systems.

  6. Test load verification through strain data analysis

    NASA Technical Reports Server (NTRS)

    Verderaime, V.; Harrington, F.

    1995-01-01

    A traditional binding acceptance criterion on polycrystalline structures is the experimental verification of the ultimate factor of safety. At fracture, the induced strain is inelastic and about an order-of-magnitude greater than designed for maximum expected operational limit. At this extreme strained condition, the structure may rotate and displace at the applied verification load such as to unknowingly distort the load transfer into the static test article. Test may result in erroneously accepting a submarginal design or rejecting a reliable one. A technique was developed to identify, monitor, and assess the load transmission error through two back-to-back surface-measured strain data. The technique is programmed for expediency and convenience. Though the method was developed to support affordable aerostructures, the method is also applicable for most high-performance air and surface transportation structural systems.

  7. Friction-reducing devices for lateral patient transfers: a clinical evaluation.

    PubMed

    Baptiste, Andrea; Boda, Sruthi V; Nelson, Audrey L; Lloyd, John D; Lee, William E

    2006-04-01

    The purpose of this study was to assess the performance of lateral transfer devices compared with the traditional draw sheet method in acute care settings through subjective feedback of caregivers actually using the devices. Every 2 weeks, the eight participating acute care units each received one of the devices, which had been randomly selected. Data were collected through caregiver surveys, which rated comfort, ease of use, perceived injury risk, time efficiency, and patient safety. An overall performance rating was calculated as the sum of these five categories. Caregivers rated air-assisted devices significantly higher (p < .05) than other devices. Lateral transfer devices are recommended over the traditional draw sheet method for performing lateral patient transfers. These friction-reducing devices are a cost-effective solution to the load of lateral patient transfers and should be favorably considered when purchasing patient-handling technologies.

  8. Resistive Exercise Device

    NASA Technical Reports Server (NTRS)

    Smith, Damon C. (Inventor)

    2005-01-01

    An exercise device 10 is particularly well suited for use in low gravity environments, and includes a frame 12 with plurality of resistance elements 30,82 supported in parallel on the frame. A load transfer member 20 is moveable relative to the frame for transferring the applied force to the free end of each captured resistance element. Load selection template 14 is removably secured both to the load transfer member, and a plurality of capture mechanisms engage the free end of corresponding resistance elements. The force applying mechanism 53 may be a handle, harness or other user interface for applying a force to move the load transfer member.

  9. Transfer of movement sequences: bigger is better.

    PubMed

    Dean, Noah J; Kovacs, Attila J; Shea, Charles H

    2008-02-01

    Experiment 1 was conducted to determine if proportional transfer from "small to large" scale movements is as effective as transferring from "large to small." We hypothesize that the learning of larger scale movement will require the participant to learn to manage the generation, storage, and dissipation of forces better than when practicing smaller scale movements. Thus, we predict an advantage for transfer of larger scale movements to smaller scale movements relative to transfer from smaller to larger scale movements. Experiment 2 was conducted to determine if adding a load to a smaller scale movement would enhance later transfer to a larger scale movement sequence. It was hypothesized that the added load would require the participants to consider the dynamics of the movement to a greater extent than without the load. The results replicated earlier findings of effective transfer from large to small movements, but consistent with our hypothesis, transfer was less effective from small to large (Experiment 1). However, when a load was added during acquisition transfer from small to large was enhanced even though the load was removed during the transfer test. These results are consistent with the notion that the transfer asymmetry noted in Experiment 1 was due to factors related to movement dynamics that were enhanced during practice of the larger scale movement sequence, but not during the practice of the smaller scale movement sequence. The findings that the movement structure is unaffected by transfer direction but the movement dynamics are influenced by transfer direction is consistent with hierarchal models of sequence production.

  10. Pull-out testing facility for geosynthetics.

    DOT National Transportation Integrated Search

    1992-11-01

    The considerable increase in using geosynthetics in soil reinforcement made it necessary to develop methods of measuring the interaction properties and modeling load transfer in reinforced-soil structures. The large number of factors that influence t...

  11. Using a Three-Step Method in a Calculus Class: Extending the Worked Example

    ERIC Educational Resources Information Center

    Miller, David

    2010-01-01

    This article discusses a three-step method that was used in a college calculus course. The three-step method was developed to help students understand the course material and transition to be more independent learners. In addition, the method helped students to transfer concepts from short-term to long-term memory while lowering cognitive load.…

  12. Using the intrinsic properties of silicon micro-ring modulators for characterization of RF termination

    NASA Astrophysics Data System (ADS)

    Wang, Zhao; Knights, Andrew P.

    2017-02-01

    We describe a direct experimental method to determine the effective driving voltage (Vpp) applied to a silicon photonic modulator possessing an impedance mismatch between the unterminated capacitive load and input source. This method thus permits subsequent estimation of the power consumption of an imperfectly terminated device as well as a deduction of load impedance for optimization of termination design. The capacitive load in this paper is a silicon micro-ring modulator with an integrated p-n junction acting as a phase shifter. The RF reflection under high-speed drive is directly determined from observation of the eye-diagram following measurement of the power transfer function for various junction bias.

  13. 77 FR 50921 - Safety Zone: Bay Bridge Load Transfer Safety Zone, San Francisco Bay, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-23

    ...-AA00 Safety Zone: Bay Bridge Load Transfer Safety Zone, San Francisco Bay, San Francisco, CA AGENCY... the Bay Bridge Load Transfer Safety Zone from August 1, 2012 through October 31, 2012. This safety... Bay Bridge from the temporary suspension arrangement to the permanent suspension arrangement, the...

  14. CFD and Thermo Mechanical Analysis on Effect of Curved vs Step Surface in IC Engine Cylinder Head

    NASA Astrophysics Data System (ADS)

    Balaji, S.; Ganesh, N.; Kumarasamy, A.

    2017-05-01

    Current research in IC engines mainly focus on various methods to achieve higher efficiency and high specific power. As a single design parameter, combustion chamber peak spring pressure has increased more than before. Apart from the structural aspects of withstanding these loads, designer faces challenges of resolving thermal aspects of cylinder head. Methods to enhance the heat transfer without compromising load withstanding capability are being constantly explored. Conventional cylinder heads have got sat inner surface. In this paper we have suggested a modification in inner surface to enhance the heat transfer capability. To increase the heat transfer rate, inner same deck surface is configured as a curved and stepped surface instead of sat. We have reported the effectiveness of extend of curvature in the inner same deck surface in a different technical paper. Here, we are making a direct comparison between stepped and curved surface only. From this analysis it has been observed that curved surface reduces the ame deck temperature considerably without compromising the structural strength factors compared to step and sat surface.

  15. Methods of computing steady-state voltage stability margins of power systems

    DOEpatents

    Chow, Joe Hong; Ghiocel, Scott Gordon

    2018-03-20

    In steady-state voltage stability analysis, as load increases toward a maximum, conventional Newton-Raphson power flow Jacobian matrix becomes increasingly ill-conditioned so power flow fails to converge before reaching maximum loading. A method to directly eliminate this singularity reformulates the power flow problem by introducing an AQ bus with specified bus angle and reactive power consumption of a load bus. For steady-state voltage stability analysis, the angle separation between the swing bus and AQ bus can be varied to control power transfer to the load, rather than specifying the load power itself. For an AQ bus, the power flow formulation is only made up of a reactive power equation, thus reducing the size of the Jacobian matrix by one. This reduced Jacobian matrix is nonsingular at the critical voltage point, eliminating a major difficulty in voltage stability analysis for power system operations.

  16. 49 CFR 1242.74 - Adjusting and transferring loads, and car loading devices and grain doors (accounts XX-33-71 and...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Adjusting and transferring loads, and car loading devices and grain doors (accounts XX-33-71 and XX-33-72). 1242.74 Section 1242.74 Transportation Other... loads, and car loading devices and grain doors (accounts XX-33-71 and XX-33-72). These accounts pertain...

  17. Camphor-Enabled Transfer and Mechanical Testing of Centimeter-Scale Ultrathin Films.

    PubMed

    Wang, Bin; Luo, Da; Li, Zhancheng; Kwon, Youngwoo; Wang, Meihui; Goo, Min; Jin, Sunghwan; Huang, Ming; Shen, Yongtao; Shi, Haofei; Ding, Feng; Ruoff, Rodney S

    2018-05-21

    Camphor is used to transfer centimeter-scale ultrathin films onto custom-designed substrates for mechanical (tensile) testing. Compared to traditional transfer methods using dissolving/peeling to remove the support-layers, camphor is sublimed away in air at low temperature, thereby avoiding additional stress on the as-transferred films. Large-area ultrathin films can be transferred onto hollow substrates without damage by this method. Tensile measurements are made on centimeter-scale 300 nm-thick graphene oxide film specimens, much thinner than the ≈2 μm minimum thickness of macroscale graphene-oxide films previously reported. Tensile tests were also done on two different types of large-area samples of adlayer free CVD-grown single-layer graphene supported by a ≈100 nm thick polycarbonate film; graphene stiffens this sample significantly, thus the intrinsic mechanical response of the graphene can be extracted. This is the first tensile measurement of centimeter-scale monolayer graphene films. The Young's modulus of polycrystalline graphene ranges from 637 to 793 GPa, while for near single-crystal graphene, it ranges from 728 to 908 GPa (folds parallel to the tensile loading direction) and from 683 to 775 GPa (folds orthogonal to the tensile loading direction), demonstrating the mechanical performance of large-area graphene in a size scale relevant to many applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. 33 CFR 154.510 - Loading arms.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Loading arms. 154.510 Section 154... FACILITIES TRANSFERRING OIL OR HAZARDOUS MATERIAL IN BULK Equipment Requirements § 154.510 Loading arms. (a) Each mechanical loading arm used for transferring oil or hazardous material and placed into service...

  19. 33 CFR 154.510 - Loading arms.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Loading arms. 154.510 Section 154... FACILITIES TRANSFERRING OIL OR HAZARDOUS MATERIAL IN BULK Equipment Requirements § 154.510 Loading arms. (a) Each mechanical loading arm used for transferring oil or hazardous material and placed into service...

  20. 33 CFR 154.510 - Loading arms.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Loading arms. 154.510 Section 154... FACILITIES TRANSFERRING OIL OR HAZARDOUS MATERIAL IN BULK Equipment Requirements § 154.510 Loading arms. (a) Each mechanical loading arm used for transferring oil or hazardous material and placed into service...

  1. Electric power distribution and load transfer system

    NASA Technical Reports Server (NTRS)

    Bradford, Michael P. (Inventor); Parkinson, Gerald W. (Inventor); Grant, Ross M. (Inventor)

    1987-01-01

    A power distribution system includes a plurality of power sources and load transfer units including transistors and diodes connected in series and leading to a common power output, each of the transistors being controller switchable subject to voltage levels of the respective input and output sides of said transistors, and the voltage and current level of said common power output. The system is part of an interconnection scheme in which all but one of the power sources is connected to a single load transfer unit, enabling the survival of at least a single power source with the failure of one of the load transfer units.

  2. Electric power distribution and load transfer system

    NASA Technical Reports Server (NTRS)

    Bradford, Michael P. (Inventor); Parkinson, Gerald W. (Inventor); Grant, Ross M. (Inventor)

    1989-01-01

    A power distribution system includes a plurality of power sources and load transfer units including transistors and diodes connected in series and leading to a common power output, each of the transistors being controller switchable subject to voltage levels of the respective input and output sides of said transistors, and the voltage and current level of said common power output. The system is part of an interconnection scheme in which all but one of the power sources is connected to a single load transfer unit, enabling the survival of at least a single power source with the failure of one of the load transfer units.

  3. Thermally determining flow and/or heat load distribution in parallel paths

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

    Chainer, Timothy J.; Iyengar, Madhusudan K.; Parida, Pritish R.

    A method including obtaining calibration data for at least one sub-component in a heat transfer assembly, wherein the calibration data comprises at least one indication of coolant flow rate through the sub-component for a given surface temperature delta of the sub-component and a given heat load into said sub-component, determining a measured heat load into the sub-component, determining a measured surface temperature delta of the sub-component, and determining a coolant flow distribution in a first flow path comprising the sub-component from the calibration data according to the measured heat load and the measured surface temperature delta of the sub-component.

  4. Thermally determining flow and/or heat load distribution in parallel paths

    DOEpatents

    Chainer, Timothy J.; Iyengar, Madhusudan K.; Parida, Pritish R.

    2016-12-13

    A method including obtaining calibration data for at least one sub-component in a heat transfer assembly, wherein the calibration data comprises at least one indication of coolant flow rate through the sub-component for a given surface temperature delta of the sub-component and a given heat load into said sub-component, determining a measured heat load into the sub-component, determining a measured surface temperature delta of the sub-component, and determining a coolant flow distribution in a first flow path comprising the sub-component from the calibration data according to the measured heat load and the measured surface temperature delta of the sub-component.

  5. Method for lowering the VOCS emitted during drying of wood products

    DOEpatents

    Banerjee, Sujit; Boerner, James Robert; Su, Wei

    2000-01-01

    The present invention is directed to a method for removal of VOCs from wood products prior to drying the wood products. The method of the invention includes the steps of providing a chamber having an opening for receiving wood and loading the chamber with green wood. The wood is loaded to an extent sufficient to provide a limited headspace in the chamber. The chamber is then closed and the wood is heated in the chamber for a time and at a temperature sufficient to saturate the headspace with moisture and to substantially transfer VOCs from the wood product to the moisture in the headspace.

  6. Car Transfer and Wheelchair Loading Techniques in Independent Drivers with Paraplegia

    PubMed Central

    Haubert, Lisa Lighthall; Mulroy, Sara J.; Hatchett, Patricia E.; Eberly, Valerie J.; Maneekobkunwong, Somboon; Gronley, Joanne K.; Requejo, Philip S.

    2015-01-01

    Car transfers and wheelchair (WC) loading are crucial for independent community participation in persons with complete paraplegia from spinal cord injury, but are complex, physically demanding, and known to provoke shoulder pain. This study aimed to describe techniques and factors influencing car transfer and WC loading for individuals with paraplegia driving their own vehicles and using their personal WCs. Sedans were the most common vehicle driven (59%). Just over half (52%) of drivers place their right leg only into the vehicle prior to transfer. Overall, the leading hand was most frequently placed on the driver’s seat (66%) prior to transfer and the trailing hand was most often place on the WC seat (48%). Vehicle height influenced leading hand placement but not leg placement such that drivers of higher profile vehicles were more likely to place their hand on the driver’s seat than those who drove sedans. Body lift time was negatively correlated with level of injury and age and positively correlated with vehicle height and shoulder abduction strength. Drivers who transferred with their leading hand on the steering wheel had significantly higher levels of shoulder pain than those who placed their hand on the driver’s seat or overhead. The majority of participants used both hands (62%) to load their WC frame, and overall, most loaded their frame into the back (62%) vs. the front seat. Sedan drivers were more likely to load their frame into the front seat than drivers of higher profile vehicles (53 vs. 17%). Average time to load the WC frame (10.7 s) was 20% of the total WC loading time and was not related to shoulder strength, frame weight, or demographic characteristics. Those who loaded their WC frame into the back seat had significantly weaker right shoulder internal rotators. Understanding car transfers and WC loading in independent drivers is crucial to prevent shoulder pain and injury and preserve community participation. PMID:26442253

  7. Biaxial (Tension-Torsion) Testing of an Oxide/Oxide Ceramic Matrix Composite

    DTIC Science & Technology

    2013-03-01

    estimation algorithms and constants . . . . . . . . . . . . . 61 4.27 Biaxial (tension-torsion) load spreadsheet with independent axial load and torsion...through the composite and provides the main load - bearing capability. The interaction of the two (or more) phases takes place in the interface. The...transfer loads between fibers[15]. The fiber-to-fiber load transfer mechanism provided by the matrix plays a major role in the load - bearing properties of the

  8. Alternative methods to model frictional contact surfaces using NASTRAN

    NASA Technical Reports Server (NTRS)

    Hoang, Joseph

    1992-01-01

    Elongated (slotted) holes have been used extensively for the integration of equipment into Spacelab racks. In the past, this type of interface has been modeled assuming that there is not slippage between contact surfaces, or that there is no load transfer in the direction of the slot. Since the contact surfaces are bolted together, the contact friction provides a load path determined by the normal applied force (bolt preload) and the coefficient of friction. Three alternate methods that utilize spring elements, externally applied couples, and stress dependent elements are examined to model the contacted surfaces. Results of these methods are compared with results obtained from methods that use GAP elements and rigid elements.

  9. Poynting vector analysis for wireless power transfer between magnetically coupled coils with different loads.

    PubMed

    Guo, Yunsheng; Li, Jiansheng; Hou, Xiaojuan; Lv, Xiaolong; Liang, Hao; Zhou, Ji; Wu, Hongya

    2017-04-07

    Wireless power transfer is a nonradiative type of transmission that is performed in the near-field region. In this region, the electromagnetic fields that are produced by both the transmitting and receiving coils are evanescent fields, which should not transmit energy. This then raises the question of how the energy can be transferred. Here we describe a theoretical study of the two evanescent field distributions at different terminal loads. It is shown that the essential principle of wireless energy transfer is the superposition of the two evanescent fields, and the resulting superimposed field is mediated through the terminal load. If the terminal load is either capacitive or inductive, then the superimposed field cannot transfer the energy because its Poynting vector is zero; in contrast, if the load is resistive, energy can then be conveyed from the transmitting coil to the receiving coil. The simulation results for the magnetic field distributions and the time-domain current waveforms agree very well with the results of the theoretical analysis. This work thus provides a comprehensive understanding of the energy transfer mechanism involved in the magnetic resonant coupling system.

  10. 40 CFR 63.2338 - What parts of my plant does this subpart cover?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... transfer racks at which organic liquids are loaded into or unloaded out of transport vehicles and/or...) Storage tanks storing organic liquids; (ii) Transfer racks loading or unloading organic liquids; (iii... and a transfer rack subject to this subpart; and (v) Pipelines that transfer organic liquids directly...

  11. Elastic plate spallation

    NASA Technical Reports Server (NTRS)

    Oline, L.; Medaglia, J.

    1972-01-01

    The dynamic finite element method was used to investigate elastic stress waves in a plate. Strain displacement and stress strain relations are discussed along with the stiffness and mass matrix. The results of studying point load, and distributed load over small, intermediate, and large radii are reported. The derivation of finite element matrices, and the derivation of lumped and consistent matrices for one dimensional problems with Laplace transfer solutions are included. The computer program JMMSPALL is also included.

  12. [Comparison of different methods in dealing with HIV viral load data with diversified missing value mechanism on HIV positive MSM].

    PubMed

    Jiang, Z; Dou, Z; Song, W L; Xu, J; Wu, Z Y

    2017-11-10

    Objective: To compare results of different methods: in organizing HIV viral load (VL) data with missing values mechanism. Methods We used software SPSS 17.0 to simulate complete and missing data with different missing value mechanism from HIV viral loading data collected from MSM in 16 cities in China in 2013. Maximum Likelihood Methods Using the Expectation and Maximization Algorithm (EM), regressive method, mean imputation, delete method, and Markov Chain Monte Carlo (MCMC) were used to supplement missing data respectively. The results: of different methods were compared according to distribution characteristics, accuracy and precision. Results HIV VL data could not be transferred into a normal distribution. All the methods showed good results in iterating data which is Missing Completely at Random Mechanism (MCAR). For the other types of missing data, regressive and MCMC methods were used to keep the main characteristic of the original data. The means of iterating database with different methods were all close to the original one. The EM, regressive method, mean imputation, and delete method under-estimate VL while MCMC overestimates it. Conclusion: MCMC can be used as the main imputation method for HIV virus loading missing data. The iterated data can be used as a reference for mean HIV VL estimation among the investigated population.

  13. Measurements of the apparent thermal conductivity of multi-layer insulation between 20 K and 90 K

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

    Hurd, Joseph A.; Van Sciver, Steven W.

    NASA has the need to efficiently store cryogenic propellants in space for long periods of time. One method to improve storage efficiency is to use multi-layer insulation (MLI), a technique that minimizes the boiling rate due to radiation heat transfer. Typically, the thermal performance of MLI is determined by measuring the rate of evaporation of liquid nitrogen from a calibrated cryostat. The main limitation with this method is that testing conditions are restricted by the boiling temperature of the LN{sub 2}, which may not match the requirements of the application. The Multi-Layer Insulation Thermal Conductivity Experiment (MIKE) at the Nationalmore » High Magnetic Field Laboratory is capable of measuring the effective thermal conductivity of MLI at variable boundary temperatures. MIKE uses cryo-refrigerators to control boundary temperatures in the calorimeter and a calibrated thermal link to measure the heat load. To make the measurements requested by NASA, MIKE needed to be recalibrated for the 20 K to 90 K range. Also, due to the expectation of a lower heat transfer rate, the heat load support rod material was changed to one with a lower thermal conductivity to ensure the temperature difference seen on the cold rod could be measurable at the estimated heat load. Presented are the alterations to MIKE including calibration data and heat load measurements on new load-bearing MLI supplied by NASA.« less

  14. Reconfigurable Resonant Regulating Rectifier With Primary Equalization for Extended Coupling- and Loading-Range in Bio-Implant Wireless Power Transfer.

    PubMed

    Li, Xing; Meng, Xiaodong; Tsui, Chi-Ying; Ki, Wing-Hung

    2015-12-01

    Wireless power transfer using reconfigurable resonant regulating (R(3)) rectification suffers from limited range in accommodating varying coupling and loading conditions. A primary-assisted regulation principle is proposed to mitigate these limitations, of which the amplitude of the rectifier input voltage on the secondary side is regulated by accordingly adjusting the voltage amplitude Veq on the primary side. A novel current-sensing method and calibration scheme track Veq on the primary side. A ramp generator simultaneously provides three clock signals for different modules. Both the primary equalizer and the R(3) rectifier are implemented as custom integrated circuits fabricated in a 0.35 μm CMOS process, with the global control implemented in FPGA. Measurements show that with the primary equalizer, the workable coupling and loading ranges are extended by 250% at 120 mW load and 300% at 1.2 cm coil distance compared to the same system without the primary equalizer. A maximum rectifier efficiency of 92.5% and a total system efficiency of 62.4% are demonstrated.

  15. High-resolution slab gel isoelectric focusing: methods for quantitative electrophoretic transfer and immunodetection of proteins as applied to the study of the multiple isoelectric forms of ornithine decarboxylase.

    PubMed

    Reddy, S G; Cochran, B J; Worth, L L; Knutson, V P; Haddox, M K

    1994-04-01

    A high-resolution isoelectric focusing vertical slab gel method which can resolve proteins which differ by a single charge was developed and this method was applied to the study of the multiple isoelectric forms of ornithine decarboxylase. Separation of proteins at this high level of resolution was achieved by increasing the ampholyte concentration in the gels to 6%. Various lots of ampholytes, from the same or different commercial sources, differed significantly in their protein binding capacity. Ampholytes bound to proteins interfered both with the electrophoretic transfer of proteins from the gel to immunoblotting membranes and with the ability of antibodies to interact with proteins on the immunoblotting membranes. Increasing the amount of protein loaded into a gel lane also decreased the efficiency of the electrophoretic transfer and immunodetection. To overcome these problems, both gel washing and gel electrophoretic transfer protocols for disrupting the ampholyte-protein binding and enabling a quantitative electrophoretic transfer of proteins were developed. Two gel washing procedures, with either thiocyanate or borate buffers, and a two-step electrophoretic transfer method are described. The choice of which method to use to optimally disrupt the ampholyte-protein binding was found to vary with each lot of ampholytes employed.

  16. [New methods for determining the relative load due to physical effort of the human body].

    PubMed

    Szubert, Józef; Szubert, Sławomir; Koszada-Włodarczyk, Wiesława; Bortkiewicz, Alicja

    2014-01-01

    The relative physical load (% VO2max) is the quotient of oxygen uptake (Vo2) during physical effort and maximum oxygen uptake (VO2max) by the human body. For this purpose the stress test must be performed. The relative load shows a high correlation with minute ventilation, cardiac output, heart rate, stroke volume, increased concentrations of catecholamines in the blood, inner temperature, weight, height and human body surface area. The relative load is a criterion for the maximum workloads admissible for healthy and sick workers. Besides, the classification of effort can be more precise when based on the relative load than on the energy output. Based on our own and international empirical evidence and the laws of heat transfer and fluid mechanics, a model of temperature control system has been developed, involving the elements of human cardiovascular and respiratory systems. Using this model, we have been able to develop our own methods of determining the relative load, applying only the body core temperature (Tw) or heart rate within one minute (HR), body mass (m), height (H), and body surface area (AD) instead of VO,max. The values of the relative physical load (% VO2max) obtained by using our own methods do not differ significantly from those obtained by other methods and by other researchers. The developed methods for determining the relative physical load (% VO2max) do not require the exercise test to be performed, therefore, they may be considered (after verification in an experimental study) a feasible alternative to current methods.

  17. Survey of aircraft electrical power systems

    NASA Technical Reports Server (NTRS)

    Lee, C. H.; Brandner, J. J.

    1972-01-01

    Areas investigated include: (1) load analysis; (2) power distribution, conversion techniques and generation; (3) design criteria and performance capabilities of hydraulic and pneumatic systems; (4) system control and protection methods; (5) component and heat transfer systems cooling; and (6) electrical system reliability.

  18. Loading an Optical Trap with Diamond Nanocrystals Containing Nitrogen-Vacancy Centers from a Surface

    NASA Astrophysics Data System (ADS)

    Hsu, Jen-Feng; Ji, Peng; Dutt, M. V. Gurudev; D'Urso, Brian R.

    2015-03-01

    We present a simple and effective method of loading particles into an optical trap. Our primary application of this method is loading photoluminescent material, such as diamond nanocrystals containing nitrogen-vacancy (NV) centers, for coupling the mechanical motion of the trapped crystal with the spin of the NV centers. Highly absorptive material at the trapping laser frequency, such as tartrazine dye, is used as media to attach nanodiamonds and burn into a cloud of air-borne particles as the material is swept near the trapping laser focus on a glass slide. Particles are then trapped with the laser used for burning or transferred to a second laser trap at a different wavelength. Evidence of successful loading diamond nanocrystals into the trap presented includes high sensitivity of the photoluminecscence (PL) to the excitation laser and the PL spectra of the optically trapped particles

  19. Load characteristics of wireless power transfer system with different resonant types and resonator numbers

    NASA Astrophysics Data System (ADS)

    Zhang, Yiming; Zhao, Zhengming; Chen, Kainan; Fan, Jun

    2017-05-01

    Wireless Power Transfer (WPT) has been the research focus and applied in many fields. Normally power is transferred wirelessly to charge the battery, which requires specific load characteristics. The load characteristics are essential for the design and operation of the WPT system. This paper investigates the load characteristics of the WPT system with different resonant types and resonator numbers. It is found that in a WPT system with series or LCL resonance under a constant voltage source, the load characteristic is determined by the number of inductors. Even number of inductors results in a constant current characteristic and odd number constant voltage characteristic. Calculations, simulations, and experiments verify the analysis.

  20. Achieving the Promise of Therapeutic Extracellular Vesicles: The Devil is in Details of Therapeutic Loading.

    PubMed

    Sutaria, Dhruvitkumar S; Badawi, Mohamed; Phelps, Mitch A; Schmittgen, Thomas D

    2017-05-01

    Extracellular vesicles (EVs) represent a class of cell secreted organelles which naturally contain biomolecular cargo such as miRNA, mRNA and proteins. EVs mediate intercellular communication, enabling the transfer of functional nucleic acids from the cell of origin to the recipient cells. In addition, EVs make an attractive delivery vehicle for therapeutics owing to their increased stability in circulation, biocompatibility, low immunogenicity and toxicity profiles. EVs can also be engineered to display targeting moieties on their surfaces which enables targeting to desired tissues, organs or cells. While much has been learned on the role of EVs as cell communicators, the field of therapeutic EV application is currently under development. Critical to the future success of EV delivery system is the description of methods by which therapeutics can be successfully and efficiently loaded within the EVs. Two methods of loading of EVs with therapeutic cargo exist, endogenous and exogenous loading. We have therefore focused this review on describing the various published approaches for loading EVs with therapeutics.

  1. Composite load spectra for select space propulsion structural components

    NASA Technical Reports Server (NTRS)

    Newell, J. F.; Kurth, R. E.; Ho, H.

    1986-01-01

    A multiyear program is performed with the objective to develop generic load models with multiple levels of progressive sophistication to simulate the composite (combined) load spectra that are induced in space propulsion system components, representative of Space Shuttle Main Engines (SSME), such as transfer ducts, turbine blades, and liquid oxygen (LOX) posts. Progress of the first year's effort includes completion of a sufficient portion of each task -- probabilistic models, code development, validation, and an initial operational code. This code has from its inception an expert system philosophy that could be added to throughout the program and in the future. The initial operational code is only applicable to turbine blade type loadings. The probabilistic model included in the operational code has fitting routines for loads that utilize a modified Discrete Probabilistic Distribution termed RASCAL, a barrier crossing method and a Monte Carlo method. An initial load model was developed by Battelle that is currently used for the slowly varying duty cycle type loading. The intent is to use the model and related codes essentially in the current form for all loads that are based on measured or calculated data that have followed a slowly varying profile.

  2. Heat-transfer and pressure measurements on a simulated elevon deflected 30 deg near flight conditions at Mach 7

    NASA Technical Reports Server (NTRS)

    Johnson, C. B.; Taylor, A. H.; Weinstein, I.

    1977-01-01

    Heat transfer rates and pressures were obtained on an elevon plate (deflected 30 deg) and a flat plate upstream of the elevon in an 8 foot high-temperature structures tunnel. The flight Reynolds number and flight total enthalpy for altitudes of 26.8 km and 28.7 km at Mach seven were duplicated. The heat transfer and pressure data were used to establish heating and pressure loads. The measured heating was compared with several theoretical predictions, and the closest agreement obtained with a Schultz-Grunow reference enthalpy method of calculation.

  3. Transfer Hydro-dehalogenation of Organic Halides Catalyzed by Ruthenium(II) Complex.

    PubMed

    You, Tingjie; Wang, Zhenrong; Chen, Jiajia; Xia, Yuanzhi

    2017-02-03

    A simple and efficient Ru(II)-catalyzed transfer hydro-dehalogenation of organic halides using 2-propanol solvent as the hydride source was reported. This methodology is applicable for hydro-dehalogenation of a variety of aromatic halides and α-haloesters and amides without additional ligand, and quantitative yields were achieved in many cases. The potential synthetic application of this method was demonstrated by efficient gram-scale transformation with catalyst loading as low as 0.5 mol %.

  4. Studies of aerothermal loads generated in regions of shock/shock interaction in hypersonic flow

    NASA Technical Reports Server (NTRS)

    Holden, Michael S.; Moselle, John R.; Lee, Jinho

    1991-01-01

    Experimental studies were conducted to examine the aerothermal characteristics of shock/shock/boundary layer interaction regions generated by single and multiple incident shocks. The presented experimental studies were conducted over a Mach number range from 6 to 19 for a range of Reynolds numbers to obtain both laminar and turbulent interaction regions. Detailed heat transfer and pressure measurements were made for a range of interaction types and incident shock strengths over a transverse cylinder, with emphasis on the 3 and 4 type interaction regions. The measurements were compared with the simple Edney, Keyes, and Hains models for a range of interaction configurations and freestream conditions. The complex flowfields and aerothermal loads generated by multiple-shock impingement, while not generating as large peak loads, provide important test cases for code prediction. The detailed heat transfer and pressure measurements proved a good basis for evaluating the accuracy of simple prediction methods and detailed numerical solutions for laminar and transitional regions or shock/shock interactions.

  5. Power electronic interface circuits for batteries and ultracapacitors in electric vehicles and battery storage systems

    DOEpatents

    King, Robert Dean; DeDoncker, Rik Wivina Anna Adelson

    1998-01-01

    A method and apparatus for load leveling of a battery in an electrical power system includes a power regulator coupled to transfer power between a load and a DC link, a battery coupled to the DC link through a first DC-to-DC converter and an auxiliary passive energy storage device coupled to the DC link through a second DC-to-DC converter. The battery is coupled to the passive energy storage device through a unidirectional conducting device whereby the battery can supply power to the DC link through each of the first and second converters when battery voltage exceeds voltage on the passive storage device. When the load comprises a motor capable of operating in a regenerative mode, the converters are adapted for transferring power to the battery and passive storage device. In this form, resistance can be coupled in circuit with the second DC-to-DC converter to dissipate excess regenerative power.

  6. Power electronic interface circuits for batteries and ultracapacitors in electric vehicles and battery storage systems

    DOEpatents

    King, R.D.; DeDoncker, R.W.A.A.

    1998-01-20

    A method and apparatus for load leveling of a battery in an electrical power system includes a power regulator coupled to transfer power between a load and a DC link, a battery coupled to the DC link through a first DC-to-DC converter and an auxiliary passive energy storage device coupled to the DC link through a second DC-to-DC converter. The battery is coupled to the passive energy storage device through a unidirectional conducting device whereby the battery can supply power to the DC link through each of the first and second converters when battery voltage exceeds voltage on the passive storage device. When the load comprises a motor capable of operating in a regenerative mode, the converters are adapted for transferring power to the battery and passive storage device. In this form, resistance can be coupled in circuit with the second DC-to-DC converter to dissipate excess regenerative power. 8 figs.

  7. Determination of hand soil loading, soil transfer, and particle size variations after hand-pressing and hand-mouthing activities

    EPA Science Inventory

    Hand-pressing trials and hand-to-mouth soil transfer experiments were conducted to better understand soil loadings, soil transfer ratios for three mouthing activities, and variations in particle size distributions under various conditions. Results indicated that sand caused highe...

  8. Improving Data Transfer Throughput with Direct Search Optimization

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

    Balaprakash, Prasanna; Morozov, Vitali; Kettimuthu, Rajkumar

    2016-01-01

    Improving data transfer throughput over high-speed long-distance networks has become increasingly difficult. Numerous factors such as nondeterministic congestion, dynamics of the transfer protocol, and multiuser and multitask source and destination endpoints, as well as interactions among these factors, contribute to this difficulty. A promising approach to improving throughput consists in using parallel streams at the application layer.We formulate and solve the problem of choosing the number of such streams from a mathematical optimization perspective. We propose the use of direct search methods, a class of easy-to-implement and light-weight mathematical optimization algorithms, to improve the performance of data transfers by dynamicallymore » adapting the number of parallel streams in a manner that does not require domain expertise, instrumentation, analytical models, or historic data. We apply our method to transfers performed with the GridFTP protocol, and illustrate the effectiveness of the proposed algorithm when used within Globus, a state-of-the-art data transfer tool, on productionWAN links and servers. We show that when compared to user default settings our direct search methods can achieve up to 10x performance improvement under certain conditions. We also show that our method can overcome performance degradation due to external compute and network load on source end points, a common scenario at high performance computing facilities.« less

  9. 40 CFR 63.2390 - What records must I keep?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Standards for Hazardous Air Pollutants: Organic Liquids Distribution (Non-Gasoline) Notifications, Reports... into which organic liquids are loaded at a transfer rack that is subject to control based on the... Method 27. (2) For transport vehicles without vapor collection equipment, current certification in...

  10. Electro-mechanical energy conversion system having a permanent magnet machine with stator, resonant transfer link and energy converter controls

    DOEpatents

    Skeist, S. Merrill; Baker, Richard H.

    2006-01-10

    An electro-mechanical energy conversion system coupled between an energy source and an energy load comprising an energy converter device including a permanent magnet induction machine coupled between the energy source and the energy load to convert the energy from the energy source and to transfer the converted energy to the energy load and an energy transfer multiplexer to control the flow of power or energy through the permanent magnetic induction machine.

  11. Biomechanical effect of latissimus dorsi tendon transfer for irreparable massive cuff tear.

    PubMed

    Oh, Joo Han; Tilan, Justin; Chen, Yu-Jen; Chung, Kyung Chil; McGarry, Michelle H; Lee, Thay Q

    2013-02-01

    The purpose of this study was to determine the biomechanical effects of latissimus dorsi transfer in a cadaveric model of massive posterosuperior rotator cuff tear. Eight cadaveric shoulders were tested at 0°, 30°, and 60° of abduction in the scapular plane with anatomically based muscle loading. Humeral rotational range of motion and the amount of humeral rotation due to muscle loading were measured. Glenohumeral kinematics and contact characteristics were measured throughout the range of motion. After testing in the intact condition, the supraspinatus and infraspinatus were resected. The cuff tear was then repaired by latissimus dorsi transfer. Two muscle loading conditions were applied after latissimus transfer to simulate increased tension that may occur due to limited muscle excursion. A repeated-measures analysis of variance was used for statistical analysis. The amount of internal rotation due to muscle loading and maximum internal rotation increased with massive cuff tear and was restored with latissimus transfer (P < .05). At maximum internal rotation, the humeral head apex shifted anteriorly, superiorly, and laterally at 0° of abduction after massive cuff tear (P < .05); this abnormal shift was corrected with latissimus transfer (P < .05). However, at 30° and 60° of abduction, latissimus transfer significantly altered kinematics (P < .05) and latissimus transfer with increased muscle loading increased contact pressure, especially at 60° of abduction. Latissimus dorsi transfer is beneficial in restoring humeral internal/external rotational range of motion, the internal/external rotational balance of the humerus, and glenohumeral kinematics at 0° of abduction. However, latissimus dorsi transfer with simulated limited excursion may lead to an overcompensation that can further deteriorate normal biomechanics, especially at higher abduction angles. Published by Mosby, Inc.

  12. Enhanced IMC design of load disturbance rejection for integrating and unstable processes with slow dynamics.

    PubMed

    Liu, Tao; Gao, Furong

    2011-04-01

    In view of the deficiencies in existing internal model control (IMC)-based methods for load disturbance rejection for integrating and unstable processes with slow dynamics, a modified IMC-based controller design is proposed to deal with step- or ramp-type load disturbance that is often encountered in engineering practices. By classifying the ways through which such load disturbance enters into the process, analytical controller formulae are correspondingly developed, based on a two-degree-of-freedom (2DOF) control structure that allows for separate optimization of load disturbance rejection from setpoint tracking. An obvious merit is that there is only a single adjustable parameter in the proposed controller, which in essence corresponds to the time constant of the closed-loop transfer function for load disturbance rejection, and can be monotonically tuned to meet a good trade-off between disturbance rejection performance and closed-loop robust stability. At the same time, robust tuning constraints are given to accommodate process uncertainties in practice. Illustrative examples from the recent literature are used to show effectiveness and merits of the proposed method for different cases of load disturbance. Copyright © 2010. Published by Elsevier Ltd.

  13. Numerical analysis of heat transfer in the exhaust gas flow in a diesel power generator

    NASA Astrophysics Data System (ADS)

    Brito, C. H. G.; Maia, C. B.; Sodré, J. R.

    2016-09-01

    This work presents a numerical study of heat transfer in the exhaust duct of a diesel power generator. The analysis was performed using two different approaches: the Finite Difference Method (FDM) and the Finite Volume Method (FVM), this last one by means of a commercial computer software, ANSYS CFX®. In FDM, the energy conservation equation was solved taking into account the estimated velocity profile for fully developed turbulent flow inside a tube and literature correlations for heat transfer. In FVM, the mass conservation, momentum, energy and transport equations were solved for turbulent quantities by the K-ω SST model. In both methods, variable properties were considered for the exhaust gas composed by six species: CO2, H2O, H2, O2, CO and N2. The entry conditions for the numerical simulations were given by experimental data available. The results were evaluated for the engine operating under loads of 0, 10, 20, and 37.5 kW. Test mesh and convergence were performed to determine the numerical error and uncertainty of the simulations. The results showed a trend of increasing temperature gradient with load increase. The general behaviour of the velocity and temperature profiles obtained by the numerical models were similar, with some divergence arising due to the assumptions made for the resolution of the models.

  14. Bridging the gap between peak and average loads on science networks

    DOE PAGES

    Nickolay, Sam; Jung, Eun -Sung; Kettimuthu, Rajkumar; ...

    2017-05-12

    Backbone networks are typically overprovisioned in order to support peak loads. Research and education networks (RENs), for example, are often designed to operate at 20–30% of capacity. Thus, Internet2 upgrades its backbone interconnects when the weekly 95th-percentile load is reliably above 30% of link capacity, and analysis of ESnet traffic between major laboratories shows a substantial gap between peak and average utilization. As science data volumes increase exponentially, it is unclear whether this overprovisioning trend can continue into the future. Even if overprovisioning is possible, it may not be the most cost-effective (and desirable) approach going forward. Under the currentmore » mode of free access to RENs, traffic at peak load may include both flows that need to be transferred in near-real time–for example, for computation and instrument monitoring and steering–and flows that are less time-critical, for example, archival and storage replication operations. Thus, peak load does not necessarily indicate the capacity that is absolutely required at that moment. We thus examine how data transfers are impacted when the average network load is increased while the network capacity is kept at the current levels. We also classify data transfers into on-demand (time-critical) and best-effort (less time-critical) and study the impact on both classes for different proportions of both the number of on-demand transfers and amount of bandwidth allocated for on-demand transfers. For our study, we use real transfer logs from production GridFTP servers to do simulation-based experiments as well as real experiments on a testbed. We find that when the transfer load is doubled and the network capacity is fixed at the current level, the gap between peak and average throughput decreases by an average of 18% in the simulation experiments and 16% in the testbed experiments, and the average slowdown experienced by the data transfers is under 1.5×. Moreover, when transfers are classified as on-demand or best-effort, on-demand transfers experience almost no slowdown and the mean slowdown experienced by best-effort transfers is under 2× in the simulation experiments and under 1.2× in the testbed experiments.« less

  15. Bridging the gap between peak and average loads on science networks

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

    Nickolay, Sam; Jung, Eun -Sung; Kettimuthu, Rajkumar

    Backbone networks are typically overprovisioned in order to support peak loads. Research and education networks (RENs), for example, are often designed to operate at 20–30% of capacity. Thus, Internet2 upgrades its backbone interconnects when the weekly 95th-percentile load is reliably above 30% of link capacity, and analysis of ESnet traffic between major laboratories shows a substantial gap between peak and average utilization. As science data volumes increase exponentially, it is unclear whether this overprovisioning trend can continue into the future. Even if overprovisioning is possible, it may not be the most cost-effective (and desirable) approach going forward. Under the currentmore » mode of free access to RENs, traffic at peak load may include both flows that need to be transferred in near-real time–for example, for computation and instrument monitoring and steering–and flows that are less time-critical, for example, archival and storage replication operations. Thus, peak load does not necessarily indicate the capacity that is absolutely required at that moment. We thus examine how data transfers are impacted when the average network load is increased while the network capacity is kept at the current levels. We also classify data transfers into on-demand (time-critical) and best-effort (less time-critical) and study the impact on both classes for different proportions of both the number of on-demand transfers and amount of bandwidth allocated for on-demand transfers. For our study, we use real transfer logs from production GridFTP servers to do simulation-based experiments as well as real experiments on a testbed. We find that when the transfer load is doubled and the network capacity is fixed at the current level, the gap between peak and average throughput decreases by an average of 18% in the simulation experiments and 16% in the testbed experiments, and the average slowdown experienced by the data transfers is under 1.5×. Moreover, when transfers are classified as on-demand or best-effort, on-demand transfers experience almost no slowdown and the mean slowdown experienced by best-effort transfers is under 2× in the simulation experiments and under 1.2× in the testbed experiments.« less

  16. Shear Load Transfer in High and Low Stress Tendons

    PubMed Central

    Kondratko-Mittnacht, Jaclyn; Duenwald-Kuehl, Sarah; Lakes, Roderic; Vanderby, Ray

    2016-01-01

    Background Tendon is an integral part of joint movement and stability, as it functions to transmit load from muscle to bone. It has an anisotropic, fibrous hierarchical structure that is generally loaded in the direction of its fibers/fascicles. Internal load distributions are altered when joint motion rotates an insertion site or when local damage disrupts fibers/fascicles, potentially causing inter-fiber (or inter-fascicular) shear. Tendons with different microstructure (helical versus linear) may redistribute loads differently. Method of Approach This study explored how shear redistributes axial loads in rat tail tendon (low stress tendons with linear microstructure) and porcine flexor tendon (high stress with helical microstructure) by creating lacerations on opposite sides of the tendon, ranging from about 20-60% of the tendon width, to create various magnitudes of shear. Differences in fascicular orientation were quantified using polarized light microscopy. Results and Conclusions Unexpectedly, both tendon types maintained about 20% of pre-laceration stress values after overlapping cuts of 60% of tendon width (no intact fibers end to end) suggesting that shear stress transfer can contribute more to overall tendon strength and stiffness than previously reported. All structural parameters for both tendon types decreased linearly with increasing laceration depth. The tail tendon had a more rapid decline in post-laceration elastic stress and modulus parameters as well as a more linear and less tightly packed fascicular structure, suggesting that positional tendons may be less well suited to redistribute loads via a shear mechanism. PMID:25700261

  17. Hip and knee net joint moments that correlate with success in lateral load transfers over a low friction surface.

    PubMed

    Catena, Robert D; Xu, Xu

    2016-12-01

    We previously described two different preferred strategies used to perform a lateral load transfer. The wide stance strategy was not used successfully on a low-friction surface, while the narrow stance strategy was successful. Here, we retrospectively examined lower extremity net joint moments between successful and unsuccessful strategies to determine if there is a kinetic benefit consideration that may go into choosing the preferred strategy. Success vs. failure over a novel slippery surface was used to dichotomise 35 healthy working-age individuals into the two groups (successful and unsuccessful). Participants performed lateral load transfers over three sequential surface conditions: high friction, novel low friction and practised low friction. The unsuccessful strategy required larger start torques, but lower dynamic moments during transfer compared to the successful strategy. These results indicate that the periodically unsuccessful strategy may be preferred because it requires less muscle recruitment and lower stresses on lower extremity soft tissues. Practitioner Summary: The reason for this paper is to retrospectively examine the joint moment in two different load transfer strategies that are used in a lateral load transfer. We found that periodically unsuccessful strategies that we previously reported may be a beneficial toward reduced lower extremity joint stresses.

  18. An In-Rush Current Suppression Technique for the Solid-State Transfer Switch System

    NASA Astrophysics Data System (ADS)

    Cheng, Po-Tai; Chen, Yu-Hsing

    More and more utility companies provide dual power feeders as a premier service of high power quality and reliability. To take advantage of this, the solid-state transfer switch (STS) is adopted to protect the sensitive load against the voltage sag. However, the fast transfer process may cause in-rush current on the load-side transformer due to the resulting DC-offset in its magnetic flux as the load-transfer is completed. The in-rush current can reach 2∼6 p.u. and it may trigger the over-current protections on the power feeder. This paper develops a flux estimation scheme and a thyristor gating scheme based on the impulse commutation bridge STS (ICBSTS) to minimize the DC-offset on the magnetic flux. By sensing the line voltages of both feeders, the flux estimator can predict the peak transient flux linkage at the moment of load-transfer and evaluate a suitable moment for the transfer to minimize the in-rush current. Laboratory test results are presented to validate the performance of the proposed system.

  19. Effect of Reynolds number, turbulence level and periodic wake flow on heat transfer on low pressure turbine blades.

    PubMed

    Suslov, D; Schulz, A; Wittig, S

    2001-05-01

    The development of effective cooling methods is of major importance for the design of new gas turbines blades. The conception of optimal cooling schemes requires a detailed knowledge of the heat transfer processes on the blade's surfaces. The thermal load of turbine blades is predominantly determined by convective heat transfer which is described by the local heat transfer coefficient. Heat transfer is closely related to the boundary layer development along the blade surface and hence depends on various flow conditions and geometrical parameters. Particularly Reynolds number, pressures gradient and turbulence level have great impact on the boundary layer development and the according heat transfer. Therefore, in the present study, the influence of Reynolds number, turbulence intensity, and periodic unsteady inflow on the local heat transfer of a typical low pressure turbine airfoil is experimentally examined in a plane cascade.

  20. In-line rotating torque sensor with on-board amplifier

    DOEpatents

    Kronberg, James W.

    1990-01-01

    A rotating torque sensor apparatus and method for measuring small torques comprising a shaft, a platform having a circuit board and a first moment arm attached to the shaft, a rotatable wheel coaxial with the shaft and having a second moment arm spaced apart from the first moment arm with a load cell therebetween for generating an electric signal as the torque is applied to the shaft and transferred through the moment arms to the load cell. The electrical signal is conducted from the load cell to the circuit board for filtering and amplification before being extracted from the torque assembly through a slip ring.

  1. Promotion effect of nickel loaded on CdS for photocatalytic H2 production in lactic acid solution

    NASA Astrophysics Data System (ADS)

    Chen, Shu; Chen, Xiaoping; Jiang, Qizhong; Yuan, Jian; Lin, Caifang; Shangguan, Wenfeng

    2014-10-01

    Low-cost Ni modified CdS was prepared via a hydrothermal reduction method. The hydrogen production activity of CdS loaded with 5 wt% Ni under visible light was even higher than that of the one loaded with 0.5 wt% Pt. The highest H2 evolution rate (3004.8 μmol h-1) occurred when the concentration of sacrificial agent (lactic acid) was 50 vol%. The nickel can quickly transfer excited electrons and enhance the photocatalytic H2 production activity. It was also found that the hydrogen evolution in this system was generated steadily from both water and lactic acid.

  2. The relationship between independent transfer skills and upper limb kinetics in wheelchair users.

    PubMed

    Tsai, Chung-Ying; Hogaboom, Nathan S; Boninger, Michael L; Koontz, Alicia M

    2014-01-01

    Transfers are one of the most physically demanding wheelchair activities. The purpose of this study was to determine if using proper transfer skills as measured by the Transfer Assessment Instrument (TAI) is associated with reduced loading on the upper extremities. Twenty-three wheelchair users performed transfers to a level-height bench while a series of forces plates, load cells, and a motion capture system recorded the biomechanics of their natural transferring techniques. Their transfer skills were simultaneously evaluated by two study clinicians using the TAI. Logistic regression and multiple linear regression models were used to determine the relationships between TAI scores and the kinetic variables on both arms across all joints. The results showed that the TAI measured transfer skills were closely associated with the magnitude and timing of joint moments (P < .02, model R(2) values ranged from 0.27 to 0.79). Proper completion of the skills which targeted the trailing arm was associated with lower average resultant moments and rates of rise of resultant moments at the trailing shoulder and/or elbow. Some skills involving the leading side had the effect of increasing the magnitude or rate loading on the leading side. Knowledge of the kinetic outcomes associated with each skill may help users to achieve the best load-relieving effects for their upper extremities.

  3. A pneumatic device for rapid loading of DNA sequencing gels.

    PubMed

    Panussis, D A; Cook, M W; Rifkin, L L; Snider, J E; Strong, J T; McGrane, R M; Wilson, R K; Mardis, E R

    1998-05-01

    This work describes the design and construction of a device that facilitates the loading of DNA samples onto polyacrylamide gels for detection in the Perkin Elmer/Applied Biosystems (PE/ABI) 373 and 377 DNA sequencing instruments. The device is mounted onto the existing gel cassettes and makes the process of loading high-density gels less cumbersome while the associated time and errors are reduced. The principle of operation includes the simultaneous transfer of the entire batch of samples, in which a spring-loaded air cylinder generates positive pressure and flexible silica capillaries transfer the samples. A retractable capillary array carrier allows the delivery ends of the capillaries to be held up clear of the gel during loader attachment on the gel plates, while enabling their insertion in the gel wells once the device is securely mounted. Gel-loading devices capable of simultaneously transferring 72 samples onto the PE/ABI 373 and 377 are currently being used in our production sequencing groups while a 96-sample transfer prototype undergoes testing.

  4. SLUDGE TREATMENT PROJECT COST COMPARISON BETWEEN HYDRAULIC LOADING AND SMALL CANISTER LOADING CONCEPTS

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

    GEUTHER J; CONRAD EA; RHOADARMER D

    2009-08-24

    The Sludge Treatment Project (STP) is considering two different concepts for the retrieval, loading, transport and interim storage of the K Basin sludge. The two design concepts under consideration are: (1) Hydraulic Loading Concept - In the hydraulic loading concept, the sludge is retrieved from the Engineered Containers directly into the Sludge Transport and Storage Container (STSC) while located in the STS cask in the modified KW Basin Annex. The sludge is loaded via a series of transfer, settle, decant, and filtration return steps until the STSC sludge transportation limits are met. The STSC is then transported to T Plantmore » and placed in storage arrays in the T Plant canyon cells for interim storage. (2) Small Canister Concept - In the small canister concept, the sludge is transferred from the Engineered Containers (ECs) into a settling vessel. After settling and decanting, the sludge is loaded underwater into small canisters. The small canisters are then transferred to the existing Fuel Transport System (FTS) where they are loaded underwater into the FTS Shielded Transfer Cask (STC). The STC is raised from the basin and placed into the Cask Transfer Overpack (CTO), loaded onto the trailer in the KW Basin Annex for transport to T Plant. At T Plant, the CTO is removed from the transport trailer and placed on the canyon deck. The CTO and STC are opened and the small canisters are removed using the canyon crane and placed into an STSC. The STSC is closed, and placed in storage arrays in the T Plant canyon cells for interim storage. The purpose of the cost estimate is to provide a comparison of the two concepts described.« less

  5. Design of Unstructured Adaptive (UA) NAS Parallel Benchmark Featuring Irregular, Dynamic Memory Accesses

    NASA Technical Reports Server (NTRS)

    Feng, Hui-Yu; VanderWijngaart, Rob; Biswas, Rupak; Biegel, Bryan (Technical Monitor)

    2001-01-01

    We describe the design of a new method for the measurement of the performance of modern computer systems when solving scientific problems featuring irregular, dynamic memory accesses. The method involves the solution of a stylized heat transfer problem on an unstructured, adaptive grid. A Spectral Element Method (SEM) with an adaptive, nonconforming mesh is selected to discretize the transport equation. The relatively high order of the SEM lowers the fraction of wall clock time spent on inter-processor communication, which eases the load balancing task and allows us to concentrate on the memory accesses. The benchmark is designed to be three-dimensional. Parallelization and load balance issues of a reference implementation will be described in detail in future reports.

  6. The modelling of the flow-induced vibrations of periodic flat and axial-symmetric structures with a wave-based method

    NASA Astrophysics Data System (ADS)

    Errico, F.; Ichchou, M.; De Rosa, S.; Bareille, O.; Franco, F.

    2018-06-01

    The stochastic response of periodic flat and axial-symmetric structures, subjected to random and spatially-correlated loads, is here analysed through an approach based on the combination of a wave finite element and a transfer matrix method. Although giving a lower computational cost, the present approach keeps the same accuracy of classic finite element methods. When dealing with homogeneous structures, the accuracy is also extended to higher frequencies, without increasing the time of calculation. Depending on the complexity of the structure and the frequency range, the computational cost can be reduced more than two orders of magnitude. The presented methodology is validated both for simple and complex structural shapes, under deterministic and random loads.

  7. ASSEMBLY TRANSFER SYSTEM DESCRIPTION DOCUMENT

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

    B. Gorpani

    2000-06-26

    The Assembly Transfer System (ATS) receives, cools, and opens rail and truck transportation casks from the Carrier/Cask Handling System (CCHS). The system unloads transportation casks consisting of bare Spent Nuclear Fuel (SNF) assemblies, single element canisters, and Dual Purpose Canisters (DPCs). For casks containing DPCs, the system opens the DPCs and unloads the SNF. The system stages the assemblies, transfer assemblies to and from fuel-blending inventory pools, loads them into Disposal Containers (DCs), temporarily seals and inerts the DC, decontaminates the DC and transfers it to the Disposal Container Handling System. The system also prepares empty casks and DPCs formore » off-site shipment. Two identical Assembly Transfer System lines are provided in the Waste Handling Building (WHB). Each line operates independently to handle the waste transfer throughput and to support maintenance operations. Each system line primarily consists of wet and dry handling areas. The wet handling area includes a cask transport system, cask and DPC preparation system, and a wet assembly handling system. The basket transport system forms the transition between the wet and dry handling areas. The dry handling area includes the dry assembly handling system, assembly drying system, DC preparation system, and DC transport system. Both the wet and dry handling areas are controlled by the control and tracking system. The system operating sequence begins with moving transportation casks to the cask preparation area. The cask preparation operations consist of cask cavity gas sampling, cask venting, cask cool-down, outer lid removal, and inner shield plug lifting fixture attachment. Casks containing bare SNF (no DPC) are filled with water and placed in the cask unloading pool. The inner shield plugs are removed underwater. For casks containing a DPC, the cask lid(s) is removed, and the DPC is penetrated, sampled, vented, and cooled. A DPC lifting fixture is attached and the cask is placed into the cask unloading pool. In the cask unloading pool the DPC is removed from the cask and placed in an overpack and the DPC lid is severed and removed. Assemblies are removed from either an open cask or DPC and loaded into assembly baskets positioned in the basket staging rack in the assembly unloading pool. A method called ''blending'' is utilized to load DCs with a heat output of less than 11.8 kW. This involves combining hotter and cooler assemblies from different baskets. Blending requires storing some of the hotter fuel assemblies in fuel-blending inventory pools until cooler assemblies are available. The assembly baskets are then transferred from the basket staging rack to the assembly handling cell and loaded into the assembly drying vessels. After drying, the assemblies are removed from the assembly drying vessels and loaded into a DC positioned below the DC load port. After installation of a DC inner lid and temporary sealing device, the DC is transferred to the DC decontamination cell where the top area of the DC, the DC lifting collar, and the DC inner lid and temporary sealing device are decontaminated, and the DC is evacuated and backfilled with inert gas to prevent prolonged clad exposure to air. The DC is then transferred to the Disposal Container Handling System for lid welding. In another cask preparation and decontamination area, lids are replaced on the empty transportation casks and DPC overpacks, the casks and DPC overpacks are decontaminated, inspected, and transferred to the Carrier/Cask Handling System for shipment off-site. All system equipment is designed to facilitate manual or remote operation, decontamination, and maintenance. The system interfaces with the Carrier/Cask Handling System for incoming and outgoing transportation casks and DPCs. The system also interfaces with the Disposal Container Handling System, which prepares the DC for loading and subsequently seals the loaded DC. The system support interfaces are the Waste Handling Building System and other internal WHB support systems.« less

  8. Cost Savings Associated with the Adoption of a Cloud Computing Data Transfer System for Trauma Patients.

    PubMed

    Feeney, James M; Montgomery, Stephanie C; Wolf, Laura; Jayaraman, Vijay; Twohig, Michael

    2016-09-01

    Among transferred trauma patients, challenges with the transfer of radiographic studies include problems loading or viewing the studies at the receiving hospitals, and problems manipulating, reconstructing, or evalu- ating the transferred images. Cloud-based image transfer systems may address some ofthese problems. We reviewed the charts of patients trans- ferred during one year surrounding the adoption of a cloud computing data transfer system. We compared the rates of repeat imaging before (precloud) and af- ter (postcloud) the adoption of the cloud-based data transfer system. During the precloud period, 28 out of 100 patients required 90 repeat studies. With the cloud computing transfer system in place, three out of 134 patients required seven repeat films. There was a statistically significant decrease in the proportion of patients requiring repeat films (28% to 2.2%, P < .0001). Based on an annualized volume of 200 trauma patient transfers, the cost savings estimated using three methods of cost analysis, is between $30,272 and $192,453.

