WorldWideScience

Sample records for strong driving force

  1. <strong>Driving forces behind the increasing cardiovascular treatment intensity.strong>>A dynamic epidemiologic model of trends in Danish cardiovascular drug utilization. strong>

    DEFF Research Database (Denmark)

    Kildemoes, Helle Wallach; Andersen, Morten

    . Objectives: To investigate the driving forces behind the increasing treatment prevalence of cardiovascular drugs, in particular statins, by means of a dynamic epidemiologic drug utilization model. Methods: Material: All Danish residents older than 20 years by January 1, 1996 (4.0 million inhabitants), were...

  2. <strong>Driving forces behind the increasing cardiovascular treatment intensity.A dynamic epidemiologic model of trends in Danish cardiovascular drug utilization.strong>

    DEFF Research Database (Denmark)

    Kildemoes, Helle Wallach; Andersen, Morten

    . Objectives: To investigate the driving forces behind the increasing treatment prevalence of cardiovascular drugs, in particular statins, by means of a dynamic epidemiologic drug utilization model. Methods: Material: All Danish residents older than 20 years by January 1, 1996 (4.0 million inhabitants), were...

  3. Technology as a driving force

    Energy Technology Data Exchange (ETDEWEB)

    Torvund, T [Norsk Hydro A/S (Norway)

    1994-12-31

    The competitiveness of the Norwegian Continental shelf has been put firmly on the agenda in Norway since the report from a working group set up by the Ministry of Industry and Energy was released in February this year. If there is to be secured a long future for oil and gas activities, a reduction in the time and costs used in the projects of the order of 40-50%, without jeopardizing the high safety and environmental standards achieved in Norway. The paper addresses how technology can be a driving force in achieving these aims. But technology alone cannot do the job. Progress and changes in several other areas are also necessary, and the new scenario also calls for improved relations between all actors in the North Sea, authorities, oil companies, contractors and labour unions. 15 figs.

  4. Technology as a driving force

    International Nuclear Information System (INIS)

    Torvund, T.

    1994-01-01

    The competitiveness of the Norwegian Continental shelf has been put firmly on the agenda in Norway since the report from a working group set up by the Ministry of Industry and Energy was released in February this year. If there is to be secured a long future for oil and gas activities, a reduction in the time and costs used in the projects of the order of 40-50%, without jeopardizing the high safety and environmental standards achieved in Norway. The paper addresses how technology can be a driving force in achieving these aims. But technology alone cannot do the job. Progress and changes in several other areas are also necessary, and the new scenario also calls for improved relations between all actors in the North Sea, authorities, oil companies, contractors and labour unions. 15 figs

  5. Chemical driving force for rafting in superalloys

    CSIR Research Space (South Africa)

    Nabarro, FRN

    1997-08-15

    Full Text Available The author provides a brief overview of the chemical driving forces for rafting in superalloys. Until recently, all theories of the driving force for rafting have considered the compositions of the two phases to be fixed, although accepting...

  6. Shewanella oneidensis cytochrome c nitrite reductase (ccNiR) does not disproportionate hydroxylamine to ammonia and nitrite, despite a strongly favorable driving force.

    Science.gov (United States)

    Youngblut, Matthew; Pauly, Daniel J; Stein, Natalia; Walters, Daniel; Conrad, John A; Moran, Graham R; Bennett, Brian; Pacheco, A Andrew

    2014-04-08

    Cytochrome c nitrite reductase (ccNiR) from Shewanella oneidensis, which catalyzes the six-electron reduction of nitrite to ammonia in vivo, was shown to oxidize hydroxylamine in the presence of large quantities of this substrate, yielding nitrite as the sole free nitrogenous product. UV-visible stopped-flow and rapid-freeze-quench electron paramagnetic resonance data, along with product analysis, showed that the equilibrium between hydroxylamine and nitrite is fairly rapidly established in the presence of high initial concentrations of hydroxylamine, despite said equilibrium lying far to the left. By contrast, reduction of hydroxylamine to ammonia did not occur, even though disproportionation of hydroxylamine to yield both nitrite and ammonia is strongly thermodynamically favored. This suggests a kinetic barrier to the ccNiR-catalyzed reduction of hydroxylamine to ammonia. A mechanism for hydroxylamine reduction is proposed in which the hydroxide group is first protonated and released as water, leaving what is formally an NH2(+) moiety bound at the heme active site. This species could be a metastable intermediate or a transition state but in either case would exist only if it were stabilized by the donation of electrons from the ccNiR heme pool into the empty nitrogen p orbital. In this scenario, ccNiR does not catalyze disproportionation because the electron-donating hydroxylamine does not poise the enzyme at a sufficiently low potential to stabilize the putative dehydrated hydroxylamine; presumably, a stronger reductant is required for this.

  7. Reconstruction of driving forces through recurrence plots

    International Nuclear Information System (INIS)

    Tanio, Masaaki; Hirata, Yoshito; Suzuki, Hideyuki

    2009-01-01

    We consider the problem of reconstructing one-dimensional driving forces only from the observations of driven systems. We extend the approach presented in a seminal paper [M.C. Casdagli, Physica D 108 (1997) 12] and propose a method that is robust and has wider applicability. By reinterpreting the work of Thiel et al. [M. Thiel, M.C. Romano, J. Kurths, Phys. Lett. A 330 (2004) 343], we formulate the reconstruction problem as a combinatorial optimization problem and relax conditions by assuming that a driving force is continuous. The method is demonstrated by using a tent map driven by an external force.

  8. Driving forces of researchers mobility

    Science.gov (United States)

    Gargiulo, Floriana; Carletti, Timoteo

    2014-05-01

    Starting from the dataset of the publication corpus of the APS during the period 1955-2009, we reconstruct the individual researchers trajectories, namely the list of the consecutive affiliations for each scholar. Crossing this information with different geographic datasets we embed these trajectories in a spatial framework. Using methods from network theory and complex systems analysis we characterise these patterns in terms of topological network properties and we analyse the dependence of an academic path across different dimensions: the distance between two subsequent positions, the relative importance of the institutions (in terms of number of publications) and some socio-cultural traits. We show that distance is not always a good predictor for the next affiliation while other factors like ``the previous steps'' of the career of the researchers (in particular the first position) or the linguistic and historical similarity between two countries can have an important impact. Finally we show that the dataset exhibit a memory effect, hence the fate of a career strongly depends from the first two affiliations.

  9. Strong economic growth driving increased electricity consumption

    International Nuclear Information System (INIS)

    Tiusanen, P.

    2000-01-01

    The Finnish economy is growing faster today than anyone dared hope only a few years ago. Growth estimates for 2000 have already had to be raised. This strong level of economic growth has been reflected in electricity consumption, which has continued to increase, despite the exceptionally warm winter. A major part of this increased electricity usage has so far been met through imports. The continued growth in electricity imports has largely been a result of the fact that the good water level situation in Sweden and Norway, together with the mild winter, has kept electricity prices exceptionally low on the Nordic electricity exchange. The short period of low temperatures seen at the end of January showed, however, that this type of temperature fluctuation, combined with the restrictions that exist in regard to transfer capacity, can serve to push Nordic exchange electricity prices to record levels. This increase in price also highlights the fact that we are approaching a situation in which capacity will be insufficient to meet demand. A truly tough winter has not been seen since the Nordic region's electricity markets were deregulated. The lesson that needs to be learnt is that Finland needs sufficient capacity of her own to meet demand even during particularly cold winters. Finland used 77.9 billion kWh of electricity last year, up 1.6% or 1.3 billion kWh on 1998. This growth was relatively evenly distributed among different user groups. This year, electricity consumption is forecast to grow by 2-3%

  10. Controlling Casimir force via coherent driving field

    Science.gov (United States)

    Ahmad, Rashid; Abbas, Muqaddar; Ahmad, Iftikhar; Qamar, Sajid

    2016-04-01

    A four level atom-field configuration is used to investigate the coherent control of Casimir force between two identical plates made up of chiral atomic media and separated by vacuum of width d. The electromagnetic chirality-induced negative refraction is obtained via atomic coherence. The behavior of Casimir force is investigated using Casimir-Lifshitz formula. It is noticed that Casimir force can be switched from repulsive to attractive and vice versa via coherent control of the driving field. This switching feature provides new possibilities of using the repulsive Casimir force in the development of new emerging technologies, such as, micro-electro-mechanical and nano-electro-mechanical systems, i.e., MEMS and NEMS, respectively.

  11. Electromotive force in strongly compressible magnetohydrodynamic turbulence

    Science.gov (United States)

    Yokoi, N.

    2017-12-01

    Variable density fluid turbulence is ubiquitous in geo-fluids, not to mention in astrophysics. Depending on the source of density variation, variable density fluid turbulence may be divided into two categories: the weak compressible (entropy mode) turbulence for slow flow and the strong compressible (acoustic mode) turbulence for fast flow. In the strong compressible turbulence, the pressure fluctuation induces a strong density fluctuation ρ ', which is represented by the density variance ( denotes the ensemble average). The turbulent effect on the large-scale magnetic-field B induction is represented by the turbulent electromotive force (EMF) (u': velocity fluctuation, b': magnetic-field fluctuation). In the usual treatment in the dynamo theory, the expression for the EMF has been obtained in the framework of incompressible or weak compressible turbulence, where only the variation of the mean density , if any, is taken into account. We see from the equation of the density fluctuation ρ', the density variance is generated by the large mean density variation ∂ coupled with the turbulent mass flux . This means that in the region where the mean density steeply changes, the density variance effect becomes relevant for the magnetic field evolution. This situation is typically the case for phenomena associated with shocks and compositional discontinuities. With the aid of the analytical theory of inhomogeneous compressible magnetohydrodynamic (MHD) turbulence, the expression for the turbulent electromotive force is investigated. It is shown that, among others, an obliqueness (misalignment) between the mean density gradient ∂ and the mean magnetic field B may contribute to the EMF as ≈χ B×∂ with the turbulent transport coefficient χ proportional to the density variance (χ ). This density variance effect is expected to strongly affect the EMF near the interface, and changes the transport properties of turbulence. In the case of an interface under the MHD slow

  12. Driving forces in the Greenlandic urbanization

    DEFF Research Database (Denmark)

    Hendriksen, Kåre

    2014-01-01

    Generally urbanization is recognised as a natural development where the population is mowing into the larger towns driven by e.g. better job opportunities, larger product and service supply and better education and health services, and it is often argued that this is also the driving forces...... support and with limited export oriented value creation. It will be disused how the previous and present urbanization interact with a sustainable development and what is the core prerequisites for sustainable towns and settlements....

  13. Strong-force theorists scoop Noble Prize

    CERN Multimedia

    Durrani, Matin

    2004-01-01

    Three US theorists have shared the 2004 Nobel Prize in Physics "for the discovery of asymptotic freedom in the theory of the strong interaction". Their theoretical work explains why quarks behave almost as free particles at high energies (½ page)

  14. Renormalization in theories with strong vector forces

    International Nuclear Information System (INIS)

    Kocic, A.

    1991-01-01

    There are not many field theories in four dimensions that have sensible ultraviolet and interesting (non-trivial) infrared behavior. At present, asymptotically free theories seem to have deserved their legitimacy and there is a strong prejudice that they might be the only ones to have such a distinction. This belief stems mostly from the fact that most of the knowledge of field theory in four dimensions comes from perturbation theory. However, nonperturbative studies of the lower dimensional theories reveal a host of interesting phenomena that are perturbative studies of the lower dimensional theories reveal a host of interesting phenomena that perturbatively inaccessible. The lack of asymptotic freedom implies that the coupling constant grows at short distances and perturbation theory breaks down. Thus, in such theories, ultraviolet behavior requires nonperturbative treatment. Recently, the interest in strongly coupled gauge theories has been revived. In particularly, four dimensional quantum electrodynamics has received considerable attention. This was motivated by the discovery of an ultraviolet stable fixed point at strong couplings. If this fixed point would turn out to be non-gaussian, then QED would be the first nontrivial nonasymptotically free theory in four dimensions. The importance of such a result would be twofold. First, the old question of the existence of QED could be settled. Of course, this would be the case provided that the low energy limit of the theory actually describes photons and electrons; apriori, there is no reason to assume this. Second, the discovery of a nontrivial nonasymptotically free theory would be of great paradigmatic value. The theories which quenched QED resembles the most are nonabelian gauge theories with many flavors with beta-function positive or vanishing at weak couplings. These theories are at present considered as viable candidates for technicolor unification schemes

  15. The Secret Driving Force Behind Mongolia’s Successful Democracy

    Science.gov (United States)

    2016-03-01

    the nation’s democracy movement its earliest stages. Courtesy of the Democratic Union of Mongolia PRISM 6, no. 1 FROM THE FIELD | 141 The Secret Driving...assistance and trade. Our state budget PRISM 6, no. 1 FROM THE FIELD | 143 THE SECRET DRIVING FORCE BEHIND MONGOLIA’S SUCCESSFUL DEMOCRACY collapsed; we...O yungerel Tsedevdam ba (2006) PRISM 6, no. 1 FROM THE FIELD | 145 THE SECRET DRIVING FORCE BEHIND MONGOLIA’S SUCCESSFUL DEMOCRACY significantly as

  16. Glenohumeral contact force during flat and topspin tennis forehand drives.

    Science.gov (United States)

    Blache, Yoann; Creveaux, Thomas; Dumas, Raphaël; Chèze, Laurence; Rogowski, Isabelle

    2017-03-01

    The primary role of the shoulder joint in tennis forehand drive is at the expense of the loadings undergone by this joint. Nevertheless, few studies investigated glenohumeral (GH) contact forces during forehand drives. The aim of this study was to investigate GH compressive and shearing forces during the flat and topspin forehand drives in advanced tennis players. 3D kinematics of flat and topspin forehand drives of 11 advanced tennis players were recorded. The Delft Shoulder and Elbow musculoskeletal model was implemented to assess the magnitude and orientation of GH contact forces during the forehand drives. The results showed no differences in magnitude and orientation of GH contact forces between the flat and topspin forehand drives. The estimated maximal GH contact force during the forward swing phase was 3573 ± 1383 N, which was on average 1.25 times greater than during the follow-through phase, and 5.8 times greater than during the backswing phase. Regardless the phase of the forehand drive, GH contact forces pointed towards the anterior-superior part of the glenoid therefore standing for shearing forces. Knowledge of GH contact forces during real sport tasks performed at high velocity may improve the understanding of various sport-specific adaptations and causative factors for shoulder problems.

  17. Entropic forces drive contraction of cytoskeletal networks

    Czech Academy of Sciences Publication Activity Database

    Braun, M.; Lánský, Zdeněk; Hilitski, F.; Dogic, Z.; Diez, S.

    2016-01-01

    Roč. 38, č. 5 (2016), s. 474-481 ISSN 0265-9247 R&D Projects: GA ČR(CZ) GA15-17488S; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:86652036 Keywords : cytoskeleton * depletion forces * entropic forces Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.441, year: 2016

  18. OSHA Laboratory Standard: Driving Force for Laboratory Safety!

    Science.gov (United States)

    Roy, Kenneth R.

    2000-01-01

    Discusses the Occupational Safety and Health Administration's (OSHA's) Laboratory Safety Standards as the major driving force in establishing and maintaining a safe working environment for teachers and students. (Author)

  19. Driving Force Filtering and Driving Mechanism Analysis of Urban Agricultural Development in Weifang County, China

    Directory of Open Access Journals (Sweden)

    SUI Fei-fei

    2016-03-01

    Full Text Available As an agricultural nation, the agricultural landscape is the basic appearance and existence in China, but the common existence often be neglected and contempted. As a new type of design and ideology, the development of urban agricultural landscape will greatly affect the texture and structure of the urban space. According to the urban agricultural production data and the socio-economic data of Weifang County, a set of evaluation index system that could analyze quantitatively the driving force of urban agricultural production changes and the internal drive mechanism was built. The original driving force indicators of economy, society, resources and environment from the time-series were chosen, and then 15 driving forces from the original driving forces by correlation analysis and principal component analysis were selected. The degree of influence was analyzed and the driving forces model by means of partial least squares(PLS was built. The results demonstrated that the factors greatly influenced the increase of urban agricultural output value in Weifang County were per capita net income of rural residents, agricultural machinery total power, effective irrigation area, centralized treatment rate of urban sewage, with the driving exponents 0.2509, 0.1019, 0.1655, 0.1332, respectively. The negative influence factor was the use amount of agricultural plastic film and the driving exponent was-0.2146. The research provides a reference for the development of urban agriculture, as well as a reference for the related study.

  20. The Driving Forces of Subsidiary Absorptive Capacity

    DEFF Research Database (Denmark)

    Schleimer, Stephanie C.; Pedersen, Torben

    2013-01-01

    The study investigates how a multinational corporation (MNC) can promote the absorptive capacity of its subsidiaries. The focus is on what drives the MNC subsidiary's ability to absorb marketing strategies that are initiated by the MNC parent, as well as how the subsidiary enacts on this absorptive...... as a purposeful response to this dual embeddedness. An analysis of marketing strategy absorptions undertaken by 213 subsidiaries reveals that MNCs can assist their subsidiaries to compete in competitive and dynamic focal markets by forming specific organizational mechanisms that are conducive to the development...

  1. Processes and driving forces in changing cultural landscapes across Europe

    DEFF Research Database (Denmark)

    Bürgi, Matthias; Bieling, Claudia; Von Hackwitz, Kim

    2017-01-01

    Context: Cultural landscapes evolve over time. However, the rate and direction of change might not be in line with societal needs and more information on the forces driving these changes are therefore needed. Objectives: Filling the gap between single case studies and meta-analyses, we present...... perceived landscape changes, and remembered driving forces. Land cover and landscape changes were analysed regarding change, conversions and processes. For all case study areas, narratives on mapped land cover change, perceived landscape changes and driving forces were compiled. Results: Despite a very high...... diversity in extent, direction and rates of change, a few dominant processes and widespread factors driving the changes could be identified in the six case study areas, i.e. access and infrastructure, political shifts, labor market, technological innovations, and for the more recent period climate change...

  2. A guide for statewide impaired-driving task forces.

    Science.gov (United States)

    2009-09-01

    The purpose of the guide is to assist State officials and other stakeholders who are interested in establishing an : Impaired-Driving Statewide Task Force or who are exploring ways to improve their current Task Force. The guide : addresses issues suc...

  3. Engaging Military Fathers in a Reflective Parenting Program: Lessons from Strong Families Strong Forces

    Science.gov (United States)

    DeVoe, Ellen R.; Paris, Ruth

    2015-01-01

    Through Strong Families Strong Forces, a reflective parenting program for military families with young children, we were privileged to work with contemporary military fathers who served in the post-9/11 conflicts in Afghanistan and Iraq. Due to this work, the authors gained valuable insight into the complexity of fathering during wartime, the…

  4. Orbital Forcing driving climate variability on Tropical South Atlantic

    Science.gov (United States)

    Oliveira, A. S.; Baker, P. A.; Silva, C. G.; Dwyer, G. S.; Chiessi, C. M.; Rigsby, C. A.; Ferreira, F.

    2017-12-01

    Past research on climate response to orbital forcing in tropical South America has emphasized on high precession cycles influencing low latitude hydrologic cycles, and driving the meridional migration of Intertropical Convergence Zone (ITCZ).However, marine proxy records from the tropical Pacific Ocean showed a strong 41-ka periodicities in Pleistocene seawater temperature and productivity related to fluctuations in Earth's obliquity. It Indicates that the western Pacific ITCZ migration was influenced by combined precession and obliquity changes. To reconstruct different climate regimes over the continent and understand the orbital cycle forcing over Tropical South America climate, hydrological reconstruction have been undertaken on sediment cores located on the Brazilian continental slope, representing the past 1.6 million years. Core CDH 79 site is located on a 2345 m deep seamount on the northern Brazilian continental slope (00° 39.6853' N, 44° 20.7723' W), 320 km from modern coastline of the Maranhão Gulf. High-resolution XRF analyses of Fe, Ti, K and Ca are used to define the changes in precipitation and sedimentary input history of Tropical South America. The response of the hydrology cycle to orbital forcing was studied using spectral analysis.The 1600 ka records of dry/wet conditions presented here indicates that orbital time-scale climate change has been a dominant feature of tropical climate. We conclude that the observed oscillation reflects variability in the ITCZ activity associated with the Earth's tilt. The prevalence of the eccentricity and obliquity signals in continental hydrology proxies (Ti/Ca and Fe/K) as implicated in our precipitation records, highlights that these orbital forcings play an important role in tropics hydrologic cycles. Throughout the Quaternary abrupt shifts of tropical variability are temporally correlated with abrupt climate changes and atmospheric reorganization during Mid-Pleistocene Transition and Mid-Brunhes Events

  5. Motive, desire, drive: the discourse of force

    Directory of Open Access Journals (Sweden)

    Alan Blum

    2013-12-01

    Full Text Available A review of the original paper on motive by Blum and McHugh (1971 is used as an occasion to make transparent an approach to social theory as it has developed over the years in their work. This method, in treating motive as an illustration, engages it as an example of the status of the signifier as a symptom of interpretive conflict endemic to any situation of action, always inviting an analysis of the symbolic order and imaginative structure that sustains the distinction as a force in social life. In this paper, motive in particular is unpacked to show how it serves as an indication of fundamental ambiguity with respect to a problem-solving situation, revealing in this case constant perplexity in relation to the enigmatic character of what comes to view on any occasion and the recurrent contestation that is released.

  6. Wall relaxation and the driving forces for cell expansive growth

    Science.gov (United States)

    Cosgrove, D. J.

    1987-01-01

    When water uptake by growing cells is prevented, the turgor pressure and the tensile stress in the cell wall are reduced by continued wall loosening. This process, termed in vivo stress relaxation, provides a new way to study the dynamics of wall loosening and to measure the wall yield threshold and the physiological wall extensibility. Stress relaxation experiments indicate that wall stress supplies the mechanical driving force for wall yielding. Cell expansion also requires water absorption. The driving force for water uptake during growth is created by wall relaxation, which lowers the water potential of the expanding cells. New techniques for measuring this driving force show that it is smaller than believed previously; in elongating stems it is only 0.3 to 0.5 bar. This means that the hydraulic resistance of the water transport pathway is small and that rate of cell expansion is controlled primarily by wall loosening and yielding.

  7. Sequential reconstruction of driving-forces from nonlinear nonstationary dynamics

    Science.gov (United States)

    Güntürkün, Ulaş

    2010-07-01

    This paper describes a functional analysis-based method for the estimation of driving-forces from nonlinear dynamic systems. The driving-forces account for the perturbation inputs induced by the external environment or the secular variations in the internal variables of the system. The proposed algorithm is applicable to the problems for which there is too little or no prior knowledge to build a rigorous mathematical model of the unknown dynamics. We derive the estimator conditioned on the differentiability of the unknown system’s mapping, and smoothness of the driving-force. The proposed algorithm is an adaptive sequential realization of the blind prediction error method, where the basic idea is to predict the observables, and retrieve the driving-force from the prediction error. Our realization of this idea is embodied by predicting the observables one-step into the future using a bank of echo state networks (ESN) in an online fashion, and then extracting the raw estimates from the prediction error and smoothing these estimates in two adaptive filtering stages. The adaptive nature of the algorithm enables to retrieve both slowly and rapidly varying driving-forces accurately, which are illustrated by simulations. Logistic and Moran-Ricker maps are studied in controlled experiments, exemplifying chaotic state and stochastic measurement models. The algorithm is also applied to the estimation of a driving-force from another nonlinear dynamic system that is stochastic in both state and measurement equations. The results are judged by the posterior Cramer-Rao lower bounds. The method is finally put into test on a real-world application; extracting sun’s magnetic flux from the sunspot time series.

  8. Generation of a strong core-centering force in a submillimeter compound droplet system

    International Nuclear Information System (INIS)

    Lee, M.C.; Feng, I.; Elleman, D.D.; Wang, T.G.; Young, A.T.

    1981-01-01

    By amplitude-modulating the driving voltage of an acoustic levitating apparatus, a strong core-centering force can be generated in a submillimeter compound droplet system suspended by the radiation pressure in a gaseous medium. Depending on the acoustic characteristics of the droplet system, it has been found that the technique can be utilized advantageously in the multiple-layer coating of an inertial-confinement-fusion pellet

  9. Driving reconnection in sheared magnetic configurations with forced fluctuations

    Science.gov (United States)

    Pongkitiwanichakul, Peera; Makwana, Kirit D.; Ruffolo, David

    2018-02-01

    We investigate reconnection of magnetic field lines in sheared magnetic field configurations due to fluctuations driven by random forcing by means of numerical simulations. The simulations are performed with an incompressible, pseudo-spectral magnetohydrodynamics code in 2D where we take thick, resistively decaying, current-sheet like sheared magnetic configurations which do not reconnect spontaneously. We describe and test the forcing that is introduced in the momentum equation to drive fluctuations. It is found that the forcing does not change the rate of decay; however, it adds and removes energy faster in the presence of the magnetic shear structure compared to when it has decayed away. We observe that such a forcing can induce magnetic reconnection due to field line wandering leading to the formation of magnetic islands and O-points. These reconnecting field lines spread out as the current sheet decays with time. A semi-empirical formula is derived which reasonably explains the formation and spread of O-points. We find that reconnection spreads faster with stronger forcing and longer correlation time of forcing, while the wavenumber of forcing does not have a significant effect. When the field line wandering becomes large enough, the neighboring current sheets with opposite polarity start interacting, and then the magnetic field is rapidly annihilated. This work is useful to understand how forced fluctuations can drive reconnection in large scale current structures in space and astrophysical plasmas that are not susceptible to reconnection.

  10. Petroleum Development in Russian Barents sea: Driving Forces and Constraints

    International Nuclear Information System (INIS)

    Moe, Arild; Joergensen, Anne-Kristin

    2000-01-01

    The potential of the Barents Sea for petroleum production has attracted interest for many years. In the Russian sector of this ocean, enormous gas finds and substantial oil resources have now been proven, and the first real licensing for field development in the area has just begun. Despite the area's potential, there are strong conflicts of interest. The report examines the forces alternatively driving and hindering offshore hydrocarbon development in the Russian sector of the Barents Sea. It describes exploration activities beginning during the Soviet period and extending to the present. The status of the major development projects financed in part with foreign capital, and conflicting regional and central government interests involved in such development, is described and evaluated. Coverage includes a discussion of the various regional interests in petroleum activities, with a particular focus on the conversion of naval yards in the area and the emergence of Rosshelf, an oil/gas conglomerate formed to facilitate such conversion. It also reviews the planned licensing rounds and the results of the first round. Finally, it discusses supplies from the Barents Sea in the context of overall Russian energy supply and energy development strategies. (author)

  11. Driving forces for texture transformation in thin Ag films

    International Nuclear Information System (INIS)

    Ellis, Elizabeth A.; Chmielus, Markus; Lin, Ming-Tzer; Joress, Howie; Visser, Kyle; Woll, Arthur; Vinci, Richard P.; Brown, Walter L.; Baker, Shefford P.

    2016-01-01

    The well-known thickness-dependent (111)-to-(100) texture transformation in thin FCC films is usually attributed to a competition between interface and strain energies. In this model, thin films retain their (111) texture due to the lower energy of the (111) interface, while thick films transform to (100) due to the lower stiffness and thus strain energy of a (100) film. However, recent work has called this model into question, suggesting that neither the stress nor the interface energy play a dominant role in texture transformation. We investigated the driving forces involved in this transformation by using a bulge test apparatus to induce different stresses in thin Ag films under identical annealing conditions. In situ synchrotron XRD measurements show the change in texture during annealing, and reveal that applied stresses have no effect on the transformation. Stress analysis shows that differences in driving forces for texture transformation due to applied bulge pressure were significant (≈200 kJ/m 3 ), suggesting that a different, much larger driving force must be responsible. Reduction in defect energy has been proposed as an alternative. However, vacancy and dislocation densities must be exceptionally high to significantly exceed the strain energy and do not provide obvious orientation selection mechanisms. Nanotwins in reported densities are shown to provide greater driving force (≈1000 kJ/m 3 ) and may account for orientation selection. The large difference between the calculated strain and defect energies and the driving force for grain growth (21,100 kJ/m 3 ) casts doubt on the applicability of a simple thermodynamic model of texture transformation.

  12. Drag force in a strongly coupled anisotropic plasma

    Science.gov (United States)

    Chernicoff, Mariano; Fernández, Daniel; Mateos, David; Trancanelli, Diego

    2012-08-01

    We calculate the drag force experienced by an infinitely massive quark propagating at constant velocity through an anisotropic, strongly coupled {N} = 4 plasma by means of its gravity dual. We find that the gluon cloud trailing behind the quark is generally misaligned with the quark velocity, and that the latter is also misaligned with the force. The drag coefficient μ can be larger or smaller than the corresponding isotropic value depending on the velocity and the direction of motion. In the ultra-relativistic limit we find that generically μ ∝ p. We discuss the conditions under which this behaviour may extend to more general situations.

  13. WP/084 Measuring Industry Agglomeration and Identifying the Driving Forces

    DEFF Research Database (Denmark)

    Howard, Emma; Tarp, Finn; Newman, Carol

    Understanding industry agglomeration and its driving forces is critical for the formulation of industrial policy in developing countries. Crucial to this process is the definition and measurement of agglomeration. We propose a new measure and examine what it reveals about the importance of transp......Understanding industry agglomeration and its driving forces is critical for the formulation of industrial policy in developing countries. Crucial to this process is the definition and measurement of agglomeration. We propose a new measure and examine what it reveals about the importance...... of transport costs, labour market pooling, and technology transfer for agglomeration processes. We contrast this analysis with insights from existing measures in the literature and find very different underlying stories at work. An exceptionally rich set of data from Vietnam makes us confident that our measure...

  14. Measuring Industry Coagglomeration and Identifying the Driving Forces

    DEFF Research Database (Denmark)

    Howard, Emma; Newman, Carol; Tarp, Finn

    2015-01-01

    Understanding industry agglomeration and its driving forces is critical for the formulation of industrial policy in developing countries. Crucial to this process is the definition and measurement of agglomeration. We construct a new coagglomeration index based purely on the location of firms. We...... underlying stories at work. We conclude that in conducting analyses of this kind giving consideration to the source of agglomeration economies, employees or entrepreneurs, and finding an appropriate measure for agglomeration, are both crucial to the process of identifying agglomerative forces....

  15. Forces that Drive Nanoscale Self-assembly on Solid Surfaces

    International Nuclear Information System (INIS)

    Suo, Z.; Lu, W.

    2000-01-01

    Experimental evidence has accumulated in the recent decade that nanoscale patterns can self-assemble on solid surfaces. A two-component monolayer grown on a solid surface may separate into distinct phases. Sometimes the phases select sizes about 10 nm, and order into an array of stripes or disks. This paper reviews a model that accounts for these behaviors. Attention is focused on thermodynamic forces that drive the self-assembly. A double-welled, composition-dependent free energy drives phase separation. The phase boundary energy drives phase coarsening. The concentration-dependent surface stress drives phase refining. It is the competition between the coarsening and the refining that leads to size selection and spatial ordering. These thermodynamic forces are embodied in a nonlinear diffusion equation. Numerical simulations reveal rich dynamics of the pattern formation process. It is relatively fast for the phases to separate and select a uniform size, but exceedingly slow to order over a long distance, unless the symmetry is suitably broken

  16. Drive frequency dependent phase imaging in piezoresponse force microscopy

    International Nuclear Information System (INIS)

    Bo Huifeng; Kan Yi; Lu Xiaomei; Liu Yunfei; Peng Song; Wang Xiaofei; Cai Wei; Xue Ruoshi; Zhu Jinsong

    2010-01-01

    The drive frequency dependent piezoresponse (PR) phase signal in near-stoichiometric lithium niobate crystals is studied by piezoresponse force microscopy. It is clearly shown that the local and nonlocal electrostatic forces have a great contribution to the PR phase signal. The significant PR phase difference of the antiparallel domains are observed at the contact resonances, which is related to the electrostatic dominated electromechanical interactions of the cantilever and tip-sample system. Moreover, the modulation voltage induced frequency shift at higher eigenmodes could be attributed to the change of indention force depending on the modulation amplitude with a piezoelectric origin. The PR phase of the silicon wafer is also measured for comparison. It is certificated that the electrostatic interactions are universal in voltage modulated scanning probe microscopy and could be extended to other phase imaging techniques.

  17. Production bias: A proposed modification of the driving force for void swelling under cascade damage conditions

    International Nuclear Information System (INIS)

    Woo, C.H.; Garner, F.A.

    1991-11-01

    A new concept of point-defect production as the main driving force for void swelling under cascade damage conditions is proposed. This concept takes into account the recombination and formation of immobile clusters and loops of vacancies and interstitials in the cascade region. The life times of the clusters and loops due to desolution are strong functions of the temperature, as well as their vacancy and interstitial nature. The resulting biased production of free point defects from the internal sources is shown to be a strong driving force for void swelling. The characteristics of void swelling due to production bias are described and compared with experimental results. We conclude that the production bias concept provides a good description of void swelling under cascade damage conditions

  18. Production bias: A proposed modification of the driving force for void swelling under cascade damage conditions

    International Nuclear Information System (INIS)

    Woo, C.H.; Singh, B.N.; Garner, F.A.

    1992-01-01

    A new concept of point defect production as the main driving force for void swelling under cascade damage conditions is proposed. This concept takes into account the recombination and formation of immobile clusters and loops of vacancies and interstitials in the cascade region. The lifetimes of the clusters and loops due to desolution are strong functions of the temperature, as well as their vacancy and interstitial nature. The resulting biased production of free point defects from the internal sources is shown to be a strong driving force for void swelling. The characteristics of void swelling due to production bias are described and compared with experimental results. We conclude that the production bias concept provides a good description of void swelling under cascade damage conditions. (orig.)

  19. 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

  20. Variation along liquid isomorphs of the driving force for crystallization

    DEFF Research Database (Denmark)

    Pedersen, Ulf Rørbæk; Adrjanowicz, Karolina; Niss, Kristine

    2017-01-01

    at a reference temperature. More general analysis allows interpretation of experimental data for molecular liquids such as dimethyl phthalate and indomethacin, and suggests that the isomorph scaling exponent γ in these cases is an increasing function of density, although this cannot be seen in measurements......We investigate the variation of the driving force for crystallization of a supercooled liquid along isomorphs, curves along which structure and dynamics are invariant. The variation is weak, and can be predicted accurately for the Lennard-Jones fluid using a recently developed formalism and data...

  1. A modified synthetic driving force method for molecular dynamics simulation of grain boundary migration

    International Nuclear Information System (INIS)

    Yang, Liang; Li, Saiyi

    2015-01-01

    The synthetic driving force (SDF) molecular dynamics method, which imposes crystalline orientation-dependent driving forces for grain boundary (GB) migration, has been considered deficient in many cases. In this work, we revealed the cause of the deficiency and proposed a modified method by introducing a new technique to distinguish atoms in grains and GB such that the driving forces can be imposed properly. This technique utilizes cross-reference order parameter (CROP) to characterize local lattice orientations in a bicrystal and introduces a CROP-based definition of interface region to minimize interference from thermal fluctuations in distinguishing atoms. A validation of the modified method was conducted by applying it to simulate the migration behavior of Ni 〈1 0 0〉 and Al 〈1 1 2〉 symmetrical tilt GBs, in comparison with the original method. The discrepancies between the migration velocities predicted by the two methods are found to be proportional to their differences in distinguishing atoms. For the Al 〈1 1 2〉 GBs, the modified method predicts a negative misorientation dependency for both the driving pressure threshold for initiating GB movement and the mobility, which agree with experimental findings and other molecular dynamics computations but contradict those predicted using the original method. Last, the modified method was applied to evaluate the mobility of Ni Σ5 〈1 0 0〉 symmetrical tilt GB under different driving pressure and temperature conditions. The results reveal a strong driving pressure dependency of the mobility at relatively low temperatures and suggest that the driving pressure should be as low as possible but large enough to trigger continuous migration.

  2. Spontaneous dressed-state polarization in the strong driving regime of cavity QED.

    Science.gov (United States)

    Armen, Michael A; Miller, Anthony E; Mabuchi, Hideo

    2009-10-23

    We utilize high-bandwidth phase-quadrature homodyne measurement of the light transmitted through a Fabry-Perot cavity, driven strongly and on resonance, to detect excess phase noise induced by a single intracavity atom. We analyze the correlation properties and driving-strength dependence of the atom-induced phase noise to establish that it corresponds to the long-predicted phenomenon of spontaneous dressed-state polarization. Our experiment thus provides a demonstration of cavity quantum electrodynamics in the strong-driving regime in which one atom interacts strongly with a many-photon cavity field to produce novel quantum stochastic behavior.

  3. Driving forces and barriers for environmental technology development

    International Nuclear Information System (INIS)

    2005-01-01

    Driving forces and barriers behind development and usage of environmental technology is discussed, and also whether there are certain characteristics related to environmental innovations compared to other innovations in general. The development of environmental technology is in principle dominated by the same drivers and barriers as any other technology, but the order and strength of the various factors may be different. This examination as well as other empirical studies shows that regulations play a greater part for environmental technology than 'pure market forces'. To many participants it is important to be one step ahead of the regulations, i.e. the expected regulations are equally important as the factual ones in driving the technology development. Players in the business community express that it is important that the authorities cooperate with them when introducing new regulations. This will increase acceptance for the regulations and facilitate the necessary adjustments. The most important barrier in the development and use of the technologies studied is probably the lack of demand

  4. Segregation in ternary alloys: an interplay of driving forces

    International Nuclear Information System (INIS)

    Luyten, J.; Helfensteyn, S.; Creemers, C.

    2003-01-01

    Monte Carlo (MC) simulations combined with the constant bond energy (CBE) model are set up to explore and understand the general segregation behaviour in ternary alloys as a function of composition and more in particular the segregation to Cu-Ni-Al (1 0 0) surfaces. Besides its simplicity, allowing swift simulations, which are necessary for a first general survey over all possible compositions, one of the advantages of the CBE model lies in the possibility to clearly identify the different driving forces for segregation. All simulations are performed in the Grand Canonical Ensemble, using a new algorithm to determine the chemical potential of the components. Notwithstanding the simplicity of the CBE model, one extra feature is evidenced: depending on the values of the interatomic interaction parameters, in some regions of the ternary diagram, a single solid solution becomes thermodynamically unstable, leading to demixing into two conjugate phases. The simulations are first done for three hypothetical systems that are however representative for real alloy systems. The three systems are characterised by different sets of interatomic interaction parameters. These extensive simulations over the entire composition range of the ternary alloy yield a 'topographical' segregation map, showing distinct regions where different species segregate. These distinct domains originate from a variable interplay between the driving forces for segregation and attractive/repulsive interactions in the bulk of the alloy. The results on these hypothetical systems are very helpful for a better understanding of the segregation behaviour in Cu-Ni-Al and other ternary alloys

  5. Driving force for hydrophobic interaction at different length scales.

    Science.gov (United States)

    Zangi, Ronen

    2011-03-17

    We study by molecular dynamics simulations the driving force for the hydrophobic interaction between graphene sheets of different sizes down to the atomic scale. Similar to the prediction by Lum, Chandler, and Weeks for hard-sphere solvation [J. Phys. Chem. B 1999, 103, 4570-4577], we find the driving force to be length-scale dependent, despite the fact that our model systems do not exhibit dewetting. For small hydrophobic solutes, the association is purely entropic, while enthalpy favors dissociation. The latter is demonstrated to arise from the enhancement of hydrogen bonding between the water molecules around small hydrophobes. On the other hand, the attraction between large graphene sheets is dominated by enthalpy which mainly originates from direct solute-solute interactions. The crossover length is found to be inside the range of 0.3-1.5 nm(2) of the surface area of the hydrophobe that is eliminated in the association process. In the large-scale regime, different thermodynamic properties are scalable with this change of surface area. In particular, upon dimerization, a total and a water-induced stabilization of approximately 65 and 12 kJ/mol/nm(2) are obtained, respectively, and on average around one hydrogen bond is gained per 1 nm(2) of graphene sheet association. Furthermore, the potential of mean force between the sheets is also scalable except for interplate distances smaller than 0.64 nm which corresponds to the region around the barrier for removing the last layer of water. It turns out that, as the surface area increases, the relative height of the barrier for association decreases and the range of attraction increases. It is also shown that, around small hydrophobic solutes, the lifetime of the hydrogen bonds is longer than in the bulk, while around large hydrophobes it is the same. Nevertheless, the rearrangement of the hydrogen-bond network for both length-scale regimes is slower than in bulk water. © 2011 American Chemical Society

  6. The driving forces of landscape change in Europe

    DEFF Research Database (Denmark)

    Plieninger, Tobias; Draux, Hélène; Fagerholm, Nora

    2016-01-01

    , we find that distinct combinations of mainly political/institutional, cultural, and natural/spatial underlying drivers are determining landscape change, rather than single key drivers. Our systematic review indicates knowledge gaps that can be filled by: (a) expanding the scope of studies to include...... because landscape research is spread across many domains and disciplines. We here provide a systematic synthesis of 144 studies that identify the proximate and underlying drivers of landscape change across Europe. First, we categorize how driving forces have been addressed and find that most studies......; low Gross Domestic Product; boreal, steppic, and arctic landscapes; as well as forestland systems are underrepresented in the literature. Third, our review shows that land abandonment/extensification is the most prominent (62% of cases) among multiple proximate drivers of landscape change. Fourthly...

  7. Discharge switch driving by Lorentz force and its characteristics

    International Nuclear Information System (INIS)

    Inoue, Kunikazu; Hasegawa, Mitsuo; Ueno, Isao

    1999-01-01

    Our newly developed 'Rotary-Arc mode Discharge Switch' have featured longer life expectancy and lower inductance-wise by extremely minimizing the insulation deterioration and consumable main electrode through installation of permanent magnet, simplified construction and careful attention on the demagnetization. Resultantly, highly efficient and larger capacitive discharge switch have been available at such economical cost. In addition, by having derived an experimental formula for the driving speed of the arc, the required design parameters of the discharge switch have been determined, and then it has been well noted that any affections of electro-magnetic Lorentz force toward the starting characteristics have been negligible small. All these have made it possible to materialize such discharge switch which will satisfy the required conditions. (author)

  8. Testing thermal gradient driving force for grain boundary migration using molecular dynamics simulations

    International Nuclear Information System (INIS)

    Bai, Xian-Ming; Zhang, Yongfeng; Tonks, Michael R.

    2015-01-01

    Strong thermal gradients in low-thermal-conductivity ceramics may drive extended defects, such as grain boundaries and voids, to migrate in preferential directions. In this work, molecular dynamics simulations are conducted to study thermal gradient driven grain boundary migration and to verify a previously proposed thermal gradient driving force equation, using uranium dioxide as a model system. It is found that a thermal gradient drives grain boundaries to migrate up the gradient and the migration velocity increases under a constant gradient owing to the increase in mobility with temperature. Different grain boundaries migrate at very different rates due to their different intrinsic mobilities. The extracted mobilities from the thermal gradient driven simulations are compared with those calculated from two other well-established methods and good agreement between the three different methods is found, demonstrating that the theoretical equation of the thermal gradient driving force is valid, although a correction of one input parameter should be made. The discrepancy in the grain boundary mobilities between modeling and experiments is also discussed.

  9. Mixing Characteristics of Strongly-Forced Jet Flames in Crossflow

    Science.gov (United States)

    Marr, Kevin; Clemens, Noel; Ezekoye, Ofodike

    2008-11-01

    The effects of high frequency, large-amplitude forcing on the characteristics of a non-premixed jet flame in crossflow (JFICF) at mean Reynolds numbers of 3,200 and 4,850 are studied experimentally. Harmonic forcing of the jet fuel results in a drastic decrease in flame length and complete suppression of soot luminosity. Visualization by planar laser Mie scattering shows that forced JFICF, similar to forced free or coflow jet flames, are characterized by ejection of high-momentum, deeply penetrating vortical structures. These structures rapidly breakdown and promote intense turbulent mixing in the near region of the jet. The rapid mixing resembles a ``one-step'' process going from a fuel rich state far in the nozzle to a well-mixed, but significantly diluted, state just a few diameters from the jet exit plane. Exhaust gas emissions measurements indicate a decrease in NOx, but increases in CO and unburned hydrocarbons with increasing forcing amplitude. Acetone PLIF measurements are used to investigate the effect of partial-premixing on these emissions findings.

