WorldWideScience

Sample records for force base ca

  1. Weather Research and Forecasting Model Wind Sensitivity Study at Edwards Air Force Base, CA

    Science.gov (United States)

    Watson, Leela R.; Bauman, William H., III; Hoeth, Brian

    2009-01-01

    This abstract describes work that will be done by the Applied Meteorology Unit (AMU) in assessing the success of different model configurations in predicting "wind cycling" cases at Edwards Air Force Base, CA (EAFB), in which the wind speeds and directions oscillate among towers near the EAFB runway. The Weather Research and Forecasting (WRF) model allows users to choose among two dynamical cores - the Advanced Research WRF (ARW) and the Non-hydrostatic Mesoscale Model (NMM). There are also data assimilation analysis packages available for the initialization of the WRF model - the Local Analysis and Prediction System (LAPS) and the Advanced Regional Prediction System (ARPS) Data Analysis System (ADAS). Having a series of initialization options and WRF cores, as well as many options within each core, creates challenges for local forecasters, such as determining which configuration options are best to address specific forecast concerns. The goal of this project is to assess the different configurations available and determine which configuration will best predict surface wind speed and direction at EAFB.

  2. Statistical Short-Range Guidance for Peak Wind Speed Forecasts at Edwards Air Force Base, CA

    Science.gov (United States)

    Dreher, Joseph G.; Crawford, Winifred; Lafosse, Richard; Hoeth, Brian; Burns, Kerry

    2009-01-01

    The peak winds near the surface are an important forecast element for space shuttle landings. As defined in the Flight Rules (FR), there are peak wind thresholds that cannot be exceeded in order to ensure the safety of the shuttle during landing operations. The National Weather Service Spaceflight Meteorology Group (SMG) is responsible for weather forecasts for all shuttle landings, and is required to issue surface average and 10-minute peak wind speed forecasts. They indicate peak winds are a challenging parameter to forecast. To alleviate the difficulty in making such wind forecasts, the Applied Meteorology Unit (AMU) developed a PC-based graphical user interface (GUI) for displaying peak wind climatology and probabilities of exceeding peak wind thresholds for the Shuttle Landing Facility (SLF) at Kennedy Space Center (KSC; Lambert 2003). However, the shuttle occasionally may land at Edwards Air Force Base (EAFB) in southern California when weather conditions at KSC in Florida are not acceptable, so SMG forecasters requested a similar tool be developed for EAFB.

  3. Weather Research and Forecasting Model Wind Sensitivity Study at Edwards Air Force Base, CA

    Science.gov (United States)

    Watson, Leela R.; Bauman, William H., III

    2008-01-01

    NASA prefers to land the space shuttle at Kennedy Space Center (KSC). When weather conditions violate Flight Rules at KSC, NASA will usually divert the shuttle landing to Edwards Air Force Base (EAFB) in Southern California. But forecasting surface winds at EAFB is a challenge for the Spaceflight Meteorology Group (SMG) forecasters due to the complex terrain that surrounds EAFB, One particular phenomena identified by SMG is that makes it difficult to forecast the EAFB surface winds is called "wind cycling". This occurs when wind speeds and directions oscillate among towers near the EAFB runway leading to a challenging deorbit bum forecast for shuttle landings. The large-scale numerical weather prediction models cannot properly resolve the wind field due to their coarse horizontal resolutions, so a properly tuned high-resolution mesoscale model is needed. The Weather Research and Forecasting (WRF) model meets this requirement. The AMU assessed the different WRF model options to determine which configuration best predicted surface wind speed and direction at EAFB, To do so, the AMU compared the WRF model performance using two hot start initializations with the Advanced Research WRF and Non-hydrostatic Mesoscale Model dynamical cores and compared model performance while varying the physics options.

  4. Statistical Short-Range Guidance for Peak Wind Speed Forecasts at Edwards Air Force Base, CA

    Science.gov (United States)

    Dreher, Joseph; Crawford, Winifred; Lafosse, Richard; Hoeth, Brian; Burns, Kerry

    2008-01-01

    The peak winds near the surface are an important forecast element for Space Shuttle landings. As defined in the Shuttle Flight Rules (FRs), there are peak wind thresholds that cannot be exceeded in order to ensure the safety of the shuttle during landing operations. The National Weather Service Spaceflight Meteorology Group (SMG) is responsible for weather forecasts for all shuttle landings. They indicate peak winds are a challenging parameter to forecast. To alleviate the difficulty in making such wind forecasts, the Applied Meteorology Unit (AMTJ) developed a personal computer based graphical user interface (GUI) for displaying peak wind climatology and probabilities of exceeding peak-wind thresholds for the Shuttle Landing Facility (SLF) at Kennedy Space Center. However, the shuttle must land at Edwards Air Force Base (EAFB) in southern California when weather conditions at Kennedy Space Center in Florida are not acceptable, so SMG forecasters requested that a similar tool be developed for EAFB. Marshall Space Flight Center (MSFC) personnel archived and performed quality control of 2-minute average and 10-minute peak wind speeds at each tower adjacent to the main runway at EAFB from 1997- 2004. They calculated wind climatologies and probabilities of average peak wind occurrence based on the average speed. The climatologies were calculated for each tower and month, and were stratified by hour, direction, and direction/hour. For the probabilities of peak wind occurrence, MSFC calculated empirical and modeled probabilities of meeting or exceeding specific 10-minute peak wind speeds using probability density functions. The AMU obtained and reformatted the data into Microsoft Excel PivotTables, which allows users to display different values with point-click-drag techniques. The GUT was then created from the PivotTables using Visual Basic for Applications code. The GUI is run through a macro within Microsoft Excel and allows forecasters to quickly display and

  5. Hanscom Air Force Base

    Data.gov (United States)

    Federal Laboratory Consortium — MIT Lincoln Laboratory occupies 75 acres (20 acres of which are MIT property) on the eastern perimeter of Hanscom Air Force Base, which is at the nexus of Lexington,...

  6. Space Shuttle Atlantis landing at 12:33 p.m. February 20 on the runway at Edwards Air Force Base, Ca

    Science.gov (United States)

    2001-01-01

    Space Shuttle Atlantis landed at 12:33 p.m. February 20 on the runway at Edwards Air Force Base, California, where NASA's Dryden Flight Research Center is located. The mission, which began February 7, logged 5.3 million miles as the shuttle orbited earth while delivering the Destiny science laboratory to the International Space Station. Inclement weather conditions in Florida prompted the decision to land Atlantis at Edwards. The last time a space shuttle landed at Edwards was Oct. 24, 2000.

  7. Superfund record of decision (EPA Region 9): McClellan Air Force Base, Basewide Groundwater Operable Unit, Sacramento, CA, May 11, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The Interim Record of Decision (ROD) presents the interim remedial action for the Groundwater Operable Unit (Groundwater OU) at the McClellan Air Force Base (McClellan AFB) Superfund site in Sacramento, California. The Groundwater OU addresses all of the VOC-contaminated groundwater at McClellan AFB. The Groundwater OU remedy is designed to prevent the spread of contamination that is already in the groundwater by containing groundwater with concentrations greater than maximum contaminant levels (MCLs). The remedy is also designed to remove to the maximum extent practicable the mass of contamination that lies in that volume of the groundwater.

  8. US Air Force Base Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hourly observations taken by U.S. Air Force personnel at bases in the United States and around the world. Foreign observations concentrated in the Middle East and...

  9. Maximal Force Characteristics of the Ca2+-Powered Actuator of Vorticella convallaria

    OpenAIRE

    Ryu, Sangjin; Lang, Matthew J.; Matsudaira, Paul

    2012-01-01

    The millisecond stalk contraction of the sessile ciliate Vorticella convallaria is powered by energy from Ca2+ binding to generate contractile forces of ∼10 nN. Its contractile organelle, the spasmoneme, generates higher contractile force under increased stall resistances. By applying viscous drag force to contracting V. convallaria in a microfluidic channel, we observed that the mechanical force and work of the spasmoneme depended on the stalk length, i.e., the maximum tension (150–350 nN) a...

  10. Can three-neutron forces be constrained by empirical information on the neutron skin of 48Ca and 208Pb?

    CERN Document Server

    Sammarruca, Francesca

    2016-01-01

    We calculate the neutron matter equation of state from two-neutron forces up to ?fifth order of the chiral expansion and investigate the order-by-order convergence of the predictions. Based on these equations of state, we derive the binding energies and the neutron and proton density distributions in 208Pb and 48Ca, with particular attention to the neutron skins. Anticipating future experiments which will provide reliable information on the weak charge density in nuclei, we discuss the theoretical uncertainties and the possibility of constraining the size of three-neutron forces in neutron matter.

  11. Maximal force characteristics of the Ca(2+)-powered actuator of Vorticella convallaria.

    Science.gov (United States)

    Ryu, Sangjin; Lang, Matthew J; Matsudaira, Paul

    2012-09-05

    The millisecond stalk contraction of the sessile ciliate Vorticella convallaria is powered by energy from Ca(2+) binding to generate contractile forces of ∼10 nN. Its contractile organelle, the spasmoneme, generates higher contractile force under increased stall resistances. By applying viscous drag force to contracting V. convallaria in a microfluidic channel, we observed that the mechanical force and work of the spasmoneme depended on the stalk length, i.e., the maximum tension (150-350 nN) and work linearly depended on the stalk length (∼2.5 nN and ∼30 fJ per 1 μm of the stalk). This stalk-length dependency suggests that motor units of the spasmoneme may be organized in such a way that the mechanical force and work of each unit cumulate in series along the spasmoneme.

  12. Distinct mechanisms regulating mechanical force-induced Ca2+ signals at the plasma membrane and the ER in human MSCs

    NARCIS (Netherlands)

    Kim, T.J.; Joo, C.; Seong, J.; Vafabakhsh, R.; Botvinick, E.L.; Berns, M.W.; Palmer, A.E.; Wang, N.; Ha, T.; Jakobsson, E.; Sun, J.; Wang, Y.

    2015-01-01

    It is unclear that how subcellular organelles respond to external mechanical stimuli. Here, we investigated the molecular mechanisms by which mechanical force regulates Ca2+ signaling at endoplasmic reticulum (ER) in human mesenchymal stem cells. Without extracellular Ca2+, ER Ca2+ release is the so

  13. Distinct mechanisms regulating mechanical force-induced Ca2+ signals at the plasma membrane and the ER in human MSCs

    NARCIS (Netherlands)

    Kim, T.J.; Joo, C.; Seong, J.; Vafabakhsh, R.; Botvinick, E.L.; Berns, M.W.; Palmer, A.E.; Wang, N.; Ha, T.; Jakobsson, E.; Sun, J.; Wang, Y.

    2015-01-01

    It is unclear that how subcellular organelles respond to external mechanical stimuli. Here, we investigated the molecular mechanisms by which mechanical force regulates Ca2+ signaling at endoplasmic reticulum (ER) in human mesenchymal stem cells. Without extracellular Ca2+, ER Ca2+ release is the

  14. The investigation on sulfation of modified Ca-based sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Hongwei Chen; Chunbo Wang; Yonghua Li; Zijie Wang [North China Electric Power University, Baoding (China). Department of Power Engineering

    2003-07-01

    The sulfation of a limestone modified by Na{sub 2}CO{sub 3} was investigated in this paper, which aimed to find the causes of its enhanced sulfation capacity. It was shown in the experiment that although the sulfur capture capability of M-CaO (the CaO calcined from modified limestone) is in excess of that of N-CaO (the CaO calcined from original sample), the specific surface area and porosity of the former are much less than that of the latter and also the average pore radius of the former become bigger. Based on the solid-state ion diffusion theory, a new mechanism to explain M-CaO sulfation is suggested. More lattice defects are formed in M-CaO, which reduce the resistance of ion diffusion in the CaSO{sub 4} product layer, and increase the Ca-conversion. To verify this, XRD was applied to measure the crystal structures of CaO samples. It was found M-CaO has bigger lattice distortion than N-CaO. It means that M-CaO has more lattice defects. In the sulfation the lattice defects in M-CaO will go into the CaSO{sub 4} product layer and it is that accelerates the ion diffusivity and leads to the higher Ca-conversion than that of N-CaO. By scanning the element distribution in reacted M-CaO using SEM, how the lattice defects formed in the product layers was verified.

  15. Installation Restoration Program. Phase I. Records Search, Peterson Air Force Base, Colorado.

    Science.gov (United States)

    1985-08-05

    GUNN so" a. 105VI A [ads SALIDA to(, A- I Ponce, Tous 50 2 Haswell Creek AP ’all or & Ca , Lm enross Arlington Sargent, 1 10Park IF renc Sugar 6...headquartered at Ent Air Force Base near downtown Colorado Springs, thus reopening the base. When the 15th Air Force moved to California in December 1949

  16. Deployed Flight Test of the Iraqi Air Force Comp Air 7SLX (CA-7)

    Science.gov (United States)

    2014-02-28

    airframe, performance, flying qualities, and avionics . The program was highly visible, drawing the interest of the commander of AFMC, 3 General Bruce...Air Force Historical Research Agency, Maxwell Air Force Base, Ala . (hereafter AFHRA). 2 Brfg (U), “Coordination/Approval Briefing for the Limited

  17. Final Supplemental Environmental Impact Statement for Airborne Laser Program at Kirtland Air Force Base (AFB) and White Sands Missile Range/Holloman AFB, NM, and Edwards AFB and Vandenberg AFB, CA

    Science.gov (United States)

    2003-06-01

    Anadarko, OK 73005 Bosque Del Apache Wildlife Refuge P.O. Box 1246 Socorro, NM 87801 Jornada Experimental Refuge New Mexico State University...Lornpoc, CA 93436.3406 New Mexico State Library 1209 Camino Carlos Rey Santa Fe, NM 87507-5166 New Mexico Tech Library 801 Leroy Place Socorro

  18. Doublet stimulation increases Ca(2+) binding to troponin C to ensure rapid force development in skeletal muscle.

    Science.gov (United States)

    Bakker, Anthony J; Cully, Tanya R; Wingate, Catherine D; Barclay, Christopher J; Launikonis, Bradley S

    2017-03-06

    Fast-twitch skeletal muscle fibers are often exposed to motor neuron double discharges (≥200 Hz), which markedly increase both the rate of contraction and the magnitude of the resulting force responses. However, the mechanism responsible for these effects is poorly understood, likely because of technical limitations in previous studies. In this study, we measured cytosolic Ca(2+) during doublet activation using the low-affinity indicator Mag-Fluo-4 at high temporal resolution and modeled the effects of doublet stimulation on sarcoplasmic reticulum (SR) Ca(2+) release, binding of Ca(2+) to cytosolic buffers, and force enhancement in fast-twitch fibers. Single isolated fibers respond to doublet pulses with two clear Ca(2+) spikes, at doublet frequencies up to 1 KHz. A 200-Hz doublet at the start of a tetanic stimulation train (70 Hz) decreases the drop in free Ca(2+) between the first three Ca(2+) spikes of the transient, maintaining a higher overall free Ca(2+) level during first 20-30 ms of the response. Doublet stimulation also increased the rate of force development in isolated fast-twitch muscles. We also modeled SR Ca(2+) release rates during doublet stimulation and showed that Ca(2+)-dependent inactivation of ryanodine receptor activity is rapid, occurring ≤1ms after initial release. Furthermore, we modeled Ca(2+) binding to the main intracellular Ca(2+) buffers of troponin C (TnC), parvalbumin, and the SR Ca(2+) pump during Ca(2+) release and found that the main effect of the second response in the doublet is to more rapidly increase the occupation of the second Ca(2+)-binding site on TnC (TnC2), resulting in earlier activation of force. We conclude that doublet stimulation maintains high cytosolic Ca(2+) levels for longer in the early phase of the Ca(2+) response, resulting in faster saturation of TnC2 with Ca(2+), faster initiation of cross-bridge cycling, and more rapid force development.

  19. Relationship between depolarization-induced force responses and Ca2+ content in skeletal muscle fibres of rat and toad.

    Science.gov (United States)

    Owen, V J; Lamb, G D; Stephenson, D G; Fryer, M W

    1997-02-01

    1. The relationship between the total Ca2+ content of a muscle fibre and the magnitude of the force response to depolarization was examined in mechanically skinned fibres from the iliofibularis muscle of the toad and the extensor digitorum longus muscle of the rat. The response to depolarization in each skinned fibre was assessed either at the endogenous level of Ca2+ content or after depleting the fibre of Ca2+ to some degree. Ca2+ content was determined by a fibre lysing technique. 2. In both muscle types, the total Ca2+ content could be reduced from the endogenous level of approximately 1.3 mmol l-1 (expressed relative to intact fibre volume) to approximately 0.25 mmol l-1 by either depolarization or caffeine application in the presence of Ca2+ chelators, showing that the great majority of the Ca2+ was stored in the sarcoplasmic reticulum (SR). Chelation of Ca2+ in the transverse tubular (T-) system, either by exposure of fibres to EGTA before skinning or by permeabilizing the T-system with saponin after skinning, reduced the lower limit of Ca2+ content to < or = 0.12 mmol l-1, indicating that 10-20% of the total fibre Ca2+ resided in the T-system. 3. In toad fibres, both the peak and the area (i.e. time integral) of the force response to depolarization were reduced by any reduction in SR Ca2+ content, with both decreasing to zero in an approximately linear manner as the SR Ca2+ content was reduced to < 15% of the endogenous level. In rat fibres, the peak size of the force response was less affected by small decreases in SR content, but both the peak and area of the response decreased to zero with greater depletion. In partially depleted toad fibres, inhibition of SR Ca2+ uptake potentiated the force response to depolarization almost 2-fold. 4. The results show that in this skinned fibre preparation: (a) T-system depolarization and caffeine application can each virtually fully deplete the SR of Ca2+, irrespective of any putative inhibitory effect of SR depletion

  20. Vision-based measurement of microassembly forces

    Science.gov (United States)

    Anis, Y. H.; Mills, J. K.; Cleghorn, W. L.

    2006-08-01

    This work describes a vision-based force sensing method for measuring microforces acting upon the jaws of passive, compliant microgrippers, used to construct 3D microstructures. The importance of jaw force measurement during microassembly is to confirm that the microgripper-micropart makes a successful grasp and to protect the microparts and microgripper from excessive forces which may lead to damage during the assembly process. Finite-element analysis of the microgripper is performed to determine the relation between the displacement and the resultant forces of its jaw. The resulting nearly linear force-displacement relationship is fitted to a first-degree equation. A mathematical model of the microgripper system validated this force-displacement relation. The proposed vision-based gripper force measurement techniques determine the deflections of the microgripper jaws during the microassembly process. The deflections in the gripper jaws are measured during the microassembly processes through computation of the relative displacements of the right and left microgripper jaws with respect to the microgripper base. Two approaches are proposed. The first approach uses pattern identification to measure these relative displacements. Two-dimensional pattern identification is performed using normalized cross-correlation to estimate the degree to which the image and pattern are correlated. The second approach uses object recognition and image processing methods, such as zero-crossing Laplacian of Gaussian edge detection and region filling. Experiments performed confirm the success of both approaches in measuring the microgripper jaw deflections and therefore the assembly forces.

  1. Velocity, force, power, and Ca2+ sensitivity of fast and slow monkey skeletal muscle fibers

    Science.gov (United States)

    Fitts, R. H.; Bodine, S. C.; Romatowski, J. G.; Widrick, J. J.

    1998-01-01

    In this study, we determined the contractile properties of single chemically skinned fibers prepared from the medial gastrocnemius (MG) and soleus (Sol) muscles of adult male rhesus monkeys and assessed the effects of the spaceflight living facility known as the experiment support primate facility (ESOP). Muscle biopsies were obtained 4 wk before and immediately after an 18-day ESOP sit, and fiber type was determined by immunohistochemical techniques. The MG slow type I fiber was significantly smaller than the MG type II, Sol type I, and Sol type II fibers. The ESOP sit caused a significant reduction in the diameter of type I and type I/II (hybrid) fibers of Sol and MG type II and hybrid fibers but no shift in fiber type distribution. Single-fiber peak force (mN and kN/m2) was similar between fiber types and was not significantly different from values previously reported for other species. The ESOP sit significantly reduced the force (mN) of Sol type I and MG type II fibers. This decline was entirely explained by the atrophy of these fiber types because the force per cross-sectional area (kN/m2) was not altered. Peak power of Sol and MG fast type II fiber was 5 and 8.5 times that of slow type I fiber, respectively. The ESOP sit reduced peak power by 25 and 18% in Sol type I and MG type II fibers, respectively, and, for the former fiber type, shifted the force-pCa relationship to the right, increasing the Ca2+ activation threshold and the free Ca2+ concentration, eliciting half-maximal activation. The ESOP sit had no effect on the maximal shortening velocity (Vo) of any fiber type. Vo of the hybrid fibers was only slightly higher than that of slow type I fibers. This result supports the hypothesis that in hybrid fibers the slow myosin heavy chain would be expected to have a disproportionately greater influence on Vo.

  2. Ca2+_, Sr2+_force relationships and kinetic properties of fast-twitch rat leg muscle fibre subtypes.

    Science.gov (United States)

    Galler, S

    1999-10-01

    Force generation of fast-twitch and slow-twitch fibres exhibits large differences in its sensitivity to Ca2+ and Sr2+ (e.g. Fink et al. 1986). Little is known about fast-twitch fibre subtypes. Thus, a variety of mechanical measurements on segments of rehydrated freeze-dried fast-twitch rat leg muscle fibres were executed in this study. Among these, the Ca2+- and Sr2+-force relationship and the unloaded shortening velocity were determined. The fibres were classified into subtypes according to their kinetics of stretch activation (Galler et al. 1994). In all fibres, the maximal force under Sr2+ activation was about 0.9 of that under Ca2+ activation. The Ca2+- and Sr2+-force relationship exhibited a biphasic shape with a steeper part (Hill coefficient, n1) below 50% and a flatter part (Hill coefficient, n2) above 50% of maximal force. The difference between the Ca2+ - and Sr2+ -sensitivity was independent of the fibre subtypes. The Hill coefficients were only partially correlated with kinetic properties. The correlation was more pronounced for the unloaded shortening velocity than for the kinetics of stretch activation. The data are consistent with the idea that the Ca2+ and Sr2+ sensitivities of fast-twitch fibres are mainly determined by a single isoform of troponin C. Among several protein isoforms, the isoforms of the myosin light chains seem to be involved for determining the slope of the Ca2+- and Sr2+-force relationship of fast-twitch muscle fibres.

  3. Force transducers based on the stress dependence of coercive force

    Science.gov (United States)

    Garshelis, I. J.

    1993-05-01

    An alternative measurement regime for magnetoelastic force transducers, based on variations in coercive field, is described. Hc is shown to be more directly related to the primary magnetic influence of stress, namely, the orientation of effective anisotropy, than conventionally used magnetization related parameters. The stress dependence of Hc is shown to generally reflect opposing factors associated with rotational and wall displacement magnetization reversal processes. In materials wherein Hc≪K/Ms wall motion dominates and if the product of λs/K and yield stress is high enough, large monotonic reductions of Hc with positive (tensile) stress are shown to be possible. A more complex variation of Hc with increasing compression is similarly expected. Experimental results from a transducer having an 18% Ni maraging steel core support these expectations.

  4. Effects of the tensor force on the ground and first $2^{+}$ states of the magic $^{54}$Ca nucleus

    CERN Document Server

    Yüksel, E; Khan, E; Bozkurt, K

    2014-01-01

    The magic nature of the $^{54}$Ca nucleus is investigated in the light of the recent experimental results. We employ both HFB and HF+BCS methods using Skyrme-type SLy5, SLy5+T and T44 interactions. The evolution of the single-particle spectra is studied for the N=34 isotones: $^{60}$Fe, $^{58}$Cr, $^{56}$Ti and $^{54}$Ca. An increase is obtained in the neutron spin-orbit splittings of $p$ and $f$ states due to the effect of the tensor force which also makes $^{54}$Ca a magic nucleus candidate. QRPA calculations on top of HF+BCS are performed to investigate the first $J^{\\pi}$=$2^{+}$ states of the calcium isotopic chain. A good agreement for excitation energies is obtained when we include the tensor force in the mean-field part of the calculations. The first $2^{+}$ states indicate a subshell closure for both $^{52}$Ca and $^{54}$Ca nuclei. We confirm that the tensor part of the interaction is quite essential in explaining the neutron subshell closure in $^{52}$Ca and $^{54}$Ca nuclei.

  5. Secure electronic commerce communication system based on CA

    Science.gov (United States)

    Chen, Deyun; Zhang, Junfeng; Pei, Shujun

    2001-07-01

    In this paper, we introduce the situation of electronic commercial security, then we analyze the working process and security for SSL protocol. At last, we propose a secure electronic commerce communication system based on CA. The system provide secure services such as encryption, integer, peer authentication and non-repudiation for application layer communication software of browser clients' and web server. The system can implement automatic allocation and united management of key through setting up the CA in the network.

  6. The Implementation of School Based Continuous Assessment (CA) in Zambia

    Science.gov (United States)

    Kapambwe, William M.

    2010-01-01

    In Zambia, continuous assessment (CA) is defined as an on-going, diagnostic, classroom-based process that uses a variety of assessment tools to measure learner performance (MOE, 2005:5). Over the years, examinations have been used for selection and certification, without formal considerations on school-based continuous assessment as a component in…

  7. Environmental Impact Analysis Process. Environmental Impact Statement for the Closure of Mather Air Force Base

    Science.gov (United States)

    1990-03-01

    the California Health and Safety Code). The Department would like to be informed of future activities and use plans associated with the Muther AFB...Page 2 cc: Lt. Col Richard Blank Chief, Environmental Management 323rd Flying Training Wing Mather Air Force Base, CA 95655-5000 Lt. Col. Jose Saenz

  8. Tectonic forcing of early to middle jurassic seawater Sr/Ca

    DEFF Research Database (Denmark)

    Ullmann, Clemens Vinzenz; Hesselbo, Stephen P.; Korte, Christoph

    2013-01-01

    The Jurassic Period (ca. 201–145 Ma) is marked by fundamental reorganizations of paleogeography, paleoceanography, ecosystems, and the progressive shift from aragonite to calcite as the favored marine biogenic carbonate polymorph. Sr/Ca ratios of well-preserved Jurassic oysters and belemnites from...

  9. ANALOG I/O MODULE TEST SYSTEM BASED ON EPICS CA PROTOCOL AND ACTIVEX CA INTERFACE

    Energy Technology Data Exchange (ETDEWEB)

    YENG,YHOFF,L.

    2003-10-13

    Analog input (ADC) and output (DAC) modules play a substantial role in device level control of accelerator and large experiment physics control system. In order to get the best performance some features of analog modules including linearity, accuracy, crosstalk, thermal drift and so on have to be evaluated during the preliminary design phase. Gain and offset error calibration and thermal drift compensation (if needed) may have to be done in the implementation phase as well. A natural technique for performing these tasks is to interface the analog VO modules and GPIB interface programmable test instruments with a computer, which can complete measurements or calibration automatically. A difficulty is that drivers of analog modules and test instruments usually work on totally different platforms (vxworks VS Windows). Developing new test routines and drivers for testing instruments under VxWorks (or any other RTOS) platform is not a good solution because such systems have relatively poor user interface and developing such software requires substantial effort. EPICS CA protocol and ActiveX CA interface provide another choice, a PC and LabVIEW based test system. Analog 110 module can be interfaced from LabVIEW test routines via ActiveX CA interface. Test instruments can be controlled via LabVIEW drivers, most of which are provided by instrument vendors or by National Instruments. Labview also provides extensive data analysis and process functions. Using these functions, users can generate powerful test routines very easily. Several applications built for Spallation Neutron Source (SNS) Beam Loss Monitor (BLM) system are described in this paper.

  10. Development and evaluation of materials for thermochemical heat storage based on the CaO/CaCO3 reaction couple

    Science.gov (United States)

    Sakellariou, Kyriaki G.; Tsongidis, Nikolaos I.; Karagiannakis, George; Konstandopoulos, Athanasios G.; Baciu, Diana; Charalambopoulou, Georgia; Steriotis, Theodore; Stubos, Athanasios; Arlt, Wolfgang

    2016-05-01

    The current work relates to the development of synthetic calcium oxide (CaO) based compositions as candidate materials for energy storage under a cyclic carbonation/decarbonation reaction scheme. Although under such a cyclic scheme the energy density of natural lime based CaO is high (˜ 3MJ/kg), the particular materials suffer from notable cycle-to-cycle deactivation. To this direction, pure CaO and CaO/Al2O3 composites have been prepared and preliminarily evaluated under the suggested cyclic carbonation/decarbonation scheme in the temperature range of 600-800°C. For the composite materials, Ca/Al molar ratios were in the range between 95/5 and 52/48 and upon calcination the formation of mixed Ca/Al phases was verified. The preliminary evaluation of materials studied was conducted under 3 carbonation/decarbonation cycles and the loss of activity for the case of natural CaO was obvious. Synthetic materials with superior stability/capture c.f. natural CaO were further subjected to multi-cyclic carbonation/decarbonation, via which the positive effect of alumina addition was made evident. Selected compositions exhibited adequately high CO2 capture capacity and stable performance during multi-cyclic operation. Moreover, this study contains preliminary experiments referring to proof-of-principle validation of a concept based on the utilization of a CaO-based honeycomb reactor/heat exchanger preliminary design. In particular, cordierite monolithic structures were coated with natural CaO and in total 11 cycles were conducted. Upon operation, clear signs of heat dissipation by the imposed flow in the duration of the exothermic reaction step were identified.

  11. Properties of Ca-rich and Mg-rich carbonate films on dolomite: implications for compositional surface mapping with scanning force microscopy.

    Science.gov (United States)

    Hu, Xiaoming; Cubillas, Pablo; Higgins, Steven R

    2010-04-06

    A self-limited monolayer grown on dolomite (CaMg(CO(3))(2)), showing distinct friction contrast with the substrate as reported earlier using lateral force microscopy, was investigated with in situ atomic force microscopy (AFM) adhesion mapping and force-modulation techniques. Force-modulation microscopy revealed lower stiffness on a Ca-rich film in comparison to that on the dolomite surface. The friction contrast therefore results from a larger tip-surface contact area when the AFM probe is in contact with the Ca-rich film as opposed to the contact area with dolomite. The Ca-rich film also exhibited a slightly higher adhesion than did the dolomite substrate; however, the critical shear stresses for the two tip-surface contacts were indistinguishable. A comparative study with a Mg-rich film did not yield noticeable force modulation contrast, indicating similar surface stiffness of the film and the dolomite surface. The similarity in these stiffness quantities was further corroborated by friction-load data that demonstrated similar friction forces on the two surfaces. The previously reported film strain in the Ca-rich system is likely linked to the lower stiffness observed, with both of these properties related to the Ca/Mg composition of the film.

  12. MR compatible strain gauge based force transducer

    NARCIS (Netherlands)

    van Duinen, Hiske; Post, Marijn; Vaartjes, Koen; Hoogduin, Hans; Zijdewind, Inge

    2007-01-01

    In order to evaluate brain activation during motor tasks accurately one must also measure output parameters such as muscle force or muscle activity. Especially in clinical situations where the force output can be compromised by changes at different levels of the motor system, it is essential to stan

  13. MR compatible strain gauge based force transducer

    NARCIS (Netherlands)

    van Duinen, Hiske; Post, Marijn; Vaartjes, Koen; Hoogduin, Hans; Zijdewind, Inge

    2007-01-01

    In order to evaluate brain activation during motor tasks accurately one must also measure output parameters such as muscle force or muscle activity. Especially in clinical situations where the force output can be compromised by changes at different levels of the motor system, it is essential to stan

  14. Lorentz Force Based Satellite Attitude Control

    Science.gov (United States)

    Giri, Dipak Kumar; Sinha, Manoranjan

    2016-07-01

    Since the inception of attitude control of a satellite, various active and passive control strategies have been developed. These include using thrusters, momentum wheels, control moment gyros and magnetic torquers. In this present work, a new technique named Lorentz force based Coulombic actuators for the active control is proposed. This method uses electrostatic charged shells, which interact with the time varying earth's magnetic field to establish a full three axes control of the satellite. It is shown that the proposed actuation mechanism is similar to a satellite actuated by magnetic coils except that the resultant magnetic moment vanishes under two different conditions. The equation for the required charges on the the Coulomb shells attached to the satellite body axes is derived, which is in turn used to find the available control torque for actuating the satellite along the orbit. Stability of the proposed system for very high initial angular velocity and exponential stability about the origin are proved for a proportional-differential control input. Simulations are carried out to show the efficacy of the proposed system for the attitude control of the earth-pointing satellite.

  15. Synthesis of crystalline Si-based nanosheets by extraction of Ca from CaSi2 in inositol hexakisphosphate solution

    Science.gov (United States)

    Meng, Xiang; Sasaki, Kenta; Sano, Koki; Yuan, Peiling; Tatsuoka, Hirokazu

    2017-05-01

    Crystalline Si-based nanosheets were successfully synthesized from CaSi2 by a simple soft chemical synthetic method in solution. By immersing CaSi2 powder or CaSi2/Si substrates in an inositol hexakisphosphate (IP6) solution, Ca atoms were extracted from the CaSi2 particles, then Si-based nanosheets were formed. The morphological, structural and optical properties of the Si-based nanosheets were investigated. It is noted that the thin Si-based nanosheets stacked with a void space formed bundle structures, and the nanosheets were easily exfoliated from the bundles to expose the surfaces corresponding to the Si{111} planes. Meanwhile, the surface of the Si nanosheets might be terminated by O, H, or OH bonds. The Si-based nanosheet bundles were then formed and directly rooted to the Si(111) substrates, and had a remarkably highly symmetrical morphology. This study demonstrated a simple method for preparing Si-based nanosheets, and electro- and photo-chemical applications would possibly be expected, such as in lithium ion batteries.

  16. Impact of volcanism on the evolution of Lake Van (eastern Anatolia) III: Periodic (Nemrut) vs. episodic (Süphan) explosive eruptions and climate forcing reflected in a tephra gap between ca. 14 ka and ca. 30 ka

    Science.gov (United States)

    Schmincke, Hans-Ulrich; Sumita, Mari

    2014-09-01

    Fifteen Lateglacial to Holocene rhyolitic, dominantly primary tephra layers piston-cored and drilled (ICDP Paleovan drilling project) in western Lake Van (eastern Anatolia, Turkey) were precisely correlated to either of the two adjacent and active large volcanoes Nemrut and Süphan based on shard textures, mineralogy and mineral and glass compositions. The young peralkaline (comenditic to pantelleritic) primary rhyolitic Nemrut tephras are characterized by anorthoclase, hedenbergitic to augitic clinopyroxene, fayalitic olivine, minor quartz, and rare accessory chevkinite and zircon. Phenocrysts in subalkaline primary rhyolitic Süphan tephras are chiefly oligoclase-labradorite, with minor K-rich sanidine in some, biotite, amphibole, hypersthene, rare augitic clinopyroxene, relatively common allanite and rare zircon. Two contrasting explosive eruptive modes are distinguished from each other: episodic (Süphan) and periodic (Nemrut). The Lateglacial Süphan tephra swarm covers a short time interval of ca. 338 years between ca. 13,078 vy BP and 12,740 vy BP, eruptions having occurred statistically every ca. 42 years with especially short intervals between V-11 (reworked) and V-14. Causes for the strongly episodic Süphan explosive behavior might include seismic triggering of a volcano-magma system unable to erupt explosively without the benefit of external triggering, as reflected in pervasive faulting preceding the Süphan tephra swarm. Seismic triggering may have caused the rise of more mafic ("trachyandesitic") parent magma, heating near-surface pockets of highly evolved magma - that might have formed silicic domes during this stage of volcano evolution - resulting in ascent and finally explosive fragmentation of magma essentially by external factors, probably significantly enhanced by magma-water/ice interaction. Explosive eruptions of the Nemrut volcano system, interpreted to be underlain by a large fractionating magma reservoir, follow a more periodic mode of (a

  17. Athermalization in atomic force microscope based force spectroscopy using matched microstructure coupling.

    Science.gov (United States)

    Torun, H; Finkler, O; Degertekin, F L

    2009-07-01

    The authors describe a method for athermalization in atomic force microscope (AFM) based force spectroscopy applications using microstructures that thermomechanically match the AFM probes. The method uses a setup where the AFM probe is coupled with the matched structure and the displacements of both structures are read out simultaneously. The matched structure displaces with the AFM probe as temperature changes, thus the force applied to the sample can be kept constant without the need for a separate feedback loop for thermal drift compensation, and the differential signal can be used to cancel the shift in zero-force level of the AFM.

  18. Minimum Normal Force Principle Based Quantitive Optimizationof Clamping Forces for Thin Walled Part

    Institute of Scientific and Technical Information of China (English)

    ZHANG Fa-ping; SUN Hou-fang; SHAHID I.Butt

    2008-01-01

    Based on the stability criteria of workpiece-fixture system, quantitative optimization of clamping forces during precise machining process for thin walled part is studied considering the contact condition between wokpiece and locator, the contact mechanical model is achieved ,which is further been used to calculate the entire passive forces acting on the statically undetermined workpiece by means of the force screw theory as well as minimum norm force principle. Furthermore, a new methodology to optimize clamping forces is put forward, on the criteria of keeping the stability of workpiece during cutting process. By this way, the intensity of clamping forces is decreased dramatically, which will be most beneficial for improving the machining quality of thin-walled parts. Finally, a case study is used to support and validate the proposed model.

  19. Circuit Design of Surface Acoustic Wave Based Micro Force Sensor

    Directory of Open Access Journals (Sweden)

    Yuanyuan Li

    2014-01-01

    Full Text Available Pressure sensors are commonly used in industrial production and mechanical system. However, resistance strain, piezoresistive sensor, and ceramic capacitive pressure sensors possess limitations, especially in micro force measurement. A surface acoustic wave (SAW based micro force sensor is designed in this paper, which is based on the theories of wavelet transform, SAW detection, and pierce oscillator circuits. Using lithium niobate as the basal material, a mathematical model is established to analyze the frequency, and a peripheral circuit is designed to measure the micro force. The SAW based micro force sensor is tested to show the reasonable design of detection circuit and the stability of frequency and amplitude.

  20. Security Considerations Based on PKI/CA in Manufacturing Grid

    Institute of Scientific and Technical Information of China (English)

    YIN Yong; LI Yu

    2006-01-01

    In the manufacturing grid environment, the span of the consideration of security issues is more extensive, and the solutions for them are more complex, therefore these problems in manufacturing grid can't longer be addressed by existing security technologies. In order to solve this problem, the paper first puts forward the security architecture of manufacturing grid on the basis of the proposal of the security strategies for manufacturing grid; then the paper introduces key technologies based on public key infrastructure-certificate authority (PKI/CA) to ensure the security of manufacturing grid, such as single sign-on, security proxy, independent authentication and so on. Schemes discussed in the paper have some values to settle security problems in the manufacturing grid environment.

  1. Linear thermal circulator based on Coriolis forces.

    Science.gov (United States)

    Li, Huanan; Kottos, Tsampikos

    2015-02-01

    We show that the presence of a Coriolis force in a rotating linear lattice imposes a nonreciprocal propagation of the phononic heat carriers. Using this effect we propose the concept of Coriolis linear thermal circulator which can control the circulation of a heat current. A simple model of three coupled harmonic masses on a rotating platform permits us to demonstrate giant circulating rectification effects for moderate values of the angular velocities of the platform.

  2. Study of Slope Reinforcement Force Based on FLAC

    Institute of Scientific and Technical Information of China (English)

    HUANG Xian-wu; MAO xian-biao; MIAO Xie-xing; CHEN Zhan-qing

    2006-01-01

    A slope will slide if the unbalanced force does not tend to zero when the stability of the slope is analyzed with the help of FLAC. Thus the ultimate reason of slope sliding is the unbalanced force determined by FLAC. The slope will remain stable if the unbalanced force is counterbalanced by a reinforcement force which is produced by a suitable reinforcement method. In this paper, the stability of the slope was analyzed by using FLAC, and the unbalanced force of the slope was obtained through the FISH function in FLAC. According to the equilibrium conditions, the relationship between the reinforcement force and unbalanced force was derived and accordingly the reinforcement force was determined. The reinforcement design was adopted by using pre-stressed anchor bars on the basis of the reinforcement force. An example is used to show that the effect of slope reinforcement based on the reinforcement force is safe and economical. The method doesn't need to suppose a sliding surface to obtain the reinforcement force, and it is also clear in physical meaning. So this method realized the organic unification of the stability analysis and the slope reinforcement

  3. An Optimization-Based Impedance Approach for Robot Force Regulation with Prescribed Force Limits

    Directory of Open Access Journals (Sweden)

    R. de J. Portillo-Vélez

    2015-01-01

    Full Text Available An optimization based approach for the regulation of excessive or insufficient forces at the end-effector level is introduced. The objective is to minimize the interaction force error at the robot end effector, while constraining undesired interaction forces. To that end, a dynamic optimization problem (DOP is formulated considering a dynamic robot impedance model. Penalty functions are considered in the DOP to handle the constraints on the interaction force. The optimization problem is online solved through the gradient flow approach. Convergence properties are presented and the stability is drawn when the force limits are considered in the analysis. The effectiveness of our proposal is validated via experimental results for a robotic grasping task.

  4. Force Based Skill Learning for Robot Tasks in Contact Conditions

    Institute of Scientific and Technical Information of China (English)

    王琴; 梅志千; 张广立; 杨汝清

    2004-01-01

    To acquire human operation skill based on force sense, element contact form (ECF) is proposed to describe contact condition firstly. The skill is modeled as a sequence of discrete ECFs. Since different ECF has different force distribution, a support vector machine classifier is built to identify the contact conditions according to the force signal. Finally, the robot can obtain the skill from the human demonstration.

  5. Force

    CERN Document Server

    Graybill, George

    2007-01-01

    Forces are at work all around us. Discover what a force is, and different kinds of forces that work on contact and at a distance. We use simple language and vocabulary to make this invisible world easy for students to ""see"" and understand. Examine how forces ""add up"" to create the total force on an object, and reinforce concepts and extend learning with sample problems.

  6. Wright-Patterson Air Force Base: The First Century

    Science.gov (United States)

    2015-01-01

    Patterson Swimming Pool Lt Frank Stuart Patterson Pool 1936 Wright Memorial Wilbur and Orville Wright Monument 1940 Thurlow Street Col Thomas L...WRIGHT-PATTERSON AIR FORCE BASE: The First Century ii History Office Air Force Life Cycle...origins to World War I, its aviation history began with the origins of manned, powered, controlled flight. Following their successful proof-of

  7. Transparent and flexible force sensor array based on optical waveguide.

    Science.gov (United States)

    Kim, Youngsung; Park, Suntak; Park, Seung Koo; Yun, Sungryul; Kyung, Ki-Uk; Sun, Kyung

    2012-06-18

    This paper suggests a force sensor array measuring contact force based on intensity change of light transmitted throughout optical waveguide. For transparency and flexibility of the sensor, two soft prepolymers with different refractive index have been developed. The optical waveguide consists of two cladding layers and a core layer. The top cladding layer is designed to allow light scattering at the specific area in response to finger contact. The force sensor shows a distinct tendency that output intensity decreases with input force and measurement range is from 0 to -13.2 dB.

  8. Information-based physics, influence, and forces

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, James Lyons [Department of Physics, University at Albany (SUNY) (United States); Knuth, Kevin H. [Department of Physics, University at Albany (SUNY) and Department of Informatics, University at Albany (SUNY) (United States)

    2015-01-13

    In recent works, Knuth and Bahreyni have demonstrated that the concepts of space and time are emergent in a coarse-grained model of direct particle-particle influence. In addition, Knuth demonstrated that observer-made inferences regarding the free particle, which is defined as a particle that influences others, but is not itself influenced, result in a situation identical to the Feynman checkerboard model of the Dirac equation. This suggests that the same theoretical framework that gives rise to an emergent spacetime is consistent with quantum mechanics. In this paper, we begin to explore the effect of influence on the emergent properties of a particle. This initial study suggests that when a particle is influenced, it is interpreted as accelerating in a manner consistent with special relativity implying that, at least in this situation, influence can be conceived of as a force.

  9. Information-based physics, influence, and forces

    Science.gov (United States)

    Walsh, James Lyons; Knuth, Kevin H.

    2015-01-01

    In recent works, Knuth and Bahreyni have demonstrated that the concepts of space and time are emergent in a coarse-grained model of direct particle-particle influence. In addition, Knuth demonstrated that observer-made inferences regarding the free particle, which is defined as a particle that influences others, but is not itself influenced, result in a situation identical to the Feynman checkerboard model of the Dirac equation. This suggests that the same theoretical framework that gives rise to an emergent spacetime is consistent with quantum mechanics. In this paper, we begin to explore the effect of influence on the emergent properties of a particle. This initial study suggests that when a particle is influenced, it is interpreted as accelerating in a manner consistent with special relativity implying that, at least in this situation, influence can be conceived of as a force.

  10. FORCE FEEDBACK DATAGLOVE BASED ON PNEUMATIC ARTIFICIAL MUSCLES

    Institute of Scientific and Technical Information of China (English)

    BAO Gang; SUN Zhongsheng; WANG Zuwen

    2006-01-01

    An exoskeleton force feedback dataglove is developed, which uses the pneumatic artificial muscles as actuators. On the basis of the simplified hand model, the motion equation is deduced according to the theory of Denavit-Hartenberg. The model of the equivalent contact forces exerted by the object on the finger is proposed. By the principle of virtual work, the static equilibrium of finger is established. The force Jacobian matrix of finger is calculated, and then the joint torques of the finger when grasping objects are obtained. The theory and structure of the force feedback datagolve are introduced. Based on the theory of motion stabilization of four-bar linkage, the flexion angles of joints are measured. The torques on finger joints caused by the output forces of pneumatic artificial muscles are calculated. The output forces of pneumatic artificial muscle, whose values are controlled by its inner pressure, can be calculated by the joint torques ofthe finger when grasping objects. The arms of force, driving torques and the needed output forces of pneumatic muscle are calculated for each joint of the index finger. The criterion of output force of pneumatic muscle is given.

  11. Role of cyclic nucleotide-dependent actin cytoskeletal dynamics:Ca(2+](i and force suppression in forskolin-pretreated porcine coronary arteries.

    Directory of Open Access Journals (Sweden)

    Kyle M Hocking

    Full Text Available Initiation of force generation during vascular smooth muscle contraction involves a rise in intracellular calcium ([Ca(2+]i and phosphorylation of myosin light chains (MLC. However, reversal of these two processes alone does not account for the force inhibition that occurs during relaxation or inhibition of contraction, implicating that other mechanisms, such as actin cytoskeletal rearrangement, play a role in the suppression of force. In this study, we hypothesize that forskolin-induced force suppression is dependent upon changes in actin cytoskeletal dynamics. To focus on the actin cytoskeletal changes, a physiological model was developed in which forskolin treatment of intact porcine coronary arteries (PCA prior to treatment with a contractile agonist resulted in complete suppression of force. Pretreatment of PCA with forskolin suppressed histamine-induced force generation but did not abolish [Ca(2+]i rise or MLC phosphorylation. Additionally, forskolin pretreatment reduced filamentous actin in histamine-treated tissues, and prevented histamine-induced changes in the phosphorylation of the actin-regulatory proteins HSP20, VASP, cofilin, and paxillin. Taken together, these results suggest that forskolin-induced complete force suppression is dependent upon the actin cytoskeletal regulation initiated by the phosphorylation changes of the actin regulatory proteins and not on the MLC dephosphorylation. This model of complete force suppression can be employed to further elucidate the mechanisms responsible for smooth muscle tone, and may offer cues to pathological situations, such as hypertension and vasospasm.

  12. Platform-based Shear Force Sensor

    Directory of Open Access Journals (Sweden)

    Wang Wei-Chih

    2015-01-01

    Full Text Available In this paper, we will present the development of a flexible fiber optic bend loss sensor for the measurement of plantar pressure and shear stress for diabetic patients. The sensor will allow the measurement of shear stress on the foot, which is a critical parameter in studying diabetic foot ulcers. The basic configuration of the optical sensor systems incorporates a mesh that is comprised of two sets of parallel optical waveguide planes; the planes are configured so the parallel rows of waveguides of the top and bottom planes are perpendicular to each other. The planes are sandwiched together creating one sensing sheet. Two-dimensional information is determined by measuring the loss of light from each of the waveguide to map the overall pressure distribution. The shifting of the layers relative to each other produces different patterns of the sensor output, and shear force information is characterized through repeated training of the sensor and analysis of the training data. The latest development and improvement in the sensors design is presented. Fabrication and sensor characterization results will be presented.

  13. Curtailment of soil vapor extraction systems at McClellan Air Force Base

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, T.E. [BDM Federal, McClellan AFB, CA (United States); Mook, P.H. Jr.; Wong, K.B. [SM-ALC/EMR, McClellan AFB, CA (United States)

    1997-12-31

    McClellan Air Force Base (AFB), located near Sacramento, California, is one of the Strategic Environmental Research and Development Program`s National Environmental Technology Test Sites. McClellan AFB has implemented soil vapor extraction (SVE) as an Engineering Evaluation/Cost Analysis (EE/CA) non-time-critical remedial action for volatile organic compounds in soil. Operation and maintenance costs for SVE systems are increasingly becoming a major component of the environmental clean-up budget. In an effort to reduce costs, while assuring the protection of public health and the environment, a risk-based strategy has been developed for the curtailment and eventual shut-down of SVE systems at McClellan AFB. This paper presents an overview of the SVE EE/CA process and a detailed description of the development and implementation of the curtailment strategy. Included in the discussion are details of the public and regulatory involvement in the process.

  14. External Force Estimation for Teleoperation Based on Proprioceptive Sensors

    Directory of Open Access Journals (Sweden)

    Enrique del Sol

    2014-03-01

    Full Text Available This paper establishes an approach to external force estimation for telerobotic control in radioactive environments by the use of an identified manipulator model and pressure sensors, without employing a force/torque sensor. The advantages of - and need for - force feedback have been well-established in the field of telerobotics, where electrical and back-drivable manipulators have traditionally been used. This research proposes a methodology employing hydraulic robots for telerobotics tasks based on a model identification scheme. Comparative results of a force sensor and the proposed approach using a hydraulic telemanipulator are presented under different conditions. This approach not only presents a cost effective solution but also a methodology for force estimation in radioactive environments, where the dose rates limit the use of electronic devices such as sensing equipment.

  15. Exploring the retention properties of CaF2 nanoparticles as possible additives for dental care application with tapping-mode atomic force microscope in liquid

    Directory of Open Access Journals (Sweden)

    Matthias Wasem

    2014-01-01

    Full Text Available Amplitude-modulation atomic force microscopy (AM-AFM is used to determine the retention properties of CaF2 nanoparticles adsorbed on mica and on tooth enamel in liquid. From the phase-lag of the forced cantilever oscillation the local energy dissipation at the detachment point of the nanoparticle was determined. This enabled us to compare different as-synthesized CaF2 nanoparticles that vary in shape, size and surface structure. CaF2 nanoparticles are candidates for additives in dental care products as they could serve as fluorine-releasing containers preventing caries during a cariogenic acid attack on the teeth. We show that the adherence of the nanoparticles is increased on the enamel substrate compared to mica, independently of the substrate roughness, morphology and size of the particles.

  16. Decay of Ca2+ and force transients in fast- and slow-twitch skeletal muscles from the rat, mouse and Etruscan shrew.

    Science.gov (United States)

    Wetzel, P; Gros, G

    1998-02-01

    Isometric single-twitch force and intracellular Ca2+ transients were recorded simultaneously, using fura-2, from slow- and fast-twitch muscle fibres of the rat, mouse and Etruscan shrew Suncus etruscus. In the slow-twitch rat soleus, force half-relaxation time was three times longer than the 50% decay time of the fura-2 signal. In contrast, in the fast-twitch extensor digitorum longus muscles of all three animals, muscle relaxation preceded Ca2+ decay. It is proposed that this surprising property of fast-twitch muscles is due to their pCa-tension curve, which is shifted to the right compared with that of slow-twitch muscle.

  17. 33 CFR 165.1120 - Security Zone; Naval Amphibious Base, San Diego, CA.

    Science.gov (United States)

    2010-07-01

    ... Base, San Diego, CA. 165.1120 Section 165.1120 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... § 165.1120 Security Zone; Naval Amphibious Base, San Diego, CA. (a) Location. The following area is a security zone: the waters of San Diego Bay, enclosed by lines connecting the following points: Beginning at...

  18. Improvements to Air Force Strategic Basing Decisions

    Science.gov (United States)

    2016-01-01

    installation’s available capacity for growth in water use, storm water handling, waste management, utility needs, energy production, local air pollutants , and...conditions, such as replacing a more polluting weapon system with a newer, less polluting one. Finally, interviewees argued that NEPA procedures need to be...running through the West Indies to South America and the other through Texas and Central America—composed of land and seaplane bases stretching from CONUS

  19. Dephosphorization Thermodynamics of Crude Steel Using CaO-Based Flux

    Institute of Scientific and Technical Information of China (English)

    YANG Yin-dong; McKague A R; McLean A; Sommerville I D

    2003-01-01

    The experiments were carried out at 1 175-1 450 ℃ to study the phosphorus distribution ratio between molten CaO-based slags and carbon saturated hot metal. The phosphate capacity of the slags and the activity coefficient of PO2.5 were calculated from the phosphorus distribution ratio. The effect of addition of CaF2 and/or CaCl2 on the thermodynamic properties of slags was discussed. The correlation of optical basicity with phosphate capacity of slags was studied, and the dephosphorization ability of CaO-based fluxes with various additives was compared with the results from different studies.

  20. REACTION KINETICS OF CA-BASED SORBENTS WITH HC1

    Science.gov (United States)

    The kinetics of the reaction between CaO and HCl were investigated under conditions that minimize bulk mass transfer and pore diffusion limitations. Reactivity data from 0.2- to 1-s exposure to 5000 ppm HCl in a fixed bed reactor were analyzed by a shrinking core model of diffusi...

  1. A force plate based method for the calibration of force/torque sensors.

    Science.gov (United States)

    Faber, Gert S; Chang, Chien-Chi; Kingma, Idsart; Schepers, H Martin; Herber, Sebastiaan; Veltink, Peter H; Dennerlein, Jack T

    2012-04-30

    This study describes a novel calibration method for six-degrees-of-freedom force/torque sensors (FTsensors) using a pre-calibrated force plate (FP) as a reference measuring device. In this calibration method, the FTsensor is rigidly connected to a FP and force/torque data are synchronously recorded while a dynamic functional loading procedure is applied by the researcher. Based on these data an accurate calibration matrix for the FTsensor can easily be obtained via least-squares optimization. Using this calibration method, this study further investigated what loading methods are appropriate for the calibration of FTsensors intended for ambulatory measurement of ground reaction forces (GRFs). Seven different loading methods were compared (e.g., walking, pushing while standing on the FTsensor). Calibration matrices were calculated based on the raw data from the seven loading methods individually and all loading methods combined. Performance of these calibration matrices was subsequently compared in an in situ trial. During the in situ trial, five common work tasks (e.g., walking, manual lifting, pushing) were performed by an experimenter, while standing on the FP wearing a "ForceShoe" with two calibrated FTsensors attached to its sole. Root-mean-square differences (RMSDs) between the FTsensor and FP outcomes were calculated over all tasks. Using the calibration matrices based on all loading methods combined resulted in small RMSDs (GRF: <8 N, center of pressure: <2 mm). Using the calibration matrices based on "pushing against manual resistance" resulted in similar RMSDs, proving it to be the best single loading method.

  2. On estimating the force-freeness based on observed magnetograms

    CERN Document Server

    Zhang, X M; Su, J T

    2016-01-01

    It is a common practice in the solar physics community to test whether or not measured photospheric or chromospheric vector magnetograms are force-free, using the Maxwell stress as a measure. Some previous studies have suggested that magnetic fields of active regions in the solar chromosphere are close to be force-free whereas there is no consistency among previous studies on whether magnetic fields of active regions in the solar photosphere are force-free or not. Here we use three kinds of representative magnetic fields (analytical force-free solutions, modeled solar-like force-free fields and observed non-force-free fields) to discuss on how the measurement issues such as limited field of view, instrument sensitivity and measurement error could affect the estimation of force-freeness based on observed magnetograms. Unlike previous studies that focus on discussing the effect of limited field of view or instrument sensitivity, our calculation shows that just measurement error alone can significantly influence...

  3. Micro-vibration-based slip detection in tactile force sensors.

    Science.gov (United States)

    Fernandez, Raul; Payo, Ismael; Vazquez, Andres S; Becedas, Jonathan

    2014-01-03

    Tactile sensing provides critical information, such as force, texture, shape or temperature, in manipulation tasks. In particular, tactile sensors traditionally used in robotics are emphasized in contact force determination for grasping control and object recognition. Nevertheless, slip detection is also crucial to successfully manipulate an object. Several approaches have appeared to detect slipping, the majority being a combination of complex sensors with complex algorithms. In this paper, we deal with simplicity, analyzing how a novel, but simple, algorithm, based on micro-vibration detection, can be used in a simple, but low-cost and durable, force sensor. We also analyze the results of using the same principle to detect slipping in other force sensors based on flexible parts. In particular, we show and compare the slip detection with: (i) a flexible finger, designed by the authors, acting as a force sensor; (ii) the finger torque sensor of a commercial robotic hand; (iii) a commercial six-axis force sensor mounted on the wrist of a robot; and (iv) a fingertip piezoresistive matrix sensor.

  4. Exploring Mg-Zn-Ca-Based Bulk Metallic Glasses for Biomedical Applications Based on Thermodynamic Approach

    Science.gov (United States)

    Ramya, M.; Sarwat, Syed Ghazi; Udhayabanu, V.; Raj, Baldev; Ravi, K. R.

    2015-12-01

    Magnesium (Mg)-based metallic glasses are considered as possible candidates in orthopedic implant applications. This paper aims to theoretically predict the glass-forming ability (GFA) in Mg-Zn-Ca alloy using a newly proposed thermodynamic model ( P HHS), and the consistency of this model is verified through experimental analysis. P HHS is based on thermodynamic parameters such as enthalpy of chemical mixing, elastic enthalpy, and configurational entropy, thus incorporating the pivotal effects, i.e., electron transfer effects, effect of atomic size mismatch, and effect of randomness, which aid to high GFA. In essence, P HHS can be visualized as the energy barrier that exists between the transformations of random atomic structure of glass to ordered crystalline structure. When the P HHS value is more negative, the energy barrier will be high, supporting easy glass formation. Various Mg-Zn-Ca metallic glass compositions displayed almost an expected and supporting trend, where the critical diameter of the metallic glass rod increased with a more negative P HHS value. Among the predicted Mg-Zn-Ca systems, the Mg60Zn35Ca5 composition shows deviation from the expected trend. This discrepancy has been clearly elucidated using a eutectic phase diagram. In addition to the consistency of the P HHS parameter to verifying the GFA of various compositions, the unique ability of this model is to predict unexplored Mg-Zn-Ca glass-forming compositions using contour development. Thus, proving P HHS parameter to be used as an efficient tool in predicting new glass-forming compositions.

  5. Longitudinal tire force estimation based on sliding mode observer

    Energy Technology Data Exchange (ETDEWEB)

    El Hadri, A.; Cadiou, J.C.; M' Sirdi, N.K. [Versailles Univ., Paris (France). Lab. de Robotique; Beurier, G.; Delanne, Y. [Lab. Central des Ponts, Centre de Nantes (France)

    2001-07-01

    This paper presents an estimation method for vehicle longitudinal dynamics, particularly the tractive/braking force. The estimation can be used to detect a critical driving situation to improve security. It can be used also in several vehicle control systems. The main characteristics of the vehicle longitudinal dynamics were taken into account in the model used to design an observer and computer simulations. The state variables are the angular wheel velocity, vehicle velocity and the longitudinal tire force. The proposed differential equation of the tractive/braking force is derived using the concept of relaxation length. The observer designed is based on the sliding mode approach using only the angular wheel velocity measurement. The proposed method of estimation is verified through a one-wheel simulation model with a ''Magic formula'' tire model. Simulations results show an excellent reconstruction of the tire force. (orig.)

  6. Oscillatory and ion-correlation forces observed in direct force measurements between silica surfaces in concentrated CaCl2 solutions

    NARCIS (Netherlands)

    Fielden, ML; Hayes, RA; Ralston, J

    2000-01-01

    The force between silica spheres and naturally oxidised silicon wafer has been measured in calcium chloride solutions at concentrations between 1 and 5 M using an atomic force microscope. An oscillatory force, consistent in periodicity with the expulsion of layers of ions, was found to overlay the e

  7. Jamming transitions in force-based models for pedestrian dynamics

    CERN Document Server

    Chraibi, Mohcine; Tordeux, Antoine; Nishinari, Katsuhiro; Schadschneider, Andreas; Seyfried, Armin

    2015-01-01

    Force-based models describe pedestrian dynamics in analogy to classical mechanics by a system of second order ordinary differential equations. By investigating the linear stability of two main classes of forces, parameter regions with unstable homogeneous states are identified. In this unstable regime it is then checked whether phase transitions or stop-and-go waves occur. Results based on numerical simulations show, however, that the investigated models lead to unrealistic behavior in form of backwards moving pedestrians and overlapping. This is one reason why stop-and-go waves have not been observed in these models. The unrealistic behavior is not related to the numerical treatment of the dynamic equations but rather indicates an intrinsic problem of this model class. Identifying the underlying generic problems gives indications how to define models that do not show such unrealistic behavior. As an example we introduce a new force-based model which produces realistic jam dynamics without the appearance of u...

  8. iCaCoT: Interactive camera-based coaching and training

    NARCIS (Netherlands)

    D'Acunto, L.; Redi, J.A.; Niamut, O.A.

    2015-01-01

    This paper reports on the evaluation of the concept of interactive camera-based coaching and training (iCaCoT), which focuses on using interactive video navigation for coaching and training purposes. The iCaCoT concept leverages tiled streaming technology, which allows users to navigate freely throu

  9. iCaCoT - Interactive Camera-based Coaching and Training

    NARCIS (Netherlands)

    D’Acunto, L.; Redi, J.; Niamut, O.A.

    2015-01-01

    This paper reports on the evaluation of the concept of interactive camera-based coaching and training (iCaCoT), which focuses on using interactive video navigation for coaching and training purposes. The iCaCoT concept leverages tiled streaming technology, which allows users to navigate freely

  10. Adaptive Central Force Optimization Algorithm Based on the Stability Analysis

    Directory of Open Access Journals (Sweden)

    Weiyi Qian

    2015-01-01

    Full Text Available In order to enhance the convergence capability of the central force optimization (CFO algorithm, an adaptive central force optimization (ACFO algorithm is presented by introducing an adaptive weight and defining an adaptive gravitational constant. The adaptive weight and gravitational constant are selected based on the stability theory of discrete time-varying dynamic systems. The convergence capability of ACFO algorithm is compared with the other improved CFO algorithm and evolutionary-based algorithm using 23 unimodal and multimodal benchmark functions. Experiments results show that ACFO substantially enhances the performance of CFO in terms of global optimality and solution accuracy.

  11. System of gait analysis based on ground reaction force assessment

    Directory of Open Access Journals (Sweden)

    František Vaverka

    2015-12-01

    Full Text Available Background: Biomechanical analysis of gait employs various methods used in kinematic and kinetic analysis, EMG, and others. One of the most frequently used methods is kinetic analysis based on the assessment of the ground reaction forces (GRF recorded on two force plates. Objective: The aim of the study was to present a method of gait analysis based on the assessment of the GRF recorded during the stance phase of two steps. Methods: The GRF recorded with a force plate on one leg during stance phase has three components acting in directions: Fx - mediolateral, Fy - anteroposterior, and Fz - vertical. A custom-written MATLAB script was used for gait analysis in this study. This software displays instantaneous force data for both legs as Fx(t, Fy(t and Fz(t curves, automatically determines the extremes of functions and sets the visual markers defining the individual points of interest. Positions of these markers can be easily adjusted by the rater, which may be necessary if the GRF has an atypical pattern. The analysis is fully automated and analyzing one trial takes only 1-2 minutes. Results: The method allows quantification of temporal variables of the extremes of the Fx(t, Fy(t, Fz(t functions, durations of the braking and propulsive phase, duration of the double support phase, the magnitudes of reaction forces in extremes of measured functions, impulses of force, and indices of symmetry. The analysis results in a standardized set of 78 variables (temporal, force, indices of symmetry which can serve as a basis for further research and diagnostics. Conclusions: The resulting set of variable offers a wide choice for selecting a specific group of variables with consideration to a particular research topic. The advantage of this method is the standardization of the GRF analysis, low time requirements allowing rapid analysis of a large number of trials in a short time, and comparability of the variables obtained during different research measurements.