  9. Two Dimensional Heat Transfer around Penetrations in Multilayer Insulation

    NASA Technical Reports Server (NTRS)

    Johnson, Wesley L.; Kelly, Andrew O.; Jumper, Kevin M.

    2012-01-01

    The objective of this task was to quantify thermal losses involving integrating MLI into real life situations. Testing specifically focused on the effects of penetrations (including structural attachments, electrical conduit/feedthroughs, and fluid lines) through MLI. While there have been attempts at quantifying these losses both analytically and experimentally, none have included a thorough investigation of the methods and materials that could be used in such applications. To attempt to quantify the excess heat load coming into the system due to the integration losses, a calorimeter was designed to study two dimensional heat transfer through penetrated MLI. The test matrix was designed to take as many variables into account as was possible with the limited test duration and system size. The parameters varied were the attachment mechanism, the buffer material (for buffer attachment mechanisms only), the thickness of the buffer, and the penetration material. The work done under this task is an attempt to measure the parasitic heat loads and affected insulation areas produced by system integration, to model the parasitic loads, and from the model produce engineering equations to allow for the determination of parasitic heat loads in future applications. The methods of integration investigated were no integration, using a buffer to thermally isolate the strut from the MLI, and temperature matching the MLI on the strut. Several materials were investigated as a buffer material including aerogel blankets, aerogel bead packages, cryolite, and even an evacuated vacuum space (in essence a no buffer condition).

  10. CANISTER TRANSFER SYSTEM DESCRIPTION DOCUMENT

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

    B. Gorpani

    2000-06-23

    The Canister Transfer System receives transportation casks containing large and small disposable canisters, unloads the canisters from the casks, stores the canisters as required, loads them into disposal containers (DCs), and prepares the empty casks for re-shipment. Cask unloading begins with cask inspection, sampling, and lid bolt removal operations. The cask lids are removed and the canisters are unloaded. Small canisters are loaded directly into a DC, or are stored until enough canisters are available to fill a DC. Large canisters are loaded directly into a DC. Transportation casks and related components are decontaminated as required, and empty casks aremore » prepared for re-shipment. One independent, remotely operated canister transfer line is provided in the Waste Handling Building System. The canister transfer line consists of a Cask Transport System, Cask Preparation System, Canister Handling System, Disposal Container Transport System, an off-normal canister handling cell with a transfer tunnel connecting the two cells, and Control and Tracking System. The Canister Transfer System operating sequence begins with moving transportation casks to the cask preparation area with the Cask Transport System. The Cask Preparation System prepares the cask for unloading and consists of cask preparation manipulator, cask inspection and sampling equipment, and decontamination equipment. The Canister Handling System unloads the canister(s) and places them into a DC. Handling equipment consists of a bridge crane hoist, DC loading manipulator, lifting fixtures, and small canister staging racks. Once the cask has been unloaded, the Cask Preparation System decontaminates the cask exterior and returns it to the Carrier/Cask Handling System via the Cask Transport System. After the DC is fully loaded, the Disposal Container Transport System moves the DC to the Disposal Container Handling System for welding. To handle off-normal canisters, a separate off-normal canister handling cell is located adjacent to the canister transfer cell and is interconnected to the transfer cell by means of the off-normal canister transfer tunnel. All canister transfer operations are controlled by the Control and Tracking System. The system interfaces with the Carrier/Cask Handling System for incoming and outgoing transportation casks. The system also interfaces with the Disposal Container Handling System, which prepares the DC for loading and subsequently seals the loaded DC. The system support interfaces are the Waste Handling Building System and other internal Waste Handling Building (WHB) support systems.« less

  11. External heat transfer predictions in a highly loaded transonic linear turbine guide vane cascade using an upwind biased Navier-Stokes solver

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

    Gehrer, A.; Jericha, H.

    External heat transfer predictions are performed for two-dimensional turbine blade cascades. The Reynolds-averaged Navier-Stokes equations with algebraic (Arnone and Pacciani, 1998), one-equation (Spalart and Allmaras, 1994), and two-equation (low-Re {kappa}-{epsilon}, Biswas and Fukuyama, 1994) turbulence closures are solved with a fully implicit time-marching finite volume method. Comparisons with measurements (Arts et al., 1990; Arts, 1994) for a highly loaded transonic turbine nozzle guide vane cascade show good agreement in some cases, but also reveal problems with transition prediction and turbulence modeling. Special attention has been focused on the low-Re {kappa}-{epsilon} model concerning the influence of the inlet boundary condition formore » the {epsilon}-equation and problems in the stagnation point region.« less

  12. Association of education and receiving social transfers with allostatic load in the Swiss population-based CoLaus study.

    PubMed

    Nicod, Edouard; Stringhini, Silvia; Marques-Vidal, Pedro; Paccaud, Fred; Waeber, Gérard; Lamiraud, Karine; Vollenweider, Peter; Bochud, Murielle

    2014-06-01

    Allostatic load reflects cumulative exposure to stressors throughout lifetime and has been associated with several adverse health outcomes. It is hypothesized that people with low socioeconomic status (SES) are exposed to higher chronic stress and have therefore greater levels of allostatic load. To assess the association of receiving social transfers and low education with allostatic load. We included 3589 participants (1812 women) aged over 35years and under retirement age from the population-based CoLaus study (Lausanne, Switzerland, 2003-2006). We computed an allostatic load index aggregating cardiovascular, metabolic, dyslipidemic and inflammatory markers. A novel index additionally including markers of oxidative stress was also examined. Men with low vs. high SES were more likely to have higher levels of allostatic load (odds ratio (OR)=1.93/2.34 for social transfers/education, 95%CI from 1.45 to 4.17). The same patterns were observed among women. Associations persisted after controlling for health behaviors and marital status. Low education and receiving social transfers independently and cumulatively predict high allostatic load and dysregulation of several homeostatic systems in a Swiss population-based study. Participants with low SES are at higher risk of oxidative stress, which may justify its inclusion as a separate component of allostatic load. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. ACHIEVING THE PROMISE OF THERAPEUTIC EXTRACELLULAR VESICLES: THE DEVIL IS IN DETAILS OF THERAPEUTIC LOADING

    PubMed Central

    Sutaria, Dhruvitkumar S.; Badawi, Mohamed; Phelps, Mitch A.; Schmittgen, Thomas D.

    2017-01-01

    Extracellular vesicles (EVs) represent a class of cell secreted organelles which naturally contain biomolecular cargo such as miRNA, mRNA and proteins. EVs mediate intercellular communication, enabling the transfer of functional nucleic acids from the cell of origin to the recipient cells. In addition, EVs make an attractive delivery vehicle for therapeutics owing to their increased stability in circulation, biocompatibility, low immunogenicity and toxicity profiles. EVs can also be engineered to display targeting moieties on their surfaces which enables targeting to desired tissues, organs or cells. While much has been learned on the role of EVs as cell communicators, the field of therapeutic EV application is currently under development. Critical to the future success of EV delivery system is the description of methods by which therapeutics can be successfully and efficiently loaded within the EVs. Two methods of loading of EVs with therapeutic cargo exist, endogenous and exogenous loading. We have therefore focused this review on describing the various published approaches for loading EVs with therapeutics. PMID:28315083

  14. Evaluating load transfer restoration, districts 1 and 3

    DOT National Transportation Integrated Search

    2002-07-01

    Since 1950, concrete pavements in California have been constructed without dowel bars in the transverse joints, Consequently, aggregate interlock has been the primary mechanism for load transfer across adjacent slabs. As the pavements age, the aggreg...

  15. Evaluation of load transfer devices : final report.

    DOT National Transportation Integrated Search

    1975-11-01

    This report describes the procedures and findings of a study conducted to evaluate two types of load transfer devices used in Louisiana--steel dowel bars and starlugs (a patented device). A statistical comparison was accomplished by evaluating existi...

  16. The Relationship between Independent Transfer Skills and Upper Limb Kinetics in Wheelchair Users

    PubMed Central

    Boninger, Michael L.; Koontz, Alicia M.

    2014-01-01

    Transfers are one of the most physically demanding wheelchair activities. The purpose of this study was to determine if using proper transfer skills as measured by the Transfer Assessment Instrument (TAI) is associated with reduced loading on the upper extremities. Twenty-three wheelchair users performed transfers to a level-height bench while a series of forces plates, load cells, and a motion capture system recorded the biomechanics of their natural transferring techniques. Their transfer skills were simultaneously evaluated by two study clinicians using the TAI. Logistic regression and multiple linear regression models were used to determine the relationships between TAI scores and the kinetic variables on both arms across all joints. The results showed that the TAI measured transfer skills were closely associated with the magnitude and timing of joint moments (P < .02, model R2 values ranged from 0.27 to 0.79). Proper completion of the skills which targeted the trailing arm was associated with lower average resultant moments and rates of rise of resultant moments at the trailing shoulder and/or elbow. Some skills involving the leading side had the effect of increasing the magnitude or rate loading on the leading side. Knowledge of the kinetic outcomes associated with each skill may help users to achieve the best load-relieving effects for their upper extremities. PMID:25162039

  17. Multiplexer/Demultiplexer Loading Tool (MDMLT)

    NASA Technical Reports Server (NTRS)

    Brewer, Lenox Allen; Hale, Elizabeth; Martella, Robert; Gyorfi, Ryan

    2012-01-01

    The purpose of the MDMLT is to improve the reliability and speed of loading multiplexers/demultiplexers (MDMs) in the Software Development and Integration Laboratory (SDIL) by automating the configuration management (CM) of the loads in the MDMs, automating the loading procedure, and providing the capability to load multiple or all MDMs concurrently. This loading may be accomplished in parallel, or single MDMs (remote). The MDMLT is a Web-based tool that is capable of loading the entire International Space Station (ISS) MDM configuration in parallel. It is able to load Flight Equivalent Units (FEUs), enhanced, standard, and prototype MDMs as well as both EEPROM (Electrically Erasable Programmable Read-Only Memory) and SSMMU (Solid State Mass Memory Unit) (MASS Memory). This software has extensive configuration management to track loading history, and the performance improvement means of loading the entire ISS MDM configuration of 49 MDMs in approximately 30 minutes, as opposed to 36 hours, which is what it took previously utilizing the flight method of S-Band uplink. The laptop version recently added to the MDMLT suite allows remote lab loading with the CM of information entered into a common database when it is reconnected to the network. This allows the program to reconfigure the test rigs quickly between shifts, allowing the lab to support a variety of onboard configurations during a single day, based on upcoming or current missions. The MDMLT Computer Software Configuration Item (CSCI) supports a Web-based command and control interface to the user. An interface to the SDIL File Transfer Protocol (FTP) server is supported to import Integrated Flight Loads (IFLs) and Internal Product Release Notes (IPRNs) into the database. An interface to the Monitor and Control System (MCS) is supported to control the power state, and to enable or disable the debug port of the MDMs to be loaded. Two direct interfaces to the MDM are supported: a serial interface (debug port) to receive MDM memory dump data and the calculated checksum, and the Small Computer System Interface (SCSI) to transfer load files to MDMs with hard disks. File transfer from the MDM Loading Tool to EEPROM within the MDM is performed via the MILSTD- 1553 bus, making use of the Real- Time Input/Output Processors (RTIOP) when using the rig-based MDMLT, and via a bus box when using the laptop MDMLT. The bus box is a cost-effective alternative to PC-1553 cards for the laptop. It is noted that this system can be modified and adapted to any avionic laboratory for spacecraft computer loading, ship avionics, or aircraft avionics where multiple configurations and strong configuration management of software/firmware loads are required.

  18. Modified Displacement Transfer Functions for Deformed Shape Predictions of Slender Curved Structures with Varying Curvatives

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Fleischer, Van Tran

    2014-01-01

    To eliminate the need to use finite-element modeling for structure shape predictions, a new method was invented. This method is to use the Displacement Transfer Functions to transform the measured surface strains into deflections for mapping out overall structural deformed shapes. The Displacement Transfer Functions are expressed in terms of rectilinearly distributed surface strains, and contain no material properties. This report is to apply the patented method to the shape predictions of non-symmetrically loaded slender curved structures with different curvatures up to a full circle. Because the measured surface strains are not available, finite-element analysis had to be used to analytically generate the surface strains. Previously formulated straight-beam Displacement Transfer Functions were modified by introducing the curvature-effect correction terms. Through single-point or dual-point collocations with finite-elementgenerated deflection curves, functional forms of the curvature-effect correction terms were empirically established. The resulting modified Displacement Transfer Functions can then provide quite accurate shape predictions. Also, the uniform straight-beam Displacement Transfer Function was applied to the shape predictions of a section-cut of a generic capsule (GC) outer curved sandwich wall. The resulting GC shape predictions are quite accurate in partial regions where the radius of curvature does not change sharply.

  19. Steam-load-forecasting technique for central-heating plants. Final report

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

    Lin, M.C.; Carnahan, J.V.

    Because boilers generally are most efficient at full loads, the Army could achieve significant savings by running fewer boilers at high loads rather than more boilers at low loads. A reliable load prediction technique could help ensure that only those boilers required to meet demand are on line. This report presents the results of an investigation into the feasibility of forecasting heat plant steam loads from historical patterns and weather information. Using steam flow data collected at Fort Benjamin Harrison, IN, a Box-Jenkins transfer function model with an acceptably small prediction error was initially identified. Initial investigation of forecast modelmore » development appeared successful. Dynamic regression methods using actual ambient temperatures yielded the best results. Box-Jenkins univariate models' results appeared slightly less accurate. Since temperature information was not needed for model building and forecasting, however, it is recommended that Box-Jenkins models be considered prime candidates for load forecasting due to their simpler mathematics.« less

  20. Guide to dowel load transfer systems for jointed concrete roadway pavements.

    DOT National Transportation Integrated Search

    2011-09-01

    This guide provides a summary of the factors and design theories that should be considered when designing : dowel load transfer systems for concrete pavement systems (including dowel basket design and fabrication) and : presents recommendations for w...

  1. A rationale method for evaluating unscrewing torque values of prosthetic screws in dental implants

    PubMed Central

    SALIBA, Felipe Miguel; CARDOSO, Mayra; TORRES, Marcelo Ferreira; TEIXEIRA, Alexandre Carvalho; LOURENÇO, Eduardo José Veras; TELLES, Daniel de Moraes

    2011-01-01

    Objectives Previous studies that evaluated the torque needed for removing dental implant screws have not considered the manner of transfer of the occlusal loads in clinical settings. Instead, the torque used for removal was applied directly to the screw, and most of them omitted the possibility that the hexagon could limit the action of the occlusal load in the loosening of the screws. The present study proposes a method for evaluating the screw removal torque in an anti-rotational device independent way, creating an unscrewing load transfer to the entire assembly, not only to the screw. Material and methods Twenty hexagonal abutments without the hexagon in their bases were fixed with a screw to 20 dental implants. They were divided into two groups: Group 1 used titanium screws and Group 2 used titanium screws covered with a solid lubricant. A torque of 32 Ncm was applied to the screw and then a custom-made wrench was used for rotating the abutment counterclockwise, to loosen the screw. A digital torque meter recorded the torque required to loosen the abutment. Results There was a significant difference between the means of Group 1 (38.62±6.43 Ncm) and Group 2 (48.47±5.04 Ncm), with p=0.001. Conclusion This methodology was effective in comparing unscrewing torque values of the implant-abutment junction even with a limited sample size. It confirmed a previously shown significant difference between two types of screws. PMID:21437472

  2. Wireless Power Transfer for Space Applications

    NASA Technical Reports Server (NTRS)

    Ramos, Gabriel Vazquez; Yuan, Jiann-Shiun

    2011-01-01

    This paper introduces an implementation for magnetic resonance wireless power transfer for space applications. The analysis includes an equivalent impedance study, loop material characterization, source/load resonance coupling technique, and system response behavior due to loads variability. System characterization is accomplished by executing circuit design from analytical equations and simulations using Matlab and SPICE. The theory was validated by a combination of different experiments that includes loop material consideration, resonance coupling circuits considerations, electric loads considerations and a small scale proof-of-concept prototype. Experiment results shows successful wireless power transfer for all the cases studied. The prototype provided about 4.5 W of power to the load at a separation of -5 cm from the source using a power amplifier rated for 7 W.

  3. Overview of aerothermodynamic loads definition study

    NASA Technical Reports Server (NTRS)

    Gaugler, Raymond E.

    1991-01-01

    The objective of the Aerothermodynamic Loads Definition Study is to develop methods of accurately predicting the operating environment in advanced Earth-to-Orbit (ETO) propulsion systems, such as the Space Shuttle Main Engine (SSME) powerhead. Development of time averaged and time dependent three dimensional viscous computer codes as well as experimental verification and engine diagnostic testing are considered to be essential in achieving that objective. Time-averaged, nonsteady, and transient operating loads must all be well defined in order to accurately predict powerhead life. Described here is work in unsteady heat flow analysis, improved modeling of preburner flow, turbulence modeling for turbomachinery, computation of three dimensional flow with heat transfer, and unsteady viscous multi-blade row turbine analysis.

  4. 24 CFR 3280.302 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... any device or other means designed to transfer home anchoring loads to the ground. Anchoring equipment... means a specific anchoring assembly device designed to transfer home anchoring loads to the ground... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Body and Frame Construction Requirements...

  5. Measurement of dowel bar response in rigid pavement

    DOT National Transportation Integrated Search

    1999-01-01

    The effectiveness of load transfer between adjacent slabs is an important component of long term rigid pavement performance. When load transfer is minimal or non-existent, concrete slabs must carry the full weight of truck axles across their entire l...

  6. Is tibialis anterior tendon transfer effective for recurrent clubfoot?

    PubMed

    Gray, Kelly; Burns, Joshua; Little, David; Bellemore, Michael; Gibbons, Paul

    2014-02-01

    Tibialis anterior tendon transfer surgery forms a part of Ponseti management for children with congenital talipes equinovarus who, after initial correction, present with residual dynamic supination. Although retrospective studies support good outcomes, prospective longitudinal studies in this population are lacking. We assessed strength, plantar loading, ROM, foot alignment, function, satisfaction, and quality of life in patients with clubfoot that recurred after Ponseti casting who met indications for tibialis anterior tendon transfer surgery, and compared them with a group of patients with clubfoot treated with casting but whose deformity did not recur (therefore who were not indicated for tibialis anterior tendon transfer surgery). Twenty children with idiopathic congenital talipes equinovarus indicated for tibialis anterior tendon transfer surgery were recruited. Assessment at baseline (before surgery), and 3, 6, and 12 months (after surgery) included strength (hand-held dynamometry), plantar loading (capacitance transducer matrix platform), ROM (Dimeglio scale), foot alignment (Foot Posture Index(©)), function and satisfaction (disease-specific instrument for clubfoot), and quality of life (Infant Toddler Quality of Life Questionnaire™). Outcomes were compared with those of 12 age-matched children with congenital talipes equinovarus not indicated for tibialis anterior tendon transfer surgery. Followup was 100% in the control group and 95% (19 of 20) in the tibialis anterior transfer group. At baseline, the tibialis anterior tendon transfer group had a significantly worse eversion-to-inversion strength ratio, plantar loading, ROM, foot alignment, and function and satisfaction. At 3 months after surgery, eversion-to-inversion strength, plantar loading, and function and satisfaction were no longer different between groups. Improvements were maintained at 12 months after surgery (eversion-to-inversion strength mean difference, 8% body weight; 95% CI, -26% to 11%; p = 0.412; plantar loading, p > 0.251; function and satisfaction, p = 0.076). ROM remained less and foot alignment more supinated in the tibialis anterior tendon transfer group between baseline and followup (p < 0.001, p < 0.001). Tibialis anterior tendon transfer surgery was an effective procedure, which at 12-month followup restored the balance of eversion-to-inversion strength and resulted in plantar loading and function and satisfaction outcomes similar to those of age-matched children with congenital talipes equinovarus who after Ponseti casting were not indicated for tibialis anterior tendon transfer.

  7. The generation of NGF-secreting primary rat monocytes: a comparison of different transfer methods.

    PubMed

    Hohsfield, Lindsay A; Geley, Stephan; Reindl, Markus; Humpel, Christian

    2013-05-31

    Nerve growth factor (NGF), a member of the neurotrophin family, is responsible for the maintenance and survival of cholinergic neurons in the basal forebrain. The degeneration of cholinergic neurons and reduced acetycholine levels are hallmarks of Alzheimer's disease (AD) as well as associated with learning and memory deficits. Thus far, NGF has proven the most potent neuroprotective molecule against cholinergic neurodegeneration. However, delivery of this factor into the brain remains difficult. Recent studies have begun to elucidate the potential use of monocytes as vehicles for therapeutic delivery into the brain. In this study, we employed different transfection and transduction methods to generate NGF-secreting primary rat monocytes. Specifically, we compared five methods for generating NGF-secreting monocytes: (1) cationic lipid-mediated transfection (Effectene and FuGene), (2) classical electroporation, (3) nucleofection, (4) protein delivery (Bioporter) and (5) lentiviral vectors. Here, we report that classical transfection methods (lipid-mediated transfection, electroporation, nucleofection) are inefficient tools for proper gene transfer into primary rat monocytes. We demonstrate that lentiviral infection and Bioporter can successfully transduce/load primary rat monocytes and produce effective NGF secretion. Furthermore, our results indicate that NGF is bioactive and that Bioporter-loaded monocytes do not appear to exhibit any functional disruptions (i.e. in their ability to differentiate and phagocytose beta-amyloid). Taken together, our results show that primary monocytes can be effectively loaded or transduced with NGF and provides information on the most effective method for generating NGF-secreting primary rat monocytes. This study also provides a basis for further development of primary monocytes as therapeutic delivery vehicles to the diseased AD brain. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Analysis of collapse in flattening a micro-grooved heat pipe by lateral compression

    NASA Astrophysics Data System (ADS)

    Li, Yong; He, Ting; Zeng, Zhixin

    2012-11-01

    The collapse of thin-walled micro-grooved heat pipes is a common phenomenon in the tube flattening process, which seriously influences the heat transfer performance and appearance of heat pipe. At present, there is no other better method to solve this problem. A new method by heating the heat pipe is proposed to eliminate the collapse during the flattening process. The effectiveness of the proposed method is investigated through a theoretical model, a finite element(FE) analysis, and experimental method. Firstly, A theoretical model based on a deformation model of six plastic hinges and the Antoine equation of the working fluid is established to analyze the collapse of thin walls at different temperatures. Then, the FE simulation and experiments of flattening process at different temperatures are carried out and compared with theoretical model. Finally, the FE model is followed to study the loads of the plates at different temperatures and heights of flattened heat pipes. The results of the theoretical model conform to those of the FE simulation and experiments in the flattened zone. The collapse occurs at room temperature. As the temperature increases, the collapse decreases and finally disappears at approximately 130 °C for various heights of flattened heat pipes. The loads of the moving plate increase as the temperature increases. Thus, the reasonable temperature for eliminating the collapse and reducing the load is approximately 130 °C. The advantage of the proposed method is that the collapse is reduced or eliminated by means of the thermal deformation characteristic of heat pipe itself instead of by external support. As a result, the heat transfer efficiency of heat pipe is raised.

  9. Multimode power processor

    DOEpatents

    O'Sullivan, G.A.; O'Sullivan, J.A.

    1999-07-27

    In one embodiment, a power processor which operates in three modes: an inverter mode wherein power is delivered from a battery to an AC power grid or load; a battery charger mode wherein the battery is charged by a generator; and a parallel mode wherein the generator supplies power to the AC power grid or load in parallel with the battery. In the parallel mode, the system adapts to arbitrary non-linear loads. The power processor may operate on a per-phase basis wherein the load may be synthetically transferred from one phase to another by way of a bumpless transfer which causes no interruption of power to the load when transferring energy sources. Voltage transients and frequency transients delivered to the load when switching between the generator and battery sources are minimized, thereby providing an uninterruptible power supply. The power processor may be used as part of a hybrid electrical power source system which may contain, in one embodiment, a photovoltaic array, diesel engine, and battery power sources. 31 figs.

  10. Multimode power processor

    DOEpatents

    O'Sullivan, George A.; O'Sullivan, Joseph A.

    1999-01-01

    In one embodiment, a power processor which operates in three modes: an inverter mode wherein power is delivered from a battery to an AC power grid or load; a battery charger mode wherein the battery is charged by a generator; and a parallel mode wherein the generator supplies power to the AC power grid or load in parallel with the battery. In the parallel mode, the system adapts to arbitrary non-linear loads. The power processor may operate on a per-phase basis wherein the load may be synthetically transferred from one phase to another by way of a bumpless transfer which causes no interruption of power to the load when transferring energy sources. Voltage transients and frequency transients delivered to the load when switching between the generator and battery sources are minimized, thereby providing an uninterruptible power supply. The power processor may be used as part of a hybrid electrical power source system which may contain, in one embodiment, a photovoltaic array, diesel engine, and battery power sources.

  11. Dynamic Stiffness Transfer Function of an Electromechanical Actuator Using System Identification

    NASA Astrophysics Data System (ADS)

    Kim, Sang Hwa; Tahk, Min-Jea

    2018-04-01

    In the aeroelastic analysis of flight vehicles with electromechanical actuators (EMAs), an accurate prediction of flutter requires dynamic stiffness characteristics of the EMA. The dynamic stiffness transfer function of the EMA with brushless direct current (BLDC) motor can be obtained by conducting complicated mathematical calculations of control algorithms and mechanical/electrical nonlinearities using linearization techniques. Thus, system identification approaches using experimental data, as an alternative, have considerable advantages. However, the test setup for system identification is expensive and complex, and experimental procedures for data collection are time-consuming tasks. To obtain the dynamic stiffness transfer function, this paper proposes a linear system identification method that uses information obtained from a reliable dynamic stiffness model with a control algorithm and nonlinearities. The results of this study show that the system identification procedure is compact, and the transfer function is able to describe the dynamic stiffness characteristics of the EMA. In addition, to verify the validity of the system identification method, the simulation results of the dynamic stiffness transfer function and the dynamic stiffness model were compared with the experimental data for various external loads.

  12. Analysis of transient, linear wave propagation in shells by the finite difference method

    NASA Technical Reports Server (NTRS)

    Geers, T. L.; Sobel, L. H.

    1971-01-01

    The applicability of the finite difference method to propagation problems in shells, and the response of a cylindrical shell with cutouts to both longitudinal and radial transient excitations are investigated. It is found that the only inherent limitation of the finite difference method is its inability to reproduce accurately response discontinuities. The short wave length limitations of thin shell theory create significant convergence difficulties may often be overcome through proper selection of finite difference mesh dimensions and temporal or spatial smoothing of the excitation. Cutouts produce moderate changes in early and intermediate time response of a cylindrical shell to axisymmetric pulse loads applied at one end. The cutouts may facilitate the undesirable late-time transfer of load-injected extensional energy into nonaxisymmetric flexural response.

  13. Fluidized bed and method and system for gas component capture

    DOEpatents

    Krutka, Holly; Wilson, Cody; Starns, Travis

    2016-05-31

    The present disclosure is directed to a process that allows dry sorbents to remove a target constituent, such as carbon dioxide (CO.sub.2), from a gas stream. A staged fluidized bed separator enables gas and sorbent to move in opposite directions. The sorbent is loaded with target constituent in the separator. It is then transferred to a regenerator where the target constituent is stripped. The temperature of the separator and regenerator are controlled. After it is removed from the regenerator, the sorbent is then transferred back to the separator.

  14. Turbine blade unsteady aerodynamic loading and heat transfer

    NASA Astrophysics Data System (ADS)

    Johnston, David Alan

    Stator indexing to minimize the unsteady aerodynamic loading of closely spaced airfoil rows in turbomachinery is a new technique for the passive control of flow-induced vibrations. This technique, along with the effects of steady blade loading, were studied by means of experiments performed in a two-stage low-speed research turbine. With the second vane row fixed, the inlet vane row was indexed to six positions over one vane-pitch cycle for a range of stage loadings. The aerodynamic forcing function to the first-stage rotor was measured in the rotating reference frame, with the resulting rotor blade unsteady aerodynamic response quantified by rotor blades instrumented with dynamic pressure transducers. Reductions in the unsteady lift magnitude were achieved at all turbine operating conditions, with attenuation ranging from 37% to 74% of the maximum unsteady lift. Additionally, in complementary experiments, the effects of stator indexing and steady blade loading on the unsteady heat transfer of the first- and second-stage rotors was studied for the design and highest blade loading conditions using platinum-film heat gages. The attenuation of unsteady heat transfer coefficient was blade-loading dependent and location dependent along the chord and span, ranging 10% to 90% of maximum. Due to the high degree of location dependence of attenuation, stator indexing is therefore best suited to minimize unsteady heat transfer in local hot spots of the blade rather than the blade as a whole.

  15. Photoluminescence of cerium fluoride and cerium-doped lanthanum fluoride nanoparticles and investigation of energy transfer to photosensitizer molecules.

    PubMed

    Cooper, Daniel R; Kudinov, Konstantin; Tyagi, Pooja; Hill, Colin K; Bradforth, Stephen E; Nadeau, Jay L

    2014-06-28

    CexLa1-xF3 nanoparticles have been proposed for use in nanoscintillator-photosensitizer systems, where excitation of nanoparticles by ionizing radiation would result in energy transfer to photosensitizer molecules, effectively combining the effects of radiotherapy and photodynamic therapy. Thus far, there have been few experimental investigations of such systems. This study reports novel synthesis methods for water-dispersible Ce0.1La0.9F3/LaF3 and CeF3/LaF3 core/shell nanoparticles and an investigation of energy transfer to photosensitizers. Unbound deuteroporphyrin IX 2,4-disulfonic acid was found to substantially quench the luminescence of large (>10 nm diameter) aminocaproic acid-stabilized nanoparticles at reasonable concentrations and loading amounts: up to 80% quenching at 6% w/w photosensitizer loading. Energy transfer was found to occur primarily through a cascade, with excitation of "regular" site Ce(3+) at 252 nm relayed to photosensitizer molecules at the nanoparticle surface through intermediate "perturbed" Ce(3+) sites. Smaller (<5 nm) citrate-stabilized nanoparticles were coated with the bisphosphonate alendronate, allowing covalent conjugation to chlorin e6 and resulting in static quenching of the nanoparticle luminescence: ∼50% at ∼0.44% w/w. These results provide insight into energy transfer mechanisms that may prove valuable for optimizing similar systems.

  16. A data-driven approach of load monitoring on laminated composite plates using support vector machine

    NASA Astrophysics Data System (ADS)

    Gwon, Y. S.; Fekrmandi, H.

    2018-03-01

    In this study, the surface response to excitation method (SuRE) is investigated using a data-driven method for load monitoring on a laminated composite plate structure. The SuRE method is an emerging approach in ultrasonic wavebased structural health monitoring (SHM) field. In this method, a range of high-frequency, surface-guided waves are excited on the structure using piezoceramic elements. The waves propagate on the structure and interact with internal or surface damages. Initially, a baseline data of the intact structure is created by measuring the frequency transfer function between the excitation and sensing point. The integrity of structure is evaluated by monitoring changes in the frequency spectrums. The SuRE method has effectively been used for a variety of SHM applications including the detection of loose bolts, delamination in composite structures, internal corrosion in pipelines, and load and impact monitoring. Data obtained using the SuRE method was used for identifying the location of the applied load on a laminated composite plate using Support Vector Machine (SVM). A set of two piezoelectric elements were attached on the surface of the plate. A sweep excitation (150-250 kHz) generated surface-guided waves, and the transmitted waves were monitored at the sensory positions. The reference data set was measured simultaneously from the sensors. The plate was subjected to static loads while health monitoring data was being captured using the SuRE method. The confusion matrix indicated that the model classified correctly with up to 99.8% accuracy.

  17. Method for exciting inductive-resistive loads with high and controllable direct current

    DOEpatents

    Hill, Jr., Homer M.

    1976-01-01

    Apparatus and method for transmitting dc power to a load circuit by applying a dc voltage from a standard waveform synthesizer to duration modulate a bipolar rectangular wave generator. As the amplitude of the dc voltage increases, the widths of the rectangular wave generator output pulses increase, and as the amplitude of the dc voltage decreases, the widths of the rectangular wave generator output pulses decrease. Thus, the waveform synthesizer selectively changes the durations of the rectangular wave generator bipolar output pulses so as to produce a rectangular wave ac carrier that is duration modulated in accordance with and in direct proportion to the voltage amplitude from the synthesizer. Thereupon, by transferring the carrier to the load circuit through an amplifier and a rectifier, the load current also corresponds directly to the voltage amplitude from the synthesizer. To this end, the rectified wave at less than 100% duty factor, amounts to a doubled frequency direct voltage pulse train for applying a direct current to the load, while the current ripple is minimized by a high L/R in the load circuit. In one embodiment, a power transmitting power amplifier means having a dc power supply is matched to the load circuit through a transformer for current magnification without sacrificing load current duration capability, while negative voltage and current feedback are provided in order to insure good output fidelity.

  18. The transfer function method for gear system dynamics applied to conventional and minimum excitation gearing designs

    NASA Technical Reports Server (NTRS)

    Mark, W. D.

    1982-01-01

    A transfer function method for predicting the dynamic responses of gear systems with more than one gear mesh is developed and applied to the NASA Lewis four-square gear fatigue test apparatus. Methods for computing bearing-support force spectra and temporal histories of the total force transmitted by a gear mesh, the force transmitted by a single pair of teeth, and the maximum root stress in a single tooth are developed. Dynamic effects arising from other gear meshes in the system are included. A profile modification design method to minimize the vibration excitation arising from a pair of meshing gears is reviewed and extended. Families of tooth loading functions required for such designs are developed and examined for potential excitation of individual tooth vibrations. The profile modification design method is applied to a pair of test gears.

  19. The more total cognitive load is reduced by cues, the better retention and transfer of multimedia learning: A meta-analysis and two meta-regression analyses.

    PubMed

    Xie, Heping; Wang, Fuxing; Hao, Yanbin; Chen, Jiaxue; An, Jing; Wang, Yuxin; Liu, Huashan

    2017-01-01

    Cueing facilitates retention and transfer of multimedia learning. From the perspective of cognitive load theory (CLT), cueing has a positive effect on learning outcomes because of the reduction in total cognitive load and avoidance of cognitive overload. However, this has not been systematically evaluated. Moreover, what remains ambiguous is the direct relationship between the cue-related cognitive load and learning outcomes. A meta-analysis and two subsequent meta-regression analyses were conducted to explore these issues. Subjective total cognitive load (SCL) and scores on a retention test and transfer test were selected as dependent variables. Through a systematic literature search, 32 eligible articles encompassing 3,597 participants were included in the SCL-related meta-analysis. Among them, 25 articles containing 2,910 participants were included in the retention-related meta-analysis and the following retention-related meta-regression, while there were 29 articles containing 3,204 participants included in the transfer-related meta-analysis and the transfer-related meta-regression. The meta-analysis revealed a statistically significant cueing effect on subjective ratings of cognitive load (d = -0.11, 95% CI = [-0.19, -0.02], p < 0.05), retention performance (d = 0.27, 95% CI = [0.08, 0.46], p < 0.01), and transfer performance (d = 0.34, 95% CI = [0.12, 0.56], p < 0.01). The subsequent meta-regression analyses showed that dSCL for cueing significantly predicted dretention for cueing (β = -0.70, 95% CI = [-1.02, -0.38], p < 0.001), as well as dtransfer for cueing (β = -0.60, 95% CI = [-0.92, -0.28], p < 0.001). Thus in line with CLT, adding cues in multimedia materials can indeed reduce SCL and promote learning outcomes, and the more SCL is reduced by cues, the better retention and transfer of multimedia learning.

  20. The more total cognitive load is reduced by cues, the better retention and transfer of multimedia learning: A meta-analysis and two meta-regression analyses

    PubMed Central

    Hao, Yanbin; Chen, Jiaxue; An, Jing; Wang, Yuxin; Liu, Huashan

    2017-01-01

    Cueing facilitates retention and transfer of multimedia learning. From the perspective of cognitive load theory (CLT), cueing has a positive effect on learning outcomes because of the reduction in total cognitive load and avoidance of cognitive overload. However, this has not been systematically evaluated. Moreover, what remains ambiguous is the direct relationship between the cue-related cognitive load and learning outcomes. A meta-analysis and two subsequent meta-regression analyses were conducted to explore these issues. Subjective total cognitive load (SCL) and scores on a retention test and transfer test were selected as dependent variables. Through a systematic literature search, 32 eligible articles encompassing 3,597 participants were included in the SCL-related meta-analysis. Among them, 25 articles containing 2,910 participants were included in the retention-related meta-analysis and the following retention-related meta-regression, while there were 29 articles containing 3,204 participants included in the transfer-related meta-analysis and the transfer-related meta-regression. The meta-analysis revealed a statistically significant cueing effect on subjective ratings of cognitive load (d = −0.11, 95% CI = [−0.19, −0.02], p < 0.05), retention performance (d = 0.27, 95% CI = [0.08, 0.46], p < 0.01), and transfer performance (d = 0.34, 95% CI = [0.12, 0.56], p < 0.01). The subsequent meta-regression analyses showed that dSCL for cueing significantly predicted dretention for cueing (β = −0.70, 95% CI = [−1.02, −0.38], p < 0.001), as well as dtransfer for cueing (β = −0.60, 95% CI = [−0.92, −0.28], p < 0.001). Thus in line with CLT, adding cues in multimedia materials can indeed reduce SCL and promote learning outcomes, and the more SCL is reduced by cues, the better retention and transfer of multimedia learning. PMID:28854205

  1. Dynamic analysis of elastic rubber tired car wheel breaking under variable normal load

    NASA Astrophysics Data System (ADS)

    Fedotov, A. I.; Zedgenizov, V. G.; Ovchinnikova, N. I.

    2017-10-01

    The purpose of the paper is to analyze the dynamics of the braking of the wheel under normal load variations. The paper uses a mathematical simulation method according to which the calculation model of an object as a mechanical system is associated with a dynamically equivalent schematic structure of the automatic control. Transfer function tool analyzing structural and technical characteristics of an object as well as force disturbances were used. It was proved that the analysis of dynamic characteristics of the wheel subjected to external force disturbances has to take into account amplitude and phase-frequency characteristics. Normal load variations impact car wheel braking subjected to disturbances. The closer slip to the critical point is, the higher the impact is. In the super-critical area, load variations cause fast wheel blocking.

  2. Margin and sensitivity methods for security analysis of electric power systems

    NASA Astrophysics Data System (ADS)

    Greene, Scott L.

    Reliable operation of large scale electric power networks requires that system voltages and currents stay within design limits. Operation beyond those limits can lead to equipment failures and blackouts. Security margins measure the amount by which system loads or power transfers can change before a security violation, such as an overloaded transmission line, is encountered. This thesis shows how to efficiently compute security margins defined by limiting events and instabilities, and the sensitivity of those margins with respect to assumptions, system parameters, operating policy, and transactions. Security margins to voltage collapse blackouts, oscillatory instability, generator limits, voltage constraints and line overloads are considered. The usefulness of computing the sensitivities of these margins with respect to interarea transfers, loading parameters, generator dispatch, transmission line parameters, and VAR support is established for networks as large as 1500 buses. The sensitivity formulas presented apply to a range of power system models. Conventional sensitivity formulas such as line distribution factors, outage distribution factors, participation factors and penalty factors are shown to be special cases of the general sensitivity formulas derived in this thesis. The sensitivity formulas readily accommodate sparse matrix techniques. Margin sensitivity methods are shown to work effectively for avoiding voltage collapse blackouts caused by either saddle node bifurcation of equilibria or immediate instability due to generator reactive power limits. Extremely fast contingency analysis for voltage collapse can be implemented with margin sensitivity based rankings. Interarea transfer can be limited by voltage limits, line limits, or voltage stability. The sensitivity formulas presented in this thesis apply to security margins defined by any limit criteria. A method to compute transfer margins by directly locating intermediate events reduces the total number of loadflow iterations required by each margin computation and provides sensitivity information at minimal additional cost. Estimates of the effect of simultaneous transfers on the transfer margins agree well with the exact computations for a network model derived from a portion of the U.S grid. The accuracy of the estimates over a useful range of conditions and the ease of obtaining the estimates suggest that the sensitivity computations will be of practical value.

  3. Efficient transformer for electromagnetic waves

    DOEpatents

    Miller, R.B.

    A transformer structure for efficient transfer of electromagnetic energy from a transmission line to an unmatched load provides voltage multiplication and current division by a predetermined constant. Impedance levels are transformed by the square of that constant. The structure includes a wave splitter, connected to an input transmission device and to a plurality of output transmission devices. The output transmission devices are effectively connected in parallel to the input transmission device. The output transmission devices are effectively series connected to provide energy to a load. The transformer structure is particularly effective in increasing efficiency of energy transfer through an inverting convolute structure by capturing and transferring energy losses from the inverter to the load.

  4. Resource loading system and method for use in atmosphere-containment scenarios

    DOEpatents

    Dilday, Jr., Daniel R.; Reyes, Roberto; Weidmeyer, Stanley

    2017-09-12

    The invention provides a system for preventing fluid exchange between the interior and exterior of containment enclosures such as process-, hazard-, and research-enclosure systems generally, gloveboxes, containment systems, isolation systems, confinement systems, cleanrooms, negative air systems, and positive air system areas while simultaneously providing material transfer into and out of the enclosures. The invention also provides a method for transporting material into or out of a containment structure.

  5. Use of CAD Geometry in MDO

    NASA Technical Reports Server (NTRS)

    Samareh, Jamshid A.

    1996-01-01

    The purpose of this paper is to discuss the use of Computer-Aided Design (CAD) geometry in a Multi-Disciplinary Design Optimization (MDO) environment. Two techniques are presented to facilitate the use of CAD geometry by different disciplines, such as Computational Fluid Dynamics (CFD) and Computational Structural Mechanics (CSM). One method is to transfer the load from a CFD grid to a CSM grid. The second method is to update the CAD geometry for CSM deflection.

  6. Evaluation of torsional load transfer for drilled shaft foundations : final report : SPR 304-701.

    DOT National Transportation Integrated Search

    2016-05-01

    Despite the prevalence of the use of drilled shafts for the support of traffic signal and signs along : state highways, relatively little is known about the torsional load transfer between the structure and soil providing : its support. A review of l...

  7. 46 CFR 112.30-5 - Transfer of emergency loads.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having an Automatically Connected Storage Battery as the Sole Emergency Power Source § 112.30-5 Transfer of emergency loads. If there is a reduction of potential of the...

  8. 46 CFR 112.25-10 - Transfer of emergency loads.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having an Automatic Starting Diesel Engine or Gas Turbine Driven Emergency Power Source as the Sole Emergency Power Source § 112.25-10 Transfer of emergency loads. (a) When...

  9. 46 CFR 112.25-10 - Transfer of emergency loads.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having an Automatic Starting Diesel Engine or Gas Turbine Driven Emergency Power Source as the Sole Emergency Power Source § 112.25-10 Transfer of emergency loads. (a) When...

  10. 46 CFR 112.30-5 - Transfer of emergency loads.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having an Automatically Connected Storage Battery as the Sole Emergency Power Source § 112.30-5 Transfer of emergency loads. If there is a reduction of potential of the...

  11. 46 CFR 112.25-10 - Transfer of emergency loads.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having an Automatic Starting Diesel Engine or Gas Turbine Driven Emergency Power Source as the Sole Emergency Power Source § 112.25-10 Transfer of emergency loads. (a) When...

  12. 46 CFR 112.25-10 - Transfer of emergency loads.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having an Automatic Starting Diesel Engine or Gas Turbine Driven Emergency Power Source as the Sole Emergency Power Source § 112.25-10 Transfer of emergency loads. (a) When...

  13. 46 CFR 112.30-5 - Transfer of emergency loads.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having an Automatically Connected Storage Battery as the Sole Emergency Power Source § 112.30-5 Transfer of emergency loads. If there is a reduction of potential of the...

  14. 46 CFR 112.30-5 - Transfer of emergency loads.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having an Automatically Connected Storage Battery as the Sole Emergency Power Source § 112.30-5 Transfer of emergency loads. If there is a reduction of potential of the...

  15. 46 CFR 112.25-10 - Transfer of emergency loads.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having an Automatic Starting Diesel Engine or Gas Turbine Driven Emergency Power Source as the Sole Emergency Power Source § 112.25-10 Transfer of emergency loads. (a) When...

  16. 46 CFR 112.30-5 - Transfer of emergency loads.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having an Automatically Connected Storage Battery as the Sole Emergency Power Source § 112.30-5 Transfer of emergency loads. If there is a reduction of potential of the...

  17. Doubly fed induction machine

    DOEpatents

    Skeist, S. Merrill; Baker, Richard H.

    2005-10-11

    An electro-mechanical energy conversion system coupled between an energy source and an energy load including an energy converter device having a doubly fed induction machine coupled between the energy source and the energy load to convert the energy from the energy source and to transfer the converted energy to the energy load and an energy transfer multiplexer coupled to the energy converter device to control the flow of power or energy through the doubly fed induction machine.

  18. Schinus terebinthifolius countercurrent chromatography (Part III): Method transfer from small countercurrent chromatography column to preparative centrifugal partition chromatography ones as a part of method development.

    PubMed

    das Neves Costa, Fernanda; Hubert, Jane; Borie, Nicolas; Kotland, Alexis; Hewitson, Peter; Ignatova, Svetlana; Renault, Jean-Hugues

    2017-03-03

    Countercurrent chromatography (CCC) and centrifugal partition chromatography (CPC) are support free liquid-liquid chromatography techniques sharing the same basic principles and features. Method transfer has previously been demonstrated for both techniques but never from one to another. This study aimed to show such a feasibility using fractionation of Schinus terebinthifolius berries dichloromethane extract as a case study. Heptane - ethyl acetate - methanol -water (6:1:6:1, v/v/v/v) was used as solvent system with masticadienonic and 3β-masticadienolic acids as target compounds. The optimized separation methodology previously described in Part I and II, was scaled up from an analytical hydrodynamic CCC column (17.4mL) to preparative hydrostatic CPC instruments (250mL and 303mL) as a part of method development. Flow-rate and sample loading were further optimized on CPC. Mobile phase linear velocity is suggested as a transfer invariant parameter if the CPC column contains sufficient number of partition cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Plasmon-enhanced photocatalytic activity of Na0.9Mg0.45Ti3.55O8 loaded with noble metals directly observed with scanning Kelvin probe microscopy.

    PubMed

    Wang, Jing-Zhou; Guo, Ze-Qing; Zhou, Jian-Ping; Lei, Yu-Xi

    2018-07-27

    The noble metals Au, Ag and Pt were loaded onto Na 0.9 Mg 0.45 Ti 3.55 O 8 (NMTO) using a chemical bath deposition method devised in our recent work for the first time. The composite photocatalysts exhibit more effective photodegradation of methylene blue, due to the Schottky barrier built between NMTO and noble metal. Hot electrons generated during localized surface plasmon processes in metal nanoparticles transfer to the semiconductor, manifesting as a depression of surface potential directly detectable by scanning Kelvin probe microscopy. The key factor responsible for the improved ability of semiconductor-based photocatalysts is charge separation. The most effective weight concentrations of Au, Ag and Pt loaded onto NMTO were found to be 5.00%, 12.6% and 5.55% respectively. NMTO loaded with noble metals shows good photostability and recyclability for the degradation of methylene blue. A possible mechanism for the photodegradation of methylene blue over NMTO loaded with noble metals is proposed. This work highlights the potential application of NMTO-based photocatalysts, and provides an effective method to detect localized surface plasmons.

  20. Biomechanical Analysis of Suture Anchor vs Tenodesis Screw for FHL Transfer.

    PubMed

    Drakos, Mark C; Gott, Michael; Karnovsky, Sydney C; Murphy, Conor I; DeSandis, Bridget A; Chinitz, Noah; Grande, Daniel; Chahine, Nadeen

    2017-07-01

    Chronic Achilles injury is often treated with flexor hallucis longus (FHL) tendon transfer to the calcaneus using 1 or 2 incisions. A single incision avoids the risks of extended dissections yet yields smaller grafts, which may limit fixation options. We investigated the required length of FHL autograft and biomechanical profiles for suture anchor and biotenodesis screw fixation. Single-incision FHL transfer with suture anchor or biotenodesis screw fixation to the calcaneus was performed on 20 fresh cadaveric specimens. Specimens were cyclically loaded until maximal load to failure. Length of FHL tendon harvest, ultimate load, stiffness, and mode of failure were recorded. Tendon harvest length needed for suture anchor fixation was 16.8 ± 2.1 mm vs 29.6 ± 2.4 mm for biotenodesis screw ( P = .002). Ultimate load to failure was not significantly different between groups. A significant inverse correlation existed between failure load and donor age when all specimens were pooled (ρ = -0.49, P < .05). Screws in younger specimens (fewer than 70) resulted in significantly greater failure loads ( P < .03). No difference in stiffness was found between groups. Modes of failure for screw fixation were either tunnel pullout (n = 6) or tendon rupture (n = 4). Anchor failure occurred mostly by suture breakage (n = 8). Adequate FHL tendon length could be harvested through a single posterior incision for fixation to the calcaneus with either fixation option, but suture anchor required significantly less graft length. Stiffness, fixation strength, and load to failure were comparable between groups. An inverse correlation existed between failure load and donor age. Younger specimens with screw fixation demonstrated significantly greater failure loads. Adequate harvest length for FHL transfer could be achieved with a single posterior incision. There was no difference in strength of fixation between suture anchor and biotenodesis screw.

  1. Development Of Metallic Thermal Protection System For The Expert Re-Entry Vehicle: Design Verification

    NASA Astrophysics Data System (ADS)

    Fatemi, Javad

    2011-05-01

    The thermal protection system of the EXPERT re-entry vehicle is subjected to accelerations, vibrations, acoustic and shock loads during launch and aero-heating loads and aerodynamic forces during re-entry. To fully understand the structural and thermomechanical performances of the TPS, heat transfer analysis, thermal stress analysis, and thermal buckling analysis must be performed. This requires complex three-dimensional thermal and structural models of the entire TPS including the insulation and sensors. Finite element (FE) methods are employed to assess the thermal and structural response of the TPS to the mechanical and aerothermal loads. The FE analyses results are used for the design verification and design improvement of the EXPERT thermal protection system.

  2. Dynamic Transfers Of Tasks Among Computers

    NASA Technical Reports Server (NTRS)

    Liu, Howard T.; Silvester, John A.

    1989-01-01

    Allocation scheme gives jobs to idle computers. Ideal resource-sharing algorithm should have following characteristics: Dynamics, decentralized, and heterogeneous. Proposed enhanced receiver-initiated dynamic algorithm (ERIDA) for resource sharing fulfills all above criteria. Provides method balancing workload among hosts, resulting in improvement in response time and throughput performance of total system. Adjusts dynamically to traffic load of each station.

  3. Three-Dimensional Temperature Field Simulation for the Rotor of an Asynchronous Motor

    ERIC Educational Resources Information Center

    Wang, Yanwu; Fan, Chunli; Yang, Li; Sun, Fengrui

    2010-01-01

    A three-dimensional heat transfer model is built according to the rotor structure of an asynchronous motor, and three-dimensional temperature fields of the rotor under different working conditions, such as the unloaded, rated loaded and that with broken rotor bars, are studied based on the finite element numerical method and experiments. The…

  4. Evaluation of rheological parameters of the axial system using the Transfer Vibration through Spine (TVS) method.

    PubMed

    Panska, Sarka; Piglova, Tereza; Zeman, Josef; Marsik, Frantisek; Lopot, Frantisek; Jelen, Karel

    2016-09-01

    The human motion system reacts to both hypo and hyperactivity loads by changes to the rheological properties of tissues. This study deals with changes to the axial system (AS) compartment. Using the appropriate methodologies and mathematical-physical methods, these changes can be identified and quantified. This study describes the noninvasive TVS (Transfer Vibration through Spine) method, which was applied to assess the AS selected mechanical properties in various modes. A pilot study was conducted on a top-level twelve-year-old girl-gymnast. The data detection was carried out in three cycles, before and after a peak 3.5 hour training session and the next day, after resting, just before the next training. Specifically, the values of selected rheological parameters, the AS damping coefficient b and viscosity μ, were obtained. The dynamics of their changes, in the stated load cycles, has also been shown. The damping coefficient b fell from the value of 0.626 to 0.324 before training and increased to 0.394 after resting. The viscosity coefficient μ showed a similar trend, namely falling from the value of 9.85 [Pa.s] to 2.15 [Pa.s] and then increasing to 3.8 [Pa.s] . With its computational solution, the TVS method,is a diagnostic apparatus making it possible to classify AS properties, both quantitatively and qualitatively, or its chosen segments and their changes, respectively. It can be used in classifying, preventing and treating the consequences of extreme motion and relaxing modes. The TVS application also makes it possible to control AS states over therapeutic, recovery, ergonomic and other loading modes of the human locomotion system.

  5. 46 CFR 112.20-15 - Transfer of emergency loads.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having a Temporary and a Final Emergency Power Source § 112.20-15 Transfer of emergency loads. (a) When the potential of the final emergency power source reaches 85 to 95...

  6. 46 CFR 112.20-15 - Transfer of emergency loads.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having a Temporary and a Final Emergency Power Source § 112.20-15 Transfer of emergency loads. (a) When the potential of the final emergency power source reaches 85 to 95...

  7. 46 CFR 112.20-15 - Transfer of emergency loads.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having a Temporary and a Final Emergency Power Source § 112.20-15 Transfer of emergency loads. (a) When the potential of the final emergency power source reaches 85 to 95...

  8. 46 CFR 112.20-15 - Transfer of emergency loads.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having a Temporary and a Final Emergency Power Source § 112.20-15 Transfer of emergency loads. (a) When the potential of the final emergency power source reaches 85 to 95...

  9. 46 CFR 112.20-15 - Transfer of emergency loads.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Systems Having a Temporary and a Final Emergency Power Source § 112.20-15 Transfer of emergency loads. (a) When the potential of the final emergency power source reaches 85 to 95...

  10. Inverse optimal design of the radiant heating in materials processing and manufacturing

    NASA Astrophysics Data System (ADS)

    Fedorov, A. G.; Lee, K. H.; Viskanta, R.

    1998-12-01

    Combined convective, conductive, and radiative heat transfer is analyzed during heating of a continuously moving load in the industrial radiant oven. A transient, quasi-three-dimensional model of heat transfer between a continuous load of parts moving inside an oven on a conveyor belt at a constant speed and an array of radiant heaters/burners placed inside the furnace enclosure is developed. The model accounts for radiative exchange between the heaters and the load, heat conduction in the load, and convective heat transfer between the moving load and oven environment. The thermal model developed has been used to construct a general framework for an inverse optimal design of an industrial oven as an example. In particular, the procedure based on the Levenberg-Marquardt nonlinear least squares optimization algorithm has been developed to obtain the optimal temperatures of the heaters/burners that need to be specified to achieve a prescribed temperature distribution of the surface of a load. The results of calculations for several sample cases are reported to illustrate the capabilities of the procedure developed for the optimal inverse design of an industrial radiant oven.

  11. Effects of Mental Load and Fatigue on Steady-State Evoked Potential Based Brain Computer Interface Tasks: A Comparison of Periodic Flickering and Motion-Reversal Based Visual Attention.

    PubMed

    Xie, Jun; Xu, Guanghua; Wang, Jing; Li, Min; Han, Chengcheng; Jia, Yaguang

    Steady-state visual evoked potentials (SSVEP) based paradigm is a conventional BCI method with the advantages of high information transfer rate, high tolerance to artifacts and the robust performance across users. But the occurrence of mental load and fatigue when users stare at flickering stimuli is a critical problem in implementation of SSVEP-based BCIs. Based on electroencephalography (EEG) power indices α, θ, θ + α, ratio index θ/α and response properties of amplitude and SNR, this study quantitatively evaluated the mental load and fatigue in both of conventional flickering and the novel motion-reversal visual attention tasks. Results over nine subjects revealed significant mental load alleviation in motion-reversal task rather than flickering task. The interaction between factors of "stimulation type" and "fatigue level" also illustrated the motion-reversal stimulation as a superior anti-fatigue solution for long-term BCI operation. Taken together, our work provided an objective method favorable for the design of more practically applicable steady-state evoked potential based BCIs.