  10. Probabilistic analysis for identifying the driving force of protein folding

    Science.gov (United States)

    Tokunaga, Yoshihiko; Yamamori, Yu; Matubayasi, Nobuyuki

    2018-03-01

    Toward identifying the driving force of protein folding, energetics was analyzed in water for Trp-cage (20 residues), protein G (56 residues), and ubiquitin (76 residues) at their native (folded) and heat-denatured (unfolded) states. All-atom molecular dynamics simulation was conducted, and the hydration effect was quantified by the solvation free energy. The free-energy calculation was done by employing the solution theory in the energy representation, and it was seen that the sum of the protein intramolecular (structural) energy and the solvation free energy is more favorable for a folded structure than for an unfolded one generated by heat. Probabilistic arguments were then developed to determine which of the electrostatic, van der Waals, and excluded-volume components of the interactions in the protein-water system governs the relative stabilities between the folded and unfolded structures. It was found that the electrostatic interaction does not correspond to the preference order of the two structures. The van der Waals and excluded-volume components were shown, on the other hand, to provide the right order of preference at probabilities of almost unity, and it is argued that a useful modeling of protein folding is possible on the basis of the excluded-volume effect.

  11. Gravity and strong force: potentially linked by Quantum Wormholes

    International Nuclear Information System (INIS)

    Goradia, Sh.G.

    2004-01-01

    If Newtonian gravitation is modified to use surface-to-surface separation between particles, can have the strength of nuclear force between nucleons. This may be justified by possible existence of quantum wormholes in particles. All gravitational interactions would be between coupled wormholes, emitting graviton flux in proportional to particle size, allowing for the point-like treatment above. When le wormholes are 1 Planck length apart, the resultant force is 10 40 times the normal gravitational strength for nucleons. Additionally, the invisible quantum wormholes may form binary effects imparting we properties to all particles

  12. Unconventional geometric logic gate in a strong-driving-assisted multi-mode cavity

    International Nuclear Information System (INIS)

    Chang-Ning, Pan; Di-Wu, Yang; Xue-Hui, Zhao; Mao-Fa, Fang

    2010-01-01

    We propose a scheme to implement an unconventional geometric logic gate separately in a two-mode cavity and a multi-mode cavity assisted by a strong classical driving field. The effect of the cavity decay is included in the investigation. The numerical calculation is carried out, and the result shows that our scheme is more tolerant to cavity decay than the previous one because the time consumed for finishing the logic gate is doubly reduced. (general)

  13. Small and Medium Sized Reactors: Driving Forces and Technology Development

    International Nuclear Information System (INIS)

    Gowin, P.J.; Kupitz, J.

    2002-01-01

    There will be growing demands for energy in the coming decades. One aspect of particular importance is that prospects for nuclear energy will to a considerable extent be influenced by developing countries. Since population growth will occur primarily in developing countries nuclear energy cannot play a significant global role without being a viable option in these countries. Since new power plants to be built will have to be compatible with regional electricity grids, this may result in a greater focus on plants in the small and medium range, defined by the International Atomic Energy Agency (IAEA) to produce up to 700 Megawatt of electrical power. This paper first examines the driving forces that could influence the development of nuclear energy in general and of Small and Medium Sized Reactors (SMRs) in particular in the next decades and identifies key factors in that process. Concerns over climate change may to a certain extent influence the discussion on future energy options. Other factors of equal importance for the future of nuclear are a continued emphasis on maintaining high safety standards, the implementation of acceptable solutions for spent fuel and radioactive waste disposal and a globally accepted non-proliferation regime, factors that may in turn have an impact on public acceptance. Economic competitiveness of nuclear energy is an additional important factor, and without being commercially viable, no energy source can in the long run represent a major and stable component in a competitive energy sector. The introduction of SMRs in developing countries poses additional challenges, such as investment limitations. Technology development plays an important role in keeping the nuclear option open for countries wishing to use nuclear reactors to meet their energy needs, and advances in reactor design will be important to enable a significant nuclear component in developing countries. This paper considers the contribution that nuclear science and

  14. Autoimmunity as a Driving Force of Cognitive Evolution

    Directory of Open Access Journals (Sweden)

    Serge Nataf

    2017-10-01

    Full Text Available In the last decades, increasingly robust experimental approaches have formally demonstrated that autoimmunity is a physiological process involved in a large range of functions including cognition. On this basis, the recently enunciated “brain superautoantigens” theory proposes that autoimmunity has been a driving force of cognitive evolution. It is notably suggested that the immune and nervous systems have somehow co-evolved and exerted a mutual selection pressure benefiting to both systems. In this two-way process, the evolutionary-determined emergence of neurons expressing specific immunogenic antigens (brain superautoantigens has exerted a selection pressure on immune genes shaping the T-cell repertoire. Such a selection pressure on immune genes has translated into the emergence of a finely tuned autoimmune T-cell repertoire that promotes cognition. In another hand, the evolutionary-determined emergence of brain-autoreactive T-cells has exerted a selection pressure on neural genes coding for brain superautoantigens. Such a selection pressure has translated into the emergence of a neural repertoire (defined here as the whole of neurons, synapses and non-neuronal cells involved in cognitive functions expressing brain superautoantigens. Overall, the brain superautoantigens theory suggests that cognitive evolution might have been primarily driven by internal cues rather than external environmental conditions. Importantly, while providing a unique molecular connection between neural and T-cell repertoires under physiological conditions, brain superautoantigens may also constitute an Achilles heel responsible for the particular susceptibility of Homo sapiens to “neuroimmune co-pathologies” i.e., disorders affecting both neural and T-cell repertoires. These may notably include paraneoplastic syndromes, multiple sclerosis as well as autism, schizophrenia and neurodegenerative diseases. In the context of this theoretical frame, a specific

  15. A balanced ATP driving force module for enhancing photosynthetic biosynthesis of 3-hydroxybutyrate from CO2.

    Science.gov (United States)

    Ku, Jason T; Lan, Ethan I

    2018-03-01

    Using engineered photoautotrophic microorganisms for the direct chemical synthesis from CO 2 is an attractive direction for both sustainability and CO 2 mitigation. However, the behaviors of non-native metabolic pathways may be difficult to control due to the different intracellular contexts between natural and heterologous hosts. While most metabolic engineering efforts focus on strengthening driving forces in pathway design to favor biochemical production in these organisms, excessive driving force may be detrimental to product biosynthesis due to imbalanced cellular intermediate distribution. In this study, an ATP-hydrolysis based driving force module was engineered into cyanobacterium Synechococcus elongatus PCC 7942 to produce 3-hydroxybutyrate (3HB), a valuable chemical feedstock for the synthesis of biodegradable plastics and antibiotics. However, while the ATP driving force module is effective for increasing product formation, uncontrolled accumulation of intermediate metabolites likely led to metabolic imbalance and thus to cell growth inhibition. Therefore, the ATP driving force module was reengineered by providing a reversible outlet for excessive carbon flux. Upon expression of this balanced ATP driving force module with 3HB biosynthesis, engineered strain produced 3HB with a cumulative titer of 1.2 g/L, a significant increase over the initial strain. This result highlighted the importance of pathway reversibility as an effective design strategy for balancing driving force and intermediate accumulation, thereby achieving a self-regulated control for increased net flux towards product biosynthesis. Copyright © 2018 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  16. Effect of a powered drive on pushing and pulling forces when transporting bariatric hospital beds.

    Science.gov (United States)

    Wiggermann, Neal

    2017-01-01

    Powered drives designed to assist with moving hospital beds are commercially available but no studies have evaluated whether they reduce the push and pull forces likely contributing to injury in caregivers. This study measured hand forces of 10 caregivers maneuvering a manual and powered bariatric bed through simulated hospital environments (hallway, elevator, and ramp). Peak push and pull forces exceeded previously established psychophysical limits for all activities with the manual bed. For the powered bed, peak forces were significantly (p pushing did not differ between beds. Powered drive may reduce the risk of injury or the number of caregivers needed for transport. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Driving forces for adsorption of amphiphilic peptides to the air-water interface.

    Science.gov (United States)

    Engin, Ozge; Villa, Alessandra; Sayar, Mehmet; Hess, Berk

    2010-09-02

    We have studied the partitioning of amphiphilic peptides at the air-water interface. The free energy of adsorption from bulk to interface was calculated by determining the potential of mean force via atomistic molecular dynamics simulations. To this end a method is introduced to restrain or constrain the center of mass of a group of molecules in a periodic system. The model amphiphilic peptides are composed of alternating valine and asparagine residues. The decomposition of the free energy difference between the bulk and interface is studied for different peptide block lengths. Our analysis revealed that for short amphiphilic peptides the surface driving force dominantly stems from the dehydration of hydrophobic side chains. The only opposing force is associated with the loss of orientational freedom of the peptide at the interface. For the peptides studied, the free energy difference scales linearly with the size of the molecule, since the peptides mainly adopt extended conformations both in bulk and at the interface. The free energy difference depends strongly on the water model, which can be rationalized through the hydration thermodynamics of hydrophobic solutes. Finally, we measured the reduction of the surface tension associated with complete coverage of the interface with peptides.

  18. Social Innovation : Driving Forces of Social Innovation in MNC

    OpenAIRE

    Tam, Hoising; Osadcha, Liudmyla

    2017-01-01

    Multinational Corporations (MNCs) currently face not only a dynamic business environment and challenging profit target, but also increased expectations from the public to take responsibility for addressing social, economic, and environmental issues. There is a tendency that the leading companies in the global market, especially MNCs, put more effort to the Social Innovation (SI). This study is to investigate what drives the MNCs to be involved in social innovation. In order to find out the re...

  19. Remark on the role of the driving force in BWR instability

    International Nuclear Information System (INIS)

    Dykin, V.; Pazsit, I.

    2009-01-01

    Simple models of BWR instability, used e.g. in understanding the role of the various oscillation modes in the overall stability of the plant, assume that each oscillation mode can be described by a second order system (a damped harmonic oscillator) driven by a white noise driving force. Change of the decay ratio (DR) of the observed signal is, as a rule, associated with the changing of the parameters of the damped oscillator, mainly its damping coefficient, and is interpreted in terms of the change of the stability of the system. However, conceptually, one cannot exclude cases when the change of the response of a driven damped oscillator is due to the change of the properties of the driving force. In this work we investigate the effect of a non-white driving force on the behaviour of the system. A question of interest is how changes of the spectrum of the driving force influence the observed autocorrelation function (ACF) of the resulting signal. Hence we calculate the response of a damped harmonic oscillator driven by a non-white driving force, corresponding to the reactivity effect of propagating density fluctuations in two-phase flow. It is shown how in some special cases such a driving force, when interpreting the neutron noise as if induced by a white noise driving source, can lead to an erroneous conclusion regarding the stability of the system. It is also concluded that in the practically interesting cases the effect of the coloured driving force, arising from propagating density fluctuations, is negligible.

  20. Boomers and seniors: The driving force behind leisure participation

    Science.gov (United States)

    Lynda J. Sperazza; Priya Banerjee

    2010-01-01

    The 76 million Americans in the Baby Boomer population are the force behind the changing demographic picture of society today. Boomers' spending habits and lifestyle choices will also have a powerful influence on retirement and leisure in the coming decades. Boomers will redefine retirement and are expected to demand more than current senior programs and...

  1. An introductory handbook for state task forces to combat drunk driving.

    Science.gov (United States)

    1983-01-01

    In June 1982 Governor Robb created a task force to identify and assess efforts under way in Virginia to address the problem of drunken driving and to make recommendations. This booklet was prepared to assist the task force in its deliberations.

  2. COMPETITIVENESS IN SERVICES, DRIVING FORCE OF ECONOMIC DEVELOPMENT

    OpenAIRE

    RAMONA PÎRVU; MARIA DANATIE ENESCU

    2012-01-01

    The competitiveness of a nation is ensured by the profitable activity of firms. They strengthen their position in the domestic and international markets through global strategies whose purpose is to increase productivity and maintain it at a high level. For this, the company must take into account both the internal economic environment which ensures operating conditions and the external economic environment’s development. The five competitive forces determine the industry’s profitability beca...

  3. Increased rate of acceleration on Pine Island Glacier strongly coupled to changes in gravitational driving stress

    Directory of Open Access Journals (Sweden)

    J. B. T. Scott

    2009-05-01

    Full Text Available Pine Island Glacier, Antarctica, has been undergoing several related changes for at least two decades; these include acceleration, thinning and grounding line retreat. During the first major ground-based study between 2006 and 2008, GPS receivers were used to monitor ice flow from 55 km to 171 km inland, along the central flowline. At four sites both acceleration and thinning rates over the last two years exceeded rates observed at any other time over the last two decades. At the downstream site acceleration was 6.4% over 2007 and thinning was 3.5±0.5 ma−1. Acceleration and thinning have spread rapidly inland with the acceleration 171 km inland at 4.1% over 2007, greater than any measured annual flow increase along the whole glacier prior to 2006. Increases in surface slope, and hence gravitational driving stress, correlate well with the acceleration and no sustained change in longitudinal stress gradient is needed to explain the force balance. There is no indication that the glacier is approaching a new steady state.

  4. Position and force control of a vehicle with two or more steerable drive wheels

    Energy Technology Data Exchange (ETDEWEB)

    Reister, D.B.; Unseren, M.A.

    1992-10-01

    When a vehicle with two or more steerable drive wheels is traveling in a circle, the motion of the wheels is constrained. The wheel translational velocity divided by the radius to the center of rotation must be the same for all wheels. When the drive wheels are controlled independently using position control, the motion of the wheels may violate the constraints and the wheels may slip. Consequently, substantial errors can occur in the orientation of the vehicle. A vehicle with N drive wheels has (N - 1) constraints and one degree of freedom. We have developed a new approach to the control of a vehicle with N steerable drive wheels. The novel aspect of our approach is the use of force control. To control the vehicle, we have one degree of freedom for the position on the circle and (N - 1) forces that can be used to reduce errors. Recently, Kankaanranta and Koivo developed a control architecture that allows the force and position degrees of freedom to be decoupled. In the work of Kankaanranta and Koivo the force is an exogenous input. We have made the force endogenous by defining the force in terms of the errors in satisfying the rigid body kinematic constraints. We have applied the control architecture to the HERMIES-III robot and have measured a dramatic reduction in error (more than a factor of 20) compared to motions without force control.

  5. Intensification of grassland and forage use: driving forces and constraints

    NARCIS (Netherlands)

    Oenema, O.; Klein, de C.; Alfaro, M.

    2014-01-01

    The increasing demand for safe and nutritional dairy and beef products in a globalising world, together with the needs to increase resource use efficiency and to protect biodiversity, provide strong incentives for intensification of grassland and forage use. This paper addresses the question: 'Does

  6. Gravity: one of the driving forces for evolution.

    Science.gov (United States)

    Volkmann, D; Baluska, F

    2006-12-01

    Mechanical load is 10(3) larger for land-living than for water-living organisms. As a consequence, antigravitational material in form of compound materials like lignified cell walls in plants and mineralised bones in animals occurs in land-living organisms preferentially. Besides cellulose, pectic substances of plant cell walls seem to function as antigravitational material in early phases of plant evolution and development. A testable hypothesis including vesicular recycling processes into the tensegrity concept is proposed for both sensing of gravitational force and responding by production of antigravitational material at the cellular level.

  7. Crack Driving Forces in a Multilayered Coating System for Ceramic Matrix Composite Substrates

    Science.gov (United States)

    Ghosn, Louis J.; Zhu, Dongming; Miller, Robert A.

    2005-01-01

    The effects of the top coating thickness, modulus and shrinkage strains on the crack driving forces for a baseline multilayer Yttria-Stabilized-Zirconia/Mullite/Si thermal and environment barrier coating (TEBC) system for SiC/SiC ceramic matrix composite substrates are determined for gas turbine applications. The crack driving forces increase with increasing modulus, and a low modulus thermal barrier coating material (below 10 GPa) will have no cracking issues under the thermal gradient condition analyzed. Since top coating sintering increases the crack driving forces with time, highly sintering resistant coatings are desirable to maintain a low tensile modulus and maintain a low crack driving force with time. Finite element results demonstrated that an advanced TEBC system, such as ZrO2/HfO2, which possesses improved sintering resistance and high temperature stability, exhibited excellent durability. A multi-vertical cracked structure with fine columnar spacing is an ideal strain tolerant coating capable of reducing the crack driving forces to an acceptable level even with a high modulus of 50 GPa.

  8. Evaluating the Energetic Driving Force for Cocrystal Formation.

    Science.gov (United States)

    Taylor, Christopher R; Day, Graeme M

    2018-02-07

    We present a periodic density functional theory study of the stability of 350 organic cocrystals relative to their pure single-component structures, the largest study of cocrystals yet performed with high-level computational methods. Our calculations demonstrate that cocrystals are on average 8 kJ mol -1 more stable than their constituent single-component structures and are very rarely (intuition, the presence of hydrogen or halogen bond interactions is not necessarily a good predictor of stability. Finally, we investigate the correlation of the relative stability with simple chemical descriptors: changes in packing efficiency and hydrogen bond strength. We find some broad qualitative agreement with chemical intuition-more densely packed cocrystals with stronger hydrogen bonding tend to be more stable-but the relationship is weak, suggesting that such simple descriptors do not capture the complex balance of interactions driving cocrystallization. Our conclusions suggest that while cocrystallization is often a thermodynamically favorable process, it remains difficult to formulate general rules to guide synthesis, highlighting the continued importance of high-level computation in predicting and rationalizing such systems.

  9. Solar Radiation as Driving Force In Early Evolution

    Science.gov (United States)

    Rothschild, Lynn J.; Peterson, David L. (Technical Monitor)

    2002-01-01

    Ultraviolet radiation (UVR) has provided an evolutionary challenge to life on Earth in that it is both an agent of mutation and as well as a selective force. Today surface fluxes of UVR vary diurnally, seasonally, etc. Still, the UVR flux was probably substantially higher during the early phases of evolution, suggesting that its role in evolution was even more prominent during this time. In this presentation, the creative role of UVR in evolution is discussed, specifically in connection with the role that UVR may have played in the evolution of early microbial ecosystems. The presentation will include discussions of the direct influence of UVR on such processes as photosynthesis and genetic damage, as well as the indirect influence of UVR as mediated through the production of reactive oxygen species. These biological effects of UVR will be viewed against the backdrop of the physical nature of the early Earth, surely a very different place then than now.

  10. Delegation to automaticity: the driving force for cognitive evolution?

    Science.gov (United States)

    Shine, J M; Shine, R

    2014-01-01

    The ability to delegate control over repetitive tasks from higher to lower neural centers may be a fundamental innovation in human cognition. Plausibly, the massive neurocomputational challenges associated with the mastery of balance during the evolution of bipedality in proto-humans provided a strong selective advantage to individuals with brains capable of efficiently transferring tasks in this way. Thus, the shift from quadrupedal to bipedal locomotion may have driven the rapid evolution of distinctive features of human neuronal functioning. We review recent studies of functional neuroanatomy that bear upon this hypothesis, and identify ways to test our ideas.

  11. Hypoxia: The Force that Drives Chronic Kidney Disease

    Science.gov (United States)

    Fu, Qiangwei; Colgan, Sean P; Shelley, Carl Simon

    2016-01-01

    In the United States the prevalence of end-stage renal disease (ESRD) reached epidemic proportions in 2012 with over 600,000 patients being treated. The rates of ESRD among the elderly are disproportionally high. Consequently, as life expectancy increases and the baby-boom generation reaches retirement age, the already heavy burden imposed by ESRD on the US health care system is set to increase dramatically. ESRD represents the terminal stage of chronic kidney disease (CKD). A large body of evidence indicating that CKD is driven by renal tissue hypoxia has led to the development of therapeutic strategies that increase kidney oxygenation and the contention that chronic hypoxia is the final common pathway to end-stage renal failure. Numerous studies have demonstrated that one of the most potent means by which hypoxic conditions within the kidney produce CKD is by inducing a sustained inflammatory attack by infiltrating leukocytes. Indispensable to this attack is the acquisition by leukocytes of an adhesive phenotype. It was thought that this process resulted exclusively from leukocytes responding to cytokines released from ischemic renal endothelium. However, recently it has been demonstrated that leukocytes also become activated independent of the hypoxic response of endothelial cells. It was found that this endothelium-independent mechanism involves leukocytes directly sensing hypoxia and responding by transcriptional induction of the genes that encode the β2-integrin family of adhesion molecules. This induction likely maintains the long-term inflammation by which hypoxia drives the pathogenesis of CKD. Consequently, targeting these transcriptional mechanisms would appear to represent a promising new therapeutic strategy. PMID:26847481

  12. Information driving force and its application in agent-based modeling

    Science.gov (United States)

    Chen, Ting-Ting; Zheng, Bo; Li, Yan; Jiang, Xiong-Fei

    2018-04-01

    Exploring the scientific impact of online big-data has attracted much attention of researchers from different fields in recent years. Complex financial systems are typical open systems profoundly influenced by the external information. Based on the large-scale data in the public media and stock markets, we first define an information driving force, and analyze how it affects the complex financial system. The information driving force is observed to be asymmetric in the bull and bear market states. As an application, we then propose an agent-based model driven by the information driving force. Especially, all the key parameters are determined from the empirical analysis rather than from statistical fitting of the simulation results. With our model, both the stationary properties and non-stationary dynamic behaviors are simulated. Considering the mean-field effect of the external information, we also propose a few-body model to simulate the financial market in the laboratory.

  13. COMPETITIVENESS IN SERVICES, DRIVING FORCE OF ECONOMIC DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    RAMONA PÎRVU

    2012-12-01

    Full Text Available The competitiveness of a nation is ensured by the profitable activity of firms. They strengthen their position in the domestic and international markets through global strategies whose purpose is to increase productivity and maintain it at a high level. For this, the company must take into account both the internal economic environment which ensures operating conditions and the external economic environment’s development. The five competitive forces determine the industry’s profitability because they configure firms’ selling prices, production costs and investments needed to be competitive in the field. The threat of new competitors limits the potential profit since they involve new production units and the opportunities for market expansion. Economic strength of the buyers and bidders attracts profits to them. Rivalry among existing competitors erodes profits by increasing costs of competition (like advertising, selling expenses or those required for research and development. The presence of substitutive goods or services limits competitors’ prices through buyers’ transfer phenomena limiting and eroding market share of industry / firm in the total production output.

  14. On Optimizing Steering Performance of Multi-axle Vehicle Based on Driving Force Control

    Directory of Open Access Journals (Sweden)

    Wu Zhicheng

    2017-01-01

    Full Text Available The steering performance of multi-axle vehicle with independent driving system is affected by the distribution of the wheel driving force. A nonlinear vehicle dynamics model including magic formula tire model for describing 11 DoF four-axle vehicle with dual-front-axle-steering (DFAS system was presented. The influence of different driving force distribution scheme on the steering performance of the vehicle was analyzed. A control strategy for improving the steady response and transient response of the vehicle steering is proposed. The results show: For the steady response, setting different drive force for internal and external wheels according to the actual steering characteristics of the vehicle can effectively improve its steering characteristics; For the transient response, adopting the zero sideslip angle control strategy and using the PID control algorithm to control the driving force of the outside wheel of tear-two-axle, under angle step input, the vehicle sideslip angle can quickly stabilize to 0 and yaw rate also significantly decreases.

  15. Gauge unification of basic forces particularly of gravitation with strong interactions

    International Nuclear Information System (INIS)

    Salam, A.

    1977-01-01

    Corresponding to the two known types of gauge theories, Yang-Mills with spin-one mediating particles and Einstein Weyl with spin-two mediating particles, it is speculated that two distinct gauge unifications of the basic forces appear to be taking place. One is the familiar Yang-Mills unification of weak and electromagnetic forces with the strong. The second is the less familiar gauge unification of gravitation with spin-two tensor-dominated aspects of strong interactions. It is proposed that there are strongly interacting spin-two strong gravitons obeying Einstein's equations, and their existence gives a clue to an understanding of the (partial) confinement of quarks, as well as of the concept of hadronic temperature, through the use of Schwarzschild de-Sitter-like partially confining solitonic solutions of the strong gravity Einstein equation

  16. Preliminary Experimental Results for Indirect Vector-Control of Induction Motor Drives with Forced Dynamics

    Directory of Open Access Journals (Sweden)

    Jan Vittek

    2003-01-01

    Full Text Available The contribution presents an extension of indirect vector control of electric drives employing induction motors to 'Forced Dynamic Control'. This method of control offers an accurate realisation of dynamic response profiles, which can be selected by the user. The developed system can be integrated into a drive with a shaft position encoder or a shaft sensoriess drive, in which only the stator currents are measured. The applied stator voltages are determined by a computed inverter switching algorithm. Simulation results and preliminary experimental results for indirect vector control of an idle running induction motor indicate good agreement with the theoretical predictions.

  17. Development of an innovative reflector drive mechanism using magnetic repulsion force for 4S reactor

    International Nuclear Information System (INIS)

    Tsuji, K.; Watanabe, M.; Inagaki, H.; Nishikawa, A.; Takahashi, H.; Wakamatsu, M.; Matsumiya, H.; Nishiguchi, Y.

    2001-01-01

    A small sized fast reactor 4S: (Super Safe Small and Simple) which has a core of 10 - 30 years life time is controlled by reflectors. The reflector is required to be risen at very low speed to make up for the reactivity swing during operation. This report shows the development of an innovative reflector drive mechanism using magnetic repulsion force that can move at a several micrometer per one step. This drive mechanism has a passive shut down capability, and can eliminate reflector drive line. (author)

  18. Study on electromagnetism force of CARR control rod drive mechanism experimental machine

    International Nuclear Information System (INIS)

    Zhu Xuewei; Zhen Jianxiao; Wang Yulin; Jia Yueguang; Yang Kun; Yin Haozhe

    2015-01-01

    With the aim of acquiring electromagnetic force and electromagnetic field distributions of control rod drive mechanism (CRDM) in China Advanced Research Reactor (CARR), the force analysis on the CRDM was taken. Manufacturing the experimental machine, the electromagnetic force experiment was taken on it. The electromagnetic field and electromagnetic force simulation analyses of experimental machine were taken, working out distribution data of electromagnetic force and magnetic induction intensity distribution curve, and the effects of permanent magnetic field on electromagnetic field and structure parameters on electromagnetic force. The simulation value is accord with experiment value, the research results provide a reference to electromagnetic force study on CRDM in CARR, and also provide a reference to design of the same type CRDM. (authors)

  19. Gauge unification of basic forces, particularly of gravitation with strong interactions

    International Nuclear Information System (INIS)

    Salam, A.

    1977-01-01

    An attempt is made to present a case for the use of both the Einstein--Weyl spin-two and the Yang--Mills spin-one gauge structures for describing strong interactions. By emphasizing both spin-one and -two aspects of this force, it is hoped that a unification of this force, on the one hand, with gravity theory and, on the other, with the electromagnetic and weak interactions can be achieved. A Puppi type of tetrahedral interralation of fundamental forces, with the strong force playing a pivotal role due to its mediation through both spin-one and -two quanta, is proposed. It is claimed that the gauge invariance of gravity theory permits the use of ambuguity-free nonpolynomial techniques and thereby the securing of relistic regularization in gravity-modified field theories with the Newtonian constant G/sub N/ providing a relistic cutoff. 37 references

  20. Big bang nucleosynthesis: The strong nuclear force meets the weak anthropic principle

    International Nuclear Information System (INIS)

    MacDonald, J.; Mullan, D. J.

    2009-01-01

    Contrary to a common argument that a small increase in the strength of the strong force would lead to destruction of all hydrogen in the big bang due to binding of the diproton and the dineutron with a catastrophic impact on life as we know it, we show that provided the increase in strong force coupling constant is less than about 50% substantial amounts of hydrogen remain. The reason is that an increase in strong force strength leads to tighter binding of the deuteron, permitting nucleosynthesis to occur earlier in the big bang at higher temperature than in the standard big bang. Photodestruction of the less tightly bound diproton and dineutron delays their production to after the bulk of nucleosynthesis is complete. The decay of the diproton can, however, lead to relatively large abundances of deuterium.

  1. Modified multiple time scale method for solving strongly nonlinear damped forced vibration systems

    Science.gov (United States)

    Razzak, M. A.; Alam, M. Z.; Sharif, M. N.

    2018-03-01

    In this paper, modified multiple time scale (MTS) method is employed to solve strongly nonlinear forced vibration systems. The first-order approximation is only considered in order to avoid complexicity. The formulations and the determination of the solution procedure are very easy and straightforward. The classical multiple time scale (MS) and multiple scales Lindstedt-Poincare method (MSLP) do not give desire result for the strongly damped forced vibration systems with strong damping effects. The main aim of this paper is to remove these limitations. Two examples are considered to illustrate the effectiveness and convenience of the present procedure. The approximate external frequencies and the corresponding approximate solutions are determined by the present method. The results give good coincidence with corresponding numerical solution (considered to be exact) and also provide better result than other existing results. For weak nonlinearities with weak damping effect, the absolute relative error measures (first-order approximate external frequency) in this paper is only 0.07% when amplitude A = 1.5 , while the relative error gives MSLP method is surprisingly 28.81%. Furthermore, for strong nonlinearities with strong damping effect, the absolute relative error found in this article is only 0.02%, whereas the relative error obtained by MSLP method is 24.18%. Therefore, the present method is not only valid for weakly nonlinear damped forced systems, but also gives better result for strongly nonlinear systems with both small and strong damping effect.

  2. Estimation of Muscle Force Based on Neural Drive in a Hemispheric Stroke Survivor.

    Science.gov (United States)

    Dai, Chenyun; Zheng, Yang; Hu, Xiaogang

    2018-01-01

    Robotic assistant-based therapy holds great promise to improve the functional recovery of stroke survivors. Numerous neural-machine interface techniques have been used to decode the intended movement to control robotic systems for rehabilitation therapies. In this case report, we tested the feasibility of estimating finger extensor muscle forces of a stroke survivor, based on the decoded descending neural drive through population motoneuron discharge timings. Motoneuron discharge events were obtained by decomposing high-density surface electromyogram (sEMG) signals of the finger extensor muscle. The neural drive was extracted from the normalized frequency of the composite discharge of the motoneuron pool. The neural-drive-based estimation was also compared with the classic myoelectric-based estimation. Our results showed that the neural-drive-based approach can better predict the force output, quantified by lower estimation errors and higher correlations with the muscle force, compared with the myoelectric-based estimation. Our findings suggest that the neural-drive-based approach can potentially be used as a more robust interface signal for robotic therapies during the stroke rehabilitation.

  3. The marriage between welfare services and tourism - A driving force for innovation?

    DEFF Research Database (Denmark)

    Hjalager, Anne Mette

    2006-01-01

    -based sectors are well connected with other sectors, including the voluntary sector. Both internal and external driving forces are continuously challenging the Danish welfare model. The pressures and the opportunities are transmitted to tourism, albeit not uniformly. There are good reasons for commercial...

  4. Transmission of government spending shocks in the Euro area: time variation and driving forces

    NARCIS (Netherlands)

    Kirchner, M.; Cimadomo, J.; Hauptmeier, S.

    This paper applies structural vector autoregressions with time-varying parameters in order to investigate changes in the effects of government spending shocks in the euro area, and the driving forces of those changes. Our contribution is two-fold. First, we present evidence that the short-run impact

  5. The driving force of the Na+/Ca2+-exchanger during metabolic inhibition

    NARCIS (Netherlands)

    Baartscheer, Antonius; Schumacher, Cees A.; Coronel, Ruben; Fiolet, Jan W. T.

    2011-01-01

    Objective: Metabolic inhibition causes a decline in mechanical performance and, if prolonged, myocardial contracture and cell death. The decline in mechanical performance is mainly due to altered intracellular calcium handling, which is under control of the Na+/Ca2+-exchanger (NCX) The driving force

  6. Emission of greenhouse gases 1990-2010. Trends and driving forces

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-03-01

    Emissions of greenhouse gases in Norway from 1990-2010 - trends and driving forces, a report that presents emission trends in Norway with the analysis of the main drivers and trends, and a review and analysis of the effectiveness of implemented measures.(Author)

  7. Current Reversal Due to Coupling Between Asymmetrical Driving Force and Ratchet Potential

    International Nuclear Information System (INIS)

    Ai Baoquan; Xie Huizhang; Liu Lianggang

    2006-01-01

    Transport of a Brownian particle moving in a periodic potential is investigated in the presence of an asymmetric unbiased external force. The asymmetry of the external force and the asymmetry of the potential are the two ways of inducing a net current. It is found that the competition of the spatial asymmetry of potential with the temporal asymmetry of the external force leads to the phenomena like current reversal. The competition between the two opposite driving factors is a necessary but not a sufficient condition for current reversals.

  8. Force analysis of the advanced neutron source control rod drive latch mechanism

    International Nuclear Information System (INIS)

    Damiano, B.

    1989-01-01

    The Advanced Neutron Source reactor (ANS), a proposed Department of Energy research reactor currently undergoing conceptual design at the Oak Ridge National Laboratory (ORNL), will generate a thermal neutron flux approximating 10 30 M -2 emdash S -1 . The compact core necessary to produce this flux provides little space for the shim safety control rods, which are located in the central annulus of the core. Without proper control rod drive design, the control rod drive magnets (which hold the control rod latch in a ready-to-scram position) may be unable to support the required load due to their restricted size. This paper describes the force analysis performed on the control rod latch mechanism to determine the fraction of control rod weight transferred to the drive magnet. This information will be useful during latch, control rod drive and magnet design. 5 refs., 12 figs

  9. Vehicle Dynamics Control of In-wheel Electric Motor Drive Vehicles Based on Averaging of Tire Force Usage

    Science.gov (United States)

    Masaki, Nobuo; Iwano, Haruo; Kamada, Takayoshi; Nagai, Masao

    For in-wheel electric motor drive vehicles, a new vehicle dynamics control which is based on the tire force usage rate is proposed. The new controller adopts non-linear optimal control could manage the interference between direct yaw-moment control and the tire force usage rate. The new control is considered total longitudinal and transverse tire force. Therefore the controller can prevent tire force saturation near tire force limit during cornering. Simulations and test runs by the custom made four wheel drive in-wheel motor electric vehicle show that higher driving stability performance compared to the performance of the same vehicle without control.

  10. Driving-forces model on individual behavior in scenarios considering moving threat agents

    Science.gov (United States)

    Li, Shuying; Zhuang, Jun; Shen, Shifei; Wang, Jia

    2017-09-01

    The individual behavior model is a contributory factor to improve the accuracy of agent-based simulation in different scenarios. However, few studies have considered moving threat agents, which often occur in terrorist attacks caused by attackers with close-range weapons (e.g., sword, stick). At the same time, many existing behavior models lack validation from cases or experiments. This paper builds a new individual behavior model based on seven behavioral hypotheses. The driving-forces model is an extension of the classical social force model considering scenarios including moving threat agents. An experiment was conducted to validate the key components of the model. Then the model is compared with an advanced Elliptical Specification II social force model, by calculating the fitting errors between the simulated and experimental trajectories, and being applied to simulate a specific circumstance. Our results show that the driving-forces model reduced the fitting error by an average of 33.9% and the standard deviation by an average of 44.5%, which indicates the accuracy and stability of the model in the studied situation. The new driving-forces model could be used to simulate individual behavior when analyzing the risk of specific scenarios using agent-based simulation methods, such as risk analysis of close-range terrorist attacks in public places.

  11. On the forces that drive and resist deformation of the south-central Mediterranean: a mechanical model study

    Science.gov (United States)

    Nijholt, Nicolai; Govers, Rob; Wortel, Rinus

    2018-04-01

    The geodynamics of the Mediterranean comprises a transitional setting in which slab rollback and plate convergence compete to shape the region. In the central Mediterranean, where the balance of driving and resisting forces changes continuously and rapidly since the Miocene, both kinematic and seismo-tectonic observations display a strong variation in deformation style and, therefore possibly, lithospheric forces. We aim to understand the current kinematics in southern Italy and Sicily in terms of lithospheric forces that cause them. The strong regional variation of geodetic velocities appears to prohibit such simple explanation. We use mechanical models to quantify the deformation resulting from large-scale Africa-Eurasia convergence, ESE retreat of the Calabrian subduction zone, pull by the Aegean slab, and regional variations in gravitational potential energy (topography). A key model element is the resistance to slip on major regional fault zones. We show that geodetic velocities, seismicity and sense of slip on regional faults can be understood to result from lithospheric forces. Our most important new finding is that regional variations in resistive tractions are required to fit the observations, with notably very low tractions on the Calabrian subduction contact, and a buildup towards a significant earthquake in the Calabrian fore-arc. We also find that the Calabrian net slab pull force is strongly reduced (compared to the value possible in view of the slab's dimensions) and that trench suction tractions are negligible. Such very small contributions to the present-day force balance in the south-central Mediterranean suggest that the Calabrian arc is now further transitioning towards a setting dominated by Africa-Eurasia plate convergence, whereas during the past 30 Myrs slab retreat continually was the dominant factor.

  12. Driving Forces of Plate Tectonics and Evolution of the Oceanic Lithosphere and Asthenosphere

    Science.gov (United States)

    Forsyth, D. W.

    2017-12-01

    As plate tectonics became established as an excellent kinematic description of the relative motions of different blocks of the Earth's lithosphere, many investigators also began exploring the forces involved in driving the plate motions. Because the plates move at nearly constant velocities over long periods of time and inertial terms are unimportant, driving forces must always be balanced by resisting forces in a way that regulates the velocities. Forsyth and Uyeda (1975) incorporated the balancing of torques on the individual plates to help constrain the relative importance of the driving and resisting forces, as parameterized in a way based on prior model investigations of individual parts of the convecting system. We found that the primary driving force was sinking of subducting lithosphere at trenches, balanced largely by viscous resisting forces in the sub-asthenospheric mantle; that viscous drag beneath the oceanic plates was negligible; and that mid-ocean ridges provided a relatively small push. One of the early questions was whether there was buoyant upwelling on a large scale beneath mid-ocean ridges as part of a whole mantle convection system with subduction of the plates representing the downwelling limb. If so, then it would be likely that the plates were just riding on top of large convection cells. Seismic tomography has demonstrated that, on average, there are no deep roots beneath mid-ocean ridges, so that active, buoyant upwelling from the deep mantle does not exist beneath spreading centers. However, more recent tomographic studies have found asymmetry of the shear velocity structure beneath ridges in some areas, pointing to a smaller scale of active convection in the shallow mantle perhaps induced by melt retention buoyancy or the local effects of ridge/hotspot interaction.

  13. A Study of the Effect of the Fringe Fields on the Electrostatic Force in Vertical Comb Drives

    Directory of Open Access Journals (Sweden)

    Else Gallagher

    2014-10-01

    Full Text Available The equation that describes the relationship between the applied voltage and the resulting electrostatic force within comb drives is often used to assist in choosing the dimensions for their design. This paper re-examines how some of these dimensions—particularly the cross-sectional dimensions of the comb teeth—affect this relationship in vertical comb drives. The electrostatic forces in several vertical comb drives fabricated for this study were measured and compared to predictions made with four different mathematical models in order to explore the amount of complexity required within a model to accurately predict the electrostatic forces in the comb drives.

  14. Agricultural land use change and associated driving forces over the past 180 years in two municipalities of the Brazilian Cerrado

    NARCIS (Netherlands)

    Arruda, de Murilo Rodrigues; Slingerland, Maja; Santos, José Zilton Lopes; Giller, Ken E.

    2018-01-01

    This paper aims to test the hypothesis that a single driving force from the local, national, or global level is capable of triggering land use changes, including large scale deforestation, within a historical context. To reach this goal we describe and explain the driving forces from the global to

  15. Position Control of Linear Synchronous Motor Drives with Exploitation of Forced Dynamics Control Principles

    Directory of Open Access Journals (Sweden)

    Jan Vittek

    2004-01-01

    Full Text Available Closed-loop position control of mechanisms directly driven by linear synchronous motors with permanent magnets is presented. The control strategy is based on forced dynamic control, which is a form of feedback linearisation, yielding a non-liner multivariable control law to obtain a prescribed linear speed dynamics together with the vector control condition of mutal orthogonality between the stator current and magnetic flux vectors (assuming perfect estimates of the plant parameters. Outer position control loop is closed via simple feedback with proportional gain. Simulations of the design control sysstem, including the drive with power electronic switching, predict the intended drive performance.

  16. Characteristics of strongly-forced turbulent jets and non-premixed jet flames

    Energy Technology Data Exchange (ETDEWEB)

    Lakshminarasimhan, K.; Ezekoye, O.A. [University of Texas at Austin, Department of Mechanical Engineering, Austin, TX (United States); Clemens, N.T. [University of Texas at Austin, Department of Aerospace Engineering and Engineering Mechanics, Austin, TX (United States)

    2006-10-15

    Previous researchers have demonstrated that strong pulsations of the fuel flow rate can significantly reduce the flame length and luminosity of laminar/transitional non-premixed jet flames. The physical mechanisms responsible for these changes are investigated experimentally in acoustically-forced jet flows where the peak velocity fluctuations are up to eight times the mean flow velocity. Both reacting and non-reacting flows were studied and Reynolds numbers, based on the mean flow properties, ranged from 800 to 10,000 (corresponding to peak Reynolds numbers of 1,450-23,000), and forcing frequencies ranged from 290 to 1,140 Hz. Both the first and second organ-pipe resonance modes of the fuel delivery tube were excited to obtain these frequencies. An analysis of the acoustic forcing characteristics within the resonance tube is provided in order to understand the source of the high amplitude forcing. Flow visualization of jets with first resonant forcing confirms the presence of large-scale coherent vortices and strong reverse flow near the exit of the fuel tube. With second-resonant forcing, however, vortices are not emitted from the tube as they are drawn back into the fuel tube before they can fully form. Increased fine-scale turbulence is associated with both resonant cases, but particularly at second resonance. The power spectra of the velocity fluctuations for a resonantly pulsed jet show the presence of an inertial subrange indicating that the flow becomes fully turbulent even for mean-Reynolds-number jets that are nominally laminar. It is shown that these pulsed jet flows exhibit strong similarities to synthetic jets and that the Strouhal number, based on the maximum velocity at the fuel tube exit, is the dominant parameter for scaling these flows. The Strouhal number determines the downstream location where the coherent vortices breakdown, and is found to provide better collapse of flame length data (both current and previous) than other parameters that have

  17. Analyzing the Long Term Cohesive Effect of Sector Specific Driving Forces.

    Directory of Open Access Journals (Sweden)

    Yonatan Berman

    Full Text Available Financial markets are partially composed of sectors dominated by external driving forces, such as commodity prices, infrastructure and other indices. We characterize the statistical properties of such sectors and present a novel model for the coupling of the stock prices and their dominating driving forces, inspired by mean reverting stochastic processes. Using the model we were able to explain the market sectors' long term behavior and estimate the coupling strength between stocks in financial markets and the sector specific driving forces. Notably, the analysis was successfully applied to the shipping market, in which the Baltic dry index (BDI, an assessment of the price of transporting the major raw materials by sea, influences the shipping financial market. We also present the analysis of other sectors-the gold mining market and the food production market, for which the model was also successfully applied. The model can serve as a general tool for characterizing the coupling between external forces and affected financial variables and therefore for estimating the risk in sectors and their vulnerability to external stress.