  12. A Biophysically Based Mathematical Model for the Kinetics of Mitochondrial Na+-Ca2+ Antiporter

    Science.gov (United States)

    Pradhan, Ranjan K.; Beard, Daniel A.; Dash, Ranjan K.

    2010-01-01

    Sodium-calcium antiporter is the primary efflux pathway for Ca2+ in respiring mitochondria, and hence plays an important role in mitochondrial Ca2+ homeostasis. Although experimental data on the kinetics of Na+-Ca2+ antiporter are available, the structure and composition of its functional unit and kinetic mechanisms associated with the Na+-Ca2+ exchange (including the stoichiometry) remains unclear. To gain a quantitative understanding of mitochondrial Ca2+ homeostasis, a biophysical model of Na+-Ca2+ antiporter is introduced that is thermodynamically balanced and satisfactorily describes a number of independent data sets under a variety of experimental conditions. The model is based on a multistate catalytic binding mechanism for carrier-mediated facilitated transport and Eyring's free energy barrier theory for interconversion and electrodiffusion. The model predicts the activating effect of membrane potential on the antiporter function for a 3Na+:1Ca2+ electrogenic exchange as well as the inhibitory effects of both high and low pH seen experimentally. The model is useful for further development of mechanistic integrated models of mitochondrial Ca2+ handling and bioenergetics to understand the mechanisms by which Ca2+ plays a role in mitochondrial signaling pathways and energy metabolism. PMID:20338843

  13. STS-67 landing at Edwards Air Force Base

    Science.gov (United States)

    1995-01-01

    The drag chute is fully deployed in this view of the Space Shuttle Endeavour as it completes a mission of almost 17 days duration in space on runway 22 at Edwards Air Force Base in southern California. Landing occurred at 1:46 p.m. (EST), March 18, 1995.

  14. STS-66 landing at Edwards Air Force Base

    Science.gov (United States)

    1994-01-01

    The main landing gear is on the ground and the nose gear is about to touch down as the Space Shuttle Atlantis heads toward a stop at Edwards Air Force Base in southern California, ending a successful 10 day, 22 hour and 34 minute space mission. Landing occured at 7:34 a.m. (PST), November 14, 1994.

  15. The Campus-Based Formula. NASFAA Task Force Report

    Science.gov (United States)

    National Association of Student Financial Aid Administrators, 2014

    2014-01-01

    The primary purpose of the National Association of Student Financial Aid Administrators (NASFAA) Campus-Based Aid Allocation Task Force was to examine the formula by which congressional appropriations for the Federal Supplemental Educational Opportunity Grant (FSEOG), Federal Work-Study (FWS), and Perkins Loan programs are distributed to schools,…

  16. San Antonio Creek Restoration, Vandenberg Air Force Base, California

    Science.gov (United States)

    2008-06-27

    constrictor Racer Potential Masticophis lateralis Chaparral whipsnake Potential Lampropeltis getula California kingsnake Observed Pituophis catenifer...Unpublished master’s thesis, University of California , Santa Barbara. Grant, C. 1978a. Chumash: Introduction . In California , edited by Robert F. Heizer, pp...Final Draft Environmental Assessment San Antonio Creek Restoration Vandenberg Air Force Base California

  17. Model based control of dynamic atomic force microscope

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chibum [Department of Mechanical System Design Engineering, Seoul National University of Science and Technology, Seoul 139-743 (Korea, Republic of); Salapaka, Srinivasa M., E-mail: salapaka@illinois.edu [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

    2015-04-15

    A model-based robust control approach is proposed that significantly improves imaging bandwidth for the dynamic mode atomic force microscopy. A model for cantilever oscillation amplitude and phase dynamics is derived and used for the control design. In particular, the control design is based on a linearized model and robust H{sub ∞} control theory. This design yields a significant improvement when compared to the conventional proportional-integral designs and verified by experiments.

  18. Model based control of dynamic atomic force microscope.

    Science.gov (United States)

    Lee, Chibum; Salapaka, Srinivasa M

    2015-04-01

    A model-based robust control approach is proposed that significantly improves imaging bandwidth for the dynamic mode atomic force microscopy. A model for cantilever oscillation amplitude and phase dynamics is derived and used for the control design. In particular, the control design is based on a linearized model and robust H(∞) control theory. This design yields a significant improvement when compared to the conventional proportional-integral designs and verified by experiments.

  19. Energy storage for a lunar base by the reversible chemical reaction: CaO+H2O reversible reaction Ca(OH)2

    Science.gov (United States)

    Perez-Davis, Marla E.; Difilipo, Frank

    1990-01-01

    A thermochemical solar energy storage concept involving the reversible reaction CaO + H2O yields Ca(OH)2 is proposed as a power system element for a lunar base. The operation and components of such a system are described. The CaO/H2O system is capable of generating electric power during both the day and night. The specific energy (energy to mass ratio) of the system was estimated to be 155 W-hr/kg. Mass of the required amount of CaO is neglected since it is obtained from lunar soil. Potential technical problems, such as reactor design and lunar soil processing, are reviewed.

  20. Capillary and van der Waals interactions on CaF2 crystals from amplitude modulation AFM force reconstruction profiles under ambient conditions

    Directory of Open Access Journals (Sweden)

    Annalisa Calò

    2015-03-01

    Full Text Available There has been much interest in the past two decades to produce experimental force profiles characteristic of the interaction between nanoscale objects or a nanoscale object and a plane. Arguably, the advent of the atomic force microscope AFM was instrumental in driving such efforts because, in principle, force profiles could be recovered directly. Nevertheless, it has taken years before techniques have developed enough as to recover the attractive part of the force with relatively low noise and without missing information on critical ranges, particularly under ambient conditions where capillary interactions are believed to dominate. Thus a systematic study of the different profiles that may arise in such situations is still lacking. Here we employ the surfaces of CaF2, on which nanoscale water films form, to report on the range and force profiles that might originate by dynamic capillary interactions occurring between an AFM tip and nanoscale water patches. Three types of force profiles were observed under ambient conditions. One in which the force decay resembles the well-known inverse-square law typical of van der Waals interactions during the first 0.5–1 nm of decay, a second one in which the force decays almost linearly, in relatively good agreement with capillary force predicted by the constant chemical potential approximation, and a third one in which the attractive force is almost constant, i.e., forms a plateau, up to 3–4 nm above the surface when the formation of a capillary neck dominates the tip–sample interaction.

  1. A flexible piezoelectric force sensor based on PVDF fabrics

    Science.gov (United States)

    Wang, Y. R.; Zheng, J. M.; Ren, G. Y.; Zhang, P. H.; Xu, C.

    2011-04-01

    Polyvinylidene fluoride (PVDF) film has been widely investigated as a sensor and transducer material due to its high piezo-, pyro- and ferroelectric properties. To activate these properties, PVDF films require a mechanical treatment, stretching or poling. In this paper, we report on a force sensor based on PVDF fabrics with excellent flexibility and breathability, to be used as a specific human-related sensor. PVDF nanofibrous fabrics were prepared by using an electrospinning unit and characterized by means of scanning electron microscopy (SEM), FTIR spectroscopy and x-ray diffraction. Preliminary force sensors have been fabricated and demonstrated excellent sensitivity and response to external mechanical forces. This implies that promising applications can be made for sensing garment pressure, blood pressure, heartbeat rate, respiration rate and accidental impact on the human body.

  2. Magnetically controllable Casimir force based on a superparamagnetic metametamaterial

    Science.gov (United States)

    Ma, Junming; Zhao, Qian; Meng, Yonggang

    2014-02-01

    We theoretically investigate the magnetically controllable Casimir force between a parallel metal plate and a superparamagnetic metametamaterial (MMM) plate based on Mie scattering and effective medium theory. A type of MMM composed of superparamagnetic nanoparticles is proposed to fulfill the high frequency magnetic effect to gain Casimir repulsion when interacting with the metal plate. The permeability of such MMM depends on an external magnetic field, which makes it possible to adjust the magnitude of Casimir force. The effects of size, filling ratio, and magnetic property of the superparamagnetic particles on the tuning range are also investigated. Construction of such MMM using the micro/nanofabrication technology is promising to achieve magnetically controllable repulsive Casimir force.

  3. A novel off–on fluorescence chemosensor for Ca{sup 2+} based on Rhodamine–Coumarin Schiff base derivative

    Energy Technology Data Exchange (ETDEWEB)

    An, Jun-mei [College of Chemistry and Chemical Engineering and State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000 (China); Yang, Zheng-yin, E-mail: yangzy@lzu.edu.cn [College of Chemistry and Chemical Engineering and State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000 (China); Yan, Mi-hui; Li, Tian-rong [College of Chemistry and Chemical Engineering and State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000 (China)

    2013-07-15

    A novel sensor, 7-Hydroxy-4-methylcoumarin-8-carbaldehyde-(rhodamine) hydrazone (l) has been synthesized and investigated as a fluorescence chemosensor for Ca{sup 2+} in acetonitrile. The compound is found preferential binding to Ca{sup 2+} in presence of large excess of other competitive ions with associated changes in its optical and fluorescence spectral behavior. Upon the addition of Ca{sup 2+}, an overall emission change of 64-fold was observed. Photoinduced electron transfer (PET) process, coupled with the intramolecular charge transfer (ICT) process, are proposed to explain the observed spectral response. -- Highlights: ► A novel fluorescent sensor based on rhodamine and coumarin has been synthesized to detect Ca{sup 2+}. ► Sensesor shows high sensitivity and selectivity to Ca{sup 2+} with detection limit of 30 ppb.► The sensor can distinguish Ca{sup 2+} and Mg{sup 2+} effectively.

  4. Complex Behavior of Forces Influencing Molten Weld Metal Flow based on Static Force Balance Theory

    Science.gov (United States)

    Achebo, Joseph I.

    This study is aimed at investigating the forces responsible for the detachment of molten metal droplets formed at an electrode tip, which imminently and eventually drop into the weld pool during the welding process. The Equations used by Kim and Eagar in 1993 were applied to this study. It was found that the different detaching forces which are the gravitational force, the electromagnetic force, and the drag force, were determined to be 7.154 x 10-6N, 0.05N and 1.736N respectively. Whereas, the primary retaining force, which is the surface tension force, was calculated to be 0.0195N. From the findings, since the combination of the detaching forces taken together is greater than the retaining force, detachment of the molten metal droplet must inevitably occur. The combined effect of these forces on the behaviour of molten metal during the droplet detachment process was adequately investigated in this study.

  5. Eielson Air Force Base Operable Unit 2 baseline risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, R.E.; Jarvis, T.T.; Jarvis, M.R.; Whelan, G.

    1994-10-01

    Operable Unit 2 at Eielson Air Force Base (AFB) near Fairbanks, is one of several operable units characterized by petroleum, oil, and lubricant contamination, and by the presence of organic products floating at the water table, as a result of Air Force operations since the 1940s. The base is approximately 19,270 acres in size, and comprises the areas for military operations and a residential neighborhood for military dependents. Within Operable Unit 2, there are seven source areas. These source areas were grouped together primarily because of the contaminants released and hence are not necessarily in geographical proximity. Source area ST10 includes a surface water body (Hardfill Lake) next to a fuel spill area. The primary constituents of concern for human health include benzene, toluene, ethylbenzene, and xylenes (BTEX). Monitored data showed these volatile constituents to be present in groundwater wells. The data also showed an elevated level of trace metals in groundwater.

  6. Desulphurization during VIM Refining Ni-base Superalloy using CaO Crucible

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The variation of S content during VIM refining Ni-base superalloy using CaO crucible was stud[ed. It was foundthat the desulphurization process could not be carried out by only using CaO crucible. The role of Al additionto desulphurization was also studied. Combining with the results of XRD and composition analysis of the CaOcrucible, the mechanism of desulphurization was proposed. Thermodynamical calculation about the reaction betweenthe interface of CaO crucible and liquid metal has been discussed. This work indicated that under proper refiningtechnology the S content in the liquid Ni-base alloy could be reduced from 3×10-5 to 2×10-6~4×10-6.

  7. Drainage Canal Survey, Hickam Air Force Base, Hawaii

    Science.gov (United States)

    1993-03-01

    der, The Water Encyclopedia, Second Edition, Chelsea, Michigan, Lewis Publishers, 1990. 4. Manahan , Stanley E., Environmental Chemistry , Fifth...OCCUPATIONAL AND ENVIRONMENTAL HEALTH DIRECTORATE L B2402 E Drive ABrooks Air Force Base, TX 78235P1I14 "• B ELECTEO P 0 •p3193 ER March 1993 A T Final...EDWARD F. MAHER, Col, USAF, BSC Environmental Engineer Consultant Chief, Bioenvironmental Engineering Division Form Approved REPORT DOCUMENTATION PAGE

  8. Wastewater Characterization Survey, Mountain Home Air Force Base, Idaho

    Science.gov (United States)

    1993-03-01

    Water Pollution Control, Second Edition, New York, McGraw-Hill, 1989. 4. Manahan , Stanley E., Environmental Chemistry , Fifth Edition, Chelsea, Michigan...OCCUPATIONAL AND ENVIRONMENTAL HEALTH DIRECTORATE 0 BIOENVIRONMENTAL ENGINEERING DIVISION2402 E Drive Brooks Air Force Base, TX 78235-5114 G March...Royal Road, Springfield VA 22161. DARRIN L. CURTIS, Capt, USAF, BSC EDWARD F. MAHER, Col, USAF, BSC Environmental Engineer Consultant Chief

  9. An EGaIn-based flexible piezoresistive shear and normal force sensor with hysteresis analysis in normal force direction

    Science.gov (United States)

    Shi, Xiaomei; Cheng, Ching-Hsiang; Zheng, Yongping; Wai, P. K. A.

    2016-10-01

    This paper reports a flexible piezoresistive shear and normal force sensor based on eutectic gallium-indium (EGaIn) with fabrication and testing results, which includes further study on the hysteresis analysis in the normal force direction. By using EGaIn as a gauge material, it can detect force on a flexible and stretchable substrate without breaking the gauge wires. However, the liquid-metal gauge wire needs to be packaged and protected in an elastomeric substrate, which creates hysteresis on the sensed resistance with respect to the change of applied force. This paper shows measurement results in static force and also under different speeds of loading force cycles. The relationship between the applied normal force and hysteresis of signal was observed, mainly owing to larger deformation and slower recovering time of the elastomeric substrate that defines the shape of the liquid-metal gauge wire for resistance measurement.

  10. Single fluorescent protein-based Ca2+ sensors with increased dynamic range

    Directory of Open Access Journals (Sweden)

    Labas Yulii A

    2007-06-01

    Full Text Available Abstract Background Genetically encoded sensors developed on the basis of green fluorescent protein (GFP-like proteins are becoming more and more popular instruments for monitoring cellular analytes and enzyme activities in living cells and transgenic organisms. In particular, a number of Ca2+ sensors have been developed, either based on FRET (Fluorescence Resonance Energy Transfer changes between two GFP-mutants or on the change in fluorescence intensity of a single circularly permuted fluorescent protein (cpFP. Results Here we report significant progress on the development of the latter type of Ca2+ sensors. Derived from the knowledge of previously reported cpFP-based sensors, we generated a set of cpFP-based indicators with different spectral properties and fluorescent responses to changes in Ca2+ concentration. Two variants, named Case12 and Case16, were characterized by particular high brightness and superior dynamic range, up to 12-fold and 16.5-fold increase in green fluorescence between Ca2+-free and Ca2+-saturated forms. We demonstrated the high potential of these sensors on various examples, including monitoring of Ca2+ response to a prolonged glutamate treatment in cortical neurons. Conclusion We believe that expanded dynamic range, high brightness and relatively high pH-stability should make Case12 and Case16 popular research tools both in scientific studies and high throughput screening assays.

  11. Cryogel micromechanics unraveled by atomic force microscopy-based nanoindentation.

    Science.gov (United States)

    Welzel, Petra B; Friedrichs, Jens; Grimmer, Milauscha; Vogler, Steffen; Freudenberg, Uwe; Werner, Carsten

    2014-11-01

    Cell-instructive physical characteristics of macroporous scaffolds, developed for tissue engineering applications, often remain difficult to assess. Here, an atomic force microscopy-based nanoindentation approach is adapted to quantify the local mechanical properties of biohybrid glycosaminoglycan-poly(ethylene glycol) cryogels. Resulting from cryoconcentration effects upon gel formation, cryogel struts are observed to feature a higher stiffness compared to the corresponding bulk hydrogel materials. Local Young's moduli, porosity, and integral moduli of the cryogel scaffolds are compared in dependence on gel formation parameters. The results provide valuable insights into the cryogelation process and a base for adjusting physical characteristics of the obtained cryogel scaffolds, which can critically influence the cellular response.

  12. Active contour model based on force field analysis

    Institute of Scientific and Technical Information of China (English)

    HOU Zhi-qiang; HAN Chong-zhao

    2006-01-01

    The traditional snake initial contour should be close to the true boundary of an object of interest in an image;otherwise,an incorrect result will be obtained.Next,active contours have difficulties progressing into boundary concavities.Moreover,the traditional snake as well as almost all of its improved methods can be easily obtained from the local minimum because snake models are nonconvex.An active contour model based on force field analysis (FFA),namely,FFA snake model,is presented in this paper.Based on analyzing force distribution rules of the distance potential force field,a standard is introduced here to distinguish the false one from contour points.The result is not considered as the final solution when the snake energy is minimal.Furthermore,estimation and calculation should be made according to the established standard;only then can the result be considered final.Thus,the snake is prevented from running into the local minimum.The simulation results show that the FFA snake model has a large capture range and can move a snake into the boundary concavities,and that it is able to obtain the object of interest's contour precisely.Compared with the gradient vector flow snake,this new model has a low computational cost.

  13. CaGrid Workflow Toolkit: A taverna based workflow tool for cancer grid

    Directory of Open Access Journals (Sweden)

    Sulakhe Dinanath

    2010-11-01

    Full Text Available Abstract Background In biological and medical domain, the use of web services made the data and computation functionality accessible in a unified manner, which helped automate the data pipeline that was previously performed manually. Workflow technology is widely used in the orchestration of multiple services to facilitate in-silico research. Cancer Biomedical Informatics Grid (caBIG is an information network enabling the sharing of cancer research related resources and caGrid is its underlying service-based computation infrastructure. CaBIG requires that services are composed and orchestrated in a given sequence to realize data pipelines, which are often called scientific workflows. Results CaGrid selected Taverna as its workflow execution system of choice due to its integration with web service technology and support for a wide range of web services, plug-in architecture to cater for easy integration of third party extensions, etc. The caGrid Workflow Toolkit (or the toolkit for short, an extension to the Taverna workflow system, is designed and implemented to ease building and running caGrid workflows. It provides users with support for various phases in using workflows: service discovery, composition and orchestration, data access, and secure service invocation, which have been identified by the caGrid community as challenging in a multi-institutional and cross-discipline domain. Conclusions By extending the Taverna Workbench, caGrid Workflow Toolkit provided a comprehensive solution to compose and coordinate services in caGrid, which would otherwise remain isolated and disconnected from each other. Using it users can access more than 140 services and are offered with a rich set of features including discovery of data and analytical services, query and transfer of data, security protections for service invocations, state management in service interactions, and sharing of workflows, experiences and best practices. The proposed solution is

  14. CaGrid Workflow Toolkit: a Taverna based workflow tool for cancer grid.

    Science.gov (United States)

    Tan, Wei; Madduri, Ravi; Nenadic, Alexandra; Soiland-Reyes, Stian; Sulakhe, Dinanath; Foster, Ian; Goble, Carole A

    2010-11-02

    In biological and medical domain, the use of web services made the data and computation functionality accessible in a unified manner, which helped automate the data pipeline that was previously performed manually. Workflow technology is widely used in the orchestration of multiple services to facilitate in-silico research. Cancer Biomedical Informatics Grid (caBIG) is an information network enabling the sharing of cancer research related resources and caGrid is its underlying service-based computation infrastructure. CaBIG requires that services are composed and orchestrated in a given sequence to realize data pipelines, which are often called scientific workflows. CaGrid selected Taverna as its workflow execution system of choice due to its integration with web service technology and support for a wide range of web services, plug-in architecture to cater for easy integration of third party extensions, etc. The caGrid Workflow Toolkit (or the toolkit for short), an extension to the Taverna workflow system, is designed and implemented to ease building and running caGrid workflows. It provides users with support for various phases in using workflows: service discovery, composition and orchestration, data access, and secure service invocation, which have been identified by the caGrid community as challenging in a multi-institutional and cross-discipline domain. By extending the Taverna Workbench, caGrid Workflow Toolkit provided a comprehensive solution to compose and coordinate services in caGrid, which would otherwise remain isolated and disconnected from each other. Using it users can access more than 140 services and are offered with a rich set of features including discovery of data and analytical services, query and transfer of data, security protections for service invocations, state management in service interactions, and sharing of workflows, experiences and best practices. The proposed solution is general enough to be applicable and reusable within other

  15. Thermodynamic properties and atomic structure of Ca-based liquid alloys

    Science.gov (United States)

    Poizeau, Sophie

    To identify the most promising positive electrodes for Ca-based liquid metal batteries, the thermodynamic properties of diverse Ca-based liquid alloys were investigated. The thermodynamic properties of Ca-Sb alloys were determined by emf measurements. It was found that Sb as positive electrode would provide the highest voltage for Ca-based liquid metal batteries (1 V). The price of such a battery would be competitive for the grid-scale energy storage market. The impact of Pb, a natural impurity of Sb, was predicted successfully and confirmed via electrochemical measurements. It was shown that the impact on the open circuit voltage would be minor. Indeed, the interaction between Ca and Sb was demonstrated to be much stronger than between Ca and Pb using thermodynamic modeling, which explains why the partial thermodynamic properties of Ca would not vary much with the addition of Pb to Sb. However, the usage of the positive electrode would be reduced, which would limit the interest of a Pb-Sb positive electrode. Throughout this work, the molecular interaction volume model (MIVM) was used for the first time for alloys with thermodynamic properties showing strong negative deviation from ideality. This model showed that systems such as Ca-Sb have strong short-range order: Ca is most stable when its first nearest neighbors are Sb. This is consistent with what the more traditional thermodynamic model, the regular association model, would predict. The advantages of the MIVM are the absence of assumption regarding the composition of an associate, and the reduced number of fitting parameters (2 instead of 5). Based on the parameters derived from the thermodynamic modeling using the MIVM, a new potential of mixing for liquid alloys was defined to compare the strength of interaction in different Ca-based alloys. Comparing this trend with the strength of interaction in the solid state of these systems (assessed by the energy of formation of the intermetallics), the systems with

  16. Final Environmental Assessment Nellis Air Force Base School Initiative, Nellis Air Force Base, Clark County, Nevada

    Science.gov (United States)

    2015-04-01

    Environmental Quality CFR Code of Federal Regulations COC Community of Comparison CREDO Center for Research on Education Outcomes (Stanford...Research on Education Outcomes [ CREDO ] 2009). If the new school was not as good as the Lomie Gray Heard School, students living on-base could end up at...Report, CEC- 100-2007-008-CMF. Center for Research on Education Outcomes ( CREDO ) at Stanford University. 2009. Multiple Choice: Charter School

  17. A force plate based method for the calibration of force/torque sensors

    NARCIS (Netherlands)

    Faber, Gert S.; Chang, Chien-Chi; Kingma, Idsart; Schepers, H. Martin; Herber, Sebastiaan; Veltink, Peter H.; Dennerlein, Jack T.

    2012-01-01

    This study describes a novel calibration method for six-degrees-of-freedom force/torque sensors (FTsensors) using a pre-calibrated force plate (FP) as a reference measuring device. In this calibration method, the FTsensor is rigidly connected to a FP and force/torque data are synchronously recorded

  18. Aequorin-Based Luminescence Imaging Reveals Stimulus- and Tissue-Specific Ca2+ Dynamics in Arabidopsis Plants

    Institute of Scientific and Technical Information of China (English)

    Xiaohong Zhu; Ying Feng; Gaimei Liang; Na Liu; Jian-Kang Zhu

    2013-01-01

    Calcium ion is a versatile second messenger for diverse cell signaling in response to developmental and environmental cues.The specificity of Ca2+-mediated signaling is defined by stimulus-elicited Ca2+ signature and down-stream decoding processes.Here,an Aequorin-based luminescence recording system was developed for monitoring Ca2+ in response to various stimuli in Arabidopsis.With the simple,highly sensitive,and robust Ca2+ recording,this system revealed stimulus-and tissue-specific Ca2+ signatures in seedlings.Cellular Ca2+ dynamics and relationship to Aequorin-based Ca2+ recording were explored using a GFP-based Ca2+ indicator,which suggested that a synchronous cellular Ca2+ signal is responsible for cold-induced Ca2+ response in seedlings,whereas asynchronous Ca2+ oscillation contributes to osmotic stress-induced Ca2+ increase in seedlings.The optimized recording system would be a powerful tool for the identification and characterization of novel components in Ca2+-mediated stress-signaling pathways.

  19. Environmental Assessment: General Plan-Based Environmental Impact Analysis Process, Laughlin Air Force Base

    Science.gov (United States)

    2007-05-01

    BASED ENVIROMENTAL IMPACT ANALYSIS PROCESS LAUGHLIN AIR FORCE BASE, TEXAS AGENCY: 47th Flying Training Wing (FTW), Laughlin Air Force Base (AFB), Texas...in their decision-making process. The President’s Council on Environmental Quality (CEQ) has issued regulations to implement NEPA that include...Order (EO) 12898, Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations, was issued by the President on

  20. Research on Robot Surface Tracking Motion Based on Force Control of Six-Axis Wrist Force Sensor

    Directory of Open Access Journals (Sweden)

    Zhijun Wang

    2015-01-01

    Full Text Available In order to reduce the environmental contact force and make the operation task completed successfully, the robot is frequently required with force perception and active compliance control. Based on the six-axis wrist force sensor measuring, a robot model of surface tracking motion is proposed, and its force control algorithm and experiment are studied. The measurement principle of the six-axis wrist force sensor and the inadequacy of the sensor measuring the six-dimensional force online are introduced firstly. The surface tracking motion model and its coordinate system are established. On this basis, the relationship between the pose adjustment of surface tracking motion and the measuring results of the six-axis wrist force sensor is deduced. At last, the experimental study of the surface tracking robot system that applied the force control algorithm is conducted. The experiment shows that the robot can adjust the current position and orientation in real time according to the six-axis wrist force sensor measuring, which demonstrates the feasibility of the surface tracking motion model and the correctness of the force control algorithm.

  1. Microstructures and Mechanical Study of Mg Alloy Foam Based on Mg-Zn-Ca-CaCO3 System

    Science.gov (United States)

    Erryani, A.; Pramuji, F.; Annur, D.; Amal, M. I.; Kartika, I.

    2017-05-01

    Magnesium alloy, a material that has potential to use some applications such as aerospace components, computer parts, and mobile phones. Magnesium alloy can also be a popular candidate as an orthopedic implant material for biodegradability, non-toxicity, and mechanical and physical properties that are excellent. Magnesium, one of the main macro elements required for the proper functioning of the human organism, is used to test the materials for biodegradable implants. The main objective of this study was to find out the microstructure, and mechanical characteristics of the Mg-Ca-Zn-CaCO3 alloy as porous implant materials are biodegradable. The presence of CaCO3 on the alloy functions as a foaming agent expected to produce gas bubbles during manufacturing process taken place that will form pores in the alloy. Mg-Ca-Zn-CaCO3 alloy was made by powder metallurgy method with three variations of composition (96Mg-Ca-3Zn-CaCO3, 91Mg-Ca-3Zn-5CaCO3, and 86Mg-Ca-3Zn-10CaCO3 wt%). Milling process was by using a shaker mill for 2 hours to produce a powder size distribution which was more homogeneous. The mixed powder was uniaxially pressed at a pressure of 100 MPa for 2 minutes and 200 MPa for 3 minutes into green compacts with dimensions of 10 mm in diameter and 10 mm in length. The sintering process was carried out at 650°C with a variation of holding time of 10 and 15 hours, and then the specimens were cooled down at room temperature. Microstructural analysis was performed by using X-Ray diffraction technique and Scanning electron microscopy equipped with an energy disperse spectrometry (EDS). The mechanical characteristics were analyzed by using Universal Testing Machine. The density and porosity of specimen were further measured by using Archimedes method. The results show that the optimum microstructure and mechanical characteristics are the holding time of 10 hours. The value of compression was 208.398 N/mm2, the density was 1.63 g/cc and a porosity was 18% on the

  2. Estimating playa lake flooding: Edwards Air Force Base, California, USA

    Science.gov (United States)

    French, Richard H.; Miller, Julianne J.; Dettling, Charles R.

    2005-05-01

    Playa, or terminal lakes are essentially flat surfaces with minimal topographic relief, and they are common in most semi and arid-environments. Both ground and surface waters can accumulate within a terminal basin and result in flooding of the playa. Within the boundaries of Edwards Air Force Base, located in Southern California, there are four playas: Rosamond, Buckhorn, Rogers, and Rich Dry Lakes. The Rosamond and Rogers playas are currently and have historically been used as runways, taxiways, and industrial areas by the US Air Force and National Aeronautics and Space Administration. A flood assessment of Rogers Dry Lake was mandated due to Air Force regulations concerning delineation of 100-year flood hazard zones, and US Federal regulations, which specify that playas are 100-year special flood hazard zones. From an environmental viewpoint, when water is present, playa lakes can also provide habitat for migratory birds. There is neither guidance nor a generally accepted approach for identifying flood hazards on playas. Therefore, an approach was developed to determine the 100-year regulatory floodplain associated with a dry lakebed, and this approach was used to define tile regulatory floodplain on Rogers and Rich Dry Lakes. This paper describes the application of the method developed to estimate the regulatory 100-year depth of water on Roger and Rich Dry Lakes.

  3. 41Ca ultratrace determination with isotopic selectivity > 10(12) by diode-laser-based RIMS.

    Science.gov (United States)

    Müller, P; Bushaw, B A; Blaum, K; Diel, S; Geppert, C; Nähler, A; Trautmann, N; Nörtershäuser, W; Wendt, K

    2001-07-01

    41Ca ultratrace determination by diode-laser-based resonance ionization mass spectrometry with extremely high isotopic selectivity is presented. Application to environmental dosimetry of nuclear reactor components, to cosmochemical investigations of production cross sections, and biomedical isotope-tracer studies of human calcium kinetics are discussed. Future investigations are possible use in 41Ca-radiodating. Depending on the application, 41Ca isotopic abundances in the range of 10(-9) to 10(-15) relative to the dominant stable isotope 40Ca must be determined. Either double- or triple-resonance optical excitation with narrow-band extended cavity diode lasers and subsequent non-resonant photoionization of calcium in a collimated atomic beam were used. The resulting photoions are detected with a quadrupole mass spectrometer optimized for background reduction and neighboring mass suppression. Applying the full triple-resonance scheme provides a selectivity of approximately 5 x 10(12) in the suppression of neighboring isotopes and > 10(8) for isobars, together with an overall detection efficiency of approximately 5 x 10(-5). Measurements on a variety of sample types are discussed; the accuracy and reproducibility of the resulting 41Ca/40Ca isotope ratios was better than 5%.

  4. STS-49 Lands at Edwards Air Force Base

    Science.gov (United States)

    1992-01-01

    STS-49 Orbiter Endeavour landed at Edwards Air Force Base on May 16, 1992 The drogue chute precedes the main chute in NASA's first exercise of its detailed test objective on the drag chute system. STS-49 ended its successful nine day mission dedicated to the retrieval, repair, and redeployment of the the INTELSAT VI (F-3) satellite. The communication satellite for the International Telecommunication Satellite organization had been stranded in an unusable orbit since its launch aboard the Titan rocket in March 1990. The mission marked the first time 3 astronauts worked simultaneously outside the space craft.

  5. ROBOT'S MOTION ERROR AND ONLINE COMPENSATION BASED ON FORCE SENSOR

    Institute of Scientific and Technical Information of China (English)

    GAN Fangjian; LIU Zhengshi; REN Chuansheng; ZHANG Ping

    2007-01-01

    Robot's dynamic motion error and on-line compensation based on multi-axis force sensor are dealt with. It is revealed that the reasons of the error are formed and the relations of the error are delivered. A motion equation of robot's termination with the error is established, and then, an error matrix and an error compensation matrix of the motion equation are also defined. An on-line error's compensation method is put forward to decrease the displacement error, which is a degree of millimeter, shown by the result of Simulation of PUMA562 robot.

  6. Atomic force microscopy-based characterization and design of biointerfaces

    Science.gov (United States)

    Alsteens, David; Gaub, Hermann E.; Newton, Richard; Pfreundschuh, Moritz; Gerber, Christoph; Müller, Daniel J.

    2017-03-01

    Atomic force microscopy (AFM)-based methods have matured into a powerful nanoscopic platform, enabling the characterization of a wide range of biological and synthetic biointerfaces ranging from tissues, cells, membranes, proteins, nucleic acids and functional materials. Although the unprecedented signal-to-noise ratio of AFM enables the imaging of biological interfaces from the cellular to the molecular scale, AFM-based force spectroscopy allows their mechanical, chemical, conductive or electrostatic, and biological properties to be probed. The combination of AFM-based imaging and spectroscopy structurally maps these properties and allows their 3D manipulation with molecular precision. In this Review, we survey basic and advanced AFM-related approaches and evaluate their unique advantages and limitations in imaging, sensing, parameterizing and designing biointerfaces. It is anticipated that in the next decade these AFM-related techniques will have a profound influence on the way researchers view, characterize and construct biointerfaces, thereby helping to solve and address fundamental challenges that cannot be addressed with other techniques.

  7. Carbon Dioxide Captured from Flue Gas by Modified Ca-based Sorbents in Fixed-bed Reactor at High Temperature

    Institute of Scientific and Technical Information of China (English)

    YANG Lei; YU Hongbing; WANG Shengqiang; WANG Haowen; ZHOU Qibin

    2013-01-01

    Four kinds of Ca-based sorbents were prepared by calcination and hydration reactions using different precursors: calcium hydroxide,calcium carbonate,calcium acetate monohydrate and calcium oxide.The CO2 absorption capacity of those sorbents was investigated in a fixed-bed reactor in the temperature range of 350 650 ℃.It was found that all of those sorbents showed higher capacity for CO2 absorption when the operating temperature higher than 450 ℃.The CaAc2-CaO sorbent showed the highest CO2 absorption capacity of 299 mg·g-1.The morphology of those sorbents was examined by scanning electron microscope(SEM),and the changes of composition before and after carbonation were also determined by X-ray diffraction(XRD).Results indicated that those sorbents have the similar chemical compositions and crystalline phases before carbonation reaction [mainly Ca(OH)2],and CaCO3 is the main component after carbonation reaction.The SEM morphology shows clearly that the sorbent pores were filled with reaction products after carbonation reaction,and became much denser than before.The N2 adsorption-desorption isotherms indicated that the CaAc2-CaO and CaCO3-CaO sorbents have higher specific surface area,larger pore volume and appropriate pore size distribution than that of CaO-CaO and Ca(OH)2-CaO.

  8. 76 FR 75453 - Restricted Areas and Danger Zones at Eglin Air Force Base, FL

    Science.gov (United States)

    2011-12-02

    ... follows: Sec. 334.700 Choctawhatchee Bay, aerial gunnery ranges, Air Armament Center, Eglin Air Force Base... Mexico adjacent to Santa Rosa Island, Headquarters Air Armament Center, Eglin Air Force Base, Fla. (a... Santa Rosa Island, Armament Center, Eglin Air Force Base, Fla. (a) The areas. (1) The danger zone....

  9. Elastic properties of Ca-based metallic glasses predicted by first-principles simulations

    Energy Technology Data Exchange (ETDEWEB)

    Widom, M.; Sauerwine, B.; Cheung, A.M.; Poon, S.J.; Tong, P.; Louca, D.; Shiflet, G.J. (CM); (UV)

    2012-07-11

    First-principles simulations of Ca-based metallic glass-forming alloys yield sample amorphous structures whose structures can be compared to experiment and whose properties can be analyzed. In an effort to understand and control ductility, we investigate the elastic moduli. Calculated Poisson ratios depend strongly on alloying elements in a manner that correlates with ionicity (charge transfer). Consequently, we predict that alloying Ca with Mg and Zn should result in relatively ductile glasses compared to alloying with Ag, Cu, or Al. Experimental observations validate these predictions.

  10. Force-compensated hydrogel-based pH sensor

    Science.gov (United States)

    Deng, Kangfa; Gerlach, Gerald; Guenther, Margarita

    2015-04-01

    This paper presents the design, simulation, assembly and testing of a force-compensated hydrogel-based pH sensor. In the conventional deflection method, a piezoresistive pressure sensor is used as a chemical-mechanical-electronic transducer to measure the volume change of a pH-sensitive hydrogel. In this compensation method, the pH-sensitive hydrogel keeps its volume constant during the whole measuring process, independent of applied pH value. In order to maintain a balanced state, an additional thermal actuator is integrated into the close-loop sensor system with higher precision and faster dynamic response. Poly (N-isopropylacrylamide) (PNIPAAm) with 5 mol% monomer 3-acrylamido propionic acid (AAmPA) is used as the temperature-sensitive hydrogel, while poly (vinyl alcohol) with poly (acrylic acid) (PAA) serves as the pH-sensitive hydrogel. A thermal simulation is introduced to assess the temperature distribution of the whole microsystem, especially the temperature influence on both hydrogels. Following tests are detailed to verify the working functions of a sensor based on pH-sensitive hydrogel and an actuator based on temperature-sensitive hydrogel. A miniaturized prototype is assembled and investigated in deionized water: the response time amounts to about 25 min, just half of that one of a sensor based on the conventional deflection method. The results confirm the applicability of t he compensation method to the hydrogel-based sensors.

  11. Water Resources Investigations at Edwards Air Force Base since 1988

    Science.gov (United States)

    Sneed, Michelle; Nishikawa, Tracy; Martin, Peter

    2006-01-01

    Edwards Air Force Base (EAFB) in southern California (fig. 1) has relied on ground water to meet its water-supply needs. The extraction of ground water has led to two major problems that can directly affect the mission of EAFB: declining water levels (more than 120 ft since the 1920s) and land subsidence, a gradual downward movement of the land surface (more than 4 ft since the late 1920s). As water levels decline, this valuable resource becomes depleted, thus requiring mitigating measures. Land subsidence has caused cracked (fissured) runways and accelerated erosion on Rogers lakebed. In 1988, the U.S. Geological Survey (USGS), in cooperation with the U.S. Air Force, began investigations of the effects of declining water levels and land subsidence at EAFB and possible mitigation measures, such as the injection of imported surface water into the ground-water system. The cooperative investigations included data collection and analyses, numerical simulations of ground-water flow and land subsidence, and development of a preliminary simulation-optimization model. The results of these investigations indicate that the injection of imported water may help to control land subsidence; however, the potential ground-water-quality impacts are unknown.

  12. Improvement of CaO-based sorbent performance for CO{sub 2} looping cycles

    Energy Technology Data Exchange (ETDEWEB)

    Vasilije Manovic; Edward J. Anthony [CANMET Energy Technology Centre-Ottawa, Ottawa, ON (Canada)

    2009-07-01

    This paper presents research on CO{sub 2} capture by lime-based looping cycles. This is a new and promising technology that may help in mitigation of global warming and climate change caused primarily by the use of fossil fuels. The intensity of the anticipated changes urgently requires solutions such as the developing technologies for CO{sub 2} capture, especially those based on CaO looping cycles. This technology is at the pilot plant demonstration stage and there are still significant challenges that require solutions. The technology is based on a dual fluidized bed reactor which contains a carbonator - a unit for CO{sub 2} capture, and a calciner - a unit for CaO regeneration. The major technology components are well known from other technologies and easily applicable. However, even though CaO is a very good candidate as a solid CO{sub 2} carrier, its performance in a practical system still has significant limitations. Thus, research on CaO performance is critical and this paper discusses some of the more important problems and potential solutions that are being examined at CETC-O. To date, the most promising methods were reactivation of spent sorbent by steam, thermal pretreatment of sorbent, and doping, most likely with Al{sub 2}O{sub 3}. The combination of these methods, including pelletization, should provide us with enhanced sorbent performance. 75 refs., 19 figs.

  13. STS-92 - Landing at Edwards Air Force Base

    Science.gov (United States)

    2000-01-01

    The Space Shuttle Discovery glides in for landing at Edwards Air Force Base in Southern California at the conclusion of mission STS-92 on October 24, 2000. STS-92 was the 100th mission since the fleet of four Space Shuttles began flying in 1981. (Due to schedule changes, missions are not always launched in the order that was originally planned.) The almost 13-day mission was the last construction mission for the International Space Station prior to the first scientists taking up residency in the orbiting space laboratory the following month. The seven-member crew on STS-92 included mission specialists Koichi Wakata, Michael Lopez-Alegria, Jeff Wisoff, Bill McArthur and Leroy Chiao, pilot Pam Melroy and mission commander Brian Duffy.

  14. Atomic force microscope based on vertical silicon probes

    Science.gov (United States)

    Walter, Benjamin; Mairiaux, Estelle; Faucher, Marc

    2017-06-01

    A family of silicon micro-sensors for Atomic Force Microscope (AFM) is presented that allows to operate with integrated transducers from medium to high frequencies together with moderate stiffness constants. The sensors are based on Micro-Electro-Mechanical-Systems technology. The vertical design specifically enables a long tip to oscillate perpendicularly to the surface to be imaged. The tip is part of a resonator including quasi-flexural composite beams, and symmetrical transducers that can be used as piezoresistive detector and/or electro-thermal actuator. Two vertical probes (Vprobes) were operated up to 4.3 MHz with stiffness constants 150 N/m to 500 N/m and the capability to oscillate from 10 pm to 90 nm. AFM images of several samples both in amplitude modulation (tapping-mode) and in frequency modulation were obtained.

  15. Based on the Force Deployment Model of Unascertained Expectation

    Directory of Open Access Journals (Sweden)

    Jianli Chen

    2013-05-01

    Full Text Available In this study, we utilize the unascertained mathematics method to give the unascertained number of countermeasure of anti-terrorism strategic force deployment and unknown event. It has been defined the situation sets of force deployment, condition density and mathematical expectation of density model. It has been given the unascertained parameters Cij which decide and direct the force deployment. Find out the condition density matrix of force deployment, further get the conditional density of single target force deployment, using the maximum density mathematical expectation in order to get the optimal mathematical model of multiple target force deployment. Analyzing the coefficient of model and provide two kinds of discussed computing method. The model overcomes the limitation of past deterministic thinking method which study the force deployment and provide the decision maker a relative substantial theory evidence.

  16. FRET-Based Nanobiosensors for Imaging Intracellular Ca2+ and H+ Microdomains

    Directory of Open Access Journals (Sweden)

    Alsu I. Zamaleeva

    2015-09-01

    Full Text Available Semiconductor nanocrystals (NCs or quantum dots (QDs are luminous point emitters increasingly being used to tag and track biomolecules in biological/biomedical imaging. However, their intracellular use as highlighters of single-molecule localization and nanobiosensors reporting ion microdomains changes has remained a major challenge. Here, we report the design, generation and validation of FRET-based nanobiosensors for detection of intracellular Ca2+ and H+ transients. Our sensors combine a commercially available CANdot®565QD as an energy donor with, as an acceptor, our custom-synthesized red-emitting Ca2+ or H+ probes. These ‘Rubies’ are based on an extended rhodamine as a fluorophore and a phenol or BAPTA (1,2-bis(o-aminophenoxyethane-N,N,N′,N′-tetra-acetic acid for H+ or Ca2+ sensing, respectively, and additionally bear a linker arm for conjugation. QDs were stably functionalized using the same SH/maleimide crosslink chemistry for all desired reactants. Mixing ion sensor and cell-penetrating peptides (that facilitate cytoplasmic delivery at the desired stoichiometric ratio produced controlled multi-conjugated assemblies. Multiple acceptors on the same central donor allow up-concentrating the ion sensor on the QD surface to concentrations higher than those that could be achieved in free solution, increasing FRET efficiency and improving the signal. We validate these nanosensors for the detection of intracellular Ca2+ and pH transients using live-cell fluorescence imaging.

  17. Role of hydrogen in the electronic properties of CaFeAsH-based superconductors

    Science.gov (United States)

    Huang, Y. N.; Liu, D. Y.; Zou, L. J.; Pickett, W. E.

    2016-05-01

    The electronic and magnetic properties of the hydride superconductor CaFeAsH, which superconducts up to 47 K when electron doped with La, and the isovalent alloy system CaFeAsH1 -xFx are investigated using density functional based methods. The Q ⃗=(π ,π ,0 ) peak of the nesting function ξ (q ⃗) is found to be extremely strong and sharp, and the additional structure in ξ (q ⃗) associated with the near-circular Fermi surfaces (FSs) that may impact low energy excitations is quantified. The unusual band introduced by H, which shows strong dispersion perpendicular to the FeAs layers, is shown to be connected to a peculiar van Hove singularity just below the Fermi level. This band provides a three-dimensional electron ellipsoid Fermi surface not present in other Fe-based superconducting materials nor in CaFeAsF. Electron doping by 25% La or Co has a minor effect on this ellipsoid Fermi surface, but suppresses FS nesting strongly, consistent with the viewpoint that eliminating strong nesting and the associated magnetic order allows high Tc superconductivity to emerge. Various aspects of the isovalent alloy system CaFeAsH1 -xFx and means of electron doping are discussed in terms of influence of incipient bands.

  18. Sitewide feasibility study Eielson Air Force Base, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Last, G.V.; Lanigan, D.C.; Josephson, G.B.; Bagaasen, L.M.

    1995-09-01

    The Sitewide Feasibility Study (FS) is required under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), the National Contingency Plan (NCP), and the Federal Facility Agreement (FFA) for Eielson Air Force Base (AFB). It is based on findings presented in the Sitewide Remedial Investigation (RI) Report (USAF 1995a), and the Sitewide Baseline Risk Assessment (BLRA) Report (USAF 1995b). Under the FFA, 64 potential source areas were placed in one of six operable units, based on similar contaminant and environmental characteristics, or were included for evaluation under a Source Evaluation Report (SER). The sitewide RI was directed at contamination that was not confined to an operable unit (OU) or SER source area. The objectives of the sitewide RI were to: Provide information about site characteristics to support individual OU RI/FS efforts and the sitewide RI/FS, including site hydrogeology and determination of background soil and groundwater characteristics; identify and characterize contamination that is not confined or attributable to a specific source area through sitewide monitoring of groundwater and surface water; evaluate cumulative risks to human health and the environment from contamination on a sitewide basis; and provide a mechanism for continued cohesive sitewide monitoring.

  19. Computerized Integrated Inventory Control for an Air Force Base-Level Supply System.

    Science.gov (United States)

    1980-06-01

    Monterey, California 93940 5. Major Angelo C. Molato 1 Philippine Air Force (Student) No. 62 Medicion I Imus, Cavite Philippines 6. Air Force Computer Center 1 HPAF, Nichols Air Base Pasay City Philippines 136

  20. Preparation and Supercooling Modification of Salt Hydrate Phase Change Materials Based on CaCl₂·2H₂O/CaCl₂.

    Science.gov (United States)

    Xu, Xiaoxiao; Dong, Zhijun; Memon, Shazim Ali; Bao, Xiaohua; Cui, Hongzhi

    2017-06-23

    Salt hydrates have issues of supercooling when they are utilized as phase change materials (PCMs). In this research, a new method was adopted to prepare a salt hydrate PCM (based on a mixture of calcium chloride dihydrate and calcium chloride anhydrous) as a novel PCM system to reduce the supercooling phenomenon existing in CaCl₂·6H₂O. Six samples with different compositions of CaCl₂ were prepared. The relationship between the performance and the proportion of calcium chloride dihydrate (CaCl₂·2H₂O) and calcium chloride anhydrous (CaCl₂) was also investigated. The supercooling degree of the final PCM reduced with the increase in volume of CaCl₂·2H₂O during its preparation. The PCM obtained with 66.21 wt % CaCl₂·2H₂O reduced the supercooling degree by about 96.8%. All six samples, whose ratio of CaCl₂·2H₂O to (CaCl₂ plus CaCl₂·2H₂O) was 0%, 34.03%, 53.82%, 76.56%, 90.74%, and 100% respectively, showed relatively higher enthalpy (greater than 155.29 J/g), and have the possibility to be applied in buildings for thermal energy storage purposes. Hence, CaCl₂·2H₂O plays an important role in reducing supercooling and it can be helpful in adjusting the solidification enthalpy. Thereafter, the influence of adding different percentages of Nano-SiO₂ (0.1 wt %, 0.3 wt %, 0.5 wt %) in reducing the supercooling degree of some PCM samples was investigated. The test results showed that the supercooling of the salt hydrate PCM in Samples 6 and 5 reduced to 0.2 °C and 0.4 °C respectively. Finally, the effect of the different cooling conditions, including frozen storage (-20 °C) and cold storage (5 °C), that were used to prepare the salt hydrate PCM was considered. It was found that both cooling conditions are effective in reducing the supercooling degree of the salt hydrate PCM. With the synergistic action of the two materials, the performance and properties of the newly developed PCM systems were better especially in terms of reducing

  1. 33 CFR 165.1102 - Security Zone; Naval Base Point Loma; San Diego Bay, San Diego, CA.

    Science.gov (United States)

    2010-07-01

    ... Loma; San Diego Bay, San Diego, CA. 165.1102 Section 165.1102 Navigation and Navigable Waters COAST... Guard District § 165.1102 Security Zone; Naval Base Point Loma; San Diego Bay, San Diego, CA. (a) Location. The following area is a security zone: The water adjacent to the Naval Base Point Loma, San Diego...

  2. Impact of thermal frequency drift on highest precision force microscopy using quartz-based force sensors at low temperatures

    Directory of Open Access Journals (Sweden)

    Florian Pielmeier

    2014-04-01

    Full Text Available In frequency modulation atomic force microscopy (FM-AFM the stability of the eigenfrequency of the force sensor is of key importance for highest precision force measurements. Here, we study the influence of temperature changes on the resonance frequency of force sensors made of quartz, in a temperature range from 4.8–48 K. The sensors are based on the qPlus and length extensional principle. The frequency variation with temperature T for all sensors is negative up to 30 K and on the order of 1 ppm/K, up to 13 K, where a distinct kink appears, it is linear. Furthermore, we characterize a new type of miniaturized qPlus sensor and confirm the theoretically predicted reduction in detector noise.

  3. "Galileo's Machine": Late Notes on Free Fall, Projectile Motion, and the Force of Percussion (ca. 1638-1639)

    Science.gov (United States)

    Salvia, Stefano

    2014-12-01

    My paper focuses upon the problem of determining the nature, establishing the proportionality, and measuring the intensity of the force of percussion of a projected or falling body, as treated in the Sixth Day of Galileo's Discorsi e dimostrazioni matematiche intorno a due nuove scienze (1638). This fragment was written around 1638-1639 as part of two additional Days of the Discorsi, which Galileo never finished and remained unpublished until 1718. Galileo's last works on percussion show a significant step towards a generalization of his own views on uniform and accelerated motion that will later lead to the Newtonian principle of inertia. The experiment with two equal weights hanging on a pulley, performed in Arcetri during the same period, is compared with the Paduan 1604-1608 experience of the "water balance." Both account for more than three decades of inquiries into what Galileo called forza della percossa, which marked the transition from preclassical to classical mechanics.

  4. Environmental Impact Analysis Process. Environmental Assessment Air Force Small Launch Vehicle, Vandenberg Air Force Base, Edwards Air Force Base, and San Nicolas Island, CA

    Science.gov (United States)

    1991-05-01

    in California. Others are found at Crescent City, Humboldt, Fort Bragg, Point Reyes and Fort Ord. Although all coastal habitats are becoming rare...in riparian woodlands on VAFB (USAF, 1976d). Red-legged frog (Rana aurora ) and Southwestern pond turtle are known to frequent freshwater wetlands

  5. Molecular force spectroscopy with a DNA origami-based nanoscopic force clamp.

    Science.gov (United States)

    Nickels, Philipp C; Wünsch, Bettina; Holzmeister, Phil; Bae, Wooli; Kneer, Luisa M; Grohmann, Dina; Tinnefeld, Philip; Liedl, Tim

    2016-10-21

    Forces in biological systems are typically investigated at the single-molecule level with atomic force microscopy or optical and magnetic tweezers, but these techniques suffer from limited data throughput and their requirement for a physical connection to the macroscopic world. We introduce a self-assembled nanoscopic force clamp built from DNA that operates autonomously and allows massive parallelization. Single-stranded DNA sections of an origami structure acted as entropic springs and exerted controlled tension in the low piconewton range on a molecular system, whose conformational transitions were monitored by single-molecule Förster resonance energy transfer. We used the conformer switching of a Holliday junction as a benchmark and studied the TATA-binding protein-induced bending of a DNA duplex under tension. The observed suppression of bending above 10 piconewtons provides further evidence of mechanosensitivity in gene regulation.

  6. Heat recovery from a thermal energy storage based on the Ca(OH){sub 2}/CaO cycle

    Energy Technology Data Exchange (ETDEWEB)

    Azpiazu, M.N. [E.T.S. Ingenieros, Bilbao (Spain). Dpto. de Ingenieria Quimica y del Medio Ambiente; Morquillas, J.M. [E.T.S. Ingenieros, Bilbao (Spain). Dpto. de Maquinas y Motores Termicos; Vazquez, A. [E.S. da Marina Civil, La Coruna (Spain). Dpto. de Energia y Propulsion Maritima

    2003-04-01

    Thermal energy storage is very important in many applications related to the use of waste heat from industrial processes, renewable energies or from other sources. Thermochemical storage is very interesting for long-term storage as it can be carried out at room temperature with no energy losses. Dehydration/hydration cycle of Ca(OH){sub 2}/CaO has been applied for thermal energy storage in two types of reactors. One of them was a prototype designed by the authors, and in the other type conventional laboratory glassware was used. Parameters such as specific heats, reaction rate and enthalpy, mass losses and heat release were monitored during cycles. Although in the hydration step water is normally added in vapour phase, liquid water, at 0{sup o}C has been used in these experiences. Results indicated that the energy storage system performance showed no significant differences, when we compared several hydration/dehydration cycles. The selected chemical reaction did not exhibit a complete reversibility because complete Ca(OH){sub 2} dehydration, was not achieved. However the system could be used satisfactorily along 20 cycles at least. Heat recovery experiments showed general system behaviour during the hydration step in both types of reactors. The designed prototype was more efficient in this step. Main conclusions suggested carrying out one complete cycle at a higher dehydration temperature to recover total system reversibility. A modification of the prototype design trying to enhance heat transfer from the Ca(OH){sub 2} bed could also be proposed. (author)

  7. Chelate titrations of Ca(2+) and Mg(2+) using microfluidic paper-based analytical devices.

    Science.gov (United States)

    Karita, Shingo; Kaneta, Takashi

    2016-06-14

    We developed microfluidic paper-based analytical devices (μPADs) for the chelate titrations of Ca(2+) and Mg(2+) in natural water. The μPAD consisted of ten reaction zones and ten detection zones connected through narrow channels to a sample zone located at the center. Buffer solutions with a pH of 10 or 13 were applied to all surfaces of the channels and zones. Different amounts of ethylenediaminetetraacetic acid (EDTA) were added to the reaction zones and a consistent amount of a metal indicator (Eriochrome Black T or Calcon) was added to the detection zones. The total concentrations of Ca(2+) and Mg(2+) (total hardness) in the water were measured using a μPAD containing a buffer solution with a pH of 10, whereas only Ca(2+) was titrated using a μPAD prepared with a potassium hydroxide solution with a pH of 13. The μPADs permitted the determination of Ca(2+) and Mg(2+) in mineral water, river water, and seawater samples within only a few minutes using only the naked eye-no need of instruments.

  8. Improve photovoltaic performance of titanium dioxide nanorods based dye-sensitized solar cells by Ca-doping

    Energy Technology Data Exchange (ETDEWEB)

    Li, Weixin; Yang, Junyou, E-mail: jyyang@mail.hust.edu.cn; Zhang, Jiaqi; Gao, Sheng; Luo, Yubo; Liu, Ming

    2014-09-15

    Highlights: • TiO{sub 2} nanorods doped with Ca ions were synthesized by one-step hydrothermal method. • The flat band edge of rutile TiO{sub 2} shifted positively via Ca-doping. • The photoelectric conversion efficiency of dye-sensitized solar cells (DSSCs) based on TiO{sub 2} electrode was much enhanced by Ca-doping. • A relatively high open circuit voltage was obtained by adopting Ca-doped TiO{sub 2} nanorods electrode. - Abstract: Ca-doped TiO{sub 2} nanorod arrays were prepared via the one-step hydrothermal method successfully, and the effect of Ca ions content on the photovoltaic conversion efficiency of dye-sensitized solar cells has been fully discussed in the paper. Although no obvious change on the microstructure and morphology was observed by field emission scanning electron microscope and transmission electron microscope for the Ca-doped samples, the results of X-ray diffraction and X-ray photoelectron spectroscopy confirmed that Ti{sup 4+} was substituted with Ca{sup 2+} successfully. UV–vis spectroscopy results revealed that the flat band edge shifted positively by Ca ions doping. The photovoltaic conversion efficiency of the dye-sensitized solar cells based on the 2 mol% Ca-doped TiO{sub 2} electrode was 43% higher than that of the undoped one due to the less recombination possibility.

  9. Microstructure and tensile properties of magnesium alloy modified by Si/Ca based refiner

    Institute of Scientific and Technical Information of China (English)

    DUAN Zhi-chao; SUN Yang-shan; WEI Yu; DU Wen-wen; XUE Feng; ZHU Tian-bai

    2005-01-01

    Microstructure and mechanical properties of pure magnesium and AZ31 alloy with Ca/Si based refiner addition were investigated. The results indicate that addition of Ca/Si based refiners to pure magnesium and AZ31 alloy results in remarkable microstructure refinement. With proper amount of refiner addition, the grain size in as cast ingots can be one order of magnitude lower than that without refiner addition. Small amount of refiner addition to AZ31 alloy increases both ultimate strength and yield strength significantly, while the ductility of the alloy with refiner addition is similar to that without refiner addition. Addition of refiner improves the deformability of AZ31 alloy and extruded or hot rolled specimens (rods or sheets) with refiner addition exhibit higher surface quality and mechanical properties than those without refiner addition.

  10. Final Environmental Assessment: Replacement Joint Force Headquarters Building, Hanscom Air Force Base Massachusetts

    Science.gov (United States)

    2010-01-22

    occupies building 1503 with the State Medical Command (Med Com). Med Com plans, programs, provides, and sustains health force protection and medical/ dental ...Center for Health Promotion and Preventative Medicine (USACHPPM) Dempsey, Judith; Polyak , Lisa; Tushek, Stephen. Technical Guide for Preparing a... Polyak , Lisa; Tushek, Stephen. Technical Guide for Preparing a Record of Nonapplicability for the General Conformity Rule. November 2003. USEPA. AP 42

  11. Removal of mercury from flue gas using Ca-based sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Ren, J.L.; Luo, Y.Y.; Xu, Z.; Zhong, Y.J. [Zhejiang Univ. of Technology, Hangzhou (China). MOE Key Laboratory of Mechanical Manufacture and Automation; Zhou, J.S. [Zhejiang Univ., Hangzhou, (China). Inst. of Thermal Power Engineering, State Key Laboratory of Clean Energy Utilization

    2008-07-01

    Mercury (Hg) emissions from power plants raise environmental concerns, particularly in China's coal-fired power plants. Mercury is present mainly in the vapor form (Hg0) and cannot be captured effectively by existing particulate removal systems because of its high volatility and insolubility in water. It is therefore necessary to design and manufacture more cost-effective mercury sorbents to replace conventional sorbents already in use for mercury control. This paper reported on a study in which the characteristics of mercury sorption by 3 kinds of calcium (Ca)based sorbents were studied, notably lime, hydrated lime and a mixture of fly ash and hydrated lime (MFC). Adsorption experiments were performed in a bench-scale fixed-bed mercury sorption facility with a mercury permeation tube embedded in an isothermal water bath and simulated flue gas compositions. The effects of sulphur dioxide (SO{sub 2}) on adsorption were investigated along with the adsorption mechanism. The study showed that the performance of Ca-based sorbents was better in the presence of SO{sub 2} than the baseline conditions. In the absence SO{sub 2}, the Hg0 adsorption effectiveness of the 3 kinds of Ca-based sorbents was lower. In the presence of SO{sub 2}, adsorption efficiency improved by 15 to 20 per cent and the adsorption capacity was more than 50 per cent at 30 minutes of exposure of sorbents to the flue gas. Higher temperature was found to be beneficial to the adsorption process. SO{sub 2} reacted with the Ca-based sorbents and produced active adsorption sites on the surface of the sorbents, thus oxidating Hg0 to Hg2+ and improving capture efficiency by chemisorption. 14 refs., 2 tabs., 8 figs.

  12. Virtual force field based obstacle avoidance and agent based intelligent mobile robot

    Science.gov (United States)

    Sarkar, Saurabh; Reynolds, Scott; Hall, Ernest

    2007-09-01

    This paper presents a modified virtual force based obstacle avoidance approach suited for laser range finder. The modified method takes advantage of the polar coordinate based data sent by the laser sensor by mapping the environment in a polar coordinate system. The method also utilizes a Gaussian function based certainty values to detect obstacle. The method successfully navigates through complex obstacles and reaches target GPS waypoints.

  13. Determination of electrostatic force and its characteristics based on phase difference by amplitude modulation atomic force microscopy

    Science.gov (United States)

    Wang, Kesheng; Cheng, Jia; Yao, Shiji; Lu, Yijia; Ji, Linhong; Xu, Dengfeng

    2016-12-01

    Electrostatic force measurement at the micro/nano scale is of great significance in science and engineering. In this paper, a reasonable way of applying voltage is put forward by taking an electrostatic chuck in a real integrated circuit manufacturing process as a sample, applying voltage in the probe and the sample electrode, respectively, and comparing the measurement effect of the probe oscillation phase difference by amplitude modulation atomic force microscopy. Based on the phase difference obtained from the experiment, the quantitative dependence of the absolute magnitude of the electrostatic force on the tip-sample distance and applied voltage is established by means of theoretical analysis and numerical simulation. The results show that the varying characteristics of the electrostatic force with the distance and voltage at the micro/nano scale are similar to those at the macroscopic scale. Electrostatic force gradually decays with increasing distance. Electrostatic force is basically proportional to the square of applied voltage. Meanwhile, the applicable conditions of the above laws are discussed. In addition, a comparison of the results in this paper with the results of the energy dissipation method shows the two are consistent in general. The error decreases with increasing distance, and the effect of voltage on the error is small.

  14. Endosome-based protein trafficking and Ca2+ homeostasis in the heart

    Science.gov (United States)

    Curran, Jerry; Makara, Michael A.; Mohler, Peter J.