  12. The Circuit Theory Behind Coupled-Mode Magnetic Resonance-Based Wireless Power Transmission.

    PubMed

    Kiani, Mehdi; Ghovanloo, Maysam

    2012-09-01

    Inductive coupling is a viable scheme to wirelessly energize devices with a wide range of power requirements from nanowatts in radio frequency identification tags to milliwatts in implantable microelectronic devices, watts in mobile electronics, and kilowatts in electric cars. Several analytical methods for estimating the power transfer efficiency (PTE) across inductive power transmission links have been devised based on circuit and electromagnetic theories by electrical engineers and physicists, respectively. However, a direct side-by-side comparison between these two approaches is lacking. Here, we have analyzed the PTE of a pair of capacitively loaded inductors via reflected load theory (RLT) and compared it with a method known as coupled-mode theory (CMT). We have also derived PTE equations for multiple capacitively loaded inductors based on both RLT and CMT. We have proven that both methods basically result in the same set of equations in steady state and either method can be applied for short- or midrange coupling conditions. We have verified the accuracy of both methods through measurements, and also analyzed the transient response of a pair of capacitively loaded inductors. Our analysis shows that the CMT is only applicable to coils with high quality factor ( Q ) and large coupling distance. It simplifies the analysis by reducing the order of the differential equations by half compared to the circuit theory.

  13. The Circuit Theory Behind Coupled-Mode Magnetic Resonance-Based Wireless Power Transmission

    PubMed Central

    Kiani, Mehdi; Ghovanloo, Maysam

    2014-01-01

    Inductive coupling is a viable scheme to wirelessly energize devices with a wide range of power requirements from nanowatts in radio frequency identification tags to milliwatts in implantable microelectronic devices, watts in mobile electronics, and kilowatts in electric cars. Several analytical methods for estimating the power transfer efficiency (PTE) across inductive power transmission links have been devised based on circuit and electromagnetic theories by electrical engineers and physicists, respectively. However, a direct side-by-side comparison between these two approaches is lacking. Here, we have analyzed the PTE of a pair of capacitively loaded inductors via reflected load theory (RLT) and compared it with a method known as coupled-mode theory (CMT). We have also derived PTE equations for multiple capacitively loaded inductors based on both RLT and CMT. We have proven that both methods basically result in the same set of equations in steady state and either method can be applied for short- or midrange coupling conditions. We have verified the accuracy of both methods through measurements, and also analyzed the transient response of a pair of capacitively loaded inductors. Our analysis shows that the CMT is only applicable to coils with high quality factor (Q) and large coupling distance. It simplifies the analysis by reducing the order of the differential equations by half compared to the circuit theory. PMID:24683368

  14. The composite load spectra project

    NASA Technical Reports Server (NTRS)

    Newell, J. F.; Ho, H.; Kurth, R. E.

    1990-01-01

    Probabilistic methods and generic load models capable of simulating the load spectra that are induced in space propulsion system components are being developed. Four engine component types (the transfer ducts, the turbine blades, the liquid oxygen posts and the turbopump oxidizer discharge duct) were selected as representative hardware examples. The composite load spectra that simulate the probabilistic loads for these components are typically used as the input loads for a probabilistic structural analysis. The knowledge-based system approach used for the composite load spectra project provides an ideal environment for incremental development. The intelligent database paradigm employed in developing the expert system provides a smooth coupling between the numerical processing and the symbolic (information) processing. Large volumes of engine load information and engineering data are stored in database format and managed by a database management system. Numerical procedures for probabilistic load simulation and database management functions are controlled by rule modules. Rules were hard-wired as decision trees into rule modules to perform process control tasks. There are modules to retrieve load information and models. There are modules to select loads and models to carry out quick load calculations or make an input file for full duty-cycle time dependent load simulation. The composite load spectra load expert system implemented today is capable of performing intelligent rocket engine load spectra simulation. Further development of the expert system will provide tutorial capability for users to learn from it.

  15. A method to model latent heat for transient analysis using NASTRAN

    NASA Technical Reports Server (NTRS)

    Harder, R. L.

    1982-01-01

    A sample heat transfer analysis is demonstrated which includes the heat of fusion. The method can be used to analyze a system with nonconstant specific heat. The enthalpy is introduced as an independent degree of freedom at each node. The user input consists of a curve of temperature as a function of enthalpy, which may include a constant temperature phase change. The basic NASTRAN heat transfer capability is used to model the effects of latent heat with existing direct matrix output and nonlinear load data cards. Although some user care is required, the numerical stability of the integration is quite good when the given recommendations are followed. The theoretical equations used and the NASTRAN techniques are shown.

  16. Development and evaluation of the impulse transfer function technique

    NASA Technical Reports Server (NTRS)

    Mantus, M.

    1972-01-01

    The development of the test/analysis technique known as the impulse transfer function (ITF) method is discussed. This technique, when implemented with proper data processing systems, should become a valuable supplement to conventional dynamic testing and analysis procedures that will be used in the space shuttle development program. The method can relieve many of the problems associated with extensive and costly testing of the shuttle for transient loading conditions. In addition, the time history information derived from impulse testing has the potential for being used to determine modal data for the structure under investigation. The technique could be very useful in determining the time-varying modal characteristics of structures subjected to thermal transients, where conventional mode surveys are difficult to perform.

  17. Transfer cell wall ingrowths and vein loading characteristics in pea leaf discs. [Pisum sativum

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

    Wimmers, L.E.; Turgeon, R.

    1987-04-01

    Transfer cell wall ingrowths are thought to increase transport capacity by increasing plasmalemma surface area. Leaf minor vein phloem transfer cells presumably enhance phloem loading. In Pisum sativum cv. Little marvel grown under different light regimes (150 to 1000 ..mu..mol photons m/sup -2/ sec/sup -1/) there is a positive correlation between light intensity and wall ingrowth area in phloem transfer cells. The extent of ingrowth and correlation to light intensity is greatest in minor veins, decreasing as vein size increases. Vein loading was assayed by floating abraded leaf discs on /sup 14/C-sucrose (10 mM). There is a positive correlation betweenmore » uptake and transfer cell wall area, although the latter increased more than the former. The difference in uptake is stable throughout the photoperiod, and is also stable in mature leaves for at least four days after plants are transfered to a different light intensity. Sucrose uptake is biphasic. The saturable component of uptake is sensitive to light intensity, the Km for sucrose is negatively correlated to light intensity, while V/sub max/remains unchanged.« less

  18. Constant-current control method of multi-function electromagnetic transmitter.

    PubMed

    Xue, Kaichang; Zhou, Fengdao; Wang, Shuang; Lin, Jun

    2015-02-01

    Based on the requirements of controlled source audio-frequency magnetotelluric, DC resistivity, and induced polarization, a constant-current control method is proposed. Using the required current waveforms in prospecting as a standard, the causes of current waveform distortion and current waveform distortion's effects on prospecting are analyzed. A cascaded topology is adopted to achieve 40 kW constant-current transmitter. The responsive speed and precision are analyzed. According to the power circuit of the transmitting system, the circuit structure of the pulse width modulation (PWM) constant-current controller is designed. After establishing the power circuit model of the transmitting system and the PWM constant-current controller model, analyzing the influence of ripple current, and designing an open-loop transfer function according to the amplitude-frequency characteristic curves, the parameters of the PWM constant-current controller are determined. The open-loop transfer function indicates that the loop gain is no less than 28 dB below 160 Hz, which assures the responsive speed of the transmitting system; the phase margin is 45°, which assures the stabilization of the transmitting system. Experimental results verify that the proposed constant-current control method can keep the control error below 4% and can effectively suppress load change caused by the capacitance of earth load.

  19. Constant-current control method of multi-function electromagnetic transmitter

    NASA Astrophysics Data System (ADS)

    Xue, Kaichang; Zhou, Fengdao; Wang, Shuang; Lin, Jun

    2015-02-01

    Based on the requirements of controlled source audio-frequency magnetotelluric, DC resistivity, and induced polarization, a constant-current control method is proposed. Using the required current waveforms in prospecting as a standard, the causes of current waveform distortion and current waveform distortion's effects on prospecting are analyzed. A cascaded topology is adopted to achieve 40 kW constant-current transmitter. The responsive speed and precision are analyzed. According to the power circuit of the transmitting system, the circuit structure of the pulse width modulation (PWM) constant-current controller is designed. After establishing the power circuit model of the transmitting system and the PWM constant-current controller model, analyzing the influence of ripple current, and designing an open-loop transfer function according to the amplitude-frequency characteristic curves, the parameters of the PWM constant-current controller are determined. The open-loop transfer function indicates that the loop gain is no less than 28 dB below 160 Hz, which assures the responsive speed of the transmitting system; the phase margin is 45°, which assures the stabilization of the transmitting system. Experimental results verify that the proposed constant-current control method can keep the control error below 4% and can effectively suppress load change caused by the capacitance of earth load.

  20. The Distribution of Loads on Rivets Connecting a Plate to a Beam under Transverse Loads

    NASA Technical Reports Server (NTRS)

    Vogt, F.

    1947-01-01

    This report gives theoretical discussion of the distribution of leads on rivets connecting a plate to a beam under transverse leads. Two methods of solution are given which are applicable to loads up to the limit of proportionality; in the first the rivets are treated as discrete members, and in the second they are replaced by a continuous system of jointing. A method of solution is also given which is applicable to the case when nonlinear deformations occur in the rivets and the plate, but not in the beam. The methods are illustrated by numerical examples, and these show that the loads carried by the rivets and the plate are less than the values given by classical theory, which does not take into account the slip of the rivets, even below the limit of proportionality. The difference is considerably accentuated when nonlinear deformations occur in the restructure and the beam then carries the greater portion of the bending moment. If the material of the beam has a higher proportional limit and a higher ultimate strength than the material of the plate, there is thus a transfer of load from weaker to stronger material, and this is to the advantage of the structure. The methods given are of simple application and are recommended for use in the design of light-alloy structures when the design lead is likely to be above the proportional limit.

  1. Track/train dynamics test report transfer function test. Volume 1: Test

    NASA Technical Reports Server (NTRS)

    Vigil, R. A.

    1975-01-01

    A description is presented of the transfer function test performed on an open hopper freight car loaded with 80 tons of coal. Test data and a post-test update of the requirements document and test procedure are presented. Included are a statement of the test objective, a description of the test configurations, test facilities, test methods, data acquisition/reduction operations, and a chronological test summary. An index to the data for the three test configurations (X, Y, and Z-axis tests) is presented along with test sequence, run number, test reference, and input parameters.

  2. Optimization of spent fuel pool weir gate driving mechanism

    NASA Astrophysics Data System (ADS)

    Liu, Chao; Du, Lin; Tao, Xinlei; Wang, Shijie; Shang, Ertao; Yu, Jianjiang

    2018-04-01

    Spent fuel pool is crucial facility for fuel storage and nuclear safety, and the spent fuel pool weir gate is the key related equipment. In order to achieve a goal of more efficient driving force transfer, loading during the opening/closing process is analyzed and an optimized calculation method for dimensions of driving mechanism is proposed. The result of optimizing example shows that the method can be applied to weir gates' design with similar driving mechanism.

  3. 40 CFR 60.254 - Standards for coal processing and conveying equipment, coal storage systems, transfer and loading...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for coal processing and conveying equipment, coal storage systems, transfer and loading systems, and open storage piles. 60.254... (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Coal Preparation...

  4. Wireless power transfer system

    DOEpatents

    Wu, Hunter; Sealy, Kylee; Gilchrist, Aaron

    2016-02-23

    A system includes a first stage of an inductive power transfer system with an LCL load resonant converter with a switching section, an LCL tuning circuit, and a primary receiver pad. The IPT system includes a second stage with a secondary receiver pad, a secondary resonant circuit, a secondary rectification circuit, and a secondary decoupling converter. The secondary receiver pad connects to the secondary resonant circuit. The secondary resonant circuit connects to the secondary rectification circuit. The secondary rectification circuit connects to the secondary decoupling converter. The second stage connects to a load. The load includes an energy storage element. The second stage and load are located on a vehicle and the first stage is located at a fixed location. The primary receiver pad wirelessly transfers power to the secondary receiver pad across a gap when the vehicle positions the secondary receiver pad with respect to the primary receiver pad.

  5. The power transfer from the neuromuscular machinery to its load as a vegetative and somatic behaviour.

    PubMed

    Federici, A; Nocera, L

    1990-01-01

    Models have been proposed in literature describing the contraction of visceral and somatic muscles as an interaction between the time-varying elastances of them and the loads they are working against. The aim of this paper is: 1) to make clear similarities between the models of visceral and somatic muscular contraction; 2) to stress the concept that the power transfer from a time-varying elastance to its load is a behaviour, i.e. an interaction between the entire neuromuscular machinery and the surrounding environment; 3) to propose a theory describing the various physiological and pathological behaviours of both visceral and somatic muscles as different ways of coupling between the time-varying muscular elastances and their loads. In this theory it is assumed that the entire neuromuscular machinery acts as a whole to set the most appropriate power transfer to achieve behavioural goals.

  6. Mixed Convective Condensation in Enclosures with Noncondensable Gases

    NASA Astrophysics Data System (ADS)

    Fox, Richard John

    1994-01-01

    A transient, two-dimensional, numerical model was developed in order to study the laminar flow, heat, and mass transfer in a vertical reflux condenser loaded with vapor and noncondensable gas. The simplified model treats the two-component (gas/vapor), two-phase (vapor/liquid) mixture as a continuum by making use of conservation equations for mass continuity, momentum, species, and energy. The liquid mist phase is formed in such a way as to obey one of three conditions: thermodynamic equilibrium, complete nonequilibrium (no mist formation), or partial equilibrium (partial supersaturation). In developing the model, special attention was paid to the formulation of the boundary conditions, global continuity, and numerical efficiency. Two different mixture combinations were used in order to create stable and unstable systems. Steam-helium mixtures (Mv, = 18, Mg = 4) were found to exhibit stable flows with the lighter helium trapped in the upper portion of the condenser, shutting off condensation in that region. Steam-air mixtures (M_ {v}, = 18, Mg = 28) were found to exhibit varying degrees of instability, depending on the noncondensable gas and heat load, owing to the accumulation of the heavy gas near the condensing surface. Under low gas loading cases (Pg = 0.031 kg/m^3) the natural convective fluctuations were found to be weak and the flow was more easily dominated by the forced convective inlet flow and wall suction. At such low gas loadings, stable, asymmetric flow patterns persisted up to high powers. Large gas loadings (Pg = 0.196 kg/m^3) showed much stronger natural convective effects. Regions of counterflowing vapor and gas were found to promote stronger mixing as the power was increased. Regions of noncondensing gas were found to blanket the condenser walls as the suction velocity increased, resulting in a strong resistance to heat and mass transfer and consequent increase in system pressure. Moderate gas loadings (Pg = 0.065 kg/m ^3) were found to exhibit intermediate behavior between the low and high gas loading cases. For the moderate gas loading cases, a bifurcation was found to occur when Re was increased beyond a critical value, forcing the system into one of two stable, distinct flow patterns. Each branch of the bifurcation was found to correspond to the flows that occur in either the low or high gas loading cases, and radically different heat transfer performance was encountered for the same system parameters. The model was also used to simulate experiments conducted in a vertical reflux thermosyphon using steam -air mixtures. The qualitative aspects of the flow were in reasonable agreement between the model and experiment and trends in the local heat transfer were similar. By converting latent heat energy into sensible heat energy, mist formation was found to increase the system temperature and, as a consequence, the overall heat transfer coefficient was lowered. However, the total heat transfer rate was not sensitive to mist formation since the reduction in the latent heat transfer was accompanied by a corresponding increase in the sensible heat transfer, altering the mode but not the magnitude of the total heat transfer.

  7. Dry Transfer Inoculation of Low-Moisture Spices Containing Antimicrobial Compounds.

    PubMed

    Hildebrandt, Ian M; Hu, Chuxuan; Grasso-Kelley, Elizabeth M; Ye, Peiran; Anderson, Nathan M; Keller, Susanne E

    2017-02-01

    Inoculation of a food product for use in subsequent validation studies typically makes use of a high concentration cocktail of microorganisms suspended in aqueous media. However, this inoculation method may prove difficult particularly when the food product is a low-moisture food containing antimicrobial compounds, such as some dried spices. In this study, a dry transfer method for inoculation of clove powder, oregano leaves, ginger powder, and ground black pepper with a five-serovar cocktail of Salmonella was developed and compared with a traditional aqueous inoculation procedure. Spices were inoculated at three levels, 10, 8, and 6 log CFU/g, by using both an aqueous suspension of Salmonella and a dry transfer of Salmonella from previously inoculated silica beads. At the highest inoculation level, the dry transfer method resulted in a significantly higher microbial load (P < 0.05) for ground cloves and oregano, but not for ginger and ground black pepper. At the intermediate inoculation level, differences were apparent only for ginger and black pepper. Inoculation levels of 6 log CFU/g resulted in recoveries below detection limits for both methods of inoculation. Additional examination on the survival of Salmonella on silica beads after inoculation and in clove powder after dry transfer from silica beads showed linear rates of decline, with a rate of -0.011 log CFU/g/day for beads and -0.015 log CFU/g/day for clove powder. The results suggest that dry transfer of Salmonella via inoculated silica beads is a viable alternative when traditional aqueous inoculation is not feasible.

  8. Investigation of Anion-Exchange and Immunoaffinity Particle-Loaded Membranes for the Isolation of Charged Organic Analytes from Water

    USGS Publications Warehouse

    Dombrowski, T.R.; Wilson, G.S.; Thurman, E.M.

    1998-01-01

    Anion-exchange and immunoaffinity particle loaded membranes (PLMs) were investigated as a mechanism for the isolation of charged organic analytes from water. Kinetic properties determined theoretically included dynamic capacity, pressure drop (??P), residence and diffusion times (Tr, Td), and total membrane porosity (???T). These properties were confirmed through experimental evaluation, and the PLM method showed significant improvement over conventional solid-phase extraction (SPE) and ion-exchange formats. Recoveries of more than 90% were observed for a variety of test compounds at flow rates up to 70 mL/min (equipment-limited maximum flow rate). A fast-flow immunoaffinity column was developed using antibodies (Abs) attached to the PLMs. Reproducible recoveries (88% ?? 4%) were observed at flow rates up to 70 mL/min for the antibody (Ab)-loaded PLMs. Findings indicate increased selectivity over anion-exchange PLMs and conventional SPE or ion-exchange methods and rapid Ab-antigen binding rates given the excellent mass-transfer characteristics of the PLMs.

  9. Design and implementation of an air-conditioning system with storage tank for load shifting

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

    Hsu, Y.Y.; Wu, C.J.; Liou, K.L.

    1987-11-01

    The experience with the design, simulation and implementation of an air-conditioning system with chilled water storage tank is presented in this paper. The system is used to shift air-conditioning load of residential and commercial buildings from on-peak to off-peak period. Demand-side load management can thus be achieved if many buildings are equipped with such storage devices. In the design of this system, a lumped-parameter circuit model is first employed to simulate the heat transfer within the air-conditioned building such that the required capacity of the storage tank can be figured out. Then, a set of desirable parameters for the temperaturemore » controller of the system are determined using the parameter plane method and the root locus method. The validity of the proposed mathematical model and design approach is verified by comparing the results obtained from field tests with those from the computer simulations. Cost-benefit analysis of the system is also discussed.« less

  10. Modular adaptive implant based on smart materials.

    PubMed

    Bîzdoacă, N; Tarniţă, Daniela; Tarniţă, D N

    2008-01-01

    Applications of biological methods and systems found in nature to the study and design of engineering systems and modern technology are defined as Bionics. The present paper describes a bionics application of shape memory alloy in construction of orthopedic implant. The main idea of this paper is related to design modular adaptive implants for fractured bones. In order to target the efficiency of medical treatment, the implant has to protect the fractured bone, for the healing period, undertaking much as is possible from the daily usual load of the healthy bones. After a particular stage of healing period is passed, using implant modularity, the load is gradually transferred to bone, assuring in this manner a gradually recover of bone function. The adaptability of this design is related to medical possibility of the physician to made the implant to correspond to patient specifically anatomy. Using a CT realistic numerical bone models, the mechanical simulation of different types of loading of the fractured bones treated with conventional method are presented. The results are commented and conclusions are formulated.

  11. Design and analysis of multifunctional structures for embedded electronics in unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Kothari, Rushabh M.

    Multifunctional structures are a new trend in the aerospace industry for the next generation structural design. Many future structures are expected to be something in addition to a load bearing structure. The design and analysis of multifunctional structures combining structural, electrical and thermal functionalities are presented here. The sandwich beam is considered as a starting point for the load bearing structure and then it is modified with a cavity to embed avionics and thermal controls. The embedded avionics inside the load bearing structure would allow weight reduction of the aerospace vehicle due to elimination of separate electronics housing, interconnects, cables etc. The cavity reduces strength of the structure so various reinforcements methods are evaluated. The result of various reinforcements and their effectiveness are presented. The current generation of electronics produce massive amount of heat. In the case of embedded electronics, the excessive heat presents a major challenge to the structural and heat transfer engineers. The embedded nature of electronics prevents the use of the classical heat dissipative methods such as fans and high velocity air flows, etc. The integrated thermal control of the electronics has been designed using passive heat transfer device and highly optimized particulate composite thermal interface material (TIM). The TIMs are used to fill the air gaps and reduce contact resistance between two surfaces, such as electronics and heat dissipators. The efficiency of TIM directly affects the overall heat transfer ability of the integrated thermal control system. The effect of the particles at micron and nano scales are studied for the particulate composite TIM. The thermal boundary resistance study for the particulate composite TIM with nano silica particles is presented in this thesis. The FEA analysis is used to model thermal boundary resistance and compared with the theoretical micromechanics model. The heat pipes are chosen as a part of passive heat transfer device due to their durability and excellent thermal conductivities. The multifunctional system consisting of all above components is modeled for unmanned aerial vehicle (UAV) at subsonic air speeds to demonstrate the validity of the design.

  12. Evaluation of biolistic gene transfer methods in vivo using non-invasive bioluminescent imaging techniques.

    PubMed

    Xia, Jixiang; Martinez, Angela; Daniell, Henry; Ebert, Steven N

    2011-06-02

    Gene therapy continues to hold great potential for treating many different types of disease and dysfunction. Safe and efficient techniques for gene transfer and expression in vivo are needed to enable gene therapeutic strategies to be effective in patients. Currently, the most commonly used methods employ replication-defective viral vectors for gene transfer, while physical gene transfer methods such as biolistic-mediated ("gene-gun") delivery to target tissues have not been as extensively explored. In the present study, we evaluated the efficacy of biolistic gene transfer techniques in vivo using non-invasive bioluminescent imaging (BLI) methods. Plasmid DNA carrying the firefly luciferase (LUC) reporter gene under the control of the human Cytomegalovirus (CMV) promoter/enhancer was transfected into mouse skin and liver using biolistic methods. The plasmids were coupled to gold microspheres (1 μm diameter) using different DNA Loading Ratios (DLRs), and "shot" into target tissues using a helium-driven gene gun. The optimal DLR was found to be in the range of 4-10. Bioluminescence was measured using an In Vivo Imaging System (IVIS-50) at various time-points following transfer. Biolistic gene transfer to mouse skin produced peak reporter gene expression one day after transfer. Expression remained detectable through four days, but declined to undetectable levels by six days following gene transfer. Maximum depth of tissue penetration following biolistic transfer to abdominal skin was 200-300 μm. Similarly, biolistic gene transfer to mouse liver in vivo also produced peak early expression followed by a decline over time. In contrast to skin, however, liver expression of the reporter gene was relatively stable 4-8 days post-biolistic gene transfer, and remained detectable for nearly two weeks. The use of bioluminescence imaging techniques enabled efficient evaluation of reporter gene expression in vivo. Our results demonstrate that different tissues show different expression kinetics following gene transfer of the same reporter plasmid to different mouse tissues in vivo. We evaluated superficial (skin) and abdominal organ (liver) targets, and found that reporter gene expression peaked within the first two days post-transfer in each case, but declined most rapidly in the skin (3-4 days) compared to liver (10-14 days). This information is essential for designing effective gene therapy strategies in different target tissues.

  13. Creep-induced residual stress strengthening in a Nicalon-fiber-reinforced BMAS-glass-ceramic-matrix composite

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

    Widjaja, S.; Jakus, K.; Ritter, J.E.

    The feasibility of inducing a compressive residual stress in the matrix of a Nicalon-fiber-reinforced BMAS-glass-ceramic-matrix composite through a creep-load transfer treatment was studied. Specimens were crept at 1100 C under constant tensile load to cause load transfer from the matrix to the fibers, then cooled under load. Upon removal of the load at room temperature, the matrix was put into compression by the elastic recovery of the fibers. This compressive residual stress in the matrix increased the room-temperature proportional limit stress of the composite. The increase in the proportional limit stress was found to be dependent upon the applied creepmore » stress, with an increase in creep stress resulting in an increase in the proportional limit stress. Acoustic emission results showed that the onset of significant matrix cracking correlated closely to the proportional limit stress. Changes in the state of residual stress in the matrix were supported by X-ray diffraction results. Fracture surfaces of all specimens exhibited fiber pullout behavior, indicating that the creep-load transfer process did not embrittle the fiber/matrix interface.« less

  14. Non-invasive determination of conjugative transfer of plasmids bearing antibiotic-resistance genes in biofilm-bound bacteria: effects of substrate loading and antibiotic selection

    PubMed Central

    Ma, Hongyan; Bryers, James D.

    2012-01-01

    Biofilms cause much of all human microbial infections. Attempts to eradicate biofilm-based infections rely on disinfectants and antibiotics. Unfortunately, biofilm bacteria are significantly less responsive to antibiotic stressors than their planktonic counterparts. Sublethal doses of antibiotics can actually enhance biofilm formation. Here, we have developed a non-invasive microscopic image analyses to quantify plasmid conjugation within a developing biofilm. Corroborating destructive samples were analyzed by a cultivation-independent flow cytometry analysis and a selective plate count method to cultivate transconjugants. Increases in substrate loading altered biofilm 3-D architecture and subsequently affected the frequency of plasmid conjugation (decreases at least two times) in the absence of any antibiotic selective pressure. More importantly, donor populations in biofilms exposed to a sublethal dose of kanamycin exhibited enhanced transfer efficiency of plasmids containing the kanamycin resistance gene, up to tenfold. However, when stressed with a different antibiotic, imipenem, transfer of plasmids containing the kanR+ gene was not enhanced. These preliminary results suggest biofilm bacteria “sense” antibiotics to which they are resistant, which enhances the spread of that resistance. Confocal scanning microscopy coupled with our non-invasive image analysis was able to estimate plasmid conjugative transfer efficiency either averaged over the entire biofilm landscape or locally with individual biofilm clusters. PMID:22669634

  15. Preparation and application of in-fibre internal standardization solid-phase microextraction.

    PubMed

    Zhao, Wennan; Ouyang, Gangfeng; Pawliszyn, Janusz

    2007-03-01

    The in-fibre standardization method is a novel approach that has been developed for field sampling/sample preparation, in which an internal standard is pre-loaded onto a solid-phase microextraction (SPME) fibre for calibration of the extraction of target analytes in field samples. The same method can also be used for in-vial sample analysis. In this study, different techniques to load the standard to a non-porous SPME fibre were investigated. It was found that the appropriateness of the technique depends on the physical properties of the standards that are used for the analysis. Headspace extraction of the standard dissolved in pumping oil works well for volatile compounds. Conversely, headspace extraction of the pure standard is an effective approach for semi-volatile compounds. For compounds with low volatility, a syringe-fibre transfer method and direct extraction of the standard dissolved in a solvent exhibited a good reproducibility (<5% RSD). The main advantage of the approaches investigated in this study is that the standard generation vials can be reused for hundreds of analyses without exhibiting significant loss. Moreover, most of the standard loading processes studied can be performed automatically, which is efficient and precise. Finally, the standard loading technique and in-fibre standardization method were applied to a complex matrix (milk) and the results illustrated that the matrix effect can be effectively compensated for with this approach.

  16. Analysis, design, and control of a transcutaneous power regulator for artificial hearts.

    PubMed

    Qianhong Chen; Siu Chung Wong; Tse, C K; Xinbo Ruan

    2009-02-01

    Based on a generic transcutaneous transformer model, a remote power supply using a resonant topology for use in artificial hearts is analyzed and designed for easy controllability and high efficiency. The primary and secondary windings of the transcutaneous transformer are positioned outside and inside the human body, respectively. In such a transformer, the alignment and gap may change with external positioning. As a result, the coupling coefficient of the transcutaneous transformer is also varying, and so are the two large leakage inductances and the mutual inductance. Resonant-tank circuits with varying resonant-frequency are formed from the transformer inductors and external capacitors. For a given range of coupling coefficients, an operating frequency corresponding to a particular coupling coefficient can be found, for which the voltage transfer function is insensitive to load. Prior works have used frequency modulation to regulate the output voltage under varying load and transformer coupling. The use of frequency modulation may require a wide control frequency range which may extend well above the load insensitive frequency. In this paper, study of the input-to-output voltage transfer function is carried out, and a control method is proposed to lock the switching frequency at just above the load insensitive frequency for optimized efficiency at heavy loads. Specifically, operation at above resonant of the resonant circuits is maintained under varying coupling-coefficient. Using a digital-phase-lock-loop (PLL), zero-voltage switching is achieved in a full-bridge converter which is also programmed to provide output voltage regulation via pulsewidth modulation (PWM). A prototype transcutaneous power regulator is built and found to to perform excellently with high efficiency and tight regulation under variations of the alignment or gap of the transcutaneous transformer, load and input voltage.

  17. Studying NK cell responses to ectromelia virus infections in mice.

    PubMed

    Fang, Min; Sigal, Luis

    2010-01-01

    Here we describe methods for the in vivo study of antiviral NK cell responses using the mouse Orthopoxvirus ectromelia virus as a model, the agent of mousepox. The methods include those specific for the preparation and use of ectromelia virus such as the production of virus stocks in tissue culture and in live mice, the purification of virus stocks, the titration of virus stocks and virus loads in organs, and the infection of mice. The chapter also includes methods for the specific study of NK cell responses in infected mice such as the preparation of organs (lymph nodes, spleen, and liver) for analysis, the study of NK cell responses by flow cytometry, the adoptive transfer of NK cells, the measurement of NK cell cytolytic activity ex vivo and in vivo, and the determination of NK cell proliferation by bromodeoxyuridine loading or by dilution of carboxyfluorescein diacetate succinimidyl ester (CFSE).

  18. Matching of renewable source of energy generation graphs and electrical load in local energy system

    NASA Astrophysics Data System (ADS)

    Lezhniuk, Petro; Komar, Vyacheslav; Sobchuk, Dmytro; Kravchuk, Sergiy; Kacejko, Piotr; Zavidsky, Vladislav

    2017-08-01

    The paper contains the method of matching generation graph of photovoltaic electric stations and consumers. Characteristic feature of this method is the application of morphometric analysis for assessment of non-uniformity of the integrated graph of energy supply, optimal coefficients of current distribution, that enables by mean of refining the powers, transferring in accordance with the graph , to provide the decrease of electric energy losses in the grid and transport task, as the optimization tool.

  19. Implementation and extension of the impulse transfer function method for future application to the space shuttle project. Volume 2: Program description and user's guide

    NASA Technical Reports Server (NTRS)

    Patterson, G.

    1973-01-01

    The data processing procedures and the computer programs were developed to predict structural responses using the Impulse Transfer Function (ITF) method. There are three major steps in the process: (1) analog-to-digital (A-D) conversion of the test data to produce Phase I digital tapes (2) processing of the Phase I digital tapes to extract ITF's and storing them in a permanent data bank, and (3) predicting structural responses to a set of applied loads. The analog to digital conversion is performed by a standard package which will be described later in terms of the contents of the resulting Phase I digital tape. Two separate computer programs have been developed to perform the digital processing.

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

    Nemec, Patrik, E-mail: patrik.nemec@fstroj.uniza.sk; Malcho, Milan, E-mail: milan.malcho@fstroj.uniza.sk

    This work deal with experimental evaluation of cooling efficiency of cooling device capable transfer high heat fluxes from electric elements to the surrounding. The work contain description of cooling device, working principle of cooling device, construction of cooling device. Experimental part describe the measuring method of device cooling efficiency evaluation. The work results are presented in graphic visualization of temperature dependence of the contact area surface between cooling device evaporator and electronic components on the loaded heat of electronic components in range from 250 to 740 W and temperature dependence of the loop thermosiphon condenser surface on the loaded heatmore » of electronic components in range from 250 to 740 W.« less

  1. Analytical and Experimental Evaluation of the Heat Transfer Distribution over the Surfaces of Turbine Vanes

    NASA Technical Reports Server (NTRS)

    Hylton, L. D.; Mihelc, M. S.; Turner, E. R.; Nealy, D. A.; York, R. E.

    1983-01-01

    Three airfoil data sets were selected for use in evaluating currently available analytical models for predicting airfoil surface heat transfer distributions in a 2-D flow field. Two additional airfoils, representative of highly loaded, low solidity airfoils currently being designed, were selected for cascade testing at simulated engine conditions. Some 2-D analytical methods were examined and a version of the STAN5 boundary layer code was chosen for modification. The final form of the method utilized a time dependent, transonic inviscid cascade code coupled to a modified version of the STAN5 boundary layer code featuring zero order turbulence modeling. The boundary layer code is structured to accommodate a full spectrum of empirical correlations addressing the coupled influences of pressure gradient, airfoil curvature, and free-stream turbulence on airfoil surface heat transfer distribution and boundary layer transitional behavior. Comparison of pedictions made with the model to the data base indicates a significant improvement in predictive capability.

  2. Analytical and experimental evaluation of the heat transfer distribution over the surfaces of turbine vanes

    NASA Astrophysics Data System (ADS)

    Hylton, L. D.; Mihelc, M. S.; Turner, E. R.; Nealy, D. A.; York, R. E.

    1983-05-01

    Three airfoil data sets were selected for use in evaluating currently available analytical models for predicting airfoil surface heat transfer distributions in a 2-D flow field. Two additional airfoils, representative of highly loaded, low solidity airfoils currently being designed, were selected for cascade testing at simulated engine conditions. Some 2-D analytical methods were examined and a version of the STAN5 boundary layer code was chosen for modification. The final form of the method utilized a time dependent, transonic inviscid cascade code coupled to a modified version of the STAN5 boundary layer code featuring zero order turbulence modeling. The boundary layer code is structured to accommodate a full spectrum of empirical correlations addressing the coupled influences of pressure gradient, airfoil curvature, and free-stream turbulence on airfoil surface heat transfer distribution and boundary layer transitional behavior. Comparison of pedictions made with the model to the data base indicates a significant improvement in predictive capability.

  3. A simplified method of evaluating the stress wave environment of internal equipment

    NASA Technical Reports Server (NTRS)

    Colton, J. D.; Desmond, T. P.

    1979-01-01

    A simplified method called the transfer function technique (TFT) was devised for evaluating the stress wave environment in a structure containing internal equipment. The TFT consists of following the initial in-plane stress wave that propagates through a structure subjected to a dynamic load and characterizing how the wave is altered as it is transmitted through intersections of structural members. As a basis for evaluating the TFT, impact experiments and detailed stress wave analyses were performed for structures with two or three, or more members. Transfer functions that relate the wave transmitted through an intersection to the incident wave were deduced from the predicted wave response. By sequentially applying these transfer functions to a structure with several intersections, it was found that the environment produced by the initial stress wave propagating through the structure can be approximated well. The TFT can be used as a design tool or as an analytical tool to determine whether a more detailed wave analysis is warranted.

  4. FRIB Cryogenic Distribution System and Status

    NASA Astrophysics Data System (ADS)

    Ganni, V.; Dixon, K.; Laverdure, N.; Yang, S.; Nellis, T.; Jones, S.; Casagrande, F.

    2015-12-01

    The MSU-FRIB cryogenic distribution system supports the 2 K primary, 4 K primary, and 35 - 55 K shield operation of more than 70 loads in the accelerator and the experimental areas. It is based on JLab and SNS experience with bayonet-type disconnects between the loads and the distribution system for phased commissioning and maintenance. The linac transfer line, which features three separate transfer line segments for additional independence during phased commissioning at 4 K and 2 K, connects the folded arrangement of 49 cryomodules and 4 superconducting dipole magnets and a fourth transfer line supports the separator area cryo loads. The pressure reliefs for the transfer line process lines, located in the refrigeration room outside the tunnel/accelerator area, are piped to be vented outdoors. The transfer line designs integrate supply and return flow paths into a combined vacuum space. The main linac distribution segments are produced in a small number of standard configurations; a prototype of one such configuration has been fabricated at Jefferson Lab and has been installed at MSU to support testing of a prototype FRIB cryomodule.

  5. Numerical Simulation of the Ground Response to the Tire Load Using Finite Element Method

    NASA Astrophysics Data System (ADS)

    Valaskova, Veronika; Vlcek, Jozef

    2017-10-01

    Response of the pavement to the excitation caused by the moving vehicle is one of the actual problems of the civil engineering practice. The load from the vehicle is transferred to the pavement structure through contact area of the tires. Experimental studies show nonuniform distribution of the pressure in the area. This non-uniformity is caused by the flexible nature and the shape of the tire and is influenced by the tire inflation. Several tire load patterns, including uniform distribution and point load, were involved in the numerical modelling using finite element method. Applied tire loads were based on the tire contact forces of the lorry Tatra 815. There were selected two procedures for the calculations. The first one was based on the simplification of the vehicle to the half-part model. The characteristics of the vehicle model were verified by the experiment and by the numerical model in the software ADINA, when vehicle behaviour during the ride was investigated. Second step involved application of the calculated contact forces for the front axle as the load on the multi-layered half space representing the pavement structure. This procedure was realized in the software Plaxis and considered various stress patterns for the load. The response of the ground to the vehicle load was then analyzed. Axisymmetric model was established for this procedure. The paper presents the results of the investigation of the contact pressure distribution and corresponding reaction of the pavement to various load distribution patterns. The results show differences in some calculated quantities for different load patterns, which need to be verified by the experimental way when also ground response should be observed.

  6. Analyzing Potential Grid Impacts from Future In-Motion Roadway Wireless Power Transfer Scenarios

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

    Meintz, Andrew; Gonder, Jeffrey; Jorgenson, Jennie

    This work examines the grid impact of in-motion roadway wireless power transfer through the examination of the electrification of high-capacity roadways inside a metropolitan area. The work uses data from a regional travel study and the Federal Highway Administration's Highway Performance Monitoring System to estimate the electrified roadway's hourly power use throughout a week. The data are then combined with hourly grid load estimates for the same metropolitan area to determine the overlay of traditional grid load with additional load from a future electrified roadway.

  7. Analyzing Potential Grid Impacts from Future In-Motion Roadway Wireless Power Transfer Scenarios: Preprint

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

    Meintz, Andrew; Gonder, Jeffrey; Jorgenson, Jennie

    This work examines the grid impact of in-motion roadway wireless power transfer through the examination of the electrification of high-capacity roadways inside a metropolitan area. The work uses data from a regional travel study and the Federal Highway Administration's Highway Performance Monitoring System to estimate the electrified roadway's hourly power use throughout a week. The data are then combined with hourly grid load estimates for the same metropolitan area to determine the overlay of traditional grid load with additional load from a future electrified roadway.

  8. Elaboration d'une structure de collecte des matieres residuelles selon la Theorie Constructale

    NASA Astrophysics Data System (ADS)

    Al-Maalouf, George

    Currently, more than 80% of the waste management costs are attributed to the waste collection phase. In order to reduce these costs, one current solution resides in the implementation of waste transfer stations. In these stations, at least 3 collection vehicles transfer their load into a larger hauling truck. This cost reduction is based on the principle of economy of scale applied to the transportation sector. This solution improves the efficiency of the system; nevertheless, it does not optimize it. Recent studies show that the compactor trucks used in the collection phase generate significant economic losses mainly due to the frequent stops and the transportation to transfer stations often far from the collection area. This study suggests the restructuring of the waste collection process by dividing it into two phases: the collection phase, and the transportation to the transfer station phase. To achieve this, a deterministic theory called: "the Constructal Theory" (CT) is used. The results show that starting a certain density threshold, the application of the CT minimizes energy losses in the system. In fact, the collection is optimal if it is done using a combination of low capacity vehicle to collect door to door and transfer their charge into high-capacity trucks. These trucks will then transport their load to the transfer station. To minimize the costs of labor, this study proposes the use of Cybernetic Transport System (CTS) as an automated collection vehicle to collect small amounts of waste. Finally, the optimization method proposed is part of a decentralized approach to the collection and treatment of waste. This allows the implementation of multi-process waste treatment facilities on a territory scale. Keywords: Waste collection, Constructal Theory, Cybernetic Transportation Systems.

  9. Design and Development of the Terrain Information Extraction System

    DTIC Science & Technology

    1990-09-04

    system successfully demonstrated relief measurement and orthophoto production, automated feature extraction has remained "the major problem of today’s...the hierarchical relaxation correlation method developed by Helava Associates, Inc. and digital orthophoto production. To achieve this high accuracy...image memory transfer rates will be achieved by using data blocks or "image tiles ." Further, an image fringe loading module will be implemented which

  10. Nanofluids Containing γ-Fe2O3 Nanoparticles and Their Heat Transfer Enhancements

    NASA Astrophysics Data System (ADS)

    Guo, Shou-Zhu; Li, Yang; Jiang, Ji-Sen; Xie, Hua-Qing

    2010-07-01

    Homogeneous and stable magnetic nanofluids containing γ-Fe2O3 nanoparticles were prepared using a two-step method, and their thermal transport properties were investigated. Thermal conductivities of the nanofluids were measured to be higher than that of base fluid, and the enhanced values increase with the volume fraction of the nanoparticles. Viscosity measurements showed that the nanofluids demonstrated Newtonian behavior and the viscosity of the nanofluids depended strongly on the tested temperatures and the nanoparticles loadings. Convective heat transfer coefficients tested in a laminar flow showed that the coefficients increased with the augment of Reynolds number and the volume fraction.

  11. Wind turbine blade fatigue tests: lessons learned and application to SHM system development

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

    Taylor, Stuart G.; Farinholt, Kevin M.; Jeong, Hyomi

    2012-06-28

    This paper presents experimental results of several structural health monitoring (SHM) methods applied to a 9-meter CX-100 wind turbine blade that underwent fatigue loading. The blade was instrumented with piezoelectric transducers, accelerometers, acoustic emission sensors, and foil strain gauges. It underwent harmonic excitation at its first natural frequency using a hydraulically actuated resonant excitation system. The blade was initially excited at 25% of its design load, and then with steadily increasing loads until it failed. Various data were collected between and during fatigue loading sessions. The data were measured over multiple frequency ranges using a variety of acquisition equipment, includingmore » off-the-shelf systems and specially designed hardware developed by the authors. Modal response, diffuse wave-field transfer functions, and ultrasonic guided wave methods were applied to assess the condition of the wind turbine blade. The piezoelectric sensors themselves were also monitored using a sensor diagnostics procedure. This paper summarizes experimental procedures and results, focusing particularly on fatigue crack detection, and concludes with considerations for implementing such damage identification systems, which will be used as a guideline for future SHM system development for operating wind turbine blades.« less

  12. Impact of kinetic mass transfer on free convection in a porous medium

    NASA Astrophysics Data System (ADS)

    Lu, Chunhui; Shi, Liangsheng; Chen, Yiming; Xie, Yueqing; Simmons, Craig T.

    2016-05-01

    We investigate kinetic mass transfer effects on unstable density-driven flow and transport processes by numerical simulations of a modified Elder problem. The first-order dual-domain mass transfer model coupled with a variable-density-flow model is employed to describe transport behavior in porous media. Results show that in comparison to the no-mass-transfer case, a higher degree of instability and more unstable system is developed in the mass transfer case due to the reduced effective porosity and correspondingly a larger Rayleigh number (assuming permeability is independent on the mobile porosity). Given a constant total porosity, the magnitude of capacity ratio (i.e., immobile porosity/mobile porosity) controls the macroscopic plume profile in the mobile domain, while the magnitude of mass transfer timescale (i.e., the reciprocal of the mass transfer rate coefficient) dominates its evolution rate. The magnitude of capacity ratio plays an important role on the mechanism driving the mass flux into the aquifer system. Specifically, for a small capacity ratio, solute loading is dominated by the density-driven transport, while with increasing capacity ratio local mass transfer dominated solute loading may occur at later times. At significantly large times, however, both mechanisms contribute comparably to solute loading. Sherwood Number could be a nonmonotonic function of mass transfer timescale due to complicated interactions of solute between source zone, mobile zone and immobile zone in the top boundary layer, resulting in accordingly a similar behavior of the total mass. The initial assessment provides important insights into unstable density-driven flow and transport in the presence of kinetic mass transfer.

  13. Articular cartilage and subchondral bone in the pathogenesis of osteoarthritis.

    PubMed

    Goldring, Mary B; Goldring, Steven R

    2010-03-01

    The articular surface plays an essential role in load transfer across the joint, and conditions that produce increased load transfer or altered patterns of load distribution accelerate the development of osteoarthritis (OA). Current knowledge segregates the risk factors into two fundamental mechanisms related to the adverse effects of "abnormal" loading on normal cartilage or "normal" loading on abnormal cartilage. Although chondrocytes can modulate their functional state in response to loading, their capacity to repair and modify the surrounding extracellular matrix is limited in comparison to skeletal cells in bone. This differential adaptive capacity underlies the more rapid appearance of detectable skeletal changes, especially after acute injuries that alter joint mechanics. The imbalance in the adaptation of the cartilage and bone disrupts the physiological relationship between these tissues and further contributes to OA pathology. This review focuses on the specific articular cartilage and skeletal features of OA and the putative mechanisms involved in their pathogenesis.

  14. Fine Output Voltage Control Method considering Time-Delay of Digital Inverter System for X-ray Computed Tomography

    NASA Astrophysics Data System (ADS)

    Shibata, Junji; Kaneko, Kazuhide; Ohishi, Kiyoshi; Ando, Itaru; Ogawa, Mina; Takano, Hiroshi

    This paper proposes a new output voltage control for an inverter system, which has time-delay and nonlinear load. In the next generation X-ray computed tomography of a medical device (X-ray CT) that uses the contactless power transfer method, the feedback signal often contains time-delay due to AD/DA conversion and error detection/correction time. When the PID controller of the inverter system is received the adverse effects of the time-delay, the controller often has an overshoot and a oscillated response. In order to overcome this problem, this paper proposes a compensation method based on the Smith predictor for an inverter system having a time-delay and the nonlinear loads which are the diode bridge rectifier and X-ray tube. The proposed compensation method consists of the hybrid Smith predictor system based on an equivalent analog circuit and DSP. The experimental results confirm the validity of the proposed system.

  15. 40 CFR 86.1308-84 - Dynamometer and engine equipment specifications.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... technique involves the calibration of a master load cell (i.e., dynamometer case load cell). This... hydraulically actuated precalibrated master load cell. This calibration is then transferred to the flywheel torque measuring device. The technique involves the following steps: (i) A master load cell shall be...

  16. Effective load transfer by a chromium carbide nanostructure in a multi-walled carbon nanotube/copper matrix composite

    NASA Astrophysics Data System (ADS)

    Cho, Seungchan; Kikuchi, Keiko; Kawasaki, Akira; Kwon, Hansang; Kim, Yangdo

    2012-08-01

    Multi-walled carbon nanotube (MWCNT) reinforced copper (Cu) matrix composites, which exhibit chromium (Cr) carbide nanostructures at the MWCNT/Cu interface, were prepared through a carbide formation using CuCr alloy powder. The fully densified and oriented MWCNTs dispersed throughout the composites were prepared using spark plasma sintering (SPS) followed by hot extrusion. The tensile strengths of the MWCNT/CuCr composites increased with increasing MWCNTs content, while the tensile strength of MWCNT/Cu composite decreased from that of monolithic Cu. The enhanced tensile strength of the MWCNT/CuCr composites is a result of possible load-transfer mechanisms of the interfacial Cr carbide nanostructures. The multi-wall failure of MWCNTs observed in the fracture surface of the MWCNT/CuCr composites indicates an improvement in the load-bearing capacity of the MWCNTs. This result shows that the Cr carbide nanostructures effectively transferred the tensile load to the MWCNTs during fracture through carbide nanostructure formation in the MWCNT/Cu composite.

  17. Parameter Estimation of Actuators for Benchmark Active Control Technology (BACT) Wind Tunnel Model with Analysis of Wear and Aerodynamic Loading Effects

    NASA Technical Reports Server (NTRS)

    Waszak, Martin R.; Fung, Jimmy

    1998-01-01

    This report describes the development of transfer function models for the trailing-edge and upper and lower spoiler actuators of the Benchmark Active Control Technology (BACT) wind tunnel model for application to control system analysis and design. A simple nonlinear least-squares parameter estimation approach is applied to determine transfer function parameters from frequency response data. Unconstrained quasi-Newton minimization of weighted frequency response error was employed to estimate the transfer function parameters. An analysis of the behavior of the actuators over time to assess the effects of wear and aerodynamic load by using the transfer function models is also presented. The frequency responses indicate consistent actuator behavior throughout the wind tunnel test and only slight degradation in effectiveness due to aerodynamic hinge loading. The resulting actuator models have been used in design, analysis, and simulation of controllers for the BACT to successfully suppress flutter over a wide range of conditions.

  18. Transfer film evaluation for shuttle engine turbopump bearing

    NASA Technical Reports Server (NTRS)

    Kannel, J. W.; Dufrane, K. F.

    1981-01-01

    A series of low speed experiments to evaluate the possible occurrence of transfer film lubrication and the effectiveness of burnished films in the shuttle spacecraft main engine thrust bearings were conducted. No evidence of transfer film lubrication was evident, although this could have been the result of the (used) condition of the bearing. Burnished films of either Teflon or Rulon were found to greatly enhance the performance of the bearing. Crush load experiments indicated that the bearing ultimate load capability is on the order of 489,000 N (110,000 pounds). The effect of ball (as well as race) burnishing techniques on bearing performance, different types of burnished films, and transfer film formation are suggested for further study.

  19. Effect of particle momentum transfer on an oblique-shock-wave/laminar-boundary-layer interaction

    NASA Astrophysics Data System (ADS)

    Teh, E.-J.; Johansen, C. T.

    2016-11-01

    Numerical simulations of solid particles seeded into a supersonic flow containing an oblique shock wave reflection were performed. The momentum transfer mechanism between solid and gas phases in the shock-wave/boundary-layer interaction was studied by varying the particle size and mass loading. It was discovered that solid particles were capable of significant modulation of the flow field, including suppression of flow separation. The particle size controlled the rate of momentum transfer while the particle mass loading controlled the magnitude of momentum transfer. The seeding of micro- and nano-sized particles upstream of a supersonic/hypersonic air-breathing propulsion system is proposed as a flow control concept.

  20. Linear and nonlinear dynamic analysis of redundant load path bearingless rotor systems

    NASA Technical Reports Server (NTRS)

    Murthy, V. R.; Shultz, Louis A.

    1994-01-01

    The goal of this research is to develop the transfer matrix method to treat nonlinear autonomous boundary value problems with multiple branches. The application is the complete nonlinear aeroelastic analysis of multiple-branched rotor blades. Once the development is complete, it can be incorporated into the existing transfer matrix analyses. There are several difficulties to be overcome in reaching this objective. The conventional transfer matrix method is limited in that it is applicable only to linear branch chain-like structures, but consideration of multiple branch modeling is important for bearingless rotors. Also, hingeless and bearingless rotor blade dynamic characteristics (particularly their aeroelasticity problems) are inherently nonlinear. The nonlinear equations of motion and the multiple-branched boundary value problem are treated together using a direct transfer matrix method. First, the formulation is applied to a nonlinear single-branch blade to validate the nonlinear portion of the formulation. The nonlinear system of equations is iteratively solved using a form of Newton-Raphson iteration scheme developed for differential equations of continuous systems. The formulation is then applied to determine the nonlinear steady state trim and aeroelastic stability of a rotor blade in hover with two branches at the root. A comprehensive computer program is developed and is used to obtain numerical results for the (1) free vibration, (2) nonlinearly deformed steady state, (3) free vibration about the nonlinearly deformed steady state, and (4) aeroelastic stability tasks. The numerical results obtained by the present method agree with results from other methods.

  1. Study and characterization of a MEMS micromirror device

    NASA Astrophysics Data System (ADS)

    Furlong, Cosme; Pryputniewicz, Ryszard J.

    2004-08-01

    In this paper, advances in our study and characterization of a MEMS micromirror device are presented. The micromirror device, of 510 mm characteristic length, operates in a dynamic mode with a maximum displacement on the order of 10 mm along its principal optical axis and oscillation frequencies of up to 1.3 kHz. Developments are carried on by analytical, computational, and experimental methods. Analytical and computational nonlinear geometrical models are developed in order to determine the optimal loading-displacement operational characteristics of the micromirror. Due to the operational mode of the micromirror, the experimental characterization of its loading-displacement transfer function requires utilization of advanced optical metrology methods. Optoelectronic holography (OEH) methodologies based on multiple wavelengths that we are developing to perform such characterization are described. It is shown that the analytical, computational, and experimental approach is effective in our developments.

  2. Bovine serum albumin nanoparticles loaded with Photosens photosensitizer for effective photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Khanadeev, Vitaly; Khlebtsov, Boris; Packirisamy, Gopinath; Khlebtsov, Nikolai

    2017-03-01

    Polymeric nanoparticles (NPs) are widely used for drug delivery applications due to high biodegradability, low toxicity and high loading capacity. The focus of this study is the development of photosensitizer Photosens (PS) loaded albumin NPs for efficient photodynamic therapy (PDT). To fabricate PS-loaded bovine serum albumin nanoparticles (BSA-PS NPs), we used a coacervation method with glutaraldehyde followed by passive loading of PS. Successful loading of PS was confirmed by appearance of characteristic peak in absorption spectrum which allows to determine the PS loading in BSA NPs. The synthesized BSA-PS NPs demonstrated low toxicity to HeLa cells at therapeutic concentrations of loaded PS. Compared to free PS solution, the synthesized BSA-PS NPs generated the singlet oxygen more effectively under laser irradiation at 660 nm. In addition, due to presence of various chemical groups on the surface of BSA-PS NPs, they are capable to adsorb on cell surface and accumulate in cells due to cellular uptake mechanisms. Owing to combination of PD and cell uptake advantages, BSA-PS NPs demonstrated higher efficacy of photodynamic damage to cancer cells as compared to free PS at equivalent concentrations. These results suggest that non-targeted BSA-PS NPs with high PD activity and low-fabrication costs of are promising candidates for transfer to PD clinic treatments.

  3. Real-time analysis of organic compounds in ship engine aerosol emissions using resonance-enhanced multiphoton ionisation and proton transfer mass spectrometry.

    PubMed

    Radischat, Christian; Sippula, Olli; Stengel, Benjamin; Klingbeil, Sophie; Sklorz, Martin; Rabe, Rom; Streibel, Thorsten; Harndorf, Horst; Zimmermann, Ralf

    2015-08-01

    Organic combustion aerosols from a marine medium-speed diesel engine, capable to run on distillate (diesel fuel) and residual fuels (heavy fuel oil), were investigated under various operating conditions and engine parameters. The online chemical characterisation of the organic components was conducted using a resonance-enhanced multiphoton ionisation time-of-flight mass spectrometer (REMPI TOF MS) and a proton transfer reaction-quadrupole mass spectrometer (PTR-QMS). Oxygenated species, alkenes and aromatic hydrocarbons were characterised. Especially the aromatic hydrocarbons and their alkylated derivatives were very prominent in the exhaust of both fuels. Emission factors of known health-hazardous compounds (e.g. mono- and poly-aromatic hydrocarbons) were calculated and found in higher amounts for heavy fuel oil (HFO) at typical engine loadings. Lower engine loads lead in general to increasing emissions for both fuels for almost every compound, e.g. naphthalene emissions varied for diesel fuel exhaust between 0.7 mg/kWh (75 % engine load, late start of injection (SOI)) and 11.8 mg/kWh (10 % engine load, late SOI) and for HFO exhaust between 3.3 and 60.5 mg/kWh, respectively. Both used mass spectrometric techniques showed that they are particularly suitable methods for online monitoring of combustion compounds and very helpful for the characterisation of health-relevant substances. Graphical abstract Three-dimensional REMPI data of organic species in diesel fuel and heavy fuel oil exhaust.

  4. An improved heat transfer configuration for a solid-core nuclear thermal rocket engine

    NASA Technical Reports Server (NTRS)

    Clark, John S.; Walton, James T.; Mcguire, Melissa L.

    1992-01-01

    Interrupted flow, impingement cooling, and axial power distribution are employed to enhance the heat-transfer configuration of a solid-core nuclear thermal rocket engine. Impingement cooling is introduced to increase the local heat-transfer coefficients between the reactor material and the coolants. Increased fuel loading is used at the inlet end of the reactor to enhance heat-transfer capability where the temperature differences are the greatest. A thermal-hydraulics computer program for an unfueled NERVA reactor core is employed to analyze the proposed configuration with attention given to uniform fuel loading, number of channels through the impingement wafers, fuel-element length, mass-flow rate, and wafer gap. The impingement wafer concept (IWC) is shown to have heat-transfer characteristics that are better than those of the NERVA-derived reactor at 2500 K. The IWC concept is argued to be an effective heat-transfer configuration for solid-core nuclear thermal rocket engines.

  5. Strain Distribution in a Kennedy Class I Implant Assisted Removable Partial Denture under Various Loading Conditions

    PubMed Central

    Shahmiri, Reza; Aarts, John M.; Bennani, Vincent; Swain, Michael V.

