WorldWideScience

Sample records for stabilizing forces assessed

  1. Impediment in upper airway stabilizing forces assessed by phrenic nerve stimulation in sleep apnea patients

    Directory of Open Access Journals (Sweden)

    Vérin E

    2005-09-01

    Full Text Available Abstract Background The forces developed during inspiration play a key role in determining upper airway stability and the occurrence of nocturnal breathing disorders. Phrenic nerve stimulation applied during wakefulness is a unique tool to assess Upper airway dynamic properties and to measure the overall mechanical effects of the inspiratory process on UA stability. Objectives To compare the flow/pressure responses to inspiratory and expiratory twitches between sleep apnea subjects and normal subjects. Methods Inspiratory and expiratory twitches using magnetic nerve stimulation completed in eleven untreated sleep apnea subjects and ten normal subjects. Results In both groups, higher flow and pressure were reached during inspiratory twitches. The two groups showed no differences in expiratory twitch parameters. During inspiration, the pressure at which flow-limitation occurred was more negative in normals than in apneic subjects, but not reaching significance (p = 0.07. The relationship between pharyngeal pressure and flow adequately fitted with a polynomial regression model providing a measurement of upper airway critical pressure during twitch. This pressure significantly decreased in normals from expiratory to inspiratory twitches (-11.1 ± 1.6 and -15.7 ± 1.0 cm H2O respectively, 95% CI 1.6–7.6, p Conclusion Inspiratory-related upper airway dilating forces are impeded in sleep apnea patients.

  2. Stability of alert survivable forces during reductions

    Energy Technology Data Exchange (ETDEWEB)

    Canavan, G.H.

    1998-01-01

    The stability of current and projected strategic forces are discussed within a framework that contains elements of current US and Russian analyses. For current force levels and high alert, stability levels are high, as are the levels of potential strikes, due to the large forces deployed. As force levels drop towards those of current value target sets, the analysis becomes linear, concern shifts from stability to reconstitution, and survivable forces drop out. Adverse marginal costs generally provide disincentives for the reduction of vulnerable weapons, but the exchange of vulnerable for survivable weapons could reduce cost while increasing stability even for aggressive participants. Exchanges between effective vulnerable and survivable missile forces are studied with an aggregated, probabilistic model, which optimizes each sides` first and determines each sides` second strikes and costs by minimizing first strike costs.

  3. Stability diagram for the forced Kuramoto model.

    Science.gov (United States)

    Childs, Lauren M; Strogatz, Steven H

    2008-12-01

    We analyze the periodically forced Kuramoto model. This system consists of an infinite population of phase oscillators with random intrinsic frequencies, global sinusoidal coupling, and external sinusoidal forcing. It represents an idealization of many phenomena in physics, chemistry, and biology in which mutual synchronization competes with forced synchronization. In other words, the oscillators in the population try to synchronize with one another while also trying to lock onto an external drive. Previous work on the forced Kuramoto model uncovered two main types of attractors, called forced entrainment and mutual entrainment, but the details of the bifurcations between them were unclear. Here we present a complete bifurcation analysis of the model for a special case in which the infinite-dimensional dynamics collapse to a two-dimensional system. Exact results are obtained for the locations of Hopf, saddle-node, and Takens-Bogdanov bifurcations. The resulting stability diagram bears a striking resemblance to that for the weakly nonlinear forced van der Pol oscillator.

  4. Imaging stability in force-feedback high-speed atomic force microscopy

    International Nuclear Information System (INIS)

    Kim, Byung I.; Boehm, Ryan D.

    2013-01-01

    We studied the stability of force-feedback high-speed atomic force microscopy (HSAFM) by imaging soft, hard, and biological sample surfaces at various applied forces. The HSAFM images showed sudden topographic variations of streaky fringes with a negative applied force when collected on a soft hydrocarbon film grown on a grating sample, whereas they showed stable topographic features with positive applied forces. The instability of HSAFM images with the negative applied force was explained by the transition between contact and noncontact regimes in the force–distance curve. When the grating surface was cleaned, and thus hydrophilic by removing the hydrocarbon film, enhanced imaging stability was observed at both positive and negative applied forces. The higher adhesive interaction between the tip and the surface explains the improved imaging stability. The effects of imaging rate on the imaging stability were tested on an even softer adhesive Escherichia coli biofilm deposited onto the grating structure. The biofilm and planktonic cell structures in HSAFM images were reproducible within the force deviation less than ∼0.5 nN at the imaging rate up to 0.2 s per frame, suggesting that the force-feedback HSAFM was stable for various imaging speeds in imaging softer adhesive biological samples. - Highlights: ► We investigated the imaging stability of force-feedback HSAFM. ► Stable–unstable imaging transitions rely on applied force and sample hydrophilicity. ► The stable–unstable transitions are found to be independent of imaging rate

  5. Morocco; Financial System Stability Assessment

    OpenAIRE

    International Monetary Fund

    2003-01-01

    The Financial System Stability Assessment of Morocco reviews the reform program that is aimed at establishing a modern, market-oriented financial system that optimizes the mobilization of savings and the allocation of financial resources. It reviews the modernization of the banking sector and the development of competition within the sector, development of financial markets, and removal of constraints on financial system activity. It also provides reports on the Observance of Standards and Co...

  6. Nigeria; Financial Sector Stability Assessment

    OpenAIRE

    International Monetary Fund

    2013-01-01

    This Financial Sector Stability Assessment on Nigeria discusses the macroeconomic performance and structure of the financial system. Although Nigerian economy experienced both domestic and external shocks in recent years, the economy continued to grow rapidly, achieving more than 7 percent growth each year since 2009. The performance of financial institutions has begun to improve, though some of the emergency anti-crisis measures continue to be in place. However, the regulatory and supervisor...

  7. Canada; Financial Sector Stability Assessment

    OpenAIRE

    International Monetary Fund

    2014-01-01

    This report discusses key findings of the Financial Sector Stability Assessment on Canada. Canada’s financial system successfully navigated the global financial crisis, and stress tests suggest that major financial institutions would continue to be resilient to credit, liquidity, and contagion risks arising from a severe stress scenario. Elevated housing prices and high household debt remain an area of concern, though targeted prudential and macroprudential measures are proving to be effectiv...

  8. Does dynamic stability govern propulsive force generation in human walking?

    Science.gov (United States)

    Browne, Michael G; Franz, Jason R

    2017-11-01

    Before succumbing to slower speeds, older adults may walk with a diminished push-off to prioritize stability over mobility. However, direct evidence for trade-offs between push-off intensity and balance control in human walking, independent of changes in speed, has remained elusive. As a critical first step, we conducted two experiments to investigate: (i) the independent effects of walking speed and propulsive force ( F P ) generation on dynamic stability in young adults, and (ii) the extent to which young adults prioritize dynamic stability in selecting their preferred combination of walking speed and F P generation. Subjects walked on a force-measuring treadmill across a range of speeds as well as at constant speeds while modulating their F P according to a visual biofeedback paradigm based on real-time force measurements. In contrast to improvements when walking slower, walking with a diminished push-off worsened dynamic stability by up to 32%. Rather, we find that young adults adopt an F P at their preferred walking speed that maximizes dynamic stability. One implication of these findings is that the onset of a diminished push-off in old age may independently contribute to poorer balance control and precipitate slower walking speeds.

  9. Transient stability index for online stability assessment and contingency evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Ribbens-Pavella, M; Murthy, P G; Horward, J L; Carpentier, J L

    1982-04-01

    An on-line methodology is proposed for assessing the robustness of a power system from the point of view of transient stability, and a scalar expression, the transient stability index, is accordingly derived. The reliability and sensitivity of this index are tested by means of simulations for a number of power system cases. The index is shown to be appropriate for online stability assessment, contingency evaluation and preventive control. 14 refs.

  10. Stability of elastic columns with periodic retarded follower forces

    Science.gov (United States)

    Ma, Haitao; Butcher, Eric A.

    2005-09-01

    The objective of this work is to present a stability analysis for elastic columns under the influence of periodically varying follower forces whose orientation is retarded, i.e., depends on the position of the system at a previous time. One- and two-degree-of-freedom (dof) discretized systems under the simultaneous influence of both parametric excitation and time-delay, whose effects on such systems have previously been only considered separately, are studied. By employing an orthogonal polynomial approximation, the infinite-dimensional Floquet transition matrix associated with the time-periodic differential-delay system is approximated. The stability criteria that all the eigenvalues (Floquet multipliers) of this matrix must lie within the unit circle is then applied. The stability charts for different combinations of the remaining system parameters are shown, and the previously reported results for the special cases where either the parametric excitation or the time-delay vanishes are verified. Two cases, when the parametric forcing period is equal to or twice the delay period are taken into consideration in this work. For special cases of the single dof system, the numerical stability plots are verified by considering the analytical expressions for the corresponding stability boundaries for an analogous delayed Mathieu equation.

  11. Application of Enlisted Force Retention Levels and Career Field Stability

    Science.gov (United States)

    2017-03-23

    APPLICATION OF ENLISTED FORCE RETENTION LEVELS AND CAREER FIELD STABILITY THESIS Presented to the Faculty Department of Operational Sciences ...Fulfillment of the Requirements for the Degree of Master of Science in Operations Research Jamie T. Zimmermann, MS, BS Captain, USAF March 2017...Appendix B. The function proc lifetest is a nonparametric estimate of the survivor function using either the Kaplan-Meier method or the actuarial

  12. Test Bench Development for Femur Stability Assessment

    Directory of Open Access Journals (Sweden)

    Samuel SANCHEZ-CABALLERO

    2015-01-01

    Full Text Available This paper shows the design and development of a test bench for humanfemurs. The main uses of this test bench will run from artificial femurs comparisonwith real femurs, to join stability assessment after bone a fracture repair. Amongthis uses is specially designed for condylar fractures testing. The test bench isdeveloped from a self-made existing tensile/compression testing machine. Thedesign procedure is supported by a literature review about the bone mechanicalbehavior and composition generally and the knee joint performance and repairparticularly. On the basis of this review, the machine was designed to simulate theadduction and abduction movements of the joint. The magnitudes to be measuredare: the compression force, the bone displacement (vertical and the knee jointrotation

  13. Normal and friction stabilization techniques for interactive rigid body constraint-based contact force computations

    DEFF Research Database (Denmark)

    Silcowitz-Hansen, Morten; Abel, Sarah Maria Niebe; Erleben, Kenny

    2010-01-01

    We present a novel, yet simple, method for stabilization of normal forces. A normal stabilization term, carefully designed from hypotheses about interactive usability, is added to the contact force problem. Further, we propose friction stabilization as a completely new stabilization paradigm...

  14. Task force report on health effects assessment

    International Nuclear Information System (INIS)

    Anderson, C.; Hushon, J.

    1978-08-01

    From April to August, 1978 MITRE supported the Health Effects Assessment Task Force sponsored by the Office of the Assistant Secretary for the Environment at DOE. The findings of that Task Force are incorporated in this report and include a detailed definition of health effects assessment, a survey of the mandates for health effects assessments within DOE/EV, a review of current DOE-EV health effects assessment activities, an analysis of the constraints affecting the health effects assessment process and a discussion of the Task Force recommendations. Included as appendices are summaries of two workshops conducted by the Task Force to determine the state-of-the-art of health effects assessment and modeling and a review of risk assessment activities in other federal agencies. The primary recommendation of the panel was that an office be designated or created under the Office of the Assistant Secretary for the Environment to coordinate the Health Effects Risk Assessment effort covering up to 40 program and policy areas; a similar need was expressed for the environmental effects assessment area. 1 tab

  15. Assessing Locally Focused Stability Operations

    Science.gov (United States)

    2014-01-01

    interest to other organizations within the Army, as well as to organizations within the Air Force, the Navy, the Marines, and the Intelligence Community...activities that lead to progress in the short term from a military standpoint (e.g., rewarding intelligence sources with food) may be at odds with...the aims and objectives of an aid organization working in the same area (e.g., preventing malnutrition for all), and both may impede the long-term

  16. Argonne program to assess superconducting stability

    International Nuclear Information System (INIS)

    Wang, S.T.; Turner, L.R.; Huang, Y.C.; Dawson, J.W.; Harrang, J.; Hilal, M.A.; Lieberg, M.; Gonczy, J.D.; Kim, S.H.

    1978-01-01

    To assess superconductor stability, a complete program is developed to obtain basic information on the effects of local mechanical perturbations on the cryostatic stability. An analytical model for computing the transient recovery following the mechanical perturbation is developed. A test program is undertaken to develop data needed to verify the conclusions reached through the analytical studies

  17. Assessing the industry using Porter's five forces.

    Science.gov (United States)

    2014-01-01

    To develop a business and plan for the future, there is a need to assess the current situation. One way of doing this is to use Porter's five forces framework. This was the brainchild of Harvard Business School's Michael Porter and developed in 1979. Looking at the competitive intensity of an industry, the model assesses internal and external factors that act together to determine the direction of the business; taken together, this gives an indication of the attractiveness of the industry.

  18. Malaysia; Financial Sector Stability Assessment

    OpenAIRE

    International Monetary Fund

    2013-01-01

    This assessment is a review of the financial environment of Malaysia. Like many other Asian countries, Malaysia experienced financial distress in the late 1990s, but the country’s policy reforms have moved it to a successful economy. A ten-year financial plan (2001–10) by Bank Negara Malaysia restructured the financial sector. Banks were well capitalized, household debts were strengthened, and securities and insurances were developed. Malaysia thus became the global center for Islamic finance...

  19. Spain; Financial System Stability Assessment

    OpenAIRE

    International Monetary Fund

    2012-01-01

    This report summarizes the findings of the Financial Sector Assessment Program (FSAP) Update for Spain. Although there is a core of strong banks that are well managed and appear resilient to further shocks, vulnerabilities remain. Substantial progress has been made in reforming the former savings banks, and the most vulnerable institutions have either been resolved or are being restructured. Recent measures address the most problematic part of banks’ portfolios. Moving ahead, a further restru...

  20. Automated Assessment of Postural Stability (AAPS)

    Science.gov (United States)

    2016-10-01

    performed a battery of standard clinical tests of dynamic posture, whereas the fourth subject performed the stereotyped postures (e.g. movements restricted...Processing & Control [2] Napoli A, Ward C, Glass S, Tucker C, Obeid I (2016) “Automated Assessment of Postural Stability System,” IEEE Engineering in

  1. Morocco; Financial System Stability Assessment: Update

    OpenAIRE

    International Monetary Fund

    2008-01-01

    This paper presents an update to the Financial System Stability Assessment on Morocco. Major reforms have been achieved since the 2002 Financial Sector Assessment Program (FSAP) within a policy of actively promoting economic and financial sector opening. The 2002 FSAP recommendations have been largely implemented. Although the financial system is stable and considerably more robust than in the past, the liberalization of capital flows and increased exchange rate flexibility present challenges...

  2. Body-force-driven multiplicity and stability of combined free and forced convection in rotating curved ducts: Coriolis force

    Science.gov (United States)

    Yang, T.; Wang, L.

    A numerical study is made on the fully developed bifurcation structure and stability of forced convection in a rotating curved duct of square cross-section. Solution structure is determined as variation of a parameter that indicates the effect of rotation (Coriolis-force-driven multiplicity). Three solutions for the flows in a stationary curved duct obtained in the work of Yang and Wang [1] are used as initial solutions of continuation calculations to unfold the solution branches. Twenty-one solution branches are found comparing with five obtained by Selmi and Nandakumar [2]. Dynamic responses of the multiple solutions to finite random disturbances are examined by the direct transient computation. Results show that characteristics of physically realizable fully developed flows changes significantly with variation of effect of rotation. Fourteen sub-ranges are identified according to characteristics of physically realizable solutions. As rotation effect changes, possible physically realizable fully-developed flows can be stable steady 2-cell state, stable multi-cell state, temporal periodic oscillation between symmetric/asymmetric 2-cell/4-cell flows, temporal oscillation with intermittency, temporal chaotic oscillation and temporal oscillation with pseudo intermittency. Among these possible physically realizable fully developed flows, stable multi-cell state and stable steady 2-cell state exist as dual stable. And oscillation with pseudo intermittency is a new phenomenon. In addition to the temporal oscillation with intermittency, sudden shift from stationary stable solution to temporal chaotic oscillation is identified to be another way of onset of chaos.

  3. Practical considerations in voltage stability assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kundur, P; Gao, B [Powertech Labs. Inc., Surrey, BC (Canada)

    1994-12-31

    This paper deals with some of the most important practical issues related to voltage stability assessment of large practical systems. A brief discussion of the practical aspects of voltage stability problem and prevention of voltage instability is given first, followed by descriptions of different analytical techniques and tools for voltage stability analysis. Presentations of analytical tools is focused on the VSTAB program which incorporates the modal analysis, continuation power flow, and shortest distance to instability techniques, Finally, an example case study of a practical large system is presented. The case study illustrates how modal analysis is used to determine the most effective load shedding scheme for preventing voltage instability. (author) 15 refs., 2 figs., 2 tabs.

  4. Force-free thin flux tubes: Basic equations and stability

    International Nuclear Information System (INIS)

    Zhugzhda, Y.D.

    1996-01-01

    The thin flux tube approximation is considered for a straight, symmetrical, force-free, rigidly rotating flux tube. The derived set of equations describes tube, body sausage, and Alfveacute charn wave modes and is valid for any values of Β. The linear waves and instabilities of force-free flux tubes are considered. The comparison of approximate and exact solutions for an untwisted, nonrotating flux tube is performed. It is shown that the approximate and exact dispersion equations coincides, except the 20% discrepancy of sausage frequencies. An effective cross section is proposed to introduce the removal of this discrepancy. It makes the derived approximation correct for the force-free thin flux tube dynamics, except the detailed structure of radial eigenfunction. The dispersion of Alfveacute charn torsional waves in a force-free tubes appears. The valve effect of one directional propagation of waves in rotating twisted tube is revealed. The current and rotational sausage instabilities of a force-free, thin flux tube are considered. copyright 1996 American Institute of Physics

  5. Artificial Intelligence Software for Assessing Postural Stability

    Science.gov (United States)

    Lieberman, Erez; Forth, Katharine; Paloski, William

    2013-01-01

    A software package reads and analyzes pressure distributions from sensors mounted under a person's feet. Pressure data from sensors mounted in shoes, or in a platform, can be used to provide a description of postural stability (assessing competence to deficiency) and enables the determination of the person's present activity (running, walking, squatting, falling). This package has three parts: a preprocessing algorithm for reading input from pressure sensors; a Hidden Markov Model (HMM), which is used to determine the person's present activity and level of sensing-motor competence; and a suite of graphical algorithms, which allows visual representation of the person's activity and vestibular function over time.

  6. Stabilization Operations Through Military Capacity Building-Integration Between Danish Conventional Forces and Special Operations Forces

    Science.gov (United States)

    2016-12-01

    INTENTIONALLY LEFT BLANK v ABSTRACT Due to instability in Africa and the Middle East, Denmark’s political commitment to deploy troops to stabilize ...Denmark’s political commitment to deploy troops to stabilize fragile regions is not expected to decrease in the near future. The political ambition for...fragile regions is not expected to decrease in the near future. The political ambition for Denmark is to conduct stabilization efforts through

  7. Elbow joint stability in relation to forced external rotation

    DEFF Research Database (Denmark)

    Deutch, S.R.; Jensen, S.L.; Olsen, B.S.

    2003-01-01

    The objective of this study was to evaluate the osseous constraint related to forced forearm external rotation as the initial stage in a posterior elbow dislocation. Six joint specimens without soft tissues were examined in a joint analysis system developed for simulation of dislocation. The osse......The objective of this study was to evaluate the osseous constraint related to forced forearm external rotation as the initial stage in a posterior elbow dislocation. Six joint specimens without soft tissues were examined in a joint analysis system developed for simulation of dislocation...... external forearm rotation until the point of maximal torque decreased from a maximum in full extension to a minimum at 30 degrees of elbow flexion (P =.03). The elbow in a slightly flexed position, varus stress, and forearm external rotation trauma might be the important biomechanical factors...

  8. Assessing Leadership Potential for the Army's Future Force

    National Research Council Canada - National Science Library

    Donahue, Scott

    2004-01-01

    A transforming Army requires a corresponding transformation in its leader development and assessment methodology to enable the future force in the volatile uncertain complex and ambiguous contemporary...

  9. Stability assessment for underground excavations and key construction techniques

    CERN Document Server

    Zhu, Hanhua; Zhao, Yu; Niu, Fusheng

    2017-01-01

    This book examines how the state of underground structures can be determined with the assistance of force, deformation and energy. It then analyzes mechanized shield methods, the New Austrian tunneling method (NATM) and conventional methods from this new perspective. The book gathers a wealth of cases reflecting the experiences of practitioners and administrators alike. Based on statistical and engineering studies of these cases, as well as lab and field experiments, it develops a stability assessment approach incorporating a stable equilibrium, which enables engineers to keep the structure and surrounding rocks safe as long as the stable equilibrium and deformation compliance are maintained. The book illustrates the implementation of the method in various tunneling contexts, including soil-rock mixed strata, tunneling beneath operating roads, underwater tunnels, and tunnel pit excavation. It offers a valuable guide for researchers, designers and engineers, especially those who are seeking to understand the u...

  10. Static and dynamic stability of the guidance force in a side-suspended HTS maglev system

    Science.gov (United States)

    Zhou, Dajin; Cui, Chenyu; Zhao, Lifeng; Zhang, Yong; Wang, Xiqing; Zhao, Yong

    2017-02-01

    The static and dynamic stability of the guidance force in a side-suspended HTS-PMG (permanent magnetic guideway) system were studied theoretically and experimentally. It is found that there are two types of guidance force that exist in the HTS-PMG system, which are sensitive to the levitation gap and the arrangement of YBCO bulks around the central axis of the PMG. An optimized YBCO array was used to stabilize the system, which enabled a side-suspended HTS-PMG maglev vehicle to run stably at 102 km h-1 on a circular test track with 6.5 m in diameter.

  11. Mutually opposing forces during locomotion can eliminate the tradeoff between maneuverability and stability

    Science.gov (United States)

    Cowan, Noah; Sefati, Shahin; Neveln, Izaak; Roth, Eatai; Mitchell, Terence; Snyder, James; Maciver, Malcolm; Fortune, Eric

    A surprising feature of animal locomotion is that organisms typically produce substantial forces in directions other than what is necessary to move the animal through its environment, such as perpendicular to, or counter to, the direction of travel. The effect of these forces has been difficult to observe because they are often mutually opposing and therefore cancel out. Using a combination of robotic physical modeling, computational modeling, and biological experiments, we discovered that these forces serve an important role: to simplify and enhance the control of locomotion. Specifically, we examined a well-suited model system, the glass knifefish Eigenmannia virescens, which produces mutually opposing forces during a hovering behavior. By systematically varying the locomotor parameters of our biomimetic robot, and measuring the resulting forces and kinematics, we demonstrated that the production and differential control of mutually opposing forces is a strategy that generates passive stabilization while simultaneously enhancing maneuverability. Mutually opposing forces during locomotion are widespread across animal taxa, and these results indicate that such forces can eliminate the tradeoff between stability and maneuverability, thereby simplifying robotic and neural control.

  12. Assessment of trace element stabilization in soil

    OpenAIRE

    Kumpiene, Jurate

    2005-01-01

    The thesis deals with the remediation of trace element contaminated soil by the chemical stabilization technique. The objective is to complement the knowledge about possibilities of applying the stabilization either (1) as an alternate soil remediation method to excavation and landfilling or (2) for a pre-treatment of contaminated soil before landfilling. The work is based on two case studies of the stabilization of 1) Cr, Cu, As, and Zn contaminated soil using metallic iron and 2) Pb and Cu ...

  13. TOTAL FORCE INTEGRATION: PROVIDING STABILITY FOR CITIZEN SOLDIERS IN AN EVER CHANGING AIR FORCE

    Science.gov (United States)

    2016-10-01

    specifically called for achieving a better work - life balance and “leveraging the best talents of our Guard, Reserve, and civilian teams.”88 Taking...paper will offer unique scenarios (Let it Be, Nowhere Man, The Long and Winding Road, and We Can Work It Out) which balance mission readiness against...entire Air Force airlift mission, resulting in substantial stressors on civilian careers and family life , which has always been the cornerstone of

  14. Multivariate stability of force-reflecting teleoperation: Structures of finite and infinite zeros

    International Nuclear Information System (INIS)

    Daniel, R.W.; McAree, P.R.

    2000-01-01

    This paper presents a stability analysis of force-position teleoperation under general end-effector contact. The analysis is based on the finite and infinite zero structure of the multivariable root-locus resulting from modulation of the environment stiffness. The starting point is an analysis of the stability of robot force control, motivated by the observation that the human-operator in a force reflection loop acts as a force servo, generating position commands in response to reflected force. Asymptotic root loci properties are used to establish passivity conditions on force feedback to give root locus interpretations of the well-known results that (1) feedback via the inverse joint Jacobian can lead to (kinematic) instability and that (2) passivity is preserved by kinematically proper force feedback through the transpose of the joint angle Jacobian. It is demonstrated that a fully constrained force-position teleoperation loop has an identical infinite zero structure to that of a slave manipulation under kinematically proper force control and that the dominant vibration modes of a force-position loop are fully described by a multivariable analogue of the single-input single-output pseudo-system investigated in a study by Daniel and McAree. Extension of the analysis to cover partial end-effector constraint provides a design tool for teleoperation control and serves to aid selection of teleoperation slate-arms. The paper concludes by giving a passivity condition for multiple-input multiple-output force-position teleoperation for stable contact against all environments

  15. Impaction Force Influences Taper-Trunnion Stability in Total Hip Arthroplasty.

    Science.gov (United States)

    Danoff, Jonathan R; Longaray, Jason; Rajaravivarma, Raga; Gopalakrishnan, Ananthkrishnan; Chen, Antonia F; Hozack, William J

    2018-01-31

    This study investigated the influence of femoral head impaction force, number of head strikes, the energy sequence of head strikes, and head offset on the strength of the taper-trunnion junction. Thirty titanium-alloy trunnions were mated with 36-mm zero-offset cobalt-chromium femoral heads of corresponding taper angle. A drop tower impacted the head with 2.5J or 8.25J, resulting in 6 kN or 14 kN impaction force, respectively, in a single strike or combinations of 6 kN + 14 kN or 14 kN + 14 kN. In addition, ten 36-mm heads with -5 and +5 offset were impacted with sequential 14 kN + 14 kN strikes. Heads were subsequently disassembled using a screw-driven mechanical testing frame, and peak distraction force was recorded. Femoral head pull-off force was 45% the strike force, and heads struck with a single 14 kN impact showed a pull-off force twice that of the 6 kN group. Two head strikes with the same force did not improve pull-off force for either 6 kN (P = .90) or 14 kN (P = .90). If the forces of the 2 impactions varied, but either impact measured 14 kN, a 51% higher pull-off force was found compared to impactions of either 6 kN or 6 kN + 6 kN. Femoral head offset did not significantly change the pull-off force among -5, 0, and +5 heads (P = .37). Femoral head impaction force influenced femoral head trunnion-taper stability, whereas offset did not affect pull-off force. Multiple head strikes did not add additional stability, as long as a single strike achieved 14 kN force at the mallet-head impactor interface. Insufficient impaction force may lead to inadequate engagement of the trunnion-taper junction. Copyright © 2018 Elsevier Inc. All rights reserved.

  16. Final Environmental Assessment Travis Air Force Base Burke Property Housing

    National Research Council Canada - National Science Library

    1999-01-01

    ... (40 CFR Parts 1500-1508) and Air Force Instruction 32-7061, the U.S. Air Force conducted an assessment of the potential environmental consequences of the construction of up to 281 military family housing units at Travis AFB...

  17. Effect of Electrodynamic Forces on the Attitude Stabilization of a Satellite in Ecliptic orbits

    Science.gov (United States)

    Abdel-Aziz, Yehia

    This work is based on the previous paper of the author [1]. The present paper is devoted to the investigation of the attitude dynamics of an ecliptic satellite moving in the magnetic field of the Earth. Eelectrodynamic forces result from the motion of a charged satelite relative to the magnetic field of the Earth. The torque due to electrodynamic effect of the Lorentz forces on the attitude stabilization of the satellite is studied with the detailed model of the Earth's magnetic field. A method for estimating the stable and unstable regions of the equilibrium positions based on Euler's equation is also discussed. The results show that Lorentz forces can affect the stablization of the satellite, in particular for highly eccentric orbits and also for large satellte. [1] Abdel-Aziz, Y. A. Attitude Stabilization of a Rigid Spacecraft in the Geomagnetic Field. AdSpR 40, 18-24, 2007.

  18. Stability of aerosol droplets in Bessel beam optical traps under constant and pulsed external forces

    International Nuclear Information System (INIS)

    David, Grégory; Esat, Kıvanç; Hartweg, Sebastian; Cremer, Johannes; Chasovskikh, Egor; Signorell, Ruth

    2015-01-01

    We report on the dynamics of aerosol droplets in optical traps under the influence of additional constant and pulsed external forces. Experimental results are compared with simulations of the three-dimensional droplet dynamics for two types of optical traps, the counter-propagating Bessel beam (CPBB) trap and the quadruple Bessel beam (QBB) trap. Under the influence of a constant gas flow (constant external force), the QBB trap is found to be more stable compared with the CPBB trap. By contrast, under pulsed laser excitation with laser pulse durations of nanoseconds (pulsed external force), the type of trap is of minor importance for the droplet stability. It typically needs pulsed laser forces that are several orders of magnitude higher than the optical forces to induce escape of the droplet from the trap. If the droplet strongly absorbs the pulsed laser light, these escape forces can be strongly reduced. The lower stability of absorbing droplets is a result of secondary thermal processes that cause droplet escape

  19. Stability of aerosol droplets in Bessel beam optical traps under constant and pulsed external forces

    Energy Technology Data Exchange (ETDEWEB)

    David, Grégory; Esat, Kıvanç; Hartweg, Sebastian; Cremer, Johannes; Chasovskikh, Egor; Signorell, Ruth, E-mail: rsignorell@ethz.ch [Laboratory of Physical Chemistry, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich (Switzerland)

    2015-04-21

    We report on the dynamics of aerosol droplets in optical traps under the influence of additional constant and pulsed external forces. Experimental results are compared with simulations of the three-dimensional droplet dynamics for two types of optical traps, the counter-propagating Bessel beam (CPBB) trap and the quadruple Bessel beam (QBB) trap. Under the influence of a constant gas flow (constant external force), the QBB trap is found to be more stable compared with the CPBB trap. By contrast, under pulsed laser excitation with laser pulse durations of nanoseconds (pulsed external force), the type of trap is of minor importance for the droplet stability. It typically needs pulsed laser forces that are several orders of magnitude higher than the optical forces to induce escape of the droplet from the trap. If the droplet strongly absorbs the pulsed laser light, these escape forces can be strongly reduced. The lower stability of absorbing droplets is a result of secondary thermal processes that cause droplet escape.

  20. Stability of aerosol droplets in Bessel beam optical traps under constant and pulsed external forces.

    Science.gov (United States)

    David, Grégory; Esat, Kıvanç; Hartweg, Sebastian; Cremer, Johannes; Chasovskikh, Egor; Signorell, Ruth

    2015-04-21

    We report on the dynamics of aerosol droplets in optical traps under the influence of additional constant and pulsed external forces. Experimental results are compared with simulations of the three-dimensional droplet dynamics for two types of optical traps, the counter-propagating Bessel beam (CPBB) trap and the quadruple Bessel beam (QBB) trap. Under the influence of a constant gas flow (constant external force), the QBB trap is found to be more stable compared with the CPBB trap. By contrast, under pulsed laser excitation with laser pulse durations of nanoseconds (pulsed external force), the type of trap is of minor importance for the droplet stability. It typically needs pulsed laser forces that are several orders of magnitude higher than the optical forces to induce escape of the droplet from the trap. If the droplet strongly absorbs the pulsed laser light, these escape forces can be strongly reduced. The lower stability of absorbing droplets is a result of secondary thermal processes that cause droplet escape.

  1. Stability of aerosol droplets in Bessel beam optical traps under constant and pulsed external forces

    Science.gov (United States)

    David, Grégory; Esat, Kıvanç; Hartweg, Sebastian; Cremer, Johannes; Chasovskikh, Egor; Signorell, Ruth

    2015-04-01

    We report on the dynamics of aerosol droplets in optical traps under the influence of additional constant and pulsed external forces. Experimental results are compared with simulations of the three-dimensional droplet dynamics for two types of optical traps, the counter-propagating Bessel beam (CPBB) trap and the quadruple Bessel beam (QBB) trap. Under the influence of a constant gas flow (constant external force), the QBB trap is found to be more stable compared with the CPBB trap. By contrast, under pulsed laser excitation with laser pulse durations of nanoseconds (pulsed external force), the type of trap is of minor importance for the droplet stability. It typically needs pulsed laser forces that are several orders of magnitude higher than the optical forces to induce escape of the droplet from the trap. If the droplet strongly absorbs the pulsed laser light, these escape forces can be strongly reduced. The lower stability of absorbing droplets is a result of secondary thermal processes that cause droplet escape.

  2. Double Trait Assessment Test Battery for Air Force Pilots

    National Research Council Canada - National Science Library

    Tarnowski, Adam

    1998-01-01

    Building on years of theoretical discussions as well as diagnostic experience in the Polish Air Force Institute of Aviation Medicine, a battery of psychological tests was proposed for the assessment...

  3. Simulation of VDE under intervention of vertical stability control and vertical electromagnetic force on the ITER vacuum vessel

    International Nuclear Information System (INIS)

    Miyamoto, S.; Sugihara, M.; Shinya, K.; Nakamura, Y.; Toshimitsu, S.; Lukash, V.E.; Khayrutdinov, R.R.; Sugie, T.; Kusama, Y.; Yoshino, R.

    2012-01-01

    Highlights: ► Taking account of intervention of VS control, VDE simulations were carried out. ► Malfunctioning of VS circuit (positive feedback) enhances the vertical force. ► The worst case was explored for vertical force on the ITER vacuum vessel. ► We confirmed the force is still within the design margin even if the worst case. - Abstract: Vertical displacement events (VDEs) and disruptions usually take place under intervention of vertical stability (VS) control and the vertical electromagnetic force induced on vacuum vessels is potentially influenced. This paper presents assessment of the force that arises from the VS control in ITER VDEs using a numerical simulation code DINA. The focus is on a possible malfunctioning of the ex-vessel VS control circuit: radial magnetic field is unintentionally applied to the direction of enhancing the vertical displacement further. Since this type of failure usually causes the largest forces (or halo currents) observed in the present experiments, this situation must be properly accommodated in the design of the ITER vacuum vessel. DINA analysis shows that although the ex-vessel VS control modifies radial field, it does not affect plasma motion and current quench behavior including halo current generation because the vacuum vessel shields the field created by the ex-vessel coils. Nevertheless, the VS control modifies the force on the vessel by directly acting on the eddy current carried by the conducting structures of the vessel. Although the worst case was explored in a range of plasma inductance and pattern of VS control in combination with the in-vessel VS control circuit, the result confirmed that the force is still within the design margin.

  4. General stability of memory-type thermoelastic Timoshenko beam acting on shear force

    Science.gov (United States)

    Apalara, Tijani A.

    2018-03-01

    In this paper, we consider a linear thermoelastic Timoshenko system with memory effects where the thermoelastic coupling is acting on shear force under Neumann-Dirichlet-Dirichlet boundary conditions. The same system with fully Dirichlet boundary conditions was considered by Messaoudi and Fareh (Nonlinear Anal TMA 74(18):6895-6906, 2011, Acta Math Sci 33(1):23-40, 2013), but they obtained a general stability result which depends on the speeds of wave propagation. In our case, we obtained a general stability result irrespective of the wave speeds of the system.

  5. ASSESSMENT OF GRIP FORCE CONTROL IN PATIENTS WITH MUSCULAR DYSTROPHY

    Directory of Open Access Journals (Sweden)

    Gregorij Kurillo

    2004-12-01

    Full Text Available Background. The majority of hand functionality tests are based on qualitative assessment which largely depends on the experience of the therapist. Computer-assisted methods can provide more objective and accurate measurements of the grip force and other parameters related to grasping.Methods. We analysed the grip force control in 12 patients with muscular dystrophy using the tracking system developed. The system consists of a grip-measuring device with endobjects assessing the force applied in different grips. The device was used as input to a tracking task where the patient applied the grip force according to the visual feedback from the computer screen. Each patient performed two tasks which consisted of tracking a ramp and sinus target.Results. We analysed the maximal grip force as assessed in the ramp task and the tracking accuracy of the sinus task. The results are compared among five different grips (cylindrical, lateral, palmar, pinch and spherical grip, applied with dominant and non-dominant hand. The results show no significant difference in tracking accuracy between the dominant and non-dominant hand.Conclusions. The results obtained in tracking the ramp target showed that the method could be used for the assessment of the muscle fatigue, providing quantitative information on muscle capacity. The results of the sinus-tracking task showed that the method can evaluate the grip force control in different types of grips, providing information on hand dexterity, muscle activation patterns or tremor.

  6. Assessment of stability characteristics of MFTF coils

    International Nuclear Information System (INIS)

    1979-03-01

    Certain aspects of the MFTF (Mirror Fusion Test Facility) conductor performance were investigated. Recovery analysis of the MFTF conductor was studied using GA's stability code. The maximum length of uncooled, unsoldered composite core which can recover from a thermal excursion was determined analytically. A maximum credible mechanical disturbance in terms of energy deposition, conductor motion and length, and time duration, was postulated. 5 references, 4 figures

  7. The Bahamas; Financial Sector Stability Assessment

    OpenAIRE

    International Monetary Fund

    2013-01-01

    This article is an overview of the structure of the Bahamian financial system. After the financial crisis in the United States, the Bahamian financial structure showed fragile growth. Tourism, the main source of income for the domestic economy, weakened owing to the U.S. crisis. The increase in oil prices was the key reason for the destroyed infrastructure. However, amidst the vulnerabilities, the banking sector showed stability with high capital and liquidity and sustained challenges; the in...

  8. Assessment of Nutrient Stability in Space Foods

    Science.gov (United States)

    Zwart, S. R.; Perchonok, M.; Braby, L. A.; Kloeris, V. A.; Smith, S. M.

    2009-01-01

    Maintaining an intact nutrient supply in the food system flown on spacecraft is a critical issue for mission success and crew health and safety. Early polar expeditions and exploration expeditions by sailing vessels have taught us that a deficiency, or excess, of even a single vitamin in the food supply can be catastrophic. Evidence from ground-based research indicates that some vitamins are destroyed and fatty acids are oxidized (and therefore rendered dangerous or useless) by different types of radiation and by conditions of long-term storage. We hypothesize that radiation and long-term storage in the space-flight environment will affect the stability of vitamins, amino acids, and fatty acids in the space food system. The research objectives of our ongoing stability studies are to determine the stability of water- and fat-soluble vitamins, fatty acids, and amino acids in the space food supply before and after space flight on the International Space Station (ISS). Foods were analyzed after 2 weeks (a flight control), 11, 19, and 28 months of flight. Along with the space-flown foods, ground-based controls matched for time, light, and temperature are analyzed. The flight studies complement planned ground-based studies of the effects of radiation on vitamins, amino acids, and fatty acids. Flight studies are needed because a model based on ground-based data cannot predict all of the effects of the space-flight environment. Flight studies provide a more accurate test system to determine the effects on these nutrients of the temperature, and radiation conditions in the space-flight environment. Ground studies are required to evaluate longer missions and higher radiation levels expected outside low-Earth orbit. In addition to providing information about nutrient stability in space, the results of these studies will help NASA determine if a need exists to develop special packaging that can ensure stability of foods and nutrients in space, or if further studies of nutrient

  9. Probing of miniPEGγ-PNA-DNA Hybrid Duplex Stability with AFM Force Spectroscopy.

    Science.gov (United States)

    Dutta, Samrat; Armitage, Bruce A; Lyubchenko, Yuri L

    2016-03-15

    Peptide nucleic acids (PNA) are synthetic polymers, the neutral peptide backbone of which provides elevated stability to PNA-PNA and PNA-DNA hybrid duplexes. It was demonstrated that incorporation of diethylene glycol (miniPEG) at the γ position of the peptide backbone increased the thermal stability of the hybrid duplexes (Sahu, B. et al. J. Org. Chem. 2011, 76, 5614-5627). Here, we applied atomic force microscopy (AFM) based single molecule force spectroscopy and dynamic force spectroscopy (DFS) to test the strength and stability of the hybrid 10 bp duplex. This hybrid duplex consisted of miniPEGγ-PNA and DNA of the same length (γ(MP)PNA-DNA), which we compared to a DNA duplex with a homologous sequence. AFM force spectroscopy data obtained at the same conditions showed that the γ(MP)PNA-DNA hybrid is more stable than the DNA counterpart, 65 ± 15 pN vs 47 ± 15 pN, respectively. The DFS measurements performed in a range of pulling speeds analyzed in the framework of the Bell-Evans approach yielded a dissociation constant, koff ≈ 0.030 ± 0.01 s⁻¹ for γ(MP)PNA-DNA hybrid duplex vs 0.375 ± 0.18 s⁻¹ for the DNA-DNA duplex suggesting that the hybrid duplex is much more stable. Correlating the high affinity of γ(MP)PNA-DNA to slow dissociation kinetics is consistent with prior bulk characterization by surface plasmon resonance. Given the growing interest in γ(MP)PNA as well as other synthetic DNA analogues, the use of single molecule experiments along with computational analysis of force spectroscopy data will provide direct characterization of various modifications as well as higher order structures such as triplexes and quadruplexes.

  10. Stability Control of Force-Reflected Nonlinear Multilateral Teleoperation System under Time-Varying Delays

    Directory of Open Access Journals (Sweden)

    Da Sun

    2016-01-01

    Full Text Available A novel control algorithm based on the modified wave-variable controllers is proposed to achieve accurate position synchronization and reasonable force tracking of the nonlinear single-master-multiple-slave teleoperation system and simultaneously guarantee overall system’s stability in the presence of large time-varying delays. The system stability in different scenarios of human and environment situations has been analyzed. The proposed method is validated through experimental work based on the 3-DOF trilateral teleoperation system consisting of three different manipulators. The experimental results clearly demonstrate the feasibility of the proposed algorithm to achieve high transparency and robust stability in nonlinear single-master-multiple-slave teleoperation system in the presence of time-varying delays.

  11. Stabilization of thin liquid films by repulsive van der waals force

    KAUST Repository

    Li, Erqiang

    2014-05-13

    Using high-speed video recording of bubble rise experiments, we study the stability of thin liquid films trapped between a rising bubble and a surfactant-free liquid-liquid meniscus interface. Using different combinations of nonpolar oils and water that are all immiscible, we investigate the extent to which film stability can be predicted by attractive and repulsive van der Waals (vdW) interactions that are indicated by the relative magnitude of the refractive indices of the liquid combinations, for example, water (refractive index, n = 1.33), perfluorohexane (n = 1.23), and tetradecane (n = 1.43). We show that, when the film-forming phase was oil (perfluorohexane or tetradecane), the stability of the film could always be predicted from the sign of the vdW interaction, with a repulsive vdW force resulting in a stable film and an attractive vdW force resulting in film rupture. However, if aqueous electrolyte is the film-forming bulk phase between the rising air bubble and the upper oil phase, the film always ruptured, even when a repulsive vdW interaction was predicted. We interpret these results as supporting the hypothesis that a short-ranged hydrophobic attraction determines the stability of the thin water film formed between an air phase and a nonpolar oil phase. © 2014 American Chemical Society.

  12. Assessing Power System Stability Following Load Changes and Considering Uncertainty

    Directory of Open Access Journals (Sweden)

    D. V. Ngo

    2018-04-01

    Full Text Available An increase in load capacity during the operation of a power system usually causes voltage drop and leads to system instability, so it is necessary to monitor the effect of load changes. This article presents a method of assessing the power system stability according to the load node capacity considering uncertainty factors in the system. The proposed approach can be applied to large-scale power systems for voltage stability assessment in real-time.

  13. Analytical Assessment for Transient Stability Under Stochastic Continuous Disturbances

    Energy Technology Data Exchange (ETDEWEB)

    Ju, Ping [Hohai Univ., Nanjing (China); Li, Hongyu [Hohai Univ., Nanjing (China); Gan, Chun [The Univ. of Tennessee, Knoxville, TN (United States); Liu, Yong [The Univ. of Tennessee, Knoxville, TN (United States); Yu, Yiping [Hohai Univ., Nanjing (China); Liu, Yilu [Univ. of Tennessee, Knoxville, TN (United States)

    2017-06-28

    Here, with the growing integration of renewable power generation, plug-in electric vehicles, and other sources of uncertainty, increasing stochastic continuous disturbances are brought to power systems. The impact of stochastic continuous disturbances on power system transient stability attracts significant attention. To address this problem, this paper proposes an analytical assessment method for transient stability of multi-machine power systems under stochastic continuous disturbances. In the proposed method, a probability measure of transient stability is presented and analytically solved by stochastic averaging. Compared with the conventional method (Monte Carlo simulation), the proposed method is many orders of magnitude faster, which makes it very attractive in practice when many plans for transient stability must be compared or when transient stability must be analyzed quickly. Also, it is found that the evolution of system energy over time is almost a simple diffusion process by the proposed method, which explains the impact mechanism of stochastic continuous disturbances on transient stability in theory.

  14. Guernsey; Financial System Stability Assessment-Update

    OpenAIRE

    International Monetary Fund

    2011-01-01

    Guernsey is a leading international insurance center in Europe. Its economy purely depends on the performance of the financial sector. As per the 2003 assessment under the Offshore Financial Center (OFC) program, it is found that the Guernsey Financial Services Commission (GFSC)’s powers have been strengthened in recent years and many recommendations of the 2003 Financial Sector Assessment Program (FSAP) have been implemented. The GFSC has developed a strategy for addressing banks' financial ...

  15. Application of stability enhancing minimum interfacial pressure force model for MARS

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Won Jae; Lim, Ho Gon; Kim, Kyung Doo; Ha, Kwi Seok

    2001-04-01

    For thermal-hydraulic modeling of two-phase flow systems, two-fluid model, which assumes that the pressures of liquid, vapor and interface are identical, a so-called single-pressure model, is commonly used in codes for nuclear reactor safety analyses. Typical two-phase model with single pressure assumption possesses complex characteristics that result in system being ill-posed. As a result, typical single pressure model may cause the unbounded growth of instabilities. In order to overcome the ill-posedness of single-pressure two-fluid model, a hyperbolic equation system has been developed by introducing an interfacial pressure force into single pressure two-fluid model. The potential impact of the present model on the stability of finite difference solution has been examined by Von-Neumann stability analysis. The obvious improvement in numerical stability has been found when a semi-implicit time advancement scheme is used. Numerical experiments using the pilot code were also performed for the conceptual problems. It was found that the result was consistent with numerical stability test. The new model was implemented to MARS using Two-step approach. Through the conceptual stability test problems and benchmark problems, the applicability of the new model was verified.

  16. Application of stability enhancing minimum interfacial pressure force model for MARS

    International Nuclear Information System (INIS)

    Lee, Won Jae; Lim, Ho Gon; Kim, Kyung Doo; Ha, Kwi Seok

    2001-04-01

    For thermal-hydraulic modeling of two-phase flow systems, two-fluid model, which assumes that the pressures of liquid, vapor and interface are identical, a so-called single-pressure model, is commonly used in codes for nuclear reactor safety analyses. Typical two-phase model with single pressure assumption possesses complex characteristics that result in system being ill-posed. As a result, typical single pressure model may cause the unbounded growth of instabilities. In order to overcome the ill-posedness of single-pressure two-fluid model, a hyperbolic equation system has been developed by introducing an interfacial pressure force into single pressure two-fluid model. The potential impact of the present model on the stability of finite difference solution has been examined by Von-Neumann stability analysis. The obvious improvement in numerical stability has been found when a semi-implicit time advancement scheme is used. Numerical experiments using the pilot code were also performed for the conceptual problems. It was found that the result was consistent with numerical stability test. The new model was implemented to MARS using Two-step approach. Through the conceptual stability test problems and benchmark problems, the applicability of the new model was verified

  17. Many-body forces and stability of the alkaline-earth tetramers

    International Nuclear Information System (INIS)

    Diaz-Torrejon, C.C.; Kaplan, Ilya G.

    2011-01-01

    Graphical abstract: Many-body forces effect. In a three-particle system, the two-body interaction energies depend upon coordinates of all three particles. The comparative study of the interaction energy and its many-body decomposition for alkaline-earths tetramers Be 4 , Mg 4 , and Ca 4 at the all-electron CCSD(T)/aug-cc-pVQZ level is performed. For study of dependence of the binding energy and the orbital population on the cluster size the corresponding dimers and trimers were also calculated at the same level of theory. In comparison with weakly bound dimers, the binding energy in trimers and, especially, in tetramers drastically increases; e.g., E b /N in Be 3 is 7 times larger and in Be 4 is 18.4 times larger than in Be 2 . This sharp increase is explained as a manifestation of many-body forces. The trimers and tetramers are stabilized by the three-body forces, whereas the two- and four-body forces are repulsive. The attractive contribution to the three-body forces has a three-atom electron exchange origin. The natural bond orbital (NBO) population analysis reveals a relatively large np-population in trimers and tetramers. The population of the valence np-orbitals leads to the sp-hybridization providing the covalent bonding. Research highlights: → The alkaline-earths trimers and tetramers are stabilized by the three-body forces. → Two- and four-body forces are repulsive for trimers and tetramers. → The attractive contribution to the three-body forces has a three-atom electron exchange origin. → The population of the np-orbitals leads to the sp-hybridization providing the covalent bonding. - Abstract: The comparative study of the interaction energy and its many-body decomposition for Be 4 , Mg 4 , and Ca 4 at the all-electron CCSD(T)/aug-cc-pVQZ level is performed. For study of dependence of the binding energy and the orbital population on the cluster size the corresponding dimers and trimers were also calculated at the same level of theory. In

  18. Structure and stability of semiconductor tip apexes for atomic force microscopy

    International Nuclear Information System (INIS)

    Pou, P; Perez, R; Ghasemi, S A; Goedecker, S; Jelinek, P; Lenosky, T

    2009-01-01

    The short range force between the tip and the surface atoms, that is responsible for atomic-scale contrast in atomic force microscopy (AFM), is mainly controlled by the tip apex. Thus, the ability to image, manipulate and chemically identify single atoms in semiconductor surfaces is ultimately determined by the apex structure and its composition. Here we present a detailed and systematic study of the most common structures that can be expected at the apex of the Si tips used in experiments. We tackle the determination of the structure and stability of Si tips with three different approaches: (i) first principles simulations of small tip apexes; (ii) simulated annealing of a Si cluster; and (iii) a minima hopping study of large Si tips. We have probed the tip apexes by making atomic contacts between the tips and then compared force-distance curves with the experimental short range forces obtained with dynamic force spectroscopy. The main conclusion is that although there are multiple stable solutions for the atomically sharp tip apexes, they can be grouped into a few types with characteristic atomic structures and properties. We also show that the structure of the last atomic layers in a tip apex can be both crystalline and amorphous. We corroborate that the atomically sharp tips are thermodynamically stable and that the tip-surface interaction helps to produce the atomic protrusion needed to get atomic resolution.

  19. Quantitative assessment of contact and non-contact lateral force calibration methods for atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tran Khac, Bien Cuong; Chung, Koo-Hyun, E-mail: khchung@ulsan.ac.kr

    2016-02-15

    Atomic Force Microscopy (AFM) has been widely used for measuring friction force at the nano-scale. However, one of the key challenges faced by AFM researchers is to calibrate an AFM system to interpret a lateral force signal as a quantifiable force. In this study, five rectangular cantilevers were used to quantitatively compare three different lateral force calibration methods to demonstrate the legitimacy and to establish confidence in the quantitative integrity of the proposed methods. The Flat-Wedge method is based on a variation of the lateral output on a surface with flat and changing slopes, the Multi-Load Pivot method is based on taking pivot measurements at several locations along the cantilever length, and the Lateral AFM Thermal-Sader method is based on determining the optical lever sensitivity from the thermal noise spectrum of the first torsional mode with a known torsional spring constant from the Sader method. The results of the calibration using the Flat-Wedge and Multi-Load Pivot methods were found to be consistent within experimental uncertainties, and the experimental uncertainties of the two methods were found to be less than 15%. However, the lateral force sensitivity determined by the Lateral AFM Thermal-Sader method was found to be 8–29% smaller than those obtained from the other two methods. This discrepancy decreased to 3–19% when the torsional mode correction factor for an ideal cantilever was used, which suggests that the torsional mode correction should be taken into account to establish confidence in Lateral AFM Thermal-Sader method. - Highlights: • Quantitative assessment of three lateral force calibration methods for AFM. • Advantages and disadvantages of three different lateral force calibration method. • Implementation of Multi-Load Pivot method as non-contact calibration technique. • The torsional mode correction for Lateral AFM Thermal-Sader method.

  20. Quantitative assessment of contact and non-contact lateral force calibration methods for atomic force microscopy

    International Nuclear Information System (INIS)

    Tran Khac, Bien Cuong; Chung, Koo-Hyun

    2016-01-01

    Atomic Force Microscopy (AFM) has been widely used for measuring friction force at the nano-scale. However, one of the key challenges faced by AFM researchers is to calibrate an AFM system to interpret a lateral force signal as a quantifiable force. In this study, five rectangular cantilevers were used to quantitatively compare three different lateral force calibration methods to demonstrate the legitimacy and to establish confidence in the quantitative integrity of the proposed methods. The Flat-Wedge method is based on a variation of the lateral output on a surface with flat and changing slopes, the Multi-Load Pivot method is based on taking pivot measurements at several locations along the cantilever length, and the Lateral AFM Thermal-Sader method is based on determining the optical lever sensitivity from the thermal noise spectrum of the first torsional mode with a known torsional spring constant from the Sader method. The results of the calibration using the Flat-Wedge and Multi-Load Pivot methods were found to be consistent within experimental uncertainties, and the experimental uncertainties of the two methods were found to be less than 15%. However, the lateral force sensitivity determined by the Lateral AFM Thermal-Sader method was found to be 8–29% smaller than those obtained from the other two methods. This discrepancy decreased to 3–19% when the torsional mode correction factor for an ideal cantilever was used, which suggests that the torsional mode correction should be taken into account to establish confidence in Lateral AFM Thermal-Sader method. - Highlights: • Quantitative assessment of three lateral force calibration methods for AFM. • Advantages and disadvantages of three different lateral force calibration method. • Implementation of Multi-Load Pivot method as non-contact calibration technique. • The torsional mode correction for Lateral AFM Thermal-Sader method.

  1. Assessing control of postural stability in community-living older adults using performance-based limits of stability

    Directory of Open Access Journals (Sweden)

    Boissy Patrick

    2008-03-01

    Full Text Available Abstract Background Balance disability measurements routinely used to identify fall risks in frail populations have limited value in the early detection of postural stability deficits in community-living older adults. The objectives of the study were to 1 measure performance-based limits of stability (LOS in community-living older adults and compare them to theoretical LOS computed from data proposed by the Balance Master® system, 2 explore the feasibility of a new measurement approach based on the assessment of postural stability during weight-shifting tasks at performance-based LOS, 3 quantify intra-session performance variability during multiple trials using the performance-based LOS paradigm. Methods Twenty-four healthy community-living older adults (10 men, 14 women aged between 62 to 85 (mean age ± sd, 71.5 ± 6 yrs participated in the study. Subjects' performance-based LOS were established by asking them to transfer their body weight as far as possible in three directions (forward, right and left without changing their base of support. LOS were computed as the maximal excursion of the COP in each direction among three trials. Participants then performed two experimental tasks that consisted in controlling, with the assistance of visual feedback, their centre of pressure (COP within two predefined targets set at 100% of their performance-based LOS. For each tasks 8 trials were performed. Ground reaction forces and torques during performance-based LOS evaluation and experimental tasks were recorded with a force plate. Sway area and medio-lateral mean COP displacement speed variables were extracted from force plate recordings. Results Significant differences between theoretical LOS computed from maximum leaning angles derived from anthropometric characteristics and performance-based LOS were observed. Results showed that a motor learning effect was present as the participants optimized their weight-shifting strategy through the first three

  2. Stability enhancement of an atomic force microscope for long-term force measurement including cantilever modification for whole cell deformation

    Science.gov (United States)

    Weafer, P. P.; McGarry, J. P.; van Es, M. H.; Kilpatrick, J. I.; Ronan, W.; Nolan, D. R.; Jarvis, S. P.

    2012-09-01

    Atomic force microscopy (AFM) is widely used in the study of both morphology and mechanical properties of living cells under physiologically relevant conditions. However, quantitative experiments on timescales of minutes to hours are generally limited by thermal drift in the instrument, particularly in the vertical (z) direction. In addition, we demonstrate the necessity to remove all air-liquid interfaces within the system for measurements in liquid environments, which may otherwise result in perturbations in the measured deflection. These effects severely limit the use of AFM as a practical tool for the study of long-term cell behavior, where precise knowledge of the tip-sample distance is a crucial requirement. Here we present a readily implementable, cost effective method of minimizing z-drift and liquid instabilities by utilizing active temperature control combined with a customized fluid cell system. Long-term whole cell mechanical measurements were performed using this stabilized AFM by attaching a large sphere to a cantilever in order to approximate a parallel plate system. An extensive examination of the effects of sphere attachment on AFM data is presented. Profiling of cantilever bending during substrate indentation revealed that the optical lever assumption of free ended cantilevering is inappropriate when sphere constraining occurs, which applies an additional torque to the cantilevers "free" end. Here we present the steps required to accurately determine force-indentation measurements for such a scenario. Combining these readily implementable modifications, we demonstrate the ability to investigate long-term whole cell mechanics by performing strain controlled cyclic deformation of single osteoblasts.

  3. 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.

  4. Effect of weak geometrical forcing on the stability of Taylor-vortex flow

    International Nuclear Information System (INIS)

    Pan Xiaolong; Khayat, Roger E

    2008-01-01

    Linear stability analysis of fully developed axisymmetric steady and spatially modulated Taylor-Couette flow is carried out in the narrow-gap limit. The inner cylinder is sinusoidally modulated and rotating, while the outer cylinder is straight and at rest. The modulation amplitude is assumed to be small, and the base steady flow is determined using a regular perturbation expansion of the flow field coupled to a variable-step finite-difference scheme. The disturbance flow equations are derived within the framework of Floquet theory and solved using a nonlinear two-point boundary-value approach. In contrast to unforced Taylor-Couette flow, only vortical base flow is possible in the forced case. It is found that the forcing tends to generally destabilize the base flow, especially around the critical point. Both the critical Taylor number and wavenumber are found to decrease essentially linearly with modulation amplitude.

  5. Dynamic stability of a cantilevered Timoshenko beam on partial elastic foundations subjected to a follower force

    International Nuclear Information System (INIS)

    Ryu, Bong Jo; Shin, Kwang Bok; Yim, Kyung Bin; Yoon, Young Sik

    2006-01-01

    This paper presents the dynamic stability of a cantilevered Timoshenko beam with a concentrated mass, partially attached to elastic foundations, and subjected to a follower force. Governing equations are derived from the extended Hamilton's principle, and FEM is applied to solve the discretized equation. The influence of some parameters such as the elastic foundation parameter, the positions of partial elastic foundations, shear deformations, the rotary inertia of the beam, and the mass and the rotary inertia of the concentrated mass on the critical flutter load is investigated. Finally, the optimal attachment ratio of partial elastic foundation that maximizes the critical flutter load is presented

  6. Parabolized Stability Equations analysis of nonlinear interactions with forced eigenmodes to control subsonic jet instabilities

    International Nuclear Information System (INIS)

    Itasse, Maxime; Brazier, Jean-Philippe; Léon, Olivier; Casalis, Grégoire

    2015-01-01

    Nonlinear evolution of disturbances in an axisymmetric, high subsonic, high Reynolds number hot jet with forced eigenmodes is studied using the Parabolized Stability Equations (PSE) approach to understand how modes interact with one another. Both frequency and azimuthal harmonic interactions are analyzed by setting up one or two modes at higher initial amplitudes and various phases. While single mode excitation leads to harmonic growth and jet noise amplification, controlling the evolution of a specific mode has been made possible by forcing two modes (m 1 , n 1 ), (m 2 , n 2 ), such that the difference in azimuth and in frequency matches the desired “target” mode (m 1 − m 2 , n 1 − n 2 ). A careful setup of the initial amplitudes and phases of the forced modes, defined as the “killer” modes, has allowed the minimizing of the initially dominant instability in the near pressure field, as well as its estimated radiated noise with a 15 dB loss. Although an increase of the overall sound pressure has been found in the range of azimuth and frequency analyzed, the present paper reveals the possibility to make the initially dominant instability ineffective acoustically using nonlinear interactions with forced eigenmodes

  7. Parabolized Stability Equations analysis of nonlinear interactions with forced eigenmodes to control subsonic jet instabilities

    Energy Technology Data Exchange (ETDEWEB)

    Itasse, Maxime, E-mail: Maxime.Itasse@onera.fr; Brazier, Jean-Philippe, E-mail: Jean-Philippe.Brazier@onera.fr; Léon, Olivier, E-mail: Olivier.Leon@onera.fr; Casalis, Grégoire, E-mail: Gregoire.Casalis@onera.fr [Onera - The French Aerospace Lab, F-31055 Toulouse (France)

    2015-08-15

    Nonlinear evolution of disturbances in an axisymmetric, high subsonic, high Reynolds number hot jet with forced eigenmodes is studied using the Parabolized Stability Equations (PSE) approach to understand how modes interact with one another. Both frequency and azimuthal harmonic interactions are analyzed by setting up one or two modes at higher initial amplitudes and various phases. While single mode excitation leads to harmonic growth and jet noise amplification, controlling the evolution of a specific mode has been made possible by forcing two modes (m{sub 1}, n{sub 1}), (m{sub 2}, n{sub 2}), such that the difference in azimuth and in frequency matches the desired “target” mode (m{sub 1} − m{sub 2}, n{sub 1} − n{sub 2}). A careful setup of the initial amplitudes and phases of the forced modes, defined as the “killer” modes, has allowed the minimizing of the initially dominant instability in the near pressure field, as well as its estimated radiated noise with a 15 dB loss. Although an increase of the overall sound pressure has been found in the range of azimuth and frequency analyzed, the present paper reveals the possibility to make the initially dominant instability ineffective acoustically using nonlinear interactions with forced eigenmodes.

  8. Prediction of dynamic cutting force and regenerative chatter stability in inserted cutters milling

    Science.gov (United States)

    Li, Zhongqun; Liu, Qiang; Yuan, Songmei; Huang, Kaisheng

    2013-05-01

    Currently, the modeling of cutting process mainly focuses on two aspects: one is the setup of the universal cutting force model that can be adapted to a broader cutting condition; the other is the setup of the exact cutting force model that can accurately reflect a true cutting process. However, there is little research on the prediction of chatter stablity in milling. Based on the generalized mathematical model of inserted cutters introduced by ENGIN, an improved geometrical, mechanical and dynamic model for the vast variety of inserted cutters widely used in engineering applications is presented, in which the average directional cutting force coefficients are obtained by means of a numerical approach, thus leading to an analytical determination of stability lobes diagram (SLD) on the axial depth of cut. A new kind of SLD on the radial depth of cut is also created to satisfy the special requirement of inserted cutter milling. The corresponding algorithms used for predicting cutting forces, vibrations, dimensional surface finish and stability lobes in inserted cutter milling under different cutting conditions are put forward. Thereafter, a dynamic simulation module of inserted cutter milling is implemented by using hybrid program of Matlab with Visual Basic. Verification tests are conducted on a vertical machine center for Aluminum alloy LC4 by using two different types of inserted cutters, and the effectiveness of the model and the algorithm is verified by the good agreement of simulation result with that of cutting tests under different cutting conditions. The proposed model can predict the cutting process accurately under a variety of cutting conditions, and a high efficient and chatter-free milling operation can be achieved by a cutting condition optimization in industry applications.