    2015-01-01

    The ability to dynamically regulate, traffic, retain, and recycle proteins within the cell membrane is fundamental to life and central to the normal function of the heart. In the cardiomyocyte, these pathways are essential for the regulation of Ca2+, both at the level of the plasma membrane, but also in local cellular domains. One intracellular pathway often overlooked in relation to cardiovascular Ca2+ regulation and signaling is the endosome-based trafficking pathway. Highlighting its importance, this system and its molecular components are evolutionarily conserved across all metazoans. However, remarkably little is known of how endosome-based protein trafficking and recycling functions within mammalian cells systems, especially in the heart. As the endosomal system acts to regulate the expression and localization of membrane proteins central for cardiac Ca2+ regulation, understanding the in vivo function of this system in the heart is critical. This review will focus on endosome-based protein trafficking in the heart in both health and disease with special emphasis for the role of endocytic regulatory proteins, C-terminal Eps15 homology domain-containing proteins (EHDs). PMID:25709583

  15. Dissolution Behavior of Alumina-Based Inclusions in CaF2-Al2O3-CaO-MgO-SiO2 Slag Used for the Electroslag Metallurgy Process

    Directory of Open Access Journals (Sweden)

    Yanwu Dong

    2016-11-01

    Full Text Available Removal of non-metallic inclusions to CaF2-based slag is one of the most important functions of electroslag remelting. In this work, the dissolution behavior for alumina-based inclusions in CaF2-Al2O3-CaO-MgO-SiO2 slag has been investigated. Results indicate that the diffusion or permeability capacity of slag components into alumina particles is F−, Ca2+, Si4+, Mg2+, from strongest to weakest, for CaF2-Al2O3-CaO-MgO-SiO2 slag. Alumina inclusions react with F− in liquid slag at first and then react with CaO to form xCaO-yAl2O3 system. Subsequently, MgO substitutes for CaO to form a MgO-Al2O3 system layer surrounding the other product and reactant, and then enters the liquid slag. CaF2 can improve the dissolution capacity of slag to alumina inclusions. A complex region was formed between alumina-based particles and the slag, with different areas dominated by CaF2, CaO-Al2O3, CaO-SiO2 and MgO-Al2O3. The dissolution process of alumina particles in slag is different from the formation of compound inclusions originated from the Al-O deoxidization reaction.

  16. Problem-Based Learning in 9th Grade Chemistry Class: "Intermolecular Forces"

    Science.gov (United States)

    Tarhan, Leman; Ayar-Kayali, Hulya; Urek, Raziye Ozturk; Acar, Burcin

    2008-01-01

    This research study aims to examine the effectiveness of a problem-based learning (PBL) on 9th grade students' understanding of intermolecular forces (dipole-dipole forces, London dispersion forces and hydrogen bonding). The student's alternate conceptions about intermolecular bonding and their beliefs about PBL were also measured. Seventy-eight…

  17. Development of Tuning Fork Based Probes for Atomic Force Microscopy

    Science.gov (United States)

    Jalilian, Romaneh; Yazdanpanah, Mehdi M.; Torrez, Neil; Alizadeh, Amirali; Askari, Davood

    2014-03-01

    This article reports on the development of tuning fork-based AFM/STM probes in NaugaNeedles LLC for use in atomic force microscopy. These probes can be mounted on different carriers per customers' request. (e.g., RHK carrier, Omicron carrier, and tuning fork on a Sapphire disk). We are able to design and engineer tuning forks on any type of carrier used in the market. We can attach three types of tips on the edge of a tuning fork prong (i.e., growing Ag2Ga nanoneedles at any arbitrary angle, cantilever of AFM tip, and tungsten wire) with lengths from 100-500 μm. The nanoneedle is located vertical to the fork. Using a suitable insulation and metallic coating, we can make QPlus sensors that can detect tunneling current during the AFM scan. To make Qplus sensors, the entire quartz fork will be coated with an insulating material, before attaching the nanoneedle. Then, the top edge of one prong is coated with a thin layer of conductive metal and the nanoneedle is attached to the fork end of the metal coated prong. The metal coating provides electrical connection to the tip for tunneling current readout and to the electrodes and used to read the QPlus current. Since the amount of mass added to the fork is minimal, the resonance frequency spectrum does not change and still remains around 32.6 KHz and the Q factor is around 1,200 in ambient condition. These probes can enhance the performance of tuning fork based atomic microscopy.

  18. Final Environmental Assessment: To Relocate Air Force Explosive Ordnance Disposal Administrative Complex at Eglin Air Force Base

    Science.gov (United States)

    2006-10-01

    Trips PM10E = .0022 * Trips COE = .262 * Trips Year 2010 and beyond: VOCE = .012 * Trips NOxE = .013 * Trips PM10E = .0022 * Trips COE...Air Force Base, Florida To convert from pounds per day to tons per year: VOC (tons/yr) = VOCE * DPYII/2000 NOx (tons/yr) = NOxE * DPYII/2000

  19. Environmental Assessment for Construction of Security Forces Training Facilities and Force Protection Upgrades at Schriever Air Force Base, Colorado

    Science.gov (United States)

    2003-01-01

    former ranches (CNHP, 2000). Isolated populations of the noxious weeds Canada thistle (Cirsium arvense) and musk thistle (Carduus nutans) are...resulted in the identification of four jurisdictional wetlands out of nine on-Base sites examined. Based on the re-examination of these nine sites

  20. Do Ca2+-adsorbing ceramics reduce the release of calcium ions from gypsum-based biomaterials?

    Science.gov (United States)

    Belcarz, Anna; Zalewska, Justyna; Pałka, Krzysztof; Hajnos, Mieczysław; Ginalska, Grazyna

    2015-02-01

    Bone implantable materials based on calcium sulfate dihydrate dissolve quickly in tissue liquids and release calcium ions at very high levels. This phenomenon induces temporary toxicity for osteoblasts, may cause local inflammation and delay the healing process. Reduction in the calcium ion release rate by gypsum could be therefore beneficial for the healing of gypsum-filled bone defects. The aim of this study concerned the potential use of calcium phosphate ceramics of various porosities for the reduction of high Ca(2+) ion release from gypsum-based materials. Highly porous ceramics failed to reduce the level of Ca(2+) ions released to the medium in a continuous flow system. However, it succeeded to shorten the period of high calcium level. It was not the phase composition but the high porosity of ceramics that was found crucial for both the shortening of the Ca(2+) release-related toxicity period and intensification of apatite deposition on the composite. Nonporous ceramics was completely ineffective for this purpose and did not show any ability to absorb calcium ions at a significant level. Moreover, according to our observations, complex studies imitating in vivo systems, rather than standard tests, are essential for the proper evaluation of implantable biomaterials.

  1. Effects of trichloroethylene and perchloroethylene on wild rodents at Edwards Air Force Base, California, USA.

    Science.gov (United States)

    Spring, Sarah E; Miles, A Keith; Anderson, Michael J

    2004-09-01

    Effects of inhalation of volatilized trichloroethylene (TCE) or perchloroethylene (PCE) were assessed based on the health and population size of wild, burrowing mammals at Edwards Air Force Base (CA, USA). Organic soil-vapor concentrations were measured at three sites with aquifer contamination of TCE or PCE of 5.5 to 77 mg/L and at two uncontaminated reference sites. Population estimates of kangaroo rats (Dipodomys merriami and D. panamintinus) as well as hematology, blood chemistry, and histopathology of kangaroo rats and deer mice (Peromyscus maniculatus) were compared between contaminated and uncontaminated populations. Maximum soil-gas concentrations associated with groundwater contamination were less than 1.5 microl/L of TCE and 0.07 microl/L of PCE. Population estimates of kangaroo rats were similar at contaminated and reference sites. Hematology, blood chemistry, and histopathology of kangaroo rats and deer mice indicated no evidence of health effects caused by exposure. Trichloroethylene or PCE in groundwater and in related soil gas did not appear to reduce the size of small mammal populations or impair the health of individuals.

  2. A Thermodynamic Model for Predicting Phosphorus Partition between CaO-based Slags and Hot Metal during Hot Metal Dephosphorization Pretreatment Process Based on the Ion and Molecule Coexistence Theory

    Science.gov (United States)

    Yang, Xue-min; Li, Jin-yan; Chai, Guo-ming; Duan, Dong-ping; Zhang, Jian

    2016-08-01

    dephosphorization ability of the CaO-based slags. Furthermore, a parabolic relationship of L P against binary basicity or complex basicity CB2 and CB3 can be established at binary basicity in 1.8 or at complex basicity CB2 and CB3 in 2.0 corresponding to the maximum of dephosphorization ability of the CaO-based slags. However, the linear relationship between L P and optical basicity can only be correlated with the mathematically regressed Λ_{{FeO}} = 1.0 and Λ_{{{{Fe}}_{ 2} {{O}}_{ 3}}} =0.75. A great gradient of oxygen potential or oxygen activity a %,O between the dynamically formed metal film beneath slag-metal interface and hot metal bath is the main driving forces of hot metal dephosphorization by the CaO-based slags. The formed metal film with high oxygen content and low carbon content can dynamically be exchanged or replaced by hot metal elements from bath during hot metal dephosphorization process until dephosphorization products mainly as 3CaO·P2O5 are saturated in the CaO-based slags.

  3. Study on Formation Mechanism of CaO-SiO2-Based Inclusions in Saw Wire Steel

    Science.gov (United States)

    Wang, Kun-Peng; Jiang, Min; Wang, Xin-Hua; Wang, Ying; Zhao, Hao-Qian; Cao, Zhan-Min

    2017-08-01

    Attempts were made to elucidate the formation mechanism of CaO-SiO2-based inclusions in saw wires by both laboratory experiments and industrial trials. The key point was to make clear the origin of CaO in such oxide inclusions. Probable origins of [Ca] in steel were first discussed, which can be taken into steel from the steel-slag reaction or ferrous alloy. As a result, slag-steel chemical reaction equilibrium was carefully evaluated at 1873 K (1600 °C) to classify the changes of dissolved aluminum ([Al]), total magnesium (Mg), and total calcium (Ca) in steel and the caused composition variations of inclusions. With the rise of slag basicity from 0.5 to 1.8, [Al] was remarkably increased from 0.00045 to 0.00139 mass pct, whereas Mg varied in the range of 0.00038 to 0.00048 mass pct. By contrast, Ca was constantly kept below 0.00003 mass pct. Accordingly, Al2O3 and MgO in inclusions witnessed obvious rises from 5 to 23 mass pct and from 2 to 8 mass pct, respectively. By contrast, inclusions were free of CaO when slag basicity was below 1.5. With slag basicity further increased to 1.8, CaO witnessed a negligible rise to only 1.0 mass pct on average. This phenomenon agreed well with thermodynamic calculations, which revealed that chemical reaction between steel and CaO in slag (for example, between [Si] and CaO) was weak to hardly supplying sufficient [Ca] to steel to increase CaO in inclusions. Ca contained in ferrous alloys as contaminations was not the cause of CaO-SiO2-based inclusions, either. The industrial trial results indicated that CaO-SiO2-based inclusions have been readily produced in short time just after BOF tapping. Also, a percentage of them changed slightly with the proceeding of refining. Based on the good agreement of laboratory, industrial, and thermodynamics calculations results, it can be reasonably concluded that CaO-SiO2-based inclusions in saw wire were exogenous particles from entrapped/emulsified top slag, but not products of slag

  4. Chiral EFT based nuclear forces: Achievements and challenges

    CERN Document Server

    Machleidt, R

    2016-01-01

    During the past two decades, chiral effective field theory has become a popular tool to derive nuclear forces from first principles. Two-nucleon interactions have been worked out up to sixth order of chiral perturbation theory and three-nucleon forces up to fifth order. Applications of some of these forces have been conducted in nuclear few- and many-body systems---with a certain degree of success. But in spite of these achievements, we are still faced with great challenges. Among them is the issue of a proper uncertainty quantification of predictions obtained when applying these forces in {\\it ab initio} calculations of nuclear structure and reactions. A related problem is the order by order convergence of the chiral expansion. We start this review with a pedagogical introduction and then present the current status of the field of chiral nuclear forces. This is followed by a discussion of representative examples for the application of chiral two- and three-body forces in the nuclear many-body system includin...

  5. Optimal tracking of a sEMG based force model for a prosthetic hand.

    Science.gov (United States)

    Potluri, Chandrasekhar; Anugolu, Madhavi; Yihun, Yimesker; Jensen, Alex; Chiu, Steve; Schoen, Marco P; Naidu, D Subbaram

    2011-01-01

    This paper presents a surface electromyographic (sEMG)-based, optimal control strategy for a prosthetic hand. System Identification (SI) is used to obtain the dynamic relation between the sEMG and the corresponding skeletal muscle force. The input sEMG signal is preprocessed using a Half-Gaussian filter and fed to a fusion-based Multiple Input Single Output (MISO) skeletal muscle force model. This MISO system model provides the estimated finger forces to be produced as input to the prosthetic hand. Optimal tracking method has been applied to track the estimated force profile of the Fusion based sEMG-force model. The simulation results show good agreement between reference force profile and the actual force.

  6. Soluble Human Intestinal Lactoferrin Receptor: Ca(2+)-Dependent Binding to Sepharose-Based Matrices.

    Science.gov (United States)

    Oshima, Yuta; Seki, Kohei; Shibuya, Masataka; Naka, Yuki; Yokoyama, Tatsuya; Sato, Atsushi

    2016-01-01

    A soluble form of human intestinal lactoferrin receptor (shLFR) is identical to human intelectin-1 (hITLN-1), a galactofuranose-binding protein that acts as a host defense against invading pathogenic microorganisms. We found that recombinant shLFR, expressed in mammalian cells (CHO DG44, COS-1, and RK13), binds tightly to Sepharose 4 Fast Flow (FF)-based matrices in a Ca(2+)-dependent manner. This binding of shLFR to Sepharose 4 FF-based matrices was inhibited by excess D-galactose, but not by D-glucose, suggesting that shLFR recognizes repeating units of α-1,6-linked D-galactose in Sepharose 4 FF. Furthermore, shLFR could bind to both Sepharose 4B- and Sepharose 6B-based matrices that were not crosslinked in a similar manner as to Sepharose 4 FF-based matrices. Therefore, shLFR (hITLN-1) binds to Sepharose-based matrices in a Ca(2+)-dependent manner. This binding property is most likely related to the ability, as host defense lectins, to recognize sepharose (agarobiose)-like structures present on the surface of invading pathogenic microorganisms.

  7. Muscle force estimation with surface EMG during dynamic muscle contractions: a wavelet and ANN based approach.

    Science.gov (United States)

    Bai, Fengjun; Chew, Chee-Meng

    2013-01-01

    Human muscle force estimation is important in biomechanics studies, sports and assistive devices fields. Therefore, it is essential to develop an efficient algorithm to estimate force exerted by muscles. The purpose of this study is to predict force/torque exerted by muscles under dynamic muscle contractions based on continuous wavelet transform (CWT) and artificial neural networks (ANN) approaches. Mean frequency (MF) of the surface electromyography (EMG) signals power spectrum was calculated from CWT. ANN models were trained to derive the MF-force relationships from the subset of EMG signals and the measured forces. Then we use the networks to predict the individual muscle forces for different muscle groups. Fourteen healthy subjects (10 males and 4 females) were voluntarily recruited in this study. EMG signals were collected from the biceps brachii, triceps, hamstring and quadriceps femoris muscles to evaluate the proposed method. Root mean square errors (RMSE) and correlation coefficients between the predicted forces and measured actual forces were calculated.

  8. FORCE RIPPLE SUPPRESSION TECHNOLOGY FOR LINEAR MOTORS BASED ON BACK PROPAGATION NEURAL NETWORK

    Institute of Scientific and Technical Information of China (English)

    ZHANG Dailin; CHEN Youping; AI Wu; ZHOU Zude; KONG Ching Tom

    2008-01-01

    Various force disturbances influence the thrust force of linear motors when a linear motor (LM) is running. Among all of force disturbances, the force ripple is the dominant while a linear motor runs in low speed. In order to suppress the force ripple, back propagation(BP) neural network is proposed to learn the function of the force ripple of linear motors, and the acquisition method of training samples is proposed based on a disturbance observer. An off-line BP neural network is used mainly because of its high running efficiency and the real-time requirement of the servo control system of a linear motor. By using the function, the force ripple is on-line compensated according to the position of the LM. The experimental results show that the force ripple is effectively suppressed by the compensation of the BP neural network.

  9. CA19-9 as a Potential Target for Radiolabeled Antibody-Based Positron Emission Tomography of Pancreas Cancer

    Directory of Open Access Journals (Sweden)

    Mark D. Girgis

    2011-01-01

    Full Text Available Introduction. Sensitive and specific imaging of pancreas cancer are necessary for accurate diagnosis, staging, and treatment. The vast majority of pancreas cancers express the carbohydrate tumor antigen CA19-9. The goal of this study was to determine the potential to target CA19-9 with a radiolabeled anti-CA19-9 antibody for imaging pancreas cancer. Methods. CA19-9 was quantified using flow cytometry on human pancreas cancer cell lines. An intact murine anti-CA19-9 monoclonal antibody was labeled with a positron emitting radionuclide (Iodine-124 and injected into mice harboring antigen positive and negative xenografts. MicroPET/CT were performed at successive time intervals (72 hours, 96 hours, 120 hours after injection. Radioactivity was measured in blood and tumor to provide objective confirmation of the images. Results. Antigen expression by flow cytometry revealed approximately 1.3×106 CA19-9 antigens for the positive cell line and no expression in the negative cell line. Pancreas xenograft imaging with Iodine-124-labeled anti-CA19-9 mAb demonstrated an average tumor to blood ratio of 5 and positive to negative tumor ratio of 20. Conclusion. We show in vivo targeting of our antigen positive xenograft with a radiolabeled anti-CA19-9 antibody. These data demonstrate the potential to achieve anti-CA19-9 antibody based positron emission tomography of pancreas cancer.

  10. Tricalcium phosphate based resorbable ceramics: Influence of NaF and CaO addition

    Energy Technology Data Exchange (ETDEWEB)

    Seeley, Zachary; Bandyopadhyay, Amit [W. M. Keck Biomedical Materials Research Lab, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164 (United States); Bose, Susmita [W. M. Keck Biomedical Materials Research Lab, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164 (United States)], E-mail: sbose@wsu.edu

    2008-01-10

    Resorbable bioceramics have gained much attention due to their time-varying mechanical properties in-vivo. Implanted ceramics degrade allowing bone in-growth and eventual replacement of the artificial material with natural tissue. Calcium phosphate based materials have caught the most significant attention because of their excellent biocompatibility and compositional similarities to natural bone. Doping these ceramics with various metal ions has significantly influenced their properties. In this study, tricalcium phosphate (TCP) compacts were fabricated via uniaxial compression with five compositions: (i) pure TCP, (ii) TCP with 2.0 wt.% NaF, (iii) TCP with 3.0 wt.% CaO, (iv) TCP with a binary of 2.0 wt.% NaF and 0.5 wt.% Ag{sub 2}O, and (v) TCP with a quaternary of 1.0 wt.% TiO{sub 2}, 0.5 wt.% Ag{sub 2}O, 2.0 wt.% NaF, and 3.0 wt.% CaO. These compacts were sintered at 1250 deg. C for 4 h to obtain dense ceramic structures. Phase analyses were carried out using X-ray diffraction. The presence of NaF in TCP improved densification and increased compression strength from 70 ({+-} 25) to 130 ({+-} 40) MPa. Addition of CaO had no influence on density or strength. Human osteoblast cell growth behavior was studied using an osteoprecursor cell line (OPC 1) to assure that the biocompatibility of these ceramics was not altered due to the dopants. For long-term biodegradation studies, density, weight change, surface microstructure, and uniaxial compression strength were measured as a function of time in a simulated body fluid (SBF). Weight gain in SBF correlated strongly with precipitation viewed in the inter-connected pores of the samples. After 3 months in SBF, all samples displayed a reduction in strength. NaF, CaO and the quaternary compositions maintained the most steady strength loss under SBF.

  11. In vitro and in vivo evaluation of zinc-modified ca-si-based ceramic coating for bone implants.

    Science.gov (United States)

    Yu, Jiangming; Li, Kai; Zheng, Xuebin; He, Dannong; Ye, Xiaojian; Wang, Meiyan

    2013-01-01

    The host response to calcium silicate ceramic coatings is not always favorable because of their high dissolution rates, leading to high pH within the surrounding physiological environment. Recently, a zinc-incorporated calcium silicate-based ceramic Ca2ZnSi2O7 coating, developed on a Ti-6Al-4V substrate using plasma-spray technology, was found to exhibit improved chemical stability and biocompatibility. This study aimed to investigate and compare the in vitro response of osteoblastic MC3T3-E1 cells cultured on Ca2ZnSi2O7 coating, CaSiO3 coating, and uncoated Ti-6Al-4V titanium control at cellular and molecular level. Our results showed Ca2ZnSi2O7 coating enhanced MC3T3-E1 cell attachment, proliferation, and differentiation compared to CaSiO3 coating and control. In addition, Ca2ZnSi2O7 coating increased mRNA levels of osteoblast-related genes (alkaline phosphatase, procollagen α1(I), osteocalcin), insulin-like growth factor-I (IGF-I), and transforming growth factor-β1 (TGF-β1). The in vivo osteoconductive properties of Ca2ZnSi2O7 coating, compared to CaSiO3 coating and control, was investigated using a rabbit femur defect model. Histological and histomorphometrical analysis demonstrated new bone formation in direct contact with the Ca2ZnSi2O7 coating surface in absence of fibrous tissue and higher bone-implant contact rate (BIC) in the Ca2ZnSi2O7 coating group, indicating better biocompatibility and faster osseointegration than CaSiO3 coated and control implants. These results indicate Ca2ZnSi2O7 coated implants have applications in bone tissue regeneration, since they are biocompatible and able to osseointegrate with host bone.

  12. Application of CaO-Based Bed Material for Dual Fluidized Bed Steam Biomass Gasification

    Science.gov (United States)

    Koppatz, S.; Pfeifer, C.; Kreuzeder, A.; Soukup, G.; Hofbauer, H.

    Gasification of biomass is a suitable option for decentralized energy supply based on renewable sources in the range of up to 50 MW fuel input. The paper presents the dual fluidized bed (DFB) steam gasification process, which is applied to generate high quality and nitrogen-free product gas. Essential part of the DFB process is the bed material used in the fluidized reactors, which has significant impact on the product gas quality. By the use of catalytically active bed materials the performance of the overall process is increased, since the bed material favors reactions of the steam gasification. In particular, tar reforming reactions are favored. Within the paper, the pilot plant based on the DFB process with 100kW fuel input at Vienna University of Technology, Austria is presented. Actual investigations with focus on CaO-based bed materials (limestone) as well as with natural olivine as bed material were carried out at the pilot plant. The application of CaO-based bed material shows mainly decreased tar content in the product gas in contrast to experiments with olivine as bed material. The paper presents the results of steam gasification experiments with limestone and olivine, whereby the product gas composition as well as the tar content and the tar composition are outlined.

  13. Installation Development Environmental Assessment Travis Air Force Base, California

    Science.gov (United States)

    2007-11-01

    area predominantly have a thermic soil temperature regime (the mean annual soil temperature is 15 degrees Celsius [°C] or higher but lower than 22°C...ranges from sea level to 660 feet (200 meters) in the foothills surrounding the Central Valley. The valley floor is almost flat, and relief is small...even along the borders of the area. The Final EA of Installation Development Travis AFB, CA November 2007 3-15 flatness of the valley floor

  14. Model-based asessment of an in-vivo predictive relationship from CA1 to CA3 in the rodent hippocampus.

    Science.gov (United States)

    Sandler, Roman A; Song, Dong; Hampson, Robert E; Deadwyler, Sam A; Berger, Theodore W; Marmarelis, Vasilis Z

    2015-02-01

    Although an anatomical connection from CA1 to CA3 via the Entorhinal Cortex (EC) and through backprojecting interneurons has long been known it exist, it has never been examined quantitatively on the single neuron level, in the in-vivo nonpatholgical, nonperturbed brain. Here, single spike activity was recorded using a multi-electrode array from the CA3 and CA1 areas of the rodent hippocampus (N = 7) during a behavioral task. The predictive power from CA3→CA1 and CA1→CA3 was examined by constructing Multivariate Autoregressive (MVAR) models from recorded neurons in both directions. All nonsignificant inputs and models were identified and removed by means of Monte Carlo simulation methods. It was found that 121/166 (73 %) CA3→CA1 models and 96/145 (66 %) CA1→CA3 models had significant predictive power, thus confirming a predictive 'Granger' causal relationship from CA1 to CA3. This relationship is thought to be caused by a combination of truly causal connections such as the CA1→EC→CA3 pathway and common inputs such as those from the Septum. All MVAR models were then examined in the frequency domain and it was found that CA3 kernels had significantly more power in the theta and beta range than those of CA1, confirming CA3's role as an endogenous hippocampal pacemaker.

  15. A fast Na+/Ca2+-based action potential in a marine diatom.

    Directory of Open Access Journals (Sweden)

    Alison R Taylor

    Full Text Available BACKGROUND: Electrical impulses in animals play essential roles in co-ordinating an array of physiological functions including movement, secretion, environmental sensing and development. Underpinning many of these electrical signals is a fast Na+-based action potential that has been fully characterised only in cells associated with the neuromuscular systems of multicellular animals. Such rapid action potentials are thought to have evolved with the first metazoans, with cnidarians being the earliest representatives. The present study demonstrates that a unicellular protist, the marine diatom Odontella sinensis, can also generate a fast Na+/Ca2+ based action potential that has remarkably similar biophysical and pharmacological properties to invertebrates and vertebrate cardiac and skeletal muscle cells. METHODOLOGY/PRINCIPAL FINDINGS: The kinetic, ionic and pharmacological properties of the rapid diatom action potential were examined using single electrode current and voltage clamp techniques. Overall, the characteristics of the fast diatom currents most closely resemble those of vertebrate and invertebrate muscle Na+/Ca2+ currents. CONCLUSIONS/SIGNIFICANCE: This is the first demonstration of voltage-activated Na+ channels and the capacity to generate fast Na+-based action potentials in a unicellular photosynthetic organism. The biophysical and pharmacological characteristics together with the presence of a voltage activated Na+/Ca2+ channel homologue in the recently sequenced genome of the diatom Thalassiosira pseudonana, provides direct evidence supporting the hypothesis that this rapid signalling mechanism arose in ancestral unicellular eukaryotes and has been retained in at least two phylogenetically distant lineages of eukaryotes; opisthokonts and the stramenopiles. The functional role of the fast animal-like action potential in diatoms remains to be elucidated but is likely involved in rapid environmental sensing of these widespread and

  16. Status and future transition of rapid urbanizing landscape in central Western Ghats - CA based approach

    Science.gov (United States)

    Bharath, S..; Rajan, K. S.; Ramachandra, T. V.

    2014-11-01

    The land use changes in forested landscape are highly complex and dynamic, affected by the natural, socio-economic, cultural, political and other factors. The remote sensing (RS) and geographical information system (GIS) techniques coupled with multi-criteria evaluation functions such as Markov-cellular automata (CA-Markov) model helps in analysing intensity, extent and future forecasting of human activities affecting the terrestrial biosphere. Karwar taluk of Central Western Ghats in Karnataka state, India has seen rapid transitions in its forest cover due to various anthropogenic activities, primarily driven by major industrial activities. A study based on Landsat and IRS derived data along with CA-Markov method has helped in characterizing the patterns and trends of land use changes over a period of 2004-2013, expected transitions was predicted for a set of scenarios through 2013-2022. The analysis reveals the loss of pristine forest cover from 75.51% to 67.36% (1973 to 2013) and increase in agriculture land as well as built-up area of 8.65% (2013), causing impact on local flora and fauna. The other factors driving these changes are the aggregated level of demand for land, local and regional effects of land use activities such as deforestation, improper practices in expansion of agriculture and infrastructure development, deteriorating natural resources availability. The spatio temporal models helped in visualizing on-going changes apart from prediction of likely changes. The CA-Markov based analysis provides us insights into the localized changes impacting these regions and can be useful in developing appropriate mitigation management approaches based on the modelled future impacts. This necessitates immediate measures for minimizing the future impacts.

  17. Cell Adhesion on Dynamic Supramolecular Surfaces Probed by Fluid Force Microscopy-Based Single-Cell Force Spectroscopy.

    Science.gov (United States)

    Sankaran, Shrikrishnan; Jaatinen, Leena; Brinkmann, Jenny; Zambelli, Tomaso; Vörös, Janos; Jonkheijm, Pascal

    2017-04-25

    Biomimetic and stimuli-responsive cell-material interfaces are actively being developed to study and control various cell-dynamics phenomena. Since cells naturally reside in the highly dynamic and complex environment of the extracellular matrix, attempts are being made to replicate these conditions in synthetic biomaterials. Supramolecular chemistry, dealing with noncovalent interactions, has recently provided possibilities to incorporate such dynamicity and responsiveness in various types of architectures. Using a cucurbit[8]uril-based host-guest system, we have successfully established a dynamic and electrochemically responsive interface for the display of the integrin-specific ligand, Arg-Gly-Asp (RGD), to promote cell adhesion. Due to the weak nature of the noncovalent forces by which the components at the interface are held together, we expected that cell adhesion would also be weaker in comparison to traditional interfaces where ligands are usually immobilized by covalent linkages. To assess the stability and limitations of our noncovalent interfaces, we performed single-cell force spectroscopy studies using fluid force microscopy. This technique enabled us to measure rupture forces of multiple cells that were allowed to adhere for several hours on individual substrates. We found that the rupture forces of cells adhered to both the noncovalent and covalent interfaces were nearly identical for up to several hours. We have analyzed and elucidated the reasons behind this result as a combination of factors including the weak rupture force between linear Arg-Gly-Asp and integrin, high surface density of the ligand, and increase in effective concentration of the supramolecular components under spread cells. These characteristics enable the construction of highly dynamic biointerfaces without compromising cell-adhesive properties.

  18. Study of Residual TL of CaSO4:Dy-based Thermoluminescence Dosemeter.

    Science.gov (United States)

    Sahai, Manish K; Pradhan, S M; Bakshi, A K; Datta, D

    2017-04-27

    Thermoluminescence (TL) signal obtained during second readout of a TL dosemeter disc previously exposed to ionising radiation is termed as residual TL. The origin of residual TL has not been discussed in detail so far in the literature. In this work, experimentally obtained residual TL signal and its origin is studied for CaSO4:Dy-based TL dosemeter through numerical simulation and role of deeper traps has been discussed. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. CaSePer: An efficient model for personalized web page change detection based on segmentation

    OpenAIRE

    Kuppusamy, K. S.; Aghila, G.

    2014-01-01

    Users who visit a web page repeatedly at frequent intervals are more interested in knowing the recent changes that have occurred on the page than the entire contents of the web page. Because of the increased dynamism of web pages, it would be difficult for the user to identify the changes manually. This paper proposes an enhanced model for detecting changes in the pages, which is called CaSePer (Change detection based on Segmentation with Personalization). The change detection is micro-manage...

  20. Rasch model based analysis of the Force Concept Inventory

    Science.gov (United States)

    Planinic, Maja; Ivanjek, Lana; Susac, Ana

    2010-06-01

    The Force Concept Inventory (FCI) is an important diagnostic instrument which is widely used in the field of physics education research. It is therefore very important to evaluate and monitor its functioning using different tools for statistical analysis. One of such tools is the stochastic Rasch model, which enables construction of linear measures for persons and items from raw test scores and which can provide important insight in the structure and functioning of the test (how item difficulties are distributed within the test, how well the items fit the model, and how well the items work together to define the underlying construct). The data for the Rasch analysis come from the large-scale research conducted in 2006-07, which investigated Croatian high school students’ conceptual understanding of mechanics on a representative sample of 1676 students (age 17-18 years). The instrument used in research was the FCI. The average FCI score for the whole sample was found to be (27.7±0.4)% , indicating that most of the students were still non-Newtonians at the end of high school, despite the fact that physics is a compulsory subject in Croatian schools. The large set of obtained data was analyzed with the Rasch measurement computer software WINSTEPS 3.66. Since the FCI is routinely used as pretest and post-test on two very different types of population (non-Newtonian and predominantly Newtonian), an additional predominantly Newtonian sample ( N=141 , average FCI score of 64.5%) of first year students enrolled in introductory physics course at University of Zagreb was also analyzed. The Rasch model based analysis suggests that the FCI has succeeded in defining a sufficiently unidimensional construct for each population. The analysis of fit of data to the model found no grossly misfitting items which would degrade measurement. Some items with larger misfit and items with significantly different difficulties in the two samples of students do require further examination

  1. Vandenberg Air Force Base Upper Level Wind Launch Weather Constraints

    Science.gov (United States)

    Shafer, Jaclyn A.; Wheeler, Mark M.

    2012-01-01

    The 30th Operational Support Squadron Weather Flight (30 OSSWF) provides comprehensive weather services to the space program at Vandenberg Air Force Base (VAFB) in California. One of their responsibilities is to monitor upper-level winds to ensure safe launch operations of the Minuteman III ballistic missile. The 30 OSSWF tasked the Applied Meteorology Unit (AMU) to analyze VAFB sounding data with the goal of determining the probability of violating (PoV) their upper-level thresholds for wind speed and shear constraints specific to this launch vehicle, and to develop a tool that will calculate the PoV of each constraint on the day of launch. In order to calculate the probability of exceeding each constraint, the AMU collected and analyzed historical data from VAFB. The historical sounding data were retrieved from the National Oceanic and Atmospheric Administration Earth System Research Laboratory archive for the years 1994-2011 and then stratified into four sub-seasons: January-March, April-June, July-September, and October-December. The maximum wind speed and 1000-ft shear values for each sounding in each subseason were determined. To accurately calculate the PoV, the AMU determined the theoretical distributions that best fit the maximum wind speed and maximum shear datasets. Ultimately it was discovered that the maximum wind speeds follow a Gaussian distribution while the maximum shear values follow a lognormal distribution. These results were applied when calculating the averages and standard deviations needed for the historical and real-time PoV calculations. In addition to the requirements outlined in the original task plan, the AMU also included forecast sounding data from the Rapid Refresh model. This information provides further insight for the launch weather officers (LWOs) when determining if a wind constraint violation will occur over the next few hours on day of launch. The interactive graphical user interface (GUI) for this project was developed in

  2. Rasch model based analysis of the Force Concept Inventory

    Directory of Open Access Journals (Sweden)

    Maja Planinic

    2010-03-01

    Full Text Available The Force Concept Inventory (FCI is an important diagnostic instrument which is widely used in the field of physics education research. It is therefore very important to evaluate and monitor its functioning using different tools for statistical analysis. One of such tools is the stochastic Rasch model, which enables construction of linear measures for persons and items from raw test scores and which can provide important insight in the structure and functioning of the test (how item difficulties are distributed within the test, how well the items fit the model, and how well the items work together to define the underlying construct. The data for the Rasch analysis come from the large-scale research conducted in 2006-07, which investigated Croatian high school students’ conceptual understanding of mechanics on a representative sample of 1676 students (age 17–18 years. The instrument used in research was the FCI. The average FCI score for the whole sample was found to be (27.7±0.4%, indicating that most of the students were still non-Newtonians at the end of high school, despite the fact that physics is a compulsory subject in Croatian schools. The large set of obtained data was analyzed with the Rasch measurement computer software WINSTEPS 3.66. Since the FCI is routinely used as pretest and post-test on two very different types of population (non-Newtonian and predominantly Newtonian, an additional predominantly Newtonian sample (N=141, average FCI score of 64.5% of first year students enrolled in introductory physics course at University of Zagreb was also analyzed. The Rasch model based analysis suggests that the FCI has succeeded in defining a sufficiently unidimensional construct for each population. The analysis of fit of data to the model found no grossly misfitting items which would degrade measurement. Some items with larger misfit and items with significantly different difficulties in the two samples of students do require further

  3. Problem decomposition by mutual information and force-based clustering

    Science.gov (United States)

    Otero, Richard Edward

    The scale of engineering problems has sharply increased over the last twenty years. Larger coupled systems, increasing complexity, and limited resources create a need for methods that automatically decompose problems into manageable sub-problems by discovering and leveraging problem structure. The ability to learn the coupling (inter-dependence) structure and reorganize the original problem could lead to large reductions in the time to analyze complex problems. Such decomposition methods could also provide engineering insight on the fundamental physics driving problem solution. This work forwards the current state of the art in engineering decomposition through the application of techniques originally developed within computer science and information theory. The work describes the current state of automatic problem decomposition in engineering and utilizes several promising ideas to advance the state of the practice. Mutual information is a novel metric for data dependence and works on both continuous and discrete data. Mutual information can measure both the linear and non-linear dependence between variables without the limitations of linear dependence measured through covariance. Mutual information is also able to handle data that does not have derivative information, unlike other metrics that require it. The value of mutual information to engineering design work is demonstrated on a planetary entry problem. This study utilizes a novel tool developed in this work for planetary entry system synthesis. A graphical method, force-based clustering, is used to discover related sub-graph structure as a function of problem structure and links ranked by their mutual information. This method does not require the stochastic use of neural networks and could be used with any link ranking method currently utilized in the field. Application of this method is demonstrated on a large, coupled low-thrust trajectory problem. Mutual information also serves as the basis for an

  4. Defending the Joint Force: Lessons Learned from Joint Base Balad

    Science.gov (United States)

    2011-01-01

    the enemy’s aerial power by destroying his nests and eggs on the ground than to hunt his flying birds in the air.”1 This concept is reflected in Air...in defending its own assets and those of the joint force.  1. Giulio Douhet, The Command of the Air, trans. Dino Ferrari (1942; new imprint

  5. Reconstitution of the Base Force of 1995: Plan or Placebo

    Science.gov (United States)

    1993-05-14

    forcesý,umualy RCwhchdie services mantain pewactime at bvvsh I=s thai full ulSO anl d readinis Duri ng mol~ifzaion, dumes farces mu " regenerated to A... epos Of manpower, cadre uni% stockpiled and war reserve military moats research and techniology uwsbnen triiined and experienced leadership and

  6. Rasch Model Based Analysis of the Force Concept Inventory

    Science.gov (United States)

    Planinic, Maja; Ivanjek, Lana; Susac, Ana

    2010-01-01

    The Force Concept Inventory (FCI) is an important diagnostic instrument which is widely used in the field of physics education research. It is therefore very important to evaluate and monitor its functioning using different tools for statistical analysis. One of such tools is the stochastic Rasch model, which enables construction of linear…

  7. Installation Development Environmental Assessment at Scott Air Force Base, Illinois

    Science.gov (United States)

    2007-05-01

    part of the Proposed Action relative to sustainable building concepts. Where possible, the Air Force will incorporate sustainable building concepts...prOji;!Ct proponents to incorporate sustainable building ~:om:cpts into its construction asld renovation plans. These concepts may include the nse of

  8. Research on Evacuation Based on Social Force Model

    Science.gov (United States)

    Liu, W.; Deng, Z.; Li, W.; Lin, J.

    2017-09-01

    Crowded centers always cause personnel casualties in evacuation operations. Stampede events often occur by hit, squeeze and crush due to panic. It is of vital important to alleviate such situation. With the deepening of personnel evacuation research, more and more researchers are committed to study individual behaviors and self-organization phenomenon in evacuation process. The study mainly includes: 1, enrich the social force model from different facets such as visual, psychological, external force to descript more realistic evacuation; 2, research on causes and effects of self - organization phenomenon. In this paper, we focus on disorder motion that occurs in the crowded indoor publics, especially the narrow channel and safety exits and other special arteries. We put forward the improved social force model to depict pedestrians' behaviors, an orderly speed-stratification evacuation method to solve disorder problem, and shape-changed export to alleviate congestion. The result of this work shows an improvement of evacuation efficiency by 19.5 %. Guiding pedestrians' direction to slow down the influence of social forces has a guidance function in improving the efficiency of indoor emergency evacuation.

  9. Toward optical-tweezers-based force microscopy for airborne microparticles.

    Science.gov (United States)

    Power, Rory M; Burnham, Daniel R; Reid, Jonathan P

    2014-12-20

    Optical tweezers have found widespread application in biological and colloidal physics for the measurement of pN forces over nanometer to micrometer length scales. Similar aerosol-phase measurements of interparticle force have not been reported in spite of the potential to better resolve particle coagulation kinetics. Various refractive index mismatches in the beam path as well as the need to explicitly account for gravity and inertial particle motion provide a number of challenges that must be overcome to make such measurements tractable. In this regard, we demonstrate schemes by which the particle position and trap stiffness may be unambiguously measured using bright-field microscopy with resolution comparable with analogous condensed-phase measurements. Moreover, some of the challenges of working with highly dynamic aqueous particles are introduced and exploited to observe size-dependent phenomena in aerosol optical tweezers. Notably, when combined with cavity-enhanced Raman spectroscopy, this provides a unique opportunity to explore trapping forces over a continuum of particle size and refractive index. It is expected that the methods developed will provide a basis for the measurement of pairwise interaction forces in aerosol optical tweezers while providing a probe of fundamental airborne particle trapping dynamics.

  10. Simulating sustainable urban growth by using GIS and MCE based CA. The case of Famagusta, Nort Cyprus

    OpenAIRE

    Kara, Can

    2013-01-01

    ABSTRACT: This thesis utilizes “Geographical Information Systems” (GIS), “Multi Criteria Evaluation” (MCE) with “Cellular Automata” (CA) for simulating Sustainable urban growth scenarios for Famagusta and represents “Do Nothing” and “Sustainable” scenario-based spatial simulations of the City. Under Do Nothing scenario, Markov Chain probability analysis with CA models is used with temporal land use datasets based on the images from 2002 and 2011. It shows that, Famagusta is diverging from sus...

  11. Model-Based Assessment of an In-Vivo Predictive Relationship from CA1 to CA3 in the Rodent Hippocampus

    OpenAIRE

    Sandler, Roman A.; Song, Dong; Hampson, Robert E.; Deadwyler, Sam A.; Berger, Theodore W; Marmarelis, Vasilis Z.

    2014-01-01

    Although an anatomical connection from CA1 to CA3 via the Entorhinal Cortex (EC) and through backprojecting interneurons has long been known it exist, it has never been examined quantitatively on the single neuron level, in the in-vivo nonpatholgical, nonperturbed brain. Here, single spike activity was recorded using a multi-electrode array from the CA3 and CA1 areas of the rodent hippocampus (N=7) during a behavioral task. The predictive power from CA3→CA1 and CA1→CA3 was examined by constru...

  12. OPUS-Ca: a knowledge-based potential function requiring only Calpha positions.

    Science.gov (United States)

    Wu, Yinghao; Lu, Mingyang; Chen, Mingzhi; Li, Jialin; Ma, Jianpeng

    2007-07-01

    In this paper, we report a knowledge-based potential function, named the OPUS-Ca potential, that requires only Calpha positions as input. The contributions from other atomic positions were established from pseudo-positions artificially built from a Calpha trace for auxiliary purposes. The potential function is formed based on seven major representative molecular interactions in proteins: distance-dependent pairwise energy with orientational preference, hydrogen bonding energy, short-range energy, packing energy, tri-peptide packing energy, three-body energy, and solvation energy. From the testing of decoy recognition on a number of commonly used decoy sets, it is shown that the new potential function outperforms all known Calpha-based potentials and most other coarse-grained ones that require more information than Calpha positions. We hope that this potential function adds a new tool for protein structural modeling.

  13. Base force element method of complementary energy principle for large rotation problems

    Institute of Scientific and Technical Information of China (English)

    Yijiang Peng; Yinghua Liu

    2009-01-01

    Using the concept of the base forces, a new finite element method (base force element method, BFEM) based on the complementary energy principle is presented for accurate modeling of structures with large displacements and large rotations. First, the complementary energy of an element is described by taking the base forces as state variables, and is then separated into deformation and rotation parts for the case of large deformation. Second, the control equations of the BFEM based on the complementary energy principle are derived using the Lagrange multiplier method. Nonlinear procedure of the BFEM is then developed. Finally, several examples are analyzed to illustrate the reliability and accuracy of the BFEM.

  14. [Characteristic vibration analysis of M-RNA nucleic acid bases complexes (M = Ca+ and Mg+) by DFT].

    Science.gov (United States)

    Zhang, Xing-Chu; Hu, Yi-Hua; Wang, Xiao-Juan

    2009-01-01

    A density functional investigation of the interaction between calcium and magnesium univalent cations and RNA pyrimidine base (cytosine, thymine and uracil) was performed to determine geometric coordinates and free energies for all possible stable isomers at B3LYP/6-311 + G (2df, 2p) level. The most stable isomers C1M, T1M and U1M (M = Ca+ and Mg+) with the lowest free energy among the same pyrimidine base tautomers were calculated to determine the characters of infrared vibrations. According to the results, two characteristic infrared vibrations at wave numbers 1,684 and 1,765 cm(-1) were found for single pyrimidine base C1, at 1,747 and 1,792 cm(-1) for T1, 1,763 and at 1,796 cm(-1) for U1. In addition, spectrum shifts were found when the cations interact with the pyrimidine base tautomers. For deeper analysis, we found that when the stable complexes are formed, the cations are prone to act on the oxygen atoms, and cause the vibrational frequencies to change, the spectral lines belonging to the vibration of C--O--M turn out to redshift and the others turn out to blueshift. When the stable complex C1M is formed, the characteristic infrared vibration at 1,684 cm(-1) mainly caused by the ring's vibration turns out to blueshift about 10 cm(-1), and the another characteristic vibration of 1,765 cm(-1) caused by vibration of bond C--O with oxygen atom acting on cations directly turns out to redshift by 112 cm(-1) for complex C1Ca+ and by 110 cm(-1) for C1Mg+. When the stable complexes T1M are formed, the characteristic vibration of bond C--O--M turns out to redshift about 130 cm(-1) and the vibration of bond C--O turns out to blueshift about 55 cm(-1). When the stable complexes U1M are formed, the vibration of bond C--O--M turns out to redshift about 90 cm(-1) and about 50 cm(-1) for another C--O. The characteristic infrared vibration frequencies are changed obviously when tautomers act on the cations, which is mainly because cations take part in molecule's vibrations

  15. Low-temperature linear thermal rectifiers based on Coriolis forces

    Science.gov (United States)

    Suwunnarat, Suwun; Li, Huanan; Fleischmann, Ragnar; Kottos, Tsampikos

    2016-04-01

    We demonstrate that a three-terminal harmonic symmetric chain in the presence of a Coriolis force, produced by a rotating platform that is used to place the chain, can produce thermal rectification. The direction of heat flow is reconfigurable and controlled by the angular velocity Ω of the rotating platform. A simple three-terminal triangular lattice is used to demonstrate the proposed principle.

  16. Fuzzy force control of constrained robot manipulators based on impedance model in an unknown environment

    Institute of Scientific and Technical Information of China (English)

    LIU Hongyi; WANG Lei; WANG Fei

    2007-01-01

    To precisely implement the force control of robot manipulators in an unknown environment,a control strategy based on fuzzy prediction of the reference trajectory in the impedance model is developed.The force tracking experiments are executed in an open-architecture control system with different tracking velocities,different desired forces,different contact stiffnesses and different surface figurations.The corresponding force control results are compared and analyzed.The influences of unknown parameters of the environment on the contact force are analyzed based on experimental data,and the tunings of predictive scale factors are illustrated.The experimental results show that the desired trajectory in the impedance model is predicted exactly and rapidly in the cases that the contact surface is unknown,the contact stiffness changes,and the fuzzy force control algorithm has high adaptability to the unknown environment.

  17. A DFT-Based QSARs Study of Acetazolamide/Sulfanilamide Derivatives with Carbonic Anhydrase (CA-II Isozyme Inhibitory Activity

    Directory of Open Access Journals (Sweden)

    Oral Oltulu

    2007-02-01

    Full Text Available This study presents Quantitative Structure Activity Relationships (QSAR studyon a pool of 18 bio-active sulfonamide compounds which includes five acetazolamidederivatives, eight sulfanilamide derivatives and five clinically used sulfonamides moleculesas drugs namely acetazolamide, methazolamide, dichlorophenamide, ethoxolamide anddorzolamide. For all the compounds, initial geometry optimizations were carried out with amolecular mechanics (MM method using the MM force fields. The lowest energyconformations of the compounds obtained by the MM method were further optimized by theDensity Functional Theory (DFT method by employing Becke’s three-parameter hybridfunctional (B3LYP and 6-31G (d basis set. Molecular descriptors, dipole moment,electronegativity, total energy at 0 K, entropy at 298 K, HOMO and LUMO energiesobtained from DFT calculations provide valuable information and have a significant role inthe assessment of carbonic anhydrase (CA-II inhibitory activity of the compounds. By usingthe multiple linear regression technique several QSAR models have been drown up with thehelp these calculated descriptors and carbonic anhydrase (CA-II inhibitory data of themolecules. Among the obtained QSAR models presented in the study, statistically the mostsignificant one is a five parameters linear equation with the squared correlation coefficient R2 values of ca. 0.94 and the squared cross-validated correlation coefficient R2CV values of ca. 0.85. The results were discussed in the light of the main factors that influence theinhibitory activity of the carbonic anhydrase (CA-II isozyme.

  18. Joint Interference Detection Method for DSSS Communications Based on the OMP Algorithm and CA-CFAR

    Directory of Open Access Journals (Sweden)

    Zhang Yongshun

    2016-01-01

    Full Text Available The existing direct sequence spread spectrum (DSSS communications interference detection algorithms are confined to the high sampling rate. In order to solve this problem, algorithm for DSSS communications interference detection was designed based on compressive sensing (CS. First of all, the orthogonal matching pursuit (OMP algorithm was applied to the interference detection in DSSS communications, the advantages and weaknesses of the algorithm were analyzed; Secondly, according to the weaknesses of the OMP algorithm, a joint interference detection method based on the OMP algorithm and cell average constant false alarm rate (CA-CFAR was proposed. The theoretical analyze and computer simulation all proved the effectiveness of the new algorithm. The simulation results show that the new method not only could achieve the interference detection, but also could estimate the interference quantity effectively.

  19. SR-71 Tail #844 Landing at Edwards Air Force Base

    Science.gov (United States)

    1996-01-01

    With distinctive heat waves trailing behind its engines, NASA Dryden Flight Research Center's SR-71A, tail number 844, lands at the Edwards AFB runway after a 1996 flight. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and sideslip, which are normally obtained with small tubes and vanes extending into the airstream. One of Dryden's SR-71s was used for the Linear Aerospike Rocket Engine, or LASRE Experiment. Another earlier project consisted of a series of flights using the SR-71 as a science camera platform for NASA's Jet Propulsion Laboratory in Pasadena, California. An upward

  20. Study on the Driving Forces of Rocky Desertification in Guizhou Province Based on Variation Coefficient Method

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to study the driving forces of rocky desertification in Guizhou Province. [Method] Based on GIS and RS technology, the main driving forces of rocky desertification in Guizhou Province were analyzed by means of correlation analysis and variation coefficient method, and then the distribution of rocky desertification in Guizhou Province was assessed synthetically. [Result] The main driving forces of rocky desertification in Guizhou Province were vegetation cover, rainfall, peasant incom...

  1. Research of a Novel Three-dimensional Force Flexible Tactile Sensor Based on Conductive Rubber

    Directory of Open Access Journals (Sweden)

    Fei Xu

    2010-09-01

    Full Text Available A novel three-dimensional force flexible tactile sensor using conductive rubber with "overall injection molding" technique is presented. The sensor is based on conductive rubber’s force-sensitive property. The sensor is flexible and can measure 3-D force. The rubber’s characteristics, the sensor’s structure and its principle are described. The results of simulation will be also presented.

  2. Ca analysis: an Excel based program for the analysis of intracellular calcium transients including multiple, simultaneous regression analysis.

    Science.gov (United States)

    Greensmith, David J

    2014-01-01

    Here I present an Excel based program for the analysis of intracellular Ca transients recorded using fluorescent indicators. The program can perform all the necessary steps which convert recorded raw voltage changes into meaningful physiological information. The program performs two fundamental processes. (1) It can prepare the raw signal by several methods. (2) It can then be used to analyze the prepared data to provide information such as absolute intracellular Ca levels. Also, the rates of change of Ca can be measured using multiple, simultaneous regression analysis. I demonstrate that this program performs equally well as commercially available software, but has numerous advantages, namely creating a simplified, self-contained analysis workflow.

  3. Novel thermoluminescence foils for 2-D clinical dosimetry, based on CaSO{sub 4}:Dy

    Energy Technology Data Exchange (ETDEWEB)

    Klosowski, M., E-mail: mariusz.klosowski@ifj.edu.p [Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Czopyk, L. [Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Kisielewicz, K.; Kabat, D. [Centre of Oncology, Maria Sklodowska-Curie Memorial Institute, ul. Garncarska 11, 31-115 Krakow (Poland); Olko, P. [Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Waligorski, M.P.R. [Centre of Oncology, Maria Sklodowska-Curie Memorial Institute, ul. Garncarska 11, 31-115 Krakow (Poland)

    2010-03-15

    The newly developed two-dimensional thermoluminescence (TL) foils made from CaSO{sub 4}:Dy TL powder and the high temperature polymer PFA, were tested for their dosimetric properties. The results were evaluated using laboratory TL reader with PCO CCD camera and round planchet heater, 72 mm in diameter. 55 x 55 x 0.3 mm{sup 3} foils were tested for dose response, reproducibility and spatial resolution. It was found that the detectors are linear up to at least 2 Gy and their spatial resolution is about 1 mm. A loss of sensitivity with repeated re-uses was observed (9% in 10 uses). It is attributable to the darkening of the detector due to oxidizing of impurities gathering at its surface and may be avoided by application of proper cleaning procedure. The foils were tested for measurements of 2-D dose distribution on 60 MeV proton beam at IFJ Krakow. The results show that 2-D TL foils based on CaSO{sub 4}:Dy can be a useful tool for quality assurance of proton beams.

  4. Natural CaO-TiO2-SiO2 based ceramics

    Directory of Open Access Journals (Sweden)

    Jelena Pantić

    2011-06-01

    Full Text Available Lešnica river deposits consist of a large number of minerals of different grain sizes including sphene. Since it is very difficult to obtain pure monophase titanite by different synthetic routes (sol-gel, coprecipitation, combustion, spray pyrolysis and hydrothermal method, the aim of this work was to study the structure of the sphene from the Lešnica river deposits and possibility of using it as a natural precursor for CaO-TiO2-SiO2 based ceramics. The sphene from Lešnica was analyzed by different methods: tristimulus colorimetry, infrared spectroscopy, electron microprobe and X-ray single crystal diffraction. It was confirmed that Al, Fe, Mn and P are present in the sphene structure and proposed that corresponding structural formula could be: (Ca2+1.008 Mn2+0.0021.010(Ti4+0.901 Fe3+0.033 Al3+0.060 P5+0.0010.995 Si4+1.024 O2-5.

  5. 77 FR 5781 - Record of Decision for the Air Space Training Initiative Shaw Air Force Base, South Carolina...

    Science.gov (United States)

    2012-02-06

    ... Department of the Air Force Record of Decision for the Air Space Training Initiative Shaw Air Force Base... Decision (ROD). SUMMARY: On December 9, 2011, the United States Air Force signed the ROD for the Airspace Training Initiative Shaw Air Force Base, South Carolina Final Environmental Impact Statement (EIS). The...

  6. Compliant landing of a trotting quadruped robot based on hybrid motion/force robust control

    Institute of Scientific and Technical Information of China (English)

    郎琳; 王剑; 韦庆; 马宏绪

    2016-01-01

    A compliant landing strategy for a trotting quadruped robot on unknown rough terrains based on contact force control is presented. Firstly, in order to lower the disturbance caused by the landing impact force, a landing phase is added between the swing phase and the stance phase, where the desired contact force is set as a small positive constant. Secondly, the joint torque optimization of the stance legs is formulated as a quadratic programming (QP) problem subject to equality and inequality/bound constraints. And a primal-dual dynamical system solver based on linear variational inequalities (LVI) is applied to solve this QP problem. Furthermore, based on the optimization results, a hybrid motion/force robust controller is designed to realize the tracking of the contact force, while the constraints of the stance feet landing angles are fulfilled simultaneously. Finally, the experiments are performed to validate the proposed methods.

  7. Physics-Based Visual Characterization of Molecular Interaction Forces.

    Science.gov (United States)

    Hermosilla, Pedro; Estrada, Jorge; Guallar, Victor; Ropinski, Timo; Vinacua, Alvar; Vazquez, Pere-Pau

    2017-01-01

    Molecular simulations are used in many areas of biotechnology, such as drug design and enzyme engineering. Despite the development of automatic computational protocols, analysis of molecular interactions is still a major aspect where human comprehension and intuition are key to accelerate, analyze, and propose modifications to the molecule of interest. Most visualization algorithms help the users by providing an accurate depiction of the spatial arrangement: the atoms involved in inter-molecular contacts. There are few tools that provide visual information on the forces governing molecular docking. However, these tools, commonly restricted to close interaction between atoms, do not consider whole simulation paths, long-range distances and, importantly, do not provide visual cues for a quick and intuitive comprehension of the energy functions (modeling intermolecular interactions) involved. In this paper, we propose visualizations designed to enable the characterization of interaction forces by taking into account several relevant variables such as molecule-ligand distance and the energy function, which is essential to understand binding affinities. We put emphasis on mapping molecular docking paths obtained from Molecular Dynamics or Monte Carlo simulations, and provide time-dependent visualizations for different energy components and particle resolutions: atoms, groups or residues. The presented visualizations have the potential to support domain experts in a more efficient drug or enzyme design process.

  8. Finite Element Response Sensitivity Analysis: a comparison between force-based and Displacement-Based Frame Element Models

    OpenAIRE

    Barbato, Michele; Conte, J P

    2005-01-01

    This paper focuses on a comparison between displacement-based and force-based elements for static and dynamic response sensitivity analysis of frame type structures. Previous research has shown that force-based frame elements are superior to classical displacement-based elements enabling, at no significant additional computational costs, a drastic reduction in the number of elements required for a given level of accuracy in the simulated response. The present work shows that this advantage of...

  9. Interrogation of Single Synthetic Polymer Chains and Polysaccharides by AFM-Based Force Spectroscopy

    NARCIS (Netherlands)

    Giannotti, M.I.; Vancso, Gyula J.

    2007-01-01

    This contribution reviews selected mechanical experiments on individual flexible macromolecules using single-molecule force spectroscopy (SMFS) based on atomic force microscopy. Focus is placed on the analysis of elasticity and conformational changes in single polymer chains upon variation of the ex

  10. Lightweight-compact variable-gap undulator with force cancellation system based on multipole monolithic magnets

    Science.gov (United States)

    Kinjo, Ryota; Kagamihata, Akihiro; Seike, Takamitsu; Kishimoto, Hikaru; Ohashi, Haruhiko; Yamamoto, Shigeru; Tanaka, Takashi

    2017-07-01

    A lightweight-compact variable-gap undulator (LCVGU) having the force-cancellation system based on the multipole monolithic magnets (MMMs) has been developed. The LCVGU is free from the heavy mechanical frames, which is a fundamental element specific to conventional variable-gap undulators (VGUs) because of a strong attractive force, and thus the cost and time for construction and installation are expected to be significantly reduced; the MMMs counteract the strong attractive force in a cost-effective manner. Results of mechanical tests and magnetic-field measurements of two prototype LCVGUs equipped with the proposed force cancellation system have revealed the comparable performance with the conventional VGUs.

  11. TMX1 determines cancer cell metabolism as a thiol-based modulator of ER-mitochondria Ca2+ flux.

    Science.gov (United States)

    Raturi, Arun; Gutiérrez, Tomás; Ortiz-Sandoval, Carolina; Ruangkittisakul, Araya; Herrera-Cruz, Maria Sol; Rockley, Jeremy P; Gesson, Kevin; Ourdev, Dimitar; Lou, Phing-How; Lucchinetti, Eliana; Tahbaz, Nasser; Zaugg, Michael; Baksh, Shairaz; Ballanyi, Klaus; Simmen, Thomas

    2016-08-15

    The flux of Ca(2+) from the endoplasmic reticulum (ER) to mitochondria regulates mitochondria metabolism. Within tumor tissue, mitochondria metabolism is frequently repressed, leading to chemotherapy resistance and increased growth of the tumor mass. Therefore, altered ER-mitochondria Ca(2+) flux could be a cancer hallmark, but only a few regulatory proteins of this mechanism are currently known. One candidate is the redox-sensitive oxidoreductase TMX1 that is enriched on the mitochondria-associated membrane (MAM), the site of ER-mitochondria Ca(2+) flux. Our findings demonstrate that cancer cells with low TMX1 exhibit increased ER Ca(2+), accelerated cytosolic Ca(2+) clearance, and reduced Ca(2+) transfer to mitochondria. Thus, low levels of TMX1 reduce ER-mitochondria contacts, shift bioenergetics away from mitochondria, and accelerate tumor growth. For its role in intracellular ER-mitochondria Ca(2+) flux, TMX1 requires its thioredoxin motif and palmitoylation to target to the MAM. As a thiol-based tumor suppressor, TMX1 increases mitochondrial ATP production and apoptosis progression. Copyright © 2016 Raturi et al.

  12. Measurement of nano particle adhesion by atomic force microscopy using probability theory based analysis

    Science.gov (United States)

    Geiger, D.; Schrezenmeier, I.; Roos, M.; Neckernuss, T.; Lehn, M.; Marti, O.

    2017-05-01

    We present a method to detect adhesive forces of nano particles by analysis of the distribution of measured lateral forces. The measurement protocol is suitable for all types of atomic force microscopes with a lateral force channel. Lateral forces are measured, in constant normal force contact mode, by scanning of substrates decorated with nano beads. By using probability theory, geometry based measurement errors are compensated and the real adhesion force is determined within a given confidence interval. The theoretical model can be adapted for particles with arbitrary shape and distribution of adhesion forces. It is applied to the adhesion problem of spherical particles with a Gaussian distribution of adhesion forces. We analyze the measured force distribution qualitatively and quantitatively. The theory predicts a systematic underestimation of the mean value of any particle adhesion measurement done by lateral pushing. Real measurement data of 50 nm diameter silica nano beads on silicon substrate is used to test the theoretical model for plausibility by means of information theory.

  13. Carbon fibre tips for scanning probe microscopy based on quartz tuning fork force sensors

    Energy Technology Data Exchange (ETDEWEB)

    Castellanos-Gomez, A; Agrait, N; Rubio-Bollinger, G, E-mail: gabino.rubio@uam.es [Departamento de Fisica de la Materia Condensada (C-III), Universidad Autonoma de Madrid, Campus de Cantoblanco, 28049 Madrid (Spain)

    2010-04-09

    We report the fabrication and the characterization of carbon fibre tips for use in combined scanning tunnelling and force microscopy based on piezoelectric quartz tuning fork force sensors. We find that the use of carbon fibre tips results in a minimum impact on the dynamics of quartz tuning fork force sensors, yielding a high quality factor and, consequently, a high force gradient sensitivity. This high force sensitivity, in combination with high electrical conductivity and oxidation resistance of carbon fibre tips, make them very convenient for combined and simultaneous scanning tunnelling microscopy and atomic force microscopy measurements. Interestingly, these tips are quite robust against occasionally occurring tip crashes. An electrochemical fabrication procedure to etch the tips is presented that produces a sub-100-nm apex radius in a reproducible way which can yield high resolution images.

  14. Extended neural network-based scheme for real-time force tracking with magnetorheological dampers

    DEFF Research Database (Denmark)

    Weber, Felix; Bhowmik, Subrata; Høgsberg, Jan Becker

    2014-01-01

    This paper validates numerically and experimentally a new neural network-based real-time force tracking scheme for magnetorheological (MR) dampers on a five-storey shear frame with MR damper. The inverse model is trained with absolute values of measured velocity and force because the targeted...... current is a positive quantity. The validation shows accurate results except of small current spikes when the desired force is in the vicinity of the residual MR damper force. In the closed-loop, higher frequency components in the current are triggered by the transition of the actual MR damper force from...... the pre-yield to the post-yield region. A control-oriented approach is presented to compensate for these drawbacks. The resulting control force tracking scheme is validated for the emulation of viscous damping, clipped viscous damping with negative stiffness, and friction damping with negative stiffness...