    2013-01-01

    Purpose. This in vitro study investigates how unilateral and bilateral occlusal loads are transferred to an implant assisted removable partial denture (IARPD). Materials and Methods. A duplicate model of a Kennedy class I edentulous mandibular arch was made and then a conventional removable partial denture (RPD) fabricated. Two Straumann implants were placed in the second molar region, and the prosthesis was modified to accommodate implant retained ball attachments. Strain gages were incorporated into the fitting surface of both the framework and acrylic to measure microstrain (μStrain). The IARPD was loaded to 120Ns unilaterally and bilaterally in three different loading positions. Statistical analysis was carried out using SPSS version 18.0 (SPSS, Inc., Chicago, IL, USA) with an alpha level of 0.05 to compare the maximum μStrain values of the different loading conditions. Results. During unilateral and bilateral loading the maximum μStrain was predominantly observed in a buccal direction. As the load was moved anteriorly the μStrain increased in the mesial area. Unilateral loading resulted in a twisting of the structure and generated a strain mismatch between the metal and acrylic surfaces. Conclusions. Unilateral loading created lateral and vertical displacement of the IARPD. The curvature of the dental arch resulted in a twisting action which intensified as the unilateral load was moved anteriorly. PMID:23737788

  6. Heat and mass transfer during the cryopreservation of a bioartificial liver device: a computational model.

    PubMed

    Balasubramanian, Saravana K; Coger, Robin N

    2005-01-01

    Bioartificial liver devices (BALs) have proven to be an effective bridge to transplantation for cases of acute liver failure. Enabling the long-term storage of these devices using a method such as cryopreservation will ensure their easy off the shelf availability. To date, cryopreservation of liver cells has been attempted for both single cells and sandwich cultures. This study presents the potential of using computational modeling to help develop a cryopreservation protocol for storing the three dimensional BAL: Hepatassist. The focus is upon determining the thermal and concentration profiles as the BAL is cooled from 37 degrees C-100 degrees C, and is completed in two steps: a cryoprotectant loading step and a phase change step. The results indicate that, for the loading step, mass transfer controls the duration of the protocol, whereas for the phase change step, when mass transfer is assumed negligible, the latent heat released during freezing is the control factor. The cryoprotocol that is ultimately proposed considers time, cooling rate, and the temperature gradients that the cellular space is exposed to during cooling. To our knowledge, this study is the first reported effort toward designing an effective protocol for the cryopreservation of a three-dimensional BAL device.

  7. 46 CFR 13.127 - Service: General.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... discharged at the same time, a person may receive credit for only one transfer, one loading, and one... dates, the number and kinds of transfers the applicant has participated in, and the number of transfers... satisfaction of the signer that he or she is fully capable of supervising transfers of liquid cargo, including...

  8. 46 CFR 13.127 - Service: General.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... discharged at the same time, a person may receive credit for only one transfer, one loading, and one... dates, the number and kinds of transfers the applicant has participated in, and the number of transfers... satisfaction of the signer that he or she is fully capable of supervising transfers of liquid cargo, including...

  9. 46 CFR 13.127 - Service: General.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... discharged at the same time, a person may receive credit for only one transfer, one loading, and one... dates, the number and kinds of transfers the applicant has participated in, and the number of transfers... satisfaction of the signer that he or she is fully capable of supervising transfers of liquid cargo, including...

  10. 46 CFR 13.127 - Service: General.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... discharged at the same time, a person may receive credit for only one transfer, one loading, and one... dates, the number and kinds of transfers the applicant has participated in, and the number of transfers... satisfaction of the signer that he or she is fully capable of supervising transfers of liquid cargo, including...

  11. Allogeneic lymphocytes persist and traffic in feral MHC-matched mauritian cynomolgus macaques.

    PubMed

    Greene, Justin M; Burwitz, Benjamin J; Blasky, Alex J; Mattila, Teresa L; Hong, Jung Joo; Rakasz, Eva G; Wiseman, Roger W; Hasenkrug, Kim J; Skinner, Pamela J; O'Connor, Shelby L; O'Connor, David H

    2008-06-11

    Thus far, live attenuated SIV has been the most successful method for vaccinating macaques against pathogenic SIV challenge; however, it is not clear what mechanisms are responsible for this protection. Adoptive transfer studies in mice have been integral to understanding live attenuated vaccine protection in models like Friend virus. Previous adoptive transfers in primates have failed as transferred cells are typically cleared within hours after transfer. Here we describe adoptive transfer studies in Mauritian origin cynomolgus macaques (MCM), a non-human primate model with limited MHC diversity. Cells transferred between unrelated MHC-matched macaques persist for at least fourteen days but are rejected within 36 hours in MHC-mismatched macaques. Cells trafficked from the blood to peripheral lymphoid tissues within 12 hours of transfer. MHC-matched MCM provide the first viable primate model for adoptive transfer studies. Because macaques infected with SIV are the best model for HIV/AIDS pathogenesis, we can now directly study the correlates of protective immune responses to AIDS viruses. For example, plasma viral loads following pathogenic SIV challenge are reduced by several orders of magnitude in macaques previously immunized with attenuated SIV. Adoptive transfer of lymphocyte subpopulations from vaccinated donors into SIV-naïve animals may define the immune mechanisms responsible for protection and guide future vaccine development.

  12. Device for measuring hole elongation in a bolted joint

    NASA Technical Reports Server (NTRS)

    Wichorek, Gregory R. (Inventor)

    1987-01-01

    A device to determine the operable failure mode of mechanically fastened lightweight composite joints by measuring the hole elongation of a bolted joint is disclosed. The double-lap joint test apparatus comprises a stud, a test specimen having a hole, two load transfer plates, and linear displacement measuring instruments. The test specimen is sandwiched between the two load transfer plates and clamped together with the stud. Spacer washers are placed between the test specimen and each load transfer plate to provide a known, controllable area for the determination of clamping forces around the hole of the specimen attributable to bolt torque. The spacer washers also provide a gap for the mounting of reference angles on each side of the test specimen. Under tensile loading, elongation of the hole of the test specimen causes the stud to move away from the reference angles. This displacement is measured by the voltage output of two linear displacement measuring instruments that are attached to the stud and remain in contact with the reference angles throughout the tensile loading. The present invention obviates previous problems in obtaining specimen deformation measurements by monitoring the reference angles to the test specimen and the linear displacement measuring instruments to the stud.

  13. Patient Transfers and Risk of Back Injury: Protocol for a Prospective Cohort Study With Technical Measurements of Exposure.

    PubMed

    Vinstrup, Jonas; Madeleine, Pascal; Jakobsen, Markus Due; Jay, Kenneth; Andersen, Lars Louis

    2017-11-08

    More than one third of nurses experience musculoskeletal pain several times during a normal work week. Consistent use of assistive devices during patient transfers is associated with a lower risk of occupational back injuries and low back pain (LBP). While uncertainties exist regarding which type of assistive devices most efficiently prevent LBP, exposure assessments using technological advancements allow for quantification of muscle load and body positions during common work tasks. The main objectives of this study are (1) to quantify low back and neck/shoulder muscle load in Danish nurses during patient transfers performed with different types of assistive devices, and (2) to combine the exposure profile for each type of assistive device with fortnightly questionnaires to identify the importance of muscle load (intensity and frequency of transfers) and body position (degree of back inclination and frequency) on LBP intensity and risk of back injury during a patient transfer. A combination of technical measurements (n=50) and a prospective study design (n=2000) will be applied on a cohort of female nurses in Danish hospitals. The technical measurements will be comprised of surface electromyography and accelerometers, with the aim of quantifying muscle load and body positions during various patient transfers, including different types of assistive devices throughout a workday. The study will thereby gather measurements during real-life working conditions. The prospective cohort study will consist of questionnaires at baseline and 1-year follow-up, as well as follow-up via email every other week for one year on questions regarding the frequency of patient transfers, use of assistive devices, intensity of LBP, and back injuries related to patient transfers. The objective measurements on muscle load and body positions during patient handlings will be applied to the fortnightly replies regarding frequency of patient transfer and use of different assistive devices, in order to identify risk factors for back injuries related to patient transfers and intensity of LBP. Data collection is scheduled to commence during the winter of 2017. The design of this study is novel in its combination of technical measurements applied on a prospective cohort, and the results will provide important information about which assistive devices are associated with intensity of LBP and risk of back injury related to patient transfers. Furthermore, this study will shed light on the dose-response relationship between intensity, duration, and frequency of patient transfers and the intensity of LPB in Danish nurses, and will thereby help to guide and improve electronic health practices among this population. ©Jonas Vinstrup, Pascal Madeleine, Markus Due Jakobsen, Kenneth Jay, Lars Louis Andersen. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 08.11.2017.

  14. 78 FR 13213 - Regional Reliability Standard PRC-006-NPCC-1- Automatic Underfrequency Load Shedding

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-27

    ...; Order No. 775] Regional Reliability Standard PRC-006-NPCC-1--Automatic Underfrequency Load Shedding... transferred to the system upon loss of the facility.'' \\27\\ Compensatory load shedding is automatic shedding of load adequate to compensate for the loss of a generator due to the generator tripping early (i.e...

  15. Efficiency estimation method of three-wired AC to DC line transfer

    NASA Astrophysics Data System (ADS)

    Solovev, S. V.; Bardanov, A. I.

    2018-05-01

    The development of power semiconductor converters technology expands the scope of their application to medium voltage distribution networks (6-35 kV). Particularly rectifiers and inverters of appropriate power capacity complement the topology of such voltage level networks with the DC links and lines. The article presents a coefficient that allows taking into account the increase of transmission line capacity depending on the parameters of it. The application of the coefficient is presented by the example of transfer three-wired AC line to DC in various methods. Dependences of the change in the capacity from the load power factor of the line and the reactive component of the resistance of the transmission line are obtained. Conclusions are drawn about the most efficient ways of converting a three-wired AC line to direct current.

  16. Using Whole-House Field Tests to Empirically Derive Moisture Buffering Model Inputs

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

    Woods, J.; Winkler, J.; Christensen, D.

    2014-08-01

    Building energy simulations can be used to predict a building's interior conditions, along with the energy use associated with keeping these conditions comfortable. These models simulate the loads on the building (e.g., internal gains, envelope heat transfer), determine the operation of the space conditioning equipment, and then calculate the building's temperature and humidity throughout the year. The indoor temperature and humidity are affected not only by the loads and the space conditioning equipment, but also by the capacitance of the building materials, which buffer changes in temperature and humidity. This research developed an empirical method to extract whole-house model inputsmore » for use with a more accurate moisture capacitance model (the effective moisture penetration depth model). The experimental approach was to subject the materials in the house to a square-wave relative humidity profile, measure all of the moisture transfer terms (e.g., infiltration, air conditioner condensate) and calculate the only unmeasured term: the moisture absorption into the materials. After validating the method with laboratory measurements, we performed the tests in a field house. A least-squares fit of an analytical solution to the measured moisture absorption curves was used to determine the three independent model parameters representing the moisture buffering potential of this house and its furnishings. Follow on tests with realistic latent and sensible loads showed good agreement with the derived parameters, especially compared to the commonly-used effective capacitance approach. These results show that the EMPD model, once the inputs are known, is an accurate moisture buffering model.« less

  17. Shear transfer capacity of reinforced concrete exposed to fire

    NASA Astrophysics Data System (ADS)

    Ahmad, Subhan; Bhargava, Pradeep; Chourasia, Ajay

    2018-04-01

    Shear transfer capacity of reinforced concrete elements is a function of concrete compressive strength and reinforcement yield strength. Exposure of concrete and steel to elevated temperature reduces their mechanical properties resulting in reduced shear transfer capacity of RC elements. The objective of present study is to find the effect of elevated temperature on shear transfer capacity of reinforced concrete. For this purpose pushoff specimens were casted using normal strength concrete. After curing, specimens were heated to 250°C and 500°C in an electric furnace. Cooled specimens were tested for shear transfer capacity in a universal testing machine. It was found that shear transfer capacity and stiffness (slope of load-slip curve) were reduced when the specimens were heated to 250°C and 500°C. Load level for the initiation of crack slip was found to be decreased as the temperature was increased. A simple analytical approach is also proposed to predict the shear transfer capacity of reinforced concrete after elevated temperature.

  18. Experimental evaluation of cooling efficiency of the high performance cooling device

    NASA Astrophysics Data System (ADS)

    Nemec, Patrik; Malcho, Milan

    2016-06-01

    This work deal with experimental evaluation of cooling efficiency of cooling device capable transfer high heat fluxes from electric elements to the surrounding. The work contain description of cooling device, working principle of cooling device, construction of cooling device. Experimental part describe the measuring method of device cooling efficiency evaluation. The work results are presented in graphic visualization of temperature dependence of the contact area surface between cooling device evaporator and electronic components on the loaded heat of electronic components in range from 250 to 740 W and temperature dependence of the loop thermosiphon condenser surface on the loaded heat of electronic components in range from 250 to 740 W.

  19. A platform for actively loading cargo RNA to elucidate limiting steps in EV-mediated delivery.

    PubMed

    Hung, Michelle E; Leonard, Joshua N

    2016-01-01

    Extracellular vesicles (EVs) mediate intercellular communication through transfer of RNA and protein between cells. Thus, understanding how cargo molecules are loaded and delivered by EVs is of central importance for elucidating the biological roles of EVs and developing EV-based therapeutics. While some motifs modulating the loading of biomolecular cargo into EVs have been elucidated, the general rules governing cargo loading and delivery remain poorly understood. To investigate how general biophysical properties impact loading and delivery of RNA by EVs, we developed a platform for actively loading engineered cargo RNAs into EVs. In our system, the MS2 bacteriophage coat protein was fused to EV-associated proteins, and the cognate MS2 stem loop was engineered into cargo RNAs. Using this Targeted and Modular EV Loading (TAMEL) approach, we identified a configuration that substantially enhanced cargo RNA loading (up to 6-fold) into EVs. When applied to vesicles expressing the vesicular stomatitis virus glycoprotein (VSVG) - gesicles - we observed a 40-fold enrichment in cargo RNA loading. While active loading of mRNA-length (>1.5 kb) cargo molecules was possible, active loading was much more efficient for smaller (~0.5 kb) RNA molecules. We next leveraged the TAMEL platform to elucidate the limiting steps in EV-mediated delivery of mRNA and protein to prostate cancer cells, as a model system. Overall, most cargo was rapidly degraded in recipient cells, despite high EV-loading efficiencies and substantial EV uptake by recipient cells. While gesicles were efficiently internalized via a VSVG-mediated mechanism, most cargo molecules were rapidly degraded. Thus, in this model system, inefficient endosomal fusion or escape likely represents a limiting barrier to EV-mediated transfer. Altogether, the TAMEL platform enabled a comparative analysis elucidating a key opportunity for enhancing EV-mediated delivery to prostate cancer cells, and this technology should be of general utility for investigations and applications of EV-mediated transfer in other systems.

  20. Preparation of Power Distribution System for High Penetration of Renewable Energy Part I. Dynamic Voltage Restorer for Voltage Regulation Pat II. Distribution Circuit Modeling and Validation

    NASA Astrophysics Data System (ADS)

    Khoshkbar Sadigh, Arash

    Part I: Dynamic Voltage Restorer In the present power grids, voltage sags are recognized as a serious threat and a frequently occurring power-quality problem and have costly consequence such as sensitive loads tripping and production loss. Consequently, the demand for high power quality and voltage stability becomes a pressing issue. Dynamic voltage restorer (DVR), as a custom power device, is more effective and direct solutions for "restoring" the quality of voltage at its load-side terminals when the quality of voltage at its source-side terminals is disturbed. In the first part of this thesis, a DVR configuration with no need of bulky dc link capacitor or energy storage is proposed. This fact causes to reduce the size of the DVR and increase the reliability of the circuit. In addition, the proposed DVR topology is based on high-frequency isolation transformer resulting in the size reduction of transformer. The proposed DVR circuit, which is suitable for both low- and medium-voltage applications, is based on dc-ac converters connected in series to split the main dc link between the inputs of dc-ac converters. This feature makes it possible to use modular dc-ac converters and utilize low-voltage components in these converters whenever it is required to use DVR in medium-voltage application. The proposed configuration is tested under different conditions of load power factor and grid voltage harmonic. It has been shown that proposed DVR can compensate the voltage sag effectively and protect the sensitive loads. Following the proposition of the DVR topology, a fundamental voltage amplitude detection method which is applicable in both single/three-phase systems for DVR applications is proposed. The advantages of proposed method include application in distorted power grid with no need of any low-pass filter, precise and reliable detection, simple computation and implementation without using a phased locked loop and lookup table. The proposed method has been verified by simulation and experimental tests under various conditions considering all possible cases such as different amounts of voltage sag depth (VSD), different amounts of point-on-wave (POW) at which voltage sag occurs, harmonic distortion, line frequency variation, and phase jump (PJ). Furthermore, the ripple amount of fundamental voltage amplitude calculated by the proposed method and its error is analyzed considering the line frequency variation together with harmonic distortion. The best and worst detection time of proposed method were measured 1ms and 8.8ms, respectively. Finally, the proposed method has been compared with other voltage sag detection methods available in literature. Part 2: Power System Modeling for Renewable Energy Integration: As power distribution systems are evolving into more complex networks, electrical engineers have to rely on software tools to perform circuit analysis. There are dozens of powerful software tools available in the market to perform the power system studies. Although their main functions are similar, there are differences in features and formatting structures to suit specific applications. This creates challenges for transferring power system circuit models data (PSCMD) between different software and rebuilding the same circuit in the second software environment. The objective of this part of thesis is to develop a Unified Platform (UP) to facilitate transferring PSCMD among different software packages and relieve the challenges of the circuit model conversion process. UP uses a commonly available spreadsheet file with a defined format, for any home software to write data to and for any destination software to read data from, via a script-based application called PSCMD transfer application. The main considerations in developing the UP are to minimize manual intervention and import a one-line diagram into the destination software or export it from the source software, with all details to allow load flow, short circuit and other analyses. In this study, ETAP, OpenDSS, and GridLab-D are considered, and PSCMD transfer applications written in MATLAB have been developed for each of these to read the circuit model data provided in the UP spreadsheet. In order to test the developed PSCMD transfer applications, circuit model data of a test circuit and a power distribution circuit from Southern California Edison (SCE) - a utility company - both built in CYME, were exported into the spreadsheet file according to the UP format. Thereafter, circuit model data were imported successfully from the spreadsheet files into above mentioned software using the PSCMD transfer applications developed for each software. After the SCE studied circuit is transferred into OpenDSS software using the proposed UP scheme and developed application, it has been studied to investigate the impacts of large-scale solar energy penetration. The main challenge of solar energy integration into power grid is its intermittency (i.e., discontinuity of output power) nature due to cloud shading of photovoltaic panels which depends on weather conditions. In order to conduct this study, OpenDSS time-series simulation feature, which is required due to intermittency of solar energy, is utilized. In this study, the impacts of intermittency of solar energy penetration, especially high-variability points, on voltage fluctuation and operation of capacitor bank and voltage regulator is provided. In addition, the necessity to interpolate and resample unequally spaced time-series measurement data and convert them to equally spaced time-series data as well as the effect of resampling time-interval on the amount of error is discussed. Two applications are developed in Matlab to do interpolation and resampling as well as to calculate the amount of error for different resampling time-intervals to figure out the suitable resampling time-interval. Furthermore, an approach based on cumulative distribution, regarding the length for lines/cables types and the power rating for loads, is presented to prioritize which loads, lines and cables the meters should be installed at to have the most effect on model validation.

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

    Huang, Chuanfu; Kresin, Vitaly V., E-mail: kresin@usc.edu

    This note describes a system for transferring a load of high purity lithium metal into a molecular or cluster beam source. A hot loading vessel is thoroughly baked out while empty and overpressured with argon. A clean Li rod is then dropped in through a long narrow tube. The thoroughly degassed interior of the vessel and the rapid melting of the inserted rod facilitate contamination-free transfer of the highly reactive liquid metal into the source oven.

  2. Ultralow-Carbon Nanotube-Toughened Epoxy: The Critical Role of a Double-Layer Interface.

    PubMed

    Liu, Jingwei; Chen, Chao; Feng, Yuezhan; Liao, Yonggui; Ye, Yunsheng; Xie, Xiaolin; Mai, Yiu-Wing

    2018-01-10

    Understanding the chemistry and structure of interfaces within epoxy resins is important for studying the mechanical properties of nanofiller-filled nanocomposites as well as for developing high-performance polymer nanocomposites. Despite the intensive efforts to construct nanofiller/matrix interfaces, few studies have demonstrated an enhanced stress-transferring efficiency while avoiding unfavorable deformation due to undesirable interface fractures. Here, we report an optimized method to prepare epoxy-based nanocomposites whose interfaces are chemically modulated by poly(glycidyl methacrylate)-block-poly(hexyl methacrylate) (PGMA-b-PHMA)-functionalized multiwalled carbon nanotubes (bc@fMWNTs) and also offer a fundamental explanation of crack growth behavior and the toughening mechanism of the resulting nanocomposites. The presence of block copolymers on the surface of the MWNT results in a promising double-layered interface, in which (1) the outer-layered PGMA segment provides good dispersion in and strong interface bonding with the epoxy matrix, which enhances load transfer efficiency and debonding stress, and (2) the interlayered rubbery PHMA segment around the MWNT provides the maximum removable space for nanotubes as well as triggering cavitation while promoting local plastic matrix deformation, for example, shear banding to dissipate fracture energy. An outstanding toughening effect is achieved with only a 0.05 wt % carbon nanotube loading with the bc@fMWNT, that is, needing only a 20-times lower loading to obtain improvements in fracture toughness comparable to epoxy-based nanocomposites. The enhancements of their corresponding ultimate mode-I fracture toughnesses and fracture energies are 4 times higher than those of pristine MWNT-filled epoxy. These results demonstrate that a MWNT/epoxy interface could be optimized by changing the component structure of grafted modifiers, thereby facilitating the transfer of both mechanical load and energy dissipation across the nanofiller/matrix interface. This work provides a new route for the rational design and development of polymer nanocomposites with exceptional mechanical performance.

  3. Efficiency optimization of class-D biomedical inductive wireless power transfer systems by means of frequency adjustment.

    PubMed

    Schormans, Matthew; Valente, Virgilio; Demosthenous, Andreas

    2015-01-01

    Inductive powering for implanted medical devices is a commonly employed technique, that allows for implants to avoid more dangerous methods such as the use of transcutaneous wires or implanted batteries. However, wireless powering in this way also comes with a number of difficulties and conflicting requirements, which are often met by using designs based on compromise. In particular, one aspect common to most inductive power links is that they are driven with a fixed frequency, which may not be optimal depending on factors such as coupling and load. In this paper, a method is proposed in which an inductive power link is driven by a frequency that is maintained at an optimum value f(opt), to ensure that the link is in resonance. In order to maintain this resonance, a phase tracking technique is employed at the primary side of the link; this allows for compensation of changes in coil separation and load. The technique is shown to provide significant improvements in maintained secondary voltage and efficiency for a range of loads when the link is overcoupled.

  4. Method for analyzing the chemical composition of liquid effluent from a direct contact condenser

    DOEpatents

    Bharathan, Desikan; Parent, Yves; Hassani, A. Vahab

    2001-01-01

    A computational modeling method for predicting the chemical, physical, and thermodynamic performance of a condenser using calculations based on equations of physics for heat, momentum and mass transfer and equations of equilibrium thermodynamics to determine steady state profiles of parameters throughout the condenser. The method includes providing a set of input values relating to a condenser including liquid loading, vapor loading, and geometric characteristics of the contact medium in the condenser. The geometric and packing characteristics of the contact medium include the dimensions and orientation of a channel in the contact medium. The method further includes simulating performance of the condenser using the set of input values to determine a related set of output values such as outlet liquid temperature, outlet flow rates, pressures, and the concentration(s) of one or more dissolved noncondensable gas species in the outlet liquid. The method may also include iteratively performing the above computation steps using a plurality of sets of input values and then determining whether each of the resulting output values and performance profiles satisfies acceptance criteria.

  5. A Novel TRM Calculation Method by Probabilistic Concept

    NASA Astrophysics Data System (ADS)

    Audomvongseree, Kulyos; Yokoyama, Akihiko; Verma, Suresh Chand; Nakachi, Yoshiki

    In a new competitive environment, it becomes possible for the third party to access a transmission facility. From this structure, to efficiently manage the utilization of the transmission network, a new definition about Available Transfer Capability (ATC) has been proposed. According to the North American ElectricReliability Council (NERC)’s definition, ATC depends on several parameters, i. e. Total Transfer Capability (TTC), Transmission Reliability Margin (TRM), and Capacity Benefit Margin (CBM). This paper is focused on the calculation of TRM which is one of the security margin reserved for any uncertainty of system conditions. The TRM calculation by probabilistic method is proposed in this paper. Based on the modeling of load forecast error and error in transmission line limitation, various cases of transmission transfer capability and its related probabilistic nature can be calculated. By consideration of the proposed concept of risk analysis, the appropriate required amount of TRM can be obtained. The objective of this research is to provide realistic information on the actual ability of the network which may be an alternative choice for system operators to make an appropriate decision in the competitive market. The advantages of the proposed method are illustrated by application to the IEEJ-WEST10 model system.

  6. Perceptual load in sport and the heuristic value of the perceptual load paradigm in examining expertise-related perceptual-cognitive adaptations.

    PubMed

    Furley, Philip; Memmert, Daniel; Schmid, Simone

    2013-03-01

    In two experiments, we transferred perceptual load theory to the dynamic field of team sports and tested the predictions derived from the theory using a novel task and stimuli. We tested a group of college students (N = 33) and a group of expert team sport players (N = 32) on a general perceptual load task and a complex, soccer-specific perceptual load task in order to extend the understanding of the applicability of perceptual load theory and further investigate whether distractor interference may differ between the groups, as the sport-specific processing task may not exhaust the processing capacity of the expert participants. In both, the general and the specific task, the pattern of results supported perceptual load theory and demonstrates that the predictions of the theory also transfer to more complex, unstructured situations. Further, perceptual load was the only determinant of distractor processing, as we neither found expertise effects in the general perceptual load task nor the sport-specific task. We discuss the heuristic utility of using response-competition paradigms for studying both general and domain-specific perceptual-cognitive adaptations.

  7. Stress Transfer and Structural Failure of Bilayered Material Systems

    NASA Astrophysics Data System (ADS)

    Prieto-Munoz, Pablo Arthur

    Bilayered material systems are common in naturally formed or artificially engineered structures. Understanding how loads transfer within these structural systems is necessary to predict failure and develop effective designs. Existing methods for evaluating the stress transfer in bilayered materials are limited to overly simplified models or require experimental calibration. As a result, these methods have failed to accurately account for such structural failures as the creep induced roofing panel collapse of Boston's I-90 connector tunnel, which was supported by adhesive anchors. The one-dimensional stress analyses currently used for adhesive anchor design cannot account for viscoelastic creep failure, and consequently results in dangerously under-designed structural systems. In this dissertation, a method for determining the two-dimensional stress and displacement fields for a generalized bilayered material system is developed, and proposes a closed-form analytical solution. A general linear-elastic solution is first proposed by decoupling the elastic governing equations from one another through the so-called plane assumption. Based on this general solution, an axisymmetric problem and a plane strain problem are formulated. These are applied to common bilayered material systems such as: (1) concrete adhesive anchors, (2) material coatings, (3) asphalt pavements, and (4) layered sedimentary rocks. The stress and displacement fields determined by this analytical analysis are validated through the use of finite element models. Through the correspondence principle, the linear-elastic solution is extended to consider time-dependent viscoelastic material properties, thus facilitating the analysis of adhesive anchors and asphalt pavements while incorporating their viscoelastic material behavior. Furthermore, the elastic stress analysis can explain the fracturing phenomenon of material coatings, pavements, and layered rocks, successfully predicting their fracture saturation ratio---which is the ratio of fracture spacing to the thickness of the weak layer where an increase in load will not cause any new fractures to form. Moreover, these specific material systems are looked at in the context of existing and novel experimental results, further demonstrating the advantage of the stress transfer analysis proposed. This research provides a closed-form stress solution for various structural systems that is applied to different failure analyses. The versatility of this method is in the flexibility and the ease upon which the stress and displacement field results can be applied to existing stress- or displacement-based structural failure criteria. As presented, this analysis can be directly used to: (1) design adhesive anchoring systems for long-term creep loading, (2) evaluate the fracture mechanics behind bilayered material coatings and pavement overlay systems, and (3) determine the fracture spacing to layer thickness ratio of layered sedimentary rocks. As is shown in the four material systems presented, this general solution has far reaching applications in facilitating design and analysis of typical bilayered structural systems.

  8. Modeling ARRM Xenon Tank Pressurization Using 1D Thermodynamic and Heat Transfer Equations

    NASA Technical Reports Server (NTRS)

    Gilligan, Patrick; Tomsik, Thomas

    2016-01-01

    As a first step in understanding what ground support equipment (GSE) is required to provide external cooling during the loading of 5,000 kg of xenon into 4 aluminum lined composite overwrapped pressure vessels (COPVs), a modeling analysis was performed using Microsoft Excel. The goals of the analysis were to predict xenon temperature and pressure throughout loading at the launch facility, estimate the time required to load one tank, and to get an early estimate of what provisions for cooling xenon might be needed while the tanks are being filled. The model uses the governing thermodynamic and heat transfer equations to achieve these goals. Results indicate that a single tank can be loaded in about 15 hours with reasonable external coolant requirements. The model developed in this study was successfully validated against flight and test data. The first data set is from the Dawn mission which also utilizes solar electric propulsion with xenon propellant, and the second is test data from the rapid loading of a hydrogen cylindrical COPV. The main benefit of this type of model is that the governing physical equations using bulk fluid solid temperatures can provide a quick and accurate estimate of the state of the propellant throughout loading which is much cheaper in terms of computational time and licensing costs than a Computation Fluid Dynamics (CFD) analysis while capturing the majority of the thermodynamics and heat transfer.

  9. Modeling Xenon Tank Pressurization using One-Dimensional Thermodynamic and Heat Transfer Equations

    NASA Technical Reports Server (NTRS)

    Gilligan, Ryan P.; Tomsik, Thomas M.

    2017-01-01

    As a first step in understanding what ground support equipment (GSE) is required to provide external cooling during the loading of 5,000 kg of xenon into 4 aluminum lined composite overwrapped pressure vessels (COPVs), a modeling analysis was performed using Microsoft Excel. The goals of the analysis were to predict xenon temperature and pressure throughout loading at the launch facility, estimate the time required to load one tank, and to get an early estimate of what provisions for cooling xenon might be needed while the tanks are being filled. The model uses the governing thermodynamic and heat transfer equations to achieve these goals. Results indicate that a single tank can be loaded in about 15 hours with reasonable external coolant requirements. The model developed in this study was successfully validated against flight and test data. The first data set is from the Dawn mission which also utilizes solar electric propulsion with xenon propellant, and the second is test data from the rapid loading of a hydrogen cylindrical COPV. The main benefit of this type of model is that the governing physical equations using bulk fluid solid temperatures can provide a quick and accurate estimate of the state of the propellant throughout loading which is much cheaper in terms of computational time and licensing costs than a Computation Fluid Dynamics (CFD) analysis while capturing the majority of the thermodynamics and heat transfer.

  10. Optimizing physicians' instruction of PACS through e-learning: cognitive load theory applied.

    PubMed

    Devolder, P; Pynoo, B; Voet, T; Adang, L; Vercruysse, J; Duyck, P

    2009-03-01

    This article outlines the strategy used by our hospital to maximize the knowledge transfer to referring physicians on using a picture archiving and communication system (PACS). We developed an e-learning platform underpinned by the cognitive load theory (CLT) so that in depth knowledge of PACS' abilities becomes attainable regardless of the user's prior experience with computers. The application of the techniques proposed by CLT optimizes the learning of the new actions necessary to obtain and manipulate radiological images. The application of cognitive load reducing techniques is explained with several examples. We discuss the need to safeguard the physicians' main mental processes to keep the patient's interests in focus. A holistic adoption of CLT techniques both in teaching and in configuration of information systems could be adopted to attain this goal. An overview of the advantages of this instruction method is given both on the individual and organizational level.

  11. Mass transfer from a circular cylinder: Effects of flow unsteadiness and slight nonuniformities

    NASA Technical Reports Server (NTRS)

    Marziale, M. L.; Mayle, R. E.

    1984-01-01

    Experiments were performed to determine the effect of periodic variations in the angle of the flow incident to a turbine blade on its leading edge heat load. To model this situation, measurements were made on a circular cylinder oscillating rotationally in a uniform steady flow. A naphthalene mass transfer technique was developed and used in the experiments and heat transfer rates are inferred from the results. The investigation consisted of two parts. In the first, a stationary cylinder was used and the transfer rate was measured for Re = 75,000 to 110,000 and turbulence levels from .34 percent to 4.9 percent. Comparisons with both theory and the results of others demonstrate that the accuracy and repeatability of the developed mass transfer technique is about + or - 2 percent, a large improvement over similar methods. In the second part identical flow conditions were used but the cylinder was oscillated. A Strouhal number range from .0071 to .1406 was covered. Comparisons of the unsteady and steady results indicate that the magnitude of the effect of oscillation is small and dependent on the incident turbulence conditions.

  12. A research program for improving heat transfer prediction for the laminar to turbulent transition region of turbine vanes/blades

    NASA Technical Reports Server (NTRS)

    Simon, Frederick F.

    1993-01-01

    A program sponsored by NASA for the investigation of the heat transfer in the transition region of turbine vanes and blades with the objective of improving the capability for predicting heat transfer is described. The accurate prediction of gas-side heat transfer is important to the determination of turbine longevity, engine performance, and developmental costs. The need for accurate predictions will become greater as the operating temperatures and stage loading levels of advanced turbine engines increase. The present methods for predicting transition shear stress and heat transfer on turbine blades are based on incomplete knowledge and are largely empirical. To meet the objective of the NASA program, a team approach consisting of researchers from government, universities, a research institute, and a small business is presented. The research is divided into the areas of experiments, direct numerical simulations (DNS), and turbulence modeling. A summary of the results to date is given for the above research areas in a high-disturbance environment (bypass transition) with a discussion of the model development necessary for use in numerical codes.

  13. Method for separating water soluble organics from a process stream by aqueous biphasic extraction

    DOEpatents

    Chaiko, David J.; Mego, William A.

    1999-01-01

    A method for separating water-miscible organic species from a process stream by aqueous biphasic extraction is provided. An aqueous biphase system is generated by contacting a process stream comprised of water, salt, and organic species with an aqueous polymer solution. The organic species transfer from the salt-rich phase to the polymer-rich phase, and the phases are separated. Next, the polymer is recovered from the loaded polymer phase by selectively extracting the polymer into an organic phase at an elevated temperature, while the organic species remain in a substantially salt-free aqueous solution. Alternatively, the polymer is recovered from the loaded polymer by a temperature induced phase separation (cloud point extraction), whereby the polymer and the organic species separate into two distinct solutions. The method for separating water-miscible organic species is applicable to the treatment of industrial wastewater streams, including the extraction and recovery of complexed metal ions from salt solutions, organic contaminants from mineral processing streams, and colorants from spent dye baths.

  14. Experimental and Numerical Research of Stress-Strain State of Homogeneous Soil Massif at Interaction with Single Barrette

    NASA Astrophysics Data System (ADS)

    Ter-Martirosyan, Z. G.; Ter-Martirosyan, A. Z.; Sidorov, V. V.

    2017-11-01

    Deep foundations are used for the design of high-rise buildings due to a large pressure transfer on the soil base. The foundations of buildings sometimes use barrettes which are able to perceive significant vertical and horizontal loads due to improved lateral surface. Barrettes have increased load bearing capacity as compared with large diameter piles. In modern practice the interaction between barrettes and soil is investigated by analytical and numerical methods and has no sufficient experimental confirmation. The review of experimental methods for the research of the intense stress-strain state of the uniform soil massif at interaction with elements of a deep foundation is provided in this article. Experimental research are planned with the use of laboratory stand for the purpose of qualitative data obtaining on the interaction barrettes with an assessment of a settlement model adequacy and also at the research of the intense stress-strain state by numerical methods.

  15. A Method for Optimal Load Dispatch of a Multi-zone Power System with Zonal Exchange Constraints

    NASA Astrophysics Data System (ADS)

    Hazarika, Durlav; Das, Ranjay

    2018-04-01

    This paper presented a method for economic generation scheduling of a multi-zone power system having inter zonal operational constraints. For this purpose, the generator rescheduling for a multi area power system having inter zonal operational constraints has been represented as a two step optimal generation scheduling problem. At first, the optimal generation scheduling has been carried out for the zone having surplus or deficient generation with proper spinning reserve using co-ordination equation. The power exchange required for the deficit zones and zones having no generation are estimated based on load demand and generation for the zone. The incremental transmission loss formulas for the transmission lines participating in the power transfer process among the zones are formulated. Using these, incremental transmission loss expression in co-ordination equation, the optimal generation scheduling for the zonal exchange has been determined. Simulation is carried out on IEEE 118 bus test system to examine the applicability and validity of the method.

  16. Recovering Aerodynamic Side Loads on Rocket Nozzles using Quasi-Static Strain-Gage Measurements

    NASA Technical Reports Server (NTRS)

    Brown, Andrew; Ruf, Joseph H.; McDaniels, David M.

    2009-01-01

    During over-expanded operation of rocket nozzles, which is defined to be when the exit pressure is greater than internal pressure over some part of the nozzle, the nozzle will experience a transverse forcing function due to the pressure differential across the nozzle wall. Over-expansion occurs during the nozzle start-up and shutdown transient, even in high-altitude engines, because most test facilities cannot completely reproduce the near-vacuum pressures at those altitudes. During this transient, the pressure differential moves axially down the nozzle as it becomes pressurized, but this differential is never perfectly symmetric circumferentially. The character of the forcing function is highly complex and defined by a series of restricted and free shock separations. The subject of this paper is the determination of the magnitude of this loading during sub-scale testing via measurement of the structural dynamic response of the nozzle and its support structure. An initial attempt at back-calculating this load using the inverse of the transfer function was performed, but this attempt was shown to be highly susceptible to numerical error. The final method chosen was to use statically calibrated strain data and to filter out the system fundamental frequency such that the measured response yields close to the correct dynamic loading function. This method was shown to capture 93% of the pressure spectral energy using controlled load shaker testing. This method is one of the only practical ways for the inverse determination of the forcing function for non-stationary excitations, and, to the authors' knowledge, has not been described in the literature to date.

  17. Recent advances in understanding the reinforcing ability and mechanism of carbon nanotubes in ceramic matrix composites.

    PubMed

    Estili, Mehdi; Sakka, Yoshio

    2014-12-01

    Since the discovery of carbon nanotubes (CNTs), commonly referred to as ultimate reinforcement, the main purpose for fabricating CNT-ceramic matrix composites has been mainly to improve the fracture toughness and strength of the ceramic matrix materials. However, there have been many studies reporting marginal improvements or even the degradation of mechanical properties. On the other hand, those studies claiming noticeable toughening measured using indentation, which is an indirect/unreliable characterization method, have not demonstrated the responsible mechanisms applicable to the nanoscale, flexible CNTs; instead, those studies proposed those classical methods applicable to microscale fiber/whisker reinforced ceramics without showing any convincing evidence of load transfer to the CNTs. Therefore, the ability of CNTs to directly improve the macroscopic mechanical properties of structural ceramics has been strongly questioned and debated in the last ten years. In order to properly discuss the reinforcing ability (and possible mechanisms) of CNTs in a ceramic host material, there are three fundamental questions to our knowledge at both the nanoscale and macroscale levels that need to be addressed: (1) does the intrinsic load-bearing ability of CNTs change when embedded in a ceramic host matrix?; (2) when there is an intimate atomic-level interface without any chemical reaction with the matrix, could one expect any load transfer to the CNTs along with effective load bearing by them during crack propagation?; and (3) considering their nanometer-scale dimensions, flexibility and radial softness, are the CNTs able to improve the mechanical properties of the host ceramic matrix at the macroscale when individually, intimately and uniformly dispersed? If so, how? Also, what is the effect of CNT concentration in such a defect-free composite system? Here, we briefly review the recent studies addressing the above fundamental questions. In particular, we discuss the new reinforcing mechanism at the nanoscale responsible for unprecedented, simultaneous mechanical improvements and highlight the scalable processing method enabling the fabrication of defect-free CNT-concentered ceramics and CNT-graded composites with unprecedented properties. Finally, possible future directions will be briefly presented.

  18. Recent advances in understanding the reinforcing ability and mechanism of carbon nanotubes in ceramic matrix composites

    PubMed Central

    Estili, Mehdi; Sakka, Yoshio

    2014-01-01

    Since the discovery of carbon nanotubes (CNTs), commonly referred to as ultimate reinforcement, the main purpose for fabricating CNT–ceramic matrix composites has been mainly to improve the fracture toughness and strength of the ceramic matrix materials. However, there have been many studies reporting marginal improvements or even the degradation of mechanical properties. On the other hand, those studies claiming noticeable toughening measured using indentation, which is an indirect/unreliable characterization method, have not demonstrated the responsible mechanisms applicable to the nanoscale, flexible CNTs; instead, those studies proposed those classical methods applicable to microscale fiber/whisker reinforced ceramics without showing any convincing evidence of load transfer to the CNTs. Therefore, the ability of CNTs to directly improve the macroscopic mechanical properties of structural ceramics has been strongly questioned and debated in the last ten years. In order to properly discuss the reinforcing ability (and possible mechanisms) of CNTs in a ceramic host material, there are three fundamental questions to our knowledge at both the nanoscale and macroscale levels that need to be addressed: (1) does the intrinsic load-bearing ability of CNTs change when embedded in a ceramic host matrix?; (2) when there is an intimate atomic-level interface without any chemical reaction with the matrix, could one expect any load transfer to the CNTs along with effective load bearing by them during crack propagation?; and (3) considering their nanometer-scale dimensions, flexibility and radial softness, are the CNTs able to improve the mechanical properties of the host ceramic matrix at the macroscale when individually, intimately and uniformly dispersed? If so, how? Also, what is the effect of CNT concentration in such a defect-free composite system? Here, we briefly review the recent studies addressing the above fundamental questions. In particular, we discuss the new reinforcing mechanism at the nanoscale responsible for unprecedented, simultaneous mechanical improvements and highlight the scalable processing method enabling the fabrication of defect-free CNT-concentered ceramics and CNT-graded composites with unprecedented properties. Finally, possible future directions will be briefly presented. PMID:27877730

  19. Particle Shape Effect on Macroscopic Behaviour of Underground Structures: Numerical and Experimental Study

    NASA Astrophysics Data System (ADS)

    Szarf, Krzysztof; Combe, Gael; Villard, Pascal

    2015-02-01

    The mechanical performance of underground flexible structures such as buried pipes or culverts made of plastics depend not only on the properties of the structure, but also on the material surrounding it. Flexible drains can deflect by 30% with the joints staying tight, or even invert. Large deformations of the structure are difficult to model in the framework of Finite Element Method, but straightforward in Discrete Element Methods. Moreover, Discrete Element approach is able to provide information about the grain-grain and grain-structure interactions at the microscale. This paper presents numerical and experimental investigations of flexible buried pipe behaviour with focus placed on load transfer above the buried structure. Numerical modeling was able to reproduce the experimental results. Load repartition was observed, being affected by a number of factors such as particle shape, pipe friction and pipe stiffness.

  20. Extension of Weighted Sum of Gray Gas Data to Mathematical Simulation of Radiative Heat Transfer in a Boiler with Gas-Soot Media

    PubMed Central

    Nouri-Borujerdi, Ali; Kazi, Salim Newaz

    2014-01-01

    In this study an expression for soot absorption coefficient is introduced to extend the weighted-sum-of-gray gases data to the furnace medium containing gas-soot mixture in a utility boiler 150 MWe. Heat transfer and temperature distribution of walls and within the furnace space are predicted by zone method technique. Analyses have been done considering both cases of presence and absence of soot particles at 100% load. To validate the proposed soot absorption coefficient, the expression is coupled with the Taylor and Foster's data as well as Truelove's data for CO2-H2O mixture and the total emissivities are calculated and compared with the Truelove's parameters for 3-term and 4-term gray gases plus two soot absorption coefficients. In addition, some experiments were conducted at 100% and 75% loads to measure furnace exit gas temperature as well as the rate of steam production. The predicted results show good agreement with the measured data at the power plant site. PMID:25143981

  1. Extension of weighted sum of gray gas data to mathematical simulation of radiative heat transfer in a boiler with gas-soot media.

    PubMed

    Gharehkhani, Samira; Nouri-Borujerdi, Ali; Kazi, Salim Newaz; Yarmand, Hooman

    2014-01-01

    In this study an expression for soot absorption coefficient is introduced to extend the weighted-sum-of-gray gases data to the furnace medium containing gas-soot mixture in a utility boiler 150 MWe. Heat transfer and temperature distribution of walls and within the furnace space are predicted by zone method technique. Analyses have been done considering both cases of presence and absence of soot particles at 100% load. To validate the proposed soot absorption coefficient, the expression is coupled with the Taylor and Foster's data as well as Truelove's data for CO2-H2O mixture and the total emissivities are calculated and compared with the Truelove's parameters for 3-term and 4-term gray gases plus two soot absorption coefficients. In addition, some experiments were conducted at 100% and 75% loads to measure furnace exit gas temperature as well as the rate of steam production. The predicted results show good agreement with the measured data at the power plant site.

  2. Unveiling the Semicoherent Interface with Definite Orientation Relationships between Reinforcements and Matrix in Novel Al3BC/Al Composites.

    PubMed

    Zhao, Yongfeng; Qian, Zhao; Ma, Xia; Chen, Houwen; Gao, Tong; Wu, Yuying; Liu, Xiangfa

    2016-10-05

    High-strength lightweight Al-based composites are promising materials for a wide range of applications. To provide high performance, a strong bonding interface for effective load transfer from the matrix to the reinforcement is essential. In this work, the novel Al 3 BC reinforced Al composites have been in situ fabricated through a liquid-solid reaction method and the bonding interface between Al 3 BC and Al matrix has been unveiled. The HRTEM characterizations on the Al 3 BC/Al interface verify it to be a semicoherent bonding structure with definite orientation relationships: (0001) Al 3 BC //(11̅1) Al ;[112̅0] Al 3 BC //[011] Al . Periodic arrays of geometrical misfit dislocations are also observed along the interface at each (0001) Al 3 BC plane or every five (11̅1) Al planes. This kind of interface between the reinforcement and the matrix is strong enough for effective load transfer, which would lead to the evidently improved strength and stiffness of the introduced new Al 3 BC/Al composites.

  3. Process and system for removing impurities from a gas

    DOEpatents

    Henningsen, Gunnar; Knowlton, Teddy Merrill; Findlay, John George; Schlather, Jerry Neal; Turk, Brian S

    2014-04-15

    A fluidized reactor system for removing impurities from a gas and an associated process are provided. The system includes a fluidized absorber for contacting a feed gas with a sorbent stream to reduce the impurity content of the feed gas; a fluidized solids regenerator for contacting an impurity loaded sorbent stream with a regeneration gas to reduce the impurity content of the sorbent stream; a first non-mechanical gas seal forming solids transfer device adapted to receive an impurity loaded sorbent stream from the absorber and transport the impurity loaded sorbent stream to the regenerator at a controllable flow rate in response to an aeration gas; and a second non-mechanical gas seal forming solids transfer device adapted to receive a sorbent stream of reduced impurity content from the regenerator and transfer the sorbent stream of reduced impurity content to the absorber without changing the flow rate of the sorbent stream.

  4. Highly fluorescent carbon dots for visible sensing of doxorubicin release based on efficient nanosurface energy transfer.

    PubMed

    Wang, Beibei; Wang, Shujun; Wang, Yanfang; Lv, Yan; Wu, Hao; Ma, Xiaojun; Tan, Mingqian

    2016-01-01

    To prepare fluorescent carbon dots for loading cationic anticancer drug through donor-quenched nanosurface energy transfer in visible sensing of drug release. Highly fluorescent carbon dots (CDs) were prepared by a facile hydrothermal approach from citric acid and o-phenylenediamine. The obtained CDs showed a high quantum yield of 46 % and exhibited good cytocompatibility even at 1 mg/ml. The cationic anticancer drug doxorubicin (DOX) can be loaded onto the negatively charged CDs through electrostatic interactions. Additionally, the fluorescent CDs feature reversible donor-quenched mode nanosurface energy transfer. When loading the energy receptor DOX, the donor CDs' fluorescence was switched "off", while it turned "on" again after DOX release from the surface through endocytic uptake. Most DOX molecules were released from the CDs after 6 h incubation and entered cell nuclear region after 8 h, suggesting the drug delivery system may have potential for visible sensing in drug release.

  5. Bulk refrigeration of fruits and vegetables. Part 2: Computer algorithm for heat loads and moisture loss

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

    Becker, B.; Misra, A.; Fricke, B.A.

    1997-12-31

    A computer algorithm was developed that estimates the latent and sensible heat loads due to the bulk refrigeration of fruits and vegetables. The algorithm also predicts the commodity moisture loss and temperature distribution which occurs during refrigeration. Part 1 focused upon the thermophysical properties of commodities and the flowfield parameters which govern the heat and mass transfer from fresh fruits and vegetables. This paper, Part 2, discusses the modeling methodology utilized in the current computer algorithm and describes the development of the heat and mass transfer models. Part 2 also compares the results of the computer algorithm to experimental datamore » taken from the literature and describes a parametric study which was performed with the algorithm. In addition, this paper also reviews existing numerical models for determining the heat and mass transfer in bulk loads of fruits and vegetables.« less

  6. The best features of diamond nanothread for nanofibre applications

    NASA Astrophysics Data System (ADS)

    Zhan, Haifei; Zhang, Gang; Tan, Vincent B. C.; Gu, Yuantong

    2017-03-01

    Carbon fibres have attracted interest from both the scientific and engineering communities due to their outstanding physical properties. Here we report that recently synthesized ultrathin diamond nanothread not only possesses excellent torsional deformation capability, but also excellent interfacial load-transfer efficiency. Compared with (10,10) carbon nanotube bundles, the flattening of nanotubes is not observed in diamond nanothread bundles, which leads to a high-torsional elastic limit that is almost three times higher. Pull-out tests reveal that the diamond nanothread bundle has an interface transfer load of more than twice that of the carbon nanotube bundle, corresponding to an order of magnitude higher in terms of the interfacial shear strength. Such high load-transfer efficiency is attributed to the strong mechanical interlocking effect at the interface. These intriguing features suggest that diamond nanothread could be an excellent candidate for constructing next-generation carbon fibres.

  7. Effect of the connection gap on the heat-load characteristics of a liquid nitrogen bayonet coupling

    NASA Astrophysics Data System (ADS)

    Tsai, H. H.; Liu, C. P.; Hsiao, F. Z.; Huang, T. Y.; Li, H. C.; Chiou, W. S.; Chang, S. H.; Lin, T. F.

    2012-12-01

    A transfer system for liquid nitrogen (LN2) installed at National Synchrotron Radiation Research Center (NSRRC) to provide LN2 required for the superconducting equipment and experimental stations has a LN2 transfer line of length 160 m and pipeline of inner diameter 25 mm, a phase separator (250 L) and an automatic filling station. The end uses include two cryogenic systems, one Superconducting Radio Frequency (SRF) cavity, five superconducting magnets, monochromators for the beam line and filling of mobile Dewars. The transfer line is segmented and connected with bayonet couplings. The aim of this work was to investigate, by numerical simulation, the effects on the heat load of the gap thickness of the bayonet assembly and the thickness of vacuum insulation. A numerical correlation was created that has become a basis to minimize the head load for future design of bayonet couplings.

  8. Coherently Enhanced Wireless Power Transfer.

    PubMed

    Krasnok, Alex; Baranov, Denis G; Generalov, Andrey; Li, Sergey; Alù, Andrea

    2018-04-06

    Extraction of electromagnetic energy by an antenna from impinging external radiation is at the basis of wireless communications and wireless power transfer (WPT). The maximum of transferred energy is ensured when the antenna is conjugately matched, i.e., when it is resonant and it has an equal coupling with free space and its load. This condition, however, can be easily affected by changes in the environment, preventing optimal operation of a WPT system. Here, we introduce the concept of coherently enhanced WPT that allows us to bypass this difficulty and achieve dynamic control of power transfer. The approach relies on coherent excitation of the waveguide connected to the antenna load with a backward propagating signal of specific amplitude and phase. This signal creates a suitable interference pattern at the load resulting in a modification of the local wave impedance, which in turn enables conjugate matching and a largely increased amount of extracted energy. We develop a simple theoretical model describing this concept, demonstrate it with full-wave numerical simulations for the canonical example of a dipole antenna, and verify experimentally in both near-field and far-field regimes.

  9. Coherently Enhanced Wireless Power Transfer

    NASA Astrophysics Data System (ADS)

    Krasnok, Alex; Baranov, Denis G.; Generalov, Andrey; Li, Sergey; Alù, Andrea

    2018-04-01

    Extraction of electromagnetic energy by an antenna from impinging external radiation is at the basis of wireless communications and wireless power transfer (WPT). The maximum of transferred energy is ensured when the antenna is conjugately matched, i.e., when it is resonant and it has an equal coupling with free space and its load. This condition, however, can be easily affected by changes in the environment, preventing optimal operation of a WPT system. Here, we introduce the concept of coherently enhanced WPT that allows us to bypass this difficulty and achieve dynamic control of power transfer. The approach relies on coherent excitation of the waveguide connected to the antenna load with a backward propagating signal of specific amplitude and phase. This signal creates a suitable interference pattern at the load resulting in a modification of the local wave impedance, which in turn enables conjugate matching and a largely increased amount of extracted energy. We develop a simple theoretical model describing this concept, demonstrate it with full-wave numerical simulations for the canonical example of a dipole antenna, and verify experimentally in both near-field and far-field regimes.

  10. High power solar array switching regulation

    NASA Technical Reports Server (NTRS)

    Decker, D. K.; Cassinelli, J.; Valgora, M.

    1981-01-01

    It is pointed out that spacecraft utilization projections for the 1980s and beyond show a trend toward extended lifetimes and larger electric power systems. The need for improved power management and energy transfer arising in connection with this trend has resulted in the conduction of a Solar Array Switching Power Management study. A description is presented of initial development work performed in the study, taking into account the characteristics for three mission classes. Attention is given to the manned LEO platform (250-kW average load), the unmanned GEO platform (50-kW average load), and an ion propulsion orbit transfer vehicle (50- to 250 kW load).

  11. 33 CFR 154.510 - Loading arms.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Loading arms. 154.510 Section 154.510 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION FACILITIES TRANSFERRING OIL OR HAZARDOUS MATERIAL IN BULK Equipment Requirements § 154.510 Loading arms. (a...

  12. 33 CFR 154.510 - Loading arms.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Loading arms. 154.510 Section 154.510 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION FACILITIES TRANSFERRING OIL OR HAZARDOUS MATERIAL IN BULK Equipment Requirements § 154.510 Loading arms. (a...

  13. 15-Month-Olds’ Transfer of Learning between Touch Screen and Real-World Displays: Language Cues and Cognitive Loads

    PubMed Central

    Zack, Elizabeth; Gerhardstein, Peter; Meltzoff, Andrew N.; Barr, Rachel

    2012-01-01

    Infants have difficulty transferring information between 2D and 3D sources. The current study extends Zack et al.’s (2009) touch screen imitation task to examine whether the addition of specific language cues significantly facilitates 15-month-olds’ transfer of learning between touch screens and real-world 3D objects. The addition of two kinds of linguistic cues (object label plus verb or nonsense name) did not elevate action imitation significantly above levels observed when such language cues were not used. Language cues hindered infants’ performance in the 3D→2D direction of transfer, but only for the object label plus verb condition. The lack of a facilitative effect of language is discussed in terms of competing cognitive loads imposed by conjointly transferring information across dimensions and processing linguistic cues in an action imitation task at this age. PMID:23121508

  14. A Frequency-Domain Multipath Parameter Estimation and Mitigation Method for BOC-Modulated GNSS Signals

    PubMed Central

    Sun, Chao; Feng, Wenquan; Du, Songlin

    2018-01-01

    As multipath is one of the dominating error sources for high accuracy Global Navigation Satellite System (GNSS) applications, multipath mitigation approaches are employed to minimize this hazardous error in receivers. Binary offset carrier modulation (BOC), as a modernized signal structure, is adopted to achieve significant enhancement. However, because of its multi-peak autocorrelation function, conventional multipath mitigation techniques for binary phase shift keying (BPSK) signal would not be optimal. Currently, non-parametric and parametric approaches have been studied specifically aiming at multipath mitigation for BOC signals. Non-parametric techniques, such as Code Correlation Reference Waveforms (CCRW), usually have good feasibility with simple structures, but suffer from low universal applicability for different BOC signals. Parametric approaches can thoroughly eliminate multipath error by estimating multipath parameters. The problems with this category are at the high computation complexity and vulnerability to the noise. To tackle the problem, we present a practical parametric multipath estimation method in the frequency domain for BOC signals. The received signal is transferred to the frequency domain to separate out the multipath channel transfer function for multipath parameter estimation. During this process, we take the operations of segmentation and averaging to reduce both noise effect and computational load. The performance of the proposed method is evaluated and compared with the previous work in three scenarios. Results indicate that the proposed averaging-Fast Fourier Transform (averaging-FFT) method achieves good robustness in severe multipath environments with lower computational load for both low-order and high-order BOC signals. PMID:29495589

  15. Changing climate and nutrient transfers: Evidence from high temporal resolution concentration-flow dynamics in headwater catchments.

    PubMed

    Ockenden, M C; Deasy, C E; Benskin, C McW H; Beven, K J; Burke, S; Collins, A L; Evans, R; Falloon, P D; Forber, K J; Hiscock, K M; Hollaway, M J; Kahana, R; Macleod, C J A; Reaney, S M; Snell, M A; Villamizar, M L; Wearing, C; Withers, P J A; Zhou, J G; Haygarth, P M

    2016-04-01

    We hypothesise that climate change, together with intensive agricultural systems, will increase the transfer of pollutants from land to water and impact on stream health. This study builds, for the first time, an integrated assessment of nutrient transfers, bringing together a) high-frequency data from the outlets of two surface water-dominated, headwater (~10km(2)) agricultural catchments, b) event-by-event analysis of nutrient transfers, c) concentration duration curves for comparison with EU Water Framework Directive water quality targets, d) event analysis of location-specific, sub-daily rainfall projections (UKCP, 2009), and e) a linear model relating storm rainfall to phosphorus load. These components, in combination, bring innovation and new insight into the estimation of future phosphorus transfers, which was not available from individual components. The data demonstrated two features of particular concern for climate change impacts. Firstly, the bulk of the suspended sediment and total phosphorus (TP) load (greater than 90% and 80% respectively) was transferred during the highest discharge events. The linear model of rainfall-driven TP transfers estimated that, with the projected increase in winter rainfall (+8% to +17% in the catchments by 2050s), annual event loads might increase by around 9% on average, if agricultural practices remain unchanged. Secondly, events following dry periods of several weeks, particularly in summer, were responsible for high concentrations of phosphorus, but relatively low loads. The high concentrations, associated with low flow, could become more frequent or last longer in the future, with a corresponding increase in the length of time that threshold concentrations (e.g. for water quality status) are exceeded. The results suggest that in order to build resilience in stream health and help mitigate potential increases in diffuse agricultural water pollution due to climate change, land management practices should target controllable risk factors, such as soil nutrient status, soil condition and crop cover. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Non-Fourier based thermal-mechanical tissue damage prediction for thermal ablation.