  9. Assessing Grasp Stability Based on Learning and Haptic Data

    DEFF Research Database (Denmark)

    Bekiroglu, Yasemin; Laaksonen, Janne; Jørgensen, Jimmy Alison

    2011-01-01

    a probabilistic learning framework to assess grasp stability and demonstrate that knowledge about grasp stability can be inferred using information from tactile sensors. Experiments on both simulated and real data are shown. The results indicate that the idea to exploit the learning approach is applicable...... data and machine-learning methods, including AdaBoost, support vector machines (SVMs), and hidden Markov models (HMMs). In particular, we study the effect of different sensory streams to grasp stability. This includes object information such as shape; grasp information such as approach vector; tactile...

  10. Assessment of the mechanical stability of underground excavations

    International Nuclear Information System (INIS)

    Kuroki, Shigemori; Taniguchi, Wataru

    1999-01-01

    Each tunnel in the underground high level radioactive waste repository must be mechanically stable to maintain safety throughout the construction, emplacement operations and closure phase. The mechanical stability of underground excavations were assessed using a theoretical analysis and a finite element method taking a wide range of geological environment in Japan into consideration to establish confidence in the construction of disposal facilities. The results show that it is possible to maintain the mechanical stability with adequate tunnel spacing and disposal pit pitch and proper mechanical support. The procedure used for the analysis of the mechanical stability in the H12 report and the results are described in this report. (author)

  11. Teleoperator comfort and psychometric stability: Criteria for limiting master-controller forces of operation and feedback during telemanipulation

    Science.gov (United States)

    Wiker, Steven F.; Hershkowitz, Elaine; Zik, John

    1989-01-01

    The following question is addressed: How much force should operators exert, or experience, when operating a telemanipulator master-controller for sustained periods without encountering significant fatigue and discomfort, and without loss of stability in psychometric perception of force. The need to minimize exertion demands to avoid fatigue is diametrically opposed by the need to present a wide range of force stimuli to enhance perception of applied or reflected forces. For 104 minutes subjects repetitiously performed a series of 15 s isometric pinch grasps; controlled at 5, 15, and 25 percent of their maximum voluntary strength. Cyclic pinch grasps were separated by rest intervals of 7.5 and 15 s. Upon completion of every 10 minute period, subjects interrupted grasping activities to gage the intensity of fatigue and discomfort in the hand and forearm using a cross-modal matching technique. A series of psychometric tests were then conducted to determine accuracy and stability in the subject's perception of force experienced. Results showed that onset of sensations of discomfort and fatigue were dependent upon the magnitude of grasp force, work/rest ratio, and progression of task. Declines in force magnitude estimation slopes, indicating a reduction in force perception sensitivity, occurred with increased grasp force when work/rest ratios were greater than 1.0. Specific recommendations for avoiding discomfort and shifts in force perception, by limiting pinch grasp force required for master-controller operation and range of force reflection or work/rest ratios, are provided.

  12. Force Plate Assessment of Quiet Standing Balance Control: Perspectives on Clinical Application within Stroke Rehabilitation

    Directory of Open Access Journals (Sweden)

    Avril Mansfield

    2015-01-01

    Full Text Available Assessment of balance control is essential to guide physical rehabilitation poststroke. However, current observational assessment tools available to physiotherapists provide limited information about underlying dyscontrol. This paper describes a force plate-based assessment of quiet standing balance control that we have implemented for individuals attending inpatient stroke rehabilitation. The assessment uses two force plates to measure location of ground reaction forces to maintain stability in quiet standing in five conditions (eyes open, eyes closed, standing symmetrically, and maximal loading on the less-affected and more-affected limbs. Measures of interest are variability of the centers of pressure under each foot and both feet combined, weight-bearing asymmetry, and correlation of center of pressure fluctuations between limbs. We present representative values for the above-mentioned measures and case examples to illustrate how the assessment can reveal patient-specific balance control problems and direct treatment. We identify limitations to our current assessment and recommendations for future research.

  13. Transient stability risk assessment of power systems incorporating wind farms

    DEFF Research Database (Denmark)

    Miao, Lu; Fang, Jiakun; Wen, Jinyu

    2013-01-01

    fed induction generator has been established. Wind penetration variation and multiple stochastic factors of power systems have been considered. The process of transient stability risk assessment based on the Monte Carlo method has been described and a comprehensive risk indicator has been proposed......Large-scale wind farm integration has brought several aspects of challenges to the transient stability of power systems. This paper focuses on the research of the transient stability of power systems incorporating with wind farms by utilizing risk assessment methods. The detailed model of double....... An investigation has been conducted into an improved 10-generator 39-bus system with a wind farm incorporated to verify the validity and feasibility of the risk assessment method proposed....

  14. Determination of tensile forces to enhance the supply stability of reinforced fiber

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kun Woo; Lee, Jae Wook; Jang, Jin Seok; Jeong, Myeong Sik; Oh, Joo Young; Kang, Hoon; Kang, Ji Heon [Daegyeong Regional Division, Korea Institute of Industrial Technology, Daegu (Korea, Republic of); Kim, Hyung Ryul [Agency for Defense Development, Changwon (Korea, Republic of); Yoo, Wan Suk [School of Mechanical Engineering, Pusan National University, Busan (Korea, Republic of)

    2016-12-15

    The manufacturing process of long fiber thermoplastic is initiated by supplying reinforced fiber wound in a spool dispenser. If problems such as tangling or kinking occur in the apparatus used for supplying the reinforced fiber in the long-fiber thermoplastic direct process, the productivity of the long-fiber thermoplastic decreases. Therefore, it is important to enhance the supply stability of reinforced fiber. In general, the increase in supply stability can be achieved by maintaining a steady balloon shape that is controlled by the unwinding velocity or tensile force of the reinforced fiber. In this research, the range of suitable tensile force was determined under the assumption that the unwinding velocity remained constant. The reinforced fiber was assumed to be inextensible, homogeneous, and isotropic and to have uniform density. The transient-state unwinding equation of motion to analyze the unwinding motion of reinforced fiber can be derived by using Hamilton’s principle for an open system in which mass can change within a control volume. In the process of solving the transient-state unwinding equation of motion, the exact two-point boundary conditions are adopted for each time step.

  15. Final Environmental Assessment for the First Air Force Air Operations Center, First Air Force Headquarters/Air Force Forces Center, and Highway 98 Overpass at Tyndall Air Force Base, Florida

    Science.gov (United States)

    2004-01-01

    no comments regarding the Draft Environmental Assessment for the First Air Force Operations Center, First Air Force Headquarters/Air Force Forces...COUNCIL ] No Comment BAY - BAY COUNTY No Final Comments Received ENVIRONMENTAL POLICY UNIT - OFFICE OF POLICY AND BUDGET, ENVIRONMENTAL POLICY UNIT NO ...CONSERVATION COMMISSION [ NO COMMENT BY BRIAN BARNETT ON 4/12/04. [STATE - FLORIDA DEPARTMENT OF STATE [ No Comment [TRANSPORTATION - FLORIDA DEPARTMENT

  16. Assessing fly ash treatment: Remediation and stabilization of heavy metals

    DEFF Research Database (Denmark)

    Lima, A.T.; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

    2012-01-01

    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialy......Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through...

  17. The role of intrinsic muscle properties for stable hopping-stability is achieved by the force-velocity relation

    International Nuclear Information System (INIS)

    Haeufle, D F B; Grimmer, S; Seyfarth, A

    2010-01-01

    A reductionist approach was presented to investigate which level of detail of the physiological muscle is required for stable locomotion. Periodic movements of a simplified one-dimensional hopping model with a Hill-type muscle (one contractile element, neither serial nor parallel elastic elements) were analyzed. Force-length and force-velocity relations of the muscle were varied in three levels of approximation (constant, linear and Hill-shaped nonlinear) resulting in nine different hopping models of different complexity. Stability of these models was evaluated by return map analysis and the performance by the maximum hopping height. The simplest model (constant force-length and constant force-velocity relations) outperformed all others in the maximum hopping height but was unstable. Stable hopping was achieved with linear and Hill-shaped nonlinear characteristic of the force-velocity relation. The characteristics of the force-length relation marginally influenced hopping stability. The results of this approach indicate that the intrinsic properties of the contractile element are responsible for stabilization of periodic movements. This connotes that (a) complex movements like legged locomotion could benefit from stabilizing effects of muscle properties, and (b) technical systems could benefit from the emerging stability when implementing biological characteristics into artificial muscles.

  18. Effect of compressive force on aeroelastic stability of a strut-braced wing

    Science.gov (United States)

    Sulaeman, Erwin

    2002-01-01

    Recent investigations of a strut-braced wing (SBW) aircraft show that, at high positive load factors, a large tensile force in the strut leads to a considerable compressive axial force in the inner wing, resulting in a reduced bending stiffness and even buckling of the wing. Studying the influence of this compressive force on the structural response of SBW is thus of paramount importance in the early stage of SBW design. The purpose of the this research is to investigate the effect of compressive force on aeroelastic stability of the SBW using efficient structural finite element and aerodynamic lifting surface methods. A procedure is developed to generate wing stiffness distribution for detailed and simplified wing models and to include the compressive force effect in the SBW aeroelastic analysis. A sensitivity study is performed to generate response surface equations for the wing flutter speed as functions of several design variables. These aeroelastic procedures and response surface equations provide a valuable tool and trend data to study the unconventional nature of SBW. In order to estimate the effect of the compressive force, the inner part of the wing structure is modeled as a beam-column. A structural finite element method is developed based on an analytical stiffness matrix formulation of a non-uniform beam element with arbitrary polynomial variations in the cross section. By using this formulation, the number of elements to model the wing structure can be reduced without degrading the accuracy. The unsteady aerodynamic prediction is based on a discrete element lifting surface method. The present formulation improves the accuracy of existing lifting surface methods by implementing a more rigorous treatment on the aerodynamic kernel integration. The singularity of the kernel function is isolated by implementing an exact expansion series to solve an incomplete cylindrical function problem. A hybrid doublet lattice/doublet point scheme is devised to reduce

  19. Incentives and stability of international climate coalitions: An integrated assessment

    International Nuclear Information System (INIS)

    Bosetti, Valentina; Carraro, Carlo; De Cian, Enrica; Massetti, Emanuele; Tavoni, Massimo

    2013-01-01

    This paper analyses the incentives to participate in an international climate agreement and the stability of the resulting climate coalition using the integrated assessment model WITCH. Coalition stability is assessed under alternative assumptions concerning the pure rate of time preference, the aggregation of social welfare, and the severity of climate damages. The profitability, stability, and strong potential internal stability of a number of coalitions, those potentially effective in reducing GHG emissions, is explored in the paper. The main conclusion is that only the grand coalition, i.e. a coalition where all world regions cooperate to reduce emissions, can maintain GHG concentration below 550 ppm CO 2 -eq. However, this coalition is not internally stable, even when allowing for monetary transfers across world regions. Nonetheless, the paper also shows that strongly potentially internally stable coalitions exist, though of smaller size, which can mitigate global warming and limit GHG concentrations to 600 ppm CO 2 -eq. - Highlights: ► We analyse climate coalitions with an integrated assessment model. ► Coalitions’ profitability and stability is analysed under alternative assumptions. ► Effective coalitions should include larger emitters (such as India and China). ► A coalition that achieves 550 ppm CO 2 -eq is not internally stable. ► A stable coalition can achieve around 518 ppme in 2050 and 600 ppme in 2100

  20. A Comparison of Balance and Postural Stability Assessment Tools: BESS Versus NeuroCom Balance Manager

    OpenAIRE

    Joliffe, Jamie

    2012-01-01

    Postural stability assessment tools are one of the many ways concussions can be assessed and return to play decisions can be made; two of which are the Balance Error Scoring System (BESS) and force plate technology. OBJECTIVE: Validate the modified BESS used by Utah State University by comparing it to equivalent tests on the NeuroCom Balance Manager System. METHODS: 114 current or previous Utah State football players ranging in age from 18-24. Each athlete conducted a baseline BESS test durin...

  1. Title Qualitative stability assessment of cut slopes along the national ...

    Indian Academy of Sciences (India)

    64

    Qualitative stability assessment of cut slopes along the national highway- 05 around Jhakri area, .... The rock types in the area are augen migmatite, biotite gneiss, quartz ..... slopes using quantified method (Sonmez and Ulusay 1999, 2002). Finally a .... through numerical simulation is suggested by many researchers. 1. 2. 3.

  2. An Artificial Intelligence Approach to Transient Stability Assessment

    OpenAIRE

    Akella, Vijay Ahaskar; Khincha, HP; Kumar, Sreerama R

    1991-01-01

    An artificial intelligence approach to online transient stability assessment is briefly discussed, and some crucial requirements for this algorithm are identified. Solutions to these are proposed. Some new attributes are suggested so as to reflect machine dynamics and changes in the network. Also a new representative learning set algorithm has been developed.

  3. Graphical assessment of yield stability and adaptation in cowpeas ...

    African Journals Online (AJOL)

    Graphical assessment of yield stability and adaptation in cowpeas (Vigna unguiculata (L) Walp). DK Ojo, MS Oduola, OA Oduwaye. Abstract. No Abstract. Nigerian Journal of Genetics Vol. 20 2006: pp. 17-25. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  4. STUDY OF STATIC AND DYNAMIC STABILITY OF THIN-WALLED BARS EXCITED BY PERIODICAL AXIAL EXTERNAL FORCES.

    Directory of Open Access Journals (Sweden)

    Minodora Maria PASĂRE

    2010-10-01

    Full Text Available In these paper, starting from the relations for the displacements and spinning the transversal section of a bar with thin walls of sections opened expressed by the corresponding influence functions and introducing the components of the exterior forces distributed and the moments of the exterior forces distributed due to the inertia forces, the exciting axial forces together with the following effect of these and of the reaction forces of the elastic environment for leaning it may reach to the system of the equations of parametric vibrations under the form of three integral equation These equations may serve for the study of vibrations of the bars, to study the static stability and to study the dynamic stability

  5. The Self-esteem Stability Scale (SESS) for Cross-Sectional Direct Assessment of Self-esteem Stability

    OpenAIRE

    Tobias Altmann; Marcus Roth

    2018-01-01

    Self-esteem stability describes fluctuations in the level of self-esteem experienced by individuals over a brief period of time. In recent decades, self-esteem stability has repeatedly been shown to be an important variable affecting psychological functioning. However, measures of self-esteem stability are few and lacking in validity. In this paper, we present the Self-Esteem Stability Scale (SESS), a unidimensional and very brief scale to directly assess self-esteem stability. In four studie...

  6. Stability Assessment as a Criterion of Stabilization of the Movement Trajectory of Mobile Crane Working Elements

    Science.gov (United States)

    Kacalak, W.; Budniak, Z.; Majewski, M.

    2018-02-01

    The article presents a stability assessment method of the mobile crane handling system based on the safety indicator values that were accepted as the trajectory optimization criterion. With the use of the mathematical model built and the model built in the integrated CAD/CAE environment, analyses were conducted of the displacements of the mass centre of the crane system, reactions of the outrigger system, stabilizing and overturning torques that act on the crane as well as the safety indicator values for the given movement trajectories of the crane working elements.

  7. SPI Project Criticality Task Force initial review and assessment

    International Nuclear Information System (INIS)

    McKinley, K.B.; Cannon, J.W.; Marsden, R.S.; Worle, H.A.

    1980-03-01

    The Slagging Pyrolysis Incinerator (SPI) Facility is being developed to process transuranic waste stored and buried at the Idaho National Engineering Laboratory (INEL) into a chemically inert, physically stable, basalt-like residue acceptable for a Federal Repository. A task force was established by the SPI Project Division to review and assess all aspects of criticality safety for the SPI Facility. This document presents the initial review, evaluations, and recommendations of the task force and includes the following: background information on waste characterization, and criticality control approaches and philosophies, a description of the SPI Facility Waste Processing Building, a review and assessment of potentially relevant codes and regulations; a review and assessment of the present state of criticality and assaying/monitoring studies, and recommendations for changes in and additions to these studies. The review and assessment of potentially relevant codes and regulations indicate that ERDAM 0530, Nuclear Criticality Safety should be the controlling document for criticality safety for the SPI Project. In general, the criticality control approaches and philosophies for the SPI Project comply with this document

  8. Impact assessment of land use planning driving forces on environment

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Longgao, E-mail: chenlonggao@163.com [Institute of Land Resources, Jiangsu Normal University (JSNU), Xuzhou 221116 (China); Yang, Xiaoyan [Institute of Land Resources, Jiangsu Normal University (JSNU), Xuzhou 221116 (China); School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116 (China); Chen, Longqian [School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116 (China); Li, Long [Department of Geography, Vrije Universiteit Brussel, Brussels 1050 (Belgium)

    2015-11-15

    Land use change may exert a negative impact on environmental quality. A state–impact–state (SIS) model describing a state transform under certain impacts has been integrated into land use planning (LUP) environmental impact assessment (LUPEA). This logical model is intuitive and easy to understand, but the exploration of impact is essential to establish the indicator system and to identify the scope of land use environmental impact when it is applied to a specific region. In this study, we investigated environmental driving forces from land use planning (LUPF), along with the conception, components, scope, and impact of LUPF. This method was illustrated by a case study in Zoucheng, China. Through the results, we concluded that (1) the LUPF on environment are impacts originated from the implementation of LUP on a regional environment, which are characterized by four aspects: magnitude, direction, action point, and its owner; (2) various scopes of LUPF on individual environmental elements based on different standards jointly define the final scope of LUPEA; (3) our case study in Zoucheng demonstrates the practicability of this proposed approach; (4) this method can be embedded into LUPEA with direction, magnitudes, and scopes of the LUPF on individual elements obtained, and the identified indicator system can be directly employed into LUPEA and (5) the assessment helps to identify key indicators and to set up a corresponding strategy to mitigate the negative impact of LUP on the environment, which are two important objectives of strategic environmental assessment (SEA) in LUP. - Highlights: • Environmental driving forces from land use planning (LUPF) are investigated and categorized. • Our method can obtains the direction, magnitudes and scopes of environmental driving forces. • The LUPEA scope is determined by the combination of various scopes of LUPF on individual elements. • LUPF assessment can be embedded into LUPEA. • The method can help to

  9. [Experimental study on carbon fiber reinforced plastic plate--analysis of stabilizing force required for plate].

    Science.gov (United States)

    Iizuka, H

    1990-11-01

    Plates currently in use for the management of bone fracture made of metal present with various problems. We manufactured carbon fiber reinforced plastic (CFRP) plates from Pyrofil T/530 puriplegs overlaid at cross angles of +/- 10 degrees, +/- 20 degrees, and +/- 30 degrees for trial and carried out an experimental study on rabbit tibiofibular bones using 316L stainless steel plates of comparable shape and size as controls. The results indicate the influence of CFRP plate upon cortical bone was milder than that of stainless steel plate, with an adequate stabilizing force for the repair of fractured rabbit tibiofibular bones. CFRP has the advantages over metals of being virtually free from corrosion and fatigue, reasonably radiolucent and able to meet a wide range of mechanical requirements. This would make CFRP plate quite promising as a new devices of treating fracture of bones.

  10. Stabilization of car-caravan combination using independent steer and drive/or brake forces distribution

    Directory of Open Access Journals (Sweden)

    Ossama Mokhiamar

    2015-09-01

    Full Text Available Once a combined vehicle becomes unstable, it is very difficult for a driver to stabilize it especially under severe driving conditions, such as turning with braking. This is mainly due to the effect of the towed vehicle on the towing vehicle through the hitch jackknifing. This effect makes the handling characteristics of a car-caravan combination different from those of a single vehicle. Therefore, this paper proposes a control design concept for an optimum distribution of longitudinal and lateral forces of the four tires of a towing vehicle. The mean objectives of the control system were to stabilize the motion of an articulated vehicle utilizing the tires entire ability in both longitudinal and lateral directions as well as to make the handling characteristics of an articulated vehicle similar to those of a single one. The sliding control law based on vehicle planar equations of motion is used to derive the control laws. The proposed control system is evaluated under severe driving conditions and compared with the results of integrated control systems. The robustness of the articulated vehicle motion with the proposed control against the coefficient of friction variation is discussed.

  11. Influence of Dynamic Neuromuscular Stabilization Approach on Maximum Kayak Paddling Force

    Directory of Open Access Journals (Sweden)

    Davidek Pavel

    2018-03-01

    Full Text Available The purpose of this study was to examine the effect of Dynamic Neuromuscular Stabilization (DNS exercise on maximum paddling force (PF and self-reported pain perception in the shoulder girdle area in flatwater kayakers. Twenty male flatwater kayakers from a local club (age = 21.9 ± 2.4 years, body height = 185.1 ± 7.9 cm, body mass = 83.9 ± 9.1 kg were randomly assigned to the intervention or control groups. During the 6-week study, subjects from both groups performed standard off-season training. Additionally, the intervention group engaged in a DNS-based core stabilization exercise program (quadruped exercise, side sitting exercise, sitting exercise and squat exercise after each standard training session. Using a kayak ergometer, the maximum PF stroke was measured four times during the six weeks. All subjects completed the Disabilities of the Arm, Shoulder and Hand (DASH questionnaire before and after the 6-week interval to evaluate subjective pain perception in the shoulder girdle area. Initially, no significant differences in maximum PF and the DASH questionnaire were identified between the two groups. Repeated measures analysis of variance indicated that the experimental group improved significantly compared to the control group on maximum PF (p = .004; Cohen’s d = .85, but not on the DASH questionnaire score (p = .731 during the study. Integration of DNS with traditional flatwater kayak training may significantly increase maximum PF, but may not affect pain perception to the same extent.

  12. Assessing resistance of stabilized corrosion resistant steels to intergranular corrosion

    International Nuclear Information System (INIS)

    Karas, A.; Cihal, V. Jr.; Vanek, V.; Herzan, J.; Protiva, K.; Cihal, V.

    1987-01-01

    Resistance to intergranular corrosion was determined for four types of titanium-stabilized steels from the coefficients of stabilization efficiency according to the degree the chemical composition was known. The ATA SUPER steel showed the highest resistance parameter value. The resistance of this type of steel of a specific composition, showing a relatively low value of mean nitrogen content was compared with steel of an optimized chemical composition and with low-carbon niobium stabilized, molybdenum modified steels. The comparison showed guarantees of a sufficient resistance of the steel to intergranular corrosion. The method of assessing the resistance to intergranular corrosion using the calculation of the minimum content of Cr', i.e., the effective chromium content, and the maximum effective carbon content C' giving the resistance parameter k seems to be prospective for practical use in the production of corrosion resistant steels. (author). 1 tab., 5 figs., 15 refs

  13. Periodic Forcing of Inhibition-Stabilized Networks: Nonlinear Resonances and Phase-Amplitude Coupling

    Science.gov (United States)

    Veltz, Romain; Sejnowski, Terrence J.

    2016-01-01

    Inhibition-stabilized networks (ISNs) are neural architectures with strong positive feedback among pyramidal neurons balanced by strong negative feedback from inhibitory interneurons, a circuit element found in the hippocampus and the primary visual cortex. In their working regime, ISNs produce damped oscillations in the γ-range in response to inputs to the inhibitory population. In order to understand the properties of interconnected ISNs, we investigated periodic forcing of ISNs. We show that ISNs can be excited over a range of frequencies and derive properties of the resonance peaks. In particular, we studied the phase-locked solutions, the torus solutions, and the resonance peaks. Periodically forced ISNs respond with (possibly multistable) phase-locked activity, whereas networks with sustained intrinsic oscillations respond more dynamically to periodic inputs with tori. Hence, the dynamics are surprisingly rich, and phase effects alone do not adequately describe the network response. This strengthens the importance of phaseamplitude coupling as opposed to phase-phase coupling in providing multiple frequencies for multiplexing and routing information. PMID:26496044

  14. DETERMINATION THE PERMISSIBLE FORCES IN ASSESSING THE LIFT RESISTANT FACTOR OF FREIGHT CARS IN TRAINS

    Directory of Open Access Journals (Sweden)

    A. O. Shvets

    2016-02-01

    Full Text Available Purpose. In the analytical research are considered: 1 relationships between the longitudinal force acting on the car in the train; 2 lateral and vertical forces of interaction in the contact zone «wheel – rail»; 3 dynamic indicators of cars with the magnitude of the car lift resistance factor; 4 obtaining of the dependencies between them. Methodology. The study was conducted by an analytical method assessing the sustainability of the freight car when driving at different speeds on the straight and curved track sections. Findings. In the process of studying the motion of the train, in the investigation of transport events, as well as during the training on the simulator operator, to assess the actions of the driver, the values of the longitudinal forces in the inter car connections are used. To calculate the longitudinal compressive forces, acting on the car, in which car lift resistance factor will be equal to the allowable value (critical force. To assess the impact on the value of the longitudinal force speed, coefficients of the vertical and horizontal dynamics, as well as the wind load on the side surface of the car body are the results of calculations of motion of the empty gondola car, model № 12-532 curve radius of 250 m with a rise of 150 mm and a transverse run of body of car frame relative to the track axis of the guide section 50 mm. Originality. In this study, the technique of determining the longitudinal compressive force was shown, that is somewhat different from the standard. So, as well as assessing the impact on it the speed of rolling coefficients of vertical and horizontal dynamics and wind load on the side surface of the car body. Practical value. The authors developed proposals on the enhancement of existing methods for determining the value of the longitudinal compressive forces acting on the car in which the safety value of the car lift resistance factor will be equal to the allowable value. It will evaluate the

  15. Stabilizing and destabilizing forces in the nursing work environment: a qualitative study on turnover intention.

    Science.gov (United States)

    Choi, Sandy Pin-Pin; Pang, Samantha Mei-Che; Cheung, Kin; Wong, Thomas Kwok-Shing

    2011-10-01

    The nursing work environment, which provides the context of care delivery, has been gaining increasing attention in recent years. A growing body of evidence points to an inseparable link between attributes of the nursing work environment and nurse and patient outcomes. While most studies have adopted a survey design to examine the workforce and work environment issues, this study employed a phenomenological approach to provide empirical evidence regarding nurses' perceptions of their work and work environment. The aim of this study was to advance our understanding of the phenomenon of increasing nurse turnover through exploring frontline registered nurses' lived experiences of working in Hong Kong public hospitals. A modified version of Van Kaam's controlled explication method was adopted. Individual semi-structured interviews were conducted with 26 frontline nurses recruited from ten acute regional, district and non-acute public hospitals in Hong Kong. Their perspectives in regard to their work and work environment, such as workload, manpower demand and professional values, were extensively examined, and a hypothetical description relating the nursing work environment with nurses' turnover intention was posited. Contemplation of nurses' experiences revealed the vulnerable aspects of nursing work and six essential constituents of the nursing work environment, namely staffing level, work responsibility, management, co-worker relationships, job, and professional incentives. These essential constituents have contributed to two sets of forces, stabilizing and destabilizing forces, which originate from the attributes of the nursing work environment. Nurses viewed harmonious co-worker relationships, recognition and professional development as the crucial retaining factors. However, nurses working in an unfavorable environment were overwhelmed by destabilizing forces; they expressed frustration and demonstrated an intention to leave their work environment. The nursing

  16. Significant improvements in stability and reproducibility of atomic-scale atomic force microscopy in liquid

    International Nuclear Information System (INIS)

    Akrami, S M R; Nakayachi, H; Fukuma, T; Watanabe-Nakayama, T; Asakawa, H

    2014-01-01

    Recent advancement of dynamic-mode atomic force microscopy (AFM) for liquid-environment applications enabled atomic-scale studies on various interfacial phenomena. However, instabilities and poor reproducibility of the measurements often prevent systematic studies. To solve this problem, we have investigated the effect of various tip treatment methods for atomic-scale imaging and force measurements in liquid. The tested methods include Si coating, Ar plasma, Ar sputtering and UV/O 3 cleaning. We found that all the methods provide significant improvements in both the imaging and force measurements in spite of the tip transfer through the air. Among the methods, we found that the Si coating provides the best stability and reproducibility in the measurements. To understand the origin of the fouling resistance of the cleaned tip surface and the difference between the cleaning methods, we have investigated the tip surface properties by x-ray photoelectron spectroscopy and contact angle measurements. The results show that the contaminations adsorbed on the tip during the tip transfer through the air should desorb from the surface when it is immersed in aqueous solution due to the enhanced hydrophilicity by the tip treatments. The tip surface prepared by the Si coating is oxidized when it is immersed in aqueous solution. This creates local spots where stable hydration structures are formed. For the other methods, there is no active mechanism to create such local hydration sites. Thus, the hydration structure formed under the tip apex is not necessarily stable. These results reveal the desirable tip properties for atomic-scale AFM measurements in liquid, which should serve as a guideline for further improvements of the tip treatment methods. (paper)

  17. A theoretical study of the influence of superconductor and magnet dimensions on the levitation force and stability of maglev systems

    International Nuclear Information System (INIS)

    Del-Valle, Nuria; Sanchez, Alvaro; Navau, Carles; Chen Duxing

    2008-01-01

    The levitation force and stability of superconducting levitation devices are strongly dependent on both the geometry and dimensions of the components and the cooling process of the superconductor. In this work we study these effects in levitating systems consisting of an infinitely long superconductor and a guideway of different arrangements of infinitely long parallel permanent magnets. Using a model based on the critical-state model and a magnetic-energy minimization procedure, taking into account the demagnetization fields, we analyze the influence of parameters of the system such as the width and height of the superconductor and those of the permanent magnets on the levitation force and stability for two different cooling processes, field cooling and zero-field cooling. The theoretical predictions are compared with existing experimental data. From the results obtained, we provide some general trends on how the dimensions of the components of maglev systems could be chosen to improve both the levitation force and the stability.

  18. A theoretical study of the influence of superconductor and magnet dimensions on the levitation force and stability of maglev systems

    Energy Technology Data Exchange (ETDEWEB)

    Del-Valle, Nuria; Sanchez, Alvaro; Navau, Carles; Chen Duxing [Grup d' Electromagnetisme, Departament de Fisica, Universitat Autonoma Barcelona, 08193 Bellaterra (Barcelona), Catalonia (Spain)

    2008-12-15

    The levitation force and stability of superconducting levitation devices are strongly dependent on both the geometry and dimensions of the components and the cooling process of the superconductor. In this work we study these effects in levitating systems consisting of an infinitely long superconductor and a guideway of different arrangements of infinitely long parallel permanent magnets. Using a model based on the critical-state model and a magnetic-energy minimization procedure, taking into account the demagnetization fields, we analyze the influence of parameters of the system such as the width and height of the superconductor and those of the permanent magnets on the levitation force and stability for two different cooling processes, field cooling and zero-field cooling. The theoretical predictions are compared with existing experimental data. From the results obtained, we provide some general trends on how the dimensions of the components of maglev systems could be chosen to improve both the levitation force and the stability.

  19. SOME ASPECTS OF THE DEFINITION OF EMPTY CARS STABILITY FROM SQUEEZING THEIR LONGITUDINAL FORCES IN THE FREIGHT TRAIN

    Directory of Open Access Journals (Sweden)

    A. O. Shvets

    2015-06-01

    Full Text Available Purpose. Despite of the implementation various programs to improve the safety of train traffic problem of reducing gatherings rolling stock off the rails is still relevant. The study aims to clarify the existing method of determining the factor of stability from the tire longitudinal forces to ensure the sustainability of cars with increasing speeds of the rolling stock. Methodology. Research was conducted by the method of mathematical modeling of loading freight car when driving at different speeds on straight and curved track sections. Findings. Analysis of the results shows that, for all selected freight cars for the calculation, the value of the safety factor by squeezing is smaller than the formulas of Standards. Corrections made to the formula for determining the safety factor by squeezing longitudinal forces, would achieve: 1 a higher safety factor of lightweight cars, excluding them squeezing longitudinal forces in the entire range of speeds of freight trains; 2 to develop and implement measures to prevent squeezing of cars in the entire range of motion; 3 to determine the degree of stability of the empty car in the head, middle and tail laden trains; 4 to offer optimal scheme of mixed trains formation. Originality. The analysis of existing methods for determining stability coefficient cars in freight trains from squeezing their longitudinal forces is presented in studies. Proposals are developed for the refinement of the design phase, construction and operation. Practical value. This study clarifies the existing method of determining the safety factor of stability from the squeezing longitudinal forces, as well as the influence on the magnitude of the coefficient of speed of movement of the rolling stock. Developed proposals for the refinement of existing methods for determining stability coefficient of longitudinal forces squeezing cars in a train, can reduce the number of retirements cars derailed by taking into account in the

  20. A novel vehicle dynamics stability control algorithm based on the hierarchical strategy with constrain of nonlinear tyre forces

    Science.gov (United States)

    Li, Liang; Jia, Gang; Chen, Jie; Zhu, Hongjun; Cao, Dongpu; Song, Jian

    2015-08-01

    Direct yaw moment control (DYC), which differentially brakes the wheels to produce a yaw moment for the vehicle stability in a steering process, is an important part of electric stability control system. In this field, most control methods utilise the active brake pressure with a feedback controller to adjust the braked wheel. However, the method might lead to a control delay or overshoot because of the lack of a quantitative project relationship between target values from the upper stability controller to the lower pressure controller. Meanwhile, the stability controller usually ignores the implementing ability of the tyre forces, which might be restrained by the combined-slip dynamics of the tyre. Therefore, a novel control algorithm of DYC based on the hierarchical control strategy is brought forward in this paper. As for the upper controller, a correctional linear quadratic regulator, which not only contains feedback control but also contains feed forward control, is introduced to deduce the object of the stability yaw moment in order to guarantee the yaw rate and side-slip angle stability. As for the medium and lower controller, the quantitative relationship between the vehicle stability object and the target tyre forces of controlled wheels is proposed to achieve smooth control performance based on a combined-slip tyre model. The simulations with the hardware-in-the-loop platform validate that the proposed algorithm can improve the stability of the vehicle effectively.

  1. Synchrophasor-Based Online Coherency Identification in Voltage Stability Assessment

    Directory of Open Access Journals (Sweden)

    ADEWOLE, A. C.

    2015-11-01

    Full Text Available This paper presents and investigates a new measurement-based approach in the identification of coherent groups in load buses and synchronous generators for voltage stability assessment application in large interconnected power systems. A hybrid Calinski-Harabasz criterion and k-means clustering algorithm is developed for the determination of the cluster groups in the system. The proposed method is successfully validated by using the New England 39-bus test system. Also, the performance of the voltage stability assessment algorithm using wide area synchrophasor measurements from the key synchronous generator in each respective cluster was tested online for the prediction of the system's margin to voltage collapse using a testbed comprising of a Programmable Logic Controller (PLC in a hardware-in-the-loop configuration with the Real-Time Digital Simulator (RTDS and Phasor Measurement Units (PMUs.

  2. Force-Velocity-Power Assessment in Semiprofessional Rugby Union Players.

    Science.gov (United States)

    McMaster, Daniel T; Gill, Nicholas D; Cronin, John B; McGuigan, Michael R

    2016-04-01

    There is a constant and necessary evolution of training and assessment methods in the elite contact sports; as is required to continually improve the physical qualities of these respective athletes to match the growing sport and position-specific performance demands. Our aim was to examine the differences between ballistic upper body performance profiles and maximum upper body strength of elite rugby union forwards and backs. Twenty semiprofessional male rugby union players (age = 21.1 ± 3.0 years; mass = 94.9 ± 9.7 kg) were assessed for maximum bench press strength (1RM bench press = 121.3 ± 21.8 kg) and maximum throw power (Pmax), force (Fmax), and velocity (V[Combining Dot Above]max) from an incremental relative load testing protocol (15, 30, 45, 60, and 75% 1RM). Player rankings were also included to identify individual strength and weaknesses. The forwards were moderately stronger (effect size [ES] = 0.96; p = 0.01), produced significantly greater Fmax (ES = 1.17-1.41; p = 0.01) and were more powerful (ES = 0.57-0.64; p 0.15). There were inherent differences in strength and Fmax between the forwards and backs most likely because of the physical demands of these respective positions. Improvements in upper body strength may in turn improve ballistic force and power production, but not necessarily velocity capabilities. From the Fmax and V[Combining Dot Above]max observations, the forwards seem to be more force dominant and the backs more velocity dominant. Pmax, Fmax, and V[Combining Dot Above]max may be used to highlight proficient and deficient areas in ballistic upper body performance; the individual rankings could be further used to identify and possibly rectify individual deficiencies.

  3. TWTF project criticality task force final review and assessment

    International Nuclear Information System (INIS)

    McKinley, K.B.; Cannon, J.W.; Wheeler, F.J.; Worle, H.A.

    1980-11-01

    The Transuranic Waste Treatment Facility (TWTF) is being developed to process transuranic waste, stored and buried at the Idaho National Engineering Laboratory, into a chemically inert, physically stable basalt-like residue acceptable at a federal repository. A task force was assembled by the TWTF Project Division to review and assess all aspects of criticality safety for the TWTF. This document presents the final review, assessments, and recommendations of this task force. The following conclusions were made: Additional criticality studies are needed for the entire envelope of feed compositions and temperature effects. Safe operating k/sub eff/'s need to be determined for process components. Criticality analyses validation experiments may also be required. SRP neutron interrogation should be replaced by DDT neutron interrogation. Accuracy studies need to be performed for the proposed assaying techniques. Time-correlated neutron monitoring needs to be mocked up for process components to prove feasibility and determine accuracy. The criticality control techniques developed for the TWTF conceptual design are in compliance with ERDAM 0530, including the Double Contingency Rule. Detailed procedures and controls need to be developed

  4. Eielson Air Force Base OU-1 baseline risk assessment

    International Nuclear Information System (INIS)

    Jarvis, M.T.; Jarvis, T.T.; Van Houten, N.C.; Lewis, R.E.

    1993-09-01

    This Baseline Risk Assessment report is the second volume in a set of three volumes for operable Unit 1 (OU-1). The companion documents contain the Remedial Investigation and the Feasibility Study. Operable Unit 1 (OU-1) is one of several groups of hazardous waste sites located at Eielson Air Force Base (AFB) near Fairbanks, Alaska. The operable units at Eielson are typically characterized by petroleum, oil, lubricant/solvent contamination, and by the presence of organics floating at the water table. In 1989 and 1990, firms under contract to the Air Force conducted field studies to gather information about the extent of chemical contamination in soil, groundwater, and soil air pore space (soil gas) at the site. This report documents the results of a baseline risk assessment, which uses the 1989 and 1991 site characterization database to quantify the potential human health risk associated with past Base industrial activities in the vicinity of OU-1. Background data collected in 1992 were also used in the preparation of this report

  5. Quality assessment of digested sludges produced by advanced stabilization processes.

    Science.gov (United States)

    Braguglia, C M; Coors, A; Gallipoli, A; Gianico, A; Guillon, E; Kunkel, U; Mascolo, G; Richter, E; Ternes, T A; Tomei, M C; Mininni, G

    2015-05-01

    The European Union (EU) Project Routes aimed to discover new routes in sludge stabilization treatments leading to high-quality digested sludge, suitable for land application. In order to investigate the impact of different enhanced sludge stabilization processes such as (a) thermophilic digestion integrated with thermal hydrolysis pretreatment (TT), (b) sonication before mesophilic/thermophilic digestion (UMT), and (c) sequential anaerobic/aerobic digestion (AA) on digested sludge quality, a broad class of conventional and emerging organic micropollutants as well as ecotoxicity was analyzed, extending the assessment beyond the parameters typically considered (i.e., stability index and heavy metals). The stability index was improved by adding aerobic posttreatment or by operating dual-stage process but not by pretreatment integration. Filterability was worsened by thermophilic digestion, either alone (TT) or coupled with mesophilic digestion (UMT). The concentrations of heavy metals, present in ranking order Zn > Cu > Pb > Cr ~ Ni > Cd > Hg, were always below the current legal requirements for use on land and were not removed during the processes. Removals of conventional and emerging organic pollutants were greatly enhanced by performing double-stage digestion (UMT and AA treatment) compared to a single-stage process as TT; the same trend was found as regards toxicity reduction. Overall, all the digested sludges exhibited toxicity to the soil bacterium Arthrobacter globiformis at concentrations about factor 100 higher than the usual application rate of sludge to soil in Europe. For earthworms, a safety margin of factor 30 was generally achieved for all the digested samples.

  6. The effect of the virtual mass force term on the stability of transient two-phase flow analysis

    International Nuclear Information System (INIS)

    Watanabe, Tadashi; Hirano, Masashi; Tanabe, Fumiya

    1989-08-01

    The effect of the virtual mass force term on the stability of transient two-phase flow analysis is studied. The objective form of the virtual mass acceleration is used. The virtual mass coefficient is determined from the stability condition of basic equations against infinitesimal high wave-number perturbations. The parameter is chosen so that a reasonable agreement between the analytical and experimental sound speed in two-phase flows can be obtained. A one-dimensional sedimentation problem is simulated by the MINCS code which is a tool for transient two-phase flow analysis. The stability analysis is performed for the numerical procedure. It is shown that calculated results are stabilized so long as the virtual mass coefficient satisfies the stability condition of differential equations. (author)

  7. Assessing slope stability in unplanned settlements in developing countries.

    Science.gov (United States)

    Anderson, Malcolm G; Holcombe, Liz; Renaud, Jean-Philippe

    2007-10-01

    Unplanned housing in developing countries is often located on steep slopes. Frequently no building code is enforced for such housing and mains water is provided with no drainage provision. Both of these factors can be particularly significant in terms of landslide risk if, as is so often the case, such slopes lack any planned drainage provision. There is thus a need to develop a model that facilitates the assessment of slope stability in an holistic context, incorporating a wide range of factors (including surface cover, soil water topographic convergence, slope loading and point source water leakage) in order that appropriate advice can be given as to the general controls on slope stability in such circumstances. This paper outlines a model configured for this specific purpose and describes an application to a site in St. Lucia, West Indies, where there is active slope movement in an unplanned housing development on relatively steep topography. The model findings are in accord with the nature of the current failure at the site, provide guidance as to the significance of slope drainage and correspond to inferences drawn from an application of resistance envelope methods to the site. In being able to scenario test a uniquely wide range of combinations of factors, the model structure is shown to be highly valuable in assessing dominant slope stability process controls in such complex environments.

  8. Electromechanical impedance method to assess dental implant stability

    International Nuclear Information System (INIS)

    Tabrizi, Aydin; Rizzo, Piervincenzo; Ochs, Mark W

    2012-01-01

    The stability of a dental implant is a prerequisite for supporting a load-bearing prosthesis and establishment of a functional bone–implant system. Reliable and noninvasive methods able to assess the bone interface of dental and orthopedic implants (osseointegration) are increasingly demanded for clinical diagnosis and direct prognosis. In this paper, we propose the electromechanical impedance method as a novel approach for the assessment of dental implant stability. Nobel Biocare ® implants with a size of 4.3 mm diameter ×13 mm length were placed inside bovine bones that were then immersed in a solution of nitric acid to allow material degradation. The degradation simulated the inverse process of bone healing. The implant–bone systems were monitored by bonding a piezoceramic transducer (PZT) to the implants’ abutment and measuring the admittance of the PZT over time. It was found that the PZT’s admittance and the statistical features associated with its analysis are sensitive to the degradation of the bones and can be correlated to the loss of calcium measured by means of the atomic absorption spectroscopy method. The present study shows promising results and may pave the road towards an innovative approach for the noninvasive monitoring of dental implant stability and integrity. (paper)

  9. Assessing the quality of force feedback in soft tissue simulation.

    Science.gov (United States)

    Basafa, Ehsan; Sefati, Shahin; Okamura, Allison M

    2011-01-01

    Many types of deformable models have been proposed for simulation of soft tissue in surgical simulators, but their realism in comparison to actual tissue is rarely assessed. In this paper, a nonlinear mass-spring model is used for realtime simulation of deformable soft tissues and providing force feedback to a human operator. Force-deformation curves of real soft tissue samples were obtained experimentally, and the model was tuned accordingly. To test the realism of the model, we conducted two human-user experiments involving palpation with a rigid probe. First, in a discrimination test, users identified the correct category of real and virtual tissue better than chance, and tended to identify the tissues as real more often than virtual. Second, users identified real and virtual tissues by name, after training on only real tissues. The sorting accuracy was the same for both real and virtual tissues. These results indicate that, despite model limitations, the simulation could convey the feel of touching real tissues. This evaluation approach could be used to compare and validate various soft-tissue simulators.

  10. Comparative study of probabilistic methodologies for small signal stability assessment

    Energy Technology Data Exchange (ETDEWEB)

    Rueda, J.L.; Colome, D.G. [Universidad Nacional de San Juan (IEE-UNSJ), San Juan (Argentina). Inst. de Energia Electrica], Emails: joseluisrt@iee.unsj.edu.ar, colome@iee.unsj.edu.ar

    2009-07-01

    Traditional deterministic approaches for small signal stability assessment (SSSA) are unable to properly reflect the existing uncertainties in real power systems. Hence, the probabilistic analysis of small signal stability (SSS) is attracting more attention by power system engineers. This paper discusses and compares two probabilistic methodologies for SSSA, which are based on the two point estimation method and the so-called Monte Carlo method, respectively. The comparisons are based on the results obtained for several power systems of different sizes and with different SSS performance. It is demonstrated that although with an analytical approach the amount of computation of probabilistic SSSA can be reduced, the different degrees of approximations that are adopted, lead to deceptive results. Conversely, Monte Carlo based probabilistic SSSA can be carried out with reasonable computational effort while holding satisfactory estimation precision. (author)

  11. Determination of equivalent mixing height and atmospheric stability assessment

    International Nuclear Information System (INIS)

    Simon, J.; Bulko, M.; Holy, K.

    2007-01-01

    Atmospheric stability is an indicator that reflects the intensity of boundary layer mixing processes. This feature of the atmosphere is especially important since it defines dispersive atmospheric conditions and provides information on how effectively the anthropogenic pollution will be transferred to the higher levels of the atmosphere. The assessment of atmospheric dispersiveness plays a crucial role in the protection of air quality and public health in big cities. The presented paper deals with determination of atmospheric stability via so called Equivalent Mixing Height (EMH) quantity using a radioactive noble gas 222 Rn. A method of deriving a link between 222 Rn activity concentration, eddy diffusion coefficient and EMH using fluid mechanics is also outlined in this work. (authors)

  12. Assessment of light stability of drugs in blood and plasma.

    Science.gov (United States)

    de Vries, Ronald; Diels, Luc; Dillen, Lieve; Sips, Luc; Van Roosbroek, Dirk; Verhaeghe, Tom; Timmerman, Philip

    2016-10-01

    A procedure was developed for the assessment of photochemical stability of drugs in blood and plasma under standardized conditions. The procedure avoids a variable outcome of photochemical stability experiments and tests relevant worst case conditions so that unnecessary light protection is avoided. Results/methodology: Blood and plasma were spiked with a mixture of drugs and incubated in a Suntest CPS(+), in the laboratory on the bench and near the window on a sunny summer day. The results were compared. No protection from light, limited protection from light and full protection from light are advised for drugs that are stable in plasma in the Suntest CPS(+) at 250 W/m(2) for at least 30 min, for 5-30 min and for <5 min, respectively.

  13. Force direction patterns promote whole body stability even in hip-flexed walking, but not upper body stability in human upright walking

    Science.gov (United States)

    Müller, Roy; Rode, Christian; Aminiaghdam, Soran; Vielemeyer, Johanna; Blickhan, Reinhard

    2017-11-01

    Directing the ground reaction forces to a focal point above the centre of mass of the whole body promotes whole body stability in human and animal gaits similar to a physical pendulum. Here we show that this is the case in human hip-flexed walking as well. For all upper body orientations (upright, 25°, 50°, maximum), the focal point was well above the centre of mass of the whole body, suggesting its general relevance for walking. Deviations of the forces' lines of action from the focal point increased with upper body inclination from 25 to 43 mm root mean square deviation (RMSD). With respect to the upper body in upright gait, the resulting force also passed near a focal point (17 mm RMSD between the net forces' lines of action and focal point), but this point was 18 cm below its centre of mass. While this behaviour mimics an unstable inverted pendulum, it leads to resulting torques of alternating sign in accordance with periodic upper body motion and probably provides for low metabolic cost of upright gait by keeping hip torques small. Stabilization of the upper body is a consequence of other mechanisms, e.g. hip reflexes or muscle preflexes.

  14. Vermicomposting of Food Waste: Assessing the Stability and Maturity

    Directory of Open Access Journals (Sweden)

    Monireh Majlessi

    2012-12-01

    Full Text Available The vermicompost using earthworms (Eisenia Fetida was produced from food waste and chemical parameters (EC, pH, carbon to nitrogen contents(C/N and germination bioassaywas examined in order to assess the stability and maturity indicators during the vermicomposting process. The seed used in the germination bioassay was cress.The ranges of EC,pH, C/N and germination index were 7.5-4.9 mS/cm, 5.6-7.53, 30.13-14.32% and 12.8- 58.4%, espectively. The germination index (GI value revealed that vermicompost rendered as moderate phytotoxic to cress seed.Pearson correlation coefficient was used to evaluate the relationship between the parameters. High statistically significant correlation coefficient was calculated between the GI value and EC in the vermicompost at the 99% confidence level.The C/N value showed that the vermicompost was stable. As a result of these observations, stability test alone, was not able to ensure high vermicompost quality. Therefore, it appears that determining vermicompost quality requires a simultaneous use of maturity and stability tests.

  15. Evaluation of methods to assess push/pull forces in a construction task

    NARCIS (Netherlands)

    Hoozemans, M J; Van Der Beek, Allard J.; Frings-Dresena, M H; Van der Molen, Henk F.

    2001-01-01

    The objective of the present study was to determine the validity of methods to assess push/pull forces exerted in a construction task. Forces assessed using a hand-held digital force gauge were compared to those obtained using a highly accurate measuring frame. No significant differences were found

  16. Assessment of Stability and Energy Dissipation Performances of an Antifer Layer Protected Caisson

    Directory of Open Access Journals (Sweden)

    M. Sedat Kabdaşlı

    2015-08-01

    Full Text Available The present study intends to assess the stability and energy dissipation performances of a breakwater configuration (APC protected by an antifer layer. For comparison, an ordinary caisson (OC, which was 5% wider and 10% heavier, was also investigated. Physical models were implemented and tested under regular and irregular waves; and resulting linear and angular displacements were directly measured via a photogrammetric method. Additionally, wave forces and resulting horizontal displacements were estimated both from recorded pressure data and from individual incident waves by modified Goda method. To calculate the horizontal displacement, the estimated wave force time series were directly double-integrated, whilst the theoretical method proposed by Shimosako et al. (1994 were used on the individual force values. Although OC was tested under shorter durations and had a more favorable superstructure in terms of resisting forces, the results indicated that APC was significantly more stable. Energy dissipation performance of the tested configurations were quantified in terms of spectral averaged and phase resolved reflection coefficients, whereas antifer damage ratio was measured on a block-count basis. Results indicated that the APC configuration had an enhanced performance of dissipating the wave energy; moreover, the dissipated energy directly links to antifer damage ratio.

  17. Methods to assess the stability of a bicycle rider system

    NARCIS (Netherlands)

    Cooke, A.G.; Bulsink, Vera Elisabeth; Beusenberg, Mark; Dubbeldam, Rosemary; Bonnema, Gerrit Maarten; Poelman, Wim; Koopman, Hubertus F.J.M.

    2012-01-01

    The SOFIE (Intelligent Assisted Bicycles) project wishes to create performance and design guidelines for mechatronic appliances which improve the stability of electric bicycles, so-called intelligent stability assist devices (IAD). To achieve this goal, a stability hypothesis, an advanced

  18. Environmental Assessment for the General Plan and Maintenance of Patrick Air Force Base, Florida

    Science.gov (United States)

    2005-05-01

    considered viable. P A F B G e n e r a l P l a n E A 2 Environmental Effects The General Plan EA evaluated the environmental impacts of...year cycle. The potential environmental effects were assessed for the following environmental resource areas: air quality, water quality, geology...ADP Area Development Plan AF Air Force AFB Air Force Base AFETR Air Force Eastern Test Range AFI Air Force Instruction AFMAN Air Force Manual

  19. Trunk response and stability in standing under sagittal-symmetric pull-push forces at different orientations, elevations and magnitudes.

    Science.gov (United States)

    El Ouaaid, Z; Shirazi-Adl, A; Plamondon, A

    2018-03-21

    To reduce lifting and associated low back injuries, manual material handling operations often involve pulling-pushing of carts at different weights, orientations, and heights. The loads on spine and risk of injury however need to be investigated. The aim of this study was to evaluate muscle forces, spinal loads and trunk stability in pull-push tasks in sagittal-symmetric, static upright standing posture. Three hand-held load magnitudes (80, 120 and 160 N) at four elevations (0, 20, 40 and 60 cm to the L5-S1) and 24 force directions covering all pull/push orientations were considered. For this purpose, a musculoskeletal finite element model with kinematics measured earlier were used. Results demonstrated that peak spinal forces occur under inclined pull (lift) at upper elevations but inclined push at the lowermost one. Minimal spinal loads, on the other hand, occurred at and around vertical pull directions. Overall, spinal forces closely followed variations in the net external moment of pull-push forces at the L5-S1. Local lumbar muscles were most active in pulls while global extensor muscles in lifts. The trunk stability margin decreased with load elevation except at and around horizontal push; it peaked under pulls and reached minimum at vertical lifts. It also increased with antagonist activity in muscles and intra-abdominal pressure. Results provide insight into the marked effects of variation in the load orientation and elevation on muscle forces, spinal loads and trunk stability and hence offer help in rehabilitation, performance enhancement training and design of safer workplaces. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Effects of lorentz force on flow fields of free burning arc and wall stabilized non-transferred arc

    International Nuclear Information System (INIS)

    Peng Yi; Huang Heji; Pan Wenxia

    2013-01-01

    The flow fields of two typical DC plasma arcs, namely the transferred free burning arc and the non-transferred arc were simulated by solving hydrodynamic equations and electromagnetic equations. The effects of the Lorentz force on the characteristics of the flow fields of these two typical DC plasma arcs were estimated. Results show that in the case of the free burning arc, the Lorentz force due to the current self-induced magnetic field has significant impact on the flow fields, as the self-induced magnetic compression is the main arc constraint mechanism. However, in the case of the non-transferred arc generated in a torch with long and narrow inter-electrode inserts and an abruptly expanded anode, the Lorentz force has limited impact on the flow fields of the plasma especially at the downstream of the inter-electrode inserts, compared with the strong wall constraints and relatively high aerodynamic force. This is because the ratio of the electromagnetic force to the aerodynamic force is only about 0.01 in this region. When the main consideration is outlet parameters of the wall stabilized non-transferred DC arc plasma generator, in order to improve the efficiency of the numerical simulation program, the Lorentz force could be neglected in the non-transferred arc in some cases. (authors)

  1. Boundary layer stability on a yawed spinning body of revolution and its effect on the magnus force and moment

    Science.gov (United States)

    Jacobson, I. D.; Morton, J. B.

    1972-01-01

    The parameters are established which are important to the stability of a boundary layer flow over a yawed spinning cylinder in a uniform stream. It is shown that transition occurs asymmetrically in general and this asymmetry can be important for the prediction of aerodynamic forces and moments (e.g., the Magnus effect). Instability of the steady-state boundary layer flow is determined using small disturbance theory. Although the approach is strictly valid only for the calculation of the conditions for stability in the small, experimental data indicate that in many problems, it provides a good estimate for the transition to turbulence.

  2. Environmental Assessment for Proposed Security Forces Operations Facility, Buckley Air Force Base, Colorado

    National Research Council Canada - National Science Library

    Meyer, Elizabeth; Myklebust, Jessica; Denier, James; Christner, Jennifer; Fontaine, Kathyrn

    2006-01-01

    The United States Air Force (USAF) has prepared this EA in accordance with the National Environmental Policy Act to evaluate the potential environmental and social impacts from the construction and operation of the proposed SFOF...

  3. Atomic force microscopy and force spectroscopy on the assessment of protein folding and functionality.

    Science.gov (United States)

    Carvalho, Filomena A; Martins, Ivo C; Santos, Nuno C

    2013-03-01

    Atomic force microscopy (AFM) applied to biological systems can, besides generating high-quality and well-resolved images, be employed to study protein folding via AFM-based force spectroscopy. This approach allowed remarkable advances in the measurement of inter- and intramolecular interaction forces with piconewton resolution. The detection of specific interaction forces between molecules based on the AFM sensitivity and the manipulation of individual molecules greatly advanced the understanding of intra-protein and protein-ligand interactions. Apart from the academic interest in the resolution of basic scientific questions, this technique has also key importance on the clarification of several biological questions of immediate biomedical relevance. Force spectroscopy is an especially appropriate technique for "mechanical proteins" that can provide crucial information on single protein molecules and/or domains. Importantly, it also has the potential of combining in a single experiment spatial and kinetic measurements. Here, the main principles of this methodology are described, after which the ability to measure interactions at the single-molecule level is discussed, in the context of relevant protein-folding examples. We intend to demonstrate the potential of AFM-based force spectroscopy in the study of protein folding, especially since this technique is able to circumvent some of the difficulties typically encountered in classical thermal/chemical denaturation studies. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Testing of Method for Assessing of Room Thermal Stability

    Directory of Open Access Journals (Sweden)

    Charvátová Hana

    2017-01-01

    Full Text Available The paper presents the interim results of our research on the developing methodological procedure which could be used for assessment of a thermal stability of buildings with regards to its thermal accumulative parameters. The principle of testing is based on a combination of computer simulation of cooled room model developed in COMSOL Multiphysics software and on theoretical calculations with respect to compliance with valid European and Czech technical standards used in building industry and architecture under conditions obtained by real measurement for the room to be tested. The presented example shows the effect of the heataccumulation properties of the outside wall insulation materials on the course of the cooling room for winter conditions.

  5. What are the barriers to trying to reach, and evaluate the impact of working with, Forces Families? Assessing the effectiveness of Reading Force, a programme to promote shared reading within the Forces community

    OpenAIRE

    Baverstock, Alison

    2016-01-01

    What are the barriers to trying to reach, and evaluate the impact of working with, Forces Families? Assessing the effectiveness of Reading Force, a programme to promote shared reading within the Forces community

  6. Forelimb and hindlimb ground reaction forces of walking cats: Assessment and comparison with walking dogs

    NARCIS (Netherlands)

    Corbee, R.J.; Maas, H.; Doornenbal, A; Hazewinkel, H.A.W.

    2014-01-01

    The primary aim of this study was to assess the potential of force plate analysis for describing the stride cycle of the cat. The secondary aim was to define differences in feline and canine locomotion based on force plate characteristics. Ground reaction forces of 24 healthy cats were measured and

  7. The Combined Arms Maneuver-Force and the Stability and Support-Force: A Dual Force Concept to Meet the Challenges of Future Operations

    Science.gov (United States)

    2013-06-13

    Horizons” in El Salvador , the Dominican Republic, and Haiti. A critical part of these missions was the medical readiness training exercises...Sudan, rescued flood victims in Bangladesh, rushed pharmaceuticals to earthquake sites, and delivered medical teams to hundreds of major and minor...allowing rapid response to unforeseen crises. This includes sending forces to assist in the disaster relief operations after the October 2005 earthquake

  8. Capital Improvement Program Environmental Assessment, Dyess Air Force Base, Texas

    Science.gov (United States)

    2010-09-01

    Counsel • Air Force Office of Special Investigations • Air Force Audit Agency • Boeing Aerospace Operations Inc . • Defense Security Service...this corresponds to a factor of 10 in relative sound energy (Bolt, Beranek, and Meuman, Inc . 1973). Table 4-1 shows the dBA scale of commons...configuration for the B-47. Intact -Interior shop upgraded for Nike Hercules in 1961. 5020 Field Maintenance Hangar Large Aircraft Maintenance Dock

  9. The Self-esteem Stability Scale (SESS) for Cross-Sectional Direct Assessment of Self-esteem Stability.

    Science.gov (United States)

    Altmann, Tobias; Roth, Marcus

    2018-01-01

    Self-esteem stability describes fluctuations in the level of self-esteem experienced by individuals over a brief period of time. In recent decades, self-esteem stability has repeatedly been shown to be an important variable affecting psychological functioning. However, measures of self-esteem stability are few and lacking in validity. In this paper, we present the Self-Esteem Stability Scale (SESS), a unidimensional and very brief scale to directly assess self-esteem stability. In four studies (total N = 826), we describe the development of the SESS and present evidence for its validity with respect to individual outcomes (life satisfaction, neuroticism, and vulnerable narcissism) and dyadic outcomes (relationship satisfaction in self- and partner ratings) through direct comparisons with existing measures. The new SESS proved to be a stronger predictor than the existing scales and had incremental validity over and above self-esteem level. The results also showed that all cross-sectional measures of self-esteem stability were only moderately associated with variability in self-esteem levels assessed longitudinally with multiple administrations of the Rosenberg Self-Esteem Scale. We discuss this validity issue, arguing that direct and indirect assessment approaches measure relevant, yet different aspects of self-esteem stability.

  10. The Self-esteem Stability Scale (SESS for Cross-Sectional Direct Assessment of Self-esteem Stability

    Directory of Open Access Journals (Sweden)

    Tobias Altmann

    2018-02-01

    Full Text Available Self-esteem stability describes fluctuations in the level of self-esteem experienced by individuals over a brief period of time. In recent decades, self-esteem stability has repeatedly been shown to be an important variable affecting psychological functioning. However, measures of self-esteem stability are few and lacking in validity. In this paper, we present the Self-Esteem Stability Scale (SESS, a unidimensional and very brief scale to directly assess self-esteem stability. In four studies (total N = 826, we describe the development of the SESS and present evidence for its validity with respect to individual outcomes (life satisfaction, neuroticism, and vulnerable narcissism and dyadic outcomes (relationship satisfaction in self- and partner ratings through direct comparisons with existing measures. The new SESS proved to be a stronger predictor than the existing scales and had incremental validity over and above self-esteem level. The results also showed that all cross-sectional measures of self-esteem stability were only moderately associated with variability in self-esteem levels assessed longitudinally with multiple administrations of the Rosenberg Self-Esteem Scale. We discuss this validity issue, arguing that direct and indirect assessment approaches measure relevant, yet different aspects of self-esteem stability.

  11. The Self-esteem Stability Scale (SESS) for Cross-Sectional Direct Assessment of Self-esteem Stability

    Science.gov (United States)

    Altmann, Tobias; Roth, Marcus

    2018-01-01

    Self-esteem stability describes fluctuations in the level of self-esteem experienced by individuals over a brief period of time. In recent decades, self-esteem stability has repeatedly been shown to be an important variable affecting psychological functioning. However, measures of self-esteem stability are few and lacking in validity. In this paper, we present the Self-Esteem Stability Scale (SESS), a unidimensional and very brief scale to directly assess self-esteem stability. In four studies (total N = 826), we describe the development of the SESS and present evidence for its validity with respect to individual outcomes (life satisfaction, neuroticism, and vulnerable narcissism) and dyadic outcomes (relationship satisfaction in self- and partner ratings) through direct comparisons with existing measures. The new SESS proved to be a stronger predictor than the existing scales and had incremental validity over and above self-esteem level. The results also showed that all cross-sectional measures of self-esteem stability were only moderately associated with variability in self-esteem levels assessed longitudinally with multiple administrations of the Rosenberg Self-Esteem Scale. We discuss this validity issue, arguing that direct and indirect assessment approaches measure relevant, yet different aspects of self-esteem stability. PMID:29487551

  12. Impact of Model Detail of Synchronous Machines on Real-time Transient Stability Assessment

    DEFF Research Database (Denmark)

    Weckesser, Johannes Tilman Gabriel; Jóhannsson, Hjörtur; Østergaard, Jacob

    2013-01-01

    In this paper, it is investigated how detailed the model of a synchronous machine needs to be in order to assess transient stability using a Single Machine Equivalent (SIME). The results will show how the stability mechanism and the stability assessment are affected by the model detail. In order...... of the machine models is varied. Analyses of the results suggest that a 4th-order model may be sufficient to represent synchronous machines in transient stability studies....