  18. Effects of strong bite force on the facial vertical dimension of pembarong performers

    Directory of Open Access Journals (Sweden)

    C. Christina

    2017-06-01

    Full Text Available Background: A pembarong performer is a reog dancer who bites on a piece of wood inserted into his/her mouth in order to support a 60 kg Barongan or Dadak Merak mask. The teeth supporting this large and heavy mask are directly affected, as the strong bite force exerted during a dance could affect their vertical and sagital facial dimensions. Purpose: This study aimed to examine the influence of the bite force of pembarong performers due to their vertical and sagital facial dimensions. Methods: The study reported here involved fifteen pembarong performers and thirteen individuals with normal occlusion (with specific criteria. The bite force of these subjects was measured with a dental prescale sensor during its centric occlusion. A cephalometric variation measurement was subsequently performed on all subjects with its effects on their vertical and sagital facial dimensions being measured. Results: The bite force value of the pembarong performers was 394.3816 ± 7.68787 Newtons, while the normal occlusion was 371.7784 ± 4.77791 Newtons. There was no correlation between the bite force and the facial sagital dimension of these subjects. However, a significant correlation did exist between bite force and lower facial height/total facial height (LFH/TFH ratio (p = 0.013. Conversely, no significant correlation between bite force and posterior facial height/total facial height (PFH/TFH ratio (p = 0.785 was detected. There was an inverse correlation between bite force and LFH/TFH ratio (r = -.464. Conclusion: Bite force is directly related to the decrease in LFH/TFH ratio. Occlusal pressure exerted by the posterior teeth on the alveolar bone may increase bone density at the endosteal surface of cortical bone.

  19. The effect of drive frequency and set point amplitude on tapping forces in atomic force microscopy: simulation and experiment

    International Nuclear Information System (INIS)

    Legleiter, Justin

    2009-01-01

    In tapping mode atomic force microscopy (AFM), a sharp probe tip attached to an oscillating cantilever is allowed to intermittently strike a surface. By raster scanning the probe while monitoring the oscillation amplitude of the cantilever via a feedback loop, topographical maps of surfaces with nanoscale resolution can be acquired. While numerous studies have employed numerical simulations to elucidate the time-resolved tapping force between the probe tip and surface, until recent technique developments, specific read-outs from such models could not be experimentally verified. In this study, we explore, via numerical simulation, the impact of imaging parameters, i.e. set point ratio and drive frequency as a function of resonance, on time-varying tip-sample force interactions, which are directly compared to reconstructed tapping forces from real AFM experiments. As the AFM model contains a feedback loop allowing for the simulation of the entire scanning process, we further explore the impact that various tip-sample force have on the entire imaging process.

  20. Optical switching based on the manipulation of microparticles in a colloidal liquid using strong scattering force

    International Nuclear Information System (INIS)

    Liu Jin; Liu Zheng-Qi; Feng Tian-Hua; Dai Qiao-Feng; Wu Li-Jun; Lan Sheng

    2010-01-01

    This paper demonstrates the realization of an optical switch by optically manipulating a large number of polystyrene spheres contained in a capillary. The strong scattering force exerted on polystyrene spheres with a large diameter of 4.3 μm is employed to realize the switching operation. A transparent window is opened for the signal light when the polystyrene spheres originally located at the beam centre are driven out of the beam region by the strong scattering force induced by the control light. The switching dynamics under different incident powers is investigated and compared with that observed in the optical switch based on the formation of optical matter. It is found that a large extinction ratio of ∼ 30 dB and fast switching-on and switching-off times can be achieved in this type of switch. (classical areas of phenomenology)

  1. Nanomagnets with high shape anisotropy and strong crystalline anisotropy: perspectives on magnetic force microscopy

    International Nuclear Information System (INIS)

    Campanella, H; Llobet, J; Esteve, J; Plaza, J A; Jaafar, M; Vázquez, M; Asenjo, A; Del Real, R P

    2011-01-01

    We report on a new approach for magnetic imaging, highly sensitive even in the presence of external, strong magnetic fields. Based on FIB-assisted fabricated high-aspect-ratio rare-earth nanomagnets, we produce groundbreaking magnetic force tips with hard magnetic character where we combine a high aspect ratio (shape anisotropy) together with strong crystalline anisotropy (rare-earth-based alloys). Rare-earth hard nanomagnets are then FIB-integrated to silicon microcantilevers as highly sharpened tips for high-field magnetic imaging applications. Force resolution and domain reversing and recovery capabilities are at least one order of magnitude better than for conventional magnetic tips. This work opens new, pioneering research fields on the surface magnetization process of nanostructures based either on relatively hard magnetic materials—used in magnetic storage media—or on materials like superparamagnetic particles, ferro/antiferromagnetic structures or paramagnetic materials.

  2. Large methane releases lead to strong aerosol forcing and reduced cloudiness

    DEFF Research Database (Denmark)

    Kurten, T.; Zhou, L.; Makkonen, R.

    2011-01-01

    forcing that is comparable in magnitude to the long-wave radiative forcing ("enhanced greenhouse effect") of the added methane. Together, the indirect CH4-O-3 and CH4-OHaerosol forcings could more than double the warming effect of large methane increases. Our findings may help explain the anomalously......The release of vast quantities of methane into the atmosphere as a result of clathrate destabilization is a potential mechanism for rapid amplification of global warming. Previous studies have calculated the enhanced warming based mainly on the radiative effect of the methane itself, with smaller...... contributions from the associated carbon dioxide or ozone increases. Here, we study the effect of strongly elevated methane (CH4) levels on oxidant and aerosol particle concentrations using a combination of chemistry-transport and general circulation models. A 10-fold increase in methane concentrations...

  3. Scalable fabrication of strongly textured organic semiconductor micropatterns by capillary force lithography.

    Science.gov (United States)

    Jo, Pil Sung; Vailionis, Arturas; Park, Young Min; Salleo, Alberto

    2012-06-26

    Strongly textured organic semiconductor micropatterns made of the small molecule dioctylbenzothienobenzothiophene (C(8)-BTBT) are fabricated by using a method based on capillary force lithography (CFL). This technique provides the C(8)-BTBT solution with nucleation sites for directional growth, and can be used as a scalable way to produce high quality crystalline arrays in desired regions of a substrate for OFET applications. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Instanton and tensor-force effects in the strong decays of mesons

    International Nuclear Information System (INIS)

    Bonnaz, R.; Silvestre-Brac, B.

    2001-01-01

    The strong decays of mesons are studied in the framework of the 3 P 0 model with a momentum-dependent vertex. The mesons wave functions are obtained from quark-antiquark potentials including a finite quark size, instanton effects, spin-orbit and tensor-force effects. Several prescriptions for treating the decays into three mesons are proposed and analyzed. Comparison to experimental data is presented in detail. (author)

  5. Oxidized cholesterol as the driving force behind the development of Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    Paola eGamba

    2015-06-01

    Full Text Available Alzheimer’s disease (AD, the most common neurodegenerative disorder associated with dementia, is typified by the pathological accumulation of amyloid β peptides and neurofibrillary tangles within the brain. Considerable evidence indicates that many events contribute to AD progression, including oxidative stress, inflammation, and altered cholesterol metabolism.The brain’s high lipid content makes it particularly vulnerable to oxidative species, with the consequent enhancement of lipid peroxidation and cholesterol oxidation, and the subsequent formation of end products, mainly 4-hydroxynonenal and oxysterols, respectively from the two processes. The chronic inflammatory events observed in the AD brain include activation of microglia and astrocytes, together with enhancement of inflammatory molecule and free radical release. Along with glial cells, neurons themselves have been found to contribute to neuroinflammation in the AD brain, by serving as sources of inflammatory mediators. Oxidative stress is intimately associated with neuroinflammation, and a vicious circle has been found to connect oxidative stress and inflammation in AD. Alongside oxidative stress and inflammation, altered cholesterol metabolism and hypercholesterolemia also significantly contribute to neuronal damage and to progression of AD. Increasing evidence is now consolidating the hypothesis that oxidized cholesterol is the driving force behind the development of AD, and that oxysterols are the link connecting the disease to altered cholesterol metabolism in the brain and hypercholesterolemia; this is because of the ability of oxysterols, unlike cholesterol, to cross the blood brain barrier. The key role of oxysterols in AD pathogenesis has been strongly supported by research pointing to their involvement in modulating neuroinflammation, Aβ accumulation, and cell death.This review highlights the key role played by cholesterol and oxysterols in the brain in AD pathogenesis.

  6. Jeans instability in collisional strongly coupled dusty plasma with radiative condensation and polarization force

    International Nuclear Information System (INIS)

    Prajapati, R. P.; Bhakta, S.; Chhajlani, R. K.

    2016-01-01

    The influence of dust-neutral collisions, polarization force, and electron radiative condensation is analysed on the Jeans (gravitational) instability of partially ionized strongly coupled dusty plasma (SCDP) using linear perturbation (normal mode) analysis. The Boltzmann distributed ions, dynamics of inertialess electrons, charged dust and neutral particles are considered. Using the plane wave solutions, a general dispersion relation is derived which is modified due to the presence of dust-neutral collisions, strong coupling effect, polarization force, electron radiative condensation, and Jeans dust/neutral frequencies. In the long wavelength perturbations, the Jeans instability criterion depends upon strong coupling effect, polarization interaction parameter, and thermal loss, but it is independent of dust-neutral collision frequency. The stability of the considered configuration is analysed using the Routh–Hurwitz criterion. The growth rates of Jeans instability are illustrated, and stabilizing influence of viscoelasticity and dust-neutral collision frequency while destabilizing effect of electron radiative condensation, polarization force, and Jeans dust-neutral frequency ratio is observed. This work is applied to understand the gravitational collapse of SCDP with dust-neutral collisions.

  7. Electronic structure and driving forces in {beta}-cyclodextrin: Diclofenac inclusion complexes

    Energy Technology Data Exchange (ETDEWEB)

    Bogdan, Diana [National Institute for Research and Development of Isotopic and Molecular Technologies, Donath street 71-103, 400293 Cluj-Napoca (Romania); Morari, C. [National Institute for Research and Development of Isotopic and Molecular Technologies, Donath street 71-103, 400293 Cluj-Napoca (Romania)]. E-mail: cristim@s3.itim-cj.ro

    2007-07-02

    We investigate the geometry and electronic structure for complexes of {beta}-cyclodextrin with diclofenac using DFT calculations. The effect of solvent is explicitly taken into account. This investigation allows us to draw meaningful conclusions upon the stability of the complex and the nature of the driving forces leading to the complexation process. In particular we emphasize the role of the water, by pointing out the changes in the solvent's electronic structure for different docking geometries.

  8. Electronic structure and driving forces in β-cyclodextrin: Diclofenac inclusion complexes

    International Nuclear Information System (INIS)

    Bogdan, Diana; Morari, C.

    2007-01-01

    We investigate the geometry and electronic structure for complexes of β-cyclodextrin with diclofenac using DFT calculations. The effect of solvent is explicitly taken into account. This investigation allows us to draw meaningful conclusions upon the stability of the complex and the nature of the driving forces leading to the complexation process. In particular we emphasize the role of the water, by pointing out the changes in the solvent's electronic structure for different docking geometries

  9. The world food situation: New driving forces and required actions [In Chinese

    OpenAIRE

    von Braun, Joachim

    2008-01-01

    "The world food situation is currently being rapidly redefined by new driving forces. Income growth, climate change, high energy prices, globalization, and urbanization are transforming food consumption, production, and markets. The influence of the private sector in the world food system, especially the leverage of food retailers, is also rapidly increasing. Changes in food availability, rising commodity prices, and new producer–consumer linkages have crucial implications for the livelihoods...

  10. Spatiotemporal Variation of Driving Forces for Settlement Expansion in Different Types of Counties

    Directory of Open Access Journals (Sweden)

    Guanglong Dong

    2015-12-01

    Full Text Available Understanding the process of settlement expansion and the spatiotemporal variation of driving forces is the foundation of rational and specific planning for sustainable development. However, little attention has been paid to the spatiotemporal differences of driving forces among different counties, especially when they are representatives of different development types. This study used Guanyun, Kunshan and Changshu as case studies, and binary logistic regression was employed. The results showed that the expansion rates of Kunshan and Changshu were 5.55 and 3.93 times higher than that of Guanyun. The combinations and relative importance of drivers varied with counties and periods. The change in the number of driving forces can be divided into three stages: increasing stage, decreasing stage, and stable stage. In the relatively developed counties, Kunshan and Changshu, the importance of population is decreased, while it remain an important factor in the less developed county, Guanyun. In addition, the effect of GDP stays the same in Kunshan while it becomes the most important factor in Changshu. The distance to the main road and the distance to town are increasingly important in Kunshan and Guanyun, and distance to town has been the only common factor in the last period, indicating the discrepancy is increased. The relative importance of distance to a lake in Kunshan and Changshu increased, reflecting the role of increasing tourism in accelerating settlement expansion.

  11. Magnetostatic torsional actuator with embedded nickel structures for the improvement of driving force and wobble motion

    International Nuclear Information System (INIS)

    Tang, Tsung-Lin; Fang, Weileun

    2011-01-01

    This study demonstrates the magnetostatic torsional actuator consisting in a Si–Ni compound frame to significantly improve the driving force. The present design has three merits: (1) it employs a Si mold to simultaneously electroplate/pattern thick Ni, and the Ni and Si structures respectively provide magnetostatic force and superior mechanical properties, (2) the embedded Ni structures not only increase the ferromagnetic material volume but also enhance magnetization strength to enlarge magnetostatic torque, (3) the Si–Ni compound structure, which is nearly symmetric about the torsional axis in the out-of-plane direction, can decrease the moment of inertia and also reduce the wobble motion. In applications, one-axis torsional actuator is implemented and characterized. The experiments show that the Si–Ni compound scanner has an optical scan angle θ optical = 90° with the input power 81 mW. The input power is decreased as compared with the existing scanner. Moreover, the out-of-plane wobble motion is only 44 nm at θ optical = 15°. Compared with the existing designs consisted of asymmetric structures in the out-of-plane direction, such as electroplated film and silicon rib, about the torsional axis, the equivalent eccentric force is reduced nearly two-fold. In short, the proposed design not only increases the driving force but also decreases the wobble motion

  12. Dissipative two-level system under strong ac driving: A combination of Floquet and Van Vleck perturbation theory

    International Nuclear Information System (INIS)

    Hausinger, Johannes; Grifoni, Milena

    2010-01-01

    We study the dissipative dynamics of a two-level system (TLS) exposed to strong ac driving. By combining Floquet theory with Van Vleck perturbation theory in the TLS tunneling matrix element, we diagonalize the time-dependent Hamiltonian and provide corrections to the renormalized Rabi frequency of the TLS, which are valid for both a biased and unbiased TLS and go beyond the known high-frequency and rotating-wave results. In order to mimic environmental influences on the TLS, we couple the system weakly to a thermal bath and solve analytically the corresponding Floquet-Bloch-Redfield master equation. We give a closed expression for the relaxation and dephasing rates of the TLS and discuss their behavior under variation of the driving amplitude. Further, we examine the robustness of coherent destruction of tunneling (CDT) and driving-induced tunneling oscillations (DITO). We show that also for a moderate driving frequency an almost complete suppression of tunneling can be achieved for short times and demonstrate the sensitiveness of DITO to a change of the external parameters.

  13. Mechanisms driving variability in the ocean forcing of Pine Island Glacier.

    Science.gov (United States)

    Webber, Benjamin G M; Heywood, Karen J; Stevens, David P; Dutrieux, Pierre; Abrahamsen, E Povl; Jenkins, Adrian; Jacobs, Stanley S; Ha, Ho Kyung; Lee, Sang Hoon; Kim, Tae Wan

    2017-02-17

    Pine Island Glacier (PIG) terminates in a rapidly melting ice shelf, and ocean circulation and temperature are implicated in the retreat and growing contribution to sea level rise of PIG and nearby glaciers. However, the variability of the ocean forcing of PIG has been poorly constrained due to a lack of multi-year observations. Here we show, using a unique record close to the Pine Island Ice Shelf (PIIS), that there is considerable oceanic variability at seasonal and interannual timescales, including a pronounced cold period from October 2011 to May 2013. This variability can be largely explained by two processes: cumulative ocean surface heat fluxes and sea ice formation close to PIIS; and interannual reversals in ocean currents and associated heat transport within Pine Island Bay, driven by a combination of local and remote forcing. Local atmospheric forcing therefore plays an important role in driving oceanic variability close to PIIS.

  14. Physical driving force of actomyosin motility based on the hydration effect.

    Science.gov (United States)

    Suzuki, Makoto; Mogami, George; Ohsugi, Hideyuki; Watanabe, Takahiro; Matubayasi, Nobuyuki

    2017-12-01

    We propose a driving force hypothesis based on previous thermodynamics, kinetics and structural data as well as additional experiments and calculations presented here on water-related phenomena in the actomyosin systems. Although Szent-Györgyi pointed out the importance of water in muscle contraction in 1951, few studies have focused on the water science of muscle because of the difficulty of analyzing hydration properties of the muscle proteins, actin, and myosin. The thermodynamics and energetics of muscle contraction are linked to the water-mediated regulation of protein-ligand and protein-protein interactions along with structural changes in protein molecules. In this study, we assume the following two points: (1) the periodic electric field distribution along an actin filament (F-actin) is unidirectionally modified upon binding of myosin subfragment 1 (M or myosin S1) with ADP and inorganic phosphate Pi (M.ADP.Pi complex) and (2) the solvation free energy of myosin S1 depends on the external electric field strength and the solvation free energy of myosin S1 in close proximity to F-actin can become the potential force to drive myosin S1 along F-actin. The first assumption is supported by integration of experimental reports. The second assumption is supported by model calculations utilizing molecular dynamics (MD) simulation to determine solvation free energies of a small organic molecule and two small proteins. MD simulations utilize the energy representation method (ER) and the roughly proportional relationship between the solvation free energy and the solvent-accessible surface area (SASA) of the protein. The estimated driving force acting on myosin S1 is as high as several piconewtons (pN), which is consistent with the experimentally observed force. © 2017 Wiley Periodicals, Inc.

  15. ASEAN-5 Passenger Car Industry Outlook: The Driving Forces, Opportunities and Challenges

    OpenAIRE

    Quek, Wu Kheng

    2010-01-01

    Global automotive industry is growing at an unprecedented speed in the past decade, primarily due to the strong and fastest growing demand from the Asian emerging economies. ASEAN-5 is an economic block with huge potential. It is an attractive alternative destination for business compare with other emerging economies. Total population is 420 million people and combined economic size of $1,355 billion in this region. ASEAN-5 countries are one of the major driving markets contributed to the rap...

  16. Drag force in strongly coupled, anisotropic plasma at finite chemical potential

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, Somdeb; Haque, Najmul [Theory Division, Saha Institute of Nuclear Physics,1/AF Bidhannagar, Kolkata-700 064 (India)

    2014-12-30

    We employ methods of gauge/string duality to analyze the drag force on a heavy quark moving through a strongly coupled, anisotropic N=4,SU(N) super Yang-Mills plasma in the presence of a finite U(1) chemical potential. We present numerical results valid for any value of the anisotropy parameter and the U(1) charge density and arbitrary direction of the quark velocity with respect to the direction of anisotropy. In the small anisotropy limit we are also able to furnish analytical results.

  17. Hartree-Fock calculations for strongly deformed and highly excited nuclei using the Skyrme force

    International Nuclear Information System (INIS)

    Zint, P.G.

    1975-01-01

    It has been shown that in CHF-calculations the Skyrme-force is usefull to describe strongly deformed nuclei with even proton and neutron number till separation. Thereby the eigenfunctions of the two-centre Hamiltonian form an adequate basis. With this procedure, we obtain the correct deformation of the 32 S-system. Induding the spurious energy of relative motion between the 16 O-fragments, the energy curve is a good approximation for the real potential, extracted form scattering experiments. (orig./WL) [de

  18. ANALYTICAL SYNTHESIS OF FORCED PULSE ELECTRONIC DRIVE CONTROL OF A TRACKING SYSTEM

    Directory of Open Access Journals (Sweden)

    A. S. Abufanas

    2017-01-01

    Full Text Available The problem of analytical synthesis of a control signal by a linear dynamical system is considered. As an optimization criterion, it is proposed to consider the transition time of the system from the initial state to a given final state. This type of control is called forced, providing the maximum system speed. The principle of solving this problem is considered on the basis of application of uncertain Lagrange multipliers and the Pontryagin maximum principle. Expressions are obtained for the matrix of transitions of the system and the control signal in a vector form.As an example, the electric drive described by the widespread second-order mathematical model is considered to evaluate the efficiency of the proposed method. Qualitative illustrations of the operability of the proposed approach, obtained by modeling in the Mathcad environment, and quantitative characteristics of the change in the input and output signals of the hypothetical control system are presented. It is shown that the use of forced control does not lead to the output of variables characterizing the state of the system, beyond the limits of admissible values.The use of forced control makes it possible to synthesize the control law in the form of a sequence of rectangular pulses of constant amplitude determined by the power source, variable duty cycle and polarity. This approach can be used for the control of DC-type DC motors used in various tracking systems used on unmanned aerial vehicles. Key words: forced control, target function, electric drive, pulse train. The use of forced control makes it possible to synthesize the control law in the form of a sequence of rectangular pulses of constant amplitude determined by the power source, variable duty cycle and polarity. This approach can be used for the control of DC-type DC motors used in various tracking systems used on unmanned aerial vehicles.

  19. Finite Element Analysis of the Vertical Levitation Force in an Electrostatic MEMS Comb Drive Actuator

    International Nuclear Information System (INIS)

    Wooldridge, J; Blackburn, J; Muniz-Piniella, A; Stewart, M; Shean, T A V; Weaver, P M; Cain, M G

    2013-01-01

    A vertical levitation electrostatic comb drive actuator was manufactured for the purpose of measuring piezoelectric coefficients in small-scale materials and devices. Previous modelling work on comb drive levitation has focussed on control of the levitation in standard poly-silicon devices in order to minimize effects on lateral modes of operation required for the accelerometer and gyroscope applications. The actuator developed in this study was manufactured using a 20 μm electroplated Ni process with a 25 μm trench created beneath the released structure through chemical wet etching. A finite element analysis using ZINC was used to model electrostatic potential around a cross section of one static and one movable electrode, from which the net levitation force per unit electrode was calculated. The model was first verified using the electrode geometry from previously studied systems, and then used to study the variation of force as a function of decreasing substrate-electrode distance. With the top electrode surfaces collinear the calculated force density is 0.00651 ε 0 V 2 M μm −1 , equivalent to a total force for the device of 36.4 μN at an applied voltage of V M =100 V, just 16% larger than the observed value. The measured increase in force with distance was smaller than predicted with the FEA, due to the geometry of the device in which the electrodes at the anchored ends of the supporting spring structure displace by a smaller amount than those at the centre

  20. Trends and driving forces of ecological training and education in the context of ecological education environment of the technical university

    OpenAIRE

    Danilenkova V. A.

    2017-01-01

    common patterns of ecological training and education in the technical university are analyzed in this article, their descriptions are defined. Driving forces of ecological training and education in the context of ecological education environment are discovered and proved. According to conducted research the author makes a proposition to point out at ecological risks as driving forces, searching for which improves the efficiency and effectiveness of ecological education environment. The resear...

  1. Escape rate for nonequilibrium processes dominated by strong non-detailed balance force

    Science.gov (United States)

    Tang, Ying; Xu, Song; Ao, Ping

    2018-02-01

    Quantifying the escape rate from a meta-stable state is essential to understand a wide range of dynamical processes. Kramers' classical rate formula is the product of an exponential function of the potential barrier height and a pre-factor related to the friction coefficient. Although many applications of the rate formula focused on the exponential term, the prefactor can have a significant effect on the escape rate in certain parameter regions, such as the overdamped limit and the underdamped limit. There have been continuous interests to understand the effect of non-detailed balance on the escape rate; however, how the prefactor behaves under strong non-detailed balance force remains elusive. In this work, we find that the escape rate formula has a vanishing prefactor with decreasing friction strength under the strong non-detailed balance limit. We both obtain analytical solutions in specific examples and provide a derivation for more general cases. We further verify the result by simulations and propose a testable experimental system of a charged Brownian particle in electromagnetic field. Our study demonstrates that a special care is required to estimate the effect of prefactor on the escape rate when non-detailed balance force dominates.

  2. Measurements of Properties of the Strong and Electroweak forces with the ATLAS detector at the LHC

    CERN Document Server

    Gregersen, Kristian; The ATLAS collaboration

    2015-01-01

    The Standard Model of particle physics is built around the idea of local gauge symmetries, leading to the existence of vector bosons, mediators of the strong and electroweak forces. The production of single and multiple electroweak vector bosons in p-p collisions in LHC Run-1 has been extensively studied by the ATLAS Collaboration. The production of charged and neutral weak gauge bosons via the Drell Yan process, is sensitive to high-order effects in the strong force, the proton structure and electroweak corrections. Cross section measurements of a W or Z boson in association with up to seven jets are reported. Interference effects between the exchange of photons and Z bosons can be used for the measurements of Standard Model parameters with high precision, such as the weak mixing angle from the forward-backward asymmetry. The Standard Model makes detailed predictions on the production of multiple W, Z and isolated photons, which are fixed by the gauge symmetry. Measurements involving two or three bosons in t...

  3. Measurements of Properties of the Strong and Electroweak forces with the ATLAS detector at the LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00236292; The ATLAS collaboration

    2016-01-01

    The Standard Model of particle physics is built around the idea of local gauge symmetries, leading to the existence of vector bosons, mediators of the strong and electroweak forces. The production of single and multiple electroweak vector bosons in p-p collisions in LHC Run-1 has been extensively studied by the ATLAS Collaboration. The production of charged and neutral weak gauge bosons via the Drell Yan process, is sensitive to high-order effects in the strong force, the proton structure and electroweak corrections. Cross section measurements of a W or Z boson in association with up to seven jets are reported. Interference effects between the exchange of photons and Z bosons can be used for the measurements of Standard Model parameters with high precision, such as the weak mixing angle from the forward-backward asymmetry. The Standard Model makes detailed predictions on the production of multiple W, Z and isolated photons, which are fixed by the gauge symmetry. Measurements involving two or three bosons in t...

  4. Large methane releases lead to strong aerosol forcing and reduced cloudiness

    Directory of Open Access Journals (Sweden)

    T. Kurtén

    2011-07-01

    Full Text Available The release of vast quantities of methane into the atmosphere as a result of clathrate destabilization is a potential mechanism for rapid amplification of global warming. Previous studies have calculated the enhanced warming based mainly on the radiative effect of the methane itself, with smaller contributions from the associated carbon dioxide or ozone increases. Here, we study the effect of strongly elevated methane (CH4 levels on oxidant and aerosol particle concentrations using a combination of chemistry-transport and general circulation models. A 10-fold increase in methane concentrations is predicted to significantly decrease hydroxyl radical (OH concentrations, while moderately increasing ozone (O3. These changes lead to a 70 % increase in the atmospheric lifetime of methane, and an 18 % decrease in global mean cloud droplet number concentrations (CDNC. The CDNC change causes a radiative forcing that is comparable in magnitude to the longwave radiative forcing ("enhanced greenhouse effect" of the added methane. Together, the indirect CH4-O3 and CH4-OH-aerosol forcings could more than double the warming effect of large methane increases. Our findings may help explain the anomalously large temperature changes associated with historic methane releases.

  5. Force Sensitive Handles and Capacitive Touch Sensor for Driving a Flexible Haptic-Based Immersive System

    OpenAIRE

    Covarrubias, Mario; Bordegoni, Monica; Cugini, Umberto

    2013-01-01

    In this article, we present an approach that uses both two force sensitive handles (FSH) and a flexible capacitive touch sensor (FCTS) to drive a haptic-based immersive system. The immersive system has been developed as part of a multimodal interface for product design. The haptic interface consists of a strip that can be used by product designers to evaluate the quality of a 3D virtual shape by using touch, vision and hearing and, also, to interactively change the shape of the virtual object...

  6. Remote sensing monitoring and driving force analysis to forest and greenbelt in Zhuhai

    Science.gov (United States)

    Yuliang Qiao, Pro.

    As an important city in the southern part of Chu Chiang Delta, Zhuhai is one of the four special economic zones which are opening up to the outside at the earliest in China. With pure and fresh air and trees shading the street, Zhuhai is a famous beach port city which is near the mountain and by the sea. On the basis of Garden City, the government of Zhuhai decides to build National Forest City in 2011, which firstly should understand the situation of greenbelt in Zhuhai in short term. Traditional methods of greenbelt investigation adopt the combination of field surveying and statistics, whose efficiency is low and results are not much objective because of artificial influence. With the adventure of the information technology such as remote sensing to earth observation, especially the launch of many remote sensing satellites with high resolution for the past few years, kinds of urban greenbelt information extraction can be carried out by using remote sensing technology; and dynamic monitoring to spatial pattern evolvement of forest and greenbelt in Zhuhai can be achieved by the combination of remote sensing and GIS technology. Taking Landsat5 TM data in 1995, Landsat7 ETM+ data in 2002, CCD and HR data of CBERS-02B in 2009 as main information source, this research firstly makes remote sensing monitoring to dynamic change of forest and greenbelt in Zhuhai by using the combination of vegetation coverage index and three different information extraction methods, then does a driving force analysis to the dynamic change results in 3 months. The results show: the forest area in Zhuhai shows decreasing tendency from 1995 to 2002, increasing tendency from 2002 to 2009; overall, the forest area show a small diminution tendency from 1995 to 2009. Through the comparison to natural and artificial driving force, the artificial driving force is the leading factor to the change of forest and greenbelt in Zhuhai. The research results provide a timely and reliable scientific basis

  7. Temperature and rainfall strongly drive temporal growth variation in Asian tropical forest trees.

    Science.gov (United States)

    Vlam, Mart; Baker, Patrick J; Bunyavejchewin, Sarayudh; Zuidema, Pieter A

    2014-04-01

    Climate change effects on growth rates of tropical trees may lead to alterations in carbon cycling of carbon-rich tropical forests. However, climate sensitivity of broad-leaved lowland tropical trees is poorly understood. Dendrochronology (tree-ring analysis) provides a powerful tool to study the relationship between tropical tree growth and annual climate variability. We aimed to establish climate-growth relationships for five annual-ring forming tree species, using ring-width data from 459 canopy and understory trees from a seasonal tropical forest in western Thailand. Based on 183/459 trees, chronologies with total lengths between 29 and 62 years were produced for four out of five species. Bootstrapped correlation analysis revealed that climate-growth responses were similar among these four species. Growth was significantly negatively correlated with current-year maximum and minimum temperatures, and positively correlated with dry-season precipitation levels. Negative correlations between growth and temperature may be attributed to a positive relationship between temperature and autotrophic respiration rates. The positive relationship between growth and dry-season precipitation levels likely reflects the strong water demand during leaf flush. Mixed-effect models yielded results that were consistent across species: a negative effect of current wet-season maximum temperatures on growth, but also additive positive effects of, for example, prior dry-season maximum temperatures. Our analyses showed that annual growth variability in tropical trees is determined by a combination of both temperature and precipitation variability. With rising temperature, the predominantly negative relationship between temperature and growth may imply decreasing growth rates of tropical trees as a result of global warming.

  8. Driving forces behind the Chinese public's demand for improved environmental safety.

    Science.gov (United States)

    Wen, Ting; Wang, Jigan; Ma, Zongwei; Bi, Jun

    2017-12-15

    Over the past decades, the public demand for improved environmental safety keeps increasing in China. This study aims to assess the driving forces behind the increasing public demand for improved environmental safety using a provincial and multi-year (1995, 2000, 2005, 2010, and 2014) panel data and the Stochastic Impacts by Regression on Population, Affluence, and Technology (STIRPAT) model. The potential driving forces investigated included population size, income levels, degrees of urbanization, and educational levels. Results show that population size and educational level are positively (Pdemand for improved environmental safety. No significant impact on demand was found due to the degree of urbanization. For the impact due to income level, an inverted U-shaped curve effect with the turning point of ~140,000 CNY GDP per capita is indicated. Since per capita GDP of 2015 in China was approximately 50,000 CNY and far from the turning point, the public demand for improved environmental safety will continue rising in the near future. To meet the increasing public demand for improved environmental safety, proactive and risk prevention based environmental management systems coupled with effective environmental risk communication should be established. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Negotiating EU CO2/energy taxation. Political economic driving forces and barriers

    International Nuclear Information System (INIS)

    Klok, Jacob

    2001-11-01

    The primary objective of this project is to identify the main political economic driving forces behind and barriers against the creation of an EU agreement on CO 2 /energy taxation. The analysis is based on a theoretical framework for understanding European integration and on detailed historical investigations into a process of EU negotiations concerning CO 2 /energy taxation that took place from the 1980s to 1994. Following the historical analysis of political economic driving forces and barriers, some overall perspectives on possible future developments within the field of EU CO 2 /energy taxation are finally advanced. The secondary objective of the project is to consider the possible effects on the EU negotiation process of Danish efforts to push the CO 2 /energy tax proposal from the late 1980s to 994. This analysis is based on the preceding historical analysis of the EU negotiation process, as well as further investigations into the national Danish development within the field of CO 2 /energy taxation, including accounts of Denmark's particular relations with the EU during the period in question. Finally, based on the likely future developments in the field EU CO 2 /energy taxation. Denmark's strategic opportunities are outlined. (BA)

  10. Driving forces behind the construction of an eco-compensation mechanism for wetlands in China

    Science.gov (United States)

    Wang, Changhai

    2016-09-01

    This research revealed important driving forces behind the construction of an eco-compensation mechanism for wetlands (DFEMW) in China. Using China's provincial panel data from 1978 to 2008, a fixed-effects model was used to analyze the impacts of agricultural production systems on wetlands. We identified three DFEMW as follows: the change of wetland resources and protection measures in China; declaration and implementation of the provincial Wetland Protection Ordinance; and wetland degradation by agricultural production systems, which necessitated the establishment of a wetland eco-compensation mechanism. In addition to the DFEMW, a significant positive correlation between wetland area and both rural population and gross agricultural production was identified, in addition to a negative correlation with chemical fertilizer usage, reservoir storage capacity, and irrigation area. The underlying reasons for the serious degradation and inadequate protection of wetlands were market failure and government failure; these were the driving forces behind the need to establish a wetland eco-compensation mechanism. From a governmental perspective, it has been difficult to rectify market failures in resource distribution and thus to prevent wetland degradation. Factors include conflicts of interest, lack of investment, effective special laws, a simple means to protect wetlands, and a multidisciplinary management system. Therefore, the key factor is the coordination of interest relationships between those who utilize wetlands and those who seek to minimize wetland degradation and effectively protect wetlands.

  11. Driving forces and barriers for environmental technology development; Drivkrefter og barrierer for utvikling av miljoeteknologi

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    Driving forces and barriers behind development and usage of environmental technology is discussed, and also whether there are certain characteristics related to environmental innovations compared to other innovations in general. The development of environmental technology is in principle dominated by the same drivers and barriers as any other technology, but the order and strength of the various factors may be different. This examination as well as other empirical studies shows that regulations play a greater part for environmental technology than 'pure market forces'. To many participants it is important to be one step ahead of the regulations, i.e. the expected regulations are equally important as the factual ones in driving the technology development. Players in the business community express that it is important that the authorities cooperate with them when introducing new regulations. This will increase acceptance for the regulations and facilitate the necessary adjustments. The most important barrier in the development and use of the technologies studied is probably the lack of demand.

  12. Salticid predation as one potential driving force of ant mimicry in jumping spiders

    Science.gov (United States)

    Huang, Jin-Nan; Cheng, Ren-Chung; Li, Daiqin; Tso, I-Min

    2011-01-01

    Many spiders possess myrmecomorphy, and species of the jumping spider genus Myrmarachne exhibit nearly perfect ant mimicry. Most salticids are diurnal predators with unusually high visual acuity that prey on various arthropods, including conspecifics. In this study, we tested whether predation pressure from large jumping spiders is one possible driving force of perfect ant mimicry in jumping spiders. The results showed that small non-ant-mimicking jumping spiders were readily treated as prey by large ones (no matter whether heterospecific or conspecific) and suffered high attack and mortality rates. The size difference between small and large jumping spiders significantly affected the outcomes of predatory interactions between them: the smaller the juvenile jumping spiders, the higher the predation risk from large ones. The attack and mortality rates of ant-mimicking jumping spiders were significantly lower than those of non-ant-mimicking jumping spiders, indicating that a resemblance to ants could provide protection against salticid predation. However, results of multivariate behavioural analyses showed that the responses of large jumping spiders to ants and ant-mimicking salticids differed significantly. Results of this study indicate that predation pressure from large jumping spiders might be one selection force driving the evolution of nearly perfect myrmecomorphy in spiders and other arthropods. PMID:20961898

  13. Selective forces and mutational biases drive stop codon usage in the human genome: a comparison with sense codon usage.

    Science.gov (United States)

    Trotta, Edoardo

    2016-05-17

    The three stop codons UAA, UAG, and UGA signal the termination of mRNA translation. As a result of a mechanism that is not adequately understood, they are normally used with unequal frequencies. In this work, we showed that selective forces and mutational biases drive stop codon usage in the human genome. We found that, in respect to sense codons, stop codon usage was affected by stronger selective forces but was less influenced by neutral mutational biases. UGA is the most frequent termination codon in human genome. However, UAA was the preferred stop codon in genes with high breadth of expression, high level of expression, AT-rich coding sequences, housekeeping functions, and in gene ontology categories with the largest deviation from expected stop codon usage. Selective forces associated with the breadth and the level of expression favoured AT-rich sequences in the mRNA region including the stop site and its proximal 3'-UTR, but acted with scarce effects on sense codons, generating two regions, upstream and downstream of the stop codon, with strongly different base composition. By favouring low levels of GC-content, selection promoted labile local secondary structures at the stop site and its proximal 3'-UTR. The compositional and structural context favoured by selection was surprisingly emphasized in the class of ribosomal proteins and was consistent with sequence elements that increase the efficiency of translational termination. Stop codons were also heterogeneously distributed among chromosomes by a mechanism that was strongly correlated with the GC-content of coding sequences. In human genome, the nucleotide composition and the thermodynamic stability of stop codon site and its proximal 3'-UTR are correlated with the GC-content of coding sequences and with the breadth and the level of gene expression. In highly expressed genes stop codon usage is compositionally and structurally consistent with highly efficient translation termination signals.

  14. Periodic Forcing of a 555-IC Based Electronic Oscillator in the Strong Coupling Limit

    Science.gov (United States)

    Santillán, Moisés

    We designed and developed a master-slave electronic oscillatory system (based on the 555-timer IC working in the astable mode), and investigated its dynamic behavior regarding synchronization. For that purpose, we measured the rotation numbers corresponding to the phase-locking rhythms achieved in a large set of values of the normalized forcing frequency (NFF) and of the coupling strength between the master and the slave oscillators. In particular, we were interested in the system behavior in the strong-coupling limit, because such problem has not been extensively studied from an experimental perspective. Our results indicate that, in such a limit, a degenerate codimension-2 bifurcation point at NFF = 2 exists, in which all the phase-locking regions converge. These findings were corroborated by means of a mathematical model developed to that end, as well as by ad hoc further experiments.

  15. Strong modification of stratospheric ozone forcing by cloud and sea-ice adjustments

    Directory of Open Access Journals (Sweden)

    Y. Xia

    2016-06-01

    Full Text Available We investigate the climatic impact of stratospheric ozone recovery (SOR, with a focus on the surface temperature change in atmosphere–slab ocean coupled climate simulations. We find that although SOR would cause significant surface warming (global mean: 0.2 K in a climate free of clouds and sea ice, it causes surface cooling (−0.06 K in the real climate. The results here are especially interesting in that the stratosphere-adjusted radiative forcing is positive in both cases. Radiation diagnosis shows that the surface cooling is mainly due to a strong radiative effect resulting from significant reduction of global high clouds and, to a lesser extent, from an increase in high-latitude sea ice. Our simulation experiments suggest that clouds and sea ice are sensitive to stratospheric ozone perturbation, which constitutes a significant radiative adjustment that influences the sign and magnitude of the global surface temperature change.

  16. A Simple Model of Fields Including the Strong or Nuclear Force and a Cosmological Speculation

    Directory of Open Access Journals (Sweden)

    David L. Spencer

    2016-10-01

    Full Text Available Reexamining the assumptions underlying the General Theory of Relativity and calling an object's gravitational field its inertia, and acceleration simply resistance to that inertia, yields a simple field model where the potential (kinetic energy of a particle at rest is its capacity to move itself when its inertial field becomes imbalanced. The model then attributes electromagnetic and strong forces to the effects of changes in basic particle shape. Following up on the model's assumption that the relative intensity of a particle's gravitational field is always inversely related to its perceived volume and assuming that all black holes spin, may create the possibility of a cosmic rebound where a final spinning black hole ends with a new Big Bang.

  17. 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.

  18. Human health and the water environment: using the DPSEEA framework to identify the driving forces of disease.

    Science.gov (United States)

    Gentry-Shields, Jennifer; Bartram, Jamie

    2014-01-15

    There is a growing awareness of global forces that threaten human health via the water environment. A better understanding of the dynamic between human health and the water environment would enable prediction of the significant driving forces and effective strategies for coping with or preventing them. This report details the use of the Driving Force-Pressure-State-Exposure-Effect-Action (DPSEEA) framework to explore the linkage between water-related diseases and their significant driving forces. The DPSEEA frameworks indicate that a select group of driving forces, including population growth, agriculture, infrastructure (dams and irrigation), and climate change, is at the root cause of key global disease burdens. Construction of the DPSEEA frameworks also allows for the evaluation of public health interventions. Sanitation was found to be a widely applicable and effective intervention, targeting the driver/pressure linkage of most of the water-related diseases examined. Ultimately, the DPSEEA frameworks offer a platform for constituents in both the health and environmental fields to collaborate and commit to a common goal targeting the same driving forces. © 2013.

  19. Modelling alongshore flow in a semi-enclosed lagoon strongly forced by tides and waves

    Science.gov (United States)

    Taskjelle, Torbjørn; Barthel, Knut; Christensen, Kai H.; Furaca, Noca; Gammelsrød, Tor; Hoguane, António M.; Nharreluga, Bilardo

    2014-08-01

    Alongshore flows strongly driven by tides and waves is studied in the context of a one-dimensional numerical model. Observations from field surveys performed in a semi-enclosed lagoon (1.7 km×0.2 km) outside Xai-Xai, Mozambique, are used to validate the model results. The model is able to capture most of the observed temporal variability of the current, but sea surface height tends to be overestimated at high tide, especially during high wave events. Inside the lagoon we observed a mainly uni-directional alongshore current, with speeds up to 1 ms-1. The current varies primarily with the tide, being close to zero near low tide, generally increasing during flood and decreasing during ebb. The observations revealed a local minimum in the alongshore flow at high tide, which the model was successful in reproducing. Residence times in the lagoon were calculated to be less than one hour with wave forcing dominating the flushing. At this beach a high number of drowning casualties have occurred, but no connection was found between them and strong current events in a simulation covering the period 2011-2012.

  20. Driving forces shaping advanced reactor designs: Near-term and long-term prospects

    International Nuclear Information System (INIS)

    Sholly, S.C.