    PubMed

    Li, Xin; Zhong, Yongmin; Smith, Julian; Gu, Chengfan

    2017-01-02

    Prediction of tissue damage under thermal loads plays important role for thermal ablation planning. A new methodology is presented in this paper by combing non-Fourier bio-heat transfer, constitutive elastic mechanics as well as non-rigid motion of dynamics to predict and analyze thermal distribution, thermal-induced mechanical deformation and thermal-mechanical damage of soft tissues under thermal loads. Simulations and comparison analysis demonstrate that the proposed methodology based on the non-Fourier bio-heat transfer can account for the thermal-induced mechanical behaviors of soft tissues and predict tissue thermal damage more accurately than classical Fourier bio-heat transfer based model.

  17. Non-Fourier based thermal-mechanical tissue damage prediction for thermal ablation

    PubMed Central

    Li, Xin; Zhong, Yongmin; Smith, Julian; Gu, Chengfan

    2017-01-01

    ABSTRACT Prediction of tissue damage under thermal loads plays important role for thermal ablation planning. A new methodology is presented in this paper by combing non-Fourier bio-heat transfer, constitutive elastic mechanics as well as non-rigid motion of dynamics to predict and analyze thermal distribution, thermal-induced mechanical deformation and thermal-mechanical damage of soft tissues under thermal loads. Simulations and comparison analysis demonstrate that the proposed methodology based on the non-Fourier bio-heat transfer can account for the thermal-induced mechanical behaviors of soft tissues and predict tissue thermal damage more accurately than classical Fourier bio-heat transfer based model. PMID:27690290

  18. Optimization of Nanowire-Resistance Load Logic Inverter.

    PubMed

    Hashim, Yasir; Sidek, Othman

    2015-09-01

    This study is the first to demonstrate characteristics optimization of nanowire resistance load inverter. Noise margins and inflection voltage of transfer characteristics are used as limiting factors in this optimization. Results indicate that optimization depends on resistance value. Increasing of load resistor tends to increasing in noise margins until saturation point, increasing load resistor after this point will not improve noise margins significantly.

  19. Experimental and Numerical Investigation on the Bearing and Failure Mechanism of Multiple Pillars Under Overburden

    NASA Astrophysics Data System (ADS)

    Zhou, Zilong; Chen, Lu; Zhao, Yuan; Zhao, Tongbin; Cai, Xin; Du, Xueming

    2017-04-01

    To reveal the mechanical response of a multi-pillar supporting system under external loads, compressive tests were carried out on single-pillar and double-pillar specimens. The digital speckle correlation method and acoustic emission technique were applied to record and analyse information of the deformation and failure processes. Numerical simulations with the software programme PFC2D were also conducted. In the compressive process of the double-pillar system, if both individual pillars have the same mechanical properties, each pillar deforms similarly and reaches the critical stable state almost simultaneously by sharing equal loads. If the two individual pillars have different mechanical properties, the pillar with higher elastic modulus or lower strength would be damaged and lose its bearing capacity firstly. The load would then be transferred to the other pillar under a load redistribution process. When the pillar with higher strength is strong enough, the load carried by the pillar system would increase again. However, the maximum bearing load of the double-pillar system is smaller than the sum of peak load of individual pillars. The study also indicates that the strength, elastic modulus, and load state of pillars all influence the supporting capacity of the pillar system. In underground space engineering, the appropriate choice of pillar dimensions and layout may play a great role in preventing the occurrence of cascading pillar failure.

  20. Internet traffic load balancing using dynamic hashing with flow volume

    NASA Astrophysics Data System (ADS)

    Jo, Ju-Yeon; Kim, Yoohwan; Chao, H. Jonathan; Merat, Francis L.

    2002-07-01

    Sending IP packets over multiple parallel links is in extensive use in today's Internet and its use is growing due to its scalability, reliability and cost-effectiveness. To maximize the efficiency of parallel links, load balancing is necessary among the links, but it may cause the problem of packet reordering. Since packet reordering impairs TCP performance, it is important to reduce the amount of reordering. Hashing offers a simple solution to keep the packet order by sending a flow over a unique link, but static hashing does not guarantee an even distribution of the traffic amount among the links, which could lead to packet loss under heavy load. Dynamic hashing offers some degree of load balancing but suffers from load fluctuations and excessive packet reordering. To overcome these shortcomings, we have enhanced the dynamic hashing algorithm to utilize the flow volume information in order to reassign only the appropriate flows. This new method, called dynamic hashing with flow volume (DHFV), eliminates unnecessary flow reassignments of small flows and achieves load balancing very quickly without load fluctuation by accurately predicting the amount of transferred load between the links. In this paper we provide the general framework of DHFV and address the challenges in implementing DHFV. We then introduce two algorithms of DHFV with different flow selection strategies and show their performances through simulation.

  1. Quality factor concept in piezoceramic transformer performance description.

    PubMed

    Mezheritsky, Alex V

    2006-02-01

    A new general approach based on the quality factor concept to piezoceramic transformer (PT) performance description is proposed. The system's quality factor, material elastic anisotropy, and coupling factors of the input and output sections of an electrically excited and electrically loaded PT fully characterize its resonance and near-resonance behavior. The PT efficiency, transformation ratio, and input and output power were analytically analyzed and simulated as functions of the load and frequency for the simplest classical Langevin-type and Rosen-type PT designs. A new formulation of the electrical input impedance allows one to separate the power consumed by PT from the power transferred into the load. The system's PT quality factor takes into account losses in each PT "input-output-load" functional components. The loading process is changing PT input electrical impedance on the way that under loading the minimum series impedance is increasing and the maximum parallel impedance is decreasing coincidentally. The quality-factors ratio, between the states of fully loaded and nonloaded PT, is one of the best measures of PTs dynamic performance--practically, the lower the ratio is, the better PT efficiency. A simple and effective method for the loaded PT quality factor determination is proposed. As was found, a piezoceramic with low piezoelectric anisotropy is required to provide maximum PT efficiency and higher corresponding voltage gain. Limitations on the PT output voltage and power, caused by nonlinear effects in piezoceramics, were established.

  2. The transfer of movement sequences: effects of decreased and increased load.

    PubMed

    Muehlbauer, Thomas; Panzer, Stefan; Shea, Charles H

    2007-06-01

    A number of recent experiments have demonstrated that a movement structure develops during the course of learning a movement sequence that provides the basis for transfer. After learning a movement sequence participants have been shown to be able to effectively produce the sequence when movement demands require that the sequence be rescaled in amplitude or produced with an unpractised set of effectors. The purpose of the present experiment was to determine whether participants, after learning a complex 16-element movement sequence with a 0.567-kg load, could also effectively produce the sequence when the load was decreased (0.0 kg) or increased (1.134 kg). The results indicated that participants were able to effectively compensate for decreased and increased load with virtually no changes in performance characteristics (displacement, velocity, acceleration, and pattern of element durations) while electromyographic (EMG) signals demonstrated that smaller (reduced load) or larger forces (increased load) were spontaneously generated to compensate for the change in load. The muscle activation patterns of the biceps and triceps as well as the level of coactivation appeared to be generally upscaled to generate and dissipate the changes in force requirement needed to compensate for the increased load.

  3. Soviet-West German Symposium on Heat Transfer in Cryogenic Systems, 3rd, Kharkov, Ukrainian SSR, Oct. 9-11, 1989, Proceedings

    NASA Astrophysics Data System (ADS)

    1990-04-01

    The papers presented in this volume describe a rotating cryostat for the simulation of mechanical, thermal, and hydraulic processes in superconducting rotors; the problems of cooling the fully superconducting generator stator; an investigation of natural circulation by optical methods; and a method of calculating void fraction for vapor-liquid or gas-liquid flow conditions. Attention is given to an experimental study of the processes of He-3 boiling and condensation, heat transfer in He II at a slow variation of the heat load, an investigation of He II flow crisis in porous media, and cryogenic heat pipes. Other papers are on the stability of rotating superconducting windings for electric machines, the stability of high-temperature superconductors cooled by liquid nitrogen, a calculation of the transpiration cooling of a cylindrical porous wall, and pressure losses in boiling nitrogen flow through horizontal channels.

  4. A frequency control method for regulating wireless power to implantable devices.

    PubMed

    Ping Si; Hu, A P; Malpas, S; Budgett, D

    2008-03-01

    This paper presents a method to regulate the power transferred over a wireless link by adjusting the resonant operating frequency of the primary converter. A significant advantage of this method is that effective power regulation is maintained under variations in load, coupling and circuit parameters. This is particularly important when the wireless supply is used to power implanted medical devices where substantial coupling variations between internal and external systems is expected. The operating frequency is changed dynamically by altering the effective tuning capacitance through soft switched phase control. A thorough analysis of the proposed system has been undertaken, and experimental results verify its functionality.

  5. Technical and economic feasibility of development innovative technological solutions for expansion the adjustment range of high-power CCP

    NASA Astrophysics Data System (ADS)

    Arakelyan, E. K.; Andryushin, A. V.; Burtsev, S. Y.; Andryushin, K. A.

    2017-11-01

    The analysis of technical and parametric constraints on the adjustment range of highpower CCP and recommended technological solutions in the technical literature for their elimination. Established that in the conditions of toughening the requirements for economy, reliability and maneuverability on the part of the system operator with the participation of CCP in control the frequency and power in the power system, existing methods do not ensure the fulfillment of these requirements. The current situation in the energy sector — the lack of highly manoeuvrable power equipment leads to the need participate in control of power consumption diagrams for all types of power plants, including CCP, although initially they were intended primarily for basic loads. Large-scale research conducted at the department of Automated control systems of technological processes, showed the possibility of a significant expansion of the adjustment range of CCP when it operating in the condensing mode and in the heating mode. The report presents the main results of these research for example the CCP-450 and CCP-450T. Various technological solutions are considered: when CCP in the condensation mode — the use of bypass steam distribution schemes, the transfer of a part of the steam turbine into a low-steam mode; when CCP operation in the heating mode — bypass steam distribution and the transfer CCP to gas turbine unit — power heating plants mode with the transfer the steam turbine to the motor mode. Data on the evaluation of the technical and economic feasibility of the proposed innovative technological solutions are presented in comparison with the methods used to solve this problem, which are used in practice, such as passing through the failures of the electric load graphs by transferring the CCP to the mode of operation with incomplete equipment. When comparing, both the economics, and the maneuverability and reliability of the equipment are considered.

  6. Thermal design, rating and second law analysis of shell and tube condensers based on Taguchi optimization for waste heat recovery based thermal desalination plants

    NASA Astrophysics Data System (ADS)

    Chandrakanth, Balaji; Venkatesan, G; Prakash Kumar, L. S. S; Jalihal, Purnima; Iniyan, S

    2018-03-01

    The present work discusses the design and selection of a shell and tube condenser used in Low Temperature Thermal Desalination (LTTD). To optimize the key geometrical and process parameters of the condenser with multiple parameters and levels, a design of an experiment approach using Taguchi method was chosen. An orthogonal array (OA) of 25 designs was selected for this study. The condenser was designed, analysed using HTRI software and the heat transfer area with respective tube side pressure drop were computed using the same, as these two objective functions determine the capital and running cost of the condenser. There was a complex trade off between the heat transfer area and pressure drop in the analysis, however second law analysis was worked out for determining the optimal heat transfer area vs pressure drop for condensing the required heat load.

  7. ACL Fibers Inserting on the Lateral Intercondylar Ridge Carry the Greatest Loads - Are Modern Anatomic Femoral Tunnel Positions Too Low?

    PubMed Central

    Nawabi, Danyal H.; Imhauser, Carl; Tucker, Scott; Nguyen, Joseph; Wickiewicz, Thomas L.; Pearle, Andrew

    2014-01-01

    Objectives: Histological studies have shown that the ACL has a direct and indirect insertion on the femur [1]. The direct insertion is located along the lateral intercondylar ridge and the indirect insertion is located ‘lower’ on the lateral wall of the notch. The trend towards anatomic ACL reconstruction using the anteromedial (AM) portal technique has resulted in ‘lower’ non-isometric femoral tunnel positions and increased graft failures [2]. To our knowledge, the load transfer properties of the direct and indirect ACL insertions have not been studied. This information may help in understanding the increased failures reported with AM portal drilling. The purpose of this study was, 1) to compare the load transferred across the native ACL at the direct and indirect femoral insertions and, 2) to determine the strain behavior of ACL grafts placed at different tunnel locations within the direct and indirect insertions. Methods: Ten fresh-frozen cadaveric knees (mean age, 52.5 years; range, 29-65) were mounted to a six degree of freedom robot. A 134N anterior load at 30 and 90° flexion and a combined valgus (8Nm) and internal (4Nm) rotational moment at 15° flexion were applied. The ACL was subsequently sectioned at the femoral footprint by detaching either the direct or indirect insertion (partially sectioned state), followed by the remainder of the ACL (completely sectioned state) (Figure 1). The kinematics of the intact knee were replayed after each stage of sectioning to determine the loads transferred across the direct and indirect ACL fibers. Loads were expressed as a percentage of the total load borne by the ACL. Strain behaviour was tested by generating 3D models of the femur and tibia from CT scans of each knee. Three tunnel locations (anteromedial bundle [AM], center [C], posterolateral bundle [PL]) each were selected for the direct and indirect insertions and a virtual ACL graft was inserted. The isometry of the virtual graft was calculated through a flexion path of 0 to 90°. Results: Under an anterior tibial load at 30° flexion, the direct insertion carried 83.9% of the total ACL load compared to 16.1% in the indirect insertion (p<0.001). The direct insertion also carried more load at 90° flexion (95.2% vs 4.8%; p<0.001). Under a combined rotatory load at 15° flexion, the direct insertion carried 84.2% of the total ACL load compared to 15.8% in the indirect insertion (p<0.001). A virtual ACL graft placed at the AM position in the direct insertion demonstrated the best strain behaviour with a mean 10.9% change in length. This value was significantly lower (p<0.001) than the isometry at all 3 tunnel positions in the indirect insertion (AM = 18.5%; C = 24.9%; PL = 30.9%). Conclusion: Fibers in the direct insertion of the ACL carry more load than fibers in the indirect insertion. Virtual ACL grafts placed in the ‘higher’ direct location are more isometric than in the ‘lower’ indirect location during range of motion testing. Clinical Relevance: ‘Low’ ACL grafts in the indirect ACL insertion, resulting from AM portal drilling techniques, may experience higher loads in-vivo due to unfavorable biomechanics. With the current shift towards anatomic ACL reconstruction, it may be beneficial to create a ‘higher’ femoral tunnel within the direct insertion at the lateral intercondylar ridge. This position remains anatomical but may also be biomechanically favorable.

  8. A cut-cell finite volume – finite element coupling approach for fluid–structure interaction in compressible flow

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

    Pasquariello, Vito, E-mail: vito.pasquariello@tum.de; Hammerl, Georg; Örley, Felix

    2016-02-15

    We present a loosely coupled approach for the solution of fluid–structure interaction problems between a compressible flow and a deformable structure. The method is based on staggered Dirichlet–Neumann partitioning. The interface motion in the Eulerian frame is accounted for by a conservative cut-cell Immersed Boundary method. The present approach enables sub-cell resolution by considering individual cut-elements within a single fluid cell, which guarantees an accurate representation of the time-varying solid interface. The cut-cell procedure inevitably leads to non-matching interfaces, demanding for a special treatment. A Mortar method is chosen in order to obtain a conservative and consistent load transfer. Wemore » validate our method by investigating two-dimensional test cases comprising a shock-loaded rigid cylinder and a deformable panel. Moreover, the aeroelastic instability of a thin plate structure is studied with a focus on the prediction of flutter onset. Finally, we propose a three-dimensional fluid–structure interaction test case of a flexible inflated thin shell interacting with a shock wave involving large and complex structural deformations.« less

  9. Pterostilbene, a Potent Analog of Resveratrol, a Therapeutic Agent in Prostate Cancer: Epigenetic Mechanisms of Action

    DTIC Science & Technology

    2015-10-01

    protein was loaded in 10-15% SDS-PAGE and transferred onto polyvinylidene difluoride (PVDF) membranes. Membranes were incubated in 5% nonfat dry milk ...epigenetic reader, metastasis-associated protein 1 (MTA1) which is a part of nucleosome remodeling and deacetylation (NuRD) co-repressor complex. MTA1...inhibitor cocktail (ThermoFisher Scientific). Samples containing 70 μg of protein were loaded in 10-12% SDS-PAGE and transferred onto polyvinylidene

  10. A low-frequency versatile wireless power transfer technology for biomedical implants.

    PubMed

    Jiang, Hao; Zhang, Junmin; Lan, Di; Chao; Liou, Shyshenq; Shahnasser, Hamid; Fechter, Richard; Hirose, Shinjiro; Harrison, Michael; Roy, Shuvo

    2013-08-01

    Implantable biomedical sensors and actuators are highly desired in modern medicine. In many cases, the implant's electrical power source profoundly determines its overall size and performance . The inductively coupled coil pair operating at the radio-frequency (RF) has been the primary method for wirelessly delivering electrical power to implants for the last three decades . Recent designs significantly improve the power delivery efficiency by optimizing the operating frequency, coil size and coil distance . However, RF radiation hazard and tissue absorption are the concerns in the RF wireless power transfer technology (RF-WPTT) , . Also, it requires an accurate impedance matching network that is sensitive to operating environments between the receiving coil and the load for efficient power delivery . In this paper, a novel low-frequency wireless power transfer technology (LF-WPTT) using rotating rare-earth permanent magnets is demonstrated. The LF-WPTT is able to deliver 2.967 W power at  ∼ 180 Hz to an 117.1 Ω resistor over 1 cm distance with 50% overall efficiency. Because of the low operating frequency, RF radiation hazard and tissue absorption are largely avoided, and the power delivery efficiency from the receiving coil to the load is independent of the operating environment. Also, there is little power loss observed in the LF-WPTT when the receiving coil is enclosed by non-magnetic implant-grade stainless steel.

  11. Stress distribution along the Fairweather-Queen Charlotte transform fault system

    USGS Publications Warehouse

    Bufe, C.G.

    2005-01-01

    Tectonic loading and Coulomb stress transfer are modeled along the right-lateral Fairweather-Queen Charlotte transform fault system using a threedimensional boundary element program. The loading model includes slip below 12 km along the transform as well as motion of the Pacific plate, and it is consistent with most available Global Positioning System (GPS) displacement rate data. Coulomb stress transfer is shown to have been a weak contributing factor in the failure of the southeastern (Sitka) segment of the Fairweather fault in 1972, hastening the occurrence of the earthquake by only about 8 months. Failure of the Sitka segment was enhanced by a combination of cumulative loading from below (95%) by slip of about 5 cm/yr since 1848, by stress transfer (about 1%) from major earthquakes on straddling segments of the Queen Charlotte fault (M 8.1 in 1949) and the Fairweather fault (M 7.8 in 1958), and by viscoelastic relaxation (about 4%) following the great 1964 Alaska earthquake, modeled by Pollitz et al. (1998). Cumulative stress increases in excess of 7 MPa at a depth of 8 km are projected prior to the M 7.6 earthquake. Coulomb stress transferred by the rupture of the great M 9.2 Alaska earthquake in 1964 (Bufe, 2004a) also hastened the occurrence of the 1972 event, but only by a month or two. Continued tectonic loading over the last half century and stress transfer from the M 7.6 Sitka event has resulted in restressing of the adjacent segments by about 3 MPa at 8 km depth. The occurrence of a M 6.8 earthquake on the northwestern part of the Queen Charlotte fault on 28 June 2004, the largest since 1949, also suggests increased stress. The Cape St. James segment of the fault immediately southeast of the 1949 Queen Charlotte rupture has accumulated about 6 MPa at 8 km through loading since 1900 and stress transfer in 1949. A continued rise in earthquake hazard is indicated for the Alaska panhandle and Queen Charlotte Islands region in the decades ahead as the potential for damaging earthquakes increases.

  12. An electromagnetic induced transparency-like scheme for wireless power transfer using dielectric resonators

    NASA Astrophysics Data System (ADS)

    Elnaggar, Sameh Y.

    2017-02-01

    Similar to the hybridization of three atoms, three coupled resonators interact to form bonding, anti-bonding, and non-bonding modes. The non-bonding mode enables an electromagnetic induced transparency like transfer of energy. Here, the non-bonding mode, resulting from the strong electric coupling of two dielectric resonators and an enclosure, is exploited to show that it is feasible to transfer power over a distance comparable to the operating wavelength. In this scheme, the enclosure acts as a mediator. The strong coupling permits the excitation of the non-bonding mode with high purity. This approach is different from resonant inductive coupling, which works in the sub-wavelength regime. Optimal loads and the corresponding maximum efficiency are determined using two independent methods: Coupled Mode Theory and Circuit modelling. It is shown that, unlike resonant inductive coupling, the figure of merit depends on the enclosure quality and not on the load, which emphasizes the role of the enclosure as a mediator. Briefly after the input excitation is turned on, the energy in the receiver builds up via all coupled and spurious modes. As time elapses, all modes except the non-bonding cease to sustain. Due to the strong coupling between the dielectrics and the enclosure, such systems have unique properties such as high and uniform efficiency over large distances and minimal fringing fields. These properties suggest that electromagnetic induced transparency like schemes that rely on the use of dielectric resonators can be used to power autonomous systems inside an enclosure or find applications when exposure to the fields needs to be minimal. Finite Element computations are used to verify the theoretical predictions by determining the transfer efficiency, field profile, and coupling coefficients for two different systems. It is shown that the three resonators must be present for efficient power transfer; if one or more are removed, the transfer efficiency reduces significantly.

  13. Three-Dimensional Printing of Vitrification Loop Prototypes for Aquatic Species.

    PubMed

    Tiersch, Nolan J; Childress, William M; Tiersch, Terrence R

    2018-05-16

    Vitrification is a method of cryopreservation that freezes samples rapidly, while forming an amorphous solid ("glass"), typically in small (μL) volumes. The goal of this project was to create, by three-dimensional (3D) printing, open vitrification devices based on an elliptical loop that could be efficiently used and stored. Vitrification efforts can benefit from the application of 3D printing, and to begin integration of this technology, we addressed four main variables: thermoplastic filament type, loop length, loop height, and method of loading. Our objectives were to: (1) design vitrification loops with varied dimensions; (2) print prototype loops for testing; (3) evaluate loading methods for the devices; and (4) classify vitrification responses to multiple device configurations. The various configurations were designed digitally using 3D CAD (Computer Aided Design) software, and prototype devices were produced with MakerBot ® 3D printers. The thermoplastic filaments used to produce devices were acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA). Vitrification devices were characterized by the film volumes formed with different methods of loading (pipetting or submersion). Frozen films were classified to determine vitrification quality: zero (opaque, or abundant crystalline ice formation); one (translucent, or partial vitrification), or two (transparent, or substantial vitrification, glass). A published vitrification solution was used to conduct experiments. Loading by pipetting formed frozen films more reliably than by submersion, but submersion yielded fewer filling problems and was more rapid. The loop designs that yielded the highest levels of vitrification enabled rapid transfer of heat, and most often were characterized as being longer and consisting of fewer layers (height). 3D printing can assist standardization of vitrification methods and research, yet can also provide the ability to quickly design and fabricate custom devices when needed.

  14. Fabrication of uniformly dispersed Ag nanoparticles loaded TiO{sub 2} nanotube arrays for enhancing photoelectrochemical and photocatalytic performances under visible light irradiation

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

    Yi, Junhui; Zhang, Shengsen; Wang, Hongjuan

    2014-12-15

    Graphical abstract: Uniformly dispersed Ag nanoparticles (NPs) were successfully loaded on both the outer and inner surface of the TiO{sub 2} nanotube arrays (NTs) through a simple polyol method, which exhibited the enhanced photoelectrochemical and photocatalytic performances under visible-light irradiation due to the more effective separation of photo-generated electron–hole pairs and faster interfacial charge transfer. - Highlights: • Highly dispersed Ag nanoparticles (NPs) are successfully prepared by polyol method. • Ag NPs are uniformly loaded on the surface of the TiO{sub 2} nanotube arrays (NTs). • Ag/TiO{sub 2}-NTs exhibit the enhanced photocatalytic activity under visible-light. • The enhanced photocurrent ismore » explained by electrochemical impedance spectroscopy. - Abstract: Uniformly dispersed Ag nanoparticles (NPs) were successfully loaded on both the outer and inner surface of the TiO{sub 2} nanotube arrays (NTs) through a simple polyol method. The as-prepared Ag/TiO{sub 2}-NTs were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and UV–vis diffusion reflectance spectroscopy. Photoelectrochemical behaviors were investigated via photocurrent response and electrochemical impedance spectroscopy (EIS). Photocatalytic activity of Ag/TiO{sub 2}-NTs was evaluated by degradation of acid orange II under visible light irradiation. The results showed that photocatalytic efficiency of Ag/TiO{sub 2}-NTs is more than 5 times higher than that of pure TiO{sub 2} NTs. Comparing with the electrochemical deposition method, the photocatalytic activity of Ag/TiO{sub 2}-NTs prepared by polyol method has been obviously increased.« less

  15. DISTRIBUTED RC NETWORKS WITH RATIONAL TRANSFER FUNCTIONS,

    DTIC Science & Technology

    A distributed RC circuit analogous to a continuously tapped transmission line can be made to have a rational short-circuit transfer admittance and...one rational shortcircuit driving-point admittance. A subcircuit of the same structure has a rational open circuit transfer impedance and one rational ...open circuit driving-point impedance. Hence, rational transfer functions may be obtained while considering either generator impedance or load

  16. CARRIER/CASK HANDLING SYSTEM DESCRIPTION DOCUMENT

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

    E.F. Loros

    2000-06-23

    The Carrier/Cask Handling System receives casks on railcars and legal-weight trucks (LWTs) (transporters) that transport loaded casks and empty overpacks to the Monitored Geologic Repository (MGR) from the Carrier/Cask Transport System. Casks that come to the MGR on heavy-haul trucks (HHTs) are transferred onto railcars before being brought into the Carrier/Cask Handling System. The system is the interfacing system between the railcars and LWTs and the Assembly Transfer System (ATS) and Canister Transfer System (CTS). The Carrier/Cask Handling System removes loaded casks from the cask transporters and transfers the casks to a transfer cart for either the ATS or CTS,more » as appropriate, based on cask contents. The Carrier/Cask Handling System receives the returned empty casks from the ATS and CTS and mounts the casks back onto the transporters for reshipment. If necessary, the Carrier/Cask Handling System can also mount loaded casks back onto the transporters and remove empty casks from the transporters. The Carrier/Cask Handling System receives overpacks from the ATS loaded with canisters that have been cut open and emptied and mounts the overpacks back onto the transporters for disposal. If necessary, the Carrier/Cask Handling System can also mount empty overpacks back onto the transporters and remove loaded overpacks from them. The Carrier/Cask Handling System is located within the Carrier Bay of the Waste Handling Building System. The system consists of cranes, hoists, manipulators, and supporting equipment. The Carrier/Cask Handling System is designed with the tooling and fixtures necessary for handling a variety of casks. The Carrier/Cask Handling System performance and reliability are sufficient to support the shipping and emplacement schedules for the MGR. The Carrier/Cask Handling System interfaces with the Carrier/Cask Transport System, ATS, and CTS as noted above. The Carrier/Cask Handling System interfaces with the Waste Handling Building System for building structures and space allocations. The Carrier/Cask Handling System interfaces with the Waste Handling Building Electrical System for electrical power.« less

  17. Stability analysis of electrical powered wheelchair-mounted robotic-assisted transfer device.

    PubMed

    Wang, Hongwu; Tsai, Chung-Ying; Jeannis, Hervens; Chung, Cheng-Shiu; Kelleher, Annmarie; Grindle, Garrett G; Cooper, Rory A

    2014-01-01

    The ability of people with disabilities to live in their homes and communities with maximal independence often hinges, at least in part, on their ability to transfer or be transferred by an assistant. Because of limited resources and the expense of personal care, robotic transfer assistance devices will likely be in great demand. An easy-to-use system for assisting with transfers, attachable to electrical powered wheelchairs (EPWs) and readily transportable, could have a significant positive effect on the quality of life of people with disabilities. We investigated the stability of our newly developed Strong Arm, which is attached and integrated with an EPW to assist with transfers. The stability of the system was analyzed and verified by experiments applying different loads and using different system configurations. The model predicted the distributions of the system's center of mass very well compared with the experimental results. When real transfers were conducted with 50 and 75 kg loads and an 83.25 kg dummy, the current Strong Arm could transfer all weights safely without tip-over. Our modeling accurately predicts the stability of the system and is suitable for developing better control algorithms to enhance the safety of the device.

  18. A Numerical Process Control Method for Circular-Tube Hydroforming Prediction

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

    Johnson, Kenneth I.; Nguyen, Ba Nghiep; Davies, Richard W.

    2004-03-01

    This paper describes the development of a solution control method that tracks the stresses, strains and mechanical behavior of a tube during hydroforming to estimate the proper axial feed (end-feed) and internal pressure loads through time. The analysis uses the deformation theory of plasticity and Hill?s criterion to describe the plastic flow. Before yielding, the pressure and end-feed increments are estimated based on the initial tube geometry, elastic properties and yield stress. After yielding, the pressure increment is calculated based on the tube geometry at the previous solution increment and the current hoop stress increment. The end-feed increment is computedmore » from the increment of the axial plastic strain. Limiting conditions such as column buckling (of long tubes), local axi-symmetric wrinkling of shorter tubes, and bursting due to localized wall thinning are considered. The process control method has been implemented in the Marc finite element code. Hydroforming simulations using this process control method were conducted to predict the load histories for controlled expansion of 6061-T4 aluminum tubes within a conical die shape and under free hydroforming conditions. The predicted loading paths were transferred to the hydroforming equipment to form the conical and free-formed tube shapes. The model predictions and experimental results are compared for deformed shape, strains and the extent of forming at rupture.« less

  19. Implementation and Assessment of Cognitive Load Theory (CLT) Based Questions in an Electronic Homework and Testing System

    ERIC Educational Resources Information Center

    Behmke, Derek A.; Atwood, Charles H.

    2013-01-01

    To a first approximation, human memory is divided into two parts, short-term and long-term. Cognitive Load Theory (CLT) attempts to minimize the short-term memory load while maximizing the memory available for transferring knowledge from short-term to long-term memory. According to CLT there are three types of load, intrinsic, extraneous, and…

  20. Low platinum loading for high temperature proton exchange membrane fuel cell developed by ultrasonic spray coating technique

    NASA Astrophysics Data System (ADS)

    Su, Huaneng; Jao, Ting-Chu; Barron, Olivia; Pollet, Bruno G.; Pasupathi, Sivakumar

    2014-12-01

    This paper reports use of an ultrasonic-spray for producing low Pt loadings membrane electrode assemblies (MEAs) with the catalyst coated substrate (CCS) fabrication technique. The main MEA sub-components (catalyst, membrane and gas diffusion layer (GDL)) are supplied from commercial manufacturers. In this study, high temperature (HT) MEAs with phosphoric acid (PA)-doped poly(2,5-benzimidazole) (AB-PBI) membrane are fabricated and tested under 160 °C, hydrogen and air feed 100 and 250 cc min-1 and ambient pressure conditions. Four different Pt loadings (from 0.138 to 1.208 mg cm-2) are investigated in this study. The experiment data are determined by in-situ electrochemical methods such as polarization curve, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The high Pt loading MEA exhibits higher performance at high voltage operating conditions but lower performances at peak power due to the poor mass transfer. The Pt loading 0.350 mg cm-2 GDE performs the peak power density and peak cathode mass power to 0.339 W cm-2 and 0.967 W mgPt-1, respectively. This work presents impressive cathode mass power and high fuel cell performance for high temperature proton exchange membrane fuel cells (HT-PEMFCs) with low Pt loadings.

  1. Estimation of Road Friction Coefficient in Different Road Conditions Based on Vehicle Braking Dynamics

    NASA Astrophysics Data System (ADS)

    Zhao, You-Qun; Li, Hai-Qing; Lin, Fen; Wang, Jian; Ji, Xue-Wu

    2017-07-01

    The accurate estimation of road friction coefficient in the active safety control system has become increasingly prominent. Most previous studies on road friction estimation have only used vehicle longitudinal or lateral dynamics and often ignored the load transfer, which tends to cause inaccurate of the actual road friction coefficient. A novel method considering load transfer of front and rear axles is proposed to estimate road friction coefficient based on braking dynamic model of two-wheeled vehicle. Sliding mode control technique is used to build the ideal braking torque controller, which control target is to control the actual wheel slip ratio of front and rear wheels tracking the ideal wheel slip ratio. In order to eliminate the chattering problem of the sliding mode controller, integral switching surface is used to design the sliding mode surface. A second order linear extended state observer is designed to observe road friction coefficient based on wheel speed and braking torque of front and rear wheels. The proposed road friction coefficient estimation schemes are evaluated by simulation in ADAMS/Car. The results show that the estimated values can well agree with the actual values in different road conditions. The observer can estimate road friction coefficient exactly in real-time and resist external disturbance. The proposed research provides a novel method to estimate road friction coefficient with strong robustness and more accurate.

  2. London University Search Instrument: a combinatorial robot for high-throughput methods in ceramic science.

    PubMed

    Wang, Jian; Evans, Julian R G

    2005-01-01

    This paper describes the design, construction, and operation of the London University Search Instrument (LUSI) which was recently commissioned to create and test combinatorial libraries of ceramic compositions. The instrument uses commercially available powders, milled as necessary to create thick-film libraries by ink-jet printing. Multicomponent mixtures are prepared by well plate reformatting of ceramic inks. The library tiles are robotically loaded into a flatbed furnace and, when fired, transferred to a 2-axis high-resolution measurement table fitted with a hot plate where measurements of, for example, optical or electrical properties can be made. Data are transferred to a dedicated high-performance computer. The possibilities for remote interrogation and search steering are discussed.

  3. Tendon transfer fixation: comparing a tendon to tendon technique vs. bioabsorbable interference-fit screw fixation.

    PubMed

    Sabonghy, Eric Peter; Wood, Robert Michael; Ambrose, Catherine Glauber; McGarvey, William Christopher; Clanton, Thomas Oscar

    2003-03-01

    Tendon transfer techniques in the foot and ankle are used for tendon ruptures, deformities, and instabilities. This fresh cadaver study compares the tendon fixation strength in 10 paired specimens by performing a tendon to tendon fixation technique or using 7 x 20-25 mm bioabsorbable interference-fit screw tendon fixation technique. Load at failure of the tendon to tendon fixation method averaged 279N (Standard Deviation 81N) and the bioabsorbable screw 148N (Standard Deviation 72N) [p = 0.0008]. Bioabsorbable interference-fit screws in these specimens show decreased fixation strength relative to the traditional fixation technique. However, the mean bioabsorbable screw fixation strength of 148N provides physiologic strength at the tendon-bone interface.

  4. Hydrogen Maser Clocks in Space for Solid-Earth Research and Time-Transfer Applications: Experiment Overview and Evaluation of Russian Miniature Sapphire Loaded Cavity,

    DTIC Science & Technology

    cavity, a technique pioneered at VNIIFTRI . Various contacts between West-European parties, headed by ESA, and the Russian parties, headed by RSA, Led...provided by ON and the other by VNIIFTRI . T/F transfer and precise positioning will be performed by both a microwave link, using PRARE equipment, and...sapphire loaded microwave cavity, on Loan from VNIIFTRI , was evaluated in a full-size EFOS hydrogen maser built by ON. The experimental evaluation

  5. Transfer Relation between the Compression Test Rig and the Anthropomorphic Test Device (ATD) Lower Leg

    DTIC Science & Technology

    2015-08-01

    2 Fig. 3 FEA model for the ATD lower-leg loading...3 Fig. 4 Typical pressure distribution under the boot sole in the FEA result ................................ 4 Fig. 5 Load histories of...the ATD lower leg in 10-meter-per-second (m/s), 10-millisecond (msec) pulse loading FEA

  6. Controllable load sharing for soft adhesive interfaces on three-dimensional surfaces.

    PubMed

    Song, Sukho; Drotlef, Dirk-Michael; Majidi, Carmel; Sitti, Metin

    2017-05-30

    For adhering to three-dimensional (3D) surfaces or objects, current adhesion systems are limited by a fundamental trade-off between 3D surface conformability and high adhesion strength. This limitation arises from the need for a soft, mechanically compliant interface, which enables conformability to nonflat and irregularly shaped surfaces but significantly reduces the interfacial fracture strength. In this work, we overcome this trade-off with an adhesion-based soft-gripping system that exhibits enhanced fracture strength without sacrificing conformability to nonplanar 3D surfaces. Composed of a gecko-inspired elastomeric microfibrillar adhesive membrane supported by a pressure-controlled deformable gripper body, the proposed soft-gripping system controls the bonding strength by changing its internal pressure and exploiting the mechanics of interfacial equal load sharing. The soft adhesion system can use up to ∼26% of the maximum adhesion of the fibrillar membrane, which is 14× higher than the adhering membrane without load sharing. Our proposed load-sharing method suggests a paradigm for soft adhesion-based gripping and transfer-printing systems that achieves area scaling similar to that of a natural gecko footpad.

  7. Controllable load sharing for soft adhesive interfaces on three-dimensional surfaces

    NASA Astrophysics Data System (ADS)

    Song, Sukho; Drotlef, Dirk-Michael; Majidi, Carmel; Sitti, Metin

    2017-05-01

    For adhering to three-dimensional (3D) surfaces or objects, current adhesion systems are limited by a fundamental trade-off between 3D surface conformability and high adhesion strength. This limitation arises from the need for a soft, mechanically compliant interface, which enables conformability to nonflat and irregularly shaped surfaces but significantly reduces the interfacial fracture strength. In this work, we overcome this trade-off with an adhesion-based soft-gripping system that exhibits enhanced fracture strength without sacrificing conformability to nonplanar 3D surfaces. Composed of a gecko-inspired elastomeric microfibrillar adhesive membrane supported by a pressure-controlled deformable gripper body, the proposed soft-gripping system controls the bonding strength by changing its internal pressure and exploiting the mechanics of interfacial equal load sharing. The soft adhesion system can use up to ˜26% of the maximum adhesion of the fibrillar membrane, which is 14× higher than the adhering membrane without load sharing. Our proposed load-sharing method suggests a paradigm for soft adhesion-based gripping and transfer-printing systems that achieves area scaling similar to that of a natural gecko footpad.

  8. Controllable load sharing for soft adhesive interfaces on three-dimensional surfaces

    PubMed Central

    Song, Sukho; Drotlef, Dirk-Michael; Majidi, Carmel; Sitti, Metin

    2017-01-01

    For adhering to three-dimensional (3D) surfaces or objects, current adhesion systems are limited by a fundamental trade-off between 3D surface conformability and high adhesion strength. This limitation arises from the need for a soft, mechanically compliant interface, which enables conformability to nonflat and irregularly shaped surfaces but significantly reduces the interfacial fracture strength. In this work, we overcome this trade-off with an adhesion-based soft-gripping system that exhibits enhanced fracture strength without sacrificing conformability to nonplanar 3D surfaces. Composed of a gecko-inspired elastomeric microfibrillar adhesive membrane supported by a pressure-controlled deformable gripper body, the proposed soft-gripping system controls the bonding strength by changing its internal pressure and exploiting the mechanics of interfacial equal load sharing. The soft adhesion system can use up to ∼26% of the maximum adhesion of the fibrillar membrane, which is 14× higher than the adhering membrane without load sharing. Our proposed load-sharing method suggests a paradigm for soft adhesion-based gripping and transfer-printing systems that achieves area scaling similar to that of a natural gecko footpad. PMID:28507143

  9. Allowable compressive stress at prestress transfer.

    DOT National Transportation Integrated Search

    2008-12-01

    In 2004, The Texas Department of Transportation initiated Project 5197 to investigate the feasibility of : increasing the allowable compressive stress limit at prestress transfer. Initially, the live load performance of 36 : specimens was evaluated b...

  10. Heat transfer coefficient as parameter describing ability of insulating liquid to heat transfer

    NASA Astrophysics Data System (ADS)

    Nadolny, Zbigniew; Gościński, Przemysław; Bródka, Bolesław

    2017-10-01

    The paper presents the results of the measurements of heat transfer coefficient of insulating liquids used in transformers. The coefficient describes an ability of the liquid to heat transport. On the basis of the coefficient, effectiveness of cooling system of electric power devices can be estimated. Following liquids were used for the measurements: mineral oil, synthetic ester and natural ester. It was assumed that surface heat load is about 2500 W·m-2, which is equal the load of transformer windings. A height of heat element was 1.6 m, because it makes possible steady distribution of temperature on its surface. The measurements of heat transfer coefficient was made as a function of various position of heat element (vertical, horizontal). In frame of horizontal position of heat element, three suppositions were analysed: top, bottom, and side.

  11. Sound-Intensity Feedback During Running Reduces Loading Rates and Impact Peak.

    PubMed

    Tate, Jeremiah J; Milner, Clare E

    2017-08-01

    Study Design Controlled laboratory study, within-session design. Background Gait retraining has been proposed as an effective intervention to reduce impact loading in runners at risk of stress fractures. Interventions that can be easily implemented in the clinic are needed. Objective To assess the immediate effects of sound-intensity feedback related to impact during running on vertical impact peak, peak vertical instantaneous loading rate, and vertical average loading rate. Methods Fourteen healthy, college-aged runners who ran at least 9.7 km/wk participated (4 male, 10 female; mean ± SD age, 23.7 ± 2.0 years; height, 1.67 ± 0.08 m; mass, 60.9 ± 8.7 kg). A decibel meter provided real-time sound-intensity feedback of treadmill running via an iPad application. Participants were asked to reduce the sound intensity of running while receiving continuous feedback for 15 minutes, while running at their self-selected preferred speed. Baseline and follow-up ground reaction force data were collected during overground running at participants' self-selected preferred running speed. Results Dependent t tests indicated a statistically significant reduction in vertical impact peak (1.56 BW to 1.13 BW, P≤.001), vertical instantaneous loading rate (95.48 BW/s to 62.79 BW/s, P = .001), and vertical average loading rate (69.09 BW/s to 43.91 BW/s, P≤.001) after gait retraining, compared to baseline. Conclusion The results of the current study support the use of sound-intensity feedback during treadmill running to immediately reduce loading rate and impact force. The transfer of within-session reductions in impact peak and loading rates to overground running was demonstrated. Decreases in loading were of comparable magnitude to those observed in other gait retraining methods. J Orthop Sports Phys Ther 2017;47(8):565-569. Epub 6 Jul 2017. doi:10.2519/jospt.2017.7275.

  12. Pulse mitigation and heat transfer enhancement techniques. Volume 3: Liquid sodium heat transfer facility and transient response of sodium heat pipe to pulse forward and reverse heat load

    NASA Astrophysics Data System (ADS)

    Chow, L. C.; Hahn, O. J.; Nguyen, H. X.

    1992-08-01

    This report presents the description of a liquid sodium heat transfer facility (sodium loop) constructed to support the study of transient response of heat pipes. The facility, consisting of the loop itself, a safety system, and a data acquisition system, can be safely operated over a wide range of temperature and sodium flow rate. The transient response of a heat pipe to pulse heat load at the condenser section was experimentally investigated. A 0.457 m screen wick, sodium heat pipe with an outer diameter of 0.127 m was tested under different heat loading conditions. A major finding was that the heat pipe reversed under a pulse heat load applied at the condenser. The time of reversal was approximately 15 to 25 seconds. The startup of the heat pipe from frozen state was also studied. It was found that during the startup process, at least part of the heat pipe was active. The active region extended gradually down to the end of the condenser until all of the working fluid in the heat pipe was molten.

  13. Micro-mechanical damage of trabecular bone-cement interface under selected loading conditions: a finite element study.

    PubMed

    Zhang, Qing-Hang; Tozzi, Gianluca; Tong, Jie

    2014-01-01

    In this study, two micro finite element models of trabecular bone-cement interface developed from high resolution computed tomography (CT) images were loaded under compression and validated using the in situ experimental data. The models were then used under tension and shear to examine the load transfer between the bone and cement and the micro damage development at the bone-cement interface. In addition, one models was further modified to investigate the effect of cement penetration on the bone-cement interfacial behaviour. The simulated results show that the load transfer at the bone-cement interface occurred mainly in the bone cement partially interdigitated region, while the fully interdigitated region seemed to contribute little to the mechanical response. Consequently, cement penetration beyond a certain value would seem to be ineffective in improving the mechanical strength of trabecular bone-cement interface. Under tension and shear loading conditions, more cement failures were found in denser bones, while the cement damage is generally low under compression.

  14. Crack growth induced by thermal-mechanical loading

    NASA Astrophysics Data System (ADS)

    John, R.; Hartman, G. A.; Gallagher, J. P.

    1992-06-01

    Advanced aerospace structures are often subjected to combined thermal and mechanical loads. The fracture-mechanics behavior of the structures may be altered by the thermal state existing around the crack. Hence, design of critical structural elements requires the knowledge of stress-intensity factors under both thermal and mechanical loads. This paper describes the development of an experimental technique to verify the thermal-stress-intensity factor generated by a temperature gradient around the crack. Thin plate specimens of a model material (AISI-SAE 1095 steel) were used for the heat transfer and thermal-mechanical fracture tests. Rapid thermal loading was achieved using high-intensity focused infrared spot heaters. These heaters were also used to generate controlled temperature rates for heat-transfer verification tests. The experimental results indicate that thermal loads can generate stress-intensity factors large enough to induce crack growth. The proposed thermal-stress-intensity factors appear to have the same effect as the conventional mechanical-stress-intensity factors with respect to fracture.

  15. Large scale commissioning and operational experience with tier-2 to tier-2 data transfer links in CMS

    NASA Astrophysics Data System (ADS)

    Letts, J.; Magini, N.

    2011-12-01

    Tier-2 to Tier-2 data transfers have been identified as a necessary extension of the CMS computing model. The Debugging Data Transfers (DDT) Task Force in CMS was charged with commissioning Tier-2 to Tier-2 PhEDEx transfer links beginning in late 2009, originally to serve the needs of physics analysis groups for the transfer of their results between the storage elements of the Tier-2 sites associated with the groups. PhEDEx is the data transfer middleware of the CMS experiment. For analysis jobs using CRAB, the CMS Remote Analysis Builder, the challenges of remote stage out of job output at the end of the analysis jobs led to the introduction of a local fallback stage out, and will eventually require the asynchronous transfer of user data over essentially all of the Tier-2 to Tier-2 network using the same PhEDEx infrastructure. In addition, direct file sharing of physics and Monte Carlo simulated data between Tier-2 sites can relieve the operational load of the Tier-1 sites in the original CMS Computing Model, and already represents an important component of CMS PhEDEx data transfer volume. The experience, challenges and methods used to debug and commission the thousands of data transfers links between CMS Tier-2 sites world-wide are explained and summarized. The resulting operational experience with Tier-2 to Tier-2 transfers is also presented.

  16. Biodynamic feedback training to assure learning partial load bearing on forearm crutches.

    PubMed

    Krause, Daniel; Wünnemann, Martin; Erlmann, Andre; Hölzchen, Timo; Mull, Melanie; Olivier, Norbert; Jöllenbeck, Thomas

    2007-07-01

    To examine how biodynamic feedback training affects the learning of prescribed partial load bearing (200N). Three pre-post experiments. Biomechanics laboratory in a German university. A volunteer sample of 98 uninjured subjects who had not used crutches recently. There were 24 subjects in experiment 1 (mean age, 23.2y); 64 in experiment 2 (mean age, 43.6y); and 10 in experiment 3 (mean age, 40.3y), parallelized by arm force. Video instruction and feedback training: In experiment 1, 2 varied instruction videos and reduced feedback frequency; in experiment 2, varied frequencies of changing tasks (contextual interference); and in experiment 3, feedback training (walking) and transfer (stair tasks). Vertical ground reaction force. Absolute error of practiced tasks was significantly reduced for all samples (P<.050). Varied contextual interference conditions did not significantly affect retention (P=.798) or transfer (P=.897). Positive transfer between tasks was significant in experiment 2 (P<.001) and was contrary to findings in experiment 3 (P=.071). Biodynamic feedback training is applicable for learning prescribed partial load bearing. The frequency of changing tasks is irrelevant. Despite some support for transfer effects, additional practice in climbing and descending stairs might be beneficial.

  17. Simultaneous determination of aflatoxin B₁, B₂, G₁, and G₂ in corn powder, edible oil, peanut butter, and soy sauce by liquid chromatography with tandem mass spectrometry utilizing turbulent flow chromatography.

    PubMed

    Fan, Sufang; Li, Qiang; Zhang, Xiaoguang; Cui, Xiaobin; Zhang, Dongsheng; Zhang, Yan

    2015-05-01

    A novel fully automated method based on dual column switching using turbulent flow chromatography followed by liquid chromatography with tandem mass spectrometry was developed for the determination of aflatoxin B1 , B2 , G1 , and G2 in corn powder, edible oil, peanut butter, and soy sauce samples. After ultrasound-assisted extraction, samples were directly injected to the chromatographic system and the analytes were concentrated into the clean-up loading column. Through purge switching, the analytes were transferred to the analytical column for subsequent detection by mass spectrometry. Different types of TurboFlow(TM) columns, transfer flow rate, transfer time were optimized. The limits of detection and quantification of this method ranged between 0.2-2.0 and 0.5-4.0 μg/kg for aflatoxins in different matrixes, respectively. Recoveries of aflatoxins were in range of 83-108.1% for all samples, matrix effects were in range of 34.1-104.7%. The developed method has been successfully applied in the analysis of aflatoxin B1 , B2 , G1 , and G2 in real samples. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Time-Variant Reliability Analysis for Rubber O-Ring Seal Considering Both Material Degradation and Random Load

    PubMed Central

    Liao, Baopeng; Yan, Meichen; Zhang, Weifang; Zhou, Kun

    2017-01-01

    Due to the increase in working hours, the reliability of rubber O-ring seals used in hydraulic systems of transfer machines will change. While traditional methods can only analyze one of the material properties or seal properties, the failure of the O-ring is caused by these two factors together. In this paper, two factors are mainly analyzed: the degradation of material properties and load randomization by processing technology. Firstly, the two factors are defined in terms of material failure and seal failure, before the experimental methods of rubber materials are studied. Following this, the time-variant material properties through experiments and load distribution by monitoring the processing can be obtained. Thirdly, compressive stress and contact stress have been calculated, which was combined with the reliability model to acquire the time-variant reliability for the O-ring. Finally, the life prediction and effect of oil pressure were discussed, then compared with the actual situation. The results show a lifetime of 12 months for the O-ring calculated in this paper, and compared with the replacement records from the maintenance workshop, the result is credible. PMID:29053597

  19. Spent nuclear fuel dry transfer system

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

    Stewart, L.; Agace, S.

    The U.S. Department of Energy is currently engaged in a cooperative program with the Electric Power Research Institute (EPRI) to design a spent nuclear fuel dry transfer system (DTS). The system will enable the transfer of individual spent nuclear fuel assemblies between a conventional top loading cask and multi-purpose canister in a shielded overpack, or accommodate spent nuclear fuel transfers between two conventional casks.

  20. The mechanism of bolt loading

    NASA Technical Reports Server (NTRS)

    Lee, H. M.

    1992-01-01

    It is shown that the mechanism of bolt loading for preloaded fasteners can be effectively portrayed through simple spring models and some algebraic manipulations. Understanding schematically what is involved in such joints provides insight into the distribution of loads. The developed equations confirm that for both symmetric and nonsymmetric joints the loading plane factor and the stiffness factor directly affect the load seen in preloaded fasteners. The manner in which an external loading is transferred through the joint can be explained as energy dissipated in the various springs of both the abutment and the bolt itself.

  1. 15-month-olds' transfer of learning between touch screen and real-world displays: language cues and cognitive loads.

    PubMed

    Zack, Elizabeth; Gerhardstein, Peter; Meltzoff, Andrew N; Barr, Rachel

    2013-02-01

    Infants have difficulty transferring information between 2D and 3D sources. The current study extends Zack, Barr, Gerhardstein, Dickerson & Meltzoff's (2009) touch screen imitation task to examine whether the addition of specific language cues significantly facilitates 15-month-olds' transfer of learning between touch screens and real-world 3D objects. The addition of two kinds of linguistic cues (object label plus verb or nonsense name) did not elevate action imitation significantly above levels observed when such language cues were not used. Language cues hindered infants' performance in the 3D→2D direction of transfer, but only for the object label plus verb condition. The lack of a facilitative effect of language is discussed in terms of competing cognitive loads imposed by conjointly transferring information across dimensions and processing linguistic cues in an action imitation task at this age. © 2012 The Authors. Scandinavian Journal of Psychology © 2012 The Scandinavian Psychological Associations.

  2. A Research Program for Improving Heat Transfer Prediction Capability for the Laminar to Turbulent Transition Region of Turbine Vanes/Blades

    NASA Technical Reports Server (NTRS)

    Simon, Frederick F.

    2007-01-01

    A program sponsored by the National Aeronautics and Space Administration (NASA) for the investigation of the heat transfer in the transition region of turbine vanes and blades with the object of improving the capability for predicting heat transfer is described,. The accurate prediction of gas-side heat transfer is important to the determination of turbine longevity, engine performance and developmental costs. The need for accurate predictions will become greater as the operating temperatures and stage loading levels of advanced turbine engines increase. The present methods for predicting transition shear stress and heat transfer on turbine blades are based on incomplete knowledge and are largely empirical. To meet the objectives of the NASA program, a team approach consisting of researchers from government, universities, a research institute, and a small business is presented. The research is divided into areas of experimentation, direct numerical simulation (DNS) and turbulence modeling. A summary of the results to date is given for the above research areas in a high-disturbance environment (bypass transition) with a discussion of the model development necessary for use in numerical codes.

  3. Methods for heat transfer and temperature field analysis of the insulated diesel phase 2 progress report

    NASA Technical Reports Server (NTRS)

    Morel, T.; Kerlbar, R.; Fort, E. F.; Blumberg, P. N.

    1985-01-01

    This report describes work done during Phase 2 of a 3 year program aimed at developing a comprehensive heat transfer and thermal analysis methodology for design analysis of insulated diesel engines. The overall program addresses all the key heat transfer issues: (1) spatially and time-resolved convective and radiative in-cylinder heat transfer, (2) steady-state conduction in the overall structure, and (3) cyclical and load/speed temperature transients in the engine structure. During Phase 2, radiation heat transfer model was developed, which accounts for soot formation and burn up. A methodology was developed for carrying out the multi-dimensional finite-element heat conduction calculations within the framework of thermodynamic cycle codes. Studies were carried out using the integrated methodology to address key issues in low heat rejection engines. A wide ranging design analysis matrix was covered, including a variety of insulation strategies, recovery devices and base engine configurations. A single cylinder Cummins engine was installed at Purdue University, and it was brought to a full operational status. The development of instrumentation was continued, concentrating on radiation heat flux detector, total heat flux probe, and accurate pressure-crank angle data acquisition.

  4. High-power piezoelectric acoustic-electric power feedthru for metal walls

    NASA Astrophysics Data System (ADS)

    Bao, Xiaoqi; Biederman, Will; Sherrit, Stewart; Badescu, Mircea; Bar-Cohen, Yoseph; Jones, Christopher; Aldrich, Jack; Chang, Zensheu

    2008-03-01

    Piezoelectric acoustic-electric power feed-through devices transfer electric power wirelessly through a solid wall using elastic waves. This approach allows for the elimination of the need for holes through structures for cabling or electrical feed-thrus . The technology supplies power to electric equipment inside sealed containers, vacuum or pressure vessels, etc where holes in the wall are prohibitive or may result in significant performance degradation or requires complex designs. In the our previous work, 100-W of electric power was transferred through a metal wall by a small, piezoelectric device with a simple-structure. To meet requirements of higher power applications, the feasibility to transfer kilowatts level power was investigated. Pre-stressed longitudinal piezoelectric feed-thru devices were analyzed by finite element modeling. An equivalent circuit model was developed to predict the characteristics of power transfer to different electric loads. Based on the analytical results, a prototype device was designed, fabricated and successfully demonstrated to transfer electric power at a level of 1-kW. Methods of minimizing plate wave excitation on the wall were also analyzed. Both model analysis and experimental results are presented in detail in this paper.

  5. Thermo-compressive transfer printing for facile alignment and robust device integration of nanowires.

    PubMed

    Lee, Won Seok; Won, Sejeong; Park, Jeunghee; Lee, Jihye; Park, Inkyu

    2012-06-07

    Controlled alignment and mechanically robust bonding between nanowires (NWs) and electrodes are essential requirements for reliable operation of functional NW-based electronic devices. In this work, we developed a novel process for the alignment and bonding between NWs and metal electrodes by using thermo-compressive transfer printing. In this process, bottom-up synthesized NWs were aligned in parallel by shear loading onto the intermediate substrate and then finally transferred onto the target substrate with low melting temperature metal electrodes. In particular, multi-layer (e.g. Cr/Au/In/Au and Cr/Cu/In/Au) metal electrodes are softened at low temperatures (below 100 °C) and facilitate submergence of aligned NWs into the surface of electrodes at a moderate pressure (∼5 bar). By using this thermo-compressive transfer printing process, robust electrical and mechanical contact between NWs and metal electrodes can be realized. This method is believed to be very useful for the large-area fabrication of NW-based electrical devices with improved mechanical robustness, electrical contact resistance, and reliability.