  13. ASSESSING THE GOVERNANCE FOR COMMODITY PRICE STABILIZATION - A RETROSPECTIVE LOOK

    Directory of Open Access Journals (Sweden)

    Pop Larisa Nicoleta

    2015-07-01

    Full Text Available The volatility of commodity prices has become once again a matter of profound and controversial debates for both political and academic spheres worldwide in the framework of the global economy severely distressed by the recent economic turbulences. Although commodity markets were already notorious for their price instability, the events the world economy experienced in the years 2000s offered new connotations to this phenomenon. In the first decade of this millennium, the commodity markets have struggled with high volatility, with prices reaching historical peaks just to crash dramatically some months later and very soon to restart their rise. The significant increase in volatility generated many debates about its triggering factors, the implications in terms of risk exposure of economic actors, but also the need for reconfiguring regulatory policy frameworks. The quest for the most appropriate means to deal with commodity price turbulences has known different stages over the years. Decision makers worldwide have sought alternatives, formulated and tested various mechanisms whose central aim was to mitigate price fluctuations. Governments formulate and implement consistent regulatory policies whose international coordination is a ‘sine qua non’ condition for stabilizing these markets. However, the turbulences on commodity markets often generate policy responses that sometimes exacerbate rather than mitigate the price instability. The purpose of this paper is to assess the subject of governance regarding commodity price stabilization, offering a retrospective look at the mechanisms implemented over the years, with a central focus on the International Commodity Agreements – instruments through which in the previous decades the producer and consumer governments worldwide pursued price stabilization for some key commodities like sugar, coffee, cocoa, tin and natural rubber. After analyzing the effectiveness of the International Agreements and

  14. Assessment of Submarine Slope Stability on the Continental Margin off SW Taiwan

    Science.gov (United States)

    Hsu, Huai-Houh; Dong, Jia-Jyun; Cheng, Win-Bin; Su, Chih-Chieh

    2017-04-01

    The abundant gas hydrate reservoirs are distributed in the southwest (SW) off Taiwan. To explore this new energy, geological methods were systematically used and mainly emphasized on the storage potential evaluation. On the other hand, the correlation between gas hydrate dissociation and submarine slope stability is also an important issue. In this study, three submarine profiles on the active and passive continental margin were selected and assessed their slope stabilities by considering two influence factors (seismic forces and number of sedimentary layers). The gravity corers obtained from these three sites (Xiaoliuqiu, Yuan-An Ridge, and Pointer Ridge) to conduct soil laboratory tests. The physical property tests and isotropically consolidated undrained (CIU) triaxial tests were carried out to establish reference properties and shear strength parameters. Before the stability analysis is performed, it is also necessary to construct the seabed profile. For each submarine profile, data from P-waves and from S-waves generated by P-S conversion on reflection from airgun shots recorded along one line of ocean bottom seismometers were used to construct 2-D velocity sections. The seabed strata could be simplified to be only one sedimentary layer or to be multilayer in accordance with the velocity structure profile. Results show the safety factors (FS) of stability analysis are obviously different in considering the number of sedimentary layers, especially for a very thin layer of sediments on a steep slope. The simplified strata condition which treated all seabed strata as only one sedimentary layer might result in the FS lower than 1 and the slope was in an unstable state. On the contrary, the FS could be higher than 10 in a multilayer condition.

  15. Mechanical stability assessment of novel orthodontic mini-implant designs: Part 2.

    Science.gov (United States)

    Hong, Christine; Truong, Peter; Song, Ha Na; Wu, Benjamin M; Moon, Won

    2011-11-01

    To assess the mechanical stability of a newly revised orthodontic mini-implant design (N2) compared with a design introduced in Part 1 of the study (N1) and the most widely-used commercially-available design (CA). To evaluate the mean buccal bone thickness of maxillary and mandibular posterior teeth using cone-beam computed tomography (CBCT). From the CBCT scans of 20 patients, six tomographic cross-sections were generated for each tooth. Buccal bone thickness was measured from the most convex point on the bone to the root surface. CA (1.5 mm in diameter and 6 mm in length), N1, and N2 (shorter and narrower than N1) were inserted in simulated bone with cortical and trabecular bone layers. Mechanical stability was compared in vitro through torque and lateral displacement tests. The bone thickness ranged from 2.26 to 3.88 mm. Maximum insertion torque was decreased significantly in N2 compared to N1. However, force levels for all displacement distances and torque ratio were the highest in N2, followed by N1 and CA (α = .05). Both torque and lateral displacement tests highlighted the enhanced stability of N2 compared with CA. Design revisions to N1 effectively mitigated N1's high insertion torque and thus potentially reduced microdamage to the surrounding bone. The N2 design is promising as evidenced by enhanced stability and high mechanical efficiency. Moreover, N2 is not limited to placement in interradicular spaces and has the capacity to be placed in the buccal bone superficial to the root surface with diminished risk of endangering nearby anatomic structures during placement and treatment.

  16. Environmental Assessment for the Air Force Research Laboratory Security Fence Project, Edwards Air Force Base, California

    Science.gov (United States)

    2012-11-26

    Pleistocene/Early-Holocene Prehistory (12,000 to 7,000 BP). The Lake Mojave Period in the southwestern Great Basin comprises a regional manifestation...adaptive patterns with focal exploitation of such habitats (Tetra Tech 2010). Middle-Holocene Prehistory (8,000 to 4,000 BP). Succeeding Lake Mojave in the...Security Fence at Edwards Air Force Base, California Late Holocene Prehistory (4,000 to Contact). With return to more “favorable” environmental

  17. Conceptualization of preferential flow for hillslope stability assessment

    Science.gov (United States)

    Kukemilks, Karlis; Wagner, Jean-Frank; Saks, Tomas; Brunner, Philip

    2018-03-01

    This study uses two approaches to conceptualize preferential flow with the goal to investigate their influence on hillslope stability. Synthetic three-dimensional hydrogeological models using dual-permeability and discrete-fracture conceptualization were subsequently integrated into slope stability simulations. The slope stability simulations reveal significant differences in slope stability depending on the preferential flow conceptualization applied, despite similar small-scale hydrogeological responses of the system. This can be explained by a local-scale increase of pore-water pressures observed in the scenario with discrete fractures. The study illustrates the critical importance of correctly conceptualizing preferential flow for slope stability simulations. It further demonstrates that the combination of the latest generation of physically based hydrogeological models with slope stability simulations allows for improvement to current modeling approaches through more complex consideration of preferential flow paths.

  18. Applying programmatic risk assessment to nuclear materials stabilization R and D planning

    International Nuclear Information System (INIS)

    Kenley, C.R.; Brown-van Hoozer, S.A.

    1997-01-01

    A systems engineering approach to programmatic risk assessment, derived from the aerospace industry, was applied to various stabilization technologies to assess their relative maturity and availability for use in stabilizing nuclear materials. The assessment provided valuable information for trading off available technologies and identified the at-risk technologies that will require close tracking by the Department of Energy (DOE) to mitigate programmatic risks

  19. Summary of Independent Assessment of the Afghan National Security Forces

    Science.gov (United States)

    2014-02-01

    Afghan National Police (ANP), which are the Afghan Border Police ( ABP ), Afghan National Civil Order Police (ANCOP), Afghan Uniform Police (AUP...intentionally left blank 43 Acronyms AACP Afghan Anti-Crime Police AAF Afghan Air Force ABP Afghan Border Police ALP Afghan

  20. Final Nellis Air Force Base Capital Improvements Program Environmental Assessment

    Science.gov (United States)

    2013-08-01

    pathology, radiology, dietetic and nutritional medicine, medical benefits and information. The 99th Security Forces Squadron provides flight-line...parking lots RKMF070024 Construct Soccer Field Parking Lot Roads/parking lots RKMF110155 Construct Solar Lighting At Hospital Track Recreation

  1. Assessing fly ash treatment: remediation and stabilization of heavy metals.

    Science.gov (United States)

    Lima, A T; Ottosen, Lisbeth M; Ribeiro, Alexandra B

    2012-03-01

    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Assessing fly ash treatment: Remediation and stabilization of heavy metals

    KAUST Repository

    Lima, A.T.

    2010-12-17

    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete. © 2010 Elsevier Ltd.

  3. Environmental Assessment -- Test Area North pool stabilization project update

    International Nuclear Information System (INIS)

    1997-08-01

    The purpose of this Environmental Assessment (EA) is to update the ''Test Area North Pool Stabilization Project'' EA (DOE/EA-1050) and finding of no significant impact (FONSI) issued May 6, 1996. This update analyzes the environmental and health impacts of a drying process for the Three Mile Island (TMI) nuclear reactor core debris canisters now stored underwater in a facility on the Idaho National Engineering and Environmental Laboratory (INEEL). A drying process was analyzed in the predecision versions of the EA released in 1995 but that particular process was determined to be ineffective and dropped from the EA/FONSI issued May 6, 1996. A new drying process was subsequently developed and is analyzed in Section 2.1.2 of this document. As did the 1996 EA, this update analyzes the environmental and health impacts of removing various radioactive materials from underwater storage, dewatering these materials, constructing a new interim dry storage facility, and transporting and placing the materials into the new facility. Also, as did the 1996 EA, this EA analyzes the removal, treatment and disposal of water from the pool, and placement of the facility into a safe, standby condition. The entire action would take place within the boundaries of the INEEL. The materials are currently stored underwater in the Test Area North (TAN) building 607 pool, the new interim dry storage facility would be constructed at the Idaho Chemical Processing Plant (ICPP) which is about 25 miles south of TAN

  4. Draft environmental assessment -- Test Area North pool stabilization project update

    International Nuclear Information System (INIS)

    1997-06-01

    The purpose of this Environmental Assessment (EA) is to update the ''Test Area North Pool Stabilization Project'' EA (DOE/EA-1050) and finding of no significant impact (FONSI) issued May 6, 1996. This update analyzes the environmental and health impacts of a drying process for the Three Mile Island (TMI) nuclear reactor core debris canisters now stored underwater in a facility on the Idaho National Engineering and Environmental Laboratory (INEEL). A drying process was analyzed in the predecision versions of the EA released in 1995 but that particular process was determined to be ineffective and dropped form the Ea/FONSI issued May 6, 1996. The origin and nature of the TMI core debris and the proposed drying process are described and analyzed in detail in this EA. As did the 1996 EA, this update analyzes the environmental and health impacts of removing various radioactive materials from underwater storage, dewatering these materials, constructing a new interim dry storage facility, and transporting and placing the materials into the new facility. Also, as did the 1996 EA, this EA analyzes the removal, treatment and disposal of water from the pool, and placement of the facility into a safe, standby condition. The entire action would take place within the boundaries of the INEEL. The materials are currently stored underwater in the Test Area North (TAN) building 607 pool, the new interim dry storage facility would be constructed at the Idaho Chemical Processing Plant (ICPP) which is about 25 miles south of TAN

  5. Test Area North Pool Stabilization Project: Environmental assessment

    International Nuclear Information System (INIS)

    1996-05-01

    The Test Area North (TAN) Pool is located within the fenced TAN facility boundaries on the Idaho National Engineering Laboratory (INEL). The TAN pool stores 344 canisters of core debris from the March, 1979, Three Mile Island (TMI) Unit 2 reactor accident; fuel assemblies from Loss-of-Fluid Tests (LOFT); and Government-owned commercial fuel rods and assemblies. The LOFT and government owned commercial fuel rods and assemblies are hereafter referred to collectively as open-quotes commercial fuelsclose quotes except where distinction between the two is important to the analysis. DOE proposes to remove the canisters of TMI core debris and commercial fuels from the TAN Pool and transfer them to the Idaho Chemical Processing Plant (ICPP) for interim dry storage until an alternate storage location other than at the INEL, or a permanent federal spent nuclear fuel (SNF) repository is available. The TAN Pool would be drained and placed in an industrially and radiologically safe condition for refurbishment or eventual decommissioning. This environmental assessment (EA) identifies and evaluates environmental impacts associated with (1) constructing an Interim Storage System (ISS) at ICPP; (2) removing the TMI and commercial fuels from the pool and transporting them to ICPP for placement in an ISS, and (3) draining and stabilizing the TAN Pool. Miscellaneous hardware would be removed and decontaminated or disposed of in the INEL Radioactive Waste Management Complex (RWMC). This EA also describes the environmental consequences of the no action alternative

  6. Assessing fly ash treatment: Remediation and stabilization of heavy metals

    KAUST Repository

    Lima, A.T.; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

    2010-01-01

    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete. © 2010 Elsevier Ltd.

  7. Assessment of postural stability in overweight and obese middle-aged women

    Directory of Open Access Journals (Sweden)

    Zuzana Kováčiková

    2014-09-01

    Full Text Available Background: Obesity and overweight are defined as abnormal or excessive fat accumulation and are associated with balance disorders. Objective: To assess the postural stability in a natural stance in overweight and obese women based on center of pressure (CoP velocity in the anterior-posterior (AP and medial-lateral (ML directions. Methods: A total of 102 women categorized according to body mass index into normal weight, overweight and obese categories underwent a measurement of quiet standing with their eyes open (EO and with their eyes closed (EC. Postural stability was assessed with a force platform. The mean CoP velocity was evaluated in both directions. Results: In the AP direction under EO conditions, obese women swayed significantly faster than normal weight women (1.01 cm/s and 0.80 cm/s. In the ML direction, a higher CoP velocity was observed in normal weight women than in obese women (0.52 cm/s and 0.41 cm/s. Under EC conditions in the AP direction, obese women swayed significantly faster than normal weight women (1.29 cm/s and 0.97 cm/s. In the ML direction, a higher CoP velocity was observed in normal weight women than in obese women (0.65 cm/s and 0.48 cm/s. Conclusions: Results suggest a negative impact of obesity on postural stability in the AP direction. In the ML direction, obese women were more stable than normal weight women, probably due to enlargement of the support base in a natural stance.

  8. Stabilizing impacts in force-reflecting teleoperation using distance-to-impact estimates

    International Nuclear Information System (INIS)

    McAree, P.R.; Daniel, R.W.

    2000-01-01

    The level of force that can be stably reflected to the human operator in a force-reflecting teleoperator is constrained by the dynamics of impact between the slave arm and its environment. This paper models the underlying dynamics of impact and describes how the impact effects can be minimized using estimates of the distance between the slave and objects in its workspace. The approach is based on stochastic variational principles and seeks to limit the momentum of the slave arm at impact. Preliminary experimental results show that the approach allows extension of the range of frequencies that can be stably reflected to the human operator

  9. Stabilizing the long-time behavior of the forced Navier-Stokes and damped Euler systems by large mean flow

    Science.gov (United States)

    Cyranka, Jacek; Mucha, Piotr B.; Titi, Edriss S.; Zgliczyński, Piotr

    2018-04-01

    The paper studies the issue of stability of solutions to the forced Navier-Stokes and damped Euler systems in periodic boxes. It is shown that for large, but fixed, Grashoff (Reynolds) number the turbulent behavior of all Leray-Hopf weak solutions of the three-dimensional Navier-Stokes equations, in periodic box, is suppressed, when viewed in the right frame of reference, by large enough average flow of the initial data; a phenomenon that is similar in spirit to the Landau damping. Specifically, we consider an initial data which have large enough spatial average, then by means of the Galilean transformation, and thanks to the periodic boundary conditions, the large time independent forcing term changes into a highly oscillatory force; which then allows us to employ some averaging principles to establish our result. Moreover, we also show that under the action of fast oscillatory-in-time external forces all two-dimensional regular solutions of the Navier-Stokes and the damped Euler equations converge to a unique time-periodic solution.

  10. Initial assessment of the MHD stability of TMX-U

    International Nuclear Information System (INIS)

    Nexsen, W.E.

    1983-01-01

    In its operation to date TMX-U has reached values of beta which, for all except the hot electron beta, are close to the proposal values and has not encountered MHD stability problems. The hot electron beta values are presently limited by gyrotron output power and pulse length as well as ion confinement time. Further exploration of stability awaits full thermal barrier operation

  11. The Problems and Prospects of Rating Assessment of Political Stability

    Directory of Open Access Journals (Sweden)

    Ирина Анатольевна Белоусова

    2015-12-01

    Full Text Available The article is devoted to the analysis of principles of qualitative and quantitative approaches to measurement of political stability. The author gives a detailed analysis of the problems and prospects of ratings and indices as tools of political analysis and measurement of political stability.

  12. ASSESSING CLIMATE CHANGE IMPACTS ON THE STABILITY OF SMALL TIDAL INLETS: Part 2- DATA RICH ENVIRONMENTS.

    Science.gov (United States)

    Duong, Trang Minh; Ranasinghe, Roshanka; Thatcher, Marcus; Mahanama, Sarith; Wang, Zheng Bing; Dissanayake, Pushpa Kumara; Hemer, Mark; Luijendijk, Arjen; Bamunawala, Janaka; Roelvink, Dano; Walstra, Dirkjan

    2018-01-01

    Climate change (CC) is likely to affect the thousands of bar-built or barrier estuaries (here referred to as Small tidal inlets - STIs) around the world. Any such CC impacts on the stability of STIs, which governs the dynamics of STIs as well as that of the inlet-adjacent coastline, can result in significant socio-economic consequences due to the heavy human utilisation of these systems and their surrounds. This article demonstrates the application of a process based snap-shot modelling approach, using the coastal morphodynamic model Delft3D , to 3 case study sites representing the 3 main STI types; Permanently open, locationally stable inlets (Type 1), Permanently open, alongshore migrating inlets (Type 2) and Seasonally/Intermittently open, locationally stable inlets (Type 3). The 3 case study sites (Negombo lagoon - Type 1, Kalutara lagoon - Type 2, and Maha Oya river - Type 3) are all located along the southwest coast of Sri Lanka. After successful hydrodynamic and morphodynamic model validation at the 3 case study sites, CC impact assessment are undertaken for a high end greenhouse gas emission scenario. Future CC modified wave and riverflow conditions are derived from a regional scale application of spectral wave models (WaveWatch III and SWAN) and catchment scale applications of a hydrologic model (CLSM) respectively, both of which are forced with IPCC Global Climate Model output dynamically downscaled to ~ 50 km resolution over the study area with the stretched grid Conformal Cubic Atmospheric Model CCAM. Results show that while all 3 case study STIs will experience significant CC driven variations in their level of stability, none of them will change Type by the year 2100. Specifically, the level of stability of the Type 1 inlet will decrease from 'Good' to 'Fair to poor' by 2100, while the level of (locational) stability of the Type 2 inlet will also decrease with a doubling of the annual migration distance. Conversely, the stability of the Type 3 inlet

  13. The Automated Assessment of Postural Stability: Balance Detection Algorithm.

    Science.gov (United States)

    Napoli, Alessandro; Glass, Stephen M; Tucker, Carole; Obeid, Iyad

    2017-12-01

    Impaired balance is a common indicator of mild traumatic brain injury, concussion and musculoskeletal injury. Given the clinical relevance of such injuries, especially in military settings, it is paramount to develop more accurate and reliable on-field evaluation tools. This work presents the design and implementation of the automated assessment of postural stability (AAPS) system, for on-field evaluations following concussion. The AAPS is a computer system, based on inexpensive off-the-shelf components and custom software, that aims to automatically and reliably evaluate balance deficits, by replicating a known on-field clinical test, namely, the Balance Error Scoring System (BESS). The AAPS main innovation is its balance error detection algorithm that has been designed to acquire data from a Microsoft Kinect ® sensor and convert them into clinically-relevant BESS scores, using the same detection criteria defined by the original BESS test. In order to assess the AAPS balance evaluation capability, a total of 15 healthy subjects (7 male, 8 female) were required to perform the BESS test, while simultaneously being tracked by a Kinect 2.0 sensor and a professional-grade motion capture system (Qualisys AB, Gothenburg, Sweden). High definition videos with BESS trials were scored off-line by three experienced observers for reference scores. AAPS performance was assessed by comparing the AAPS automated scores to those derived by three experienced observers. Our results show that the AAPS error detection algorithm presented here can accurately and precisely detect balance deficits with performance levels that are comparable to those of experienced medical personnel. Specifically, agreement levels between the AAPS algorithm and the human average BESS scores ranging between 87.9% (single-leg on foam) and 99.8% (double-leg on firm ground) were detected. Moreover, statistically significant differences in balance scores were not detected by an ANOVA test with alpha equal to 0

  14. 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.

  15. Stabilization of thin liquid films by repulsive van der waals force

    KAUST Repository

    Li, Erqiang; Vakarelski, Ivan Uriev; Chan, Derek Y C; Thoroddsen, Sigurdur T

    2014-01-01

    Using high-speed video recording of bubble rise experiments, we study the stability of thin liquid films trapped between a rising bubble and a surfactant-free liquid-liquid meniscus interface. Using different combinations of nonpolar oils and water

  16. Biomechanical Effects of Posterior Condylar Offset and Posterior Tibial Slope on Quadriceps Force and Joint Contact Forces in Posterior-Stabilized Total Knee Arthroplasty

    Directory of Open Access Journals (Sweden)

    Kyoung-Tak Kang

    2017-01-01

    Full Text Available This study aimed to determine the biomechanical effect of the posterior condylar offset (PCO and posterior tibial slope (PTS in posterior-stabilized (PS fixed-bearing total knee arthroplasty (TKA. We developed ±1, ±2, and ±3 mm PCO models in the posterior direction and −3°, 0°, 3°, and 6° PTS models using a previously validated FE model. The influence of changes in the PCO and PTS on the biomechanical effects under deep-knee-bend loading was investigated. The contact stress on the PE insert increased by 14% and decreased by 7% on average as the PCO increased and decreased, respectively, compared to the neutral position. In addition, the contact stress on post in PE insert increased by 18% on average as PTS increased from −3° to 6°. However, the contact stress on the patellar button decreased by 11% on average as PTS increased from −3° to 6° in all different PCO cases. The quadriceps force decreased by 14% as PTS increased from −3° to 6° in all PCO models. The same trend was found in patellar tendon force. Changes in PCO had adverse biomechanical effects whereas PTS increase had positive biomechanical effects. However, excessive PTS should be avoided to prevent knee instability and subsequent failure.

  17. A Remedy to Crises: Danish Special Operations Forces in Whole-of-Government Stabilization Engagements

    Science.gov (United States)

    2016-06-01

    special operations forces, capacity building, state building 15. NUMBER OF PAGES 89 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT... psychology , beliefs (such as religion), and behaviors.”66 This knowledge is essential for decision makers who maneuver not only against adversaries, but...To further influence and inform target audiences, the military uses a variety of information-operation capabilities, including psychological

  18. Probabilistic assessment of power system transient stability incorporating SMES

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Jiakun, E-mail: Jiakun.Fang@gmail.com [State Key Lab of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, No. 1037, Luoyu Road, Wuhan 430074 (China); Yao, Wei [State Key Lab of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, No. 1037, Luoyu Road, Wuhan 430074 (China); Wen, Jinyu, E-mail: jinyu.wen@hust.edu.cn [State Key Lab of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, No. 1037, Luoyu Road, Wuhan 430074 (China); Cheng, Shijie; Tang, Yuejin; Cheng, Zhuo [State Key Lab of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, No. 1037, Luoyu Road, Wuhan 430074 (China)

    2013-01-15

    Highlights: ► Probabilistic study of power system with wind farm and SMES is proposed. ► Quantitative relationship between system stability and SMES capacity is given. ► System stability increases with the capacity of the SMES. ► System stability decreases with the penetration of wind power. ► Together with the cost function, the coil size is optimized. -- Abstract: This paper presents a stochastic-based approach to evaluate the probabilistic transient stability index of the power system incorporating the wind farm and the SMES. Uncertain factors include both sequence of disturbance in power grid and stochastic generation of the wind farm. The spectrums of disturbance in the grid as the fault type, the fault location, the fault clearing time and the automatic reclosing process with their probabilities of occurrence are used to calculate the probability indices, while the wind speed statistics and parameters of the wind generator are used in a Monte Carlo simulation to generate samples for the studies. With the proposed method, system stability is ”measured”. Quantitative relationship of penetration level, SMES coil size and system stability is established. Considering the stability versus coil size to be the production curve, together with the cost function, the coil size is optimized economically.

  19. Probabilistic assessment of power system transient stability incorporating SMES

    International Nuclear Information System (INIS)

    Fang, Jiakun; Yao, Wei; Wen, Jinyu; Cheng, Shijie; Tang, Yuejin; Cheng, Zhuo

    2013-01-01

    Highlights: ► Probabilistic study of power system with wind farm and SMES is proposed. ► Quantitative relationship between system stability and SMES capacity is given. ► System stability increases with the capacity of the SMES. ► System stability decreases with the penetration of wind power. ► Together with the cost function, the coil size is optimized. -- Abstract: This paper presents a stochastic-based approach to evaluate the probabilistic transient stability index of the power system incorporating the wind farm and the SMES. Uncertain factors include both sequence of disturbance in power grid and stochastic generation of the wind farm. The spectrums of disturbance in the grid as the fault type, the fault location, the fault clearing time and the automatic reclosing process with their probabilities of occurrence are used to calculate the probability indices, while the wind speed statistics and parameters of the wind generator are used in a Monte Carlo simulation to generate samples for the studies. With the proposed method, system stability is ”measured”. Quantitative relationship of penetration level, SMES coil size and system stability is established. Considering the stability versus coil size to be the production curve, together with the cost function, the coil size is optimized economically

  20. New possibilities for slope stability assessment of spoil banks

    Energy Technology Data Exchange (ETDEWEB)

    Radl, A [Palivovy Kombinat, Vresova (Czechoslovakia)

    1991-03-01

    Discusses problems associated with slope stability of spoil banks consisting of sedimentary rocks from brown coal surface mining. Effects of rock physical properties on slope stability are analyzed: grain size distribution, compression strength, moisture content, angle of internal friction, etc. Mechanism of plastic slope deformation which occurs during a landslide is evaluated. Formulae for calculating slope stability considering stress distribution in a spoil bank (including all the main factors that influence stresses) are derived. Practical use of the gamma-gamma logging and logging schemes used in geodetic surveys of unstable spoil banks in Czechoslovakia (the Vintirov spoil bank in the Sokolov brown coal district) are discussed. 5 refs.

  1. Evaluation of the influence of fluoroquinolone chemical structure on stability: forced degradation and in silico studies

    Directory of Open Access Journals (Sweden)

    André Valle de Bairros

    2018-05-01

    Full Text Available ABSTRACT Fluoroquinolones are a known antibacterial class commonly used around the world. These compounds present relative stability and they may show some adverse effects according their distinct chemical structures. The chemical hydrolysis of five fluoroquinolones was studied using alkaline and photolytic degradation aiming to observe the differences in molecular reactivity. DFT/B3LYP-6.31G* was used to assist with understanding the chemical structure degradation. Gemifloxacin underwent degradation in alkaline medium. Gemifloxacin and danofloxacin showed more degradation perceptual indices in comparison with ciprofloxacin, enrofloxacin and norfloxacin in photolytic conditions. Some structural features were observed which may influence degradation, such as the presence of five member rings attached to the quinolone ring and the electrostatic positive charges, showed in maps of potential electrostatic charges. These measurements may be used in the design of effective and more stable fluoroquinolones as well as the investigation of degradation products from stress stability assays.

  2. [Stability of orthodontic correction: preconditions of relapses caused by occlusal forces].

    Science.gov (United States)

    Shishkin, K M; Arsenina, O I; Shishkin, M K; Popova, N V

    The aim of the study was to determine the prognostic criteria of orthodontic treatment success in a group of patients with crowded teeth position and a neutral occlusion. The study included 150 patients (123 female and 27 male) with the average follow-up of 10.02±2.88 years and average retention phase of 6.15±2.98 years. Teeth positions, dental arches form, occlusal contacts and periodontal status were studied. Dentition changes after orthodontic correction should be considered as a result of adaptive compensatory balance. The resultant force acting on teeth and the direction of it determine displacement of teeth. The leading relapse precontidion induced by the occlusal forces was the interference of the canines, mandible deviation and asymmetry, muscle tone disorders.

  3. Periodic Forcing of Inhibition-Stabilized Networks: Nonlinear Resonances and Phase-Amplitude Coupling

    OpenAIRE

    Veltz, Romain; Sejnowski, Terrence J.

    2015-01-01

    International audience; Inhibition stabilized networks (ISNs) are neural architectures with strong positive feedback among pyramidal neurons balanced by strong negative feedback from in-hibitory interneurons, a circuit element found in the hippocampus and the primary vi-sual cortex. In their working regime, ISNs produce damped oscillations in the γ-range in response to inputs to the inhibitory population. In order to understand the proper-ties of interconnected ISNs, we investigated periodic ...

  4. Stability and Support Operations, Intervening Armed Forces and the Population They Serve: Defining a Doctrine

    Science.gov (United States)

    2002-05-24

    Chauvancy, Le moral du soldat occidental dans les nouveaux contextes d’intervention » (The Western Soldier Moral In The New Intervention Environment). MARS...Lawrence A. “Military Stability and Support Operations: Analogies, Patterns And Recurring Themes”. Military Review 4 (July-august 1997): 51. WEB SITES...And General Staff College, Fort Leavenworth, Kansas, 1967. BOOKS IN FRENCH Corvisier, André. Histoire militaire de la France, 4. de 1940 à nos jours

  5. Qualitative stability assessment of cut slopes along the National ...

    Indian Academy of Sciences (India)

    Jagadish Kundu

    2017-11-23

    Nov 23, 2017 ... Landslide is the most common hazard in the state. Every year ... table 2. 3. Stability evaluation (qualitative) ..... the slopes using quantified method (Sonmez and ..... Research to Engineering, Proceedings of the 2nd Interna-.

  6. Leveraging Naval Riverine Forces to Achieve Information Superiority in Stability Operations

    Science.gov (United States)

    2010-12-01

    Commanding Officer, USS TORTUGA (LSD-46) surveys the extent of flooding in the 9th Ward, New Orleans, LA, after Hurricane Katrina (From Watkins...13). Even though forces had been on site for many days prior to the author’s arrival on USS TORTUGA eight days after the storm, on the first day...Commanding Officer, USS TORTUGA (LSD-46) surveys the extent of flooding in the 9th Ward, New Orleans, LA, after Hurricane Katrina (From Watkins, 2005

  7. Forelimb and hindlimb ground reaction forces of walking cats: assessment and comparison with walking dogs.

    Science.gov (United States)

    Corbee, R J; Maas, H; Doornenbal, A; Hazewinkel, H A W

    2014-10-01

    The primary aim of this study was to assess the potential of force plate analysis for describing the stride cycle of the cat. The secondary aim was to define differences in feline and canine locomotion based on force plate characteristics. Ground reaction forces of 24 healthy cats were measured and compared with ground reaction forces of 24 healthy dogs. Force-time waveforms in cats generated by force plate analysis were consistent, as reflected by intra-class correlation coefficients for peak vertical force, peak propulsive force and peak braking force (0.94-0.95, 0.85-0.89 and 0.89-0.90, respectively). Compared with dogs, cats had a higher peak vertical force during the propulsion phase (cat, 3.89 ± 0.19 N/kg; dog, 3.03 ± 0.16 N/kg), and a higher hindlimb propulsive force (cat, -1.08 ± 0.13 N/kg; dog, (-0.87 ± 0.13 N/kg) and hindlimb impulse (cat, -0.18 ± 0.03 N/kg; dog, -0.14 ± 0.02 N/kg). Force plate analysis is a valuable tool for the assessment of locomotion in cats, because it can be applied in the clinical setting and provides a non-invasive and objective measurement of locomotion characteristics with high repeatability in cats, as well as information about kinetic characteristics. Differences in force-time waveforms between cats and dogs can be explained by the more crouched position of cats during stance and their more compliant gait compared with dogs. Feline waveforms of the medio-lateral ground reaction forces also differ between cats and dogs and this can be explained by differences in paw supination-pronation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Environmental assessment of different strategies for production of stabilized yeast

    OpenAIRE

    Monclus, Vincent; Pénicaud, Caroline; Perret, Bruno; Fonseca, Fernanda

    2016-01-01

    Yeast are widely used for producing fermented (bread, beer...) and health benefit (probiotics) products. The production of stable and active yeast involves fermentation, concentration, protection, drying (stabilization) and storage. During the stabilization and storage steps, the cells face numerous stress which may deteriorate functional properties and cause cell death. Different strategies can be used to preserve cell survival, such as changing growth medium for fermentation or adapting pro...

  9. Implications of Representative Concentration Pathway 4.5 Methane Emissions to Stabilize Radiative Forcing

    Energy Technology Data Exchange (ETDEWEB)

    Emanuel, William R.; Janetos, Anthony C.

    2013-02-01

    Increases in the abundance of methane (CH4) in the Earth’s atmosphere are responsible for significant radiative forcing of climate change (Forster et al., 2007; Wuebbles and Hayhoe, 2002). Since 1750, a 2.5 fold increase in atmospheric CH4 contributed 0.5 W/m2 to direct radiative forcing and an additional 0.2 W/m2 indirectly through changes in atmospheric chemistry. Next to water and carbon dioxide (CO2), methane is the most abundant greenhouse gas in the troposphere. Additionally, CH4 is significantly more effective as a greenhouse gas on a per molecule basis than is CO2, and increasing atmospheric CH4 has been second only to CO2 in radiative forcing (Forster et al., 2007). The chemical reactivity of CH4 is important to both tropospheric and stratospheric chemistry. Along with carbon monoxide, methane helps control the amount of the hydroxyl radical (OH) in the troposphere where oxidation of CH4 by OH leads to the formation of formaldehyde, carbon monoxide, and ozone.

  10. Assessment and mapping of slope stability based on slope units: A ...

    Indian Academy of Sciences (India)

    Shallow landslide; infinite slope stability equation; return period precipitation; assessment; slope unit. ... 2010), logistic regression ... model to assess the hazard of shallow landslides ..... grating a fuzzy k-means classification and a Bayesian.

  11. NUMBER OF SUCCESSIVE CYCLES NECESSARY TO ACHIEVE STABILITY OF SELECTED GROUND REACTION FORCE VARIABLES DURING CONTINUOUS JUMPING

    Directory of Open Access Journals (Sweden)

    Jasmes M.W. Brownjohn

    2009-12-01

    Full Text Available Because of inherent variability in all human cyclical movements, such as walking, running and jumping, data collected across a single cycle might be atypical and potentially unable to represent an individual's generalized performance. The study described here was designed to determine the number of successive cycles due to continuous, repetitive countermovement jumping which a test subject should perform in a single experimental session to achieve stability of the mean of the corresponding continuously measured ground reaction force (GRF variables. Seven vertical GRF variables (period of jumping cycle, duration of contact phase, peak force amplitude and its timing, average rate of force development, average rate of force relaxation and impulse were extracted on the cycle-by-cycle basis from vertical jumping force time histories generated by twelve participants who were jumping in response to regular electronic metronome beats in the range 2-2.8 Hz. Stability of the selected GRF variables across successive jumping cycles was examined for three jumping rates (2, 2.4 and 2.8 Hz using two statistical methods: intra-class correlation (ICC analysis and segmental averaging technique (SAT. Results of the ICC analysis indicated that an average of four successive cycles (mean 4.5 ± 2.7 for 2 Hz; 3.9 ± 2.6 for 2.4 Hz; 3.3 ± 2.7 for 2.8 Hz were necessary to achieve maximum ICC values. Except for jumping period, maximum ICC values took values from 0.592 to 0.991 and all were significantly (p < 0.05 different from zero. Results of the SAT revealed that an average of ten successive cycles (mean 10.5 ± 3.5 for 2 Hz; 9.2 ± 3.8 for 2.4 Hz; 9.0 ± 3.9 for 2.8 Hz were necessary to achieve stability of the selected parameters using criteria previously reported in the literature. Using 10 reference trials, the SAT required standard deviation criterion values of 0.49, 0.41 and 0.55 for 2 Hz, 2.4 Hz and 2.8 Hz jumping rates, respectively, in order to approximate

  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. 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.

  14. The application of the Accelerated Stability Assessment Program (ASAP) to quality by design (QbD) for drug product stability.

    Science.gov (United States)

    Waterman, Kenneth Craig

    2011-09-01

    An isoconversion paradigm, where times in different temperature and humidity-controlled stability chambers are set to provide a fixed degradant level, is shown to compensate for the complex, non-single order kinetics of solid drug products. A humidity-corrected Arrhenius equation provides reliable estimates for temperature and relative humidity effects on degradation rates. A statistical protocol is employed to determine best fits for chemical stability data, which in turn allows for accurate estimations of shelf life (with appropriate confidence intervals) at any storage condition including inside packaging (based on the moisture vapor transmission rate of the packaging and moisture sorption isotherms of the internal components). These methodologies provide both faster results and far better predictions of chemical stability limited shelf life (expiry) than previously possible. Precise shelf-life estimations are generally determined using a 2-week, product-specific protocol. Once the model for a product is developed, it can play a critical role in providing the product understanding necessary for a quality by design (QbD) filing for product approval and enable rational control strategies to assure product stability. Moreover, this Accelerated Stability Assessment Program (ASAP) enables the coupling of product attributes (e.g., moisture content, packaging options) to allow for flexibility in how control strategies are implemented to provide a balance of cost, speed, and other factors while maintaining adequate stability.

  15. Bifurcation and stability of forced convection in tightly coiled ducts: multiplicity

    International Nuclear Information System (INIS)

    Wang Liqiu; Pang, Ophelia; Cheng Lin

    2005-01-01

    A numerical study is made on the fully developed bifurcation structure of the forced convection in tightly coiled ducts of square cross-section. In addition to the examination of structural changes of three known solution branches found in loosely coiled ducts, three new solution branches are found. These new branches are isolated from the three known branches. The flows on these new branches are in a symmetric 4-cell state, a symmetric 8-cell state, an asymmetric 2-cell state, an asymmetric 5-cell state, an asymmetric 7-cell state, or an asymmetric 8-cell structure

  16. Assessment of Effective Prestressed Force of Nuclear Containment Building using SI Technique

    Energy Technology Data Exchange (ETDEWEB)

    Lee, H. P.; Jang, J. B.; Hwang, K. M.; Song, Y. C. [Korea Electric Power Research Institute, Daejeon (Korea, Republic of)

    2010-10-15

    Bonded tendons have been used in reactor buildings of heavy water reactors and the light water reactors of some nuclear power plants operating in Korea. The assessment of prestressed forces on those bonded tendons is becoming an important issue in assuring their continuous operation beyond their design life. In order to assess the effective prestressed force on the bonded tendon, indirect assessment techniques have been applying to the test beams which were manufactured on construction time. Therefore, this research mainly forced to establish the assessment methodology to measure directly the effective prestressed force on the bonded tendon of containment buildings using System Identification (SI) technique. To accomplish this purpose, simple SI method was proposed and adapted three dimensional finite element analysis of the 1:4 scale prestressed concrete containment vessel (PCCV) tested by Sandia National Laboratory in 2000

  17. Assessment of Structural Resistance of building 4862 to Earthquake and Tornado Forces [SEC 1 and 2

    International Nuclear Information System (INIS)

    METCALF, I.L.

    1999-01-01

    This report presents the results of work done for Hanford Engineering Laboratory under contract Y213-544-12662. LATA performed an assessment of building 4862 resistance to earthquake and tornado forces

  18. Assessment of Structural Resistance of building 4862 to Earthquake and Tornado Forces [SEC 1 and 2

    Energy Technology Data Exchange (ETDEWEB)

    METCALF, I.L.

    1999-12-06

    This report presents the results of work done for Hanford Engineering Laboratory under contract Y213-544-12662. LATA performed an assessment of building 4862 resistance to earthquake and tornado forces.

  19. Damage Stability Assessment of an HSC after Grounding

    DEFF Research Database (Denmark)

    Ravn, Erik Sonne; Simonsen, Bo Cerup; Baatrup, Jan

    2000-01-01

    Currently a substantial effort is done within the International Maritime Organisation (IMO) on revision of the High Speed Craft (HSC) Code. A main issue is the extent of bottom damage and raking damage due to grounding on hard rocks and the corresponding requirements to the damage stability...... of the vessel. It has been found that high-speed craft can experience a damage length up to 100% of the ship length. It has, however, also been argued that the damage stability requirements should reflect the size and probability of the damage with a reduction of the demand for the largest damages.......In the present paper a detailed grounding and damage stability analysis is carried out for two specific HSC, a mono-hull (86 m) and a catamaran (69 m). First various grounding scenarios are considered with different values of the forward speed and ground geometry. The results indicate that 100% bottom damage...

  20. Assessment on the mechanical stability of underground excavations

    International Nuclear Information System (INIS)

    Kuroki, Shigemori; Taniguchi, Wataru; Sugino, Hiroyuki; Koo, Shigeru; Hasegawa, Hiroshi; Kubota, Shigeru; Dewa, Katsuyuki

    1999-11-01

    It is planned to construct the tunnels and emplace waste packages at several hundred meters to 1,000 meters under the ground for the repository of high-level radioactive waste based on a policy to assure the safe life environment. It is required to be mechanically stable for the tunnels to assure the work safety throughout the construction, operation and closure phase. In this report, the mechanical stability of tunnels, that is a factor of design requisites, was evaluated by the analyses to present an outline of the technical reliability of geological disposal. To put it concretely, the tunnel sections were determined to have the required areas and shapes, and the analyses on the mechanical stability at tunnel excavations and earthquake, at tunnel intersections were conducted by the theoretical analysis and finite element method. The results obtained by these investigations are shown below: It will be able to construct the tunnels with present techniques. The mechanical stability of tunnels will be assured if proper supports are given, and adequate tunnel spacing and disposal-pit pitches are set. The mechanical stability will be assured at the tunnel intersections if proper reinforcement measures are taken. The reinforcement will be required for the intersection areas over the distance of 1D (D: diameter of tunnels) on the obtuse angle side, and 4D on the acute angle side, when intersection angle is set at 30 degrees. The investigations were conducted on the assumption that the experienced big earthquake occurred. The results show that the effect of earthquake on the mechanical stability of tunnels is small, and tunnels are stable at the earthquake when the mechanical stability at tunnel excavations is assured. (author)

  1. Assessment of the Prony's method for BWR stability analysis

    International Nuclear Information System (INIS)

    Ortiz-Villafuerte, Javier; Castillo-Duran, Rogelio; Palacios-Hernandez, Javier C.

    2011-01-01

    Highlights: → This paper describes a method to determine the degree of stability of a BWR. → Performance comparison between Prony's and common AR techniques is presented. → Benchmark data and actual BWR transient data are used for comparison. → DR and f results are presented and discussed. → The Prony's method is shown to be a robust technique for BWR stability. - Abstract: It is known that Boiling Water Reactors are susceptible to present power oscillations in regions of high power and low coolant flow, in the power-flow operational map. It is possible to fall in one of such instability regions during reactor startup, since both power and coolant flow are being increased but not proportionally. One other possibility for falling into those areas is the occurrence of a trip of recirculation pumps. Stability monitoring in such cases can be difficult, because the amount or quality of power signal data required for calculation of the stability key parameters may not be enough to provide reliable results in an adequate time range. In this work, the Prony's Method is presented as one complementary alternative to determine the degree of stability of a BWR, through time series data. This analysis method can provide information about decay ratio and oscillation frequency from power signals obtained during transient events. However, so far not many applications in Boiling Water Reactors operation have been reported and supported to establish the scope of using such analysis for actual transient events. This work presents first a comparison of decay ratio and frequency oscillation results obtained by Prony's method and those results obtained by the participants of the Forsmark 1 and 2 Boiling Water Reactor Stability Benchmark using diverse techniques. Then, a comparison of decay ratio and frequency oscillation results is performed for four real BWR transient event data, using Prony's method and two other techniques based on an autoregressive modeling. The four

  2. Self-Described Differences Between Legs in Ballet Dancers: Do They Relate to Postural Stability and Ground Reaction Force Measures?

    Science.gov (United States)

    Mertz, Laura; Docherty, Carrie

    2012-12-01

    Ballet technique classes are designed to train dancers symmetrically, but they may actually create a lateral bias. It is unknown whether dancers in general are functionally asymmetrical, or how an individual dancer's perceived imbalance between legs might manifest itself. The purpose of this study was to examine ballet dancers' lateral preference by analyzing their postural stability and ground reaction forces in fifth position when landing from dance-specific jumps. Thirty university ballet majors volunteered to participate in this study. The subjects wore their own ballet technique shoes and performed fundamental ballet jumps out of fifth position on a force plate. The force plate recorded center of pressure (COP) and ground reaction force (GRF) data. Each subject completed a laterality questionnaire that determined his or her preferred landing leg for ballet jumps, self-identified stronger leg, and self-identified leg with better balance. All statistical comparisons were made between the leg indicated on the laterality questionnaire and the other leg (i.e., if the dancer's response to a question was "left," the comparison was made with the left leg as the "preferred" leg and the right leg as the "non-preferred leg"). No significant differences were identified between the limbs in any of the analyses conducted (all statistical comparisons produced p values > 0.05). The results of this study indicate that a dancer's preferential use of one limb over the other has no bearing on GRFs or balance ability after landing jumps in ballet. Similarly, dancers' opinions of their leg characteristics (such as one leg being stronger than the other) seem not to correlate with the dancers' actual ability to absorb GRFs or to balance when landing from ballet jumps.

  3. Techniques for Liquid Rocket Combustion Spontaneous Stability and Rough Combustion Assessments

    Science.gov (United States)

    Kenny, R. J.; Giacomoni, C.; Casiano, M. J.; Fischbach, S. R.

    2016-01-01

    This work presents techniques for liquid rocket engine combustion stability assessments with respect to spontaneous stability and rough combustion. Techniques covering empirical parameter extraction, which were established in prior works, are applied for three additional programs: the F-1 Gas Generator (F1GG) component test program, the RS-84 preburner component test program, and the Marshall Integrated Test Rig (MITR) program. Stability assessment parameters from these programs are compared against prior established spontaneous stability metrics and updates are identified. Also, a procedure for comparing measured with predicted mode shapes is presented, based on an extension of the Modal Assurance Criterion (MAC).

  4. Middle Classes in China: Force for Political Change or Guarantee of Stability?

    Directory of Open Access Journals (Sweden)

    Luigi Tomba

    2009-12-01

    Full Text Available This article looks at the factors that contributed to the production of a Chinese middle class during the reform period and to the role that a growing group of big spenders and consumers play for China’s economic growth and political stability. It argues that a dramatic status enhancement for wage-earning Chinese professionals was among the major determinants of social change in the late 1990s and that this process happened despite the market more than because of it. The ongoing development of a high-consuming urban society in China has been as much the outcome of the social engineering project of the contemporary reformist state and its agencies as it has been a consequence of the opening up of the economy and society.

  5. Retrofitting Forced Air Combi Systems: A Cold Climate Field Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, Ben [NorthernSTAR, St. Paul, MN (United States); Bohac, Dave [NorthernSTAR, St. Paul, MN (United States); McAlpine, Jack [NorthernSTAR, St. Paul, MN (United States); Hewett, Martha [NorthernSTAR, St. Paul, MN (United States)

    2017-06-01

    This project analyzed combined condensing water heaters or boilers and hydronic air coils to provide high efficiency domestic hot water (DHW) and forced air space heating. Called "combi" systems, they provided similar space and water heating performance less expensively than installing two condensing appliances. The system's installed costs were cheaper than installing a condensing furnace and either a condensing tankless or condensing storage water heater. However, combi costs must mature and be reduced before they are competitive with a condensing furnace and power vented water heater (energy factor of 0.60). Better insulation and tighter envelopes are reducing space heating loads for new and existing homes. For many homes, decreased space heating loads make it possible for both space and domestic water heating loads to be provided with a single heating plant. These systems can also eliminate safety issues associated with natural draft appliances through the use of one common sealed combustion vent. The combined space and water heating approach was not a new idea. Past systems have used non-condensing heating plants, which limited their usefulness in climates with high heating loads. Previous laboratory work (Schoenbauer et al. 2012a) showed that proper installation was necessary to achieve condensing with high efficiency appliances. Careful consideration was paid to proper system sizing and minimizing the water temperature returning from the air handling unit to facilitate condensing operation.

  6. Retrofitting Forced Air Combi Systems: A Cold Climate Field Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, Ben [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR Building America Partnership; Bohac, Dave [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR Building America Partnership; McAlpine, Jake [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR Building America Partnership; Hewett, Martha [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR Building America Partnership

    2017-06-23

    This project analyzed combined condensing water heaters or boilers and hydronic air coils to provide high efficiency domestic hot water (DHW) and forced air space heating. Called 'combi' systems, they provided similar space and water heating performance less expensively than installing two condensing appliances. The system's installed costs were cheaper than installing a condensing furnace and either a condensing tankless or condensing storage water heater. However, combi costs must mature and be reduced before they are competitive with a condensing furnace and power vented water heater (energy factor of 0.60). Better insulation and tighter envelopes are reducing space heating loads for new and existing homes. For many homes, decreased space heating loads make it possible for both space and domestic water heating loads to be provided with a single heating plant. These systems can also eliminate safety issues associated with natural draft appliances through the use of one common sealed combustion vent. The combined space and water heating approach was not a new idea. Past systems have used non-condensing heating plants, which limited their usefulness in climates with high heating loads. Previous laboratory work (Schoenbauer et al. 2012a) showed that proper installation was necessary to achieve condensing with high efficiency appliances. Careful consideration was paid to proper system sizing and minimizing the water temperature returning from the air handling unit to facilitate condensing operation.

  7. Quantitative Assessment of Interutterance Stability: Application to Dysarthria

    Science.gov (United States)

    Cummins, Fred; Lowit, Anja; van Brenk, Frits

    2014-01-01

    Purpose: Following recent attempts to quantify articulatory impairment in speech, the present study evaluates the usefulness of a novel measure of motor stability to characterize dysarthria. Method: The study included 8 speakers with ataxic dysarthria (AD), 16 speakers with hypokinetic dysarthria (HD) as a result of Parkinson's disease, and…

  8. THE USE OF GEOMORPHOLOGY IN THE ASSESSMENT OF STREAM STABILITY

    Science.gov (United States)

    Various applications of geomorphic data and stream stability rating systems are being considered in order to establish tools for the development of TMDLs for clean sediment in streams. The transport of "clean" sediment, as opposed to contaminated sediment, is of concern to the en...

  9. Assessing the roll stability of heavy vehicles in South Africa

    CSIR Research Space (South Africa)

    Benade, R

    2016-07-01

    Full Text Available of these crashes involve heavy vehicle rollover. The regulations in the National Road Traffic Act of South Africa that govern heavy vehicle design do not directly address the roll stability of heavy vehicles. The internationally accepted method of regulating roll...

  10. Hollow Force, Hollow Metaphor: Assessing The Current Defense Drawdown

    Science.gov (United States)

    2016-04-04

    better prioritized. Army Readiness Secretary of the Army John McHugh and Chief of Staff of the Army (CSA), General Raymond Odierno, assessed in...forming the Army’s readiness narrative— Army leaders see the cuts as inconsistent with an uncertain and volatile strategic environment. McHugh and...John M. McHugh and Raymond T. Odierno, statement made on the Posture of the United States Army, on March 18, 2015, to the Senate Armed Services

  11. Cape Canaveral Air Force Station integrated resource assessment. Volume 3, Resource assessment

    Energy Technology Data Exchange (ETDEWEB)

    Sandusky, W.F.; Eichman, C.J.; King, D.A.; McMordie, K.L.; Parker, S.A.; Shankle, S.A.; Wahlstrom, R.R.

    1994-03-01

    The U.S. Air Force (USAF) has tasked the Pacific Northwest Laboratory (PNL) in support of the U.S. Department of Energy (DOE) Federal Energy Management Program (FEMP), to identify, evaluate, and assist in acquiring all cost-effective energy projects at Cape Canaveral Air Force Station (AFS). Projects considered can be either in the form of energy management or energy conservation. The overall efforts of this task are based on a model program 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 Cape Canaveral AFS, which is located approximately 10 miles north 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 (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 operations and maintenance (O&M), and, when applicable, a discussion of energy supply and demand, energy security, and environmental issues. Descriptions of the evaluation methodologies and technical and cost assumptions are 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.

  12. Griffiss Air Force Base integrated resource assessment. Volume 3, Electric resource assessment

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, P.R.; Shankle, S.A.; Elliott, D.B.; Stucky, D.J.; Keller, J.M.; Wahlstrom, R.R.; Dagle, J.E.; Gu, A.Y.

    1993-09-01

    The US Air Force Air Combat Command (ACC) has tasked the US Department of Energy (DOE) Federal Energy Management Program (FEMP) to identify, evaluate, and assist in acquiring all cost-effective energy projects at Griffiss Air Force Base (AFB). FEMP, with support from the Pacific Northwest Laboratory (PNL), is designing this model program for federal customers served by the Niagara Mohawk Power Company. The program with Griffiss AFB will (1) identify and evaluate all cost-effective electric energy projects; (2) develop a schedule for project acquisition considering project type, size, timing, capital requirements, as well as energy and dollar savings; and (3) secure 100% of the financing required to implement electric energy efficiency projects from Niagara Mohawk and have them procure the necessary contractors to perform detailed audits and install the technologies. This report provides the results of the electric energy resource opportunity (ERO) assessments performed by PNL at one of Niagara Mohawk`s primary federal facilities, the ACC Griffiss AFB facility located near Rome, New York. The results of the analyses of EROs are presented in seven common energy end-use categories. A narrative description of each ERO provides information on the initial cost, energy and dollar savings; impacts on operations and maintenance (O&M); and, when applicable, a discussion of energy supply and demand, energy security, and environmental issues. The evaluation methodology and technical and cost assumptions are also described for each ERO. Summary tables present the operational performance of energy end-use equipment before and after the implementation of each ERO and the results of the life-cycle cost analysis indicating the net present value (NPV) and savings-to-investment ratio (SIR) of each ERO.

  13. 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.

  14. Assessment of stability during gait in patients with spinal deformity-A preliminary analysis using the dynamic stability margin.

    Science.gov (United States)

    Simon, Anne-Laure; Lugade, Vipul; Bernhardt, Kathie; Larson, A Noelle; Kaufman, Kenton

    2017-06-01

    Daily living activities are dynamic, requiring spinal motion through space. Current assessment of spinal deformities is based on static measurements from full-spine standing radiographs. Tools to assess dynamic stability during gait might be useful to enhance the standard evaluation. The aim of this study was to evaluate gait dynamic imbalance in patients with spinal deformity using the dynamic stability margin (DSM). Twelve normal subjects and 17 patients with spinal deformity were prospectively recruited. A kinematic 3D gait analysis was performed for the control group (CG) and the spinal deformity group (SDG). The DSM (distance between the extrapolated center of mass and the base of support) and time-distance parameters were calculated for the right and left side during gait. The relationship between DSM and step length was assessed using three variables: gait stability, symmetry, and consistency. Variables' accuracy was validated by a discriminant analysis. Patients with spinal deformity exhibited gait instability according to the DSM (0.25m versus 0.31m) with decreased velocity (1.1ms -1 versus 1.3ms -1 ) and decreased step length (0.32m versus 0.38m). According to the discriminant analysis, gait stability was the more accurate variable (area under the curve AUC=0.98) followed by gait symmetry and consistency. However, gait consistency showed 100% of specificity, sensitivity, and accuracy of precision. The DSM showed that patients with spinal malalignment exhibit decreased gait stability, symmetry, and consistency besides gait time-distance parameter changes. Additional work is required to determine how to apply the DSM for preoperative and postoperative spinal deformity management. Copyright © 2017. Published by Elsevier B.V.

  15. Assessment of oscillatory stability constrained available transfer capability

    International Nuclear Information System (INIS)

    Jain, T.; Singh, S.N.; Srivastava, S.C.

    2009-01-01

    This paper utilizes a bifurcation approach to compute oscillatory stability constrained available transfer capability (ATC) in an electricity market having bilateral as well as multilateral transactions. Oscillatory instability in non-linear systems can be related to Hopf bifurcation. At the Hopf bifurcation, one pair of the critical eigenvalues of the system Jacobian reaches imaginary axis. A new optimization formulation, including Hopf bifurcation conditions, has been developed in this paper to obtain the dynamic ATC. An oscillatory stability based contingency screening index, which takes into account the impact of transactions on severity of contingency, has been utilized to identify critical contingencies to be considered in determining ATC. The proposed method has been applied for dynamic ATC determination on a 39-bus New England system and a practical 75-bus Indian system considering composite static load as well as dynamic load models. (author)

  16. Task Force on Workplace Violence: Part I. The assessment.

    Science.gov (United States)

    Carroll, V

    1997-06-01

    Prevention is key in dealing with workplace violence. Assessment, open communication within the workplace, well-designed policies, and adequate staff training form the framework for an effective violence reduction plan. Nurses offer invaluable resources to each other, their patients. and their workplace. Through effective planning and problem-solving, we can collaborate with other disciplines to enhance the future of health care and provide for a safer workplace. Just as we are advocates for safe and quality health care for our patients, we must also be champions for creating a safe work environment for ourselves.

  17. Combustion Stability Assessments of the Black Brant Solid Rocket Motor

    Science.gov (United States)

    Fischbach, Sean

    2014-01-01

    The Black Brant variation of the Standard Brant developed in the 1960's has been a workhorse motor of the NASA Sounding Rocket Project Office (SRPO) since the 1970's. In March 2012, the Black Brant Mk1 used on mission 36.277 experienced combustion instability during a flight at White Sands Missile Range, the third event in the last four years, the first occurring in November, 2009, the second in April 2010. After the 2010 event the program has been increasing the motor's throat diameter post-delivery with the goal of lowering the chamber pressure and increasing the margin against combustion instability. During the most recent combustion instability event, the vibrations exceeded the qualification levels for the Flight Termination System. The present study utilizes data generated from T-burner testing of multiple Black Brant propellants at the Naval Air Warfare Center at China Lake, to improve the combustion stability predictions for the Black Brant Mk1 and to generate new predictions for the Mk2. Three unique one dimensional (1-D) stability models were generated, representing distinct Black Brant flights, two of which experienced instabilities. The individual models allowed for comparison of stability characteristics between various nozzle configurations. A long standing "rule of thumb" states that increased stability margin is gained by increasing the throat diameter. In contradiction to this experience based rule, the analysis shows that little or no margin is gained from a larger throat diameter. The present analysis demonstrates competing effects resulting from an increased throat diameter accompanying a large response function. As is expected, more acoustic energy was expelled through the nozzle, but conversely more acoustic energy was generated due to larger gas velocities near the propellant surfaces.

  18. Assessing Romanian financial sector stability: the importance of the international economic climate

    OpenAIRE

    Albulescu, Claudiu Tiberiu

    2008-01-01

    The aim of this paper is to develop an aggregate stability index for the Romanian financial system. The index which is meant to enhance the set of analysis used by the central bank to assess the financial stability accurately reflects the financial stability dynamics and the periods with financial turbulences during 1997-2007 in Romania. By the application of a technique which enables the measurement of the components’ contribution to the aggregate index volatility, we show that some individu...

  19. The response of a harmonically forced premixed flame stabilized on a heat-conducting bluff-body

    KAUST Repository

    Kedia, Kushal S.

    2015-01-01

    © 2014 The Combustion Institute. The objective of this work is to investigate the unsteady response of a bluff-body stabilized laminar premixed flame to harmonic inlet velocity excitation. A time series analysis was performed to analyze the physical sequence of events at a fixed longitudinal forcing frequency of 100 Hz for cases with (1) two different equivalence ratios and (2) two different thermal properties of the stabilizing bluff-body. It was observed that conjugate heat exchange between the heat conducting bluff-body and the surrounding reacting flow has a crucial impact on the dynamic response. The flame area and anchoring location, the net conjugate heat transfer and the total heat release underwent significant oscillations. The latter was mean shifted and had multiple frequencies. The burning velocity varied significantly along the flame length and the recirculation zone underwent complex changes in its shape and size during an unsteady cycle. The lower equivalence ratio case exhibited vortex shedding after an initial symmetric response with periodic flame extinction and re-ignition along its surface, unlike the higher equivalence ratio case. The metal/ceramic bluff-body showed a net heat transfer directed from/to the bluff-body, to/from the reacting flow during an unsteady cycle, resulting in a significantly different flame response for the two otherwise equivalent cases.

  20. Stabilization

    Directory of Open Access Journals (Sweden)

    Muhammad H. Al-Malack

    2016-07-01

    Full Text Available Fuel oil flyash (FFA produced in power and water desalination plants firing crude oils in the Kingdom of Saudi Arabia is being disposed in landfills, which increases the burden on the environment, therefore, FFA utilization must be encouraged. In the current research, the effect of adding FFA on the engineering properties of two indigenous soils, namely sand and marl, was investigated. FFA was added at concentrations of 5%, 10% and 15% to both soils with and without the addition of Portland cement. Mixtures of the stabilized soils were thoroughly evaluated using compaction, California Bearing Ratio (CBR, unconfined compressive strength (USC and durability tests. Results of these tests indicated that stabilized sand mixtures could not attain the ACI strength requirements. However, marl was found to satisfy the ACI strength requirement when only 5% of FFA was added together with 5% of cement. When the FFA was increased to 10% and 15%, the mixture’s strength was found to decrease to values below the ACI requirements. Results of the Toxicity Characteristics Leaching Procedure (TCLP, which was performed on samples that passed the ACI requirements, indicated that FFA must be cautiously used in soil stabilization.

  1. Assessment of metabolic stability using the rainbow trout (Oncorhynchus mykiss) liver S9 fraction

    Science.gov (United States)

    Standard protocols are given for assessing metabolic stability in rainbow trout using the liver S9 fraction. These protocols describe the isolation of S9 fractions from trout livers, evaluation of metabolic stability using a substrate depletion approach, and expression of the res...

  2. Applying programmatic risk assessment to nuclear materials stabilization R and D planning

    International Nuclear Information System (INIS)

    Brown-Van Hoozer, S.A.; Kenley, C.R.

    1997-01-01

    A systems engineering approach to programmatic risk assessment, derived from the aerospace industry, was applied to various stabilization technologies to assess their relative maturity and availability for use in stabilizing nuclear materials. The assessment provided valuable information for trading off available technologies and identified the at-risk technologies that will require close tracking by the Department of Energy (DOE) to mitigate programmatic risks. This paper presents the programmatic risk assessment methodology developed for the 1995 R and D Plan and updated for the 1996 R and D Plan. Results of the 1996 assessment also are presented (DOE/ID-10561, 1996)

  3. Strategies for Voltage Control and Transient Stability Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hiskens, Ian A.