    1990-01-01

    This paper explores the forces which have driven and which in the opinion of the author should be driving advanced reactor development programs. Four general driving forces are identified: cost, safety, environmental concerns, and non-proliferation concerns. It is suggested that the primary driving forces should be cost and safety concerns. It is suggested that advanced reactors need to demonstrate the following characteristics: (a) A design which explicitly accounts for severe accidents, including severe external events (not necessarily limited to contemporary design basis events) and which results in a frequency of severe core damage substantially lower than in current plants. The goal for the frequency of severe core damage should reflect a reasonable assurance that a severe core damage accident will not occur during the operating lifetime of a fleet' of such plants. (b) A design which explicitly accounts for severe accidents in terms of accident mitigation, resulting in a very low conditional likelihood of a substantial fission product release given a severe accident. (c) A design which utilizes near-passive and passive concepts (whose safety and reliability are demonstrable by experiment and/or full-scale test) for both accident prevention and accident mitigation to the maximum extent feasible. (d) A design which allows f a suitably long time between refueling outages, with a balance struck between refueling outage duration and refueling outage frequency so as to maximize availability and capacity factor. (e) A design which emphasizes modular construction and exceptional quality control. (f) A design which de emphasizes the importance of maintenance and human reliability more generally to assure that safety functions are performed with acceptable reliability, and to assure that passive safety characteristics are not compromised by design, manufacturing, or installation defects. It is further suggested that key factors in gaining public acceptance are the early

  1. Driving forces shaping advanced reactor designs: Near-term and long-term prospects

    Energy Technology Data Exchange (ETDEWEB)

    Sholly, S C [MHB Technical Associates, San Jose, CA (United States)

    1990-07-01

    This paper explores the forces which have driven and which in the opinion of the author should be driving advanced reactor development programs. Four general driving forces are identified: cost, safety, environmental concerns, and non-proliferation concerns. It is suggested that the primary driving forces should be cost and safety concerns. It is suggested that advanced reactors need to demonstrate the following characteristics: (a) A design which explicitly accounts for severe accidents, including severe external events (not necessarily limited to contemporary design basis events) and which results in a frequency of severe core damage substantially lower than in current plants. The goal for the frequency of severe core damage should reflect a reasonable assurance that a severe core damage accident will not occur during the operating lifetime of a fleet' of such plants. (b) A design which explicitly accounts for severe accidents in terms of accident mitigation, resulting in a very low conditional likelihood of a substantial fission product release given a severe accident. (c) A design which utilizes near-passive and passive concepts (whose safety and reliability are demonstrable by experiment and/or full-scale test) for both accident prevention and accident mitigation to the maximum extent feasible. (d) A design which allows f a suitably long time between refueling outages, with a balance struck between refueling outage duration and refueling outage frequency so as to maximize availability and capacity factor. (e) A design which emphasizes modular construction and exceptional quality control. (f) A design which de emphasizes the importance of maintenance and human reliability more generally to assure that safety functions are performed with acceptable reliability, and to assure that passive safety characteristics are not compromised by design, manufacturing, or installation defects. It is further suggested that key factors in gaining public acceptance are the early

  2. The Impact of Evolutionary Driving Forces on Human Complex Diseases: A Population Genetics Approach

    Directory of Open Access Journals (Sweden)

    Amr T. M. Saeb

    2016-01-01

    Full Text Available Investigating the molecular evolution of human genome has paved the way to understand genetic adaptation of humans to the environmental changes and corresponding complex diseases. In this review, we discussed the historical origin of genetic diversity among human populations, the evolutionary driving forces that can affect genetic diversity among populations, and the effects of human movement into new environments and gene flow on population genetic diversity. Furthermore, we presented the role of natural selection on genetic diversity and complex diseases. Then we reviewed the disadvantageous consequences of historical selection events in modern time and their relation to the development of complex diseases. In addition, we discussed the effect of consanguinity on the incidence of complex diseases in human populations. Finally, we presented the latest information about the role of ancient genes acquired from interbreeding with ancient hominids in the development of complex diseases.

  3. Robust 2-Qubit Gates in a Linear Ion Crystal Using a Frequency-Modulated Driving Force

    Science.gov (United States)

    Leung, Pak Hong; Landsman, Kevin A.; Figgatt, Caroline; Linke, Norbert M.; Monroe, Christopher; Brown, Kenneth R.

    2018-01-01

    In an ion trap quantum computer, collective motional modes are used to entangle two or more qubits in order to execute multiqubit logical gates. Any residual entanglement between the internal and motional states of the ions results in loss of fidelity, especially when there are many spectator ions in the crystal. We propose using a frequency-modulated driving force to minimize such errors. In simulation, we obtained an optimized frequency-modulated 2-qubit gate that can suppress errors to less than 0.01% and is robust against frequency drifts over ±1 kHz . Experimentally, we have obtained a 2-qubit gate fidelity of 98.3(4)%, a state-of-the-art result for 2-qubit gates with five ions.

  4. On the driving force for crack growth during thermal actuation of shape memory alloys

    Science.gov (United States)

    Baxevanis, T.; Parrinello, A. F.; Lagoudas, D. C.

    2016-04-01

    The effect of thermomechanically induced phase transformation on the driving force for crack growth in polycrystalline shape memory alloys is analyzed in an infinite center-cracked plate subjected to a thermal actuation cycle under mechanical load in plain strain. Finite element calculations are carried out to determine the mechanical fields near the static crack and the crack-tip energy release rate using the virtual crack closure technique. A substantial increase of the energy release rate - an order of magnitude for some material systems - is observed during the thermal cycle due to the stress redistribution induced by large scale phase transformation. Thus, phase transformation occurring due to thermal variations under mechanical load may result in crack growth if the crack-tip energy release rate reaches a material specific critical value.

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

    DEFF Research Database (Denmark)

    Bek-Pedersen, Erik; Gani, Rafiqul

    2004-01-01

    A new integrated framework for synthesis, design and operation of distillation-based separation schemes is presented here. This framework is based on the driving force approach, which provides a measure of the differences in chemical/physical properties between two co-existing phases...... in a separation unit. A set of algorithms has been developed within this framework for design of simple as well as complex distillation columns, for the sequencing of distillation trains, for the determination of appropriate conditions of operation and for retrofit of distillation columns. The main feature of all...... these algorithms is that they provide a simple "visual" method to obtain near-optimal solutions in terms of energy consumption without rigorous simulation and/or optimisation. Several illustrative examples highlighting the application of the integrated approach are also presented. (C) 2003 Published by Elsevier B.V....

  6. Driving forces: Motor vehicle trends and their implications for global warming, energy strategies, and transportation planning

    International Nuclear Information System (INIS)

    MacKenzie, J.J.; Walsh, M.P.

    1990-01-01

    Cars, trucks, and other vehicles have long been linked to smog and other urban pollution, but the part they play in the larger complex of atmospheric and energy ills that we now face is often overlooked. In Driving Forces: Motor Vehicle Trends and Their Implications for Global Warming, Energy Strategies, and Transportation Planning, James J. MacKenzie, senior associate in World Resources Institute's Program in Climate, Energy, and Pollution, and Michael P. Walsh, an international consultant on transportation and environmental issues, fill in this knowledge gap with new data and analyses. They spell out four policy shifts that can help hold the line on global warming: improve new-vehicle efficiency; make transportation more efficient; cut other greenhouse gas emissions; create the green car of the future. The report focuses especially on the US, which pioneered the automotive revolution and leads the world in oil imports and emissions

  7. Computational simulations of direct contact condensation as the driving force for water hammer

    International Nuclear Information System (INIS)

    Ceuca, Sabin-Cristian

    2015-01-01

    An analysis, based on Computer Simulations of the Direct Contact Condensation as the Driving Force for the Condensation Induced Water Hammer phenomenon is performed within this thesis. The goal of the work is to develop a mechanistic HTC model, with predictive capabilities for the simulation of horizontal or nearly horizontal two-phase ows with complex patterns including the e ect of interfacial heat and mass transfer. The newly developed HTC model was implemented into the system code ATHLET and into the CFD tools ANSYS CFX and OpenFOAM. Validation calculations have been performed for horizontal or nearly horizontal ows, where simulation results have been compared against the local measurement data such as void and temperature or area averaged data delivered by a wire mesh sensor.

  8. Greatest Happiness Principle in a Complex System: Maximisation versus Driving Force

    Directory of Open Access Journals (Sweden)

    Katalin Martinás

    2012-06-01

    Full Text Available From philosophical point of view, micro-founded economic theories depart from the principle of the pursuit of the greatest happiness. From mathematical point of view, micro-founded economic theories depart from the utility maximisation program. Though economists are aware of the serious limitations of the equilibrium analysis, they remain in that framework. We show that the maximisation principle, which implies the equilibrium hypothesis, is responsible for this impasse. We formalise the pursuit of the greatest happiness principle by the help of the driving force postulate: the volumes of activities depend on the expected wealth increase. In that case we can get rid of the equilibrium hypothesis and have new insights into economic theory. For example, in what extent standard economic results depend on the equilibrium hypothesis?

  9. Output Force Enhancement of Scratch Drive Actuator in Low-Voltage Region by Using Flexible Joint

    Directory of Open Access Journals (Sweden)

    Shawn CHEN

    2010-04-01

    Full Text Available Here a low-voltage scratch drive actuator (LVSDA is proposed by incorporating flexible joint into the conventional SDA to improve performance in low-voltage region. Experimental results show that, at the same total plate length of 80 mm and width of 65 mm, the proposed LVSDA can be actuated as low as 40 V, much lower than 80 V, the minimum required input voltage of the conventional SDA. From finite element analysis by CosmosWorks, yielding effect is found to be a critical factor. Before yielding, LVSDA can provide better performance than SDA at the same input voltage. However, the yielding stress in flexible joint would limit the achievable maximum output force in high-voltage region. By varying joint length, width, or location, LVSDA is shown to be operated in low-voltage region where the conventional SDA can not be operated, and can still provide comparable performance as SDA in high-voltage region.

  10. An analysis of the driving forces of CO2 emissions embodied in Japan-China trade

    International Nuclear Information System (INIS)

    Dong Yanli; Ishikawa, Masanobu; Liu Xianbing; Wang Can

    2010-01-01

    By using the latest China-Japan input-output data sets and the index decomposition analysis (IDA) approach, this article analyzes the driving forces of CO 2 emissions embodied in trade between the two countries during 1990-2000. We found that the growth of trade volume had a large influence on the increase of CO 2 emissions embodiments in bilateral trade. The dramatic decline in carbon intensity of the Chinese economy is a primary cause in offsetting CO 2 emissions exported from China to Japan over 1995-2000. We argue that a better understanding of the factors affecting CO 2 emissions embodied in international trade will assist in seeking more effective climate policies with wider participation in the post-Kyoto regime.

  11. Computational simulations of direct contact condensation as the driving force for water hammer

    Energy Technology Data Exchange (ETDEWEB)

    Ceuca, Sabin-Cristian

    2015-04-27

    An analysis, based on Computer Simulations of the Direct Contact Condensation as the Driving Force for the Condensation Induced Water Hammer phenomenon is performed within this thesis. The goal of the work is to develop a mechanistic HTC model, with predictive capabilities for the simulation of horizontal or nearly horizontal two-phase ows with complex patterns including the e ect of interfacial heat and mass transfer. The newly developed HTC model was implemented into the system code ATHLET and into the CFD tools ANSYS CFX and OpenFOAM. Validation calculations have been performed for horizontal or nearly horizontal ows, where simulation results have been compared against the local measurement data such as void and temperature or area averaged data delivered by a wire mesh sensor.

  12. Changing and Differentiated Urban Landscape in China: Spatiotemporal Patterns and Driving Forces.

    Science.gov (United States)

    Fang, Chuanglin; Li, Guangdong; Wang, Shaojian

    2016-03-01

    Urban landscape spatiotemporal change patterns and their driving mechanisms in China are poorly understood at the national level. Here we used remote sensing data, landscape metrics, and a spatial econometric model to characterize the spatiotemporal patterns of urban landscape change and investigate its driving forces in China between 1990 and 2005. The results showed that the urban landscape pattern has experienced drastic changes over the past 15 years. Total urban area has expanded approximately 1.61 times, with a 2.98% annual urban-growth rate. Compared to previous single-city studies, although urban areas are expanding rapidly, the overall fragmentation of the urban landscape is decreasing and is more irregular and complex at the national level. We also found a stair-stepping, urban-landscape changing pattern among eastern, central, and western counties. In addition, administrative level, urban size, and hierarchy have effects on the urban landscape pattern. We also found that a combination of landscape metrics can be used to supplement our understanding of the pattern of urbanization. The changes in these metrics are correlated with geographical indicators, socioeconomic factors, infrastructure variables, administrative level factors, policy factors, and historical factors. Our results indicate that the top priority should be strengthening the management of urban planning. A compact and congregate urban landscape may be a good choice of pattern for urban development in China.

  13. 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.

  14. Optical pulling and pushing forces exerted on silicon nanospheres with strong coherent interaction between electric and magnetic resonances.

    Science.gov (United States)

    Liu, Hongfeng; Panmai, Mingcheng; Peng, Yuanyuan; Lan, Sheng

    2017-05-29

    We investigated theoretically and numerically the optical pulling and pushing forces acting on silicon (Si) nanospheres (NSs) with strong coherent interaction between electric and magnetic resonances. We examined the optical pulling and pushing forces exerted on Si NSs by two interfering waves and revealed the underlying physical mechanism from the viewpoint of electric- and magnetic-dipole manipulation. As compared with a polystyrene (PS) NS, it was found that the optical pulling force for a Si NS with the same size is enlarged by nearly two orders of magnitude. In addition to the optical pulling force appearing at the long-wavelength side of the magnetic dipole resonance, very large optical pushing force is observed at the magnetic quadrupole resonance. The correlation between the optical pulling/pushing force and the directional scattering characterized by the ratio of the forward to backward scattering was revealed. More interestingly, it was found that the high-order electric and magnetic resonances in large Si NSs play an important role in producing optical pulling force which can be generated by not only s-polarized wave but also p-polarized one. Our finding indicates that the strong coherent interaction between the electric and magnetic resonances existing in nanoparticles with large refractive indices can be exploited to manipulate the optical force acting on them and the correlation between the optical force and the directional scattering can be used as guidance. The engineering and manipulation of optical forces will find potential applications in the trapping, transport and sorting of nanoparticles.

  15. Driving forces for home-based reablement; a qualitative study of older adults' experiences.

    Science.gov (United States)

    Hjelle, Kari Margrete; Tuntland, Hanne; Førland, Oddvar; Alvsvåg, Herdis

    2017-09-01

    As a result of the ageing population worldwide, there has been a growing international interest in a new intervention termed 'reablement'. Reablement is an early and time-limited home-based intervention with emphasis on intensive, goal-oriented and interdisciplinary rehabilitation for older adults in need of rehabilitation or at risk of functional decline. The aim of this qualitative study was to describe how older adults experienced participation in reablement. Eight older adults participated in semi-structured interviews. A qualitative content analysis was used as the analysis strategy. Four main themes emerged from the participants' experiences of participating in reablement: 'My willpower is needed', 'Being with my stuff and my people', 'The home-trainers are essential', and 'Training is physical exercises, not everyday activities'. The first three themes in particular reflected the participants' driving forces in the reablement process. Driving forces are intrinsic motivation in interaction with extrinsic motivation. Intrinsic motivation was based on the person's willpower and responsibility, and extrinsic motivation was expressed to be strengthened by being in one's home environment with 'own' people, as well as by the co-operation with the reablement team. The reablement team encouraged and supported the older adults to regain confidence in performing everyday activities as well as participating in the society. Our findings have practical significance for politicians, healthcare providers and healthcare professionals by contributing to an understanding of how intrinsic and extrinsic motivation influence reablement. Some persons need apparently more extrinsic motivational support also after the time-limited reablement period is completed. The municipal health and care services need to consider individualised follow-up programmes after the intensive reablement period in order to maintain the achieved skills to perform everyday activities and participate in

  16. The Key Driving Forces for Geo-Economic Relationships between China and ASEAN Countries

    Directory of Open Access Journals (Sweden)

    Shufang Wang

    2017-12-01

    Full Text Available With the rise of China and the implementation of the “21st Century Maritime Silk Road” strategy, research on geo-economics between China and ASEAN (Association of Southeast Asian Nations countries has become increasingly important. Current studies mainly focus on influencing factors, while there is little consideration about how these influencing factors act on geo-economic relationships. Therefore, this paper explores the key driving forces for geo-economic relationships between China and ASEAN countries by use of the structural equation modeling based on Partial Lease Squares. There are three main findings: (1 Economic factors have the greatest impact on geo-economic relationships and the total path effect is 0.778. Geo-location, geopolitics and geo-culture act on geo-economic relationships directly and indirectly. Their total path effects are 0.731, 0.645 and 0.513, respectively. (2 Indirect effects of geo-location, geopolitics and geo-culture impacting geo-economic relationships are far greater than direct effects. Geo-culture, in particular, has a vital mediating effect on geo-economic relationships. (3 Economic drivers promote geo-economic relationships through market, industrial policy, technical, network and benefit-sharing mechanisms. Political drivers improve geo-economic relationships through cooperation, negotiation, coordination and institutional mechanisms. Cultural drivers enhance geo-economic relationships through transmission mechanism. Location drivers facilitate geo-economic relationships through selection mechanism. We provide new insights on the geo-economic relationships through quantitative analysis and enrich the existing literature by revealing the key driving forces and mechanisms for geo-economic relationships.

  17. [Spatio-temporal change of sand-fixing function and its driving forces in desertification control ecological function area of Hunshandake, China].

    Science.gov (United States)

    Shen, Lu; Tian, Mei-rong; Gao, Ji-xi; Qian, Jin-ping

    2016-01-01

    Soil erosion is an important ecological and environmental problem in Hunshandake Desert, and the sand-fixing function determines the degree of ecological security in the entire region. In order to clarify the situation of windbreak and sand fixation in Hunshandake area, and to guide the prevention and treatment of desertification on regional scale, based on the meteorological and remote sensing data, this paper quantitatively analyzed the temporal and spatial pattern of windbreak and sand fixation ability between 2000-2010 by the revised wind erosion equation (RWEQ) model, meanwhile, the driving forces for each county ( or banner) in the functional zone were analyzed with the method of principal component analysis. The results showed that there was a fluctuation of the sand fixing capacity in Hunshandake over time, generally rendering a decline trend. The coniferous forest and grassland had strong windbreak and sand fixation capacity in unit area among the various land categories. In terms of spatial distribution, the windbreak and sand fixation function in western and southeastern region was weak and needed to be strengthened with ecological restoration efforts. Through the study of the social driving forces of each administrative region in the function zone, there were 3 main social driving forces of soil erosion in the administrative functions: the intensity of input-output, the level of economic development and the level of agriculture-husbandry development.

  18. NATURE AND DRIVING FORCES OF STRIKE MOVEMENT IN MOLDOVA IN LATE 1980S

    Directory of Open Access Journals (Sweden)

    Галина Евгеньевна Слободянюк

    2016-12-01

    Full Text Available The article discloses the nature and driving forces of the republican protest strike movement in Moldova in the period of perestroika reformsand its impact on the emergence and development of the civil conflict,which became the catalyst for the territorial division of the republic and the creation of the self-proclaimed Transnistrian statehood.In the article there is presented the analysis of the process of formationand activity of the strike movement. The author shows that the United Council of LabourUnionswas the initiator, organizer and the main acting force of the protest of the workers' movement, defending the civil and constitutional rights of the Russian-speaking population of the Transdnistrian region of the Moldavian SSR. The article allows getting an idea of the ways and methods of struggle of the working movement against the Soviet Moldavia nationalist representatives of the Popular front, which operated on the territory of the republic of Moldova. Particular attention is paid to the reasons of occurrence and major activities of the strike movement.Moreover, there are analyzed the consequences of these actions for the further political development of Moldova.

  19. EXTERNAL FORCES DRIVING CHANGE IN THE ROMANIAN SMALL AND MEDIUM SIZED ENTERPRISES

    Directory of Open Access Journals (Sweden)

    Roiban Roxana Nadina

    2012-07-01

    Full Text Available Change is a constant in everyday life confronting organizations to continuously adapt their strategy, structure, processes, and culture in order to survive and stay competitive on the market. Implementing organizational change is one of the most important skills required for managers and in the meantime the most difficult one. The forces driving change within an organization, that can be either external or internal, are those that propel a company forward towards change and in order to identify the need for change and make the proper changes, managers have to develop a tool that allows them to analyze how does the environment influence their business activities. A vision for change will clarify the directions in which the organization needs to move, starting from its current state and taking in consideration the existing opportunities and threats from the environment that allow to move to a future desired state. The purpose of this paper is to identify the concern for change in the Romanian small and medium sized enterprises by presenting and explaining the past and present influences of the main external forces that have determined the need for change in the last 3-5 years and to make recommendations about future possible changes that have to be performed by managers for a better harmonization with the environment. The research method used for this study is the interview on a sample that contains some of the most relevant SME’s from the western side of Romania, from different industries. We analyzed the main external forces that had an impact on the small and medium sized enterprises and how were they generating the need for organizational change, in order to see which present and future changes are required.

  20. Strong leadership and teamwork drive culture and performance change: Ohio State University Medical Center 2000-2006.

    Science.gov (United States)

    Sanfilippo, Fred; Bendapudi, Neeli; Rucci, Anthony; Schlesinger, Leonard

    2008-09-01

    Several characteristics of academic health centers have the potential to create high levels of internal conflict and misalignment that can pose significant leadership challenges. In September 2000, the positions of Ohio State University (OSU) senior vice president for health sciences, dean of the medical school, and the newly created position of chief executive officer of the OSU Medical Center (OSUMC) were combined under a single leader to oversee the OSUMC. This mandate from the president and trustees was modeled after top institutions with similar structures. The leader who assumed the role was tasked with improving OSUMC's academic, clinical, and financial performance. To achieve this goal, the senior vice president and his team employed the service value chain model of improving performance, based on the premise that leadership behavior/culture drives employee engagement/satisfaction, leading to customer satisfaction and improved organizational performance. Implementing this approach was a seven-step process: (1) selecting the right leadership team, (2) assessing the challenges and opportunities, (3) setting expectations for performance and leadership behavior, (4) aligning structures and functions, (5) engaging constituents, (6) developing leadership skills, and (7) defining strategies and tracking goals. The OSUMC setting during this period provides an observational case study to examine how these stepwise changes, instituted by strong leadership and teamwork, were able to make and implement sound decisions that drove substantial and measurable improvements in the engagement and satisfaction of faculty and staff; the satisfaction of students and patients; and academic, clinical, and financial performance.

  1. Solvent driving force ensures fast formation of a persistent and well-separated radical pair in plant cryptochrome

    DEFF Research Database (Denmark)

    Lüdemann, Gesa; Solov'yov, Ilia; Kubar, Tomás

    2015-01-01

    upon the electron transfer. This approach allows us to follow the time evolution of the electron transfer in an unbiased fashion and to reveal the molecular driving force which ensures fast electron transfer in cryptochrome guaranteeing formation of a persistent radical pair suitable...

  2. Blood pressure is the major driving force for plaque formation in aortic-constricted ApoE-/- mice

    DEFF Research Database (Denmark)

    Johansson, Maria E.; Wickman, Anna; Skøtt, Ole

    2006-01-01

    OBJECTIVE: Using an aortic constriction model in mice, we studied whether the increase in pressure or the activation of the renin-angiotensin system (RAS) and its main receptors is the main driving force for plaque progression. METHODS: Male ApoE mice underwent sham surgery or placement of a supr...

  3. Rising electricity consumption: Driving forces and consequences. The case of rural Zanzibar

    Energy Technology Data Exchange (ETDEWEB)

    Winther, Tanja [Centre for Development and the Environment (SUM), Univ. of Oslo (Norway)

    2007-07-01

    The paper addresses the current, rising electricity consumption in the southern, rural locality of Zanzibar and seeks to account for the range of driving forces behind people's changed practices. The author argues that these forces are, on the one hand, determined by the availability of new technologies and through global and national institutions and influences such as Islam, commercials and changes in the governmental sector (health, education). On the other hand, the paper explores the way such influences interplay with the internal dynamics related to increasing consumption. Through an analysis of the particular character and dynamics of social and cultural life in this region, the author explains why some practices are less likely to change than other practices. For example, people in Zanzibar keep electricity (freezers and stoves) at a distance from their food. By contrast, electric light is perceived as intimately related to education, as illustrated when school children are sent to school for night classes before important exams. To which extent may general approaches to the study of energy consumption draw on this empirical case from Zanzibar? In other contexts, the patterns of people's electricity use certainly differ. In terms of sustainable energy policies, each locality has a particular set of challenges and goals, which to varying degree may be related to poverty reduction and concern for the environment. Methodologically, however, the author argues that the phenomenon of energy consumption may be studied and understood within the same framework of analysis; one that pays attention to both external and internal dynamics, the material and social aspects of technologies and the importance of power relations, gender and negotiations.

  4. Gravity, Special Relativity, and the Strong Force A Bohr-Einstein-de Broglie Model for the Formation of Hadrons

    CERN Document Server

    Vayenas, Constantinos G

    2012-01-01

    This book shows that the strong interaction forces, which keep hadrons and nuclei together, are relativistic gravitational forces exerted between very small particles in the mass range of neutrinos. First, this book considers the problematic motion of two charged particles under the influence of electrostatic and gravitational forces only, which shows that bound states are formed by following the same semi-classical methodology used by Bohr to describe the H atom. This approach is also coupled with Newton's gravitational law and with Einstein's special relativity. The results agree with experi

  5. 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.

  6. Climatic driving forces in inter-annual variation of global FPAR

    Science.gov (United States)

    Peng, Dailiang; Liu, Liangyun; Yang, Xiaohua; Zhou, Bin

    2012-09-01

    Fraction of Absorbed Photosynthetically Active Radiation (FPAR) characterizes vegetation canopy functioning and its energy absorption capacity. In this paper, we focus on climatic driving forces in inter-annual variation of global FPAR from 1982 to 2006 by Global Historical Climatology Network (GHCN-Monthly) data. Using FPAR-Simple Ratio Vegetation Index (SR) relationship, Advanced Very High Resolution Radiometer (AVHRR) Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index (NDVI) was used to estimate FPAR at the global scale. The correlation between inter-annual variation of FPAR and temperature, precipitation derived from GHCN-Monthly was examined, during the periods of March-May (MAM), June-August (JJA), September-November (SON), and December-February (DJF) over from 1982 to 2006. The analysis of climatic influence on global FPAR revealed the significant correlation with temperature and precipitation in some meteorological stations area, and a more significant correlation with precipitation was found than which with temperature. Some stations in the regions between 30° N and 60° N and around 30° S in South America, where the annual FPAR variation showed a significant positive correlation with temperature (P forest of Africa and Amazon during the dry season of JJA and SON.

  7. Force Sensitive Handles and Capacitive Touch Sensor for Driving a Flexible Haptic-Based Immersive System

    Directory of Open Access Journals (Sweden)

    Umberto Cugini

    2013-10-01

    Full Text Available In this article, we present an approach that uses both two force sensitive handles (FSH and a flexible capacitive touch sensor (FCTS to drive a haptic-based immersive system. The immersive system has been developed as part of a multimodal interface for product design. The haptic interface consists of a strip that can be used by product designers to evaluate the quality of a 3D virtual shape by using touch, vision and hearing and, also, to interactively change the shape of the virtual object. Specifically, the user interacts with the FSH to move the virtual object and to appropriately position the haptic interface for retrieving the six degrees of freedom required for both manipulation and modification modalities. The FCTS allows the system to track the movement and position of the user’s fingers on the strip, which is used for rendering visual and sound feedback. Two evaluation experiments are described, which involve both the evaluation and the modification of a 3D shape. Results show that the use of the haptic strip for the evaluation of aesthetic shapes is effective and supports product designers in the appreciation of the aesthetic qualities of the shape.

  8. Force sensitive handles and capacitive touch sensor for driving a flexible haptic-based immersive system.

    Science.gov (United States)

    Covarrubias, Mario; Bordegoni, Monica; Cugini, Umberto

    2013-10-09

    In this article, we present an approach that uses both two force sensitive handles (FSH) and a flexible capacitive touch sensor (FCTS) to drive a haptic-based immersive system. The immersive system has been developed as part of a multimodal interface for product design. The haptic interface consists of a strip that can be used by product designers to evaluate the quality of a 3D virtual shape by using touch, vision and hearing and, also, to interactively change the shape of the virtual object. Specifically, the user interacts with the FSH to move the virtual object and to appropriately position the haptic interface for retrieving the six degrees of freedom required for both manipulation and modification modalities. The FCTS allows the system to track the movement and position of the user's fingers on the strip, which is used for rendering visual and sound feedback. Two evaluation experiments are described, which involve both the evaluation and the modification of a 3D shape. Results show that the use of the haptic strip for the evaluation of aesthetic shapes is effective and supports product designers in the appreciation of the aesthetic qualities of the shape.

  9. The Driving Forces of Cultural Complexity : Neanderthals, Modern Humans, and the Question of Population Size.

    Science.gov (United States)

    Fogarty, Laurel; Wakano, Joe Yuichiro; Feldman, Marcus W; Aoki, Kenichi

    2017-03-01

    The forces driving cultural accumulation in human populations, both modern and ancient, are hotly debated. Did genetic, demographic, or cognitive features of behaviorally modern humans (as opposed to, say, early modern humans or Neanderthals) allow culture to accumulate to its current, unprecedented levels of complexity? Theoretical explanations for patterns of accumulation often invoke demographic factors such as population size or density, whereas statistical analyses of variation in cultural complexity often point to the importance of environmental factors such as food stability, in determining cultural complexity. Here we use both an analytical model and an agent-based simulation model to show that a full understanding of the emergence of behavioral modernity, and the cultural evolution that has followed, depends on understanding and untangling the complex relationships among culture, genetically determined cognitive ability, and demographic history. For example, we show that a small but growing population could have a different number of cultural traits from a shrinking population with the same absolute number of individuals in some circumstances.

  10. Casualisation of the nursing workforce in Australia: driving forces and implications.

    Science.gov (United States)

    Creegan, Reta; Duffield, Christine; Forrester, Kim

    2003-01-01

    This article provides an overview of the extent of casualisation of the nursing workforce in Australia, focusing on the impact for those managing the system. The implications for nurse managers in particular are considerable in an industry where service demand is difficult to control and where individual nurses are thought to be increasingly choosing to work casually. While little is known of the reasons behind nurses exercising their preference for casual work arrangements, some reasons postulated include visa status (overseas trained nurses on holiday/working visas); permanent employees taking on additional shifts to increase their income levels; and those who elect to work under casual contracts for lifestyle reasons. Unknown is the demography of the casual nursing workforce, how these groups are distributed within the workforce, and how many contracts of employment they have across the health service--either through privately managed nursing agencies or hospital managed casual pools. A more detailed knowledge of the forces driving the decisions of this group is essential if health care organisations are to equip themselves to manage this changing workforce and maintain a standard of patient care that is acceptable to the community.

  11. Driving forces of organic carbon spatial distribution in the tropical seascape

    Science.gov (United States)

    Gillis, L. G.; Belshe, F. E.; Ziegler, A. D.; Bouma, T. J.

    2017-02-01

    An important ecosystem service of tropical coastal vegetation including seagrass beds and mangrove forests is their ability to accumulate carbon. Here we attempt to establish the driving forces for the accumulation of surface organic carbon in southern Thailand coastal systems. Across 12 sites we found that in line with expectations, seagrass beds (0.6 ± 0.09%) and mangrove forests (0.9 ± 0.3%) had higher organic carbon in the surface (top 5 cm) sediment than un-vegetated mudflats (0.4 ± 0.04%). Unexpectedly, however, mangrove forests in this region retained organic carbon, rather than outwell it, under normal tidal conditions. No relationship was found between organic carbon and substrate grain size. The most interesting finding of our study was that climax and pioneer seagrass species retained more carbon than mixed-species meadows, suggesting that plant morphology and meadow characteristics can be important factors in organic carbon accumulation. Insights such as these are important in developing carbon management strategies involving coastal ecosystems such as offsetting of carbon emissions. The ability of tropical coastal vegetation to sequester carbon is an important aspect for valuing the ecosystems. Our results provide some initial insight into the factors affecting carbon sequestration in these ecosystems, but also highlight the need for further research on a global scale.

  12. Study on anti-seismic test of control rod driving system suspended by magnetic force

    International Nuclear Information System (INIS)

    Zhang Zhihua; Qian Dazhi; Xu Xianqi; Huang Hongwen; Zhang Zhengming; Wu Xinxin; Hu Xiao

    2012-01-01

    To verify the stability, reliability and security function in extreme conditions, the anti-seismic test of control rod drive line was conducted. Drop-time of control rod drive line in different earthquake intensities was got. The response and strain values of control rod drive line acceleration on SL-1, SL-2 level were measured. Safety functions of control rod drive line were validated in different work conditions. Anti-seismic test data shows that the driving system can keep the structure's integrality and realize operation function under OBE and SSE. (authors)

  13. Exact results for the behavior of the thermodynamic Casimir force in a model with a strong adsorption

    Science.gov (United States)

    Dantchev, Daniel M.; Vassilev, Vassil M.; Djondjorov, Peter A.

    2016-09-01

    When massless excitations are limited or modified by the presence of material bodies one observes a force acting between them generally called Casimir force. Such excitations are present in any fluid system close to its true bulk critical point. We derive exact analytical results for both the temperature and external ordering field behavior of the thermodynamic Casimir force within the mean-field Ginzburg-Landau Ising type model of a simple fluid or binary liquid mixture. We investigate the case when under a film geometry the boundaries of the system exhibit strong adsorption onto one of the phases (components) of the system. We present analytical and numerical results for the (temperature-field) relief map of the force in both the critical region of the film close to its finite-size or bulk critical points as well as in the capillary condensation regime below but close to the finite-size critical point.

  14. Large methane releases lead to strong aerosol forcing and reduced cloudiness

    DEFF Research Database (Denmark)

    Kurten, T.; Zhou, L.; Makkonen, R.

    2011-01-01

    The release of vast quantities of methane into the atmosphere as a result of clathrate destabilization is a potential mechanism for rapid amplification of global warming. Previous studies have calculated the enhanced warming based mainly on the radiative effect of the methane itself, with smaller...... is predicted to significantly decrease hydroxyl radical (OH) concentrations, while moderately increasing ozone (O-3). These changes lead to a 70% increase in the atmospheric lifetime of methane, and an 18% decrease in global mean cloud droplet number concentrations (CDNC). The CDNC change causes a radiative...... forcing that is comparable in magnitude to the long-wave radiative forcing ("enhanced greenhouse effect") of the added methane. Together, the indirect CH4-O-3 and CH4-OHaerosol forcings could more than double the warming effect of large methane increases. Our findings may help explain the anomalously...

  15. How metal films de-wet substrates-identifying the kinetic pathways and energetic driving forces

    International Nuclear Information System (INIS)

    McCarty, Kevin F; Hamilton, John C; Thuermer, Konrad; Jones, Frank; Talin, A Alec; Bartelt, Norman C; Sato, Yu; K Schmid, Andreas; Saa, Angela; Figuera, Juan de la; Stumpf, Roland

    2009-01-01

    We study how single-crystal chromium films of uniform thickness on W(110) substrates are converted to arrays of three-dimensional (3D) Cr islands during annealing. We use low-energy electron microscopy (LEEM) to directly observe a kinetic pathway that produces trenches that expose the wetting layer. Adjacent film steps move simultaneously uphill and downhill relative to the staircase of atomic steps on the substrate. This step motion thickens the film regions where steps advance. Where film steps retract, the film thins, eventually exposing the stable wetting layer. Since our analysis shows that thick Cr films have a lattice constant close to bulk Cr, we propose that surface and interface stress provide a possible driving force for the observed morphological instability. Atomistic simulations and analytic elastic models show that surface and interface stress can cause a dependence of film energy on thickness that leads to an instability to simultaneous thinning and thickening. We observe that de-wetting is also initiated at bunches of substrate steps in two other systems, Ag/W(110) and Ag/Ru(0001). We additionally describe how Cr films are converted into patterns of unidirectional stripes as the trenches that expose the wetting layer lengthen along the W[001] direction. Finally, we observe how 3D Cr islands form directly during film growth at elevated temperature. The Cr mesas (wedges) form as Cr film steps advance down the staircase of substrate steps, another example of the critical role that substrate steps play in 3D island formation.

  16. Analysis of the Driving Forces in Vegetation Variation in the Grain for Green Program Region, China

    Directory of Open Access Journals (Sweden)

    Wang Hao

    2017-10-01

    Full Text Available The Chinese government introduced six ecological restoration programs to improve its natural environment. Although these programs have proven successful in improving local environmental conditions, some studies have questioned their effectiveness when regions suffer from extreme weather conditions. Using the Grain for Green Program (GGP region as a study area, we estimated vegetation activities in the GGP region from 2000 to 2010 to clarify the trends in vegetation growth and their driving forces. The results showed that: (1 vegetation activities improved in the GGP region during 2000-2010, with 58.94% of the area showing an increased trend in the NDVI (normalized difference vegetation index; (2 26.33% of the increased vegetation was caused by human interference, and 11.61% by climate variation, human activity was the dominant cause, and resulted in 54.68% of the degradation compared to 4.74% from climate change; and, (3 the contribution of different land use types to the NDVI interannual variations showed that high contribution regions were focused in the arid and semiarid areas, where the vegetation growth is associated with variations in recipitation and temperature. However, conversions between farmland and grassland or forest had a significant effect on the change in the NDVI trend. Therefore, although climate conditions can affect vegetation growth, human activities are more important in vegetation changes, and appropriate human activities would contribute to its continual improvement. Hence, we recommend establishing an assessment and scientific management mechanism for eco-risks in the design and management of ecosystem restoration programs.

  17. A study on the fundamental mechanism and the evolutionary driving forces behind aerobic fermentation in yeast.

    Science.gov (United States)

    Hagman, Arne; Piškur, Jure

    2015-01-01

    Baker's yeast Saccharomyces cerevisiae rapidly converts sugars to ethanol and carbon dioxide at both anaerobic and aerobic conditions. The later phenomenon is called Crabtree effect and has been described in two forms, long-term and short-term effect. We have previously studied under fully controlled aerobic conditions forty yeast species for their central carbon metabolism and the presence of long-term Crabtree effect. We have also studied ten steady-state yeast cultures, pulsed them with glucose, and followed the central carbon metabolism and the appearance of ethanol at dynamic conditions. In this paper we analyzed those wet laboratory data to elucidate possible mechanisms that determine the fate of glucose in different yeast species that cover approximately 250 million years of evolutionary history. We determine overflow metabolism to be the fundamental mechanism behind both long- and short-term Crabtree effect, which originated approximately 125-150 million years ago in the Saccharomyces lineage. The "invention" of overflow metabolism was the first step in the evolution of aerobic fermentation in yeast. It provides a general strategy to increase energy production rates, which we show is positively correlated to growth. The "invention" of overflow has also simultaneously enabled rapid glucose consumption in yeast, which is a trait that could have been selected for, to "starve" competitors in nature. We also show that glucose repression of respiration is confined mainly among S. cerevisiae and closely related species that diverged after the whole genome duplication event, less than 100 million years ago. Thus, glucose repression of respiration was apparently "invented" as a second step to further increase overflow and ethanol production, to inhibit growth of other microbes. The driving force behind the initial evolutionary steps was most likely competition with other microbes to faster consume and convert sugar into biomass, in niches that were semi-anaerobic.

  18. A study on the fundamental mechanism and the evolutionary driving forces behind aerobic fermentation in yeast.

    Directory of Open Access Journals (Sweden)

    Arne Hagman

    Full Text Available Baker's yeast Saccharomyces cerevisiae rapidly converts sugars to ethanol and carbon dioxide at both anaerobic and aerobic conditions. The later phenomenon is called Crabtree effect and has been described in two forms, long-term and short-term effect. We have previously studied under fully controlled aerobic conditions forty yeast species for their central carbon metabolism and the presence of long-term Crabtree effect. We have also studied ten steady-state yeast cultures, pulsed them with glucose, and followed the central carbon metabolism and the appearance of ethanol at dynamic conditions. In this paper we analyzed those wet laboratory data to elucidate possible mechanisms that determine the fate of glucose in different yeast species that cover approximately 250 million years of evolutionary history. We determine overflow metabolism to be the fundamental mechanism behind both long- and short-term Crabtree effect, which originated approximately 125-150 million years ago in the Saccharomyces lineage. The "invention" of overflow metabolism was the first step in the evolution of aerobic fermentation in yeast. It provides a general strategy to increase energy production rates, which we show is positively correlated to growth. The "invention" of overflow has also simultaneously enabled rapid glucose consumption in yeast, which is a trait that could have been selected for, to "starve" competitors in nature. We also show that glucose repression of respiration is confined mainly among S. cerevisiae and closely related species that diverged after the whole genome duplication event, less than 100 million years ago. Thus, glucose repression of respiration was apparently "invented" as a second step to further increase overflow and ethanol production, to inhibit growth of other microbes. The driving force behind the initial evolutionary steps was most likely competition with other microbes to faster consume and convert sugar into biomass, in niches that

  19. A drastic reorganization of industry in the world.What is the driving force

    Directory of Open Access Journals (Sweden)

    Shinji Naruo

    2010-05-01

    Full Text Available The purpose of this paper is to show the method and model to analyze the driving force to reorganize the industry. Due to the global economy, many large scale M&A and affiliations are happening in the world. The business alliance and integration are happening in the advanced countries, the transition countries, and the developing countries. There are some factors to impact the reorganization of industry. One is government policy. Another is the market economy. The government has the industrial policy. It guides and leads the industrial structure of the country. Advanced countries had experienced the advancement of industrial structure. On the process of industrial structure advancement, the country improved national income (GNP. Through the process, the enterprise in the industry had experienced integration and separation in the industry. The theory of industrial structure supports the framework of this approach.On the other hand, the market economy also had influenced to the reorganization of industry. Business cycle, competition, and innovation had influenced the reorganization of industry. In capitalism, the shareholder of the company pushes the company to maximize the profit. The shareholder’s pressure could influence the decision of M&A.The theory of industrial organization supports the framework of this approach.The enterprise is in the business environment. Top management of the company is responsible to make a decision to merge or acquire the company. However, the decision is affected by other factors out of business environment. The shareholder influenced the individual enterprise decision. The government policy influenced the industrial structure. This could impose the enterprise to accept the amalgamation in the industry.Both of two influence the reorganization of industry.

  20. Directed motion of spheres induced by unbiased driving forces in viscous fluids beyond the Stokes' law regime

    Science.gov (United States)

    Casado-Pascual, Jesús

    2018-03-01

    The emergence of directed motion is investigated in a system consisting of a sphere immersed in a viscous fluid and subjected to time-periodic forces of zero average. The directed motion arises from the combined action of a nonlinear drag force and the applied driving forces, in the absence of any periodic substrate potential. Necessary conditions for the existence of such directed motion are obtained and an analytical expression for the average terminal velocity is derived within the adiabatic approximation. Special attention is paid to the case of two mutually perpendicular forces with sinusoidal time dependence, one with twice the period of the other. It is shown that, although neither of these two forces induces directed motion when acting separately, when added together, the resultant force generates directed motion along the direction of the force with the shortest period. The dependence of the average terminal velocity on the system parameters is analyzed numerically and compared with that obtained using the adiabatic approximation. Among other results, it is found that, for appropriate parameter values, the direction of the average terminal velocity can be reversed by varying the forcing strength. Furthermore, certain aspects of the observed phenomenology are explained by means of symmetry arguments.