  6. High-Power Piezoelectric Acoustic-Electric Power Feedthru for Metal Walls

    NASA Technical Reports Server (NTRS)

    Bao, Xiaoqi; Biederman, Will; Sherrit, Stewart; Badescu, Mircea; Bar-Cohen, Yoseph; Jones, Christopher; Aldrich, Jack; Chang, Zensheu

    2008-01-01

    Piezoelectric acoustic-electric power feed-through devices transfer electric power wirelessly through a solid wall by using acoustic waves. This approach allows for the removal of holes through structures. The technology is applicable to power supply for electric equipment inside sealed containers, vacuum or pressure vessels, etc where the holes on the wall are prohibitive or result in significant performance degrade or complex designs. In the author's previous work, 100-W electric power was transferred through a metal wall by a small, simple-structure piezoelectric device. To meet requirements of higher power applications, the feasibility to transfer kilowatts level power was investigated. Pre-stressed longitudinal piezoelectric feedthru devices were analyzed by finite element model. An equivalent circuit model was developed to predict the power transfer characteristics to different electric loads. Based on the analysis results, a prototype device was designed, fabricated and a demonstration of the transmission of electric power up to 1-kW was successfully conducted. The methods to minimize the plate wave excitation on the wall were also analyzed. Both model analysis and experimental results are presented in detail in this presentation.

  7. A methodology to model physical contact between structural components in NASTRAN

    NASA Technical Reports Server (NTRS)

    Prabhu, Annappa A.

    1993-01-01

    Two components of a structure which are located side by side, will come in contact by certain force and will transfer the compressive force along the contact area. If the force acts in the opposite direction, the elements will separate and no force will be transferred. If this contact is modeled, the load path will be correctly represented, and the load redistribution results in more realistic stresses in the structure. This is accomplished by using different sets of rigid elements for different loading conditions, or by creating multipoint constraint sets. Comparison of these two procedures is presented for a 4 panel unit (PU) stowage drawer installed in an experiment rack in the Spacelab Life Sciences (SLS-2) payload.

  8. Transfer-arm evaporator cell for rapid loading and deposition of organic thin films.

    PubMed

    Greiner, M T; Helander, M G; Wang, Z B; Lu, Z H

    2009-12-01

    Described herein is a transfer-arm evaporator cell (TAE-cell), which allows for rapid loading of materials into vacuum for low-temperature sublimation deposition of thin films. This design can be incorporated with an existing analysis system for convenient in situ thin film characterization. This evaporator is especially well suited for photoemission characterization of organic semiconductor interfaces. Photoemission is one of the most important techniques for characterizing such, however, it generally requires in situ sample preparation. The ease with which materials can be loaded and evaporated with this design increases the throughput of in situ photoemission characterization, and broadens the research scope of the technique. Here, we describe the design, operation, and performance of the TAE-cell.

  9. 33 CFR 127.1102 - Transfer hoses and loading arms.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... transferred, in both the liquid and vapor state (if wire braid is used for reinforcement, the wire must be of corrosion-resistant material, such as stainless steel); (2) Be constructed to withstand the temperature and...

  10. 33 CFR 127.1102 - Transfer hoses and loading arms.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... transferred, in both the liquid and vapor state (if wire braid is used for reinforcement, the wire must be of corrosion-resistant material, such as stainless steel); (2) Be constructed to withstand the temperature and...

  11. Regulation control and energy management scheme for wireless power transfer

    DOEpatents

    Miller, John M.

    2015-12-29

    Power transfer rate at a charging facility can be maximized by employing a feedback scheme. The state of charge (SOC) and temperature of the regenerative energy storage system (RESS) pack of a vehicle is monitored to determine the load due to the RESS pack. An optimal frequency that cancels the imaginary component of the input impedance for the output signal from a grid converter is calculated from the load of the RESS pack, and a frequency offset f* is made to the nominal frequency f.sub.0 of the grid converter output based on the resonance frequency of a magnetically coupled circuit. The optimal frequency can maximize the efficiency of the power transfer. Further, an optimal grid converter duty ratio d* can be derived from the charge rate of the RESS pack. The grid converter duty ratio d* regulates wireless power transfer (WPT) power level.

  12. Infrared thermography with non-uniform heat flux boundary conditions on the rotor endwall of an axial turbine

    NASA Astrophysics Data System (ADS)

    Lazzi Gazzini, S.; Schädler, R.; Kalfas, A. I.; Abhari, R. S.

    2017-02-01

    It is technically challenging to measure heat fluxes on the rotating components of gas turbines, yet accurate knowledge of local heat loads under engine-representative conditions is crucial for ensuring the reliability of the designs. In this work, quantitative image processing tools were developed to perform fast and accurate infrared thermography measurements on 3D-shaped film-heaters directly deposited on the turbine endwalls. The newly developed image processing method and instrumentation were used to measure the heat load on the rotor endwalls of an axial turbine. A step-transient heat flux calibration technique is applied to measure the heat flux generated locally by the film heater, thus eliminating the need for a rigorously iso-energetic boundary condition. On-board electronics installed on the rotor record the temperature readings of RTDs installed in the substrate below the heaters in order to evaluate the conductive losses in the solid. Full maps of heat transfer coefficient and adiabatic wall temperature are produced for two different operating conditions, demonstrating the sensitivity of the technique to local flow features and variations in heat transfer due to Reynolds number effect.

  13. Consideration of impedance matching techniques for efficient piezoelectric energy harvesting.

    PubMed

    Kim, Hyeoungwoo; Priya, Shashank; Stephanou, Harry; Uchino, Kenji

    2007-09-01

    This study investigates multiple levels of impedance-matching methods for piezoelectric energy harvesting in order to enhance the conversion of mechanical to electrical energy. First, the transduction rate was improved by using a high piezoelectric voltage constant (g) ceramic material having a magnitude of g33 = 40 x 10(-3) V m/N. Second, a transducer structure, cymbal, was optimized and fabricated to match the mechanical impedance of vibration source to that of the piezoelectric transducer. The cymbal transducer was found to exhibit approximately 40 times higher effective strain coefficient than the piezoelectric ceramics. Third, the electrical impedance matching for the energy harvesting circuit was considered to allow the transfer of generated power to a storage media. It was found that, by using the 10-layer ceramics instead of the single layer, the output current can be increased by 10 times, and the output load can be reduced by 40 times. Furthermore, by using the multilayer ceramics the output power was found to increase by 100%. A direct current (DC)-DC buck converter was fabricated to transfer the accumulated electrical energy in a capacitor to a lower output load. The converter was optimized such that it required less than 5 mW for operation.

  14. Evaluation of empirical rule of linearly correlated peptide selection (ERLPS) for proteotypic peptide-based quantitative proteomics.

    PubMed

    Liu, Kehui; Zhang, Jiyang; Fu, Bin; Xie, Hongwei; Wang, Yingchun; Qian, Xiaohong

    2014-07-01

    Precise protein quantification is essential in comparative proteomics. Currently, quantification bias is inevitable when using proteotypic peptide-based quantitative proteomics strategy for the differences in peptides measurability. To improve quantification accuracy, we proposed an "empirical rule for linearly correlated peptide selection (ERLPS)" in quantitative proteomics in our previous work. However, a systematic evaluation on general application of ERLPS in quantitative proteomics under diverse experimental conditions needs to be conducted. In this study, the practice workflow of ERLPS was explicitly illustrated; different experimental variables, such as, different MS systems, sample complexities, sample preparations, elution gradients, matrix effects, loading amounts, and other factors were comprehensively investigated to evaluate the applicability, reproducibility, and transferability of ERPLS. The results demonstrated that ERLPS was highly reproducible and transferable within appropriate loading amounts and linearly correlated response peptides should be selected for each specific experiment. ERLPS was used to proteome samples from yeast to mouse and human, and in quantitative methods from label-free to O18/O16-labeled and SILAC analysis, and enabled accurate measurements for all proteotypic peptide-based quantitative proteomics over a large dynamic range. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Structural Element Tests in Support of the Keyworker Blast Shelter Program

    DTIC Science & Technology

    1985-10-01

    forced concrete -lab with two transverse reinforced concrete floor beams to transfer the interior column loads to the floor slab. Using a roof slab... lateral buck- "-4 ling; however, this could have occurred after a column buckled and the roof collapsed. Since load cell 2 (middle column ) recorded the...ANALYSIS OF FREE-FIELD AND STRUCTURE LOADING DATA ... ........ .. 102 6.1.1 Loading Wave Velocity ........... .................... ... 102 6.1.2 Lateral

  16. Fracture Mechanical Analysis of Open Cell Ceramic Foams Under Thermal Shock Loading

    NASA Astrophysics Data System (ADS)

    Settgast, C.; Abendroth, M.; Kuna, M.

    2016-11-01

    Ceramic foams made by replica techniques containing sharp-edged cavities, which are potential crack initiators and therefore have to be analyzed using fracture mechanical methods. The ceramic foams made of novel carbon bonded alumina are used as filters in metal melt filtration applications, where the filters are exposed to a thermal shock. During the casting process the filters experience a complex thermo-mechanical loading, which is difficult to measure. Modern numerical methods allow the simulation of such complex processes. As a simplified foam structure an open Kelvin cell is used as a representative volume element. A three-dimensional finite element model containing realistic sharp-edged cavities and three-dimensional sub-models along these sharp edges are used to compute the transient temperature, stress and strain fields at the Kelvin foam. The sharp edges are evaluated using fracture mechanical methods like the J-integral technique. The results of this study describe the influence of the pore size, relative density of the ceramic foam, the heat transfer and selected material parameters on the fracture mechanical behaviour.

  17. TiO2 film/Cu2O microgrid heterojunction with photocatalytic activity under solar light irradiation.

    PubMed

    Zhang, Junying; Zhu, Hailing; Zheng, Shukai; Pan, Feng; Wang, Tianmin

    2009-10-01

    Coupling a narrow-band-gap semiconductor with TiO(2) is an effective method to produce photocatalysts that work under UV-vis light irradiation. Usually photocatalytic coupled-semiconductors exist mainly as powders, and photocatalytic activity is only favored when a small loading amount of narrow-band-gap semiconductor is used. Here we propose a heavy-loading photocatalyst configuration in which 51% of the surface of the TiO(2) film is covered by a Cu(2)O microgrid. The coupled system shows higher photocatalytic activity under solar light irradiation than TiO(2) and Cu(2)O films. This improved performance is due to the efficient charge transfer between the two phases and the similar opportunity each has to be exposed to irradiation and adsorbates.

  18. 9. LOADED CAR FLOAT AND TUG IN THE PROCESS OF ...

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

    9. LOADED CAR FLOAT AND TUG IN THE PROCESS OF DOCKING AT BRIDGE NO. 11. LOOKING EAST. - Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, Upper New York Bay, Jersey City, Hudson County, NJ

  19. RF power recovery feedback circulator

    DOEpatents

    Sharamentov, Sergey I [Bolingbrook, IL

    2011-03-29

    A device and method for improving the efficiency of RF systems having a Reflective Load. In the preferred embodiment, Reflected Energy from a superconducting resonator of a particle accelerator is reintroduced to the resonator after the phase of the Reflected Energy is aligned with the phase of the Supply Energy from a RF Energy Source. In one embodiment, a Circulator is used to transfer Reflected Energy from the Reflective Load into a Phase Adjuster which aligns the phase of the Reflected Energy with that of the Supply Energy. The phase-aligned energy is then combined with the Supply Energy, and reintroduced into the Reflective Load. In systems having a constant phase shift, the Phase Adjuster may be designed to shift the phase of the Reflected Energy by a constant amount using a Phase Shifter. In systems having a variety (variable) phase shifts, a Phase Shifter controlled by a phase feedback loop comprising a Phase Detector and a Feedback Controller to account for the various phase shifts is preferable.

  20. Biomechanics and Mechanobiology of Trabecular Bone: A Review

    PubMed Central

    Oftadeh, Ramin; Perez-Viloria, Miguel; Villa-Camacho, Juan C.; Vaziri, Ashkan; Nazarian, Ara

    2015-01-01

    Trabecular bone is a highly porous, heterogeneous, and anisotropic material which can be found at the epiphyses of long bones and in the vertebral bodies. Studying the mechanical properties of trabecular bone is important, since trabecular bone is the main load bearing bone in vertebral bodies and also transfers the load from joints to the compact bone of the cortex of long bones. This review article highlights the high dependency of the mechanical properties of trabecular bone on species, age, anatomic site, loading direction, and size of the sample under consideration. In recent years, high resolution micro finite element methods have been extensively used to specifically address the mechanical properties of the trabecular bone and provide unique tools to interpret and model the mechanical testing experiments. The aims of the current work are to first review the mechanobiology of trabecular bone and then present classical and new approaches for modeling and analyzing the trabecular bone microstructure and macrostructure and corresponding mechanical properties such as elastic properties and strength. PMID:25412137

  1. Pullout Performances of Grouted Rockbolt Systems with Bond Defects

    NASA Astrophysics Data System (ADS)

    Xu, Chang; Li, Zihan; Wang, Shanyong; Wang, Shuren; Fu, Lei; Tang, Chunan

    2018-03-01

    This paper presents a numerical study on the pullout behaviour of fully grouted rockbolts with bond defects. The cohesive zone model (CZM) is adopted to model the bond-slip behaviour between the rockbolt and grout material. Tensile tests were also conducted to validate the numerical model. The results indicate that the defect length can obviously influence the load and stress distributions along the rockbolt as well as the load-displacement response of the grouted system. Moreover, a plateau in the stress distribution forms due to the bond defect. The linear limit and peak load of the load-displacement response decrease as the defect length increases. A bond defect located closer to the loaded end leads to a longer nonlinear stage in the load-displacement response. However, the peak loads measured from the specimens made with various defect locations are almost approximately the same. The peak load for a specimen with the defects equally spaced along the bolt is higher than that for a specimen with defects concentrated in a certain zone, even with the same total defect length. Therefore, the dispersed pattern of bond defects would be much safer than the concentrated pattern. For the specimen with dispersed defects, the peak load increases with an increase in the defect spacing, even if the total defect length is the same. The peak load for a grouted rockbolt system with defects increases with an increases in the bolt diameter. This work leads to a better understanding of the load transfer mechanism for grouted rockbolt systems with bond defects, and paves the way towards developing a general evaluation method for damaged rockbolt grouted systems.

  2. Evaluation of solar gain through skylights for inclusion in the SP53 residential building loads data base

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

    Hanford, J.W.; Huang, Y.J.

    The energy performance of skylights is similar to that of windows in admitting solar heat gain, while at the same time providing a pathway for convective and conductive heat transfer through the building envelope. Since skylights are typically installed at angles ranging from 0{degrees} to 45{degrees}, and differ from windows in both their construction and operation, their conductive and convective heat gains or losses, as well as solar heat gain, will differ for the same rough opening and thermal characteristics. The objective of this work is to quantify the impact of solar gain through skylights on building heating and coolingmore » loads in 45 climates, and to develop a method for including these data into the SP53 residential loads data base previously developed by LBL in support of DOE`s Automated Residential Energy Standard (ARES) program. The authors used the DOE-2.1C program to simulate the heating and cooling loads of a prototypical residential building while varying the size and solar characteristics of skylights and windows. The results are presented as Skylight Solar Loads, which are the contribution of solar gains through skylights to the overall building heating and cooling loads, and as Skylight Solar Load Ratios, which are the ratios of skylight solar loads to those for windows with the same orientation. The study shows that skylight solar loads are larger than those for windows in both heating and cooling. Skylight solar cooling loads are from three to four times greater than those for windows regardless of the skylight tilt, except for those facing north. These cooling loads are largest for south-facing skylights at a tilt angle of approximately 20{degrees}, and drop off at higher tilts and other orientations.« less

  3. Force Limited Vibration Testing: Computation C2 for Real Load and Probabilistic Source

    NASA Astrophysics Data System (ADS)

    Wijker, J. J.; de Boer, A.; Ellenbroek, M. H. M.

    2014-06-01

    To prevent over-testing of the test-item during random vibration testing Scharton proposed and discussed the force limited random vibration testing (FLVT) in a number of publications, in which the factor C2 is besides the random vibration specification, the total mass and the turnover frequency of the load(test item), a very important parameter. A number of computational methods to estimate C2 are described in the literature, i.e. the simple and the complex two degrees of freedom system, STDFS and CTDFS, respectively. Both the STDFS and the CTDFS describe in a very reduced (simplified) manner the load and the source (adjacent structure to test item transferring the excitation forces, i.e. spacecraft supporting an instrument).The motivation of this work is to establish a method for the computation of a realistic value of C2 to perform a representative random vibration test based on force limitation, when the adjacent structure (source) description is more or less unknown. Marchand formulated a conservative estimation of C2 based on maximum modal effective mass and damping of the test item (load) , when no description of the supporting structure (source) is available [13].Marchand discussed the formal description of getting C 2 , using the maximum PSD of the acceleration and maximum PSD of the force, both at the interface between load and source, in combination with the apparent mass and total mass of the the load. This method is very convenient to compute the factor C 2 . However, finite element models are needed to compute the spectra of the PSD of both the acceleration and force at the interface between load and source.Stevens presented the coupled systems modal approach (CSMA), where simplified asparagus patch models (parallel-oscillator representation) of load and source are connected, consisting of modal effective masses and the spring stiffnesses associated with the natural frequencies. When the random acceleration vibration specification is given the CMSA method is suitable to compute the valueof the parameter C 2 .When no mathematical model of the source can be made available, estimations of the value C2 can be find in literature.In this paper a probabilistic mathematical representation of the unknown source is proposed, such that the asparagus patch model of the source can be approximated. The computation of the value C2 can be done in conjunction with the CMSA method, knowing the apparent mass of the load and the random acceleration specification at the interface between load and source, respectively.Strength & stiffness design rules for spacecraft, instrumentation, units, etc. will be practiced, as mentioned in ECSS Standards and Handbooks, Launch Vehicle User's manuals, papers, books , etc. A probabilistic description of the design parameters is foreseen.As an example a simple experiment has been worked out.

  4. Biomechanical analysis of a novel hemipelvic endoprosthesis during ascending and descending stairs.

    PubMed

    Liu, Dongxu; Hua, Zikai; Yan, Xinyi; Jin, Zhongmin

    2016-10-01

    In this study, the biomechanical characteristic of a newly developed adjustable hemipelvic prosthesis under dynamic loading conditions was investigated using explicit finite element method. Both intact and reconstructed pelvis models, including pelvis, femur and soft tissues, were established referring to human anatomic data using a solid geometry of a human pelvic bone. Hip contact forces during ascending stairs and descending stairs were imposed on pelvic models. Results showed that maximum von Mises stresses in reconstructed pelvis were 421.85 MPa for prostheses and 109.12 MPa for cortical bone, which were still within a low and elastic range below the yielding strength of Ti-6Al-4V and cortical bone, respectively. Besides, no significant difference of load transferring paths along pelvic rings was observed between the reconstructed pelvis and natural pelvis models. And good agreement was found between the overall distribution of maximum principal stresses in trabecular bones of reconstructed pelvis and natural pelvis, while at limited stances, principal stresses in trabecular bone of reconstructed pelvis were slightly lower than natural pelvis. The results indicated that the load transferring function of pelvis could be restored by this adjustable hemipelvic prosthesis. Moreover, the prosthesis was predicted to have a reliable short- and long-term performance. However, due to the occurrence of slightly lower principal stresses at a few stances, a porous structure applied on the interface between the prosthesis and bone would be studied in future work to obtain better long-term stability. © IMechE 2016.

  5. Motor phenotype and magnetic resonance measures of basal ganglia iron levels in Parkinson's disease☆

    PubMed Central

    Bunzeck, Nico; Singh-Curry, Victoria; Eckart, Cindy; Weiskopf, Nikolaus; Perry, Richard J.; Bain, Peter G.; Düzel, Emrah; Husain, Masud

    2013-01-01

    Background In Parkinson's disease the degree of motor impairment can be classified with respect to tremor dominant and akinetic rigid features. While tremor dominance and akinetic rigidity might represent two ends of a continuum rather than discrete entities, it would be important to have non-invasive markers of any biological differences between them in vivo, to assess disease trajectories and response to treatment, as well as providing insights into the underlying mechanisms contributing to heterogeneity within the Parkinson's disease population. Methods Here, we used magnetic resonance imaging to examine whether Parkinson's disease patients exhibit structural changes within the basal ganglia that might relate to motor phenotype. Specifically, we examined volumes of basal ganglia regions, as well as transverse relaxation rate (a putative marker of iron load) and magnetization transfer saturation (considered to index structural integrity) within these regions in 40 individuals. Results We found decreased volume and reduced magnetization transfer within the substantia nigra in Parkinson's disease patients compared to healthy controls. Importantly, there was a positive correlation between tremulous motor phenotype and transverse relaxation rate (reflecting iron load) within the putamen, caudate and thalamus. Conclusions Our findings suggest that akinetic rigid and tremor dominant symptoms of Parkinson's disease might be differentiated on the basis of the transverse relaxation rate within specific basal ganglia structures. Moreover, they suggest that iron load within the basal ganglia makes an important contribution to motor phenotype, a key prognostic indicator of disease progression in Parkinson's disease. PMID:24025315

  6. Modeling Force Transfer around Openings in Wood-Frame Shear Walls

    Treesearch

    Minghao Li; Frank Lam; Borjen Yeh; Tom Skaggs; Doug Rammer; James Wacker

    2012-01-01

    This paper presented a modeling study on force transfer around openings (FTAO) in wood-frame shear walls detailed for FTAO. To understand the load transfer in the walls, this study used a finite-element model WALL2D, which is able to model individual wall components, including framing members, sheathing panels, oriented panel-frame nailed connections, framing...

  7. 40 CFR 63.2343 - What are my requirements for emission sources not requiring control?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... of less than 18.9 cubic meters (5,000 gallons) and for each transfer rack subject to this subpart that only unloads organic liquids (i.e., no organic liquids are loaded at any of the transfer racks), you must keep documentation that verifies that each storage tank and transfer rack identified in...

  8. Efficient and flexible memory architecture to alleviate data and context bandwidth bottlenecks of coarse-grained reconfigurable arrays

    NASA Astrophysics Data System (ADS)

    Yang, Chen; Liu, LeiBo; Yin, ShouYi; Wei, ShaoJun

    2014-12-01

    The computational capability of a coarse-grained reconfigurable array (CGRA) can be significantly restrained due to data and context memory bandwidth bottlenecks. Traditionally, two methods have been used to resolve this problem. One method loads the context into the CGRA at run time. This method occupies very small on-chip memory but induces very large latency, which leads to low computational efficiency. The other method adopts a multi-context structure. This method loads the context into the on-chip context memory at the boot phase. Broadcasting the pointer of a set of contexts changes the hardware configuration on a cycle-by-cycle basis. The size of the context memory induces a large area overhead in multi-context structures, which results in major restrictions on application complexity. This paper proposes a Predictable Context Cache (PCC) architecture to address the above context issues by buffering the context inside a CGRA. In this architecture, context is dynamically transferred into the CGRA. Utilizing a PCC significantly reduces the on-chip context memory and the complexity of the applications running on the CGRA is no longer restricted by the size of the on-chip context memory. Data preloading is the most frequently used approach to hide input data latency and speed up the data transmission process for the data bandwidth issue. Rather than fundamentally reducing the amount of input data, the transferred data and computations are processed in parallel. However, the data preloading method cannot work efficiently because data transmission becomes the critical path as the reconfigurable array scale increases. This paper also presents a Hierarchical Data Memory (HDM) architecture as a solution to the efficiency problem. In this architecture, high internal bandwidth is provided to buffer both reused input data and intermediate data. The HDM architecture relieves the external memory from the data transfer burden so that the performance is significantly improved. As a result of using PCC and HDM, experiments running mainstream video decoding programs achieved performance improvements of 13.57%-19.48% when there was a reasonable memory size. Therefore, 1080p@35.7fps for H.264 high profile video decoding can be achieved on PCC and HDM architecture when utilizing a 200 MHz working frequency. Further, the size of the on-chip context memory no longer restricted complex applications, which were efficiently executed on the PCC and HDM architecture.

  9. Thermal conductivity investigation of adhesive-free bond laser components

    NASA Astrophysics Data System (ADS)

    Li, Da; Hong, Pengda; Vedula, MahaLakshmi; Meissner, Helmuth E.

    2017-02-01

    An interferometric method has been developed and employed at Onyx Optics, Inc. to accurately measure the thermal conductivity of laser-active crystals as function of dopant concentration or inactive materials such as single crystals, optical ceramics and glasses relative to a standard of assumed to be known thermal conductivity [1]. This technique can also provide information on heat transfer resistance at the interface between two materials in close thermal contact. While the technique appears generally applicable to composites between optically homogeneous materials, we report on thermal conductivities and heat transfer coefficients of selected adhesive-free bond (AFB®) laser composites. Single crystal bars and AFB bonded crystal doublets with the combinations of various rare-earth (Nd3+, Yb3+, Er3+, and Tm3+ trivalent ion doped YAG, and un-doped YAG have been fabricated with the AFB technique. By loading the test sample in a vacuum cryostat, with a precisely controlled heat load at one end of the doublets, the temperature distribution inside the single crystal or the composite samples can been precisely mapped by measuring the optical path difference interferometrically, given the material's thermal-optical properties. No measurable heat transfer resistance can be identified for the AFB interfaces between low-concentration doped YAG and un-doped YAG. For the heavily doped RE3+:YAG, for example, 10% Yb:YAG, the thermal conductivity measured in our experiment is 8.3 W/m•K, using the thermal conductivity of undoped YAG reported in [1] as basis. The thermal transfer resistance of the AFB interface with un-doped YAG, if there is any at the AFB interface, could be less than 1.29×10-6 m2•K/W.

  10. Thrive or overload? The effect of task complexity on novices' simulation-based learning.

    PubMed

    Haji, Faizal A; Cheung, Jeffrey J H; Woods, Nicole; Regehr, Glenn; de Ribaupierre, Sandrine; Dubrowski, Adam

    2016-09-01

    Fidelity is widely viewed as an important element of simulation instructional design based on its purported relationship with transfer of learning. However, higher levels of fidelity may increase task complexity to a point at which novices' cognitive resources become overloaded. In this experiment, we investigate the effects of variations in task complexity on novices' cognitive load and learning during simulation-based procedural skills training. Thirty-eight medical students were randomly assigned to simulation training on a simple or complex lumbar puncture (LP) task. Participants completed four practice trials on this task (skill acquisition). After 10 days of rest, all participants completed one additional trial on their assigned task (retention) and one trial on a 'very complex' simulation designed to be similar to the complex task (transfer). We assessed LP performance and cognitive load on each trial using multiple measures. In both groups, LP performance improved significantly during skill acquisition (p ≤ 0.047, f = 0.29-0.96) and was maintained at retention. The simple task group demonstrated superior performance compared with the complex task group throughout these phases (p ≤ 0.002, d = 1.13-2.31). Cognitive load declined significantly in the simple task group (p < 0.009, f = 0.48-0.76), but not in the complex task group during skill acquisition, and remained lower at retention (p ≤ 0.024, d = 0.78-1.39). Between retention and transfer, LP performance declined and cognitive load increased in the simple task group, whereas both remained stable in the complex task group. At transfer, no group differences were observed in LP performance and cognitive load, except that the simple task group made significantly fewer breaches of sterility (p = 0.023, d = 0.80). Reduced task complexity was associated with superior LP performance and lower cognitive load during skill acquisition and retention, but mixed results on transfer to a more complex task. These results indicate that task complexity is an important factor that may mediate (via cognitive overload) the relationship between instructional design elements (e.g. fidelity) and simulation-based learning outcomes. © 2016 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

  11. Biomechanical comparison between the trapezius transfer and latissimus transfer for irreparable posterosuperior rotator cuff tears.

    PubMed

    Omid, Reza; Heckmann, Nathanael; Wang, Lawrence; McGarry, Michelle H; Vangsness, C Thomas; Lee, Thay Q

    2015-10-01

    The purpose of this study was to characterize the biomechanical effects of the lower trapezius transfer and to compare it with the latissimus dorsi transfer in a cadaveric model of a massive posterosuperior rotator cuff tear. Eight cadaveric shoulders were tested at 0°, 30°, and 60° of shoulder abduction. Range of motion, humeral rotational position due to muscle loading, joint reaction forces, and kinematics were measured. All specimens were tested in 4 conditions: intact, massive posterosuperior cuff tear, lower trapezius transfer, and latissimus dorsi transfer. A repeated-measures analysis of variance was used for statistical analysis. Internal rotation due to muscle loading increased with massive cuff tear compared with the intact condition (P < .05). The latissimus transfer corrected this change at 0° abduction, whereas the trapezius transfer corrected this at all abduction angles. The massive cuff tear decreased glenohumeral joint compression forces at all abduction angles; these forces were restored by the lower trapezius transfer (P < .05). At maximum humeral internal rotation and 0° of abduction, the humeral head apex shifted superiorly and laterally with massive cuff tear (P < .05); this shift was more closely restored to intact values by the trapezius transfer compared with the latissimus transfer (P < .05). The lower trapezius transfer is superior to the latissimus transfer at restoring native glenohumeral kinematics and joint reaction forces in our cadaveric model. It may be a promising treatment option for patients with a massive irreparable rotator cuff tear. Published by Elsevier Inc.

  12. Coulomb stress transfer and tectonic loading preceding the 2002 Denali fault earthquake

    USGS Publications Warehouse

    Bufe, Charles G.

    2006-01-01

    Pre-2002 tectonic loading and Coulomb stress transfer are modeled along the rupture zone of the M 7.9 Denali fault earthquake (DFE) and on adjacent segments of the right-lateral Denali–Totschunda fault system in central Alaska, using a three-dimensional boundary-element program. The segments modeled closely follow, for about 95°, the arc of a circle of radius 375 km centered on an inferred asperity near the northeastern end of the intersection of the Patton Bay fault with the Alaskan megathrust under Prince William Sound. The loading model includes slip of 6 mm/yr below 12 km along the fault system, consistent with rotation of the Wrangell block about the asperity at a rate of about 1°/m.y. as well as slip of the Pacific plate at 5 cm/yr at depth along the Fairweather–Queen Charlotte transform fault system and on the Alaska megathrust. The model is consistent with most available pre-2002 Global Positioning System (GPS) displacement rate data. Coulomb stresses induced on the Denali–Totschunda fault system (locked above 12 km) by slip at depth and by transfer from the M 9.2 Prince William Sound earthquake of 1964 dominated the changing Coulomb stress distribution along the fault. The combination of loading (∼70–85%) and coseismic stress transfer from the great 1964 earthquake (∼15–30%) were the principal post-1900 stress factors building toward strike-slip failure of the northern Denali and Totschunda segments in the M 7.9 earthquake of November 2002. Postseismic stresses transferred from the 1964 earthquake may also have been a significant factor. The M 7.2–7.4 Delta River earthquake of 1912 (Carver et al., 2004) may have delayed or advanced the timing of the DFE, depending on the details and location of its rupture. The initial subevent of the 2002 DFE earthquake was on the 40-km Susitna Glacier thrust fault at the western end of the Denali fault rupture. The Coulomb stress transferred from the 1964 earthquake moved the Susitna Glacier thrust fault uniformly away from thrust failure by about 100 kPa. The initiation of the Denali fault earthquake was advanced by transfer of 30–50 kPa of positive Coulomb stress to the Susitna Glacier fault (Anderson and Ji, 2003) by the nearby M 6.7 Nenana Mountain foreshock of 23 October 2002. The regional tectonic loading model used here suggests that the Semidi (Alaska Peninsula) segment of the megathrust that ruptured in 1938 (M 8.2) may be reloaded and approaching failure.

  13. Nonlinear modeling of truss-plate joints

    Treesearch

    Leslie H. Groom; Anton Polensek

    1992-01-01

    A theoretical model is developed for predicting mechanisms of load transfer between a wood member and a metal die-punched truss plate. The model, which treats a truss-plate tooth as a beam on an inelastic foundation of wood and applies Runae-Kutta numerical analysis to solve the governing differentia1 equations, predicts the load-disp1acement trace and ultimate load of...

  14. Orbit transfer vehicle engine technology program. Task B-6 high speed turbopump bearings

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Bearing types were evaluated for use on the Orbit Transfer Vehicle (OTV) high pressure fuel pump. The high speed, high load, and long bearing life requirements dictated selection of hydrostatic bearings as the logical candidate for this engine. Design and fabrication of a bearing tester to evaluate these cryogenic hydrostatic bearings was then conducted. Detailed analysis, evaluation of bearing materials, and design of the hydrostatic bearings were completed resulting in fabrication of Carbon P5N and Kentanium hydrostatic bearings. Rotordynamic analyses determined the exact bearing geometry chosen. Instrumentation was evaluated and data acquisition methods were determined for monitoring shaft motion up to speeds in excess of 200,000 RPM in a cryogenic atmosphere. Fabrication of all hardware was completed, but assembly and testing was conducted outside of this contract.

  15. Preliminary In-Flight Loads Analysis of In-Line Launch Vehicles using the VLOADS 1.4 Program

    NASA Technical Reports Server (NTRS)

    Graham, J. B.; Luz, P. L.

    1998-01-01

    To calculate structural loads of in-line launch vehicles for preliminary design, a very useful computer program is VLOADS 1.4. This software may also be used to calculate structural loads for upper stages and planetary transfer vehicles. Launch vehicle inputs such as aerodynamic coefficients, mass properties, propellants, engine thrusts, and performance data are compiled and analyzed by VLOADS to produce distributed shear loads, bending moments, axial forces, and vehicle line loads as a function of X-station along the vehicle's length. Interface loads, if any, and translational accelerations are also computed. The major strength of the software is that it enables quick turnaround analysis of structural loads for launch vehicles during the preliminary design stage of its development. This represents a significant improvement over the alternative-the time-consuming, and expensive chore of developing finite element models. VLOADS was developed as a Visual BASIC macro in a Microsoft Excel 5.0 work book on a Macintosh. VLOADS has also been implemented on a PC computer using Microsoft Excel 7.0a for Windows 95. VLOADS was developed in 1996, and the current version was released to COSMIC, NASA's Software Technology Transfer Center, in 1997. The program is a copyrighted work with all copyright vested in NASA.

  16. High-throughput microcoil NMR of compound libraries using zero-dispersion segmented flow analysis.

    PubMed

    Kautz, Roger A; Goetzinger, Wolfgang K; Karger, Barry L

    2005-01-01

    An automated system for loading samples into a microcoil NMR probe has been developed using segmented flow analysis. This approach enhanced 2-fold the throughput of the published direct injection and flow injection methods, improved sample utilization 3-fold, and was applicable to high-field NMR facilities with long transfer lines between the sample handler and NMR magnet. Sample volumes of 2 microL (10-30 mM, approximately 10 microg) were drawn from a 96-well microtiter plate by a sample handler, then pumped to a 0.5-microL microcoil NMR probe as a queue of closely spaced "plugs" separated by an immiscible fluorocarbon fluid. Individual sample plugs were detected by their NMR signal and automatically positioned for stopped-flow data acquisition. The sample in the NMR coil could be changed within 35 s by advancing the queue. The fluorocarbon liquid wetted the wall of the Teflon transfer line, preventing the DMSO samples from contacting the capillary wall and thus reducing sample losses to below 5% after passage through the 3-m transfer line. With a wash plug of solvent between samples, sample-to-sample carryover was <1%. Significantly, the samples did not disperse into the carrier liquid during loading or during acquisitions of several days for trace analysis. For automated high-throughput analysis using a 16-second acquisition time, spectra were recorded at a rate of 1.5 min/sample and total deuterated solvent consumption was <0.5 mL (1 US dollar) per 96-well plate.

  17. Relative importance of expertise, lifting height and weight lifted on posture and lumbar external loading during a transfer task in manual material handling.

    PubMed

    Plamondon, André; Larivière, Christian; Delisle, Alain; Denis, Denys; Gagnon, Denis

    2012-01-01

    The objective of this study was to measure the effect size of three important factors in manual material handling, namely expertise, lifting height and weight lifted. The effect of expertise was evaluated by contrasting 15 expert and 15 novice handlers, the effect of the weight lifted with a 15-kg box and a 23-kg box and the effect of lifting height with two different box heights: ground level and a 32 cm height. The task consisted of transferring a series of boxes from a conveyor to a hand trolley. Lifting height and weight lifted had more effect size than expertise on external back loading variables (moments) while expertise had low impact. On the other hand, expertise showed a significant effect of posture variables on the lumbar spine and knees. All three factors are important, but for a reduction of external back loading, the focus should be on the lifting height and weight lifted. The objective was to measure the effect size of three important factors in a transfer of boxes from a conveyor to a hand trolley. Lifting height and weight lifted had more effect size than expertise on external back loading variables but expertise was a major determinant in back posture.

  18. A Multi-Cycle Q-Modulation for Dynamic Optimization of Inductive Links.

    PubMed

    Lee, Byunghun; Yeon, Pyungwoo; Ghovanloo, Maysam

    2016-08-01

    This paper presents a new method, called multi-cycle Q-modulation, which can be used in wireless power transmission (WPT) to modulate the quality factor (Q) of the receiver (Rx) coil and dynamically optimize the load impedance to maximize the power transfer efficiency (PTE) in two-coil links. A key advantage of the proposed method is that it can be easily implemented using off-the-shelf components without requiring fast switching at or above the carrier frequency, which is more suitable for integrated circuit design. Moreover, the proposed technique does not need any sophisticated synchronization between the power carrier and Q-modulation switching pulses. The multi-cycle Q-modulation is analyzed theoretically by a lumped circuit model, and verified in simulation and measurement using an off-the-shelf prototype. Automatic resonance tuning (ART) in the Rx, combined with multi-cycle Q-modulation helped maximizing PTE of the inductive link dynamically in the presence of environmental and loading variations, which can otherwise significantly degrade the PTE in multi-coil settings. In the prototype conventional 2-coil link, the proposed method increased the power amplifier (PA) plus inductive link efficiency from 4.8% to 16.5% at ( R L = 1 kΩ, d 23 = 3 cm), and from 23% to 28.2% at ( R L = 100 Ω, d 23 = 3 cm) after 11% change in the resonance capacitance, while delivering 168.1 mW to the load (PDL).

  19. Analysis of 2-spar cantilever wings with special reference to torsion and load transference

    NASA Technical Reports Server (NTRS)

    Kuhn, Paul

    1936-01-01

    This report deals with the analysis of 2-spar cantilever wings in torsion, taking cognizance of the fact that the spars are not independent, but are interconnected by ribs and other structural members. The principles of interaction are briefly explained, showing that the mutual relief action occurring depends on the "pure torsional stiffness" of the wing cross section. Various practical methods of analysis are outlined. The "Friedrichs-Von Karman equations" are shown to require the least amount of labor. Numerical examples by the several methods of analysis are given and the agreement between the calculation and experiment is shown.

  20. Putting the shoulder to the wheel: a new biomechanical model for the shoulder girdle.

    PubMed

    Levin, S M

    1997-01-01

    The least successfully modeled joint complex has been the shoulder. In multi-segmented mathematical shoulder models rigid beams (the bones) act as a series of columns or levers to transmit forces or loads to the axial skeleton. Forces passing through the almost frictionless joints must, somehow, always be directed perfectly perpendicular to the joints as only loads directed at right angles to the surfaces could transfer across frictionless joints. Loads transmitted to the axial skeleton would have to pass through the moving ribs or the weak jointed clavicle and then through the ribs. A new model of the shoulder girdle, based on the tension icosahedron described by Buckminster Fuller, is proposed that permits the compression loads passing through the arm and shoulder to be transferred to the axial skeleton through its soft tissues. In this model the scapula 'floats' in the tension network of shoulder girdle muscles just as the hub of the wire wheel is suspended in its tension network of spokes. With this construct inefficient beams and levers are eliminated. A more energy efficient, load distributing, integrated, hierarchical system is created.

  1. VIEW OF TRANSFER CAR (BATTERYELECTRIC POWERED) FROM BILLET YARD POSITIONED ...

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

    VIEW OF TRANSFER CAR (BATTERY-ELECTRIC POWERED) FROM BILLET YARD POSITIONED FOR LOADING BILLETS INTO FURNACE; HEATER (BEHIND SCREEN IN CENTER) MOVES THE TRANSFER CAR INTO POSITION. BILLETS FROM THE TRANSFER CAR ARE PLACED ON HAND-OPERATED TURNTABLE. THE FURNACE IS NATURAL-GAS FIRED, WITH BILLETS HEATED AT NOT MORE THAN 2400 DEGREES FAHRENHEIT. - Cambria Iron Company, Gautier Works, 12" Mill, Clinton Street & Little Conemaugh River, Johnstown, Cambria County, PA

  2. An environmental transfer hub for multimodal atom probe tomography

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

    Perea, Daniel E.; Gerstl, Stephan S. A.; Chin, Jackson

    Environmental control during transfer between instruments is required for specimens sensitive to air or thermal exposure to prevent morphological or chemical changes. Atom Probe Tomography is an expanding technique but commercial instruments remain limited to loading under ambient conditions. Here we describe a multifunctional environmental transfer hub allowing controlled cryogenic, atmospheric and vacuum transfer between an Atom Probe and other instruments containing separate chambers to allow downstream time-resolved in-situ studies.

  3. Prediction of storm transfers and annual loads with data-based mechanistic models using high-frequency data

    NASA Astrophysics Data System (ADS)

    Ockenden, Mary C.; Tych, Wlodek; Beven, Keith J.; Collins, Adrian L.; Evans, Robert; Falloon, Peter D.; Forber, Kirsty J.; Hiscock, Kevin M.; Hollaway, Michael J.; Kahana, Ron; Macleod, Christopher J. A.; Villamizar, Martha L.; Wearing, Catherine; Withers, Paul J. A.; Zhou, Jian G.; Benskin, Clare McW. H.; Burke, Sean; Cooper, Richard J.; Freer, Jim E.; Haygarth, Philip M.

    2017-12-01

    Excess nutrients in surface waters, such as phosphorus (P) from agriculture, result in poor water quality, with adverse effects on ecological health and costs for remediation. However, understanding and prediction of P transfers in catchments have been limited by inadequate data and over-parameterised models with high uncertainty. We show that, with high temporal resolution data, we are able to identify simple dynamic models that capture the P load dynamics in three contrasting agricultural catchments in the UK. For a flashy catchment, a linear, second-order (two pathways) model for discharge gave high simulation efficiencies for short-term storm sequences and was useful in highlighting uncertainties in out-of-bank flows. A model with non-linear rainfall input was appropriate for predicting seasonal or annual cumulative P loads where antecedent conditions affected the catchment response. For second-order models, the time constant for the fast pathway varied between 2 and 15 h for all three catchments and for both discharge and P, confirming that high temporal resolution data are necessary to capture the dynamic responses in small catchments (10-50 km2). The models led to a better understanding of the dominant nutrient transfer modes, which will be helpful in determining phosphorus transfers following changes in precipitation patterns in the future.

  4. Subject Load-Harness Interaction During Zero-Gravity Treadmill Exercise

    NASA Technical Reports Server (NTRS)

    McCrory, Jean L.; Baron, Heidi A.; Derr, Janice A.; Davis, Brian L.; Cavanagh, Peter R.

    1996-01-01

    When astronauts exercise on orbit, a subject load device (SLD) must be used to return the subject back to the supporting surface. The load in the SLD needs to be transferred the body by a harness which typically distributes this load between the pelvis and We shoulders. Through the use of a zero-gravity simulator, this research compared subject comfort and ground reaction forces during treadmill running at three levels of subject load (60%,80%, and 100% of body weight) in two harness designs ("shoulder only" and "waist "and shoulder ").

  5. Numerical simulations of heat transfer distribution of a two-pass square channel with V-rib turbulator and bleed holes

    NASA Astrophysics Data System (ADS)

    Kumar, Sourabh; Amano, R. S.; Lucci, Jose Martinez

    2013-08-01

    The blade tip region in gas turbine encounters high thermal loads due to temperature difference and hence efforts for high durability and safe operations are essential. Improved and robust methods of cooling are required to downgrade heat transfer rate to turbine blades. The blade tip regions, which are exposed to high gas flow, suffers high local thermal load which are due to external tip leakage. Jet impingement, pin cooling etc. are techniques used for cooling blades. A more usual way is to use serpentine passage with 180-degree turn. In this study, numerical simulation of heat transfer distribution of a two-pass square channel with rib turbulators and bleed holes were done. Periodical rib turbulators and bleed holes were used in the channel. The ribs arrangement were 60 degree V rib, 60 degree inverted V ribs, combination of 60 degree V rib at inlet and 60 inverted V rib at outlet section and combination of Inverted V at inlet and V rib at the outlet. The results were numerically computed using Fluent with Reynolds number of 12,500 and 28,500. Turbulence models used for computations were k-ω-SST and RSM. Temperature based and shear stress based techniques were used for heat transfer distribution prediction. The results for 60 degree V rib, 60 degree inverted V ribs were compared with the experimental results for validation of the results obtained. Detailed distribution shows distinctive peaks in heat transfer around bleed holes and rib turbulator. Comparisons of the overall performance of the models with different orientation of rib turbulator are presented. It is found that due to the combination of 60 degree inverted V rib in inlet and 60 V rib in outlet with bleed holes provides better heat treatment. It is suggested that the use of rib turbulator with bleed holes provides suitable for augmenting blade cooling to achieve an optimal balance between thermal and mechanical design requirements.

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

    Imani, Mohammadreza F., E-mail: mohamad.imani@gmail.com; Grbic, Anthony

    One of the obstacles preventing wireless power transfer from becoming ubiquitous is their leakage of power: high-amplitude electromagnetic fields that can interfere with other electronic devices, increase health concerns, or hinder power metering. In this paper, we present near-field plates (NFPs) as a novel method to tailor the electromagnetic fields generated by a wireless power transfer system while maintaining high efficiency. NFPs are modulated arrays or surfaces designed to form prescribed near-field patterns. The NFP proposed in this paper consists of an array of loaded loops that are designed to confine the electromagnetic fields of a resonant transmitting loop tomore » the desired direction (receiving loop) while suppressing fields in other directions. The step-by-step design procedure for this device is outlined. Two NFPs are designed and examined in full-wave simulation. Their performance is shown to be in close agreement with the design predictions, thereby verifying the proposed design and operation. A NFP is also fabricated and experimentally shown to form a unidirectional wireless power transfer link with high efficiency.« less

  7. Test-Anchored Vibration Response Predictions for an Acoustically Energized Curved Orthogrid Panel with Mounted Components

    NASA Technical Reports Server (NTRS)

    Frady, Gregory P.; Duvall, Lowery D.; Fulcher, Clay W. G.; Laverde, Bruce T.; Hunt, Ronald A.

    2011-01-01

    rich body of vibroacoustic test data was recently generated at Marshall Space Flight Center for component-loaded curved orthogrid panels typical of launch vehicle skin structures. The test data were used to anchor computational predictions of a variety of spatially distributed responses including acceleration, strain and component interface force. Transfer functions relating the responses to the input pressure field were generated from finite element based modal solutions and test-derived damping estimates. A diffuse acoustic field model was applied to correlate the measured input sound pressures across the energized panel. This application quantifies the ability to quickly and accurately predict a variety of responses to acoustically energized skin panels with mounted components. Favorable comparisons between the measured and predicted responses were established. The validated models were used to examine vibration response sensitivities to relevant modeling parameters such as pressure patch density, mesh density, weight of the mounted component and model form. Convergence metrics include spectral densities and cumulative root-mean squared (RMS) functions for acceleration, velocity, displacement, strain and interface force. Minimum frequencies for response convergence were established as well as recommendations for modeling techniques, particularly in the early stages of a component design when accurate structural vibration requirements are needed relatively quickly. The results were compared with long-established guidelines for modeling accuracy of component-loaded panels. A theoretical basis for the Response/Pressure Transfer Function (RPTF) approach provides insight into trends observed in the response predictions and confirmed in the test data. The software developed for the RPTF method allows easy replacement of the diffuse acoustic field with other pressure fields such as a turbulent boundary layer (TBL) model suitable for vehicle ascent. Structural responses using a TBL model were demonstrated, and wind tunnel tests have been proposed to anchor the predictions and provide new insight into modeling approaches for this environment. Finally, design load factors were developed from the measured and predicted responses and compared with those derived from traditional techniques such as historical Mass Acceleration Curves and Barrett scaling methods for acreage and component-loaded panels.

  8. An Elegant Sufficiency: Load-Aware Differentiated Scheduling of Data Transfers

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

    Kettimuthu, Rajkumar; Vardoyan, Gayane; Agrawal, Gagan

    2015-11-15

    We investigate the file transfer scheduling problem, where transfers among different endpoints must be scheduled to maximize pertinent metrics. We propose two new algorithms that exploit the fact that the aggregate bandwidth obtained over a network or at a storage system tends to increase with the number of concurrent transfers—but only up to a certain limit. The first algorithm, SEAL, uses runtime information and data-driven models to approximate system load and adapt transfer schedules and concurrency so as to maximize performance while avoiding saturation. We implement this algorithm using GridFTP as the transfer protocol and evaluate it using real transfermore » logs in a production WAN environment. Results show that SEAL can improve average slowdowns and turnaround times by up to 25% and worst-case slowdown and turnaround times by up to 50%, compared with the best-performing baseline scheme. Our second algorithm, STEAL, further leverages user-supplied categorization of transfers as either “interactive” (requiring immediate processing) or “batch” (less time-critical). Results show that STEAL reduces the average slowdown of interactive transfers by 63% compared to the best-performing baseline and by 21% compared to SEAL. For batch transfers, compared to the best-performing baseline, STEAL improves by 18% the utilization of the bandwidth unused by interactive transfers. By elegantly ensuring a sufficient, but not excessive, allocation of concurrency to the right transfers, we significantly improve overall performance despite constraints.« less

  9. F--Ray: A new algorithm for efficient transport of ionizing radiation

    NASA Astrophysics Data System (ADS)

    Mao, Yi; Zhang, J.; Wandelt, B. D.; Shapiro, P. R.; Iliev, I. T.

    2014-04-01

    We present a new algorithm for the 3D transport of ionizing radiation, called F2-Ray (Fast Fourier Ray-tracing method). The transfer of ionizing radiation with long mean free path in diffuse intergalactic gas poses a special challenge to standard numerical methods which transport the radiation in position space. Standard methods usually trace each individual ray until it is fully absorbed by the intervening gas. If the mean free path is long, the computational cost and memory load are likely to be prohibitive. We have developed an algorithm that overcomes these limitations and is, therefore, significantly more efficient. The method calculates the transfer of radiation collectively, using the Fast Fourier Transform to convert radiation between position and Fourier spaces, so the computational cost will not increase with the number of ionizing sources. The method also automatically combines parallel rays with the same frequency at the same grid cell, thereby minimizing the memory requirement. The method is explicitly photon-conserving, i.e. the depletion of ionizing photons is guaranteed to equal the photoionizations they caused, and explicitly obeys the periodic boundary condition, i.e. the escape of ionizing photons from one side of a simulation volume is guaranteed to be compensated by emitting the same amount of photons into the volume through the opposite side. Together, these features make it possible to numerically simulate the transfer of ionizing photons more efficiently than previous methods. Since ionizing radiation such as the X-ray is responsible for heating the intergalactic gas when first stars and quasars form at high redshifts, our method can be applied to simulate thermal distribution, in addition to cosmic reionization, in three-dimensional inhomogeneous cosmological density field.

  10. 40 CFR 63.2386 - What reports must I submit and when and what information is to be submitted in each?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... organic liquids were loaded at transfer racks that are subject to control based on the criteria specified... all transfer racks (except those racks at which only unloading of organic liquids occurs) and of tanks...) For each storage tank and transfer rack subject to control requirements, include periods of planned...

  11. A data acquisition and analysis system for the biomechanical evaluation of patient moving and transferring equipment and procedures.

    PubMed

    Allen, R; De Stefano, A

    2007-01-01

    Patients and people with various disabilities are frequently moved and transferred by nurses and carers and consequently it is important to assess the risks involved when undertaking such tasks. People with disabilities are often able to bear some of their weight and this has led to the development of non-mechanical aids designed to reduce the load on the nurse or carer when undertaking a transferring manoeuvre. It is essential that aids are assessed thoroughly in order to ensure that transfers are safe and that advice and guidance can be given on the most appropriate equipment in a given situation. This paper describes a data acquisition and analysis system that has been developed to assist in such assessments. The system integrates measurements of spine movements, foot pressure and knee flexion with video recording of a transferring manoeuvre. A biomechanical model provides an estimate of the loading at the bottom of the lumbar spine for comparison with National Institute for Occupational Safety and Health (NIOSH) guidelines. A pilot assessment of non-mechanical aids prior to a full user trial demonstrated that such a system can provide valuable data from which to assess risk during patient transferring manoeuvres.

  12. Site-specific gene delivery to stented arteries using magnetically guided zinc oleate-based nanoparticles loaded with adenoviral vectors

    PubMed Central

    Chorny, Michael; Fishbein, Ilia; Tengood, Jillian E.; Adamo, Richard F.; Alferiev, Ivan S.; Levy, Robert J.

    2013-01-01

    Gene therapeutic strategies have shown promise in treating vascular disease. However, their translation into clinical use requires pharmaceutical carriers enabling effective, site-specific delivery as well as providing sustained transgene expression in blood vessels. While replication-deficient adenovirus (Ad) offers several important advantages as a vector for vascular gene therapy, its clinical applicability is limited by rapid inactivation, suboptimal transduction efficiency in vascular cells, and serious systemic adverse effects. We hypothesized that novel zinc oleate-based magnetic nanoparticles (MNPs) loaded with Ad would enable effective arterial cell transduction by shifting vector processing to an alternative pathway, protect Ad from inactivation by neutralizing factors, and allow site-specific gene transfer to arteries treated with stent angioplasty using a 2-source magnetic guidance strategy. Ad-loaded MNPs effectively transduced cultured endothelial and smooth muscle cells under magnetic conditions compared to controls and retained capacity for gene transfer after exposure to neutralizing antibodies and lithium iodide, a lytic agent causing disruption of free Ad. Localized arterial gene expression significantly stronger than in control animal groups was demonstrated after magnetically guided MNP delivery in a rat stenting model 2 and 9 d post-treatment, confirming feasibility of using Ad-loaded MNPs to achieve site-specific transduction in stented blood vessels. In conclusion, Ad-loaded MNPs formed by controlled precipitation of zinc oleate represent a novel delivery system, well-suited for efficient, magnetically targeted vascular gene transfer.—Chorny, M., Fishbein, I., Tengood, J. E., Adamo, R. F., Alferiev, I. S., Levy, R. J. Site-specific gene delivery to stented arteries using magnetically guided zinc oleate-based nanoparticles loaded with adenoviral vectors. PMID:23407712

  13. Joining strength performances of metal skin and CFRP core laminate structures realized by compression-curing process, with supporting experiments

    NASA Astrophysics Data System (ADS)

    Quagliato, Luca; Jang, Changsoon; Kim, Naksoo

    2018-05-01

    In the recent years, the trend of lightening vehicles and structures of every kind has become an ever-growing issue, both for university and industrial researchers. As demonstrated in previous authors' works, laminate structures made of metal skin (MS) and carbon fiber reinforced polymer (CFRP) core show high specific bending strength properties while granting considerable weight reduction but, so far, no investigations have been carried out on the hole sensitivity and joinability of these hybrid structures. In the present research work, the hole size sensitivity of MS-CFRP structure has been studied by means of uniaxial tensile test on 160mm (length), 25mm (width), 2.0mm (average thickness) specimens bored with Ø06mm, Ø9mm, and Ø12mm holes. The specimen thickness is composed of two metal skins of 0.4mm thickness each, 8×0.2mm CFRP stacked layers and two thin epoxy-based adhesive layers. The specimens have been manufactured by means of a compression-curing process in which the different materials are stacked and, thanks to die pressure and temperature, the curing process is completed in a relatively short time (15˜20 minutes). The specimens have been tested by means of simple tension test showing that, for the MS-CFRP material, the smaller the hole the smaller the maximum bearable load. Moreover, specimens with the same hole sizes have been bolted together with class 12 resistance bolts and tested by means of tensile test, allowing to determine the maximum transferable load between the two MS-CFRP plates. Aiming to prove the improvement in the specific transferable load, experiments on only-steel specimens with the same weight of the MS-CFRP ones and joined with the same method and bolts have been carried out, allowing to conclude that, for the 9mm hole bolted plates, the proposed material has a specific maximum transferable 27% higher than that of the steel composing their skins.

  14. Silk fibroin nanoparticles prepared by electrospray as controlled release carriers of cisplatin.

    PubMed

    Qu, Jing; Liu, Yu; Yu, Yanni; Li, Jing; Luo, Jingwan; Li, Mingzhong

    2014-11-01

    To maintain the anti-tumor activity of cis-dichlorodiamminoplatinum (CDDP) while avoiding its cytotoxicity and negative influence on normal tissue, CDDP-loaded silk fibroin nanoparticles approximately 59 nm in diameter were successfully prepared by electrospray without using organic solvent. CDDP was incorporated into nanoparticles through metal-polymer coordination bond exchange. In vitro release tests showed that the cisplatin in the nanoparticles could be slowly and sustainably released for more than 15 days. In vitro anti-cancer experiments and intracellular Pt content testing indicated that CDDP-loaded silk fibroin nanoparticles were easily internalized by A549 lung cancer cells, transferring CDDP into cancer cells and then triggering their apoptosis. In contrast, the particles were not easily internalized by L929 mouse fibroblast cells and hence showed weaker cell growth inhibition. The CDDP-loaded silk fibroin nanoparticles showed sustained and efficient killing of tumor cells but weaker inhibition of normal cells. In general, this study provides not only a novel method for preparing CDDP-loaded silk fibroin nanoparticles but also a new carrier system for clinical therapeutic drugs against lung cancers and other tumors. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Intrauterine air impairs embryonic postimplantation development in mice.