    2013-09-25

    As wind generation grows, its influence on power system performance will becoming increasingly noticeable. Wind generation di ffers from traditional forms of generation in numerous ways though, motivating the need to reconsider the usual approaches to power system assessment and performance enhancement. The project has investigated the impact of wind generation on transient stability and voltage control, identifying and addressing issues at three distinct levels of the power system: 1) at the device level, the physical characteristics of wind turbine generators (WTGs) are quite unlike those of synchronous machines, 2) at the wind-farm level, the provision of reactive support is achieved through coordination of numerous dissimilar devices, rather than straightforward generator control, and 3) from a systems perspective, the location of wind-farms on the sub-transmission network, coupled with the variability inherent in their power output, can cause complex voltage control issues. The project has sought to develop a thorough understanding of the dynamic behaviour of type-3 WTGs, and in particular the WECC generic model. The behaviour of such models is governed by interactions between the continuous dynamics of state variables and discrete events associated with limits. It was shown that these interactions can be quite complex, and may lead to switching deadlock that prevents continuation of the trajectory. Switching hysteresis was proposed for eliminating deadlock situations. Various type-3 WTG models include control blocks that duplicate integrators. It was shown that this leads to non-uniqueness in the conditions governing steady-state, and may result in pre- and post-disturbance equilibria not coinciding. It also gives rise to a zero eigenvalue in the linearized WTG model. In order to eliminate the anomalous behaviour revealed through this investigation, WECC has now released a new generic model for type-3 WTGs. Wind-farms typically incorporate a variety of

  4. A geometric criterion for the stability of forced oscillations in non-linear mechanics (1961); Un critere geometrique de stabilite des oscillations forcees en mecanique non lineaire (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Blaquiere, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1961-07-01

    The author completes the two-parameter diagram theory which he has previously explained, by giving a geometric criterion of stability for a non-linear system under forced conditions. After two simple geometric transformations of the diagram he obtains the separators which are the boundary conditions for the zones of stability. (author) [French] L'auteur complete la theorie du diagramme a deux parametres, qu'il a anterieurement exposee, par l'enonce d'un critere geometrique de stabilite, relatif aux regimes forces d'un systeme non lineaire. Il obtient, par deux transformations geometriques simples du diagramme, les separatrices qui delimitent les zones de stabilite. (auteur)

  5. The assessing the economic stability of the agricultural organizations of the Kemerovo region

    Directory of Open Access Journals (Sweden)

    Sekacheva Vera Mikhailovna

    2014-08-01

    Full Text Available The main aspects of the essence of economic stability analyzed in this article. The authors define the concept, the problems and the basic criteria for assessing the economic sustainability of the agricultural organizations of the Kemerovo region.

  6. Original Experimental Approach for Assessing Transport Fuel Stability.

    Science.gov (United States)

    Bacha, Kenza; Ben Amara, Arij; Alves Fortunato, Maira; Wund, Perrine; Veyrat, Benjamin; Hayrault, Pascal; Vannier, Axel; Nardin, Michel; Starck, Laurie

    2016-10-21

    The study of fuel oxidation stability is an important issue for the development of future fuels. Diesel and kerosene fuel systems have undergone several technological changes to fulfill environmental and economic requirements. These developments have resulted in increasingly severe operating conditions whose suitability for conventional and alternative fuels needs to be addressed. For example, fatty acid methyl esters (FAMEs) introduced as biodiesel are more prone to oxidation and may lead to deposit formation. Although several methods exist to evaluate fuel stability (induction period, peroxides, acids, and insolubles), no technique allows one to monitor the real-time oxidation mechanism and to measure the formation of oxidation intermediates that may lead to deposit formation. In this article, we developed an advanced oxidation procedure (AOP) based on two existing reactors. This procedure allows the simulation of different oxidation conditions and the monitoring of the oxidation progress by the means of macroscopic parameters, such as total acid number (TAN) and advanced analytical methods like gas chromatography coupled to mass spectrometry (GC-MS) and Fourier Transform Infrared - Attenuated Total Reflection (FTIR-ATR). We successfully applied AOP to gain an in-depth understanding of the oxidation kinetics of a model molecule (methyl oleate) and commercial diesel and biodiesel fuels. These developments represent a key strategy for fuel quality monitoring during logistics and on-board utilization.

  7. Methods for assessing the stability of slopes during earthquakes-A retrospective

    Science.gov (United States)

    Jibson, R.W.

    2011-01-01

    During the twentieth century, several methods to assess the stability of slopes during earthquakes were developed. Pseudostatic analysis was the earliest method; it involved simply adding a permanent body force representing the earthquake shaking to a static limit-equilibrium analysis. Stress-deformation analysis, a later development, involved much more complex modeling of slopes using a mesh in which the internal stresses and strains within elements are computed based on the applied external loads, including gravity and seismic loads. Stress-deformation analysis provided the most realistic model of slope behavior, but it is very complex and requires a high density of high-quality soil-property data as well as an accurate model of soil behavior. In 1965, Newmark developed a method that effectively bridges the gap between these two types of analysis. His sliding-block model is easy to apply and provides a useful index of co-seismic slope performance. Subsequent modifications to sliding-block analysis have made it applicable to a wider range of landslide types. Sliding-block analysis provides perhaps the greatest utility of all the types of analysis. It is far easier to apply than stress-deformation analysis, and it yields much more useful information than does pseudostatic analysis. ?? 2010.

  8. Photo stability Assessment in Amorphous-Silicon Solar Cells

    International Nuclear Information System (INIS)

    Gandia, J. J.; Carabe, J.; Fabero, F.; Jimenez, R.; Rivero, J. M.

    1999-01-01

    The present status of amorphous-silicon-solar-cell research and development at CIEMAT requires the possibility to characterise the devices prepared from the point of view of their stability against sunlight exposure. Therefore a set of tools providing such a capacity has been developed. Together with an introduction to photovoltaic applications of amorphous silicon and to the photodegradation problem, the present work describes the process of setting up these tools. An indoor controlled photodegradation facility has been designed and built, and a procedure has been developed for the measurement of J-V characterisation in well established conditions. This method is suitable for all kinds of solar cells, even for those for which no model is still available. The photodegradation and characterisation of some cells has allowed to validate both the new testing facility and method. (Author) 14 refs

  9. Study on heavy duty truck stability control by braking force control; Seidoryoku seigyo ni yoru truck no sharyo kyodo anteika ni taisuru ichikosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, K; Shinjo, H; Harada, M; Ohata, K; Sakata, K [Mitsubishi Motors Corp., Tokyo (Japan)

    1997-10-01

    Now a days we are discussing about the vehicle stability control system which freely controls the braking force of each wheel to apply the yaw t and decelerate the vehicle. The system drastically improve the vehicle cornering performance and stabilize the vehicle behavior in its critical area. This paper discusses a point to notice in case of applying this technique for heavy duty trucks, and describes the possibility of the stabilization for vehicle cornering behavior about heavy duty truck. 3 refs., 10 figs., 2 tabs.

  10. Assessment of Slope Stability of Various Cut Slopes with Effects of Weathering by Using Slope Stability Probability Classification (SSPC)

    Science.gov (United States)

    Ersöz, Timur; Topal, Tamer

    2017-04-01

    Rocks containing pore spaces, fractures, joints, bedding planes and faults are prone to weathering due to temperature differences, wetting-drying, chemistry of solutions absorbed, and other physical and chemical agents. Especially cut slopes are very sensitive to weathering activities because of disturbed rock mass and topographical condition by excavation. During and right after an excavation process of a cut slope, weathering and erosion may act on this newly exposed rock material. These acting on the material may degrade and change its properties and the stability of the cut slope in its engineering lifetime. In this study, the effect of physical and chemical weathering agents on shear strength parameters of the rocks are investigated in order to observe the differences between weathered and unweathered rocks. Also, slope stability assessment of cut slopes affected by these weathering agents which may disturb the parameters like strength, cohesion, internal friction angle, unit weight, water absorption and porosity are studied. In order to compare the condition of the rock materials and analyze the slope stability, the parameters of weathered and fresh rock materials are found with in-situ tests such as Schmidt hammer and laboratory tests like uniaxial compressive strength, point load and direct shear. Moreover, slake durability and methylene blue tests are applied to investigate the response of the rock to weathering and presence of clays in rock materials, respectively. In addition to these studies, both rock strength parameters and any kind of failure mechanism are determined by probabilistic approach with the help of SSPC system. With these observations, the performances of the weathered and fresh zones of the cut slopes are evaluated and 2-D slope stability analysis are modeled with further recommendations for the cut slopes. Keywords: 2-D Modeling, Rock Strength, Slope Stability, SSPC, Weathering

  11. Supplemental Environmental Assessment for the Mid-Bay Bridge Connector Phases 2 and 3, Eglin Air Force Base, Florida

    Science.gov (United States)

    2010-08-03

    D. Rodriigue;c 96 CEGICEVS PEPARTMENT OF THE AWR FORCE HEADQUARTERS 96TH AIR &ASE WING (AFMC) EGUN AJR FORCE BASE, FLORIDA 501 Deleon Stteet...Supplemental Environmental Assessment Maria D. Rodriguez 96CEG/CEVS DEPARTMENT OF THE AiR FORCE HEADQUARTERS 96Tit AIR BASE WING (I’ fMC) EGUN AIR FORCE...BASE WING (AFMC) EGUN AIR fORCE BASE, FLORIDA Historic Preservation Specialist Old Post Office Building 1100 Pennsylvania Avenue, NW, Suite 803

  12. Final Environmental Assessment for the Runway Extension and New Parking Apron at Tyndall Air Force Base, Florida

    National Research Council Canada - National Science Library

    2004-01-01

    The Air Force prepared an Environmental Assessment (EA) of the potential environmental consequences of constructing a new heavy parking apron and runway extension at Tyndall Air Force Base (AFB), Florida...

  13. Reliability assessment of slender concrete columns at the stability failure

    Science.gov (United States)

    Valašík, Adrián; Benko, Vladimír; Strauss, Alfred; Täubling, Benjamin

    2018-01-01

    The European Standard for designing concrete columns within the use of non-linear methods shows deficiencies in terms of global reliability, in case that the concrete columns fail by the loss of stability. The buckling failure is a brittle failure which occurs without warning and the probability of its formation depends on the columns slenderness. Experiments with slender concrete columns were carried out in cooperation with STRABAG Bratislava LTD in Central Laboratory of Faculty of Civil Engineering SUT in Bratislava. The following article aims to compare the global reliability of slender concrete columns with slenderness of 90 and higher. The columns were designed according to methods offered by EN 1992-1-1 [1]. The mentioned experiments were used as basis for deterministic nonlinear modelling of the columns and subsequent the probabilistic evaluation of structural response variability. Final results may be utilized as thresholds for loading of produced structural elements and they aim to present probabilistic design as less conservative compared to classic partial safety factor based design and alternative ECOV method.

  14. Stability and forcing of the Iceland-Faroe inflow of water, heat, and salt to the Arctic

    Directory of Open Access Journals (Sweden)

    B. Hansen

    2010-12-01

    Full Text Available The flow of Atlantic water across the Greenland-Scotland Ridge (Atlantic inflow is critical for conditions in the Nordic Seas and Arctic Ocean by importing heat and salt. Here, we present a decade-long series of measurements from the Iceland-Faroe inflow branch (IF-inflow, which carries almost half the total Atlantic inflow. The observations show no significant trend in volume transport of Atlantic water, but temperature and salinity increased during the observational period. On shorter time scales, the observations show considerable variations but no statistically significant seasonal variation is observed and even weekly averaged transport values were consistently uni-directional from the Atlantic into the Nordic Seas. Combining transport time-series with sea level height from satellite altimetry and wind stress reveals that the force driving the IF-inflow across the topographic barrier of the Ridge is mainly generated by a pressure gradient that is due to a continuously maintained low sea level in the Southern Nordic Seas. This implies that the relative stability of the IF-inflow derives from the processes that lower the sea level by generating outflow from the Nordic Seas, especially the thermohaline processes that generate overflow. The IF-inflow is an important component of the system coupling the Arctic region to the North Atlantic through the thermohaline circulation, which has been predicted to weaken in the 21st century. Our observations show no indication of weakening.

  15. Assessing Tuition- and Debt-Free Higher Education. NASFAA Task Force Report

    Science.gov (United States)

    National Association of Student Financial Aid Administrators, 2017

    2017-01-01

    The Assessing Tuition- and Debt-Free Higher Education Task Force was convened in July 2016. Charged by the National Association of Student Financial Aid Administrators's (NASFAA's) Board of Directors with evaluating the existing landscape of state and local promise programs with a focus on scaling such models to the national level, the task force…

  16. A comparative assessment of forces and moments generated by lingual and conventional brackets

    NARCIS (Netherlands)

    Sifakakis, I.; Pandis, N.; Makou, M.; Katsaros, C.; Eliades, T.; Bourauel, C.

    2013-01-01

    The aim of this study was to assess the effect of bracket type on the labiopalatal forces and moments generated in the sagittal plane. Incognito lingual brackets (3M Unitek), STb lingual brackets (Light Lingual System; ORMCO), and conventional 0.018 inch slot brackets (Gemini; 3M Unitek) were bonded

  17. Bioassessment in nonperennial streams: Hydrologic stability influences assessment validity

    Science.gov (United States)

    Mazor, R. D.; Stein, E. D.; Schiff, K.; Ode, P.; Rehn, A.

    2011-12-01

    Nonperennial streams pose a challenge for bioassessment, as assessment tools developed in perennial streams may not work in these systems. For example, indices of biotic integrity (IBIs) developed in perennial streams may give improper indications of impairment in nonperennial streams, or may be unstable. We sampled benthic macroinvertebrates from 12 nonperennial streams in southern California. In addition, we deployed loggers to obtain continuous measures of flow. 3 sites were revisited over 2 years. For each site, we calculated several metrics, IBIs, and O/E scores to determine if assessments were consistent and valid throughout the summer. Hydrology varied widely among the streams, with several streams drying between sampling events. IBIs suggested good ecological health at the beginning of the study, but declined sharply at some sites. Multivariate ordination suggested that, despite differences among sites, changes in community structure were similar, with shifts from Ephemeroptera, Plecoptera, and Trichoptera to Coleoptera and more tolerant organisms. Site revisits revealed a surprising level of variability, as 2 of the 3 revisited sites had perennial or near-perennial flow in the second year of sampling. IBI scores were more consistent in streams with stable hydrographs than in those with strongly intermittent hydrographs. These results suggest that nonperennial streams can be monitored successfully, but they may require short index periods and distinct metrics from those used in perennial streams. In addition, better approaches to mapping nonperennial streams are required.

  18. Final Environmental Assessment for the California Space Center at Vandenberg Air Force Base, California

    Science.gov (United States)

    2010-06-02

    rooted , mesophylic plant species that Chapter 3. Affected Environment Final Environmental Assessment - California Space Center, Vandenberg Air...Chapter 3. Affected Environment 3-12 Final Environmental Assessment - California Space Center, Vandenberg Air Force Base the root and debris zone of the...protruding objects, slippery soils or mud, and biological hazards including vegetation (i.e. poison oak and stinging nettle ), animals (i.e. insects

  19. Modeling and Stability Assessment of Single-Phase Grid Synchronization Techniques

    DEFF Research Database (Denmark)

    Golestan, Saeed; Guerrero, Josep M.; Vasquez, Juan

    2018-01-01

    (GSTs) is of vital importance. This task is most often based on obtaining a linear time-invariant (LTI) model for the GST and applying standard stability tests to it. Another option is modeling and dynamics/stability assessment of GSTs in the linear time-periodic (LTP) framework, which has received...... a very little attention. In this letter, the procedure of deriving the LTP model for single-phase GSTs is first demonstrated. The accuracy of the LTP model in predicting the GST dynamic behavior and stability is then evaluated and compared with that of the LTI one. Two well-known single-phase GSTs, i...

  20. GECM-Based Voltage Stability Assessment Using Wide-Area Synchrophasors

    OpenAIRE

    Heng-Yi Su; Tzu-Yi Liu

    2017-01-01

    Voltage instability is a crucial issue in the secure operation of power grids. Several methods for voltage stability assessment were presented. Some of them are highly computationally intensive, while others are reported not to work properly under all circumstances. This paper proposes a new methodology based on the generator equivalent circuit model (GECM) and the phasor measurement unit (PMU) technology for online voltage stability monitoring of a power grid. First, the proposed methodology...

  1. A Simple Measure to Assess Hyperinflation and Air Trapping: 1-Forced Expiratory Volume in Three Second / Forced Vital Capacity

    Directory of Open Access Journals (Sweden)

    Sermin Börekçi

    2017-04-01

    Full Text Available Background: Several recent studies have suggested that 1 minus-forced expiratory volume expired in 3 seconds / forced vital capacity (1-FEV3/FVC may be an indicator of distal airway obstruction and a promising measure to evaluate small airways dysfunction. Aims: To investigate the associations of 1-FEV3/FVC with the spirometric measures and lung volumes that assess small airways dysfunction and reflects hyperinflation and air trapping. Study Design: Retrospective cross-sectional study. Methods: Retrospective assessment of a total of 1110 cases who underwent body plethysmographic lung volume estimations between a time span from 2005 to 2012. Patients were assigned into two groups: firstly by FEV1/FVC (FEV1/FVC <70% vs. FEV1/FVC ≥70%; secondly by FEV3/FVC < lower limits of normal (LLN (FEV3/FVC < LLN vs. FEV3/FVC ≥ LLN. Spirometric indices and lung volumes measured by whole-body plethysmography were compared in groups. Also the correlation of spirometric indices with measured lung volumes were assessed in the whole-study population and in subgroups stratified according to FEV1/FVC and FEV3/FVC. Results: Six hundred seven (54.7% were male and 503 (45.3% were female, with a mean age of 52.5±15.6 years. Mean FEV3/FVC and 1-FEV3/FVC were 87.05%, 12.95%, respectively. The mean 1-FEV3/FVC was 4.9% in the FEV1/FVC ≥70% group (n=644 vs. 24.1% in the FEV1/FVC <70% group (n=466. A positive correlation was found between 1-FEV3/FVC and residual volume (r=0.70; p<0.0001, functional residual capacity-pleth (r=0.61; p<0.0001, and total lung capacity (r=0.47; p<0.0001. 1-FEV3/FVC was negatively correlated with forced expiratory flow25-75 (r=−0.84; p<0.0001. The upper limit of 95% confidence interval for 1-FEV3/FVC was 13.7%. 1-FEV3/FVC showed significant correlations with parameters of air trapping and hyperinflation measured by whole-body plethysmography. Importantly, these correlations were higher in study participants with FEV1/FVC <70% or FEV3/FVC

  2. Chronic in vivo stability assessment of carbon fiber microelectrode arrays

    Science.gov (United States)

    Patel, Paras R.; Zhang, Huanan; Robbins, Matthew T.; Nofar, Justin B.; Marshall, Shaun P.; Kobylarek, Michael J.; Kozai, Takashi D. Y.; Kotov, Nicholas A.; Chestek, Cynthia A.

    2016-12-01

    Objective. Individual carbon fiber microelectrodes can record unit activity in both acute and semi-chronic (∼1 month) implants. Additionally, new methods have been developed to insert a 16 channel array of carbon fiber microelectrodes. Before assessing the in vivo long-term viability of these arrays, accelerated soak tests were carried out to determine the most stable site coating material. Next, a multi-animal, multi-month, chronic implantation study was carried out with carbon fiber microelectrode arrays and silicon electrodes. Approach. Carbon fibers were first functionalized with one of two different formulations of PEDOT and subjected to accelerated aging in a heated water bath. After determining the best PEDOT formula to use, carbon fiber arrays were chronically implanted in rat motor cortex. Some rodents were also implanted with a single silicon electrode, while others received both. At the end of the study a subset of animals were perfused and the brain tissue sliced. Tissue sections were stained for astrocytes, microglia, and neurons. The local reactive responses were assessed using qualitative and quantitative methods. Main results. Electrophysiology recordings showed the carbon fibers detecting unit activity for at least 3 months with average amplitudes of ∼200 μV. Histology analysis showed the carbon fiber arrays with a minimal to non-existent glial scarring response with no adverse effects on neuronal density. Silicon electrodes showed large glial scarring that impacted neuronal counts. Significance. This study has validated the use of carbon fiber microelectrode arrays as a chronic neural recording technology. These electrodes have demonstrated the ability to detect single units with high amplitude over 3 months, and show the potential to record for even longer periods. In addition, the minimal reactive response should hold stable indefinitely, as any response by the immune system may reach a steady state after 12 weeks.

  3. Assessing the relative stabilities of engineered hemoglobins using electrospray mass spectrometry.

    Science.gov (United States)

    Apostol, I

    1999-07-15

    An ion trap mass spectrometer equipped with an electrospray source was used to examine the relative thermodynamic stabilities of various hemoglobins with respect to both tetramer dissociation and hemin dissociation. The results demonstrated that the stability of hemoglobin molecules can be differentiated by the amount of applied collision-induced dissociation (CID) energy necessary to break up the intact tetramer into its constituent globins. The stability of the intact tetramer was affected by single mutations in the beta-globins. The stabilities of the constituent hologlobins were assessed via trap CID of selected ions. The results demonstrated the importance of the contributions of the hologlobin components to the stability of the intact tetramer. Genetic fusion of two alpha-globins, through the introduction of a single glycine residue between the C-terminus of one alpha-chain and the N-terminus of the second, significantly increased the stability of the hemoglobin pseudo-tetramer. Chemical crosslinking of the beta-globins in addition to genetic fusion of alpha-globins further stabilized the hemoglobin molecule. A dihemoglobin molecule produced by the genetic fusion of two di-alpha-globins with a flexible linker demonstrated a decreased stability relative to the corresponding monohemoglobin. Copyright 1999 Academic Press.

  4. Effects of electric field and Coriolis force on electrohydrodynamic stability of poorly conducting couple stress parallel fluid flow in a channel

    International Nuclear Information System (INIS)

    Shankar, B.M.; Rudraiah, N.

    2013-01-01

    The linear stability of electrohydrodynamic poorly conducting couple stress viscous parallel fluid flow in a channel is studied in the presence of a non-uniform transverse electric field and Coriolis force using energy method and supplemented with Galerkin Technique. The sufficient condition for stability is obtained for sufficiently small values of the Reynolds number, R e . From this condition we show that strengthening or weakening of the stability criterion is dictated by the values of the strength of electric field, the coefficient of couple stress fluid and independent of Taylor number. In particular, it is shown that the interaction of electric field with couple stress is more effective in stabilizing the poorly conducting couple stress fluid compared to that in an ordinary Newtonian viscous fluid. (author)

  5. Investigation on forces in frictional kinematic pairs to assess their influence on shock absorber characteristics

    Directory of Open Access Journals (Sweden)

    Janusz GARDULSKI

    2008-01-01

    Full Text Available In telescopic shock absorbers there are two kinematic pairs where dry,semi-dry or fluid friction is most likely to occur. Higher values of friction forces are noted in piston rod-slideway pair due to its sealing function and consequently worse lubricating conditions. The aim of the tests was to assess the influence of forces occurring in frictional kinematic pairs on damping characteristics of shock absorbers. The tests were performed on new and fluid-free shock absorbers for various working strokes and various extortion frequencies.

  6. Intraoperative CT in the assessment of posterior wall acetabular fracture stability.

    Science.gov (United States)

    Cunningham, Brian; Jackson, Kelly; Ortega, Gil

    2014-04-01

    Posterior wall acetabular fractures that involve 10% to 40% of the posterior wall may or may not require an open reduction and internal fixation. Dynamic stress examination of the acetabular fracture under fluoroscopy has been used as an intraoperative method to assess joint stability. The aim of this study was to demonstrate the value of intraoperative ISO computed tomography (CT) examination using the Siemens ISO-C imaging system (Siemens Corp, Malvern, Pennsylvania) in the assessment of posterior wall acetabular fracture stability during stress examination under anesthesia. In 5 posterior wall acetabular fractures, standard fluoroscopic images (including anteroposterior pelvis and Judet radiographs) with dynamic stress examinations were compared with the ISO-C CT imaging system to assess posterior wall fracture stability during stress examination. After review of standard intraoperative fluoroscopic images under dynamic stress examination, all 5 cases appeared to demonstrate posterior wall stability; however, when the intraoperative images from the ISO-C CT imaging system demonstrated that 1 case showed fracture instability of the posterior wall segment during stress examination, open reduction and internal fixation was performed. The use of intraoperative ISO CT imaging has shown an initial improvement in the surgeon's ability to assess the intraoperative stability of posterior wall acetabular fractures during stress examination when compared with standard fluoroscopic images. Copyright 2014, SLACK Incorporated.

  7. ASSESSMENT OF TECHNETIUM LEACHABILITY IN CEMENT STABILIZED BASIN 43 GROUNDWATER BRINE

    International Nuclear Information System (INIS)

    COOKE GA; DUNCAN JB; LOCKREM LL

    2008-01-01

    This report is an initial report on the laboratory effort executed under RPP-PLAN-33338, Test Plan for the Assessment of Technetium Leachability in Cement-Stabilized Basin 43 Groundwater Brine. This report delineates preliminary data obtained under subcontract 21065, release 30, from the RJ Lee Group, Inc., Center for Laboratory Sciences. The report is predicated on CLS RPT-816, Draft Report: Assessment of Technetium Leachability in Cement Stabilized Basin 43 Groundwater Brine. This document will be revised on receipt of the final RJ Lee Group, Inc., Center for Laboratory Sciences report, which will contain data subjected to quality control and quality assurance criteria

  8. Passivity-Based Stability Assessment of Grid-Connected VSCs - An Overview

    DEFF Research Database (Denmark)

    Harnefors, Lennart; Wang, Xiongfei; Yepes, Alejandro G.

    2016-01-01

    The interconnection stability of a grid-connected voltage-source converter (VSC) can be assessed by the passivity properties of the VSC input admittance. If critical grid resonances fall within regions where the input admittance acts passively, i.e., has nonnegative real part, then their destabil......The interconnection stability of a grid-connected voltage-source converter (VSC) can be assessed by the passivity properties of the VSC input admittance. If critical grid resonances fall within regions where the input admittance acts passively, i.e., has nonnegative real part...

  9. Evaluation of HVDC interconnection models for considering its impact in real-time voltage stability assessment

    DEFF Research Database (Denmark)

    Perez, Angel; Jóhannsson, Hjörtur; Lund, P.

    2015-01-01

    An approach to evaluate the HVDC interconnectionsmodels to be used in real-time voltage stability assessment is proposed.The existing models for the HVDC interconnections, thatare based on voltage source converter, were studied selecting theones that are suitable for its application in Thevenin...... equivalent ´methods for voltage stability assessment. The proposed methodis to evaluate the validity of the models by using synthetizedPMU measurements from simulations and from PMUs connectedto the danish system. Wide-area measurements are used toestimate the HVDC model parameters which are needed...

  10. A rapid stability assessment of China's IGS sites after the Ms7. 0 Lushan earthquake

    Directory of Open Access Journals (Sweden)

    Meng Jie

    2013-05-01

    Full Text Available A rapid and accurate assessment of the stability of surveying and mapping reference points is important for post – disaster rescue, disaster relief and reconstruction activities. Using Precise Point Positioning (PPP technology, a rapid assessment of the stability of the IGS sites in China was performed after the Ms 7. 0 Lushan earthquake using rapid precise ephemeris and rapid precise satellite clock products. The results show that the earthquake had a very small impact and did not cause significant permanent deformation at the IGS sites. Most of the sites were unaffected and remained stable after the earthquake.

  11. Dynamic stability analysis of circular arch subjected to follower forces with small disturbances; Judo kaju wo ukeru enkei arch no yuran ni yoru doteki kyodo to anteisei kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Fukuchi, N.; Okada, K. [Kyushu University, Fukuoka (Japan). Faculty of Engineering; Hirano, Y. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

    1997-09-04

    This paper describes the deformation and dynamic stability of circular arch subjected to follower forces in a submerged membrane type marine structure reinforced by arch frames. Governing equations for finite deformations of the circular arch subjected to follower forces are introduced using an embedded curve coordinate, which are formulated by applying Galerkin method. In addition, equations of motion due to small disturbances under given condition of loading are introduced. Based on these equations, dynamic stability of the arch is analyzed by means of Runnge-Kutta-Gill method, to clarify the relationship between disturbances and instability regions and the resulting phenomena. Near the boundary regions of stability, both amplitude and cycle of deformation are greatly affected by the amplitude of disturbances. The dynamic instability is governed by the inverse symmetry primary mode with minimum characteristic frequency which is specific for the circular arch. The dynamic stability has high parameter dependency, and the instability regions have a complicated shapes. Although flattened arch has a smaller static critical load, it provides the dynamic stability against the disturbance. 5 refs., 10 figs.

  12. The force-sensing device region of α-catenin is an intrinsically disordered segment in the absence of intramolecular stabilization of the autoinhibitory form.

    Science.gov (United States)

    Hirano, Yoshinori; Amano, Yu; Yonemura, Shigenobu; Hakoshima, Toshio

    2018-05-01

    Mechanotransduction by α-catenin facilitates the force-dependent development of adherens junctions (AJs) by recruiting vinculin to reinforce actin anchoring of AJs. The α-catenin mechanotransducing action is facilitated by its force-sensing device region that autoinhibits the vinculin-binding site 1 (VBS1). Here, we report the high-resolution structure of the force-sensing device region of α-catenin, which shows the autoinhibited form comprised of helix bundles E, F and G. The cryptic VBS1 is embedded into helix bundle E stabilized by direct interactions with the autoinhibitory region forming helix bundles F and G. Our molecular dissection study showed that helix bundles F and G are stable in solution in each isolated form, whereas helix bundle E that contains VBS1 is unstable and intrinsically disordered in solution in the isolated form. We successfully identified key residues mediating the autoinhibition and produced mutated α-catenins that display variable force sensitivity and autoinhibition. Using these mutants, we demonstrate both in vitro and in vivo that, in the absence of this stabilization, the helix bundle containing VBS1 would adopt an unfolded form, thus exposing VBS for vinculin binding. We provide evidence for importance of mechanotransduction with the intrinsic force sensitivity for vinculin recruitment to adherens junctions of epithelial cell sheets with mutated α-catenins. © 2018 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

  13. An Assessment of Economic Stability under the New European Economic Governance

    Directory of Open Access Journals (Sweden)

    Gheorghe HURDUZEU

    2015-06-01

    Full Text Available The economic crisis, followed by the sovereign debt crisis, resulted in high unemployment, unsustainable public finances and deepening disparities between Euro Area member states, and underlined the necessity of strengthening economic coordination. In order to lessen the effects of the crises, to prevent further deepening of the economic context and the appearance of new similar situations, the European framework was improved by the provisions of the new economic governance. The aim of this paper is to assess the effects regarding macroeconomic stability within Euro Area member states, achieved under the new economic governance framework. In this respect, the first part of the paper consists in an overview of the provisions imposed through the European Semester, the reformed Stability and Growth Pact and the other elements of the new European governance. In order to assess the achievement of economic stability we analyzed data for Southern Euro Area member states, during 2009-2013, as this group of countries registered most issues during 2013. We took into consideration five important indicators, essential in any economy that form the macroeconomic stability pentagon: economic growth rate, unemployment rate, inflation rate, budgetary balance and current account balance. By comparing the area obtained through the macroeconomic stability pentagon, we conclude on meeting one of the main objectives of the new European governance: economic stability.

  14. Transient Stability Assessment of Power System with Large Amount of Wind Power Penetration

    DEFF Research Database (Denmark)

    Liu, Leo; Chen, Zhe; Bak, Claus Leth

    2012-01-01

    Recently, the security and stability of power system with large amount of wind power are the concerned issues, especially the transient stability. In Denmark, the onshore and offshore wind farms are connected to distribution system and transmission system respectively. The control and protection...... methodologies of onshore and offshore wind farms definitely affect the transient stability of power system. In this paper, the onshore and offshore wind farms are modeled in detail in order to assess the transient stability of western Danish power system. Further, the computation of critical clearing time (CCT...... plants, load consumption level and high voltage direct current (HVDC) transmission links are taken into account. The results presented in this paper are able to provide an early awareness of power system security condition of the western Danish power system....

  15. Developing a stability assessment method for power electronics-based microgrids

    Science.gov (United States)

    Austin, Peter M.

    Modern microgrids with microsources and energy storage are dependent on power electronics for control and regulation. Under certain circumstances power electronics can be destabilizing to the system due to an effect called negative incremental impedance. A careful review of the theory and literature on the subject is presented. This includes stability criteria for both AC and DC systems, as well as a discussion on the limitations posed by the analysis. A method to integrate stability assessment with higher-level microgrid architectural design is proposed. Crucial to this is impedance characterization of individual components, which was accomplished through simulation. DC and AC impedance measurement blocks were created in Matlab simulink to automate the process. A detailed switching-level model of a DC microgrid was implemented in simulink, including wind turbine microsource, battery storage, and three phase inverter. Maximum power point tracking (MPPT) was included to maximize the efficiency of the turbine and was implemented through three rectifier alternatives and control schemes. The stability characteristics of each was compared in the final analysis. Impedance data was collected individually from the components and used to assess stability in the system as a whole. The results included the assessment of stability, margin, and unstable operating points to demonstrate the feasibility of the proposed approach.

  16. An Improved On-line Contingency Screening for Power System Transient Stability Assessment

    DEFF Research Database (Denmark)

    Weckesser, Johannes Tilman Gabriel; Jóhannsson, Hjörtur; Glavic, Mevludin

    2017-01-01

    This paper presents a contingency screening method and a framework for its on-line implementation. The proposed method carries out contingency screening and on-line stability assessment with respect to first-swing transient stability. For that purpose, it utilizes the single machine equivalent...... method and aims at improving the prior developed contingency screening approaches. In order to determine vulnerability of the system with respect to a particular contingency, only one time-domain simulation needs to be performed. An early stop criteria is proposed so that in a majority of the cases...... the simulation can be terminated after a few hundred milliseconds of simulated system response. The method's outcome is an assessment of the system's stability and a classification of each considered contingency. The contingencies are categorized by exploiting parameters of an equivalent one machine infinite bus...

  17. 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.

  18. Wide-Area Assessment of Aperiodic Small Signal Rotor Angle Stability in Real-Time

    DEFF Research Database (Denmark)

    Jóhannsson, Hjörtur; Nielsen, Arne Hejde; Østergaard, Jacob

    2013-01-01

    This paper presents the details of a new real-time stability assessment method. The method assesses a particular mechanism of stability: each generator’s capability to generate sufficient steady state electromechanical torque. The lack of sufficient steady state torque causes aperiodic increase...... of multiple operating points is derived in the paper. Finally, results from time-domain simulation of instability scenarios in the Nordic32 test system are presented and results used for testing the assessment method. The results illustrate the method’s capability to efficiently identify the location...... in rotor angle and a loss of synchronism, referred to as aperiodic small signal instability. The paper provides the theoretical background of the method and an analytical assessment criterion. Furthermore, a mathematical mapping of the generators’ operating points that enables informative visualization...

  19. Consistency and Stability of Italian Children's Spelling in Dictation versus Composition Assessments

    Science.gov (United States)

    Bigozzi, Lucia; Tarchi, Christian; Pinto, Giuliana

    2017-01-01

    The purpose of this study was to investigate consistency in spelling skills across 2 different tasks of written production (dictation vs. composition) and stability of performance across 4 different grades. We assessed 2nd, 3rd, 4th, and 5th graders' spelling performance through 4 tasks: 2 dictation tasks (passage and sentences) and 2 composition…

  20. Investigation of the Adaptability of Transient Stability Assessment Methods to Real-Time Operation

    DEFF Research Database (Denmark)

    Weckesser, Johannes Tilman Gabriel; Jóhannsson, Hjörtur; Sommer, Stefan

    2012-01-01

    In this paper, an investigation of the adaptability of available transient stability assessment methods to real-time operation and their real-time performance is carried out. Two approaches based on Lyapunov’s method and the equal area criterion are analyzed. The results allow to determine...

  1. Toward ambulatory balance assessment: Estimating variability and stability from short bouts of gait

    NARCIS (Netherlands)

    van Schooten, K.S.; Rispens, S.M.; Elders, P.J.M.; van Dieen, J.H.; Pijnappels, M.A.G.M.

    2014-01-01

    Stride-to-stride variability and local dynamic stability of gait kinematics are promising measures to identify individuals at increased risk of falling. This study aimed to explore the feasibility of using these metrics in clinical practice and ambulatory assessment, where only a small number of

  2. Evaluation of enhancements to Thevenin equivalent based methods for real-time voltage stability assessment

    DEFF Research Database (Denmark)

    Perez, Angel; Jóhannsson, Hjörtur; Østergaard, Jacob

    2014-01-01

    The possibilities offered by the use of Phasor Measurement Units (PMU) in real - time monitoring provide interesting ways to ensure secure operation of power systems. This paper studies the specific case of voltage stability and the possible improvements to the Thevenin equivalent methods, which...... is applied generally with local measurements. This paper uses the PMU measurements to calculate the grid transformation coefficients to obtain wide - area information. This is achieved by studying the generator's electromo tive force estimated using values in the coefficient transformation matrix...

  3. Final Environmental Assessment Addressing Riparian Restoration and Stabilization at Grand Forks Air Force Base, North Dakota

    Science.gov (United States)

    2012-09-01

    trail ATV use, paintball use, and cutting of young, healthy trees; unmanaged grazing and wildfires; monitoring for insects and disease such as Dutch Elm...maximillianii), jack-in-the-pulpit (Arisaema triphyllum), white violet (Viola canadensis), wood nettle (Laportea canadensis), stinging nettle (Urtica dioica...for insects and disease such as Dutch Elm disease, gypsy moths, tent worms, or other pathogens that could damage the forest health. During

  4. Guidelines and Ethical Considerations for Assessment Center Operations: International Task Force on Assessment Center Guidelines.

    Science.gov (United States)

    Public Personnel Management, 2000

    2000-01-01

    This update of the International Personnel Management Association's guidelines for organizational psychologists, human resource management specialists, and others addresses elements of assessment centers, policy statements, assessor training, informed participation, and participants' rights. (SK)

  5. 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.

  6. The influence of physical and physiological cues on atomic force microscopy-based cell stiffness assessment.

    Science.gov (United States)

    Chiou, Yu-Wei; Lin, Hsiu-Kuan; Tang, Ming-Jer; Lin, Hsi-Hui; Yeh, Ming-Long

    2013-01-01

    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.

  7. Physiological and methodological aspects of rate of force development assessment in human skeletal muscle.

    Science.gov (United States)

    Rodríguez-Rosell, David; Pareja-Blanco, Fernando; Aagaard, Per; González-Badillo, Juan José

    2017-12-20

    Rate of force development (RFD) refers to the ability of the neuromuscular system to increase contractile force from a low or resting level when muscle activation is performed as quickly as possible, and it is considered an important muscle strength parameter, especially for athletes in sports requiring high-speed actions. The assessment of RFD has been used for strength diagnosis, to monitor the effects of training interventions in both healthy populations and patients, discriminate high-level athletes from those of lower levels, evaluate the impairment in mechanical muscle function after acute bouts of eccentric muscle actions and estimate the degree of fatigue and recovery after acute exhausting exercise. Notably, the evaluation of RFD in human skeletal muscle is a complex task as influenced by numerous distinct methodological factors including mode of contraction, type of instruction, method used to quantify RFD, devices used for force/torque recording and ambient temperature. Another important aspect is our limited understanding of the mechanisms underpinning rapid muscle force production. Therefore, this review is primarily focused on (i) describing the main mechanical characteristics of RFD; (ii) analysing various physiological factors that influence RFD; and (iii) presenting and discussing central biomechanical and methodological factors affecting the measurement of RFD. The intention of this review is to provide more methodological and analytical coherency on the RFD concept, which may aid to clarify the thinking of coaches and sports scientists in this area. © 2017 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  8. Development of a mobile sensor for robust assessment of river bed grain forces

    Science.gov (United States)

    Maniatis, G.; Hoey, T.; Sventek, J.; Hodge, R. A.

    2013-12-01

    The forces experienced by sediment grains at entrainment and during transport, and those exerted on river beds, are significant for the development of river systems and landscape evolution. The assessment of local grain forces has been approached using two different methodologies. The first approach uses static impact sensors at points or cross-sections to measure velocity and/or acceleration. A second approach uses mobile natural or artificial 'smart' pebbles instrumented with inertia micro-sensors for directly measuring the local forces experienced by individual grains. The two approaches have yielded significantly different magnitudes of impact forces. Static sensors (piezoelectric plates connected to accelerometers) temporally smooth the impacts from several grains and infrequently detect the higher forces (up to ×100g) generated by direct single-grain impacts. The second method is currently unable to record the full range of impacts in real rivers due to the low measurement range of the deployed inertia sensors (×3g). Laboratory applications have required only low-range accelerometers, so excluding the magnitude of natural impacts from the design criteria. Here we present the first results from the development of a mobile sensor, designed for the purpose of measuring local grain-forces in a natural riverbed. We present two sets of measurements. The first group presents the calibration of a wide range micro-accelerometer from a set of vertical drop experiments (gravitational acceleration) and further experiments on a shaking table moving with pre-defined acceleration. The second group of measurements are from incipient motion experiments performed in a 9m x0.9m flume (slope 0.001 to 0.018) under steadily increasing discharge. Initially the spherical sensor grain was placed on an artificial surface of hemispheres of identical diameter to the sensor (111mm). Incipient motion was assessed under both whole and half-diameter exposure for each slope. Subsequently

  9. Transient Stability Assessment of Power Systems With Uncertain Renewable Generation: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Villegas Pico, Hugo Nestor [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Aliprantis, Dionysios C. [Purdue University; Lin, Xiaojun [Purdue University

    2017-08-09

    The transient stability of a power system depends heavily on its operational state at the moment of a fault. In systems where the penetration of renewable generation is significant, the dispatch of the conventional fleet of synchronous generators is uncertain at the time of dynamic security analysis. Hence, the assessment of transient stability requires the solution of a system of nonlinear ordinary differential equations with unknown initial conditions and inputs. To this end, we set forth a computational framework that relies on Taylor polynomials, where variables are associated with the level of renewable generation. This paper describes the details of the method and illustrates its application on a nine-bus test system.

  10. Stabilization of emission of CO2: A computable general equilibrium assessment

    International Nuclear Information System (INIS)

    Glomsroed, S.; Vennemo, H.; Johnsen, T.

    1992-01-01

    A multisector computable general equilibrium model is used to study economic development perspectives in Norway if CO 2 emissions were stabilized. The effects discussed include impacts on main macroeconomic indicators and economic growth, sectoral allocation of production, and effects on the market for energy. The impact of other pollutants than CO 2 on emissions is assessed along with the related impact on noneconomic welfare. The results indicate that CO 2 emissions might be stabilized in Norway without dramatically reducing economic growth. Sectoral allocation effects are much larger. A substantial reduction in emissions to air other than CO 2 is found, yielding considerable gains in noneconomic welfare. 25 refs., 6 tabs., 2 figs

  11. Kinematic measures for assessing gait stability in elderly individuals: a systematic review.

    Science.gov (United States)

    Hamacher, D; Singh, N B; Van Dieën, J H; Heller, M O; Taylor, W R

    2011-12-07

    Falls not only present a considerable health threat, but the resulting treatment and loss of working days also place a heavy economic burden on society. Gait instability is a major fall risk factor, particularly in geriatric patients, and walking is one of the most frequent dynamic activities of daily living. To allow preventive strategies to become effective, it is therefore imperative to identify individuals with an unstable gait. Assessment of dynamic stability and gait variability via biomechanical measures of foot kinematics provides a viable option for quantitative evaluation of gait stability, but the ability of these methods to predict falls has generally not been assessed. Although various methods for assessing gait stability exist, their sensitivity and applicability in a clinical setting, as well as their cost-effectiveness, need verification. The objective of this systematic review was therefore to evaluate the sensitivity of biomechanical measures that quantify gait stability among elderly individuals and to evaluate the cost of measurement instrumentation required for application in a clinical setting. To assess gait stability, a comparative effect size (Cohen's d) analysis of variability and dynamic stability of foot trajectories during level walking was performed on 29 of an initial yield of 9889 articles from four electronic databases. The results of this survey demonstrate that linear variability of temporal measures of swing and stance was most capable of distinguishing between fallers and non-fallers, whereas step width and stride velocity prove more capable of discriminating between old versus young (OY) adults. In addition, while orbital stability measures (Floquet multipliers) applied to gait have been shown to distinguish between both elderly fallers and non-fallers as well as between young and old adults, local stability measures (λs) have been able to distinguish between young and old adults. Both linear and nonlinear measures of foot

  12. Local Dynamic Stability Assessment of Motion Impaired Elderly Using Electronic Textile Pants.

    Science.gov (United States)

    Liu, Jian; Lockhart, Thurmon E; Jones, Mark; Martin, Tom

    2008-10-01

    A clear association has been demonstrated between gait stability and falls in the elderly. Integration of wearable computing and human dynamic stability measures into home automation systems may help differentiate fall-prone individuals in a residential environment. The objective of the current study was to evaluate the capability of a pair of electronic textile (e-textile) pants system to assess local dynamic stability and to differentiate motion-impaired elderly from their healthy counterparts. A pair of e-textile pants comprised of numerous e-TAGs at locations corresponding to lower extremity joints was developed to collect acceleration, angular velocity and piezoelectric data. Four motion-impaired elderly together with nine healthy individuals (both young and old) participated in treadmill walking with a motion capture system simultaneously collecting kinematic data. Local dynamic stability, characterized by maximum Lyapunov exponent, was computed based on vertical acceleration and angular velocity at lower extremity joints for the measurements from both e-textile and motion capture systems. Results indicated that the motion-impaired elderly had significantly higher maximum Lyapunov exponents (computed from vertical acceleration data) than healthy individuals at the right ankle and hip joints. In addition, maximum Lyapunov exponents assessed by the motion capture system were found to be significantly higher than those assessed by the e-textile system. Despite the difference between these measurement techniques, attaching accelerometers at the ankle and hip joints was shown to be an effective sensor configuration. It was concluded that the e-textile pants system, via dynamic stability assessment, has the potential to identify motion-impaired elderly.

  13. Median of patient results as a tool for assessment of analytical stability

    DEFF Research Database (Denmark)

    Jørgensen, Lars Mønster; Hansen, Steen Ingemann; Petersen, Per Hyltoft

    2015-01-01

    BACKGROUND: In spite of the well-established external quality assessment and proficiency testing surveys of analytical quality performance in laboratory medicine, a simple tool to monitor the long-term analytical stability as a supplement to the internal control procedures is often needed. METHOD......: Patient data from daily internal control schemes was used for monthly appraisal of the analytical stability. This was accomplished by using the monthly medians of patient results to disclose deviations from analytical stability, and by comparing divergences with the quality specifications for allowable...... analytical bias based on biological variation. RESULTS: Seventy five percent of the twenty analytes achieved on two COBASs INTEGRA 800 instruments performed in accordance with the optimum and with the desirable specifications for bias. DISCUSSION: Patient results applied in analytical quality performance...

  14. Assessment of pipeline stability in the Gulf of Mexico during hurricanes using dynamic analysis

    Directory of Open Access Journals (Sweden)

    Yinghui Tian

    2015-03-01

    Full Text Available Pipelines are the critical link between major offshore oil and gas developments and the mainland. Any inadequate on-bottom stability design could result in disruption and failure, having a devastating impact on the economy and environment. Predicting the stability behavior of offshore pipelines in hurricanes is therefore vital to the assessment of both new design and existing assets. The Gulf of Mexico has a very dense network of pipeline systems constructed on the seabed. During the last two decades, the Gulf of Mexico has experienced a series of strong hurricanes, which have destroyed, disrupted and destabilized many pipelines. This paper first reviews some of these engineering cases. Following that, three case studies are retrospectively simulated using an in-house developed program. The study utilizes the offshore pipeline and hurricane details to conduct a Dynamic Lateral Stability analysis, with the results providing evidence as to the accuracy of the modeling techniques developed.

  15. Advanced controls for stability assessment of solar dynamics space power generation

    Science.gov (United States)

    Momoh, James A.; Anwah, Nnamdi A.

    1995-01-01

    In support of the power requirements for the Space Station Alpha (SSA), a joint program by the U.S. and Russia for a permanently manned space station to be launched into orbit by 1998, a robust control scheme is needed to assure the stability of the rotating machines that will be integrated into the power subsystem. A framework design and systems studies for modeling and analysis is presented. It employs classical d-q axes machine model with voltage/frequency dependent loads. To guarantee that design requirements and necessary trade studies are done, a functional analysis tool CORE is used for the study. This provides us with different control options for stability assessment. Initial studies and recommendations using advanced simulation tools are also presented. The benefits of the stability/control scheme for evaluating future designs and power management are discussed.

  16. Environmental Assessment for the National Museum of the United States Air Force Addition, Wright-Patterson Air Force Base, Ohio

    Science.gov (United States)

    2013-02-01

    AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) United States Air Force 88th...Air Base Wing Wright-Patterson Air Force Base, Ohio 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES...visitors nationwide and from foreign countries. Softball and soccer fields are located adjacent to the Museum grounds and are operated by the 88 Air

  17. Assessment of effect of SSSC stabilizer in different control channels on damping inter-area oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Shakarami, M.R., E-mail: shakarami@iust.ac.i [Centre of Excellence for Power System Automation and Operation, Department of Electrical Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of); Kazemi, A. [Centre of Excellence for Power System Automation and Operation, Department of Electrical Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of)

    2011-03-15

    A static synchronous series compensator (SSSC) is one of the series flexible ac transmission system (FACTS) devices that injects a balanced three-phase voltage in quadrature with the transmission line current. There are two channels for controlling of phase and magnitude of the voltage. When the SSSC is used for damping of inter-area oscillations, a SSSC-based stabilizer can be included in both channels. In this paper, the best location and suitable input control signal for SSSC in order to enhance the damping of inter-area oscillations are selected by residue analysis. A method by quadratic mathematic programming has been presented to the design of the stabilizer. By this method, the effect of the stabilizer in both control channels of the SSSC on damping of inter-area oscillations has been assessed. By considering the gain of stabilizer as a criterion, obtained results from studying on a small and a large multi-machine power system show that the stabilizer in the phase control channel is more effective for damping inter-are oscillations.

  18. Topical gel formulation and stability assessment of platelet lysate based on turbidimetric method

    Directory of Open Access Journals (Sweden)

    Soliman Mohammadi Samani

    2015-06-01

    Full Text Available Platelet-rich growth factors have attracted attentions of scientists and clinical practitioners who are involved in wound healing and regenerative medicine extensively, according to their unprecedented potential of promoting and catalyzing healing process. Platelet-rich growth factors are cost-benefit, available and more stable than recombinant human growth factors. These appealing characteristics have converted PRGF to one of the popular candidates for treatment of variety of wounds. According to these valuable properties, we decided to formulate and assess the effect of different excipients on the stability of such valuable protein based formulations. Different excipients have been chosen according to their effective ness on the stability of proteins and their application in other similar formulations. The stabilizing effect of excipients was evaluated by measuring heat-induced aggregation of growth factors by turbidimetric assay. Glycerol, glycine and dextrose were chosen as stabilizing excipients for these formulations. The results show that dextrose has more stabilizing effect on prevention of heat induced aggregation of the platelet lysate growth factors than glycerol and glycine. All of the formulations also contained antioxidant, chelating agents, preservative and carbopol934 in order to form appropriate gel.

  19. Assessment of changes in gait parameters and vertical ground reaction forces after total hip arthroplasty

    Directory of Open Access Journals (Sweden)

    Bhargava P

    2007-01-01

    Full Text Available The principal objectives of arthroplasty are relief of pain and enhancement of range of motion. Currently, postoperative pain and functional capacity are assessed largely on the basis of subjective evaluation scores. Because of the lack of control inherent in this method it is often difficult to interpret data presented by different observers in the critical evaluation of surgical method, new components and modes of rehabilitation. Gait analysis is a rapid, simple and reliable method to assess functional outcome. This study was undertaken in an effort to evaluate the gait characteristics of patients who underwent arthroplasty, using an Ultraflex gait analyzer. Materials and Methods: The study was based on the assessment of gait and weight-bearing pattern of both hips in patients who underwent total hip replacement and its comparison with an age and sex-matched control group. Twenty subjects of total arthroplasty group having unilateral involvement, operated by posterior approach at our institution with a minimum six-month postoperative period were selected. Control group was age and sex-matched, randomly selected from the general population. Gait analysis was done using Ultraflex gait analyzer. Gait parameters and vertical ground reaction forces assessment was done by measuring the gait cycle properties, step time parameters and VGRF variables. Data of affected limb was compared with unaffected limb as well as control group to assess the weight-bearing pattern. Statistical analysis was done by′t′ test. Results: Frequency is reduced and gait cycle duration increased in total arthroplasty group as compared with control. Step time parameters including Step time, Stance time and Single support time are significantly reduced ( P value < .05 while Double support time and Single swing time are significantly increased ( P value < .05 in the THR group. Forces over each sensor are increased more on the unaffected limb of the THR group as compared to

  20. 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

  1. Interim Analysis of Iraqi Security Force Information Provided by the Department of Defense Report, "Measuring Stability and Security in Iraq"

    National Research Council Canada - National Science Library

    Nguyen, Tinh; Thompson, Charles; Williams, Roger M

    2008-01-01

    .... One indicator being reported is information on the number of Iraqi Security Forces (ISF) authorized (required), assigned (on-the-payroll), and trained. The Special Inspector General for Iraq Reconstruction...

  2. GECM-Based Voltage Stability Assessment Using Wide-Area Synchrophasors

    Directory of Open Access Journals (Sweden)

    Heng-Yi Su

    2017-10-01

    Full Text Available Voltage instability is a crucial issue in the secure operation of power grids. Several methods for voltage stability assessment were presented. Some of them are highly computationally intensive, while others are reported not to work properly under all circumstances. This paper proposes a new methodology based on the generator equivalent circuit model (GECM and the phasor measurement unit (PMU technology for online voltage stability monitoring of a power grid. First, the proposed methodology utilizes synchronized phasor (synchrophasor measurements to determine the impedance parameters of a transmission grid by means of the recursive least squares (RLS algorithm. Furthermore, it incorporates the dynamic models of generators to handle the cases with generator reactive power limit violations. After that, an enhanced voltage stability index with GECMs incorporated is developed for reliable and accurate voltage stability assessment. The proposed methodology was first demonstrated on several standard IEEE power systems, and then applied to a practical power system, the Taiwan power (Taipower system. The test results demonstrate the flexibility and effectiveness of the proposed methodology.

  3. Median of patient results as a tool for assessment of analytical stability.

    Science.gov (United States)

    Jørgensen, Lars Mønster; Hansen, Steen Ingemann; Petersen, Per Hyltoft; Sölétormos, György

    2015-06-15

    In spite of the well-established external quality assessment and proficiency testing surveys of analytical quality performance in laboratory medicine, a simple tool to monitor the long-term analytical stability as a supplement to the internal control procedures is often needed. Patient data from daily internal control schemes was used for monthly appraisal of the analytical stability. This was accomplished by using the monthly medians of patient results to disclose deviations from analytical stability, and by comparing divergences with the quality specifications for allowable analytical bias based on biological variation. Seventy five percent of the twenty analytes achieved on two COBASs INTEGRA 800 instruments performed in accordance with the optimum and with the desirable specifications for bias. Patient results applied in analytical quality performance control procedures are the most reliable sources of material as they represent the genuine substance of the measurements and therefore circumvent the problems associated with non-commutable materials in external assessment. Patient medians in the monthly monitoring of analytical stability in laboratory medicine are an inexpensive, simple and reliable tool to monitor the steadiness of the analytical practice. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. DOD Task Force for Business and Stability Operations in Afghanistan: Review of Selected Expenditures Highlights Serious Management and Oversight Problems

    Science.gov (United States)

    2016-04-15

    execute projects and programs, but rather to advise DOD entities on ways to improve contracting processes and procedures. The memorandum establishing the...Task Force stated, “The Task Force will not be responsible for contracting, but will advise existing DoD contracting offices on improved...including the fact that the AGS did not appear to screen the trainees it nominated , resulting in the majority of the trainees being functionally

  5. Assessing fire impacts on the carbon stability of fire-tolerant forests.

    Science.gov (United States)

    Bennett, Lauren T; Bruce, Matthew J; Machunter, Josephine; Kohout, Michele; Krishnaraj, Saravanan Jangammanaidu; Aponte, Cristina

    2017-12-01

    The carbon stability of fire-tolerant forests is often assumed but less frequently assessed, limiting the potential to anticipate threats to forest carbon posed by predicted increases in forest fire activity. Assessing the carbon stability of fire-tolerant forests requires multi-indicator approaches that recognize the myriad ways that fires influence the carbon balance, including combustion, deposition of pyrogenic material, and tree death, post-fire decomposition, recruitment, and growth. Five years after a large-scale wildfire in southeastern Australia, we assessed the impacts of low- and high-severity wildfire, with and without prescribed fire (≤10 yr before), on carbon stocks in multiple pools, and on carbon stability indicators (carbon stock percentages in live trees and in small trees, and carbon stocks in char and fuels) in fire-tolerant eucalypt forests. Relative to unburned forest, high-severity wildfire decreased short-term (five-year) carbon stability by significantly decreasing live tree carbon stocks and percentage stocks in live standing trees (reflecting elevated tree mortality), by increasing the percentage of live tree carbon in small trees (those vulnerable to the next fire), and by potentially increasing the probability of another fire through increased elevated fine fuel loads. In contrast, low-severity wildfire enhanced carbon stability by having negligible effects on aboveground stocks and indicators, and by significantly increasing carbon stocks in char and, in particular, soils, indicating pyrogenic carbon accumulation. Overall, recent preceding prescribed fire did not markedly influence wildfire effects on short-term carbon stability at stand scales. Despite wide confidence intervals around mean stock differences, indicating uncertainty about the magnitude of fire effects in these natural forests, our assessment highlights the need for active management of carbon assets in fire-tolerant eucalypt forests under contemporary fire regimes

  6. Developing integrated performance assessment and forecasting the level of financial and economic enterprise stability

    Directory of Open Access Journals (Sweden)

    Khudyakova T.A.

    2017-01-01

    Full Text Available The article deals with the problem of assessing and forecasting the level of financial and economic enterprise stability through the integrated indicators development. Currently, many enterprises operate under variable external environment, which imposes a strict requirement to consider this uncertainty. For the evaluation, analysis and prediction of the sustainability of the enterprise in the conditions of crisis we believe it possible and necessary to use the apparatus of probability theory and mathematical statistics. This problem solution will improve quantitative assessing the financial and economic stability level, forecasting possible scenarios of the enterprise development and, therefore, based on the proactive management principles and adaptation processes will greatly increase their effective functioning, as well as reduce bankruptcy probability.

  7. Forced Adoption of IFRS by Czech Non-Listed Companies: An Assessment of Benefits and Costs

    Directory of Open Access Journals (Sweden)

    David Procházka

    2016-04-01

    Full Text Available The paper deals with the effects of IFRS adoption by a specific group of companies. It focuses on the so-called forced IFRS adopters, which are such private (non-listed companies that (a are forced to adopt the IFRS (because their parent prepares IFRS consolidated statements and simultaneously (b are not permitted by the regulatory framework of a given jurisdiction to apply the IFRS in their individual financial statements on a  voluntary basis. In particular, benefits and costs connected with the forced IFRS adoption by Czech private companies are assessed. The results, based on a  questionnaire survey among affected companies, confirm the intuitive presumption that accounting treatment of certain items significantly differs between Czech GAAP and IFRS, which requires the use of advanced methods for the conversion of financial statements. Regardless of which conversion method is used, perceptions of both benefits and appropriateness of incurred costs vary across entities. The benefit-to-cost ratio for the two most commonly used conversion methods (spreadsheets and dual accounting software is comparable, as the first method generates fewer benefits for lower costs and the second method is connected with more benefits, but at higher costs. Finally, the survey reveals that actual costs of IFRS adoption are higher than the expected costs regardless of the conversion method applied.

  8. Investigation of the Adaptability of Transient Stability Assessment Methods to Real-Time Operation

    OpenAIRE

    Weckesser, Johannes Tilman Gabriel; Jóhannsson, Hjörtur; Sommer, Stefan; Østergaard, Jacob

    2012-01-01

    In this paper, an investigation of the adaptability of available transient stability assessment methods to real-time operation and their real-time performance is carried out. Two approaches based on Lyapunov’s method and the equal area criterion are analyzed. The results allow to determine the runtime of each method with respect to the number of inputs. Furthermore, it allows to identify, which method is preferable in case of changes in the power system such as the integration of distributed ...

  9. Risk Assessment Stability: A Revalidation Study of the Arizona Risk/Needs Assessment Instrument

    Science.gov (United States)

    Schwalbe, Craig S.

    2009-01-01

    The actuarial method is the gold standard for risk assessment in child welfare, juvenile justice, and criminal justice. It produces risk classifications that are highly predictive and that may be robust to sampling error. This article reports a revalidation study of the Arizona Risk/Needs Assessment instrument, an actuarial instrument for juvenile…

  10. Impacts of the aerodynamic force representation on the stability and performance of a galloping-based energy harvester

    Science.gov (United States)

    Javed, U.; Abdelkefi, A.

    2017-07-01

    One of the challenging tasks in the analytical modeling of galloping systems is the representation of the galloping force. In this study, the impacts of using different aerodynamic load representations on the dynamics of galloping oscillations are investigated. A distributed-parameter model is considered to determine the response of a galloping energy harvester subjected to a uniform wind speed. For the same experimental data and conditions, various polynomial expressions for the galloping force are proposed in order to determine the possible differences in the variations of the harvester's outputs as well as the type of instability. For the same experimental data of the galloping force, it is demonstrated that the choice of the coefficients of the polynomial approximation may result in a change in the type of bifurcation, the tip displacement and harvested power amplitudes. A parametric study is then performed to investigate the effects of the electrical load resistance on the harvester's performance when considering different possible representations of the aerodynamic force. It is indicated that for low and high values of the electrical resistance, there is an increase in the range of wind speeds where the response of the energy harvester is not affected. The performed analysis shows the importance of accurately representing the galloping force in order to efficiently design piezoelectric energy harvesters.

  11. Clinician-Reported Outcome Assessments of Treatment Benefit: Report of the ISPOR Clinical Outcome Assessment Emerging Good Practices Task Force.

    Science.gov (United States)

    Powers, John H; Patrick, Donald L; Walton, Marc K; Marquis, Patrick; Cano, Stefan; Hobart, Jeremy; Isaac, Maria; Vamvakas, Spiros; Slagle, Ashley; Molsen, Elizabeth; Burke, Laurie B

    2017-01-01

    A clinician-reported outcome (ClinRO) assessment is a type of clinical outcome assessment (COA). ClinRO assessments, like all COAs (patient-reported, observer-reported, or performance outcome assessments), are used to 1) measure patients' health status and 2) define end points that can be interpreted as treatment benefits of medical interventions on how patients feel, function, or survive in clinical trials. Like other COAs, ClinRO assessments can be influenced by human choices, judgment, or motivation. A ClinRO assessment is conducted and reported by a trained health care professional and requires specialized professional training to evaluate the patient's health status. This is the second of two reports by the ISPOR Clinical Outcomes Assessment-Emerging Good Practices for Outcomes Research Task Force. The first report provided an overview of COAs including definitions important for an understanding of COA measurement practices. This report focuses specifically on issues related to ClinRO assessments. In this report, we define three types of ClinRO assessments (readings, ratings, and clinician global assessments) and describe emerging good measurement practices in their development and evaluation. The good measurement practices include 1) defining the context of use; 2) identifying the concept of interest measured; 3) defining the intended treatment benefit on how patients feel, function, or survive reflected by the ClinRO assessment and evaluating the relationship between that intended treatment benefit and the concept of interest; 4) documenting content validity; 5) evaluating other measurement properties once content validity is established (including intra- and inter-rater reliability); 6) defining study objectives and end point(s) objectives, and defining study end points and placing study end points within the hierarchy of end points; 7) establishing interpretability in trial results; and 8) evaluating operational considerations for the implementation of

  12. Engaging with farmers as entrepreneurs and partners: experiences with a self-assessment tool for farmer'organisations (FORCE)

    NARCIS (Netherlands)

    Schrader, T.

    2010-01-01

    Governments, donors and companies increasingly perceive small farmers and their organisations as development actors and business partners. A practical self-assessment tool, 'Farmers Organizations Reviewing Capacities and Entrepreneurship' (FORCE), takes up the challenge to translate the recognition

  13. Improved Thévenin equivalent methods for real-time voltage stability assessment

    DEFF Research Database (Denmark)

    Perez, Angel; Jóhannsson, Hjörtur; Østergaard, Jacob

    2016-01-01

    An improved Thévenin equivalent method for real-time voltage stability assessment that uses wide-area information from synchrophasors is proposed. The improvements are a better modeling of the limited synchronous generators, and a processing that anticipates the effect of field current limiters......, before the latter are activated. Several study cases using detailed dynamic simulations of the Nordic test system have been used to assess the performance of the proposed improvements. Their effectiveness is analyzed and, based on the results, their possible application in combination...