  15. Optical fibre bragg gratings based magnetic force measurement of magnetic bearings

    Science.gov (United States)

    Ding, Guoping; Zhou, Zude; Hu, Yefa; Zhou, Jianhua

    2008-12-01

    Magnetic bearings are typical electromechanical systems of high performance. Current-displacement-force relationship between stator and rotor is an important research topic of magnetic bearings. The critical issue is to realize magnetic force online dynamic measurement. This paper presents a novel method on magnetic force measurement of magnetic bearings with optical fibre bragg gratings (FBG), which realizes a non-contact and online force measurement with simple configuration, good noise immunity even when the rotor is running. A novel micro force transducer is designed and fabricated, which is mounted within the stator magnetic pole. To obtain current-displacement-force relationship a FBG based magnetic force measurement test rig is setup to simulate magnetic bearing working states as the stator coils currents, air gap between stator and rotor, rotor speed is adjustable. Magnetic force is measured under three classifications of test conditions and test results are presented. The measurement data show good consistency with the theory analysis and calculation, which means that the FBG based magnetic force measurement is available and of good accuracy.

  16. Some issues on atomic force microscopy based surface characterization

    Institute of Scientific and Technical Information of China (English)

    CHEN Yu-hang; HUANG Wen-hao

    2007-01-01

    Influences of tip radius and sampling interval on applying atomic force microscopy(AFM)in quantitative surface evaluations are investigated by numerical simulations and experiments. Several evaluation parameters of surfaces ranging from amplitude to functional parameters are studied. Numerical and experimental results are in good agreements. The accuracy of estimating tip radius on random rough surface with Gaussian distribution of heights using a blind reconstruction method is also discussed theoretically. It is found that the accuracy is greatly depending on the ratio of actual tip radius to rootmean-square (rms) radius of curvature. To obtain an accurate estimation of tip radius under Gaussian rough surface, the ratio has to be larger than 3/2.

  17. Mechanically induced silyl ester cleavage under acidic conditions investigated by AFM-based single-molecule force spectroscopy in the force-ramp mode.

    Science.gov (United States)

    Schmidt, Sebastian W; Pill, Michael F; Kersch, Alfred; Clausen-Schaumann, Hauke; Beyer, Martin K

    2014-01-01

    AFM-based dynamic single-molecule force spectroscopy was used to stretch carboxymethylated amylose (CMA) polymers, which have been covalently tethered between a silanized glass substrate and a silanized AFM tip via acid-catalyzed ester condensation at pH 2.0. Rupture forces were measured as a function of temperature and force loading rate in the force-ramp mode. The data exhibit significant statistical scattering, which is fitted with a maximum likelihood estimation (MLE) algorithm. Bond rupture is described with a Morse potential based Arrhenius kinetics model. The fit yields a bond dissociation energy De = 35 kJ mol(-1) and an Arrhenius pre-factor A = 6.6 × 10(4) s(-1). The bond dissociation energy is consistent with previous experiments under identical conditions, where the force-clamp mode was employed. However, the bi-exponential decay kinetics, which the force-clamp results unambiguously revealed, are not evident in the force-ramp data. While it is possible to fit the force-ramp data with a bi-exponential model, the fit parameters differ from the force-clamp experiments. Overall, single-molecule force spectroscopy in the force-ramp mode yields data whose information content is more limited than force-clamp data. It may, however, still be necessary and advantageous to perform force-ramp experiments. The number of successful events is often higher in the force-ramp mode, and competing reaction pathways may make force-clamp experiments impossible.

  18. TPR and TPD studies of effects of Cu and Ca promotion on Fe-Zn-based Fischer-Tropsch catalysts

    Indian Academy of Sciences (India)

    Olusola O James; Biswajit Chowdhury; Sudip Maity

    2013-05-01

    Temperature-programmed reduction (TPR) and temperature-programmed desorption (TPD) were used to study the effects of Cu and Ca promotion on Fe-Zn-based Fischer-Tropsch catalysts. The reduction temperature for Fe2O3 → Fe3O4 was unaffected by Ca addition but decreased when promoted with Cu. Fe-Zn promoted with Cu and Ca showed even much lower reduction temperature for Fe2O3→Fe3O4. Ca promotion enhances carburization and increases surface acidity and basicity of the Fe-Zn oxide precursor. While Cu inhibits carburization and decreases the surface acidity and basicity of the Fe-Zn oxide precursor. The implications of these effects on the application of catalysts for FT are discussed.

  19. Hybrid Force Control Based on ICMAC for an Astronaut Rehabilitative Training Robot

    Directory of Open Access Journals (Sweden)

    Lixun Zhang

    2012-08-01

    Full Text Available A novel Astronaut Rehabilitative Training Robot (ART based on a cable‐driven mechanism is represented in this paper. ART, a typical passive force servo system, can help astronauts to bench press in a microgravity environment. The purpose of this paper is to design controllers to eliminate the surplus force caused by an astronaut’s active movements. Based on the dynamics modelling of the cable‐driven unit, a hybrid force controller based on improved credit assignment CMAC (ICMAC is presented. A planning method for the cable tension is proposed so that the dynamic load produced by the ART can realistically simulate the gravity and inertial force of the barbell in a gravity environment. Finally, MATLAB simulation results of the man‐machine cooperation system are provided in order to verify the effectiveness of the proposed control strategy. The simulation results show that the hybrid control method based on the structure invariance principle can inhibit the surplus force and that ICMAC can improve the dynamic performance of the passive force servo system. Furthermore, the hybrid force controller based on ICMAC can ensure the stability of the system.

  20. A comparative study based on the first principles calculations of ATiO3 ( A = Ba, Ca, Pb and Sr) perovskite structure

    Science.gov (United States)

    Kamruzzaman, M.; Helal, M. A.; Ara, I. E.; Farid Ul Islam, A. K. M.; Rahaman, M. M.

    2016-10-01

    Structural, electronic, elastic, thermodynamic, vibrational and optical properties of the cubic phase of ATiO3 ( A = Ba, Ca, Pb and Sr) crystals have been carried out based on the density functional theory (DFT). The calculated equilibrium lattice parameters, band structures, elastic constants and the elastic moduli of ATiO3 are in good agreement with the theoretical and experimental results. The ferroelectric phenomenon of the crystals has been analyzed based on the nature of their phonon spectra. The phonon frequencies and the Born effective charges have been calculated to elucidate the ferroelectric instability of the cubic phase of ATiO3 by calculating the interatomic forces for several small displacements consistent with the symmetry of modes.

  1. In vitro and in vivo evaluation of zinc-modified ca-si-based ceramic coating for bone implants.

    Directory of Open Access Journals (Sweden)

    Jiangming Yu

    Full Text Available The host response to calcium silicate ceramic coatings is not always favorable because of their high dissolution rates, leading to high pH within the surrounding physiological environment. Recently, a zinc-incorporated calcium silicate-based ceramic Ca2ZnSi2O7 coating, developed on a Ti-6Al-4V substrate using plasma-spray technology, was found to exhibit improved chemical stability and biocompatibility. This study aimed to investigate and compare the in vitro response of osteoblastic MC3T3-E1 cells cultured on Ca2ZnSi2O7 coating, CaSiO3 coating, and uncoated Ti-6Al-4V titanium control at cellular and molecular level. Our results showed Ca2ZnSi2O7 coating enhanced MC3T3-E1 cell attachment, proliferation, and differentiation compared to CaSiO3 coating and control. In addition, Ca2ZnSi2O7 coating increased mRNA levels of osteoblast-related genes (alkaline phosphatase, procollagen α1(I, osteocalcin, insulin-like growth factor-I (IGF-I, and transforming growth factor-β1 (TGF-β1. The in vivo osteoconductive properties of Ca2ZnSi2O7 coating, compared to CaSiO3 coating and control, was investigated using a rabbit femur defect model. Histological and histomorphometrical analysis demonstrated new bone formation in direct contact with the Ca2ZnSi2O7 coating surface in absence of fibrous tissue and higher bone-implant contact rate (BIC in the Ca2ZnSi2O7 coating group, indicating better biocompatibility and faster osseointegration than CaSiO3 coated and control implants. These results indicate Ca2ZnSi2O7 coated implants have applications in bone tissue regeneration, since they are biocompatible and able to osseointegrate with host bone.

  2. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This report presents information concerning field procedures employed during the monitoring, well construction, well purging, sampling, and well logging at the Wright-Patterson Air Force Base. Activities were conducted in an effort to evaluate ground water contamination.

  3. 2008 Northwest Florida Water Management District (NWFWMD) Lidar: Eglin Air Force Base, Walton County, FL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In the summer of 2008, the Northwest Florida Water Management District collected lidar data over a portion of Walton County, FL (Eglin Air force Base) to support...

  4. Temporal Geophysical Investigations of the FT-2-Plume at the Wurtsmith Air Force Base, Oscoda, Michigan

    Science.gov (United States)

    The decommissioned Wurtsmith Air Force Base former Fire Training Cell (FT-02) facility has been the focus of several geophysical investigations. After several decades of fire training exercises, significant amounts of hydrocarbons and some solvents seeped into the subsurface cont...

  5. 2008 Northwest Florida Water Management District Lidar: Eglin Air Force Base, Walton County, FL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In the summer of 2008, the Northwest Florida Water Management District collected lidar data over a portion of Walton County, FL (Eglin Air force Base) to support...

  6. Ca(2+) sensitisation of force production by noradrenaline in femoral conductance and resistance arteries from rats with postinfarction congestive heart failure

    DEFF Research Database (Denmark)

    Trautner, Simon; Amtorp, Ole; Boesgaard, Soren

    2006-01-01

    In this study we tested the hypothesis that arterial myofilament Ca(2+) sensitivity and/or the Ca(2+) sensitising effect of noradrenaline (NA) is enhanced in post-infarction congestive heart failure (CHF), which could contribute to the high peripheral vascular resistance in this condition. Femora...

  7. Improvement of routes and production of CaSO{sub 4}-based dosimeters with unusual doping; Aprimoramento de rotas e producao de dosimetros a base de CaSO{sub 4} com dopagens nao usuais

    Energy Technology Data Exchange (ETDEWEB)

    Junot, Danilo Oliveira

    2017-07-01

    The widespread use of ionizing radiation in medicine and industry, associated with the known risks that this type of radiation can cause, has motivated the search for new radiation detectors, seeking improvements in the dosimetric characteristics and in the cost of production in comparison with commercial dosimeters disseminated. The motivation of this work is, therefore, to produce new thermoluminescent detectors through improved routes. Unusual elements in CaSO{sub 4} matrix doping, such as terbium (Tb) and ytterbium (Yb), were used as dopants in this matrix, as well as the europium (Eu), the thulium (Tm) and the silver (Ag), resulting in samples of CaSO{sub 4}:Eu,Tb, CaSO{sub 4}:Tb,Yb, CaSO{sub 4}:Tm,Ag and CaSO{sub 4}:Eu,Ag that were prepared by means of an adaptation of the method developed by Yamashita (1971). The route of synthesis is based on the mixture of calcium carbonate (CaCO{sub 3}) and dopant oxide (except for silver, incorporated in the form of metallic nanoparticles) in a solution of sulfuric acid. The mixture is heated until all the acid evaporates and only the powder of the material remains. In this route, the sulfuric acid is collected and can be reused. The phosphors produced were characterized by X-ray diffraction and radioluminescence techniques. The silver particles, produced by the polyol method, were characterized by scanning electron microscopy. Composites were obtained from the addition of Teflon to the phosphors. The thermoluminescence (TL) and the optically stimulated luminescence (OSL) of the new materials produced were investigated. Thermoluminescent characteristics such as sensitivity, linearity, reproducibility, minimum detectable dose, kinetic order and fading were evaluated and discussed. The CaSO{sub 4}:Tb,Eu composites showed TL glow curves with peaks at temperatures of 170 °C, 270 °C and 340 °C. The CaSO{sub 4}:Tb,Yb composites presented TL glow curves with peaks at temperatures of 90 °C, 160 °C, 240 °C and 340 °C. Ca

  8. Improving the Recreational Fishery on Malmstrom Air Force Base

    Science.gov (United States)

    2010-08-01

    29 3.9.1 History of Malmstrom AFB...3.9.1 History of Malmstrom AFB Construction for an Army Air Corps base east of Great Falls began in 1942. Known as Great Falls Army Air Base, its...Bottom dwelling; Kootenai River Kootenai River population Grizzly Bear Ursus arctos horribilis T Alpine/subalpine coniferous

  9. Hydrogen Peroxide Sensor Based on Horseradish Peroxidase Combined with CaCO3 Microspheres and Gold Nanoparticles

    Institute of Scientific and Technical Information of China (English)

    ZHENG Li; JIANG Feng-hua; MA Guang-ran; ZHUANG Qian-fen; LI Feng

    2011-01-01

    Direct electrochemistry and electrocatalysis of horseradish peroxidase(HRP) were achieved by entrapping the enzyme between CaCO3 microspheres and gold nanoparticles through forming sandwich configuration (CaCO3-HRP-AuNPs).Polyanion,poly(styrene sulfonate)(PSS),was hybrid with CaCO3 microspheres to increase the surface negative charges for binding with HRP through electrostatic interaction.After the bioconjugate CaCO3 PSS-HRP was entrapped in chitosan based sol-gel(CS-GPTMS) film,HRP was encapsulated by in situ formation of an outer layer of AuNPs through electrochemical reduction of HAuCl4.The composite film containing AuNPs,CaCO3-PSS-HRP bioconjugates and CS-GPTMS can provide favorable microenvironment for HRP to perform direct electron transfer at glassy carbon electrode(GCE).HRP retained its bioelectrocatalytic activity and lead to sensitive and fast amperometric response for the determination of H2O2.H2O2 could be detected in a very wide linear range from 5.0× 10-6 mol/L to 7.1× 10-2 mol/L.The sandwich configuration of CaCO3-biomolecules-AuNPs could serve as a versatile platform for enzyme immobilization and biosensing.

  10. Steady-state equation of water vapor sorption for CaCl2-based chemical sorbents and its application

    Science.gov (United States)

    Zhang, Haiquan; Yuan, Yanping; Sun, Qingrong; Cao, Xiaoling; Sun, Liangliang

    2016-09-01

    Green CaCl2-based chemical sorbent has been widely used in sorption refrigeration, air purification and air desiccation. Methods to improve the sorption rate have been extensively investigated, but the corresponding theoretical formulations have not been reported. In this paper, a sorption system of solid-liquid coexistence is established based on the hypothesis of steady-state sorption. The combination of theoretical analysis and experimental results indicates that the system can be described by steady-state sorption process. The steady-state sorption equation, μ = (η - γT) , was obtained in consideration of humidity, temperature and the surface area. Based on engineering applications and this equation, two methods including an increase of specific surface area and adjustment of the critical relative humidity (γ) for chemical sorbents, have been proposed to increase the sorption rate. The results indicate that the CaCl2/CNTs composite with a large specific surface area can be obtained by coating CaCl2 powder on the surface of carbon nanotubes (CNTs). The composite reached sorption equilibrium within only 4 h, and the sorption capacity was improved by 75% compared with pure CaCl2 powder. Furthermore, the addition of NaCl powder to saturated CaCl2 solution could significantly lower the solution’s γ. The sorption rate was improved by 30% under the same environment.

  11. Steady-state equation of water vapor sorption for CaCl2-based chemical sorbents and its application

    Science.gov (United States)

    Zhang, Haiquan; Yuan, Yanping; Sun, Qingrong; Cao, Xiaoling; Sun, Liangliang

    2016-01-01

    Green CaCl2-based chemical sorbent has been widely used in sorption refrigeration, air purification and air desiccation. Methods to improve the sorption rate have been extensively investigated, but the corresponding theoretical formulations have not been reported. In this paper, a sorption system of solid-liquid coexistence is established based on the hypothesis of steady-state sorption. The combination of theoretical analysis and experimental results indicates that the system can be described by steady-state sorption process. The steady-state sorption equation, μ = (η − γT) , was obtained in consideration of humidity, temperature and the surface area. Based on engineering applications and this equation, two methods including an increase of specific surface area and adjustment of the critical relative humidity (γ) for chemical sorbents, have been proposed to increase the sorption rate. The results indicate that the CaCl2/CNTs composite with a large specific surface area can be obtained by coating CaCl2 powder on the surface of carbon nanotubes (CNTs). The composite reached sorption equilibrium within only 4 h, and the sorption capacity was improved by 75% compared with pure CaCl2 powder. Furthermore, the addition of NaCl powder to saturated CaCl2 solution could significantly lower the solution’s γ. The sorption rate was improved by 30% under the same environment. PMID:27682811

  12. Research on Cutting Force of Turn-Milling Based on Thin-Walled Blade

    Directory of Open Access Journals (Sweden)

    Lida Zhu

    2016-01-01

    Full Text Available Turn-milling is regarded as the milling of a curved surface while rotating the workpiece around its center point, which combines effectively the advantages of both turning and milling, wherein it allows for good metal removal with the difficult-to-cut thin-walled workpieces in aviation. The objective of the present work is to study cutting force by turn-milling in cutting condition. Aiming at the deformation properties of thin-walled blade, the predicted models of rigid cutting force and flexible cutting force with ball cutter are provided, respectively, in turn-milling process. The deformation values of blade and cutter are calculated, respectively, based on the engaged trajectory by using the iterative algorithm. The rigid and flexible cutting forces are compared and the influence degrees of cutting parameters on cutting forces are analyzed. These conclusions provide theoretical foundation and reference for turn-milling mechanism research.

  13. Research on spatial state conversion rule mining and stochastic predicting based on CA

    Science.gov (United States)

    Li, Xinyun; Kong, Xiangqiang

    2007-06-01

    Spatial dynamic prediction in GIS is the process of spatial calculation that infers the thematic maps in future according to the historical thematic maps, and it is space-time calculation from map to map. There is great application value that spatial dynamic prediction applied to the land planning, urban land-use planning and town planning, but there is some imperfect in method and technique at present. The main technical difficulty is excavation and expression of spatial state conversion rule. In allusion to the deficiency in spatial dynamic prediction using CA, the method which excavated spatial state conversion rule based on spatial data mining was put forward. Stochastic simulation mechanism was put into the prediction calculating based on state conversion rule. The result of prediction was more rational and the relation between the prediction steps and the time course was clearer. The method was applied to prediction of spatial structure change of urban land-use in Jinan. The Urban land-use change maps were predicted in 2006 and 2010 by using the land-use maps in 1998 and 2002. The result of this test was rational by analyzing.

  14. Discrimination Between Cervical Cancer Cells and Normal Cervical Cells Based on Longitudinal Elasticity Using Atomic Force Microscopy

    Science.gov (United States)

    Zhao, Xueqin; Zhong, Yunxin; Ye, Ting; Wang, Dajing; Mao, Bingwei

    2015-12-01

    The mechanical properties of cells are considered promising biomarkers for the early diagnosis of cancer. Recently, atomic force microscopy (AFM)-based nanoindentation technology has been utilized for the examination of cell cortex mechanics in order to distinguish malignant cells from normal cells. However, few attempts to evaluate the biomechanical properties of cells have focused on the quantification of the non-homogeneous longitudinal elasticity of cellular structures. In the present study, we applied a variation of the method of Carl and Schillers to investigate the differences between longitudinal elasticity of human cervical squamous carcinoma cells (CaSki) and normal cervical epithelial cells (CRL2614) using AFM. The results reveal a three-layer heterogeneous structure in the probing volume of both cell types studied. CaSki cells exhibited a lower whole-cell stiffness and a softer nuclei zone compared to the normal counterpart cells. Moreover, a better differentiated cytoskeleton was found in the inner cytoplasm/nuclei zone of the normal CRL2614 cells, whereas a deeper cytoskeletal distribution was observed in the probing volume of the cancerous counterparts. The sensitive cortical panel of CaSki cells, with a modulus of 0.35~0.47 kPa, was located at 237~225 nm; in normal cells, the elasticity was 1.20~1.32 kPa at 113~128 nm. The present improved method may be validated using the conventional Hertz-Sneddon method, which is widely reported in the literature. In conclusion, our results enable the quantification of the heterogeneous longitudinal elasticity of cancer cells, in particular the correlation with the corresponding depth. Preliminary results indicate that our method may potentially be applied to improve the detection of cancerous cells and provide insights into the pathophysiology of the disease.

  15. Surface engineering of a Zr-based bulk metallic glass with low energy Ar- or Ca-ion implantation.

    Science.gov (United States)

    Huang, Lu; Zhu, Chao; Muntele, Claudiu I; Zhang, Tao; Liaw, Peter K; He, Wei

    2015-02-01

    In the present study, low energy ion implantation was employed to engineer the surface of a Zr-based bulk metallic glass (BMG), aiming at improving the biocompatibility and imparting bioactivity to the surface. Ca- or Ar-ions were implanted at 10 or 50 keV at a fluence of 8 × 10(15)ions/cm(2) to (Zr0.55Al0.10Ni0.05Cu0.30)99Y1 (at.%) BMG. The effects of ion implantation on material properties and subsequent cellular responses were investigated. Both Ar- and Ca-ion implantations were suggested to induce atom displacements on the surfaces according to the Monte-Carlo simulation. The change of atomic environment of Zr in the surface regions as implied by the alteration in X-ray absorption measurements at Zr K-edge. X-ray photoelectron spectroscopy revealed that the ion implantation process has modified the surface chemical compositions and indicated the presence of Ca after Ca-ion implantation. The surface nanohardness has been enhanced by implantation of either ion species, with Ca-ion implantation showing more prominent effect. The BMG surfaces were altered to be more hydrophobic after ion implantation, which can be attributed to the reduced amount of hydroxyl groups on the implanted surfaces. Higher numbers of adherent cells were found on Ar- and Ca-ion implanted samples, while more pronounced cell adhesion was observed on Ca-ion implanted substrates. The low energy ion implantation resulted in concurrent modifications in atomic structure, nanohardness, surface chemistry, hydrophobicity, and cell behavior on the surface of the Zr-based BMG, which were proposed to be mutually correlated with each other. Published by Elsevier B.V.

  16. Environmental Assessment: Multiple Projects at Laughlin Air Force Base, Texas

    Science.gov (United States)

    2006-05-17

    feet from the source. Assuming that noise from the heavy equipment radiates equally in all directions, the sound intensity diminishes inversely as the...Publico sobre el La Evaluation de lmpacto Ambiental de MUltiples Proyectos en Ia Base de Ia Fuerza Aerea Laughlin De acuerdo con el Acta Nacional de 1

  17. Vibrational analysis of ferrocyanide complex ion based on density functional force field

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sun Kyung; Lee, Choong Keun; Lee, Nam Soo [Chungbuk National Univ., Cheongju (Korea, Republic of); Lee, Sang Ho [The University of Michigan, Ann Arbor (United States)

    2002-02-01

    Vibrational properties of ferrocyanide complex ion, [Fe(CN){sub 6}]{sup 4-}, have been studied based on the force constants obtained from the density functional calculations at B3LYP/6-31G level by means of the normal mode analysis using new bond angle and linear angle internal coordinates recently developed. Vibrations of ferrocyanide were manipulated by twenty-three symmetry force constants. The angled bending deformations of C-Fe-C, the linear bending deformations of Fe-C{identical_to}N and the stretching vibrations of Fe-C have been quantitatively assigned to the calculated frequencies. The force constants in the internal coordinates employed in the modified Urey-Bradley type potential were evaluated on the density functional force field applied, and better interaction force constants in the internal coordinates have been proposed. The valence force constants in the general quadratic valence force field were also given. The stretch-stretch interaction and stretch-bending interaction constants are not sensitive to the geometrical displacement in the valence force field.

  18. FORCE FEEDBACK MODEL OF ELECTRO-HYDRAULIC SERVO TELE-OPERATION ROBOT BASED ON VELOCITY CONTROL

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The tele-operation robotic system which consists of an excavator as the construction robot, and two joysticks for operating the robot from a safe place are useful for performing restoration in damaged areas. In order to accomplish a precise task, the operator needs to feel a realistic sense of task force brought about from a feedback force between the fork glove of slave robot and unfamiliar environment. A novel force feedback model is proposed based on velocity control of cylinder to determine environment force acting" on fork glove. Namely, the feedback force is formed by the error of displacement of joystick with velocity and driving force of piston, and the gain is calculated by the driving force and threshold of driving force of hydraulic cylinder. Moreover, the variable gain improved algorithm is developed to overcome the defect for grasping soft object. Experimental results for fork glove freedom of robotic system are provided to demonstrate the developed algorithm is available for grasping soft object.

  19. Flood-prone areas and waterways, Edwards Air Force Base, California

    Science.gov (United States)

    Meyer, Robert W.; Bowers, James C.

    2002-01-01

    Edwards Air Force Base (EAFB) is in the Mojave Desert region of southern California. Although the climate in the study area is arid, occasional intense storms result in flooding on the base, damaging roads and buildings. To plan for anticipated development at EAFB, the U.S. Department of the Air Force (USAF) and the U.S. Geological Survey (USGS) began a cooperative study to locate flood-prone areas on the base. This report describes flood hazards and shows flood-prone areas of the base.

  20. Design and Sensitivity Analysis Simulation of a Novel 3D Force Sensor Based on a Parallel Mechanism

    Directory of Open Access Journals (Sweden)

    Eileen Chih-Ying Yang

    2016-12-01

    Full Text Available Automated force measurement is one of the most important technologies in realizing intelligent automation systems. However, while many methods are available for micro-force sensing, measuring large three-dimensional (3D forces and loads remains a significant challenge. Accordingly, the present study proposes a novel 3D force sensor based on a parallel mechanism. The transformation function and sensitivity index of the proposed sensor are analytically derived. The simulation results show that the sensor has a larger effective measuring capability than traditional force sensors. Moreover, the sensor has a greater measurement sensitivity for horizontal forces than for vertical forces over most of the measurable force region. In other words, compared to traditional force sensors, the proposed sensor is more sensitive to shear forces than normal forces.

  1. Diverse Communications Project at Vandenberg Air Force Base

    Science.gov (United States)

    2008-07-25

    genetic variation, high variability in age and sex ratios , demographic stochasticity, and other random, naturally occurring events such as droughts or...modification, predation by introduced fish, bullfrogs, and feral pigs, and a loss of prey food base, particularly amphibians and fish. Unarmored...biologist(s) must follow the Declining Amphibian Population Task Force’s Code of Practice. • A USFWS approved biologist(s) must conduct a

  2. Peterson Air Force Base Transportation Plan Final Environmental Assessment

    Science.gov (United States)

    2013-03-01

    migratory transient Whooping Crane Grus Americana FE, SE No permanent habitat on Base but may migrate through area Western Burrowing owl Athene...burrowing owl (Athene cunicularia), and the ferruginous hawk (Buteo regalis). The mountain plover (Charadrius montanus) is found in nearby southern and...3.6.1 Noise Descriptors The decibel (dB) is the unit used to quantify the intensity of sound throughout all frequencies. However, the human ear

  3. Prestress Force Identification for Externally Prestressed Concrete Beam Based on Frequency Equation and Measured Frequencies

    Directory of Open Access Journals (Sweden)

    Luning Shi

    2014-01-01

    Full Text Available A prestress force identification method for externally prestressed concrete uniform beam based on the frequency equation and the measured frequencies is developed. For the purpose of the prestress force identification accuracy, we first look for the appropriate method to solve the free vibration equation of externally prestressed concrete beam and then combine the measured frequencies with frequency equation to identify the prestress force. To obtain the exact solution of the free vibration equation of multispan externally prestressed concrete beam, an analytical model of externally prestressed concrete beam is set up based on the Bernoulli-Euler beam theory and the function relation between prestress variation and vibration displacement is built. The multispan externally prestressed concrete beam is taken as the multiple single-span beams which must meet the bending moment and rotation angle boundary conditions, the free vibration equation is solved using sublevel simultaneous method and the semi-analytical solution of the free vibration equation which considered the influence of prestress on section rigidity and beam length is obtained. Taking simply supported concrete beam and two-span concrete beam with external tendons as examples, frequency function curves are obtained with the measured frequencies into it and the prestress force can be identified using the abscissa of the crosspoint of frequency functions. Identification value of the prestress force is in good agreement with the test results. The method can accurately identify prestress force of externally prestressed concrete beam and trace the trend of effective prestress force.

  4. Development of novel and sensitive sensors based on microcantilever of atomic force microscope

    Institute of Scientific and Technical Information of China (English)

    JIN Yan; WANG Kemin; JIN Rong

    2006-01-01

    Recently, the development of sensors based on microfabricated cantilevers of atomic force microscope (AFM) has attracted considerable attention from the designers of novel physical, chemical, and biological sensors. Many kinds of sensors have been developed taking the advantages of its high-resolution imaging, force measurement and force sensitivity, such as immunosensor and DNA biosensor and the sensors for detection of intermolecular interaction. This paper reviews the progress made in this field and discusses the signal transfer principles by which the design of the sensors is achieved.

  5. Hysteresis Compensation of Piezoresistive Carbon Nanotube/Polydimethylsiloxane Composite-Based Force Sensors.

    Science.gov (United States)

    Kim, Ji-Sik; Kim, Gi-Woo

    2017-01-24

    This paper provides a preliminary study on the hysteresis compensation of a piezoresistive silicon-based polymer composite, poly(dimethylsiloxane) dispersed with carbon nanotubes (CNTs), to demonstrate its feasibility as a conductive composite (i.e., a force-sensitive resistor) for force sensors. In this study, the potential use of the nanotube/polydimethylsiloxane (CNT/PDMS) as a force sensor is evaluated for the first time. The experimental results show that the electrical resistance of the CNT/PDMS composite changes in response to sinusoidal loading and static compressive load. The compensated output based on the Duhem hysteresis model shows a linear relationship. This simple hysteresis model can compensate for the nonlinear frequency-dependent hysteresis phenomenon when a dynamic sinusoidal force input is applied.

  6. Hysteresis Compensation of Piezoresistive Carbon Nanotube/Polydimethylsiloxane Composite-Based Force Sensors

    Directory of Open Access Journals (Sweden)

    Ji-Sik Kim

    2017-01-01

    Full Text Available This paper provides a preliminary study on the hysteresis compensation of a piezoresistive silicon-based polymer composite, poly(dimethylsiloxane dispersed with carbon nanotubes (CNTs, to demonstrate its feasibility as a conductive composite (i.e., a force-sensitive resistor for force sensors. In this study, the potential use of the nanotube/polydimethylsiloxane (CNT/PDMS as a force sensor is evaluated for the first time. The experimental results show that the electrical resistance of the CNT/PDMS composite changes in response to sinusoidal loading and static compressive load. The compensated output based on the Duhem hysteresis model shows a linear relationship. This simple hysteresis model can compensate for the nonlinear frequency-dependent hysteresis phenomenon when a dynamic sinusoidal force input is applied.

  7. Preparation of TiFe based alloys melted by CaO crucible and its hydrogen storage properties

    Energy Technology Data Exchange (ETDEWEB)

    Li, Chong-he, E-mail: chli@staff.shu.edu.cn [Shanghai Key Laboratory of Modern Metallurgy and Materials Processing, Shanghai University, Shanghai 200072 (China); Shanghai Special Casting Engineering Technology Research Center, Shanghai 201605 (China); He, Jin; Zhang, Zhao; Yang, Bo; Leng, Hai-yan [Shanghai Key Laboratory of Modern Metallurgy and Materials Processing, Shanghai University, Shanghai 200072 (China); Lu, Xiong-gang, E-mail: luxg@staff.shu.edu.cn [Shanghai Key Laboratory of Modern Metallurgy and Materials Processing, Shanghai University, Shanghai 200072 (China); Shanghai Special Casting Engineering Technology Research Center, Shanghai 201605 (China); Li, Zhi-lin; Wu, Zhu [Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Wang, Hong-bin [Shanghai Key Laboratory of Modern Metallurgy and Materials Processing, Shanghai University, Shanghai 200072 (China); Shanghai Special Casting Engineering Technology Research Center, Shanghai 201605 (China)

    2015-01-05

    Highlights: • The home-made CaO crucible was used to prepare the TiFe based alloys. • The compositions as well as the content of oxygen can be effectively controlled. • The microstructure of the alloy melted by CaO crucible is dendrite. • The samples performed a good hydrogen storage performance. • The CaO crucible may be the promising candidate for melting the TiFe based alloys. - Abstract: The carbon contamination of alloys prepared by the electro graphite crucible is impossible to avoid due to the inherit reaction between the melt and the crucible. In this study, the TiFe-based alloy is prepared by VIM process using CaO crucible as well as the electro graphite crucible. The samples are examined by means of Optical Microscopy (OM), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Energy Dispersive Spectrometer (EDS), and the PCT curves are also measured. It is resulted that, the oxygen content of alloys melted by CaO crucible is almost equal to the one melted by graphite crucible and without the carbon contamination, meanwhile the carbon content of alloys obtained by the electro graphite crucible is 1860 ppm, which exceeds the tolerance of the commercial alloy (1000 ppm). The microstructure of the alloy melted by CaO crucible is dendrite, while it is composed of the equiaxed crystal with the lamellar structure and the spherical TiC particles distributed along grain boundaries or within the grain when melted by the graphite crucible; the interfacial reaction of the electro graphite crucible with TiFe alloy melt is serious and the interaction layer is formed up to 200 μm in thickness, the carbon in TiFe-based alloys forms TiC. The hydrogen desorption plateau pressure of alloys melted by CaO crucible is (0.11–0.4) × 10{sup 5} Pa, and that by the graphite crucible is (0.6–1) × 10{sup 5} Pa. This may imply that the CaO crucible may be the promising candidate for melting the high performance TiFe based hydrogen storage alloys.

  8. Environmental Assessment: Proposed Photovoltaic Array, Hill Air Force Base, Utah

    Science.gov (United States)

    2008-08-28

    AFB tree removal and replacement plan (Hill 2006). The tree replacement policy is based on each tree’s diameter at breast height ( DBH ). For example...if a tree with a DBH of 10 inches was removed, it would be replaced with 10 trees each with a one-inch DBH , or any combination of trees equivalent...would not create solid or hazardous waste. Biological No effects Attempts to preserve trees could be unsuccessfuL Up to 62 trees could be Resources

  9. Methods of improving mechanical and biomedical properties of Ca-Si-based ceramics and scaffolds.

    Science.gov (United States)

    Wu, Chengtie

    2009-05-01

    CaSiO3 ceramics and porous scaffolds are regarded as potential materials for bone tissue regeneration owing to their excellent bioactivity. However, their low mechanical strength and high dissolution limit their further biomedical application. In this report, we introduce three methods to improve the mechanical and biomedical properties of CaSiO3 ceramics and scaffolds. Positive ions and polymer modification are two promising ways to improve the mechanical and biomedical properties of CaSiO3 ceramics and scaffolds for bone tissue regeneration.

  10. EMG-to-force estimation with full-scale physiology based muscle model

    OpenAIRE

    Hayashibe, Mitsuhiro; Guiraud, David; Poignet, Philippe

    2009-01-01

    International audience; EMG-to-force estimation for voluntary muscle contraction has many applications in human-machine interaction, motion analysis, and rehabilitation robotics for prosthetic limbs or exoskeletons. EMG-based model can account for a subject's individual activation patterns to estimate muscle force. For the estimation, so-called Hill-type model has been used in most of the cases. It already has shown its promising performance, but it is still known as a phenomenological model ...

  11. CaSePer: An efficient model for personalized web page change detection based on segmentation

    Directory of Open Access Journals (Sweden)

    K.S. Kuppusamy

    2014-01-01

    Full Text Available Users who visit a web page repeatedly at frequent intervals are more interested in knowing the recent changes that have occurred on the page than the entire contents of the web page. Because of the increased dynamism of web pages, it would be difficult for the user to identify the changes manually. This paper proposes an enhanced model for detecting changes in the pages, which is called CaSePer (Change detection based on Segmentation with Personalization. The change detection is micro-managed by introducing web page segmentation. The web page change detection process is made efficient by having it perform a dual-step process. The proposed method reduces the complexity of the change-detection by focusing only on the segments in which the changes have occurred. The user-specific personalized change detection is also incorporated in the proposed model. The model is validated with the help of a prototype implementation. The experiments conducted on the prototype implementation confirm a 77.8% improvement and a 97.45% accuracy rate.

  12. Rate-based modelling and validation of a pilot absorber using MDEA enhanced with carbonic anhydrase (CA)

    DEFF Research Database (Denmark)

    Gaspar, Jozsef; Gladis, Arne; Woodley, John

    2017-01-01

    solvent-regeneration energy demand.The focus of this work is to develop a rate-based model for CO2 absorption using MDEA enhanced with CA and to validate it against pilot-scale absorption experiments. In this work, we compare model predictions to measured temperature and CO2 concentration profiles...

  13. Mechanical activation of CaO-based adsorbents for CO(2) capture.

    Science.gov (United States)

    Sayyah, Maryam; Lu, Yongqi; Masel, Richard I; Suslick, Kenneth S

    2013-01-01

    The reversible cycling of CaO adsorbents to CaCO(3) for high-temperature CO(2) capture is substantially improved by mechanical treatment. The mechanical milling intensity and conditions of grinding (e.g., wet vs. dry, planetary vs. vibratory milling) were determined to be the main factors that control the effectiveness of the mechanochemical synthesis to enhance the recycling stability of the sorbents prepared. In addition, MgO was used as an example of an inert binder to help mitigate CaCO(3) sintering. Wet planetary milling of MgO into CaCO(3) allowed efficient particle size reduction and the effective dispersion of MgO throughout the particles. Wet planetary milling yielded the most stable sorbents during 50 cycles of carbonation-calcination.

  14. Microscopic evidence for Ca(2+) mediated pectin-pectin interactions in carrot-based suspensions.

    Science.gov (United States)

    Kyomugasho, Clare; Willemsen, Katleen L D D; Christiaens, Stefanie; Van Loey, Ann M; Hendrickx, Marc E

    2015-12-01

    This study explored the use of fluorescently labeled pectin to obtain evidence for Ca(2+) mediated pectin-pectin interactions in situ. Specifically, carrots were either blanched at low temperature (LTB) or blanched at high temperature (HTB) to activate or inactivate endogenous pectin methylesterase, respectively. Consequently, pectin in tissue particles of LTB and HTB carrots exhibited low degree of methylesterification (DM) and high DM, respectively. Pectin present in the LTB carrot serum exhibited a lower DM, was more branched, and showed a higher molar mass compared to HTB carrot serum pectin. Ca(2+) mediated pectin-pectin interactions were influenced by serum pectin molecular structure, increased with increasing pH and Ca(2+) concentration, and decreasing DM. Presence of more linear pectin in the serum created a competition, leading to less intense interactions between labeled pectin and pectin at tissue particle surfaces. Generally, the most intense Ca(2+) mediated pectin-pectin interactions were observed for pectin of LTB carrot particles.

  15. A neutron scintillator based on transparent nanocrystalline CaF{sub 2}:Eu glass ceramic

    Energy Technology Data Exchange (ETDEWEB)

    Struebing, Christian; Kang, Zhitao, E-mail: zhitao.kang@gtri.gatech.edu [Georgia Tech Research Institute, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Chong, JooYun; Wagner, Brent [Georgia Tech Research Institute, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Lee, Gyuhyon; Ding, Yong [School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Zavala, Martin; Erickson, Anna [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Wang, Cai-Lin; Diawara, Yacouba [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6460 (United States); Engels, Ralf [Forschungszentrum Jülich GmbH, Jülich 52425 (Germany)

    2016-04-11

    There are no efficient Eu{sup 2+} doped glass neutron scintillators reported due to low doping concentrations of Eu{sup 2+} and the amorphous nature of the glass matrix. In this work, an efficient CaF{sub 2}:Eu glass ceramic neutron scintillator was prepared by forming CaF{sub 2}:Eu nanocrystals in a {sup 6}Li-containing glass matrix. Through appropriate thermal treatments, the scintillation light yield of the transparent glass ceramic was increased by a factor of at least 46 compared to the as-cast amorphous glass. This improvement was attributed to more efficient energy transfer from the CaF{sub 2} crystals to the Eu{sup 2+} emitting centers. Further light yield improvement is expected if the refractive index of the glass matrix can be matched to the CaF{sub 2} crystal.

  16. Detecting and Reducing Science Teacher Candidate’s (STC) Misconception About Motion and Force By Using Force Concept Inventory (FCI) and problem Based Learning (PBL)

    Science.gov (United States)

    Oktarisa, Y.; Utami, I. S.; Denny, Y. R.

    2017-02-01

    This study has been done to 34 science teacher candidates of Teachers’ Training and Education Faculty of Sultan Ageng Tirtayasa University at their first year of study during 2015-2016 school years. This research focused on student’s misconception about motion and force and how Problem Based Learning (PBL) reducing it. Diagnostic test of misconception about motion and force has been detected by using Force Concept Inventory (FCI). FCI had been used in pretest and posttest, and to find the reducing of students’ misconception N-Gain pretest and posttest of each student had been calculated. Quasi experiment one group pretest and posttest had been used as the research method, and Problem Based Learning (PBL) used as the treatment of manipulation. After two weeks learning motion and force with PBL approach, N-gain which obtained prove that misconception about motion and force had been reducing.

  17. CaGrid workflow toolkit: A taverna based workflow tool for cancer grid

    OpenAIRE

    Sulakhe Dinanath; Soiland-Reyes Stian; Nenadic Alexandra; Madduri Ravi; Tan Wei; Foster Ian; Goble Carole A

    2010-01-01

    Abstract Background In biological and medical domain, the use of web services made the data and computation functionality accessible in a unified manner, which helped automate the data pipeline that was previously performed manually. Workflow technology is widely used in the orchestration of multiple services to facilitate in-silico research. Cancer Biomedical Informatics Grid (caBIG) is an information network enabling the sharing of cancer research related resources and caGrid is its underly...

  18. Study on Ferroelectric and Dielectric Properties of La-Doped CaBi4Ti4O15-Based Ceramics

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Lanthanum doped bismuth layer structured ferroelectrics (BLSFs) Ca1-xLaxBi4(Ti0.9W0.1)4O15 (x=0, 0.2, 0.3, 0.4, 0.6) ceramics were prepared by solid-state reaction method. X-ray diffraction(XRD) patterns showed that single phase was formed when x=0~0.6. The effects of La3+ doping on dielectric, piezoelectric and ferroelectric properties of Ca1-xLaxBi4(Ti0.9W0.1)4O15 ceramics were studied. Ca0.7La0.3Bi4(Ti0.9W0.1)4O15 ceramic had optimal properties, its dielectric constant was 166.85, dielectric loss was 0.0063, piezoelectric strain constant was 11 pc·N-1, remanent polarization was 18.1 μC·cm-2 and coercive field was 118 kV·cm-1. SEM micrographs showed that the grains of CaBi4Ti4O15-based ceramics were plate-like. The results of energy spectrum analysis (EDS) showed that La3+ incorporation could increase Bi/Ca ratio.

  19. A Vision-Based Approach for Estimating Contact Forces: Applications to Robot-Assisted Surgery

    Directory of Open Access Journals (Sweden)

    C. W. Kennedy

    2005-01-01

    Full Text Available The primary goal of this paper is to provide force feedback to the user using vision-based techniques. The approach presented in this paper can be used to provide force feedback to the surgeon for robot-assisted procedures. As proof of concept, we have developed a linear elastic finite element model (FEM of a rubber membrane whereby the nodal displacements of the membrane points are measured using vision. These nodal displacements are the input into our finite element model. In the first experiment, we track the deformation of the membrane in real-time through stereovision and compare it with the actual deformation computed through forward kinematics of the robot arm. On the basis of accurate deformation estimation through vision, we test the physical model of a membrane developed through finite element techniques. The FEM model accurately reflects the interaction forces on the user console when the interaction forces of the robot arm with the membrane are compared with those experienced by the surgeon on the console through the force feedback device. In the second experiment, the PHANToM haptic interface device is used to control the Mitsubishi PA-10 robot arm and interact with the membrane in real-time. Image data obtained through vision of the deformation of the membrane is used as the displacement input for the FEM model to compute the local interaction forces which are then displayed on the user console for providing force feedback and hence closing the loop.

  20. Distributed forcing of the flow past a blunt-based axisymmetric bluff body

    Science.gov (United States)

    Jardin, Thierry; Bury, Yannick

    2014-06-01

    In this paper, we address the influence of a blowing-/suction-type distributed forcing on the flow past a blunt-based axisymmetric bluff body by means of direct numerical simulations. The forcing is applied via consecutive blowing and suction slots azimuthally distributed along the trailing edge of the bluff body. We examine the impact of the forcing wavelength, amplitude and waveform on the drag experienced by the bluff body and on the occurrence of the reflectional symmetry preserving and reflectional symmetry breaking wake modes, for Reynolds numbers 800 and 1,000. We show that forcing the flow at wavelengths inherent to the unforced flow drastically damps drag oscillations associated with the vortex shedding and vorticity bursts, up to their complete suppression. The overall parameter analysis suggests that this damping results from the surplus of streamwise vorticity provided by the forcing that tends to stabilize the ternary vorticity lobes observed at the aft part of the bluff body. In addition, conversely to a blowing-type or suction-type forcing, the blowing-/suction-type forcing involves strong nonlinear interactions between locally decelerated and accelerated regions, severely affecting both the mean drag and the frequencies representative of the vortex shedding and vorticity bursts.

  1. Force-based optimization of pseudopotentials for non-equilibrium configurations

    Science.gov (United States)

    Brock, Casey N.; Paikoff, Brandon C.; Md Sallih, Muhammad I.; Tackett, Alan R.; Walker, D. Greg

    2016-04-01

    We have used a multi-objective genetic algorithm to optimize pseudopotentials for force accuracy and computational efficiency. Force accuracy is determined by comparing interatomic forces generated using the pseudopotentials and forces generated using the full-potential linearized augmented-plane wave method. This force-based optimization approach is motivated by applications where interatomic forces are important, including material interfaces, crystal defects, and molecular dynamics. Our method generates Pareto sets of optimized pseudopotentials containing various compromises between accuracy and efficiency. We have tested our method for LiF, Si0.5Ge0.5, and Mo and compared the performance of our pseudopotentials with pseudopotentials available from the ABINIT library. We show that the optimization can generate pseudopotentials with comparable accuracy (in terms of force matching and equation of state) to pseudopotentials in the literature while sometimes significantly improving computational efficiency. For example, we generated pseudopotentials for one system tested that reduced computational work by 71% without loss of accuracy. These results suggest our method can be used to generate pseudopotentials on demand that are tuned for a user's specific application, affording gains in computational efficiency.

  2. Experimental study of frost heaving force based on transient shock response using piezoceramic sensors

    Science.gov (United States)

    Wang, Ruolin; Peng, Tongxiao; Wang, Ming L.

    2016-04-01

    In seasonally frozen soil regions, the frost heaving problem made it difficult to monitor or evaluate the pile safety for long term. So far, no mature tool can be utilized to monitor the frost heaving force, which was unevenly distributed along the pile. In this paper, a piezoceramic sensing based transient excitation response approach was proposed to monitor the frost heaving force in real time. Freeze-thaw cycles can result in great changes of soil engineering properties, including the frost heaving force. So, the freeze-thaw cycle was repeated fourth to study its effect. In the experiment, transient horizontal shock on the top of the pile will be detected by the 6 PZT sensors glued on the pile. The signal data received by the 6 PZT sensors can be used to illustrate the frost heaving force distribution along the pile. Moisture content effect is also one of the important reasons that cause the variation of soil mechanical properties. So three different moisture content (6%, 12%, 18%) testing soil were used in this experiment to detect the variance of the frost heaving force. An energy indicator was developed to quantitatively evaluate the frost heaving force applied on the pile. The experimental results showed that the proposed method was effective in monitoring the uneven distribution of frost heaving force along the pile.

  3. Comparison of an EMG-based and a stress-based method to predict shoulder muscle forces.

    Science.gov (United States)

    Engelhardt, Christoph; Malfroy Camine, Valérie; Ingram, David; Müllhaupt, Philippe; Farron, Alain; Pioletti, Dominique; Terrier, Alexandre

    2015-01-01

    The estimation of muscle forces in musculoskeletal shoulder models is still controversial. Two different methods are widely used to solve the indeterminacy of the system: electromyography (EMG)-based methods and stress-based methods. The goal of this work was to evaluate the influence of these two methods on the prediction of muscle forces, glenohumeral load and joint stability after total shoulder arthroplasty. An EMG-based and a stress-based method were implemented into the same musculoskeletal shoulder model. The model replicated the glenohumeral joint after total shoulder arthroplasty. It contained the scapula, the humerus, the joint prosthesis, the rotator cuff muscles supraspinatus, subscapularis and infraspinatus and the middle, anterior and posterior deltoid muscles. A movement of abduction was simulated in the plane of the scapula. The EMG-based method replicated muscular activity of experimentally measured EMG. The stress-based method minimised a cost function based on muscle stresses. We compared muscle forces, joint reaction force, articular contact pressure and translation of the humeral head. The stress-based method predicted a lower force of the rotator cuff muscles. This was partly counter-balanced by a higher force of the middle part of the deltoid muscle. As a consequence, the stress-based method predicted a lower joint load (16% reduced) and a higher superior-inferior translation of the humeral head (increased by 1.2 mm). The EMG-based method has the advantage of replicating the observed cocontraction of stabilising muscles of the rotator cuff. This method is, however, limited to available EMG measurements. The stress-based method has thus an advantage of flexibility, but may overestimate glenohumeral subluxation.

  4. Design and Synthesis of Distillation Systems using a Driving Force Based Approach

    DEFF Research Database (Denmark)

    Bek-Pedersen, Erik; Gani, Rafiqul

    2004-01-01

    A new integrated framework for synthesis, design and operation of distillation-based separation schemes is presented here. This framework is based on the driving force approach, which provides a measure of the differences in chemical/physical properties between two co-existing phases in a separat...

  5. Installation Restoration Program, Phase II - Confirmation/Quantification Stage I, Moody Air Force Base, Georgia.

    Science.gov (United States)

    1985-12-01

    ABBREVIATIONS, AND UNITS OF MESUREMENT ~~(Page I of 2) "’ 2 % W. -* AFB Air Force Base ATC Air Training Command I ASTM American Society for Testing Materials...following emergency phone numbers should be available * 1 on-site: I. Ambulance or medical assistance, 2. Base fire department (or other if off-site), and

  6. Environmental Assessment for Proposed Utility Corridors at Edwards Air Force Base, California

    Science.gov (United States)

    2016-07-01

    Edwards Air Force Base, California CNPS California Native Plant Society CO Carbon monoxide CO2 Carbon dioxide CO2e Carbon dioxide equivalent mass ...corridors include existing easements, north-south and east-west traversing the Base and take into consideration current easements, communication ...73 3.7.3 Wildlife Communities

  7. Development of a quartz tuning-fork-based force sensor for measurements in the tens of nanoNewton force range during nanomanipulation experiments

    Energy Technology Data Exchange (ETDEWEB)

    Oiko, V. T. A., E-mail: oiko@ifi.unicamp.br; Rodrigues, V.; Ugarte, D. [Instituto de Física “Gleb Wataghin,” Univ. Estadual de Campinas (UNICAMP), Campinas 13083-859 (Brazil); Martins, B. V. C. [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2R3 (Canada); Silva, P. C. [Laboratório Nacional de Nanotecnologia, CNPEM, Campinas 13083-970 (Brazil)

    2014-03-15

    Understanding the mechanical properties of nanoscale systems requires new experimental and theoretical tools. In particular, force sensors compatible with nanomechanical testing experiments and with sensitivity in the nN range are required. Here, we report the development and testing of a tuning-fork-based force sensor for in situ nanomanipulation experiments inside a scanning electron microscope. The sensor uses a very simple design for the electronics and it allows the direct and quantitative force measurement in the 1–100 nN force range. The sensor response is initially calibrated against a nN range force standard, as, for example, a calibrated Atomic Force Microscopy cantilever; subsequently, applied force values can be directly derived using only the electric signals generated by the tuning fork. Using a homemade nanomanipulator, the quantitative force sensor has been used to analyze the mechanical deformation of multi-walled carbon nanotube bundles, where we analyzed forces in the 5–40 nN range, measured with an error bar of a few nN.

  8. Finite Element Method Based Modeling for Prediction of Cutting Forces in Micro-end Milling

    Science.gov (United States)

    Pratap, Tej; Patra, Karali

    2017-02-01

    Micro-end milling is one of the widely used processes for producing micro features/components in micro-fluidic systems, biomedical applications, aerospace applications, electronics and many more fields. However in these applications, the forces generated in the micro-end milling process can cause tool vibration, process instability and even cause tool breakage if not minimized. Therefore, an accurate prediction of cutting forces in micro-end milling is essential. In this work, a finite element method based model is developed using ABAQUS/Explicit 6.12 software for prediction of cutting forces in micro-end milling with due consideration of tool edge radius effect, thermo-mechanical properties and failure parameters of the workpiece material including friction behaviour at tool-chip interface. Experiments have been performed for manufacturing of microchannels on copper plate using 500 µm diameter tungsten carbide micro-end mill and cutting forces are acquired through a dynamometer. Predicted cutting forces in feed and cross feed directions are compared with experimental results and are found to be in good agreements. Results also show that FEM based simulations can be applied to analyze size effects of specific cutting forces in micro-end milling process.

  9. A Large Area Tactile Sensor Patch Based on Commercial Force Sensors

    Directory of Open Access Journals (Sweden)

    Alfonso García-Cerezo

    2011-05-01

    Full Text Available This paper reports the design of a tactile sensor patch to cover large areas of robots and machines that interact with human beings. Many devices have been proposed to meet such a demand. These realizations are mostly custom-built or developed in the lab. The sensor of this paper is implemented with commercial force sensors. This has the benefit of a more foreseeable response of the sensor if its behavior is understood as the aggregation of readings from all the individual force sensors in the array. A few reported large area tactile sensors are also based on commercial sensors. However, the one in this paper is the first of this kind based on the use of polymeric commercial force sensing resistors (FSR as unit elements of the array or tactels, which results in a robust sensor. The paper discusses design issues related to some necessary modifications of the force sensor, its assembly in an array, and the signal conditioning. The patch has 16 × 9 force sensors mounted on a flexible printed circuit board with a spatial resolution of 18.5 mm. The force range of a tactel is 6 N and its sensitivity is 0.6 V/N. The array is read at a rate of 78 frames per second. Finally, two simple application examples are also carried out with the sensor mounted on the forearm of a rescue robot that communicates with the sensor through a CAN bus.

  10. Multi-Axis Force/Torque Sensor Based on Simply-Supported Beam and Optoelectronics

    Science.gov (United States)

    Noh, Yohan; Bimbo, Joao; Sareh, Sina; Wurdemann, Helge; Fraś, Jan; Chathuranga, Damith Suresh; Liu, Hongbin; Housden, James; Althoefer, Kaspar; Rhode, Kawal

    2016-01-01

    This paper presents a multi-axis force/torque sensor based on simply-supported beam and optoelectronic technology. The sensor’s main advantages are: (1) Low power consumption; (2) low-level noise in comparison with conventional methods of force sensing (e.g., using strain gauges); (3) the ability to be embedded into different mechanical structures; (4) miniaturisation; (5) simple manufacture and customisation to fit a wide-range of robot systems; and (6) low-cost fabrication and assembly of sensor structure. For these reasons, the proposed multi-axis force/torque sensor can be used in a wide range of application areas including medical robotics, manufacturing, and areas involving human–robot interaction. This paper shows the application of our concept of a force/torque sensor to flexible continuum manipulators: A cylindrical MIS (Minimally Invasive Surgery) robot, and includes its design, fabrication, and evaluation tests. PMID:27869689

  11. Multi-Axis Force/Torque Sensor Based on Simply-Supported Beam and Optoelectronics.

    Science.gov (United States)

    Noh, Yohan; Bimbo, Joao; Sareh, Sina; Wurdemann, Helge; Fraś, Jan; Chathuranga, Damith Suresh; Liu, Hongbin; Housden, James; Althoefer, Kaspar; Rhode, Kawal

    2016-11-17

    This paper presents a multi-axis force/torque sensor based on simply-supported beam and optoelectronic technology. The sensor's main advantages are: (1) Low power consumption; (2) low-level noise in comparison with conventional methods of force sensing (e.g., using strain gauges); (3) the ability to be embedded into different mechanical structures; (4) miniaturisation; (5) simple manufacture and customisation to fit a wide-range of robot systems; and (6) low-cost fabrication and assembly of sensor structure. For these reasons, the proposed multi-axis force/torque sensor can be used in a wide range of application areas including medical robotics, manufacturing, and areas involving human-robot interaction. This paper shows the application of our concept of a force/torque sensor to flexible continuum manipulators: A cylindrical MIS (Minimally Invasive Surgery) robot, and includes its design, fabrication, and evaluation tests.

  12. The Simulation of the Brush Stroke Based on Force Feedback Technology

    Directory of Open Access Journals (Sweden)

    Chao Guo

    2015-01-01

    Full Text Available A novel simulation method of the brush stroke is proposed by applying force feedback technology to the virtual painting process. The relationship between force and the brush deformation is analyzed, and the spring-mass model is applied to construct the brush model, which can realistically simulate the brush morphological changes according to the force exerted on it. According to the deformation of the brush model at a sampling point, the brush footprint between the brush and the paper is calculated in real time. Then, the brush stroke is obtained by superimposing brush footprints along sampling points, and the dynamic painting of the brush stroke is implemented. The proposed method has been successfully applied to the virtual painting system based on the force feedback technology. In this system, users can implement the painting in real time with a Phantom Desktop haptic device, which can effectively enhance reality to users.

  13. Static force transducer based on resonant piezoelectric structure: root cause investigation

    Science.gov (United States)

    Safour, Salaheddine; Bernard, Yves

    2017-05-01

    The aim of this paper is to investigate the design and the integration of a static force sensor based on a resonant bulk acoustic wave piezoelectric transducer. Experimental measurements of the electrical admittance spectrum show its dependence on the applied force. We noticed that the quality of the frequency response for a given vibration mode degrades with the increase of the applied force, which limits the force measuring range. The root cause of the response-stress dependence is investigated by means of the developed analytical model and a finite element analysis. The analysis results show that the selected operating vibration mode, the components of the structure on which the piezoelectric specimen is positioned and the boundary conditions at the contact interfaces between all the components have a direct effect on the electrical admittance spectrum. A modified structure was proposed to enhance the quality of the frequency response. The experimental tests show higher measuring range (up to 1500 N).

  14. Multi-Axis Force/Torque Sensor Based on Simply-Supported Beam and Optoelectronics

    Directory of Open Access Journals (Sweden)

    Yohan Noh

    2016-11-01

    Full Text Available This paper presents a multi-axis force/torque sensor based on simply-supported beam and optoelectronic technology. The sensor’s main advantages are: (1 Low power consumption; (2 low-level noise in comparison with conventional methods of force sensing (e.g., using strain gauges; (3 the ability to be embedded into different mechanical structures; (4 miniaturisation; (5 simple manufacture and customisation to fit a wide-range of robot systems; and (6 low-cost fabrication and assembly of sensor structure. For these reasons, the proposed multi-axis force/torque sensor can be used in a wide range of application areas including medical robotics, manufacturing, and areas involving human–robot interaction. This paper shows the application of our concept of a force/torque sensor to flexible continuum manipulators: A cylindrical MIS (Minimally Invasive Surgery robot, and includes its design, fabrication, and evaluation tests.

  15. A computed torque method based attitude control with optimal force distribution for articulated body mobile robots

    Energy Technology Data Exchange (ETDEWEB)

    Fukushima, Edwardo F.; Hirose, Shigeo [Tokyo Inst. of Tech. (Japan)

    2000-05-01

    This paper introduces an attitude control scheme based in optimal force distribution using quadratic programming which minimizes joint energy consumption. This method shares similarities with force distribution for multifingered hands, multiple coordinated manipulators and legged walking robots. In particular, an attitude control scheme was introduced inside the force distribution problem, and successfully implemented for control of the articulated body mobile robot KR-II. This is an actual mobile robot composed of cylindrical segments linked in series by prismatic joints and has a long snake-like appearance. These prismatic joints are force controlled so that each segment's vertical motion can automatically follow the terrain irregularities. An attitude control is necessary because this system acts like a system of wheeled inverted pendulum carts connected in series, being unstable by nature. The validity and effectiveness of the proposed method is verified by computer simulation and experiments with the robot KR-II. (author)

  16. A New Method of Desired Gait Synthesis for Biped Walking Robot Based on Ground Reaction Force

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A new method of desired gait synthesis for biped walking robot based on the ground reaction force was proposed. The relation between the ground reaction force and joint motion is derived using the D'Almbert principle. In view of dynamic walking with high stability, the ZMP(Zero Moment Point)stability criterion must be considered in the desired gait synthesis. After that, the joint trajectories of biped walking robot are decided by substituting the ground reaction force into the aforesaid relation based on the ZMP criterion. The trajectory of desired ZMP is determined by a fuzzy logic based upon the body posture of biped walking robot. The proposed scheme is simulated and experimented on a 10 degree of freedom biped walking robot. The results indicate that the proposed method is feasible.

  17. Finite Element Based Stress Analysis of Seat Belt Using Integrated Force Method

    Directory of Open Access Journals (Sweden)

    Anjali Kale

    2014-06-01

    Full Text Available Integrated force method (IFM has been developed for solving various continuum mechanics problems, where all the internal forces are taken as independent variables. The system equilibrium equations (EE's are mathematically concatenated with the MATLAB based compatibility conditions (CC's to form the global set of equations. This paper explains the solution strategy of prototype seat-belt component using integrated force method. Actual seat belt component is taken here to verify IFM based FE element are readily used which is named as REC_5F_8D and REC_13F_16D where 5F and 13F reflects number of internal unknowns and 8D and 16D are number of total displacements respectively. The results for “Von Mises Stress” and Maximum Displacement using IFM based formulation and compared with ANSYS.

  18. Cadherin-Based Intercellular Adhesions Organize Epithelial Cell-Matrix Traction Forces

    CERN Document Server

    Mertz, Aaron F; Banerjee, Shiladitya; Goldstein, Jill; Rosowski, Kathryn R; Niessen, Carien M; Marchetti, M Cristina; Dufresne, Eric R; Horsley, Valerie

    2012-01-01

    Cell--cell and cell-matrix adhesions play essential roles in the function of tissues. There is growing evidence for the importance of crosstalk between these two adhesion types, yet little is known about the impact of these interactions on the mechanical coupling of cells to the extracellular-matrix (ECM). Here, we combine experiment and theory to reveal how intercellular adhesions modulate forces transmitted to the ECM. In the absence of cadherin-based adhesions, primary mouse keratinocytes within a colony appear to act independently, with significant traction forces extending throughout the colony. In contrast, with strong cadherin-based adhesions, keratinocytes in a cohesive colony localize traction forces to the colony periphery. Through genetic or antibody-mediated loss of cadherin expression or function, we show that cadherin-based adhesions are essential for this mechanical cooperativity. A minimal physical model in which cell--cell adhesions modulate the physical cohesion between contractile cells is ...

  19. Spatial information recognizing of ocean eddies based on virtual force field and its application

    Institute of Scientific and Technical Information of China (English)

    LI Ce; DU Yunyan; SU Fenzhen; YANG Xiaomei; XU Jun

    2007-01-01

    A new approach to detecting ocean eddies automatically from remote sensing imageries based on the ocean eddy's eigen-pattern in remote sensing imagery and "force field-based shape extracting method" is proposed. First, the analysis on extracting eddies' edges from remote sensing imagery using conventional edge detection arithmetic operators is performed and returns digitized vector edge data as a result. Second, attraction forces and fusion forces between edge curves were analyzed and calculated based on the vector eddy edges. Thirdly, the virtual significant spatial patterns of eddy were detected automatically using iterative repetition followed by optimized rule. Finally, the spatial form auto-detection of different types of ocean eddies was done using satellite images.The study verified that this is an effective way to identify and detect the ocean eddy with a complex form.

  20. Effect of Strong Basic Oxide (Li2O, Na2O, K2O and BaO) on Property of CaO-Based Flux

    Institute of Scientific and Technical Information of China (English)

    LI Gui-rong

    2003-01-01

    It is found that strong basic oxides including Li2O, Na2O, K2O and BaO, which are used to replace a part of CaO in CaO-based fluxes, can lower the melting point and the viscosity and enhance the dephosphorizing ability. The mechanism was analysed and the addition of Li2O to CaO-based fluxes was recommended.