    PubMed

    Liu, Ruonan; Li, Yimeng; Miao, Yanping; Wei, Yanhui; Guan, Mo; Zhou, Rongyan; Li, Xiangyun

    2017-12-01

    Although most embryologists load air bubbles into the catheter along with embryos during embryo transfer, the effects of these air bubbles on embryo transfer success rate are not clear. Air bubbles were nonsurgically injected into unilateral uterine horns of mice to demonstrate the negative effects of intrauterine air bubbles on embryonic development. Our data showed that when air bubbles are nonsurgically injected into unilateral uterine horns of pregnant 4days mice the litter size is significantly decreased. Four days after the introduction of air, abnormal decidua and dead conceptuses were detected in the uterine horns receiving the air bubbles. In addition, intrauterine air also significantly impaired murine embryo transfer success rates, and induced an increase in endometrial capillary permeability and decidualization in mice on day 4 of pseudopregnancy. These results strongly indicated that the air bubbles loaded into embryo transfer catheters to bracket the embryo-containing medium may have negative effect on embryonic implantation and development. Intrauterine air impaired murine embryonic postimplantation development, and this provided some clues for improving embryo transfer techniques in human. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Improving the accuracy of S02 column densities and emission rates obtained from upward-looking UV-spectroscopic measurements of volcanic plumes by taking realistic radiative transfer into account

    USGS Publications Warehouse

    Kern, Christoph; Deutschmann, Tim; Werner, Cynthia; Sutton, A. Jeff; Elias, Tamar; Kelly, Peter J.

    2012-01-01

    Sulfur dioxide (SO2) is monitored using ultraviolet (UV) absorption spectroscopy at numerous volcanoes around the world due to its importance as a measure of volcanic activity and a tracer for other gaseous species. Recent studies have shown that failure to take realistic radiative transfer into account during the spectral retrieval of the collected data often leads to large errors in the calculated emission rates. Here, the framework for a new evaluation method which couples a radiative transfer model to the spectral retrieval is described. In it, absorption spectra are simulated, and atmospheric parameters are iteratively updated in the model until a best match to the measurement data is achieved. The evaluation algorithm is applied to two example Differential Optical Absorption Spectroscopy (DOAS) measurements conducted at Kilauea volcano (Hawaii). The resulting emission rates were 20 and 90% higher than those obtained with a conventional DOAS retrieval performed between 305 and 315 nm, respectively, depending on the different SO2 and aerosol loads present in the volcanic plume. The internal consistency of the method was validated by measuring and modeling SO2 absorption features in a separate wavelength region around 375 nm and comparing the results. Although additional information about the measurement geometry and atmospheric conditions is needed in addition to the acquired spectral data, this method for the first time provides a means of taking realistic three-dimensional radiative transfer into account when analyzing UV-spectral absorption measurements of volcanic SO2 plumes.

  17. Mesh-free data transfer algorithms for partitioned multiphysics problems: Conservation, accuracy, and parallelism

    DOE PAGES

    Slattery, Stuart R.

    2015-12-02

    In this study we analyze and extend mesh-free algorithms for three-dimensional data transfer problems in partitioned multiphysics simulations. We first provide a direct comparison between a mesh-based weighted residual method using the common-refinement scheme and two mesh-free algorithms leveraging compactly supported radial basis functions: one using a spline interpolation and one using a moving least square reconstruction. Through the comparison we assess both the conservation and accuracy of the data transfer obtained from each of the methods. We do so for a varying set of geometries with and without curvature and sharp features and for functions with and without smoothnessmore » and with varying gradients. Our results show that the mesh-based and mesh-free algorithms are complementary with cases where each was demonstrated to perform better than the other. We then focus on the mesh-free methods by developing a set of algorithms to parallelize them based on sparse linear algebra techniques. This includes a discussion of fast parallel radius searching in point clouds and restructuring the interpolation algorithms to leverage data structures and linear algebra services designed for large distributed computing environments. The scalability of our new algorithms is demonstrated on a leadership class computing facility using a set of basic scaling studies. Finally, these scaling studies show that for problems with reasonable load balance, our new algorithms for both spline interpolation and moving least square reconstruction demonstrate both strong and weak scalability using more than 100,000 MPI processes with billions of degrees of freedom in the data transfer operation.« less

  18. Linear hydraulic drive system for a Stirling engine

    DOEpatents

    Walsh, Michael M.

    1984-02-21

    A hydraulic drive system operating from the periodic pressure wave produced by a Stirling engine along a first axis thereof and effecting transfer of power from the Stirling engine to a load apparatus therefor and wherein the movable, or working member of the load apparatus is reciprocatingly driven along an axis substantially at right angles to the first axis to achieve an arrangement of a Stirling engine and load apparatus assembly which is much shorter and the components of the load apparatus more readily accessible.

  19. 77 FR 71089 - Pilot Loading of Aeronautical Database Updates

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-29

    ... the use of newer systems and data-transfer mechanisms such as those employing wireless technology. In... which enables wireless updating of systems and databases. The current regulation does not accommodate... maintenance); Recordkeeping requirements; Training for pilots; Technological advancements in data-transfer...

  20. Brain-Behavior Mechanisms for the Transfer of Neuromuscular Training Adaptions to Simulated Sport: Initial Findings from the Train the Brain Project.

    PubMed

    Grooms, Dustin R; Kiefer, Adam W; Riley, Michael A; Ellis, Jonathan D; Thomas, Staci; Kitchen, Katie; DiCesare, Christopher; Bonnette, Scott; Gadd, Brooke; Barber Foss, Kim D; Yuan, Weihong; Silva, Paula; Galloway, Ryan; Diekfuss, Jed; Leach, James; Berz, Kate; Myer, Gregory D

    2018-03-27

    A limiting factor for reducing anterior cruciate ligament (ACL) injury risk is ensuring that the movement adaptions made during the prevention program transfer to sport-specific activity. Virtual reality provides a mechanism to assess transferability and neuroimaging provides a means to assay the neural processes allowing for such skill transfer. To determine the neural mechanisms for injury risk reducing biomechanics transfer to sport after ACL injury prevention training. Cohort study Setting: Research laboratory Participants: Four healthy high school soccer athletes. Participants completed augmented neuromuscular training utilizing real-time visual feedback. An unloaded knee extension task and a loaded leg-press task was completed with neuroimaging before and after training. A virtual reality soccer specific landing task was also competed following training to assess transfer of movement mechanics. Landing mechanics during the virtual reality soccer task and blood oxygen level dependent signal change during neuroimaging. Increased motor planning, sensory and visual region activity during unloaded knee extension and decreased motor cortex activity during loaded leg-press were highly correlated with improvements in landing mechanics (decreased hip adduction and knee rotation). Changes in brain activity may underlie adaptation and transfer of injury risk reducing movement mechanics to sport activity. Clinicians may be able to target these specific brain processes with adjunctive therapy to facilitate intervention improvements transferring to sport.

  1. On the calculation of dynamic and heat loads on a three-dimensional body in a hypersonic flow

    NASA Astrophysics Data System (ADS)

    Bocharov, A. N.; Bityurin, V. A.; Evstigneev, N. M.; Fortov, V. E.; Golovin, N. N.; Petrovskiy, V. P.; Ryabkov, O. I.; Teplyakov, I. O.; Shustov, A. A.; Solomonov, Yu S.

    2018-01-01

    We consider a three-dimensional body in a hypersonic flow at zero angle of attack. Our aim is to estimate heat and aerodynamic loads on specific body elements. We are considering a previously developed code to solve coupled heat- and mass-transfer problem. The change of the surface shape is taken into account by formation of the iterative process for the wall material ablation. The solution is conducted on the multi-graphics-processing-unit (multi-GPU) cluster. Five Mach number points are considered, namely for M = 20-28. For each point we estimate body shape after surface ablation, heat loads on the surface and aerodynamic loads on the whole body and its elements. The latter is done using Gauss-type quadrature on the surface of the body. The comparison of the results for different Mach numbers is performed. We also estimate the efficiency of the Navier-Stokes code on multi-GPU and central processing unit architecture for the coupled heat and mass transfer problem.

  2. The Impact of the Invasive Alien Plant, Impatiens glandulifera, on Pollen Transfer Networks

    PubMed Central

    Emer, Carine; Vaughan, Ian P.; Hiscock, Simon; Memmott, Jane

    2015-01-01

    Biological invasions are a threat to the maintenance of ecological processes, including pollination. Plant-flower visitor networks are traditionally used as a surrogated for pollination at the community level, despite they do not represent the pollination process, which takes place at the stigma of plants where pollen grains are deposited. Here we investigated whether the invasion of the alien plant Impatiens glandulifera (Balsaminaceae) affects pollen transfer at the community level. We asked whether more alien pollen is deposited on the stigmas of plants on invaded sites, whether deposition is affected by stigma type (dry, semidry and wet) and whether the invasion of I. glandulifera changes the structure of the resulting pollen transfer networks. We sampled stigmas of plants on 10 sites invaded by I. glandulifera (hereafter, balsam) and 10 non-invaded control sites. All 20 networks had interactions with balsam pollen, although significantly more balsam pollen was found on plants with dry stigmas in invaded areas. Balsam pollen deposition was restricted to a small subset of plant species, which is surprising because pollinators are known to carry high loads of balsam pollen. Balsam invasion did not affect the loading of native pollen, nor did it affect pollen transfer network properties; networks were modular and poorly nested, both of which are likely to be related to the specificity of pollen transfer interactions. Our results indicate that pollination networks become more specialized when moving from the flower visitation to the level of pollen transfer networks. Therefore, caution is needed when inferring pollination from patterns of insect visitation or insect pollen loads as the relationship between these and pollen deposition is not straightforward. PMID:26633170

  3. Design of crashworthy structures with controlled behavior in HCA framework

    NASA Astrophysics Data System (ADS)

    Bandi, Punit

    The field of crashworthiness design is gaining more interest and attention from automakers around the world due to increasing competition and tighter safety norms. In the last two decades, topology and topometry optimization methods from structural optimization have been widely explored to improve existing designs or conceive new designs with better crashworthiness. Although many gradient-based and heuristic methods for topology- and topometry-based crashworthiness design are available these days, most of them result in stiff structures that are suitable only for a set of vehicle components in which maximizing the energy absorption or minimizing the intrusion is the main concern. However, there are some other components in a vehicle structure that should have characteristics of both stiffness and flexibility. Moreover, the load paths within the structure and potential buckle modes also play an important role in efficient functioning of such components. For example, the front bumper, side frame rails, steering column, and occupant protection devices like the knee bolster should all exhibit controlled deformation and collapse behavior. The primary objective of this research is to develop new methodologies to design crashworthy structures with controlled behavior. The well established Hybrid Cellular Automaton (HCA) method is used as the basic framework for the new methodologies, and compliant mechanism-type (sub)structures are the highlight of this research. The ability of compliant mechanisms to efficiently transfer force and/or motion from points of application of input loads to desired points within the structure is used to design solid and tubular components that exhibit controlled deformation and collapse behavior under crash loads. In addition, a new methodology for controlling the behavior of a structure under multiple crash load scenarios by adaptively changing the contributions from individual load cases is developed. Applied to practical design problems, the results demonstrate that the methodologies provide a practical tool to aid the design engineer in generating design concepts for crashworthy structures with controlled behavior. Although developed in the HCA framework, the basic ideas behind these methods are generic and can be easily implemented with other available topology- and topometry-based optimization methods.

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

    Zhang, Junsong; Hao, Shijie; Yu, Cun

    The deformation behavior and load transfer of a dual-phase composite composed of martensite NiTi embedded in brittle Ti{sub 2}Ni matrices were investigated by using in situ synchrotron x-ray diffraction during compression. The composite exhibits a stage-wise deformation feature and a double-yielding phenomenon, which were caused by the interaction between Ti{sub 2}Ni and NiTi with alternative microscopic deformation mechanism. No load transfer occurs from the soft NiTi dendrites to the hard Ti{sub 2}Ni matrices during the pseudoplastic deformation (detwinning) of NiTi, which is significantly different from that previously reported in bulk metallic glasses matrices composites.

  5. Characterizing the constitutive response and energy absorption of rigid polymeric foams subjected to intermediate-velocity impact

    DOE PAGES

    Koohbor, Behrad; Kidane, Addis; Lu, Wei-Yang

    2016-06-27

    As an optimum energy-absorbing material system, polymeric foams are needed to dissipate the kinetic energy of an impact, while maintaining the impact force transferred to the protected object at a low level. As a result, it is crucial to accurately characterize the load bearing and energy dissipation performance of foams at high strain rate loading conditions. There are certain challenges faced in the accurate measurement of the deformation response of foams due to their low mechanical impedance. In the present work, a non-parametric method is successfully implemented to enable the accurate assessment of the compressive constitutive response of rigid polymericmore » foams subjected to impact loading conditions. The method is based on stereovision high speed photography in conjunction with 3D digital image correlation, and allows for accurate evaluation of inertia stresses developed within the specimen during deformation time. In conclusion, full-field distributions of stress, strain and strain rate are used to extract the local constitutive response of the material at any given location along the specimen axis. In addition, the effective energy absorbed by the material is calculated. Finally, results obtained from the proposed non-parametric analysis are compared with data obtained from conventional test procedures.« less

  6. Micro-motors: A motile bacteria based system for liposome cargo transport.

    PubMed

    Dogra, Navneet; Izadi, Hadi; Vanderlick, T Kyle

    2016-07-05

    Biological micro-motors (microorganisms) have potential applications in energy utilization and nanotechnology. However, harnessing the power generated by such motors to execute desired work is extremely difficult. Here, we employ the power of motile bacteria to transport small, large, and giant unilamellar vesicles (SUVs, LUVs, and GUVs). Furthermore, we demonstrate bacteria-bilayer interactions by probing glycolipids inside the model membrane scaffold. Fluorescence Resonance Energy Transfer (FRET) spectroscopic and microscopic methods were utilized for understanding these interactions. We found that motile bacteria could successfully propel SUVs and LUVs with a velocity of 28 μm s(-1) and 13 μm s(-1), respectively. GUVs, however, displayed Brownian motion and could not be propelled by attached bacteria. Bacterial velocity decreased with the larger loaded cargo, which agrees with our calculations of loaded bacteria swimming at low Reynolds number.

  7. Continuum Absorption Coefficient of Atoms and Ions

    NASA Technical Reports Server (NTRS)

    Armaly, B. F.

    1979-01-01

    The rate of heat transfer to the heat shield of a Jupiter probe has been estimated to be one order of magnitude higher than any previously experienced in an outer space exploration program. More than one-third of this heat load is due to an emission of continuum radiation from atoms and ions. The existing computer code for calculating the continuum contribution to the total load utilizes a modified version of Biberman's approximate method. The continuum radiation absorption cross sections of a C - H - O - N ablation system were examined in detail. The present computer code was evaluated and updated by being compared with available exact and approximate calculations and correlations of experimental data. A detailed calculation procedure, which can be applied to other atomic species, is presented. The approximate correlations can be made to agree with the available exact and experimental data.

  8. Application of Novel Lateral Tire Force Sensors to Vehicle Parameter Estimation of Electric Vehicles.

    PubMed

    Nam, Kanghyun

    2015-11-11

    This article presents methods for estimating lateral vehicle velocity and tire cornering stiffness, which are key parameters in vehicle dynamics control, using lateral tire force measurements. Lateral tire forces acting on each tire are directly measured by load-sensing hub bearings that were invented and further developed by NSK Ltd. For estimating the lateral vehicle velocity, tire force models considering lateral load transfer effects are used, and a recursive least square algorithm is adapted to identify the lateral vehicle velocity as an unknown parameter. Using the estimated lateral vehicle velocity, tire cornering stiffness, which is an important tire parameter dominating the vehicle's cornering responses, is estimated. For the practical implementation, the cornering stiffness estimation algorithm based on a simple bicycle model is developed and discussed. Finally, proposed estimation algorithms were evaluated using experimental test data.

  9. Acoustic field modulation in regenerators

    NASA Astrophysics Data System (ADS)

    Hu, J. Y.; Wang, W.; Luo, E. C.; Chen, Y. Y.

    2016-12-01

    The regenerator is a key component that transfers energy between heat and work. The conversion efficiency is significantly influenced by the acoustic field in the regenerator. Much effort has been spent to quantitatively determine this influence, but few comprehensive experimental verifications have been performed because of difficulties in modulating and measuring the acoustic field. In this paper, a method requiring two compressors is introduced and theoretically investigated that achieves acoustic field modulation in the regenerator. One compressor outputs the acoustic power for the regenerator; the other acts as a phase shifter. A RC load dissipates the acoustic power out of both the regenerator and the latter compressor. The acoustic field can be modulated by adjusting the current in the two compressors and opening the RC load. The acoustic field is measured with pressure sensors instead of flow-field imaging equipment, thereby greatly simplifying the experiment.

  10. Experimental studies of the effects of buffered particle dampers attached to a multi-degree-of-freedom system under dynamic loads

    NASA Astrophysics Data System (ADS)

    Lu, Zheng; Lu, Xilin; Lu, Wensheng; Masri, Sami F.

    2012-04-01

    This paper presents a systematic experimental investigation of the effects of buffered particle dampers attached to a multi-degree-of-freedom (mdof) system under different dynamic loads (free vibration, random excitation as well as real onsite earthquake excitations), and analytical/computational study of such a system. A series of shaking table tests of a three-storey steel frame with the buffered particle damper system are carried out to evaluate the performance and to verify the analysis method. It is shown that buffered particle dampers have good performance in reducing the response of structures under dynamic loads, especially under random excitation case. It can effectively control the fundamental mode of the mdof primary system; however, the control effect for higher modes is variable. It is also shown that, for a specific container geometry, a certain mass ratio leads to more efficient momentum transfer from the primary system to the particles with a better vibration attenuation effect, and that buffered particle dampers have better control effect than the conventional rigid ones. An analytical solution based on the discrete element method is also presented. Comparison between the experimental and computational results shows that reasonably accurate estimates of the response of a primary system can be obtained. Properly designed buffered particle dampers can effectively reduce the response of lightly damped mdof primary system with a small weight penalty, under different dynamic loads.

  11. Disentangling nutrient concentrations trends in transfer pathways of agricultural watersheds

    NASA Astrophysics Data System (ADS)

    Mellander, P. E.; Jordan, P.

    2017-12-01

    Targeted schemes designed to attenuate agricultural pollution to water are needed to reach goals of sustainable food production. Such approaches require insight into temporal and spatial variability in the most representative flows and active pollution transfer pathways. Interpreting changes in total stream flow can be misleading since some changes may only be apparent in specific pathways. The aim of this study was to investigate changing land use pressures on water quality. The objectives were to assess intra-annual and inter-annual changes in phosphorus (P) and nitrogen (N) concentrations and loads in apportioned pathways. Pathways were separated using hydrograph and loadograph separation techniques on a seven-year dataset of sub-hourly river discharge and concentrations of NO3-N, reactive P and total P in two intensively managed agricultural watersheds of contrasting hydrology in Ireland. Active transfer pathways were dictated by soil drainage. There were intra-annual variability in both P and N concentrations in different pathways and loads, and these had the largest influence of all-year baseflow (BF) concentrations and summer quickflow (QF) concentrations. Nutrient loss responded to seasonality in the river discharge in all pathways in both watersheds and was mostly transport limited. In both watersheds there were inter-annual trends in P concentration in some pathways and seasons that did not correspond to the trend of total river P concentration. The response in stream water quality to management, mitigation measures and changes in weather may be hidden by counteracting responses in different pathways. The hydrology had a major impact on seasonal changes in N and P loss. By apportioning different transfer pathways more information on the temporal and site-specific nature of nutrient transfer was provided. BF and QF pathways largely contributed to the river P concentrations in summer while all pathways contributed to the P and N loads in wintertime. The data indicated that increasing trends in river P concentrations were mostly linked to trends in BF concentration in both catchment types. This may be explained by increased point source influence, increased vertical transfer through increased soil P loading, or decreased stream bed attenuation. Each will require different policy considerations.

  12. Numerical Analysis of Coolant Flow and Heat Transfer in ITER Diagnostic First Wall

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

    Khodak, A.; Loesser, G.; Zhai, Y.

    2015-07-24

    We performed numerical simulations of the ITER Diagnostic First Wall (DFW) using ANSYS workbench. During operation DFW will include solid main body as well as liquid coolant. Thus thermal and hydraulic analysis of the DFW was performed using conjugated heat transfer approach, in which heat transfer was resolved in both solid and liquid parts, and simultaneously fluid dynamics analysis was performed only in the liquid part. This approach includes interface between solid and liquid part of the systemAnalysis was performed using ANSYS CFX software. CFX software allows solution of heat transfer equations in solid and liquid part, and solution ofmore » the flow equations in the liquid part. Coolant flow in the DFW was assumed turbulent and was resolved using Reynolds averaged Navier-Stokes equations with Shear Stress Transport turbulence model. Meshing was performed using CFX method available within ANSYS. The data cloud for thermal loading consisting of volumetric heating and surface heating was imported into CFX Volumetric heating source was generated using Attila software. Surface heating was obtained using radiation heat transfer analysis. Our results allowed us to identify areas of excessive heating. Proposals for cooling channel relocation were made. Additional suggestions were made to improve hydraulic performance of the cooling system.« less

  13. Methods for heat transfer and temperature field analysis of the insulated diesel, phase 3

    NASA Technical Reports Server (NTRS)

    Morel, Thomas; Wahiduzzaman, Syed; Fort, Edward F.; Keribar, Rifat; Blumberg, Paul N.

    1988-01-01

    Work during Phase 3 of a program aimed at developing a comprehensive heat transfer and thermal analysis methodology for design analysis of insulated diesel engines is described. The overall program addresses all the key heat transfer issues: (1) spatially and time-resolved convective and radiative in-cylinder heat transfer, (2) steady-state conduction in the overall structure, and (3) cyclical and load/speed temperature transients in the engine structure. These are all accounted for in a coupled way together with cycle thermodynamics. This methodology was developed during Phases 1 and 2. During Phase 3, an experimental program was carried out to obtain data on heat transfer under cooled and insulated engine conditions and also to generate a database to validate the developed methodology. A single cylinder Cummins diesel engine was instrumented for instantaneous total heat flux and heat radiation measurements. Data were acquired over a wide range of operating conditions in two engine configurations. One was a cooled baseline. The other included ceramic coated components (0.050 inches plasma sprayed zirconia)-piston, head and valves. The experiments showed that the insulated engine has a smaller heat flux than the cooled one. The model predictions were found to be in very good agreement with the data.

  14. Measuring CO 2 and N 2 O Mass Transfer into GAP-1 CO 2 –Capture Solvents at Varied Water Loadings

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

    Whyatt, Greg A.; Zwoster, Andy; Zheng, Feng

    This paper investigates the CO 2 and N 2 O absorption behavior in the water-lean gamma amino propyl (GAP)-1/TEG solvent system using a wetted-wall contactor. Testing was performed on a blend of GAP-1 aminosilicone in triethylene glycol at varied water loadings in the solvent. Measurements were made with CO 2 and N 2 O at representative lean (0.04 mol CO 2/mol alkalinity), middle (0.13 mol CO 2 /mol alkalinity) and rich (0.46 mol CO 2 /mol alkalinity) solvent loadings at 0, 5, 10 and 15 wt% water loadings at 40, 60 and 80C° and N 2 O at (0.08-0.09 molmore » CO 2 /mol alkalinity) at 5 wt% water at 40, 60 and 80C°. CO 2 flux was found to be non-linear with respect to log mean pressure driving force (LMPD). Liquid-film mass transfer coefficients (k'g) were calculated by subtracting the gas film resistance (determined from a correlation from literature) from the overall mass transfer measurement. The resulting k'g values for CO 2 and N 2 O in GAP-1/TEG mixtures were found to be higher than that of 5M aqueous monoethanolamine under comparable driving force albeit at higher solvent viscosities. The k'g values for CO 2 were also found to decrease with increasing solvent water content and increase with a decrease in temperature. These observations indicate that mass transfer of CO 2 in GAP-1/TEG is linked to the physical solubility of CO 2 , which is higher in organic solvents compared to water. This paper expands on the understanding of the unique mass transfer behavior and kinetics of CO 2 capture in water-lean solvents.« less

  15. Variation in flow and suspended sediment transport in a montane river affected by hydropeaking and instream mining

    NASA Astrophysics Data System (ADS)

    Béjar, M.; Vericat, D.; Batalla, R. J.; Gibbins, C. N.

    2018-06-01

    The temporal and spatial variability of water and sediment loads of rivers is controlled by a suite of factors whose individual effects are often difficult to disentangle. While land use changes and localised human activities such as instream mining and hydropeaking alter water and sediment transfer, tributaries naturally contribute to discharge and sediment load of mainstem rivers, and so may help compensate upstream anthropogenic factors. The work presented here aimed to assess water and the sediment transfer in a river reach affected by gravel extraction and hydropeaking, set against a backdrop of changes to the supply of water and sediment from tributaries. Discharge and suspended sediment transport were monitored during two average hydrological years at three cross-sections along a 10-km reach of the upper River Cinca, in the Southern Pyrenees. Water and sediment loads differed substantially between the reaches. The upper reach showed a largely torrential discharge regime, controlled mainly by floods, and had high but variable water and sediment loads. The middle reach was influenced markedly by hydropeaking and tributary inflows, which increased its annual water yield four-fold. Suspended sediment load in this reach increased by only 25% compared to upstream, indicating that dilution predominated. In the lowermost section, while discharge remained largely unaltered, sediment load increased appreciably as a result of changes to sediment availability from instream mining and inputs from tributaries. At the reach scale, snowmelt and summer and autumn thunderstorms were responsible for most of the water yield, while flood flows determined the magnitude and transport of the sediment load. The study highlights that a combination of natural and human factors control the spatial and temporal transfer of water and sediment in river channels and that, depending on their geographic location and effect-size, can result in marked variability even over short downstream distances.

  16. Vehicle Exhaust Waste Heat Recovery Model with Integrated Thermal Load Leveling

    DTIC Science & Technology

    2015-08-01

    recovery from automobile engine. Energy. 2010;35:1447–1454. 14 12. Ceraianu MO, Gontean A. Parasitic elements modelling in thermoelectric...JP, Sampath S. Heat transfer modeling and geometry optimization of TEG for automobile applications. Proceedings of the ASME Summer Heat Transfer

  17. Pilot project - demonstration of capabilities and benefits of bridge load rating through physical testing : tech transfer summary.

    DOT National Transportation Integrated Search

    2013-08-01

    This project demonstrated the capabilities for load testing bridges in Iowa, developed and presented a webinar to local and state engineers, and produced a spreadsheet and benefit evaluation matrix that others can use to preliminarily assess where br...

  18. Power generation in microbial fuel cells using platinum group metal-free cathode catalyst: Effect of the catalyst loading on performance and costs

    NASA Astrophysics Data System (ADS)

    Santoro, Carlo; Kodali, Mounika; Herrera, Sergio; Serov, Alexey; Ieropoulos, Ioannis; Atanassov, Plamen

    2018-02-01

    Platinum group metal-free (PGM-free) catalyst with different loadings was investigated in air breathing electrodes microbial fuel cells (MFCs). Firstly, the electrocatalytic activity towards oxygen reduction reaction (ORR) of the catalyst was investigated by rotating ring disk electrode (RRDE) setup with different catalyst loadings. The results showed that higher loading led to an increased in the half wave potential and the limiting current and to a further decrease in the peroxide production. The electrons transferred also slightly increased with the catalyst loading up to the value of ≈3.75. This variation probably indicates that the catalyst investigated follow a 2x2e- transfer mechanism. The catalyst was integrated within activated carbon pellet-like air-breathing cathode in eight different loadings varying between 0.1 mgcm-2 and 10 mgcm-2. Performance were enhanced gradually with the increase in catalyst content. Power densities varied between 90 ± 9 μWcm-2 and 262 ± 4 μWcm-2 with catalyst loading of 0.1 mgcm-2 and 10 mgcm-2 respectively. Cost assessments related to the catalyst performance are presented. An increase in catalyst utilization led to an increase in power generated with a substantial increase in the whole costs. Also a decrease in performance due to cathode/catalyst deterioration over time led to a further increase in the costs.

  19. Effects of Interlocking and Supporting Conditions on Concrete Block Pavements

    NASA Astrophysics Data System (ADS)

    Mahapatra, Geetimukta; Kalita, Kuldeep

    2018-02-01

    Concrete Block Paving (CBP) is widely used as wearing course in flexible pavements, preferably under light and medium vehicular loadings. Construction of CBP at site is quick and easy in quality control. Usually, flexible pavement design philosophy is followed in CBP construction, though it is structurally different in terms of small block elements with high strength concrete and their interlocking aspects, frequent joints and discontinuity, restrained edge etc. Analytical solution for such group action of concrete blocks under loading in a three dimensional multilayer structure is complex and thus, the need of conducting experimental studies is necessitated for extensive understanding of the load—deformation characteristics and behavior of concrete blocks in pavement. The present paper focuses on the experimental studies for load transfer characteristics of CBP under different interlocking and supporting conditions. It is observed that both interlocking and supporting conditions affect significantly on the load transfer behavior in CBP structures. Coro-lock block exhibits better performance in terms of load carrying capacity and distortion behavior under static loads. Plate load tests are performed over subgrade, granular sub-base (GSB), CBP with and without GSB using different block shapes. For an example case, the comparison of CBP with conventional flexible pavement section is also presented and it is found that CBP provides considerable benefit in terms of construction cost of the road structure.

  20. Fabrication of Polymeric Micelles with Aggregation-Induced Emission and Forster Resonance Energy Transfer for Anticancer Drug Delivery.

    PubMed

    Hao, Na; Sun, Changzhen; Wu, Zhengfei; Xu, Long; Gao, Wenxia; Cao, Jun; Li, Li; He, Bin

    2017-07-19

    With the aim of obtaining effective cancer therapy with simultaneous cellular imaging, dynamic drug-release monitoring, and chemotherapeutic treatment, a polymeric micelle with aggregation-induced emission (AIE) imaging and a Forster resonance energy transfer (FRET) effect was fabricated as the drug carrier. An amphiphilic conjugate of 1H-pyrrole-1-propanoicacid (MAL)-poly(ethylene glycol) (PEG)-Tripp-bearing AIE molecules were synthesized and self-assembled into micelles to load the anticancer drug doxorubicin (DOX). Spherical DOX-loaded micelles with the mean size of 106 nm were obtained with good physiological stability (CMC, 12.5 μg/mL), high drug-loading capacity (10.4%), and encapsulation efficiency (86%). The cellular uptake behavior of DOX-loaded MAL-PEG-Tripp micelles was visible for high-quality intracellular imaging due to the AIE property. The delivery of DOX from the drug-loaded micelles was dynamic monitored by the FRET effect between the DOX and MAL-PEG-Tripp. Both in vitro (IC50, 2.36 μg/mL) and in vivo anticancer activity tests revealed that the DOX-loaded MAL-PEG-Tripp micelles exhibited promising therapeutic efficacy to cancer with low systematic toxicity. In summary, this micelle provided an effective way to fabricate novel nanoplatform for intracellular imaging, drug-delivery tracing, and chemotherapy.

  1. The structure of a ring-opened proliferating cell nuclear antigen-replication factor C complex revealed by fluorescence energy transfer.

    PubMed

    Zhuang, Zhihao; Yoder, Bonita L; Burgers, Peter M J; Benkovic, Stephen J

    2006-02-21

    Numerous proteins that function in DNA metabolic pathways are known to interact with the proliferating cell nuclear antigen (PCNA). The important function of PCNA in stimulating various cellular activities requires its topological linkage with DNA. Loading of the circular PCNA onto duplex DNA requires the activity of a clamp-loader [replication factor C (RFC)] complex and the energy derived from ATP hydrolysis. The mechanistic and structural details regarding PCNA loading by the RFC complex are still developing. In particular, the positive identification of a long-hypothesized structure of an open clamp-RFC complex as an intermediate in loading has remained elusive. In this study, we capture an open yeast PCNA clamp in a complex with RFC through fluorescence energy transfer experiments. We also follow the topological transitions of PCNA in the various steps of the clamp-loading pathway through both steady-state and stopped-flow fluorescence studies. We find that ATP effectively drives the clamp-loading process to completion with the formation of the closed PCNA bound to DNA, whereas ATPgammaS cannot. The information derived from this work complements that obtained from previous structural and mechanistic studies and provides a more complete picture of a eukaryotic clamp-loading pathway using yeast as a paradigm.

  2. Load partitioning in Ai{sub 2}0{sub 3-}Al composites with three- dimensional periodic architecture.

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

    Young, M. L.; Rao, R.; Almer, J. D.

    2009-05-01

    Interpenetrating composites are created by infiltration of liquid aluminum into three-dimensional (3-D) periodic Al{sub 2}O{sub 3} preforms with simple tetragonal symmetry produced by direct-write assembly. Volume-averaged lattice strains in the Al{sub 2}O{sub 3} phase of the composite are measured by synchrotron X-ray diffraction for various uniaxial compression stresses up to -350MPa. Load transfer, found by diffraction to occur from the metal phase to the ceramic phase, is in general agreement with simple rule-of-mixture models and in better agreement with more complex, 3-D finite-element models that account for metal plasticity and details of the geometry of both phases. Spatially resolved diffractionmore » measurements show variations in load transfer at two different positions within the composite.« less

  3. A simplified method to reduce prosthetic misfit for a screw-retained, implant-supported complete denture using a luting technique and laser welding.

    PubMed

    Longoni, Salvatore; Sartori, Matteo; Davide, Roberto

    2004-06-01

    An important aim of implant-supported prostheses is to achieve a passive fit of the framework with the abutments to limit the amount of stress transfer to the bone-implant interface. An efficient and standardized technique is proposed. A definitive screw-retained, implant-supported complete denture was fabricated for an immediately loaded provisional screw-retained implant-supported complete denture. Precise fit was achieved by the use of industrial titanium components and the passivity, by an intraoral luting sequence and laser welding.

  4. Viscoelastic behavior and life-time predictions

    NASA Technical Reports Server (NTRS)

    Dillard, D. A.; Brinson, H. F.

    1985-01-01

    Fiber reinforced plastics were considered for many structural applications in automotive, aerospace and other industries. A major concern was and remains the failure modes associated with the polymer matrix which serves to bind the fibers together and transfer the load through connections, from fiber to fiber and ply to ply. An accelerated characterization procedure for prediction of delayed failures was developed. This method utilizes time-temperature-stress-moisture superposition principles in conjunction with laminated plate theory. Because failures are inherently nonlinear, the testing and analytic modeling for both moduli and strength is based upon nonlinear viscoelastic concepts.

  5. MODEL TESTS AND 3D ELASTIC FINITE ELEMENT ANALYSIS FOR STEEL PIPE PILES WITH WINGS IN STALLED IN SOIL CEMENT COLUMN

    NASA Astrophysics Data System (ADS)

    Tamai, Toshiyuki; Teramoto, Shuntarou; Kimura, Makoto

    Steel pipe piles with wings installed in soil cement column is a composite foundation of pile consisting of soil improvement with cement and steel pipe with wings. This type of pile shows higher vertical bearing capacity when compared to steel pipe piles that are installed without soil cement. It is thought the wings contribute to higher bearing capacity of this type of piles. The wings are also thought to play the role of structural unification of pile foundations and load transfer. In this study, model test and 3D elastic finite element analysis was carried out in order to elucidate the effect of wings on the structural unification of pile foundation and the load transfer mechanism. Firstly, the model test was carried out in order to grasp the influence of pile with and without wings, the shape of wings of the pile and the unconfined compression strength of the soil cement on the structural unification of the pile foundation. The numerical analysis of the model test was then carried out on the intermediate part of the pile foundation with wings and mathematical model developed. Finally load tran sfer mechanism was checked for the entire length of the pile through this mathematical model and the load sharing ratio of the wings and stress distribution occurring in the soil cement clarified. In addition, the effect of the wing interval on the structural unification of the pile foundation and load transfer was also checked and clarified.

  6. Smart-aggregate-based damage detection of fiber-reinforced-polymer-strengthened columns under reversed cyclic loading

    NASA Astrophysics Data System (ADS)

    Howser, Rachel; Moslehy, Yashar; Gu, Haichang; Dhonde, Hemant; Mo, Y. L.; Ayoub, Ashraf; Song, Gangbing

    2011-07-01

    Structural health monitoring is an important aspect of the maintenance of large civil infrastructures, especially for bridge columns in areas of high seismic activity. In this project, recently developed innovative piezoceramic-based sensors were utilized to perform the health monitoring of a shear-critical reinforced concrete (RC) bridge column subjected to reversed cyclic loading. After the column failed, it was wrapped with fiber reinforced polymer (FRP) sheets, commonly used to retrofit seismically damaged structures. The FRP-strengthened column was retested under the same reversed cyclic loading pattern. Innovative piezoceramic-based sensors, called 'smart aggregates', were utilized as transducers for health monitoring purposes. On the basis of the smart aggregates developed, an active-sensing approach and an impact-hammer-based approach were used to evaluate the health status of the RC column during the loading procedure. Wave transmission energy is attenuated by the existence of cracks during the loading procedure, and this attenuation phenomenon alters the curve of the transfer function between the actuator and sensor. To detect the damage occurrence and evaluate the damage severity, transfer function curves were compared with those obtained during the period of healthy status. A transfer-function-based damage index matrix was developed to demonstrate the damage severity at different locations. Experimental results verified the effectiveness of the smart aggregates in health monitoring of the FRP-strengthened column as well as the unstrengthened column. The experimental results show that the proposed smart-aggregate-based approach can successfully detect damage occurrence and evaluate its severity.

  7. Influence of the ambient temperature on the cooling efficiency of the high performance cooling device with thermosiphon effect

    NASA Astrophysics Data System (ADS)

    Nemec, Patrik; Malcho, Milan

    2018-06-01

    This work deal with experimental measurement and calculation cooling efficiency of the cooling device working with a heat pipe technology. The referred device in the article is cooling device capable transfer high heat fluxes from electric elements to the surrounding. The work contain description, working principle and construction of cooling device. The main factor affected the dissipation of high heat flux from electronic elements through the cooling device to the surrounding is condenser construction, its capacity and option of heat removal. Experimental part describe the measuring method cooling efficiency of the cooling device depending on ambient temperature in range -20 to 40°C and at heat load of electronic components 750 W. Measured results are compared with results calculation based on physical phenomena of boiling, condensation and natural convection heat transfer.

  8. Burner liner thermal-structural load modeling

    NASA Technical Reports Server (NTRS)

    Maffeo, R.

    1986-01-01

    The software package Transfer Analysis Code to Interface Thermal/Structural Problems (TRANCITS) was developed. The TRANCITS code is used to interface temperature data between thermal and structural analytical models. The use of this transfer module allows the heat transfer analyst to select the thermal mesh density and thermal analysis code best suited to solve the thermal problem and gives the same freedoms to the stress analyst, without the efficiency penalties associated with common meshes and the accuracy penalties associated with the manual transfer of thermal data.

  9. Analysis and design of an ultrahigh temperature hydrogen-fueled MHD generator

    NASA Technical Reports Server (NTRS)

    Moder, Jeffrey P.; Myrabo, Leik N.; Kaminski, Deborah A.

    1993-01-01

    A coupled gas dynamics/radiative heat transfer analysis of partially ionized hydrogen, in local thermodynamic equilibrium, flowing through an ultrahigh temperature (10,000-20,000 K) magnetohydrodynamic (MHD) generator is performed. Gas dynamics are modeled by a set of quasi-one-dimensional, nonlinear differential equations which account for friction, convective and radiative heat transfer, and the interaction between the ionized gas and applied magnetic field. Radiative heat transfer is modeled using nongray, absorbing-emitting 2D and 3D P-1 approximations which permit an arbitrary variation of the spectral absorption coefficient with frequency. Gas dynamics and radiative heat transfer are coupled through the energy equation and through the temperature- and density-dependent absorption coefficient. The resulting nonlinear elliptic problem is solved by iterative methods. Design of such MHD generators as onboard, open-cycle, electric power supplies for a particular advanced airbreathing propulsion concept produced an efficient and compact 128-MWe generator characterized by an extraction ratio of 35.5 percent, a power density of 10,500 MWe/cu m, and a specific (extracted) energy of 324 MJe/kg of hydrogen. The maximum wall heat flux and total wall heat load were 453 MW/sq m and 62 MW, respectively.

  10. Simultaneous Wireless Power Transfer and Data Communication Using Synchronous Pulse-Controlled Load Modulation.

    PubMed

    Mao, Shitong; Wang, Hao; Zhu, Chunbo; Mao, Zhi-Hong; Sun, Mingui

    2017-10-01

    Wireless Power Transfer (WPT) and wireless data communication are both important problems of research with various applications, especially in medicine. However, these two problems are usually studied separately. In this work, we present a joint study of both problems. Most medical electronic devices, such as smart implants, must have both a power supply to allow continuous operation and a communication link to pass information. Traditionally, separate wireless channels for power transfer and communication are utilized, which complicate the system structure, increase power consumption and make device miniaturization difficult. A more effective approach is to use a single wireless link with both functions of delivering power and passing information. We present a design of such a wireless link in which power and data travel in opposite directions. In order to aggressively miniaturize the implant and reduce power consumption, we eliminate the traditional multi-bit Analog-to-Digital Converter (ADC), digital memory and data transmission circuits all together. Instead, we use a pulse stream, which is obtained from the original biological signal, by a sigma-delta converter and an edge detector, to alter the load properties of the WPT channel. The resulting WPT signal is synchronized with the load changes therefore requiring no memory elements to record inter-pulse intervals. We take advantage of the high sensitivity of the resonant WPT to the load change, and the system dynamic response is used to transfer each pulse. The transient time of the WPT system is analyzed using the coupling mode theory (CMT). Our experimental results show that the memoryless approach works well for both power delivery and data transmission, providing a new wireless platform for the design of future miniaturized medical implants.

  11. Interfacial Stacks of Polymeric Nanofilms on Soft Biological Surfaces that Release Multiple Agents.

    PubMed

    Herron, Maggie; Schurr, Michael J; Murphy, Christopher J; McAnulty, Jonathan F; Czuprynski, Charles J; Abbott, Nicholas L

    2016-10-03

    We report a general and facile method that permits the transfer (stacking) of multiple independently fabricated and nanoscopically thin polymeric films, each containing a distinct bioactive agent, onto soft biomedically relevant surfaces (e.g., collagen-based wound dressings). By using polyelectrolyte multilayer films (PEMs) formed from poly(allyl amine hydrochloride) and poly(acrylic acid) as representative polymeric nanofilms and micrometer-thick water-soluble poly(vinyl alcohol) sacrificial films to stack the PEMs, we demonstrate that it is possible to create stacked polymeric constructs containing multiple bioactive agents (e.g., antimicrobial and antibiofilm agents) on soft and chemically complex surfaces onto which PEMs cannot be routinely transferred by stamping. We illustrate the characteristics and merits of the approach by fabricating stacks of Ga 3+ (antibiofilm agent)- and Ag + (antimicrobial agent)-loaded PEMs as prototypical examples of agent-containing PEMs and demonstrate that the stacked PEMs incorporate precise loadings of the agents and provide flexibility in terms of tuning release rates. Specifically, we show that simultaneous release of Ga 3+ and Ag + from the stacked PEMs on collagen-based wound dressings can lead to synergistic effects on bacteria, killing and dispersing biofilms formed by Pseudomonas aeruginosa (two strains: ATCC 27853 and MPAO1) at sufficiently low loadings of agents such that cytotoxic effects on mammalian cells are avoided. The approach is general (a wide range of bioactive agents other than Ga 3+ and Ag + can be incorporated into PEMs), and the modular nature of the approach potentially allows end-user functionalization of soft biological surfaces for programmed release of multiple bioactive agents.

  12. Homopolar machine for reversible energy storage and transfer systems

    DOEpatents

    Stillwagon, Roy E.

    1978-01-01

    A homopolar machine designed to operate as a generator and motor in reversibly storing and transferring energy between the machine and a magnetic load coil for a thermo-nuclear reactor. The machine rotor comprises hollow thin-walled cylinders or sleeves which form the basis of the system by utilizing substantially all of the rotor mass as a conductor thus making it possible to transfer substantially all the rotor kinetic energy electrically to the load coil in a highly economical and efficient manner. The rotor is divided into multiple separate cylinders or sleeves of modular design, connected in series and arranged to rotate in opposite directions but maintain the supply of current in a single direction to the machine terminals. A stator concentrically disposed around the sleeves consists of a hollow cylinder having a number of excitation coils each located radially outward from the ends of adjacent sleeves. Current collected at an end of each sleeve by sleeve slip rings and brushes is transferred through terminals to the magnetic load coil. Thereafter, electrical energy returned from the coil then flows through the machine which causes the sleeves to motor up to the desired speed in preparation for repetition of the cycle. To eliminate drag on the rotor between current pulses, the brush rigging is designed to lift brushes from all slip rings in the machine.

  13. Homopolar machine for reversible energy storage and transfer systems

    DOEpatents

    Stillwagon, Roy E.

    1981-01-01

    A homopolar machine designed to operate as a generator and motor in reversibly storing and transferring energy between the machine and a magnetic load coil for a thermo-nuclear reactor. The machine rotor comprises hollow thin-walled cylinders or sleeves which form the basis of the system by utilizing substantially all of the rotor mass as a conductor thus making it possible to transfer substantially all the rotor kinetic energy electrically to the load coil in a highly economical and efficient manner. The rotor is divided into multiple separate cylinders or sleeves of modular design, connected in series and arranged to rotate in opposite directions but maintain the supply of current in a single direction to the machine terminals. A stator concentrically disposed around the sleeves consists of a hollow cylinder having a number of excitation coils each located radially outward from the ends of adjacent sleeves. Current collected at an end of each sleeve by sleeve slip rings and brushes is transferred through terminals to the magnetic load coil. Thereafter, electrical energy returned from the coil then flows through the machine which causes the sleeves to motor up to the desired speed in preparation for repetition of the cycle. To eliminate drag on the rotor between current pulses, the brush rigging is designed to lift brushes from all slip rings in the machine.

  14. Experimental validation of new empirical models of the thermal properties of food products for safe shipping

    NASA Astrophysics Data System (ADS)

    Hamid, Hanan H.; Mitchell, Mark; Jahangiri, Amirreza; Thiel, David V.

    2018-04-01

    Temperature controlled food transport is essential for human safety and to minimise food waste. The thermal properties of food are important for determining the heat transfer during the transient stages of transportation (door opening during loading and unloading processes). For example, the temperature of most dairy products must be confined to a very narrow range (3-7 °C). If a predefined critical temperature is exceeded, the food is defined as spoiled and unfit for human consumption. An improved empirical model for the thermal conductivity and specific heat capacity of a wide range of food products was derived based on the food composition (moisture, fat, protein, carbohydrate and ash). The models that developed using linear regression analysis were compared with the published measured parameters in addition to previously published theoretical and empirical models. It was found that the maximum variation in the predicated thermal properties leads to less than 0.3 °C temperature change. The correlation coefficient for these models was 0.96. The t-Stat test ( P-value >0.99) demonstrated that the model results are an improvement on previous works. The transient heat transfer based on the food composition and the temperature boundary conditions was found for a Camembert cheese (short cylindrical shape) using a multiple dimension finite difference method code. The result was verified using the heat transfer today (HTT) educational software which is based on finite volume method. The core temperature rises from the initial temperature (2.7 °C) to the maximum safe temperature in ambient air (20.24 °C) was predicted to within about 35.4 ± 0.5 min. The simulation results agree very well ( +0.2 °C) with the measured temperature data. This improved model impacts on temperature estimation during loading and unloading the trucks and provides a clear direction for temperature control in all refrigerated transport applications.

  15. Development of an automated method to detect sitting pivot transfer phases using biomechanical variables: toward a standardized method

    PubMed Central

    2012-01-01

    Background Sitting pivot transfer (SPT) is one of the most important, but at the same time strenuous at the upper extremity, functional task for spinal cord injured individuals. In order to better teach this task to those individuals and to improve performance, a better biomechanical understanding during the different SPT phases is a prerequisite. However, no consensus has yet been reached on how to depict the different phases of the SPT. The definition of the phases of the SPT, along with the events characterizing these phases, will facilitate the interpretation of biomechanical outcome measures related to the performance of SPTs as well as strengthen the evidence generated across studies. Methods Thirty-five individuals with a spinal cord injury performed two SPTs between seats of similar height using their usual SPT technique. Kinematics and kinetics were recorded using an instrumented transfer assessment system. Based on kinetic and kinematic measurements, a relative threshold-based algorithm was developed to identify four distinct phases: pre-lift, upper arm loading, lift-pivot and post-lift phases. To determine the stability of the algorithm between the two SPTs, Student t-tests for dependent samples were performed on the absolute duration of each phase. Results The mean total duration of the SPT was 2.00 ± 0.49 s. The mean duration of the pre-lift, upper arm loading, lift-pivot and post-lift phases were 0.74 ± 0.29 s, 0.28 ± 0.13 s, 0.72 ± 0.24 s, 0.27 ± 0.14 s whereas their relative contributions represented approximately 35%, 15%, 35% and 15% of the overall SPT cycle, respectively. No significant differences were found between the trials (p = 0.480-0.891). Conclusion The relative threshold-based algorithm used to automatically detect the four distinct phases of the SPT, is rapid, accurate and repeatable. A quantitative and thorough description of the precise phases of the SPT is prerequisite to better interpret biomechanical findings and measure task performance. The algorithm could also become clinically useful to refine the assessment and training of SPTs. PMID:22305052

  16. Rational and Efficient Preparative Isolation of Natural Products by MPLC-UV-ELSD based on HPLC to MPLC Gradient Transfer.

    PubMed

    Challal, Soura; Queiroz, Emerson Ferreira; Debrus, Benjamin; Kloeti, Werner; Guillarme, Davy; Gupta, Mahabir Prashad; Wolfender, Jean-Luc

    2015-11-01

    In natural product research, the isolation of biomarkers or bioactive compounds from complex natural extracts represents an essential step for de novo identification and bioactivity assessment. When pure natural products have to be obtained in milligram quantities, the chromatographic steps are generally labourious and time-consuming. In this respect, an efficient method has been developed for the reversed-phase gradient transfer from high-performance liquid chromatography to medium-performance liquid chromatography for the isolation of pure natural products at the level of tens of milligrams from complex crude natural extracts. The proposed method provides a rational way to predict retention behaviour and resolution at the analytical scale prior to medium-performance liquid chromatography, and guarantees similar performances at both analytical and preparative scales. The optimisation of the high-performance liquid chromatography separation and system characterisation allows for the prediction of the gradient at the medium-performance liquid chromatography scale by using identical stationary phase chemistries. The samples were introduced in medium-performance liquid chromatography using a pressure-resistant aluminium dry load cell especially designed for this study to allow high sample loading while maintaining a maximum achievable flow rate for the separation. The method has been validated with a mixture of eight natural product standards. Ultraviolet and evaporative light scattering detections were used in parallel for a comprehensive monitoring. In addition, post-chromatographic mass spectrometry detection was provided by high-throughput ultrahigh-performance liquid chromatography time-of-flight mass spectrometry analyses of all fractions. The processing of all liquid chromatography-mass spectrometry data in the form of an medium-performance liquid chromatography x ultra high-performance liquid chromatography time-of-flight mass spectrometry matrix enabled an efficient localisation of the compounds of interest in the generated fractions. The methodology was successfully applied for the separation of three different plant extracts that contain many diverse secondary metabolites. The advantages and limitations of this approach and the theoretical chromatographic background that rules such as liquid chromatography gradient transfer are presented from a practical viewpoint. Georg Thieme Verlag KG Stuttgart · New York.

  17. The mechanism of force transference in feet of children ages two to six.

    PubMed

    Hu, Mingyu; Zhou, Nan; Xu, Bo; Chen, Wuyong; Wu, Jianxin; Zhou, Jin

    2017-05-01

    The aim of this study was to design an algorithm to quantify the plantar force transference of children from ages 2-6. In total, 319 healthy children without abnormal gait patterns, foot deformities or injuries, able to walk independently, and with normal BMIs were recruited, and their plantar force distributions were measured. Their plantar areas were divided into ten parts: the hallux, toes #2-5, the first to fifth metatarsal heads (1st-5th MTH), the mid-foot (MF), medial heel (MH) and lateral heel (LH), in which a relative force-time integral (FTIrel) (%) was calculated. Our results show that the FTIrel was significantly transferred along either the transverse or longitudinal arches. The middle of the forefoot and the toe areas were the two main loading regions in children aged 2-3, and posterior to anterior FTIrel shifting was typical. However, anterior to posterior and lateral to medial FTI transferences were found in children aged 5-6, and major loading was found in the heel area. Further, loading in the mid-foot varied with the child's development and was observed to tend to decrease over time. Overall, according to the algorithm designed in this study, these results demonstrated that the development of the arches, both in transverse and longitudinal directions, had already begun in early stages of toddlerhood. Meanwhile, the arches were an important attractor engaged in the windlass mechanism while walking, and they played a major role as bridges to promote posterior to anterior and medial to lateral force transference. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Cognitive Load Theory--Sometimes Less Is More

    ERIC Educational Resources Information Center

    Taylor, Cody

    2013-01-01

    The following paper represents review of the literature examining the current research related to cognitive load theory and more specifically the negative aspects of the redundant on-screen text. The authors describe working and long-term memory and how both factor into human learning through the facilitation of knowledge transfer. Limited working…

  19. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... instructions for initial start-up and basic operating adjustments. (b) Check the dynamometer torque measurement... transfer standard may be used to verify the torque measurement system. (1) The master load-cell and read... master load-cell for each in-use range used. (5) The in-use torque measurement must be within 2 percent...

  20. Hierarchical polymerized high internal phase emulsions synthesized from surfactant-stabilized emulsion templates.

    PubMed

    Wong, Ling L C; Villafranca, Pedro M Baiz; Menner, Angelika; Bismarck, Alexander

    2013-05-21

    In building construction, structural elements, such as lattice girders, are positioned specifically to support the mainframe of a building. This arrangement provides additional structural hierarchy, facilitating the transfer of load to its foundation while keeping the building weight down. We applied the same concept when synthesizing hierarchical open-celled macroporous polymers from high internal phase emulsion (HIPE) templates stabilized by varying concentrations of a polymeric non-ionic surfactant from 0.75 to 20 w/vol %. These hierarchical poly(merized)HIPEs have multimodally distributed pores, which are efficiently arranged to enhance the load transfer mechanism in the polymer foam. As a result, hierarchical polyHIPEs produced from HIPEs stabilized by 5 vol % surfactant showed a 93% improvement in Young's moduli compared to conventional polyHIPEs produced from HIPEs stabilized by 20 vol % of surfactant with the same porosity of 84%. The finite element method (FEM) was used to determine the effect of pore hierarchy on the mechanical performance of porous polymers under small periodic compressions. Results from the FEM showed a clear improvement in Young's moduli for simulated hierarchical porous geometries. This methodology could be further adapted as a predictive tool to determine the influence of hierarchy on the mechanical properties of a range of porous materials.

  1. Thin Film Catalyst Layers for Direct Methanol Fuel Cells

    NASA Technical Reports Server (NTRS)

    Witham, C. K.; Chun, W.; Ruiz, R.; Valdez, T. I.; Narayanan, S. R.

    2000-01-01

    One of the primary obstacles to the widespread use of the direct methanol fuel cell (DMFC) is the high cost of the catalyst. Therefore, reducing the catalyst loading well below the current level of 8-12 mg/cm 2 would be important to commercialization. The current methods for preparation of catalyst layers consisting of catalyst, ionomer and sometimes a hydrophobic additive are applied by either painting, spraying, decal transfer or screen printing processes. Sputter deposition is a coating technique widely used in manufacturing and therefore particularly attractive. In this study we have begun to explore sputtering as a method for catalyst deposition. Present experiments focus on Pt-Ru catalyst layers for the anode.

  2. MODELING FUNCTIONALLY GRADED INTERPHASE REGIONS IN CARBON NANOTUBE REINFORCED COMPOSITES

    NASA Technical Reports Server (NTRS)

    Seidel, G. D.; Lagoudas, D. C.; Frankland, S. J. V.; Gates, T. S.

    2006-01-01

    A combination of micromechanics methods and molecular dynamics simulations are used to obtain the effective properties of the carbon nanotube reinforced composites with functionally graded interphase regions. The multilayer composite cylinders method accounts for the effects of non-perfect load transfer in carbon nanotube reinforced polymer matrix composites using a piecewise functionally graded interphase. The functional form of the properties in the interphase region, as well as the interphase thickness, is derived from molecular dynamics simulations of carbon nanotubes in a polymer matrix. Results indicate that the functional form of the interphase can have a significant effect on all the effective elastic constants except for the effective axial modulus for which no noticeable effects are evident.

  3. Full-scale fatigue tests of CX-100 wind turbine blades. Part II: analysis

    NASA Astrophysics Data System (ADS)

    Taylor, Stuart G.; Jeong, Hyomi; Jang, Jae Kyeong; Park, Gyuhae; Farinholt, Kevin M.; Todd, Michael D.; Ammerman, Curtt M.

    2012-04-01

    This paper presents the initial analysis results of several structural health monitoring (SHM) methods applied to two 9- meter CX-100 wind turbine blades subjected to fatigue loading at the National Renewable Energy Laboratory's (NREL) National Wind Technology Center (NWTC). The first blade was a pristine blade, manufactured to standard CX-100 design specifications. The second blade was manufactured for the University of Massachusetts, Lowell (UMass), with intentional simulated defects within the fabric layup. Each blade was instrumented with a variety of sensors on its surface. The blades were subject to harmonic excitation at their first natural frequency with steadily increasing loading until ultimately reaching failure. Data from the sensors were collected between and during fatigue loading sessions. The data were measured at multi-scale frequency ranges using a variety of data acquisition equipment, including off-the-shelf systems and prototype data acquisition hardware. The data were analyzed to identify fatigue damage initiation and to assess damage progression. Modal response, diffuse wave-field transfer functions in time and frequency domains, and wave propagation methods were applied to assess the condition of the turbine blade. The analysis methods implemented were evaluated in conjunction with hardware-specific performance for their efficacy in enabling the assessment of damage progression in the blade. The results of this assessment will inform the selection of specific data to be collected and analysis methods to be implemented for a CX-100 flight test to be conducted in collaboration with Sandia National Laboratory at the U.S. Department of Agriculture's (USDA) Conservation and Production Research Laboratory (CPRL) in Bushland, Texas.