  14. Suitability of voltage stability study methods for real-time assessment

    DEFF Research Database (Denmark)

    Perez, Angel; Jóhannsson, Hjörtur; Vancraeyveld, Pieter

    2013-01-01

    This paper analyzes the suitability of existing methods for long-term voltage stability assessment for real-time operation. An overview of the relevant methods is followed with a comparison that takes into account the accuracy, computational efficiency and characteristics when used for security...... assessment. The results enable an evaluation of the run time of each method with respect to the number of inputs. Furthermore, the results assist in identifying which of the methods is most suitable for realtime operation in future power system with production based on fluctuating energy sources....

  15. Light-emitting diode assessment of dentinal defects: the role of presumed extraction forces

    Directory of Open Access Journals (Sweden)

    Marcelo Santos Coelho

    2017-07-01

    Full Text Available Objectives The evaluation of iatrogenic dentinal defects in extracted teeth may be influenced by extraction forces and prolonged dry times. The purpose of this study was to compare the presence of dentinal defects in freshly extracted, periodontally compromised teeth with those in a group of teeth with uncontrolled extraction forces and storage time. Materials and Methods The experimental group consisted of eighteen roots obtained from teeth extracted due to periodontal reasons with class II or III mobility. They were kept in saline and sectioned within 1 hour following extraction. The control group consisted of matched root types obtained from an anonymous tooth collection, consistent with previous dentinal defect studies. The slices were obtained at 3, 6, and 9 mm from the apex. The imaging process exposed all specimens to no more than 60 seconds of dry time. The × 12.8 magnification was used for the 9 mm slices and × 19.2 magnification for the 3 mm and 6 mm slices under light-emitting diode (LED transillumination. The root canal spaces and periodontal tissues were masked to minimize extraneous factors that might influence the evaluators. Chi-square test was used for statistical analysis. Results Dentinal defects were detected in 17% of the experimental group teeth, compared to 61% of control teeth (p = 0.015. Conclusions LED transillumination assessment of freshly extracted roots with class II or III mobility showed smaller number of dentinal defects than roots with uncontrolled storage time and extraction forces. The use of freshly extracted roots with mobility should be considered for future dental defect assessment studies.

  16. The Categorical Stability of Gambling Motives Among Community-Recruited Gamblers: A Longitudinal Assessment.

    Science.gov (United States)

    McGrath, Daniel S; Konkolÿ Thege, Barna

    2018-03-01

    Over the past decade, several motivational models have been proposed to explain the role of motives in gambling disorder. In the model captured by the four-factor Gambling Motives Questionnaire Financial (GMQ-F), gamblers are described as being primarily motivated to gamble for 'coping', 'enhancement', 'social', and 'financial' reasons. Although this model has received significant empirical support; to date, research assessing the role of motives in gambling disorder has been primarily cross-sectional in nature. Thus, the extent to which gambling motives remain stable over time has yet to be explored. In the current study, the stability versus fluidity of self-assessed gambling motives was investigated using the Quinte Longitudinal Study, a longitudinal dataset of gambling behaviour collected over 5 years. Gambling motives of 2795 gamblers were examined over all five annual assessments. The total proportion of gamblers who stayed in the same primary motive category across each of the 5 consecutive assessments was 22%, indicating substantial fluidity in category membership. Substantial movement between categories was seen for each GMQ-F group, as well as an additional group of non-classified motives. Logistic regression analyses suggest that greater resistance to gambling fallacies significantly predicted stability between the baseline assessment and a follow-up 1 year later, but gambling severity did not. Potential limitations in the study design and opportunities for future research are discussed.

  17. Effect of the ion force on the stability constants of the complexes LnCl2+ and LnCl2+ of Europium and Lutetium

    International Nuclear Information System (INIS)

    Fernandez R, E.; Jimenez R, M.; Solache R, M.

    2004-01-01

    A study is presented on the determination of the constants of stability of those complex LnCI 3-n n (where Ln = Eu 3+ and Lu 3+ and n = 1 and 2), by means of a method of extraction with solvent, to constant temperature (303 K) and in means of high ionic force (1- 3M H CI/HCIO 4 ). It is also presented the application of the theory of the specific interaction of ions (SIT) of Bronsted-Guggenheim-Scatchard for the extrapolation of the values to infinite dilution. (Author)

  18. The Health Assessment Longitudinal File imperative: foundation for improving the health of the force.

    Science.gov (United States)

    Kemper, Judith A; Donahue, Donald A; Harris, Judith S

    2003-08-01

    A smaller active duty force and an increased operational tempo have made the Reserve components (RC) essential elements in the accomplishment of the mission of the U.S. Army. One critical factor in meeting mission is maintaining the optimal health of each soldier. Baseline health data about the RC is currently not being collected, even though increasing numbers of reserve soldiers are being activated. The Annual Health Certification and Survey is being developed as a way to meet the RCs' statutory requirement for annual certification of health while at the same time generating and tracking baseline data on each reservist in a longitudinal health file, the Health Assessment Longitudinal File. This article discusses the Annual Health Certification Questionnaire/Health Assessment Longitudinal File, which will greatly enhance the Army's ability to accurately certify the health status of the RC and track health in relation to training, mission activities, and deployment.

  19. Effects of electric field and Coriolis force on electrohydrodynamic stability of poorly conducting couple stress parallel fluid flow in a channel

    International Nuclear Information System (INIS)

    Shankar, B.M.; Rudraiah, N.

    2013-01-01

    The effective functioning of microfluidic devices in chemical, electrical and mechanical engineering involving fluidics particularly those having vibrations and petroleum products containing organic, inorganic and other microfluidics require understanding and control of stability of poorly conducting parallel fluid flows. The electrical conductivity, σ, of a poorly conducting fluidics, increases with the temperature and the concentration of freely suspended particles like RBC, WBC and so on in the blood, the hylauronic acid (HA) and nutrients of synovial fluid in synovial joints will spin producing microrotation, forming micropolar fluid of Eringen. The presence of Deuterium - Tritium (DT) in inertial fusion target (IFT) may also be modeled using micropolar fluid theory of Eringen. A particular case of micropolar fluid theory when microrotation balances with the natural vorticity of a poorly conducting fluidics in the presence of an electric field is called ‘electrohydrodynamic couple stress fluid’ (EHDCF). These EHDCFs exhibit a variation of electrical conductivity, ∇ σ, increasing with temperature and concentration of freely suspended particles, releases the charges from the nuclei forming distribution of charge density, ρ e . These charges induce an electric field, 1 E i . If need be, we can apply an electric field, 1 E a , by embedding electrodes of different potentials at the boundaries. The total electric field, 1 E = 1 E i + 1 E a , produces a current density, 1 J = ρ σ 1 E, according to Ohm’s law and also produces an electric force, 1 F σ = σ 1 E. This current 1 J acts as sensing and the force, 1 F σ acts as actuation. These two properties make the poorly conducting couple stress fluid to act as a smart material. The objective of this paper is to show that EHDCV in presence of coriolis force plays a significant role in controlling the stability of parallel flows which is essential for an effective functioning of machineries that occur in

  20. Performance Comparison of Adaptive Estimation Techniques for Power System Small-Signal Stability Assessment

    Directory of Open Access Journals (Sweden)

    E. A. Feilat

    2010-12-01

    Full Text Available This paper demonstrates the assessment of the small-signal stability of a single-machine infinite- bus power system under widely varying loading conditions using the concept of synchronizing and damping torques coefficients. The coefficients are calculated from the time responses of the rotor angle, speed, and torque of the synchronous generator. Three adaptive computation algorithms including Kalman filtering, Adaline, and recursive least squares have been compared to estimate the synchronizing and damping torque coefficients. The steady-state performance of the three adaptive techniques is compared with the conventional static least squares technique by conducting computer simulations at different loading conditions. The algorithms are compared to each other in terms of speed of convergence and accuracy. The recursive least squares estimation offers several advantages including significant reduction in computing time and computational complexity. The tendency of an unsupplemented static exciter to degrade the system damping for medium and heavy loading is verified. Consequently, a power system stabilizer whose parameters are adjusted to compensate for variations in the system loading is designed using phase compensation method. The effectiveness of the stabilizer in enhancing the dynamic stability over wide range of operating conditions is verified through the calculation of the synchronizing and damping torque coefficients using recursive least square technique.

  1. A PERSPECTIVE ON MILITARY MEDICAL SERVICE ROLE IN STABILIZATION OPERATIONS: EXPANSION OF AIR FORCE MEDICAL SERVICE CAPABILITIES INMEDICAL DIPLOMACY

    Science.gov (United States)

    2017-04-06

    global and regional international organizations (IOs), US and foreign nongovernmental organizations ( NGOs ), and private-sector individuals and for-profit...iv Abstract This research paper advocates that the US military health workers will be more effective in medical diplomacy than their NGO ...organizations (IO), and non-governmental organizations ( NGO ), provided humanitarian assistance to bring social stability to affected regions. In

  2. The driving forces of stability. Exploring the nature of long-term bureaucracy-interest group interactions

    NARCIS (Netherlands)

    Braun, C.H.J.M.

    2013-01-01

    This article explores the nature of long-term interactions between bureaucrats and interest groups by examining two behavioral logics associated with stability in public policy making. In addition to the implicit short-term strategic choices that usually feature in resource-exchange explanations of

  3. The Application of the Accelerated Stability Assessment Program (ASAP) to Quality by Design (QbD) for Drug Product Stability

    OpenAIRE

    Waterman, Kenneth Craig

    2011-01-01

    An isoconversion paradigm, where times in different temperature and humidity-controlled stability chambers are set to provide a fixed degradant level, is shown to compensate for the complex, non-single order kinetics of solid drug products. A humidity-corrected Arrhenius equation provides reliable estimates for temperature and relative humidity effects on degradation rates. A statistical protocol is employed to determine best fits for chemical stability data, which in turn allows for accurate...

  4. Forced expression of stabilized c-Fos in dendritic cells reduces cytokine production and immune responses in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Ryoko; Suzuki, Mayu; Sakaguchi, Ryota; Hasegawa, Eiichi; Kimura, Akihiro; Shichita, Takashi; Sekiya, Takashi [Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjyuku-ku, Tokyo 160-8582 (Japan); Japan Science and Technology Agency, CREST, Chiyoda-ku 102-0075 (Japan); Shiraishi, Hiroshi [Division of Medical Biochemistry, Department of Biomolecular Sciences, Saga Medical School, Saga (Japan); Shimoda, Kouji [Department of Laboratory Animal Center, Keio University School of Medicine, Tokyo (Japan); Yoshimura, Akihiko, E-mail: yoshimura@a6.keio.jp [Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjyuku-ku, Tokyo 160-8582 (Japan); Japan Science and Technology Agency, CREST, Chiyoda-ku 102-0075 (Japan)

    2012-06-29

    Highlights: Black-Right-Pointing-Pointer Dendritic cells expressing stabilized c-Fos produced less inflammatory cytokines. Black-Right-Pointing-Pointer Dendritic cells expressing stabilized c-Fos activated T cells less efficiently. Black-Right-Pointing-Pointer Transgenic mice expressing stabilized c-Fos were resistant to EAE model. -- Abstract: Intracellular cyclic adenosine monophosphate (cAMP) suppresses innate immunity by inhibiting proinflammatory cytokine production by monocytic cells. We have shown that the transcription factor c-Fos is responsible for cAMP-mediated suppression of inflammatory cytokine production, and that c-Fos protein is stabilized by IKK{beta}-mediated phosphorylation. We found that S308 is one of the major phosphorylation sites, and that the S308D mutation prolongs c-Fos halflife. To investigate the role of stabilized c-Fos protein in dendritic cells (DCs) in vivo, we generated CD11c-promoter-deriven c-FosS308D transgenic mice. As expected, bone marrow-derived DCs (BMDCs) from these Tg mice produced smaller amounts of inflammatory cytokines, including TNF-{alpha}, IL-12, and IL-23, but higher levels of IL-10, in response to LPS, than those from wild-type (Wt) mice. When T cells were co-cultured with BMDCs from Tg mice, production of Th1 and Th17 cytokines was reduced, although T cell proliferation was not affected. Tg mice demonstrated more resistance to experimental autoimmune encephalomyelitis (EAE) than did Wt mice. These data suggest that c-Fos in DCs plays a suppressive role in certain innate and adaptive immune responses.

  5. IX - MR Control Chart as a Tool in Assessment of the Cast Iron Properties Stability

    Directory of Open Access Journals (Sweden)

    F. Binczyk

    2007-07-01

    Full Text Available The study offers a statistical assessment of the stability of a technological process of melting and pouring low-carbon grey iron assigned for casting of brake discs. Some specific characteristics were presented that should be taken into consideration when statistical methods are used for technology improvement. The stability of the cast iron melting process was evaluated using data read out from the thermal analysis curve and true data, i.e. the results of spectrometric analysis of the chemical composition and measured values of the mechanical properties. The method for assessment of process stability was discussed on the example of carbon content and Brinell hardness. The examined parameters of the technological process of grey iron melting and casting are independent of each other (the results of carbon content determination in successive melts, the results of hardness measurements, etc.. Therefore, for analysis, the IX - MR type charts were chosen, where single measurements of the selected property (n = 1 serve as a measure of location, while a measure of variability are the, so called, Moving Ranges (MR, which are an absolute value of the difference between the two successive measurements.

  6. Quantitative assessment of intermolecular interactions by atomic force microscopy imaging using copper oxide tips

    Science.gov (United States)

    Mönig, Harry; Amirjalayer, Saeed; Timmer, Alexander; Hu, Zhixin; Liu, Lacheng; Díaz Arado, Oscar; Cnudde, Marvin; Strassert, Cristian Alejandro; Ji, Wei; Rohlfing, Michael; Fuchs, Harald

    2018-05-01

    Atomic force microscopy is an impressive tool with which to directly resolve the bonding structure of organic compounds1-5. The methodology usually involves chemical passivation of the probe-tip termination by attaching single molecules or atoms such as CO or Xe (refs 1,6-9). However, these probe particles are only weakly connected to the metallic apex, which results in considerable dynamic deflection. This probe particle deflection leads to pronounced image distortions, systematic overestimation of bond lengths, and in some cases even spurious bond-like contrast features, thus inhibiting reliable data interpretation8-12. Recently, an alternative approach to tip passivation has been used in which slightly indenting a tip into oxidized copper substrates and subsequent contrast analysis allows for the verification of an oxygen-terminated Cu tip13-15. Here we show that, due to the covalently bound configuration of the terminal oxygen atom, this copper oxide tip (CuOx tip) has a high structural stability, allowing not only a quantitative determination of individual bond lengths and access to bond order effects, but also reliable intermolecular bond characterization. In particular, by removing the previous limitations of flexible probe particles, we are able to provide conclusive experimental evidence for an unusual intermolecular N-Au-N three-centre bond. Furthermore, we demonstrate that CuOx tips allow the characterization of the strength and configuration of individual hydrogen bonds within a molecular assembly.

  7. Nuclear Deterrence in South Asia - an Assessment of Deterrence and Stability in the India-Pakistan Conflict

    OpenAIRE

    Westh, Mark; Juel Giorgio, Maia; Wiegersma, Jakob; Madsen, Tina

    2011-01-01

    This paper offers a coherent assessment of the stability created by nuclear deterrence between India and Pakistan. Our examination posits the neorealist understanding of the stability created by nuclear deterrence in relation to alternative frameworks. To unfold the varying theoretical presuppositions upon which the concept of stability is based, three logically constructed analyses will be undertaken where the theories are explored in relation to empirical data. The Kargil Crisis in 1999 and...

  8. A Multifeature Fusion Approach for Power System Transient Stability Assessment Using PMU Data

    Directory of Open Access Journals (Sweden)

    Yang Li

    2015-01-01

    Full Text Available Taking full advantage of synchrophasors provided by GPS-based wide-area measurement system (WAMS, a novel VBpMKL-based transient stability assessment (TSA method through multifeature fusion is proposed in this paper. First, a group of classification features reflecting the transient stability characteristics of power systems are extracted from synchrophasors, and according to the different stages of the disturbance process they are broken into three nonoverlapped subsets; then a VBpMKL-based TSA model is built using multifeature fusion through combining feature spaces corresponding to each feature subset; and finally application of the proposed model to the IEEE 39-bus system and a real-world power system is demonstrated. The novelty of the proposed approach is that it improves the classification accuracy and reliability of TSA using multifeature fusion with synchrophasors. The application results on the test systems verify the effectiveness of the proposal.

  9. Online Voltage Stability Assessment for Load Areas Based on the Holomorphic Embedding Method

    DEFF Research Database (Denmark)

    Liu, Chengxi; Wang, Bin; Hu, Fengkai

    2018-01-01

    This paper proposes an online steady-state voltage stability assessment scheme to evaluate the proximity to voltage collapse at each bus of a load area. Using a non-iterative holomorphic embedding method (HEM) with a proposed physical germ solution, an accurate loading limit at each load bus can...... be calculated based on online state estimation on the entire load area and a measurement-based equivalent for the external system. The HEM employs a power series to calculate an accurate Power-Voltage (P-V) curve at each load bus and accordingly evaluates the voltage stability margin considering load variations...... and then demonstrated on a load area of the Northeast Power Coordinating Council (NPCC) 48-generator, 140-bus power system....

  10. A statistical analysis to assess the maturity and stability of six composts.

    Science.gov (United States)

    Komilis, Dimitrios P; Tziouvaras, Ioannis S

    2009-05-01

    Despite the long-time application of organic waste derived composts to crops, there is still no universally accepted index to assess compost maturity and stability. The research presented in this article investigated the suitability of seven types of seeds for use in germination bioassays to assess the maturity and phytotoxicity of six composts. The composts used in the study were derived from cow manure, sea weeds, olive pulp, poultry manure and municipal solid waste. The seeds used in the germination bioassays were radish, pepper, spinach, tomato, cress, cucumber and lettuce. Data were analyzed with an analysis of variance at two levels and with pair-wise comparisons. The analysis revealed that composts rendered as phytotoxic to one type of seed could enhance the growth of another type of seed. Therefore, germination indices, which ranged from 0% to 262%, were highly dependent on the type of seed used in the germination bioassay. The poultry manure compost was highly phytotoxic to all seeds. At the 99% confidence level, the type of seed and the interaction between the seeds and the composts were found to significantly affect germination. In addition, the stability of composts was assessed by their microbial respiration, which ranged from approximately 4 to 16g O(2)/kg organic matter and from 2.6 to approximately 11g CO(2)-C/kg C, after seven days. Initial average oxygen uptake rates were all less than approximately 0.35g O(2)/kg organic matter/h for all six composts. A high statistically significant correlation coefficient was calculated between the cumulative carbon dioxide production, over a 7-day period, and the radish seed germination index. It appears that a germination bioassay with radish can be a valid test to assess both compost stability and compost phytotoxicity.

  11. Assessing Temporal Stability for Coarse Scale Satellite Moisture Validation in the Maqu Area, Tibet

    Science.gov (United States)

    Bhatti, Haris Akram; Rientjes, Tom; Verhoef, Wouter; Yaseen, Muhammad

    2013-01-01

    This study evaluates if the temporal stability concept is applicable to a time series of satellite soil moisture images so to extend the common procedure of satellite image validation. The area of study is the Maqu area, which is located in the northeastern part of the Tibetan plateau. The network serves validation purposes of coarse scale (25–50 km) satellite soil moisture products and comprises 20 stations with probes installed at depths of 5, 10, 20, 40, 80 cm. The study period is 2009. The temporal stability concept is applied to all five depths of the soil moisture measuring network and to a time series of satellite-based moisture products from the Advance Microwave Scanning Radiometer (AMSR-E). The in-situ network is also assessed by Pearsons's correlation analysis. Assessments by the temporal stability concept proved to be useful and results suggest that probe measurements at 10 cm depth best match to the satellite observations. The Mean Relative Difference plot for satellite pixels shows that a RMSM pixel can be identified but in our case this pixel does not overlay any in-situ station. Also, the RMSM pixel does not overlay any of the Representative Mean Soil Moisture (RMSM) stations of the five probe depths. Pearson's correlation analysis on in-situ measurements suggests that moisture patterns over time are more persistent than over space. Since this study presents first results on the application of the temporal stability concept to a series of satellite images, we recommend further tests to become more conclusive on effectiveness to broaden the procedure of satellite validation. PMID:23959237

  12. Effect of Perturbations in Coriolis and Centrifugal Forces on the Nonlinear Stability of Equilibrium Point in Robe's Restricted Circular Three-Body Problem

    Directory of Open Access Journals (Sweden)

    P. P. Hallan

    2008-01-01

    Full Text Available The effect of perturbations in Coriolis and cetrifugal forces on the nonlinear stability of the equilibrium point of the Robe's (1977 restricted circular three-body problem has been studied when the density parameter K is zero. By applying Kolmogorov-Arnold-Moser (KAM theory, it has been found that the equilibrium point is stable for all mass ratios μ in the range of linear stability 8/9+(2/3((43/25ϵ1−(10/3ϵ<μ<1, where ϵ and ϵ1 are, respectively, the perturbations in Coriolis and centrifugal forces, except for five mass ratios μ1=0.93711086−1.12983217ϵ+1.50202694ϵ1, μ2 = 0.9672922−0.5542091ϵ+ 1.2443968ϵ1, μ3=0.9459503−0.70458206ϵ+ 1.28436549ϵ1, μ4=0.9660792−0.30152273ϵ + 1.11684064ϵ1, μ5=0.893981−2.37971679ϵ + 1.22385421ϵ1, where the theory is not applicable.

  13. Report on Progress Toward Security and Stability in Afghanistan and United States Plan for Sustaining the Afghanistan National Security Forces

    Science.gov (United States)

    2011-04-01

    105  8.2: INDIA ...2B Afghan Air Force 0 AMoD Education 3 ASOC 0 Gender Integration 0 Personnel Management 2B National Logistics 2B GS G1 2B AMoD AT&L 2B...award nomination package cites her determination to overcome Afghanistan’s cultural stereotypes and to serve in the military “as long as my country

  14. Assessing regional lung mechanics by combining electrical impedance tomography and forced oscillation technique.

    Science.gov (United States)

    Ngo, Chuong; Spagnesi, Sarah; Munoz, Carlos; Lehmann, Sylvia; Vollmer, Thomas; Misgeld, Berno; Leonhardt, Steffen

    2017-08-29

    There is a lack of noninvasive pulmonary function tests which can assess regional information of the lungs. Electrical impedance tomography (EIT) is a radiation-free, non-invasive real-time imaging that provides regional information of ventilation volume regarding the measurement of electrical impedance distribution. Forced oscillation technique (FOT) is a pulmonary function test which is based on the measurement of respiratory mechanical impedance over a frequency range. In this article, we introduce a new measurement approach by combining FOT and EIT, named the oscillatory electrical impedance tomography (oEIT). Our oEIT measurement system consists of a valve-based FOT device, an EIT device, pressure and flow sensors, and a computer fusing the data streams. Measurements were performed on five healthy volunteers at the frequencies 3, 4, 5, 6, 7, 8, 10, 15, and 20 Hz. The measurements suggest that the combination of FOT and EIT is a promising approach. High frequency responses are visible in the derivative of the global impedance index ΔZeit(t,fos). $\\Delta {Z_{{\\text{eit}}}}(t,{f_{{\\text{os}}}}).$ The oEIT signals consist of three main components: forced oscillation, spontaneous breathing, and heart activity. The amplitude of the oscillation component decreases with increasing frequency. The band-pass filtered oEIT signal might be a new tool in regional lung function diagnostics, since local responses to high frequency perturbation could be distinguished between different lung regions.

  15. A Simple Method for Assessing Upper-Limb Force-Velocity Profile in Bench Press.

    Science.gov (United States)

    Rahmani, Abderrahmane; Samozino, Pierre; Morin, Jean-Benoit; Morel, Baptiste

    2018-02-01

    To analyze the reliability and validity of a field computation method based on easy-to-measure data to assess the mean force ([Formula: see text]) and velocity ([Formula: see text]) produced during a ballistic bench-press movement and to verify that the force-velocity profile (F-v) obtained with multiple loaded trials is accurately described. Twelve participants performed ballistic bench presses against various lifted mass from 30% to 70% of their body mass. For each trial, [Formula: see text] and [Formula: see text] were determined from an accelerometer (sampling rate 500 Hz; reference method) and a simple computation method based on upper-limb mass, barbell flight height, and push-off distance. These [Formula: see text] and [Formula: see text] data were used to establish the F-v relationship for each individual and method. A strong to almost perfect reliability was observed between the 2 trials (ICC > .90 for [Formula: see text] and .80 for [Formula: see text], CV%  .80, P push-off distance).

  16. Assessing control of postural stability in community-living older adults using performance-based limits of stability

    DEFF Research Database (Denmark)

    Jbabdi, Myriam; Boissy, Patrice; Hamel, Mathieu

    2008-01-01

    BACKGROUND: Balance disability measurements routinely used to identify fall risks in frail populations have limited value in the early detection of postural stability deficits in community-living older adults. The objectives of the study were to 1) measure performance-based limits of stability (LOS......-session performance variability during multiple trials using the performance-based LOS paradigm. METHODS: Twenty-four healthy community-living older adults (10 men, 14 women) aged between 62 to 85 (mean age +/- sd, 71.5 +/- 6 yrs) participated in the study. Subjects' performance-based LOS were established by asking...

  17. Slope stability and rockfall assessment of volcanic tuffs using RPAS with 2-D FEM slope modelling

    Science.gov (United States)

    Török, Ákos; Barsi, Árpád; Bögöly, Gyula; Lovas, Tamás; Somogyi, Árpád; Görög, Péter

    2018-02-01

    Steep, hardly accessible cliffs of rhyolite tuff in NE Hungary are prone to rockfalls, endangering visitors of a castle. Remote sensing techniques were employed to obtain data on terrain morphology and to provide slope geometry for assessing the stability of these rock walls. A RPAS (Remotely Piloted Aircraft System) was used to collect images which were processed by Pix4D mapper (structure from motion technology) to generate a point cloud and mesh. The georeferencing was made by Global Navigation Satellite System (GNSS) with the use of seven ground control points. The obtained digital surface model (DSM) was processed (vegetation removal) and the derived digital terrain model (DTM) allowed cross sections to be drawn and a joint system to be detected. Joint and discontinuity system was also verified by field measurements. On-site tests as well as laboratory tests provided additional engineering geological data for slope modelling. Stability of cliffs was assessed by 2-D FEM (finite element method). Global analyses of cross sections show that weak intercalating tuff layers may serve as potential slip surfaces. However, at present the greatest hazard is related to planar failure along ENE-WSW joints and to wedge failure. The paper demonstrates that RPAS is a rapid and useful tool for generating a reliable terrain model of hardly accessible cliff faces. It also emphasizes the efficiency of RPAS in rockfall hazard assessment in comparison with other remote sensing techniques such as terrestrial laser scanning (TLS).

  18. Slope stability and rockfall assessment of volcanic tuffs using RPAS with 2-D FEM slope modelling

    Directory of Open Access Journals (Sweden)

    Á. Török

    2018-02-01

    Full Text Available Steep, hardly accessible cliffs of rhyolite tuff in NE Hungary are prone to rockfalls, endangering visitors of a castle. Remote sensing techniques were employed to obtain data on terrain morphology and to provide slope geometry for assessing the stability of these rock walls. A RPAS (Remotely Piloted Aircraft System was used to collect images which were processed by Pix4D mapper (structure from motion technology to generate a point cloud and mesh. The georeferencing was made by Global Navigation Satellite System (GNSS with the use of seven ground control points. The obtained digital surface model (DSM was processed (vegetation removal and the derived digital terrain model (DTM allowed cross sections to be drawn and a joint system to be detected. Joint and discontinuity system was also verified by field measurements. On-site tests as well as laboratory tests provided additional engineering geological data for slope modelling. Stability of cliffs was assessed by 2-D FEM (finite element method. Global analyses of cross sections show that weak intercalating tuff layers may serve as potential slip surfaces. However, at present the greatest hazard is related to planar failure along ENE–WSW joints and to wedge failure. The paper demonstrates that RPAS is a rapid and useful tool for generating a reliable terrain model of hardly accessible cliff faces. It also emphasizes the efficiency of RPAS in rockfall hazard assessment in comparison with other remote sensing techniques such as terrestrial laser scanning (TLS.

  19. Stability Assessment of a System Comprising a Single Machine and Inverter with Scalable Ratings

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Brian B [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lin, Yashen [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Gevorgian, Vahan [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Purba, Victor [University of Minnesota; Dhople, Sairaj [University of Minnesota

    2017-09-28

    From the inception of power systems, synchronous machines have acted as the foundation of large-scale electrical infrastructures and their physical properties have formed the cornerstone of system operations. However, power electronics interfaces are playing a growing role as they are the primary interface for several types of renewable energy sources and storage technologies. As the role of power electronics in systems continues to grow, it is crucial to investigate the properties of bulk power systems in low inertia settings. In this paper, we assess the properties of coupled machine-inverter systems by studying an elementary system comprised of a synchronous generator, three-phase inverter, and a load. Furthermore, the inverter model is formulated such that its power rating can be scaled continuously across power levels while preserving its closed-loop response. Accordingly, the properties of the machine-inverter system can be assessed for varying ratios of machine-to-inverter power ratings and, hence, differing levels of inertia. After linearizing the model and assessing its eigenvalues, we show that system stability is highly dependent on the interaction between the inverter current controller and machine exciter, thus uncovering a key concern with mixed machine-inverter systems and motivating the need for next-generation grid-stabilizing inverter controls.

  20. Assessment of genetic stability in micropropagules of Jatropha curcas genotypes by RAPD and AFLP analysis

    KAUST Repository

    Sharma, Sweta K.

    2011-07-01

    Jatropha curcas (Euphorbiaceae), a drought resistant non edible oil yielding plant, has acquired significant importance as an alternative renewable energy source. Low and inconsistent yields found in field plantations prompted for identification of high yielding clones and their large scale multiplication by vegetative propagation to obtain true to type plants. In the current investigation plantlets of J. curcas generated by axillary bud proliferation (micropropagation) using nodal segments obtained from selected high yielding genotypes were assessed for their genetic stability using Randomly Amplified Polymorphic DNA (RAPD) and Amplified Fragment Length Polymorphism (AFLP) analyses. For RAPD analysis, 21 out of 52 arbitrary decamer primers screened gave clear reproducible bands. In the micropropagated plantlets obtained from the 2nd sub-culture, 4 out of a total of 177 bands scored were polymorphic, but in the 8th and 16th sub-cultures (culture cycle) no polymorphisms were detected. AFLP analysis revealed 0.63%, 0% and 0% polymorphism in the 2nd, 8th and 16th generations, respectively. When different genotypes, viz. IC 56557 16, IC 56557 34 and IC 56557 13, were assessed by AFLP, 0%, 0.31% and 0.47% polymorphisms were found, respectively, indicating a difference in genetic stability among the different genotypes. To the best of our knowledge this is the first report on assessment of genetic stability of micropropagated plantlets in J. curcas and suggests that axillary shoot proliferation can safely be used as an efficient micropropagation method for mass propagation of J. curcas. © 2011 Elsevier B.V.

  1. Comparison of ASSESS neutralization module results with actual small force engagement outcomes

    International Nuclear Information System (INIS)

    Gardner, B.H.; Snell, M.K.; Paulus, W.K.

    1991-01-01

    The ASSESS Neutralization module (Neutralization) is part of the Analytic System and Software for Evaluation of Safeguards and Security (ASSESS), a vulnerability assessment tool. Neutralization models a fire fight between security inspectors (SIs) and adversaries. This paper reports that a comparison has been made between actual outcomes of police and small military engagements and the results predicted by the Neutralization module for similar scenarios. The results of this comparison show a surprising correlation between predicted outcomes (based on numbers of combatants, weapon types, and exposures, etc.) and the actual outcomes of the engagements analyzed. The importance of this analysis is that given the defenders have intelligence on actual adversary characteristics or are protecting against a design basis threat, defense capabilities can be evaluated before an engagement. Results could then be used to develop a favorable probability of a desired outcome. For example, law enforcement agencies are frequently able to compile the number of criminals, types of weaponry, willingness to use force, etc., from analysis of crime scenes

  2. Tactile pavement for guiding walking direction: An assessment of heading direction and gait stability.

    Science.gov (United States)

    Pluijter, Nanda; de Wit, Lieke P W; Bruijn, Sjoerd M; Plaisier, Myrthe A

    2015-10-01

    For maintaining heading direction while walking we heavily rely on vision. Therefore, walking in the absence of vision or with visual attention directed elsewhere potentially leads to dangerous situations. Here we investigated whether tactile information from the feet can be used as a (partial) substitute for vision in maintaining a stable heading direction. If so, participants should be better able to keep a constant heading direction on tactile pavement that indicates directionality than on regular flat pavement. However, such a pavement may also be destabilizing. Thus we asked participants to walk straight ahead on regular pavement, and on tactile pavement (tiles with ridges along the walking direction) while varying the amount of vision. We assessed the effects of the type of pavement as well as the amount of vision on the variability of the heading direction as well as gait stability. Both of these measures were calculated from accelerations and angular velocities recorded from a smartphone attached to the participants trunk. Results showed that on tactile pavement participants had a less variations in their heading direction than on regular pavement. The drawback, however, was that the tactile pavement used in this study decreased gait stability. In sum, tactile pavement can be used as a partial substitute for vision in maintaining heading direction, but it can also decrease gait stability. Future work should focus on designing tactile pavement that does provided directional clues, but is less destabilizing. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Development of a hardware-based AC microgrid for AC stability assessment

    Science.gov (United States)

    Swanson, Robert R.

    As more power electronic-based devices enable the development of high-bandwidth AC microgrids, the topic of microgrid power distribution stability has become of increased interest. Recently, researchers have proposed a relatively straightforward method to assess the stability of AC systems based upon the time-constants of sources, the net bus capacitance, and the rate limits of sources. In this research, a focus has been to develop a hardware test system to evaluate AC system stability. As a first step, a time domain model of a two converter microgrid was established in which a three phase inverter acts as a power source and an active rectifier serves as an adjustable constant power AC load. The constant power load can be utilized to create rapid power flow transients to the generating system. As a second step, the inverter and active rectifier were designed using a Smart Power Module IGBT for switching and an embedded microcontroller as a processor for algorithm implementation. The inverter and active rectifier were designed to operate simultaneously using a synchronization signal to ensure each respective local controller operates in a common reference frame. Finally, the physical system was created and initial testing performed to validate the hardware functionality as a variable amplitude and variable frequency AC system.

  4. Hazard assessment of the stability of a cavern roof along the coastline

    Science.gov (United States)

    Reina, A.; Lollino, P.

    2009-04-01

    This work concerns the hazard assessment about the stability of a large shallow depth cavern, located along the coastline rocky sector of Polignano town (Apulia, Southern Italy) under an intensely urbanised area. This cavern, which lies at the sea level, has been created by a prolonged process of sea erosion within a rock mass formed of a lower stratified limestone mass and an upper Gravina Calcarenite mass. The thickness of the cavern roof, which has a dome shape, is less than 10 metres in the centre. Important buildings, as hotels and private houses, are located just above the top of the roof. Erosion processes have been observed to be still active along the whole cavern due to climate factors and, in particular, to sea salt weathering and sea spray effects. In 2007 a large calcarenite block, 3 m large, fell down from the cavern roof and consequently a field investigation campaign was carried out for a rational stabilization plan in order to understand the current stability conditions of the roof and the potential failure mechanism. Therefore, a thorough geo-structural survey has firstly been carried out, together with laboratory and in-situ testing for measuring the physical and mechanical properties of the calcarenite rock and of the corresponding joints. A monitoring system has also been planned and installed in order to measure the erosional rate and the block displacements in the cavern.

  5. Captopril 25 mg tablets stability assessment in different primary packing materials

    Directory of Open Access Journals (Sweden)

    Flávia Costa Mendes Paiva

    2017-11-01

    Full Text Available Introduction: Packaging is used to provide protection and information, from the production to the administration of a formulation. It is essential to define the primary packaging, for keeping the therapeutic efficacy of drugs, safety of users and for protecting drugs from instability. Objectives: The main objective of this study was to assess the stability of captopril 25 mg tablets in different primary packaging materials. Method: The characterization (IR, DSC and physical tests of the packaging materials used for captopril was carried out prior to the manufacture of tablets. Tablets were also characterized by physical-chemical analysis, comparative dissolution profile and stability studies. Results: The characterization of packaging materials was crucial for understanding the behavior of captopril when packed in each material. Materials with significant barrier, as blisters PVC/PVdC 90 g.m-² and hard aluminum and PVC/PE/PVdC and hard aluminum showed satisfactory results in a second stage, S2. On the contrary, lower barrier materials as blisters PVC/PVdC 40 g.m-² and hard aluminum did not present dissolution analysis S2. Conclusions: The aluminum strip presented the best results. And the batch in glass bottle, although packaged in excellent material, was disapproved in accelerated stability.

  6. Stability of force-free Taylor states in a new version of magnetic flux-averaged magnetohydrodynamics

    International Nuclear Information System (INIS)

    Pfirsch, D.; Sudan, R.N.

    1996-01-01

    It is observed that the recently developed magnetic flux-averaged magnetohydrodynamics (AMHD) [Phys. Plasmas 1, 2488 (1994)] is incompatible with Taylor close-quote s theorem, which states that the lowest-energy state of force-free equilibria based on the conservation of the helicity integral is absolutely stable for vanishingly small resistivity. By a modification of the Lagrangian from which AMHD is derived, a modified version of AMHD that is compatible with Taylor close-quote s theorem is obtained. It also provides an energy principle for examining the linear instability of resistive equilibria, which has a great advantage over resistive MHD. copyright 1996 American Institute of Physics

  7. Joint analysis of epistemic and aleatory uncertainty in stability analysis for geo-hazard assessments

    Science.gov (United States)

    Rohmer, Jeremy; Verdel, Thierry

    2017-04-01

    Uncertainty analysis is an unavoidable task of stability analysis of any geotechnical systems. Such analysis usually relies on the safety factor SF (if SF is below some specified threshold), the failure is possible). The objective of the stability analysis is then to estimate the failure probability P for SF to be below the specified threshold. When dealing with uncertainties, two facets should be considered as outlined by several authors in the domain of geotechnics, namely "aleatoric uncertainty" (also named "randomness" or "intrinsic variability") and "epistemic uncertainty" (i.e. when facing "vague, incomplete or imprecise information" such as limited databases and observations or "imperfect" modelling). The benefits of separating both facets of uncertainty can be seen from a risk management perspective because: - Aleatoric uncertainty, being a property of the system under study, cannot be reduced. However, practical actions can be taken to circumvent the potentially dangerous effects of such variability; - Epistemic uncertainty, being due to the incomplete/imprecise nature of available information, can be reduced by e.g., increasing the number of tests (lab or in site survey), improving the measurement methods or evaluating calculation procedure with model tests, confronting more information sources (expert opinions, data from literature, etc.). Uncertainty treatment in stability analysis usually restricts to the probabilistic framework to represent both facets of uncertainty. Yet, in the domain of geo-hazard assessments (like landslides, mine pillar collapse, rockfalls, etc.), the validity of this approach can be debatable. In the present communication, we propose to review the major criticisms available in the literature against the systematic use of probability in situations of high degree of uncertainty. On this basis, the feasibility of using a more flexible uncertainty representation tool is then investigated, namely Possibility distributions (e

  8. Advanced Techniques for Assessment of Postural and Locomotor Ataxia, Spatial Orientation, and Gaze Stability

    Science.gov (United States)

    Wall, Conrad., III

    1999-01-01

    In addition to adapting to microgravity, major neurovestibular problems of space flight include postflight difficulties with standing, walking, turning corners, and other activities that require stable upright posture and gaze stability. These difficulties inhibit astronauts' ability to stand or escape from their vehicle during emergencies. The long-ter7n goal of the NSBRI is the development of countermeasures to ameliorate the effects of long duration space flight. These countermeasures must be tested with valid and reliable tools. This project aims to develop quantitative, parametric approaches for assessing gaze stability and spatial orientation during normal gait and when gait is perturbed. Two of this year's most important findings concern head fixation distance and ideal trajectory analysis. During a normal cycle of walking the head moves up and down linearly. A simultaneous angular pitching motion of the head keeps it aligned toward an imaginary point in space at a distance of about one meter in front of a subject and along the line of march. This distance is called the head fixation distance. Head fixation distance provides the fundamental framework necessary for understanding the functional significance of the vestibular reflexes that couple head motion to eye motion. This framework facilitates the intelligent design of counter-measures for the effects of exposure to microgravity upon the vestibular ocular reflexes. Ideal trajectory analysis is a simple candidate countermeasure based upon quantifying body sway during repeated up and down stair stepping. It provides one number that estimates the body sway deviation from an ideal sinusoidal body sway trajectory normalized on the subject's height. This concept has been developed with NSBRI funding in less than one year. These findings are explained in more detail below. Compared to assessments of the vestibuo-ocular reflex, analysis of vestibular effects on locomotor function is relatively less well developed

  9. Assessing the Benefits of Global Climate Stabilization Within an Integrated Modeling Framework

    Science.gov (United States)

    Beach, R. H.

    2015-12-01

    Increasing atmospheric carbon dioxide levels, higher temperatures, altered precipitation patterns, and other climate change impacts have already begun to affect US agriculture and forestry, with impacts expected to become more substantial in the future. There have been a number of studies of climate change impacts on agriculture or forestry. However, relatively few studies explore climate change impacts on both agriculture and forests simultaneously, including the interactions between alternative land uses and implications for market outcomes. Additionally, there is a lack of detailed analyses of the effects of stabilization scenarios relative to unabated emissions scenarios. Such analyses are important for developing estimates of the benefits of those stabilization scenarios, which can play a vital role in assessing tradeoffs associated with allocating resources across alternative mitigation and adaptation activities. We provide an analysis of the potential benefits of global climate change mitigation for US agriculture and forestry through 2100, accounting for landowner decisions regarding land use, crop mix, and management practices. The analytic approach involves a combination of climate models, a crop process model (EPIC), a dynamic vegetation model used for forests (MC1), and an economic model of the US forestry and agricultural sector (FASOM-GHG). We find substantial impacts on productivity, commodity markets, and consumer and producer welfare for the stabilization scenario relative to unabated climate change, though the magnitude and direction of impacts vary across regions and commodities. Although there is variability in welfare impacts across climate simulations, we find positive net benefits from stabilization in all cases, with cumulative impacts ranging from 32.7 billion to 54.5 billion over the period 2015-2100. Our estimates contribute to the literature on potential benefits of GHG mitigation and can help inform policy decisions weighing alternative

  10. Quantitative modeling assesses the contribution of bond strengthening, rebinding and force sharing to the avidity of biomolecule interactions.

    Directory of Open Access Journals (Sweden)

    Valentina Lo Schiavo

    Full Text Available Cell adhesion is mediated by numerous membrane receptors. It is desirable to derive the outcome of a cell-surface encounter from the molecular properties of interacting receptors and ligands. However, conventional parameters such as affinity or kinetic constants are often insufficient to account for receptor efficiency. Avidity is a qualitative concept frequently used to describe biomolecule interactions: this includes incompletely defined properties such as the capacity to form multivalent attachments. The aim of this study is to produce a working description of monovalent attachments formed by a model system, then to measure and interpret the behavior of divalent attachments under force. We investigated attachments between antibody-coated microspheres and surfaces coated with sparse monomeric or dimeric ligands. When bonds were subjected to a pulling force, they exhibited both a force-dependent dissociation consistent with Bell's empirical formula and a force- and time-dependent strengthening well described by a single parameter. Divalent attachments were stronger and less dependent on forces than monovalent ones. The proportion of divalent attachments resisting a force of 30 piconewtons for at least 5 s was 3.7 fold higher than that of monovalent attachments. Quantitative modeling showed that this required rebinding, i.e. additional bond formation between surfaces linked by divalent receptors forming only one bond. Further, experimental data were compatible with but did not require stress sharing between bonds within divalent attachments. Thus many ligand-receptor interactions do not behave as single-step reactions in the millisecond to second timescale. Rather, they exhibit progressive stabilization. This explains the high efficiency of multimerized or clustered receptors even when bonds are only subjected to moderate forces. Our approach provides a quantitative way of relating binding avidity to measurable parameters including bond

  11. Quantitative Modeling Assesses the Contribution of Bond Strengthening, Rebinding and Force Sharing to the Avidity of Biomolecule Interactions

    Science.gov (United States)

    Lo Schiavo, Valentina; Robert, Philippe; Limozin, Laurent; Bongrand, Pierre

    2012-01-01

    Cell adhesion is mediated by numerous membrane receptors. It is desirable to derive the outcome of a cell-surface encounter from the molecular properties of interacting receptors and ligands. However, conventional parameters such as affinity or kinetic constants are often insufficient to account for receptor efficiency. Avidity is a qualitative concept frequently used to describe biomolecule interactions: this includes incompletely defined properties such as the capacity to form multivalent attachments. The aim of this study is to produce a working description of monovalent attachments formed by a model system, then to measure and interpret the behavior of divalent attachments under force. We investigated attachments between antibody-coated microspheres and surfaces coated with sparse monomeric or dimeric ligands. When bonds were subjected to a pulling force, they exhibited both a force-dependent dissociation consistent with Bell’s empirical formula and a force- and time-dependent strengthening well described by a single parameter. Divalent attachments were stronger and less dependent on forces than monovalent ones. The proportion of divalent attachments resisting a force of 30 piconewtons for at least 5 s was 3.7 fold higher than that of monovalent attachments. Quantitative modeling showed that this required rebinding, i.e. additional bond formation between surfaces linked by divalent receptors forming only one bond. Further, experimental data were compatible with but did not require stress sharing between bonds within divalent attachments. Thus many ligand-receptor interactions do not behave as single-step reactions in the millisecond to second timescale. Rather, they exhibit progressive stabilization. This explains the high efficiency of multimerized or clustered receptors even when bonds are only subjected to moderate forces. Our approach provides a quantitative way of relating binding avidity to measurable parameters including bond maturation, rebinding and

  12. Young adult patient with two palatally maxillary impacted canines and forced traction on rigid arches of stabilization. Case report.

    Science.gov (United States)

    Mucedero, M; Pezzuto, C; Rozzi, M; Ricchiuti, M R; Cozza, P

    2016-01-01

    Young adult patient treated for impaction of two maxillary canines. C.S., 15 years, female. Diagnostic evaluation by clinical and radiographic examinations shows permanent dentition with persistence of 5.3 and 6.3, impaction of 1.3 and 2.3, dento-skeletal Cl I malocclusion, normodivergence of bone bases. Analysis of TC dentalscan confirms the palatal impaction of 1.3 and 2.3. The treatment plan provided an orthodontic-surgical approach for adequate space management in dental arch, evaluation of eruption movements, choice of anchorage device, surgical exposure and application of the brackets. Deciduous canines have been extracted and an edgewise appliance with rigid rectangular full thickness archwires has been used to align the arches and to obtain maximum anchorage during the forced traction. The surgical phase, for exposure of 1.3 and 2.3 respectively, performed an open technique by excisional uncovering and a close technique by a repositioned flap. The case has been finalized for the achievement of the right occlusal keys. The possibility to choose the surgical technique depending on the intraosseous position of impacted teeth in association to the edgewise therapy with full thickness arches allows to realize an effectiveness surgical-orthodontic approach for the forced traction of impacted teeth in a favourable position.

  13. An ergonomic modular foot platform for isometric force/torque measurements in poststroke functional assessment: A pilot study

    OpenAIRE

    Stefano Mazzoleni, PhD; Jo Van Vaerenbergh, PhD; Emma Stokes, PhD; Gábor Fazekas, MD, PhD; Paolo Dario, PhD; Eugenio Guglielmelli, PhD

    2012-01-01

    The main goal of this article is to present the design, technical development, and preliminary validation of an innovative mechatronic device for force/torque measurements taken from the human foot using pilot data. The device, formed by a mobile platform equipped with two six-axis force/torque sensors, was used to perform accurate quantitative measurements during isometric exercises, aimed at performing functional assessment tests in poststroke patients undergoing a rehabilitation treatment....

  14. VALIDATING A COMPUTER-BASED TECHNIQUE FOR ASSESSING STABILITY TO FAILURE STRESS

    Directory of Open Access Journals (Sweden)

    I. F. Arshava

    2013-03-01

    Full Text Available An upsurge of interest in the implicit personality assessment, currently observed both in personality psycho-diagnostics and in experimental studies of social attitudes and prejudices, signals the shifting of researchers’ attention from de?ning between-person personality taxonomy to specifying comprehensive within-person processes, the dynamics of which can be captured at the level of an individual case. This research examines the possibility of the implicit assessment of the individual’s stability vs. susceptibility to failure stress by comparing the degrees of ef?cacy in the voluntary self-regulation of a computer-simulated information-processing activity under different conditions (patent of Ukraine № 91842, issued in 2010. By exposing two groups of participants (university undergraduates to processing the information, the scope of which exceeds the human short-term memory capacity at one of the stages of the modeled activity an unexpected and unavoidable failure is elicited. The participants who retain stability of their self-regulation behavior after having been exposed to failure, i.e. who keep processing information as effectively as they did prior to failure, are claimed to retain homeostasis and thus possess emotional stability. Those, who loose homeostasis after failure and display lower standards of self-regulation behavior, are considered to be susceptible to stress. The validity of the suggested type of the implicit diagnostics was empirically tested by clustering (K-means algorithm two samples of the participants on the  properties of their self-regulation behavior and testing between-cluster differences by a set of the explicitly assessed variables: Action control ef?cacy (Kuhl, 2001, preferred strategies of Coping with Stressful Situations (Endler, Parker, 1990,  Purpose-in-Life orientation (a Russian version of the test by Crumbaugh and Maholick, modi?ed by D.Leontiev, 1992, Psychological Well-being (Ryff, 1989

  15. Assessment of Physical Stability and Antioxidant Activity of Polysiloxane Polyalkyl Polyether Copolymer-Based Creams

    Directory of Open Access Journals (Sweden)

    Atif Ali

    2013-01-01

    Full Text Available The purpose of the present work was to investigate the changes on physical stability (color, creaming, liquefaction, pH, conductivity, centrifugation, viscosity and rheological parameters by non-ionic surfactant polysiloxane polyalkyl polyether copolymer based creams following inclusion of plant extract containing phenolic compounds. The antioxidant activity of the plant extract alone and after addition in the cream was assessed using the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH assay. Physical stability was assessed by submitting the creams to storage at 8°C, 25°C, 40°C, and at 40°C with 70% RH (relative humidity for a period of two months. Physical characteristics of polysiloxane polyalkyl polyether copolymer based creams, that is, color, creaming, liquefaction, centrifugation and pH were noted at various intervals for 2 months. The viscosities and rheological behavior of creams were determined using a rotational rheometer. Data were analyzed by using Brookfield Software Rheocalc version (2.6 with IPC Paste and Power Law (PL math models. Cream with plant extract showed pseudo plastic behaviour with decreasing on viscosity. The Acacia nilotica (AN extract alone and the cream containing this extract showed great antioxidant and free radical scavenging activities. Power Law and IPC analysis were found to fit all the rheograms.

  16. Assessment of dental implant stability by means of the electromechanical impedance method

    International Nuclear Information System (INIS)

    Boemio, Giovanni; Rizzo, Piervincenzo; Nardo, Luigi De

    2011-01-01

    Implant stability is a prerequisite for functional recovery in load-bearing prostheses. Robust, reliable and noninvasive methods to assess the bone interface of dental and orthopedic implants are increasingly demanded for clinical diagnosis and direct prognosis. In this paper, a study of the feasibility of a noninvasive method based on electromechanical impedance (EMI) to assess dental prostheses stability is presented. Two different dental screws were entrenched in polyurethane foams (Sawbones ® ) and immersed in a solution of nitric acid to allow material degradation, inversely simulating a bone healing process. This process was monitored by bonding a piezoceramic transducer (PZT) to the implant and measuring the admittance of the PZT over time. It was found that the PZT's conductance and the statistical features associated with its analysis were sensitive to the degradation of the foams and can be correlated to the Sawbones mechanical properties. The present study shows promising results and may pave the road towards an innovative approach for the noninvasive monitoring of implanted prostheses

  17. A reliable unipedal stance test for the assessment of balance using a force platform.

    Science.gov (United States)

    Ponce-González, J G; Sanchis-Moysi, J; González-Henriquez, J J; Arteaga-Ortiz, R; Calbet, J A L; Dorado, C

    2014-02-01

    The aim was to develop a unipedal stance test for the assessment of balance using a force platform. A single-leg balance test was conducted in 23 students (mean ± SD) age: 23 ± 3 years) in a standard position limiting the movement of the arms and non-supporting leg. Six attempts, with both the jumping (JL) and the contralateral leg (CL), were performed under 3 conditions: 1) eyes opened; 2) eyes closed; 3) eyes opened and executing a precision task. The same protocol was repeated two-week apart. The mean and the best result of the six attempts performed each day were taken as representative of balance. The speed of the centre of pressure (CP-Speed) showed excellent reliability for the "best result" analysis in all tests (ICCs 0.87-0.97), except in the test with the eyes closed performed on the CL (ICCtest. The single-leg stance balance test proposed is a reliable method to assess balance, especially when performed in a static position, with the eyes opened and using the best result of six attempts as reference, independently of the stance leg.

  18. Estimation of mountain slope stability depending on ground consistency and slip-slide resistance changes on impact of dynamic forces

    Science.gov (United States)

    Hayroyan, H. S.; Hayroyan, S. H.; Karapetyan, K. A.

    2018-04-01

    In this paper, three types of clayish soils with different consistency and humidity properties and slip-slide resistance indexes are considered on impact of different cyclic shear stresses. The side-surface deformation charts are constructed on the basis of experimental data obtained testing cylindrical soil samples. It is shown that the fluctuation amplitude depends on time and the consistency index depends on the humidity condition in the soil inner contact and the connectivity coefficients. Consequently, each experiment is interpreted. The main result of this research is that it is necessary to make corrections in the currently active schemes of slip-hazardous slopes stability estimation, which is a crucial problem requiring ASAP solution.

  19. ESI-MSn and LC-ESI-MS studies to characterize forced degradation products of bosentan and a validated stability-indicating LC-UV method.

    Science.gov (United States)

    Bansal, Gulshan; Singh, Ranjit; Saini, Balraj; Bansal, Yogita

    2013-01-01

    The present study reports the characterization of forced degradation products of bosentan and a validated stability-indicating HPLC method for the stability testing of bosentan tablets. The forced degradation was carried out under the conditions of hydrolysis, oxidation, dry heat and photolysis. The drug was found unstable in acid, alkali and oxidative media whereas stable to the hydrolysis in water, to dry heat and to photolysis. In total, six degradation products were formed in all conditions which were resolved in a single run on a C-18 column with gradient elution using ammonium acetate buffer (pH 4.5, 5.0mM), methanol and acetonitrile. Structures of all the degradation products were characterized through +ESI-MS(n) and LC-ESI-MS spectral data of bosentan as well as LC-ESI-MS spectral data of the products. The products II-VI were characterized as 6-amino-[2,2']bipyrimidinyl-4,5-diol, 6-amino-5-(2-methoxyphenoxy)-[2,2']-bipyrimidinyl-4-ol, 2-[6-amino-5-(2-methoxyphenoxy)-[2,2']-bipyrimidinyl-4-yloxy]-ethanol, 4-tert-butyl-N-[6-(1-methoxyethoxy)-5-(2-methoxyphenoxy)-[2,2']-bipyrimidinyl-4-yl]-benzenesulfonamide and 4-tert-butyl-N-[6-hydroxy-5-(2-methoxyphenoxy)-[2,2']bipyrimidinyl-4-yl]-benzenesulfonamide, respectively. The peak of the product I was found to be due to two secondary degradation products which co-eluted and were characterized as β-hydroxyethyl p-tert-butylphenylsulfonate (Ia) and 2-[2-(2-hydroxyethoxy)-phenoxy]-ethanol (Ib). These products were formed due to hydrolysis of sulfonamide and alkylaryl ether and the diaryl ether linkages as well as dehydration of the primary alcohol group. The most probable degradation mechanisms were proposed. The HPLC method was found to be stability-indicating, linear (2-100 μg ml(-1)), accurate, precise, sensitive, specific, rugged and robust for quantitation of the drug. The method was applied to the stability testing of the commercially available bosentan tablets successfully. Copyright © 2012 Elsevier B.V. All

  20. 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

  1. Application of a high-throughput relative chemical stability assay to screen therapeutic protein formulations by assessment of conformational stability and correlation to aggregation propensity.

    Science.gov (United States)

    Rizzo, Joseph M; Shi, Shuai; Li, Yunsong; Semple, Andrew; Esposito, Jessica J; Yu, Shenjiang; Richardson, Daisy; Antochshuk, Valentyn; Shameem, Mohammed

    2015-05-01

    In this study, an automated high-throughput relative chemical stability (RCS) assay was developed in which various therapeutic proteins were assessed to determine stability based on the resistance to denaturation post introduction to a chaotrope titration. Detection mechanisms of both intrinsic fluorescence and near UV circular dichroism (near-UV CD) are demonstrated. Assay robustness was investigated by comparing multiple independent assays and achieving r(2) values >0.95 for curve overlays. The complete reversibility of the assay was demonstrated by intrinsic fluorescence, near-UV CD, and biologic potency. To highlight the method utility, we compared the RCS assay with differential scanning calorimetry and dynamic scanning fluorimetry methodologies. Utilizing C1/2 values obtained from the RCS assay, formulation rank-ordering of 12 different mAb formulations was performed. The prediction of long-term stability on protein aggregation is obtained by demonstrating a good correlation with an r(2) of 0.83 between RCS and empirical aggregation propensity data. RCS promises to be an extremely useful tool to aid in candidate formulation development efforts based on the complete reversibility of the method to allow for multiple assessments without protein loss and the strong correlation between the C1/2 data obtained and accelerated stability under stressed conditions. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  2. Assessing water resources in Azerbaijan using a local distributed model forced and constrained with global data

    Science.gov (United States)

    Bouaziz, Laurène; Hegnauer, Mark; Schellekens, Jaap; Sperna Weiland, Frederiek; ten Velden, Corine

    2017-04-01

    with NOAA stations and that MSWEP slightly overestimated precipitation amounts. On a daily basis, there were discrepancies in the peak timing and magnitude between measured precipitation and the global products. A bias between EU-WATCH and WFDEI temperature and potential evaporation was observed and to model the water balance correctly, it was needed to correct EU-WATCH to WFDEI mean monthly values. Overall, the available sources enabled rapid set-up of a hydrological model including the forcing of the model with a relatively good performance to assess water resources in Azerbaijan with a limited calibration effort and allow for a similar set-up anywhere in the world. Timing and quantification of peak volume remains a weakness in global data, making it difficult to be used for some applications (flooding) and for detailed calibration. Selecting and comparing different sources of global meteorological data is important to have a reliable set which improves model performance. - Beck et al., 2016. MSWEP: 3-hourly 0.25° global gridded precipitation (1979-2014) by merging gauge, satellite, and reanalysis data. Hydrol. Earth Syst. Sci. Discuss. - Dai Y. et al. ,2013. Development of a China Dataset of Soil Hydraulic Parameters Using Pedotransfer Functions for Land Surface Modeling. Journal of Hydrometeorology - Harding, R. et al., 2011., WATCH: Current knowledge of the Terrestrial global water cycle, J. Hydrometeorol. - Schellekens, J. et al., 2014. Rapid setup of hydrological and hydraulic models using OpenStreetMap and the SRTM derived digital elevation model. Environmental Modelling&Software - Wang-Erlandsson L. et al., 2016. Global Root Zone Storage Capacity from Satellite-Based Evaporation. Hydrology and Earth System Sciences - Weedon, G. et al., 2014. The WFDEI meteorological forcing data set: WATCH Forcing Data methodology applied to ERA-Interim reanalysis data, Water Resources Research.

  3. Assessing the accuracy and stability of variable selection methods for random forest modeling in ecology.

    Science.gov (United States)

    Fox, Eric W; Hill, Ryan A; Leibowitz, Scott G; Olsen, Anthony R; Thornbrugh, Darren J; Weber, Marc H

    2017-07-01

    Random forest (RF) modeling has emerged as an important statistical learning method in ecology due to its exceptional predictive performance. However, for large and complex ecological data sets, there is limited guidance on variable selection methods for RF modeling. Typically, either a preselected set of predictor variables are used or stepwise procedures are employed which iteratively remove variables according to their importance measures. This paper investigates the application of variable selection methods to RF models for predicting probable biological stream condition. Our motivating data set consists of the good/poor condition of n = 1365 stream survey sites from the 2008/2009 National Rivers and Stream Assessment, and a large set (p = 212) of landscape features from the StreamCat data set as potential predictors. We compare two types of RF models: a full variable set model with all 212 predictors and a reduced variable set model selected using a backward elimination approach. We assess model accuracy using RF's internal out-of-bag estimate, and a cross-validation procedure with validation folds external to the variable selection process. We also assess the stability of the spatial predictions generated by the RF models to changes in the number of predictors and argue that model selection needs to consider both accuracy and stability. The results suggest that RF modeling is robust to the inclusion of many variables of moderate to low importance. We found no substantial improvement in cross-validated accuracy as a result of variable reduction. Moreover, the backward elimination procedure tended to select too few variables and exhibited numerous issues such as upwardly biased out-of-bag accuracy estimates and instabilities in the spatial predictions. We use simulations to further support and generalize results from the analysis of real data. A main purpose of this work is to elucidate issues of model selection bias and instability to ecologists interested in

  4. Fiber Fabry-Perot Force Sensor with Small Volume and High Performance for Assessing Fretting Damage of Steam Generator Tubes.

    Science.gov (United States)

    Huang, Peijian; Wang, Ning; Li, Junying; Zhu, Yong; Zhang, Jie

    2017-12-13

    Measuring the radial collision force between the steam generator tube (SGT) and the tube support plate (TSP) is essential to assess the fretting damage of the SGT. In order to measure the radial collision force, a novel miniaturized force sensor based on fiber Fabry-Perot (F-P) was designed, and the principle and characteristics of the sensor were analyzed in detail. Then, the F-P force sensor was successfully fabricated and calibrated, and the overall dimensions of the encapsulated fiber F-P sensor were 17 mm × 5 mm × 3 mm (L × W × H). The sensor works well in humid, high pressure (10 MPa), high temperature (350 °C), and vibration (40 kHz) environments. Finally, the F-P force sensors were installed in a 1:1 steam generator test loop, and the radial collision force signals between the SGT and the TSP were obtained. The experiments indicated that the F-P sensor with small volume and high performance could help in assessing the fretting damage of the steam generator tubes.

  5. Stabilizing and retaining a quality nursing work force through the use of the Married State Preceptorship Model.

    Science.gov (United States)

    Figueroa, Solimar; Bulos, Marlene; Forges, Edwina; Judkins-Cohn, Tanya

    2013-08-01

    The nursing shortage requires new graduate registered nurses (RNs) to work at the bedside, often leading to a shortened orientation period and increased stress. In the Married State Preceptorship Model (MSPM), the preceptor and the preceptee work together as the new graduate RN transitions to the bedside while maintaining safety and quality. This study explored first-year turnover rates of new graduate RNs and new graduate RNs' and preceptors' perceptions of the MSPM in transitioning new graduate RNs to practice. Focus groups and surveys were used with 108 new graduate RNs and 100 preceptors. Four themes emerged for new graduate RNs: partnership, critical thinking, learning, and transition. A statistically significant decrease in turnover rates was seen with MSPM versus traditional precepting. Survey data found that new graduate RNs and preceptors perceived the MSPM as promoting safety and reducing anxiety. The MSPM allows organizations to retain a quality nursing work force focused on safety patient care by transitioning new graduate RNs into the practice setting. Copyright 2013, SLACK Incorporated.