  1. Seasonal changes and driving forces of inflow and outflow through the Bohai Strait

    Science.gov (United States)

    Zhang, Zhixin; Qiao, Fangli; Guo, Jingsong; Guo, Binghuo

    2018-02-01

    This work focuses on analyzing seasonal variation of inflow and outflow through the Bohai Strait that greatly affect the marine environment in the Bohai Sea, using observational data including sea bed mounted acoustic Doppler current profiler currents, CTD salinity data on deck, sea level anomalies of coastal tide gauge stations, and climatological monthly sea level anomalies from Archiving, Validation and Interpretation of Satellite Oceanographic data. Our results show three patterns of outflow and inflow through the Bohai Strait. The first is such that outflow and inflow occur respectively in the southern and northern parts of the strait, as in the traditional understanding. Our results suggest that this pattern occurs only in autumn and winter. Beginning in late September, Ekman currents driven by the northwesterly monsoon carry Bohai Sea water that piles up in the southern part of that sea and then exits eastward to the Yellow Sea. In this process, the pressure and current fields are continuously adjusted, until a quasi balance state between wind stress, Coriolis force and pressure gradient force is reached in winter. Inflow with a compensating property through the northern channel is close to the outflow through the southern channel in winter. The second pattern is a single inflow in spring, and the current and pressure fields are in adjustment. In early spring, the northwesterly monsoon ceases, Yellow Sea water enters the Bohai Sea under the pressure gradient force. With southeasterly monsoon establishment and strengthening, northern Yellow Sea water continually flows into the Bohai Sea and causes sea level rise northward. In the third pattern, outflow is much greater than inflow in summer. The currents run eastward in the central Bohai Sea and then enter the northern Yellow Sea through the northern channel and upper layer of the southern channel, while a westward current with a compensating property enters via the lower layer of the southern channel. Larger

  2. Sector trends and driving forces of global energy use and greenhouse gas emissions: focus in industry and buildings

    Energy Technology Data Exchange (ETDEWEB)

    Price, Lynn; Worrell, Ernst; Khrushch, Marta

    1999-09-01

    Disaggregation of sectoral energy use and greenhouse gas emissions trends reveals striking differences between sectors and regions of the world. Understanding key driving forces in the energy end-use sectors provides insights for development of projections of future greenhouse gas emissions. This report examines global and regional historical trends in energy use and carbon emissions in the industrial, buildings, transport, and agriculture sectors, with a more detailed focus on industry and buildings. Activity and economic drivers as well as trends in energy and carbon intensity are evaluated. The authors show that macro-economic indicators, such as GDP, are insufficient for comprehending trends and driving forces at the sectoral level. These indicators need to be supplemented with sector-specific information for a more complete understanding of future energy use and greenhouse gas emissions.

  3. Differences in Pattern and Driving Forces between Urban and Rural Settlements in the Coastal Region of Ningbo, China

    Directory of Open Access Journals (Sweden)

    Mingxing Chen

    2014-04-01

    Full Text Available Rapid urbanization on the coast of China has attracted much attention. The objective of this study was to explore the differences in dynamics and related driving forces between urban and rural settlements. Applying the quantitative method, we demonstrate that substantial heterogeneity in settlement growth, landscape pattern metrics, change, land sources and driving forces is exhibited across the different types of urban and rural settlements. The spatial growth of urban settlements is dominated by in situ expansion, while rural settlements tend to be scattered and shrinking rapidly. The sprawl of human settlements has mainly occupied farm land, but reclamation projects are increasingly becoming important land sources for urban settlements. Local government has played a critical role in urban settlements, while the expansion of rural settlements is mainly driven by individual choice and village collective organizations. Such differences may account for differential options for the management of human settlements scientifically.

  4. Deformation-induced martensitic transformation in a 201 austenitic steel: The synergy of stacking fault energy and chemical driving force

    Energy Technology Data Exchange (ETDEWEB)

    Moallemi, M., E-mail: m.moallemi@ma.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Kermanpur, A. [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Najafizadeh, A. [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Fould Institute of Technology, Fouladshahr, Isfahan, 8491663763 (Iran, Islamic Republic of); Rezaee, A.; Baghbadorani, H. Samaei; Nezhadfar, P. Dastranjy [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

    2016-01-20

    The present study deals with the correlation of stacking fault energy's synergy and driving force in the formation of deformation-induced martensitic transformation in a 201 austenitic stainless steel. The fraction of deformation-induced martensite was characterized by means of X-ray diffraction and magnetic induction techniques. The kinetics of the martensite formation versus applied strain was evaluated through the sigmoidal model. It was shown that the volume fraction of ά-martensite is closely related to the driving force/SFE ratio of the alloy. The results also showed that the martensite content is similar in both XRD and magnetic methods and the applied sigmoidal model was consistent with the obtained experimental data.

  5. Sector trends and driving forces of global energy use and greenhouse gas emissions: focus in industry and buildings

    International Nuclear Information System (INIS)

    Price, Lynn; Worrell, Ernst; Khrushch, Marta

    1999-01-01

    Disaggregation of sectoral energy use and greenhouse gas emissions trends reveals striking differences between sectors and regions of the world. Understanding key driving forces in the energy end-use sectors provides insights for development of projections of future greenhouse gas emissions. This report examines global and regional historical trends in energy use and carbon emissions in the industrial, buildings, transport, and agriculture sectors, with a more detailed focus on industry and buildings. Activity and economic drivers as well as trends in energy and carbon intensity are evaluated. The authors show that macro-economic indicators, such as GDP, are insufficient for comprehending trends and driving forces at the sectoral level. These indicators need to be supplemented with sector-specific information for a more complete understanding of future energy use and greenhouse gas emissions

  6. Uncovering driving forces on greenhouse gas emissions in China’ aluminum industry from the perspective of life cycle analysis

    International Nuclear Information System (INIS)

    Liu, Zhe; Geng, Yong; Adams, Michelle; Dong, Liang; Sun, Lina; Zhao, Jingjing; Dong, Huijuan; Wu, Jiao; Tian, Xu

    2016-01-01

    Highlights: • Energy-related GHG emission trajectories, features and driving forces of CAI are analyzed from the perspective of LCA. • CAI experienced a rapid growth of energy-related GHG emissions from 2004 to 2013. • Energy-scale effect is the main driving force for energy-related GHG emissions increase in CAI. • Construction and transportation-related activities account for more than 40% of the total embodied emissions. • Policy implications such as developing secondary aluminum industry, improving energy mix etc, are raised. - Abstract: With the rapid growth of aluminum production, reducing greenhouse gas (GHG) emissions in China’s aluminum industry (CAI) is posing a significant challenge. In this study, the energy-related GHG emission trajectories, features and driving forces of CAI are analyzed from the perspective of life cycle analysis (LCA) from 2004 to 2013. Results indicate that CAI experienced a rapid growth of energy-related GHG emissions with an average annual growth of 28.5 million tons CO_2e from 2004 to 2013. Energy-scale effect is the main driving force for energy-related GHG emissions increase in CAI, while emission-factor effect of secondary aluminum production plays a marginal effect. Construction and transportation-related activities account for the bulk of the embodied emissions, accounting for more than 40% of the total embodied emissions from CAI. Policy implications for GHG mitigation within the CAI, such as developing secondary aluminum industry, improving energy mix and optimizing resource efficiency of production, are raised.

  7. Meeting the challenges of the new energy industry: The driving forces facing electric power generators and the natural gas industry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The proceedings of the IGT national conference on meeting the challenges of the New Energy Industry: The driving forces facing Electric Power Generators and the Natural Gas Industry are presented. The conference was held June 19-21, 1995 at the Ambassador West Hotel in Downtown Chicago, Illinois. A separate abstract and indexing for each of the 18 papers presented for inclusion in the Energy Science and Technology Database.

  8. The Driving Forces for the Practice of Strategic Planning in SMEs: Evidence from Harare Metropolitan Province, Zimbabwe

    OpenAIRE

    Maxwell Sandada; Raynold Tinomudaishe Chikwama

    2016-01-01

    Despite Zimbabwe sharing with the rest of the world, the notion that SMEs are the impeccable engines to economic revival, growth and development, many of the nation`s SMEs are plagued with high failure rates. Previous studies carried out in most foreign countries suggested that the high failure rate of SMEs was attributable to lack of strategic planning among a host of other factors. Against this backdrop, the purpose of this study was to examine the driving forces for the practic...

  9. Meeting the challenges of the new energy industry: The driving forces facing electric power generators and the natural gas industry

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    The proceedings of the IGT national conference on meeting the challenges of the New Energy Industry: The driving forces facing Electric Power Generators and the Natural Gas Industry are presented. The conference was held June 19-21, 1995 at the Ambassador West Hotel in Downtown Chicago, Illinois. A separate abstract and indexing for each of the 18 papers presented for inclusion in the Energy Science and Technology Database

  10. Measuring Risky Driving Behavior Using an mHealth Smartphone App: Development and Evaluation of gForce

    Science.gov (United States)

    Dave, Amisha D; Espey, Benjamin G; Stanley, Sean T; Garmendia, Marcial A; Pursley, Randall; Ehsani, Johnathon P; Simons-Morton, Bruce G; Pohida, Thomas J

    2018-01-01

    Background Naturalistic driving studies, designed to objectively assess driving behavior and outcomes, are conducted by equipping vehicles with dedicated instrumentation (eg, accelerometers, gyroscopes, Global Positioning System, and cameras) that provide continuous recording of acceleration, location, videos, and still images for eventual retrieval and analyses. However, this research is limited by several factors: the cost of equipment installation; management and storage of the large amounts of data collected; and data reduction, coding, and analyses. Modern smartphone technology includes accelerometers built into phones, and the vast, global proliferation of smartphones could provide a possible low-cost alternative for assessing kinematic risky driving. Objective We evaluated an in-house developed iPhone app (gForce) for detecting elevated g-force events by comparing the iPhone linear acceleration measurements with corresponding acceleration measurements obtained with both a custom Android app and the in-vehicle miniDAS data acquisition system (DAS; Virginia Tech Transportation Institute). Methods The iPhone and Android devices were dashboard-mounted in a vehicle equipped with the DAS instrumentation. The experimental protocol consisted of driving maneuvers on a test track, such as cornering, braking, and turning that were performed at different acceleration levels (ie, mild, moderate, or hard). The iPhone gForce app recorded linear acceleration (ie, gravity-corrected). The Android app recorded gravity-corrected and uncorrected acceleration measurements, and the DAS device recorded gravity-uncorrected acceleration measurements. Lateral and longitudinal acceleration measures were compared. Results The correlation coefficients between the iPhone and DAS acceleration measurements were slightly lower compared to the correlation coefficients between the Android and DAS, possibly due to the gravity correction on the iPhone. Averaging the correlation coefficients for

  11. Driving force of PCMI failure under reactivity initiated accident conditions and influence of hydrogen embrittlement on failure limit

    International Nuclear Information System (INIS)

    Tomiyasu, Kunihiko; Sugiyama, Tomoyuki; Nakamura, Takehiko; Fuketa, Toyoshi

    2005-09-01

    In order to clarify the driving force of PCMI (Pellet/Cladding Mechanical Interaction) failure on high burnup fuels and to investigate the influence of hydrogen embrittlement on failure limit under RIA (Reactivity Initiated Accident) conditions, RIA-simulation experiments were performed on fresh fuel rods in the NSRR (Nuclear Safety Research Reactor). The driving force of PCMI was restricted only to thermal expansion of pellet by using fresh UO 2 pellets. Fresh claddings were pre-hydrided to simulate hydrogen absorption of high burnup fuel rods. In seven experiments out of fourteen, test rods resulted in PCMI failure, which has been observed in the NSRR tests on high burnup PWR fuels, in terms of the transient behavior and the fracture configuration. This indicates that the driving force of PCMI failure is sufficiently explained with thermal expansion of pellet and a contribution of fission gas on it is small. A large number of incipient cracks were generated in the outer surface of the cladding even on non-failed fuel rods, and they stopped at the boundary between hydride rim, which was a hydride layer localized in the periphery of the cladding, and metallic layer. It suggests that the integrity of the metallic layer except for the hydride rim has particular importance for failure limit. Fuel enthalpy at failure correlates with the thickness of hydride rim, and tends to decrease with thicker hydride layer. (author)

  12. Quantifying the Driving Forces of Informal Urbanization in the Western Part of the Greater Cairo Metropolitan Region

    Directory of Open Access Journals (Sweden)

    Taher Osman

    2016-06-01

    Full Text Available This paper discusses the driving forces (DFs of informal urbanization (IU in the greater Cairo metropolitan region (GCMR using the Analytic Hierarchy Process (AHP. The IU patterns in the GCMR have been extremely influenced by seven DFs: geographical characteristics, availability of life facilities, economic incentives, land demand and supply, population increase, administrative function, and development plans. This research found that these forces vary significantly in how they influence urban growth in the three study sectors, namely, the middle, north, and south areas in the western part of the GCMR. The forces with the highest influence were economic incentives in the middle sector, population increase in the north sector, and the administrative function in the south sector. Due to the lower availability of buildable land in the middle sector, the land demand and supply force had a lesser influence in this sector compared to in the north and south sectors. The development plans force had medium influence in all sectors. The geographical characteristics force had little influence in both the middle and the north sectors, but higher influence than economic incentives, availability of life facilities, and development plans in the south sector. Because of the spatial variances in life facilities organizations in the GCMR, the life facilities availability force had little effect on IU in the south sector.

  13. Ionization induced by strong electromagnetic field in low dimensional systems bound by short range forces

    Energy Technology Data Exchange (ETDEWEB)

    Eminov, P.A., E-mail: peminov@mail.ru [Moscow State University of Instrument Engineering and Computer Sciences, 20 Stromynka Street, Moscow 2107996 (Russian Federation); National Research University Higher School of Economics, 3/12 Bolshoy Trekhsvyatskiy pereulok, Moscow 109028 (Russian Federation)

    2013-10-01

    Ionization processes for a two dimensional quantum dot subjected to combined electrostatic and alternating electric fields of the same direction are studied using quantum mechanical methods. We derive analytical equations for the ionization probability in dependence on characteristic parameters of the system for both extreme cases of a constant electric field and of a linearly polarized electromagnetic wave. The ionization probabilities for a superposition of dc and low frequency ac electric fields of the same direction are calculated. The impulse distribution of ionization probability for a system bound by short range forces is found for a superposition of constant and alternating fields. The total probability for this process per unit of time is derived within exponential accuracy. For the first time the influence of alternating electric field on electron tunneling probability induced by an electrostatic field is studied taking into account the pre-exponential term.

  14. Driving forces of main landscape change processes from past 200 years in Central Europe - differences between old democratic and post-socialist countries

    Directory of Open Access Journals (Sweden)

    Skokanová Hana

    2016-03-01

    Full Text Available The article compares and points out differences in driving forces of four main landscape change processes that shaped post-socialist countries and old democratic countries of Central Europe during the last two centuries. Studying landscape change processes and corresponding driving forces helps in understanding patterns of present landscape and can help among others in better prediction of future landscape change trends. Here, the presented results are based on review of scientific articles published in peer-reviewed journals between 2000 and 2014. Driving forces affecting these processes were grouped into four categories. Economic forces drove mainly agricultural intensification; agricultural land abandonment and urbanisation and were pronounced especially in the second half of the 20th century and at the beginning of the 21st century. Technological driving forces affected agricultural intensification especially in the 19th century and the second half of the 20th century while cultural driving forces had the biggest impact on urbanisation at the beginning of the 21st century. Political driving forces affected agricultural intensification, urbanisation as well as agricultural land abandonment and were pronounced mainly during the second half of the 20th century in the post-socialist countries. Political forces in the form of subsidies drove agricultural extensification at the beginning of the 21st century. The drivers for the agricultural intensification as well as urbanisation seem to be similar for both old democratic and post-socialist countries. In contrast, agricultural land abandonment in the old democratic countries was driven by technological, cultural and economic driving forces while in the post-socialist countries the political driving forces were mainly responsible. Changes in systems for subsidies and changes in the agricultural commodity markets are also responsible for different frequencies and rates of extensification of

  15. Analysis and optimization of kinematic pair force in control rod drive mechanism

    International Nuclear Information System (INIS)

    Sun Zhenguo; Liu Sen; Ran Xiaobing; Dai Changnian; Li Yuezhong

    2015-01-01

    Function expressions of kinematic pair force with latch dimensions, friction coefficient, link angle and external load was obtained by theoretical analysis, and the expression was verified by the motion analysis software. Key parameters of kinematic pair were confirmed, and their effect trends with force of parts were obtained. They show that the available method of kinematic pair optimization is increasing the space of latch holes. Using the motion analysis software, the forces of parts before and after optimization was compared. The result shows that the forces of parts were improved after the optimization. (authors)

  16. Domains of Pyrococcus furiosus L-asparaginase fold sequentially and assemble through strong intersubunit associative forces.

    Science.gov (United States)

    Garg, Dushyant K; Tomar, Rachana; Dhoke, Reema R; Srivastava, Ankit; Kundu, Bishwajit

    2015-05-01

    Here, we report the folding and assembly of a Pyrococcus furiosus-derived protein, L-asparaginase (PfA). PfA functions as a homodimer, with each monomer made of distinct N- and C-terminal domains. The purified individual domains as well as single Trp mutant of each domain were subjected to chemical denaturation/renaturation and probed by combination of spectroscopic, chromatographic, quenching and scattering techniques. We found that the N-domain acts like a folding scaffold and assists the folding of remaining polypeptide. The domains displayed sequential folding with the N-domain having higher thermodynamic stability. We report that the extreme thermal stability of PfA is due to the presence of high intersubunit associative forces supported by extensive H-bonding and ionic interactions network. Our results proved that folding cooperativity in a thermophilic, multisubunit protein is dictated by concomitant folding and association of constituent domains directly into a native quaternary structure. This report gives an account of the factors responsible for folding and stability of a therapeutically and industrially important protein.

  17. Understanding the driving forces behind the losses of soil carbon across England and Wales

    Science.gov (United States)

    Bellamy, Patricia

    2010-05-01

    More than twice as much carbon is held in soils as in vegetation or the atmosphere, and changes in soil carbon content can have a large effect on the global carbon budget. The possibility that climate change is being reinforced by increased carbon dioxide emissions from soils owing to rising temperature is the subject of a continuing debate. But evidence for the suggested feedback mechanism has to date come solely from small-scale laboratory and field experiments and modelling studies. Here we use data from the National Soil Inventory of England and Wales obtained between 1978 and 2003 to show that carbon was lost from soils across England and Wales over the survey period at a mean rate of 0.6% yr-1 (relative to the existing soil carbon content). We find that the relative rate of carbon loss increased with soil carbon content and was more than 2% yr-1 in soils with carbon contents greater than 100 g kg-1. The relationship between rate of carbon loss and carbon content is irrespective of land use, suggesting a link to climate change. Our findings indicate that losses of soil carbon in England and Wales—and by inference in other temperate regions—are likely to have been offsetting absorption of carbon by terrestrial sinks. To investigate the possible driving forces of the measured losses of soil carbon we applied a simple model of soil carbon turnover to evaluate alternative explanations for the observed trends. We find that neither changes in decomposition resulting from the effects of climate change on soil temperature and moisture, nor changes in carbon input from vegetation, could account on their own for the overall trends. Of other explanations, results indicate that past changes in land use and management were probably dominant. The climate change signal, such as it is, is masked by these other changes. A more sophisticated model of carbon change (DAYCENT) has now been applied across the whole range of soils in England and Wales. This model has been

  18. Control of dynamical self-assembly of strongly Brownian nanoparticles through convective forces induced by ultrafast laser

    Science.gov (United States)

    Ilday, Serim; Akguc, Gursoy B.; Tokel, Onur; Makey, Ghaith; Yavuz, Ozgun; Yavuz, Koray; Pavlov, Ihor; Ilday, F. Omer; Gulseren, Oguz

    We report a new dynamical self-assembly mechanism, where judicious use of convective and strong Brownian forces enables effective patterning of colloidal nanoparticles that are almost two orders of magnitude smaller than the laser beam. Optical trapping or tweezing effects are not involved, but the laser is used to create steep thermal gradients through multi-photon absorption, and thereby guide the colloids through convective forces. Convective forces can be thought as a positive feedback mechanism that helps to form and reinforce pattern, while Brownian motion act as a competing negative feedback mechanism to limit the growth of the pattern, as well as to increase the possibilities of bifurcation into different patterns, analogous to the competition observed in reaction-diffusion systems. By steering stochastic processes through these forces, we are able to gain control over the emergent pattern such as to form-deform-reform of a pattern, to change its shape and transport it spatially within seconds. This enables us to dynamically initiate and control large patterns comprised of hundreds of colloids. Further, by not relying on any specific chemical, optical or magnetic interaction, this new method is, in principle, completely independent of the material type being assembled.

  19. Disruptive Innovations as a Driving Force for the Change of Wireless Telecommunication Infrastructures

    DEFF Research Database (Denmark)

    Kyoseva, Tsvetoslava; Poulkov, Vladimir; Mihaylov, Mihail Rumenov

    2014-01-01

    the current trends in mobile communications, we reason that the emergence of new telecommunication architectures and infrastructures is inevitable. An important consideration in the analysis is the driving role of disruptive technologies for the future of telecommunications. Based on a model for evaluating...

  20. FDR (drive-dynamics-control) - a new driving safety system with active control of brake and drive forces in the dynamic fringe range; FDR, ein neues Fahrsicherheitssystem mit aktiver Regelung der Brems- und Antriebskraefte im fahrdynamischen Grenzbereich

    Energy Technology Data Exchange (ETDEWEB)

    Erhardt, R. [Bosch (R.) GmbH, Stuttgart (Germany); Zanten, A.T. van [Bosch (R.) GmbH, Stuttgart (Germany)

    1995-12-31

    BOSCH is going to introduce a new driving safety system in 1995, the FDR (drive-dynamics-control). Using the measured and estimated dynamic magnitudes as a basis, the system calculates inhowfar the actual vehicle motion differs from the desired stable trace- and direction-consistent handling properties. Depending on the driving situation and driver`s wishes the braking and driving forces at the wheels are adjusted with a considerable divergence in order to achieve the desired handling properties. The system improves the driving stability in all operating states as soon as the dynamic limiting range is reached. It even reduces the risk of skidding in case of extreme steering manoeuvres and also enables the safe control of the vehicle in critical traffic situations. Furthermore the system offers improved basic anti-skid braking system and anti-slip control functions. Due to these advantages it can be expected that the FDR is going to make an important contribution to avoiding accidents and reducing damage. (orig.) [Deutsch] Mit FDR (Fahr-Dynamik-Regelung) wird BOSCH 1995 ein neues Fahrsicherheitssystem einfuehren. Das System berechnet auf der Basis gemessener und geschaetzter fahrdynamischer Groessen, wie stark die tatsaechliche Fahrzeugbewegung von einem gewuenschten stabilen, spur- und richtungstreuen Fahrverhalten abweicht. Die Brems- und Antriebskraefte an den Raedern werden bei deutlicher Abweichung abhaengig von Fahrsituation und Fahrerwunsch so eingestellt, dass die Abweichung minimiert und das gewuenschte Fahrverhalten weitgehend erreicht wird. Das System verbessert die Fahrstabilitaet in allen Betriebszustaenden, sobald der fahrdynamische Grenzbereich erreicht wird. Es reduziert selbst bei extremen Lenkmanoevern die Schleudergefahr drastisch und ermoeglicht auch in kritischen Verkehrssituationen die sicherere Beherrschung des Fahrzeugs. Darueberhinaus bietet das System verbesserte ABS- und ASR-Grundfunktionen. Diese Vorteile lassen erwarten, dass FDR einen

  1. Mechanical characterization and force-displacement hysteretic curves from in-plane cyclic tests on strong masonry infills.

    Science.gov (United States)

    Morandi, Paolo; Hak, Sanja; Magenes, Guido

    2018-02-01

    This article contains information related to a recent study "Performance-based interpretation of in-plane cyclic tests on RC frames with strong masonry infills" (Morandi et al., 2017 [1]). Motivated by the necessity to improve the knowledge of the in-plane seismic response of rigid strong masonry infills, a wide experimental campaign based on in-plane cyclic tests on full-scale RC infilled frame specimens, supplemented with a complete characterization of the materials, has been conducted at the laboratory of the Department of Civil Engineering and Architecture of the University of Pavia. The masonry is constituted by vertically perforated 35 cm thick clay units with tongue and groove and dry head-joints and general-purpose mortar bed-joints. The paper reports the results of the mechanical characterization and of the force-displacement hysteretic curves from the in-plane cyclic tests.

  2. Mechanical characterization and force-displacement hysteretic curves from in-plane cyclic tests on strong masonry infills

    Directory of Open Access Journals (Sweden)

    Paolo Morandi

    2018-02-01

    Full Text Available This article contains information related to a recent study “Performance-based interpretation of in-plane cyclic tests on RC frames with strong masonry infills” (Morandi et al., 2017 [1]. Motivated by the necessity to improve the knowledge of the in-plane seismic response of rigid strong masonry infills, a wide experimental campaign based on in-plane cyclic tests on full-scale RC infilled frame specimens, supplemented with a complete characterization of the materials, has been conducted at the laboratory of the Department of Civil Engineering and Architecture of the University of Pavia. The masonry is constituted by vertically perforated 35 cm thick clay units with tongue and groove and dry head-joints and general-purpose mortar bed-joints. The paper reports the results of the mechanical characterization and of the force-displacement hysteretic curves from the in-plane cyclic tests.

  3. Strong-field ionization of xenon dimers: The effect of two-equivalent-center interference and of driving ionic transitions

    Science.gov (United States)

    Zhang, C.; Feng, T.; Raabe, N.; Rottke, H.

    2018-02-01

    Strong-field ionization (SFI) of the homonuclear noble gas dimer Xe2 is investigated and compared with SFI of the Xe atom and of the ArXe heteronuclear dimer by using ultrashort Ti:sapphire laser pulses and photoelectron momentum spectroscopy. The large separation of the two nuclei of the dimer allows the study of two-equivalent-center interference effects on the photoelectron momentum distribution. Comparing the experimental results with a new model calculation, which is based on the strong-field approximation, actually reveals the influence of interference. Moreover, the comparison indicates that the presence of closely spaced gerade and ungerade electronic state pairs of the Xe2 + ion at the Xe2 ionization threshold, which are strongly dipole coupled, affects the photoelectron momentum distribution.

  4. Counterevidence to the ion hammering scenario as a driving force for the shape elongation of embedded nanoparticles

    Science.gov (United States)

    Amekura, H.; Okubo, N.; Tsuya, D.; Ishikawa, N.

    2017-08-01

    Counterevidence is provided in the ion-hammering scenario as a driving force for the shape elongation of embedded nanoparticles (NPs) under swift heavy ion irradiation (SHII). Ion-induced compaction and the hammering, which are both induced in silica under SHII, dominate at low and high fluences, respectively, causing a crossover between them around a fluence of ˜4 × 1012 ions/cm2. Nevertheless, the shape elongation of NPs detected by the optical dichroism exhibits nearly linear dependence in a wide fluence range between ˜1 × 1011 and 2 × 1013 ions/cm2, indicating that the hammering does not play an important role.

  5. Driving forces of Indian summer monsoon on Milankovitch and sub-Milankovitch time scales: A review

    Digital Repository Service at National Institute of Oceanography (India)

    Naidu, P.D.

    A scientific consensus exists that tectonic evolution of Himalaya is the main cause of monsoon initiation and evolution in southeast Asia. Several forcing factors such as tectonic, solar insolation, latent heat transport, albedo of the earth surface...

  6. Measuring Risky Driving Behavior Using an mHealth Smartphone App: Development and Evaluation of gForce.

    Science.gov (United States)

    Freidlin, Raisa Z; Dave, Amisha D; Espey, Benjamin G; Stanley, Sean T; Garmendia, Marcial A; Pursley, Randall; Ehsani, Johnathon P; Simons-Morton, Bruce G; Pohida, Thomas J

    2018-04-19

    Naturalistic driving studies, designed to objectively assess driving behavior and outcomes, are conducted by equipping vehicles with dedicated instrumentation (eg, accelerometers, gyroscopes, Global Positioning System, and cameras) that provide continuous recording of acceleration, location, videos, and still images for eventual retrieval and analyses. However, this research is limited by several factors: the cost of equipment installation; management and storage of the large amounts of data collected; and data reduction, coding, and analyses. Modern smartphone technology includes accelerometers built into phones, and the vast, global proliferation of smartphones could provide a possible low-cost alternative for assessing kinematic risky driving. We evaluated an in-house developed iPhone app (gForce) for detecting elevated g-force events by comparing the iPhone linear acceleration measurements with corresponding acceleration measurements obtained with both a custom Android app and the in-vehicle miniDAS data acquisition system (DAS; Virginia Tech Transportation Institute). The iPhone and Android devices were dashboard-mounted in a vehicle equipped with the DAS instrumentation. The experimental protocol consisted of driving maneuvers on a test track, such as cornering, braking, and turning that were performed at different acceleration levels (ie, mild, moderate, or hard). The iPhone gForce app recorded linear acceleration (ie, gravity-corrected). The Android app recorded gravity-corrected and uncorrected acceleration measurements, and the DAS device recorded gravity-uncorrected acceleration measurements. Lateral and longitudinal acceleration measures were compared. The correlation coefficients between the iPhone and DAS acceleration measurements were slightly lower compared to the correlation coefficients between the Android and DAS, possibly due to the gravity correction on the iPhone. Averaging the correlation coefficients for all maneuvers, the longitudinal and

  7. Bilateral deficit in explosive force production is not caused by changes in agonist neural drive.

    Directory of Open Access Journals (Sweden)

    Matthew W Buckthorpe

    Full Text Available Bilateral deficit (BLD describes the phenomenon of a reduction in performance during synchronous bilateral (BL movements when compared to the sum of identical unilateral (UL movements. Despite a large body of research investigating BLD of maximal voluntary force (MVF there exist a paucity of research examining the BLD for explosive strength. Therefore, this study investigated the BLD in voluntary and electrically-evoked explosive isometric contractions of the knee extensors and assessed agonist and antagonist neuromuscular activation and measurement artefacts as potential mechanisms. Thirteen healthy untrained males performed a series of maximum and explosive voluntary contractions bilaterally (BL and unilaterally (UL. UL and BL evoked twitch and octet contractions were also elicited. Two separate load cells were used to measure MVF and explosive force at 50, 100 and 150 ms after force onset. Surface EMG amplitude was measured from three superficial agonists and an antagonist. Rate of force development (RFD and EMG were reported over consecutive 50 ms periods (0-50, 50-100 and 100-150 ms. Performance during UL contractions was compared to combined BL performance to measure BLD. Single limb performance during the BL contractions was assessed and potential measurement artefacts, including synchronisation of force onset from the two limbs, controlled for. MVF showed no BLD (P = 0.551, but there was a BLD for explosive force at 100 ms (11.2%, P = 0.007. There was a BLD in RFD 50-100 ms (14.9%, P = 0.004, but not for the other periods. Interestingly, there was a BLD in evoked force measures (6.3-9.0%, P<0.001. There was no difference in agonist or antagonist EMG for any condition (P≥0.233. Measurement artefacts contributed minimally to the observed BLD. The BLD in volitional explosive force found here could not be explained by measurement issues, or agonist and antagonist neuromuscular activation. The BLD in voluntary and evoked explosive force

  8. Polyphilic Interactions as Structural Driving Force Investigated by Molecular Dynamics Simulation (Project 7

    Directory of Open Access Journals (Sweden)

    Christopher Peschel

    2017-09-01

    Full Text Available We investigated the effect of fluorinated molecules on dipalmitoylphosphatidylcholine (DPPC bilayers by force-field molecular dynamics simulations. In the first step, we developed all-atom force-field parameters for additive molecules in membranes to enable an accurate description of those systems. On the basis of this force field, we performed extensive simulations of various bilayer systems containing different additives. The additive molecules were chosen to be of different size and shape, and they included small molecules such as perfluorinated alcohols, but also more complex molecules. From these simulations, we investigated the structural and dynamic effects of the additives on the membrane properties, as well as the behavior of the additive molecules themselves. Our results are in good agreement with other theoretical and experimental studies, and they contribute to a microscopic understanding of interactions, which might be used to specifically tune membrane properties by additives in the future.

  9. Identifying the driving forces of urban expansion and its environmental impact in Jakarta-Bandung mega urban region

    Science.gov (United States)

    Pravitasari, A. E.; Rustiadi, E.; Mulya, S. P.; Setiawan, Y.; Fuadina, L. N.; Murtadho, A.

    2018-05-01

    The socio-economic development in Jakarta-Bandung Mega Urban Region (JBMUR) caused the increasing of urban expansion and led to a variety of environmental damage such as uncontrolled land use conversion and raising anthropogenic disaster. The objectives of this study are: (1) to identify the driving forces of urban expansion that occurs on JBMUR and (2) to analyze the environmental quality decline on JBMUR by producing time series spatial distribution map and spatial autocorrelation of floods and landslide as the proxy of anthropogenic disaster. The driving forces of urban expansion in this study were identified by employing Geographically Weighted Regression (GWR) model using 6 (six) independent variables, namely: population density, percentage of agricultural land, distance to the center of capital city/municipality, percentage of household who works in agricultural sector, distance to the provincial road, and distance to the local road. The GWR results showed that local demographic, social and economic factors including distance to the road spatially affect urban expansion in JBMUR. The time series spatial distribution map of floods and landslide event showed the spatial cluster of anthropogenic disaster in some areas. Through Local Moran Index, we found that environmental damage in one location has a significant impact on the condition of its surrounding area.

  10. Land use changes and its driving forces in hilly ecological restoration area based on gis and rs of northern china

    Science.gov (United States)

    Gao, Peng; Niu, Xiang; Wang, Bing; Zheng, Yunlong

    2015-01-01

    Land use change is one of the important aspects of the regional ecological restoration research. With remote sensing (RS) image in 2003, 2007 and 2012, using geographic information system (GIS) technologies, the land use pattern changes in Yimeng Mountain ecological restoration area in China and its driving force factors were studied. Results showed that: (1) Cultivated land constituted the largest area during 10 years, and followed by forest land and grass land; cultivated land and unused land were reduced by 28.43% and 44.32%, whereas forest land, water area and land for water facilities and others were increased. (2) During 2003–2007, forest land change showed the largest, followed by unused land and grass land; however, during 2008–2012, water area and land for water facilities change showed the largest, followed by grass land and unused land. (3) Land use degree was above the average level, it was in the developing period during 2003–2007 and in the degenerating period during 2008–2012. (4) Ecological Restoration Projects can greatly change the micro topography, increase vegetation coverage, and then induce significant changes in the land use distribution, which were the main driving force factors of the land use pattern change in the ecological restoration area. PMID:26047160

  11. Exciplexes versus Loose Ion Pairs: How Does the Driving Force Impact the Initial Product Ratio of Photoinduced Charge Separation Reactions?

    Science.gov (United States)

    2014-01-01

    Many donor–acceptor systems can undergo a photoinduced charge separation reaction, yielding loose ion pairs (LIPs). LIPs can be formed either directly via (distant) electron transfer (ET) or indirectly via the dissociation of an initially formed exciplex or tight ion pair. Establishing the prevalence of one of the reaction pathways is challenging because differentiating initially formed exciplexes from LIPs is difficult due to similar spectroscopic footprints. Hence, no comprehensive reaction model has been established for moderately polar solvents. Here, we employ an approach based on the time-resolved magnetic field effect (MFE) of the delayed exciplex luminescence to distinguish the two reaction channels. We focus on the effects of the driving force of ET and the solvent permittivity. We show that, surprisingly, the exciplex channel is significant even for an exergonic ET system with a free energy of ET of −0.58 eV and for the most polar solutions studied (butyronitrile). Our findings demonstrate that exciplexes play a crucial role even in polar solvents and at moderate driving forces, contrary to what is usually assumed. PMID:25243054

  12. Relative importance of driving force and electrostatic interactions in the reduction of multihaem cytochromes by small molecules.

    Science.gov (United States)

    Quintas, Pedro O; Cepeda, Andreia P; Borges, Nuno; Catarino, Teresa; Turner, David L

    2013-06-01

    Multihaem cytochromes are essential to the energetics of organisms capable of bioremediation and energy production. The haems in several of these cytochromes have been discriminated thermodynamically and their individual rates of reduction by small electron donors were characterized. The kinetic characterization of individual haems used the Marcus theory of electron transfer and assumed that the rates of reduction of each haem by sodium dithionite depend only on the driving force, while electrostatic interactions were neglected. To determine the relative importance of these factors in controlling the rates, we studied the effect of ionic strength on the redox potential and the rate of reduction by dithionite of native Methylophilus methylotrophus cytochrome c″ and three mutants at different pH values. We found that the main factor determining the rate is the driving force and that Marcus theory describes this satisfactorily. This validates the method of the simultaneous fitting of kinetic and thermodynamic data in multihaem cytochromes and opens the way for further investigation into the mechanisms of these proteins. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Inhibiting and driving forces for the digitalization of security systems: security officers’ view on the issue

    OpenAIRE

    Lahtinen, Markus

    2007-01-01

    This memo reports on factors that drive and inhibit the digitalization of security systems. The reported factors are as follows: Technology-push factors • Need to lower costs on the end-user side, i.e. replacing labour with technology • Perceived convenience and ease-of-use of digital systems • Digital products can be connected to the current enterprise network; enabling an expanding set of security features • Firms holding the IP-capability (IP=Internet Protocol) and not h...

  14. External and internal influences as driving forces and/or stumbling ...

    African Journals Online (AJOL)

    The development of national and institutional quality assurance and management systems is often forced (rightfully or wrongly) into a specific direction by external and internal environmental influences. In South Africa such influences play a major role in both the national higher education policy developments and the ...

  15. Numerical prediction of local transitional features of turbulent forced gas flows in circular tubes with strong heating

    International Nuclear Information System (INIS)

    Ezato, Koichiro; Kunugi, Tomoaki; Shehata, A.M.; McEligot, D.M.

    1997-03-01

    Previous numerical simulation for the laminarization due to heating of the turbulent flow in pipe were assessed by comparison with only macroscopic characteristics such as heat transfer coefficient and pressure drop, since no experimental data on the local distributions of the velocity and temperature in such flow situation was available. Recently, Shehata and McEligot reported the first measurements of local distributions of velocity and temperature for turbulent forced air flow in a vertical circular tube with strongly heating. They carried out the experiments in three situations from turbulent flow to laminarizing flow according to the heating rate. In the present study, we analyzed numerically the local transitional features of turbulent flow evolving laminarizing due to strong heating in their experiments by using the advanced low-Re two-equation turbulence model. As the result, we successfully predicted the local distributions of velocity and temperature as well as macroscopic characteristics in three turbulent flow conditions. By the present study, a numerical procedure has been established to predict the local characteristics such as velocity distribution of the turbulent flow with large thermal-property variation and laminarizing flow due to strong heating with enough accuracy. (author). 60 refs

  16. Evaluation on driving force of natural circulation in downcomer for passive residual heat removal system in JAERI passive safety reactor JPSR

    International Nuclear Information System (INIS)

    Kunii, Katsuhiko; Iwamura, Takamichi; Murao, Yoshio

    1997-01-01

    The driving-force of the natural circulation in the residual heat removal (RHR) system for the JPSR (JAERI Passive Safety Reactor) is given as a gravity force of the density difference between hotter coolant in core and upper plenum and cooler coolant in downcomer. The amount of density difference and time to achieve the enough density difference for the RHR system change directly dependent on the thermal fluid flow pattern in downcomer of annulus flow pass. The purposes of the present study are to investigate the possibilities of the followings by evaluating the three-dimensional thermal fluid flow in downcomer by numerical analysis using the STREAM code; 1) promotion of making the flow pattern uniform in downcomer by installing a baffle, 2) achievement of an enough driving-force of the natural circulation, 3) validity of one-point assumption, that is, complete mixing down-flow assumption for the three-dimensional thermal fluid flow in downcomer to evaluate the function of the passive RHR system. The following conclusions were obtained: (1) The effect of baffle on the thermal fluid flow and driving-force is little, (2) The driving-force required for natural circulation cooling can be obtained in wide range of inlet velocity even if the flow is multi-dimensional, (3) Both in initial transient stage and in steady-state, the one-point assumption can be applied to evaluate the driving-force of natural circulation in the passive RHR system. (author)

  17. Dynamics of aeolian desertification and its driving forces in the Horqin Sandy Land, Northern China.

    Science.gov (United States)

    Duan, Han-chen; Wang, Tao; Xue, Xian; Liu, Shu-lin; Guo, Jian

    2014-10-01

    Aeolian desertification is one of the most serious environmental and socioeconomic problems in arid, semi-arid, and dry subhumid zones. Understanding desertification processes and causes is important to provide reasonable and effective control measures for preventing desertification. With satellite remote sensing images as data source to assess the temporal and spatial dynamics of desertification from 1975 to 2010 in the Horqin Sandy Land, dynamic changes of aeolian desertification were detected using the human-machine interactive interpretation method. The driving factors of local desertification were analyzed based on natural and socioeconomic data. The results show that aeolian desertified land in the study area covered 30,199 km(2) in 2010, accounting for 24.1% of the study area. The total area of aeolian desertified land obviously expanded from 30,884 km(2) in 1975 to 32,071 km(2) in 1990, and gradually decreased to 30,199 km(2) in 2010; aeolian desertified land represented an increasing trend firstly and then decreased. During the past 35 years, the gravity centers of desertified lands that are classified as extremely severe and severe generally migrated to the northeast, whereas those that are moderate and slight migrated to the northwest. The migration distance of severely desertified land was the largest, which indicated the southern desertified lands were improved during the last few decades. In addition, the climatic variation in the past 35 years has been favorable to desertification in the Horqin Sandy Land. Aeolian desertified land rapidly expanded from 1975 to 1990 under the combined effects of climate changes and unreasonable human activities. After the 1990s, the main driving factors responsible for the decrease in desertification were positive human activities, such as the series of antidesertification and ecological restoration projects.

  18. Spatial Patterns and Driving Forces of Greenhouse Land Change in Shouguang City, China

    Directory of Open Access Journals (Sweden)

    Bohua Yu

    2017-03-01

    Full Text Available As an important facet of modern agricultural development, greenhouses satisfy ever-increasing demands for agricultural production and, therefore, constitute a growing proportion of global agriculture. However, just a handful of countries regularly collect statistics on the land cover of greenhouse infrastructure. Even when collected, these data cannot provide the detailed spatial information required for environmental risk assessment. It is, therefore, important to map spatial changes in greenhouse land cover using remote sensing (RS approaches to determine the underlying factors driving these changes. In this paper, we apply a support vector machine (SVM algorithm to identify greenhouse land cover in Shouguang City, China. Enhanced thematic mapper (ETM images were selected as the data source for land use classification in this study as they can be freely acquired and offer the necessary spatial resolution. We then used a binary logistic regression model to quantitatively discern the mechanisms underlying changes in greenhouse land cover. The results of this study show that greenhouse land cover in Shouguang increased by 50.51% between 2000 and 2015, and that 90.39% of this expansion took place between 2010 and 2015. Elevation, slope, precipitation, and the distance to the nearest rural settlements and coastline are all significant factors driving expansion in greenhouse land cover, while distance to the nearest urban areas, rivers, roads, railways, and coastline have contributed to contractions in this land use type. Our research provided a practical approach to allow the detection of changes in greenhouse land cover in the countries with using free or low-cost satellite images.

  19. Driving forces of rapid CO2 emissions growth: A case of Korea

    International Nuclear Information System (INIS)

    Kim, Yong-Gun; Yoo, Jonghyun; Oh, Wankeun

    2015-01-01

    This study aims to investigate Korea's final demand structure and its impacts on CO 2 emissions in order to reduce CO 2 emissions and develop environmental policy directions. Based on the environmentally extended input–output model, this study adopts a two-step approach: (1) to estimate the embodied emissions and their intensities for 393 sectors induced by final demand; and (2) to calculate the driving factors of emission growth between 2003 and 2011 and then evaluate the result by using Structural Decomposition Analysis (SDA). The findings of this study demonstrate that the impact of composition change in export with less embodied emission intensities tends to offset the increase in CO 2 emission by the export scale growth. The relatively low residential electricity price has resulted in the rapid growth of household electricity consumption and significantly contributed to emissions growth. The result of SDA indicates that Korea's final demand behavior yielded high carbonization over the same period. The findings suggest that Korean government should promote exports in industries with less embedded CO 2 in order to protect environments. In addition, emission information of each product and service should be provided for consumers to change their purchase patterns towards contributing to low carbon emissions as active players. -- Highlights: •We investigate Korea's final demand structure and its contribution to CO 2 emissions. •Using SDA, we evaluate the driving factors of emission growth from 2003 to 2011. •Exports play a critical role in Korea's CO 2 emissions growth. •The relatively low residential electricity price has contributed to emission growth. •Korea's final demand behavior yielded high carbonization over the same period

  20. Prerequisites and driving forces behind an extended working life among older workers.

    Science.gov (United States)

    Hovbrandt, Pia; Håkansson, Carita; Albin, Maria; Carlsson, Gunilla; Nilsson, Kerstin

    2017-11-28

    Reforms are changing pension systems in many European countries, in order to both restrict early retirement and force people to extend their working life. From occupational therapy and occupational science perspectives, studies focusing on aspects of working life that motivate the older worker is urgent. The aim was to describe incentives behind an extended working life among people over age 65. Focus group methodology was used, with participants ages 66-71, from varying work fields: construction and technical companies and the municipal elderly care sector. Work was considered important and valuable to the degree of how challenging work was, the possibilities for inclusion in a team of colleagues and the chances for better personal finances. Amongst all, the participants expressed a feeling of a strengthened identity by being challenged and having the opportunity to manage working tasks. The finding showed the actual reasons behind an extended working life among older workers. However, a risk of rising social inequity may appear with increased working life if older people are forced to extend their working life due to a difficult financial situation as a pensioner. A variety of retirement options and initiatives in order to support older workers are justified.