  1. Determination of nitric oxide mediating intracellular Ca2+ release on neurons based on confocal microscopy imaging

    Science.gov (United States)

    Zheng, Liqin; Wang, Yuhua; He, Yipeng; Zeng, Yixiu; Zhang, Yanding; Xie, Shusen

    2014-09-01

    The gas NO is a ubiquitous intercellular messenger that modulates a wide range of physiological and pathophysiological functions. But few studies were made to study the role of NO in the Ca2+ release in dorsal root ganglion (DRG) neurons by confocal microscopy. Thus the objective of this study was to assess if NO has a role in Ca2+ signaling in DRG neurons using confocal microscopy combined with special fluorescence probe Fluo-3/AM. A 100 μM concentration of the NO donors (Sodium Nitroprusside, Dihydrate, SNP) and NO synthase inhibitor (NG-Monomethyl-L-arginine, Monoacetate salt, L-NMMA) was used in the study. Results showed that the fluorescence intensity increased rapidly after injecting SNP, which indicated that SNP could enhance intracellular Ca2+ release. And the fluorescence intensity shrank gradually with time and kept at a low level for quite a long period after loading with L-NMMA which indicated that L-NMMA could block intracellular Ca2+ release. All these results demonstrated that NO was involved in the regulation of intracellular Ca2+ release in the DRG neurons.

  2. Culture-based Calibration of the Benthic Foraminiferal Mg/Ca Paleothermometer: Initial Results

    Science.gov (United States)

    Lincoln, S. A.; Filipsson, H. L.; Bernhard, J. M.; McCorkle, D. C.; Shimizu, N.; Birdwhistell, S. P.

    2007-12-01

    The magnesium calcium (Mg/Ca) paleothermometer has become a widely used tool for estimating deep water temperatures. To date, calibrations of the proxy have relied on core-top samples; in such studies, water chemistry and biological factors including food supply often co-vary with temperature, making it difficult to isolate the true Mg/Ca / temperature relationship. A multi-temperature culture experiment was conducted at the Woods Hole Oceanographic Institution from December 2006 through May 2007 in order to study the relationship between Mg/Ca and temperature under controlled conditions. Several species of benthic foraminifera were collected from four locations (the Skagerrak and Gullmar Fjord, Sweden; the Bahamas; and the Charleston Bump, United States; 70 to 800 m water depth), and were grown in microcosms under known, constant physical and chemical conditions at 3.5, 7.0, 14.0, and 21 C. Bulimina species ( B. aculeata and B. marginata) were the most successful, reproducing at 7.0 and 14.0 C and adding chambers at all temperatures. These newly added chambers are the focus of our first Mg/Ca analyses. Because cultured benthic foraminifera are typically lightly calcified, sensitive microanalytical techniques with high spatial resolution are required to measure trace element concentrations in single chambers of cultured specimens. We have explored the use of both secondary ion mass spectrometry and laser ablation inductively coupled mass spectrometry for this application, and present preliminary Mg/Ca data from Bulimina species across the experimental temperature range.

  3. Prediction of adsorption of small molecules in porous materials based on ab initio force field method

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Computational prediction of adsorption of small molecules in porous materials has great impact on the basic and applied research in chemical engineering and material sciences. In this work,we report an approach based on grand canonical ensemble Monte Carlo(GCMC) simulations and ab initio force fields. We calculated the adsorption curves of ammonia in ZSM-5 zeolite and hydrogen in MOF-5(a metal-organic-framework material). The predictions agree well with experimental data. Because the predictions are based on the first principle force fields,this approach can be used for the adsorption prediction of new molecules or materials without experimental data as guidance.

  4. High Precision Prediction of Rolling Force Based on Fuzzy and Nerve Method for Cold Tandem Mill

    Institute of Scientific and Technical Information of China (English)

    JIA Chun-yu; SHAN Xiu-ying; NIU Zhao-ping

    2008-01-01

    The rolling force model for cold tandem mill was put forward by using the Elman dynamic recursive network method, based on the actual measured data. Furthermore, a good assumption is put forward, which brings a full universe of discourse self-adjusting factor fuzzy control, closed-loop adjusting, based on error feedback and expertise into a rolling force prediction model, to modify prediction outputs and improve prediction precision and robustness. The simulated results indicate that the method is highly effective and the prediction precision is better than that of the traditional method. Predicted relative error is less than ±4%, so the prediction is high precise for the cold tandem mill.

  5. Environmental Assessment of the Realignment of Units at McChord Air Force Base, Washington

    Science.gov (United States)

    1989-07-01

    McChord AFB (Department of the Air Force 1986). 3.2.4 Water Resources Clovis Creek and Morey Creek are the primary surface water features at McChord AFB...Morey Creek originates at Spanaway Lake east of the base and merges Swith Clovis Creek at n the eastern portion of the base. Clovis Creek has been...estimated at $166.5 million (Department of the Air Force 1988). 3.2.8 Cultura - Resources In the area within and adjacent to McChord AFB, there is evidence

  6. OPTIMAL DESIGN OF A 6-AXIS FORCE TRANSDUCER BASED ON STEWART PLATFORM RELATED TO SENSITIVITY ISOTROPY

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The design method of a 6-axis force robot's transducer based on the Stewart platform is detailed.For this purpose, the sensitivity isotropy evaluation criteria of the transducer are defined, and by the aid of computer, the relationships between the criteria and the parameters of all the transducers based on the Stewart platform are investigated within the geometric model of the solution space, which can provide the theoretical background for the optimal construction design of the 6-axis force transducer related to the sensitivity isotropy.

  7. A radial distribution function-based open boundary force model for multi-centered molecules

    KAUST Repository

    Neumann, Philipp

    2014-06-01

    We derive an expression for radial distribution function (RDF)-based open boundary forcing for molecules with multiple interaction sites. Due to the high-dimensionality of the molecule configuration space and missing rotational invariance, a computationally cheap, 1D approximation of the arising integral expressions as in the single-centered case is not possible anymore. We propose a simple, yet accurate model invoking standard molecule- and site-based RDFs to approximate the respective integral equation. The new open boundary force model is validated for ethane in different scenarios and shows very good agreement with data from periodic simulations. © World Scientific Publishing Company.

  8. Multi-parametric thermal sensing based on NIR emission of Ho(III) doped CaWO4 phosphors

    Science.gov (United States)

    Zhou, Xianju; Wang, Rongxue; Xiang, Guotao; Jiang, Sha; Li, Li; Luo, Xiaobing; Pang, Yu; Tian, Yili

    2017-04-01

    Optical thermometry based on trivalent rare earth doped materials has attracted much attention recently. This article reported the temperature dependent near infrared luminescence of Ho3+ doped in CaWO4 phosphors. A series of CaWO4:Ho3+ powders have been synthesized by high temperature solid state reaction. The XRD patterns showed that the Ho3+ ions have occupied the lattice sites of Ca2+ ions in the phosphors. The thermometry effect was demonstrated by different spectroscopic parameters through the emission intensity of Ho3+: 5I6 → 5I8 transition at ∼1190 nm, the spectral shift of the charge transfer band of W-O and the lifetime of Ho3+: 5F4, 5S2 excited state. These three optical parameters present a simple linear relation with the temperature in the range of 30-300 °C. This allows for accurate thermal sensing based on simultaneous measurement of these parameters. Results show that CaWO4:Ho3+ phosphors might be served as a potential candidate for thermometry.

  9. Accelerated SPECT Monte Carlo Simulation Using Multiple Projection Sampling and Convolution-Based Forced Detection

    Science.gov (United States)

    Liu, Shaoying; King, Michael A.; Brill, Aaron B.; Stabin, Michael G.; Farncombe, Troy H.

    2010-01-01

    Monte Carlo (MC) is a well-utilized tool for simulating photon transport in single photon emission computed tomography (SPECT) due to its ability to accurately model physical processes of photon transport. As a consequence of this accuracy, it suffers from a relatively low detection efficiency and long computation time. One technique used to improve the speed of MC modeling is the effective and well-established variance reduction technique (VRT) known as forced detection (FD). With this method, photons are followed as they traverse the object under study but are then forced to travel in the direction of the detector surface, whereby they are detected at a single detector location. Another method, called convolution-based forced detection (CFD), is based on the fundamental idea of FD with the exception that detected photons are detected at multiple detector locations and determined with a distance-dependent blurring kernel. In order to further increase the speed of MC, a method named multiple projection convolution-based forced detection (MP-CFD) is presented. Rather than forcing photons to hit a single detector, the MP-CFD method follows the photon transport through the object but then, at each scatter site, forces the photon to interact with a number of detectors at a variety of angles surrounding the object. This way, it is possible to simulate all the projection images of a SPECT simulation in parallel, rather than as independent projections. The result of this is vastly improved simulation time as much of the computation load of simulating photon transport through the object is done only once for all projection angles. The results of the proposed MP-CFD method agrees well with the experimental data in measurements of point spread function (PSF), producing a correlation coefficient (r2) of 0.99 compared to experimental data. The speed of MP-CFD is shown to be about 60 times faster than a regular forced detection MC program with similar results. PMID:20811587

  10. Final Programmatic Environmental Assessment for Base-Wide Military Construction Planning at Kirtland Air Force Base, New Mexico

    Science.gov (United States)

    2013-11-01

    whiptail lizard (Aspidoscelis inornata), short- horned lizard (Phrynosoma douglassi), lesser earless lizard (Holbrookia maculata), bull snake (Pituophis...Peterson Field Guide to Western Birds. Houghton Mifflin Pub: Boston. pp. 432. Reid, F.A. 2006. Mammals of North America . Houghton Mifflin...ASSESSMENT FOR BASE-WIDE MILITARY CONSTRUCTION PLANNING AT KIRTLAND AIR FORCE BASE, NEW MEXICO Introduction : In accordance with the National

  11. Ca stabilized zirconia based composites by wet consolidation of zirconia and high alumina cement mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Bruni, Y.L.; Garrido, L.B.; Aglietti, E.F., E-mail: lgarrido@cetmic.unlp.edu.ar [Centro de Tecnologia de Recursos Minerales y Ceramica (CETMIC/CIC-CONICET La Plata), Buenos Aires (Argentina)

    2012-07-01

    Composites of the CaO-Al{sub 2}O{sub 3}-ZrO{sub 2} system are widely used in many industrial applications. In this study, porous Ca stabilized ZrO{sub 2} composites were developed from a starting mixture of m-ZrO{sub 2} and calcium aluminate cement. Ceramics were produced by wet consolidation of aqueous suspensions with and without corn starch as pore former agent and sintering at 1000-1500 °C. The influence of processing parameters on crystalline phases, sintering behavior and textural characteristics was examined. Stabilized c-ZrO{sub 2} formed with the composition of Ca{sub 0.15}Zr{sub 0.85}O{sub 1.85}. The sintering of the mixtures lead to porous composites materials. Textural properties were analyzed considering the initial composition and the present crystalline phases. (author)

  12. Integration of calcium and chemical looping combustion using composite CaO/CuO-based materials.

    Science.gov (United States)

    Manovic, Vasilije; Anthony, Edward J

    2011-12-15

    Calcium looping cycles (CaL) and chemical looping combustion (CLC) are two new, developing technologies for reduction of CO(2) emissions from plants using fossil fuels for energy production, which are being intensively examined. Calcium looping is a two-stage process, which includes oxy-fuel combustion for sorbent regeneration, i.e., generation of a concentrated CO(2) stream. This paper discuss the development of composite materials which can use copper(II)-oxide (CuO) as an oxygen carrier to provide oxygen for the sorbent regeneration stage of calcium looping. In other words, the work presented here involves integration of calcium looping and chemical looping into a new class of postcombustion CO(2) capture processes designated as integrated CaL and CLC (CaL-CLC or Ca-Cu looping cycles) using composite pellets containing lime (CaO) and CuO together with the addition of calcium aluminate cement as a binder. Their activity was tested in a thermogravimetric analyzer (TGA) during calcination/reduction/oxidation/carbonation cycles. The calcination/reduction typically was performed in methane (CH(4)), and the oxidation/carbonation stage was carried out using a gas mixture containing both CO(2) and O(2). It was confirmed that the material synthesized is suitable for the proposed cycles; with the very favorable finding that reduction/oxidation of the oxygen carrier is complete. Various schemes for the Ca-Cu looping process have been explored here that would be compatible with these new composite materials, along with some different possibilities for flow directions among carbonator, calciner, and air reactor.

  13. DNA-based digital tension probes reveal integrin forces during early cell adhesion

    Science.gov (United States)

    Zhang, Yun; Ge, Chenghao; Zhu, Cheng; Salaita, Khalid

    2014-10-01

    Mechanical stimuli profoundly alter cell fate, yet the mechanisms underlying mechanotransduction remain obscure because of a lack of methods for molecular force imaging. Here to address this need, we develop a new class of molecular tension probes that function as a switch to generate a 20- to 30-fold increase in fluorescence upon experiencing a threshold piconewton force. The probes employ immobilized DNA hairpins with tunable force response thresholds, ligands and fluorescence reporters. Quantitative imaging reveals that integrin tension is highly dynamic and increases with an increasing integrin density during adhesion formation. Mixtures of fluorophore-encoded probes show integrin mechanical preference for cyclized RGD over linear RGD peptides. Multiplexed probes with variable guanine-cytosine content within their hairpins reveal integrin preference for the more stable probes at the leading tip of growing adhesions near the cell edge. DNA-based tension probes are among the most sensitive optical force reporters to date, overcoming the force and spatial resolution limitations of traction force microscopy.

  14. Effectiveness of growth regulators, based on the heterylcarbon acid, on forcing of Tulips (Tulips HD

    Directory of Open Access Journals (Sweden)

    Derevianko Natalia

    2016-03-01

    Full Text Available The main factor in growing flowers for forcing is their rate of growth, on account of the fact that in short period of time it is necessary to grow quickly a large number of flowers and to cut them simultaneously. The influence of growth regulators (GR based on heterylcarbon acid on the forcing of tulips in greenhouse conditions (winter period was studied. It was determined that the application of GR1 of the basic within tulip’s forcing period reduces in average to 5 days (from all period of forcing. In case of application GR2 the tulip’s forcing period also reduces to 3 days (from all period of forcing compared with a control group of tulips. The ability of the plant growth regulators under research to accelerate growing properties of flowers is associated with the presence of heterylcarbon acid and potassium ions in their structure of substances. These growth regulators relate to non-toxic compounds and possess antioxidant properties.

  15. AFM-based force spectroscopy measurements of mature amyloid fibrils of the peptide glucagon

    Energy Technology Data Exchange (ETDEWEB)

    Dong Mingdong; Hovgaard, Mads Bruun; Mamdouh, Wael; Xu Sailong; Otzen, Daniel Erik; Besenbacher, Flemming [Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, DK-8000 Aarhus C (Denmark)], E-mail: dao@inano.dk, E-mail: fbe@inano.dk

    2008-09-24

    We report on the mechanical characterization of individual mature amyloid fibrils by atomic force microscopy (AFM) and AFM-based single-molecule force spectroscopy (SMFS). These self-assembling materials, formed from the 29-residue amphiphatic peptide hormone glucagon, were found to display a reversible elastic behaviour. Based on AFM morphology and SMFS studies, we suggest that the observed elasticity is due to a force-induced conformational transition which is reversible due to the {beta}-helical conformation of protofibrils, allowing a high degree of extension. The elastic properties of such mature fibrils contribute to their high stability, suggesting that the internal hydrophobic interactions of amyloid fibrils are likely to be of fundamental importance in the assembly of amyloid fibrils and therefore for the understanding of the progression of their associated pathogenic disorders. In addition, such biological amyloid fibril structures with highly stable mechanical properties can potentially be used to produce nanofibres (nanowires) that may be suitable for nanotechnological applications.

  16. Learning-based force servoing control of a robot with vision in an unknown environment

    Institute of Scientific and Technical Information of China (English)

    肖南峰

    2004-01-01

    A learning-based control approach is presented for force servoing of a robot with vision in an unknown environment. Firstly, mapping relationships between image features of the servoing object and the joint angles of the robot are derived and learned by a neural network. Secondly, a learning controller based on the neural network is designed for the robot to trace the object. Thirdly, a discrete time impedance control law is obtained for the force servoing of the robot,the on-line learning algorithms for three neural networks are developed to adjust the impedance parameters of the robot in the unknown environment. Lastly, wiping experiments are carried out by using a 6 DOF industrial robot with a CCD camera and a force/torque sensor in its end effector, and the experimental results confirm the effectiveness of the approach.

  17. Design of a new torque standard machine based on a torque generation method using electromagnetic force

    Science.gov (United States)

    Nishino, Atsuhiro; Ueda, Kazunaga; Fujii, Kenichi

    2017-02-01

    To allow the application of torque standards in various industries, we have been developing torque standard machines based on a lever deadweight system, i.e. a torque generation method using gravity. However, this method is not suitable for expanding the low end of the torque range, because of the limitations to the sizes of the weights and moment arms. In this study, the working principle of the torque generation method using an electromagnetic force was investigated by referring to watt balance experiments used for the redefinition of the kilogram. Applying this principle to a rotating coordinate system, an electromagnetic force type torque standard machine was designed and prototyped. It was experimentally demonstrated that SI-traceable torque could be generated by converting electrical power to mechanical power. Thus, for the first time, SI-traceable torque was successfully realized using a method other than that based on the force of gravity.

  18. A pairwise residue contact area-based mean force potential for discrimination of native protein structure

    Directory of Open Access Journals (Sweden)

    Pezeshk Hamid

    2010-01-01

    Full Text Available Abstract Background Considering energy function to detect a correct protein fold from incorrect ones is very important for protein structure prediction and protein folding. Knowledge-based mean force potentials are certainly the most popular type of interaction function for protein threading. They are derived from statistical analyses of interacting groups in experimentally determined protein structures. These potentials are developed at the atom or the amino acid level. Based on orientation dependent contact area, a new type of knowledge-based mean force potential has been developed. Results We developed a new approach to calculate a knowledge-based potential of mean-force, using pairwise residue contact area. To test the performance of our approach, we performed it on several decoy sets to measure its ability to discriminate native structure from decoys. This potential has been able to distinguish native structures from the decoys in the most cases. Further, the calculated Z-scores were quite high for all protein datasets. Conclusions This knowledge-based potential of mean force can be used in protein structure prediction, fold recognition, comparative modelling and molecular recognition. The program is available at http://www.bioinf.cs.ipm.ac.ir/softwares/surfield

  19. A Modernized UDM-600 Dynamometer-Based Setup for the Cutting Force Measurement

    Directory of Open Access Journals (Sweden)

    Ya. I. Shuliak

    2016-01-01

    Full Text Available The article considers development of a modernized UDM-600 dynamometer-based setup for measuring the cutting force components. Modernization of existing equipment to improve the method of recording the cutting force components in the automated mode is of relevance. The measuring setup allows recording the cutting force components in turning and milling, as well as the axial force and the torque in the drilling and milling operations.The article presents a block diagram and a schematic diagram of the setup to measure the cutting force components, and describes a basic principle of measuring units within the modernized setup. The developed setup uses a half-bridge strain gauge measuring circuit to record the cutting forces. To enhance the measuring circuit output voltage is used a 16-channel amplifier of LA-UN16 model with a discretely adjustable gain. To record and process electrical signals is used a data acquisition device of NI USB-6009 model, which enables transmitting the received data to a PC via USB-interface. The data acquisition device has a built-in stabilized DC power supply that is used to power the strain gauge bridges. A developed schematic diagram of the measuring setup allows us to realize this measuring device and implement its modernization.Final processing of recorded data is provided through the software developed in visual programming environment LabVIEW 9.0. The program allows us to show the real-time measuring values of the cutting force components graphically and to record the taken data to a text file.The measuring setup modernization enabled increasing measurement accuracy and reducing time for processing and analysis of experimental data obtained when measuring the cutting force components. The MT2 Department of BMSTU uses it in education and research activities and in experimental efforts and laboratory classes.

  20. Creep force modelling for rail traction vehicles based on the Fastsim algorithm

    Science.gov (United States)

    Spiryagin, Maksym; Polach, Oldrich; Cole, Colin

    2013-11-01

    The evaluation of creep forces is a complex task and their calculation is a time-consuming process for multibody simulation (MBS). A methodology of creep forces modelling at large traction creepages has been proposed by Polach [Creep forces in simulations of traction vehicles running on adhesion limit. Wear. 2005;258:992-1000; Influence of locomotive tractive effort on the forces between wheel and rail. Veh Syst Dyn. 2001(Suppl);35:7-22] adapting his previously published algorithm [Polach O. A fast wheel-rail forces calculation computer code. Veh Syst Dyn. 1999(Suppl);33:728-739]. The most common method for creep force modelling used by software packages for MBS of running dynamics is the Fastsim algorithm by Kalker [A fast algorithm for the simplified theory of rolling contact. Veh Syst Dyn. 1982;11:1-13]. However, the Fastsim code has some limitations which do not allow modelling the creep force - creep characteristic in agreement with measurements for locomotives and other high-power traction vehicles, mainly for large traction creep at low-adhesion conditions. This paper describes a newly developed methodology based on a variable contact flexibility increasing with the ratio of the slip area to the area of adhesion. This variable contact flexibility is introduced in a modification of Kalker's code Fastsim by replacing the constant Kalker's reduction factor, widely used in MBS, by a variable reduction factor together with a slip-velocity-dependent friction coefficient decreasing with increasing global creepage. The proposed methodology is presented in this work and compared with measurements for different locomotives. The modification allows use of the well recognised Fastsim code for simulation of creep forces at large creepages in agreement with measurements without modifying the proven modelling methodology at small creepages.

  1. [Force-based local navigation in robot-assisted implantation bed anlage in the lateral skull base. An experimental study].

    Science.gov (United States)

    Plinkert, P K; Federspil, P A; Plinkert, B; Henrich, D

    2002-03-01

    Excellent precision, miss of retiring, reproducibility are main characteristics of robots in the operating theatre. Because of these facts their use for surgery in the lateral scull base is of great interest. In recent experiments we determined process parameters for robot assisted reaming of a cochlea implant bed and for a mastoidectomy. These results suggested that optimizing parameters for thrilling with the robot is needed. Therefore we implemented a suitable reaming curve from the geometrical data of the implant and a force controlled process control for robot assisted reaming at the lateral scull base. Experiments were performed with an industrial robot on animal and human scull base specimen. Because of online force detection and feedback of sensory data the reaming with the robot was controlled. With increasing force values above a defined limit feed rates were automatically regulated. Furthermore we were able to detect contact of the thrill to dura mater by analyzing the force values. With the new computer program the desired implant bed was exactly prepared. Our examinations showed a successful reaming of an implant bed in the lateral scull base with a robot. Because of a force controlled reaming process locale navigation is possible and enables careful thrilling with a robot.

  2. Measure of the magnitude of Young's modulus in whisker-like samples of the Bi-based high-Tc materials Bi sub 2 Sr sub 2 CaCu sub 2 O sub x and Bi sub 2 Sr sub 2 Ca sub 2 Cu sub 3 O sub x

    Energy Technology Data Exchange (ETDEWEB)

    Tritt, T.M.; Ehrlich, A.C.; Gillespie, D.J. (Materials Physics Branch, Naval Research Lab., Washington, DC (USA)); Marone, M.; Chen Xinfen; Skove, M.J.; Tessema, G.X. (Clemson Univ., Dept. of Physics, SC (USA)); Franck, J.P.; Jung, J. (Univ. of Alberta, Dept. of Physics, Edmonton, AB (Canada))

    1991-08-01

    We have measured Young's modulus in ribbon-like whisker samples of the high-Tc materials: Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} and Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x}. This is the first direct measurement of Young's modulus for whiskers of any of the high Tc materials. We used a stress-strain probe that applies an axial force (uniaxial stress) to the whisker-like sample and simultaneously measures the corresponding sample elongation. The slope of the resulting stress-strain curve yields the magnitude of Young's modulus (Y). We found these Bi based high-Tc materials to be soft with Y {approx equal} 20 GPa for Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} and Y {approx equal} 25 GPa for Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x}. (orig.).

  3. Harmonic force microscope: A new tool for biomolecular identification and material characterization based on nanomechanical measurements

    Science.gov (United States)

    Sahin, Ozgur

    At the molecular level, physical and chemical properties of materials are tightly coupled to the mechanical properties. The potential of mechanics for interacting with matter at the nanoscale has been largely unexplored due to lack of instruments capable of performing mechanical measurements at nanometer length scales. This thesis describes nanomechanical sensing techniques and applications based on time-resolved tip-sample force measurements in tapping-mode atomic force microscopy. Tapping mode is the most successful operation mode of atomic force microscopes. Theoretical calculations presented in the first part of this thesis show that time variations of the tip-sample forces in the tapping-mode depend on the physical and chemical properties of the sample and therefore, have the potential to be used for nanomechanical measurements. Unfortunately, the force-sensing probe of the tapping-mode atomic force microscope, the vibrating cantilever, is limited in its response to the variations of forces in time within a period of oscillations. We are describing two types of special micromachined cantilevers that enable measurements of time variations of tip-sample forces: the harmonic cantilever and the coupled torsional cantilever. These special cantilevers allow sensitive mechanical measurements at the nanoscale and single molecular level. The operation of these cantilevers does not require any modifications to the existing atomic force microscopy systems. With the nanomechanical sensing techniques we have developed, we investigated phase transformations of sub-micron domains of composite polymers and observed their glass transitions for the first time. Conventional measurements on bulk properties of these samples do not provide information on the physical changes at the nanoscale. Studies on nucleic acids attached to a surface, a configuration commonly used in DNA microarray technology, showed that the hybridized DNA molecules can be detected at the single molecule

  4. Analyzing excitation forces acting on a plate based on measured acoustic pressure.

    Science.gov (United States)

    Wu, Sean F; Zhou, Pan

    2016-07-01

    This paper presents a theoretical study on "seeing" through an elastic structure to uncover the root cause of sound and vibration by using nearfield acoustical holography (NAH) and normal modes expansion. This approach is of generality because vibro-acoustic responses on the surface of a vibrating structure can always be reconstructed, exactly or approximately. With these vibro-acoustic responses, excitation forces acting on the structure can always be determined, analytically or numerically, given any set of boundary conditions. As an example, the explicit formulations for reconstructing time-harmonic excitation forces, including point, line and surface forces, and their arbitrary combinations acting on a rectangular thin plate in vacuum mounted on an infinite baffle are presented. The reason for choosing this example is that the analytic solutions to vibro-acoustic responses are available, and in-depth analyses of results are possible. Results demonstrate that this approach allows one to identify excitation forces based on measured acoustic pressures and reveal their characteristics such as locations, types and amplitudes, as if one could "see" excitation forces acting behind the plate based on acoustic pressure measured on the opposite side. This approach is extendable to general elastic structures, except that in such circumstance numerical results must be sought.

  5. A Wavelet-Based Method to Predict Muscle Forces From Surface Electromyography Signals in Weightlifting

    Institute of Scientific and Technical Information of China (English)

    Gaofeng Wei; Feng Tian; Gang Tang; Chengtao Wang

    2012-01-01

    The purpose of this study was to develop a wavelet-based method to predict muscle forces from surface electromyography (EMG) signals in vivo.The weightlifting motor task was implemented as the case study.EMG signals of biceps brachii,triceps brachii and deltoid muscles were recorded when the subject carried out a standard weightlifting motor task.The wavelet-based algorithm was used to process raw EMG signals and extract features which could be input to the Hill-type muscle force models to predict muscle forces.At the same time,the musculoskeletal model of subject's weightlifting motor task was built and simulated using the Computed Muscle Control (CMC) method via a motion capture experiment.The results of CMC were compared with the muscle force predictions by the proposed method.The correlation coefficient between two results was 0.99(p<0.01).However,the proposed method was easier and more efficiency than the CMC method.It has potential to be used clinically to predict muscle forces in vivo.

  6. Lift vs. drag based mechanisms for vertical force production in the smallest flying insects.

    Science.gov (United States)

    Jones, S K; Laurenza, R; Hedrick, T L; Griffith, B E; Miller, L A

    2015-11-01

    We used computational fluid dynamics to determine whether lift- or drag-based mechanisms generate the most vertical force in the flight of the smallest insects. These insects fly at Re on the order of 4-60 where viscous effects are significant. Detailed quantitative data on the wing kinematics of the smallest insects is not available, and as a result both drag- and lift-based strategies have been suggested as the mechanisms by which these insects stay aloft. We used the immersed boundary method to solve the fully-coupled fluid-structure interaction problem of a flexible wing immersed in a two-dimensional viscous fluid to compare three idealized hovering kinematics: a drag-based stroke in the vertical plane, a lift-based stroke in the horizontal plane, and a hybrid stroke on a tilted plane. Our results suggest that at higher Re, a lift-based strategy produces more vertical force than a drag-based strategy. At the Re pertinent to small insect hovering, however, there is little difference in performance between the two strategies. A drag-based mechanism of flight could produce more vertical force than a lift-based mechanism for insects at Re<5; however, we are unaware of active fliers at this scale.

  7. Accurate determination of the Ca2+ activity in milk-based systems by Ca-ISE: Effects of ionic composition on the single Ca2+ activitiy coefficient and liquid junction potentials

    NARCIS (Netherlands)

    Gao, R.; Leeuwen, van H.P.; Valenberg, van H.J.F.; Boekel, van M.A.J.S.

    2011-01-01

    Calcium ion selective electrode (Ca-ISE) was found to underestimate the actual Ca2+ ion activity in simulated milk ultrafiltrate (SMUF) and milk. It is shown that the ionic compositional difference between conventional calibration solutions and milk type samples had a significant effect on the singl

  8. Air Force Electronic Systems Center: Reorganization Resulted in Workforce Reassignments at Hanscom Air Force Base, but Other Possible Effects Are Not Yet Known

    Science.gov (United States)

    2013-04-01

    Officer VERA/VSIP Voluntary Early Retirement Authority/Voluntary Separation Incentive Payments This is a work of the U.S. government and is not...force, Hanscom Air Force Base officials used three rounds of the Voluntary Early Retirement Authority/Voluntary Separation Incentive Payments (VERA...by early retirement , voluntary retirement, or resignation. The Homeland Security Act of 2002, Pub. L. No. 107-296, §1313(b), authorized these

  9. Environmental Assessment: 13th Street Bridge Emergency Repair and Retrofit Vandenberg Air Force Base California

    Science.gov (United States)

    2003-06-23

    23-1 Acres on Vandenberg Air Force Base. Robert 0. Gibson, Archaeologist, Paso Robles, California. Submitted toURS Corporation, Santa Barbara...Timbrook (editors). 1977. The Eye (?f the Flute: Chwnash Traditional History and Ritual, as told by Fernando Librado Kitsepmvit to John P. Harrington

  10. Space Shuttle Endeavour flares for landing at Edwards Air Force Base, California to conclude STS-100

    Science.gov (United States)

    2001-01-01

    At the conclusion of Space Shuttle Mission STS-100, Endeavour landed at Edwards Air Force Base, California, May 1, 2001. There the Orbiter would be readied by technicians at NASA's Dryden Flight Research Center for return to Kennedy Space Center, Florida, atop a 747 carrier aircraft.

  11. Landing of STS-59 Shuttle Endeavour at Edwards Air Force Base

    Science.gov (United States)

    1994-01-01

    The main landing gear of the Space Shuttle Endeavour touches down at Edwards Air Force Base to complete the 11 day STS-59/SRL-1 mission. Landing occured at 9:54 a.m., April 20, 1994. Mission duration was 11 days, 5 hours, 49 minutes.

  12. A long telephoto lens captured Space Shuttle Endeavour landing at Edwards Air Force Base, California

    Science.gov (United States)

    2001-01-01

    A long telephoto lens captured Space Shuttle Endeavour landing at Edwards Air Force Base, California, on May 1, 2001. NASA's Dryden Flight Research Center at Edwards would subsequently service the shuttle and mount it on a 747 for the ferry flight to the Kennedy Space Center in Florida.

  13. Modeling the desired direction in a force-based model for pedestrian dynamics

    CERN Document Server

    Chraibi, Mohcine; Schadschneider, Andreas; Seyfried, Armin

    2012-01-01

    We introduce an enhanced model based on the generalized centrifugal force model. Furthermore, the desired direction of pedestrians is investigated. A new approach leaning on the well-known concept of static and dynamic floor-fields in cellular automata is presented. Numerical results of the model are presented and compared with empirical data.

  14. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    This report presents information related to the sampling of ground water at the Wright-Patterson Air Force Base. It is part of an investigation into possible ground water contamination. Information concerns well drilling/construction; x-ray diffraction and sampling; soil boring logs; and chain-of-custody records.

  15. Consequences of Forcing Consumers to Use Technology-Based Self-Service

    NARCIS (Netherlands)

    Reinders, M.J.; Dabholkar, P.A.; Frambach, R.T.

    2008-01-01

    Today, traditional full service is increasingly replaced with technology-based self-service (TBSS), sometimes with no other option for service delivery. This study develops a conceptual model to investigate the impact of forcing consumers to use TBSS. The model is tested using an experimental design

  16. Use of atomic force microscopy to quantify slip irreversibility in a nickel-base superalloy

    Energy Technology Data Exchange (ETDEWEB)

    Risbet, M.; Feaugas, X.; Guillemer-Neel, C.; Clavel, M

    2003-09-15

    Atomic force microscopy was used to study the evolution of surface deformation during cyclic loading in a nickel-base superalloy. Cyclic slip irreversibility has been investigated using quantitative evaluation of extrusion heights and inter-band spacing. This approach is applied to formulate a microscopic crack initiation law, compared to a classical Manson-Coffin relationship.

  17. Atomic Steps with tuning-fork-based noncontact atomic force microscopy

    NARCIS (Netherlands)

    Rensen, W.H.J.; Hulst, van N.F.; Ruiter, A.G.T.; West, P.E.

    1999-01-01

    Tuning forks as tip-sample distance detectors are a promising and versatile alternative to conventional cantilevers with optical beam deflection in noncontact atomic force microscopy (AFM). Both theory and experiments are presented to make a comparison between conventional and tuning-fork-based AFM.

  18. 33 CFR 334.560 - Banana River at Patrick Air Force Base, Fla.; restricted area.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Banana River at Patrick Air Force Base, Fla.; restricted area. 334.560 Section 334.560 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.560...

  19. STEAM ENHANCED REMEDIATION RESEARCH FOR DNAPL IN FRACTURED ROCK, LORING AIR FORCE BASE, LIMESTONE, MAINE

    Science.gov (United States)

    This report details a research project on Steam Enhanced Remediation (SER) for the recovery of volatile organic compounds from fractured limestone that was carried out at the Quarry at the former Loring Air Force Base in Limestone, Maine. This project was carried out by USEPA, Ma...

  20. Environmental Assessment. Increase Fuel Storage Capacity, Dover Air Force Base, Delaware

    Science.gov (United States)

    2012-06-01

    in 1998. Grasshopper Sparrow 2 Observed on Bergold Farm 16 July 2003 and in 1998. Great blue heron 2 Observed many times foraging along both Pipe...ENVIRONMENTAL CONSEQUENCES Increase Fuels Capacity Dover Air Force Base, Delaware 28 calculations were derived from the same EPA software utilized to

  1. Eielson Air Force Base Infrastructure Development in Support of RED FLAG-Alaska Environmental Assessment

    Science.gov (United States)

    2007-08-01

    MAAS Colonel, USAF Vice Commander Date EIELSON AIR FORCE BASE INFRASTRUCTURE DEVELOPMENT IN SUPPORT OF RED FLAG-ALASKA...Name Address1 Address2 Address3 City State Zip Governor of Alaska Palin The Honorable Sarah 240 Main St., Ste. 300 Court Plaza Bldg. Juneau AK 99801

  2. Imaging soft samples in liquid with tuning fork based shear force microscopy

    NARCIS (Netherlands)

    Rensen, W.H.J.; van Hulst, N.F.; Kammer, S.B.

    2000-01-01

    We present a study of the dynamic behavior of tuning forks and the application of tuning fork based shear force microscopy o­n soft samples in liquid. A shift in resonance frequency and a recovery of the tip vibration amplitude have been observed upon immersion into liquid. Conservation of the

  3. Dynamic simulation of land use change in Jihe watershed based on CA-Markov model%基于CA-Markov模型的藉河流域土地利用变化动态模拟

    Institute of Scientific and Technical Information of China (English)

    王友生; 余新晓; 贺康宁; 李庆云; 张由松; 宋思铭

    2011-01-01

    To explore the law of land use change and driving force in Loess hilly-gully area in Jihe watershed, based on the land use data interpretation from remote sensing images in 1995 and 2008, the degree of dynamic change of land use type in Jihe watershed was analyzed by dynamic degree model and spatial analysis model, and distribution of land use spatial patterns in 2022 was forecast by using the CA-Markov model. The results showed that spatial analysis model not only took the conversion process into account but also the spatial expansion process of land use change, so it could more precisely measure the dynamic change rate of land use. The simulation result by the CA-Markov method indicated that, the value of Kappa coefficients of agreement in the whole watershed was 0.9515, and forecasting results were credible. From 2008 to 2022, except for grassland and unused land, trends of land use evolution as well as its rate will keep constant. That is, the area of slope farmland, grassland, water and unused land will continue to reduce in some degree, while terrace, forest land and settlements will present a increasing trend. Because the Loess hilly-gully is a serious soil erosion area, this research is helpful to reinforce the protection of land resource and to enforce the agro-forestry policies of reusing farmland for forestland and grassland, and it is meaningful to serve as a scientific basis for land planning and management.%为了探讨黄土丘陵沟壑区藉河流域的土地利用变化规律及驱动力,基于1995和2008年两期遥感影像解译得到的土地利用数据,通过土地利用动态度模型和空间测算模型对藉河流域土地利用类型的动态变化程度进行分析,并运用CA-Markov模型对2022年土地利用空间格局进行预测.结果表明,空间分析测算模型由于同时考虑了各土地利用类型的空间转移及新增过程,能更为准确地测算出各种土地利用类型的动态变化程度与速率;CA-Markov

  4. Influence of oxygen stoichiometry on Tc and pinning force of Bi sub 2 Sr sub 2 CaCu sub 2 O sub 8+. delta

    Energy Technology Data Exchange (ETDEWEB)

    Vallet-Regi, M. (Dept. de Quimica Inorganica y Bioinorganica, Univ. Complutense, Madrid (Spain) Inst. de Magnetismo Aplicado, Madrid (Spain)); Caneiro, A. (Inst. de Magnetismo Aplicado, Madrid (Spain)); Gonzalez-Calbet, J.M. (Inst. de Magnetismo Aplicado, Madrid (Spain) Dept. de Quimica Inorganica, Univ. Complutense, Madrid (Spain)); Ramirez, J. (Dept. de Quimica Inorganica, Univ. Complutense, Madrid (Spain)); Rillo, C.; Badia, A.; Angurel, L.A.; Lera, F.; Navarro, R. (I.C.M.A., C.S.I.C.-Univ. de Zaragoza (Spain))

    1991-12-01

    The influence of oxygen stoichiometry in Tc and F{sub p} of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} has been investigated by means of X-ray and electron diffraction, a.c. susceptibility and d.c. magnetization. Through proper oxygen control, Tc=94 K and an increase of one order of magnitude in F{sub p} with respect to the started material has been achieved. (orig.).

  5. Involvement of large-conductance Ca2+-activated K+ channels in chloroquine-induced force alterations in pre-contracted airway smooth muscle.

    Directory of Open Access Journals (Sweden)

    Ming-Yu Wei

    Full Text Available The participation of large-conductance Ca2+ activated K+ channels (BKs in chloroquine (chloro-induced relaxation of precontracted airway smooth muscle (ASM is currently undefined. In this study we found that iberiotoxin (IbTx, a selective inhibitor of BKs and chloro both completely blocked spontaneous transient outward currents (STOCs in single mouse tracheal smooth muscle cells, which suggests that chloro might block BKs. We further found that chloro inhibited Ca2+ sparks and caffeine-induced global Ca2+ increases. Moreover, chloro can directly block single BK currents completely from the intracellular side and partially from the extracellular side. All these data indicate that the chloro-induced inhibition of STOCs is due to the blockade of chloro on both BKs and ryanodine receptors (RyRs. We also found that low concentrations of chloro resulted in additional contractions in tracheal rings that were precontracted by acetylcholine (ACH. Increases in chloro concentration reversed the contractile actions to relaxations. In the presence of IbTx or paxilline (pax, BK blockers, chloro-induced contractions were inhibited, although the high concentrations of chloro-induced relaxations were not affected. Taken together, our results indicate that chloro blocks BKs and RyRs, resulting in abolishment of STOCs and occurrence of contraction, the latter will counteract the relaxations induced by high concentrations of chloro.

  6. Data on wells in the Edwards Air Force Base area, California

    Science.gov (United States)

    Dutcher, L.C.; Bader, J.S.; Hiltgen, W.J.

    1962-01-01

    The data presented In this report were collected by the U.S. Geological Survey as a phase of the investigation of ground-water geology and hydrology of the Edwards Air Force Base area. The study was made in cooperation with the Department of the Air Force but also was coincident with the U.S. Geological Survey investigation of water wells and general hydrologic conditions throughout much of the desert region of southern California. The overall study of general hydrologic conditions in the desert is part of a cooperative program with the California Department of Water Resources.

  7. Multi-Axis Force/Torque Sensor Based on Simply-Supported Beam and Optoelectronics

    OpenAIRE

    Noh, Yohan; Bimbo, Joao; Sareh, Sina; Wurdemann, Helge; Fraś, Jan; Chathuranga, Damith Suresh; Liu, Hongbin; Housden, James; Althoefer, Kaspar; Rhode, Kawal

    2016-01-01

    This paper presents a multi-axis force/torque sensor based on simply-supported beam and optoelectronic technology. The sensor’s main advantages are: (1) Low power consumption; (2) low-level noise in comparison with conventional methods of force sensing (e.g., using strain gauges); (3) the ability to be embedded into different mechanical structures; (4) miniaturisation; (5) simple manufacture and customisation to fit a wide-range of robot systems; and (6) low-cost fabrication and assembly of s...

  8. A first-principles based force-field for Li+ and OH- in ethanolic solution.

    Science.gov (United States)

    Milek, Theodor; Meyer, Bernd; Zahn, Dirk

    2013-10-14

    We report on the development of force-field parameters for accurately modeling lithium and hydroxide ions in ethanol in solution. Based on quantum calculations of small molecular clusters mimicking the solvent structure of individual ions as well as the solvated LiOH dimer, significant improvements of off-the-shelf force-fields are obtained. The quality of our model is demonstrated by comparison to ab initio molecular dynamics of the bulk solution and to experimental data available for ethanol/water mixtures.

  9. Mountain Home Air Force Base, Idaho Geothermal Resource Assessment and Future Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Joseph C. Armstrong; Robert P. Breckenridge; Dennis L. Nielson; John W. Shervais; Thomas R. Wood

    2013-03-01

    The U.S. Air Force is facing a number of challenges as it moves into the future, one of the biggest being how to provide safe and secure energy to support base operations. A team of scientists and engineers met at Mountain Home Air Force Base in early 2011 near Boise, Idaho, to discuss the possibility of exploring for geothermal resources under the base. The team identified that there was a reasonable potential for geothermal resources based on data from an existing well. In addition, a regional gravity map helped identify several possible locations for drilling a new well. The team identified several possible sources of funding for this well—the most logical being to use U.S. Department of Energy funds to drill the upper half of the well and U.S. Air Force funds to drill the bottom half of the well. The well was designed as a slimhole well in accordance with State of Idaho Department of Water Resources rules and regulations. Drilling operations commenced at the Mountain Home site in July of 2011 and were completed in January of 2012. Temperatures increased gradually, especially below a depth of 2000 ft. Temperatures increased more rapidly below a depth of 5500 ft. The bottom of the well is at 5976 ft, where a temperature of about 140°C was recorded. The well flowed artesian from a depth below 5600 ft, until it was plugged off with drilling mud. Core samples were collected from the well and are being analyzed to help understand permeability at depth. Additional tests using a televiewer system will be run to evaluate orientation and directions at fractures, especially in the production zone. A final report on the well exploitation will be forthcoming later this year. The Air Force will use it to evaluate the geothermal resource potential for future private development options at Mountain Home Air Force Base. In conclusion, Recommendation for follow-up efforts include the following:

  10. n型CaMnO3基氧化物热电材料研究进展%Progress in n-type CaMnO3-based Oxide Thermoelectric Materials

    Institute of Scientific and Technical Information of China (English)

    张飞鹏; 郭志超; 刘剑; 王新练; 张坤书

    2013-01-01

      n型CaMnO3基氧化物是一种具有优异高温热电性能的n型热电材料体系,从CaMnO3基热电氧化物晶体结构、物性、电子结构、电热传输理论以及Ca位掺杂、Mn位掺杂、Ca和Mn位复合掺杂优化其电热输运性能的角度,综述了 n 型 CaMnO3基热电氧化物的最新研究进展,给出了存在的问题和今后研究的方向。%The n-type CaMnO3 oxide based compound is one of the most promising thermoelectric materials due to its high temperature thermoelectric properties. The paper summarizes the CaMnO3 oxide based thermoelectric materials, mainly in terms of the crystal structure, physical properties, electronic structure, thermoelectric transport theory and Ca site doping, Mn site doping, as well as double doping effects on thermoelectric transport properties. And the research issues and orientations in the near future are pointed out.

  11. Prediction of bubble detachment diameter in flow boiling based on force analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chen Deqi [Key Laboratory of Low-grade Energy Utilization Technologies and Systems (Chongqing University), Ministry of Education, Chongqing 400044 (China); Pan Liangming, E-mail: cneng@cqu.edu.cn [Key Laboratory of Low-grade Energy Utilization Technologies and Systems (Chongqing University), Ministry of Education, Chongqing 400044 (China); Ren Song [Key Laboratory of Low-grade Energy Utilization Technologies and Systems (Chongqing University), Ministry of Education, Chongqing 400044 (China)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer All the forces acting on the growing bubbles are taken into account in the model. Black-Right-Pointing-Pointer The bubble contact diameter has significant effect on bubble detachment. Black-Right-Pointing-Pointer Bubble growth force and surface tension are more significant in narrow channel. Black-Right-Pointing-Pointer A good agreement between the predicted and the measured results is achieved. - Abstract: Bubble detachment diameter is one of the key parameters in the study of bubble dynamics and boiling heat transfer, and it is hard to be measured in a boiling system. In order to predict the bubble detachment diameter, a theoretical model is proposed based on forces analysis in this paper. All the forces acting on a bubble are taken into account to establish a model for different flow boiling configurations, including narrow and conventional channels, upward, downward and horizontal flows. A correlation of bubble contact circle diameter is adopted in this study, and it is found that the bubble contact circle diameter has significant effect on bubble detachment. A new correlation taking the bubble contact circle diameter into account for the evaluation of bubble growth force is proposed in this study, and it is found that the bubble growth force and surface tension force are more significant in narrow channel when comparing with that in conventional channel. A visual experiment was carried out in order to verify present model; and the experimental data from published literature are used also. A good agreement between predicted and measured results is achieved.

  12. Environmental Assessment for the 920th Rescue Wing Beddown Patrick Air Force Base, Florida

    Science.gov (United States)

    2005-10-01

    primarily toward the Banana River. Low-levels of contaminants (e.g., VOC, petroleum hydrocarbons, and heavy metals ) have been detected in surficial...there would be a leveling off as new facilities are constructed that would be devoid of asbestos and heavy metal paint issues and won’t require...Force Base (PAFB) is located on a barrier island on the central east coast of Florida, south of the city of Cocoa Beach (see Figure 1). The main base

  13. Installation Restoration Program Records Search for March Air Force Base, California

    Science.gov (United States)

    1984-04-28

    which is bounded by the Jacinto Fault on the east and the Elsinore Fault on the west. Ground surface elevations within the March AFB bound- Z aries...approx- imately one mile south of the base. Lake Mathews, located approximately 10 miles west of the baze, is the terminal reservoir of this aqueduct...State Project water is brought into the Perris Valley via the California Aqueduct, which runs north and east of March Air Force Base. Lake Perris

  14. Atomic Force Microscopy Based Nanorobotics Modelling, Simulation, Setup Building and Experiments

    CERN Document Server

    Xie, Hui; Régnier, Stéphane; Sitti, Metin

    2012-01-01

    The atomic force microscope (AFM) has been successfully used to perform nanorobotic manipulation operations on nanoscale entities such as particles, nanotubes, nanowires, nanocrystals, and DNA since 1990s. There have been many progress on modeling, imaging, teleoperated or automated control, human-machine interfacing, instrumentation, and applications of AFM based nanorobotic manipulation systems in literature. This book aims to include all of such state-of-the-art progress in an organized, structured, and detailed manner as a reference book and also potentially a textbook in nanorobotics and any other nanoscale dynamics, systems and controls related research and education. Clearly written and well-organized, this text introduces designs and prototypes of the nanorobotic systems in detail with innovative principles of three-dimensional manipulation force microscopy and parallel imaging/manipulation force microscopy.

  15. Impedance-Based Cable Force Monitoring in Tendon-Anchorage Using Portable PZT-Interface Technique

    Directory of Open Access Journals (Sweden)

    Thanh-Canh Huynh

    2014-01-01

    Full Text Available In this paper, a portable PZT interface for tension force monitoring in the cable-anchorage subsystem is developed. Firstly, the theoretical background of the impedance-based method is presented. A few damage evaluation approaches are outlined to quantify the variation of impedance signatures. Secondly, a portable PZT interface is designed to monitor impedance signatures from the cable-anchorage subsystem. One degree-of-freedom analytical model of the PZT interface is established to explain how to represent the loss of cable force from the change in the electromechanical impedance of the PZT interface as well as reducing the sensitive frequency band by implementing the interface device. Finally, the applicability of the proposed PZT-interface technique is experimentally evaluated for cable force-loss monitoring in a lab-scaled test structure.

  16. A Noncontact Force Sensor Based on a Fiber Bragg Grating and Its Application for Corrosion Measurement

    Directory of Open Access Journals (Sweden)

    Antonio C. Bruno

    2013-08-01

    Full Text Available A simple noncontact force sensor based on an optical fiber Bragg grating attached to a small magnet has been proposed and built. The sensor measures the force between the magnet and any ferromagnetic material placed within a few millimeters of the sensor. Maintaining the sensor at a constant standoff distance, material loss due to corrosion increases the distance between the magnet and the corroded surface, which decreases the magnetic force. This will decrease the strain in the optical fiber shifting the reflected Bragg wavelength. The measured shift for the optical fiber used was 1.36 nm per Newton. Models were developed to optimize the magnet geometry for a specific sensor standoff distance and for particular corrosion pit depths. The sensor was able to detect corrosion pits on a fuel storage tank bottom with depths in the sub-millimeter range.

  17. EC-FORC: A New Cyclic Voltammetry Based Method for Examining Phase Transitions and Predicting Equilibrium

    CERN Document Server

    Hamad, Ibrahim Abou; Novotny, Mark A; Rikvold, Per Arne

    2007-01-01

    We propose a new, cyclic-voltammetry based experimental technique that can not only differentiate between discontinuous and continuous phase transitions in an adsorbate layer, but also quite accurately recover equilibrium behavior from dynamic analysis of systems with a continuous phase transition. The Electrochemical first-order reversal curve (EC-FORC) diagram for a discontinuous phase transition (nucleation and growth), such as occurs in underpotential deposition, is characterized by a negative region, while such a region does not exist for a continuous phase transition, such as occurs in the electrosorption of Br on Ag(100). Moreover, for systems with a continuous phase transition, the minima of the individual EC-FORCs trace the equilibrium curve, even at very high scan rates. Since obtaining experimental data for the EC-FORC method would require only a simple reprogramming of the potentiostat used in conventional cyclic-voltammetry experiments, we believe that this method has significant potential for ea...

  18. Determination of Quantum Chemistry Based Force Fields for Molecular Dynamics Simulations of Aromatic Polymers

    Science.gov (United States)

    Jaffe, Richard; Langhoff, Stephen R. (Technical Monitor)

    1995-01-01

    Ab initio quantum chemistry calculations for model molecules can be used to parameterize force fields for molecular dynamics simulations of polymers. Emphasis in our research group is on using quantum chemistry-based force fields for molecular dynamics simulations of organic polymers in the melt and glassy states, but the methodology is applicable to simulations of small molecules, multicomponent systems and solutions. Special attention is paid to deriving reliable descriptions of the non-bonded and electrostatic interactions. Several procedures have been developed for deriving and calibrating these parameters. Our force fields for aromatic polyimide simulations will be described. In this application, the intermolecular interactions are the critical factor in determining many properties of the polymer (including its color).

  19. Cutting performance orthogonal test of single plane puncture biopsy needle based on puncture force

    Science.gov (United States)

    Xu, Yingqiang; Zhang, Qinhe; Liu, Guowei

    2017-04-01

    Needle biopsy is a method to extract the cells from the patient's body with a needle for tissue pathological examination. Many factors affect the cutting process of soft tissue, including the geometry of the biopsy needle, the mechanical properties of the soft tissue, the parameters of the puncture process and the interaction between them. This paper conducted orthogonal experiment of main cutting parameters based on single plane puncture biopsy needle, and obtained the cutting force curve of single plane puncture biopsy needle by studying the influence of the inclination angle, diameter and velocity of the single plane puncture biopsy needle on the puncture force of the biopsy needle. Stage analysis of the cutting process of biopsy needle puncture was made to determine the main influencing factors of puncture force during the cutting process, which provides a certain theoretical support for the design of new type of puncture biopsy needle and the operation of puncture biopsy.

  20. Cogging force rejection method of linear motor based on internal model principle

    Science.gov (United States)

    Liu, Yang; Chen, Zhenyu; Yang, Tianbo

    2015-02-01

    The cogging force disturbance of linear motor is one of the main factors affecting the positioning accuracy of ultraprecision moving platform. And this drawback could not be completely overcome by improving the design of motor body, such as location modification of permanent magnet array, or optimization design of the shape of teeth-slot. So the active compensation algorithms become prevalent in cogging force rejection area. This paper proposed a control structure based on internal mode principle to attenuate the cogging force of linear motor which deteriorated the accuracy of position, and this structure could make tracking and anti-disturbing performance of close-loop designed respectively. In the first place, the cogging force was seen as the intrinsic property of linear motor and its model constituting controlled object with motor ontology model was obtained by data driven recursive identification method. Then, a control structure was designed to accommodate tracking and anti-interference ability separately by using internal model principle. Finally, the proposed method was verified in a long stroke moving platform driven by linear motor. The experiment results show that, by employing this control strategy, the positioning error caused by cogging force was decreased by 70%.

  1. Research of three-dimensional force sensor based on multiplexed fiber Bragg grating strain sensors

    Science.gov (United States)

    Xu, Hui-Chao; Wang, Su; Miao, Xin-Gang

    2017-04-01

    Most safety problems of architectural structures are caused by structural deformation, and the structures usually deform in more than one direction. So it is important and necessary to collect the safety monitoring data from all directions. Conventional fiber Bragg grating (FBG) sensors cannot fully meet the requirements of a modern safety monitoring system in practical application. Therefore, the research of a three-dimensional (3-D) force sensor that can expand the application range of fiber optic sensing technology is necessary and significant. A 3-D force sensor based on multiplexed FBG strain sensors is proposed, which can be used to measure 3-D force on a structure under test, force distribution, and the trend of relative microdeformation. The sensor that has an integral structure with a design has been described in detail, and its sensing principle has been investigated. The results of calibration experiments show that it can accurately and effectively realize the 3-D force measurement with good linearity, repeatability, and consistency. Experimental and analytical results both demonstrate its feasibility. It can work in harsh environments due to its good stability and anti-interference ability. The sensor proposed in this paper has great engineering application value and application prospects in the field of structure health monitoring.

  2. Force analysis of pile foundation in rock slope based on upper-bound theorem of limit

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ming-hua; LIU Jian-hua; LIU Dai-quan; WANG You

    2008-01-01

    Based on the characteristic that the potential sliding surfaces of rock slope are commonly in the shape of either line or fold line, analysis thought of conventional pile foundation in the flat ground under complex load condition was applied and the upper-bound theorem of limit analysis was used to compute thrust of rock layers with all possible distribution shapes. The interaction of slope and pile was considered design load in terms of slope thrust, and the finite difference method was derived to calculate inner-force and displacement of bridge pile foundation in rock slope under complex load condition. The result of example shows that the distribution model of slope thrust has certain impact on displacement and inner-force of bridge pile foundation. The maximum displacement growth rate reaches 54% and the maximum moment and shear growth rates reach only 15% and 20%, respectively, but the trends of inner-force and displacement of bridge pile foundation are basically the same as those of the conventional pile foundation in the flat ground. When the piles bear the same level lateral thrust, the distribution shapes of slope thrust have different influence on inner-force of pile foundation, especially the rectangle distribution, and the triangle thrust has the smallest displacement and inner-force of pile foundation.

  3. Ionic force field optimization based on single-ion and ion-pair solvation properties

    CERN Document Server

    Fyta, Maria; Dzubiella, Joachim; Vrbka, Lubos; Netz, Roland R

    2009-01-01

    Molecular dynamics simulations of ionic solutions depend sensitively on the force fields employed for the ions. To resolve the fine differences between ions of the same valence and roughly similar size and in particular to correctly describe ion-specific effects, it is clear that accurate force fields are necessary. In the past, optimization strategies for ionic force fields either considered single-ion properties (such as the solvation free energy at infinite dilution or the ion-water structure) or ion-pair properties (in the form of ion-ion distribution functions). In this paper we investigate strategies to optimize ionic force fields based on single-ion and ion-pair properties simultaneously. To that end, we simulate five different salt solutions, namely CsCl, KCl, NaI, KF, and CsI, at finite ion concentration. The force fields of these ions are systematically varied under the constraint that the single-ion solvation free energy matches the experimental value, which reduces the two-dimensional $\\{\\sigma,\\e...

  4. An Updated Analytical Structural Pounding Force Model Based on Viscoelasticity of Materials

    Directory of Open Access Journals (Sweden)

    Qichao Xue

    2016-01-01

    Full Text Available Based on the summary of existing pounding force analytical models, an updated pounding force analysis method is proposed by introducing viscoelastic constitutive model and contact mechanics method. Traditional Kelvin viscoelastic pounding force model can be expanded to 3-parameter linear viscoelastic model by separating classic pounding model parameters into geometry parameters and viscoelastic material parameters. Two existing pounding examples, the poundings of steel-to-steel and concrete-to-concrete, are recalculated by utilizing the proposed method. Afterwards, the calculation results are compared with other pounding force models. The results show certain accuracy in proposed model. The relative normalized errors of steel-to-steel and concrete-to-concrete experiments are 19.8% and 12.5%, respectively. Furthermore, a steel-to-polymer pounding example is calculated, and the application of the proposed method in vibration control analysis for pounding tuned mass damper (TMD is simulated consequently. However, due to insufficient experiment details, the proposed model can only give a rough trend for both single pounding process and vibration control process. Regardless of the cheerful prospect, the study in this paper is only the first step of pounding force calculation. It still needs a more careful assessment of the model performance, especially in the presence of inelastic response.

  5. Effect of ca2+ to salicylic acid release in pectin based controlled drug delivery system

    Science.gov (United States)

    Kistriyani, L.; Wirawan, S. K.; Sediawan, W. B.

    2016-01-01

    Wastes from orange peel are potentially be utilized to produce pectin, which are currently an import commodity. Pectin can be used in making edible film. Edible films are potentially used as a drug delivery system membrane after a tooth extraction. Drug which is used in the drug delivery system is salicylic acid. It is an antiseptic. In order to control the drug release rate, crosslinking process is added in the manufacturing of membrane with CaCl2.2H2O as crosslinker. Pectin was diluted in water and mixed with a plasticizer and CaCl2.2H2O solution at 66°C to make edible film. Then the mixture was dried in an oven at 50 °C. After edible film was formed, it was coated using plasticizer and CaCl2.2H2O solution with various concentration 0, 0.015, 0.03 and 0.05g/mL. This study showed that the more concentration of crosslinker added, the slower release of salicylic acid would be. This was indicated by the value of diffusivites were getting smaller respectively. The addition of crosslinker also caused smaller gels swelling value,which made the membrane is mechanically stronger

  6. Critical Assessment of P2O5 Activity Coefficients in CaO-based Slags during Dephosphorization Process of Iron-based Melts

    Science.gov (United States)

    Yang, Xue-min; Li, Jin-yan; Chai, Guo-Ming; Duan, Dong-ping; Zhang, Jian

    2016-08-01

    According to the experimental results of hot metal dephosphorization by CaO-based slags at a commercial-scale hot metal pretreatment station, activity a_{{{{P}}_{ 2} {{O}}_{ 5} }} of P2O5 in the CaO-based slags has been determined using the calculated comprehensive mass action concentration N_{{{{Fe}}t {{O}}}}{} of iron oxides by the ion and molecule coexistence theory (IMCT) for representing the reaction ability of Fe t O, i.e., activity of a_{{{{Fe}}t {{O}}}}{} . The collected ten models from the literature for predicting activity coefficient γ_{{{{P}}_{ 2} {{O}}_{ 5} }} of P2O5 in CaO-based slags have been evaluated based on the determined activity a_{{{{P}}_{ 2} {{O}}_{ 5} }} of P2O5 by the IMCT as the criterion. The collected ten models of activity coefficient γ_{{{{P}}_{ 2} {{O}}_{ 5} }} of P2O5 in CaO-based slags can be described in the form of a linear function as log γ_{{{{P}}_{ 2} {{O}}_{ 5} }} ≡ y = c0 + c1 x , in which independent variable x represents the chemical composition of slags, intercept c0 including the constant term depicts temperature effect and other unmentioned or acquiescent thermodynamic factors, and slope c1 is regressed by the experimental results. Thus, a general approach for obtaining good prediction results of activity a_{{{{P}}_{ 2} {{O}}_{ 5} }} of P2O5 in CaO-based slags is proposed by revising the constant term in intercept c0 for the collected ten models. The better models with an ideal revising possibility or flexibility in the collected ten models have been selected and recommended.

  7. A force-based model to reproduce stop-and-go waves in pedestrian dynamics

    CERN Document Server

    Chraibi, Mohcine; Schadschneider, Andreas

    2015-01-01

    Stop-and-go waves in single-file movement are a phenomenon that is ob- served empirically in pedestrian dynamics. It manifests itself by the co-existence of two phases: moving and stopping pedestrians. We show analytically based on a simplified one-dimensional scenario that under some conditions the system can have instable homogeneous solutions. Hence, oscillations in the trajectories and in- stabilities emerge during simulations. To our knowledge there exists no force-based model which is collision- and oscillation-free and meanwhile can reproduce phase separation. We develop a new force-based model for pedestrian dynamics able to reproduce qualitatively the phenomenon of phase separation. We investigate analytically the stability condition of the model and define regimes of parameter values where phase separation can be observed. We show by means of simulations that the predefined conditions lead in fact to the expected behavior and validate our model with respect to empirical findings.

  8. Robust Operation of Tendon-Driven Robot Fingers Using Force and Position-Based Control Laws

    Science.gov (United States)

    Abdallah, Muhammad E (Inventor); Platt, Jr., Robert J. (Inventor); Reiland, Matthew J (Inventor); Hargrave, Brian (Inventor); Diftler, Myron A (Inventor); Strawser, Philip A (Inventor); Ihrke, Chris A. (Inventor)

    2013-01-01

    A robotic system includes a tendon-driven finger and a control system. The system controls the finger via a force-based control law when a tension sensor is available, and via a position-based control law when a sensor is not available. Multiple tendons may each have a corresponding sensor. The system selectively injects a compliance value into the position-based control law when only some sensors are available. A control system includes a host machine and a non-transitory computer-readable medium having a control process, which is executed by the host machine to control the finger via the force- or position-based control law. A method for controlling the finger includes determining the availability of a tension sensor(s), and selectively controlling the finger, using the control system, via the force or position-based control law. The position control law allows the control system to resist disturbances while nominally maintaining the initial state of internal tendon tensions.