  6. Theoretical assessment of the disparity in the electrostatic forces between two point charges and two conductive spheres of equal radii

    Science.gov (United States)

    Kolikov, Kiril

    2016-11-01

    The Coulomb's formula for the force FC of electrostatic interaction between two point charges is well known. In reality, however, interactions occur not between point charges, but between charged bodies of certain geometric form, size and physical structure. This leads to deviation of the estimated force FC from the real force F of electrostatic interaction, thus imposing the task to evaluate the disparity. In the present paper the problem is being solved theoretically for two charged conductive spheres of equal radii and arbitrary electric charges. Assessment of the deviation is given as a function of the ratio of the distance R between the spheres centers to the sum of their radii. For the purpose, relations between FC and F derived in a preceding work of ours, are employed to generalize the Coulomb's interactions. At relatively short distances between the spheres, the Coulomb force FC, as estimated to be induced by charges situated at the centers of the spheres, differ significantly from the real force F of interaction between the spheres. In the case of zero and non-zero charge we prove that with increasing the distance between the two spheres, the force F decrease rapidly, virtually to zero values, i.e. it appears to be short-acting force.

  7. Channel Planform Dynamics Monitoring and Channel Stability Assessment in Two Sediment-Rich Rivers in Taiwan

    Directory of Open Access Journals (Sweden)

    Cheng-Wei Kuo

    2017-01-01

    Full Text Available Recurrent flood events induced by typhoons are powerful agents to modify channel morphology in Taiwan’s rivers. Frequent channel migrations reflect highly sensitive valley floors and increase the risk to infrastructure and residents along rivers. Therefore, monitoring channel planforms is essential for analyzing channel stability as well as improving river management. This study analyzed annual channel changes along two sediment-rich rivers, the Zhuoshui River and the Gaoping River, from 2008 to 2015 based on satellite images of FORMOSAT-2. Channel areas were digitized from mid-catchment to river mouth (~90 km. Channel stability for reaches was assessed through analyzing the changes of river indices including braid index, active channel width, and channel activity. In general, the valley width plays a key role in braided degree, active channel width, and channel activity. These indices increase as the valley width expands whereas the braid index decreases slightly close to the river mouth due to the change of river types. This downstream pattern in the Zhuoshui River was interrupted by hydraulic construction which resulted in limited changes downstream from the weir, due to the lack of water and sediment supply. A 200-year flood, Typhoon Morakot in 2009, induced significant changes in the two rivers. The highly active landscape in Taiwan results in very sensitive channels compared to other regions. An integrated Sensitivity Index was proposed for identifying unstable reaches, which could be a useful reference for river authorities when making priorities in river regulation strategy. This study shows that satellite image monitoring coupled with river indices analysis could be an effective tool to evaluate spatial and temporal changes in channel stability in highly dynamic river systems.

  8. Stability assessment of a multi-port power electronic interface for hybrid micro-grid applications

    Science.gov (United States)

    Shamsi, Pourya

    Migration to an industrial society increases the demand for electrical energy. Meanwhile, social causes for preserving the environment and reducing pollutions seek cleaner forms of energy sources. Therefore, there has been a growth in distributed generation from renewable sources in the past decade. Existing regulations and power system coordination does not allow for massive integration of distributed generation throughout the grid. Moreover, the current infrastructures are not designed for interfacing distributed and deregulated generation. In order to remedy this problem, a hybrid micro-grid based on nano-grids is introduced. This system consists of a reliable micro-grid structure that provides a smooth transition from the current distribution networks to smart micro-grid systems. Multi-port power electronic interfaces are introduced to manage the local generation, storage, and consumption. Afterwards, a model for this micro-grid is derived. Using this model, the stability of the system under a variety of source and load induced disturbances is studied. Moreover, pole-zero study of the micro-grid is performed under various loading conditions. An experimental setup of this micro-grid is developed, and the validity of the model in emulating the dynamic behavior of the system is verified. This study provides a theory for a novel hybrid micro-grid as well as models for stability assessment of the proposed micro-grid.

  9. MR tomography in the assessment of functional stability of posterolateral lumbar fusions

    International Nuclear Information System (INIS)

    Lang, P.; Genant, H.K.; Chafetz, N.; Steiger, P.; Stoller, D.; California Univ., San Francisco

    1987-01-01

    MR tomography was used to assess functional lumbar stability in 30 patients with posterolateral fusions. The vertebral bodies of 9 of the 12 patients with unstable lumbar fusions presented with areas of decreased signal intensity on T 1 - and intermediately weighted images, which increased on T 2 -weighting. The vertebrae of 15 of the 18 patients with stable fusions demonstrated zones of increased signal intensity on T 1 - and intermediately weighted images, which were less intense or invisible on T 2 -weighting. Surgical correlation was available in 11 of the 30 patients studied. Hyperemia and inflammation appear to be responsible for the abnormal signal intensities in the patients with stable fusions, whereas an increase in adipose marrow due to decreased biomechanical stress is thought to account for the atypical signal intensities in the vertebral bodies of the patients with stable fusions. MR tomography seems to be a potential method for evaluating functional lumbar fusion stability. MR tomography may be particularly helpful in those patients with multiple back surgeries and possible instability, recurrent disc herniation, or post-operative fibrosis. MR is recommended in the patient, who appears clinically unstable, whose radiographs and CT, however, do not demonstrate fusion failure. (orig.) [de

  10. CHANGE IN CONDYLAR POSITION AND SKELETAL STABILITY ASSESSMENT FOLLOWING BSSO FOR MANDIBULAR SET BACK

    Directory of Open Access Journals (Sweden)

    Manjunath

    2015-09-01

    Full Text Available Change in condylar position following mandibular bilateral sagittal split osteotomy (BSSO has been implicated as an important factor in the appearance of immediate postoperative relapse during rigid fixation. It has been suggested that the control of the condylar segment following BSSO is the most important aspect in preventing relapse. The study was done to evaluate changes in position of condyle taken with lateral and frontal cephalograms with 20 patients were assessed, 10 male and 10 female patients wer e divided as group 1 and group 2. Patients undergoing sagittal split ramus osteotomy for mandibular set back were selected; radiographs before operation/surgery, immediately after surgery, 3 months and 6 months post - surgery. Differences between groups were measured by PAIRED ‘T’ TEST a nd time dependent changes in cephalometric measurements were examined by FISCHERS TEST. The present study results conclude significant difference occurring in both proximal and distal segment including condyle. Occlusal stabil ity and skeletal stability also maintained post operatively

  11. Turbofan forced mixer lobe flow modeling. 1: Experimental and analytical assessment

    Science.gov (United States)

    Barber, T.; Paterson, R. W.; Skebe, S. A.

    1988-01-01

    A joint analytical and experimental investigation of three-dimensional flowfield development within the lobe region of turbofan forced mixer nozzles is described. The objective was to develop a method for predicting the lobe exit flowfield. In the analytical approach, a linearized inviscid aerodynamical theory was used for representing the axial and secondary flows within the three-dimensional convoluted mixer lobes and three-dimensional boundary layer analysis was applied thereafter to account for viscous effects. The experimental phase of the program employed three planar mixer lobe models having different waveform shapes and lobe heights for which detailed measurements were made of the three-dimensional velocity field and total pressure field at the lobe exit plane. Velocity data was obtained using Laser Doppler Velocimetry (LDV) and total pressure probing and hot wire anemometry were employed to define exit plane total pressure and boundary layer development. Comparison of data and analysis was performed to assess analytical model prediction accuracy. As a result of this study a planar mixed geometry analysis was developed. A principal conclusion is that the global mixer lobe flowfield is inviscid and can be predicted from an inviscid analysis and Kutta condition.

  12. Transient Dynamics of Electric Power Systems: Direct Stability Assessment and Chaotic Motions

    Science.gov (United States)

    Chu, Chia-Chi

    A power system is continuously experiencing disturbances. Analyzing, predicting, and controlling transient dynamics, which describe transient behaviors of the power system following disturbances, is a major concern in the planning and operation of a power utility. Important conclusions and decisions are made based on the result of system transient behaviors. As today's power network becomes highly interconnected and much more complex, it has become essential to enhance the fundamental understanding of transient dynamics, and to develop fast and reliable computational algorithms. In this thesis, we emphasize mathematical rigor rather than physical insight. Nonlinear dynamical system theory is applied to study two fundamental topics: direct stability assessment and chaotic motions. Conventionally, power system stability is determined by calculating the time-domain transient behaviors for a given disturbance. In contrast, direct methods identify whether or not the system will remain stable once the disturbance is removed by comparing the corresponding energy value of the post-fault system to a calculated threshold value. Direct methods not only avoid the time-consuming numerical integration of the time domain approach, but also provide a quantitative measure of the degree of system stability. We present a general framework for the theoretical foundations of direct methods. Canonical representations of network-reduction models as well as network-preserving models are proposed to facilitate the analysis and the construction of energy functions of various power system models. An advanced and practical method, called the boundary of stability region based controlling unstable equilibrium point method (BCU method), of computing the controlling unstable equilibrium point is proposed along with its theoretical foundation. Numerical solution algorithms capable of supporting on-line applications of direct methods are provided. Further possible improvements and enhancements are

  13. Impedance Stability Assessment of Active Damping Strategies for LCL Grid-Connected Converters

    DEFF Research Database (Denmark)

    Diaz, Enrique Rodriguez; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2017-01-01

    as a countermeasure. This paper analyses the robustness of the closed-loop dynamics when different active damping strategies are implemented. Due to their readiness and simplicity, the following schemes are considered: 1) filtered capacitor voltage feed-forward and 2) notch filters in cascade with the main current......The use of LCL filters is a well accepted solution to attenuate the harmonics created by the pulsewidth modulation (PWM). However, inherently LCL filters have a resonance region where the unwanted harmonics are amplified, which can compromise instability. Active damping strategies are implemented...... controller. The impedance/admittance stability formulation is used to model the system, which has been proven to be very convenient for the assessment of robustness. The design case study shows that the filtered capacitor voltage feed-forward provides a more robust implementation than the one based...

  14. Isolation and Assessment of Stability of Six Formulations of Entomopathogenic Beauveria bassiana.

    Science.gov (United States)

    Mwamburi, Lizzy A

    2016-01-01

    Beauveria bassiana is the most widely studied and exploited entomopathogen. The development of a suitable formulation for B. bassiana is a critical component in aiding the entomopathogen germinate and infect the host. In addition to being economical to produce, having high residual activity, it is also important that the formulation is easy to handle, stable during storage, and convenient to mix and apply and be consistently effective in controlling the target pest.In this chapter we describe preparation of experimental formulations of conidia of B. bassiana. The formulations are prepared with barley, rice, wheat bran, clay, kaolin, and peat. The protocol for assessing the stability of the formulations of B. bassiana is also described.

  15. STUDY REGARDING THE ASSESSMENT OF THE FINANCIAL STABILITY OF THE ECONOMIC ENTITIES

    Directory of Open Access Journals (Sweden)

    N. Baltes

    2016-11-01

    Full Text Available The research presents both theoretical and practicalthe evolution of the financial stability assessed through the solvency indicators, the real economic growth rate and the GDP deflator in the manufacturing companies from Romania, through the Vector Autoregression Model (VAR. The sample consists in 36 companies belonging to the manufacturing industry in Romania, listed on the Bucharest Stock Exchange, on the first and second category. The study is conducted during the period 2007-2014 and demonstrated the fact that a change in the real economic growth causes a positive change in the GDP deflator. Not lastly, the change of the real economic growth also determines a positive change of the patrimonial solvency, and a change in the GDP deflator produces a reduction of the patrimonial solvency.

  16. Phasor Measurement Unit Test and Applications for Small Signal Stability Assessment and Improvement of Power System

    DEFF Research Database (Denmark)

    Ghiga, Radu

    to be less predictable. Therefore, the methods used for stability and security assessment will most likely use information from the wide-area measurements systems (WAMS). The work presented in this thesis deals on one hand with the development of test methods and validation of phasor measurement units (PMUs......) which are considered to be one of the key technologies in WAMS, and on the other hand with the possibility of using PMU measurements together with large wind power plants (WPPs) to help improve the damping of inter area oscillations. To validate the PMUs, a laboratory test setup is assembled....... The hardware components are capable of generating, with the required accuracy, the test signals injected in the PMUs. The signals are created according to the requirements defined in the current IEEE C37.118.1-2011 standard, to test the steady-state and dynamic compliance of the PMUs. The performance...

  17. Assessment of chromatographic methods for the chemical stability of a new miconazole nitrate cream

    International Nuclear Information System (INIS)

    Garcia Pulpeiro, Oscar; Calzadilla Aguiar, Wendy; Rodriguez Bencomo, Wendy

    2013-01-01

    To assess the chromatographic methods for the chemical stability of a new 2 % miconazol nitrate cream. arious degradation conditions were firstly used in the raw material miconazole nitrate in order to obtain the possible degradation products of this drug and to evaluate them by thin layer chromatography-based method, which was validated to identify the degradation products in the new cream. The performance of the official method based on high resolution liquid chromatography and reported in British Pharmacopoeia 2010 was evaluated, and its selectivity against the possible degradation products were also analyzed. Both chromatographic methods were applied to the analysis of cream samples from the three pilot batches under heat stress for 30 days

  18. Siting of a low-level radioactive waste management facility - environmental assessment experiences of the Canadian siting task force

    International Nuclear Information System (INIS)

    Gorber, D.M.; Story, V.A.

    1995-01-01

    After public opposition to the plans for a low-level radioactive waste facility at one of two candidate areas at Port Hope, Canada the Environmental Assessment process was postponed, and an independent Siting Process Task Force was set-up to assess the most suitable technologies for LLRW disposal, the areas with the best potential in the province to use these technologies, and the most promising approaches to site selection. The Task Force recommended a five-phased siting process known as the 'Co-operative Siting Process', which was based on the voluntary participation of local communities and a collaborative, joint-planning style of decision making. An independent Siting Task Force was to be established to ensure that the principles of the recommended process was upheld. This siting process is still underway, and problems and successes that have been encountered are summarized in this contribution

  19. Genomic stability and physiological assessments of live offspring sired by a bull clone, Starbuck II.

    Science.gov (United States)

    Ortegon, H; Betts, D H; Lin, L; Coppola, G; Perrault, S D; Blondin, P; King, W A

    2007-01-01

    It appears that overt phenotypic abnormalities observed in some domestic animal clones are not transmitted to their progeny. The current study monitored Holstein heifers sired by a bull clone, Starbuck II, from weaning to puberty. Genomic stability was assessed by telomere length status and chromosomal analysis. Growth parameters, blood profiles, physical exams and reproductive parameters were assessed for 12 months (and compared to age-matched control heifers). Progeny sired by the clone bull did not differ (P>0.05) in weight, length and height compared to controls. However, progeny had lower heart rates (HR) (P=0.009), respiratory rates (RR) (P=0.007) and body temperature (P=0.03). Hematological profiles were within normal ranges and did not differ (P>0.05) between both groups. External and internal genitalia were normal and both groups reached puberty at expected ages. Progeny had two or three ovarian follicular waves per estrous cycle and serum progesterone concentrations were similar (P=0.99) to controls. Telomere lengths of sperm and blood cells from Starbuck II were not different (P>0.05) than those of non-cloned cattle; telomere lengths of progeny were not different (P>0.05) from age-matched controls. In addition, progeny had normal karyotypes in peripheral blood leukocytes compared to controls (89.1% versus 86.3% diploid, respectively). In summary, heifers sired by a bull clone had normal chromosomal stability, growth, physical, hematological and reproductive parameters, compared to normal heifers. Furthermore, they had moderate stress responses to routine handling and restraint.

  20. Objective Assessment of Laparoscopic Force and Psychomotor Skills in a Novel Virtual Reality-Based Haptic Simulator.

    Science.gov (United States)

    Prasad, M S Raghu; Manivannan, Muniyandi; Manoharan, Govindan; Chandramohan, S M

    2016-01-01

    Most of the commercially available virtual reality-based laparoscopic simulators do not effectively evaluate combined psychomotor and force-based laparoscopic skills. Consequently, the lack of training on these critical skills leads to intraoperative errors. To assess the effectiveness of the novel virtual reality-based simulator, this study analyzed the combined psychomotor (i.e., motion or movement) and force skills of residents and expert surgeons. The study also examined the effectiveness of real-time visual force feedback and tool motion during training. Bimanual fundamental (i.e., probing, pulling, sweeping, grasping, and twisting) and complex tasks (i.e., tissue dissection) were evaluated. In both tasks, visual feedback on applied force and tool motion were provided. The skills of the participants while performing the early tasks were assessed with and without visual feedback. Participants performed 5 repetitions of fundamental and complex tasks. Reaction force and instrument acceleration were used as metrics. Surgical Gastroenterology, Government Stanley Medical College and Hospital; Institute of Surgical Gastroenterology, Madras Medical College and Rajiv Gandhi Government General Hospital. Residents (N = 25; postgraduates and surgeons with 4 and ≤10 years of laparoscopic surgery). Residents applied large forces compared with expert surgeons and performed abrupt tool movements (p < 0.001). However, visual + haptic feedback improved the performance of residents (p < 0.001). In complex tasks, visual + haptic feedback did not influence the applied force of expert surgeons, but influenced their tool motion (p < 0.001). Furthermore, in complex tissue sweeping task, expert surgeons applied more force, but were within the tissue damage limits. In both groups, exertion of large forces and abrupt tool motion were observed during grasping, probing or pulling, and tissue sweeping maneuvers (p < 0.001). Modern day curriculum-based training should evaluate the skills

  1. Validity and reproducibility of crutch force and heart rate measurements to assess energy expenditure of paraplegic gait

    NARCIS (Netherlands)

    IJzerman, Maarten Joost; Baardman, Gert; van 't Hof, Martin A.; Boom, H.B.K.; Hermens, Hermanus J.; Veltink, Petrus H.

    1999-01-01

    Objective: To determine the validity and reproducibility of heart rate (HR) and crutch force measurements to estimate energy expenditure during paraplegic walking. Usefulness of these outcome measures in comparative trials was assessed in terms of responsiveness. Design: Cross-sectional validity was

  2. Physiological and methodological aspects of rate of force development assessment in human skeletal muscle

    DEFF Research Database (Denmark)

    Rodríguez-Rosell, David; Pareja-Blanco, Fernando; Aagaard, Per

    2018-01-01

    Rate of force development (RFD) refers to the ability of the neuromuscular system to increase contractile force from a low or resting level when muscle activation is performed as quickly as possible, and it is considered an important muscle strength parameter, especially for athletes in sports re......, which may aid to clarify the thinking of coaches and sports scientists in this area....

  3. Gulf Coast Ecosystem Restoration Task Force---Gulf of Mexico Ecosystem Science Assessment and Needs

    Science.gov (United States)

    Walker, Shelby; Dausman, Alyssa M.; Lavoie, Dawn L.

    2012-01-01

    The Gulf Coast Ecosystem Restoration Task Force (GCERTF) was established by Executive Order 13554 as a result of recommendations from “America’s Gulf Coast: A Long-term Recovery Plan after the Deepwater Horizon Oil Spill” by Secretary of the Navy Ray Mabus (Mabus Report). The GCERTF consists of members from 11 Federal agencies and representatives from each State bordering the Gulf of Mexico. The GCERTF was charged to develop a holistic, long-term, science-based Regional Ecosystem Restoration Strategy for the Gulf of Mexico. Federal and State agencies staffed the GCERTF with experts in fields such as policy, budgeting, and science to help develop the Strategy. The Strategy was built on existing authorities and resources and represents enhanced collaboration and a recognition of the shared responsibility among Federal and State governments to restore the Gulf Coast ecosystem. In this time of severe fiscal constraints, Task Force member agencies and States are committed to establishing shared priorities and working together to achieve them.As part of this effort, three staffers, one National Oceanic and Atmospheric Administration (NOAA) scientist and two U.S. Geological Survey (USGS) scientists, created and led a Science Coordination Team (SCT) to guide scientific input into the development of the Gulf of Mexico Regional Ecosystem Restoration Strategy. The SCT leads from the GCERTF coordinated more than 70 scientists from the Federal and State Task Force member agencies to participate in development of a restoration-oriented science document focused on the entire Gulf of Mexico, from inland watersheds to the deep blue waters. The SCT leads and scientists were organized into six different working groups based on expanded goals from the Mabus Report: Coastal habitats are healthy and resilient.Living coastal and marine resources are healthy, diverse, and sustainable.Coastal communities are adaptive and resilient.Storm buffers are sustainable.Inland habitats and

  4. Hydrological assessment of atmospheric forcing uncertainty in the Euro-Mediterranean area using a land surface model

    Science.gov (United States)

    Gelati, Emiliano; Decharme, Bertrand; Calvet, Jean-Christophe; Minvielle, Marie; Polcher, Jan; Fairbairn, David; Weedon, Graham P.

    2018-04-01

    Physically consistent descriptions of land surface hydrology are crucial for planning human activities that involve freshwater resources, especially in light of the expected climate change scenarios. We assess how atmospheric forcing data uncertainties affect land surface model (LSM) simulations by means of an extensive evaluation exercise using a number of state-of-the-art remote sensing and station-based datasets. For this purpose, we use the CO2-responsive ISBA-A-gs LSM coupled with the CNRM version of the Total Runoff Integrated Pathways (CTRIP) river routing model. We perform multi-forcing simulations over the Euro-Mediterranean area (25-75.5° N, 11.5° W-62.5° E, at 0.5° resolution) from 1979 to 2012. The model is forced using four atmospheric datasets. Three of them are based on the ERA-Interim reanalysis (ERA-I). The fourth dataset is independent from ERA-Interim: PGF, developed at Princeton University. The hydrological impacts of atmospheric forcing uncertainties are assessed by comparing simulated surface soil moisture (SSM), leaf area index (LAI) and river discharge against observation-based datasets: SSM from the European Space Agency's Water Cycle Multi-mission Observation Strategy and Climate Change Initiative projects (ESA-CCI), LAI of the Global Inventory Modeling and Mapping Studies (GIMMS), and Global Runoff Data Centre (GRDC) river discharge. The atmospheric forcing data are also compared to reference datasets. Precipitation is the most uncertain forcing variable across datasets, while the most consistent are air temperature and SW and LW radiation. At the monthly timescale, SSM and LAI simulations are relatively insensitive to forcing uncertainties. Some discrepancies with ESA-CCI appear to be forcing-independent and may be due to different assumptions underlying the LSM and the remote sensing retrieval algorithm. All simulations overestimate average summer and early-autumn LAI. Forcing uncertainty impacts on simulated river discharge are

  5. Postural steadiness and ankle force variability in peripheral neuropathy

    Science.gov (United States)

    Paxton, Roger J.; Feldman-Kothe, Caitlin; Trabert, Megan K.; Hitchcock, Leah N.; Reiser, Raoul F.; Tracy, Brian L.

    2015-01-01

    Introduction The purpose was to determine the effect of peripheral neuropathy (PN) on motor output variability for ankle muscles of older adults, and the relation between ankle motor variability and postural stability in PN patients. Methods Older adults with (O-PN) and without PN (O), and young adults (Y) underwent assessment of standing postural stability and ankle muscle force steadiness. Results O-PN displayed impaired ankle muscle force control and postural stability compared with O and Y groups. For O-PN, the amplitude of plantarflexor force fluctuations was moderately correlated with postural stability under no-vision conditions (r = 0.54, P = 0.01). Discussion The correlation of variations in ankle force with postural stability in PN suggests a contribution of ankle muscle dyscontrol to the postural instability that impacts physical function for older adults with PN. PMID:26284897

  6. A multidisciplinary methodological approach for slope stability assessment of an area prone to shallow landslides

    Science.gov (United States)

    Bordoni, Massimiliano; Meisina, Claudia; Valentino, Roberto; Bittelli, Marco; Battista Bischetti, Gian; Vercesi, Alberto; Chersich, Silvia; Giuseppina Persichillo, Maria

    2016-04-01

    Rainfall-induced shallow landslides are widespread slope instabilities phenomena in several hilly and mountainous contexts all over the world. Due to their high density of diffusion also in small areas, they can provoke important damages to terrains, infrastructures, buildings, and, sometimes, loss of human lives. Shallow landslides affect superficial soils of limited thickness (generally lower than 2 m), located above weathered or not bedrock levels. Their triggering mechanism is strictly linked to the hydrological response of the soils to rainfall events. Thus, it becomes fundamental a comprehensive analysis of the soil properties which can influence the susceptibility of a slope to shallow landslides. In this study, a multidisciplinary approach was followed for the characterization of the soils and the individuation of the triggering conditions in an area particularly prone to shallow failures, for slope stability assessment. This area corresponded to the hilly sector of North-Eastern Oltrepò Pavese (Lombardy Region, Northern Italy), where the density of shallow landslides is really high, reaching more than 36 landslides per km2. The soils of the study area were analyzed through a multidisciplinary characterization, which took into account for the main geotechnical, mechanical and mineralogical parameters and also for the main pedological features of the materials. This approach allowed for identifying the main features and the horizons which could influence the soil behavior in relation to the conditions that are preparatory to shallow landslides development. In a test-site slope, representative of the main geomorphological, geological and landslides distribution characteristics typical of the study area, a continuous in time monitoring of meteorological (rainfall amount, air temperature, air humidity, atmospheric pressure, net solar radiation, wind speed and direction) and hydrological (soil water content, pore water pressure) parameters was implemented. In

  7. Breath holding endurance: stability over time and relationship with self-assessed persistence

    Directory of Open Access Journals (Sweden)

    Daisy G.Y. Thompson-Lake

    2017-09-01

    Full Text Available Breath holding (BH endurance has been suggested as a measure of the distress tolerance that could predict the outcome of attempts to implement behavior changes, such as stopping smoking or illicit substance use. It is not known however, to what degree BH endurance is a variable trait that may vary depending on situational context, or a stable state characteristic. We measured BH in two groups of participants at baseline and 22 and 89 days (N = 62 and N = 41 post-baseline and in a third group at multiple times points across a 5-week period (N = 44. Participants also filled out a questionnaire created to assess their perceived persistence compared to peers. Correlations were found between baseline and final BH measures (r’s > 0.67, p’s < 0.0001 at all time points. When groups were combined, regardless of time point, Spearman’s rank correlation showed a strong positive correlation (rs = 0.66, p < 0.0001. Self-assessed persistence was not related to BH endurance. This study provides evidence of the stability of BH across time when tested under the same conditions in young adults. Further research is needed to clarify whether BH is linked to behavioral outcomes.

  8. Silver nanoparticles in complex biological media: assessment of colloidal stability and protein corona formation

    Energy Technology Data Exchange (ETDEWEB)

    Argentiere, Simona, E-mail: simona.argentiere@fondazionefilarete.com; Cella, Claudia, E-mail: claudia.cella@unimi.it [Fondazione Filarete (Italy); Cesaria, Maura, E-mail: maura.cesaria@le.infn.it [Università del Salento, Dipartimento di Matematica e Fisica “Ennio De Giorgi” (Italy); Milani, Paolo, E-mail: paolo.milani@mi.infn.it; Lenardi, Cristina, E-mail: cristina.lenardi@mi.infn.it [Università degli Studi di Milano, CIMAINA and Dipartimento di Fisica (Italy)

    2016-08-15

    Engineered silver nanoparticles (AgNPs) are among the most used nanomaterials in consumer products, therefore concerns are raised about their potential for adverse effects in humans and environment. Although an increasing number of studies in vitro and in vivo are being reported on the toxicity of AgNPs, most of them suffer from incomplete characterization of AgNPs in the tested biological media. As a consequence, the comparison of toxicological data is troublesome and the toxicity evaluation still remains an open critical issue. The development of a reliable protocol to evaluate interactions of AgNPs with surrounding proteins as well as to assess their colloidal stability is therefore required. In this regard, it is of importance not only to use multiple, easy-to-access and simple techniques but also to understand limitations of each characterization methods. In this work, the morphological and structural behaviour of AgNPs has been studied in two relevant biological media, namely 10 % FBS and MP. Three different techniques (Dynamic Light Scattering, Transmission Electron Microscopy, UV–Vis spectroscopy) were tested for their suitability in detecting AgNPs of three different sizes (10, 40 and 100 nm) coated with either citrate or polyvinylpyrrolidone. Results showed that UV–Vis spectroscopy is the most versatile and informative technique to gain information about interaction between AgNPs and surrounding proteins and to determine their colloidal stability in the tested biological media. These findings are expected to provide useful insights in characterizing AgNPs before performing any further in vitro/in vivo experiment.

  9. Assessment of Rock Slope Stability in Limestone Quarries in the Tournai's Region (Belgium) Using Structural Data

    Science.gov (United States)

    Tshibangu, Jean-Pierre; Deloge, K. Pierre-Alexandre; Deschamps, Benoît; Coudyzer, Christophe

    The Tournais region is characterised by famous outcrops of carboniferous limestone which is mined out for cement and raw material production. The four main quarries found in the Region, i.e. Gaurain-Ramecroix, Milieu, Antoing and Lemay; are owned by the three main cement producers in Belgium: Italcimenti, Holcim and CBR. The global production of limestone is about 20 millions tons per year, giving big pits with depths up to 150 m. With the growth of the pits, the quarries are approaching each other leading to the problem of managing the reserves contained in the separating walls and their mechanical stability. The limestone deposit is composed of different seams having varying thickness, chemical com- position and even mechanical properties. The deposit has an overall horizontal dip and is intersected by two main sets of discontinuities with a spacing of about 10 m or less. It is also crossed by a set of east to west faults but the quarries are implanted in the in between areas, so to not be crossed by these faults. The layers and specially the shallow ones are characterised by a typical karstic weathering giving open or filled cavities. This paper presents the global work quarried out in order to study the stability of the Lemays quarry. First a description of the orientation and spacing of discontinuities is presented, and an attempt made to correlate to the development of weathering. Mechanical laboratory tests have been performed and a qualification of the rock mass assessed. A coupled approach is then presented using a mining planning analysis and mechanical simulation (i.e. Finite Element method).

  10. Controlled assessment of the efficacy of occlusal stabilization splints on sleep bruxism.

    Science.gov (United States)

    van der Zaag, Jacques; Lobbezoo, Frank; Wicks, Darrel J; Visscher, Corine M; Hamburger, Hans L; Naeije, Machiel

    2005-01-01

    To assess the efficacy of occlusal stabilization splints in the management of sleep bruxism (SB) in a double-blind, parallel, controlled, randomized clinical trial. Twenty-one participants were randomly assigned to an occlusal splint group (n = 11; mean age = 34.2 +/- 13.1 years) or a palatal splint (ie, an acrylic palatal coverage) group (n = 10; mean age = 34.9 +/- 11.2 years). Two polysomnographic recordings that included bilateral masseter electromyographic activity were made: one prior to treatment, the other after a treatment period of 4 weeks. The number of bruxism episodes per hour of sleep (Epi/h), the number of bursts per hour (Bur/h), and the bruxism time index (ie, the percentage of total sleep time spent bruxing) were established as outcome variables at a 10% maximum voluntary contraction threshold level. A general linear model was used to test both the effects between splint groups and within the treatment phase as well as their interaction for each outcome variable. Neither occlusal stabilization splints nor palatal splints had an influence on the SB outcome variables or on the sleep variables measured on a group level. In individual cases, variable outcomes were found: Some patients had an increase (33% to 48% of the cases), while others showed no change (33% to 48%) or a decrease (19% to 29%) in SB outcome variables. The absence of significant group effects of splints in the management of SB indicates that caution is required when splints are indicated, apart from their role in the protection against dental wear. The application of splints should therefore be considered at the individual patient level.

  11. Selective effects of different fatigue protocols on the function of upper body muscles assessed through the force-velocity relationship.

    Science.gov (United States)

    García-Ramos, Amador; Torrejón, Alejandro; Feriche, Belén; Morales-Artacho, Antonio J; Pérez-Castilla, Alejandro; Padial, Paulino; Jaric, Slobodan

    2018-02-01

    This study explored the feasibility of the force-velocity relationship (F-V) to detect the acute effects of different fatigue protocols on the selective changes of the maximal capacities of upper body muscles to produce force, velocity, and power. After determining the bench press one-repetition maximum (1RM), participants' F-V relationships were assessed during the bench press throw exercise on five separate sessions after performing one of the following fatiguing protocols: 60%1RM failure, 60%1RM non-failure, 80%1RM failure, 80%1RM non-failure, and no-fatigue. In the non-failure protocols, participants performed half the maximum number of repetitions than in their respective failure protocols. The main findings revealed that (1) all F-V relationships were highly linear (median r = 0.997 and r = 0.982 for averaged across participants and individual data, respectively), (2) the fatiguing protocols were ranked based on the magnitude of power loss as follows: 60%1RM failure > 80%1RM failure > 60%1RM non-failure > 80%1RM non-failure, while (3) the assessed maximum force and velocity outputs showed a particularly prominent reduction in the protocols based on the lowest and highest levels of fatigue (i.e., 80%1RM non-failure and 60%1RM failure), respectively. The results support the use of F-V to assess the effects of fatigue on the distinctive capacities of the muscles to produce force, velocity, and power output while performing multi-joint tasks, while the assessed maximum force and velocity capacities showed a particularly prominent reduction in the protocols based on the lowest and highest levels of fatigue (i.e., 80%1RM non-failure and 60%1RM failure), respectively.

  12. Assessment of navigation cues with proximal force sensing during endovascular catheterization.

    Science.gov (United States)

    Rafii-Taril, Hedyeh; Payne, Christopher J; Riga, Celia; Bicknell, Colin; Lee, Su-Lin; Yang, Guang-Zhong

    2012-01-01

    Despite increased use of robotic catheter navigation systems for endovascular intervention procedures, current master-slave platforms have not yet taken into account dexterous manipulation skill used in traditional catheterization procedures. Information on tool forces applied by operators is often limited. A novel force/torque sensor is developed in this paper to obtain behavioural data across different experience levels and identify underlying factors that affect overall operator performance. The miniature device can be attached to any part of the proximal end of the catheter, together with a position sensor attached to the catheter tip, for relating tool forces to catheter dynamics and overall performance. The results show clear differences in manipulation skills between experience groups, thus providing insights into different patterns and range of forces applied during routine endovascular procedures. They also provide important design specifications for ergonomically optimized catheter manipulation platforms with added haptic feedback while maintaining natural skills of the operators.

  13. An Enduring Framework for Assessing the Contributions of Force Structure to a Coercive Strategy

    National Research Council Canada - National Science Library

    Beene, Eric

    2001-01-01

    The US Department of Defense is still struggling to define itself in the post Cold War age, over a decade after the new period has begun With a strategy and force structure review occurring on average...

  14. Intention stability assessed using residual change scores moderates the intention-behaviour association: a prospective cohort study.

    Science.gov (United States)

    Rowan, Alicia A; McDermott, Máirtín S; Allen, Mark S

    2017-12-01

    Intention stability is considered to be one of the key pre-requisites for a strong association between intention and behaviour. It has been claimed, however, that studies examining the moderating impact of intention stability may be invalid, as they have relied on statistically inferior methods. Residual change scores have been suggested as a more appropriate method of measuring change (or lack thereof) in constructs. The aim of the current study, therefore, is to test whether intention stability, calculated using residual change scores, moderates the intention-physical activity behaviour association. A total of 163 participants (124 women, 39 men) completed questionnaires online at three time points separated by 14 day intervals. The moderating impact of intention stability was assessed using multiple linear regression followed up using simple slope analyses to identify the direction of any effect. The interaction of intention and intention stability was found to significantly improve the overall model fit. Intentions had a stronger positive association with behaviour when intentions were more stable than when they were more unstable. However, sensitivity analyses revealed that the association was not robust and reduced to non-significant with the removal of potential multivariate outliers. Future research should use residual change scores as the preferred method of assessing intention stability.

  15. 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...m3 micrograms per cubic meter US United States USACE United States Army Corp of Engineers USC United States Code USCB United States Census Bureau...effects and annoyance in that very few flight operations and ground engine runs occur between 2200 hours and 0700 hours. BMPs include restricting the

  16. Energy to the Edge (E2E) Equipment Assessment U.S. Army Rapid Equipping Force

    Science.gov (United States)

    2015-05-01

    84 Contents Energy to the Edge • U.S. Army Rapid Equipping Force U.S. Army Rapid Equipping Force 1.0 Executive Summary Executive Summary U.S. Army... audiovisual equipment. • Once radiant barrier liner is inserted, the process of subsequent setups • Cables for lighting and outlets are located...behind the internal barrier • The shelter comes with organic audiovisual equipment. b. • • This shelter has a different setup and tear down process

  17. Environmental Assessment: Improvements to Silver Flag Training Area at Tyndall Air Force Base, Florida

    Science.gov (United States)

    2013-01-01

    Command ACM asbestos-containing materials AICUZ Air Installation Compatible Use Zone AFB Air Force Base AFI Air Force Instruction APZ Accident...T E G2/S2 Wet prairies, wet flatwoods, ditches, seepage slopes, cypress swamps White-flowered wild petunia Ruellia noctiflora E G2/S2 Wet...Procedures (SOPs) 4 or 5 of the Tyndall AFB ICRMP are required to be implemented in the event that cultural materials are discovered during

  18. Essential equivalence: the objectives and requirements of a stategic nuclear policy: a perspective on the evolution of US strategic nuclear policy, and an assessment of present and emerging US strategic policy and force stucture options

    International Nuclear Information System (INIS)

    Hughes, P.C.

    1979-01-01

    This study provides a discussion of the origins and evolution of US strategic nuclear policy, the objectives an requirements of US nuclear forces, and an assessment of present and emerging US stategic nuclear policy and force structure options. It identifies the distinctive phases of US strategic nuclear policy, the conditions of the military environments in which those policies were developed, the interaction of US-Soviet strategic force and arms control processes during these phases, and the domestic debates which have accompanied US strategic nuclear policy developments. In particular, the study focuses on the major contending views which continue to characterize the debate concerning US strategic nuclear policy. The study assesses the implications of the contending views represented in what is commonly referred to as the counterforce-countervalue debate, particularly as they relate to the perception of what constitutes a credible US deterrent posture, and the corresponding alternatives that these views bring with them for making US strategic nuclear policy and force structure decisions. The arms control process, in general, and SALT I and SALT II in particular, is discussed as an integral and dynamic component of the strategic debate, fundamentally affecting the nation's security policies. The implications of modern weapons technology, and the problems inherent in preserving strategic stability between adversary nations with asymmetries in military force structures and doctrines, are also discussed. Further, the study focuses on the question of whether or not nuclear superiority can be considered relevant under the contemporary international conditions

  19. The effectiveness of FES-evoked EMG potentials to assess muscle force and fatigue in individuals with spinal cord injury.

    Science.gov (United States)

    Ibitoye, Morufu Olusola; Estigoni, Eduardo H; Hamzaid, Nur Azah; Wahab, Ahmad Khairi Abdul; Davis, Glen M

    2014-07-14

    The evoked electromyographic signal (eEMG) potential is the standard index used to monitor both electrical changes within the motor unit during muscular activity and the electrical patterns during evoked contraction. However, technical and physiological limitations often preclude the acquisition and analysis of the signal especially during functional electrical stimulation (FES)-evoked contractions. Hence, an accurate quantification of the relationship between the eEMG potential and FES-evoked muscle response remains elusive and continues to attract the attention of researchers due to its potential application in the fields of biomechanics, muscle physiology, and rehabilitation science. We conducted a systematic review to examine the effectiveness of eEMG potentials to assess muscle force and fatigue, particularly as a biofeedback descriptor of FES-evoked contractions in individuals with spinal cord injury. At the outset, 2867 citations were identified and, finally, fifty-nine trials met the inclusion criteria. Four hypotheses were proposed and evaluated to inform this review. The results showed that eEMG is effective at quantifying muscle force and fatigue during isometric contraction, but may not be effective during dynamic contractions including cycling and stepping. Positive correlation of up to r = 0.90 (p peak-to-peak amplitude of the eEMG and the decline in the force output during fatiguing isometric contractions has been reported. In the available prediction models, the performance index of the eEMG signal to estimate the generated muscle force ranged from 3.8% to 34% for 18 s to 70 s ahead of the actual muscle force generation. The strength and inherent limitations of the eEMG signal to assess muscle force and fatigue were evident from our findings with implications in clinical management of spinal cord injury (SCI) population.

  20. The Effectiveness of FES-Evoked EMG Potentials to Assess Muscle Force and Fatigue in Individuals with Spinal Cord Injury

    Directory of Open Access Journals (Sweden)

    Morufu Olusola Ibitoye

    2014-07-01

    Full Text Available The evoked electromyographic signal (eEMG potential is the standard index used to monitor both electrical changes within the motor unit during muscular activity and the electrical patterns during evoked contraction. However, technical and physiological limitations often preclude the acquisition and analysis of the signal especially during functional electrical stimulation (FES-evoked contractions. Hence, an accurate quantification of the relationship between the eEMG potential and FES-evoked muscle response remains elusive and continues to attract the attention of researchers due to its potential application in the fields of biomechanics, muscle physiology, and rehabilitation science. We conducted a systematic review to examine the effectiveness of eEMG potentials to assess muscle force and fatigue, particularly as a biofeedback descriptor of FES-evoked contractions in individuals with spinal cord injury. At the outset, 2867 citations were identified and, finally, fifty-nine trials met the inclusion criteria. Four hypotheses were proposed and evaluated to inform this review. The results showed that eEMG is effective at quantifying muscle force and fatigue during isometric contraction, but may not be effective during dynamic contractions including cycling and stepping. Positive correlation of up to r = 0.90 (p < 0.05 between the decline in the peak-to-peak amplitude of the eEMG and the decline in the force output during fatiguing isometric contractions has been reported. In the available prediction models, the performance index of the eEMG signal to estimate the generated muscle force ranged from 3.8% to 34% for 18 s to 70 s ahead of the actual muscle force generation. The strength and inherent limitations of the eEMG signal to assess muscle force and fatigue were evident from our findings with implications in clinical management of spinal cord injury (SCI population.

  1. Preliminary assessment of potential underground stability (wedge and spalling) at Forsmark, Simpevarp and Laxemar sites

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Derek [Univ. of Alberta, Edmonton (Canada). Geotechnical Engineering

    2005-12-15

    In SKB's Underground Design Premises the objective in the early design phase is to estimate if there is sufficient space for the repository at a site. One of the conditions that could limit the space available is stability of the underground openings, i.e., deposition tunnels and deposition boreholes. The purpose of this report is to provide a preliminary assessment of the potential for wedge instability and spalling that may be encountered at the Forsmark, Simpevarp and Laxemar sites based on information from the site investigations program up to July 30, 2004. The rock mass spalling strength was defined using the in-situ results from SKB's Aespoe Pillar Stability Experiment and AECL's Mine-by Experiment. These experiments suggest that the rock mass spalling strength for crystalline rocks can be estimated as 0.57 of the mean laboratory uniaxial compressive strength. A probability-based methodology utilizing this in-situ rock mass spalling strength has been developed for assessing the risk for spalling in a repository at the Forsmark, Simpevarp and Laxemar sites. The in-situ stresses and the uniaxial compressive strength data from these sites were used as the bases for the analyses. Preliminary findings from all sites suggest that, generally, the risk for spalling increases as the depth of the repository increases, simply because the stress magnitudes increase with depth. The depth at which the risk for spalling is significant, depends on the individual sites which are discussed below. The greatest uncertainty in the spalling analyses for Forsmark is related to the uncertainty in the horizontal stress magnitudes and associated stress gradients with depth. The confidence in these analyses can only be increased by increasing the confidence in the stress and geology model for the site. From the analyses completed it appears that spalling in the deposition tunnels can be controlled by orienting the tunnels approximately parallel to the maximum horizontal

  2. Assessment of myeloperoxidase activity at different force levels in gingival crevicular fluid during initial phase of orthodontic tooth movement

    Directory of Open Access Journals (Sweden)

    Honey Gurbaxani

    2017-01-01

    Full Text Available Background: Orthodontic movements promote remodeling of the alveolar bone, which is mediated by inflammatory reactions such as characterized by vascular changes and infiltration of leukocytes. Changes in the periodontium occur, depending on the magnitude, duration, and direction of applied force. These changes are often seen in the saliva and gingival fluids through the various substances secreted in them. Aim: The present study aimed to assess myeloperoxidase (MPO activity at different force levels in gingival crevicular fluid (GCF during the initial phase of orthodontic tooth movement by varying the effective force levels to 50, 75, 100, and 150 g. Materials and Methods: A total of thirty participants between the age groups of 18–25 years requiring upper first premolar extractions were included in the study. They were divided into three groups (I, II, and III of ten individuals each, again subdivided into two Subgroups A and B depending on the amount of force applied to the canine. Subgroup A of all the three groups used 150 g, whereas Subgroup B used 50, 75, and 100 g of force, respectively. GCF was collected at 2 h, 7 days, and 14 days of force application. Statistical Analysis: Paired t-test and ANOVA test were used to provide the descriptive statistics of mean optical density to detect the presence of MPO in GCF. Results and Conclusion: There was a highly significant increase in the MPO levels in the GCF at 14th day after force application which can be correlated to the onset of inflammatory reactions in the periodontium.

  3. Rule Extraction Based on Extreme Learning Machine and an Improved Ant-Miner Algorithm for Transient Stability Assessment.

    Science.gov (United States)

    Li, Yang; Li, Guoqing; Wang, Zhenhao

    2015-01-01

    In order to overcome the problems of poor understandability of the pattern recognition-based transient stability assessment (PRTSA) methods, a new rule extraction method based on extreme learning machine (ELM) and an improved Ant-miner (IAM) algorithm is presented in this paper. First, the basic principles of ELM and Ant-miner algorithm are respectively introduced. Then, based on the selected optimal feature subset, an example sample set is generated by the trained ELM-based PRTSA model. And finally, a set of classification rules are obtained by IAM algorithm to replace the original ELM network. The novelty of this proposal is that transient stability rules are extracted from an example sample set generated by the trained ELM-based transient stability assessment model by using IAM algorithm. The effectiveness of the proposed method is shown by the application results on the New England 39-bus power system and a practical power system--the southern power system of Hebei province.

  4. Optimization of Forced Degradation Using Experimental Design and Development of a Stability-Indicating Liquid Chromatographic Assay Method for Rebamipide in Bulk and Tablet Dosage Form

    Directory of Open Access Journals (Sweden)

    Sandeep SONAWANE

    2016-09-01

    Full Text Available A novel stability-indicating RP-HPLC assay method was developed and validated for quantitative determination of rebamipide in bulk and tablet dosage form. Rebamipide (drug and drug product solutions were exposed to acid and alkali hydrolysis, thermal stress, oxidation by hydrogen peroxide and photodegradation. Experimental design has been used during forced degradation to determine significant factors responsible for degradation and to obtain optimal degradation conditions. In addition, acid and alkali hydrolysis was performed using a microwave oven. The chromatographic method employed the HiQ sil C-18HS (250 × 4.6 mm; 5 μm column with mobile phase consisting of 0.02 M potassium phosphate (pH adjusted to 6.8 and methanol (40:60, v/v and the detection was performed at 230 nm. The procedure was validated for specificity, linearity, accuracy, precision and robustness. There was no interference observed of excipients and degradation products in the determination of the active pharmaceutical ingredient. The method showed good accuracy and precision (intra and inter day and the response was linear in a range from 0.5 to 5 μg mL−1. The method was found to be simple and fast with less trial and error experimentation by making use of experimental design. Also, it proved that microwave energy can be used to expedite hydrolysis of rebamipide.

  5. Complication assessment and prevention strategies using midfoot fusion bolt for medial column stabilization in Charcot's osteoarthropathy

    DEFF Research Database (Denmark)

    Mehlhorn, Alexander T; Walther, Markus; Iblher, Niklas

    2016-01-01

    and stabilization using midfoot fusion bolt and lateral lag screws. Age, gender, presence of preoperative osteomyelitis or ulcer, number of complications and operative revisions, Hba1c value, consolidation of arthrodesis, presence of a load-bearing foot and period to bolt dislocation was assessed. The mean follow......-up was 21.4±14.6 (mean±SDM) months, 64% of patients suffered from diabetes with a preoperative Hba1c of 8.5±2.4. The mean number of revisions per foot was 3.6±4.1. Bolt dislocation was seen in 57% of the patients following 11.3±8.5 months; in 75% of these patients bony healing occurred before dislocation....... There was a significant association between preoperative increased Hba1c value, presence of preoperative ulcer and wound infection. Healing of arthrodesis was demonstrated in 57% and a permanent weight-bearing foot without recurrent ulcer was achieved in 79%. The early and late postoperative complications could...

  6. Ultra-high resolution four dimensional geodetic imaging of engineered structures for stability assessment

    Science.gov (United States)

    Bawden, Gerald W.; Bond, Sandra; Podoski, J. H.; Kreylos, O.; Kellogg, L. H.

    2012-01-01

    We used ground-based Tripod LiDAR (T-LiDAR) to assess the stability of two engineered structures: a bridge spanning the San Andreas fault following the M6.0 Parkfield earthquake in Central California and a newly built coastal breakwater located at the Kaumālapa`u Harbor Lana'i, Hawaii. In the 10 weeks following the earthquake, we found that the surface under the bridge shifted 7.1 cm with an additional 2.6 cm of motion in the subsequent 13 weeks, which deflected the bridge's northern I-beam support 4.3 cm and 2.1 respectively; the bridge integrity remained intact. T-LiDAR imagery was collected after the completion of armored breakwater with 817 35-ton interlocking concrete armor units, Core-Locs®, in the summers of 2007, 2008 and 2010. We found a wide range of motion of individual Core-Locs, from a few centimeters to >110 cm along the ocean side of the breakwater, with lesser movement along the harbor side.

  7. Assessing the stability of soil organic matter by fractionation and 13C isotope techniques

    Science.gov (United States)

    Larionova, A. A.; Zolotareva, B. N.; Kvitkina, A. K.; Evdokimov, I. V.; Bykhovets, S. S.; Stulin, A. F.; Kuzyakov, Ya. V.; Kudeyarov, V. N.

    2015-02-01

    Carbon pools of different stabilities have been separated from the soil organic matter of agrochernozem and agrogray soil samples. The work has been based on the studies of the natural abundance of the carbon isotope composition by C3-C4 transition using the biokinetic, size-density, and chemical fractionation (6 M HCl hydrolysis) methods. The most stable pools with the minimum content of new carbon have been identified by particle-size and chemical fractionation. The content of carbon in the fine fractions has been found to be close to that in the nonhydrolyzable residue. This pool makes up 65 and 48% of Corg in the agrochernozems and agrogray soils, respectively. The combination of the biokinetic approach with particle-size fractionation or 6 M HCl hydrolysis has allowed assessing the size of the medium-stable organic carbon pool with a turnover time of several years to several decades. The organic matter pool with this turnover rate is usually identified from the variation in the 13C abundance by C3-C4 transition. In the agrochernozems and agrogray soils, the medium-stable carbon pool makes up 35 and 46% of Corg, respectively. The isotope indication may be replaced by a nonisotope method to significantly expand the study of the inert and mediumstable organic matter pools in the geographical aspect, but this requires a comparative analysis of particle-size and chemical fractionation data for all Russian soils.

  8. Comparative water quality assessment between a young and a stabilized hydroelectric reservoir in Aliakmon River, Greece.

    Science.gov (United States)

    Samiotis, Georgios; Trikoilidou, Eleni; Tsikritzis, Lazaros; Amanatidou, Elisavet

    2018-03-20

    In this work, a comparative study on the water quality characteristics of two in-line water reservoirs (artificial lakes) in Aliakmon River (Western Macedonia, Greece) is performed. Polyfytos Reservoir and Ilarion Reservoir were created in 1975 and 2012 respectively, in order to serve the homonymous hydroelectric stations. In young artificial lakes, severe deterioration of water quality may occur; thus, the monitoring and assessment of their water quality characteristics and their statistical interpretation are of great importance. In order to evaluate any temporal or spatial variations and to characterize water quality of these two in-line water reservoirs, water quality data from measurements conducted from 2012 to 2015 were statistically processed and interpreted by using a modified National Sanitation Foundation water quality index (WQI). The water physicochemical characteristics of the two reservoirs were found to be generally within the legislation limits, with relatively small temporal and spatial variations. Although Polyfytos Reservoir showed no significant deviations of its water quality, Ilarion Reservoir exhibited deviations in total Kjeldahl nitrogen, nitrite nitrogen, total suspended solids, and turbidity due to the inundated vegetation decomposition. The conducted measurements and the use of the modified NSFWQI revealed that during the inundation period of Ilarion Reservoir, its water quality was "moderate" and that the deviations were softened through time, leading to "good" water quality during its maturation period. Three years since the creation of Ilarion Reservoir, water quality does not match that of Aliakmon River (feeding water) or that of the stabilized reservoir (Polyfytos Reservoir), whose quality is characterized as "high." The use of a WQI, such as the proposed modified NSFWQI, for evaluating water quality of each sampling site and of an entire water system proved to be a rapid and relatively accurate assessment tool.

  9. VSC Input-Admittance Modeling and Analysis Above the Nyquist Frequency for Passivity-Based Stability Assessment

    DEFF Research Database (Denmark)

    Harnefors, Lennart; Finger, Raphael; Wang, Xiongfei

    2017-01-01

    The interconnection stability of a gridconnected voltage-source converter (VSC) can be assessed via the dissipative properties of its input admittance. In this paper, the modeling of the current control loop is revisited with the aim to improve the accuracy of the input-admittance model above...

  10. United States Air Force Academy Educational Outcomes Assessment Working Group. Phase 2

    National Research Council Canada - National Science Library

    Porter, David

    1997-01-01

    This publication provides an account of educational outcomes assessment activity undertaken by seven assessment teams under the Phase II Charter of the Dean of the Faculty's Educational Outcomes Assessment Working Group...

  11. Drivers of 2016 record Arctic warmth assessed using climate simulations subjected to Factual and Counterfactual forcing

    Directory of Open Access Journals (Sweden)

    Lantao Sun

    2018-03-01

    Full Text Available A suite of historical atmospheric model simulations is described that uses a hierarchy of global boundary forcings designed to inform research on the detection and attribution of weather and climate-related extremes. In addition to experiments forced by actual variations in sea surface temperature, sea ice concentration, and atmospheric chemical composition (so-called Factual experiments; additional (Counterfactual experiments are conducted in which the boundary forcings are adjusted by removing estimates of long-term climate change. A third suite of experiments are identical to the Factual runs except that sea ice concentrations are set to climatological conditions (Clim-Polar experiments. These were used to investigate the cause for extremely warm Arctic surface temperature during 2016.Much of the magnitude of surface temperature anomalies averaged poleward of 65°N in 2016 (3.2 ± 0.6 °C above a 1980–89 reference is shown to have been forced by observed global boundary conditions. The Factual experiments reveal that at least three quarters of the magnitude of 2016 annual mean Arctic warmth was forced, with considerable sensitivity to assumptions of sea ice thickness change. Results also indicate that 30–40% of the overall forced Arctic warming signal in 2016 originated from drivers outside of the Arctic. Despite such remote effects, the experiments reveal that the extreme magnitude of the 2016 Arctic warmth could not have occurred without consideration of the Arctic sea ice loss. We find a near-zero probability for Arctic surface temperature to be as warm as occurred in 2016 under late-19th century boundary conditions, and also under 2016 boundary conditions that do not include the depleted Arctic sea ice. Results from the atmospheric model experiments are reconciled with coupled climate model simulations which lead to a conclusion that about 60% of the 2016 Arctic warmth was likely attributable to human-induced climate change

  12. Forced Adoption of IFRS by Czech Non-Listed Companies: An Assessment of Benefits and Costs

    OpenAIRE

    David Procházka

    2016-01-01

    The paper deals with the effects of IFRS adoption by a specific group of companies. It focuses on the so-called forced IFRS adopters, which are such private (non-listed) companies that (a) are forced to adopt the IFRS (because their parent prepares IFRS consolidated statements) and simultaneously (b) are not permitted by the regulatory framework of a given jurisdiction to apply the IFRS in their individual financial statements on a  voluntary basis. In particular, benefits and costs connected...

  13. A Stability-Indicating HPLC-DAD Method for Determination of Ferulic Acid into Microparticles: Development, Validation, Forced Degradation, and Encapsulation Efficiency

    Directory of Open Access Journals (Sweden)

    Jessica Mendes Nadal

    2015-01-01

    Full Text Available A simple stability-indicating HPLC-DAD method was validated for the determination of ferulic acid (FA in polymeric microparticles. Chromatographic conditions consisted of a RP C18 column (250 mm × 4.60 mm, 5 μm, 110 Å using a mixture of methanol and water pH 3.0 (48 : 52 v/v as mobile phase at a flow rate of 1.0 mL/min with UV detection at 320 nm. The developed method was validated as per ICH guidelines with respect to specificity, linearity, limit of quantification, limit of detection, accuracy, precision, and robustness provided suitable results regarding all parameters investigated. The calibration curve was linear in the concentration range of 10.0–70.0 μg/mL with a correlation coefficient >0.999. Precision (intraday and interday was demonstrated by a relative standard deviation lower than 2.0%. Accuracy was assessed by the recovery test of FA from polymeric microparticles (99.02% to 100.73%. Specificity showed no interference from the components of polymeric microparticles or from the degradation products derived from acidic, basic, and photolytic conditions. In conclusion, the method is suitable to be applied to assay FA as bulk drug and into polymeric microparticles and can be used for studying its stability and degradation kinetics.

  14. assessment of yield stability in sorghum abstract résumé

    African Journals Online (AJOL)

    Administrator

    environment followed by combined analysis of variance using IRRISTAT for Windows Version. 4.0. (IRRI, 1999). Because the genotype-by-environment interaction was significant, five out of the nine stability models, which were grouped into four groups and latter, divided in to three types of stability by Lin et al. (1986), were ...

  15. Assessment of read and write stability for 6T SRAM cell based on charge plasma DLTFET

    Science.gov (United States)

    Anju; Yadav, Shivendra; Sharma, Dheeraj

    2018-03-01

    To overcome the process variations due to random dopant fluctuations (RDFs) and complex annealing techniques a charge plasma based doping less TFET (CP-DLTFET) device has been proposed for designing of 6T SRAM cell. The proposed device also benefited by subthreshold slope, low leakage current, and low power supply. In this paper, to avoid the dependency of stability parameters of SRAM cell to supply voltage (Vdd), here N-curve metrics has been analyzed to determine read and write stability. Because N-curve provides stability analysis in terms of voltage and current as well as it gives combine stability analysis with the facility of an inline tester. Further, analyzing the N-curve metrics for different Vdd, cell ratio, and pull-up ratio assist in designing the configuration of transistors for the better read and write stability. Power metrics of N-curve gives the knowledge about read and write stability instead of using four metrics (SINM, SVNM, WTV, and WTI) of N-curve. Finally, in the 6T CP-DLTFET SRAM cell, read and write stability is tested by the interface trap charges (ITCs). The performance parameter of the 6T CP-DLTFET SRAM cell provides considerable read and write stability with less fabrication complexity.

  16. Prospects for stability in a nuclear subcontinent

    International Nuclear Information System (INIS)

    Rajagopal, S; Chari, Sridhar K.

    2003-01-01

    This book explore the prospects for stability in a nuclear sub-continent. The nonproliferation regimes and nuclear threat reduction, nonproliferation regimes and south asia - is there a meeting point?; maintaining a threshold of strategic autonomy at least cost: continuity in the evolution of India's nuclear policies; role of nuclear doctrines and the state of the armed forces in South Asia; nuclear weapons, deterrence and stability in the international system: South Asian dynamics; assessing China's Asian role and security policies; Kargil war to current threat of war: prospects for stability; discussion; international terrorism and its impact on South Asian stability; a view from Bangladesh etc. are some of the topics covered

  17. Assessment of zerovalent iron for stabilization of chromium, copper, and arsenic in soil

    International Nuclear Information System (INIS)

    Kumpiene, Jurate; Ore, Solvita; Renella, Giancarlo; Mench, Michel; Lagerkvist, Anders; Maurice, Christian

    2006-01-01

    Stabilization of soil contaminated with trace elements is a remediation practice that does not reduce the total content of contaminants, but lowers the amounts of mobile and bioavailable fractions. This study evaluated the efficiency of Fe to reduce the mobility and bioavailability of Cr, Cu, As and Zn in a chromated copper arsenate (CCA)-contaminated soil using chemical, biochemical and biotoxicity tests. Contaminated soil was stabilized with 1% iron grit. This treatment decreased As and Cr concentrations in leachates (by 98% and 45%, respectively), in soil pore water (by 99% and 94%, respectively) and in plant shoots (by 84% and 95%, respectively). The stabilization technique also restored most of analyzed soil enzyme activities and reduced microbial toxicity, as evaluated by the BioTox TM test. After stabilization, exchangeable and bioaccessible fractions of Cu remained high, causing some residual toxicity in the treated soil. - Zerovalent iron effectively reduces mobility and bioavailability of As and Cr, but does not adequately stabilize Cu

  18. U.S. Force Posture Strategy in the Asia Pacific Region: An Independent Assessment

    Science.gov (United States)

    2012-06-27

    is important to note that the Philippine Senate in 1992 changed the constitution to prohibit permanent bases; U.S. forces‘ access is based on the...Expeditionary Force MILCON—Military Construction MOU—Memorandum of Understanding NAFTA —North American Free Trade Agreement NDAA—National Defense

  19. Environmental Assessment for the Construction of a Photovoltaic Solar Array at Laughlin Air Force Base, Texas

    Science.gov (United States)

    2011-10-01

    Softball Field FAMCamp Golf Course Club House Tennis Court GENERAL PLAN Update | Laughlin Air Force Base, Texas 4-9 CoMPonEnT PLAns Legend[ FIGuRE 4-3...Golf Course, FAMCamp RV Park, several baseball/ softball fields, a paintball field, an outdoor skeet shooting range, a multi-sport track and field

  20. Joint Maneuver Test Range on Eglin Air Force Base, Florida Final Environmental Assessment

    Science.gov (United States)

    2009-12-14

    ir Force B ase, Florida Page 3-2 Final E nvironm ental A ssessm ent A ffected E nvironm ent W ater R esources Figure 3-1. Physical and...nvironm ent W ater R esources Figure 3-2. Physical and Biological Resources Within Range B-9 Existing Components 14. Hills!Qoss Slope Legend --Creek

  1. Technical and economic assessment for asbestos abatement within Facility 20470, Wright-Patterson Air Force Base, Ohio

    International Nuclear Information System (INIS)

    Gibson, S.M.; Ogle, R.B.