  1. Geological and climatic forces driving speciation in the continentally distributed trilling chorus frogs (Pseudacris).

    Science.gov (United States)

    Lemmon, Emily Moriarty; Lemmon, Alan R; Cannatella, David C

    2007-09-01

    Tertiary geological events and Quaternary climatic fluctuations have been proposed as important factors of speciation in the North American flora and fauna. Few studies, however, have rigorously tested hypotheses regarding the specific factors driving divergence of taxa. Here, we test explicit speciation hypotheses by correlating geologic events with divergence times among species in the continentally distributed trilling chorus frogs (Pseudacris). In particular, we ask whether marine inundation of the Mississippi Embayment, uplift of the Appalachian Mountains, or modification of the ancient Teays-Mahomet River system contributed to speciation. To examine the plausibility of ancient rivers causing divergence, we tested whether modern river systems inhibit gene flow. Additionally, we compared the effects of Quaternary climatic factors (glaciation and aridification) on levels of genetic variation. Divergence time estimates using penalized likelihood and coalescent approaches indicate that the major lineages of chorus frogs diversified during the Tertiary, and also exclude Quaternary climate change as a factor in speciation of chorus frogs. We show the first evidence that inundation of the Mississippi Embayment contributed to speciation. We reject the hypotheses that Cenozoic uplift of the Appalachians and that diversion of the Teays-Mahomet River contributed to speciation in this clade. We find that by reducing gene flow, rivers have the potential to cause divergence of lineages. Finally, we demonstrate that populations in areas affected by Quaternary glaciation and aridification have reduced levels of genetic variation compared to those from more equable regions, suggesting recent colonization.

  2. Research Problems Associated with Limiting the Applied Force in Vibration Tests and Conducting Base-Drive Modal Vibration Tests

    Science.gov (United States)

    Scharton, Terry D.

    1995-01-01

    The intent of this paper is to make a case for developing and conducting vibration tests which are both realistic and practical (a question of tailoring versus standards). Tests are essential for finding things overlooked in the analyses. The best test is often the most realistic test which can be conducted within the cost and budget constraints. Some standards are essential, but the author believes more in the individual's ingenuity to solve a specific problem than in the application of standards which reduce problems (and technology) to their lowest common denominator. Force limited vibration tests and base-drive modal tests are two examples of realistic, but practical testing approaches. Since both of these approaches are relatively new, a number of interesting research problems exist, and these are emphasized herein.

  3. Strongly-sheared wind-forced currents in the nearshore regions of the central Southern California Bight

    Science.gov (United States)

    Noble, Marlene A.; Rosenberger, Kurt; Robertson, George L.

    2015-01-01

    Contrary to many previous reports, winds do drive currents along the shelf in the central portion of the Southern California Bight (SCB). Winds off Huntington Beach CA are the dominant forcing for currents over the nearshore region of the shelf (water depths less than 20 m). Winds control about 50–70% of the energy in nearshore alongshelf surface currents. The wind-driven current amplitudes are also anomalously high. For a relatively weak 1 dyne/cm2 wind stress, the alongshelf surface current amplitudes in this region can reach 80 cm/s or more. Mid-depth current amplitudes for the same wind stress are around 30–40 cm/s. These wind-driven surface current amplitudes are much larger than previously measured over other nearshore shelf regions, perhaps because this program is one of the few that measured currents within a meter of the surface. The near-bed cross-shelf currents over the nearshore region of the Huntington Beach shelf have an Ekman response to winds in that they upwell (downwell) for down (up) coast winds. This response disappears further offshore. Hence, there is upwelling in the SCB, but it does not occur across the entire shelf. Subthermocline water in the nearshore region that may contain nutrients and plankton move onshore when winds are southeastward, but subthermocline water over the shelf break is not transported to the beach. The currents over the outer shelf are not predominately controlled by winds, consistent with previous reports. Instead, they are mainly driven by cross-shelf pressure gradients that are independent of local wind stress.

  4. Analyzing driving forces behind changes in energy vulnerability of Spanish electricity generation through a Divisia index-based method

    International Nuclear Information System (INIS)

    Fernández González, P.; Moreno, B.

    2015-01-01

    Highlights: • We propose and develop the LMDI approach to factorize changes in electricity bill vulnerability. • Spanish vulnerability (1995–2011) markedly grew mainly by increasing gas dependence. • Fuel price increase and growing importance of electricity damage energy security. • Energy intensity advances & fuel diversification: insufficient to drive vulnerability. • Main recommendation: enhance internal energy market and common external EU strategy. - Abstract: High energy dependence on fossil raises vulnerability concerns about security of supply and energy cost. This research examines the impact of high dependence of imported fuels for power generation in Spain through the quantification and analysis of the driving forces behind the change in its electricity bill. Following logarithmic mean Divisia indexes approach, we present and perform a new method that enables a complete decomposition of changes in electricity vulnerability into contributions from several drivers. In fact, we identify five predefined factors behind the variations in vulnerability in Spain during the 1998–2011 period: fuel price, average heat rate, fuel dependence, degree of electricity importance and energy intensity. The application of this approach reveals a significant increase in Spanish vulnerability in the last two decades, promoted by increments in fuel price and importance of electricity over the primary energy consumption, but especially by increasing fuel dependence (particularly gas dependence). Therefore, findings mainly advocate for those strategies aimed at reducing Spanish energy dependence. Also those improving thermal efficiency and energy intensity are indicated

  5. Mining spatial information to investigate the evolution of karst rocky desertification and its human driving forces in Changshun, China.

    Science.gov (United States)

    Xu, Erqi; Zhang, Hongqi; Li, Mengxian

    2013-08-01

    The processes of karst rocky desertification (KRD) have been found to cause the most severe environmental degradation in southwestern China. Understanding the driving forces that cause KRD is essential for managing and restoring the areas that it impacts. Studies of the human driving forces of KRD are limited to the county level, a specific administrative unit in China; census data are acquired at this scale, which can lead to scale biases. Changshun County is studied here as a representative area and anthropogenic influences in the county are accounted for by using Euclidean distances for the proximity to roads and settlements. We propose a standard coefficient of human influence (SOI) that standardizes the Euclidean distances for different KRD transformations to compare the effects of human activities in different areas. In Changshun County, the individual influences of roads and settlements share similar characteristics. The SOIs of improved KRD transformation types are almost negative, but the SOIs of deteriorated types are nearly positive except for one form of KRD turning to the extremely severe KRD. The results indicated that the distribution and evolution of the KRD areas from 2000 to 2010 in Changshun were affected positively by human activities (e.g., KRD restoration projects) and also negatively (e.g., by intense and irrational land use). Our results demonstrate that the spatial techniques and SOI used in this study can effectively incorporate information concerning human influences and internal KRD transformations. This provides a suitable approach for studying the relationships between human activities and KRD processes at fine scales. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Tendency to occupy a statistically dominant spatial state of the flow as a driving force for turbulent transition.

    Science.gov (United States)

    Chekmarev, Sergei F

    2013-03-01

    The transition from laminar to turbulent fluid motion occurring at large Reynolds numbers is generally associated with the instability of the laminar flow. On the other hand, since the turbulent flow characteristically appears in the form of spatially localized structures (e.g., eddies) filling the flow field, a tendency to occupy such a structured state of the flow cannot be ruled out as a driving force for turbulent transition. To examine this possibility, we propose a simple analytical model that treats the flow as a collection of localized spatial structures, each of which consists of elementary cells in which the behavior of the particles (atoms or molecules) is uncorrelated. This allows us to introduce the Reynolds number, associating it with the ratio between the total phase volume for the system and that for the elementary cell. Using the principle of maximum entropy to calculate the most probable size distribution of the localized structures, we show that as the Reynolds number increases, the elementary cells group into the localized structures, which successfully explains turbulent transition and some other general properties of turbulent flows. An important feature of the present model is that a bridge between the spatial-statistical description of the flow and hydrodynamic equations is established. We show that the basic assumptions underlying the model, i.e., that the particles are indistinguishable and elementary volumes of phase space exist in which the state of the particles is uncertain, are involved in the derivation of the Navier-Stokes equation. Taking into account that the model captures essential features of turbulent flows, this suggests that the driving force for the turbulent transition is basically the same as in the present model, i.e., the tendency of the system to occupy a statistically dominant state plays a key role. The instability of the flow at high Reynolds numbers can then be a mechanism to initiate structural rearrangement of

  7. The driving forces for nitrogen and phosphorus flows in the food chain of china, 1980 to 2010.

    Science.gov (United States)

    Hou, Y; Ma, L; Gao, Z L; Wang, F H; Sims, J T; Ma, W Q; Zhang, F S

    2013-07-01

    Nitrogen (N) and phosphorus (P) use and losses in China's food chain have accelerated in the past three decades, driven by population growth, rapid urbanization, dietary transition, and changing nutrient management practice. There has been little detailed quantitative analysis of the relative magnitude of these driving forces throughout this period. Therefore, we analyzed changes in N and P flows and key drivers behind changes in the food (production and consumption) chain at the national scale from 1980 to 2010. Food (N and P) consumption increased by about fivefold in urban settings over this period but has decreased in rural settings since the 1990s. For urban settings, the integrated driving forces for increased food consumption were population growth, which accounted for ∼60%, and changing urban diets toward a greater emphasis on the consumption of animal products. Nutrient inputs and losses in crop and animal productions have continuously increased from 1980 to 2010, but the rates of decadal increase were greatly different. Increased total inputs and losses in crop production were primarily driven by increased crop production for food demand (68-96%) in the 1980s but were likely offset in the 2000s by improved nutrient management practices, as evidenced by decreased total inputs to and losses from cropland for harvesting per nutrient in crop. The contributions of animal production to total N and P losses to waters from the food chain increased by 34 and 60% from 1980 to 2010. These increases were caused mainly by decreased ratios of manure returned to cropland. Our study highlights a larger impact of changing nutrient management practice than population growth on elevated nutrient flows in China's food chain. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  8. Transitions in Land Use Architecture under Multiple Human Driving Forces in a Semi-Arid Zone

    Directory of Open Access Journals (Sweden)

    Issa Ouedraogo

    2015-07-01

    Full Text Available The present study aimed to detect the main shifts in land-use architecture and assess the factors behind the changes in typical tropical semi-arid land in Burkina Faso. Three sets of time-series LANDSAT data over a 23-year period were used to detect land use changes and their underpinning drivers in multifunctional but vulnerable ecologies. Group discussions in selected villages were organized for mapping output interpretation and collection of essential drivers of change as perceived by local populations. Results revealed profound changes and transitions during the study period. During the last decade, shrub and wood savannahs exhibited high net changes (39% and −37% respectively with a weak net positive change for cropland (only 2%, while cropland and shrub savannah exhibited high swap (8% and 16%. This suggests that the area of cropland remained almost unchanged but was subject to relocation, wood savannah decreased drastically, and shrub savannah increased exponentially. Cropland exhibited a null net persistence while shrub and wood savannahs exhibited positive and negative net persistence (1.91 and −10.24, respectively, indicating that there is movement toward agricultural intensification and wood savannah tended to disappear to the benefit of shrub savannah. Local people are aware of the changes that have occurred and support the idea that illegal wood cutting and farming are inappropriate farming practices associated with immigration; absence of alternative cash generation sources, overgrazing and increasing demand for wood energy are driving the changes in their ecosystems. Policies that integrate restoration and conservation of natural ecosystems and promote sustainable agroforestry practices in the study zone are highly recommended.

  9. Controlling plasma distributions as driving forces for ion migration during fs laser writing

    International Nuclear Information System (INIS)

    Fernandez, Toney Teddy; Siegel, Jan; Hoyo, Jesus; Solis, Javier; Sotillo, Belen; Fernandez, Paloma

    2015-01-01

    The properties of structures written inside dielectrics with high repetition rate femtosecond lasers are known to depend strongly on the complex interplay of a large number of writing parameters. Recently, ion migration within the laser-excited volume has been identified as a powerful mechanism for changing the local element distribution and producing efficient optical waveguides. In this work it is shown that the transient plasma distribution induced during laser irradiation is a reliable monitor for predicting the final refractive index distribution of the waveguide caused by ion migration. By performing in situ plasma emission microscopy during the writing process inside a La-phosphate glass it is found that the long axis of the plasma distribution determines the axis of ion migration, being responsible for the local refractive index increase. This observation is also valid when strong positive or negative spherical aberration is induced, greatly deforming the focal volume and inverting the index profile. Even subtle changes in the writing conditions, such as an inversion of the writing direction (quill writing effect), show up in the form of a modified plasma distribution, which manifests as a modified index distribution. Finally, it is shown that the superior control over the waveguide properties employing the slit shaping technique is caused by the more confined plasma distribution produced. The underlying reasons for this unexpected result are discussed in terms of non-linear propagation and heat accumulation. (paper)

  10. Controlling plasma distributions as driving forces for ion migration during fs laser writing

    Science.gov (United States)

    Teddy Fernandez, Toney; Siegel, Jan; Hoyo, Jesus; Sotillo, Belen; Fernandez, Paloma; Solis, Javier

    2015-04-01

    The properties of structures written inside dielectrics with high repetition rate femtosecond lasers are known to depend strongly on the complex interplay of a large number of writing parameters. Recently, ion migration within the laser-excited volume has been identified as a powerful mechanism for changing the local element distribution and producing efficient optical waveguides. In this work it is shown that the transient plasma distribution induced during laser irradiation is a reliable monitor for predicting the final refractive index distribution of the waveguide caused by ion migration. By performing in situ plasma emission microscopy during the writing process inside a La-phosphate glass it is found that the long axis of the plasma distribution determines the axis of ion migration, being responsible for the local refractive index increase. This observation is also valid when strong positive or negative spherical aberration is induced, greatly deforming the focal volume and inverting the index profile. Even subtle changes in the writing conditions, such as an inversion of the writing direction (quill writing effect), show up in the form of a modified plasma distribution, which manifests as a modified index distribution. Finally, it is shown that the superior control over the waveguide properties employing the slit shaping technique is caused by the more confined plasma distribution produced. The underlying reasons for this unexpected result are discussed in terms of non-linear propagation and heat accumulation.

  11. Sequential actin-based pushing forces drive meiosis I chromosome migration and symmetry breaking in oocytes

    Science.gov (United States)

    Yi, Kexi; Rubinstein, Boris; Unruh, Jay R.; Guo, Fengli; Slaughter, Brian D.

    2013-01-01

    Polar body extrusion during oocyte maturation is critically dependent on asymmetric positioning of the meiotic spindle, which is established through migration of the meiosis I (MI) spindle/chromosomes from the oocyte interior to a subcortical location. In this study, we show that MI chromosome migration is biphasic and driven by consecutive actin-based pushing forces regulated by two actin nucleators, Fmn2, a formin family protein, and the Arp2/3 complex. Fmn2 was recruited to endoplasmic reticulum structures surrounding the MI spindle, where it nucleated actin filaments to initiate an initially slow and poorly directed motion of the spindle away from the cell center. A fast and highly directed second migration phase was driven by actin-mediated cytoplasmic streaming and occurred as the chromosomes reach a sufficient proximity to the cortex to activate the Arp2/3 complex. We propose that decisive symmetry breaking in mouse oocytes results from Fmn2-mediated perturbation of spindle position and the positive feedback loop between chromosome signal-induced Arp2/3 activation and Arp2/3-orchestrated cytoplasmic streaming that transports the chromosomes. PMID:23439682

  12. Green light drives leaf photosynthesis more efficiently than red light in strong white light: revisiting the enigmatic question of why leaves are green.

    Science.gov (United States)

    Terashima, Ichiro; Fujita, Takashi; Inoue, Takeshi; Chow, Wah Soon; Oguchi, Riichi

    2009-04-01

    The literature and our present examinations indicate that the intra-leaf light absorption profile is in most cases steeper than the photosynthetic capacity profile. In strong white light, therefore, the quantum yield of photosynthesis would be lower in the upper chloroplasts, located near the illuminated surface, than that in the lower chloroplasts. Because green light can penetrate further into the leaf than red or blue light, in strong white light, any additional green light absorbed by the lower chloroplasts would increase leaf photosynthesis to a greater extent than would additional red or blue light. Based on the assessment of effects of the additional monochromatic light on leaf photosynthesis, we developed the differential quantum yield method that quantifies efficiency of any monochromatic light in white light. Application of this method to sunflower leaves clearly showed that, in moderate to strong white light, green light drove photosynthesis more effectively than red light. The green leaf should have a considerable volume of chloroplasts to accommodate the inefficient carboxylation enzyme, Rubisco, and deliver appropriate light to all the chloroplasts. By using chlorophylls that absorb green light weakly, modifying mesophyll structure and adjusting the Rubisco/chlorophyll ratio, the leaf appears to satisfy two somewhat conflicting requirements: to increase the absorptance of photosynthetically active radiation, and to drive photosynthesis efficiently in all the chloroplasts. We also discuss some serious problems that are caused by neglecting these intra-leaf profiles when estimating whole leaf electron transport rates and assessing photoinhibition by fluorescence techniques.

  13. Thermodynamic Description of Synergy in Solvent Extraction: II Thermodynamic Balance of Driving Forces Implied in Synergistic Extraction.

    Science.gov (United States)

    Rey, J; Bley, M; Dufrêche, J-F; Gourdin, S; Pellet-Rostaing, S; Zemb, T; Dourdain, S

    2017-11-21

    In the second part of this study, we analyze the free energy of transfer in the case of synergistic solvent extraction. This free energy of the transfer of an ion in dynamic equilibrium between two coexisting phases is decomposed into four driving forces combining long-range interactions with the classical complexation free energy associated with the nearest neighbors. We demonstrate how the organometallic complexation is counterbalanced by the cost in free energy related to structural change on the colloidal scale in the solvent phase. These molecular forces of synergistic extraction are driven not only by the entropic term associated with the tight packing of electrolytes in the solvent and by the free energy cost of coextracting water toward the hydrophilic core of the reverse aggregates present but also by the entropic costs in the formation of the reverse aggregate and by the interfacial bending energy of the extractant molecules packed around the extracted species. Considering the sum of the terms, we can rationalize the synergy observed, which cannot be explained by classical extraction modeling. We show an industrial synergistic mixture combining an amide and a phosphate complexing site, where the most efficient/selective mixture is observed for a minimal bending energy and maximal complexation energy.

  14. Supply Chain Management as a Driving Force for Generating Competitive Advantage for Dairy Companies

    Directory of Open Access Journals (Sweden)

    Irina Olegovna Poleshkina

    2016-11-01

    Full Text Available The study aims to uncover the reserves to generate competitive advantages for the participants of the market of perishables in the case of the dairy sector due to the formation of effective supply chains, as this category of goods is the most demanding in terms of periods and conditions of transportation and terms of preservation. The research technique is based on the concepts of value chains and supply chain management. In order to optimize the distribution of functions between the participants of the dairy chain a process-based approach has been applied. The research has revealed the main reasons for high aggregate costs and the places of their formation at each stage of the dairy supply chain. The article proposes the mechanisms to address three main problems arising from the process of building relations between the participants of the dairy supply chain in Russia. These problems are associated with a disproportionate margin distribution between the participants of the chain, with non-compliance of the quality of raw milk with the requirements for the production of specific types of dairy products, and with distrust of the supply chain participants, which increases transaction costs and forces to create reserve supplies which reduce the competitiveness of the whole dairy supply chain in general. In order to improve the competitiveness of all participants in the dairy chain, the article presents several mechanisms for solving these problems. The first is margin distribution based on the costs incurred by each participant of the dairy chain. The second is the use of a mathematical model to determine the assortment of goods of a dairy enterprise on the basis of the incoming volume and quality of raw milk according to the seasonal factor and the demand for dairy products. The third is the feasibility of refusal from the formation of reserve supplies by all participants of the dairy chain, which will not only minimize aggregate costs, but also

  15. High temperature reactor: Driving force to convert CO2 to fuel - HTR2008-58132

    International Nuclear Information System (INIS)

    McCormick, J. L.

    2008-01-01

    The rapidly increasing cost of petroleum products and uncertainty of long-term supply have prompted the U.S. military to aggressively pursue production of alternative fuels (synfuels) such as coal-to-liquids (CTL). U.S. Air Force is particularly active in this effort while the entire military is involved in simultaneously developing fuel specifications for alternative fuels that enable a single fuel for the entire battle space; all ground vehicles, aircraft and fuel cells. By limiting its focus on coal, tar sands and oil shale resources, the military risks violating federal law which requires the use of synfuels that have life cycle greenhouse gas emissions less than or equal to emissions from conventional petroleum fuels. A climate-friendly option would use a high temperature nuclear reactor to split water. The hydrogen (H 2 ) would be used in the reverse water gas shift (RWGS) to react with carbon dioxide (CO 2 ) to produce carbon monoxide (CO) and water. The oxygen (O 2 ) would be fed into a supercritical (SC) coal furnace. The flue gas CO 2 emissions would be stripped of impurities before reacting with H 2 in a RWGS process. Resultant carbon monoxide (CO) is fed, with additional H2, (extra H 2 needed to adjust the stoichiometry: 2 moles H 2 to one mole CO) into a conventional Fischer-Tropsch synthesis (FTS) to produce a heavy wax which is cracked and isomerized and refined to Jet Propulsion 8 (JP-8) and Jet Propulsion 5 (JP-5) fuels. The entire process offers valuable carbon-offsets and multiple products that contribute to lower syn-fuel costs and to comply with the federal limitation imposed on syn-fuel purchases. While the entire process is not commercially available, component parts are being researched; their physical and chemical properties understood and some are state-of-the-art technologies. An international consortium should complete physical, chemical and economic flow sheets to determine the feasibility of this concept that, if pursued, has broad

  16. analysis of spatial-temporal variations and driving force of low cloud in northern China

    Science.gov (United States)

    Niu, Xiaorui; Wang, Shuyu

    2015-04-01

    Cloud plays a crucial role in the climate system, and better understanding of its characteristics and formation mechanism are essential to study the climate system, improve the performance of climate models, and to provide scientific basis on conducting weather modification activities and better using water resources for the purpose of improving the local climate and ecological environment. During 1961 to 2005, decrease trend is detected for the total cloud amount over most parts of northern China, while increase trend is found for the low cloud amount with significant regionality. Both station and ISCCP D2 datasets present similar spatial distributions and interdecadal variation of high cloud. However two datasets show different characters for those of low cloud. Three typical sub-regions are chosen considering their underlying surface features and the temporal trend of low cloud amount, over which the interdecadal variations of low cloud amount in three regions are systematically investigated. The analyses show the strong regionality and seasonality in low cloud amount's temporal variations and trend, and quasi-biannual oscillations are observed in low cloud amount in three regions in the past 45 years. The relationships between 500 hPa circulation indexes and low cloud over the three regions are examined by means of singular value decomposition (SVD). The results show that the summer low cloud amount in Xinjiang is closely related with the Subtropical High, the Tibetan Plateau and Polar Vortex, and the autumn low cloud amount in North China is affected by the area of Subtropical High and intensity of Polar Vortex. For northeast China the controlling factor that affects the spring low cloud amount is the area of Polar Vortex in quadrant ⅳ(30°W-60°E).

  17. Driving forces for changes in geographical distribution of Ixodes ricinus ticks in Europe

    Directory of Open Access Journals (Sweden)

    Medlock Jolyon M

    2013-01-01

    Full Text Available Abstract Many factors are involved in determining the latitudinal and altitudinal spread of the important tick vector Ixodes ricinus (Acari: Ixodidae in Europe, as well as in changes in the distribution within its prior endemic zones. This paper builds on published literature and unpublished expert opinion from the VBORNET network with the aim of reviewing the evidence for these changes in Europe and discusses the many climatic, ecological, landscape and anthropogenic drivers. These can be divided into those directly related to climatic change, contributing to an expansion in the tick’s geographic range at extremes of altitude in central Europe, and at extremes of latitude in Scandinavia; those related to changes in the distribution of tick hosts, particularly roe deer and other cervids; other ecological changes such as habitat connectivity and changes in land management; and finally, anthropogenically induced changes. These factors are strongly interlinked and often not well quantified. Although a change in climate plays an important role in certain geographic regions, for much of Europe it is non-climatic factors that are becoming increasingly important. How we manage habitats on a landscape scale, and the changes in the distribution and abundance of tick hosts are important considerations during our assessment and management of the public health risks associated with ticks and tick-borne disease issues in 21st century Europe. Better understanding and mapping of the spread of I. ricinus (and changes in its abundance is, however, essential to assess the risk of the spread of infections transmitted by this vector species. Enhanced tick surveillance with harmonized approaches for comparison of data enabling the follow-up of trends at EU level will improve the messages on risk related to tick-borne diseases to policy makers, other stake holders and to the general public.

  18. Using geoinformatics and cultural anthropology to identify links between land change, driving forces and actors in the Okavango catchment

    Science.gov (United States)

    Röder, Achim; Stellmes, Marion; Pröpper, Michael; Schneibel, Anne

    2015-04-01

    intensive uses, although the same processes are likely to occur in parts of the Okavango region in the future. Literature: Banwart, S. (2011). "Save our soils." Nature 474: 151-152. Bürgi, M., A. M. Hersperger, et al. (2004). "Driving forces of landscape change - current and new directions." Landscape Ecology 19: 857-868. Butchart, S. H. M., M. Walpole, et al. (2010). "Global Biodiversity: Indicators of Recent Declines." Science 328(5982): 1164-1168. Ellis, E. C. and N. Ramankutty (2008). "Putting people in the map: anthropogenic biomes of the world." Frontiers in Ecology and the Environment 6(8): 439-447. Foley, J. A., R. Defries, et al. (2005). "Global consequences of land use." Science 309(5734): 570-574. Geist, H. J. and E. F. Lambin (2002). "Proximate causes and underlying driving forces of tropical deforestation." BioScience 52(2): 143-150. Haub, C. (2012) World Population Data Sheet. World Population Hein, L., K. van Koppen, et al. (2006). "Spatial scales, stakeholders and the valuation of ecosystem services." Ecological Economics 57: 209-228. Hersperger, A. M., M.-P. Gennaio, et al. (2010). "Linking land change with driving forces and actors: four conceptual models." Ecology and Society 15(4): 1-17. Huang, C., L. S. Davis, et al. (2002). "An assessment of support vector machines for land cover classification." International Journal of Remote Sensing 23(4): 725-749. IPCC (2013). Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. T. F. Stocker, G. Qin, G.-K. Plattneret al. Cambridge, Cambridge University Press. Jönsson, P. and L. Eklundh (2004). "TIMESAT - a program for analysing time-series of satellite sensor data." Computers and Geosciences 30(833-845). Kowalski, B., N. Azebaze, et al. (2013). "Mashare - The People." Biodiversity & Ecology 5: 121-128. Lal, R. (2013). "Climate-strategic agriculture and the water-soil-waste nexus." Journal of Plant

  19. Is personality a driving force for socioeconomic differences in young adults' health care use? A prospective cohort study.

    Science.gov (United States)

    Kraft, Maren; Arts, Koos; Traag, Tanja; Otten, Ferdy; Bosma, Hans

    2017-09-01

    To relate personality characteristics at the age of 12 to socioeconomic differences in health care use in young adulthood. And thereby examining the extent to which socioeconomic differences in the use of health care in young adulthood are based on differences in personality characteristics, independent of the (parental) socioeconomic background. Personality of more than 13,000 Dutch 12-year old participants was related to their health and socioeconomic position after a follow-up of 13 years (when the participants had become young adults). In young adulthood, low socioeconomic status was related to high health care use (e.g. low education -hospital admission: OR = 2.21; low income -GP costs: OR = 1.25). Odds ratios (for the socioeconomic health differences) did not decrease when controlled for personality. In this Dutch sample of younger people, personality appeared not to be a driving force for socioeconomic differences in health care use. Findings thus do not support the personality-related, indirect selection perspective on the explanation of socioeconomic differences in health.

  20. Driving forces in energy-related CO2 emissions in south and east coastal China: commonality and variations

    Science.gov (United States)

    Gao, C.; Liu, Y.; Jin, J.; Wei, T.

    2015-12-01

    East and south coastal China contributes to respectively about 30% and 8% of CO2 emissions in China and the world, and therefore play a critical role in achieving the national goal of emission reduction to mitigate the global warming. It also serves as a benchmark for the less developed regions of China, in terms of achieving the developed world's human development standard under lower per capita emissions. We analyze the driving forces of emissions in this region and their provincial characteristics by applying the Logarithmic Mean Divisia Index method. Our findings show that emissions have been doubled during the period from 2000 to 2012, along with three and two folds increase in economy and energy consumption, respectively. This suggests a persistent lock between economic growth and emissions, even in this socioeconomically advanced region in China. Provincial difference in annual emission growth reveals three distinguished low-carbon developmental stages, owning mainly to the effectiveness of energy efficiency in reducing emission growth. This may explain why previous climate policies have aimed to reduce carbon intensity. These results indicate that targeted measures on enhancing energy efficiency in the short term and de-carbonization of both the economic and energy structure in the long term can lower the emission growth more effectively and efficiently. They also suggest that factor-driven emission reduction strategies and policies are needed in the geographically and socioeconomically similar regions.

  1. Spatiotemporal Pattern and Driving Forces of Arable Land-Use Intensity in China: Toward Sustainable Land Management Using Emergy Analysis

    Directory of Open Access Journals (Sweden)

    Hualin Xie

    2014-05-01

    Full Text Available The level of arable land-use intensity has important impacts on food security and rural sustainable development. Using the emergy method, we investigate the spatial disparities and driving forces of arable land-use intensity in China from 1999 to 2008 at the national, regional and provincial levels. The empirical results show that chemical fertilizer was the largest component of agricultural inputs and that agricultural diesel oil recorded the highest growth rate. The degree of heterogeneities in arable land-use intensity in China showed a decreasing trend, which resulted mainly from the differences among the eastern, northeastern, central and western regions. The regional disparities in labor, pesticides and plastic sheeting decreased from 1999 to 2008. The per capita annual net incomes of household operations and the agricultural policies had a significant positive correlation with total inputs, fertilizer inputs, pesticide inputs and agricultural plastic sheeting. In addition, the nonagricultural population had a greater impact on agricultural plastic sheeting. Finally, we suggest that there is an urgent need to focus on the effects of chemical fertilizer and pesticide inputs on the ecological environment. Agricultural support policies should be introduced for the poor agricultural production provinces.

  2. Application of driving force- Pressure- State- Impact- Response (DPSIR Framework for Analyzing the Human habitat in City of Tehran

    Directory of Open Access Journals (Sweden)

    Esmail Salehi

    2015-09-01

    Full Text Available Human habitat change is a complicated issue that many factors play different roles in its formation and distribution. Considering this complication, a more comprehensive and holistic approach is needed for a better understanding and management of those factors. The causal frameworks are among systemic and integrated methods for addressing the causes of environmental problems and the relationships that exist between the environmental systems for proposing proper solutions. The DPSIR model is a functional analysis framework to depict the cause-effect relationships that exist in creating environmental problems. Tehran is one of the major megacities in the Middle East that faces environmental consequences of over population and unplanned urban sprawl, and because of its location in arid region, its vulnerable to rise of environmental problem. In this research, by using the DPSIR framework, different aspects of habitat condition of Tehran are analyzed and later with the help of this conceptual framework, strategies for controlling urban environment. The results show that urbanization is the major driving force that is induced by overpopulation and the need for further urban sprawl, which cause pressure on natural resources. The state of housing and rapid land use changes have brought about unfavorable living conditions that result in unfavorable impacts on public health and safety, which are the results of ineffective policies and solutions.

  3. Empirical Validation of a Hypothesis of the Hormetic Selective Forces Driving the Evolution of Longevity Regulation Mechanisms

    Directory of Open Access Journals (Sweden)

    Alejandra Gomez-Perez

    2016-12-01

    Full Text Available Exogenously added lithocholic bile acid and some other bile acids slow down yeast chronological aging by eliciting a hormetic stress response and altering mitochondrial functionality. Unlike animals, yeast cells do not synthesize bile acids. We therefore hypothesized that bile acids released into an ecosystem by animals may act as interspecies chemical signals that generate selective pressure for the evolution of longevity regulation mechanisms in yeast within this ecosystem. To empirically verify our hypothesis, in this study we carried out a 3-step process for the selection of long-lived yeast species by a long-term exposure to exogenous lithocholic bile acid. Such experimental evolution yielded 20 long-lived mutants, 3 of which were capable of sustaining their considerably prolonged chronological lifespans after numerous passages in medium without lithocholic acid. The extended longevity of each of the 3 long-lived yeast species was a dominant polygenic trait caused by mutations in more than two nuclear genes. Each of the 3 mutants displayed considerable alterations to the age-related chronology of mitochondrial respiration and showed enhanced resistance to chronic oxidative, thermal and osmotic stresses. Our findings empirically validate the hypothesis suggesting that hormetic selective forces can drive the evolution of longevity regulation mechanisms within an ecosystem.

  4. The Driving Forces for the Practice of Strategic Planning in SMEs: Evidence from Harare Metropolitan Province, Zimbabwe

    Directory of Open Access Journals (Sweden)

    Maxwell Sandada

    2016-08-01

    Full Text Available Despite Zimbabwe sharing with the rest of the world, the notion that SMEs are the impeccable engines to economic revival, growth and development, many of the nation`s SMEs are plagued with high failure rates. Previous studies carried out in most foreign countries suggested that the high failure rate of SMEs was attributable to lack of strategic planning among a host of other factors. Against this backdrop, the purpose of this study was to examine the driving forces for the practice of strategic planning in SMEs. A quantitative cross sectional study was conducted among active SMEs who are registered with the Ministry of Small and Medium Enterprises and Cooperative Development in Zimbabwe. The study revealed that globalisation, business ownership motivations, environmental dynamism and innovation & technological advancement have a positive and statistically significant influence on the adoption or practice of strategic planning among SMEs. The study has important implications for the practice and implementation of strategic planning among SMEs especially in the context of a developing country such as Zimbabwe.

  5. Improved theoretical approximation for the ion drag force in collisionless plasma with strong ion-grain coupling

    International Nuclear Information System (INIS)

    Khrapak, S. A.; Nosenko, V.; Morfill, G. E.; Merlino, R.

    2009-01-01

    We point out a deficiency in our previous analytic calculation of the ion drag force for conditions of the experiment by Nosenko et al. [Phys. Plasmas 14, 103702 (2007)]. An inaccurate approximation is corrected and the ion drag force is recalculated. The improved model yields better overall agreement with the experimental results as compared to the original calculation.

  6. Flexible polyelectrolyte chain in a strong electrolyte solution: Insight into equilibrium properties and force-extension behavior from mesoscale simulation

    Science.gov (United States)

    Malekzadeh Moghani, Mahdy; Khomami, Bamin

    2016-01-01

    Macromolecules with ionizable groups are ubiquitous in biological and synthetic systems. Due to the complex interaction between chain and electrostatic decorrelation lengths, both equilibrium properties and micro-mechanical response of dilute solutions of polyelectrolytes (PEs) are more complex than their neutral counterparts. In this work, the bead-rod micromechanical description of a chain is used to perform hi-fidelity Brownian dynamics simulation of dilute PE solutions to ascertain the self-similar equilibrium behavior of PE chains with various linear charge densities, scaling of the Kuhn step length (lE) with salt concentration cs and the force-extension behavior of the PE chain. In accord with earlier theoretical predictions, our results indicate that for a chain with n Kuhn segments, lE ˜ cs-0.5 as linear charge density approaches 1/n. Moreover, the constant force ensemble simulation results accurately predict the initial non-linear force-extension region of PE chain recently measured via single chain experiments. Finally, inspired by Cohen's extraction of Warner's force law from the inverse Langevin force law, a novel numerical scheme is developed to extract a new elastic force law for real chains from our discrete set of force-extension data similar to Padè expansion, which accurately depicts the initial non-linear region where the total Kuhn length is less than the thermal screening length.

  7. Land use change and its driving forces toward mutual conversion in Zhangjiakou City, a farming-pastoral ecotone in Northern China.

    Science.gov (United States)

    Liu, Chao; Xu, Yueqing; Sun, Piling; Huang, An; Zheng, Weiran

    2017-09-14

    Land use/cover change (LUCC), a local environmental issue of global importance, and its driving forces have been crucial issues in geography and environmental research. Previous studies primarily focused on major driving factors in various land use types, with few explorations of differences between driving forces of mutual land use type conversions, especially in fragile eco-environments. In this study, Zhangjiakou City, in a farming-pastoral ecotone in Northern China, was taken as an example to analyze land use change between 1989 and 2015, and explore the driving forces of mutual land use type conversions using canonical correlation analysis. Satellite images and government statistics, including social-economic and natural data, were used as sources. Arable land, forestland, and grassland formed the main land use structure. From 1989 to 2015 forestland, orchard land, and construction land significantly increased, while arable land, grassland, unused land, and water areas decreased. Conversions from grassland to forestland; from arable land to orchard land, forestland and construction land; and from unused land to grassland and forestland were the primary land use changes. Among these, the conversion from grassland to forestland had the highest ranking. Average annual precipitation and per capita net income of rural residents positively affected the conversion of arable land to forestland and unused land to grassland. GDP, total population, and urbanization rate contributed most significantly to converting arable land to construction land; total retail sales of social consumer goods, average annual temperature, and GDP had important positive influences in converting arable land to orchard land.

  8. Estimation of Longitudinal Force and Sideslip Angle for Intelligent Four-Wheel Independent Drive Electric Vehicles by Observer Iteration and Information Fusion.

    Science.gov (United States)

    Chen, Te; Chen, Long; Xu, Xing; Cai, Yingfeng; Jiang, Haobin; Sun, Xiaoqiang

    2018-04-20

    Exact estimation of longitudinal force and sideslip angle is important for lateral stability and path-following control of four-wheel independent driven electric vehicle. This paper presents an effective method for longitudinal force and sideslip angle estimation by observer iteration and information fusion for four-wheel independent drive electric vehicles. The electric driving wheel model is introduced into the vehicle modeling process and used for longitudinal force estimation, the longitudinal force reconstruction equation is obtained via model decoupling, the a Luenberger observer and high-order sliding mode observer are united for longitudinal force observer design, and the Kalman filter is applied to restrain the influence of noise. Via the estimated longitudinal force, an estimation strategy is then proposed based on observer iteration and information fusion, in which the Luenberger observer is applied to achieve the transcendental estimation utilizing less sensor measurements, the extended Kalman filter is used for a posteriori estimation with higher accuracy, and a fuzzy weight controller is used to enhance the adaptive ability of observer system. Simulations and experiments are carried out, and the effectiveness of proposed estimation method is verified.

  9. Changes in quality management for light water reactor fuel manufacturing: A utility's view of driving forces and status

    International Nuclear Information System (INIS)

    Huettmann, A.; Skusa, J.; Ketteler, M.

    2000-01-01

    Quality management in LWR fuel manufacturing for the use in German reactors is based on international guidelines and national/local authority requirements defined in operational licenses. The quality management is twofold and comprises a quality assurance system and the check of manufacturing documents including witnessing of fabrication processes and inspections. Utility and authority appointed technical expert witness manufacturing and take part in inspections performed by the manufacturer where the scope is strictly defined and does not provide possibilities of flexible responses to manufacturing occurrences. For future developments in quality management HEW supports strengthening the ideas of quality planning. Analysis of all factors influencing fuel reliability shall be performed prior to manufacturing. This will increase the efforts in reviewing of drawings and specifications. Included here shall be a review of processes that will be used in manufacturing. The qualification and robustness of processes shall be demonstrated with special qualification programs and analysis of manufacturing statistics. Instead of product/project related inspections the use of all manufacturing data will provide a complete picture of the manufacturing quality. By applying statistical methods it will be possible to identify trends in manufacturing before deviations occur. So the basic driving force to implement statistical process control for the utilities is the wish to get comprehensive information of delivered quality, whereas for manufacturers it might be to increase production yields and thus to lower costs. The introduction and full use of statistical process control requires open information about manufacturing processes and inspection results by the manufacturers. This might include data judged to be economically sensitive. It also requires changes in attitude at the utilities and appointed experts. HEW has started to review and change internal guidelines to allow

  10. Driving forces and their contribution to the recent decrease in sediment flux to ocean of major rivers in China.

    Science.gov (United States)

    Li, Tong; Wang, Shuai; Liu, Yanxu; Fu, Bojie; Zhao, Wenwu

    2018-09-01

    Understanding the mechanisms behind land-ocean sediment transport processes is crucial, due to the resulting impacts on the sustainable management of water and soil resources. This study investigated temporal trends and historical phases of sediment flux delivered to the sea by nine major rivers in China, while also quantifying the contribution of key anthropogenic and natural driving forces. During the past six decades, sediment flux from these nine major rivers exhibited a statistically significant negative trend, decreasing from 1.92Gtyr -1 during 1954-1968 to 1.39Gtyr -1 , 0.861Gtyr -1 and 0.335Gtyr -1 during 1969-1985, 1986-1999 and 2000-2016, respectively. We used a recently developed Sediment Identity approach and found that the sharp decrease in sediment load observed across China was mainly (~95%) caused by a reduction in sediment concentration. Reservoir construction exerted the strongest influence on land-ocean sediment fluxes, while soil conservation measures represented a secondary driver. Before 1999, soil erosion was not controlled effectively in China and reservoirs, especially large ones, played a dominant role in reducing riverine sediments. After 1999, soil erosion has gradually been brought under control across China, so that conservation measures directly accounted for ~40% of the observed decrease in riverine sediments. With intensifying human activities, it is predicted that the total sediment flux delivered to the sea by the nine major rivers will continue to decrease in the coming decades, although at a slower rate, resulting in severe challenges for the sustainable management of drainage basins and river deltas. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. DropBot: An open-source digital microfluidic control system with precise control of electrostatic driving force and instantaneous drop velocity measurement

    International Nuclear Information System (INIS)

    Fobel, Ryan; Fobel, Christian; Wheeler, Aaron R.

    2013-01-01

    We introduce DropBot: an open-source instrument for digital microfluidics (http://microfluidics.utoronto.ca/dropbot). DropBot features two key functionalities for digital microfluidics: (1) real-time monitoring of instantaneous drop velocity (which we propose is a proxy for resistive forces), and (2) application of constant electrostatic driving forces through compensation for amplifier-loading and device capacitance. We anticipate that this system will enhance insight into failure modes and lead to new strategies for improved device reliability, and will be useful for the growing number of users who are adopting digital microfluidics for automated, miniaturized laboratory operation.

  12. Contrasting evolution patterns between glacier-fed and non-glacier-fed lakes in the central Tibetan Plateau and driving force analysis

    Science.gov (United States)

    Song, C.; Sheng, Y.