  9. Rehabilitation of the Rocket Vehicle Integration Test Stand at Edwards Air Force Base

    Science.gov (United States)

    Jones, Daniel S.; Ray, Ronald J.; Phillips, Paul

    2005-01-01

    Since initial use in 1958 for the X-15 rocket-powered research airplane, the Rocket Engine Test Facility has proven essential for testing and servicing rocket-powered vehicles at Edwards Air Force Base. For almost two decades, several successful flight-test programs utilized the capability of this facility. The Department of Defense has recently demonstrated a renewed interest in propulsion technology development with the establishment of the National Aerospace Initiative. More recently, the National Aeronautics and Space Administration is undergoing a transformation to realign the organization, focusing on the Vision for Space Exploration. These initiatives provide a clear indication that a very capable ground-test stand at Edwards Air Force Base will be beneficial to support the testing of future access-to-space vehicles. To meet the demand of full integration testing of rocket-powered vehicles, the NASA Dryden Flight Research Center, the Air Force Flight Test Center, and the Air Force Research Laboratory have combined their resources in an effort to restore and upgrade the original X-15 Rocket Engine Test Facility to become the new Rocket Vehicle Integration Test Stand. This report describes the history of the X-15 Rocket Engine Test Facility, discusses the current status of the facility, and summarizes recent efforts to rehabilitate the facility to support potential access-to-space flight-test programs. A summary of the capabilities of the facility is presented and other important issues are discussed.

  10. Force transmissibility and vibration power flow behaviour of inerter-based vibration isolators

    Science.gov (United States)

    Yang, Jian

    2016-09-01

    This paper investigates the dynamics and performance of inerter-based vibration isolators. Force / displacement transmissibility and vibration power flow are obtained to evaluate the isolation performance. Both force and motion excitations are considered. It is demonstrated that the use of inerters can enhance vibration isolation performance by enlarging the frequency band of effective vibration isolation. It is found that adding inerters can introduce anti-resonances in the frequency-response curves and in the curves of the force and displacement transmissibility such that vibration transmission can be suppressed at interested excitation frequencies. It is found that the introduction of inerters enhances inertial coupling and thus have a large influence on the dynamic behaviour at high frequencies. It is shown that force and displacement transmissibility increases with the excitation frequency and tends to an asymptotic value as the excitation frequency increases. In the high-frequency range, it was shown that adding inerters can result in a lower level of input power. These findings provide a better understanding of the effects of introducing inerters to vibration isolation and demonstrate the performance benefits of inerter-based vibration isolators.

  11. Highly sensitive force sensor based on optical microfiber asymmetrical Fabry-Perot interferometer.

    Science.gov (United States)

    Gong, Yuan; Yu, Cai-Bin; Wang, Ting-Ting; Liu, Xiu-Ping; Wu, Yu; Rao, Yun-Jiang; Zhang, Ming-Lei; Wu, Hui-Juan; Chen, Xiao-Xiao; Peng, Gang-Ding

    2014-02-10

    An asymmetrical Fabry-Perot interferometric (AFPI) force sensor is fabricated based on a narrowband reflection of low-reflectivity fiber Bragg grating (LR-FBG) and a broadband Fresnel reflection of the cleaved fiber end. The AFPI sensor includes a section of microfiber made by tapering and it achieves a force sensitivity of 0.221 pm/μN with a tapered microfiber of 40 mm length and 6.1 μm waist diameter. Compared with similar AFPI structure in 125 μm-diameter single mode fiber, the force sensitivity of the microfiber AFPI structure is greatly enhanced due to its smaller diameter and can be optimized for different force scales by controlling the diameter. The fabrication process of the AFPI sensor is simple and cost-effective. The AFPI sensor has better multiplexing capacity than conventional extrinsic fiber-optic Fabry-Perot sensors, while it also release the requirement on the wavelength matching of the FBG-pair-based FPI.

  12. Polymer-based flexible capacitive sensor for three-axial force measurements

    Science.gov (United States)

    Dobrzynska, J. A.; Gijs, M. A. M.

    2013-01-01

    We have developed a flexible-substrate-based three-axial force sensor, composed of finger-shaped electrode capacitors, whose operation is based on the measurement of a capacitance change induced upon applying a three-axial load. The electrode design supports high sensitivity to shear forces. An overall flexibility of the sensor and elasticity of the capacitor's dielectric is obtained by integrating three polymers in the sensor's technology process, namely polyimide, parylene-C, and polydimethylsiloxane, combined with standard metallization processes. We have theoretically modeled the sensor's capacitance and its three-axial force sensitivity. The unit capacitors have static capacitances in the range of 20 pF. The electro-mechanical characterization of the capacitors reveals in the normal direction a sensitivity Sz = 0.024 kPa-1 for pressures <10 kPa, whereas for higher pressures the measured sensitivity Sz = 6.6 × 10-4 kPa-1. Typical measured shear force sensitivity Sx = 2.8 × 10-4 kPa-1. These values give our transducer high potential for use in skin-like sensing applications.

  13. 一种基于VDFLL和CaKFPLL的INS/GNSS超紧耦合方法%INS/GNSS ultra-tight coupling based on VDFLL and CaKFPLL

    Institute of Scientific and Technical Information of China (English)

    李传军; 李兴城

    2013-01-01

    为了提高复杂电磁环境下的GNSS抗干扰能力,针对低成本制导武器的导航需求特点,提出了一种基于矢量延迟锁定环和锁频环并级联卡尔曼滤波锁相环的INS/GNSS超紧耦合的改进算法。分析了 INS 辅助矢量跟踪结构,给出了基于鉴别器的低复杂度基带预处理滤波器和基于 EKF 锁相环滤波器的详细设计方法。此外,设计了干扰环境下的高动态飞行轨迹,用于验证INS/GNSS超紧耦合算法,动态仿真试验结果表明,在干扰环境下INS/GNSS超紧耦合系统的导航能力相对于独立式高动态跟踪技术的接收机有明显优势,跟踪GPS L1 C/A情况下,可容忍干信比为48.6 dB,比独立式接收机的干扰抑制能力提高了约12 dB。%In order to improve GNSS’s anti-jamming ability under complex electromagnetic environment, an improved algorithm of INS/GNSS ultra-tight coupling(UTC) based on vector DLL(delay locked loop) and FLL(frequency locked loop) as well as cascade loop filter of phase-locked loop is proposed for low cost guided weapon navigation. The architecture of INS-aided GNSS vector tracking is analyzed, a discriminator-based pre-processing filter for vector tracking is devised to reduce the computational complexity, and an extended Kalman filter for PLL is given. A ballistic trajectory under jamming condition is also designed to test the UTC algorithm. Dynamic simulation test shows that the performance of UTC is better than that of stand-alone high dynamic tracking under interference environment. The UTC can lock GPS L1 C/A signal at J/S level of 48.6 dB which is about 12 dB bigger than stand-alone receiver.

  14. Alternative splicing, muscle contraction and intraspecific variation: associations between troponin T transcripts, Ca(2+) sensitivity and the force and power output of dragonfly flight muscles during oscillatory contraction.

    Science.gov (United States)

    Marden, J H; Fitzhugh, G H; Girgenrath, M; Wolf, M R; Girgenrath, S

    2001-10-01

    The flight muscles of Libellula pulchella dragonflies contain a mixture of six alternatively spliced transcripts of a single troponin T (TnT) gene. Here, we examine how intraspecific variation in the relative abundance of different TnT transcripts affects the Ca(2+) sensitivity of skinned muscle fibers and the performance of intact muscles during work-loop contraction regimes that approximate in vivo conditions during flight. The relative abundance of one TnT transcript, or the pooled relative abundance of two TnT transcripts, showed a positive correlation with a 10-fold range of variation in Ca(2+) sensitivity of skinned fibers (r(2)=0.77, Pmuscle. Using these results to reanalyze previously published data for wing kinematics during free flight, we show that the relative abundances of these particular transcripts are also positively correlated with wingbeat frequency and amplitude. TnT variation alone may be responsible for these effects, or TnT variation may be a marker for changes in a suite of co-regulated molecules. Dragonflies from two ponds separated by 16 km differed significantly in both TnT transcript composition and muscle contractile performance, and within each population there are two distinct morphs that showed different maturational trajectories of TnT transcript composition and muscle contractility. Thus, there is broad intraspecific variability and a high degree of population structure for contractile performance phenotypes, TnT ribotypes and ontogenetic patterns involving these traits that affect locomotor performance.

  15. Programmatic Environmental Assessment for Base General Plan Development, Schriever Air Force Base, Colorado

    Science.gov (United States)

    2012-06-01

    dividers in the parking lots. The tree composition is approximately 45 percent coniferous trees and 55 percent deciduous trees (USAF 2008). An Urban...roadway capacities would be significant if roads with no history of exceeding their designed capacity were forced to operate at or above those capacities

  16. Knowledge-Based Trajectory Error Pattern Method Applied to an Active Force Control Scheme

    Directory of Open Access Journals (Sweden)

    Endra Pitowarno, Musa Mailah, Hishamuddin Jamaluddin

    2012-08-01

    Full Text Available The active force control (AFC method is known as a robust control scheme that dramatically enhances the performance of a robot arm particularly in compensating the disturbance effects. The main task of the AFC method is to estimate the inertia matrix in the feedback loop to provide the correct (motor torque required to cancel out these disturbances. Several intelligent control schemes have already been introduced to enhance the estimation methods of acquiring the inertia matrix such as those using neural network, iterative learning and fuzzy logic. In this paper, we propose an alternative scheme called Knowledge-Based Trajectory Error Pattern Method (KBTEPM to suppress the trajectory track error of the AFC scheme. The knowledge is developed from the trajectory track error characteristic based on the previous experimental results of the crude approximation method. It produces a unique, new and desirable error pattern when a trajectory command is forced. An experimental study was performed using simulation work on the AFC scheme with KBTEPM applied to a two-planar manipulator in which a set of rule-based algorithm is derived. A number of previous AFC schemes are also reviewed as benchmark. The simulation results show that the AFC-KBTEPM scheme successfully reduces the trajectory track error significantly even in the presence of the introduced disturbances.Key Words:  Active force control, estimated inertia matrix, robot arm, trajectory error pattern, knowledge-based.

  17. Rocket propulsion experimental facilities at the Phillips Laboratory, Edwards Air Force Base, California

    Science.gov (United States)

    Beckmann, Joel W.; Kalliomaa, Wayne M.

    The Phillips Laboratory has extensive rocket propulsion faciliteis at Edwards Air Force Base, California. These facilities range form small scale cells capable of firing liquid rocket engines as small as 0.01 lbf (0.04 Newtons (N)) thrust up to very large liquid/solid test stands designed for firings up to 10 million lbf (44.5 million N) thrust. This paper gives a review of the variety and capabilities of the numerous facilities at Edwards Air Force Base, as well as an overview of current projects. Emphasis is placed on the general capabilities of these facilities; specifics are available upon request to the author. Trends in the evolution of rocket test facilities are discussed.

  18. Parallel Processing Based on Ship Maneuvering in Identification of Interaction Force Coefficients

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-jian; HUANG Guo-liang; DENG De-heng

    2008-01-01

    The parallel processing based on the free running model test was adopted to predict the interac-tion force coefficients (flow straightening coefficient and wake fraction) of ship maneuvering. And the multi-population genetic algorithm (MPGA) based on real coding that can contemporarily process the data of freerunning model and simulation of ship maneuvering was applied to solve the problem. Accordingly the optimalindividual was obtained using the method of genetic algorithm. The parallel processing of multi-populationsolved the prematurity in the identification for single population, meanwhile, the parallel processing of the dataof ship maneuvering (turning motion and zigzag motion) is an attempt to solve the coefficient drift problem.In order to validate the method, the interaction force coefficients were verified by the procedure and thesecoefficients measured were compared with those ones identified. The maximum error is less than 5%, and theidentification is an effective method.

  19. A large-stroke compliant joint–based force/displacement integrated sensor

    Directory of Open Access Journals (Sweden)

    Xuechao Duan

    2015-12-01

    Full Text Available The design methodology and validation of a compliant translational joint–based force/displacement integrated sensor is presented in this article. The stiffness analysis of the large displacement high precision compliant translational joint is developed, in which the screw theory–based symbolic formulation method for structures is employed. By combining the stiffness matrix of the single compliant beams and components in this joint, the entire stiffness matrix is derived. The stiffness matrix is validated by finite element analysis (FEA method. Finally, the compliant translational joint was fabricated with a three-dimensional printer and equipped with a linear position sensor and microcontroller. The displacement of the translational joint is measured and then the force is calculated using the stiffness matrix. A calibration is conducted so that the sub-Newton precision of the sensor is achieved.

  20. New enhancements and validation of force based posture and discomfort predictions.

    Science.gov (United States)

    Wirsching, Hans-Joachim; Engstler, Florian

    2012-01-01

    Many digital human models provide the crucial method to calculate postures in virtual environments. Traditionally these methods refer to experiments and make use of statistical modeling. They provide sufficient results in their specialized domain, but cannot be used in general applications. In addition they do not consider important design aspects as forces and discomfort. Hence a new force based approach has been introduced in order to overcome these shortcomings. Based on biomechanical models of active maximal and passive receding joint torques, a mechanical optimization generates static stable postures and related discomfort ratings. The results were promising, but showed some model deficiencies and were not validated in detail. The present paper continues this work and provides necessary model enhancements. Finally the new prediction models are validated on real experiments. The validation results are presented and discussed regarding to usability aspects and future development work.

  1. Analysis of Melting for Alkali Earth and Alkali Oxides Based on the Diffusional Force Theory

    Science.gov (United States)

    Liu, Quan; Chen, Li-Rong

    An analysis of the melting alkali earth and alkali oxides is presented using the concept of diffusional force. The calculations are performed by developing an ionic model based on Harrison's quantum mechanical treatment of overlap repulsive potential which takes into account the interactions up to second neighbors. Van der Waals dipole-dipole and dipole-quadrupole interactions calculated by more accurate methods are also included in the model. Using the formula by Fang, derived on the basis of thermodynamic analysis, the values of interionic distances for 8 alkali earth and alkali oxides at melting have been obtained. A simple model for melting is developed based on the diffusional force models. The values of Tm thus obtained are found to show fairly good agreement with experimental values of melting temperatures.

  2. Selective and visual Ca(2+) ion recognition in solution and in a self-assembly organogel of the terpyridine-based derivative triggered by ultrasound.

    Science.gov (United States)

    Geng, Lijun; Li, Yajuan; Wang, Zengyao; Wang, Yanqiu; Feng, Guoliang; Pang, Xuelei; Yu, Xudong

    2015-11-07

    A new kind of terpyridine-based Ca(2+) sensor TS was designed and studied based on the internal charge transfer (ICT). In the diluted solution state, TS sensed Ca(2+) and Mg(2+) ions among test ions via an "off-on" approach as seen from fluorescence spectra of test ions. Moreover, TS was able to form stable fluorescent gels in organic solvents accelerated by ultrasound, indicating the ultrasound responsive properties of TS molecules. The S-gel of TS could be successfully used to selectively recognize Ca(2+) through fluorescent emission color and morphological changes, which was different from that of the solution state. It was predicated that the competition between the self-assembly of TS molecules and the host–guest interaction of TS with Ca(2+) or Mg(2+) was responsible for the sensing properties. To the best of our knowledge, this is the first example that organogels could selectively sense Ca2+ ions.

  3. Novel knowledge-based mean force potential at the profile level

    Directory of Open Access Journals (Sweden)

    Wang Xiaolong

    2006-06-01

    Full Text Available Abstract Background The development and testing of functions for the modeling of protein energetics is an important part of current research aimed at understanding protein structure and function. Knowledge-based mean force potentials are derived from statistical analyses of interacting groups in experimentally determined protein structures. Current knowledge-based mean force potentials are developed at the atom or amino acid level. The evolutionary information contained in the profiles is not investigated. Based on these observations, a class of novel knowledge-based mean force potentials at the profile level has been presented, which uses the evolutionary information of profiles for developing more powerful statistical potentials. Results The frequency profiles are directly calculated from the multiple sequence alignments outputted by PSI-BLAST and converted into binary profiles with a probability threshold. As a result, the protein sequences are represented as sequences of binary profiles rather than sequences of amino acids. Similar to the knowledge-based potentials at the residue level, a class of novel potentials at the profile level is introduced. We develop four types of profile-level statistical potentials including distance-dependent, contact, Φ/Ψ dihedral angle and accessible surface statistical potentials. These potentials are first evaluated by the fold assessment between the correct and incorrect models generated by comparative modeling from our own and other groups. They are then used to recognize the native structures from well-constructed decoy sets. Experimental results show that all the knowledge-base mean force potentials at the profile level outperform those at the residue level. Significant improvements are obtained for the distance-dependent and accessible surface potentials (5–6%. The contact and Φ/Ψ dihedral angle potential only get a slight improvement (1–2%. Decoy set evaluation results show that the distance

  4. Microscopic driving force in electronic smectic-nematic transition in La1/3Ca2/3MnO3

    Science.gov (United States)

    Tao, Jing; Sun, K.; Yin, W. G.; Pennycook, S. J.; Tranquada, J. M.; Zhu, Y.

    2015-03-01

    Electronic liquid crystal (ELC) phases provide unique descriptions to characterize the electronic structures and elucidate the underlying physics in correlated materials from symmetry perspective. Although ELC phases have been proposed to play a key role in interpreting the structure-property relationship in a wide range of correlated materials, the experimental manifestations of the nature of the transition between such phases have been waiting to be explored. Using transmission electron microscopic tools with recently developed techniques, we studied the electronic smectic-nematic phase transition in La1/3Ca2/3MnO3 by monitoring the evolution of charge ordering and orbital ordering superstructures as a function of temperature. We observed that the transition is driven by the formation of defects and electronic phase separation. In addition, we found that charge inhomogeneity is responsible for the electronic smectic-nematic phase transition in this material.

  5. Landing of STS-58 Orbiter Columbia at Edwards Air Force Base

    Science.gov (United States)

    1993-01-01

    The Space Shuttle Columbia is about to touch down on the runway at Edwards Air Force Base in California. The landing occurred at 7:06 a.m., November 1, 1993 (126); The main landing gear of the Space Shuttle Columbia stirs up dust on the runway at Edwards AFB as it begins to touchdown (127); The nose gear of the Space Shuttle Columbia is about to touch down on the runway at Edwards AFB as Columbia completes its landing procedures (128).

  6. Quantitative Verification of a Force-based Model for Pedestrian Dynamics

    CERN Document Server

    Chraibi, Mohcine; Schadschneider, Andreas; Mackens, Wolfgang

    2009-01-01

    This paper introduces a spatially continuous force-based model for simulating pedestrian dynamics. The main intention of this work is the quantitative description of pedestrian movement through bottlenecks and in corridors. Measurements of flow and density at bottlenecks will be presented and compared with empirical data. Furthermore the fundamental diagram for the movement in a corridor is reproduced. The results of the proposed model show a good agreement with empirical data.

  7. EC-FORC: A New Cyclic Voltammetry Based Method for Examining Phase Transitions and Predicting Equilibrium

    OpenAIRE

    2007-01-01

    We propose a new, cyclic-voltammetry based experimental technique that can not only differentiate between discontinuous and continuous phase transitions in an adsorbate layer, but also quite accurately recover equilibrium behavior from dynamic analysis of systems with a continuous phase transition. The Electrochemical first-order reversal curve (EC-FORC) diagram for a discontinuous phase transition (nucleation and growth), such as occurs in underpotential deposition, is characterized by a neg...

  8. Geothermal exploration program, Hill Air Force Base, Davis and Weber Counties, Utah

    Energy Technology Data Exchange (ETDEWEB)

    Glenn, W.E.; Chapman, D.S.; Foley, D.; Capuano, R.M.; Cole, D.; Sibbett, B.; Ward, S.H.

    1980-03-01

    Results obtained from a program designed to locate a low- or moderate-temperature geothermal resource that might exist beneath Hill Air Force Base (AFB), Ogden, Utah are discussed. A phased exploration program was conducted at Hill AFB. Published geological, geochemical, and geophysical reports on the area were examined, regional exploration was conducted, and two thermal gradient holes were drilled. This program demonstrated that thermal waters are not present in the shallow subsurface at this site. (MHR)

  9. Environmental Assessment Building 5745, Historical Building Demolition, Barksdale Air Force Base, Louisiana

    Science.gov (United States)

    2012-12-01

    wetlands occur, and the pine-oak-hickory- maple forest , which dominates the uplands. Seven plants listed on the state rare list and ten uncommon...parks/picnic areas, FamCamp, pools, golf course Open Space 16,450 75.0 Conservation areas, forest , safety clearance/security areas, utility...easements Water 2,317 11.0 Ponds, lakes, streams, forest wetlands Total 21,802 100 BAFB Total Area Source: Barksdale Air Force Base General Plan

  10. Optimization of Rolling Force Distribution Based on Niche Genetic Algorithm in Continuous Hot Rolling Mills

    Institute of Scientific and Technical Information of China (English)

    LIU Zi-ping; LI Li-xin

    2013-01-01

    Based on the niche genetic algorithm, the intelligent and optimizing model for the rolling force distribution in hot strip mills was put forward. The research showed that the model had many advantages such as fast searching speed, high calculating pre-cision and suiting for on-line calculation. A good strip shape could be achieved by using the model and it is appropriate and practica-ble for rolling producing.

  11. Final Environmental Assessment for the California Space Center at Vandenberg Air Force Base, California

    Science.gov (United States)

    2010-06-02

    Cultural Resources Inventory, Vandenberg Air Force Base, Santa Barbara County, California Hodges et al. (2000) 2000-04 Archaeological Survey of the...VAFB Nick Pelster, Technical Director, California Space Authority Roger Root, U.S. Fish and Wildlife Service, Ventura Field Office Chris Ryan...Heritage Program. California Department of Fish and Game, Sacramento. Hodges , C.M., C.G. Lebow, and R.L. McKim. 2000. Archaeological Survey of the

  12. Environmental Assessment for the California Space Center at Vandenberg Air Force Base, California

    Science.gov (United States)

    2010-04-08

    Cultural Resources Inventory, Vandenberg Air Force Base, Santa Barbara County, California Hodges et al. (2000) 2000-04 Archaeological Survey of the...Review Laura Ornelaz, Attorney Advisor, 30 SW/JA, VAFB Nick Pelster, Technical Director, California Space Authority Roger Root, U.S. Fish and Wildlife...the terrestrial natural communities of California. Nongame Heritage Program. California Department of Fish and Game, Sacramento. Hodges , C.M., C.G

  13. The scaled-charge additive force field for amino acid based ionic liquids

    DEFF Research Database (Denmark)

    Fileti, E. E.; Chaban, V. V.

    2014-01-01

    Ionic liquids (ILs) constitute an emerging research field. New ILs involve more and more organic and inorganic ions. Amino acid based ILs (AAILs) represent a specific interest due to their evolutional connection to proteins. We report a new non-polarizable force field (FF) for the eight AAILs com...... the CHARMM36 FF with minor modifications. Compatibility between our parameters and CHARMM36 parameters is preserved. (C) 2014 Elsevier B.V. All rights reserved....

  14. Environmental Assessment for the Solar Photovoltaic Array, Eglin Air Force Base, Florida

    Science.gov (United States)

    2014-01-24

    systems. ● Sequence construction activities to limit the soil exposure for long periods of time. 5 Water Resources ● Do not alter natural flow...construction activities to limit the soil exposure for long periods of time. Management Practices Management Actions January 2014 Solar Photovoltaic Array...ENVIRONMENTAL !ASSESSMENT FOR THE SOLAR PHOTOVOLTAIC ARRAY AT EGLIN AIR FORCE BASE- OKALOOSA COUNTY, FLORIDA. I USAF - DEA, SOLAR PHOTOVOL TAlC ARRAY AT EGLIN

  15. Environmental Assessment for Mill Creek Restoration Project, Eglin Air Force Base, FL

    Science.gov (United States)

    2007-02-28

    Persons Contacted Mr. Chris Metcalf , U.S. Fish and Wildlife Service Mr Bob Miller, 96 CEG/CEVSN, Endangered Species Biologist Mr Mike Nunley, 96 CEG...currents into the center of the channel, and preventing back eddy erosion. In addition, these structures provide excellent fish habitat, maintain...bank protection and limit any back eddy erosion. 05/06 Biological Assessment Page A-13 for Mill Creek Restoration Project Eglin Air Force Base

  16. Exploration and Resource Assessment at Mountain Home Air Force Base, Idaho Using an Integrated Team Approach

    Energy Technology Data Exchange (ETDEWEB)

    Joseph C. Armstrong; Robert P. Breckenridge; Dennis L. Nielson; John W. Shervais; Thomas R. Wood

    2012-10-01

    The U.S. Air Force is facing a number of challenges as it moves into the future, one of the biggest being how to provide safe and secure energy to support base operations. A team of scientists and engineers met at Mountain Home Air Force Base near Boise, Idaho, to discuss the possibility of exploring for geothermal resources under the base. The team identified that there was a reasonable potential for geothermal resources based on data from an existing well. In addition, a regional gravity map helped identify several possible locations for drilling a new well. The team identified several possible sources of funding for this well—the most logical being to use U.S. Department of Energy funds to drill the upper half of the well and U.S. Air Force funds to drill the bottom half of the well. The well was designed as a slimhole well in accordance with State of Idaho Department of Water Resources rules and regulations. Drilling operations commenced at the Mountain Home site in July of 2011 and were completed in January of 2012. Temperatures increased gradually, especially below a depth of 2000 ft. Temperatures increased more rapidly below a depth of 5500 ft. The bottom of the well is at 5976 ft, where a temperature of about 140°C was recorded. The well flowed artesian from a depth below 5600 ft, until it was plugged off with drilling mud. Core samples were collected from the well and are being analyzed to help understand permeability at depth. Additional tests using a televiewer system will be run to evaluate orientation and directions at fractures, especially in the production zone. A final report on the well exploitation will be forthcoming later this year. The Air Force will use it to evaluate the geothermal resource potential for future private development options at Mountain Home AFB.

  17. Photophysical study of a polyoxo ethylene linked naphthalene-based fluorescent chemosensor for Mg2+ and Ca2+ detection.

    Science.gov (United States)

    Xiang, Xiaoyan; Wang, Dan; Guo, Yali; Liu, Weisheng; Qin, Wenwu

    2013-07-01

    A naphthalene-based bichromophoric fluorescent sensor 2,2'-[oxy-bis(2-oxatetramethyleneoxy)]-bis[N-(2-naphthyl)-benzamide)] (1) was synthesized and characterized. Fluorescence decay for 1 in alcoholic solvents in the region of 415-460 nm revealed bi-exponential behavior. The faster component of the decay can be attributed to the formation of dimers. Above 480 nm, besides the dimer, there is also a little excimer formation and this excimer emits at longer wavelengths than the dimer. The observation of the change of the fluorescence emission spectra upon addition of water in EtOH-water mixtures is in line with the formation of water-bridged complexes preventing excimer formation. The sensor shows an increase in fluorescence intensity upon increasing Mg(2+) or Ca(2+) concentration in EtOH because the formation of the excimer can be hindered upon complexation with Mg(2+) or Ca(2+) ions. Because of the competition between hydrated metal ions and the water-bridged complex, spectral changes by complexation with Mg(2+) or Ca(2+) in EtOH-H2O (9 : 1 v/v) are quite different from those in neat ethanol. The ground-state dissociation constant K(d) estimated for the complex with Mg(2+) or Ca(2+) was found to be around 2.0 mM in EtOH-H2O (9 : 1 v/v), which makes it suitable for the measurement of the concentrations of these ions in physiologically relevant concentration ranges.

  18. Controlling the Vaterite CaCO3 Crystal Pores. Design of Tailor-Made Polymer Based Microcapsules by Hard Templating.

    Science.gov (United States)

    Feoktistova, Natalia; Rose, Juergen; Prokopović, Vladimir Z; Vikulina, Anna S; Skirtach, Andre; Volodkin, Dmitry

    2016-05-03

    The spherical vaterite CaCO3 microcrystals are nowadays widely used as sacrificial templates for fabrication of various microcarriers made of biopolymers (e.g., proteins, nucleic acids, enzymes) due to porous structure and mild template elimination conditions. Here, we demonstrated for the first time that polymer microcarriers with tuned internal nanoarchitecture can be designed by employing the CaCO3 crystals of controlled porosity. The layer-by-layer deposition has been utilized to assemble shell-like (hollow) and matrix-like (filled) polymer capsules due to restricted and free polymer diffusion through the crystal pores, respectively. The crystal pore size in the range of few tens of nanometers can be adjusted without any additives by variation of the crystal preparation temperature in the range 7-45 °C. The temperature-mediated growth mechanism is explained by the Ostwald ripening of nanocrystallites forming the crystal secondary structure. Various techniques including SEM, AFM, CLSM, Raman microscopy, nitrogen adsorption-desorption, and XRD have been employed for crystal and microcapsule analysis. A three-dimensional model is introduced to describe the crystal internal structure and predict the pore cutoff and available surface for the pore diffusing molecules. Inherent biocompatibility of CaCO3 and a possibility to scale the porosity in the size range of typical biomacromolecules make the CaCO3 crystals extremely attractive tools for template assisted designing tailor-made biopolymer-based architectures in 2D to 3D targeted at drug delivery and other bioapplications.

  19. Hierarchical CaCO3 chromatography: a stationary phase based on biominerals.

    Science.gov (United States)

    Sato, Kosuke; Oaki, Yuya; Takahashi, Daisuke; Toshima, Kazunobu; Imai, Hiroaki

    2015-03-23

    In biomineralization, acidic macromolecules play important roles for the growth control of crystals through a specific interaction. Inspired by this interaction, we report on an application of the hierarchical structures in CaCO3 biominerals to a stationary phase of chromatography. The separation and purification of acidic small organic molecules are achieved by thin-layer chromatography and flash chromatography using the powder of biominerals as the stationary phase. The unit nanocrystals and their oriented assembly, the hierarchical structure, are suitable for the adsorption site of the target organic molecules and the flow path of the elution solvents, respectively. The separation mode is ascribed to the specific adsorption of the acidic molecules on the crystal face and the coordination of the functional groups to the calcium ions. The results imply that a new family of stationary phase of chromatography can be developed by the fine tuning of hierarchical structures in CaCO3 materials. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Analysis of a Lorentz force based vibration exciter using permanent magnets mounted on a piezoelectric stack

    Indian Academy of Sciences (India)

    Arghya Nandi; Sumanta Neogy; Sankha Bhaduri

    2011-02-01

    This work presents performance analysis of a Lorentz force based noncontact vibration exciter by mounting a couple of permanent magnets on a piezoelectric stack. A conductor is attached to the structure to be excited and is placed midway between unlike poles of a couple of permanent magnets. The permanent magnets are placed on a piezoelectric stack. This stack, because of its nano-positioning capabilities, can impart an accurate and adjustable harmonic vibratory motion to the couple of permanent magnets. The piezoelectric stack, because of its high stiffness remains uncoupled with the dynamics of the structure. Due to the relative motion between the magnets and the conductor, Lorentz force is generated within the conductor. This Lorentz force is responsible for vibration of the structure in a plane parallel to the pole faces of the magnets. This keeps the magnetic field almost independent of the vibration of the structure and the chance of the structure hitting the magnet during large vibration is totally eliminated. If the amplitude of displacement of the stack is kept constant, the non-contact excitation force in this exciter remains proportional to the excitation frequency. Though use of this exciter eliminates mass (apart from that of the conductor attached to the structure) and stiffness coupling, a known damping term gets added to that of the excited structure.

  1. Development and precision position/force control of a new flexure-based microgripper

    Science.gov (United States)

    Yang, Yi-ling; Wei, Yan-ding; Lou, Jun-qiang; Xie, Feng-ran; Fu, Lei

    2016-01-01

    This paper presents the design, modeling and position/force control of a new piezo-driven microgripper with integrated position and force sensors. The structural design of the microgripper is based on double amplification mechanisms employing the bridge-type mechanism and the parallelogram mechanism. The microgripper can generate a large gripping range and pure translation of the gripping arm. Through the pseudorigid-body-model method, theoretical models are derived. By means of several finite-element analysis simulations, the optimal structural parameters for the microgripper are acquired and the theoretical models are analyzed and validated. Furthermore, to improve the performance of the microgripper, a new hybrid position/force control scheme employing a nonlinear fuzzy logic controller combined with an incremental proportional-integral controller is presented. The control scheme is capable of regulating the position and the gripping force of the microgripper simultaneously. Experimental investigation and validation were performed and the experimental results verify the effectiveness of the developed structural design and the proposed hybrid control scheme.

  2. Novel Door-opening Method for Six-legged Robots Based on Only Force Sensing

    Science.gov (United States)

    Chen, Zhi-Jun; Gao, Feng; Pan, Yang

    2017-09-01

    Current door-opening methods are mainly developed on tracked, wheeled and biped robots by applying multi-DOF manipulators and vision systems. However, door-opening methods for six-legged robots are seldom studied, especially using 0-DOF tools to operate and only force sensing to detect. A novel door-opening method for six-legged robots is developed and implemented to the six-parallel-legged robot. The kinematic model of the six-parallel-legged robot is established and the model of measuring the positional relationship between the robot and the door is proposed. The measurement model is completely based on only force sensing. The real-time trajectory planning method and the control strategy are designed. The trajectory planning method allows the maximum angle between the sagittal axis of the robot body and the normal line of the door plane to be 45º. A 0-DOF tool mounted to the robot body is applied to operate. By integrating with the body, the tool has 6 DOFs and enough workspace to operate. The loose grasp achieved by the tool helps release the inner force in the tool. Experiments are carried out to validate the method. The results show that the method is effective and robust in opening doors wider than 1 m. This paper proposes a novel door-opening method for six-legged robots, which notably uses a 0-DOF tool and only force sensing to detect and open the door.

  3. Structure and properties of bioactive eutectic glasses based on the Ca3(PO4)2-CaSiO3-CaMg(SiO3)2 system.

    Science.gov (United States)

    Magallanes-Perdomo, M; De Aza, A H; Sobrados, I; Sanz, J; Pena, P

    2012-02-01

    Taking into account the phase equilibrium relationships within the Ca3(PO4)2-CaSiO3-CaMg(SiO3)2 ternary system, three bioactive glasses with a eutectic composition and analogous amounts of Ca3(PO4)2 (∼40 wt.%) have been prepared. The structure of the glasses was investigated by 31P and 29Si magic angle spinning nuclear magnetic resonance (MAS-NMR) spectroscopy. The glasses exhibited thermal expansion coefficients (50-600 °C) of 11.8-13.3×10(-6) °C(-1), a glass transition temperature of 790-720 °C and a softening temperature of 811-750 °C. The mechanical properties of the glasses were as follows: bending strength ∼100 MPa, Young's modulus 94-83 GPa, Vickers microhardness 7.1-4.1 GPa and toughness 0.8 MPa m1/2. The bioactive properties were discussed in terms of their structure deduced by MAS-NMR spectroscopy and the field strength of the network modifiers (Mg2+ and Ca2+). A knowledge of the glass structure was important in predicting its bioactivity. Copyright © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  4. Spatiotemporal Modeling of Urban Growth Predictions Based on Driving Force Factors in Five Saudi Arabian Cities

    Directory of Open Access Journals (Sweden)

    Abdullah F. Alqurashi

    2016-08-01

    Full Text Available This paper investigates the effect of four driving forces, including elevation, slope, distance to drainage and distance to major roads, on urban expansion in five Saudi Arabian cities: Riyadh, Jeddah, Makkah, Al-Taif and Eastern Area. The prediction of urban probabilities in the selected cities based on the four driving forces is generated using a logistic regression model for two time periods of urban change in 1985 and 2014. The validation of the model was tested using two approaches. The first approach was a quantitative analysis by using the Relative Operating Characteristic (ROC method. The second approach was a qualitative analysis in which the probable urban growth maps based on urban changes in 1985 is used to test the performance of the model to predict the probable urban growth after 2014 by comparing the probable maps of 1985 and the actual urban growth of 2014. The results indicate that the prediction model of 2014 provides a reliable and consistent prediction based on the performance of 1985. The analysis of driving forces shows variable effects over time. Variables such as elevation, slope and road distance had significant effects on the selected cities. However, distance to major roads was the factor with the most impact to determine the urban form in all five cites in both 1985 and 2014.

  5. The simulation of the half-dry stroke based on the force feedback technology

    Science.gov (United States)

    Guo, Chao; Hou, Zeng-xuan; Zheng, Shuan-zhu; Yang, Guang-qing

    2017-02-01

    A novel stroke simulation method of the Half-dry style of Chinese calligraphy based on the force feedback technology is proposed for the virtual painting. Firstly, according to the deformation of the brush when the force is exerted on it, the brush footprint between the brush and paper is calculated. The complete brush stroke is obtained by superimposing brush footprints along the painting direction, and the dynamic painting of the brush stroke is implemented. Then, we establish the half-dry texture databases and propose the concept of half-dry value by researching the main factors that affect the effects of the half-dry stroke. In the virtual painting, the half-dry texture is mapped into the stroke in real time according to the half-dry value and painting technique. A technique of texture blending based on the KM model is applied to avoid the seams while texture mapping. The proposed method has been successfully applied to the virtual painting system based on the force feedback technology. In this system, users can implement the painting in real time with a Phantom Desktop haptic device, which can effectively enhance reality to users.

  6. Integral force feedback control with input shaping: Application to piezo-based scanning systems in ECDLs

    Science.gov (United States)

    Zhang, Meng; Liu, Zhigang; Zhu, Yu; Bu, Mingfan; Hong, Jun

    2017-07-01

    In this paper, a hybrid control system is developed by integrating the closed-loop force feedback and input shaping method to overcome the problem of the hysteresis and dynamic behavior in piezo-based scanning systems and increase the scanning speed of tunable external cavity diode lasers. The flexible hinge and piezoelectric actuators are analyzed, and a dynamic model of the scanning systems is established. A force sensor and an integral controller are utilized in integral force feedback (IFF) to directly augment the damping of the piezoelectric scanning systems. Hysteresis has been effectively eliminated, but the mechanical resonance is still evident. Noticeable residual vibration occurred after the inflection points and then gradually disappeared. For the further control of mechanical resonance, based on the theory of minimum-acceleration trajectory planning, the time-domain input shaping method was developed. The turning sections of a scanning trajectory are replaced by smooth curves, while the linear sections are retained. The IFF method is combined with the input shaping method to control the non-linearity and mechanical resonance in high-speed piezo-based scanning systems. Experiments are conducted, and the results demonstrate the effectiveness of the proposed control approach.

  7. Study on condition of CaO2-based Fenton reaction by methylene blue spectrophotometric method%亚甲基蓝光度法研究基于CaO2的Fenton反应条件

    Institute of Scientific and Technical Information of China (English)

    刘娇; 孟范平; 王震宇; 刘启元

    2011-01-01

    The potential of calcium peroxide (CaO2) as a source of hydrogen peroxide (H2O2) in Fenton oxidation has been gradually taken note. In order to understand the characteristics of CaO2-based Fenton reactions, experiments were conducted using methylene blue spectrophotometric method to investigate effect of catalyst type, initial pH, CaO2 dose, molar ratio of catalyst to CaO2 (?Fe/?cao2 )? And phosphate buffer concentration on production of hydroxyl radicals (HO ? ). The results showed that under the experimental conditions Fez+ had better catalytic ability than Fe3+ and Cu2+. The optimal Fenton reaction conditions were; Fe2+ as catalyst, initial buffer pH = 4, CaO2 dose 1 mmol ? L"1 , wF,/?cao2 = 1/5, phosphate buffer concentration 40 mmol ? L"1. It was also indicated that the release of H2O2 and Fenton reaction were regulated by the dissolution process of CaO2 that could be a potential substitute for H2O2 in in-situ Fenton oxidations, because of decrease of H2O2 loss as well as negative impact of Fenton processes on the environment.%CaO2作为原位Fenton氧化修复中H2O2持续供源的作用逐渐受到关注.利用亚甲基蓝分光光度法评价了基于CaO2的Fenton反应中催化剂种类、初始pH值、CaO2用最、催化剂和CaO2比例、磷酸缓冲溶液浓度对羟基自由基(HO·)产率的影响.结果表明,采用Fe2作为催化剂,在pH值为4、CaO2用量为1 mmo1·L-1,催化剂CaO2摩尔比(nFe/nCaO2.)为1/5、磷酸缓冲溶液浓度为40 mmol·L-1时HO·产率较高,Fe2+催化作用最显著.CaO2溶解过程对H2O2的释放和Fenton反应起到一定调节作用,以CaO2取代H2O2可减少氧化剂的流失及其对环境产生的不利影响.

  8. Force decomposition in robot force control

    Science.gov (United States)

    Murphy, Steve H.; Wen, John T.

    1991-01-01

    The unit inconsistency in force decomposition has motivated an investigation into the force control problem in multiple-arm manipulation. Based on physical considerations, it is argued that the force that should be controlled is the internal force at the specified frame in the payload. This force contains contributions due to both applied forces from the arms and the inertial force from the payload and the arms. A least-squares scheme free of unit inconsistency for finding this internal force is presented. The force control issue is analyzed, and an integral force feedback controller is proposed.

  9. (Environmental investigation of ground water contamination at Wright- Patterson Air Force Base, Ohio)

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This Health and Safety Plan (HSP) was developed for the Environmental Investigation of Ground-water Contamination Investigation at Wright-Patterson Air Force Base near Dayton, Ohio, based on the projected scope of work for the Phase 1, Task 4 Field Investigation. The HSP describes hazards that may be encountered during the investigation, assesses the hazards, and indicates what type of personal protective equipment is to be used for each task performed. The HSP also addresses the medical monitoring program, decontamination procedures, air monitoring, training, site control, accident prevention, and emergency response.

  10. Building a multi-walled carbon nanotube-based mass sensor with the atomic force microscope

    DEFF Research Database (Denmark)

    Mateiu, Ramona Valentina; Kuhle, A.; Marie, Rodolphe Charly Willy;

    2005-01-01

    We report an approach for building a mass sensor based on multi-walled carbon nanotubes (MWCNT). We propose a method with a great potential for the positioning of MWCNTs based on self-assembly onto patterned hydrophilic areas. For the experiments ultra flat mica substrates covered with gold...... are used. The gold substrate is first covered with hydrophobic thiol molecules: octadecanthiol. The octadecanthiol molecules are then selectively removed from small areas by nanoshaving the gold substrate with the tip of an atomic force microscope (AFM) operating in contact mode. Hydrophilic thiols (2...

  11. Final Environmental Impact Statement. Potential Exploration, Development, and Production of Oil and Gas Resources, Vandenberg Air Force Base, CA

    Science.gov (United States)

    1987-12-18

    and COMPLEX N Gaussian dispersion moodels for complex terr ain appflca- and the terrain treatment optia: flons; have been made, avatilable by EPA...concentrations wm real wins (1099 data pomms ) Sepiemoer 1983 Volume 33. No 9 867C & .R-97 ( 3 ,)i .’ ] 99 99 -99 /n 9o ,99 9 99 990 99 Cormolix I Cole.x If

  12. Environmental Impact Analysis Process, Environmental Assessment Space Test Experiments Platform Mission 3, Vandenberg Air Force Base, CA

    Science.gov (United States)

    2007-11-02

    Kosmos 954, which scattered pieces in northern Canada in 1978, and the National Aeronautics and Space Administration (NASA) Skylab satellite, which...cleanup has been set with the January 1978 burn up and disintegration of the Soviet Kosmos 954 satellite (Baker, 1989). The Kosmos 954 was an 3-13 ocean

  13. Environmental Impact Analysis Process, Environmental Assessment Space Test Experiments Platform Mission 1, Vandenberg Air Force Base, CA

    Science.gov (United States)

    2007-11-02

    the earth’s atmosphere. Well-known examples include the Russian Kosmos 954, which scattered pieces in northern Canada in 1978, and the National... Kosmos 954 satellite (Baker, 1989). The Kosmos 954 was an ocean surveillance satellite containing a nuclear power source fueled by about 50 kg of

  14. A statistical method of identifying interactions in neuron-glia systems based on functional multicell Ca2+ imaging.

    Directory of Open Access Journals (Sweden)

    Ken Nakae

    2014-11-01

    Full Text Available Crosstalk between neurons and glia may constitute a significant part of information processing in the brain. We present a novel method of statistically identifying interactions in a neuron-glia network. We attempted to identify neuron-glia interactions from neuronal and glial activities via maximum-a-posteriori (MAP-based parameter estimation by developing a generalized linear model (GLM of a neuron-glia network. The interactions in our interest included functional connectivity and response functions. We evaluated the cross-validated likelihood of GLMs that resulted from the addition or removal of connections to confirm the existence of specific neuron-to-glia or glia-to-neuron connections. We only accepted addition or removal when the modification improved the cross-validated likelihood. We applied the method to a high-throughput, multicellular in vitro Ca2+ imaging dataset obtained from the CA3 region of a rat hippocampus, and then evaluated the reliability of connectivity estimates using a statistical test based on a surrogate method. Our findings based on the estimated connectivity were in good agreement with currently available physiological knowledge, suggesting our method can elucidate undiscovered functions of neuron-glia systems.

  15. A Statistical Method of Identifying Interactions in Neuron–Glia Systems Based on Functional Multicell Ca2+ Imaging

    Science.gov (United States)

    Nakae, Ken; Ikegaya, Yuji; Ishikawa, Tomoe; Oba, Shigeyuki; Urakubo, Hidetoshi; Koyama, Masanori; Ishii, Shin

    2014-01-01

    Crosstalk between neurons and glia may constitute a significant part of information processing in the brain. We present a novel method of statistically identifying interactions in a neuron–glia network. We attempted to identify neuron–glia interactions from neuronal and glial activities via maximum-a-posteriori (MAP)-based parameter estimation by developing a generalized linear model (GLM) of a neuron–glia network. The interactions in our interest included functional connectivity and response functions. We evaluated the cross-validated likelihood of GLMs that resulted from the addition or removal of connections to confirm the existence of specific neuron-to-glia or glia-to-neuron connections. We only accepted addition or removal when the modification improved the cross-validated likelihood. We applied the method to a high-throughput, multicellular in vitro Ca2+ imaging dataset obtained from the CA3 region of a rat hippocampus, and then evaluated the reliability of connectivity estimates using a statistical test based on a surrogate method. Our findings based on the estimated connectivity were in good agreement with currently available physiological knowledge, suggesting our method can elucidate undiscovered functions of neuron–glia systems. PMID:25393874

  16. Simulation of bidirectional pedestrian flow in transfer station corridor based on multi forces

    Institute of Scientific and Technical Information of China (English)

    周雪梅; 纪翔峰; 黄凰; 杨晓光

    2014-01-01

    A good understanding of pedestrian movement in the transfer corridor is vital for the planning and design of the station, especially for efficiency and safety.A multi-force vector grid model was presented to simulate the movement of bidirectional pedestrian flow based on cellular automata and forces between pedestrians. The model improves rule-based characteristics of cellular automata, details forces between pedestrians and solves pedestrian collisions by a several-step updating method to simulate pedestrian movements. Two general scenarios in corridor were simulated. One is bidirectional pedestrian flow simulation with isolation facility, and the other is bidirectional pedestrian flow simulation without isolation facility, where there exists disturbance in the middle. Through simulation, some facts can be seen that pedestrians in the case with isolation facility have the largest speed and pedestrians in the case without isolation facility have the smallest speed; pedestrians in the case of unidirectional flow have the largest volume and pedestrians in the case of without isolation facility have the smallest volume.

  17. A low cost grip transducer based instrument to quantify fingertip touch force.

    Science.gov (United States)

    Boukhenous, Samir; Attari, Mokhtar

    2007-01-01

    In this paper, a transducer based instrument for fingertip touch force is developed. As a diagnostic tool, the system was coupled with an EMG analog signal processor, which is considered as the main basis of evaluation for motor function impairment. A software program is developed to analyze EMG signal during fingertips effort to obtain valid characteristic parameters with spectral analysis. These parameters are associated with a low cost grip transducer based on Hall Effect component developed for the improvement of fingertip movement during holding objects or training exercises. Thus, the changes on each sensor signal can be detected and monitored with the software interface. The output signal and the EMG analog processor are feeding a high resolution data acquisition system of National Instrument. Preliminary experimental tests have been carried out for the fingertip force grasping according to the Adductor Pollicis muscle (AdP) for controlling the adductive motion of the thumb. The experimental results show that the changes of dynamic fingertip force affect the muscle.

  18. [The motive force of evolution based on the principle of organismal adjustment evolution.].

    Science.gov (United States)

    Cao, Jia-Shu

    2010-08-01

    From the analysis of the existing problems of the prevalent theories of evolution, this paper discussed the motive force of evolution based on the knowledge of the principle of organismal adjustment evolution to get a new understanding of the evolution mechanism. In the guide of Schrodinger's theory - "life feeds on negative entropy", the author proposed that "negative entropy flow" actually includes material flow, energy flow and information flow, and the "negative entropy flow" is the motive force for living and development. By modifying my own theory of principle of organismal adjustment evolution (not adaptation evolution), a new theory of "regulation system of organismal adjustment evolution involved in DNA, RNA and protein interacting with environment" is proposed. According to the view that phylogenetic development is the "integral" of individual development, the difference of negative entropy flow between organisms and environment is considered to be a motive force for evolution, which is a new understanding of the mechanism of evolution. Based on such understanding, evolution is regarded as "a changing process that one subsystem passes all or part of its genetic information to the next generation in a larger system, and during the adaptation process produces some new elements, stops some old ones, and thereby lasts in the larger system". Some other controversial questions related to evolution are also discussed.

  19. Land subsidence and problems affecting land use at Edwards Air Force Base and vicinity, California, 1990

    Science.gov (United States)

    Blodgett, James C.; Williams, J. S.

    Land subsidence in Antelope Valley, which includes Edwards Air Force Base, was first reported in the 1950's; by 1967, about 200 square miles of Antelope Valley were affected by as much as 2 feet of subsidence. The purpose of the report is to present the results to date of recent studies done by the U.S. Geological Survey, in cooperation with the U.S. Department of the Air Force, to determine the cause and areal extent of land subsidence and surface deformation on Rogers Lakebed and vicinity, and the effects of surface deformation on runways used for aircraft landings at Edwards AFB in southern California. Because of the time-related effects of land subsidence, several years of data collection will be needed to establish subsidence trends and evaluate those factors causing land subsidence.

  20. Modeling of Drilling Forces Based on Twist Drill Point Angles Using Multigene Genetic Programming

    Directory of Open Access Journals (Sweden)

    Myong-Il Kim

    2016-01-01

    Full Text Available The mathematical model was developed for predicting the influence of the drill point angles on the cutting forces in drilling with the twist drills, which was used to optimize those angles for reducing drilling forces. The approach was based on multigene genetic programming, for the training data, the grinding tests of twist drill were firstly conducted for the different drill point angles in Biglide parallel machine, and then drilling tests were performed on carbon fiber reinforced plastics using the grinded drills. The effectiveness of the proposed approach was verified through comparing with published data. It was found that the proposed model agreed well with the experimental data and was useful for improving the performance of twist drill.

  1. Central-force decomposition of spline-based modified embedded atom method potential

    Science.gov (United States)

    Winczewski, S.; Dziedzic, J.; Rybicki, J.

    2016-10-01

    Central-force decompositions are fundamental to the calculation of stress fields in atomic systems by means of Hardy stress. We derive expressions for a central-force decomposition of the spline-based modified embedded atom method (s-MEAM) potential. The expressions are subsequently simplified to a form that can be readily used in molecular-dynamics simulations, enabling the calculation of the spatial distribution of stress in systems treated with this novel class of empirical potentials. We briefly discuss the properties of the obtained decomposition and highlight further computational techniques that can be expected to benefit from the results of this work. To demonstrate the practicability of the derived expressions, we apply them to calculate stress fields due to an edge dislocation in bcc Mo, comparing their predictions to those of linear elasticity theory.

  2. An Atomic Force Microscopy based investigation of specific biomechanical properties for various types of neuronal cells

    Science.gov (United States)

    Spedden, Elise; White, James; Kaplan, David; Staii, Cristian

    2012-02-01

    Here we describe the use of Atomic Force Microscope (AFM) based techniques to characterize and explore the influence of biochemical and biomechanical cues on the growth and interaction of neuronal cells with surrounding guidance factors. Specifically, we use AFM topography and AFM force spectroscopy measurements to systematically investigate the morphology, elasticity, and real time growth of neuronal processes in the presence of different types of extracellular matrix proteins and growth factors. We therefore create a series of systems containing specified neuron densities where the type of the underlying growth promoting protein is different from sample to sample. For each system we measure key biomechanical parameters related to neuronal growth such as height and elastic modulus at multiple growth points on several types of neurons. We show that systematic measurements of these parameters yield fundamental information about the role played by substrate-plated guidance factors in determining elastic and morphological properties of neurons during growth.

  3. A Force-Based Grid Manipulator for ALE Calculations in a Lobe Pump

    Institute of Scientific and Technical Information of China (English)

    John Vande Voorde; Jan Vierendeels; Erik Dick

    2003-01-01

    In this paper, a time-dependant calculation of flow in a lobe pump is presented. Calculations are performed using the arbitrary Lagrangean Eulerean (ALE) method. A grid manipulator is needed to move the nodes between time steps. The used grid manipulator is based on the pseudo-force idea. This means that each node is fictitiously connected with its 8 neighbours via fictitious springs. The equilibrium of the resulting pseudo spring forces defines the altered position of the nodes. The grid manipulator was coupled with a commercial flow solver and the whole was tested on the flow through a three-lobe lobe pump. Results were obtained for a rotational speed of 460 rpm and incompressible silicon oil as fluid.

  4. Radar Scan Strategies for the Patrick Air Force Base Weather Surveillance Radar, Model-74C, Replacement

    Science.gov (United States)

    Short, David

    2008-01-01

    The 45th Weather Squadron (45 WS) is replacing the Weather Surveillance Radar, Model 74C (WSR-74C) at Patrick Air Force Base (PAFB), with a Doppler, dual polarization radar, the Radtec 43/250. A new scan strategy is needed for the Radtec 43/250, to provide high vertical resolution data over the Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS) launch pads, while taking advantage of the new radar's advanced capabilities for detecting severe weather phenomena associated with convection within the 45 WS area of responsibility. The Applied Meteorology Unit (AMU) developed several scan strategies customized for the operational needs of the 45 WS. The AMU also developed a plan for evaluating the scan strategies in the period prior to operational acceptance, currently scheduled for November 2008.

  5. Passive microrheology of soft materials with atomic force microscopy: A wavelet-based spectral analysis

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Torres, C.; Streppa, L. [CNRS, UMR5672, Laboratoire de Physique, Ecole Normale Supérieure de Lyon, 46 Allée d' Italie, Université de Lyon, 69007 Lyon (France); Arneodo, A.; Argoul, F. [CNRS, UMR5672, Laboratoire de Physique, Ecole Normale Supérieure de Lyon, 46 Allée d' Italie, Université de Lyon, 69007 Lyon (France); CNRS, UMR5798, Laboratoire Ondes et Matière d' Aquitaine, Université de Bordeaux, 351 Cours de la Libération, 33405 Talence (France); Argoul, P. [Université Paris-Est, Ecole des Ponts ParisTech, SDOA, MAST, IFSTTAR, 14-20 Bd Newton, Cité Descartes, 77420 Champs sur Marne (France)

    2016-01-18

    Compared to active microrheology where a known force or modulation is periodically imposed to a soft material, passive microrheology relies on the spectral analysis of the spontaneous motion of tracers inherent or external to the material. Passive microrheology studies of soft or living materials with atomic force microscopy (AFM) cantilever tips are rather rare because, in the spectral densities, the rheological response of the materials is hardly distinguishable from other sources of random or periodic perturbations. To circumvent this difficulty, we propose here a wavelet-based decomposition of AFM cantilever tip fluctuations and we show that when applying this multi-scale method to soft polymer layers and to living myoblasts, the structural damping exponents of these soft materials can be retrieved.

  6. Influences of nuclear containment radius on the aircraft impact force based on the Riera function

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, T.; Wu, H., E-mail: abrahamhao@126.com; Fang, Q.; Gong, Z.M.

    2015-11-15

    Highlights: • A fine aircraft model of A320 was built and verified by available limited prototype impacting tests. • The influences of aircraft longitudinal crushing strength on the impact process were analyzed. • The influences of NPP containment radius on the impact force were numerically studied. • The Riera function was modified by considering the radius effect of NPP containment. - Abstract: The aircraft impact force directly influences the local failure and global response of the nuclear power plant (NPP) containment, while the existing theoretical models and the field tests were almost based on the flat target. In order to analyze the radius effect of the circular sectional containment on the impact force, a fine FE model of the commercial aircraft A320 was established and validated by the available limited full-scale F-4 Phantom impact experiment. In order to determine the force to crush the A320 FE model, the influences of aircraft longitudinal crushing strength on the impact process were analyzed based on the Riera function. Considering the containment decaying effect to aircraft impact velocity, the impact impulse was theoretically calculated, while the influences of the losses of mass and energy were not included. The numerical simulations of A320 aircrafts impacting on simplified NPP containments with different radii were conducted, which could well reproduce the airframe crushing and debris scattering. By comparison of the simulated impact impulses and the calculation values by the Riera function, the coefficients corresponding to different containment radii are derived and a fitting formula is obtained. Finally, an improved Riera function dependent on the dimensionless ratio of nuclear containment radius and aircraft wingspan is proposed.

  7. Development of a novel liquid crystal based cell traction force transducer system.

    Science.gov (United States)

    Soon, C F; Youseffi, M; Berends, R F; Blagden, N; Denyer, M C T

    2013-01-15

    Keratinocyte traction forces play a crucial role in wound healing. The aim of this study was to develop a novel cell traction force (CTF) transducer system based on cholesteryl ester liquid crystals (LC). Keratinocytes cultured on LC induced linear and isolated deformation lines in the LC surface. As suggested by the fluorescence staining, the deformation lines appeared to correlate with the forces generated by the contraction of circumferential actin filaments which were transmitted to the LC surface via the focal adhesions. Due to the linear viscoelastic behavior of the LC, Hooke's equation was used to quantify the CTFs by associating Young's modulus of LC to the cell induced stresses and biaxial strain in forming the LC deformation. Young's modulus of the LC was profiled by using spherical indentation and determined at approximately 87.1±17.2kPa. A new technique involving cytochalasin-B treatment was used to disrupt the intracellular force generating actin fibers, and consequently the biaxial strain in the LC induced by the cells was determined. Due to the improved sensitivity and spatial resolution (∼1μm) of the LC based CTF transducer, a wide range of CTFs was determined (10-120nN). These were found to be linearly proportional to the length of the deformations. The linear relationship of CTF-deformations was then applied in a bespoke CTF mapping software to estimate CTFs and to map CTF fields. The generated CTF map highlighted distinct distributions and different magnitude of CTFs were revealed for polarized and non-polarized keratinocytes. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. EMRE Is a Matrix Ca(2+) Sensor that Governs Gatekeeping of the Mitochondrial Ca(2+) Uniporter.

    Science.gov (United States)

    Vais, Horia; Mallilankaraman, Karthik; Mak, Don-On Daniel; Hoff, Henry; Payne, Riley; Tanis, Jessica E; Foskett, J Kevin

    2016-01-26

    The mitochondrial uniporter (MCU) is an ion channel that mediates Ca(2+) uptake into the matrix to regulate metabolism, cell death, and cytoplasmic Ca(2+) signaling. Matrix Ca(2+) concentration is similar to that in cytoplasm, despite an enormous driving force for entry, but the mechanisms that prevent mitochondrial Ca(2+) overload are unclear. Here, we show that MCU channel activity is governed by matrix Ca(2+) concentration through EMRE. Deletion or charge neutralization of its matrix-localized acidic C terminus abolishes matrix Ca(2+) inhibition of MCU Ca(2+) currents, resulting in MCU channel activation, enhanced mitochondrial Ca(2+) uptake, and constitutively elevated matrix Ca(2+) concentration. EMRE-dependent regulation of MCU channel activity requires intermembrane space-localized MICU1, MICU2, and cytoplasmic Ca(2+). Thus, mitochondria are protected from Ca(2+) depletion and Ca(2+) overload by a unique molecular complex that involves Ca(2+) sensors on both sides of the inner mitochondrial membrane, coupled through EMRE.

  9. Interparticle force based methodology for prediction of cohesive powder flow properties

    Science.gov (United States)

    Esayanur, Madhavan Sujatha Sarma

    The transport and handling of powders are key areas in the process industry that have a direct impact on the efficiency and/or the quality of the finished product. A lack of fundamental understanding of powder flow properties as a function of operating variables such as relative humidity, and particle size, leading to problems such as arching, rat-holing and segregation, is one the main causes for unscheduled down times in plant operation and loss of billions of dollars in revenues. Most of the current design strategies and characterization techniques for industrial powders are based on a continuum approach similar to the field of soil mechanics. Due to an increase in complexity of the synthesis process and reduction in size of powders to the nanoscale, the surface properties and inter particle forces play a significant role in determining the flow characteristics. The use of ensemble techniques such as direct shear testing to characterize powders are no longer adequate due to lack of understanding of the changes in the property of powders as a function of the major operating variables such as relative humidity, temperature etc. New instrumentation or techniques need to be developed to reliably characterize powder flow behavior. Simultaneously, scalability of the current models to predict powder flow needs to be revisited. Specifically, this study focuses on the development of an inter particle force based model for predicting the unconfined yield strength of cohesive powders. To understand the role of interparticle forces in determining the strength of cohesive powders, the particle scale interactions were characterized using Atomic Force Microscopy (AFM), contact angle, surface tension, and coefficient of friction. The bulk scale properties such as unconfined yield strength, packing structure, and size of the shear zone were also investigated. It was determined that an interparticle force based model incorporating the effect of particle size and packing structure

  10. Efficient burst mode amplifier for ultra-short pulses based on cryogenically cooled Yb³⁺:CaF₂.

    Science.gov (United States)

    Körner, Jörg; Hein, Joachim; Liebetrau, Hartmut; Seifert, Reinhard; Klöpfel, Diethard; Kahle, Martin; Loeser, Markus; Siebold, Mathias; Schramm, Ulrich; Kaluza, Malte C

    2013-11-18

    We present a novel approach for the amplification of high peak power femtosecond laser pulses at a high repetition rate. This approach is based on an all-diode pumped burst mode laser scheme. In this scheme, pulse bursts with a total duration between 1 and 2 ms are be generated and amplified. They contain 50 to 2000 individual pulses equally spaced in time. The individual pulses have an initial duration of 350 fs and are stretched to 50 ps prior to amplification. The amplifier stage is based on Yb3+:CaF2 cooled to 100 K. In this amplifier, a total output energy in excess of 600 mJ per burst at a repetition rate of 10 Hz is demonstrated. For lower repetition rates the total output energy per burst can be scaled up to 915 mJ using a longer pump duration. This corresponds to an efficiency as high as 25% of extracted energy from absorbed pump energy. This is the highest efficiency, which has so far been demonstrated for a pulsed Yb3+:CaF2 amplifier.

  11. Weather resistance of CaSO4 ṡ 1/2H2O-based sand-fixation material

    Science.gov (United States)

    Liu, Xin; Tie, Shengnian

    2017-07-01

    Searching for an economical and effective sand-fixing material and technology is of great importance in Northwest China. This paper described the use of a semihydrated gypsum-(CaSO4 ṡ 1/2H2O-)based composite as a sand-fixing material. Its morphology and composition were characterized by SEM, and its water resistance, freezing-thawing resistance and wind erosion resistance were tested in the field. The results indicated that semihydrated gypsum-(CaSO4 ṡ 1/2H2O-)based sand-fixing composite has good water resistance and water-holding capacity. Its strength is maintained at 1.42 MPa after 50 freezing and thawing cycles, and its wind erosion increases with increasing wind speed and slope. Its compressive strength starts to decrease after nine months of field tests with no change in appearance, but it still satisfies the requirements of fixation technology. This sand-fixing material should have wide application owing to its good weather resistance.