    1988-03-01

    This report presents the results of a technical and economic assessment of available alternatives for asbestos abatement within Facility 20470 at the Wright-Patterson Air Force Base in Dayton, Ohio. Each alternative was screened on the basis of technical feasibility, environmental impact, economics, and fulfillment of the IRP goals. Four alternatives for study are: establishing a special operations and maintenance program; enclosure; encapsulation with sealants; and removal, disposal, and replacement. Each of these alternatives was assessed for capability to control the release of asbestos fibers within Facility 20470. Alternatives 1 and 4 were determined to be acceptable, while Alternatives 2 and 3 were found to be unacceptable. 2 refs., 6 figs

  2. 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:

  3. Specificity of HPLC to assess the chemical stability based on partenine from Parthenium hysterophorus L. powdered dry foliage (escoba amarga)

    International Nuclear Information System (INIS)

    Saucedo Hernandez, Yanelis; Mohamad Safa, Bassam; Gonzalez Bedia, Mirtha Mayra

    2010-01-01

    It is required a specific analysis technique allowing the follow-up to stability study intrinsic of Parthenium hysterophorus L. (escoba amarga) powdered dry foliage to achieve in a pharmaceutical way a antiparasitic usefulness with the quality, safety and effectiveness demanded requirements. High performance liquid chromatography was applied to P. hysterophorus degraded samples under degradation conditions in an oxidative, basic and acid medium. The analysis technique specificity was assessed to detect the interest component without interferences of its degradation products and its possible usefulness in studies on solid stability in the plant powder

  4. Study of the weakly bound 26F nucleus to probe the evolution of nuclear forces near the limits of particle stability

    International Nuclear Information System (INIS)

    Lepailleur, Alexandre

    2013-01-01

    Nuclear forces play a decisive role to account for the evolution of the nuclear structure and to fix the limits of particle stability. The study of neutron-rich nuclei is particularly important to determine these limits and to reveal the disappearance or emergence of new shell gaps far from stability. We studied the weakly bound neutron-rich 26 F in order to probe the πd 5/2 xνd 3/2 interaction. Indeed this nucleus can be modeled as a closed core of 24 O on top of which a single deeply bound proton in πd 5/2 interacts with an unbound neutron in νd 3/2 . This coupling gives rise to the quadruplet of states J = 1, 2, 3, 4 of positive parity. Their determination would allow us to quantify the intensity of the πd 5/2 xνd 3/2 interaction. Among these states, the J = 1 (ground state) and J = 2 (first excited state) were already known. The search for the J = 4 state has been investigated by our group at GANIL through a β-decay experiment. The nuclei of 26 F were produced by the fragmentation of a 36 S beam and selected using the LISE spectrometer. They were then implanted in a Double Sided Stripped Silicon Detector that gave us the opportunity to achieve spatial and time correlations between the implanted ions and the products of the decays (β and γ rays). Moreover we were able to observe the delayed M3 γ transition from the isomeric J = 4 state to the J = 1 ground state and thus obtained the excitation energy of 643.4 keV for this isomeric state. We also determined several new states in 25-26 Ne that were fed by the β-decay of the ground and isomeric state of 26 F. We extracted an isomeric ratio of about 40% and adjusted the previously determined mass of 26 F according to this value, leading to ΔM = 270 (50) keV. The J = 3 state has been populated ad studied at GSI by means of a one proton knock-out reaction from a radioactive 27 Ne beam to produce the 26 F in its unbound states. When the 26 F is produced in its unbound state J = 3, it decays in 25 F + n. The

  5. The American Psychological Association Task Force assessment of violent video games: Science in the service of public interest.

    Science.gov (United States)

    Calvert, Sandra L; Appelbaum, Mark; Dodge, Kenneth A; Graham, Sandra; Nagayama Hall, Gordon C; Hamby, Sherry; Fasig-Caldwell, Lauren G; Citkowicz, Martyna; Galloway, Daniel P; Hedges, Larry V

    2017-01-01

    A task force of experts was convened by the American Psychological Association (APA) to update the knowledge and policy about the impact of violent video game use on potential adverse outcomes. This APA Task Force on Media Violence examined the existing literature, including the meta-analyses in the field, since the last APA report on media violence in 2005. Because the most recent meta-analyses were published in 2010 and reflected work through 2009, the task force conducted a search of the published studies from 2009-2013. These recently published articles were scored and assessed by a systematic evidentiary review, followed by a meta-analysis of the high utility studies, as documented in the evidentiary review. Consistent with the literature that we reviewed, we found that violent video game exposure was associated with: an increased composite aggression score; increased aggressive behavior; increased aggressive cognitions; increased aggressive affect, increased desensitization, and decreased empathy; and increased physiological arousal. The size of the effects was similar to that in prior meta-analyses, suggesting a stable result. Our task force concluded that violent video game use is a risk factor for adverse outcomes, but found insufficient studies to examine any potential link between violent video game use and delinquency or criminal behavior. Our technical report is the basis of this article. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. Chemical stability and in chemico reactivity of 24 fragrance ingredients of concern for skin sensitization risk assessment.

    Science.gov (United States)

    Avonto, Cristina; Wang, Mei; Chittiboyina, Amar G; Vukmanovic, Stanislav; Khan, Ikhlas A

    2018-02-01

    Twenty-four pure fragrance ingredients have been identified as potential concern for skin sensitization. Several of these compounds are chemically unstable and convert into reactive species upon exposure to air or light. In the present work, a systematic investigation of the correlation between chemical stability and reactivity has been undertaken. The compounds were subjected to forced photodegradation for three months and the chemical changes were studied with GC-MS. At the end of the stability study, two-thirds of the samples were found to be unstable. The generation of chemically reactive species was investigated using the in chemico HTS-DCYA assay. Eleven and fourteen compounds were chemically reactive before and after three months, respectively. A significant increase in reactivity upon degradation was found for isoeugenol, linalool, limonene, lyral, citronellol and geraniol; in the same conditions, the reactivity of hydroxycitronellal decreased. The non-reactive compounds α-isomethyl ionone, benzyl alcohol, amyl cinnamal and farnesol became reactive after photo-oxidative degradation. Overall, forced degradation resulted in four non-reactive fragrance compounds to display in chemico thiol reactivity, while ten out of 24 compounds remained inactive. Chemical degradation does not necessarily occur with generation of reactive species. Non-chemical activation may be involved for the 10 stable unreactive compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Influences of geological parameters to probabilistic assessment of slope stability of embankment

    Science.gov (United States)

    Nguyen, Qui T.; Le, Tuan D.; Konečný, Petr

    2018-04-01

    This article considers influences of geological parameters to slope stability of the embankment in probabilistic analysis using SLOPE/W computational system. Stability of a simple slope is evaluated with and without pore–water pressure on the basis of variation of soil properties. Normal distributions of unit weight, cohesion and internal friction angle are assumed. Monte Carlo simulation technique is employed to perform analysis of critical slip surface. Sensitivity analysis is performed to observe the variation of the geological parameters and their effects on safety factors of the slope stability.

  8. Quality assurance task force, an interagency cooperative approach to assess quality of environmental data

    International Nuclear Information System (INIS)

    Albin, L.M.; Mooney, R.R.; Erickson, J.L.; Conklin, A.W.

    1990-01-01

    In 1985, the Washington State Legislature charged the Department of Social and Health Services' Office of Radiation Protection with reviewing, evaluating and improving environmental monitoring programs within the state. Special emphasis was placed on the Hanford Site in Richland. Government and private organizations involved in monitoring radiation effects on the environment were asked to advise and support the State of Washington. Together, these organizations formed the Environmental Radiation Quality Assurance Task Force for the Pacific Northwest. Data on radiation levels are collected by the various organizations and compared. If findings are not consistent, the Task Force investigates and makes recommendations for long-term solutions. Thus, a system of checks and balances is created, enhancing the credibility of the various monitoring programs. Efficiency in use of resources is increased because overlap and duplication by different monitoring agencies are minimized

  9. Chiral Asymmetric Structures in Aspartic Acid and Valine Crystals Assessed by Atomic Force Microscopy.

    Science.gov (United States)

    Teschke, Omar; Soares, David Mendez

    2016-03-29

    Structures of crystallized deposits formed by the molecular self-assembly of aspartic acid and valine on silicon substrates were imaged by atomic force microscopy. Images of d- and l-aspartic acid crystal surfaces showing extended molecularly flat sheets or regions separated by single molecule thick steps are presented. Distinct orientation surfaces were imaged, which, combined with the single molecule step size, defines the geometry of the crystal. However, single molecule step growth also reveals the crystal chirality, i.e., growth orientations. The imaged ordered lattice of aspartic acid (asp) and valine (val) mostly revealed periodicities corresponding to bulk terminations, but a previously unreported molecular hexagonal lattice configuration was observed for both l-asp and l-val but not for d-asp or d-val. Atomic force microscopy can then be used to identify the different chiral forms of aspartic acid and valine crystals.

  10. Final Environmental Assessment: Military Family Housing Privatization at Keesler Air Force Base, Mississippi

    Science.gov (United States)

    2010-02-01

    a continuous period of at least 10 years {USFWS, 1991). Long term self-sustenance and stability will require a genetically viable population, high...cranes switch some of their preferred items diet to products of upland agriculture including com, seeds, and insects found in farms, pastures , and...open swamp edges, and shallow marshes. FORAGING HABITAT- area for feeding, including upland pasture or cropland, pine savanna, and restorable pine

  11. 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.

  12. General Plan-Based Environmental Impact Analysis Process Environmental Assessment, Altus Air Force Base

    Science.gov (United States)

    2009-11-01

    Level Lmax Maximum Sound Level LOP Letter of Procedure LTM Long-term monitoring MACA Mid-Air Collision Avoidance MFH Military Family Housing mgd...users. Additionally, the Air Force proactively engages in a program of public outreach to aviators, publishing Mid-Air Collision Avoidance ( MACA ...operating under VFR. The MACA contains information on preferred flight tracks, operational characteristics of high-performance military aircraft, and

  13. Final Environmental Assessment for Shared Use Paths (SUP), Eglin Air Force Base, Florida

    Science.gov (United States)

    2011-07-01

    social effects...Use Path (SUP)Environmental AssesmentEglin Air Force Base, Florida "/ "/ "/ "/ "/ "/ "/ "/ "/ "/ "/ Eighth StEglin Blvd Memoria l Dr Griffin Way...StEglin Blvd Memoria l Dr Griffin Way Nomad Way Eglin B lvd FL HW Y 8 5 Chinquapin Dr Perimeter Rd VALPARISO Park Tunn el Taxiw ay PT A rea Com miss

  14. A Capabilities Based Assessment of the United States Air Force Critical Care Air Transport Team

    Science.gov (United States)

    2013-09-01

    MSgt Boyle was notified for a last minute tasking. He was told that the Respiratory Therapist that was originally on alert broke their ankle while...torso and her left foot had been amputated just above the ankle . The third 172 injured person was a Special Forces Soldier. He had been shot in the...damaged area. The USS DENVER is anchored 30 NM due east of the damaged area; whereas USS FRESNO and USS DAYTON have been anchored strategically along

  15. Santa Rosa Island Final Range Environmental Assessment, Revision 1. Eglin Air Force Base, Florida

    Science.gov (United States)

    2012-03-01

    west coast; 3) Dry Tortugas , Florida, Subpopulation; 4) Florida Panhandle Subpopulation occurring at Eglin AFB and the beaches near Panama City; and... Tortugas , florida, Subpopulation, (4) Northwest florida Subpopulation occurring at Eglin Ai r Force Base and the beaches near Panama City; and (5...annually from 1995 and 2005 (FWC/FWRI sea turtle nesting database and unpublished data). A nearly complete census of the Dry Tortugas Subpopulation

  16. Environmental Assessment for Airfield Safety and Drainage Improvements at Patrick Air Force Base, Florida

    Science.gov (United States)

    2011-12-22

    of Cocoa Beach, and covers approximately 2,000 acres bounded by the Atlantic Ocean on the east and the Banana River on the west. The PAFB airfield...significance for greenhouse gas emissions, but the Federal government recognizes the need to reduce energy consumption and shift to renewable and...Historical and Architectural Documentation Reports of Patrick Air Force Base, Cocoa Beach, Florida. U.S. Army Construction Engineering Research

  17. The Air Force Deployment Transition Center: Assessment of Program Structure, Process, and Outcomes

    Science.gov (United States)

    2016-01-01

    lodging and ample recreational activities (tourist waterfront or sightseeing locations). Many allied countries—including Canada , the Netherlands...to the research team because our data use permissions were from the Air Force. Figure 4.1 Sample Accounting for DTC Attendees and Controls NOTE: SSN ...Social Security number. a A match based on having the same SSN and being the first PDHA completed after a date 30 days prior to the DTC attendance

  18. Environmental Assessment for New Veterinary Clinic, Ellsworth Air Force Base, South Dakota

    Science.gov (United States)

    2013-03-01

    The following prehistory and history of Ellsworth AFB has been excerpted from the Ellsworth AFB Integrated Cultural Resource Management Plan (U.S...Air Force, 2011). Prehistoric Period Northern Plains prehistory has been the subject of several published studies and archaeological surveys as...information or research questions related to the prehistory of the immediate Ellsworth AFB area. Historical Period The Black Hills mining boom began

  19. Environmental Assessment for Landfill Drainage Improvements Vandenberg Air Force Base, California

    Science.gov (United States)

    2003-04-07

    became increasingly important, corresponding to development of the tomol (a plank canoe), single-piece shell fishhooks, and harpoons (Glassow 1996...Chumash had a culture that "was as elaborate as that of any hunter-gatherer society on earth" (Moratto 1984: 118). Leadership was hereditary and chiefs...Improvements Vandenberg Air Force Base, California I I I I I I I Erlandson, Jon M., and Kevin Bartoy 1995 Cabrillo, the Chumash, and Old

  20. Assessment of RANS and LES Turbulence Modeling for Buoyancy-Aided/Opposed Forced and Mixed Convection

    Science.gov (United States)

    Clifford, Corey; Kimber, Mark

    2017-11-01

    Over the last 30 years, an industry-wide shift within the nuclear community has led to increased utilization of computational fluid dynamics (CFD) to supplement nuclear reactor safety analyses. One such area that is of particular interest to the nuclear community, specifically to those performing loss-of-flow accident (LOFA) analyses for next-generation very-high temperature reactors (VHTR), is the capacity of current computational models to predict heat transfer across a wide range of buoyancy conditions. In the present investigation, a critical evaluation of Reynolds-averaged Navier-Stokes (RANS) and large-eddy simulation (LES) turbulence modeling techniques is conducted based on CFD validation data collected from the Rotatable Buoyancy Tunnel (RoBuT) at Utah State University. Four different experimental flow conditions are investigated: (1) buoyancy-aided forced convection; (2) buoyancy-opposed forced convection; (3) buoyancy-aided mixed convection; (4) buoyancy-opposed mixed convection. Overall, good agreement is found for both forced convection-dominated scenarios, but an overly-diffusive prediction of the normal Reynolds stress is observed for the RANS-based turbulence models. Low-Reynolds number RANS models perform adequately for mixed convection, while higher-order RANS approaches underestimate the influence of buoyancy on the production of turbulence.

  1. Condition Assessment of PCI Bridge Girder a Result of The Reduction Prestressing Force

    Directory of Open Access Journals (Sweden)

    Suangga Made

    2014-03-01

    Full Text Available PCI bridge girders is known and widely used for many construction e.g.: bridge, wharf, flyover, and other application. PC Bridge girders have two types: Pre - tensioned girders and post - tensioned girders. In pre tensioned girders, prestressing in carried out first then after that the fresh concrete poured. The prestressing process in only carried off after the concrete has sufficient strength. In this study, analysis was conducted for PCI bridge girder with span is 40 meters. Based on the data geometry bridge dimension girder, material girder, and material strands cable, it will be analyzed to calculate the natural frequencies and moment capacity using finite element program (Midas/Civil program. So it can be estimated how much the percentage reduction prestress force on the bridge until PCI bridge structure collapses. From the calculation, it found that the pattern comparison between reduction prestressing force and natural frequency are linear. These results are also similar for natural frequency versus moment capacity.PCI bridge will collapse when the reduction prestreesing force of 45 % to 50 % from the total loss of prestressing.

  2. Assessing the relative importance of parameter and forcing uncertainty and their interactions in conceptual hydrological model simulations

    Science.gov (United States)

    Mockler, E. M.; Chun, K. P.; Sapriza-Azuri, G.; Bruen, M.; Wheater, H. S.

    2016-11-01

    Predictions of river flow dynamics provide vital information for many aspects of water management including water resource planning, climate adaptation, and flood and drought assessments. Many of the subjective choices that modellers make including model and criteria selection can have a significant impact on the magnitude and distribution of the output uncertainty. Hydrological modellers are tasked with understanding and minimising the uncertainty surrounding streamflow predictions before communicating the overall uncertainty to decision makers. Parameter uncertainty in conceptual rainfall-runoff models has been widely investigated, and model structural uncertainty and forcing data have been receiving increasing attention. This study aimed to assess uncertainties in streamflow predictions due to forcing data and the identification of behavioural parameter sets in 31 Irish catchments. By combining stochastic rainfall ensembles and multiple parameter sets for three conceptual rainfall-runoff models, an analysis of variance model was used to decompose the total uncertainty in streamflow simulations into contributions from (i) forcing data, (ii) identification of model parameters and (iii) interactions between the two. The analysis illustrates that, for our subjective choices, hydrological model selection had a greater contribution to overall uncertainty, while performance criteria selection influenced the relative intra-annual uncertainties in streamflow predictions. Uncertainties in streamflow predictions due to the method of determining parameters were relatively lower for wetter catchments, and more evenly distributed throughout the year when the Nash-Sutcliffe Efficiency of logarithmic values of flow (lnNSE) was the evaluation criterion.

  3. Assessment of the Short-Term Radiometric Stability between Terra MODIS and Landsat 7 ETM+ Sensors

    Science.gov (United States)

    Choi, Taeyoung; Xiong, Xiaxiong; Chander, G.; Angal, Amit

    2009-01-01

    ) was included in the path of this continuous orbit, which served as a verification point between the shortterm and the long-term trending results from previous studies. This work focuses on monitoring the short-term on-orbit stability of MODIS and the ETM+ RSB. It also provides an assessment of the absolute calibration differences between the two sensors over their wide dynamic ranges.

  4. Small disturbance voltage stability assessment of power systems by modal analysis and dynamic simulation

    International Nuclear Information System (INIS)

    Amjady, Nima; Ansari, Mohammad Reza

    2008-01-01

    The introduction of liberalized electricity markets in many countries has resulted in more highly stressed power systems. On the other hand, operating points of a power system are acceptable in the feasible region, which is surrounded by the borders of different stabilities. Power system instability is critical for all participants of the electricity market. Determination of different stability margins can result in the optimum utilization of power system with minimum risk. This paper focuses on the small disturbance voltage stability, which is an important subset of the power system global stability. This kind of voltage stability is usually evaluated by static analysis tools such as continuation power flow, while it essentially has dynamic nature. Besides, a combination of linear and nonlinear analysis tools is required to correctly analyze it. In this paper, a hybrid evaluation method composed of static, dynamic, linear, and nonlinear analysis tools is proposed for this purpose. Effect of load scenario, generation pattern, branch and generator contingency on the small disturbance voltage stability are evaluated by the hybrid method. The test results are given for New England and IEEE68 bus test systems. (author)

  5. Primary stability and self-tapping blades: biomechanical assessment of dental implants in medium-density bone.

    Science.gov (United States)

    Kim, Yung-Soo; Lim, Young-Jun

    2011-10-01

    The aim of this biomechanical study was to assess the influence of self-tapping blades in terms of primary implant stability between implants with self-tapping blades and implants without self-tapping blades using five different analytic methods, especially in medium-density bone. Two different types of dental implants (4 × 10 mm) were tested: self-tapping and non-self-tapping. The fixture design including thread profiles was exactly the same between the two groups; the only difference was the presence of cutting blades on one half of the apical portion of the implant body. Solid rigid polyurethane blocks with corresponding densities were selected to simulate medium-density bone. Five mechanical assessments (insertion torque, resonance frequency analysis [RFA], reverse torque, pull-out and push in test) were performed for primary stability. Implants without self-tapping blades showed significantly higher values (P0.05). The outcomes of the present study indicate that the implant body design without self-tapping blades has a good primary stability compared with that with self-tapping blades in medium-density bone. Considering the RFA, a distinct layer of cortical bone on marginal bone will yield implant stability quotient values similar to those in medium-bone density when implants have the same diameter. © 2011 John Wiley & Sons A/S.

  6. Wearable sensor use for assessing standing balance and walking stability in people with Parkinson's disease: a systematic review.

    Science.gov (United States)

    Hubble, Ryan P; Naughton, Geraldine A; Silburn, Peter A; Cole, Michael H

    2015-01-01

    Postural instability and gait disability threaten the independence and well-being of people with Parkinson's disease and increase the risk of falls and fall-related injuries. Prospective research has shown that commonly-used clinical assessments of balance and walking lack the sensitivity to accurately and consistently identify those people with Parkinson's disease who are at a higher risk of falling. Wearable sensors provide a portable and affordable alternative for researchers and clinicians who are seeking to objectively assess movements and falls risk in the clinical setting. However, no consensus currently exists on the optimal placements for sensors and the best outcome measures to use for assessing standing balance and walking stability in Parkinson's disease patients. Hence, this systematic review aimed to examine the available literature to establish the best sensor types, locations and outcomes to assess standing balance and walking stability in this population. Papers listed in three electronic databases were searched by title and abstract to identify articles measuring standing balance or walking stability with any kind of wearable sensor among adults diagnosed with PD. To be eligible for inclusion, papers were required to be full-text articles published in English between January 1994 and December 2014 that assessed measures of standing balance or walking stability with wearable sensors in people with PD. Articles were excluded if they; i) did not use any form of wearable sensor to measure variables associated with standing balance or walking stability; ii) did not include a control group or control condition; iii) were an abstract and/or included in the proceedings of a conference; or iv) were a review article or case study. The targeted search of the three electronic databases identified 340 articles that were potentially eligible for inclusion, but following title, abstract and full-text review only 26 articles were deemed to meet the inclusion

  7. Wearable Sensor Use for Assessing Standing Balance and Walking Stability in People with Parkinson’s Disease: A Systematic Review

    Science.gov (United States)

    Hubble, Ryan P.; Naughton, Geraldine A.; Silburn, Peter A.; Cole, Michael H.

    2015-01-01

    Background Postural instability and gait disability threaten the independence and well-being of people with Parkinson’s disease and increase the risk of falls and fall-related injuries. Prospective research has shown that commonly-used clinical assessments of balance and walking lack the sensitivity to accurately and consistently identify those people with Parkinson’s disease who are at a higher risk of falling. Wearable sensors provide a portable and affordable alternative for researchers and clinicians who are seeking to objectively assess movements and falls risk in the clinical setting. However, no consensus currently exists on the optimal placements for sensors and the best outcome measures to use for assessing standing balance and walking stability in Parkinson’s disease patients. Hence, this systematic review aimed to examine the available literature to establish the best sensor types, locations and outcomes to assess standing balance and walking stability in this population. Methods Papers listed in three electronic databases were searched by title and abstract to identify articles measuring standing balance or walking stability with any kind of wearable sensor among adults diagnosed with PD. To be eligible for inclusion, papers were required to be full-text articles published in English between January 1994 and December 2014 that assessed measures of standing balance or walking stability with wearable sensors in people with PD. Articles were excluded if they; i) did not use any form of wearable sensor to measure variables associated with standing balance or walking stability; ii) did not include a control group or control condition; iii) were an abstract and/or included in the proceedings of a conference; or iv) were a review article or case study. The targeted search of the three electronic databases identified 340 articles that were potentially eligible for inclusion, but following title, abstract and full-text review only 26 articles were deemed

  8. Wearable sensor use for assessing standing balance and walking stability in people with Parkinson's disease: a systematic review.

    Directory of Open Access Journals (Sweden)

    Ryan P Hubble

    Full Text Available Postural instability and gait disability threaten the independence and well-being of people with Parkinson's disease and increase the risk of falls and fall-related injuries. Prospective research has shown that commonly-used clinical assessments of balance and walking lack the sensitivity to accurately and consistently identify those people with Parkinson's disease who are at a higher risk of falling. Wearable sensors provide a portable and affordable alternative for researchers and clinicians who are seeking to objectively assess movements and falls risk in the clinical setting. However, no consensus currently exists on the optimal placements for sensors and the best outcome measures to use for assessing standing balance and walking stability in Parkinson's disease patients. Hence, this systematic review aimed to examine the available literature to establish the best sensor types, locations and outcomes to assess standing balance and walking stability in this population.Papers listed in three electronic databases were searched by title and abstract to identify articles measuring standing balance or walking stability with any kind of wearable sensor among adults diagnosed with PD. To be eligible for inclusion, papers were required to be full-text articles published in English between January 1994 and December 2014 that assessed measures of standing balance or walking stability with wearable sensors in people with PD. Articles were excluded if they; i did not use any form of wearable sensor to measure variables associated with standing balance or walking stability; ii did not include a control group or control condition; iii were an abstract and/or included in the proceedings of a conference; or iv were a review article or case study. The targeted search of the three electronic databases identified 340 articles that were potentially eligible for inclusion, but following title, abstract and full-text review only 26 articles were deemed to meet the

  9. AMI Go Home - Assessing the Realignment of U.S. Army Forces in Europe

    Science.gov (United States)

    2005-03-18

    a major U.S. investment.37 According to Stuart Drury of the Joint Chiefs of Staff, deploying would be much more difficult from Eastern Europe...35 Ibid, xvi. 36 Ibid,12. 37 Ibid, 29. 38 Stuart P. Drury , “The Argument Against Relocating U.S. Forces in Europe,” National Defense University...Europe in the 21st Century,” Parameters (Autumn 2004): 61. 53 Colin Powell, “A Strategy of Partnership,” Foreign Affairs (Jan/Feb 2004): 22. 54 Michael

  10. Mobile Detection Assessment and Response Systems (MDARS): A Force Protection, Physical Security Operational Success

    National Research Council Canada - National Science Library

    Shoop, Brian; Johnston, Michael; Goehring, Richard; Moneyhun, Jon; Skibba, Brian

    2006-01-01

    ...). MDARS capabilities include semi-autonomous navigation, obstacle avoidance, motion detection, day and night imagers, radio frequency tag inventory/barrier assessment and audio challenge and response...

  11. Assessment of rock mechanical properties and seismic slope stability in variably weathered layered basalts

    Science.gov (United States)

    Greenwood, William; Clark, Marin; Zekkos, Dimitrios; Von Voigtlander, Jennifer; Bateman, Julie; Lowe, Katherine; Hirose, Mitsuhito; Anderson, Suzanne; Anderson, Robert; Lynch, Jerome

    2016-04-01

    A field and laboratory experimental study was conducted to assess the influence of weathering on the mechanical properties of basalts in the region of the Kohala volcano on the island of Hawaii. Through the systematic characterization of the weathering profiles developed in different precipitation regimes, we aim to explain the regional pattern of stability of slopes in layered basalts that were observed during the 2006 Mw 6.7 Kiholo Bay earthquake. While deeper weathering profiles on the wet side of the island might be expected to promote more and larger landslides, the distribution of landslides during the Kiholo Bay earthquake did not follow this anticipated trend. Landslide frequency (defined as number of landslides divided by total area) was similar on the steepest slopes (> 50-60) for both the dry and the wet side of the study area suggesting relatively strong ground materials irrespective of weathering. The study location is ideally suited to investigate the role of precipitation, and more broadly of climate, on the mechanical properties of the local rock units because the presence of the Kohala volcano produces a significant precipitation gradient on what are essentially identical basaltic flows. Mean annual precipitation (MAP) varies by more than an order of magnitude, from 200 mm/year on the western side of the volcano to 4000 mm/year in the eastern side. We will present results of measured shear wave velocities using a seismic surface wave methodology. These results were paired with laboratory testing on selected basalt specimens that document the sample-scale shear wave velocity and unconfined compressive strength of the basaltic rocks. Shear wave velocity and unconfined strength of the rocks are correlated and are both significantly lower in weathered rocks near the ground surface than at depth. This weathering-related reduction in shear wave velocity extends to greater depths in areas of high precipitation compared to areas of lower precipitation

  12. Long Term Behaviour of 14C and Stability Assessments of Graphite Under Repository Conditions

    International Nuclear Information System (INIS)

    Jones, Abbie N.; McDermott, Lorraine; Worth, Robert; Hagos, Bereket; Black, Greg; Marsden, Barry J

    2016-01-01

    The key objectives of the University of Manchester’s nuclear graphite research within the CRP are to provide analysis on the long term behaviour and stability assessments of irradiated graphite waste. The research will concentrate on isotopic 14 C mobility under repository environments. This also requires an understanding the long-term behaviour of the final waste form under repository conditions. Procedures to evaluate the long term leaching properties of radionuclides from irradiated graphite waste has been developed by combining ANSI 16.1 (USA) and NEN 7345 (Netherlands) standardised diffusion leaching techniques. The ANSI 16.1 standard has been followed to acquire the leachates and to determine the leach rate and diffusion coefficient. The NEN 7345 standard technique has been used to determine the diffusion mechanism of radionuclides. The investigation employs simulated Drigg groundwater as a leachant using semi-dynamic technique for the production of leachate specimens. Analysis of 3 H and 14 C activity release from Magnox graphite was measured using liquid scintillating counting. Preliminary results show that there is an initial high release of activity and decreases when the leaching period increases. This may be due to the depletion of contaminants that were initially bound by the internal pore networks and the free surface. During the leaching test approximately 275.33 ± 18.20 Bq of 3 H and 106.26 ± 7.01 Bq of 14 C was released into the leachant within 91 days. The work reported herein contributed several key findings to the international work on graphite leaching to offer guidance leading toward obtaining leaching data in the future: (a) the effective diffusion coefficient for 14 C from graphite waste has been determined. The diffusion process for 14 C has two stages resulting two different values of diffusion coefficient, i.e., for the fast and slow components; (b) the controlling leaching mechanism for 3 H radionuclide from graphite is shown to be

  13. Assessment of a wearable force- and electromyography device and comparison of the related signals for myocontrol

    Directory of Open Access Journals (Sweden)

    Mathilde Connan

    2016-11-01

    Full Text Available In the frame of assistive robotics, multi-finger prosthetic hand/wrists have recently appeared,offering an increasing level of dexterity; however, in practice their control is limited to a few handgrips and still unreliable, with the effect that pattern recognition has not yet appeared in the clinicalenvironment. According to the scientific community, one of the keys to improve the situation ismulti-modal sensing, i.e., using diverse sensor modalities to interpret the subject’s intent andimprove the reliability and safety of the control system in daily life activities. In this work, wefirst describe and test a novel wireless, wearable force- and electromyography device; throughan experiment conducted on ten intact subjects, we then compare the obtained signals bothqualitatively and quantitatively, highlighting their advantages and disadvantages. Our resultsindicate that force-myography yields signals which are more stable across time during whenevera pattern is held, than those obtained by electromyography. We speculate that fusion of the twomodalities might be advantageous to improve the reliability of myocontrol in the near future.

  14. Assessment of student knowledge of the weak and strong nuclear forces

    Science.gov (United States)

    Shakya, Pramila

    The purpose of this study was to determine if the use of active-learning activities to teach weak force and strong force to students enrolled in various courses at The University of Southern Mississippi, Hattiesburg campus and Gulf Park campus at different class times would increase their knowledge. There were eighty-six students that took part in this study. The study was conducted in the lab classes of an introductory astronomy survey course (AST 111), an introductory algebra-based physics course (PHY 112), and an introductory calculus-based physics course (PHY 202) during fall semester, 2014. Each class was randomly assigned as active-learning or direct instruction. A pretest followed by lecture was administered to all groups. The active-learning group performed four activities whereas the direct group watched a video irrelevant to the lesson. At the end of the lesson, the same post-test was given to all groups. Various statistical methods were used to analyze the differences in mean pretest and posttest scores. Overall, results show that the mean posttest scores were higher than the mean pretest scores. Findings support the use of active-learning activities work to the small number of students or the equal number of students in a group. The mean posttest scores of the direct instruction classes were higher than those of the active-learning groups.

  15. Assessment of implant stability during various stages of healing placed immediately following extraction in an overdenture situation

    OpenAIRE

    Ashwin Thomas Koshy; T Aby Mathew; Nicholas Mathew; Angel Mary Joseph

    2017-01-01

    To assess the implant stability during different stages of healing in an immediate loaded implant soon after extraction. A 73-year-old female came with a chief complaint of bad smell and irritation in her lower front gum region. On examination, she was found to be completely edentulous in the maxillary arch and partially edentulous in the mandibular arch with only the canines present bilaterally. The posterior mandibular ridge was severely resorbed and hence could not be treated with a conven...

  16. Taxonomic Structure and Stability of the Bacterial Community in Belgian Sourdough Ecosystems as Assessed by Culture and Population Fingerprinting▿ †

    OpenAIRE

    Scheirlinck, Ilse; Van der Meulen, Roel; Van Schoor, Ann; Vancanneyt, Marc; De Vuyst, Luc; Vandamme, Peter; Huys, Geert

    2008-01-01

    A total of 39 traditional sourdoughs were sampled at 11 bakeries located throughout Belgium which were visited twice with a 1-year interval. The taxonomic structure and stability of the bacterial communities occurring in these traditional sourdoughs were assessed using both culture-dependent and culture-independent methods. A total of 1,194 potential lactic acid bacterium (LAB) isolates were tentatively grouped and identified by repetitive element sequence-based PCR, followed by sequence-base...

  17. Preliminary Assessment of Potential Avian Interactions at Four Proposed Wind Energy Facilities on Vandenberg Air Force Base, California

    Energy Technology Data Exchange (ETDEWEB)

    2004-08-01

    The United States Air Force (USAF) is investigating whether to install wind turbines to provide a supplemental source of electricity at Vandenberg Air Force Base (VAFB) near Lompoc, California. As part of that investigation, VAFB sought assistance from the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) to provide a preliminary characterization of the potential risk to wildlife resources (mainly birds and bats) from wind turbine installations. With wind power development expanding throughout North America and Europe, concerns have surfaced over the number of bird fatalities associated with wind turbines. Guidelines developed for the wind industry by the National Wind Coordinating Committee (NWCC) recommend assessing potential impacts to birds, bats, and other potentially sensitive resources before construction. The primary purpose of an assessment is to identify potential conflicts with sensitive resources, to assist developers with identifying their permitting needs, and to develop strategies to avoid impacts or to mitigate their effects. This report provides a preliminary (Phase I) biological assessment of potential impacts to birds and bats that might result from construction and operation of the proposed wind energy facilities on VAFB.

  18. On-line transient stability assessment of large-scale power systems by using ball vector machines

    International Nuclear Information System (INIS)

    Mohammadi, M.; Gharehpetian, G.B.

    2010-01-01

    In this paper ball vector machine (BVM) has been used for on-line transient stability assessment of large-scale power systems. To classify the system transient security status, a BVM has been trained for all contingencies. The proposed BVM based security assessment algorithm has very small training time and space in comparison with artificial neural networks (ANN), support vector machines (SVM) and other machine learning based algorithms. In addition, the proposed algorithm has less support vectors (SV) and therefore is faster than existing algorithms for on-line applications. One of the main points, to apply a machine learning method is feature selection. In this paper, a new Decision Tree (DT) based feature selection technique has been presented. The proposed BVM based algorithm has been applied to New England 39-bus power system. The simulation results show the effectiveness and the stability of the proposed method for on-line transient stability assessment procedure of large-scale power system. The proposed feature selection algorithm has been compared with different feature selection algorithms. The simulation results demonstrate the effectiveness of the proposed feature algorithm.

  19. The Amalgamation of SVR and ANFIS Models with Synchronized Phasor Measurements for On-Line Voltage Stability Assessment

    Directory of Open Access Journals (Sweden)

    Mohammed Amroune

    2017-10-01

    Full Text Available This paper presents the application of support vector regression (SVR and adaptive neuro-fuzzy inference system (ANFIS models that are amalgamated with synchronized phasor measurements for on-line voltage stability assessment. As the performance of SVR model extremely depends on the good selection of its parameters, the recently developed ant lion optimizer (ALO is adapted to seek for the SVR’s optimal parameters. In particular, the input vector of ALO-SVR and ANFIS soft computing models is provided in the form of voltage magnitudes provided by the phasor measurement units (PMUs. In order to investigate the effectiveness of ALO-SVR and ANFIS models towards performing the on-line voltage stability assessment, in-depth analyses on the results have been carried out on the IEEE 30-bus and IEEE 118-bus test systems considering different topologies and operating conditions. Two statistical performance criteria of root mean square error (RMSE and correlation coefficient (R were considered as metrics to further assess both of the modeling performances in contrast with the power flow equations. The results have demonstrated that the ALO-SVR model is able to predict the voltage stability margin with greater accuracy compared to the ANFIS model.

  20. Assessment of additional impacts to environment during Ukryttya object stabilization works

    International Nuclear Information System (INIS)

    Klyuchnikov, A.A.; Shcherbin, V.N.; Rud'ko, V.M.; Batij, V.G.; Sizov, A.A.; Khavrus', V.G.

    2004-01-01

    Estimates of impact levels onto environment were made when implementing stabilization works of unstable building structures of Ukryttya object. The impact were evaluated to air water medium, as well to ground cover, social and technogenic environments. It was demonstrated, that impact levels to above environmental components under normal conditions of work implementation are negligible, and radioactive substance amount, which will penetrate into the environment, will make parts of percents to existing contamination of exclusion zone area. Estimates are also made of accident impacts onto environment, whose origination is probable during the stabilization works of Ukryttya object

  1. Stabilizing greenhouse gas emissions: Assessing the intergenerational costs and benefits of the Kyoto Protocol

    International Nuclear Information System (INIS)

    Kavuncu, Y. Okan; Knabb, Shawn D.

    2005-01-01

    The costs and benefits current and future generations incur as the result of climate change or an environmental control policy are often confounded with other objectives, such as, generational discounting or optimal policy design. This paper uses a consumption equivalent measure to simulate the loss or gain of consumption independent of these confounding objectives. The findings suggest that the costs associated with an emissions stabilization program are relatively large for current generations and continue to increase over the next 100 years. The first generation to actually benefit from the stabilization program is born early during the 24th century

  2. Stability model and risk assessment for the Montescaglioso Landslide (Southern Italy)

    Science.gov (United States)

    Amanti, Marco; Chiessi, Vittorio; Guarino, Paolo Maria; Spizzichino, Daniele; Troccoli, Alessandro; Vizzini, Giorgio

    2015-04-01

    In this paper, we present the final results of a landslide risk assessment evaluation implemented for the recent Montescaglioso landslide emergency occurred on 3rd December 2013 when a large and rapid slope failure, triggered by prolonged and intense rainfall, affected a big portion of the SW slope of the village. The slope failure damaged a main road, private homes and commercial buildings. The Montescaglioso village (Basilicata Region, Italy) is located on the top of a conglomerate hill overlying a gentle slope constituted by Plio-Pleistocene clays. The area has been affected since ancient time by different landslide typologies and mechanism, as determined by a direct geomorphological survey and from mapping and available technical literature. Phenomena such as rock-falls and rock lateral spreading in the upper part of the hill, and rotational/translational slides and earth flows can be recognized in the area. Landslides are mainly promoted by the geological and structural setting of the area as well as by very low mechanical characteristics of sediments outcropping in the area. After the emergency phase, a detailed program of field survey and laboratory campaign has been implemented during the last year. A detailed topographical analysis has been developed by using the LIDAR survey in order to define morphometric conditions and geometry modifications of the slope affected by the landslide. Based on the studies carried out in the area, the research has been aimed to assessing the stability conditions (residual landslide risk) of the SW slope of the hill trough an extended geological, geomorphological and geotechnical campaign linked with numerical study of present instability mechanism. The geological and geotechnical model of the slope has been defined trough the analysis of the past and recent logs obtained from several boreholes and also through the results of many mechanical test performed on samples taken in the area. The numerical study has been carried out

  3. Assessment of the effect of prolonged forced swimming on CD-1 mice sperm morphology with and without antioxidant supplementation.

    Science.gov (United States)

    Rodriguez, I; Diaz, A; Vaamonde, D

    2016-04-01

    As physical exercise has been shown to negatively affect sperm morphology, this study was undertaken to assess the effect of a 3-min forced swimming protocol during 50 days, with and without administration of antioxidants [N-acetylcysteine (NAC) and trans-resveratrol], on sperm morphology in CD-1 mice. Forty-four 13-week-old CD-1 mice were randomly allocated to four different groups: mice not submitted to exercise, control group (CG), mice submitted to swimming without administration of antioxidants (EX), mice submitted to swimming that received trans-resveratrol supplementation [exercise group (EX)+Resv] and mice submitted to swimming exercise that received NAC supplementation (EX+NAC). The EX showed 30.5% of spermatozoa with normal morphology, showing significant differences with regard to the CG, which showed 58.5%. The groups receiving antioxidant supplements showed significantly higher percentages of spermatozoa with normal morphology in comparison with the EX group (EX+Resv: 64.1%, EX+NAC: 48.2%). The imposed model of forced swimming caused alterations in sperm morphology. The antioxidants employed seem to be suitable antioxidants for avoiding exercise-associated sperm morphology anomalies in prolonged forced swimming exercise. Trans-resveratrol has proven to be more efficient for this purpose. © 2015 Blackwell Verlag GmbH.

  4. Assessing human resources for health: what can be learned from labour force surveys?

    Directory of Open Access Journals (Sweden)

    Dal Poz Mario R

    2003-07-01

    Full Text Available Abstract Background Human resources are an essential element of a health system's inputs, and yet there is a huge disparity among countries in how human resource policies and strategies are developed and implemented. The analysis of the impacts of services on population health and well-being attracts more interest than analysis of the situation of the workforce in this area. This article presents an international comparison of the health workforce in terms of skill mix, sociodemographics and other labour force characteristics, in order to establish an evidence base for monitoring and evaluation of human resources for health. Methods Profiles of the health workforce are drawn for 18 countries with developed market and transitional economies, using data from labour force and income surveys compiled by the Luxembourg Income Study between 1989 and 1997. Further descriptive analyses of the health workforce are conducted for selected countries for which more detailed occupational information was available. Results Considerable cross-national variations were observed in terms of the share of the health workforce in the total labour market, with little discernible pattern by geographical region or type of economy. Increases in the share were found among most countries for which time-trend data were available. Large gender imbalances were often seen in terms of occupational distribution and earnings. In some cases, health professionals, especially physicians, were overrepresented among the foreign-born compared to the total labour force. Conclusions While differences across countries in the profile of the health workforce can be linked to the history and role of the health sector, at the same time some common patterns emerge, notably a growing trend of health occupations in the labour market. The evidence also suggests that gender inequity in the workforce remains an important shortcoming of many health systems. Certain unexpected patterns of

  5. Does the Future Engineer Force Transition Engineer Units between Offensive and Stability Operations in Ways That Achieve Responsiveness, Versatility, Agility, Effectiveness, and Efficiency?

    National Research Council Canada - National Science Library

    London, David T

    2005-01-01

    .... The main question is as follows: Does the FEF transition engineer units between offensive and stability operations in ways that achieve responsiveness, versatility, agility, effectiveness, and efficiency...

  6. Assessment of stability of trace elements in two natural matrix environmental standard reference materials. NIST-SRM 1547 Peach leaves and NIST-SRM 1566a Oyster Tissue

    International Nuclear Information System (INIS)

    Mackey, E.A.; Spatz, R.O.

    2009-01-01

    The NIST program for environmental Standard Reference Materials (SRM) includes materials covering a range of matrices, mass fraction values and analytes. For many SRMs, mass fraction data are accumulated, incidentally, over time, as these are used routinely for quality assurance purposes. Although these are not formal stability studies, data generated may be useful in assessing stability. To evaluate the potential for assessing material stability from incidental use of SRMs, results of neutron activation analysis performed from 1992 through 2008 were compiled for SRM 1547 Peach Leaves and SRM 1566a Oyster Tissue. Results indicate that incidental use of SRMs yields useful information on SRM stability. (author)

  7. Environmental Assessment Improvements to Silver Flag Training Area at Tyndall Air Force Base, Florida

    Science.gov (United States)

    2013-08-02

    Acronyms and Abbreviations ACC  Air Combat Command  ACM  asbestos‐containing  materials   AICUZ  Air Installation Compatible Use Zone  AFB   Air Force...wet flatwoods, ditches, seepage  slopes, cypress swamps  White‐flowered wild  petunia   Ruellia noctiflora    E  G2/S2  Wet prairies, wet flatwoods...Tyndall AFB ICRMP are required to be implemented in the  event that cultural  materials  are discovered during construction activities. SOP 4, All

  8. Marine Hydrokinetic Resource Assessment for Domestic Army, Air Force, and Coast Guard Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Robichaud, Robi J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Ingram, Michael [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2018-04-24

    NREL/DOE undertook a study for the US Army, Coast Guard and Air Force to investigate the potential for marine hydrokinetic (MHK) devices to meet the energy load at coastal bases in the future as MHK technology evolves. A wide range of data from tidal and wave, environmental, shipping, etc. databases were used to screen the DOD bases. A series of scoring algorithms were developed to facilitate site review to lead to eventual down select for more detailed, site specific bathymetric tidal resource evaluation. The Army's Camp Edwards, MA and the Coast Guard's Training Center Cape May, NJ (TRACEN Cape May) were selected and the Georgia Institute of Technology performed the analyses. An NREL/DOE MHK team visited the bases to further discuss with the base personnel MHK technology's potential for providing power to the bases in the future and frame the potential impact to existing power systems.

  9. Application of quality by design concept to develop a dual gradient elution stability-indicating method for cloxacillin forced degradation studies using combined mixture-process variable models.

    Science.gov (United States)

    Zhang, Xia; Hu, Changqin

    2017-09-08

    Penicillins are typical of complex ionic samples which likely contain large number of degradation-related impurities (DRIs) with different polarities and charge properties. It is often a challenge to develop selective and robust high performance liquid chromatography (HPLC) methods for the efficient separation of all DRIs. In this study, an analytical quality by design (AQbD) approach was proposed for stability-indicating method development of cloxacillin. The structures, retention and UV characteristics rules of penicillins and their impurities were summarized and served as useful prior knowledge. Through quality risk assessment and screen design, 3 critical process parameters (CPPs) were defined, including 2 mixture variables (MVs) and 1 process variable (PV). A combined mixture-process variable (MPV) design was conducted to evaluate the 3 CPPs simultaneously and a response surface methodology (RSM) was used to achieve the optimal experiment parameters. A dual gradient elution was performed to change buffer pH, mobile-phase type and strength simultaneously. The design spaces (DSs) was evaluated using Monte Carlo simulation to give their possibility of meeting the specifications of CQAs. A Plackett-Burman design was performed to test the robustness around the working points and to decide the normal operating ranges (NORs). Finally, validation was performed following International Conference on Harmonisation (ICH) guidelines. To our knowledge, this is the first study of using MPV design and dual gradient elution to develop HPLC methods and improve separations for complex ionic samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Mobile Detection Assessment and Response Systems (MDARS): A Force Protection, Physical Security Operational Success

    National Research Council Canada - National Science Library

    Shoop, Brian; Johnston, Michael; Goehring, Richard; Moneyhun, Jon; Skibba, Brian

    2006-01-01

    ... & barrier assessment payloads. Its functions include surveillance, security, early warning, incident first response and product and barrier status primarily focused on a depot/munitions security mission at structured/semi-structured facilities...

  11. Forcing of global ocean models using an atmospheric boundary layer model: assessing consequences for the simulation of the AMOC

    Science.gov (United States)

    Abel, Rafael; Boening, Claus

    2015-04-01

    Current practice in the atmospheric forcing of ocean model simulations can lead to unphysical behaviours. The problem lies in the bulk formulation of the turbulent air-sea fluxes in conjunction with a prescribed, and unresponsive, atmospheric state as given, e.g., by reanalysis products. This forcing formulation corresponds to assuming an atmosphere with infinite heat capacity, and effectively damps SST anomalies even on basin scales. It thus curtails an important negative feedback between meridional ocean heat transport and SST in the North Atlantic, rendering simulations of the AMOC in such models excessively sensitive to details in the freshwater fluxes. As a consequence, such simulations are known for spurious drift behaviors which can only partially controlled by introducing some (and sometimes strong) unphysical restoring of sea surface salinity. There have been several suggestions during the last 20 years for at least partially alleviating the problem by including some simplified model of the atmospheric boundary layer (AML) which allows a feedback of SST anomalies on the near-surface air temperature and humidity needed to calculate the surface fluxes. We here present simulations with a simple, only thermally active AML formulation (based on the 'CheapAML' proposed by Deremble et al., 2013) implemented in a global model configuration based on NEMO (ORCA05). In a suite of experiments building on the CORE-bulk forcing methodology, we examine some general features of the AML-solutions (in which only the winds are prescribed) in comparison to solutions with a prescribed atmosperic state. The focus is on the North Atlantic, where we find that the adaptation of the atmospheric temperature the simulated ocean state can lead to strong local modifications in the surface heat fluxes in frontal regions (e.g., the 'Northwest Corner'). We particularly assess the potential of the AML-forcing concept for obtaining AMOC-simulations with reduced spurious drift, without

  12. Is there a role for oligosaccharides in seed longevity? An assessment of intracellular glass stability

    NARCIS (Netherlands)

    Buitink, J.; Hemminga, M.A.; Hoekstra, F.A.

    2000-01-01

    We examined whether oligosaccharides extend seed longevity by increasing the intracellular glass stability. For that purpose, we used a spin probe technique to measure the molecular mobility and glass transition temperature of the cytoplasm of impatiens (Impatiens walleriana) and bell pepper

  13. A Project Assessment of Stabilizing System of WT Generation using Rechargeable Battery

    Science.gov (United States)

    Kojima, Yasuhiro; Takano, Tomihiro; Tanikawa, Ryoichi; Takagi, Tetsuro; Hirooka, Koutaro; Kumagai, Sadatoshi

    The expansion of the renewable energy introduction is examined as measures for controlling global warming. Wind power generation is expected as effective power resource, but the negative impact from the difficulty of an unstable output is concerned. In recent years, WT generation with contract of cut-of with shorting adjusting power and with rechargeable battery for stabilizing control are examined, but the introduction has not been accelerated yet because there is an influence in WT generation entrepreneur's business. In this paper, we make a brief summary of relation between the fluctuation of wind power generation and stability of electric power operation, and two types of approach; cut-off contract and stabilization using rechargeable battery. For the stabilization using battery, there are two methods, one is reduction control and the other is constant control. We propose a new control method for constant control based on profit optimization considering WT generation forecast and its risk of deviation. We also propose the estimation method for the .limitation of battery installation. Simulation results show the efficiency of our proposed methods.

  14. Temporal Stability of Strength-Based Assessments: Test-Retest Reliability of Student and Teacher Reports

    Science.gov (United States)

    Romer, Natalie; Merrell, Kenneth W.

    2013-01-01

    This study focused on evaluating the temporal stability of self-reported and teacher-reported perceptions of students' social and emotional skills and assets. We used a test-retest reliability procedure over repeated administrations of the child, adolescent, and teacher versions of the "Social-Emotional Assets and Resilience Scales".…

  15. Assessment of structural stability of a degraded sandy clay loam soil ...

    African Journals Online (AJOL)

    The effects of bare, two legumes and four grasses cover treatments on the structural stability of a sandy clay loam Ultisol were studied within a two year period. The experiment was of a randomised complete block design with seven treatments. The legume treatments were Centrosema pubescens (Ce) and Pueraria ...

  16. Stochastic stability assessment of a semi-free piston engine generator concept

    Science.gov (United States)

    Kigezi, T. N.; Gonzalez Anaya, J. A.; Dunne, J. F.

    2016-09-01

    Small engines, as power generators with low-noise and vibration characteristics, are needed in two niche application areas: as electric vehicle range extenders and as domestic micro Combined Heat and Power systems. A recent semi-free piston design known as the AMOCATIC generator fully meets this requirement. The engine potentially allows for high energy conversion efficiencies at resonance derived from having a mass and spring assembly. As with free-piston engines in general, stability and control of piston motion has been cited as the prime challenge limiting the technology's widespread application. Using physical principles, we derive in this paper two important results: an energy balance criterion and a related general stability criterion for a semi-free piston engine. Control is achieved by systematically designing a Proportional Integral (PI) controller using a control-oriented engine model for which a specific stability condition is stated. All results are presented in closed form throughout the paper. Simulation results under stochastic pressure conditions show that the proposed energy balance, stability criterion, and PI controller, operate as predicted to yield stable engine operation at fixed compression ratio.

  17. Stability of Early Risk Assessment for Autism Spectrum Disorder in Preterm Infants

    Science.gov (United States)

    Yaari, Maya; Yitzhak, Neta; Harel, Ayelet; Friedlander, Edwa; Bar-Oz, Benjamin; Eventov-Friedman, Smadar; Mankuta, David; Gamliel, Ifat; Yirmiya, Nurit

    2016-01-01

    Stability and change in early autism spectrum disorder risk were examined in a cohort of 99 preterm infants (?34 weeks of gestation) using the Autism Observation Scale for Infants at 8 and 12 months and the Autism Diagnostic Observation Schedule--Toddler Module at 18 months. A total of 21 infants were identified at risk by the Autism Observation…

  18. Stochastic stability assessment of a semi-free piston engine generator concept

    International Nuclear Information System (INIS)

    Kigezi, T N; Anaya, J A Gonzalez; Dunne, J F

    2016-01-01

    Small engines, as power generators with low-noise and vibration characteristics, are needed in two niche application areas: as electric vehicle range extenders and as domestic micro Combined Heat and Power systems. A recent semi-free piston design known as the AMOCATIC generator fully meets this requirement. The engine potentially allows for high energy conversion efficiencies at resonance derived from having a mass and spring assembly. As with free-piston engines in general, stability and control of piston motion has been cited as the prime challenge limiting the technology's widespread application. Using physical principles, we derive in this paper two important results: an energy balance criterion and a related general stability criterion for a semi-free piston engine. Control is achieved by systematically designing a Proportional Integral (PI) controller using a control-oriented engine model for which a specific stability condition is stated. All results are presented in closed form throughout the paper. Simulation results under stochastic pressure conditions show that the proposed energy balance, stability criterion, and PI controller, operate as predicted to yield stable engine operation at fixed compression ratio. (paper)

  19. Assessment of factors and conditions influencing bank stability of future lakes

    Czech Academy of Sciences Publication Activity Database

    Spanilá, Tamara; Kudrna, Z.; John, V.; Hartvich, Filip; Chour, V.

    2006-01-01

    Roč. 3, č. 4 (2006), s. 67-76 ISSN 1214-9705 R&D Projects: GA AV ČR IAA3046305 Institutional research plan: CEZ:AV0Z30460519 Keywords : flooding of residual mining pits * dangerous geodynamic phenomena * stability of banks and slopes Subject RIV: DB - Geology ; Mineralogy

  20. A Microfluidic Method to Assess Emulsion Stability in Crude-Oil/Water Separators

    NARCIS (Netherlands)

    Krebs, T.; Schroën, C.G.P.H.; Boom, R.M.

    2011-01-01

    The control of emulsion stability and droplet size is of crucial importance for oil production, especially for the processes of crude/oil water separation and cleanup of produced water. To recover pure oil and water, coalescence between droplets needs to take place, the extent of which will depend

  1. Environmental Assessment for Slope Stabilization Projects at Fort MacArthur, San Pedro, California

    Science.gov (United States)

    2012-01-01

    effective in stabilizing slopes. The USAF and its consultants identified the most effective remedial measures that can be economically constructed within...consultants identified the most effective remedial measures that can be economically constructed with the physical and property boundary constraints...carbon tetrachloride, ammonia, hydrogen sulfide, hydrogen cyanide , and methane. The SCAB is not classified under CAAQS for any TACs (CARB 2011). EA

  2. Assessment of ploidy stability of the somatic embryogenesis process in Quercus suber L. using flow cytometry

    Czech Academy of Sciences Publication Activity Database

    Loureiro, J.; Pinto, G.; Lopes, T.; Doležel, Jaroslav; Santos, C.

    2005-01-01

    Roč. 221, - (2005), s. 815-822 ISSN 0032-0935 Institutional research plan: CEZ:AV0Z50380511 Keywords : Flow cytometry * ploidy stability * nuclear DNA content Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.108, year: 2005

  3. Degradation and stabilization of ice wedges: Implications for assessing risk of thermokarst in northern Alaska

    Science.gov (United States)

    Kanevskiy, Mikhail; Shur, Yuri; Jorgenson, Torre; Brown, Dana R. N.; Moskalenko, Nataliya; Brown, Jerry; Walker, Donald A.; Raynolds, Martha K.; Buchhorn, Marcel

    2017-11-01

    Widespread degradation of ice wedges has been observed during the last decades in numerous areas within the continuous permafrost zone of Eurasia and North America. To study ice-wedge degradation, we performed field investigations at Prudhoe Bay and Barrow in northern Alaska during 2011-2016. In each study area, a 250-m transect was established with plots representing different stages of ice-wedge degradation/stabilization. Field work included surveying ground- and water-surface elevations, thaw-depth measurements, permafrost coring, vegetation sampling, and ground-based LiDAR scanning. We described cryostratigraphy of frozen soils and stable isotope composition, analyzed environmental characteristics associated with ice-wedge degradation and stabilization, evaluated the vulnerability and resilience of ice wedges to climate change and disturbances, and developed new conceptual models of ice-wedge dynamics that identify the main factors affecting ice-wedge degradation and stabilization and the main stages of this quasi-cyclic process. We found significant differences in the patterns of ice-wedge degradation and stabilization between the two areas, and the patterns were more complex than those previously described because of the interactions of changing topography, water redistribution, and vegetation/soil responses that can interrupt or reinforce degradation. Degradation of ice wedges is usually triggered by an increase in the active-layer thickness during exceptionally warm and wet summers or as a result of flooding or disturbance. Vulnerability of ice wedges to thermokarst is controlled by the thickness of the intermediate layer of the upper permafrost, which overlies ice wedges and protects them from thawing. In the continuous permafrost zone, degradation of ice wedges rarely leads to their complete melting; and in most cases wedges eventually stabilize and can then resume growing, indicating a somewhat cyclic and reversible process. Stabilization of ice wedges

  4. Consideration of the restoring plan in subsidence prone areas through the development of ground stability assessment techniques

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Kwang-Soo; Kim, Im-Ho; Baek, Sang-Ho [Korea Institute of Geology Mining and Materials, Taejon (KR)] (and others)

    1999-12-01

    This report consists of 2 subjects. (1) Consideration of the restoring plan in subsidence prone areas through the development of ground stability assessment techniques : The number of mines at rest as well as closed have abruptly increased since the 1980's, which has caused subsidence problems around the mined areas. To protect such places from damage due to subsidence, it is necessary to develop the assessment techniques of ground stability and make restoration plan. To achieve this goal, the site investigation should have been conducted before the subsidence events occurred, but ground behaviors around the places where a vertical movement is expected and recognised in advance before the occurrence of the subsidence events. In this study ground stability analysis for the area surrounding the Moo-Geuk Mine, located close to a city, was conducted and the measurements were recorded. The objectives of the present study include, the development of a risk assessment technique for the subsidence using GIS tool, an evaluation of the numerical methods related to the site investigation and the ground stability analysis, the application of the numerical tools to the present problems. (2) Integration of coal mine data and use of remote sensing in investigation of coal mine area : This study attempt to integrate the previous geological and mining data to avoid confusions often occurred when accessing source data. And the investigation of underground mining place using remote sensing method is the other effort to assure the geographic locations of mining places as well as to find out unknown mining place. The sample region for examining the remote sensing method is the Chungnam coal field, which locates in the middle western part of South Korea. Detailed investigation was held on the Seongju area, locating north eastern part of the coal field. (author). 54 refs., tabs., figs.

  5. Protein Comparability Assessments and Potential Applicability of High Throughput Biophysical Methods and Data Visualization Tools to Compare Physical Stability Profiles

    Directory of Open Access Journals (Sweden)

    Mohammad A. Alsenaidy

    2014-03-01

    Full Text Available In this review, some of the challenges and opportunities encountered during protein comparability assessments are summarized with an emphasis on developing new analytical approaches to better monitor higher-order protein structures. Several case studies are presented using high throughput biophysical methods to collect protein physical stability data as function of temperature, agitation, ionic strength and/or solution pH. These large data sets were then used to construct empirical phase diagrams (EPDs, radar charts, and comparative signature diagrams (CSDs for data visualization and structural comparisons between the different proteins. Protein samples with different sizes, post-translational modifications, and inherent stability are presented: acidic fibroblast growth factor (FGF-1 mutants, different glycoforms of an IgG1 mAb prepared by deglycosylation, as well as comparisons of different formulations of an IgG1 mAb and granulocyte colony stimulating factor (GCSF. Using this approach, differences in structural integrity and conformational stability profiles were detected under stress conditions that could not be resolved by using the same techniques under ambient conditions (i.e., no stress. Thus, an evaluation of conformational stability differences may serve as an effective surrogate to monitor differences in higher-order structure between protein samples. These case studies are discussed in the context of potential utility in protein comparability studies.

  6. Protein comparability assessments and potential applicability of high throughput biophysical methods and data visualization tools to compare physical stability profiles.

    Science.gov (United States)

    Alsenaidy, Mohammad A; Jain, Nishant K; Kim, Jae H; Middaugh, C Russell; Volkin, David B

    2014-01-01

    In this review, some of the challenges and opportunities encountered during protein comparability assessments are summarized with an emphasis on developing new analytical approaches to better monitor higher-order protein structures. Several case studies are presented using high throughput biophysical methods to collect protein physical stability data as function of temperature, agitation, ionic strength and/or solution pH. These large data sets were then used to construct empirical phase diagrams (EPDs), radar charts, and comparative signature diagrams (CSDs) for data visualization and structural comparisons between the different proteins. Protein samples with different sizes, post-translational modifications, and inherent stability are presented: acidic fibroblast growth factor (FGF-1) mutants, different glycoforms of an IgG1 mAb prepared by deglycosylation, as well as comparisons of different formulations of an IgG1 mAb and granulocyte colony stimulating factor (GCSF). Using this approach, differences in structural integrity and conformational stability profiles were detected under stress conditions that could not be resolved by using the same techniques under ambient conditions (i.e., no stress). Thus, an evaluation of conformational stability differences may serve as an effective surrogate to monitor differences in higher-order structure between protein samples. These case studies are discussed in the context of potential utility in protein comparability studies.

  7. Balance assessment during squatting exercise: A comparison between laboratory grade force plate and a commercial, low-cost device.

    Science.gov (United States)

    Mengarelli, Alessandro; Verdini, Federica; Cardarelli, Stefano; Di Nardo, Francesco; Burattini, Laura; Fioretti, Sandro

    2018-04-11

    Testing balance through squatting exercise is a central part of many rehabilitation programs and sports and plays also an important role in clinical evaluation of residual motor ability. The assessment of center of pressure (CoP) displacement and its parametrization is commonly used to describe and analyze squat movement and the laboratory-grade force plates (FP) are the gold standard for measuring balance performances from a dynamic view-point. However, the Nintendo Wii Balance Board (NWBB) has been recently proposed as an inexpensive and easily available device for measuring ground reaction force and CoP displacement in standing balance tasks. Thus, this study aimed to compare the NWBB-CoP data with those obtained from a laboratory FP during a dynamic motor task, such as the squat task. CoP data of forty-eight subjects were acquired simultaneously from a NWBB and a FP and the analyses were performed over the descending squatting phase. Outcomes showed a very high correlation (r) and limited root-mean-square differences between CoP trajectories in anterior-posterior (r > 0.99, 1.63 ± 1.27 mm) and medial-lateral (r > 0.98, 1.01 ± 0.75 mm) direction. Spatial parameters computed from CoP displacement and ground reaction force peak presented fixed biases between NWBB and FP. Errors showed a high consistency (standard deviation < 2.4% of the FP outcomes) and a random spread distribution around the mean difference. Mean velocity is the only parameter which exhibited a tendency towards proportional values. Findings of this study suggested the NWBB as a valid device for the assessment and parametrization of CoP displacement during squatting movement. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Whole-body isometric force/torque measurements for functional assessment in neuro-rehabilitation: platform design, development and verification

    Directory of Open Access Journals (Sweden)

    Cavallo Giuseppe

    2009-10-01

    Full Text Available Abstract Background One of the main scientific and technological challenges of rehabilitation bioengineering is the development of innovative methodologies, based on the use of appropriate technological devices, for an objective assessment of patients undergoing a rehabilitation treatment. Such tools should be as fast and cheap to use as clinical scales, which are currently the daily instruments most widely used in the routine clinical practice. Methods A human-centered approach was used in the design and development of a mechanical structure equipped with eight force/torque sensors that record quantitative data during the initiation of a predefined set of Activities of Daily Living (ADL tasks, in isometric conditions. Results Preliminary results validated the appropriateness, acceptability and functionality of the proposed platform, that has become now a tool used for clinical research in three clinical centres. Conclusion This paper presented the design and development of an innovative platform for whole-body force and torque measurements on human subjects. The platform has been designed to perform accurate quantitative measurements in isometric conditions with the specific aim to address the needs for functional assessment tests of patients undergoing a rehabilitation treatment as a consequence of a stroke. The versatility of the system also enlightens several other interesting possible areas of application for therapy in neurorehabilitation, for research in basic neuroscience, and more.