    2015-12-01

    High-altitude lakes in the Tibetan Plateau (TP) showed strong spatio-temporal variability during past decades. The lake dynamics can be associated with several key factors including lake type, supply of glacial meltwater, local climate variations. It is important to differentiate these factors when analyzing the driving force of lakes dynamics. With a focus on lakes over the Tanggula Mountains of the central TP, this study investigates the temporal evolution patterns of lake area and water level of different types: glacier-fed closed lake, non-glacier-fed closed lake and upstream lake (draining into closed lakes). We collected all available Landsat archive data and quantified the inter-annual variability of lake extents. Results show accelerated expansions of both glacier-fed and non-glacier-fed lakes during 1970s-2013, and different temporal patterns of the two types of lakes: the non-glacier-fed lakes displayed a batch-wise growth pattern, with obvious growth in 2002, 2005 and 2011 and slight changes in other years, while glacier-fed lakes showed steady expanding tendency. The contrasting patterns are confirmed by the distinction of lake level change between the two groups derived from satellite altimetry during 2003-2009. The upstream lakes remained largely stable due to natural drainage regulation. The intermittent expansions for non-glacier-fed lakes were found to be related to excessive precipitation events and positive "precipitation-evaporation". In contrast, glacier-fed lake changes showed weak correlations with precipitation variations, which imply a joint contribution from glacial meltwater to water budgets. A simple estimation reveals that the increased water storage for all of examined lakes contributed from precipitation/evaporation (0.31±0.09 Gt/yr) slightly overweighed the glacial meltwater supply (0.26±0.08 Gt/yr).

  13. Photoinduced electron transfer in covalent ruthenium-anthraquinone dyads: relative importance of driving-force, solvent polarity, and donor-bridge energy gap.

    Science.gov (United States)

    Hankache, Jihane; Wenger, Oliver S

    2012-02-28

    Four rigid rod-like molecules comprised of a Ru(bpy)(3)(2+) (bpy = 2,2'-bipyridine) photosensitizer, a 9,10-anthraquinone electron acceptor, and a molecular bridge connecting the two redox partners were synthesized and investigated by optical spectroscopic and electrochemical means. An attempt was made to assess the relative importance of driving-force, solvent polarity, and bridge variation on the rates of photoinduced electron transfer in these molecules. Expectedly, introduction of tert-butyl substituents in the bipyridine ligands of the ruthenium complex and a change in solvent from dichloromethane to acetonitrile lead to a significant acceleration of charge transfer rates. In dichloromethane, photoinduced electron transfer is not competitive with the inherent excited-state deactivation processes of the photosensitizer. In acetonitrile, an increase in driving-force by 0.2 eV through attachment of tert-butyl substituents to the bpy ancillary ligands causes an increase in electron transfer rates by an order of magnitude. Replacement of a p-xylene bridge by a p-dimethoxybenzene spacer entails an acceleration of charge transfer rates by a factor of 3.5. In the dyads from this study, the relative order of importance of individual influences on electron transfer rates is therefore as follows: solvent polarity ≥ driving-force > donor-bridge energy gap.

  14. Local deforestation patterns and their driving forces of tropical dry forest in two municipalities in Southern Oaxaca, Mexico (1985-2006

    Directory of Open Access Journals (Sweden)

    L. Galicia

    2016-11-01

    Full Text Available The tropical dry forest is an ecosystem that is undergoing rapid changes. Although global driving forces behind these changes have been addressed at a local scale, spatio-temporal dynamics are still largely unknown. The main objective of this study was to identify the causes governing the dynamics of changes in land use and land cover in the tropical dry forest in two municipalities in Southern México. Satellite imagery and air photographs were used in a GIS context to produce maps of land use and land cover for 1985, 1995 and 2006. A number of statistical methods (Markov chains, general lineal models and regression tree analysis were applied to identify the proximate and the underlying causes of deforestation, agriculture being the most important one. When agriculture is mainly for self consumption, topographic factors determine its location. Increasing job opportunities in the tourism sector has resulted in the abandonment of agricultural land; consequently, the forest has recovered. Different studies have examined the dynamics of local deforestation and its driving forces in México; however, this study considered both spatial and temporal elements in order to identify the most important underlying driving forces of deforestation and its dynamics at local scale, and also compared two neighboring municipalities.

  15. Strong interactions

    International Nuclear Information System (INIS)

    Froissart, Marcel

    1976-01-01

    Strong interactions are introduced by their more obvious aspect: nuclear forces. In hadron family, the nucleon octet, OMEGA - decuplet, and quark triply are successively considered. Pion wave having been put at the origin of nuclear forces, low energy phenomena are described, the force being explained as an exchange of structure corresponding to a Regge trajectory in a variable rotating state instead of the exchange of a well defined particle. At high energies the concepts of pomeron, parton and stratons are introduced, pionization and fragmentation are briefly differentiated [fr

  16. Polarization-dependent force driving the Eg mode in bismuth under optical excitation: comparison of first-principles theory with ultra-fast x-ray experiments

    Science.gov (United States)

    Fahy, Stephen; Murray, Eamonn

    2015-03-01

    Using first principles electronic structure methods, we calculate the induced force on the Eg (zone centre transverse optical) phonon mode in bismuth immediately after absorption of a ultrafast pulse of polarized light. To compare the results with recent ultra-fast, time-resolved x-ray diffraction experiments, we include the decay of the force due to carrier scattering, as measured in optical Raman scattering experiments, and simulate the optical absorption process, depth-dependent atomic driving forces, and x-ray diffraction in the experimental geometry. We find excellent agreement between the theoretical predictions and the observed oscillations of the x-ray diffraction signal, indicating that first-principles theory of optical absorption is well suited to the calculation of initial atomic driving forces in photo-excited materials following ultrafast excitation. This work is supported by Science Foundation Ireland (Grant No. 12/IA/1601) and EU Commission under the Marie Curie Incoming International Fellowships (Grant No. PIIF-GA-2012-329695).

  17. The sixth Euratom framework programme 2003-2006: a driving force for the construction of the Nuclear European Research Area

    International Nuclear Information System (INIS)

    Fernandez-Ruiz, P.; Forsstroem, H.; Goethem, G. van

    2005-01-01

    At the Lisbon 2000 summit, a strategic goal was proposed for the European Union: 'to become the most competitive knowledge-based economy with more and better employment and social cohesion by 2010'. Overall, in particular in the community of nuclear fission research, this EC initiative was well accepted by the main stakeholders. In Europe, the main stakeholders (i.e. suppliers and/or demanders) of nuclear research are actually: the research organisations (with mixed public/private funding), the manufacturing industry (or vendors), the utilities (or engineering companies), the regulatory bodies (or technical safety organisations) and the academia (or universities). In response to the Lisbon 2000 objectives, Commissioner P. BUSQUIN launched the concept of European Research Area (ERA) which sets also the frame for the FP-6. In this invited lecture, research and training in nuclear fission are looked at from a nuclear ERA perspective with emphasis on the three success factors of any European integration policy, namely: needs, vision and instruments, that ought to be strongly shared amongst the stakeholders in the EU-25. The following questions are addressed. What is driving the current EU trend towards more research, more education and more training in general? Regarding nuclear fission, in particular, who are the end-users of Euratom 'research and training' and what are their expectations (needs) from EU programmes? Do all stakeholders share the same vision about European research and training in nuclear fission? What are the instruments proposed by the Commission to the end-users to conduct joint research programmes? The above questions are all linked to nuclear knowledge management. It is shown that, in Community research, production of knowledge remains the most important objective, be it to generate products or services. However, dissemination/transfer (e.g. education and training) and exploitation (e.g. innovation) of knowledge become equally important as

  18. Beyond barriers – A case study on driving forces for improved energy efficiency in the foundry industries in Finland, France, Germany, Italy, Poland, Spain, and Sweden

    International Nuclear Information System (INIS)

    Thollander, Patrik; Backlund, Sandra; Trianni, Andrea; Cagno, Enrico

    2013-01-01

    Highlights: • Results are based on a questionnaire in the European foundry industry. • The energy efficiency potential is assed to be 7.5% of the total energy use. • Most important drivers to and barriers for energy efficiency are financial followed by organizational. • EPC is used among 23% of the foundries, third party financing among 12%. • Large energy management improvement potentials are uncovered. - Abstract: Energy management plays an important role in the transformation of industrial energy systems towards improved energy efficiency and increased sustainability. This paper aims to study driving forces for improved energy efficiency in some European energy-intensive foundry industries. The investigation has been conducted as a multiple case study involving 65 foundries located in Finland, France, Germany, Italy, Poland, Spain, and Sweden. The most relevant perceived driving forces were found to be financially related, followed by organizational driving forces. Nevertheless, some differences can be appreciated according to the firm’s size and country. Almost half of the studied foundries lack a long-term energy strategy, about one-fourth stated that they have used Energy Performance Contracting (EPC), and only approximately one in ten foundries have used Third Party Financing (TPF). Among the studied foundries, three out of five have conducted an energy audit. On average, the energy saving potential according to the respondents is stated to be 7.5%. In conclusion, energy management in the European foundry industry, despite increasing energy prices and extensive energy policy actions taken by the EU, still seems to have great improvement potential, calling for future research and policy actions in the field

  19. The effect of electric field geometry on the performance of electromembrane extraction systems: Footprints of a third driving force along with migration and diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Moazami, Hamid Reza [School of Physics and Accelerators, NSTRI, P. O. Box, 11365-8486, Tehran (Iran, Islamic Republic of); Hosseiny Davarani, Saied Saeed, E-mail: ss-hosseiny@sbu.ac.ir [Faculty of Chemistry, Shahid Beheshti University, G. C., 1983963113, Evin, Tehran (Iran, Islamic Republic of); Mohammadi, Jamil; Nojavan, Saeed [Faculty of Chemistry, Shahid Beheshti University, G. C., 1983963113, Evin, Tehran (Iran, Islamic Republic of); Abrari, Masoud [Laser and Plasma Research Institute, Shahid Beheshti University, G. C., 1983963113, Evin, Tehran (Iran, Islamic Republic of)

    2015-09-03

    The distribution of electric field vectors was first calculated for electromembrane extraction (EME) systems in classical and cylindrical electrode geometries. The results showed that supported liquid membrane (SLM) has a general field amplifying effect due to its lower dielectric constant in comparison with aqueous donor/acceptor solutions. The calculated norms of the electric field vector showed that a DC voltage of 50 V can create huge electric field strengths up to 64 kV m{sup −1} and 111 kV m{sup −1} in classical and cylindrical geometries respectively. In both cases, the electric field strength reached its peak value on the inner wall of the SLM. In the case of classical geometry, the field strength was a function of the polar position of the SLM whereas the field strength in cylindrical geometry was angularly uniform. In order to investigate the effect of the electrode geometry on the performance of real EME systems, the analysis was carried out in three different geometries including classical, helical and cylindrical arrangements using naproxen and sodium diclofenac as the model analytes. Despite higher field strength and extended cross sectional area, the helical and cylindrical geometries gave lower recoveries with respect to the classical EME. The observed decline of the signal was proved to be against the relations governing migration and diffusion processes, which means that a third driving force is involved in EME. The third driving force is the interaction between the radially inhomogeneous electric field and the analyte in its neutral form. - Highlights: • Electric field vectors have been calculated in EME systems. • A new driving force has been proposed in EME systems. • EME can be theoretically applied to nonionic polarizable analytes.

  20. The effect of electric field geometry on the performance of electromembrane extraction systems: Footprints of a third driving force along with migration and diffusion

    International Nuclear Information System (INIS)

    Moazami, Hamid Reza; Hosseiny Davarani, Saied Saeed; Mohammadi, Jamil; Nojavan, Saeed; Abrari, Masoud

    2015-01-01

    The distribution of electric field vectors was first calculated for electromembrane extraction (EME) systems in classical and cylindrical electrode geometries. The results showed that supported liquid membrane (SLM) has a general field amplifying effect due to its lower dielectric constant in comparison with aqueous donor/acceptor solutions. The calculated norms of the electric field vector showed that a DC voltage of 50 V can create huge electric field strengths up to 64 kV m −1 and 111 kV m −1 in classical and cylindrical geometries respectively. In both cases, the electric field strength reached its peak value on the inner wall of the SLM. In the case of classical geometry, the field strength was a function of the polar position of the SLM whereas the field strength in cylindrical geometry was angularly uniform. In order to investigate the effect of the electrode geometry on the performance of real EME systems, the analysis was carried out in three different geometries including classical, helical and cylindrical arrangements using naproxen and sodium diclofenac as the model analytes. Despite higher field strength and extended cross sectional area, the helical and cylindrical geometries gave lower recoveries with respect to the classical EME. The observed decline of the signal was proved to be against the relations governing migration and diffusion processes, which means that a third driving force is involved in EME. The third driving force is the interaction between the radially inhomogeneous electric field and the analyte in its neutral form. - Highlights: • Electric field vectors have been calculated in EME systems. • A new driving force has been proposed in EME systems. • EME can be theoretically applied to nonionic polarizable analytes.

  1. Smart management - Driving forces and conditions for the development of advanced electricity networks; Smart ledning - Drivkrafter och foerutsaettningar foer utveckling av avancerade elnaet

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, Oerjan; Staahl, Benjamin (Blue Inst., Stockholm (Sweden))

    2011-02-15

    This report describes the development of Intelligent Networks, or Smart Grids. It is divided into two sections. The first section highlights the basics of what is called 'smart' grid technology, what the underlying driving forces are and how the conditions for market looks like. It also depicts the impact on consumers, emerging business logics and ongoing investment and incentives in the world. The first part ends with an operator map of the market. The second part takes a closer look on some key areas and includes a simple reminder of technology related to smart grids

  2. First-principles calculation of the polarization-dependent force driving the Eg mode in bismuth under optical excitation.

    Science.gov (United States)

    Murray, Eamonn; Fahy, Stephen

    2014-03-01

    Using first principles electronic structure methods, we calculate the induced force on the Eg (zone centre transverse optical) phonon mode in bismuth immediately after absorption of polarized light. When radiation with polarization perpendicular to the c-axis is absorbed in bismuth, the distribution of excited electrons and holes breaks the three-fold rotational symmetry and leads to a net force on the atoms in the direction perpendicular to the axis. We calculate the initial excited electronic distribution as a function of photon energy and polarization and find the resulting transverse and longitudinal forces experienced by the atoms. Using the measured, temperature-dependent rate of decay of the transverse force[2], we predict the approximate amplitude of induced atomic motion in the Eg mode as a function of temperature and optical fluence. This work is supported by Science Foundation Ireland and a Marie Curie International Incoming Fellowship.

  3. Driving Forces of Dynamic Changes in Soil Erosion in the Dahei Mountain Ecological Restoration Area of Northern China Based on GIS and RS.

    Science.gov (United States)

    Li, Xiao; Niu, Xiang; Wang, Bing; Gao, Peng; Liu, Yu

    2016-01-01

    Dynamic change in soil erosion is an important focus of regional ecological restoration research. Here, the dynamic changes of soil erosion and its driving forces in the Dahei Mountain ecological restoration area of northern China were analyzed by LANDSAT TM remote sensing captured via geographic information system (GIS) technologies during three typical periods in 2004, 2008 and 2013. The results showed the following: (1) a decrease in intensive erosion and moderate erosion areas, as well as an increase in light erosion areas, was observed during two periods: one from 2004 to 2008 and the other from 2008 to 2013. (2) Between 2004 and 2008, the variation in the range of slight erosion was the largest (24.28%), followed by light erosion and intensive erosion; between 2008 and 2013, the variation in the range of intensive erosion area was the largest (9.89%), followed by slight erosion and moderate erosion. (3) Socioeconomic impact, accompanied by natural environmental factors, was the main driving force underlying the change in soil erosion within the ecological restoration area. In particular, the socioeconomic factors of per capita forest area and land reclamation rate, as well as the natural environmental factor of terrain slope, significantly influenced soil erosion changes within the ecological restoration area.

  4. Driving forces behind the stagnancy of China's energy-related CO2 emissions from 1996 to 1999: the relative importance of structural change, intensity change and scale change

    International Nuclear Information System (INIS)

    Libo Wu; Kaneko, S.; Matsuoka, S.

    2005-01-01

    It is noteworthy that income elasticity of energy consumption in China shifted from positive to negative after 1996, accompanied by an unprecedented decline in energy-related CO 2 emissions. This paper therefore investigate the evolution of energy-related CO 2 emissions in China from 1985 to 1999 and the underlying driving forces, using the newly proposed three-level 'perfect decomposition' method and provincially aggregated data. The province-based estimates and analyses reveal a 'sudden stagnancy' of energy consumption, supply and energy-related CO 2 emissions in China from 1996 to 1999. The speed of a decrease in energy intensity and a slowdown in the growth of average labor productivity of industrial enterprises may have been the dominant contributors to this 'stagnancy'. The findings of this paper point to the highest rate of deterioration of state-owned enterprises in early 1996, the industrial restructuring caused by changes in ownership, the shutdown of small-scale power plants, and the introduction of policies to improve energy efficiency as probable factors. Taking into account the characteristics of those key driving forces, we characterize China's decline of energy-related CO 2 emissions as a short-term fluctuation and incline to the likelihood that China will resume an increasing trend from a lower starting point in the near future. (author)

  5. Structure and relative importance of ponderomotive forces and current drive generated by converted fast waves in pre-heated low aspect ratio tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Cuperman, S.; Bruma, C.; Komoshvili, K

    2003-05-12

    The generation in low aspect ratio tokamaks (LARTs) of ponderomotive forces and non-inductive current drive by the resonant fast wave-plasma interaction with mode conversion to kinetic Alfven waves (KAWs) and subsequent deposition, mainly by resonant electron Landau damping, is considered. The calculations follow the rigorous solution of the full wave equations upon using a dielectric tensor operator consisting of (i) a parallel conductivity including both kinetic effects (collisionless Landau damping on passing electrons) and collisional damping on both trapped electrons and passing electrons+ions and (ii) perpendicular components provided by the resistive two-fluid model equations. The fast waves are launched by an antenna located on the low field side and extending {+-}45 deg. about the equatorial plane. A parametric investigation of the structure and importance of the various components of the ponderomotive forces and current drive generated in START-like plasmas is carried out and their suitability for supplementing the required non-rf toroidal equilibrium current is demonstrated.

  6. Analyzing the driving forces behind CO2 emissions and reduction strategies for energy-intensive sectors in Taiwan, 1996–2006

    International Nuclear Information System (INIS)

    Huang, Yun-Hsun; Wu, Jung-Hua

    2013-01-01

    Between 1996 and 2006, CO 2 emissions in Taiwan increased by approximately 60%, with the industrial sector accounting for 50% of that increase. Among all industrial sectors, iron and steel, petrochemicals, electronics, textiles, pulp and paper and cement accounted for approximately three-quarters of the total industrial CO 2 emissions. Identifying the driving forces behind increased CO 2 emissions in these six sectors could be valuable for the development of effective environmental policy. This study used two-tier KLEM input–output structural decomposition analysis (I-O SDA) to analyze the factors that lead to changes in CO 2 emissions. Empirical results obtained in Taiwan reveal that increased exports level and elevated domestic autonomous final demand level were the main reasons for increases in CO 2 emissions. Technological changes in materials and labor tended to decrease CO 2 emissions, while the power generation mix contributed significantly to the increase. Relevant strategies for reducing CO 2 emissions from energy-intensive sectors are also highlighted. - Highlights: • Identifying the driving forces behind increased CO 2 emissions is important. • This study uses two-tier KLEM I-O SDA to analyze the changes in CO 2 emissions. • Three issues are identified to achieve future CO 2 emissions reduction in Taiwan

  7. Driving forces and barriers to improved energy performance of buildings: an analysis of energy performance of Swedish buildings, 2000-2006

    Energy Technology Data Exchange (ETDEWEB)

    Fuglseth, Bente Beckstroem

    2008-06-15

    The building sector is responsible for a substantial part of energy use and green house gas emissions in Europe. This report explores driving forces and barriers to improved energy performance of buildings, using the Swedish building sector as a case. The development of energy performance of buildings in Sweden from 2000 until 2006 is explored by applying a threefold understanding of energy performance of buildings: substitution from fossil fuels to renewable energy, conversion from electrical heating to thermal energy and reduction in energy demand. Three explanatory approaches are used to analyse driving forces and barriers to improved energy performance: the techno-economic approach stresses the physical aspects of infrastructure and technologies, the institutional approach emphasizes the role of institutional factors, while the regulative approach focuses on formal rules and laws. The study concludes that all factors have promoted substitution of fossil fuels with renewable energy, while they have prevented conversion from electrical heating to thermal energy and reduction in energy demand. (author). 95 refs

  8. A piezo motor based on a new principle with high output force, rigidity and integrity: The Tuna Drive

    Science.gov (United States)

    Liu, Xiaolong; Lu, Qingyou

    2012-11-01

    We present a linear piezoelectric motor as simple as one piezoelectric scanner tube (PST) spring-clamping a central shaft at both ends with roughly equal clamping forces. The clamping points are aligned with ±X electrodes at one end and ±Y electrodes at the other end. Thus, the ±X (or ±Y) push-pull motions of the PST can cause the push-pull motions of the clamping points on the shaft (called push-pull rubbing), which reduces the total dynamic friction force at one (or the other) end of the PST. This new piezo motor advances one step by fast push-pull rubbing at one end while slowly retracting the PST followed by fast push-pull rubbing at the other end while slowly elongating the PST. Apart from the obvious advantages of simplicity, rigidity, integrity, etc., we will also show that this motor can produce a large output force, which we believe is because of the huge drop of the clamping friction force when the push-pull rubbing occurs.

  9. Up-regulation of Rho/ROCK signaling in sarcoma cells drives invasion and increased generation of protrusive forces

    Czech Academy of Sciences Publication Activity Database

    Rosel, D.; Brabek, J.; Tolde, O.; Mierke, C.T.; Zitterbart, D.P.; Raupach, C.; Bicanova, K.; Kollmannsberger, P.; Pánková, D.; Veselý, Pavel; Folk, P.; Fabry, B.

    2008-01-01

    Roč. 6, č. 9 (2008), s. 1410-1420 ISSN 1541-7786 Institutional research plan: CEZ:AV0Z50520514 Keywords : Rho kinase ROCK * traction force microscopy * ameboid invasion Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.533, year: 2008

  10. Varieties of flood risk governance in Europe: How do countries respond to driving forces and what explains institutional change?

    NARCIS (Netherlands)

    Wiering, M.A.; Kaufmann, M.; Mees, H.; Schellenberger, T.; Ganzevoort, W.; Hegger, D.L.T.; Larrue, C.; Matczak, P.

    2017-01-01

    Floods are challenging the resilience of societies all over the world. In many countries there are discussions on diversifying the strategies for flood risk management, which implies some sort of policy change. To understand the possibilities of such change, a thorough understanding of the forces of

  11. The Conflicting Forces Driving Future Avionics Acquisition (Les Arguments Contradictoires pour les Futurs Achats d’Equipements d’Avionique)

    Science.gov (United States)

    1991-09-01

    Sep 1983 "Reliability Parameter of Additive Plated Through Hoics," William E. Greiner , Kollmorgen Corporation, 1rAnnual "Guidelines for Surface Mounting...Militare Etat-Major delIs Force Adienne Ufficio del Delegato Nazionaic all*AGARD Quartier Reine Elisabeth Aeroporto Pratica di Mare Rue d’Evere, 1140

  12. Orbital-scale nonlinear response of East Asian summer monsoon to its potential driving forces in the late Quaternary

    Science.gov (United States)

    Yi, Liang; Shi, Zhengguo; Tan, Liangcheng; Deng, Chenglong

    2018-03-01

    We conducted a statistical study to characterize the nonlinear response of the East Asian summer monsoon (EASM) to its potential forcing factors over the last 260 ka on orbital timescales. We find that both variation in solar insolation and global ice volume were responsible for the nonlinear forcing of orbital-scale monsoonal variations, accounting for 80% of the total variance. Specifically, EASM records with dominated precession variance exhibit a more sensitive response to changes in solar insolation during intervals of enhanced monsoon strength, but are less sensitive during intervals of reduced monsoon strength. In the case of global ice volume with 100-ka variance, this difference is not one of sensitivity but rather a difference in baseline conditions, such as the relative areas of land and sea which affected the land-sea thermal gradient. We therefore suggest that EASM records with dominated precession variance recorded the signal of a shift in the location of the Inter-tropical Convergence Zone, and the associated changes in the incidence of torrential rainfall; while for proxies with dominated 100-ka variance, it recorded changes in the land-sea thermal gradient via its effects on non-torrential precipitation.

  13. Spontaneous formation of small unilamellar vesicles by pH jump: A pH gradient across the bilayer membrane as the driving force

    International Nuclear Information System (INIS)

    Hauser, H.; Mantsch, H.H.; Casal, H.L.

    1990-01-01

    31 P NMR and infrared spectroscopic methods have been used to study the formation of small unilamellar vesicles by the pH-jump method. It is shown that increasing the pH of different lamellar phospholipid dispersions (phosphatidic acids and phosphatidylserines) induces a pH gradient. This pH gradient is estimated to be 4 ± 1 pH units, and its direction is such that the inner monolayer of the vesicles is at lower pH. There is spectroscopic evidence for tighter packing of the lipid hydrocarbon chains in the inner monolayer, probably due to the constraints imposed by the high curvature of the small vesicles formed. These results are discussed in terms of the driving force of the spontaneous vesiculation

  14. Dehydrogenation Kinetics and Modeling Studies of MgH2 Enhanced by Transition Metal Oxide Catalysts Using Constant Pressure Thermodynamic Driving Forces

    Directory of Open Access Journals (Sweden)

    Saidi Temitope Sabitu

    2012-06-01

    Full Text Available The influence of transition metal oxide catalysts (ZrO2, CeO2, Fe3O4 and Nb2O5 on the hydrogen desorption kinetics of MgH2 was investigated using constant pressure thermodynamic driving forces in which the ratio of the equilibrium plateau pressure (pm to the opposing plateau (pop was the same in all the reactions studied. The results showed Nb2O5 to be vastly superior to other catalysts for improving the thermodynamics and kinetics of MgH2. The modeling studies showed reaction at the phase boundary to be likely process controlling the reaction rates of all the systems studied.

  15. Driving forces of redistribution of elements during quasicrystalline phase formation under heating of mechanically alloyed Al65Cu23Fe12 powder

    Science.gov (United States)

    Tcherdyntsev, V. V.; Kaloshkin, S. D.; Shelekhov, E. V.; Principi, G.; Rodin, A. O.

    2008-02-01

    Al65Cu23Fe12 alloys were prepared by ball milling of the elemental powders mixture. Phase and structural transformations at heating of as-milled powders were investigated by X-ray diffraction analysis. Precision analysis of Mössbauer spectra was performed to check the adequacy of the fitting of X-ray diffraction patterns. The results were compared with the data of differential scanning and solution calorimetry, as well as with the thermodynamic literature data, in order to estimate the driving forces of redistribution of elements that preceded the formation of single-phase quasicrystalline structure. The heat of elements mixing, which is positive for Cu-Fe system and negative for Al-Fe and Al-Cu systems, was supposed to be a decisive factor for phase transformations during heating of the alloy. The correlation between sequence of phase transformations during heating and the thermodynamic data was discussed and the scheme describing phase transformations observed was proposed.

  16. Bimodal atomic force microscopy driving the higher eigenmode in frequency-modulation mode: Implementation, advantages, disadvantages and comparison to the open-loop case.

    Science.gov (United States)

    Ebeling, Daniel; Solares, Santiago D

    2013-01-01

    We present an overview of the bimodal amplitude-frequency-modulation (AM-FM) imaging mode of atomic force microscopy (AFM), whereby the fundamental eigenmode is driven by using the amplitude-modulation technique (AM-AFM) while a higher eigenmode is driven by using either the constant-excitation or the constant-amplitude variant of the frequency-modulation (FM-AFM) technique. We also offer a comparison to the original bimodal AFM method, in which the higher eigenmode is driven with constant frequency and constant excitation amplitude. General as well as particular characteristics of the different driving schemes are highlighted from theoretical and experimental points of view, revealing the advantages and disadvantages of each. This study provides information and guidelines that can be useful in selecting the most appropriate operation mode to characterize different samples in the most efficient and reliable way.

  17. Gibbs energy modelling of the driving forces and calculation of the fcc/hcp martensitic transformation temperatures in Fe-Mn and Fe-Mn-Si alloys

    International Nuclear Information System (INIS)

    Cotes, S.; Fernandez Guillermet, A.; Sade, M.

    1999-01-01

    Very recent, accurate dilatometric measurements of the fcc hcp martensitic transformation (MT) temperatures are used to develop a new thermodynamic description of the fcc and hcp phases in the Fe-Mn-Si system, based on phenomenological models for the Gibbs energy function. The composition dependence of the driving forces for the fcc→hcp and the hcp→fcc MTs is established. Detailed calculations of the MT temperatures are reported, which are used to investigate the systematic effects of Si additions upon the MT temperatures of Fe-Mn alloys. A critical comparison with one of the most recent thermodynamic analyses of the Fe-Mn-Si system, which is due to Forsberg and Agren, is also presented. (orig.)

  18. Analysis of Urban-Rural Land-Use Change during 1995-2006 and Its Policy Dimensional Driving Forces in Chongqing, China

    Directory of Open Access Journals (Sweden)

    Guihua Dong

    2008-02-01

    Full Text Available This paper analyzes the urban-rural land-use change of Chongqing and its policydimensional driving forces from 1995 to 2006, using high-resolution Landsat TM(Thematic Mapper data of 1995, 2000 and 2006, and socio-economic data from bothresearch institutes and government departments. The outcomes indicated that urban-ruralland-use change in Chongqing can be characterized by two major trends: First, thenon-agricultural land increased substantially from 1995 to 2006, thus causing agriculturalland especially farmland to decrease continuously. Second, the aggregation index of urbansettlements and rural settlements shows that local urban-rural development experienced aprocess of changing from aggregation (1995-2000 to decentralization (2000-2006.Chongqing is a special area getting immersed in many important policies, which includethe establishment of the municipality directly under the Central Government, the buildingof Three Gorges Dam Project, the Western China Development Program and theGrain-for-Green Programme, and bring about tremendous influences on its land-usechange. By analyzing Chongqing’s land-use change and its policy driving forces, someimplications for its new policy of ‘Urban-rural Integrated Reform’ are obtained. That ismore attentions need to be paid to curbing excessive and idle rural housing andconsolidating rural construction land, and to laying out a scientific land-use plan for its rural areas taking such rural land-use issues as farmland occupation and rural housing landmanagement into accounts, so as to coordinate and balance the urban-rural development.

  19. Testing strong interaction theories

    International Nuclear Information System (INIS)

    Ellis, J.

    1979-01-01

    The author discusses possible tests of the current theories of the strong interaction, in particular, quantum chromodynamics. High energy e + e - interactions should provide an excellent means of studying the strong force. (W.D.L.)

  20. Electrografting of alkyl films at low driving force by diverting the reactivity of aryl radicals derived from diazonium salts.

    Science.gov (United States)

    Hetemi, Dardan; Kanoufi, Frédéric; Combellas, Catherine; Pinson, Jean; Podvorica, Fetah I

    2014-11-25

    Alkyl and partial perfluoroalkyl groups are strongly attached to carbon surfaces through (i) the abstraction of the iodine atom from an iodoalkane by the sterically hindered 2,6-dimethylphenyl radical and (ii) the reaction of the ensuing alkyl radical with the carbon surface. Since the 2,6-dimethylphenyl radical is obtained at -0.25 V/Ag/AgCl by reducing the corresponding diazonium salt, the electrografting reaction is facilitated by ∼1.7 V by comparison with the direct electrografting of the iodo compounds. Layers of various thicknesses, including monolayers, are obtained by controlling the time duration of the electrolysis. The grafted films are characterized by electrochemistry, IR, XPS, ellipsometry, and water contact angles.

  1. Crystal structure of a trapped catalytic intermediate suggests that forced atomic proximity drives the catalysis of mIPS.

    Science.gov (United States)

    Neelon, Kelly; Roberts, Mary F; Stec, Boguslaw

    2011-12-07

    1-L-myo-inositol-phosphate synthase (mIPS) catalyzes the first step of the unique, de novo pathway of inositol biosynthesis. However, details about the complex mIPS catalytic mechanism, which requires oxidation, enolization, intramolecular aldol cyclization, and reduction, are not fully known. To gain further insight into this mechanism, we determined the crystal structure of the wild-type mIPS from Archaeoglobus fulgidus at 1.7 Å, as well as the crystal structures of three active-site mutants. Additionally, we obtained the structure of mIPS with a trapped 5-keto-glucose-6-phosphate intermediate at 2 Å resolution by a novel (to our knowledge) process of activating the crystal at high temperature. A comparison of all of the crystal structures of mIPS described in this work suggests a novel type of catalytic mechanism that relies on the forced atomic proximity of functional groups. The lysine cluster is contained in a small volume in the active site, where random motions of these side chains are responsible for the progress of the complex multistep reaction as well as for the low rate of catalysis. The mechanism requires that functional groups of Lys-274, Lys-278, Lys-306, and Lys-367 assume differential roles in the protonation/deprotonation steps that must occur during the mIPS reaction. This mechanism is supported by the complete loss of activity of the enzyme caused by the Leu-257 mutation to Ala that releases the lysine containment. Copyright © 2011 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  2. Driving forces of the diel distribution of phytoplankton functional groups in a shallow tropical lake (Lake Monte Alegre, Southeast Brazil

    Directory of Open Access Journals (Sweden)

    LM. Rangel

    Full Text Available Phytoplankton vertical and diel dynamics in a small shallow lake (Lake Monte Alegre, Ribeirão Preto, state of São Paulo were investigated in two climatological periods: July 2001 (cool-dry season and March 2002 (warm-rainy season. Monte Alegre is a eutrophic reservoir, with a warm polymictic discontinuous circulation pattern. The lake was thermally stratified in both periods, although dissolved oxygen varied less in the cool-dry period. Phytoplankton biomass was higher in the warm-rainy season and the vertical distribution was stratified in both seasons. Flagellate groups (Lm, Y, W1 and W2 and functional groups typical of shallow eutrophic environments (J, X1 and Sn were important throughout the study period. The lake's thermal pattern strongly influenced the vertical distribution of the phytoplankton community in both periods. Biomass, functional groups and size classes of phytoplankton also were determined by the presence of more efficient herbivores in the lake, especially during the cool-dry period when phytoplankton biomass decreased.

  3. Mediterranean coastal dune vegetation: Are disturbance and stress the key selective forces that drive the psammophilous succession?

    Science.gov (United States)

    Ciccarelli, Daniela

    2015-11-01

    Plant communities of coastal dunes are distributed along a characteristic sea-inland gradient. Generally, there is a shift from annual and short height species with small leaves in the initial successional stages to perennial tall shrubs with tough leaves in later phases. Assessing the community-weighted mean (CWM) trait values is used in plant ecology to describe ecosystem properties especially during succession. In particular, CSR (Competitive, Stress-tolerant, and Ruderal strategy) classification allows us to explore community functional shifts in terms of disturbance, stress and competition selective forces. The functional basis of the psammophilous succession was studied based on the following questions: (1) Can we circumscribe different functional types among plant species of Mediterranean coastal dunes? (2) How do CWM trait values vary along the environmental sea-inland gradient? (3) What is the relative importance of competition, stress and disturbance in the processes of plant community assembling? (4) Can we postulate that along primary successions there is generally a shift from ruderality to stress-tolerance? An explorative analysis of functional groups was performed by Non-Metric Multidimensional Scaling (NMDS) analysing nine morpho-functional traits measured for 45 taxa from 880 dune plots localised in Tuscany (central Italy, Europe). NMDS ordination showed a scattered distribution of psammophytes that could not be delimited in precise plant functional types. The first NMDS axis has been interpreted as a leaf economics axis because it was correlated to leaf area (LA) and leaf dry matter content (LDMC), while the second one was a plant size axis because of its correlation with canopy height. Along the sea-inland gradient, pioneer plant communities of upper beach were dominated by ruderals (with the lowest values of LDMC and specific leaf area - SLA), well-adapted to the harsh environmental conditions of coastal dunes. More distant from the sea, where

  4. Subatomic forces

    International Nuclear Information System (INIS)

    Sutton, C.

    1989-01-01

    Inside the atom, particles interact through two forces which are never felt in the everyday world. But they may hold the key to the Universe. These ideas on subatomic forces are discussed with respect to the strong force, the electromagnetic force and the electroweak force. (author)

  5. Community Drive

    DEFF Research Database (Denmark)

    Magnussen, Rikke

    2018-01-01

    Schools and educational institutions are challenged by not adequately educating students for independent knowledge collaboration and solving of complex societal challenges (Bundsgaard & Hansen, 2016; Slot et al., 2017). As an alternative strategy to formal learning has Community-driven research...... opportunity to break boundaries between research institutions and surrounding communities through the involvement of new types of actors, knowledge forms and institutions (OECD, 2011). This paper presents the project Community Drive a three year cross disciplinary community-driven game– and data-based project....... In the paper we present how the project Community Drive initiated in May 2018 is based on results from pilot projects conducted from 2014 – 2017. Overall these studies showed that it is a strong motivational factor for students to be given the task to change their living conditions through redesign...

  6. Nature of macroeconomic equilibrium and driving force of economic cycles in the light of difference between money and exergy forms in cost estimations

    Energy Technology Data Exchange (ETDEWEB)

    Bandura, A.V. [National Politechnical Univ., Kiev (Ukraine); Brodianskii, V.M. [Moscow Power Engineering Inst. Technical Univ. (Russian Federation)

    1996-11-01

    The main problem of exergy application directly in economic analysis is to find valid correlation between money-based cost and exergy based one (including exergy expenses of labour) and to define exergy cost as an economic category among the existing traditional economic ones. The present report is aimed to search the way for this macroeconomic problems` solution. It is demonstrated that exergy-based cost can be recalculated in a monetary form using a coefficient, defined as a ratio between money supply and the total exergy of all natural resources involved in production process, i.e. as a ratio between monetary and exergy bases. The difference between `natural` and current prices (P) can be used directly both for general quantitative characteristics of an economic cycles driving force and for control of market relationship imperfection. It is shown that for the period of time with the positive P, that is, current price is lower than a `natural` one, the recoveries in business cycles are observed. For the period of time with the negative P, that is, current price is higher than a natural one, economic recessions are observed. The moment of time when P = 0 corresponds to the turning point of a business cycle. In such a way the possibility to predict the turning points of business cycles is demonstrated. 14 refs, 2 figs, 2 tabs

  7. Molecular dynamics simulations shed light on the enthalpic and entropic driving forces that govern the sequence specific recognition between netropsin and DNA.

    Science.gov (United States)

    Dolenc, Jozica; Gerster, Sarah; van Gunsteren, Wilfred F

    2010-09-02

    With the aim to gain a better understanding of the various driving forces that govern sequence specific DNA minor groove binding, we performed a thermodynamic analysis of netropsin binding to an AT-containing and to a set of six mixed AT/GC-containing binding sequences in the DNA minor groove. The relative binding free energies obtained using molecular dynamics simulations and free energy calculations show significant variations with the binding sequence. While the introduction of a GC base pair in the middle or close to the middle of the binding site is unfavorable for netropsin binding, a GC base pair at the end of the binding site appears to have no negative influence on the binding. The results of the structural and energetic analyses of the netropsin-DNA complexes reveal that the differences in the calculated binding affinities cannot be explained solely in terms of netropsin-DNA hydrogen-bonding or interaction energies. In addition, solvation effects and entropic contributions to the relative binding free energy provide a more complete picture of the various factors determining binding. Analysis of the relative binding entropy indicates that its magnitude is highly sequence-dependent, with the ratio |TDeltaDeltaS|/|DeltaDeltaH| ranging from 0.07 for the AAAGA to 1.7 for the AAGAG binding sequence, respectively.

  8. Daylighting as the Driving Force of the Design Process: from the Results of a Survey to the Implementation into an Advanced Daylighting Project

    Directory of Open Access Journals (Sweden)

    Valerio R.M. Lo Verso

    2014-12-01

    Full Text Available This paper presents a study for the transformation of an industrial area in Turin, Italy. The area hosts two buildings (one of which appointed as listed to be transformed into dwellings. A synergic approach was adopted which combined expertise from architecture, social-economics, psychology and building physics sciences. Building physics sciences lead the research team. A user-centered design was pursued, using a bottom-up approach. A specifically developed questionnaire was submitted on-line to potential users. The survey showed that ‘amount of daylight’, ‘size of rooms’, ‘tranquility of the area’ and ‘presence of a private garden’ were perceived by users to be the most positive aspects of both their present and future, ideal home. These results were then implemented into the project. The exploitation of daylight became the driving force of the transformation project. Especially for the listed building, skylights and light wells were designed to bring daylight into the cores of the buildings, which host common spaces such as libraries or study rooms. The amount of daylight was assessed through the legislative index of the average daylight factor and through a climate-based modeling approach, calculating dynamic metrics such as the spatial daylight autonomy and the Useful Daylight Illuminance. The paper critically compares and discusses these two approaches. Finally, the energy demand for lighting was also calculated to analyze how the increased exploitation of daylight may imply a reduced need for electricity for lighting.

  9. Very high geothermal gradient in near surface of the Whataroa Valley adjacent to the Alpine Fault: topographic driving forces and permeable mountains

    Science.gov (United States)

    Upton, P.; Sutherland, R.; Townend, J.; Coussens, J.; Capova, L.

    2015-12-01

    The first phase of the Deep Fault Drilling Project (DFDP-1B) yielded a geothermal gradient of 62.6 ± 2.1 °C/km from a depth of 126 m where it intersected the Alpine Fault principal slip surface beneath Gaunt Creek (Sutherland et al. 2012). Ambient fluid pressures in DFDP-2B at Whataroa River were 8-10% above hydrostatic and a geothermal gradient of >130°C/km was determined, the geothermal gradient being considerably higher than we had predicted previously. 3D coupled thermal/fluid flow models have been generated of the Whataroa Valley and the DFDP-2 drill site. Modelling confirms that the following features, present in the Whataroa Valley, are a requirement for a geothermal gradient of >130°C/km at a depth of 1km beneath the valley; high topography, permeability on the order of 10-15 m2 in both the mountains and beneath the valleys to depths of > 1km below the valley floor, and abundant fluid. The high permeability and large topographic driving force leads to abundant meteoric water flowing downward through the mountains, hitting the permeability barrier of the Alpine Fault and being pushed upward into the valleys. The high geothermal gradient of the DFDP-2B borehole implies that the valleys also have a very high permeability which is likely a result of rock damage along the Alpine Fault.

  10. The Driving Forces of Guest Substitution in Gas Hydrates—A Laser Raman Study on CH4-CO2 Exchange in the Presence of Impurities

    Directory of Open Access Journals (Sweden)

    Bettina Beeskow-Strauch

    2012-02-01

    Full Text Available The recovery of CH4 gas from natural hydrate formations by injection of industrially emitted CO2 is considered to be a promising solution to simultaneously access an unconventional fossil fuel reserve and counteract atmospheric CO2 increase. CO2 obtained from industrial processes may contain traces of impurities such as SO2 or NOx and natural gas hydrates may contain higher hydrocarbons such as C2H6 and C3H8. These additions have an influence on the properties of the resulting hydrate phase and the conversion process of CH4-rich hydrates to CO2-rich hydrates. Here we show results of a microscopic and laser Raman in situ study investigating the effects of SO2-polluted CO2 and mixed CH4-C2H6 hydrate on the exchange process. Our study shows that the key driving force of the exchange processes is the establishment of the chemical equilibrium between hydrate phase and the surrounding phases. The exchange rate is also influenced by the guest-to-cavity ratio as well as the thermodynamic stability in terms of p-T conditions of the original and resulting hydrate phase. The most effective molecule exchange is related to structural changes (sI-sII which indicates that hydrate decomposition and reformation processes are the occurring processes.