  4. Effect of Helmet Pads on the Load Transfer to Head under Blast Loadings

    DTIC Science & Technology

    2015-06-01

    0.15 0.2 X  St re ss  (K Pa ) Time (ms) Foam  L Foam  M Foam  R 6 its much smaller acoustic impedance. The stress amplitude increases as it reflects...understood for the helmet/ foam pads. The pads between the helmet and head can not only absorb energy, but also produce more comfort to the head. The gap...to investigate the effects of foam pads on the load transmitted to the head under blast loading. The ALE module in the commercial code, LSDYNA was

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

    Ronold, K.O.; Nielsen, N.J.R.; Tura, F.

    This paper demonstrates how a structural reliability method can be applied as a rational means to analyze free spans of submarine pipelines with respect to failure in ultimate loading, and to establish partial safety factors for design of such free spans against this failure mode. It is important to note that the described procedure shall be considered as an illustration of a structural reliability methodology, and that the results do not represent a set of final design recommendations. A scope of design cases, consisting of a number of available site-specific pipeline spans, is established and is assumed representative for themore » future occurrence of submarine pipeline spans. Probabilistic models for the wave and current loading and its transfer to stresses in the pipe wall of a pipeline span is established together with a stochastic representation of the material resistance. The event of failure in ultimate loading is considered as based on a limit state which is reached when the maximum stress over the design life of the pipeline exceeds the yield strength of the pipe material. The yielding limit state is considered an ultimate limit state (ULS).« less

  6. Rock-bed thermocline storage: A numerical analysis of granular bed behavior and interaction with storage tank

    NASA Astrophysics Data System (ADS)

    Sassine, Nahia; Donzé, Frédéric-Victor; Bruch, Arnaud; Harthong, Barthélemy

    2017-06-01

    Thermal Energy Storage (TES) systems are central elements of various types of power plants operated using renewable energy sources. Packed bed TES can be considered as a cost-effective solution in concentrated solar power plants (CSP). Such a device is made up of a tank filled with a granular bed through which heat-transfer fluid circulates. However, in such devices, the tank might be subjected to catastrophic failure induced by a mechanical phenomenon known as thermal ratcheting. Thermal stresses are accumulated during cycles of loading and unloading until the failure happens. This paper aims at studying the evolution of tank wall stresses over granular bed thermal cycles, taking into account both thermal and mechanical loads, with a numerical model based on the discrete element method (DEM). Simulations were performed to study two different thermal configurations: (i) the tank is heated homogenously along its height or (ii) with a vertical gradient of temperature. Then, the resulting loading stresses applied on the tank are compared as well the response of the internal granular material.

  7. Intra-ocular lens optical changes resulting from the loading of dexamethasone.

    PubMed

    Artigas, José M; García-Domene, M Carmen; Navea, Amparo; Botella, Pablo; Fernández, Eduardo

    2017-10-01

    To study the optical changes on hydrogel-silicone intraocular lenses (IOLs) resulting from loading them with dexamethasone. We used prototype hydrogel(pHEMA)-silicone IOLs and loaded the matrices with an anti-inflammatory drug (dexamethasone). The optical properties we analyzed experimentally were a) modulation transfer function (MTF); b) spectral transmission; c) diopter power. These determinations were performed on drug-loaded IOLs, IOLs that had released the drug, and IOLs that had not been drug-loaded. Loading a hydrogel-silicone IOL with dexamethasone results in impairment of its optical qualities, in particular its MTF and spectral transmission, but not dioptric power. However, once the drug has been released, it almost recovers its initial optical properties.

  8. Intra-ocular lens optical changes resulting from the loading of dexamethasone

    PubMed Central

    Artigas, José M.; García-Domene, M. Carmen; Navea, Amparo; Botella, Pablo; Fernández, Eduardo

    2017-01-01

    To study the optical changes on hydrogel-silicone intraocular lenses (IOLs) resulting from loading them with dexamethasone. We used prototype hydrogel(pHEMA)-silicone IOLs and loaded the matrices with an anti-inflammatory drug (dexamethasone). The optical properties we analyzed experimentally were a) modulation transfer function (MTF); b) spectral transmission; c) diopter power. These determinations were performed on drug-loaded IOLs, IOLs that had released the drug, and IOLs that had not been drug-loaded. Loading a hydrogel-silicone IOL with dexamethasone results in impairment of its optical qualities, in particular its MTF and spectral transmission, but not dioptric power. However, once the drug has been released, it almost recovers its initial optical properties. PMID:29082089

  9. Study of superconducting magnetic bearing applicable to the flywheel energy storage system that consist of HTS-bulks and superconducting-coils

    NASA Astrophysics Data System (ADS)

    Seino, Hiroshi; Nagashima, Ken; Tanaka, Yoshichika; Nakauchi, Masahiko

    2010-06-01

    The Railway Technical Research Institute conducted a study to develop a superconducting magnetic bearing applicable to the flywheel energy-storage system for railways. In the first step of the study, the thrust rolling bearing was selected for application, and adopted liquid-nitrogen-cooled HTS-bulk as a rotor, and adopted superconducting coil as a stator for the superconducting magnetic bearing. Load capacity of superconducting magnetic bearing was verified up to 10 kN in the static load test. After that, rotation test of that approximately 5 kN thrust load added was performed with maximum rotation of 3000rpm. In the results of bearing rotation test, it was confirmed that position in levitation is able to maintain with stability during the rotation. Heat transfer properties by radiation in vacuum and conductivity by tenuous gas were basically studied by experiment by the reason of confirmation of rotor cooling method. The experimental result demonstrates that the optimal gas pressure is able to obtain without generating windage drag. In the second stage of the development, thrust load capacity of the bearing will be improved aiming at the achievement of the energy capacity of a practical scale. In the static load test of the new superconducting magnetic bearing, stable 20kN-levitation force was obtained.

  10. Uncertainty Of Stream Nutrient Transport Estimates Using Random Sampling Of Storm Events From High Resolution Water Quality And Discharge Data

    NASA Astrophysics Data System (ADS)

    Scholefield, P. A.; Arnscheidt, J.; Jordan, P.; Beven, K.; Heathwaite, L.

    2007-12-01

    The uncertainties associated with stream nutrient transport estimates are frequently overlooked and the sampling strategy is rarely if ever investigated. Indeed, the impact of sampling strategy and estimation method on the bias and precision of stream phosphorus (P) transport calculations is little understood despite the use of such values in the calibration and testing of models of phosphorus transport. The objectives of this research were to investigate the variability and uncertainty in the estimates of total phosphorus transfers at an intensively monitored agricultural catchment. The Oona Water which is located in the Irish border region, is part of a long term monitoring program focusing on water quality. The Oona Water is a rural river catchment with grassland agriculture and scattered dwelling houses and has been monitored for total phosphorus (TP) at 10 min resolution for several years (Jordan et al, 2007). Concurrent sensitive measurements of discharge are also collected. The water quality and discharge data were provided at 1 hour resolution (averaged) and this meant that a robust estimate of the annual flow weighted concentration could be obtained by simple interpolation between points. A two-strata approach (Kronvang and Bruhn, 1996) was used to estimate flow weighted concentrations using randomly sampled storm events from the 400 identified within the time series and also base flow concentrations. Using a random stratified sampling approach for the selection of events, a series ranging from 10 through to the full 400 were used, each time generating a flow weighted mean using a load-discharge relationship identified through log-log regression and monte-carlo simulation. These values were then compared to the observed total phosphorus concentration for the catchment. Analysis of these results show the impact of sampling strategy, the inherent bias in any estimate of phosphorus concentrations and the uncertainty associated with such estimates. The estimates generated using the full time series underestimate the flow weighted mean concentration of total phosphorus. This work compliments other contemporary work in the area of load estimation uncertainty in the UK (Johnes, 2007). Johnes P,J. 2007, Uncertainties in annual riverine phosphorus load estimation: Impact of load estimation methodology, sampling frequency, baseflow index and catchment population density, Journal of hydrology 332 (1- 2): 241-258 Jordan, P., Arnscheidt, J., McGrogan, H & McCormick, S., 2007. Characterising phosphorus transfers in rural transfers using a continuous bank-side analyser. Hydrology and Earth System Science 11, 372-381 Kronvang B & Bruhn, A. J, 1996. Choice of sampling strategy and estimation method for calculating nitrogen and phosphorus transport in small lowland streams , Hydrological processes 10 (11): 1483-1501

  11. Compaction-Based Deformable Terrain Model as an Interface for Real-Time Vehicle Dynamics Simulations

    DTIC Science & Technology

    2013-04-16

    to vehicular loads, and the resulting visco-elastic-plastic stress/strain on the affected soil volume. Pedo transfer functions allow for the...resulting visco-elastic-plastic stress/strain on the affected soil volume. Pedo transfer functions allow for the calculation of the soil mechanics model

  12. Increasing the thermal conductivity of silicone based fluids using carbon nanofibers

    NASA Astrophysics Data System (ADS)

    Vales-Pinzon, C.; Vega-Flick, A.; Pech-May, N. W.; Alvarado-Gil, J. J.; Medina-Esquivel, R. A.; Zambrano-Arjona, M. A.; Mendez-Gamboa, J. A.

    2016-11-01

    Heat transfer in silicone fluids loaded with high thermal conductivity carbon nanofibers was studied using photoacoustics and thermal wave resonator cavity. It is shown that heat transport depends strongly on volume fraction of carbon nanofibers; in particular, a low loading percentage is enough to obtain significant changes in thermal conductivity. Theoretical models were used to determine how heat transfer is affected by structural formations in the composite, such as packing fraction and aspect ratio (form factor) of carbon nanofiber agglomerates in the high viscosity fluid matrix. Our results may find practical applications in systems, in which the carbon nanofibers can facilitate heat dissipation in the electronic devices.

  13. Cationized pullulan 3D matrices as new materials for gene transfer.

    PubMed

    San Juan, Aurélie; Hlawaty, Hanna; Chaubet, Frédéric; Letourneur, Didier; Feldman, Laurent J

    2007-08-01

    This study deals with the development of a novel biocompatible cationized pullulan three-dimensional matrix for gene delivery. A water-soluble cationic polysaccharide, diethylaminoethyl-pullulan (DEAE-pullulan), was first synthesized and characterized. Fluorescence quenching and gel retardation assays evidenced the complexation in solution of DNA with DEAE-pullulan, but not with neutral pullulan. On cultured smooth muscle cells (SMCs) incubated with DEAE-pullulan and a plasmid vector expressing a secreted form of alkaline phosphatase (pSEAP), SEAP activity was 150-fold higher than with pSEAP alone or pSEAP with neutral pullulan. DEAE-pullulan was then chemically crosslinked using phosphorus oxychloride. The resulting matrices were obtained in less than a minute and molded as discs of 12 mm diameter and 2 mm thickness. Such DEAE-pullulan 3D matrices were loaded with up to 50 microg of plasmid DNA, with a homogeneous plasmid loading observed with YOYO-1 fluorescence staining. Moreover, the DEAE-pullulan matrix was shown to protect pSEAP from DNase I degradation. Incubation of cultured SMCs with pSEAP-loaded DEAE-pullulan matrices resulted in significant gene transfer without cell toxicity. This study suggests that these cationized pullulan 3D matrices could be useful biomaterials for local gene transfer.

  14. Experimental Investigation of two-phase nitrogen Cryo transfer line

    NASA Astrophysics Data System (ADS)

    Singh, G. K.; Nimavat, H.; Panchal, R.; Garg, A.; Srikanth, GLN; Patel, K.; Shah, P.; Tanna, V. L.; Pradhan, S.

    2017-02-01

    A 6-m long liquid nitrogen based cryo transfer line has been designed, developed and tested at IPR. The test objectives include the thermo-hydraulic characteristics of Cryo transfer line under single phase as well as two phase flow conditions. It is always easy in experimentation to investigate the thermo-hydraulic parameters in case of single phase flow of cryogen but it is real challenge when one deals with the two phase flow of cryogen due to availibity of mass flow measurements (direct) under two phase flow conditions. Established models have been reported in the literature where one of the well-known model of Lockhart-Martenelli relationship has been used to determine the value of quality at the outlet of Cryo transfer line. Under homogenous flow conditions, by taking the ratio of the single-phase pressure drop and the two-phase pressure drop, we estimated the quality at the outlet. Based on these equations, vapor quality at the outlet of the transfer line was predicted at different heat loads. Experimental rresults shown that from inlet to outlet, there is a considerable increment in the pressure drop and vapour quality of the outlet depending upon heat load and mass flow rate of nitrogen flowing through the line.

  15. Multi-Scale Modeling of an Integrated 3D Braided Composite with Applications to Helicopter Arm

    NASA Astrophysics Data System (ADS)

    Zhang, Diantang; Chen, Li; Sun, Ying; Zhang, Yifan; Qian, Kun

    2017-10-01

    A study is conducted with the aim of developing multi-scale analytical method for designing the composite helicopter arm with three-dimensional (3D) five-directional braided structure. Based on the analysis of 3D braided microstructure, the multi-scale finite element modeling is developed. Finite element analysis on the load capacity of 3D five-directional braided composites helicopter arm is carried out using the software ABAQUS/Standard. The influences of the braiding angle and loading condition on the stress and strain distribution of the helicopter arm are simulated. The results show that the proposed multi-scale method is capable of accurately predicting the mechanical properties of 3D braided composites, validated by the comparison the stress-strain curves of meso-scale RVCs. Furthermore, it is found that the braiding angle is an important factor affecting the mechanical properties of 3D five-directional braided composite helicopter arm. Based on the optimized structure parameters, the nearly net-shaped composite helicopter arm is fabricated using a novel resin transfer mould (RTM) process.

  16. Fatigue cracking in road pavement

    NASA Astrophysics Data System (ADS)

    Mackiewicz, P.

    2018-05-01

    The article presents the problem of modelling fatigue phenomena occurring in the road pavement. The example of two selected pavements shows the changes occurring under the influence of the load in different places of the pavement layers. Attention is paid to various values of longitudinal and transverse strains generated at the moment of passing the wheel on the pavement. It was found that the key element in the crack propagation analysis is the method of transferring the load to the pavement by the tire and the strain distribution in the pavement. During the passage of the wheel in the lower layers of the pavement, a complex stress state arises. Then vertical, horizontal and tangent stresses with various values appear. The numerical analyses carried out with the use of finite element methods allowed to assess the strain and stress changes occurring in the process of cracking road pavement. It has been shown that low-thickness pavements are susceptible to fatigue cracks arising "bottom to top", while pavements thicker are susceptible to "top to bottom" cracks. The analysis of the type of stress allowed to determine the cracking mechanism.

  17. High-speed thermal cycling system and method of use

    DOEpatents

    Hansen, A.D.A.; Jaklevic, J.M.

    1996-04-16

    A thermal cycling system and method of use are described. The thermal cycling system is based on the circulation of temperature-controlled water directly to the underside of thin-walled polycarbonate plates. The water flow is selected from a manifold fed by pumps from heated reservoirs. The plate wells are loaded with typically 15-20 microliters of reagent mix for the PCR process. Heat transfer through the thin polycarbonate is sufficiently rapid that the contents reach thermal equilibrium with the water in less than 15 seconds. Complete PCR amplification runs of 40 three-step cycles have been performed in as little as 14.5 minutes, with the results showing substantially enhanced specificity compared to conventional technology requiring run times in excess of 100 minutes. The plate clamping station is designed to be amenable to robotic loading and unloading of the system. It includes a heated lid, thus eliminating the need for mineral oil overlay of the reactants. The present system includes three or more plate holder stations, fed from common reservoirs but operating with independent switching cycles. The system can be modularly expanded. 13 figs.

  18. High-speed thermal cycling system and method of use

    DOEpatents

    Hansen, Anthony D. A.; Jaklevic, Joseph M.

    1996-01-01

    A thermal cycling system and method of use are described. The thermal cycling system is based on the-circulation of temperature-controlled water directly to the underside of thin-walled polycarbonate microtiter plates. The water flow is selected from a manifold fed by pumps from heated reservoirs. The plate wells are loaded with typically 15-20 .mu.l of reagent mix for the PCR process. Heat transfer through the thin polycarbonate is sufficiently rapid that the contents reach thermal equilibrium with the water in less than 15 seconds. Complete PCR amplification runs of 40 three-step cycles have been performed in as little as 14.5 minutes, with the results showing substantially enhanced specificity compared to conventional technology requiring run times in excess of 100 minutes. The plate clamping station is designed to be amenable to robotic loading and unloading of the system. It includes a heated lid, thus eliminating the need for mineral oil overlay of the reactants. The present system includes three or more plate holder stations, fed from common reservoirs but operating with independent switching cycles. The system can be modularly expanded.

  19. Numerical study of effect of elastomeric stress absorbers on stress reduction in bone-dental implant interface.

    PubMed

    Mehdi, Ghalem; Belarbi, Abderrahmane; Mansouri, Bensmaine; Azari, Zitouni

    2015-01-01

    This paper focused on optimal stress distribution in the mandibular bone surrounding a dental implant and is devoted to the development of a modified Osteoplant® implant type in order to minimize stress concentration in the bone-implant interface. This study investigated 0.4 mm thick layers of two elastomeric stress barriers incorporated into the dental implant using 3-D finite element analysis. Overall, this proposed implant provoked lower load transfer in bone-implant interface due to the effect of the elastomers as stress absorbers. The stress level in the bone was reduced between 28% and 42% for three load cases: 75 N, 60 N and 27 N in corono-apical, linguo-buccal and disto-mesial direction, respectively. The proposed model provided an acceptable solution for load transfer reduction to the mandible. This investigation also permitted to choose how to incorporate two elastomers into the Osteoplant® implant system.

  20. Analytical and experimental investigation of fatigue in lap joints

    NASA Astrophysics Data System (ADS)

    Swenson, Daniel V.; Chih-Chien, Chia; Derber, Thomas G.

    A finite element model is presented that can simulate crack growth in layered structures such as lap joints. The layers can be joined either by rivets or adhesives. The crack is represented discretely in the mesh, and automatic remeshing is performed as the crack grows. Because of the connections between the layers, load is transferred to the uncracked layer as the crack grows. This reduces the stress intensity and slows the crack growth rate. The model is used to analyze tests performed on a section of a wing spanwise lap joint. The crack was initiated at a rivet and grown under constant amplitude cyclic loads. Both experimentally observed crack growth rates and the analysis show the retardation that occurs as a result of load transfer between layers. A good correlation is obtained between predicted and observed crack growth rates for the fullly developed through-thickness crack.

  1. Wrinkled Few-Layer Graphene as Highly Efficient Load Bearer.

    PubMed

    Androulidakis, Charalampos; Koukaras, Emmanuel N; Rahova, Jaroslava; Sampathkumar, Krishna; Parthenios, John; Papagelis, Konstantinos; Frank, Otakar; Galiotis, Costas

    2017-08-09

    Multilayered graphitic materials are not suitable as load-bearers due to their inherent weak interlayer bonding (for example, graphite is a solid lubricant in certain applications). This situation is largely improved when two-dimensional (2D) materials such as a monolayer (SLG) graphene are employed. The downside in these cases is the presence of thermally or mechanically induced wrinkles which are ubiquitous in 2D materials. Here we set out to examine the effect of extensive large wavelength/amplitude wrinkling on the stress transfer capabilities of exfoliated simply supported graphene flakes. Contrary to common belief we present clear evidence that this type of "corrugation" enhances the load-bearing capacity of few-layer graphene as compared to "flat" specimens. This effect is the result of the significant increase of the graphene/polymer interfacial shear stress per increment of applied strain due to wrinkling and paves the way for designing affordable graphene composites with highly improved stress-transfer efficiency.

  2. Effects of the air–steam mixture on the permeability of damaged concrete

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

    Medjigbodo, Sonagnon; Darquennes, Aveline; Aubernon, Corentin

    Massive concrete structures such as the containments of nuclear power plant must maintain their tightness at any circumstances to prevent the escape of radioactive fission products into the environment. In the event of an accident like a Loss of Coolant Accident (LOCA), the concrete wall is submitted to both hydric and mechanical loadings. A new experimental device reproducing these extreme conditions (water vapor transfer, 140 °C and 5 bars) is developed in the GeM Laboratory to determine the effect of the saturation degree, the mechanical loading and the flowing fluid type on the concrete transfer properties. The experimental tests showmore » that the previous parameters significantly affect the concrete permeability and the gas leakage rate. Their evolution as a function of the mechanical loading is characterized by two phases that are directly related to concrete microstructure and crack development.« less

  3. Steady internal flow and aerodynamic loads analysis of shuttle thermal protection system

    NASA Technical Reports Server (NTRS)

    Petley, D. H.; Alexander, W., Jr.; Ivey, G. W., Jr.; Kerr, P. A.

    1984-01-01

    An analytical model for calculation of ascent steady state tile loading was developed and validated with wind tunnel data. The analytical model is described and results are given. Results are given for loading due to shocks and skin friction. The analysis included calculation of internal flow (porous media flow and channel flow) to obtain pressures and integration of the pressures to obtain forces and moments on an insulation tile. A heat transfer program was modified by using analogies between heat transfer and fluid flow so that it could be used for internal flow calculation. The type of insulation tile considered was undensified reusable surface insulation (RSI) without gap fillers, and the location studied was the lower surface of the orbiter. Force and moment results are reported for parameter variations on surface pressure distribution, gap sizes, insulation permeability, and tile thickness.

  4. Influence of matrix attachment installation load on movement and resultant forces in implant overdentures.

    PubMed

    Goto, Takaharu; Nagao, Kan; Ishida, Yuichi; Tomotake, Yoritoki; Ichikawa, Tetsuo

    2015-02-01

    This in vitro study investigated the effect of attachment installation conditions on the load transfer and denture movements of implant overdentures, and aims to clarify the differences among the three types of attachments, namely ball, Locator, and magnet attachments. Three types of attachments, namely ball, Locator, and magnetic attachments were used. An acrylic resin mandibular edentulous model with two implants placed in the bilateral canine regions and removable overdenture were prepared. The two implants and bilateral molar ridges were connected to three-axis load-cell transducers, and a universal testing machine was used to apply a 50 N vertical force to each site of the occlusal table in the first molar region. The denture movement was measured using a G(2) motion sensor. Three installation conditions, namely, the application of 0, 50, and 100 N loads were used to install each attachment on the denture base. The load transfer and denture movement were then evaluated. The resultant force decreased with increasing installation load for all attachments. In particular, the resultant force on implants on the loading side of the Locator attachment significantly decreased when the installation load was increased from 0 to 50 N, and that for magnetic attachment significantly decreased when the installation load was increased from 50 to 100 N. For the residual ridges on the loading side, the direction of the forces for all attachments changed to downward with increasing installation load. Furthermore, the yaw Euler angle increased with increasing installation load for the magnetic attachment. Subject to the limitations of this study, the use of any installation load greater than 0 N is recommended for the installation of ball and Locator attachments on a denture base. Regarding magnetic attachments, our results also recommend installation on a denture base using any installation load greater than 0 N, and suggest that the resultant force acting on the implant can be decreased by increasing the installation load; however, a large installation load of 100 N should be avoided when installing the attachment on the denture base to avoid increasing the denture movement. © 2014 by the American College of Prosthodontists.

  5. Application of Novel Lateral Tire Force Sensors to Vehicle Parameter Estimation of Electric Vehicles

    PubMed Central

    Nam, Kanghyun

    2015-01-01

    This article presents methods for estimating lateral vehicle velocity and tire cornering stiffness, which are key parameters in vehicle dynamics control, using lateral tire force measurements. Lateral tire forces acting on each tire are directly measured by load-sensing hub bearings that were invented and further developed by NSK Ltd. For estimating the lateral vehicle velocity, tire force models considering lateral load transfer effects are used, and a recursive least square algorithm is adapted to identify the lateral vehicle velocity as an unknown parameter. Using the estimated lateral vehicle velocity, tire cornering stiffness, which is an important tire parameter dominating the vehicle’s cornering responses, is estimated. For the practical implementation, the cornering stiffness estimation algorithm based on a simple bicycle model is developed and discussed. Finally, proposed estimation algorithms were evaluated using experimental test data. PMID:26569246

  6. Full-field fabric stress mapping by micro Raman spectroscopy in a yarn push-out test.

    PubMed

    Lei, Z K; Qin, F Y; Fang, Q C; Bai, R X; Qiu, W; Chen, X

    2018-02-01

    The full-field stress distribution of a two-dimensional plain fabric was mapped using micro Raman spectroscopy (MRS) through a novel yarn push-out test, simulating a quasi-static projectile impact on the fabric. The stress-strain relationship for a single yarn was established using a digital image correlation method in a single-yarn tensile test. The relationship between Raman peak shift and aramid Kevlar 49 yarn stress was established using MRS in a single-yarn tensile test. An out-of-plane loading test was conducted on an aramid Kevlar 49 plain fabric, and the yarn stress was measured using MRS. From the full-field fabric stress distribution, it can be observed that there is a cross-shaped distribution of high yarn stress; this result would be helpful in further studies on load transfer on a fabric during a projectile impact.

  7. 40 CFR 63.11132 - What definitions apply to this subpart?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... unloading gasoline, or which has loaded or unloaded gasoline on the immediately previous load. Gasoline... whose discharge is no more than the applicable distance specified in § 63.11117(b) from the bottom of... are transferred to the gasoline cargo tank being unloaded. Vapor-tight means equipment that allows no...

  8. 46 CFR 153.1065 - Sodium chlorate solutions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Sodium chlorate solutions. 153.1065 Section 153.1065... Procedures § 153.1065 Sodium chlorate solutions. (a) No person may load sodium chlorate solutions into a... before loading. (b) The person in charge of cargo transfer shall make sure that spills of sodium chlorate...

  9. 46 CFR 153.1065 - Sodium chlorate solutions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Sodium chlorate solutions. 153.1065 Section 153.1065... Procedures § 153.1065 Sodium chlorate solutions. (a) No person may load sodium chlorate solutions into a... before loading. (b) The person in charge of cargo transfer shall make sure that spills of sodium chlorate...

  10. 46 CFR 153.1065 - Sodium chlorate solutions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Sodium chlorate solutions. 153.1065 Section 153.1065... Procedures § 153.1065 Sodium chlorate solutions. (a) No person may load sodium chlorate solutions into a... before loading. (b) The person in charge of cargo transfer shall make sure that spills of sodium chlorate...

  11. 40 CFR 86.333-79 - Dynamometer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... basic operating adjustments. (b) Check the dynamometer torque measurement for each range used by the... or transfer standard may be used to verify the in-use torque measurement system. (1) The master load... master load-cell for each in-use range used. (5) The in-use torque measurement must be within 2 percent...

  12. 40 CFR 86.333-79 - Dynamometer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... basic operating adjustments. (b) Check the dynamometer torque measurement for each range used by the... or transfer standard may be used to verify the in-use torque measurement system. (1) The master load... master load-cell for each in-use range used. (5) The in-use torque measurement must be within 2 percent...

  13. 40 CFR 86.333-79 - Dynamometer calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... basic operating adjustments. (b) Check the dynamometer torque measurement for each range used by the... or transfer standard may be used to verify the in-use torque measurement system. (1) The master load... master load-cell for each in-use range used. (5) The in-use torque measurement must be within 2 percent...

  14. Test results from large wing and fuselage panels

    NASA Technical Reports Server (NTRS)

    Madan, Ram C.; Voldman, Mike

    1993-01-01

    This paper presents the first results in an assessment of the strength, stiffness, and damage tolerance of stiffened wing and fuselage subcomponents. Under this NASA funded program, 10 large wing and fuselage panels, variously fabricated by automated tow placement and dry-stitched preform/resin transfer molding, are to be tested. The first test of an automated tow placement six-longeron fuselage panel under shear load was completed successfully. Using NASTRAN finite-element analysis the stiffness of the panel in the linear range prior to buckling was predicted within 3.5 percent. A nonlinear analysis predicted the buckling load within 10 percent and final failure load within 6 percent. The first test of a resin transfer molding six-stringer wing panel under compression was also completed. The panel failed unexpectedly in buckling because of inadequate supporting structure. The average strain was 0.43 percent with a line load of 20.3 kips per inch of width. This strain still exceeds the design allowable strains. Also, the stringers did not debond before failure, which is in contrast to the general behavior of unstitched panels.

  15. Shear load transfer in high and low stress tendons.

    PubMed

    Kondratko-Mittnacht, Jaclyn; Duenwald-Kuehl, Sarah; Lakes, Roderic; Vanderby, Ray

    2015-05-01

    Tendon is an integral part of joint movement and stability, as it functions to transmit load from muscle to bone. It has an anisotropic, fibrous hierarchical structure that is generally loaded in the direction of its fibers/fascicles. Internal load distributions are altered when joint motion rotates an insertion site or when local damage disrupts fibers/fascicles, potentially causing inter-fiber (or inter-fascicular) shear. Tendons with different microstructures (helical versus linear) may redistribute loads differently. This study explored how shear redistributes axial loads in rat tail tendon (low stress tendons with linear microstructure) and porcine flexor tendon (high stress with helical microstructure) by creating lacerations on opposite sides of the tendon, ranging from about 20% to 60% of the tendon width, to create various magnitudes of shear. Differences in fascicular orientation were quantified using polarized light microscopy. Unexpectedly, both tendon types maintained about 20% of pre-laceration stress values after overlapping cuts of 60% of tendon width (no intact fibers end to end) suggesting that shear stress transfer can contribute more to overall tendon strength and stiffness than previously reported. All structural parameters for both tendon types decreased linearly with increasing laceration depth. The tail tendon had a more rapid decline in post-laceration elastic stress and modulus parameters as well as a more linear and less tightly packed fascicular structure, suggesting that positional tendons may be less well suited to redistribute loads via a shear mechanism. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Power generation in microbial fuel cells using platinum group metal-free cathode catalyst: Effect of the catalyst loading on performance and costs.

    PubMed

    Santoro, Carlo; Kodali, Mounika; Herrera, Sergio; Serov, Alexey; Ieropoulos, Ioannis; Atanassov, Plamen

    2018-02-28

    Platinum group metal-free (PGM-free) catalyst with different loadings was investigated in air breathing electrodes microbial fuel cells (MFCs). Firstly, the electrocatalytic activity towards oxygen reduction reaction (ORR) of the catalyst was investigated by rotating ring disk electrode (RRDE) setup with different catalyst loadings. The results showed that higher loading led to an increased in the half wave potential and the limiting current and to a further decrease in the peroxide production. The electrons transferred also slightly increased with the catalyst loading up to the value of ≈3.75. This variation probably indicates that the catalyst investigated follow a 2x2e - transfer mechanism. The catalyst was integrated within activated carbon pellet-like air-breathing cathode in eight different loadings varying between 0.1 mgcm -2 and 10 mgcm -2 . Performance were enhanced gradually with the increase in catalyst content. Power densities varied between 90 ± 9 μWcm -2 and 262 ± 4 μWcm -2 with catalyst loading of 0.1 mgcm -2 and 10 mgcm -2 respectively. Cost assessments related to the catalyst performance are presented. An increase in catalyst utilization led to an increase in power generated with a substantial increase in the whole costs. Also a decrease in performance due to cathode/catalyst deterioration over time led to a further increase in the costs.

  17. Influence of tunnel and soil parameters on vibrations from underground railways

    NASA Astrophysics Data System (ADS)

    Gupta, S.; Stanus, Y.; Lombaert, G.; Degrande, G.

    2009-10-01

    A parametric study is performed to identify the key parameters which have an important influence on the generation and propagation of vibrations from underground railways. In this paper, the parameters related to the tunnel and the soil are considered and their influence on the free field response is studied. The coupled periodic finite element-boundary element model and the pipe-in-pipe model have been used for this study. Both models account for the dynamic interaction between the train, the track, the tunnel and the soil. A general analytical formulation is used to compute the response of three-dimensional invariant or periodic media that are excited by moving loads. The response to moving loads is written in terms of the axle loads and the transfer functions. The parametric study can be carried out by separately analyzing the variations in the axle loads and the transfer functions. The axle loads are mainly influenced by the parameters related to the vehicle and the track, while the transfer functions are influenced by the properties of the track, the tunnel and the soil. In the present paper, the parameters related to the tunnel and soil are investigated. It is observed that the material damping and the shear modulus of the soil have an important influence on the propagation of vibrations. The influence of structural changes to the tunnel as well as geometrical properties such as the size and shape of the tunnel is investigated. It is observed that a larger tunnel results in a smaller response above the tunnel as more energy is radiated downwards. Moreover, it is demonstrated that the tunnel geometry has a considerable influence on the response closer to the tunnel.

  18. Thermal analysis of regenerative-cooled pylon in multi-mode rocket based combined cycle engine

    NASA Astrophysics Data System (ADS)

    Yan, Dekun; He, Guoqiang; Li, Wenqiang; Zhang, Duo; Qin, Fei

    2018-07-01

    Combining pylon injector with rocket is an effective method to achieve efficient mixing and combustion in the RBCC engine. This study designs a fuel pylon with active cooling structure, and numerically investigates the coupled heat transfer between active cooling process in the pylon and combustion in the combustor in different modes. Effect of the chemical reaction of the fuel on the flow, heat transfer and physical characteristics is also discussed. The numerical results present a good agreement with the experimental data. Results indicate that drastic supplementary combustion caused by rocket gas and secondary combustion caused by the fuel injection from the pylon result in severe thermal load on the pylon. Although regenerative cooling without cracking can reduce pylon's temperature below the allowable limit, a high-temperature area appears in the middle and nail section of the pylon due to the coolant's insufficient convective heat transfer coefficient. Comparatively, endothermic cracking can provide extra chemical heat sink for the coolant and low velocity contributes to prolong the reaction time to increase the heat absorption from chemical reaction, which further lowers and unifies the pylon surface temperature.

  19. Transfer orbit stage mechanisms thermal vacuum test

    NASA Technical Reports Server (NTRS)

    Oleary, Scott T.

    1990-01-01

    A systems level mechanisms test was conducted on the Orbital Sciences Corp.'s Transfer Orbit Stage (TOS). The TOS is a unique partially reusable transfer vehicle which will boost a satellite into its operational orbit from the Space Shuttle's cargo bay. The mechanical cradle and tilt assemblies will return to earth with the Space Shuttle while the Solid Rocket Motor (SRM) and avionics package are expended. A mechanisms test was performed on the forward cradle and aft tilting assemblies of the TOS under thermal vacuum conditions. Actuating these assemblies under a 1 g environment and thermal vacuum conditions proved to be a complex task. Pneumatic test fixturing was used to lift the forward cradle, and tilt the SRM, and avionics package. Clinometers, linear voltage displacement transducers, and load cells were used in the thermal vacuum chamber to measure the performance and characteristics of the TOS mechanism assembly. Incorporation of the instrumentation and pneumatic system into the test setup was not routine since pneumatic actuation of flight hardware had not been previously performed in the facility. The methods used are presented along with the problems experienced during the design, setup and test phases.

  20. A study of boiling heat transfer as applied to the cooling of ball bearings in the high pressure oxygen turbopump of the space shuttle main engine

    NASA Technical Reports Server (NTRS)

    Schreiber, Will

    1986-01-01

    Two sets of ball bearings support the main shaft within the High Pressure Oxygen Turbopump (HPOTP) in the Space Shuttle Main Engine (SSME). In operation, these bearings are cooled and lubricated with high pressure liquid oxygen (LOX) flowing axially through the bearing assembly. Currently, modifications in the assembly design are being contemplated in order to enhance the lifetime of the bearings and to allow the HPOTP to operate under larger loads. An understanding of the fluid dynamics and heat transfer characteristics of the flowing LOX is necessary for the implementation of these design changes. The proposed computational model of the LOX fluid dynamics, in addition to dealing with a turbulent flow in a complex geometry, must address the complication associated with boiling and two-phase flow. The feasibility of and possible methods for modeling boiling heat transfer are considered. The theory of boiling as pertains to this particular problem is reviewed. Recommendations are given for experiments which would be necessary to establish validity for correlations needed to model boiling.

  1. A Method of Data Aggregation for Wearable Sensor Systems

    PubMed Central

    Shen, Bo; Fu, Jun-Song

    2016-01-01

    Data aggregation has been considered as an effective way to decrease the data to be transferred in sensor networks. Particularly for wearable sensor systems, smaller battery has less energy, which makes energy conservation in data transmission more important. Nevertheless, wearable sensor systems usually have features like frequently dynamic changes of topologies and data over a large range, of which current aggregating methods can’t adapt to the demand. In this paper, we study the system composed of many wearable devices with sensors, such as the network of a tactical unit, and introduce an energy consumption-balanced method of data aggregation, named LDA-RT. In the proposed method, we develop a query algorithm based on the idea of ‘happened-before’ to construct a dynamic and energy-balancing routing tree. We also present a distributed data aggregating and sorting algorithm to execute top-k query and decrease the data that must be transferred among wearable devices. Combining these algorithms, LDA-RT tries to balance the energy consumptions for prolonging the lifetime of wearable sensor systems. Results of evaluation indicate that LDA-RT performs well in constructing routing trees and energy balances. It also outperforms the filter-based top-k monitoring approach in energy consumption, load balance, and the network’s lifetime, especially for highly dynamic data sources. PMID:27347953

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

    Slattery, Stuart R.

    In this study we analyze and extend mesh-free algorithms for three-dimensional data transfer problems in partitioned multiphysics simulations. We first provide a direct comparison between a mesh-based weighted residual method using the common-refinement scheme and two mesh-free algorithms leveraging compactly supported radial basis functions: one using a spline interpolation and one using a moving least square reconstruction. Through the comparison we assess both the conservation and accuracy of the data transfer obtained from each of the methods. We do so for a varying set of geometries with and without curvature and sharp features and for functions with and without smoothnessmore » and with varying gradients. Our results show that the mesh-based and mesh-free algorithms are complementary with cases where each was demonstrated to perform better than the other. We then focus on the mesh-free methods by developing a set of algorithms to parallelize them based on sparse linear algebra techniques. This includes a discussion of fast parallel radius searching in point clouds and restructuring the interpolation algorithms to leverage data structures and linear algebra services designed for large distributed computing environments. The scalability of our new algorithms is demonstrated on a leadership class computing facility using a set of basic scaling studies. Finally, these scaling studies show that for problems with reasonable load balance, our new algorithms for both spline interpolation and moving least square reconstruction demonstrate both strong and weak scalability using more than 100,000 MPI processes with billions of degrees of freedom in the data transfer operation.« less

  3. Proceedings of the Annual Academic Apparel Research Conference on Advanced Apparel Manufacturing Technology Demonstration (1st) Held in Philadelphia, Pennsylvania on 14-16 February 1990. Volume 2

    DTIC Science & Technology

    1990-02-16

    Philadelphia, PA by Dr. Leo E. Hanifin, Director Center for Manufacturing Productivity and Technology Transfer and Co-Principal Investigator Background In...Is coordinated by Dr. Leo E. Hanifin and Involves an additional four graduate students, two programmers, one engineer and one technician. In addition...the transfer bit5 - Whether the transfer is a load or unload * 4 bit4 - Which side of the AGV to perform the transfer bit3 through bitO - The number of

  4. Nutrient loads within the Sava River Catchment and comparison with load relations in the Baltic region

    NASA Astrophysics Data System (ADS)

    Levi, Lea; Cvetkovic, Vladimir; Destouni, Georgia

    2015-04-01

    This study compiles estimates of total nitrogen and phosphorus loads in the Sava River Catchment (SRC), investigates the load relations to human drivers of excess nutrient loading, and compares them with corresponding relations implied by data reported for the Baltic region. Nutrient load data, associated average discharge concentrations (ratio of load to water discharge) and their relations to human drivers are investigated across subcatchments of the SRC with different agricultural and population conditions. The Zagreb subcatchment, which has the smallest area but the highest population density and runoff among the investigated SRC subcatchments, exhibits the highest loads of both nitrogen and phosphorus. Overall for the SRC, results show high correlation (R2=0.93-0.95) of nutrient loads with population density and of concentrations with farmland share. A further question investigated here is then to what degree these relations are comparable with such relations found also for the Baltic region. The two regions are otherwise quite different in their climatic, agricultural and wastewater treatment conditions, so relation consistency, even if surprising, would be important in indicating some degree of relation transferability worthy of further investigation also in other regions. For the Baltic region corresponding correlations to those found in the SRC are in the range R2=0.79-0.88. In particular nitrogen and phosphorus concentration correlations with farmland share are qualitatively consistent between the regions. At the same time, phosphorus concentration correlation with population density shows quite different results between regions. Obtained results indicate a certain level of transferability of dependencies between the two regions and call for further detailed investigations on finer spatial-temporal scales.

  5. A Novel System for Simultaneous or Sequential Integration of Multiple Gene-Loading Vectors into a Defined Site of a Human Artificial Chromosome

    PubMed Central

    Suzuki, Teruhiko; Kazuki, Yasuhiro; Oshimura, Mitsuo; Hara, Takahiko

    2014-01-01

    Human artificial chromosomes (HACs) are gene-delivery vectors suitable for introducing large DNA fragments into mammalian cells. Although a HAC theoretically incorporates multiple gene expression cassettes of unlimited DNA size, its application has been limited because the conventional gene-loading system accepts only one gene-loading vector (GLV) into a HAC. We report a novel method for the simultaneous or sequential integration of multiple GLVs into a HAC vector (designated as the SIM system) via combined usage of Cre, FLP, Bxb1, and φC31 recombinase/integrase. As a proof of principle, we first attempted simultaneous integration of three GLVs encoding EGFP, Venus, and TdTomato into a gene-loading site of a HAC in CHO cells. These cells successfully expressed all three fluorescent proteins. Furthermore, microcell-mediated transfer of HACs enabled the expression of those fluorescent proteins in recipient cells. We next demonstrated that GLVs could be introduced into a HAC one-by-one via reciprocal usage of recombinase/integrase. Lastly, we introduced a fourth GLV into a HAC after simultaneous integration of three GLVs by FLP-mediated DNA recombination. The SIM system expands the applicability of HAC vectors and is useful for various biomedical studies, including cell reprogramming. PMID:25303219

  6. A novel system for simultaneous or sequential integration of multiple gene-loading vectors into a defined site of a human artificial chromosome.

    PubMed

    Suzuki, Teruhiko; Kazuki, Yasuhiro; Oshimura, Mitsuo; Hara, Takahiko

    2014-01-01

    Human artificial chromosomes (HACs) are gene-delivery vectors suitable for introducing large DNA fragments into mammalian cells. Although a HAC theoretically incorporates multiple gene expression cassettes of unlimited DNA size, its application has been limited because the conventional gene-loading system accepts only one gene-loading vector (GLV) into a HAC. We report a novel method for the simultaneous or sequential integration of multiple GLVs into a HAC vector (designated as the SIM system) via combined usage of Cre, FLP, Bxb1, and φC31 recombinase/integrase. As a proof of principle, we first attempted simultaneous integration of three GLVs encoding EGFP, Venus, and TdTomato into a gene-loading site of a HAC in CHO cells. These cells successfully expressed all three fluorescent proteins. Furthermore, microcell-mediated transfer of HACs enabled the expression of those fluorescent proteins in recipient cells. We next demonstrated that GLVs could be introduced into a HAC one-by-one via reciprocal usage of recombinase/integrase. Lastly, we introduced a fourth GLV into a HAC after simultaneous integration of three GLVs by FLP-mediated DNA recombination. The SIM system expands the applicability of HAC vectors and is useful for various biomedical studies, including cell reprogramming.

  7. Temperature variations at nano-scale level in phase transformed nanocrystalline NiTi shape memory alloys adjacent to graphene layers.

    PubMed

    Amini, Abbas; Cheng, Chun; Naebe, Minoo; Church, Jeffrey S; Hameed, Nishar; Asgari, Alireza; Will, Frank

    2013-07-21

    The detection and control of the temperature variation at the nano-scale level of thermo-mechanical materials during a compression process have been challenging issues. In this paper, an empirical method is proposed to predict the temperature at the nano-scale level during the solid-state phase transition phenomenon in NiTi shape memory alloys. Isothermal data was used as a reference to determine the temperature change at different loading rates. The temperature of the phase transformed zone underneath the tip increased by ∼3 to 40 °C as the loading rate increased. The temperature approached a constant with further increase in indentation depth. A few layers of graphene were used to enhance the cooling process at different loading rates. Due to the presence of graphene layers the temperature beneath the tip decreased by a further ∼3 to 10 °C depending on the loading rate. Compared with highly polished NiTi, deeper indentation depths were also observed during the solid-state phase transition, especially at the rate dependent zones. Larger superelastic deformations confirmed that the latent heat transfer through the deposited graphene layers allowed a larger phase transition volume and, therefore, more stress relaxation and penetration depth.

  8. Background Document for an Advanced Personal Load Carriage System for the Canadian Forces

    DTIC Science & Technology

    1995-03-29

    after field operations can be an invaluable source of knowledge regarding evaluations of equipment and physical fitness of soldiers, as well as...overloaded. It follows, therefore, that the value of knowledge regarding load carriage is limitless, whether it be knowledge of the load weight carried or...some transfer of weight to the hips. Typically internal frame packs are used by active outdoors people suCh as climbers and skiers . · Pack

  9. Multicoil resonance-based parallel array for smart wireless power delivery.

    PubMed

    Mirbozorgi, S A; Sawan, M; Gosselin, B

    2013-01-01

    This paper presents a novel resonance-based multicoil structure as a smart power surface to wirelessly power up apparatus like mobile, animal headstage, implanted devices, etc. The proposed powering system is based on a 4-coil resonance-based inductive link, the resonance coil of which is formed by an array of several paralleled coils as a smart power transmitter. The power transmitter employs simple circuit connections and includes only one power driver circuit per multicoil resonance-based array, which enables higher power transfer efficiency and power delivery to the load. The power transmitted by the driver circuit is proportional to the load seen by the individual coil in the array. Thus, the transmitted power scales with respect to the load of the electric/electronic system to power up, and does not divide equally over every parallel coils that form the array. Instead, only the loaded coils of the parallel array transmit significant part of total transmitted power to the receiver. Such adaptive behavior enables superior power, size and cost efficiency then other solutions since it does not need to use complex detection circuitry to find the location of the load. The performance of the proposed structure is verified by measurement results. Natural load detection and covering 4 times bigger area than conventional topologies with a power transfer efficiency of 55% are the novelties of presented paper.

  10. Relative significance of heat transfer processes to quantify tradeoffs between complexity and accuracy of energy simulations with a building energy use patterns classification

    NASA Astrophysics Data System (ADS)

    Heidarinejad, Mohammad

    This dissertation develops rapid and accurate building energy simulations based on a building classification that identifies and focuses modeling efforts on most significant heat transfer processes. The building classification identifies energy use patterns and their contributing parameters for a portfolio of buildings. The dissertation hypothesis is "Building classification can provide minimal required inputs for rapid and accurate energy simulations for a large number of buildings". The critical literature review indicated there is lack of studies to (1) Consider synoptic point of view rather than the case study approach, (2) Analyze influence of different granularities of energy use, (3) Identify key variables based on the heat transfer processes, and (4) Automate the procedure to quantify model complexity with accuracy. Therefore, three dissertation objectives are designed to test out the dissertation hypothesis: (1) Develop different classes of buildings based on their energy use patterns, (2) Develop different building energy simulation approaches for the identified classes of buildings to quantify tradeoffs between model accuracy and complexity, (3) Demonstrate building simulation approaches for case studies. Penn State's and Harvard's campus buildings as well as high performance LEED NC office buildings are test beds for this study to develop different classes of buildings. The campus buildings include detailed chilled water, electricity, and steam data, enabling to classify buildings into externally-load, internally-load, or mixed-load dominated. The energy use of the internally-load buildings is primarily a function of the internal loads and their schedules. Externally-load dominated buildings tend to have an energy use pattern that is a function of building construction materials and outdoor weather conditions. However, most of the commercial medium-sized office buildings have a mixed-load pattern, meaning the HVAC system and operation schedule dictate the indoor condition regardless of the contribution of internal and external loads. To deploy the methodology to another portfolio of buildings, simulated LEED NC office buildings are selected. The advantage of this approach is to isolate energy performance due to inherent building characteristics and location, rather than operational and maintenance factors that can contribute to significant variation in building energy use. A framework for detailed building energy databases with annual energy end-uses is developed to select variables and omit outliers. The results show that the high performance office buildings are internally-load dominated with existence of three different clusters of low-intensity, medium-intensity, and high-intensity energy use pattern for the reviewed office buildings. Low-intensity cluster buildings benefit from small building area, while the medium- and high-intensity clusters have a similar range of floor areas and different energy use intensities. Half of the energy use in the low-intensity buildings is associated with the internal loads, such as lighting and plug loads, indicating that there are opportunities to save energy by using lighting or plug load management systems. A comparison between the frameworks developed for the campus buildings and LEED NC office buildings indicates these two frameworks are complementary to each other. Availability of the information has yielded to two different procedures, suggesting future studies for a portfolio of buildings such as city benchmarking and disclosure ordinance should collect and disclose minimal required inputs suggested by this study with the minimum level of monthly energy consumption granularity. This dissertation developed automated methods using the OpenStudio API (Application Programing Interface) to create energy models based on the building class. ASHRAE Guideline 14 defines well-accepted criteria to measure accuracy of energy simulations; however, there is no well-accepted methodology to quantify the model complexity without the influence of the energy modeler judgment about the model complexity. This study developed a novel method using two weighting factors, including weighting factors based on (1) computational time and (2) easiness of on-site data collection, to measure complexity of the energy models. Therefore, this dissertation enables measurement of both model complexity and accuracy as well as assessment of the inherent tradeoffs between energy simulation model complexity and accuracy. The results of this methodology suggest for most of the internal load contributors such as operation schedules the on-site data collection adds more complexity to the model compared to the computational time. Overall, this study provided specific data on tradeoffs between accuracy and model complexity that points to critical inputs for different building classes, rather than an increase in the volume and detail of model inputs as the current research and consulting practice indicates. (Abstract shortened by UMI.).

  11. WASTE HANDLING BUILDING ELECTRICAL SYSTEM DESCRIPTION DOCUMENT

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

    S.C. Khamamkar

    2000-06-23

    The Waste Handling Building Electrical System performs the function of receiving, distributing, transforming, monitoring, and controlling AC and DC power to all waste handling building electrical loads. The system distributes normal electrical power to support all loads that are within the Waste Handling Building (WHB). The system also generates and distributes emergency power to support designated emergency loads within the WHB within specified time limits. The system provides the capability to transfer between normal and emergency power. The system provides emergency power via independent and physically separated distribution feeds from the normal supply. The designated emergency electrical equipment will bemore » designed to operate during and after design basis events (DBEs). The system also provides lighting, grounding, and lightning protection for the Waste Handling Building. The system is located in the Waste Handling Building System. The system consists of a diesel generator, power distribution cables, transformers, switch gear, motor controllers, power panel boards, lighting panel boards, lighting equipment, lightning protection equipment, control cabling, and grounding system. Emergency power is generated with a diesel generator located in a QL-2 structure and connected to the QL-2 bus. The Waste Handling Building Electrical System distributes and controls primary power to acceptable industry standards, and with a dependability compatible with waste handling building reliability objectives for non-safety electrical loads. It also generates and distributes emergency power to the designated emergency loads. The Waste Handling Building Electrical System receives power from the Site Electrical Power System. The primary material handling power interfaces include the Carrier/Cask Handling System, Canister Transfer System, Assembly Transfer System, Waste Package Remediation System, and Disposal Container Handling Systems. The system interfaces with the MGR Operations Monitoring and Control System for supervisory monitoring and control signals. The system interfaces with all facility support loads such as heating, ventilation, and air conditioning, office, fire protection, monitoring and control, safeguards and security, and communications subsystems.« less

  12. Field investigation of low-temperature cracking and stiffness moduli on selected roads with conventional and high modulus asphalt concrete

    NASA Astrophysics Data System (ADS)

    Judycki, Józef; Jaczewski, Mariusz; Ryś, Dawid; Pszczoła, Marek; Jaskuła, Piotr; Glinicki, Adam

    2017-09-01

    High Modulus Asphalt Concrete (HMAC) was introduced in Poland as a one of the solutions to the problem of rutting, type of deterioration common in the 1990s. After first encouraging trials in 2002 HMAC was widely used for heavily loaded national roads and motorways. However some concerns were raised about low-temperature cracking of HMAC. This was the main reason of the studies presented in this article were started. The article presents the comparison of performance of pavements constructed in typical contract conditions with the road bases made of HMAC and conventional asphalt concrete (AC). The field investigation was focused on the number of low-temperature cracks, bearing capacity (based on FWD test) of road sections localized in coldest region of Poland. Also load transfer efficiency of selected low-temperature cracks was assessed. FWD test confirmed lower deflections of pavements with HMAC and two times higher stiffness modulus of asphalt courses in comparison to pavements constructed with conventional AC mixtures. Relation of stiffness of asphalt layers and amount of low-temperature cracks showed that the higher stiffness modulus of asphalt layers could lead to increase of the number of low-temperature cracks. FWD test results showed that the load transfer efficiency of low-temperature cracks on pavements with HMAC presents very low values, very close to lack of load transfer. It was surprising as section with HMAC road base were aged from 2 to 5 years and presented very good bearing capacity.

  13. Multifunctional nanocomposite hollow fiber membranes by solvent transfer induced phase separation.

    PubMed

    Haase, Martin F; Jeon, Harim; Hough, Noah; Kim, Jong Hak; Stebe, Kathleen J; Lee, Daeyeon

    2017-11-01

    The decoration of porous membranes with a dense layer of nanoparticles imparts useful functionality and can enhance membrane separation and anti-fouling properties. However, manufacturing of nanoparticle-coated membranes requires multiple steps and tedious processing. Here, we introduce a facile single-step method in which bicontinuous interfacially jammed emulsions are used to form nanoparticle-functionalized hollow fiber membranes. The resulting nanocomposite membranes prepared via solvent transfer-induced phase separation and photopolymerization have exceptionally high nanoparticle loadings (up to 50 wt% silica nanoparticles) and feature densely packed nanoparticles uniformly distributed over the entire membrane surfaces. These structurally well-defined, asymmetric membranes facilitate control over membrane flux and selectivity, enable the formation of stimuli responsive hydrogel nanocomposite membranes, and can be easily modified to introduce antifouling features. This approach forms a foundation for the formation of advanced nanocomposite membranes comprising diverse building blocks with potential applications in water treatment, industrial separations and as catalytic membrane reactors.

  14. Optimization of output power and transmission efficiency of magnetically coupled resonance wireless power transfer system

    NASA Astrophysics Data System (ADS)

    Yan, Rongge; Guo, Xiaoting; Cao, Shaoqing; Zhang, Changgeng

    2018-05-01

    Magnetically coupled resonance (MCR) wireless power transfer (WPT) system is a promising technology in electric energy transmission. But, if its system parameters are designed unreasonably, output power and transmission efficiency will be low. Therefore, optimized parameters design of MCR WPT has important research value. In the MCR WPT system with designated coil structure, the main parameters affecting output power and transmission efficiency are the distance between the coils, the resonance frequency and the resistance of the load. Based on the established mathematical model and the differential evolution algorithm, the change of output power and transmission efficiency with parameters can be simulated. From the simulation results, it can be seen that output power and transmission efficiency of the two-coil MCR WPT system and four-coil one with designated coil structure are improved. The simulation results confirm the validity of the optimization method for MCR WPT system with designated coil structure.

  15. 49 CFR 173.319 - Cryogenic liquids in tank cars.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... increase more than 25 microns during the 24-hour period; or (ii) Calculated heat transfer rate test. The insulation system must be performance tested as prescribed in § 179.400-4 of this subchapter. When the calculated heat transfer rate test is performed, the absolute pressure in the annular space of the loaded...

  16. 49 CFR 173.319 - Cryogenic liquids in tank cars.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... increase more than 25 microns during the 24-hour period; or (ii) Calculated heat transfer rate test. The insulation system must be performance tested as prescribed in § 179.400-4 of this subchapter. When the calculated heat transfer rate test is performed, the absolute pressure in the annular space of the loaded...

  17. 49 CFR 173.319 - Cryogenic liquids in tank cars.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... increase more than 25 microns during the 24-hour period; or (ii) Calculated heat transfer rate test. The insulation system must be performance tested as prescribed in § 179.400-4 of this subchapter. When the calculated heat transfer rate test is performed, the absolute pressure in the annular space of the loaded...

  18. 49 CFR 173.319 - Cryogenic liquids in tank cars.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... increase more than 25 microns during the 24-hour period; or (ii) Calculated heat transfer rate test. The insulation system must be performance tested as prescribed in § 179.400-4 of this subchapter. When the calculated heat transfer rate test is performed, the absolute pressure in the annular space of the loaded...

  19. 49 CFR 173.319 - Cryogenic liquids in tank cars.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... increase more than 25 microns during the 24-hour period; or (ii) Calculated heat transfer rate test. The insulation system must be performance tested as prescribed in § 179.400-4 of this subchapter. When the calculated heat transfer rate test is performed, the absolute pressure in the annular space of the loaded...

  20. 14 CFR 133.27 - Availability, transfer, and surrender of certificate.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... certificate. 133.27 Section 133.27 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... ROTORCRAFT EXTERNAL-LOAD OPERATIONS Certification Rules § 133.27 Availability, transfer, and surrender of..., 1964, as amended by Amdt. 133-9, 51 FR 40708, Nov. 7, 1986; Amdt. 133-11, 54 FR 39294, Sept. 25, 1989] ...

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