  9. Energy efficiency assessment methods and tools evaluation. Bolling Air Force Base. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    McMordie, K.L.; Richman, E.E.; Keller, J.M.; Dixon, D.R.

    1995-05-01

    The goal of the U.S. Department of Energy (DOE) Federal Energy Management Program (FEMP) is to facilitate energy-efficiency improvements at federal facilities. This is accomplished by a balanced program of technology development, facility assessment, and use of cost-sharing procurement mechanisms. Technology development focuses upon the tools, software, and procedures used to identify and evaluate energy-efficiency technologies and improvements. For facility assessment, FEMP provides metering equipment and trained analysts to federal agencies exhibiting a commitment to improve energy use efficiency. To assist in procurement of energy-efficiency measures, FEMP helps federal agencies devise and implement performance contracting and utility demand-side management strategies. Pacific Northwest Laboratory (PNL) supports the FEMP mission of energy systems modernization. Under this charter, the Laboratory and its contractors work with federal facility energy managers to assess and implement energy-efficiency improvements at federal facilities nationwide.

  10. Rule Extraction Based on Extreme Learning Machine and an Improved Ant-Miner Algorithm for Transient Stability Assessment.

    Directory of Open Access Journals (Sweden)

    Yang Li

    Full Text Available In order to overcome the problems of poor understandability of the pattern recognition-based transient stability assessment (PRTSA methods, a new rule extraction method based on extreme learning machine (ELM and an improved Ant-miner (IAM algorithm is presented in this paper. First, the basic principles of ELM and Ant-miner algorithm are respectively introduced. Then, based on the selected optimal feature subset, an example sample set is generated by the trained ELM-based PRTSA model. And finally, a set of classification rules are obtained by IAM algorithm to replace the original ELM network. The novelty of this proposal is that transient stability rules are extracted from an example sample set generated by the trained ELM-based transient stability assessment model by using IAM algorithm. The effectiveness of the proposed method is shown by the application results on the New England 39-bus power system and a practical power system--the southern power system of Hebei province.

  11. Stability Assessment and Tuning of an Adaptively Augmented Classical Controller for Launch Vehicle Flight Control

    Science.gov (United States)

    VanZwieten, Tannen; Zhu, J. Jim; Adami, Tony; Berry, Kyle; Grammar, Alex; Orr, Jeb S.; Best, Eric A.

    2014-01-01

    Recently, a robust and practical adaptive control scheme for launch vehicles [ [1] has been introduced. It augments a classical controller with a real-time loop-gain adaptation, and it is therefore called Adaptive Augmentation Control (AAC). The loop-gain will be increased from the nominal design when the tracking error between the (filtered) output and the (filtered) command trajectory is large; whereas it will be decreased when excitation of flex or sloshing modes are detected. There is a need to determine the range and rate of the loop-gain adaptation in order to retain (exponential) stability, which is critical in vehicle operation, and to develop some theoretically based heuristic tuning methods for the adaptive law gain parameters. The classical launch vehicle flight controller design technics are based on gain-scheduling, whereby the launch vehicle dynamics model is linearized at selected operating points along the nominal tracking command trajectory, and Linear Time-Invariant (LTI) controller design techniques are employed to ensure asymptotic stability of the tracking error dynamics, typically by meeting some prescribed Gain Margin (GM) and Phase Margin (PM) specifications. The controller gains at the design points are then scheduled, tuned and sometimes interpolated to achieve good performance and stability robustness under external disturbances (e.g. winds) and structural perturbations (e.g. vehicle modeling errors). While the GM does give a bound for loop-gain variation without losing stability, it is for constant dispersions of the loop-gain because the GM is based on frequency-domain analysis, which is applicable only for LTI systems. The real-time adaptive loop-gain variation of the AAC effectively renders the closed-loop system a time-varying system, for which it is well-known that the LTI system stability criterion is neither necessary nor sufficient when applying to a Linear Time-Varying (LTV) system in a frozen-time fashion. Therefore, a

  12. Assessing LULC changes over Chilika Lake watershed in Eastern India using Driving Force Analysis

    Science.gov (United States)

    Jadav, S.; Syed, T. H.

    2017-12-01

    Rapid population growth and industrial development has brought about significant changes in Land Use Land Cover (LULC) of many developing countries in the world. This study investigates LULC changes in the Chilika Lake watershed of Eastern India for the period of 1988 to 2016. The methodology involves pre-processing and classification of Landsat satellite images using support vector machine (SVM) supervised classification algorithm. Results reveal that `Cropland', `Emergent Vegetation' and `Settlement' has expanded over the study period by 284.61 km², 106.83 km² and 98.83 km² respectively. Contemporaneously, `Lake Area', `Vegetation' and `Scrub Land' have decreased by 121.62 km², 96.05 km² and 80.29 km² respectively. This study also analyzes five major driving force variables of socio-economic and climatological factors triggering LULC changes through a bivariate logistic regression model. The outcome gives credible relative operating characteristics (ROC) value of 0.76 that indicate goodness fit of logistic regression model. In addition, independent variables like distance to drainage network and average annual rainfall have negative regression coefficient values that represent decreased rate of dependent variable (changed LULC) whereas independent variables (population density, distance to road and distance to railway) have positive regression coefficient indicates increased rate of changed LULC . Results from this study will be crucial for planning and restoration of this vital lake water body that has major implications over the society and environment at large.

  13. Assessment of placental stiffness using acoustic radiation force impulse elastography in pregnant women with fetal anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Alan, Bircan; Goya, Cemil; Tunc, Senem; Teke, Memik; Hattapoglu, Salih [Dicle University Medical Faculty, Diyarbakir (Turkmenistan)

    2016-04-15

    We aimed to evaluate placental stiffness measured by acoustic radiation force impulse (ARFI) elastography in pregnant women in the second trimester with a normal fetus versus those with structural anomalies and non-structural findings. Forty pregnant women carrying a fetus with structural anomalies diagnosed sonographically at 18-28 weeks of gestation comprised the study group. The control group consisted of 34 healthy pregnant women with a sonographically normal fetus at a similar gestational age. Placental shear wave velocity (SWV) was measured by ARFI elastography and compared between the two groups. Structural anomalies and non-structural findings were scored based on sonographic markers. Placental stiffness measurements were compared among fetus anomaly categories. Doppler parameters of umbilical and uterine arteries were compared with placental SWV measurements. All placental SWV measurements, including minimum SWV, maximum SWV, and mean SWV were significantly higher in the study group than the control group ([0.86 ± 0.2, 0.74 ± 0.1; p < 0.001], [1.89 ± 0.7, 1.59 ± 0.5; p = 0.04], and [1.26 ± 0.4, 1.09 ± 0.2; p = 0.01]), respectively. Placental stiffness evaluated by ARFI elastography during the second trimester in pregnant women with fetuses with congenital structural anomalies is higher than that of pregnant women with normal fetuses.

  14. Assessment of liver steatosis in chicken by using acoustic radiation force impulse imaging: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Guzman Aroca, Florentina; Serrano, Laura; Berna-Serna, Juan D.; Reus, Manuel [Virgen de la Arrixaca University Hospital, Department of Radiology, El Palmar, Murcia (Spain); Ayala, Ignacio [University of Murcia, Department of Animal Medicine and Surgery, Murcia (Spain); Castell, Maria T. [University of Murcia, Department of Cell Biology, Murcia (Spain); Garcia-Perez, Bartolome [Virgen de la Arrixaca University Hospital, Internal Medicine Service, El Palmar, Murcia (Spain)

    2010-10-15

    To evaluate acoustic radiation force impulse (ARFI) imaging as a non-invasive tool for quantification of the grades of liver steatosis in chickens. We used two different diets: a standard diet (SD group) and a hyperlipidaemic diet (HD group). The ARFI technique was performed in all the animals in the right hepatic lobe and shear wave velocity (SWV) was measured and expressed in metres per second (m/s). Plasma lipid levels were analysed. Steatosis was quantified by using semiquantitative analysis. Statistical analysis was used and Pearson's correlation coefficient was calculated. Mean SWV was 0.94 {+-} 0.16 m/s (range 0.8-1.3 m/s) in the SD group and 1.91 {+-} 0.25 m/s (range 1.3-2.2 m/s) in the HD group (p < 0.001). The lowest SWVs ({<=}1.3 m/s) corresponded to the chickens in the SD group, with 100% of the animals returning a score of 0, whereas the range of SWV in the HD group chickens was between 1.6 and 2.2 m/s. A substantial correlation was observed between SWVs with histological semiquantitative analysis of steatosis (r = 0.85, p < 0.001). ARFI imaging is a non-invasive diagnostic tool that allows discrimination between the grades of liver steatosis in chickens. (orig.)

  15. Assessment of liver steatosis in chicken by using acoustic radiation force impulse imaging: preliminary results

    International Nuclear Information System (INIS)

    Guzman Aroca, Florentina; Serrano, Laura; Berna-Serna, Juan D.; Reus, Manuel; Ayala, Ignacio; Castell, Maria T.; Garcia-Perez, Bartolome

    2010-01-01

    To evaluate acoustic radiation force impulse (ARFI) imaging as a non-invasive tool for quantification of the grades of liver steatosis in chickens. We used two different diets: a standard diet (SD group) and a hyperlipidaemic diet (HD group). The ARFI technique was performed in all the animals in the right hepatic lobe and shear wave velocity (SWV) was measured and expressed in metres per second (m/s). Plasma lipid levels were analysed. Steatosis was quantified by using semiquantitative analysis. Statistical analysis was used and Pearson's correlation coefficient was calculated. Mean SWV was 0.94 ± 0.16 m/s (range 0.8-1.3 m/s) in the SD group and 1.91 ± 0.25 m/s (range 1.3-2.2 m/s) in the HD group (p < 0.001). The lowest SWVs (≤1.3 m/s) corresponded to the chickens in the SD group, with 100% of the animals returning a score of 0, whereas the range of SWV in the HD group chickens was between 1.6 and 2.2 m/s. A substantial correlation was observed between SWVs with histological semiquantitative analysis of steatosis (r = 0.85, p < 0.001). ARFI imaging is a non-invasive diagnostic tool that allows discrimination between the grades of liver steatosis in chickens. (orig.)

  16. Extending the Cooperative Phenotype: Assessing the Stability of Cooperation across Countries.

    Science.gov (United States)

    Reigstad, Amanda G; Strømland, Eirik A; Tinghög, Gustav

    2017-01-01

    This paper studies whether individual cooperation is stable across settings and over time. Involving more than 7,000 subjects on two different continents, this study documents positive correlation in cooperative behavior across economic games in Norway, Sweden, Austria, and the United States. The game measures also correlate with a tendency to make deontological judgments in moral dilemmas, and display of general trust toward strangers. Using time-variation in the data, we test whether temporal stability of behavior is similar in the United States and Norway, and find similar stability estimates for both the American and Norwegian samples. The findings here provide further evidence of the existence of a stable behavioral inclination toward prosociality - a "cooperative phenotype," as it has recently been termed. Also in line with previous research, we find that punishment and cooperation seem to be uncorrelated.

  17. Extending the Cooperative Phenotype: Assessing the Stability of Cooperation across Countries

    Directory of Open Access Journals (Sweden)

    Amanda G. Reigstad

    2017-11-01

    Full Text Available This paper studies whether individual cooperation is stable across settings and over time. Involving more than 7,000 subjects on two different continents, this study documents positive correlation in cooperative behavior across economic games in Norway, Sweden, Austria, and the United States. The game measures also correlate with a tendency to make deontological judgments in moral dilemmas, and display of general trust toward strangers. Using time-variation in the data, we test whether temporal stability of behavior is similar in the United States and Norway, and find similar stability estimates for both the American and Norwegian samples. The findings here provide further evidence of the existence of a stable behavioral inclination toward prosociality – a “cooperative phenotype,” as it has recently been termed. Also in line with previous research, we find that punishment and cooperation seem to be uncorrelated.

  18. Thermodynamic assessment of the stabilization effect in deformed shape memory alloy martensite

    International Nuclear Information System (INIS)

    Kato, Hiroyuki; Yasuda, Yohei; Sasaki, Kazuaki

    2011-01-01

    When a martensitic shape memory alloy is deformed, the reverse transformation occurs at higher temperature than that of undeformed martensite. This is a typical case of the stabilization effect of martensite that is commonly observed in shape memory alloys. Regarding previous results measured by electric resistance and/or dilatometoric methods in NiTi and CuAlNi shape memory alloys, this study has performed calorimetric measurement in these alloys in order to re-examine the stabilization effect in terms of thermodynamics. Experimental evidence for appreciable changes in the reverse transformation temperature due to variant change of the martensite is presented. The elastic energy stored in the deformed martensite and the irreversible energy dissipated during the reverse transformation are estimated from the transformation temperatures, the stress-strain curves of the martensite and the latent heat of transformation. The temperatures of the reverse martensitic transformation have been related to these energies in explicit form.

  19. An assessment of mean-field mixed semiclassical approaches: Equilibrium populations and algorithm stability

    International Nuclear Information System (INIS)

    Bellonzi, Nicole; Jain, Amber; Subotnik, Joseph E.

    2016-01-01

    We study several recent mean-field semiclassical dynamics methods, focusing on the ability to recover detailed balance for long time (equilibrium) populations. We focus especially on Miller and Cotton’s [J. Phys. Chem. A 117, 7190 (2013)] suggestion to include both zero point electronic energy and windowing on top of Ehrenfest dynamics. We investigate three regimes: harmonic surfaces with weak electronic coupling, harmonic surfaces with strong electronic coupling, and anharmonic surfaces with weak electronic coupling. In most cases, recent additions to Ehrenfest dynamics are a strong improvement upon mean-field theory. However, for methods that include zero point electronic energy, we show that anharmonic potential energy surfaces often lead to numerical instabilities, as caused by negative populations and forces. We also show that, though the effect of negative forces can appear hidden in harmonic systems, the resulting equilibrium limits do remain dependent on any windowing and zero point energy parameters.

  20. Experimental assessment of dry stone retaining wall stability on a rigid foundation

    OpenAIRE

    Villemus , B.; Morel , J.C.; Boutin , C.

    2007-01-01

    International audience; Dry stone masonry retaining walls are present in the majority of mountainous areas all around the world, but the technique is marginal today in developed countries. The emergence of the concept of sustainable development calls for renewed use of this technique, both for the repair of existing retaining walls and the building of new ones. The objective of this research was to seek the knowledge necessary to ensure the stability of these structures, using experimental in...

  1. Random matrix theory filters in portfolio optimisation: A stability and risk assessment

    Science.gov (United States)

    Daly, J.; Crane, M.; Ruskin, H. J.

    2008-07-01

    Random matrix theory (RMT) filters, applied to covariance matrices of financial returns, have recently been shown to offer improvements to the optimisation of stock portfolios. This paper studies the effect of three RMT filters on the realised portfolio risk, and on the stability of the filtered covariance matrix, using bootstrap analysis and out-of-sample testing. We propose an extension to an existing RMT filter, (based on Krzanowski stability), which is observed to reduce risk and increase stability, when compared to other RMT filters tested. We also study a scheme for filtering the covariance matrix directly, as opposed to the standard method of filtering correlation, where the latter is found to lower the realised risk, on average, by up to 6.7%. We consider both equally and exponentially weighted covariance matrices in our analysis, and observe that the overall best method out-of-sample was that of the exponentially weighted covariance, with our Krzanowski stability-based filter applied to the correlation matrix. We also find that the optimal out-of-sample decay factors, for both filtered and unfiltered forecasts, were higher than those suggested by Riskmetrics [J.P. Morgan, Reuters, Riskmetrics technical document, Technical Report, 1996. http://www.riskmetrics.com/techdoc.html], with those for the latter approaching a value of α=1. In conclusion, RMT filtering reduced the realised risk, on average, and in the majority of cases when tested out-of-sample, but increased the realised risk on a marked number of individual days-in some cases more than doubling it.

  2. Direct Drive Synchronous Machine Models for Stability Assessment of Wind Farms

    Energy Technology Data Exchange (ETDEWEB)

    Poeller, Markus; Achilles, Sebastian [DIgSILENT GmbH, Gomaringen (Germany)

    2003-11-01

    The increasing size of wind farms requires power system stability analysis including dynamic wind generator models. For turbines above 1MW doubly-fed induction machines are the most widely used concept. However, especially in Germany, direct-drive wind generators based on converter-driven synchronous generator concepts have reached considerable market penetration. This paper presents converter driven synchronous generator models of various order that can be used for simulating transients and dynamics in a very wide time range.

  3. Assessment of the availability of As and Pb in soils after in situ stabilization.

    Science.gov (United States)

    Zhang, Wanying; Yang, Jie; Li, Zhongyuan; Zhou, Dongmei; Dang, Fei

    2017-10-01

    The in situ stabilization has been widely used to remediate metal-contaminated soil. However, the long-term retaining performance of heavy metals and the associated risk after in situ stabilization remains unclear and has evoked amounting concerns. Here, Pb- or As-contaminated soil was stabilized by a commercial amendment. The availability of Pb and As after in situ stabilization were estimated by ten different in vitro chemical extractions and DGT technique. After amendment application, a significant decline in extractable Pb or As was observed in treatments of Milli-Q water, 0.01 M CaCl 2 , 0.1 M NaNO 3 , 0.05 M (NH 4 ) 2 SO 4 , and 0.43 M HOAc. Potential available metal(loid)s determined by DGT also showed remarkable reduction. Meanwhile, the results of in vivo uptake assays demonstrated that Pb concentrations in shoots of ryegrass Lolium perenne L. declined to 12% of the control samples, comparable to the extraction ratio of 0.1 M NaNO 3 (15.8%) and 0.05 M (NH 4 ) 2 SO 4 (17.3%). For As-contaminated soil, 0.43 M HOAC provided a better estimation of relative phytoavailability (64.6 vs. 65.4% in ryegrass) compared to other extraction methods. We propose that 0.1 M NaNO 3 or 0.05 M (NH 4 ) 2 SO 4 for Pb and 0.43 M HOAc for As may serve as surrogate measures to estimate the lability of metal(loid)s after soil remediation of the tested contaminated soils. Further studies over a wider range of soil types and amendments are necessary to validate extraction methods.

  4. Slope Stability Assessment of the Sarcheshmeh Landslide, Northeast Iran, Investigated Using InSAR and GPS Observations

    Directory of Open Access Journals (Sweden)

    Mahdi Motagh

    2013-07-01

    Full Text Available The detection and monitoring of mass movement of susceptible slopes plays a key role in mitigating hazards and potential damage associated with creeping slopes and landslides. In this paper, we use observations from both Interferometric Synthetic Aperture Radar (InSAR and Global Positioning System (GPS to assess the slope stability of the Sarcheshmeh ancient landslide in the North Khorasan province of northeast Iran. InSAR observations were obtained by the time-series analysis of Envisat SAR images covering 2004–2006, whereas repeated GPS observations were conducted by campaign measurements during 2010–2012. Surface displacement maps of the Sarcheshmeh landslide obtained from InSAR and GPS are both indicative of slope stability. Hydrogeological analysis suggests that the multi-year drought and lower than average precipitation levels over the last decade might have contributed to the current dormancy of the Sarcheshmeh landslide.

  5. An assessment of the impact of energy insecurity on state stability in India

    International Nuclear Information System (INIS)

    Varigonda, Kesava Chandra

    2013-01-01

    This paper studies the relation between energy insecurity and state stability in India. Primarily it looks at the ways in which specific aspects of energy insecurity impact the stability of the Indian state. The paper contends that energy insecurity in the form of fuel supply and electricity supply insecurities gives rise to social and political instability, which in extreme forms could lead to state destabilisation. A combination of inadequate and unreasonably priced fuel supply gives rise to instability in the social and political spheres; if the fuel supply is also unreliable, it could lead to chronic socio-political instability. Likewise, a combination of inadequate and unreliable electricity supply could, in certain instances, cause limited social instability; if this is also accompanied by an electricity price hike, it could lead to chronic socio-political instability. Chronic socio-political instability in an already weakened state could facilitate state destabilisation. - Highlights: • Studies the impact of energy insecurity on the stability of the Indian state. • Secondary sources from press releases of the last three decades are examined. • Fuel supply and electricity supply insecurities cause socio-political instability. • Chronic socio-political instability may lead to destabilisation of a week state

  6. Moving from laboratory to real life conditions: Influence on the assessment of variability and stability of gait.

    Science.gov (United States)

    Tamburini, Paola; Storm, Fabio; Buckley, Chris; Bisi, Maria Cristina; Stagni, Rita; Mazzà, Claudia

    2018-01-01

    The availability of wearable sensors allows shifting gait analysis from the traditional laboratory settings, to daily life conditions. However, limited knowledge is available about whether alterations associated to different testing environment (e.g. indoor or outdoor) and walking protocols (e.g. free or controlled), result from actual differences in the motor behaviour of the tested subjects or from the sensitivity to these changes of the indexes adopted for the assessment. In this context, it was hypothesized that testing environment and walking protocols would not modify motor control stability in the gait of young healthy adults, who have a mature and structured gait pattern, but rather the variability of their motor pattern. To test this hypothesis, data from trunk and shank inertial sensors were collected from 19 young healthy participants during four walking tasks in different environments (indoor and outdoor) and in both controlled (i.e. following a predefined straight path) and free conditions. Results confirmed what hypothesized: variability indexes (Standard deviation, Coefficient of variation and Poincaré plots) were significantly influenced by both environment and walking conditions. Stability indexes (Harmonic ratio, Short term Lyapunov exponents, Recurrence quantification analysis and Sample entropy), on the contrary, did not highlight any change in the motor control. In conclusion, this study highlighted an influence of environment and testing condition on the assessment of specific characteristics of gait (i.e. variability and stability). In particular, for young healthy adults, both environment and testing conditions affect gait variability indexes, whereas neither affect gait stability indexes. Copyright © 2017. Published by Elsevier B.V.

  7. Needs assessment and implementation of an employee assistance program: promoting a healthier work force.

    Science.gov (United States)

    Monfils, M K

    1995-05-01

    1. The functions of a continuous quality improvement tool used by Deming--the Plan, Do, Check, Act Cycle--can be applied to the assessment, implementation, and ongoing evaluation of an Employee Assistance Program (EAP). 2. Various methods are available to assess the need for an EAP. As much data as possible should be collected to qualify and quantify the need so that management can make an informed decision and develop measures to determine program effectiveness. 3. Once an EAP is implemented, it should be monitored continually against the effectiveness measures initially developed. Using a continuous quality improvement process, the occupational health nurse and the EAP provider can establish a dynamic relationship that allows for growth beyond the original design and increased effectiveness of service to employees.

  8. Maximum dislodging forces of mandibular implant-assisted removable partial dentures: in vitro assessment.

    Science.gov (United States)

    Gharehchahi, Jafar; Asadzadeh, Nafiseh; Mirmortazavi, Amirtaher; Shakeri, Mohammad Taghi

    2013-10-01

    The initial retention of implant-assisted removable partial dentures (IARPDs) is unknown. The purpose of this in vitro study was to compare maximum dislodging forces of distal extension mandibular IARPD with two different attachments and three clasp designs. A simulated class I partially edentulous mandible was prepared with two screw-type 3.75 × 12 mm implants in the first molar regions and 2 metal-ceramic crowns on distal abutments. Fifteen bilateral distal extension frameworks were conventionally fabricated in three clasp designs (suprabulge, infrabulge, no clasp). Locator attachments were connected to the 15 denture bases with autopolymerized resin. Each specimen was subject to four types of retention pulls (main, anterior, posterior, unilateral pull) five times with a universal testing machine. Locator attachments were replaced with O-ring attachments, and the same procedure was performed. Therefore, the study groups included: IRPD with Locator attachment and suprabulge clasp (group 1), IRPD with Locator attachment and infrabulge clasp (group 2), IRPD with Locator attachment and no clasp (group 3), IRPD with O-ring attachment and suprabulge clasp (group 4), IRPD with O-ring attachment and infrabulge clasp (group 5), IRPD with O-ring attachment and no clasp (group 6). Data were analyzed using one-way ANOVA, two-way ANOVA, and Tukey tests. The highest mean value was 22.99 lb for prostheses with a Locator attachment and suprabulge clasp. The lowest retentive values were recorded for IARPDs with O-ring attachments. The results of this in vitro study suggest that the precise selection of attachments with or without clasp assemblies may affect the clinical success of mandibular IARPDs. © 2013 by the American College of Prosthodontists.

  9. Environmental Assessment for the California Space Center at Vandenberg Air Force Base, California

    Science.gov (United States)

    2010-04-08

    shallow- rooted , mesophylic plant species that Chapter 3. Affected Environment Final Draft Environmental Assessment - California Space Center...buckwheat flowers and buds where the larvae feed until maturation. Upon maturation larvae burrow into the soil and pupate, usually within the root and...terrain, sharp or protruding objects, slippery soils or mud, and biological hazards including vegetation (i.e. poison oak and stinging nettle

  10. Environmental Assessment: Construction and Operation of an Alternate Drone Launch System at Tyndall Air Force Base

    Science.gov (United States)

    2008-05-01

    Tyndall AFB completely delimit the site boundaries and render an assessment of NRHP eligibility for the undocumented portion of the site. The...Water Tyndall AFB is located within the Choctawhatchee River Basin which drains the Choctawhatchee River southward into Choctawhatchee Bay, and...the Gulf of Mexico. These systems are hydrologically connected to Choctawhatchee Bay to the west. There are no surface waters at or in the immediate

  11. Final Environmental Assessment for a Solar Power System at Davis-Monthan Air Force Tucson, Arizona

    Science.gov (United States)

    2009-09-01

    to the following factors depending on the corresponding years. Year 2005 through 2009: VOCE = .016 * Trips NOxE = .015 * Trips PM10E = .0022...Trips COE = .262 * Trips Year 2010 and beyond: VOCE = .012 * Trips NOxE = .013 * Trips PM10E = .0022 * Trips COE = .262 * Trips FINAL...ENVIRONMENTAL ASSESSMENT B-8 Solar Power System (SPS) at Davis-Monthan AFB To convert from pounds per day to tons per year: VOC (tons/yr) = VOCE * DPYII/2000

  12. Final Environmental Assessment for Stormwater Drainage Project on F. E. Warren Air Force Base, Wyoming

    Science.gov (United States)

    2005-05-01

    Taxidea taxus), raccoon (Procyon lotor hirtus), porcupine (Erethizon dorsatum), red fox (Vulpes vulpes), coyote (Canus latrans), and Wyoming ground...squirrel (Spermophilus elegans). A relatively large herd of pronghorn antelope inhabits the base. Although the pronghorn on the installation are a...part of the larger Iron Mountain herd , most reside on the installation year-round. The Storm Water Drainage Project, Draft Environmental Assessment

  13. A Health Economics Approach to US Value Assessment Frameworks-Introduction: An ISPOR Special Task Force Report [1].

    Science.gov (United States)

    Neumann, Peter J; Willke, Richard J; Garrison, Louis P

    2018-02-01

    Concerns about rising spending on prescription drugs and other areas of health care have led to multiple initiatives in the United States designed to measure and communicate the value of pharmaceuticals and other technologies for decision making. In this section we introduce the work of the International Society for Pharmacoeconomics and Outcomes Research Special Task Force on US Value Assessment Frameworks formed to review relevant perspectives and appropriate approaches and methods to support the definition and use of high-quality value frameworks. The Special Task Force was part of the International Society for Pharmacoeconomics and Outcomes Research Initiative on US Value Assessment Frameworks, which enlisted the expertise of leading health economists, concentrating on what the field of health economics can provide to help inform the development and use of value assessment frameworks. We focus on five value framework initiatives: the American College of Cardiology/American Heart Association, the American Society of Clinical Oncology, the Institute for Clinical and Economic Review, the Memorial Sloan Kettering Cancer Center, and the National Comprehensive Cancer Network. These entities differ in their missions, scope of activities, and methodological approaches. Because they are gaining visibility and some traction in the United States, it is essential to scrutinize whether the frameworks use approaches that are transparent as well as conceptually and methodologically sound. Our objectives were to describe the conceptual bases for value and its use in decision making, critically examine existing value frameworks, discuss the importance of sound conceptual underpinning, identify key elements of value relevant to specific decision contexts, and recommend good practice in value definition and implementation as well as areas for further research. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc

  14. Networked Forces in Stability Operations: 101st Airborne Division, 3/2 and 1/25 Stryker Brigades in Northern Iraq

    Science.gov (United States)

    2007-01-01

    The force comprised 160 soldiers, 19 aircraft, and 12 ground vehicles:11 An air assault force delivered by four MH-6 Little Bird helicopters and two...were correct. The C2 bird was doing the best it could to tell us how many “rights” and “lefts” to take, but a “right” and a “left” here—that is...on common tactics. The QRF included a mixture of U.S., Malaysian , and Paki- stani forces, with about 60 vehicles including tanks and armored personnel

  15. Stability Analysis of the Embankment Model

    Directory of Open Access Journals (Sweden)

    G.S. Gopalakrishna

    2009-01-01

    Full Text Available In analysis of embankment model affected by dynamic force, employment of shaking table is a scientific way in assessment of earthquake behavior. This work focused on saturated loose sandy foundation and enbankment. The results generated through the pore pressure sensors indicated pore water pressure playing main role in creation of liquefaction and stability of the system, and also revealed deformation, settlement, liquefaction intensity and time stability of system in direct correlation with the strength and characteristics of soil. One of the economical methods in stabilization of soil foundation is improvement of some part soil foundation.

  16. Technical note: use of belt grill cookery and slice shear force for assessment of pork longissimus tenderness.

    Science.gov (United States)

    Shackelford, S D; Wheeler, T L; Koohmaraie, M

    2004-01-01

    The present experiments were conducted to determine whether improved beef longissimus shear force methodology could be used to assess pork longissimus tenderness. Specifically, three experiments were conducted to: 1) determine the effect of belt grill (BG) cookery on repeatability of pork longissimus Warner-Bratzler shear force (WBSF), 2) compare the correlation of WBSF and slice shear force (SSF) with trained sensory panel tenderness ratings, and 3) estimate the repeatability of pork longissimus SSF for chops cooked with a BG. In Exp. 1 and 2, the longissimus was removed from the left side of each carcass (Exp. 1, n = 25; Exp. 2, n = 23) at 1 d postmortem and immediately frozen to maximize variation in tenderness. In Exp. 1, chops were cooked with either open-hearth electric broilers (OH) or BG, and WBSF was measured. Percentage of cooking loss was lower (P cooked with a BG (23.2%; SD = 1.7%) vs. OH (27.6%; SD = 3.0%). Estimates of the repeatability of WBSF were similar for chops cooked with OH (0.61) and BG (0.59). Although significant (P cooking methods accounted for less than 5% of the total variation in WBSF. In Exp. 2, the correlation of SSF (r = -0.72; P cooked with BG, and SSF was determined. The repeatability of SSF was 0.90, which is comparable to repeatability estimates for beef and lamb. Use of BG cookery and SSF could facilitate the collection of accurate pork longissimus tenderness data. Time and labor savings associated with BG cookery and the SSF technique should help to decrease research costs.

  17. Hydrothermal research and development assessment. Task Force report: projections for direct-heat applications

    Energy Technology Data Exchange (ETDEWEB)

    1982-04-01

    Low and moderate temperature hydrothermal resources suitable for direct-heat applications have been identified in 37 states. The extent to which three resources might be used over the next 20 years were evaluated and the probable impact of Federal programs on hydrothermal resource utilization was assessed. The use types that comprise the bulk of the market were determined. Representative firms and municipalities were interviewed to determine their willingness to use hydrothermal energy, and to determine the investment decision criteria that would influence their actions. (MHR)

  18. An assessment of Movement Disorder Society Task Force diagnostic criteria for mild cognitive impairment in Parkinson's disease.

    Science.gov (United States)

    Uysal-Cantürk, P; Hanağası, H A; Bilgiç, B; Gürvit, H; Emre, M

    2018-01-01

    Cognitive impairment is one of the most disabling non-motor symptoms of Parkinson's disease. Mild cognitive impairment constitutes a major risk for the development of Parkinson's disease dementia in the course of the disease. A Movement Disorder Society Task Force proposed diagnostic criteria for mild cognitive impairment in Parkinson's disease (PD-MCI), comprising two operational levels: Level I and Level II. The objective of our study was to test the accuracy of Level I versus Level II diagnostic criteria. Eighty-six consecutive patients with Parkinson's disease were screened and 68 patients without dementia or depression were included in the study. We used the Montreal Cognitive Assessment, Mini-Mental State Examination and Addenbrooke's Cognitive Evaluation-R screening tools for Level I and an extensive neuropsychological battery for Level II assessment. We first diagnosed PD-MCI on the basis of Level II assessment and then calculated sensitivity, specificity and area under the receiver-operator characteristics curve, comparing the performance of the three screening batteries. None of the three screening batteries proposed for Level I assessment provided satisfactory combined sensitivity and specificity for detecting PD-MCI, and their performance was similar. Using the Level II criteria, 29 patients (43%) were diagnosed as having PD-MCI. Lowest cut-off levels that provided at least 80% sensitivity were 24 for the Montreal Cognitive Assessment, 29 for the Mini-Mental State Examination and 87 for the Addenbrooke's Cognitive Evaluation-R. However, specificity levels were below 80% at these cut-off levels. We conclude that Level I assessment alone using screening batteries is not sufficiently sensitive/specific to detect PD-MCI. © 2017 EAN.

  19. Hybrid dynamic stabilization: a biomechanical assessment of adjacent and supraadjacent levels of the lumbar spine.

    Science.gov (United States)

    Mageswaran, Prasath; Techy, Fernando; Colbrunn, Robb W; Bonner, Tara F; McLain, Robert F

    2012-09-01

    The object of this study was to evaluate the effect of hybrid dynamic stabilization on adjacent levels of the lumbar spine. Seven human spine specimens from T-12 to the sacrum were used. The following conditions were implemented: 1) intact spine; 2) fusion of L4-5 with bilateral pedicle screws and titanium rods; and 3) supplementation of the L4-5 fusion with pedicle screw dynamic stabilization constructs at L3-4, with the purpose of protecting the L3-4 level from excessive range of motion (ROM) and to create a smoother motion transition to the rest of the lumbar spine. An industrial robot was used to apply continuous pure moment (± 2 Nm) in flexion-extension with and without a follower load, lateral bending, and axial rotation. Intersegmental rotations of the fused, dynamically stabilized, and adjacent levels were measured and compared. In flexion-extension only, the rigid instrumentation at L4-5 caused a 78% decrease in the segment's ROM when compared with the intact specimen. To compensate, it caused an increase in motion at adjacent levels L1-2 (45.6%) and L2-3 (23.2%) only. The placement of the dynamic construct at L3-4 decreased the operated level's ROM by 80.4% (similar stability as the fusion at L4-5), when compared with the intact specimen, and caused a significant increase in motion at all tested adjacent levels. In flexion-extension with a follower load, instrumentation at L4-5 affected only a subadjacent level, L5-sacrum (52.0%), while causing a reduction in motion at the operated level (L4-5, -76.4%). The dynamic construct caused a significant increase in motion at the adjacent levels T12-L1 (44.9%), L1-2 (57.3%), and L5-sacrum (83.9%), while motion at the operated level (L3-4) was reduced by 76.7%. In lateral bending, instrumentation at L4-5 increased motion at only T12-L1 (22.8%). The dynamic construct at L3-4 caused an increase in motion at T12-L1 (69.9%), L1-2 (59.4%), L2-3 (44.7%), and L5-sacrum (43.7%). In axial rotation, only the placement of

  20. Sensitivity of aerosol indirect forcing and autoconversion to cloud droplet parameterization: an assessment with the NASA Global Modeling Initiative.

    Science.gov (United States)

    Sotiropoulou, R. P.; Meshkhidze, N.; Nenes, A.

    2006-12-01

    The aerosol indirect forcing is one of the largest sources of uncertainty in assessments of anthropogenic climate change [IPCC, 2001]. Much of this uncertainty arises from the approach used for linking cloud droplet number concentration (CDNC) to precursor aerosol. Global Climate Models (GCM) use a wide range of cloud droplet activation mechanisms ranging from empirical [Boucher and Lohmann, 1995] to detailed physically- based formulations [e.g., Abdul-Razzak and Ghan, 2000; Fountoukis and Nenes, 2005]. The objective of this study is to assess the uncertainties in indirect forcing and autoconversion of cloud water to rain caused by the application of different cloud droplet parameterization mechanisms; this is an important step towards constraining the aerosol indirect effects (AIE). Here we estimate the uncertainty in indirect forcing and autoconversion rate using the NASA Global Model Initiative (GMI). The GMI allows easy interchange of meteorological fields, chemical mechanisms and the aerosol microphysical packages. Therefore, it is an ideal tool for assessing the effect of different parameters on aerosol indirect forcing. The aerosol module includes primary emissions, chemical production of sulfate in clear air and in-cloud aqueous phase, gravitational sedimentation, dry deposition, wet scavenging in and below clouds, and hygroscopic growth. Model inputs include SO2 (fossil fuel and natural), black carbon (BC), organic carbon (OC), mineral dust and sea salt. The meteorological data used in this work were taken from the NASA Data Assimilation Office (DAO) and two different GCMs: the NASA GEOS4 finite volume GCM (FVGCM) and the Goddard Institute for Space Studies version II' (GISS II') GCM. Simulations were carried out for "present day" and "preindustrial" emissions using different meteorological fields (i.e. DAO, FVGCM, GISS II'); cloud droplet number concentration is computed from the correlations of Boucher and Lohmann [1995], Abdul-Razzak and Ghan [2000

  1. Thermal stability of hepatitis E virus assessed by a molecular biological approach

    Directory of Open Access Journals (Sweden)

    Appel Bernd

    2011-10-01

    Full Text Available Abstract Background Hepatitis E virus (HEV is a pathogen of emerging concern in industrialized countries. The consumption of wild boar meat has been identified as one risk factor for autochthonous HEV infections. Only limited information is available about thermal stability of HEV, mainly due to the lack of rapid and efficient cell culture systems for measurement of HEV infectivity. Methods A molecular biological method was implemented in order to distinguish disassembled from intact viral particles using RNase treatment followed by quantitative real-time RT-PCR. The method was applied to a wild boar liver suspension containing HEV genotype 3. Results Time-course analyses indicated that the decline of protected RNA could be described by a biphasic model with an initial decrease followed by a stationary phase. The stationary phase was reached after 1 hour at 4°C, 3 days at 22°C and 7 days at 37°C with log reductions of 0.34, 0.45 and 1.24, respectively. Protected RNA was detectable until the end of the experiments at day 50 or 70. Heat exposure for 1 minute resulted in a log reduction of 0.48 at 70°C and increased with higher temperatures to 3.67 at 95°C. Although HEV infectivity titration by inoculation of the liver suspension onto three cell lines did not succeed, the results of the RNase-based method are in accordance with published cell culture-based data. Conclusions Measurement of intact viral particles using the RNase-based method may provide data on the stability of RNA viruses when cell culture-based infectivity titrations are not efficient or not available. The method enables processing of large sample numbers and may be suitable to estimate stability of HEV in different types of food.

  2. Fast Dynamic Simulation-Based Small Signal Stability Assessment and Control

    Energy Technology Data Exchange (ETDEWEB)

    Acharya, Naresh [General Electric Company, Fairfield, CT (United States); Baone, Chaitanya [General Electric Company, Fairfield, CT (United States); Veda, Santosh [General Electric Company, Fairfield, CT (United States); Dai, Jing [General Electric Company, Fairfield, CT (United States); Chaudhuri, Nilanjan [General Electric Company, Fairfield, CT (United States); Leonardi, Bruno [General Electric Company, Fairfield, CT (United States); Sanches-Gasca, Juan [General Electric Company, Fairfield, CT (United States); Diao, Ruisheng [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wu, Di [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Huang, Zhenyu [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhang, Yu [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jin, Shuangshuang [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zheng, Bin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chen, Yousu [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-12-31

    Power grid planning and operation decisions are made based on simulation of the dynamic behavior of the system. Enabling substantial energy savings while increasing the reliability of the aging North American power grid through improved utilization of existing transmission assets hinges on the adoption of wide-area measurement systems (WAMS) for power system stabilization. However, adoption of WAMS alone will not suffice if the power system is to reach its full entitlement in stability and reliability. It is necessary to enhance predictability with "faster than real-time" dynamic simulations that will enable the dynamic stability margins, proactive real-time control, and improve grid resiliency to fast time-scale phenomena such as cascading network failures. Present-day dynamic simulations are performed only during offline planning studies, considering only worst case conditions such as summer peak, winter peak days, etc. With widespread deployment of renewable generation, controllable loads, energy storage devices and plug-in hybrid electric vehicles expected in the near future and greater integration of cyber infrastructure (communications, computation and control), monitoring and controlling the dynamic performance of the grid in real-time would become increasingly important. The state-of-the-art dynamic simulation tools have limited computational speed and are not suitable for real-time applications, given the large set of contingency conditions to be evaluated. These tools are optimized for best performance of single-processor computers, but the simulation is still several times slower than real-time due to its computational complexity. With recent significant advances in numerical methods and computational hardware, the expectations have been rising towards more efficient and faster techniques to be implemented in power system simulators. This is a natural expectation, given that the core solution algorithms of most commercial simulators were developed

  3. Assessment of soil stabilization by chemical extraction and bioaccumulation using earthworm, Eisenia fetida

    Science.gov (United States)

    Lee, Byung-Tae; Abd Aziz, Azilah; Han, Heop Jo; Kim, Kyoung-Woong

    2014-05-01

    Soil stabilization does not remove heavy metals from contaminated soil, but lowers their exposures to ecosystem. Thus, it should be evaluated by measuring the fractions of heavy metals which are mobile and/or bioavailable in soils. The study compared several chemical extractions which intended to quantify the mobile or bioaccessible fractions with uptake and bioaccumulation by earthworm, Eisenia fetida. Soil samples were taken from the abandoned mine area contaminated with As, Cd, Cu, Pb and/or Zn. To stabilize heavy metals, the soils were amended with limestone and steel slag at 5% and 2% (w/w), respectively. All chemical extractions and earthworm tests were applied to both the contaminated and the stabilized soils with triplicates. The chemical extractions consisted of six single extractions which were 0.01M CaCl2 (unbufferred), EDTA or DTPA (chelating), TCLP (acidic), Mehlich 3 (mixture), and aqua regia (peudo-total). Sequential extractions were also applied to fractionate heavy metals in soils. In earthworm tests, worms were exposed to the soils for uptake of heavy metals. After 28 days of exposure to soils, worms were transferred to clean soils for elimination. During the tests, three worms were randomly collected at proper sampling events. Worms were rinsed with DI water and placed on moist filter paper for 48 h for depuration. Filter paper was renewed at 24 h to prevent coprophagy. The worms were killed with liquid nitrogen, dried in the oven, and digested with aqua regia for ICP-MS analysis. In addition to the bioaccumulation, several toxicity endpoints were observed such as burrowing time, mortality, cocoon production, and body weight changes. Toxicokinetics was applied to determine the uptake and elimination heavy metals by the earthworms. Bioaccumulation factor (BAF) was estimated using total metal concentrations and body burdens. Pearson correlation and simple linear regression were applied to evaluate the relationship between metal fractions by single

  4. Numerical assessment of efficiency and control stability of an HTS synchronous motor

    Energy Technology Data Exchange (ETDEWEB)

    Xian Wei; Yuan Weijia; Coombs, T A, E-mail: wx210@cam.ac.u [Electronic, Power and Energy Conversion Group, Engineering Department, Cambridge University, 9 JJ Thomson Avenue, Cambridge CB3 0FA (United Kingdom)

    2010-06-01

    A high temperature superconducting (HTS) permanent magnet synchronous motor (PMSM) is designed and developed in Cambridge University. It is expected to become cost competitive with the conventional PMSM owing to its high efficiency, high power density, high torque density, etc. The structure and parameters of HTS PMSM are detailed. Both AC losses by transport current and applied filed in stator armature winding of HTS PMSM are also analyzed. Computed and simulated results of the characteristics of the HTS PMSM and conventional PMSM are compared. The improvement on stability of direct torque control (DTC) on the HTS PMSM is estimated, and proved by simulation on Matlab/Simulink.

  5. On the stability of nongyrotropic ion populations: A first (analytic and simulation) assessment

    International Nuclear Information System (INIS)

    Brinca, A.L.; Borda De Agua, L.; Winske, D.

    1993-01-01

    Nongyrotropic particle populations have been observed in various space plasmas, and invoked to explain different observations within space plasmas. The authors consider waves whose frequency is below the lower hybrid frequency. They look at the stability of such low frequency waves propagating in a magnetoplasma with nongyrotropic ion populations. They derive wave equations and dispersion relations. They find that the introduction of nongyrotropy results in the coupling of wave eigenmodes, and the enhancement of instability growth rates. They consider the question of the instability growth rates in this paper

  6. Assessing the attractive/repulsive force balance in axial cyclohexane C-Hax ···Yax contacts: A combined computational analysis in monosubstituted cyclohexanes.

    Science.gov (United States)

    Silva Lopez, Carlos; Nieto Faza, Olalla; De Proft, Frank; Kolocouris, Antonios

    2016-11-15

    The interactions of axial substituents in monosubstituted cyclohexane rings are studied in this work using an array of different computational techniques. Additionally, the anomalous axial preference for some bulky substituents is related to stabilizing dispersion interactions. We find that the C-H ax ···Y ax contacts for various substituents with distances ranging from 2 to ∼5 Å may include attractive dispersion forces that can affect the conformational equilibrium; these forces co-exist with Pauli repulsive forces effected by Y ax group due to van der Waals sphere penetration. At distances between 2 and 3 Å stabilizing electron transfer interactions were calculated and the combination of natural bond orbital and QTAIM analysis showed that, in certain cases, Y ax  =  t Bu, C ax -O or C ax  = O or S ax  = O or C ax  = S this interaction can be characterized as an improper H-bond. DFT-D3 and non-covalent interactions calculations (NCIs) in cyclohexane derivatives with Y ax  = SiOR 3 including H Yax ···H cy surfaces at distances ranging between 4 and 6 Å suggest that dispersion has a clear effect on the experimentally observed stabilization of the axial conformer. NCIs computed from the reduced density gradient help to visually identify and analyze these interactions. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Uncertainty in real-time voltage stability assessment methods based on Thevenin equivalent due to PMU’s accuracy

    DEFF Research Database (Denmark)

    Perez, Angel; Møller, Jakob Glarbo; Jóhannsson, Hjörtur

    2014-01-01

    This article studies the influence of PMU’s accuracy in voltage stability assessment, considering the specific case of Th ́ evenin equivalent based methods that include wide-area information in its calculations. The objective was achieved by producing a set of synthesized PMU measurements from...... a time domain simulation and using the Monte Carlo method to reflect the accuracy for the PMUs. This is given by the maximum value for the Total Vector Error defined in the IEEE standard C37.118. Those measurements allowed to estimate the distribution pa- rameters (mean and standard deviation...

  8. Assessment of effectiveness of anti-seismic measures in stabilization project of ChNPP shelter object

    International Nuclear Information System (INIS)

    Kondrat'ev, S.N.; Kritskij, V.B.; Ryzhov, D.I.; Shugajlo, A.P.; Shugajlo, Al.P.; Prabkhakara, M.

    2004-01-01

    The major factors, which may lead to the collapse of the Shelter object (SO) civil structures, are extreme natural phenomena and among them earthquake. In order to raise the resistance of the SO civil structure to seismic and other significant loads and to reduce the risk of their collapse ChNPP requested KSK Consortium to develop the SO Detailed Design for stabilization. At the present work the results of assessment of anti-seismic measures are given based on results of a technical review of the Detailed Design

  9. Assessing deep-seated landslide susceptibility using 3-D groundwater and slope-stability analyses, southwestern Seattle, Washington

    Science.gov (United States)

    Brien, Dianne L.; Reid, Mark E.

    2008-01-01

    In Seattle, Washington, deep-seated landslides on bluffs along Puget Sound have historically caused extensive damage to land and structures. These large failures are controlled by three-dimensional (3-D) variations in strength and pore-water pressures. We assess the slope stability of part of southwestern Seattle using a 3-D limit-equilibrium analysis coupled with a 3-D groundwater flow model. Our analyses use a high-resolution digital elevation model (DEM) combined with assignment of strength and hydraulic properties based on geologic units. The hydrogeology of the Seattle area consists of a layer of permeable glacial outwash sand that overlies less permeable glacial lacustrine silty clay. Using a 3-D groundwater model, MODFLOW-2000, we simulate a water table above the less permeable units and calibrate the model to observed conditions. The simulated pore-pressure distribution is then used in a 3-D slope-stability analysis, SCOOPS, to quantify the stability of the coastal bluffs. For wet winter conditions, our analyses predict that the least stable areas are steep hillslopes above Puget Sound, where pore pressures are elevated in the outwash sand. Groundwater flow converges in coastal reentrants, resulting in elevated pore pressures and destabilization of slopes. Regions predicted to be least stable include the areas in or adjacent to three mapped historically active deep-seated landslides. The results of our 3-D analyses differ significantly from a slope map or results from one-dimensional (1-D) analyses.

  10. Stability assessment of lycopene microemulsion prepared using tomato industrial waste against various processing conditions.

    Science.gov (United States)

    Amiri-Rigi, Atefeh; Abbasi, Soleiman

    2017-11-01

    Green separation techniques are growing at a greater rate than solvent extraction as a result of the constant consumer drive to 'go natural'. Considering the increasing evidence of the health benefits of lycopene and massive tomato industrial waste, in the present study, lycopene was extracted from tomato industrial waste using microemulsion technique and its mean droplet size and size distribution was determined. Moreover, the effects of pasteurization, sterilization, freeze-thaw cycles and ultraviolet (UV) irradiation on the thermodynamic stability, turbidity and lycopene concentration of the lycopene microemulsion were monitored. Freeze-thaw cycles, pasteurization and short exposure to UV irradiation showed no or negligible influence on lycopene content and turbidity of the microemulsion. However, long exposure to UV (260 min) reduced the lycopene content and turbidity by 34% and 10%, respectively. HHST (higher-heat shorter-time) and sterilization also reduced lycopene content (25%) and increased turbidity (32%). The lycopene microemulsion showed satisfactory stability over a process where its monodispersity and nanosize could be of potential advantage to the food and related industries. Regarding the carcinogenicity of synthetic colourants, potential applications of the lycopene microemulsion include in soft drinks and minced meat, which would result in a better colour and well-documented health-promoting qualities. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  11. Resveratrol production in bioreactor: Assessment of cell physiological states and plasmid segregational stability

    Directory of Open Access Journals (Sweden)

    Margarida S. Afonso

    2015-03-01

    Full Text Available Resveratrol is a plant secondary metabolite commonly found in peanuts and grapevines with significant health benefits. Recombinant organisms can produce large amounts of resveratrol and, in this work, Escherichia coli BW27784 was used to produce resveratrol in bioreactors while monitoring cell physiology and plasmid stability through flow cytometry and real-time qPCR, respectively. Initially, the influence of culture conditions and precursor addition was evaluated in screening assays and the data gathered was used to perform the bioreactor assays, allowing the production of 160 μg/mL of resveratrol. Cellular physiology and plasmid instability affected the final resveratrol production, with lower viability and plasmid copy numbers associated with lower yields. In sum, this study describes new tools to monitor the bioprocess, evaluating the effect of culture conditions, and its correlation with cell physiology and plasmid segregational stability, in order to define a viable and scalable bioprocess to fulfill the need for larger quantities of resveratrol.

  12. Natural Stabilized Earth Panels versus Conventional Façade Systems. Economic and Environmental Impact Assessment

    Directory of Open Access Journals (Sweden)

    Carmen Galán-Marín

    2018-03-01

    Full Text Available More effective construction technologies are needed nowadays in order to reduce construction energy consumption during the life-cycle of buildings. Besides which, it is necessary to consider the economic feasibility and associated costs within the framework of these alternative technologies so as to favouring their practical implementation in the construction sector. In this sense, this paper presents an economic and environmental comparison of a new non-bearing façade construction solution based on the extruded unfired stabilized clay panels as opposed to three traditional solutions with similar physical, thermal, and aesthetic characteristics in terms of the exterior cladding. The proposed panels are a sandwich type configuration with an intermediate insulating material and two exterior pieces manufactured by extrusion with raw earth stabilized with alginate and animal wool fibers. In this paper, details of the constructive technology of the system are provided. From the results obtained, it is possible to conclude that the solution is a valid alternative from the environmental point of view, considerably reducing the Global Warming Potential and the Cumulative Energy Demand. And although the environmental improvement of the system can be considered the primary objective of this investigation, on the other hand, once executed, it will also be a competitive constructive technology from the perspective of the system’s final costs.

  13. Assessment of environmental stability of agroserous soil according to indicator of energy potential of organic substances

    Science.gov (United States)

    Murtazina, S. G.; Gaffarova, L. G.; Murtazin, MG

    2018-01-01

    Studies of the group and fractional composition of humus have determineded that the long-term use of soil (for 20 years) without the use of fertilizers (control) leads to a decrease in the content of humic acids and fulvic acids relative to the initial soil, which indicates an increase in mineralization of the soil humus. Under the influence of a long application of high doses of mineral fertilizers, the content of mobile fractions of humic and fulvic acids in the field rotation increases in the humus content. In systems of agriculture that are not balanced by organic matter, which are predominant in most farms of the Republic of Tatarstan, the use of very high doses of potassium fertilizers is not justified energetically. To compensate for losses of humus and its energy potential in calculating organic fertilizers on backgrounds with high doses of mineral fertilizers, the humification coefficients of organic residues should be increased by 30-40% during the rotational period of 5-6 years, which will reduce the loss of energy reserves and thereby improve the ecological stability of soils and the stability of agricultural landscapes

  14. Personality Stability from Childhood to Midlife: Relating Teachers’ Assessments in Elementary School to Observer- and Self-Ratings 40 Years Later

    Science.gov (United States)

    Edmonds, Grant W.; Goldberg, Lewis R.; Hampson, Sarah E.; Barckley, Maureen

    2013-01-01

    We report on the longitudinal stability of personality traits across an average 40 years in the Hawaii Personality and Health Cohort relating childhood teacher assessments of personality to adult self- and observer- reports. Stabilities based on self-ratings in adulthood were compared to those measured by the Structured Interview for the Five-Factor Model (SIFFM; Trull & Widiger, 1997), and trait ratings completed by interviewers. Although convergence between self-reports and observer-ratings was modest, childhood traits demonstrated similar levels of stability across methods in adulthood. Extraversion and Conscientiousness generally showed higher stabilities, whereas Neuroticism showed none. For Agreeableness and Intellect/Openness, stability was highest when assessed with observer-ratings. These findings are discussed in terms of differences in trait evaluativeness and observability across measurement methods. PMID:24039315

  15. Probabilistic stability and "tall" wind profiles: theory and method for use in wind resource assessment

    DEFF Research Database (Denmark)

    Kelly, Mark C.; Troen, Ib

    2016-01-01

    A model has been derived for calculating the aggregate effects of stability and the finite height of the planetary boundary layer upon the long-term mean wind profile. A practical implementation of this probabilistic extended similarity-theory model is made, including its incorporation within...... to the methodology. Results of the modeling are shown for a number of sites, with discussion of the models’ efficacy and the relative improvement shown by the new model, for situations where a user lacks local heat flux information, as well as performance of the new model using measured flux statistics. Further...... the European Wind Atlas (EWA) methodology for site-to-site application. Theoretical and practical implications of the EWA methodology are also derived and described, including unprecedented documentation of the theoretical framework encompassing vertical extrapolation, as well as some improvement...

  16. COMPARATIVE ASSESSMENT OF RICE HUSK ASH, POWDERED GLASS AND CEMENT AS LATERITIC SOIL STABILIZERS

    Directory of Open Access Journals (Sweden)

    Adebisi Ridwan

    2016-10-01

    Full Text Available This paper compares the stabilizing effects of three different materials, namely: rice husk ash, powdered glass, and cement on the properties of lateritic soil. The basic properties of the lateritic soil were first obtained through colour, moisture content determination, specific gravity, particle size distribution and Atterberg limits tests. Each of the stabilizing materials was then mixed with the lateritic soil in varying percentages of 2.5%, 5%, 7.5%, 10%, 12.5% and 15% by weight of the soil. Thereafter, compaction and California bearing ratio (CBR tests were carried out on the sample mixes to determine the effects of the materials on the lateritic soil. Chemical tests were also carried out on the samples to determine their percentage oxides composition. The compaction test showed that the highest maximum dry densities (MDD obtained for the mixed samples were 2.32 g/cm3 (at 2.5% cement addition, 2.28g/cm3 (at 5% powdered glass (PG addition and 2.18 g/cm3 (at 5% rice husk ash (RHA addition with corresponding optimum moisture contents (OMC of 10.06%, 14.3% and 12.31% respectively. The CBR tests showed that the CBR values increased in all cases as the materials were added with those of the cement and powdered glass giving the highest values and showing close semblance under unsoaked conditions. The chemical test showed that the significant oxides present in the cement, powdered glass and rice husk ash were CaO (53.60%, SiO2 (68.45% and SiO2 (89.84% respectively.

  17. Stability and variability of virulence of Phytophthorainfestans assessed in a ring test across European laboratories

    NARCIS (Netherlands)

    Andrivon, D.; Avendaño-Córcoles, J.; Cameron, A.M.; Raaij, van H.M.G.

    2011-01-01

    Determining virulence towards race-specific resistance genes is a prerequisite to understanding the response of pathogen populations to resistant cultivars, and therefore to assess the durability of these resistance genes and the performance of resistance management strategies. In Phytophthora

  18. Assessment of implant stability during various stages of healing placed immediately following extraction in an overdenture situation

    Directory of Open Access Journals (Sweden)

    Ashwin Thomas Koshy

    2017-01-01

    Full Text Available To assess the implant stability during different stages of healing in an immediate loaded implant soon after extraction. A 73-year-old female came with a chief complaint of bad smell and irritation in her lower front gum region. On examination, she was found to be completely edentulous in the maxillary arch and partially edentulous in the mandibular arch with only the canines present bilaterally. The posterior mandibular ridge was severely resorbed and hence could not be treated with a conventional mandibular complete denture. Considering the age of the patient and the preference of only a single surgical visit, we decided to plan for a conventional maxillary denture against an implant supported mandibular overdenture with two implants placed immediately after extraction of canines. The stability of these implants was assessed during the early phases of healing with the help of a resonance frequency analysis method (RFA using Osstell ISQ™. During the healing phase, implant stability quotient (ISQ values decrease by 4–5 values after installation with the lowest values at the 1st week postplacement. Following this, the ISQ values increased steadily for all implants up to 16 weeks. No significant differences were noted over time. At placement, the mean ISQ values at 33 and 43 regions were 74 and 75.2, respectively. The mean lowest ISQ values recorded at the 1st week were 58.8 and 65.4, respectively. At 16 weeks, the mean ISQ values were 70.5 and 67.9, respectively. The survival of such immediately placed implants, which are later used as overdenture supported implants, are highly predictable when the surgical and prosthetic part is done meticulously. However, there needs future studies oriented to understand better the healing pattern of immediately placed implants in extraction sockets, which would guide the clinician with the optimal loading time.

  19. Status Report on Activities of the Systems Assessment Task Force, OECD-NEA Expert Group on Accident Tolerant Fuels for LWRs

    Energy Technology Data Exchange (ETDEWEB)

    Bragg-Sitton, Shannon Michelle [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    The Organization for Economic Cooperation and Development /Nuclear Energy Agency (OECD/NEA) Nuclear Science Committee approved the formation of an Expert Group on Accident Tolerant Fuel (ATF) for LWRs (EGATFL) in 2014. Chaired by Kemal Pasamehmetoglu, INL Associate Laboratory Director for Nuclear Science and Technology, the mandate for the EGATFL defines work under three task forces: (1) Systems Assessment, (2) Cladding and Core Materials, and (3) Fuel Concepts. Scope for the Systems Assessment task force (TF1) includes definition of evaluation metrics for ATF, technology readiness level definition, definition of illustrative scenarios for ATF evaluation, and identification of fuel performance and system codes applicable to ATF evaluation. The Cladding and Core Materials (TF2) and Fuel Concepts (TF3) task forces will identify gaps and needs for modeling and experimental demonstration; define key properties of interest; identify the data necessary to perform concept evaluation under normal conditions and illustrative scenarios; identify available infrastructure (internationally) to support experimental needs; and make recommendations on priorities. Where possible, considering proprietary and other export restrictions (e.g., International Traffic in Arms Regulations), the Expert Group will facilitate the sharing of data and lessons learned across the international group membership. The Systems Assessment task force is chaired by Shannon Bragg-Sitton (Idaho National Laboratory [INL], U.S.), the Cladding Task Force is chaired by Marie Moatti (Electricite de France [EdF], France), and the Fuels Task Force is chaired by a Masaki Kurata (Japan Atomic Energy Agency [JAEA], Japan). The original Expert Group mandate was established for June 2014 to June 2016. In April 2016 the Expert Group voted to extend the mandate one additional year to June 2017 in order to complete the task force deliverables; this request was subsequently approved by the Nuclear Science Committee. This

  20. Status Report on Activities of the Systems Assessment Task Force, OECD-NEA Expert Group on Accident Tolerant Fuels for LWRs

    International Nuclear Information System (INIS)

    Bragg-Sitton, Shannon Michelle

    2016-01-01

    The Organization for Economic Cooperation and Development /Nuclear Energy Agency (OECD/NEA) Nuclear Science Committee approved the formation of an Expert Group on Accident Tolerant Fuel (ATF) for LWRs (EGATFL) in 2014. Chaired by Kemal Pasamehmetoglu, INL Associate Laboratory Director for Nuclear Science and Technology, the mandate for the EGATFL defines work under three task forces: (1) Systems Assessment, (2) Cladding and Core Materials, and (3) Fuel Concepts. Scope for the Systems Assessment task force (TF1) includes definition of evaluation metrics for ATF, technology readiness level definition, definition of illustrative scenarios for ATF evaluation, and identification of fuel performance and system codes applicable to ATF evaluation. The Cladding and Core Materials (TF2) and Fuel Concepts (TF3) task forces will identify gaps and needs for modeling and experimental demonstration; define key properties of interest; identify the data necessary to perform concept evaluation under normal conditions and illustrative scenarios; identify available infrastructure (internationally) to support experimental needs; and make recommendations on priorities. Where possible, considering proprietary and other export restrictions (e.g., International Traffic in Arms Regulations), the Expert Group will facilitate the sharing of data and lessons learned across the international group membership. The Systems Assessment task force is chaired by Shannon Bragg-Sitton (Idaho National Laboratory [INL], U.S.), the Cladding Task Force is chaired by Marie Moatti (Electricite de France [EdF], France), and the Fuels Task Force is chaired by a Masaki Kurata (Japan Atomic Energy Agency [JAEA], Japan). The original Expert Group mandate was established for June 2014 to June 2016. In April 2016 the Expert Group voted to extend the mandate one additional year to June 2017 in order to complete the task force deliverables; this request was subsequently approved by the Nuclear Science Committee. This