  12. 2017 Annual Terrestrial Sampling Plan for Sandia National Laboratories/New Mexico on Kirtland Air Force Base

    Energy Technology Data Exchange (ETDEWEB)

    Griffith, Stacy R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-02-01

    The 2017 Annual Terrestrial Sampling Plan for Sandia National Laboratories/New Mexico on Kirtland Air Force Base has been prepared in accordance with the “Letter of Agreement Between Department of Energy, National Nuclear Security Administration, Sandia Field Office (DOE/NNSA/SFO) and 377th Air Base Wing (ABW), Kirtland Air Force Base (KAFB) for Terrestrial Sampling” (signed January 2017), Sandia National Laboratories, New Mexico (SNL/NM). The Letter of Agreement requires submittal of an annual terrestrial sampling plan.

  13. Patrick Air Force Base integrated resource assessment. Volume 2, Baseline detail

    Energy Technology Data Exchange (ETDEWEB)

    Wahlstrom, R.R.; King, D.A.; Parker, S.A.; Sandusky, W.F.

    1993-08-01

    The US Air Force has tasked the Pacific Northwest Laboratory (PNL), in support of the US Department of Energy (DOE) Federal Energy Management Program (FEMP), to assess energy use at Patrick Air Force Base (AFB). The information obtained from this assessment will be used in identifying energy resource opportunities to reduce overall energy consumption on the base. The primary focus of this report is to assess the current baseline energy consumption at Patrick AFB. It is a comparison report to Volume 1, the Executive Summary, and Volume 3, the Resource Assessment. This assessment requires that information be obtained and characterized for buildings, utilities, energy sources, energy uses, and load profile information to be used to improve the characterization of energy use on the base. The characteristics of electricity, natural gas, and No. 2 fuel oil are analyzed for on-base facilities and housing. The assessment examines basic regional information used to determine energy-use intensity (EUI) values for Patrick AFB facilities by building, fuel type, and energy end use. It also provides a summary of electricity consumption from Florida Power and Light Company (FPL) metered data for 1985-1991. Load profile information obtained from FPL data is presented for the north and south substations for the four seasons of the year, including weekdays and weekends.

  14. Fall 1994 wildlife and vegetation survey, Norton Air Force Base, California

    Energy Technology Data Exchange (ETDEWEB)

    1994-12-15

    The fall 1994 wildlife and vegetation surveys were completed October 3-7, 1994, at Norton Air Force Base (AFB), California. Two biologists from CDM Federal Programs, the U.S. Environmental Protection Agency (EPA) regional biologist and the Oak Ridge National Laboratory (ORNL) lead biologist conducted the surveys. A habitat assessment of three Installation Restoration Project (IRP) sites at Norton Air Force Base was also completed during the fall survey period. The IRP sites include: Landfill No. 2 (Site 2); the Industrial Wastewater Treatment Plant (IWTP) area; and Former Fire Training Area No. 1 (Site 5). The assessments were designed to qualitatively characterize the sites of concern, identify potential ecological receptors, and provide information for Remedial Design/Remedial Action activities. A Reference Area (Santa Ana River Wash) and the base urban areas were also characterized. The reference area assessment was performed to provide a baseline for comparison with the IRP site habitats. The fall 1994 survey is the second of up to four surveys that may be completed. In order to develop a complete understanding of all plant and animal species using the base, these surveys were planned to be conducted over four seasons. Species composition can vary widely during the course of a year in Southern California, and therefore, seasonal surveys will provide the most complete and reliable data to address changes in habitat structure and wildlife use of the site. Subsequent surveys will focus on seasonal wildlife observations and a spring vegetation survey.

  15. Groundwater level and nitrate concentration trends on Mountain Home Air Force Base, southwestern Idaho

    Science.gov (United States)

    Williams, Marshall L.

    2014-01-01

    Mountain Home Air Force Base in southwestern Idaho draws most of its drinking water from the regional aquifer. The base is located within the State of Idaho's Mountain Home Groundwater Management Area and is adjacent to the State's Cinder Cone Butte Critical Groundwater Area. Both areas were established by the Idaho Department of Water Resources in the early 1980s because of declining water levels in the regional aquifer. The base also is listed by the Idaho Department of Environmental Quality as a nitrate priority area. The U.S. Geological Survey, in cooperation with the U.S. Air Force, began monitoring wells on the base in 1985, and currently monitors 25 wells for water levels and 17 wells for water quality, primarily nutrients. This report provides a summary of water-level and nitrate concentration data collected primarily between 2001 and 2013 and examines trends in those data. A Regional Kendall Test was run to combine results from all wells to determine an overall regional trend in water level. Groundwater levels declined at an average rate of about 1.08 feet per year. Nitrate concentration trends show that 3 wells (18 percent) are increasing in nitrate concentration trend, 3 wells (18 percent) show a decreasing nitrate concentration trend, and 11 wells (64 percent) show no nitrate concentration trend. Six wells (35 percent) currently exceed the U.S. Environmental Protection Agency's maximum contaminant limit of 10 milligrams per liter for nitrate (nitrite plus nitrate, measured as nitrogen).

  16. The Development of a Scientific Evaluation System of Force-on-Force (FOF) Exercise for Performance-based Regulation in Nuclear Security

    Energy Technology Data Exchange (ETDEWEB)

    Koh, Moonsung; Jung, Myungtak [Korea Institute of Nuclear Nonproliferation and Control, Daejeon (Korea, Republic of)

    2015-05-15

    A terrorist attack or sabotage at a nuclear facility could lead result in a great amount of loss of life and social chaos, in addition to serious radiological damage. As threats have been evolved more intelligent, divergent, advanced, the international societies including IAEA encourage for all member states to establish the performance-based regulation using Forceon- Force (FOF) exercise, computer simulation. Consequently, the performance evaluation for physical protection at nuclear facilities should focus on properly reacting to threat scenarios. Physical protection should also include detecting, blocking, delaying, interrupting including the human and technical factors the adversary having malicious intention of the realistic main threat element before he accomplishes the goal based on Design Basis Threat (DBT). After the completion of the FOF evaluation system, KINAC will evaluate, and later strengthen its overall security program in response to changes in the threat environment, technological advancements, and lessons learned. As a result, substantial improvements to a nuclear facility security can be predicted. These improvements will focus on a plant security force, physical barriers, intrusion detection systems, surveillance systems, and access controls. Through the building a Force-on-Force scientific evaluation system, KINAC will establish an efficient physical protection implementation system for nuclear energy facilities.

  17. A new (Ba, Ca) (Ti, Zr)O3 based multiferroic composite with large magnetoelectric effect

    Science.gov (United States)

    Naveed-Ul-Haq, M.; Shvartsman, Vladimir V.; Salamon, Soma; Wende, Heiko; Trivedi, Harsh; Mumtaz, Arif; Lupascu, Doru C.

    2016-01-01

    The lead-free ferroelectric 0.5Ba(Zr0.2Ti0.8)O3 − 0.5(Ba0.7Ca0.3)TiO3 (BCZT) is a promising component for multifunctional multiferroics due to its excellent room temperature piezoelectric properties. Having a composition close to the polymorphic phase boundary between the orthorhombic and tetragonal phases, it deserves a case study for analysis of its potential for modern electronics applications. To obtain magnetoelectric coupling, the piezoelectric phase needs to be combined with a suitable magnetostrictive phase. In the current article, we report on the synthesis, dielectric, magnetic, and magnetoelectric characterization of a new magnetoelectric multiferroic composite consisting of BCZT as a piezoelectric phase and CoFe2O4 (CFO) as the magnetostrictive phase. We found that this material is multiferroic at room temperature and manifests a magnetoelectric effect larger than that of BaTiO3 −CoFe2O4 bulk composites with similar content of the ferrite phase. PMID:27555563

  18. A new (Ba, Ca) (Ti, Zr)O3 based multiferroic composite with large magnetoelectric effect

    Science.gov (United States)

    Naveed-Ul-Haq, M.; Shvartsman, Vladimir V.; Salamon, Soma; Wende, Heiko; Trivedi, Harsh; Mumtaz, Arif; Lupascu, Doru C.

    2016-08-01

    The lead-free ferroelectric 0.5Ba(Zr0.2Ti0.8)O3 - 0.5(Ba0.7Ca0.3)TiO3 (BCZT) is a promising component for multifunctional multiferroics due to its excellent room temperature piezoelectric properties. Having a composition close to the polymorphic phase boundary between the orthorhombic and tetragonal phases, it deserves a case study for analysis of its potential for modern electronics applications. To obtain magnetoelectric coupling, the piezoelectric phase needs to be combined with a suitable magnetostrictive phase. In the current article, we report on the synthesis, dielectric, magnetic, and magnetoelectric characterization of a new magnetoelectric multiferroic composite consisting of BCZT as a piezoelectric phase and CoFe2O4 (CFO) as the magnetostrictive phase. We found that this material is multiferroic at room temperature and manifests a magnetoelectric effect larger than that of BaTiO3 -CoFe2O4 bulk composites with similar content of the ferrite phase.

  19. Study on soil solidification based on microbiological precipitation of CaCO3

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The soil solidifying technology started booming from the 1940s and formed an integrated cross-discipline.This paper aimed to study the effect and mechanism of soil solidification by microorganisms.Soil specimens treated by different methods were designed.Then the compressive strengths of these specimens on day 7 were tested and the situ bacteria culturing technique in soil was investigated.Finally the mechanism of soil solidification by microorganisms was explored according to the decomposition rate of substrate,pH value and the SEM and XRD analysis.Experimental results showed that the soil could be solidified by filling enhancement and precipitation of microorganisms.The compressive strength increased with bacteria A but decreased with substrate B,and soil specimen got a higher strength with bacteria situ cultured.The suitable pH value for bacteria A was 8–9,and the delay of lime addition could make substrate decomposition more completely,lower the influence by the existence of substrate,and improve the strength.In XRD and SEM images,precipitation of CaCO3 could be speculated.

  20. Potentiometric surfaces of the Arnold Engineering Development Complex Area, Arnold Air Force Base, Tennessee, May and September 2011

    Science.gov (United States)

    Haugh, Connor J.; Robinson, John A.

    2016-01-29

    Arnold Air Force Base occupies about 40,000 acres in Coffee and Franklin Counties, Tennessee. The primary mission of Arnold Air Force Base is to provide risk-reduction information in the development of aerospace products through test and evaluation. This mission is achieved in part through test facilities at Arnold Engineering Development Complex (AEDC), which occupies about 4,000 acres in the center of Arnold Air Force Base. Arnold Air Force Base is underlain by gravel and limestone aquifers, the most productive of which is the Manchester aquifer. Several volatile organic compounds, primarily chlorinated solvents, have been identified in the groundwater at Arnold Air Force Base. In 2011, the U.S. Geological Survey, in cooperation with the U.S. Air Force, Arnold Air Force Base, completed a study of groundwater flow focused on the Arnold Engineering Development Complex area. The Arnold Engineering Development Complex area is of particular concern because within this area (1) chlorinated solvents have been identified in the groundwater, (2) the aquifers are dewatered around below-grade test facilities, and (3) there is a regional groundwater divide.

  1. Rehabilitation for hemiplegia using an upper limb training system based on a force direction.

    Science.gov (United States)

    Ogata, Kunihiro; Hirabayashi, Yuto; Kubota, Keisuke; Hasegawa, Yuri; Tsuji, Toshiaki

    2017-07-01

    Hemiplegia patients have complete paralysis of half their body, and encounter many challenges in living an independent life. Rehabilitation of the lower body is more important than that of the upper body for independent living; thus, recovering upper body functions of their paralyzed side is not enough. Rehabilitation robots may be used to assist training without therapists. In this study, a small portable rehabilitation robot was developed for use at home, and a new training method was proposed. This robot consists on an omni wheel mechanism and a force sensor, and is capable of deciding the motion based on the force value. Voluntary movement of a hemiplegia patient is recovered by the rehabilitation robot and proposed training method. Thus, verification experiments were performed using participants with hemiplegia. The CCI (Co-Contraction Index) from after training were smaller than ones of before training, thus the movement skills of the participants improved with respect to controlling force direction and magnitude. Moreover, manual function test (MFT) scores increased as reflected by improvements in the motor function of the upper limb using the proposed training method.

  2. Polarizable empirical force field for acyclic polyalcohols based on the classical Drude oscillator.

    Science.gov (United States)

    He, Xibing; Lopes, Pedro E M; Mackerell, Alexander D

    2013-10-01

    A polarizable empirical force field for acyclic polyalcohols based on the classical Drude oscillator is presented. The model is optimized with an emphasis on the transferability of the developed parameters among molecules of different sizes in this series and on the condensed-phase properties validated against experimental data. The importance of the explicit treatment of electronic polarizability in empirical force fields is demonstrated in the cases of this series of molecules with vicinal hydroxyl groups that can form cooperative intra- and intermolecular hydrogen bonds. Compared to the CHARMM additive force field, improved treatment of the electrostatic interactions avoids overestimation of the gas-phase dipole moments resulting in significant improvement in the treatment of the conformational energies and leads to the correct balance of intra- and intermolecular hydrogen bonding of glycerol as evidenced by calculated heat of vaporization being in excellent agreement with experiment. Computed condensed phase data, including crystal lattice parameters and volumes and densities of aqueous solutions are in better agreement with experimental data as compared to the corresponding additive model. Such improvements are anticipated to significantly improve the treatment of polymers in general, including biological macromolecules.

  3. A Polymer-Based Capacitive Sensing Array for Normal and Shear Force Measurement

    Directory of Open Access Journals (Sweden)

    Ming-Yuan Cheng

    2010-11-01

    Full Text Available In this work, we present the development of a polymer-based capacitive sensing array. The proposed device is capable of measuring normal and shear forces, and can be easily realized by using micromachining techniques and flexible printed circuit board (FPCB technologies. The sensing array consists of a polydimethlysiloxane (PDMS structure and a FPCB. Each shear sensing element comprises four capacitive sensing cells arranged in a 2 × 2 array, and each capacitive sensing cell has two sensing electrodes and a common floating electrode. The sensing electrodes as well as the metal interconnect for signal scanning are implemented on the FPCB, while the floating electrodes are patterned on the PDMS structure. This design can effectively reduce the complexity of the capacitive structures, and thus makes the device highly manufacturable. The characteristics of the devices with different dimensions were measured and discussed. A scanning circuit was also designed and implemented. The measured maximum sensitivity is 1.67%/mN. The minimum resolvable force is 26 mN measured by the scanning circuit. The capacitance distributions induced by normal and shear forces were also successfully captured by the sensing array.

  4. Molecular recognition imaging using tuning fork-based transverse dynamic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hofer, Manuel; Adamsmaier, Stefan [University of Linz, Institute for Biophysics, Altenbergerstr. 69, 4040 Linz (Austria); Zanten, Thomas S. van [IBEC-Institute for Bioengineering of Catalonia and CIBER-Bbn, Baldiri i Reixac 15-21, Barcelona 08028 (Spain); Chtcheglova, Lilia A. [University of Linz, Institute for Biophysics, Altenbergerstr. 69, 4040 Linz (Austria); Manzo, Carlo [IBEC-Institute for Bioengineering of Catalonia and CIBER-Bbn, Baldiri i Reixac 15-21, Barcelona 08028 (Spain); Duman, Memed [University of Linz, Institute for Biophysics, Altenbergerstr. 69, 4040 Linz (Austria); Mayer, Barbara [Christian Doppler Laboratory for Nanoscopic Methods in Biophysics, Institute for Biophysics, University of Linz, Altenbergerstr. 69, 4040 Linz (Austria); Ebner, Andreas [University of Linz, Institute for Biophysics, Altenbergerstr. 69, 4040 Linz (Austria); Christian Doppler Laboratory for Nanoscopic Methods in Biophysics, Institute for Biophysics, University of Linz, Altenbergerstr. 69, 4040 Linz (Austria); Moertelmaier, Manuel; Kada, Gerald [Agilent Technologies Austria GmbH, Aubrunnerweg 11, 4040 Linz (Austria); Garcia-Parajo, Maria F. [IBEC-Institute for Bioengineering of Catalonia and CIBER-Bbn, Baldiri i Reixac 15-21, Barcelona 08028 (Spain); ICREA-Institucio Catalana de Recerca i Estudis Avancats, 08010 Barcelona (Spain); Hinterdorfer, Peter, E-mail: peter.hinterdorfer@jku.at [University of Linz, Institute for Biophysics, Altenbergerstr. 69, 4040 Linz (Austria); Christian Doppler Laboratory for Nanoscopic Methods in Biophysics, Institute for Biophysics, University of Linz, Altenbergerstr. 69, 4040 Linz (Austria); Kienberger, Ferry [Agilent Technologies Austria GmbH, Aubrunnerweg 11, 4040 Linz (Austria)

    2010-05-15

    We demonstrate simultaneous transverse dynamic force microscopy and molecular recognition imaging using tuning forks as piezoelectric sensors. Tapered aluminum-coated glass fibers were chemically functionalized with biotin and anti-lysozyme molecules and attached to one of the prongs of a 32 kHz tuning fork. The lateral oscillation amplitude of the tuning fork was used as feedback signal for topographical imaging of avidin aggregates and lysozyme molecules on mica substrate. The phase difference between the excitation and detection signals of the tuning fork provided molecular recognition between avidin/biotin or lysozyme/anti-lysozyme. Aggregates of avidin and lysozyme molecules appeared as features with heights of 1-4 nm in the topographic images, consistent with single molecule atomic force microscopy imaging. Recognition events between avidin/biotin or lysozyme/anti-lysozyme were detected in the phase image at high signal-to-noise ratio with phase shifts of 1-2{sup o}. Because tapered glass fibers and shear-force microscopy based on tuning forks are commonly used for near-field scanning optical microscopy (NSOM), these results open the door to the exciting possibility of combining optical, topographic and biochemical recognition at the nanometer scale in a single measurement and in liquid conditions.

  5. Bis(terpyridine)-based surface template structures on graphite: a force field and DFT study.

    Science.gov (United States)

    Künzel, Daniela; Markert, Thomas; Gross, Axel; Benoit, David M

    2009-10-21

    Host-guest networks formed by ordered organic layers are promising candidates for applications in molecular storage and quantum computing. We have studied 2-dimensionally ordered surface template structures of bis(terpyridine)-derived molecules (BTPs) on graphite using force field and DFT methods and compared the results to recent experimental observations. In order to determine the force field best suited for surface calculations, bond lengths and angles, torsional potentials, adsorption and stacking energies of smaller aromatic molecules were calculated with different force fields (Compass, UFF, Dreiding and CVFF). Density functional perturbation theory calculations were used to study the intermolecular interactions between 3,3'-BTP molecules. Structural properties, adsorption energies and rotational barriers of the 3,3'-BTP surface structure and its host-guest systems with phthalocyanine (PcH(2)) or excess 3,3'-BTP as guest molecules have been addressed. In addition, STM images of oligopyridine and phthalocyanine molecules were simulated based on periodic and local density functional theory calculations.

  6. Magnetic Field Equivalent Current Analysis-Based Radial Force Control for Bearingless Permanent Magnet Synchronous Motors

    Directory of Open Access Journals (Sweden)

    Huangqiu Zhu

    2015-05-01

    Full Text Available Bearingless permanent magnet synchronous motors (BPMSMs, with all advantages of permanent magnet motors (PMSMs and magnetic bearings, have become an important research direction in the bearingless motor field. To realize a stable suspension for the BPMSM, accurate decoupling control between the electromagnetic torque and radial suspension force is indispensable. In this paper, a concise and reliable analysis method based on a magnetic field equivalent current is presented. By this analysis method, the operation principle is analyzed theoretically, and the necessary conditions to produce a stable radial suspension force are confirmed. In addition, mathematical models of the torque and radial suspension force are established which is verified by the finite element analysis (FEA software ANSYS. Finally, an experimental prototype of a 2-4 poles surface-mounted BPMSM is tested with the customized control strategy. The simulation and experimental results have shown that the motor has good rotation and suspension performance, and validated the accuracy of the proposed analysis method and the feasibility of the control strategy.

  7. [The organizational bases for the building of a modern medical support system for the Armed Forces].

    Science.gov (United States)

    Chizh, I M

    1996-01-01

    In the article the problems concerning characteristic features of the local wars and armed conflicts, organization bases of construction of The Army and Fleet medical support modern system are discussed. The organization of personnel medical security is considered depending on the duration, intensity and spatial scope of military conflict, peculiarities of group (forces) application and ways of military actions conduction. The distribution of federal troops sanitary losses during the war in Chechenskaya Republic is shown depending on the type, localization and degree of injuries gravity as well as volume of the wounded and invalids evacuation by air transport and work of military medical institutions. The following principles of construction of the Armed Forces medical support system are formulated: The system must be in compliance with troops goals, structure, strategy and tactics, its specificity; development of medical security forms and methods, their historicism; interdependency, completeness and integrity of the system's elements; territorial aspects of its construction and management optimization. Considering character of the goals being laid on the Mobile Forces the paramount importance is attached to the level of readiness of medical service and its formations and units to act in crisis situations.

  8. Force-Field Based Quasi-Chemical Method for Rapid Evaluation of Binary Phase Diagrams.

    Science.gov (United States)

    Sweere, Augustinus J M; Fraaije, Johannes G E M

    2015-11-05

    We present the Pair Configurations to Molecular Activity Coefficients (PAC-MAC) method. The method is based on the pair sampling technique of Blanco (Fan, C. F.; Olafson, B. D.; Blanco, M.; Hsu, S. L. Application of Molecular Simulation to Derive Phase Diagrams of Binary Mixtures. Macromolecules 1992, 25, 3667-3676) with an extension that takes the packing of the molecules into account by a free energy model. The intermolecular energy is calculated using classical force fields. PAC-MAC is able to predict activity coefficients and corresponding vapor-liquid equilibrium diagrams at least 4 orders of magnitude faster than molecular simulations. The accuracy of the PAC-MAC method is tested by comparing the results with experimental data and with the results of the COSMO-SAC model (Lin, S.-T.; Sandler, S. I. A Priori Phase Equilibrium Prediction from a Segment Contribution Solvation Model. Ind. Eng. Chem. Res. 2002, 41, 899-913). PAC-MAC (using the OPLS-aa force field) is shown to be comparable in accuracy to COSMO-SAC, at the considerable advantage that PAC-MAC in principle does not require quantum calculation, provided proper force fields to be available.

  9. The strong prognostic value of KELIM, a model-based parameter from CA 125 kinetics in ovarian cancer

    DEFF Research Database (Denmark)

    You, Benoit; Colomban, Olivier; Heywood, Mark;

    2013-01-01

    Unexpected results were recently reported about the poor surrogacy of Gynecologic Cancer Intergroup (GCIG) defined CA-125 response in recurrent ovarian cancer (ROC) patients. Mathematical modeling may help describe CA-125 decline dynamically and discriminate prognostic kinetic parameters....

  10. The influence of physical and physiological cues on atomic force microscopy-based cell stiffness assessment.

    Directory of Open Access Journals (Sweden)

    Yu-Wei Chiou

    Full Text Available Atomic force microscopy provides a novel technique for differentiating the mechanical properties of various cell types. Cell elasticity is abundantly used to represent the structural strength of cells in different conditions. In this study, we are interested in whether physical or physiological cues affect cell elasticity in Atomic force microscopy (AFM-based assessments. The physical cues include the geometry of the AFM tips, the indenting force and the operating temperature of the AFM. All of these cues show a significant influence on the cell elasticity assessment. Sharp AFM tips create a two-fold increase in the value of the effective Young's modulus (E(eff relative to that of the blunt tips. Higher indenting force at the same loading rate generates higher estimated cell elasticity. Increasing the operation temperature of the AFM leads to decreases in the cell stiffness because the structure of actin filaments becomes disorganized. The physiological cues include the presence of fetal bovine serum or extracellular matrix-coated surfaces, the culture passage number, and the culture density. Both fetal bovine serum and the extracellular matrix are critical for cells to maintain the integrity of actin filaments and consequently exhibit higher elasticity. Unlike primary cells, mouse kidney progenitor cells can be passaged and maintain their morphology and elasticity for a very long period without a senescence phenotype. Finally, cell elasticity increases with increasing culture density only in MDCK epithelial cells. In summary, for researchers who use AFM to assess cell elasticity, our results provide basic and significant information about the suitable selection of physical and physiological cues.

  11. Building an open-source simulation platform of acoustic radiation force-based breast elastography.

    Science.gov (United States)

    Wang, Yu; Peng, Bo; Jiang, Jingfeng

    2017-03-07

    Ultrasound-based elastography including strain elastography, acoustic radiation force impulse (ARFI) imaging, point shear wave elastography and supersonic shear imaging (SSI) have been used to differentiate breast tumors among other clinical applications. The objective of this study is to extend a previously published virtual simulation platform built for ultrasound quasi-static breast elastography toward acoustic radiation force-based breast elastography. Consequently, the extended virtual breast elastography simulation platform can be used to validate image pixels with known underlying soft tissue properties (i.e. 'ground truth') in complex, heterogeneous media, enhancing confidence in elastographic image interpretations. The proposed virtual breast elastography system inherited four key components from the previously published virtual simulation platform: an ultrasound simulator (Field II), a mesh generator (Tetgen), a finite element solver (FEBio) and a visualization and data processing package (VTK). Using a simple message passing mechanism, functionalities have now been extended to acoustic radiation force-based elastography simulations. Examples involving three different numerical breast models with increasing complexity-one uniform model, one simple inclusion model and one virtual complex breast model derived from magnetic resonance imaging data, were used to demonstrate capabilities of this extended virtual platform. Overall, simulation results were compared with the published results. In the uniform model, the estimated shear wave speed (SWS) values were within 4% compared to the predetermined SWS values. In the simple inclusion and the complex breast models, SWS values of all hard inclusions in soft backgrounds were slightly underestimated, similar to what has been reported. The elastic contrast values and visual observation show that ARFI images have higher spatial resolution, while SSI images can provide higher inclusion-to-background contrast. In

  12. Building an open-source simulation platform of acoustic radiation force-based breast elastography

    Science.gov (United States)

    Wang, Yu; Peng, Bo; Jiang, Jingfeng

    2017-03-01

    Ultrasound-based elastography including strain elastography, acoustic radiation force impulse (ARFI) imaging, point shear wave elastography and supersonic shear imaging (SSI) have been used to differentiate breast tumors among other clinical applications. The objective of this study is to extend a previously published virtual simulation platform built for ultrasound quasi-static breast elastography toward acoustic radiation force-based breast elastography. Consequently, the extended virtual breast elastography simulation platform can be used to validate image pixels with known underlying soft tissue properties (i.e. ‘ground truth’) in complex, heterogeneous media, enhancing confidence in elastographic image interpretations. The proposed virtual breast elastography system inherited four key components from the previously published virtual simulation platform: an ultrasound simulator (Field II), a mesh generator (Tetgen), a finite element solver (FEBio) and a visualization and data processing package (VTK). Using a simple message passing mechanism, functionalities have now been extended to acoustic radiation force-based elastography simulations. Examples involving three different numerical breast models with increasing complexity—one uniform model, one simple inclusion model and one virtual complex breast model derived from magnetic resonance imaging data, were used to demonstrate capabilities of this extended virtual platform. Overall, simulation results were compared with the published results. In the uniform model, the estimated shear wave speed (SWS) values were within 4% compared to the predetermined SWS values. In the simple inclusion and the complex breast models, SWS values of all hard inclusions in soft backgrounds were slightly underestimated, similar to what has been reported. The elastic contrast values and visual observation show that ARFI images have higher spatial resolution, while SSI images can provide higher inclusion-to-background contrast

  13. Geology, hydrology, and water supply of Edwards Air Force Base, Kern County, California

    Science.gov (United States)

    Dutcher, Lee Carlton; Warts, G.F.

    1963-01-01

    Edwards Air Force Base occupies the northern part of Antelope Valley, California. As a result of large-scale and increasing agricultural pumping in the valley, the net draft has exceeded the perennial supply since about 1930 and was about 170,000 acre-feet in 1951--at least three times the estimated yield. As a result, there has been a continuing depletion of ground water stored in all the unconsolidated deposits, including the principal aquifers contained in the younger and older alluvium.

  14. Environmental Assessment: Construction of Consolidated Fuel Overhaul and Repair Facility at Tinker Air Force Base, Oklahoma

    Science.gov (United States)

    2007-10-01

    Historic Preservation Officer MH:bh Oklahoma Archeological Survey March 23, 2007 Trudi Logan Department of the Air Force 72 Air Base Wing (AFMC...Fox Larry Ci’l AETC CONS/LGCK; McKee John M Civ OC-ALC/FMA; King Thelma J Civ OC-ALC/FMC; Powell Paul A Civ 72 ABW/CECED; Powell Paul A Civ 72 ABW...L CIV OC-ALC/FMC Grimes Jim D Civ OC-ALC/FMC; Tomlinson Deborah L Civ OC-ALC/FMC; Fox Larry Civ AETC CONS/LGCK; McKee John M Civ OC-ALC/FMA; King

  15. Ground-based measurements of aerosol optical properties and radiative forcing in North China

    Institute of Scientific and Technical Information of China (English)

    Hongbin Chen; Xiangao Xia; Pucai Wang; Wenxing Zhang

    2007-01-01

    In order to gain an insight into the aerosol properties and their climatic effect over the continental source regions of China, it is of significance to carry out long-term ground-based measurements of aerosol optical properties and radiative forcing. A couple of temporary and permanent Aerosol Robotic Network (AERONET) sites and three comprehensive radiative sites were established in China as a result of international cooperation in recent years. Heavy aerosol loading and significant temporal and spatial variation over North China are revealed by the AERONET data.Aerosol-induced reductions in surface radiation budget are examined on the basis of collocated observations by sun photometers and pyranometers.

  16. Towards a unified realistic shell-model Hamiltonian with the monopole-based universal force

    CERN Document Server

    Kaneko, K; Sun, Y; Tazaki, S

    2013-01-01

    We propose a unified realistic shell-model Hamiltonian employing the pairing plus multipole Hamiltonian combined with the monopole interaction constructed starting from the monopole-based universal force by Otsuka it et al. (Phys. Rev. Lett. 104, 012501 (2010)). It is demonstrated that the proposed PMMU model can consistently describe a large amount of spectroscopic data as well as binding energies in the pf and pf5/2g9/2 shell spaces, and could serve as a practical shell model for even heavier mass regions.

  17. Modelling Inter-Particle Forces and Resulting Agglomerate Sizes in Cement-Based Materials

    DEFF Research Database (Denmark)

    Kjeldsen, Ane Mette; Geiker, Mette Rica

    2005-01-01

    The theory of inter-particle forces versus external shear in cement-based materials is reviewed. On this basis, calculations on maximum agglomerate size present after the combined action of superplasticizers and shear are carried out. Qualitative experimental results indicate that external shear...... affects the particle size distribution of Mg(OH)2 (used as model material) as well as silica, whereas the addition of superplasticizers affects only the smallest particles in cement and thus primarily acts as water reducers and not dispersers....

  18. Group 13, 1990 ASCAN Ellen Ochoa trains at Vance Air Force Base, Oklahoma

    Science.gov (United States)

    1990-01-01

    Group 13, 1990 Astronaut Candidate (ASCAN) Ellen Ochoa, wearing helmet and in full parachute equipment, waits while a training instructor adjusts her parachute harness prior to a parasail training exercise at Vance Air Force Base (AFB) in Enid, Oklahoma. When adjusted correctly, Ochoa will be pulled behind a moving vehicle to simulate a parachute jump from an airplane in an emergency situation. The parachute creates the backdrop for this photo. Ochoa, along with 22 other ASCANs, participated in this survival training course at Vance from 07-29-90 through 07-31-90.

  19. Group 13, 1990 ASCAN Ellen Ochoa parasails at Vance Air Force Base, Oklahoma

    Science.gov (United States)

    1990-01-01

    Group 13, 1990 Astronaut Candidate (ASCAN) Ellen Ochoa, wearing helmet and holding onto parachute harness, parasails during a survival training course exercise at Vance Air Force Base (AFB) in Enid, Oklahoma. In this phase of the course, the trainee, in full parachute equipment, is pulled behind a moving vehicle to simulate a parachute jump from an airplane in an emergency situation. Her parachute forms the backdrop for the photo. Ochoa, along with 22 other ASCANs, began a year's training and evaluation in July. This session was conducted from 07-29-90 through 07-31-90.

  20. Effect of tip shape on line edge roughness measurement based on atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Li Ning [Shanghai Second Polytechnic University, Shanghai 201209 (China); Wang Fei; Zhao Xuezeng [School of Mechanical and Electronic Engineering, Harbin Institute of Technology, Harbin 150001 (China)

    2010-12-15

    Atomic force microscopy (AFM) is an important tool in line edge roughness (LER) measurements, where accuracy for line edge identification is influenced by the shape of the tip. In this article, the effect of tip shape on LER measurement based on AFM is studied theoretically. The formulas for calculating the distance between the measured and actual line edge of the sample are presented. The effects of the three kinds of tips with different shapes are experimentally compared for validation. Suggestions on how to reduce measuring error caused by tip shape are also given.

  1. Socioeconomic Impact Analysis Study. Disposal and Reuse of Norton Air Force Base, California

    Science.gov (United States)

    1993-06-01

    The clinic at Norton offers outpatient-medical, I dental , and pharmaceutical services. On-base recreational facilities include a 2-8 Socioeconomic...units. 1990 dolor .. (d) Renter-occupied unite, 1990 dollars (by month). Sources: U.S. Bureau of the Census. 1982b, 1991. I increased markedly in all... dental outpatients in FY 1989, for an average of slightly more than 20,000 visits per month (U.S. Air Force, 1990b). The clinic’s staff conducted

  2. Atomic force microscopy based nanoindentation study of onion abaxial epidermis walls in aqueous environment

    Energy Technology Data Exchange (ETDEWEB)

    Xi, Xiaoning; Tittmann, Bernhard [Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Kim, Seong H. [Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2015-01-14

    An atomic force microscopy based nanoindentation method was employed to study how the structure of cellulose microfibril packing and matrix polymers affect elastic modulus of fully hydrated primary plant cell walls. The isolated, single-layered abaxial epidermis cell wall of an onion bulb was used as a test system since the cellulose microfibril packing in this cell wall is known to vary systematically from inside to outside scales and the most abundant matrix polymer, pectin, can easily be altered through simple chemical treatments such as ethylenediaminetetraacetic acid and calcium ions. Experimental results showed that the pectin network variation has significant impacts on the cell wall modulus, and not the cellulose microfibril packing.

  3. Measurement of Contractile Activity in Small Animal's Digestive Organ by Carbon Nanotube-Based Force Transducer

    Science.gov (United States)

    Hirata, Takamichi; Takeda, Naoki; Tsutsui, Chihiro; Koike, Kanako; Shimatani, Yuichi; Sakai, Takafumi; Akiya, Masahiro; Taguchi, Akira

    2011-03-01

    A carbon nanotube (CNT)-based force transducer designed to be embedded in the body of a live animal was fabricated and implanted into the stomach of a rat omit to measure contractile movement. The transducer comprised dispersed poly(ethylene glycol)-grafted multiwalled CNTs applied to a comb-like Au-electrode formed on a poly(dimethylsiloxane) sheet. The implanted rat was injected with acetylcholine to induce muscular contractions and changes in the resistance of the transducer were measured. Such changes arise owing to strain in the CNT network upon distortion. The measured resistance change was found to be proportional to the concentration of injected acetylcholine.

  4. Determination of Optimal Energy Efficient Separation Schemes based on Driving Forces

    DEFF Research Database (Denmark)

    Bek-Pedersen, Erik; Gani, Rafiqul; Levaux, O.

    2000-01-01

    A new integrated approach for synthesis, design and operation of separation schemes is presented. This integrated approach is based on driving forces that promote the desired separation for different separation techniques. A set of algorithms needed by the integrated approach for sequencing...... and design of distillation columns and for generating hybrid separation schemes are presented. The main feature of these algorithms is that they provide a 'visual' solution that also appears to be near optimal in terms of energy consumption. Several illustrative examples highlighting the application...

  5. Automated Solid-Phase Subcloning Based on Beads Brought into Proximity by Magnetic Force

    DEFF Research Database (Denmark)

    Hudson, Elton P.; Nikoshkov, Andrej; Uhlén, Mathias;

    2012-01-01

    and the gene are immobilized to separate paramagnetic beads and brought into proximity by magnetic force. Ligation events were directly evaluated using fluorescent-based microscopy and flow cytometry. The highest ligation efficiencies were obtained when gene- and vector-coated beads were brought into close...... contact by application of a magnet during the ligation step. An automated procedure was developed using a laboratory workstation to transfer genes into various expression vectors and more than 95% correct clones were obtained in a number of various applications. The method presented here is suitable...

  6. Operable Unit 1 remedial investigation report, Eielson Air Force Base, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Gilmore, T.J.; Fruland, R.M.; Liikala, T.L. [and others

    1994-06-01

    This remedial investigation report for operable Unit 1 (OU-1) at Eielson Air Force Base presents data, calculations, and conclusions as to the nature and extent of surface and subsurface contamination at the eight source areas that make up OU-1. The information is based on the 1993 field investigation result and previous investigations. This report is the first in a set of three for OU-1. The other reports are the baseline risk assessment and feasibility study. The information in these reports will lead to a Record of Decision that will guide and conclude the environmental restoration effort for OU-1 at Eielson Air Force Base. The primary contaminants of concern include fuels and fuel-related contaminants (diesel; benzene, toluene, ethylbenzene, and xylene; total petroleum hydrocarbon; polycyclic aromatic hydrocarbons), maintenance-related solvents and cleaners (volatile chlorinated hydrocarbons such as trichloroothylene), polychlorinated biphenyls, and dichlorodiphenyltrichloroethane (DDT). The origins of contaminants of concern include leaks from storage tanks, drums and piping, and spills. Ongoing operations and past sitewide practices also contribute to contaminants of concern at OU-1 source areas. These include spraying mixed oil and solvent wastes on unpaved roads and aerial spraying of DDT.

  7. Cell force mapping using a double-sided micropillar array based on the moiré fringe method

    Science.gov (United States)

    Zhang, F.; Anderson, S.; Zheng, X.; Roberts, E.; Qiu, Y.; Liao, R.; Zhang, X.

    2014-07-01

    The mapping of traction forces is crucial to understanding the means by which cells regulate their behavior and physiological function to adapt to and communicate with their local microenvironment. To this end, polymeric micropillar arrays have been used for measuring cell traction force. However, the small scale of the micropillar deflections induced by cell traction forces results in highly inefficient force analyses using conventional optical approaches; in many cases, cell forces may be below the limits of detection achieved using conventional microscopy. To address these limitations, the moiré phenomenon has been leveraged as a visualization tool for cell force mapping due to its inherent magnification effect and capacity for whole-field force measurements. This Letter reports an optomechanical cell force sensor, namely, a double-sided micropillar array (DMPA) made of poly(dimethylsiloxane), on which one side is employed to support cultured living cells while the opposing side serves as a reference pattern for generating moiré patterns. The distance between the two sides, which is a crucial parameter influencing moiré pattern contrast, is predetermined during fabrication using theoretical calculations based on the Talbot effect that aim to optimize contrast. Herein, double-sided micropillar arrays were validated by mapping mouse embryo fibroblast contraction forces and the resulting force maps compared to conventional microscopy image analyses as the reference standard. The DMPA-based approach precludes the requirement for aligning two independent periodic substrates, improves moiré contrast, and enables efficient moiré pattern generation. Furthermore, the double-sided structure readily allows for the integration of moiré-based cell force mapping into microfabricated cell culture environments or lab-on-a-chip devices.

  8. The study of CaSiO3 porous media heat and mass transfer based on the RMV%基于RMV的CaSiO3多孔介质热质传递机理研究

    Institute of Scientific and Technical Information of China (English)

    宋明启; 王志国; 宋永臣

    2015-01-01

    Based on representative macroscopic volume,this study established “three boxes”model of CaSiO 3 porous media,namely:black box model,gray box model and white box model.Deriving mathematical models to calculate thermal conductivity under the “three boxes”heat physical models.At the same time,the thermal conductivity which overheating H 2 O(g)in the state of 101.325 kPa and 400 K transfers CaSiO 3 representative macroscopic volume was calculated.What’s more,the temperature distribution of CaSiO 3 gray box heat trans-fer model was simulated when the porosity was 30% and 70%.The finding of this paper indicates that thermal conductivity decreases with increasing porosity,thermal conductivity increases with increasing pore channels distribution coefficient and tortuosity.The research results have important theory value and engineering applica-tion value for CaSiO 3 porous media and other inorganic materials porous media in heat and mass transferring.%基于粗宏观表征体元 RMV,建立了 CaSiO 3多孔介质“三箱”模型,即:黑箱模型、灰箱模型和白箱模型.推导了“三箱”传热物理模型下,导热系数计算的数学模型.数值计算了101.325 kPa、400 K 的过热水蒸气在 CaSiO 3粗宏观表征体元中传递时的导热系数.数值模拟了孔隙率为30%和70%的 CaSiO 3灰箱传热模型温度场分布.结果表明,导热系数随孔隙率增大而减小,导热系数随孔隙通道分布系数和迂曲度增大而增大.研究结果对 CaSiO 3多孔介质及其它功能材料多孔介质热质传递机理研究具有重要的理论价值和工程应用意义.

  9. Hydrogen production via sorption enhanced chemical looping reforming of glycerol using Ni-based oxygen carrier and Ca-based sorbent: Theoretical and experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Wenju Wang [Nanjing University of Science and Technology, Nanjing (China)

    2014-02-15

    The sorption enhanced chemical looping reforming of glycerol (SECLRG) was proposed. This process can produce high purity H{sub 2} without need for additional gas separation equipment. Thermodynamic analysis on the reformer of SECLRG was conducted based on the minimization of Gibbs free energy. The results show that the favorable operation conditions for reformer are pressures around 1-20 atm, temperatures around 800 K, oxygen excess number of 1, and sorbent excess number of 1. The thermal efficiency with steam addition is higher than that without steam addition. The SECLRG was also examined in a fixed bed reactor, with NiO/Al{sub 2}O{sub 3} and CaO particles as bed material and glycerol as fuel. Experimental results showed that the H{sub 2} molar fraction was higher with CaO than without it. Initially, high purity hydrogen (>95%) was obtained by SECLR of glycerol at 800 K and 1 atm.

  10. High-power picosecond 355 nm laser based on La₂CaB₁₀O₁₉ crystal.

    Science.gov (United States)

    Li, Kai; Zhang, Ling; Xu, Degang; Zhang, Guochun; Yu, Haijuan; Wang, Yuye; Shan, Faxian; Wang, Lirong; Yan, Chao; Wu, Yicheng; Lin, Xuechun; Yao, Jianquan

    2014-06-01

    Third harmonic generation experiments were performed on a type-I phase-matching La2CaB10O19 crystal cut at θ=49.4° and φ=0.0° with dimensions of 4.0  mm×4.0  mm×17.6  mm. A 1064 nm laser with a maximum average power of 35.2 W was employed as the fundamental light source, which has a pulse width of 10 picoseconds and a pulse repetition rate of 80 MHz. A type-I noncritical phase-matching LBO crystal was used to generate 532 nm lasers. By investigating a series of focusing lens combinations, a picosecond 355 nm laser of 5.3 W was obtained, which is the highest power of picosecond 355 nm laser based on a La2CaB10O19 crystal so far. The total conversion efficiency from 1064 to 355 nm was up to 15.1%.

  11. Climate responses to SATIRE and SIM-based spectral solar forcing in a 3D atmosphere-ocean coupled GCM

    Directory of Open Access Journals (Sweden)

    Wen Guoyong

    2017-01-01

    Full Text Available We apply two reconstructed spectral solar forcing scenarios, one SIM (Spectral Irradiance Monitor based, the other the SATIRE (Spectral And Total Irradiance REconstruction modeled, as inputs to the GISS (Goddard Institute for Space Studies GCMAM (Global Climate Middle Atmosphere Model to examine climate responses on decadal to centennial time scales, focusing on quantifying the difference of climate response between the two solar forcing scenarios. We run the GCMAM for about 400 years with present day trace gas and aerosol for the two solar forcing inputs. We find that the SIM-based solar forcing induces much larger long-term response and 11-year variation in global averaged stratospheric temperature and column ozone. We find significant decreasing trends of planetary albedo for both forcing scenarios in the 400-year model runs. However the mechanisms for the decrease are very different. For SATIRE solar forcing, the decreasing trend of planetary albedo is associated with changes in cloud cover. For SIM-based solar forcing, without significant change in cloud cover on centennial and longer time scales, the apparent decreasing trend of planetary albedo is mainly due to out-of-phase variation in shortwave radiative forcing proxy (downwelling flux for wavelength >330 nm and total solar irradiance (TSI. From the Maunder Minimum to present, global averaged annual mean surface air temperature has a response of ~0.1 °C to SATIRE solar forcing compared to ~0.04 °C to SIM-based solar forcing. For 11-year solar cycle, the global surface air temperature response has 3-year lagged response to either forcing scenario. The global surface air 11-year temperature response to SATIRE forcing is about 0.12 °C, similar to recent multi-model estimates, and comparable to the observational-based evidence. However, the global surface air temperature response to 11-year SIM-based solar forcing is insignificant and inconsistent with observation-based evidence.

  12. American Recovery and Reinvestment Act (ARRA) Federal Energy Management Program Technical Assistance Project 224 Altus Air Force Base Solar Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Russo, Bryan J.

    2010-09-30

    The principal goal of this project was to evaluate altus Air Force Base for building integrated silicon or thin film module photovoltaic opportunities. This report documents PNNL's efforts and documents study conclusions.

  13. Ca- and Sc-based ternary AlB2-like crystals: a first-principles study

    Science.gov (United States)

    Tsetseris, Leonidas

    2017-02-01

    The aluminum diboride (AlB2) crystal structure comprises intercalated metal atoms between honeycomb sheets. In addition to metal diborides, which represent the most common family of AlB2-like structures, many more materials are known to crystallize in this geometry. Here we use first-principles calculations to probe the structural and electronic properties of several such systems. Specifically, we investigate the stability of various polymorphs of CaAuAs, CaAuP, CaCuP, ScAuGe, ScAuSi, Ca2AgSi3 and Ca2AuGe3 and find lattice parameters in excellent agreement with available experimental data. The analysis of densities of states and band structure diagrams show that all materials are metallic. However, the details of band dispersion vary significantly, from typical metals such as CaAuP, to almost semi-metallic behaviour in CaCuP.

  14. Multi-species coral Sr/Ca-based sea-surface temperature reconstruction using Orbicella faveolata and Siderastrea siderea from the Florida Straits

    Science.gov (United States)

    Flannery, Jennifer A.; Richey, Julie N.; Thirumalai, Kaustubh; Poore, Richard Z.; DeLong, Kristine L.

    2017-01-01

    We present new, monthly-resolved Sr/Ca-based sea-surface temperature (SST) records from two species of massive coral, Orbicella faveolata and Siderastrea siderea, from the Dry Tortugas National Park, FL, USA (DTNP). We combine these new records with published data from three additional S. siderea coral colonies to generate a 278-year long multi-species stacked Sr/Ca-SST record from DTNP. The composite record of mean annual Sr/Ca-SST at DTNP shows pronounced decadal-scale variability with a range of 1 to 2°C. Notable cool intervals in the Sr/Ca-derived SST lasting about a decade centered at ~1845, ~1935, and ~1965 are associated with reduced summer Sr/Ca-SST (monthly maxima < 29°C), and imply a reduction in the spatial extent of the Atlantic Warm Pool (AWP). There is significant coherence between the composite DTNP Sr/Ca-SST record and the Atlantic Multidecadal Oscillation (AMO) index, with the AMO lagging Sr/Ca-SST at DTNP by 9 years. Low frequency variability in the Gulf Stream surface transport, which originates near DTNP, may provide a link for the lagged relationship between multidecadal variability at DTNP and the AMO.

  15. Effect of sintering temperature on the thermal properties of diopside-based glass-ceramics of varying CaO/MgO ratio.

    Science.gov (United States)

    Jang, Seokju; Kang, Seunggu

    2013-08-01

    The thermal properties of diopside (CaMgSi2O6)-based glass-ceramics of varying CaO/MgO ratio were investigated as a function of sintering temperature. The crystallization behavior of the glass was studied by a non-isothermal method using a differential thermal analysis (DTA) with various heating rates. Diopside, as a main crystalline phase, and cordierite, as a minor phase, were formed in the glass-ceramics with an - 0.67-2.23 CaO/MgO ratio. The X-ray diffraction peak for diopside in the glass-ceramic becomes higher with an increase of the CaO/MgO ratio. The crystallization volume fraction with sintering temperature was calculated showing that both the initiation temperature for crystallization and a temperature range of crystallization increased with an increased heating rate. The microstructure of all glass-ceramics had a lump area composed of several tens-of-nanometer particles and a matrix composed of rows of particles, and the matrix area decreased with a decreasing CaO/MgO ratio. The thermal conductivity of glass-ceramics of CaO/MgO = 2.23 was 44% higher than that of CaO/MgO = 0.67 owing to the higher crystallinity and less voids in a microstructure. All glass-ceramics fabricated in this study were sintered at below 955 degrees C, which makes them applicable to the LTCC process for light-emitting diode packaging.

  16. The B/Ca proxy for past seawater carbonate chemistry reconstructions-laser ablation based calibrations for C. mundulus, C. wuellerstorfi and its morphotype C. cf. wuellerstorfi

    Science.gov (United States)

    Kersten, F.; Tiedemann, R.; Fietzke, J.; Frische, M.

    2013-08-01

    B/Ca ratios in Cibicides mundulus and Cibicides wuellerstorfi have been shown to correlate with the degree of calcite saturation in seawater (Δ[CO32-]). In the South Pacific, a region of high importance in the global carbon cycle, these species are not continuously present in down-core records. Small numbers of epibenthic foraminifera in samples present an additional challenge, which can be overcome by using laser ablation-inductively coupled-mass spectrometry (LA-ICP-MS). We present a laser ablation based core-top calibration for Cibicides cf. wuellerstorfi, a C. wuellerstorfi morphotype that is abundant in the South Pacific and extend the existing global core top calibration for C. mundulus and C. wuellerstorfi to this region. B/Ca in C. cf. wuellerstorfi are linearly correlated with Δ[CO32-] and possibly display a higher sensitivity to calcite saturation changes than C. wuellerstorfi. Trace element profiles through C. wuellerstorfi and C. mundulus reveal an intra-shell B/Ca variation of ±36% around the mean shell value. Mg/Ca and B/Ca display opposite trends along the shell. Both phenomena likely result from ontogenetic effects. Intra-shell variability equals intra-sample variability, mean sample B/Ca values can thus be reliably calculated from averaged spot results of single specimen. In the global B/Ca-Δ[CO32-] range, we observe an inverse relationship between water mass age and Δ[CO32-].

  17. Adaptive method for real-time gait phase detection based on ground contact forces.

    Science.gov (United States)

    Yu, Lie; Zheng, Jianbin; Wang, Yang; Song, Zhengge; Zhan, Enqi

    2015-01-01

    A novel method is presented to detect real-time gait phases based on ground contact forces (GCFs) measured by force sensitive resistors (FSRs). The traditional threshold method (TM) sets a threshold to divide the GCFs into on-ground and off-ground statuses. However, TM is neither an adaptive nor real-time method. The threshold setting is based on body weight or the maximum and minimum GCFs in the gait cycles, resulting in different thresholds needed for different walking conditions. Additionally, the maximum and minimum GCFs are only obtainable after data processing. Therefore, this paper proposes a proportion method (PM) that calculates the sums and proportions of GCFs wherein the GCFs are obtained from FSRs. A gait analysis is then implemented by the proposed gait phase detection algorithm (GPDA). Finally, the PM reliability is determined by comparing the detection results between PM and TM. Experimental results demonstrate that the proposed PM is highly reliable in all walking conditions. In addition, PM could be utilized to analyze gait phases in real time. Finally, PM exhibits strong adaptability to different walking conditions.

  18. Modelling of Ion Transport in Solids with a General Bond Valence Based Force-Field

    Directory of Open Access Journals (Sweden)

    S. Adams

    2010-12-01

    Full Text Available Empirical bond length - bond valence relations provide insight into the link between structure of and ion transport in solid electrolytes. Building on our earlier systematic adjustment of bond valence (BV parameters to the bond softness, here we discuss how the squared BV mismatch can be linked to the absolute energy scale and used as a general Morse-type interaction potential for analyzing low-energy pathways in ion conducting solid or mixed conductors either by an energy landscape approach or by molecular dynamics (MD simulations. For a wide range of Lithium oxides we could thus model ion transport revealing significant differences to an earlier geometric approach. Our novel BV-based force-field has also been applied to investigate a range of mixed conductors, focusing on cathode materials for lithium ion battery (LIB applications to promote a systematic design of LIB cathodes that combine high energy density with high power density. To demonstrate the versatility of the new BV-based force-field it is applied in exploring various strategies to enhance the power performance of safe low cost LIB materials (LiFePO4, LiVPO4F, LiFeSO4F, etc..

  19. Combat Support Forces (1C6C) Naval Surface Forces Requirements-based Budget Determination for Assault Craft Unit ONE

    Science.gov (United States)

    2009-06-01

    period of time. It is an instrument of planning, performance measurement, decision-making, and management control , as well as a statement of priorities...Dimmerling, 1997). In 1995, Fleming wrote of the importance of budgeting. She states that “budgeting is one of the important planning and control ...Landing Craft Air Cushioned (LCAC) hovercrafts out of its base at Marine Corps Base Camp Pendleton located in North San Diego County, California

  20. Exponential Brute-Force Complexity of A Permutation Based Stream Cipher

    Directory of Open Access Journals (Sweden)

    Mohammed Omari

    2013-01-01

    Full Text Available This paper introduces a permutation generation mechanism based on a shared secret key. The generated permutation vectors are used as encryption keys in a stream ciphering cryptosystem. We investigated various types of attacks on the known stream cipher RC4 and patched most of its loopholes, especially biased-byte and state-related attacks. Unique to our approach, we prove mathematically that the complexity of brute-forcing such a system is (2n, where n is the key size in bytes. This paper also presents a complete security model using permutation-based encryption, in order to handle privacy. In addition, our approach achieved higher performance than that of existing peer techniques, while maintaining solid security. Experimental results show that our system is much faster than the existing security mechanisms, such as AES and DES.

  1. Eielson Air Force Base operable unit 2 and other areas record of decision

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, R.E.; Smith, R.M.

    1994-10-01

    This decision document presents the selected remedial actions and no action decisions for Operable Unit 2 (OU2) at Eielson Air Force Base (AFB), Alaska, chosen in accordance with state and federal regulations. This document also presents the decision that no further action is required for 21 other source areas at Eielson AFB. This decision is based on the administrative record file for this site. OU2 addresses sites contaminated by leaks and spills of fuels. Soils contaminated with petroleum products occur at or near the source of contamination. Contaminated subsurface soil and groundwater occur in plumes on the top of a shallow groundwater table that fluctuates seasonally. These sites pose a risk to human health and the environment because of ingestion, inhalation, and dermal contact with contaminated groundwater. The purpose of this response is to prevent current or future exposure to the contaminated groundwater, to reduce further contaminant migration into the groundwater, and to remediate groundwater.

  2. Environmental Assessment for Construction of Base Training Area, Schriever Air Force Base, Colorado

    Science.gov (United States)

    2010-12-01

    bed-down, biological/chemical warfare training, and bivouac training. In order to meet air quality standards when smoke grenades/obscurants are used...users of the Base Training Area would be active duty military assigned to SAFB. To ensure that no smoke or dust leave the SAFB boundary, any smoke ...receipt of the above referenced Environmental Assesment and is familiar with the site. Based on the location and type of action being proposed the

  3. Electromagnetic behavior of radar absorbing materials based on Ca hexaferrite modified with Co-Ti ions and doped with La

    Directory of Open Access Journals (Sweden)

    Valdirene Aparecida da Silva

    2009-06-01

    Full Text Available Radar Absorbing Materials (RAM are compounds that absorb incidental electromagnetic radiation in tuned frequencies and dissipate it as heat. Its preparation involves the adequate processing of polymeric matrices filled with compounds that act as radar absorbing centers in the microwave range. This work shows the electromagnetic evaluation of RAM based on CoTi and La doped Ca hexaferrite. Vibrating Sample Magnetization analyses show that ion substitution promoted low values for the parameters of saturation magnetization (123.65 Am2/kg and coercive field (0.07 T indicating ferrite softening. RAM samples obtained using different hexaferrite concentrations (40-80 per cent, w/w show variations in complex permeability and permittivity parameters and also in the performance of incidental radiation attenuation. Microwave attenuation values between 40 and 98 per cent were obtained.

  4. Spatial Dynamic Models for Inclusive Cities: a Brief Concept of Cellular Automata (CA and Agent-Based Model (ABM

    Directory of Open Access Journals (Sweden)

    Agung Wahyudi

    2015-04-01

    Full Text Available Abstrak.Kawasan perkotaan terutama di negara-negara berkembang menunjukkan laju pertumbuhan fisik yang tinggi. Telah banyak model yang mencoba merekonstruksi pertumbuhan perkotaan ini dengan menggunakan data demografi dan data sosial. Permodelan ini adalah salah satu yang lazim digunakan para praktisi perencana karena ketersediaan data dan waktu proses yang relatif lebih singkat. Sayangnya, model ini bersifat statis yaitu hanya menangkap karakteristik dan bentuk kota pada satu satuan waktu. Model ini tidak akan berubah saat variabel waktu berubah. Kebanyakan model ini bertujuan untuk memperkuat atau memperjelas suatu teori perencanaan perkotaan. Model statis ini juga memanfaatkan batas-batas administrasi dan tidak memungkinkan untuk melakukan permodelan diluar bentuk administrasi sebuah kota. Dengan permasalahan perkotaan yang semakin rumit yang menuntut pengambil keputusan membuat kebijakan tepat, diperlukan suatu metode permodelan pertumbuhan perkotaan yang dinamis yang dapat memberikan informasi yang lebih lengkap kepada pengambil kebijakan terkait struktur dan bentuk perkotaan, serta beroperasi pada skala yang lebih detail. Kemudian model perkotaan ini juga perlu mewakili perilaku para aktor pembangunan perkotaan. Salah satu konsep yang berkembang sejak tiga dasawarsa lalu adalah cellular automata (CA dan agent-based urban model (ABM. Dalam konteks penelitian perkotaan di Indonesia, sayangnya konsep-konsep ini belum banyak tersedia pada jurnal-jurnal perkotaan dan terlebih lagi belum banyak kontribusi pada konsep-konsep permodelan dan mekanisme pada proses perubahan guna/tutupan lahan. Artikel ini bertujuan untuk memperkenalkan teori dasar CA dan adaptasi dari sistem tersebut untuk keperluan aplikasi di bidang spasial perkotaan. Kami juga akan menjelaskan konsep ABM sebagai komponen dari model yang memiliki kemampuan mewakili perilaku para pelaku pembangunan. Beberapa contoh aplikasi dan kemungkinan perkembangan model dinamis untuk kota

  5. Elaboración de Bebida Refrescante con Base en Miel de Caña

    Directory of Open Access Journals (Sweden)

    Sepúlveda Valencia José Uriel

    1998-12-01

    Full Text Available Con el fin de determinar las características de la bebida refrescante elaborada con miel de caña, naranja agria, limón mandarino y ácido cítrico más ácido ascórbico, se elaboraron en la Planta de Leches de la Universidad Nacional de Colombia. Sede Medellín, bebidas a las cuales se les efectuaron análisis físico químicos, microbiológicos y organolépticos en los días uno y quince después de preparados. Los análisis se determinaron así: los físico químicos: los sólidos solubles se expresaron en °Brix determinados por el método de refractometría, la densidad por el método del picnómetro, la acidez por el método de titulación con hidróxido de sodio (NaOH 0,1 N. el pH mediante potenciometría y la viscosidad por el método de Ostwald. Los microbiológicos: coliformes totales y fecales por el método de tubos con caldo lactosado verde bilis brillante, los mohos y levaduras por recuento en placa con agar potato y el recuento total de mesoaerobios por el método de placas con agar nutritivo. Se realizaron tres tratamientos (naranja agria, limón mandarino y ácido cítrico más ácido ascórbico y cada tratamiento se replicó cuatro (4 veces. En los análisis físico químicos entre los tratamientos se encontraron diferencias significativas en las variables pH, viscosidad y densidad con respecto al sabor en el tiempo. No se encontraron diferencias significativas para °Brix y acidez titulable. En el análisis microbiológico para la variable mohos hubo diferencia significativa en el tiempo de almacenamiento, más no en el sabor, las otras variables recuento total de mesoaerobios y número más probable de coliformes totales y fecales no presentaron diferencias significativas. En el análisis organoléptico se encontraron diferencias significativas entre los sabores y el tiempo. Los puntajes obtenidos indicaron, en general una buena aceptación de la bebida refrescante por parte de los 18 jueces, siendo superior el

  6. The Polarizable Atomic Multipole-based AMOEBA Force Field for Proteins.

    Science.gov (United States)

    Shi, Yue; Xia, Zhen; Zhang, Jiajing; Best, Robert; Wu, Chuanjie; Ponder, Jay W; Ren, Pengyu

    2013-01-01

    Development of the AMOEBA (Atomic Multipole Optimized Energetics for Biomolecular Simulation) force field for proteins is presented. The current version (AMOEBA-2013) utilizes permanent electrostatic multipole moments through the quadrupole at each atom, and explicitly treats polarization effects in various chemical and physical environments. The atomic multipole electrostatic parameters for each amino acid residue type are derived from high-level gas phase quantum mechanical calculations via a consistent and extensible protocol. Molecular polarizability is modeled via a Thole-style damped interactive induction model based upon distributed atomic polarizabilities. Inter- and intramolecular polarization is treated in a consistent fashion via the Thole model. The intramolecular polarization model ensures transferability of electrostatic parameters among different conformations, as demonstrated by the agreement between QM and AMOEBA electrostatic potentials, and dipole moments of dipeptides. The backbone and side chain torsional parameters were determined by comparing to gas-phase QM (RI-TRIM MP2/CBS) conformational energies of dipeptides and to statistical distributions from the Protein Data Bank. Molecular dynamics simulations are reported for short peptides in explicit water to examine their conformational properties in solution. Overall the calculated conformational free energies and J-coupling constants are consistent with PDB statistics and experimental NMR results, respectively. In addition, the experimental crystal structures of a number of proteins are well maintained during molecular dynamics (MD) simulation. While further calculations are necessary to fully validate the force field, initial results suggest the AMOEBA polarizable multipole force field is able to describe the structure and energetics of peptides and proteins, in both gas-phase and solution environments.

  7. Influence of CaZrO3 on dielectric properties and microstructures of BaTiO3-based X8R ceramics

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The influences of CaZrO3 on the dielectric properties and microstructures of BaTiO3 (BT)-based ceramics have been investigated. The experiment results showed that the dielectric constant at room temperature increased with the addition of CaZrO3 in the range of 0―3.0 mol%, which could be explained by the growth of BT grains. XRD analysis revealed that the tetragonality declined as CaZrO3 concentration in-creased. XRD patterns of BT ceramics with different amounts of CaZrO3 doping were analyzed by a recently developed procedure-materials analysis using diffrac-tion (MAUD), which was based on the Rietveld method combined with Fourier analysis. The results depicted that the high temperature peak of tempera-ture-capacitance characteristics (TCC) was largely dependent on the micro-strain of samples. Furthermore, more CaZrO3 doping resulted in lower porosity and higher density. It was revealed that proper usage of CaZrO3 could improve the di-electric properties significantly, which was benefit to develop X8R multi-layer ce-ramic capacitors.

  8. Influence of CaZrO3 on dielectric properties and microstructures of BaTiO3-based X8R ceramics

    Institute of Scientific and Technical Information of China (English)

    TANG Bin; ZHANG ShuRen; YUAN Ying; ZHOU XiaoHua; LIANG YiShuai

    2008-01-01

    The influences of CaZrO3 on the dielectric properties and microstructures of BaTiO3 (BT)-based ceramics have been investigated. The experiment results showed that the dielectric constant at room temperature increased with the addition of CaZrO3 in the range of 0-3.0 mol%, which could be explained by the growth of BT grains. XRD analysis revealed that the tetragonality declined as CaZrO3 concentration in- creased. XRD patterns of BT ceramics with different amounts of CaZrO3 doping were analyzed by a recently developed procedure-materials analysis using diffrac- tion (MAUD), which was based on the Rietveld method combined with Fourier analysis. The results depicted that the high temperature peak of tempera- ture-capacitance characteristics (TCC) was largely dependent on the micro-strain of samples. Furthermore, more CaZrO3 doping resulted in lower porosity and higher density. It was revealed that proper usage of CaZrO3 could improve the di- electric properties significantly, which was benefit to develop X8R multi-layer ce- ramic capacitors.

  9. The study on the atomic force microscopy base nanoscale electrical discharge machining.

    Science.gov (United States)

    Huang, Jen-Ching; Chen, Chung-Ming

    2012-01-01

    This study proposes an innovative atomic force microscopy (AFM) based nanoscale electrical discharge machining (AFM-based nanoEDM) system which combines an AFM with a self-produced metallic probe and a high-voltage generator to create an atmospheric environment AFM-based nanoEDM system and a deionized water (DI water) environment AFM-based nanoEDM system. This study combines wire-cut processing and electrochemical tip sharpening techniques on a 40-µm thick stainless steel sheet to produce a high conductive AFM probes, the production can withstand high voltage and large current. The tip radius of these probes is approximately 40 nm. A probe test was executed on the AFM using probes to obtain nanoscales morphology of Si wafer surface. The silicon wafer was as a specimen to carry out AFM-base nanoEDM process in atmospheric and DI water environments by AFM-based nanoEDM system. After experiments, the results show that the atmospheric and DI water environment AFM-based nanoEDM systems operate smoothly. From experimental results, it can be found that the electric discharge depth of the silicon wafer at atmospheric environments is a mere 14.54 nm. In a DI water environment, the depth of electric discharge of the silicon wafer can reach 25.4 nm. This indicates that the EDM ability of DI water environment AFM-based nanoEDM system is higher than that of atmospheric environment AFM-based nanoEDM system. After multiple nanoEDM process, the tips become blunt. After applying electrochemical tip sharpening techniques, the tip radius can return to approximately 40 nm. Therefore, AFM probes produced in this study can be reused.

  10. Potential overflow of Mojave Creek near disposal site, Edwards Air Force Base, California

    Science.gov (United States)

    Dinehart, Randy L.; Harmon, Jerry G.

    1998-01-01

    Sedimentological evidence in Mojave Creek near Edwards, California, indicates that the largest discharge in the last hundred years near the disposal site of the Main Base Landfill at Edwards Air Force Base was a few hundred cubic feet per second. The distal ends of two alluvial fans on the Mojave Creek floodplain near the Main Base Landfill have not been eroded substantially since sediment supply was cut off by a railroad grade completed in 1884. Previous estimates of flood discharges were 4,000 cubic feet per second and larger in this reach; the estimates were calculated by regression equations derived from regional characteristics. However, a 100-year rainfall in 1983 failed to produce erosion in Mojave Creek commensurate with discharges of greater than about 100 cubic feet per second. To test the potential for the creek to overflow and reach the disposal site, a hypothetical discharge was used to determine the depth of flooding at local cross sections. Although the access road from Mojave Boulevard to the Main Base Landfill may be inundated during a flood, the artificial grade at the disposal site would not be reached at a discharge of 2,000 cubic feet per second, which is an order of magnitude greater than the apparent flood discharges that occurred during the past hundred years in Mojave Creek near the present Main Base Landfill.

  11. Point Defects in Carbon Nanotubes: ab initio and Force-Fields Based Simulations

    Science.gov (United States)

    Kroes, Jaap; Pietrucci, Fabio; Curioni, Alessandro; Andreoni, Wanda

    2014-03-01

    We present an extended investigation of point defects in carbon nanotubes (CNTs) and their effects on mechanical and electronic properties. This study is based on large-scale calculations using DFT with exchange and correlation functionals of the GGA - including empirical corrections for van-der-Waals interactions - and of the hybrid type. Additional simulations using classical interatomic potentials allow us to obtain a critical comparison between the outcome of DFT and force-fields. The CNT models adopted have a range of sizes and chiralities. In particular, (i) our simulations of oxygen chemisorption revealed a tendency to clustering and the existence of kinetic traps (epoxides), which explain STS data; (ii) the extension to oxygen isovalent species on CNTs and other graphitic surfaces has suggested a simple predictive model for the chemisorption pattern. Moreover, (iii) our analysis shows an intrinsic difficulty of available force fields to account for the energetics of vacancies and adsorption site preferences. Additional results aiming at characterizing the interaction of nitrogen oxides (NOx) with the CNT surface will also be presented. Work supported by SNSF Nano-Tera.ch and CSCS.

  12. Robins Air Force Base integrated resource assessment. Volume 3, Resource assessment

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, G.P.; Keller, J.M.; Stucky, D.J.; Wahlstrom, R.R.; Larson, L.L.

    1993-10-01

    The US Air Force Materiel Command (AFMC) has tasked the US Department of Energy (DOE) Federal Energy Management Program (FEMP), supported by the Pacific Northwest Laboratory (PNL), to identify, evaluate, and assist in acquiring all cost-effective energy projects at Robins Air Force Base (AFB). This is part of a model program that PNL is designing to support energy-use decisions in the federal sector. This report provides the results of the fossil fuel and electric energy resource opportunity (ERO) assessments performed by PNL at the AFMC Robins AFB facility located approximately 15 miles south of Macon, Georgia. It is a companion report to Volume 1, Executive Summary, and Volume 2, Baseline Detail. The results of the analyses of EROs are presented in 13 common energy end-use categories (e.g., boilers and furnaces, service hot water, and building lighting). A narrative-description of each ERO is provided, including information on the installed cost, energy and dollar savings; impacts on operation and maintenance (O&M); and, when applicable, a discussion of energy supply and demand, energy security, and environmental issues. A description of the evaluation methodologies and technical and cost assumptions is also provided for each ERO. Summary tables present the cost-effectiveness of energy end-use equipment before and after the implementation of each ERO and present the results of the life-cycle cost (LCC) analysis indicating the net present value (NPV) and savings to investment ratio (SIR) of each ERO.

  13. The force analysis for superparamagnetic nanoparticles-based gene delivery in an oscillating magnetic field

    Science.gov (United States)

    Sun, Jiajia; Shi, Zongqian; Jia, Shenli; Zhang, Pengbo

    2017-04-01

    Due to the peculiar magnetic properties and the ability to function in cell-level biological interaction, superparamagnetic nanoparticles (SMNP) have been being the attractive carrier for gene delivery. The superparamagnetic nanoparticles with surface-bound gene vector can be attracted to the surface of cells by the Kelvin force provided by external magnetic field. In this article, the influence of the oscillating magnetic field on the characteristics of magnetofection is studied in terms of the magnetophoretic velocity. The magnetic field of a cylindrical permanent magnet is calculated by equivalent current source (ECS) method, and the Kelvin force is derived by using the effective moment method. The results show that the static magnetic field accelerates the sedimentation of the particles, and drives the particles inward towards the axis of the magnet. Based on the investigation of the magnetophoretic velocity of the particle under horizontally oscillating magnetic field, an oscillating velocity within the amplitude of the magnet oscillation is observed. Furthermore, simulation results indicate that the oscillating amplitude plays an important role in regulating the active region, where the particles may present oscillating motion. The analysis of the magnetophoretic velocity gives us an insight into the physical mechanism of the magnetofection. It's also helpful to the optimal design of the magnetofection system.

  14. Patrick Air Force Base integrated resource assessment. Volume 3, Resource assessment

    Energy Technology Data Exchange (ETDEWEB)

    Sandusky, W.F.; Parker, S.A.; King, D.A.; Wahlstrom, R.R.; Elliott, D.B.; Shankle, S.A.

    1993-12-01

    The US Air Force has tasked the Pacific Northwest Laboratory (PNL) in support of the US Department of Energy Federal Energy Management Program to identify, evaluate, and assist in acquiring all cost effective energy projects at Patrick Air Force Base (AFB). This is part of a model program that PNL is designing to support energy-use decisions in the federal sector. This report provides the results of the fossil fuel and electric energy resource opportunity (ERO) assessments performed by PNL at Patrick AFB which is located south of Cocoa Beach, Florida. It is a companion report to Volume 1, Executive Summary, and Volume.2, Baseline Detail. The results of the analyses of EROs are presented in 11 common energy end-use categories. A narrative description of each ERO is provided, including information on the installed cost, energy and dollar savings, impacts on operations and maintenance, and, when applicable, a discussion of energy supply and demand, energy security, and environmental issues. A description of the evaluation methodologies and technical and cost assumptions is also provided for each ERO. Summary tables present the cost-effectiveness of energy end-use equipment before and after the implementation of each ERO and present the results of the life-cycle cost analysis indicating the net present value and value index of each ERO.

  15. Web-based evaluation of experts' opinions on impacted maxillary canines forced eruption using CBCT

    Directory of Open Access Journals (Sweden)

    Amirfarhang Miresmaeili

    2015-04-01

    Full Text Available AIM: This study aims at examining the difficulty in performing forced eruption of impacted maxillary canines, using CBCT information and according to experienced orthodontist's opinion. The second aim was to find the most important factors related to this decision. METHODS: Based on a careful literature review on impacted maxillary canines, ten main factors were selected to assess difficulties associated with impacted teeth. Thirty six consecutive patients with 50 impacted maxillary canines were examined and variables were measured for each impacted tooth using Dolphin 3D software. Ten orthodontists assessed the radiographs of teeth and provided their opinion on the difficulty in bringing impacted teeth into occlusion named subjective degree of difficulty (SDD. The correlation established between mean SDD of each tooth and measured variables were analyzed by means of linear regression. RESULTS: Mean SDD was 6.45 ± 1.22 for all 50 teeth. Linear regression showed a high coefficient of correlation between mean SDD and age, dilacerations, vertical height, angulation and horizontal overlap (P < 0.05. CONCLUSION: To predict the difficulty of impacted maxillary canines forced eruption, according to the opinion of experienced orthodontists, the factors age, dilaceration, angulation, overlap and vertical distance from the occlusal plane are the most important variables.

  16. A Two-Dimensional Deflection Sensor Based on Force Sensing Resistors

    Directory of Open Access Journals (Sweden)

    Chuangqiang Guo

    2017-01-01

    Full Text Available A flexible deflection sensor for elastic shaft with the capability of measuring the amplitude and direction of bending is introduced in this paper. A thin force sensing resistors (FSR film is taken as its basic material, which is sandwiched by an elastomer layer and a printed circuit board (PCB with detecting electrode grids. Two fix rings are used to fix the three thin components perpendicularly to the longitudinal direction of the flexible shaft. When the shaft bends under forces, the fix rings will generate a normal pressure on FSR, which will cause the change of the resistance. Therefore, the amplitude of bending can be got based on the value of resistance. The electrode grid on the PCB is divided into four detection areas used to estimate the distribution of normal pressure on the FSR; thus the bending direction of shaft can also be obtained. Test results of a prototype (140 mm in length show that the amplitude of deflection can reach 30 mm and the sensitivities of sensor are 40.37, 32.8, 37.77, and 39.47 mV/mm in the four directions, respectively. The proposed flexible deflection sensor can be applied in continuum robots or other applications, which require rapid measurement of bending amplitude and direction.

  17. Quality of handwriting: Intervention based on the variation of finger force production

    Directory of Open Access Journals (Sweden)

    Adriano Percival Calvo

    2014-09-01

    Full Text Available Difficulties in the production of proficient handwriting can be detected early in childhood. From the control point of view, non-proficient handwriting can be explained by the difficulty in adequately activating motor synergies that give support to this motor skill. Therefore, imposing different demand on the control to the motor synergies of the fingers can generate improvement in the quality of handwriting. The goal of the present study was to verify the effects of an intervention program for children with handwriting difficulties, composed of manipulative and pre-calligraphic activities that stimulate finger motor synergies through different force production demands. Thirty-four children between 7 and 12 years of age participated in the present study. Handwriting quality was evaluated through the Minnesota Handwriting Assessment. Only the experimental group (n=18 was submitted to the intervention program developed throughout 27 sessions of 30 minutes each. The results indicate that the intervention program based on the variability of force production had a positive effect on the quality of handwriting,mainly in terms of the size of letters.

  18. FxLMS Method for Suppressing In-Wheel Switched Reluctance Motor Vertical Force Based on Vehicle Active Suspension System

    Directory of Open Access Journals (Sweden)

    Yan-yang Wang

    2014-01-01

    Full Text Available The vibration of SRM obtains less attention for in-wheel motor applications according to the present research works. In this paper, the vertical component of SRM unbalanced radial force, which is named as SRM vertical force, is taken into account in suspension performance for in-wheel motor driven electric vehicles (IWM-EV. The analysis results suggest that SRM vertical force has a great effect on suspension performance. The direct cause for this phenomenon is that SRM vertical force is directly exerted on the wheel, which will result in great variation in tyre dynamic load and the tyre will easily jump off the ground. Furthermore, the frequency of SRM vertical force is broad which covers the suspension resonance frequencies. So it is easy to arouse suspension resonance and greatly damage suspension performance. Aiming at the new problem, FxLMS (filtered-X least mean square controller is proposed to improve suspension performance. The FxLMS controller is based on active suspension system which can generate the controllable force to suppress the vibration caused by SRM vertical force. The conclusion shows that it is effective to take advantage of active suspensions to reduce the effect of SRM vertical force on suspension performance.

  19. A Predictive Model of Cell Traction Forces Based on Cell Geometry

    OpenAIRE

    Lemmon, Christopher A.; Romer, Lewis H

    2010-01-01

    Recent work has indicated that the shape and size of a cell can influence how a cell spreads, develops focal adhesions, and exerts forces on the substrate. However, it is unclear how cell shape regulates these events. Here we present a computational model that uses cell shape to predict the magnitude and direction of forces generated by cells. The predicted results are compared to experimentally measured traction forces, and show that the model can predict traction force direction, relative m...

  20. Effectiveness of an Individualized Training Based on Force-Velocity Profiling during Jumping

    Science.gov (United States)

    Jiménez-Reyes, Pedro; Samozino, Pierre; Brughelli, Matt; Morin, Jean-Benoît

    2017-01-01

    Ballistic performances are determined by both the maximal lower limb power output (Pmax) and their individual force-velocity (F-v) mechanical profile, especially the F-v imbalance (FVimb): difference between the athlete's actual and optimal profile. An optimized training should aim to increase Pmax and/or reduce FVimb. The aim of this study was to test whether an individualized training program based on the individual F-v profile would decrease subjects' individual FVimb and in turn improve vertical jump performance. FVimb was used as the reference to assign participants to different training intervention groups. Eighty four subjects were assigned to three groups: an “optimized” group divided into velocity-deficit, force-deficit, and well-balanced sub-groups based on subjects' FVimb, a “non-optimized” group for which the training program was not specifically based on FVimb and a control group. All subjects underwent a 9-week specific resistance training program. The programs were designed to reduce FVimb for the optimized groups (with specific programs for sub-groups based on individual FVimb values), while the non-optimized group followed a classical program exactly similar for all subjects. All subjects in the three optimized training sub-groups (velocity-deficit, force-deficit, and well-balanced) increased their jumping performance (12.7 ± 5.7% ES = 0.93 ± 0.09, 14.2 ± 7.3% ES = 1.00 ± 0.17, and 7.2 ± 4.5% ES = 0.70 ± 0.36, respectively) with jump height improvement for all subjects, whereas the results were much more variable and unclear in the non-optimized group. This greater change in jump height was associated with a markedly reduced FVimb for both force-deficit (57.9 ± 34.7% decrease in FVimb) and velocity-deficit (20.1 ± 4.3%) subjects, and unclear or small changes in Pmax (−0.40 ± 8.4% and +10.5 ± 5.2%, respectively). An individualized training program specifically based on FVimb (gap between the actual and optimal F-v profiles of

  1. A review of measurement-based assessments of the aerosol direct radiative effect and forcing

    Directory of Open Access Journals (Sweden)

    H. Yu

    2006-01-01

    Full Text Available Aerosols affect the Earth's energy budget directly by scattering and absorbing radiation and indirectly by acting as cloud condensation nuclei and, thereby, affecting cloud properties. However, large uncertainties exist in current estimates of aerosol forcing because of incomplete knowledge concerning the distribution and the physical and chemical properties of aerosols as well as aerosol-cloud interactions. In recent years, a great deal of effort has gone into improving measurements and datasets. It is thus feasible to shift the estimates of aerosol forcing from largely model-based to increasingly measurement-based. Our goal is to assess current observational capabilities and identify uncertainties in the aerosol direct forcing through comparisons of different methods with independent sources of uncertainties. Here we assess the aerosol optical depth (τ, direct radiative effect (DRE by natural and anthropogenic aerosols, and direct climate forcing (DCF by anthropogenic aerosols, focusing on satellite and ground-based measurements supplemented by global chemical transport model (CTM simulations. The multi-spectral MODIS measures global distributions of aerosol optical depth (τ on a daily scale, with a high accuracy of ±0.03±0.05τ over ocean. The annual average τ is about 0.14 over global ocean, of which about 21%±7% is contributed by human activities, as estimated by MODIS fine-mode fraction. The multi-angle MISR derives an annual average AOD of 0.23 over global land with an uncertainty of ~20% or ±0.05. These high-accuracy aerosol products and broadband flux measurements from CERES make it feasible to obtain observational constraints for the aerosol direct effect, especially over global the ocean. A number of measurement-based approaches estimate the clear-sky DRE (on solar radiation at the top-of-atmosphere (TOA to be about -5.5±0.2 Wm-2 (median ± standard error from various methods over the global ocean. Accounting for thin cirrus

  2. Barnacle muscle: Ca2+, activation and mechanics.

    Science.gov (United States)

    Ashley, C C; Griffiths, P J; Lea, T J; Mulligan, I P; Palmer, R E; Simnett, S J

    1993-01-01

    In this review, aspects of the ways in which Ca2+ is transported and regulated within muscle cells have been considered, with particular reference to crustacean muscle fibres. The large size of these fibres permits easy access to the internal environment of the cell, allowing it to be altered by microinjection or microperfusion. At rest, Ca2+ is not in equilibrium across the cell membrane, it enters the cell down a steep electrochemical gradient. The free [Ca2+] at rest is maintained at a value close to 200 nM by a combination of internal buffering systems, mainly the SR, mitochondria, and the fixed and diffusible Ca(2+)-binding proteins, as well as by an energy-dependent extrusion system operating across the external cell membrane. This system relies upon the inward movement of Na+ down its own electrochemical gradient to provide the energy for the extrusion of Ca2+ ions. As a result of electrical excitation, voltage-sensitive channels for Ca2+ are activated and permit Ca2+ to enter the cell more rapidly than at rest. It has been possible to determine both the amount of Ca2+ entering by this step, and what part this externally derived Ca2+ plays in the development of force as well as in the free Ca2+ change. The latter can be determined directly by Ca(2+)-sensitive indicators introduced into the cell sarcoplasm. A combination of techniques, allowing both the total and free Ca2+ changes to be assessed during electrical excitation, has provided valuable information as to how muscle cells buffer their Ca2+ in order to regulate the extent of the change in the free Ca2+ concentration. The data indicate that the entering Ca2+ can only make a small direct contribution to the force developed by the cell. The implication here is that the major source of Ca2+ for contraction must be derived from the internal Ca2+ storage sites within the SR system, a view reinforced by caged Ca2+ methods. The ability to measure the free Ca2+ concentration changes within a single cell during

  3. Meta-Analysis of Cell-based CaRdiac stUdiEs (ACCRUE) in patients with acute myocardial infarction based on individual patient data

    DEFF Research Database (Denmark)

    Gyöngyösi, Mariann; Wojakowski, Wojciech; Lemarchand, Patricia

    2015-01-01

    RATIONALE: The meta-Analysis of Cell-based CaRdiac study is the first prospectively declared collaborative multinational database, including individual data of patients with ischemic heart disease treated with cell therapy. OBJECTIVE: We analyzed the safety and efficacy of intracoronary cell ther...... randomized trials in patients with recent AMI revealed that intracoronary cell therapy provided no benefit, in terms of clinical events or changes in left ventricular function. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01098591....

  4. Endosome-based protein trafficking and Ca2+ homeostasis in the heart

    Directory of Open Access Journals (Sweden)

    Jerry eCurran

    2015-02-01

    Full Text Available The ability to dynamically regulate, traffic, retain, and recycle proteins within the cell membrane is fundamental to life and central to the normal function of the heart and cardiovascular system. In the heart, these systems are essential for the regulation of cardiac calcium, both at the level of the plasma membrane, but also at local domains of the endoplasmic reticulum, sarcoplasmic reticulum, mitochondria, nucleus, and nuclear envelope. One intracellular pathway often overlooked in relation to cardiovascular calcium regulation and signaling is the endosome-based trafficking pathway. Highlighting its importance, this system and its molecular components are evolutionarily conserved across all metazoans. However, remarkably little is known of how endosome-based protein trafficking and recycling functions within mammalian cells systems, especially in the heart. The vast majority of what is known has been derived from heterologous cell systems. However, recently, more appropriate cell and animal models been developed that have allowed researchers to begin to understand how this system functions within the intact physiological environment. All excitable cells, including cardiomyocytes, depend on the proper expression and organization of multiple ion channels, pumps, exchangers, and transporters within the plasma membrane. As the endosomal system acts to regulate the expression and localization of membrane proteins, understanding the in vivo function of this system in the heart is important. This review will focus on endosome-based protein trafficking in the heart in both health and disease. Special emphasis will be given to the role played by the family of endocytic regulatory proteins, C-terminal Eps15 homology domain -containing proteins (EHDs, as recent data demonstrates that this family of proteins is essential for the proper trafficking and localization and of key proteins involved in excitation-contraction coupling.

  5. Aequorin-based measurements of intracellular Ca2+-signatures in plant cells

    Directory of Open Access Journals (Sweden)

    Mithöfer Axel

    2002-01-01

    Full Text Available Due to the involvement of calcium as a main second messenger in the plant signaling pathway, increasing interest has been focused on the calcium signatures supposed to be involved in the patterning of the specific response associated to a given stimulus. In order to follow these signatures we described here the practical approach to use the non-invasive method based on the aequorin technology. Besides reviewing the advantages and disadvantages of this method we report on results showing the usefulness of aequorin to study the calcium response to biotic (elicitors and abiotic stimuli (osmotic shocks in various compartments of plant cells such as cytosol and nucleus.

  6. Ridit Analysis for Cooper-Harper and Other Ordinal Ratings for Sparse Data - A Distance-based Approach

    Science.gov (United States)

    2016-09-01

    based Approach ARNON HURWITZ, PhD AIR FORCE TEST CENTER EDWARDS AFB, CA SEPTEMBER 2016 4 1 2 T W C m Approved...for public release; distribution is unlimited. 412TW-PA-16437 412TH TEST WING EDWARDS AIR FORCE BASE , CALIFORNIA AIR FORCE MATERIEL COMMAND...Office Edwards Air Force Base Building 1440, #115 E. Popson Avenue Edwards

  7. A Three-Dimensional Shape-Based Force and Stiffness-Sensing Platform for Tendon-Driven Catheters

    Directory of Open Access Journals (Sweden)

    Minou Kouh Soltani

    2016-06-01

    Full Text Available This paper presents an efficient shape-based three-axial force and stiffness estimator for active catheters commonly implemented in cardiac ablation. The force-sensing capability provides important feedback for catheterization procedures including real-time control and catheter steering in autonomous navigation systems. The proposed platform is based on the introduced accurate and computationally efficient Cosserat rod model for tendon-driven catheters. The proposed nonlinear Kalman filter formulation for contact force estimation along with the developed catheter model provides a real-time force observer robust to nonlinearities and noise covariance uncertainties. Furthermore, the proposed platform enables stiffness estimation in addition to tip contact force sensing in different operational circumstances. The approach incorporates pose measurements which can be achieved using currently developed pose-sensing systems or imaging techniques. The method makes the approach compatible with the range of forces applied in clinical applications. The simulation and experimental results verify the viability of the introduced force and stiffness-sensing technique.

  8. A Three-Dimensional Shape-Based Force and Stiffness-Sensing Platform for Tendon-Driven Catheters

    Science.gov (United States)

    Kouh Soltani, Minou; Khanmohammadi, Sohrab; Ghalichi, Farzan

    2016-01-01

    This paper presents an efficient shape-based three-axial force and stiffness estimator for active catheters commonly implemented in cardiac ablation. The force-sensing capability provides important feedback for catheterization procedures including real-time control and catheter steering in autonomous navigation systems. The proposed platform is based on the introduced accurate and computationally efficient Cosserat rod model for tendon-driven catheters. The proposed nonlinear Kalman filter formulation for contact force estimation along with the developed catheter model provides a real-time force observer robust to nonlinearities and noise covariance uncertainties. Furthermore, the proposed platform enables stiffness estimation in addition to tip contact force sensing in different operational circumstances. The approach incorporates pose measurements which can be achieved using currently developed pose-sensing systems or imaging techniques. The method makes the approach compatible with the range of forces applied in clinical applications. The simulation and experimental results verify the viability of the introduced force and stiffness-sensing technique. PMID:27367685

  9. Factors which influence on force of boxers` and footballers` shots on the stage of base pre-treatment

    Directory of Open Access Journals (Sweden)

    Nikitenko S.A.

    2011-02-01

    Full Text Available On the stage of base pre-treatment factors which influence on force of shots the hands of boxers and feet of footballers as a criterion of competition activity efficiency are certain. Connections are certain between force of shots by hands and feet. The objective test of the specialized sense determination of boxers` and footballers` shots is offered. It is recommended to develop maximal and explosive force of all parts of sportsman body at implementation preparatory exercises with the further transfer of physical qualities on implementation of the special exercises.

  10. Improving estimates of aerosol radiative forcing through a particle-based aerosol microphysical scheme

    Science.gov (United States)

    Fierce, L.; McGraw, R. L.

    2016-12-01

    Forcing by atmospheric aerosols remains a large source of uncertainty in assessing human influences on the climate. Although global models have moved toward including more detailed representations of aerosol populations, aerosol microphysical schemes have been evaluated against benchmark models in only limited cases. Here we introduce a new framework for simulating atmospheric aerosols based on the Quadrature Method of Moments. This new aerosol model has been designed to reproduce key features of benchmark populations simulated by the particle-resolved model PartMC-MOSAIC, while tracking as little information about aerosol distributions as is necessary. The quadrature-based model simulates the aerosol evolution using a small number of weighted particles and is, therefore, decided as a reduced particle-based model. By applying principles of maximum entropy, the quadrature-based model efficiently reproduces distributions with respect to key aerosol properties, such as critical supersaturation for cloud condensation nuclei activation and optical cross sections, with high accuracy. In addition to providing an optimized aerosol model, the present study also describes how multi-scale modeling can be used as a tool for development of advanced aerosol microphysical schemes.

  11. Force-based and displacement-based reliability assessment approaches for highway bridges under multiple hazard actions

    Directory of Open Access Journals (Sweden)

    Chao Huang

    2015-08-01

    Full Text Available The strength limit state of American Association of State Highway and Transportation Officials (AASHTO Load and Resistance Factor Design (LRFD Bridge Design Specifications is developed based on the failure probabilities of the combination of non-extreme loads. The proposed design limit state equation (DLSE has been fully calibrated for dead load and live load by using the reliability-based approach. On the other hand, most of DLSEs in other limit states, including the extreme events Ⅰ and Ⅱ, have not been developed and calibrated though taking certain probability-based concepts into account. This paper presents an assessment procedure of highway bridge reliabilities under the limit state of extreme event Ⅰ, i. e., the combination of dead load, live load and earthquake load. A force-based approach and a displacement-based approach are proposed and implemented on a set of nine simplified bridge models. Results show that the displacement-based approach comes up with more convergent and accurate reliabilities for selected models, which can be applied to other hazards.

  12. Sonic booms of space shuttles approaching Edwards Air Force Base, 1988-1993

    Science.gov (United States)

    Young, Robert W.

    2002-01-01

    From 1988 to 1993 13 sonic booms of space shuttles approaching Edwards Air Force Base were measured at a site 10 miles west of EAFB, with one to seven different sound level meters for each measurement. Results from five of these measurements are here presented. Maximum differences in measured levels between instruments for the same flight varied from 0 to 6 dB depending on the measurement descriptor and model of sound level meter. The average difference between predicted and measured values was 0.7+/-1.5 dB. For sound level meters with adequate bandwidth the waveforms measured varied from a near perfect N-wave to a more distorted form reflecting the influence of the varying condition of the atmosphere during propagation to the ground.

  13. Hot, cold, and annual reference atmospheres for Edwards Air Force Base, California (1975 version)

    Science.gov (United States)

    Johnson, D. L.

    1975-01-01

    Reference atmospheres pertaining to summer (hot), winter (cold), and mean annual conditions for Edwards Air Force Base, California, are presented from surface to 90 km altitude (700 km for the annual model). Computed values of pressure, kinetic temperature, virtual temperature, and density and relative differences percentage departure from the Edwards reference atmospheres, 1975 (ERA-75) of the atmospheric parameters versus altitude are tabulated in 250 m increments. Hydrostatic and gas law equations were used in conjunction with radiosonde and rocketsonde thermodynamic data in determining the vertical structure of these atmospheric models. The thermodynamic parameters were all subjected to a fifth degree least-squares curve-fit procedure, and the resulting coefficients were incorporated into Univac 1108 computer subroutines so that any quantity may be recomputed at any desired altitude using these subroutines.

  14. System design and new applications for atomic force microscope based on tunneling

    Science.gov (United States)

    Wang, X.; Liu, A. P.; Yang, X. H.

    2015-09-01

    The design of atomic force microscopy (AFM) with high resolution is introduced in this paper. Mainly, we have developed the system design of the apparatus based on tunneling. AFM.IPC-208B, this kind of apparatus combines scanning tunnel microscopy (STM) and AFM availability, and its lens body with original frame enhances the capability of the machine. In order to analyze the performance of AFM.IPC-208B, as a new tool in the field of Life Science, we make use of the system to study natural mica and molecular protein structures of Cattle-insulin and human antibody immunoglobulin G (IgG) coupled with staphylococcus protein A (SPA). As the results of new applications, the resolution of AFM.IPC-208B is proved to be 0.1 nm, and these nanometer measurement results provide much valuable information for the study of small molecular proteins and HIV experiments.

  15. Forced degradation studies: current trends and future perspectives for protein-based therapeutics.

    Science.gov (United States)

    Chan, Christine P

    2016-07-01

    Forced degradation (FD) studies (stress testing) are an integral part of pharmaceutical product development. The design and execution of these studies require thorough planning and coordination through the various stages of development as well as post-approval commercial operations. This is particularly crucial in the case for protein-based therapeutics due to complexity of the molecular structure as well as the potential influence of the manufacturing process on product attributes. Often, FD study applications are linked to specific product development in a phase-specific and case-by-case manner with differing purposes and focus. Expert commentary: This paper summarizes some key FD approaches commonly employed in the industry and provides considerations on study design strategies and database management through the course of the product lifecycle.

  16. Active diffusion and microtubule-based transport oppose myosin forces to position organelles in cells

    Science.gov (United States)

    Lin, Congping; Schuster, Martin; Guimaraes, Sofia Cunha; Ashwin, Peter; Schrader, Michael; Metz, Jeremy; Hacker, Christian; Gurr, Sarah Jane; Steinberg, Gero

    2016-06-01

    Even distribution of peroxisomes (POs) and lipid droplets (LDs) is critical to their role in lipid and reactive oxygen species homeostasis. How even distribution is achieved remains elusive, but diffusive motion and directed motility may play a role. Here we show that in the fungus Ustilago maydis ~95% of POs and LDs undergo diffusive motions. These movements require ATP and involve bidirectional early endosome motility, indicating that microtubule-associated membrane trafficking enhances diffusion of organelles. When early endosome transport is abolished, POs and LDs drift slowly towards the growing cell end. This pole-ward drift is facilitated by anterograde delivery of secretory cargo to the cell tip by myosin-5. Modelling reveals that microtubule-based directed transport and active diffusion support distribution, mobility and mixing of POs. In mammalian COS-7 cells, microtubules and F-actin also counteract each other to distribute POs. This highlights the importance of opposing cytoskeletal forces in organelle positioning in eukaryotes.

  17. Minimally invasive intracellular delivery based on electrokinetic forces combined with vibration-assisted cell membrane perforation

    Science.gov (United States)

    Shibata, Takayuki; Ozawa, Tatsuya; Ito, Yasuharu; Yamamoto, Keita; Nagai, Moeto

    2017-01-01

    To provide an effective platform for the fundamental analysis of cellular mechanisms and the regulation of cellular functions, we developed a unique method of minimally invasive intracellular delivery. Using this method, we successfully demonstrated the delivery of DNA molecules into living HeLa cells via a glass micropipette based on DC-biased AC-driven electrokinetic forces with much better controllability than that of the pressure-driven flow method. We also proposed a vibration-assisted insertion method for penetrating the cell membrane to reduce cell damage. Preliminary insertion tests revealed that application of mechanical oscillation can reduce the deformation of cells due to increases in their viscous resistance, resulting in a high probability of cell membrane perforation and cell viability. Moreover, to overcome the intrinsic low throughput of intracellular delivery with a single glass micropipette, we developed a fabrication process involving an array of stepped hollow silicon dioxide (SiO2) nanoneedles with well-defined tips.

  18. Atomic Force Microscopy-based Cell Nanostructure for Ligand-conjugated Quantum Dot Endocytosis

    Institute of Scientific and Technical Information of China (English)

    Yun-Long PAN; Ji-Ye CAI; Li QIN; Hao WANG

    2006-01-01

    While it has been well demonstrated that quantum dots (QDs) play an important role in biological labeling both in vitro and in vivo,there is no report describing the cellular nanostructure basis of receptor-mediated endocytosis. Here, nanostructure evolution responses to the endocytosis of transferrin force microscopy (AFM). AFM-based nanostructure analysis demonstrated that the Tf-conjugated QDs were specifically and tightly bound to the cell receptors rrelated with the cell membrane receptor-mediated transduction.Consistently, confocal microscopic and flow cytometry results have demonstrated the specificity and the internalization of Tf-QD is linearly related to time. Moreover, while the nanoparticles on the cell membrane increased, the endocytosis was still nanoparticles did not interfere sterically with the binding and function of receptors. Therefore, ligand-conjugated QDs are potentially useful in biological labeling of cells at a nanometer scale.

  19. Application of Base Force Element Method to Mesomechanics Analysis for Recycled Aggregate Concrete

    Directory of Open Access Journals (Sweden)

    Yijiang Peng

    2013-01-01

    Full Text Available The base force element method (BFEM on potential energy principle is used to analyze recycled aggregate concrete (RAC on mesolevel. The model of BFEM with triangular element is derived. The recycled aggregate concrete is taken as five-phase composites consisting of natural coarse aggregate, new mortar, new interfacial transition zone (ITZ, old mortar, and old ITZ on meso-level. The random aggregate model is used to simulate the mesostructure of recycled aggregate concrete. The mechanics properties of uniaxial compression and tension tests for RAC are simulated using the BFEM, respectively. The simulation results agree with the test results. This research method is a new way for investigating fracture mechanism and numerical simulation of mechanics properties for recycled aggregate concrete.

  20. Study of SAW Based on a Micro Force Sensor in Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2017-01-01

    Full Text Available Wireless sensor network (WSN technology has increasingly assumed an active role in detection, identification, location, and tracking applications after more than ten years of development. However, its application still suffers from technology bottlenecks, which must be solved and perfected to eliminate the key problems of the technology. This article investigates WSN acquisition nodes and analyzes the relationship between the frequency and actual pressure values of sensor nodes. The sensitive mechanism of the surface acoustic wave (SAW based on a micro force sensor is researched, and the principle of least squares method is used to establish a transformation model of frequency and pressure for the SAW sensor. According to the model, polyfit function and matrix calculation are selected to solve and calculate the estimate of the polynomial coefficients, which simulate the data acquisition of WSN nodes and draw a polynomial curve fitting. The actual SAW sensor is tested to demonstrate the reasonableness of the device stability in WSNs.

  1. The possibility of multi-layer nanofabrication via atomic force microscope-based pulse electrochemical nanopatterning.

    Science.gov (United States)

    Kim, Uksu; Morita, Noboru; Lee, Deug; Jun, Martin; Park, Jeong Woo

    2017-03-27

    Pulse electrochemical nanopatterning (PECN), a non-contact scanning probe lithography (NC-SPL) process using ultrashort voltage pulses, is based primarily on an electrochemical machining (ECM) process using localized electrochemical oxidation between a sharp tool tip and the sample surface. In this study, nanoscale oxide patterns were formed on silicon Si (100) wafer surfaces via electrochemical surface nanopatterning, by supplying external pulsed currents through non-contact atomic force microscopy. Nanoscale oxide width and height were controlled by modulating the applied pulse duration. Additionally, protruding nanoscale oxides were removed completely by simple chemical etching, showing a depressed pattern on the sample substrate surface. Nanoscale two-dimensional oxides, prepared by a localized electrochemical reaction, can be defined easily by controlling physical and electrical variables, before proceeding further to a layer-by-layer nanofabrication process.

  2. Improved social force model based on exit selection for microscopic pedestrian simulation in subway station

    Institute of Scientific and Technical Information of China (English)

    郑勋; 李海鹰; 孟令云; 许心越; 陈旭

    2015-01-01

    An improved social force model based on exit selection is proposed to simulate pedestrians’ microscopic behaviors in subway station. The modification lies in considering three factors of spatial distance, occupant density and exit width. In addition, the problem of pedestrians selecting exit frequently is solved as follows: not changing to other exits in the affected area of one exit, using the probability of remaining preceding exit and invoking function of exit selection after several simulation steps. Pedestrians in subway station have some special characteristics, such as explicit destinations, different familiarities with subway station. Finally, Beijing Zoo Subway Station is taken as an example and the feasibility of the model results is verified through the comparison of the actual data and simulation data. The simulation results show that the improved model can depict the microscopic behaviors of pedestrians in subway station.

  3. Active diffusion and microtubule-based transport oppose myosin forces to position organelles in cells

    Science.gov (United States)

    Lin, Congping; Schuster, Martin; Guimaraes, Sofia Cunha; Ashwin, Peter; Schrader, Michael; Metz, Jeremy; Hacker, Christian; Gurr, Sarah Jane; Steinberg, Gero

    2016-01-01

    Even distribution of peroxisomes (POs) and lipid droplets (LDs) is critical to their role in lipid and reactive oxygen species homeostasis. How even distribution is achieved remains elusive, but diffusive motion and directed motility may play a role. Here we show that in the fungus Ustilago maydis ∼95% of POs and LDs undergo diffusive motions. These movements require ATP and involve bidirectional early endosome motility, indicating that microtubule-associated membrane trafficking enhances diffusion of organelles. When early endosome transport is abolished, POs and LDs drift slowly towards the growing cell end. This pole-ward drift is facilitated by anterograde delivery of secretory cargo to the cell tip by myosin-5. Modelling reveals that microtubule-based directed transport and active diffusion support distribution, mobility and mixing of POs. In mammalian COS-7 cells, microtubules and F-actin also counteract each other to distribute POs. This highlights the importance of opposing cytoskeletal forces in organelle positioning in eukaryotes. PMID:27251117

  4. Throughput and delay analysis of IEEE 802.15.6-based CSMA/CA protocol.

    Science.gov (United States)

    Ullah, Sana; Chen, Min; Kwak, Kyung Sup

    2012-12-01

    The IEEE 802.15.6 is a new communication standard on Wireless Body Area Network (WBAN) that focuses on a variety of medical, Consumer Electronics (CE) and entertainment applications. In this paper, the throughput and delay performance of the IEEE 802.15.6 is presented. Numerical formulas are derived to determine the maximum throughput and minimum delay limits of the IEEE 802.15.6 for an ideal channel with no transmission errors. These limits are derived for different frequency bands and data rates. Our analysis is validated by extensive simulations using a custom C+ + simulator. Based on analytical and simulation results, useful conclusions are derived for network provisioning and packet size optimization for different applications.

  5. Driving forces for home-based reablement; a qualitative study of older adults' experiences.

    Science.gov (United States)

    Hjelle, Kari Margrete; Tuntland, Hanne; Førland, Oddvar; Alvsvåg, Herdis

    2017-09-01

    As a result of the ageing population worldwide, there has been a growing international interest in a new intervention termed 'reablement'. Reablement is an early and time-limited home-based intervention with emphasis on intensive, goal-oriented and interdisciplinary rehabilitation for older adults in need of rehabilitation or at risk of functional decline. The aim of this qualitative study was to describe how older adults experienced participation in reablement. Eight older adults participated in semi-structured interviews. A qualitative content analysis was used as the analysis strategy. Four main themes emerged from the participants' experiences of participating in reablement: 'My willpower is needed', 'Being with my stuff and my people', 'The home-trainers are essential', and 'Training is physical exercises, not everyday activities'. The first three themes in particular reflected the participants' driving forces in the reablement process. Driving forces are intrinsic motivation in interaction with extrinsic motivation. Intrinsic motivation was based on the person's willpower and responsibility, and extrinsic motivation was expressed to be strengthened by being in one's home environment with 'own' people, as well as by the co-operation with the reablement team. The reablement team encouraged and supported the older adults to regain confidence in performing everyday activities as well as participating in the society. Our findings have practical significance for politicians, healthcare providers and healthcare professionals by contributing to an understanding of how intrinsic and extrinsic motivation influence reablement. Some persons need apparently more extrinsic motivational support also after the time-limited reablement period is completed. The municipal health and care services need to consider individualised follow-up programmes after the intensive reablement period in order to maintain the achieved skills to perform everyday activities and participate in

  6. Escherichia coli removal from model substrates: Underlying mechanism based on nanofluid structural forces.

    Science.gov (United States)

    Shim, Jiyoung; Nikolov, Alex; Wasan, Darsh

    2017-07-15

    Understanding the interactions between bacteria and solid surfaces that result in bacterial adhesion and removal is of immense importance for reducing foodborne illness outbreaks. A nanofluid formulation comprised of a sodium dodecyl sulfate (SDS) micellar aqueous solution in the presence of an organic acid (as a pH controller) was used to test the E. coli K12 removal from two substrates, polyvinylchloride (PVC) and partially hydrophobic glass. We investigated the bacterial removal efficacy based on the combined effect of the nanofluid's structural forces and bacterial isoelectric point. To quantify the bacteria-PVC coverage, we used fluorescence microscope. The Langmuir isotherm at the low volume fraction was applied to estimate the adsorption energy of E. coli K12. We obtained a value of about 2.5±0.2kT. This value compared favorably with the value of 2.1kT reported previously for E. coli NCTC 9002 (Vanloosdrecht et al., 1989). We applied the dynamic light scattering method to estimate the radius of the gyration of E. coli K12. The radius of the gyration was used to estimate the limit of surface area covered by the bacterium and compared it to the surface area measured from the image taken with fluorescence microscope. We found that they are in good agreement with each other. We modeled the nanofluid oscillatory structural energy against the E. coli K12 adsorption energy by applying the statistical mechanics approach. Based on the model prediction, the oscillatory interaction energy was estimated at the vertex between a bacterium and the substrate (i.e., the wedge film's interaction energy at one particle layer). The evaluated film's repulsive energy due to the oscillatory structural forces (OSF) was about 15.6±4.4kT of the 0.02M SMNF (the SDS micellar nanofluid formulation) and several times higher than the bacterial adsorption energy, 2.5±0.2kT. The OSF of the 0.06M SMNF was measured by AFM (the oscillatory decay force curve). The period and number of

  7. Inseparable tandem: evolution chooses ATP and Ca2+ to control life, death and cellular signalling.

    Science.gov (United States)

    Plattner, Helmut; Verkhratsky, Alexei

    2016-08-05

    From the very dawn of biological evolution, ATP was selected as a multipurpose energy-storing molecule. Metabolism of ATP required intracellular free Ca(2+) to be set at exceedingly low concentrations, which in turn provided the background for the role of Ca(2+) as a universal signalling molecule. The early-eukaryote life forms also evolved functional compartmentalization and vesicle trafficking, which used Ca(2+) as a universal signalling ion; similarly, Ca(2+) is needed for regulation of ciliary and flagellar beat, amoeboid movement, intracellular transport, as well as of numerous metabolic processes. Thus, during evolution, exploitation of atmospheric oxygen and increasingly efficient ATP production via oxidative phosphorylation by bacterial endosymbionts were a first step for the emergence of complex eukaryotic cells. Simultaneously, Ca(2+) started to be exploited for short-range signalling, despite restrictions by the preset phosphate-based energy metabolism, when both phosphates and Ca(2+) interfere with each other because of the low solubility of calcium phosphates. The need to keep cytosolic Ca(2+) low forced cells to restrict Ca(2+) signals in space and time and to develop energetically favourable Ca(2+) signalling and Ca(2+) microdomains. These steps in tandem dominated further evolution. The ATP molecule (often released by Ca(2+)-regulated exocytosis) rapidly grew to be the universal chemical messenger for intercellular communication; ATP effects are mediated by an extended family of purinoceptors often linked to Ca(2+) signalling. Similar to atmospheric oxygen, Ca(2+) must have been reverted from a deleterious agent to a most useful (intra- and extracellular) signalling molecule. Invention of intracellular trafficking further increased the role for Ca(2+) homeostasis that became critical for regulation of cell survival and cell death. Several mutually interdependent effects of Ca(2+) and ATP have been exploited in evolution, thus turning an originally

  8. A Certificate Authority (CA-based cryptographic solution for HIPAA privacy/security regulations

    Directory of Open Access Journals (Sweden)

    Sangram Ray

    2014-07-01

    Full Text Available The Health Insurance Portability and Accountability Act (HIPAA passed by the US Congress establishes a number of privacy/security regulations for e-healthcare systems. These regulations support patients’ medical privacy and secure exchange of PHI (protected health information among medical practitioners. Three existing HIPAA-based schemes have been studied but appear to be ineffective as patients’ PHI is stored in smartcards. Moreover, carrying a smartcard during a treatment session and accessing PHI from different locations results in restrictions. In addition, authentication of the smartcard presenter would not be possible if the PIN is compromised. In this context, we propose an MCS (medical center server should be located at each hospital and accessed via the Internet for secure handling of patients’ PHI. All entities of the proposed e-health system register online with the MCS, and each entity negotiates a contributory registration key, where public-key certificates issued and maintained by CAs are used for authentication. Prior to a treatment session, a doctor negotiates a secret session key with MCS and uploads/retrieves patients’ PHI securely. The proposed scheme has five phases, which have been implemented in a secure manner for supporting HIPAA privacy/security regulations. Finally, the security aspects, computation and communication costs of the scheme are analyzed and compared with existing methods that display satisfactory performance.

  9. Reducing the cost of Ca-based direct air capture of CO2.

    Science.gov (United States)

    Zeman, Frank

    2014-10-07

    Direct air capture, the chemical removal of CO2 directly from the atmosphere, may play a role in mitigating future climate risk or form the basis of a sustainable transportation infrastructure. The current discussion is centered on the estimated cost of the technology and its link to "overshoot" trajectories, where atmospheric CO2 levels are actively reduced later in the century. The American Physical Society (APS) published a report, later updated, estimating the cost of a one million tonne CO2 per year air capture facility constructed today that highlights several fundamental concepts of chemical air capture. These fundamentals are viewed through the lens of a chemical process that cycles between removing CO2 from the air and releasing the absorbed CO2 in concentrated form. This work builds on the APS report to investigate the effect of modifications to the air capture system based on suggestions in the report and subsequent publications. The work shows that reduced carbon electricity and plastic packing materials (for the contactor) may have significant effects on the overall price, reducing the APS estimate from $610 to $309/tCO2 avoided. Such a reduction does not challenge postcombustion capture from point sources, estimated at $80/tCO2, but does make air capture a feasible alternative for the transportation sector and a potential negative emissions technology. Furthermore, air capture represents atmospheric reductions rather than simply avoided emissions.

  10. REMOVAL OF H2S AND SO2 BY CaCO3-BASED SORBENTS AT HIGH PRESSURES

    Energy Technology Data Exchange (ETDEWEB)

    Prof. Stratis V. Sotirchos

    2000-09-01

    The mechanism of the removal of SO{sub 2} and H{sub 2}S by CaCO{sub 3}-based sorbents in pressurized fluidized-bed coal combustors (PFBC) and high pressure gasifiers was investigated in this project. Reactivity evolution experiments were carried out in thermogravimetric apparatuses both under simulated high pressure conditions and at high pressures. Experiments at high pressure were conducted in a high pressure thermogravimetric arrangement that was set up and developed under this project. Two calcitic solids of high calcium carbonate content (over 97%) were employed in the experiments: a fine-grained distributed by Greer Limestone Co. (Greer Limestone) and a solid supplied in the form of large calcitic crystals (Iceland Spar). The decision to work with these solids was mainly based on the fact that they have been employed in several past studies of sulfation, sulfidation, and calcination in our laboratory, and therefore, a large volume of data on their performance under different conditions was available for comparison purposes. In addition to the experimental studies, work was also done on the development of rigorous mathematical models for the description of the occurrence of simultaneous processes (e.g., calcination and sulfation and carbonation and sulfation) in the interior of porous solids and for the simulation of the evolution of the pore structure of porous solids that undergo chemical transformation in their interior.

  11. Soil erosion and causative factors at Vandenberg Air Force Base, California

    Science.gov (United States)

    Butterworth, Joel B.

    1988-01-01

    Areas of significant soil erosion and unvegetated road cuts were identified and mapped for Vandenberg Air Force Base. One hundred forty-two eroded areas (most greater than 1.2 ha) and 51 road cuts were identified from recent color infrared aerial photography and ground truthed to determine the severity and causes of erosion. Comparison of the present eroded condition of soils (as shown in the 1986 photography) with that in historical aerial photography indicates that most erosion on the base took place prior to 1928. However, at several sites accelerated rates of erosion and sedimentation may be occurring as soils and parent materials are eroded vertically. The most conspicuous erosion is in the northern part of the base, where severe gully, sheet, and mass movement erosion have occurred in soils and in various sedimentary rocks. Past cultivation practices, compounded by highly erodible soils prone to subsurface piping, are probably the main causes. Improper range management practices following cultivation may have also increased runoff and erosion. Aerial photography from 1986 shows that no appreciable headward erosion or gully sidewall collapse have occurred in this area since 1928.

  12. Force sensor based tool condition monitoring using a heterogeneous ensemble learning model.

    Science.gov (United States)

    Wang, Guofeng; Yang, Yinwei; Li, Zhimeng

    2014-11-14

    Tool condition monitoring (TCM) plays an important role in improving machining efficiency and guaranteeing workpiece quality. In order to realize reliable recognition of the tool condition, a robust classifier needs to be constructed to depict the relationship between tool wear states and sensory information. However, because of the complexity of the machining process and the uncertainty of the tool wear evolution, it is hard for a single classifier to fit all the collected samples without sacrificing generalization ability. In this paper, heterogeneous ensemble learning is proposed to realize tool condition monitoring in which the support vector machine (SVM), hidden Markov model (HMM) and radius basis function (RBF) are selected as base classifiers and a stacking ensemble strategy is further used to reflect the relationship between the outputs of these base classifiers and tool wear states. Based on the heterogeneous ensemble learning classifier, an online monitoring system is constructed in which the harmonic features are extracted from force signals and a minimal redundancy and maximal relevance (mRMR) algorithm is utilized to select the most prominent features. To verify the effectiveness of the proposed method, a titanium alloy milling experiment was carried out and samples with different tool wear states were collected to build the proposed heterogeneous ensemble learning classifier. Moreover, the homogeneous ensemble learning model and majority voting strategy are also adopted to make a comparison. The analysis and comparison results show that the proposed heterogeneous ensemble learning classifier performs better in both classification accuracy and stability.

  13. Study of CO2 cyclic absorption stability of CaO-based sorbents derived from lime mud purified by sucrose method.

    Science.gov (United States)

    Ma, AiHua; Jia, QingMing; Su, HongYing; Zhi, YunFei; Tian, Na; Wu, Jing; Shan, ShaoYun

    2016-02-01

    Using lime mud (LM) purified by sucrose method, derived from paper-making industry, as calcium precursor, and using mineral rejects-bauxite-tailings (BTs) from aluminum production as dopant, the CaO-based sorbents for high-temperature CO2 capture were prepared. Effects of BTs content, precalcining time, and temperature on CO2 cyclic absorption stability were illustrated. The cyclic carbonation behavior was investigated in a thermogravimetric analyzer (TGA). Phase composition and morphologies were analyzed by XRD and SEM. The results reflected that the as-synthesized CaO-based sorbent doped with 10 wt% BTs showed a superior CO2 cyclic absorption-desorption conversion during multiple cycles, with conversion being >38 % after 50 cycles. Occurrence of Ca12Al14O33 phase during precalcination was probably responsible for the excellent CO2 cyclic stability.

  14. Repulsive and Restoring Casimir Forces Based on Magneto-Optical Effect

    Institute of Scientific and Technical Information of China (English)

    ZENG Ran; YANG Ya-Ping

    2011-01-01

    The Casimir force direction tuned by the external magnetic field due to the magneto-optical Voigt effect is investigated. The magneto-optical effect gives rise to the modified frequency-dependent electric permittivity and thus the electromagnetic properties of the materials can be adjusted to satisfy the condition of the formation of repulsive Casimir force. It is found that between the ordinary dielectric slab and magneto-optical material slab, a repulsive force may exist by adjusting the applied magnetic field. The restoring Casimir force can also be obtained if suitable parameter values are taken. For realistic materials, the repulsive and the restoring force is shown to possibly take place at typical distances in microelectromechanical systems.%@@ The Casimir force direction tuned by the external magnetic field due to the magneto-optical Voigt effect is investigated.The magneto-optical effect gives rise to the modified frequency-dependent electric permittivity and thus the electromagnetic properties of the materials can be adjusted to satisfy the condition of the formation of repulsive Casimir force.It is found that between the ordinary dielectric slab and magneto-optical material slab,a repulsive force may exist by adjusting the applied magnetic field.The restoring Casimir force can also be obtained if suitable parameter values are taken.For realistic materials,the repulsive and the restoring force is shown to possibly take place at typical distances in microelectromechanical systems.

  15. Experimental Research of Force Feedback Dataglove Based on Pneumatic Artificial Muscle

    Institute of Scientific and Technical Information of China (English)

    SUN Zhongsheng; BAO Gang; LI Xiaoning

    2009-01-01

    Force feedback dataglove is an important interface of human-machine interaction between manipulator and virtual assembly system, which is in charge of the bidirectional transmission of movement and force information between computer and operator. The exoskeleton force feedback dataglove is designed taking the pneumatic artificial muscle as actuator, meanwhile, its structure and work principle are introduced, and the force control problem is analyzed and researched by experiment. The mathematic model of grasping rigid object for finger is established. Considering the friction of tendon-sheath system and finger deformation, the closed-loop force control for a single joint, a single finger and multi-fingers are studied respectively by the feedforward proportional-integral(PI) control method with variable arguments. On the premise of the force smoothness, the control error of the force exerted on the finger joint is in the range of ±0.25 N, which meets the requirement of force feedback. By experimental analysis, the reason of force fluctuation is that the finger joint has a small amplitude quiver, and the consistent change tendency of the force between proximal interphalangeal(PIP) joint and distal interphalangeal(DIP) joint results from their angle coupling relationship.

  16. Development of sintering-resistant CaO-based sorbent derived from eggshells and bauxite tailings for cyclic CO2 capture.

    Science.gov (United States)

    Shan, ShaoYun; Ma, AiHua; Hu, YiCheng; Jia, QingMing; Wang, YaMing; Peng, JinHui

    2016-01-01

    Carbon dioxide, one of the major greenhouse gases, are believed to be a major contributor to global warming. As a consequence, it is imperative for us to control and remove CO2 emissions. The CaO, a kind of effective CO2 sorbent at high temperature, has attracted increasing attention due to some potential advantages. The main drawback in practical application is the deterioration of CO2 capture capacity following multiples cycles. In the present study, novel low-cost porous CaO-based sorbents with excellent CO2 absorption-desorption performance were synthesized using bauxite tailings (BTs) and eggshells as raw materials via solid-phase method. Effect of different BTs content on CO2 absorption-desorption properties was investigated. Phase composition and morphologies were analyzed by XRD and SEM, and CO2 absorption properties were investigated by the simultaneous thermogravimetric analyzer. The as-prepared CaO-based sorbent doped with 10 wt% BTs showed superior CO2 absorption stability during multiple absorption-desorption cycles, with being >55% conversion after 40 cycles. This improved CO2 absorption performance was attributed to the particular morphologies of the CaO-based sorbents. Additionally, during absorption-desorption cycles the occurrence of Ca12Al14O33 phase is considered to be responsible for the excellent CO2 absorption performance of CaO-based sorbents. In the meanwhile, the use of solid waste eggshell and BTs not only decreases the release of solid waste, but also moderates the greenhouse effect resulted from CO2.

  17. NaCl、NaCl—CaCl2、CaCl2盐水作基液对压井液性能影响的实验研究%Experiment and Study of the Influence of Base Fluid on Killing Fluid by Respectively Using Nacl,Nacl-CaCl2 or CaCl2 Bring as the Base Fluid

    Institute of Scientific and Technical Information of China (English)

    景岷雪

    2000-01-01

    为了保护储层,在修井、试井等作业中,普遍采用清洁盐水作压井液。文章通过进行浓度比较、聚合物盐析、岩块浸泡、有机质析出、乳化及动态流动模拟等一系列实验,从储层保护技术的角度,研究分析了NaCl、NaCl—CaCl2、CaCl2盐水作压井液基液,对所配制的压井液性能的影响。认为选择NaCl与CaCl2的混合液作为压井液基液,比用单纯的NaCl、CaCl2盐水作压井液基液具有可减少用盐量、降低矿化度、抑制大盐晶体形成、相对减少沥青质析出、且在岩石表面形成的高分子覆盖膜较薄、与原油乳化程度较低等优点,对配制有利于保护储层的压井液更为合宜。文章同时也提供了研制和评价保护储层优质压井液的实验研究方法。

  18. A diffraction correction for storage and loss moduli imaging using radiation force based elastography

    Science.gov (United States)

    Budelli, Eliana; Brum, Javier; Bernal, Miguel; Deffieux, Thomas; Tanter, Mickaël; Lema, Patricia; Negreira, Carlos; Gennisson, Jean-Luc

    2017-01-01

    Noninvasive evaluation of the rheological behavior of soft tissues may provide an important diagnosis tool. Nowadays, available commercial ultrasound systems only provide shear elasticity estimation by shear wave speed assessment under the hypothesis of a purely elastic model. However, to fully characterize the rheological behavior of tissues, given by its storage (G‧) and loss (G″) moduli, it is necessary to estimate both: shear wave speed and shear wave attenuation. Most elastography techniques use the acoustic radiation force to generate shear waves. For this type of source the shear waves are not plane and a diffraction correction is needed to properly estimate the shear wave attenuation. The use of a cylindrical wave approximation to evaluate diffraction has been proposed by other authors before. Here the validity of such approximation is numerically and experimentally revisited. Then, it is used to generate images of G‧ and G″ in heterogeneous viscoelastic mediums. A simulation algorithm based on the anisotropic and viscoelastic Green’s function was used to establish the validity of the cylindrical approximation. Moreover, two experiments were carried out: a transient elastography experiment where plane shear waves were generated using a vibrating plate and a SSI experiment that uses the acoustic radiation force to generate shear waves. For both experiments the shear wave propagation was followed with an ultrafast ultrasound scanner. Then, the shear wave velocity and shear wave attenuation were recovered from the phase and amplitude decay versus distance respectively. In the SSI experiment the cylindrical approximation was applied to correct attenuation due to diffraction effects. The numerical and experimental results validate the use of a cylindrical correction to assess shear wave attenuation. Finally, by applying the cylindrical correction G‧ and G″ images were generated in heterogeneous phantoms and a preliminary in vivo feasibility study

  19. A comparison of innovative air pollution control technology demonstrations at McClellan Air Force Base

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, T.E. [BDM Federal, McClellan AFB, CA (United States); Mook, P.H. Jr.; Wong, K.B. [SM-ALC/EMR, McClellan AFB, CA (United States)

    1997-12-31

    McClellan Air Force Base (AFB), located near Sacramento, California, is one of the Strategic Environmental Research and Development Program`s National Environmental Technology Test Sites. As part of the on-going environmental clean-up of McClellan AFB, the US Air Force has evaluated several innovative and conventional technologies for the treatment of vapor phase volatile organic compounds (VOCs). This paper presents an overview and comparison of the cost and performance of seven innovative technologies tested at McClellan AFB. McClellan AFB has found conventional off-gas treatment technologies to be effective but costly. Operation and maintenance (O and M) costs for treatment systems are increasingly becoming a major component of the environmental clean-up budget. The cost and performance of photolytic destruction, titanium dioxide photocatalytic oxidation, advanced polymer absorption media, flameless thermal oxidation, non-thermal plasma destruction, electron-beam destruction, and an advanced regenerative adsorption system are presented. Destruction removal efficiencies for VOCs have ranged from greater than 99.9 percent for flameless thermal oxidation to zero for the advanced polymer absorption media. Like the conventional technologies in use, all of the innovative technologies tested have been shown to be effective for treating a wide range of vapor phase contaminants, but each is only cost effective over limited range of off-gas concentrations. Some of the innovative technologies evaluated were found not to be useful over a wide range of contaminants or too costly to operate at their current stage of development. For example, titanium dioxide photocatalytic oxidation cannot effectively treat chlorinated VOCs in off-gas streams that contain moderate amounts of long-chain hydrocarbons.

  20. Vandenberg Air Force Base integrated resource assessment. Volume 3, Resource assessment

    Energy Technology Data Exchange (ETDEWEB)

    Daellenbach, K.K.; Dagle, J.E.; Dittmer, A.L.; Elliott, D.B.; Halverson, M.A.; Hickman, B.J.; Parker, G.B.; Richman, E.E.; Shankle, S.A.

    1993-06-01

    The US Air Force Space Command (SPACECOM) has tasked the Pacific Northwest Laboratory (PNL), as the lead laboratory supporting the US Department of Energy (DOE) Federal Energy Management Program (FEMP), to identify, evaluate, and assist in acquiring all cost-effective energy projects at Vandenberg Air Force Base (VAFB). This is part of a model program that PNL is designing to support energy-use decisions in the federal sector. This report provides the results of the fossil fuel and electric energy resource opportunity (ERO) assessments performed by PNL at the SPACECOM VAFB facility located approximately 50 miles northwest of Santa Barbara, California. It is a companion report to Volume 1, Executive Summary, and Volume 2, Baseline Detail. The results of the analysis of EROs are presented in ten common energy end-use categories (e.g., boilers and furnaces, service hot water, and building lighting). In addition, a case study of process loads at Space Launch Complex-4 (SLC-4) is included. A narrative description of each ERO is provided, including information on the installed cost, energy and dollar savings; impacts on operation and maintenance (O and M); and, when applicable, a discussion of energy supply and demand, energy security, and environmental issues. A description of the evaluation methodologies and technical and cost assumptions is also provided for each ERO. Summary tables present the cost-effectiveness of energy end-use equipment before and after the implementation of each ERO and present the results of the life-cycle cost (LCC) analysis indicating the net present value (NPV) and value index (VI) of each ERO. Finally, an appendix includes a summary of an economic analysis case study of the South Vandenberg Power Plant (SVPP) operating scenarios.