  11. North America as driving force

    Energy Technology Data Exchange (ETDEWEB)

    Grunwald, Markus

    2012-07-01

    The fact that Europe is comparably small in size and densely populated puts limits to the use of PV solar trackers. But that's no reason for the tracker manufacturers to throw in the towel. Those prepared to take a look abroad may yet feel their hearts beat faster.

  12. The driving force behind all

    International Nuclear Information System (INIS)

    Zischka, A.

    1988-01-01

    The book reviews the history of energy uses in the world, arranging the material into three main sections corresponding to the three historical revolutions in the development of man's capacity to use the energy available in the world for his own purposes. These three mile posts are the mastering and utilization of fire, the Neolithic revolution, and the industrial revolution. The author tells the story excitingly and in a fascinating way explaining the very first steps and the long way mankind took, to achieve the technological systems we have now. Concentrating on the developments and interactions of significance to today's situation, the author presents data and information that brings life into history and fosters independent thinking. Right answers need the right questions, so the author tries to find out what has become indispensable for us, since when we have it, and who found it, and why, and what the consequences are for the present generation. The author mentions the persons, their biographies, and their achievements, showing that all knowledge and success was achieved by hard work. (orig./DG) [de

  13. 多倍化是杂草起源与演化的驱动力%Polyploidization, one of the driving forces for weed origin and evolution

    Institute of Scientific and Technical Information of China (English)

    李君; 强胜

    2012-01-01

    杂草及外来植物入侵给全球经济发展及生态环境都带来了严重危害,研究其起源与演化将有助于它们的管理与控制.多倍化是植物进化的主要驱动力量,然而多倍化在杂草起源与演化中的作用还停留在种类统计以及零碎的研究案例证据上.本文综述了植物多倍体基因组结构及基因表达的研究进展以及染色体加倍后的生态学效应.多倍化促进了基因组水平与表型水平的进化,影响物种或群体生存竞争能力和繁殖扩展能力,提高物种或群体生态适应性.这一遗传过程可能促使外来种在新的生境中的成功入侵进而转变为杂草,并提出重视开展对杂草及外来入侵植物的多倍化研究的设想.%Weeds and alien invasive plants have caused tremendously ecological and socio-economic damages and loses worldwide, therefore,it is important to study origin and evolution of weeds for their effective management. Polyploidy is believed to be the main driving force of plant evolution, however, its playing the role in weeds origin and evolution is poorly understood. In this paper we review the progresses on the polyploid genome structure and gene expression and the ecological consequences of chromosome doubling. The polyploidy promotes the evolution of genomic and phenotype, affects the species survival competition, reproduction and expansion capability, and improves the ecological adaptability. Polyploidization can drive the successful invasion of invasive alien species and consequently evolution into a weed in new habitats. In addition, it is proposed that the research works on invasive alien plants may focus on polyploidization function in weed evolution and alien plant invasion.

  14. Revealing the Driving Forces of Mid-Cities Urban Growth Patterns Using Spatial Modeling: a Case Study of Los Ángeles, Chile

    Directory of Open Access Journals (Sweden)

    Mauricio I. Aguayo

    2007-06-01

    Full Text Available City growth and changes in land-use patterns cause various important social and environmental impacts. To understand the spatial and temporal dynamics of these processes, the factors that drive urban development must be identified and analyzed, especially those factors that can be used to predict future changes and their potential environmental effects. Our objectives were to quantify the relationship between urban growth and its driving forces and to predict the spatial growth pattern based on historical land-use changes for the city of Los Ángeles in central Chile. This involved the analysis of images from 1978, 1992, and 1998 and characterization of the spatial pattern of land-use change; the construction of digital coverage in GIS; the selection of predictive variables through univariate analysis; the construction of logistic regression models using growth vs. nongrowth for 1978-1992 as the dependent variable; and the prediction of the probability of land-use change by applying the regression model to the 1992-1998 period. To investigate the influence of spatial scale, we constructed several sets of models that contained (1 only distance variables, e.g., distance to highways; (2 only scale-dependent density variables, e.g., density of urban area within a 600-m radius; (3 both distance and density variables; and (4 both distance and density variables at several spatial scales. The environmental variables were included in all models. The combination of distance and density variables at several scales is required to appropriately capture the multiscale urban growth process. The best models correctly predict ~90% of the observed land-use changes for 1992-1998. The distance to access roads, densities of the urban road system and urbanized area at various scales, and soil type were the strongest predictors of the growth pattern. Other variables were less important or not significant in explaining the urban growth process. Our approach, which

  15. Assessing driving forces of land use and land cover change by a mixed-method approach in north-eastern Ghana, West Africa.

    Science.gov (United States)

    Kleemann, Janina; Baysal, Gülendam; Bulley, Henry N N; Fürst, Christine

    2017-07-01

    Land use and land cover change (LULCC) is the result of complex human-environmental interactions. The high interdependencies in social-ecological systems make it difficult to identify the main drivers. However, knowledge of key drivers of LULCC, including indirect (underlying) drivers which cannot be easily determined by spatial or economic analyses, is essential for land use planning and especially important in developing countries. We used a mixed-method approach in order to detect drivers of LULCC in the Upper East Region of northern Ghana by different qualitative and quantitative methods which were compared in a confidence level analysis. Viewpoints from experts help to answer why the land use is changing, since many triggering effects, especially non-spatial and indirect drivers of LULCC, are not measurable by other methodological approaches. Geo-statistical or economic analyses add to validate the relevance of the expert-based results. First, we conducted in-depth interviews and developed a list of 34 direct and indirect drivers of LULCC. Subsequently, a group of experts was asked in a questionnaire to select the most important drivers by using a Likert scale. This information was complemented by remote sensing analysis. Finally, the driver analysis was compared to information from literature. Based on these analyses there is a very high confidence that population growth, especially in rural areas, is a major driver of LULCC. Further, current farming practice, bush fires, livestock, the road network and climate variability were the main direct drivers while the financial capital of farmers and customary norms regarding land tenure were listed as important indirect drivers with high confidence. Many of these driving forces, such as labour shortage and migration, are furthermore interdependent. Governmental laws, credits, the service by extension officers, conservational agriculture and foreign agricultural medium-scale investments are currently not driving

  16. Drive Stands

    Data.gov (United States)

    Federal Laboratory Consortium — The Electrical Systems Laboratory (ESL)houses numerous electrically driven drive stands. A drive stand consists of an electric motor driving a gearbox and a mounting...

  17. Estímulos ao Desenvolvimento Tecnológico: Influência do Mercado Driving Forces for Technology Development: Market

    Directory of Open Access Journals (Sweden)

    José de A. Cid

    2002-01-01

    Full Text Available Hoje em dia não se discute mais a importância da Pesquisa e Desenvolvimento para a sobrevivência e longevidade de uma Empresa. Todo tipo de indústria sente o impacto do aumento da competição e da velocidade dos avanços tecnológicos. Entretanto, os recursos estão escassos, tanto para as despesas necessárias às atividades de negócio quanto para a pesquisa, o que deixa os gerentes com a difícil tarefa de decidir onde os recursos serão aplicados. Anos atrás, quando os recursos eram (aparentemente ilimitados a força que impulsionava a pesquisa era o desafio da descoberta do novo. A complexidade do processo, os intricados métodos de análise, a quebra de barreiras do conhecimento, alimentavam as mentes dos cientistas. Depois da pesquisa, os profissionais de marketing deveriam encontrar mercados para os novos produtos. Atualmente a pesquisa de mercado, as ferramentas de análise de negócio e outros aspectos outrora desconhecidos dos cientistas dominam as mesas dos gerentes. Este artigo descreve três diferentes abordagens na distribuição de recursos para pesquisa e resume alguns dos princípios que ajudam as empresas a funcionar melhor.Nowadays the importance of Research and Development to a Company survival and longevity is well known. Virtually every industry feels the impact of increased competition and the fast pace of technology change. However, resources are getting scarce, both for doing business and research as well, leaving managers with the tough job of selecting which project will get funding. Years ago, when money was (seemingly unlimited the driving force to research was the challenge of inventing something new. The process complexity, the intricate analysis methods, the breaking of new frontiers were the food for the scientists inquiring minds. Then marketing professionals had to work to find or create market. Now market research, business analysis tools and other aspects once unknown to scientists rule. This article

  18. Study on HCl Driving Force for the Reaction of NaCl-Maleic Acid Mixing Single Droplet Using Micro-FTIR Spectroscopy

    Science.gov (United States)

    He, Xiang; Zhang, Yunhong

    2016-04-01

    Chemical aging is the one of the most important physicochemical process in atmospheric aerosols. Mixing of sea salt and water-soluble organic components has profound effects on the volatile characteristic and evolving chemical composition of the anthropogenic origin aerosols, which are poorly understood. In this study, the chemical reaction behavior of the mixture of NaCl and maleic acid (H2MA) micron-level single droplet was investigated using a gas-flow system combined with microscopic Fourier transform infrared (micro-FTIR) spectrometer over the range of relative humidity (63˜95% RH) for the first time. The results showed that the mixture of NaCl and H2MA single droplet could react to form monosodium maleate salt (NaHMA) at the constant RH from the characterization of the FTIR. The reaction is a result of an acid displacement reaction R1, which is driven by high volatility of the HCl product. NaCl(aq)+H2MA(aq)=NaHMA(aq)+HCl(aq,g) (R1) According to the change tendency of the absorbance values of 1579 cm-1 COO- stretching band of the NaHMA dependent upon reaction times at different RHs, the growth range of the trend which could lead to the faster reaction rate was obvious at lower RH. The water content of the droplet was also more likely to reduce rapidly with the loss of the RH from the absorbance changes of 3400 cm-1H2O stretching band dependent upon reaction times. These may be due to irreversible evaporation of HCl gas which is the main driving force for this type of reaction and the NaHMA is a less hygroscopic component compared to H2MA. And the HCl gas is more likely to evaporate faster from the single droplet and promote the reaction rate and the consumption of water content at lower RH. These results could help in understanding the chemical conversion processes of water-soluble dicarboxylic acids to dicarboxylate salts, as well as the consumption of Cl in sea salt aerosols by organic acids in the atmosphere.

  19. Dementia & Driving

    Science.gov (United States)

    ... have to give up driving. Many people associate driving with self-reliance and freedom; the loss of driving privileges ... familiar roads and avoid long distances. Avoid heavy traffic and heavily traveled roads. Avoid driving at night and in bad weather. Reduce the ...

  20. A high force of plasmodium vivax blood-stage infection drives the rapid acquisition of immunity in papua new guinean children.

    Directory of Open Access Journals (Sweden)

    Cristian Koepfli

    Full Text Available When both parasite species are co-endemic, Plasmodium vivax incidence peaks in younger children compared to P. falciparum. To identify differences in the number of blood stage infections of these species and its potential link to acquisition of immunity, we have estimated the molecular force of blood-stage infection of P. vivax ((molFOB, i.e. the number of genetically distinct blood-stage infections over time, and compared it to previously reported values for P. falciparum.P. vivax (molFOB was estimated by high resolution genotyping parasites in samples collected over 16 months in a cohort of 264 Papua New Guinean children living in an area highly endemic for P. falciparum and P. vivax. In this cohort, P. vivax episodes decreased three-fold over the age range of 1-4.5 years.On average, children acquired 14.0 new P. vivax blood-stage clones/child/year-at-risk. While the incidence of clinical P. vivax illness was strongly associated with mol FOB (incidence rate ratio (IRR = 1.99, 95% confidence interval (CI95 [1.80, 2.19], (molFOB did not change with age. The incidence of P. vivax showed a faster decrease with age in children with high (IRR = 0.49, CI95 [0.38, 0.64] p<0.001 compared to those with low exposure (IRR = 0.63, CI95[0.43, 0.93] p = 0.02.P. vivax (molFOB is considerably higher than P. falciparum (molFOB (5.5 clones/child/year-at-risk. The high number of P. vivax clones that infect children in early childhood contribute to the rapid acquisition of immunity against clinical P. vivax malaria.

  1. STRONG POINTS AND INTERNAL AND EXTERNAL VULNERABILITIES OF THE MILITARY COMMUNICATIONS AND INFORMATICS SYSTEMS AND NETWORKS DEVELOPED IN THE ROMANIAN ARMED FORCES UNDER THE CIRCUMSTANCES OF THE CURRENT SECURITY CHALLENGES

    Directory of Open Access Journals (Sweden)

    Constantin MINCU

    2015-12-01

    Full Text Available The author briefly presents a series of recent aspects in the current geopolitical context regarding some strong points as well as internal and external vulnerabilities of the military communication and informatics systems and networks developed in the Romanian Armed Forces since 1997. In the second section we referred to the evolutions in austerity and hostility conditions of the main operational and technical sequels of Romanian Armed Forces Transmissions System - STAR (RTP/RMNC. Furthermore, we presented some strong points of the achieved systems and principles taken into account along the modernization and transformation effort (regarding the NATO criteria and requirements, as well as their internal and external vulnerabilities identified following a thorough analysis.

  2. Effects of physical forcing on COastal ZOoplankton community structure: study of the unusual case of a MEDiterranean ecosystem under strong tidal influence (Project COZOMED-MERMEX)

    Science.gov (United States)

    Pagano, Marc

    2017-04-01

    Groupe COZOMED: R. Arfi (1), A. Atoui (2), H. Ayadi (6), B. Bejaoui (1), N. Bhairy (1), N. Barraj (2), M. Belhassen (2), S. Benismail (2), M.Y Benkacem (2), J. Blanchot (1), M. Cankovic(5), F. Carlotti (1), C. Chevalier (1), I Ciglenecki-Jusic (5), D. Couet (1), N. Daly Yahia (3), L. Dammak (2), J.-L. Devenon (1), Z. Drira (6), A. Hamza (2), S. Kmia (6), N. Makhlouf (3), M. Mahfoudi (2), M. Moncef (4), M. Pagano (1), C. Sammari (2), H. Smeti (2), A. Zouari (2) The COZOMED-MERMEX project aims at understanding how hydrodynamic forcing (currents, tides, winds) combine with anthropogenic forcing and climate to affect the variability of coastal Mediterranean zooplankton communities under contrasting tidal influence. This study includes (i) a zero state of knowledge via a literature review of existing data and (ii) a case study on the system Boughrara lagoon - Gulf of Gabes. This ecosystem gives major services for Tunisia (about 65% of national fish production) but is weakened by its situation in a heavily anthropized area and under influence of urban, industrial and agricultural inputs. Besides this region is subject to specific climate forcing (Sahelian winds, scorching heat, intense evaporation, flooding) which possible changes will be considered. The expected issues are (i) to improve our knowledge of hydrodynamic forcing on zooplankton and ultimately on the functioning of coastal Mediterranean ecosystems impacted by anthropogenic and climatic effects and (ii) to elaborate management tools to help preserving good ecological status of these ecosystems: hydrodynamic circulation model, mapping of isochrones of residence times, mapping of the areas of highest zooplankton abundances (swarms), and sensitive areas, etc. This project strengthens existing scientific collaborations within the MERMEX program (The MerMex Group, 2011) and in the frame of an international joint laboratory (COSYS-Med) created in 2014. A first field mulidisciplinary campaign was performed in October

  3. Distracted driving

    Science.gov (United States)

    ... including maps) The Dangers of Talking on the Phone While Driving You are four times more likely to get ... of reach. If you are caught using a phone while driving, you may risk a ticket or fine. Most ...

  4. Distracted Driving

    Science.gov (United States)

    ... and increased awareness of distracted driving using radio advertisements, news stories, and similar media. After the projects ... available at www.trafficsafetymarketing.gov . Distracted Driving Enforcement – TV Ads (Paid). For re-tagging, go to: www. ...

  5. [Innovation drive is the original motive force of discipline construction: the developing road of Department of Burns and Plastic Surgery in the 309th Hospital of PLA].

    Science.gov (United States)

    Jia, C Y

    2018-03-20

    Discipline construction is a systematic project, covering clinic, teaching, scientific research, management, and humanity. Based on the perspective of innovation drive, from the aspects of discipline structure setting, specialized laboratory construction, sub-specialty formation, clinical characteristic and advantage formation, and management concept update, this article summarizes the growth process of Department of Burns and Plastic Surgery in the 309th Hospital of PLA.

  6. [Driving forces of carbon emission from energy consumption in China old industrial cities: a case study of Shenyang City, Northeast China].

    Science.gov (United States)

    Ren, Wan-Xia; Geng, Yong; Xue, Bing

    2012-10-01

    To quantitatively analyze the effects of anthropogenic factors on regional environmental quality is a hot topic in the field of sustainable development research. Taking the typical old industrial city Shenyang in Northeast China as a case, and by using the IPCC method for calculating carbon emission from energy consumption, this paper estimated the carbon emission from energy consumption in the city in 1978-2009, and a time series analysis on the anthropogenic factors driving this carbon emission was made by the STIRPAT model based upon Kaya equation and ridge regression. In 1978-2009, the carbon emission in the city had a slow increase first, slow decrease then, and a rapid increase thereafter. The total carbon emission in 2009 was 4.6 times of that in 1978. Population growth was the main factor driving the growth of the emission, and there existed an equal-proportional variation between the population growth and the carbon emission growth. Urbanization was another main driving factor followed by population growth, and the per capita GDP was positively correlated with the carbon emission. Kuznets curve did not exist for the relationship between economic development and carbon emission in Shenyang. Energy source intensity reduction (representing technology improvement) was the main factor driving the reduction of the total carbon emission.

  7. Voluntary drive-dependent changes in vastus lateralis motor unit firing rates during a sustained isometric contraction at 50% of maximum knee extension force.

    NARCIS (Netherlands)

    de Ruiter, C.J.; Elzinga, M.J.; Verdijk, PW; van Mechelen, W.; de Haan, A.

    2004-01-01

    The purpose of the present study was to relate the expected inter-subject variability in voluntary drive of the knee extensor muscles during a sustained isometric contraction to the changes in firing rates of single motor units. Voluntary activation, as established with super-imposed electrical

  8. Electric drives

    CERN Document Server

    Boldea, Ion

    2005-01-01

    ENERGY CONVERSION IN ELECTRIC DRIVESElectric Drives: A DefinitionApplication Range of Electric DrivesEnergy Savings Pay Off RapidlyGlobal Energy Savings Through PEC DrivesMotor/Mechanical Load MatchMotion/Time Profile MatchLoad Dynamics and StabilityMultiquadrant OperationPerformance IndexesProblemsELECTRIC MOTORS FOR DRIVESElectric Drives: A Typical ConfigurationElectric Motors for DrivesDC Brush MotorsConventional AC MotorsPower Electronic Converter Dependent MotorsEnergy Conversion in Electric Motors/GeneratorsPOWER ELECTRONIC CONVERTERS (PECs) FOR DRIVESPower Electronic Switches (PESs)The

  9. Application of face centred central composite design to optimise compression force and tablet diameter for the formulation of mechanically strong and fast disintegrating orodispersible tablets.

    Science.gov (United States)

    Pabari, Ritesh M; Ramtoola, Zebunnissa

    2012-07-01

    A two factor, three level (3(2)) face centred, central composite design (CCD) was applied to investigate the main and interaction effects of tablet diameter and compression force (CF) on hardness, disintegration time (DT) and porosity of mannitol based orodispersible tablets (ODTs). Tablet diameters of 10, 13 and 15 mm, and CF of 10, 15 and 20 kN were studied. Results of multiple linear regression analysis show that both the tablet diameter and CF influence tablet characteristics. A negative value of regression coefficient for tablet diameter showed an inverse relationship with hardness and DT. A positive value of regression coefficient for CF indicated an increase in hardness and DT with increasing CF as a result of the decrease in tablet porosity. Interestingly, at the larger tablet diameter of 15 mm, while hardness increased and porosity decreased with an increase in CF, the DT was resistant to change. The optimised combination was a tablet of 15 mm diameter compressed at 15 kN showing a rapid DT of 37.7s and high hardness of 71.4N. Using these parameters, ODTs containing ibuprofen showed no significant change in DT (ANOVA; p>0.05) irrespective of the hydrophobicity of the ibuprofen. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Characterizing Spatiotemporal Pattern of Land Use Change and Its Driving Force Based on GIS and Landscape Analysis Techniques in Tianjin during 2000–2015

    Directory of Open Access Journals (Sweden)

    Yafei Li

    2017-05-01

    Full Text Available The spatial and temporal characteristics and driving factors analysis of regional land use are the core scientific problems in the research of ecological environment and human sustainable development. It is also an important basis for the government to formulate land management policy. Based on the land use maps of 2000, 2005, 2010 and 2015, this article analyzed the spatiotemporal pattern of land use change in Tianjin, and determined the relative importance of each driving factor of land use change. The main features of land use change were the continuous expansion of built-up land (1386.89 km2/74.73% gains and the decrease of arable land area (1181.60 km2/16.84% losses. The area and intensity of land use change were not completely consistent, such as Wuqing and Jixian. The hotspots of land use change mainly were located in the main urban region in Tianjin, around the suburban settlements and Binhai New Area. The landscape pattern in the research region has also changed significantly. The Largest patch index (LPI and largest shape index (LSI of arable land showed an increasing trend, and the degree of landscape fragmentation of arable land was deepened. The trend of landscape index of built-up land was similar to that of arable land, but the change intensity was more severe. In addition, the article also used the stepwise regression analysis in the multiple regression to analyze the relative importance of various driving factors, indicating that the driving factors of the built-up land and arable land change were obviously different in different periods. Government policies also have a significant impact on land use change, such as establishing the Tianjin Binhai New Area (TBNA.

  11. Multiregional Input-Output Analysis of Spatial-Temporal Evolution Driving Force for Carbon Emissions Embodied in Interprovincial Trade and Optimization Policies: Case Study of Northeast Industrial District in China.

    Science.gov (United States)

    Cheng, Hao; Dong, Suocheng; Li, Fujia; Yang, Yang; Li, Shantong; Li, Yu

    2018-01-02

    In the counties with rapid economy and carbon emissions (CEs) growth, CEs embodied in interprovincial trade (CEs-PT) significantly impacts the CEs amount and structure and represents a key issue to consider in CEs reduction policies formulation. This study applied EEBT and two-stage SDA model to analyze the characteristics and driving force of spatial-temporal evolution for net CEs-PT outflow in the Northeast Industrial District of China (NID). We found that, during 1997-2007, the net CEs-PT flowed out from NID to 16 south and east provinces, then to 23 provinces all over China, and its amount has increased 216.798Mt (by 211.67% per year). The main driving forces are technology and demand (further decomposed into structure and scale matrix); the contribution are 71.6418 Mt and 145.1562 Mt. Then, we constructed coupling relationship model and took the top three industries with the greatest net CEs-PT outflow (farming, forestry, animal husbandry and fisheries, electricity and heat production and supply, petroleum processing, coking, and nuclear fuel processing) as examples, adjusted the interprovincial trade constructions, scales, and objects, to reduce the CEs-PT with lower costs, greater effect, and more equitability. The achievement could provide reference for formulating CEs reduction policies for similar areas in the world characterized by rapid growth of economy and CEs.

  12. Pile Driving

    Science.gov (United States)

    1987-01-01

    Machine-oriented structural engineering firm TERA, Inc. is engaged in a project to evaluate the reliability of offshore pile driving prediction methods to eventually predict the best pile driving technique for each new offshore oil platform. Phase I Pile driving records of 48 offshore platforms including such information as blow counts, soil composition and pertinent construction details were digitized. In Phase II, pile driving records were statistically compared with current methods of prediction. Result was development of modular software, the CRIPS80 Software Design Analyzer System, that companies can use to evaluate other prediction procedures or other data bases.

  13. A new force emerges from the dark side: evidence is growing that an intrinsic property of the universe is helping to drive its expansion

    CERN Multimedia

    Cookson, C

    2003-01-01

    "Astronomical surveys over the past five years have forced cosmologists to conclude that ordinary matter - in the form of familiar stars, planets and interstellar dust or more exotic objects, such as quasars and neutron stars - makes up only 4 per cent of the universe" (1 page).

  14. <strong>Mini-project>

    DEFF Research Database (Denmark)

    Katajainen, Jyrki

    2008-01-01

    In this project the goal is to develop the safe * family of containers for the CPH STL. The containers to be developed should be safer and more reliable than any of the existing implementations. A special focus should be put on strong exception safety since none of the existing prototypes available...

  15. Vortex dynamics in type-II superconductors under strong pinning conditions

    Science.gov (United States)

    Thomann, A. U.; Geshkenbein, V. B.; Blatter, G.

    2017-10-01

    We study effects of pinning on the dynamics of a vortex lattice in a type-II superconductor in the strong-pinning situation and determine the force-velocity (or current-voltage) characteristic combining analytical and numerical methods. Our analysis deals with a small density np of defects that act with a large force fp on the vortices, thereby inducing bistable configurations that are a characteristic feature of strong pinning theory. We determine the velocity-dependent average pinning-force density 〈Fp(v ) 〉 and find that it changes on the velocity scale vp˜fp/η a03 , where η is the viscosity of vortex motion and a0 the distance between vortices. In the small pin-density limit, this velocity is much larger than the typical flow velocity vc˜Fc/η of the free vortex system at drives near the critical force density Fc=〈Fp(v =0 ) 〉 ∝npfp . As a result, we find a generic excess-force characteristic, a nearly linear force-velocity characteristic shifted by the critical force density Fc; the linear flux-flow regime is approached only at large drives. Our analysis provides a derivation of Coulomb's law of dry friction for the case of strong vortex pinning.

  16. Control rod drive

    International Nuclear Information System (INIS)

    Hawke, B.C.

    1986-01-01

    A reactor core, one or more control rods, and a control rod drive are described for selectively inserting and withdrawing the one or more control rods into and from the reactor core, which consists of: a support structure secured beneath the reactor core; control rod positioning means supported by the support structure for movably supporting the control rod for movement between a lower position wherein the control rod is located substantially beneath the reactor core and an upper position wherein at least an upper portion of the control rod extends into the reactor core; transmission means; primary drive means connected with the control rod positioning means by the transmission means for positioning the control rod under normal operating conditions; emergency drive means for moving the control rod from the lower position to the upper position under emergency conditions, the emergency drive means including a weight movable between an upper and a lower position, means for movably supporting the weight, and means for transmitting gravitational force exerted on the weight to the control rod positioning means to move the control rod upwardly when the weight is pulled downwardly by gravity; the transmission means connecting the control rod positioning means with the emergency drive means so that the primary drive means effects movement of the weight and the control rod in opposite directions under normal conditions, thus providing counterbalancing to reduce the force required for upward movement of the control rod under normal conditions; and restraint means for restraining the fall of the weight under normal operating conditions and disengaging the primary drive means to release the weight under emergency conditions

  17. Impaired Driving

    Science.gov (United States)

    ... Get the Facts What Works: Strategies to Increase Car Seat and Booster Seat ... narcotics. 3 That’s one percent of the 111 million self-reported episodes of alcohol-impaired driving among U.S. ...

  18. Dual role of an ac driving force and the underlying two distinct order–disorder transitions in the vortex phase diagram of Ca3Ir4Sn13

    International Nuclear Information System (INIS)

    Kumar, Santosh; Singh, Ravi P.; Thamizhavel, A.; Tomy, C.V.; Grover, A.K.

    2014-01-01

    Highlights: • This work pertains to new findings related to a broad SMP anomaly. • Broad SMP prima facie encompasses two phase transformations in vortex matter. • We demarcated two phase boundaries pertaining to order–disorder transitions which have quasi first-order nature. - Abstract: We present distinct demarcation of the Bragg glass (BG) to multi-domain vortex glass (VG) transition line and the eventual amorphization of the VG phase in a weakly pinned single crystal of the superconducting compound Ca 3 Ir 4 Sn 13 on the basis of comprehension of the different yields about the second magnetization peak (SMP) anomaly in the dc magnetization and the corresponding anomalous feature in the ac susceptibility measurements. The shaking by a small ac magnetic field, inevitably present in the ac susceptibility measurements, is seen to result in contrasting responses in two different portions of the field-temperature (H, T) phase space of the multi-domain VG. In one of the portions, embracing the BG to VG transition across the onset of the SMP anomaly, the ac drive is surprisingly seen to assist the transformation of the well ordered BG phase to a lesser ordered VG phase. The BG phase exists as a superheated state over a small portion of the VG space and this attests to the first order nature of the BG to VG transition

  19. Activation of lysosomal P2X4 by ATP transported into lysosomes via VNUT/SLC17A9 using V‐ATPase generated voltage gradient as the driving force

    Science.gov (United States)

    Zhong, Xi Zoë; Cao, Qi; Sun, Xue

    2016-01-01

    Key points SLC17A9 proteins function as a lysosomal ATP transporter responsible for lysosomal ATP accumulation.P2X4 receptors act as lysosomal ion channels activated by luminal ATP.SLC17A9‐mediated ATP transport across the lysosomal membrane is suppressed by Bafilomycin A1, the V‐ATPase inhibitor.SLC17A9 mainly uses voltage gradient but not pH gradient generated by the V‐ATPase as the driving force to transport ATP into the lysosome to activate P2X4. Abstract The lysosome contains abundant ATP which plays important roles in lysosome functions and in cell signalling. Recently, solute carrier family 17 member 9 (SLC17A9, also known as VNUT for vesicular nucleotide transporter) proteins were suggested to function as a lysosomal ATP transporter responsible for lysosomal ATP accumulation, and P2X4 receptors were suggested to be lysosomal ion channels that are activated by luminal ATP. However, the molecular mechanism of SLC17A9 transporting ATP and the regulatory mechanism of lysosomal P2X4 are largely unknown. In this study, we report that SLC17A9‐mediated ATP transport across lysosomal membranes is suppressed by Bafilomycin A1, the V‐ATPase inhibitor. By measuring P2X4 activity, which is indicative of ATP transport across lysosomal membranes, we further demonstrated that SLC17A9 mainly uses voltage gradient but not pH gradient as the driving force to transport ATP into lysosomes. This study provides a molecular mechanism for lysosomal ATP transport mediated by SLC17A9. It also suggests a regulatory mechanism of lysosomal P2X4 by SLC17A9. PMID:27477609

  20. Current drive by Alfven waves in elongated cross section tokamak

    International Nuclear Information System (INIS)

    Tsypin, V.S.; Elfimov, A.G.; Nekrasov, F.M.; Azevedo, C.A.; Assis, A.S. de

    1997-01-01

    Full text. The problem of the noninductive current drive in cylindrical plasma model and in circular cross-section tokamaks had been already discussed intensively. At the beginning of the study of this problem it have been clear that there are significant difficulties in using of the current-drive in toroidal magnetic traps, especially in a tokamak reactor. Thus, in the case of the lower-hybrid current-drive the efficiency of this current-drive drops strongly as the plasma density increases. For the Alfven waves, there is an opinion that the efficiency of the current-drive drops as a result of waves absorption by the trapped particles 1,2. Okhawa proposed that the current in a magnetized plasma can be maintained also by means of forces, depending on the radiofrequency (rf) field amplitude gradients (the helicity injection). This idea was developed later, some new hopes appeared, connected with the possibility of the current-drive efficiency increasing. It was shown that for the cylindrical plasmas the local efficiency of Alfev wave current drive can be increased by one order of magnitude due to gradient forces, for the kinetic Alfven waves (KAW) and the global Alfven waves 9GAW) at some range of the phase velocity. For tokamaks, this additional nonresonant current drive does not depend on the trapped particle effects, which reduce strongly the Alfven current drive efficiency in tokamaks, as it is supposed. Now, the theory development of the Alfven wave (AW) current drive is very important in the cource of the future experiments on the TCA/BR tokamak (Brazil). In this paper, an attempt is made to clarify some general aspects of this problems for magnetic traps. For large aspects ratio tokamaks, with an elongated cross-section, some general formulas concerning the untrapped and trapped particles dynamics and their input to the Landau damping of the Alfven waves, are presented. They are supposed to be used for the further development of the Alfven current drive theory

  1. Current drive by Alfven waves in elongated cross section tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Tsypin, V.S.; Elfimov, A.G.; Nekrasov, F.M.; Azevedo, C.A. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Fisica; Assis, A.S. de [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Fisica

    1997-12-31

    Full text. The problem of the noninductive current drive in cylindrical plasma model and in circular cross-section tokamaks had been already discussed intensively. At the beginning of the study of this problem it have been clear that there are significant difficulties in using of the current-drive in toroidal magnetic traps, especially in a tokamak reactor. Thus, in the case of the lower-hybrid current-drive the efficiency of this current-drive drops strongly as the plasma density increases. For the Alfven waves, there is an opinion that the efficiency of the current-drive drops as a result of waves absorption by the trapped particles 1,2. Okhawa proposed that the current in a magnetized plasma can be maintained also by means of forces, depending on the radiofrequency (rf) field amplitude gradients (the helicity injection). This idea was developed later, some new hopes appeared, connected with the possibility of the current-drive efficiency increasing. It was shown that for the cylindrical plasmas the local efficiency of Alfev wave current drive can be increased by one order of magnitude due to gradient forces, for the kinetic Alfven waves (KAW) and the global Alfven waves (GAW) at some range of the phase velocity. For tokamaks, this additional nonresonant current drive does not depend on the trapped particle effects, which reduce strongly the Alfven current drive efficiency in tokamaks, as it is supposed. Now, the theory development of the Alfven wave (AW) current drive is very important in the cource of the future experiments on the TCA/BR tokamak (Brazil). In this paper, an attempt is made to clarify some general aspects of this problems for magnetic traps. For large aspects ratio tokamaks, with an elongated cross-section, some general formulas concerning the untrapped and trapped particles dynamics and their input to the Landau damping of the Alfven waves, are presented. They are supposed to be used for the further development of the Alfven current drive theory

  2. Heavy metal(loid)s and organic contaminants in groundwater in the Pearl River Delta that has undergone three decades of urbanization and industrialization: Distributions, sources, and driving forces.

    Science.gov (United States)

    Huang, Guanxing; Zhang, Ming; Liu, Chunyan; Li, Liangping; Chen, Zongyu

    2018-09-01

    Urbanization and industrialization have increased groundwater resource demands, and may drive the change of heavy metal(loid)s and organic chemicals in groundwater in the Pearl River Delta (PRD), southern China. Thus, a comprehensive understanding of the distributions, sources, and driving forces of heavy metal(loid)s and organic chemicals in groundwater in the PRD is vital for water resource management in this region. In this study, eight heavy metal(loid)s and fifty-five organic chemicals in groundwater across the PRD were investigated. The results show that undrinkable groundwater related to heavy metal(loid)s was mainly due to high concentrations of Fe (19.3%) and As (6.8%). Eighteen organic contaminants were detected in groundwater in the PRD, where the most frequently detected organic contaminant was naphthalene, and its detection rate was 2.51%. In 5.3% of all groundwater samples, one or more organic contaminants were found. All detected organic contaminants, except ones without allowable limits, in groundwater were at concentrations below allowable limits of China. The mean concentrations of heavy metal(loid)s in granular aquifers were higher than those in fissured and karst aquifers, especially for Fe and As. Except Se, the mean concentrations of other heavy metal(loid)s and the frequency of detection of organic contaminants in groundwater in urbanized and peri-urban areas were higher than those in non-urbanized areas, especially for Hg, Co, and organic contaminants. Fe, As, and Se in groundwater mainly originated from the release of Fe/As/Se rich sediments. The former two were driven by reduction reactions, while the latter was driven by oxidation resulting from the infiltration of NO 3 - . In contrast, other five heavy metal(loid)s and organic contaminants in groundwater mainly originated from the anthropogenic sources, such as the infiltration of industrial sewage. It is evident that urbanization and industrialization are two powerful driving forces for

  3. Vegetation dynamics and its driving forces from climate change and human activities in the Three-River Source Region, China from 1982 to 2012

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ying; Zhang, Chaobin; Wang, Zhaoqi; Chen, Yizhao; Gang, Chengcheng [School of Life Science, Nanjing University, Xianlin Road 163, Qixia District, Nanjing, 210046 (China); An, Ru [School of Earth Science and Engineering, Hohai University, Xikang Road 129, Nanjing, 210098 (China); Li, Jianlong, E-mail: lijianlongnju@163.com [School of Life Science, Nanjing University, Xianlin Road 163, Qixia District, Nanjing, 210046 (China)

    2016-09-01

    The Three-River Source Region (TRSR), a region with key importance to the ecological security of China, has undergone climate changes and a shift in human activities driven by a series of ecological restoration projects in recent decades. To reveal the spatiotemporal dynamics of vegetation dynamics and calculate the contributions of driving factors in the TRSR across different periods from 1982 to 2012, net primary productivity (NPP) estimated using the Carnegie–Ames–Stanford approach model was used to assess the status of vegetation. The actual effects of different climatic variation trends on interannual variation in NPP were analyzed. Furthermore, the relationships of NPP with different climate factors and human activities were analyzed quantitatively. Results showed the following: from 1982 to 2012, the average NPP in the study area was 187.37 g cm{sup −2} yr{sup −1}. The average NPP exhibited a fluctuation but presented a generally increasing trend over the 31-year study period, with an increase rate of 1.31 g cm{sup −2} yr{sup −2}. During the entire study period, the average contributions of temperature, precipitation, and solar radiation to NPP interannual variation over the entire region were 0.58, 0.73, and 0.09 g cm{sup −2} yr{sup −2}, respectively. Radiation was the climate factor with the greatest influence on NPP interannual variation. The factor that restricted NPP increase changed from temperature and radiation to precipitation. The average contributions of climate change and human activities to NPP interannual variation were 1.40 g cm{sup −2} yr{sup −2} and − 0.08 g cm{sup −2} yr{sup −2}, respectively. From 1982 to 2000, the general climate conditions were favorable to vegetation recovery, whereas human activities had a weaker negative impact on vegetation growth. From 2001 to 2012, climate conditions began to have a negative impact on vegetation growth, whereas human activities made a favorable impact on vegetation

  4. Vegetation dynamics and its driving forces from climate change and human activities in the Three-River Source Region, China from 1982 to 2012

    International Nuclear Information System (INIS)

    Zhang, Ying; Zhang, Chaobin; Wang, Zhaoqi; Chen, Yizhao; Gang, Chengcheng; An, Ru; Li, Jianlong

    2016-01-01

    The Three-River Source Region (TRSR), a region with key importance to the ecological security of China, has undergone climate changes and a shift in human activities driven by a series of ecological restoration projects in recent decades. To reveal the spatiotemporal dynamics of vegetation dynamics and calculate the contributions of driving factors in the TRSR across different periods from 1982 to 2012, net primary productivity (NPP) estimated using the Carnegie–Ames–Stanford approach model was used to assess the status of vegetation. The actual effects of different climatic variation trends on interannual variation in NPP were analyzed. Furthermore, the relationships of NPP with different climate factors and human activities were analyzed quantitatively. Results showed the following: from 1982 to 2012, the average NPP in the study area was 187.37 g cm"−"2 yr"−"1. The average NPP exhibited a fluctuation but presented a generally increasing trend over the 31-year study period, with an increase rate of 1.31 g cm"−"2 yr"−"2. During the entire study period, the average contributions of temperature, precipitation, and solar radiation to NPP interannual variation over the entire region were 0.58, 0.73, and 0.09 g cm"−"2 yr"−"2, respectively. Radiation was the climate factor with the greatest influence on NPP interannual variation. The factor that restricted NPP increase changed from temperature and radiation to precipitation. The average contributions of climate change and human activities to NPP interannual variation were 1.40 g cm"−"2 yr"−"2 and − 0.08 g cm"−"2 yr"−"2, respectively. From 1982 to 2000, the general climate conditions were favorable to vegetation recovery, whereas human activities had a weaker negative impact on vegetation growth. From 2001 to 2012, climate conditions began to have a negative impact on vegetation growth, whereas human activities made a favorable impact on vegetation recovery. - Highlights: • Partitioned the

  5. Driving things

    DEFF Research Database (Denmark)

    Nevile, Maurice Richard

    2015-01-01

    I explore how participants organise involvement with objects brought into the car, relative to the demands of driving and social activity. Objects in cars commonly include phones or other technologies, food, body care products, texts, clothing, bags and carry items, toys, and even animals...... 2004, Haddington et al. 2012). I focus here especially on how the practical and interactional work of locating, seeing, placing, handling, hearing, and relinquishing, is ordered and accomplished relative to the emerging and contingent demands of both driving and social participation......, such that involvement with objects is constituted as secondary to driving in a multiactivity setting (e.g. Haddington et al. 2014). We see how events with, for, of, and even by objects can occur as predictable, planned and even designed for (e.g. changing glasses, applying body lotion), or might be unexpected...

  6. A Strong Fighting Force Is a Diverse Fighting Force

    Science.gov (United States)

    2015-01-01

    barrier or glass ceiling that precluded someone like me from achieving that level of rank and responsibility. Some may feel there is no point in pursuing...grade of major general, and none of those were women or people of color. Do not get me wrong—at that point in my career I was not thinking about

  7. Water mass interaction in the confluence zone of the Daning River and the Yangtze River--a driving force for algal growth in the Three Gorges Reservoir.

    Science.gov (United States)

    Holbach, Andreas; Wang, Lijing; Chen, Hao; Hu, Wei; Schleicher, Nina; Zheng, Binghui; Norra, Stefan

    2013-10-01

    Increasing eutrophication and algal bloom events in the Yangtze River Three Gorges Reservoir, China, are widely discussed with regard to changed hydrodynamics and nutrient transport and distribution processes. Insights into water exchange and interaction processes between water masses related to large-scale water level fluctuations in the reservoir are crucial to understand water quality and eutrophication dynamics. Therefore, confluence zones of tributaries with the Yangtze River main stream are dedicated key interfaces. In this study, water quality data were recorded in situ and on-line in varying depths with the MINIBAT towed underwater multi-sensor system in the confluence zone of the Daning River and the Yangtze River close to Wushan City during 1 week in August 2011. Geostatistical evaluation of the water quality data was performed, and results were compared to phosphorus contents of selective water samples. The strongly rising water level throughout the measurement period caused Yangtze River water masses to flow upstream into the tributary and supply their higher nutrient and particulate loads into the tributary water body. Rapid algal growth and sedimentation occurred immediately when hydrodynamic conditions in the confluence zone became more serene again. Consequently, water from the Yangtze River main stream can play a key role in providing nutrients to the algal bloom stricken water bodies of its tributaries.

  8. Control rod drive mechanism

    International Nuclear Information System (INIS)

    Mizuno, Katsuyuki.

    1976-01-01

    Object: To restrict the reduction in performance due to stress corrosion cracks by making use of condensate produced in a turbine steam condenser. Structure: Water produced in a turbine steam condenser is forced into a condensed water desalting unit by low pressure condensate pump. The condensate is purified and then forced by a high pressure condensate pump into a feedwater heater for heating before it is returned to the reactor by a feedwater pump. Part of the condensate issuing from the condensate desalting unit is branched from the remaining portion at a point upstream the pump and is withdrawn into a control rod drive water pump after passing through a motordriven bypass valve, an orifice and a condenser water level control valve, is pressurized in the control rod drive water desalting unit and supplied to a control rod drive water pressure system. The control rod is vertically moved by the valve operation of the water pressure system. Since water of high oxygen concentration does not enter during normal operation, it is possible to prevent the stress cracking of the stainless steel apparatus. (Nakamura, S.)

  9. Control rod drive

    International Nuclear Information System (INIS)

    Watando, Kosaku; Tanaka, Yuzo; Mizumura, Yasuhiro; Hosono, Kazuya.

    1975-01-01

    Object: To provide a simple and compact construction of an apparatus for driving a drive shaft inside with a magnetic force from the outside of the primary system water side. Structure: The weight of a plunger provided with an attraction plate is supported by a plunger lift spring means so as to provide a buffer action at the time of momentary movement while also permitting the load on lift coil to be constituted solely by the load on the drive shaft. In addition, by arranging the attraction plate and lift coil so that they face each other with a small gap there-between, it is made possible to reduce the size and permit efficient utilization of the attracting force. Because of the small size, cooling can be simply carried out. Further, since there is no mechanical penetration portion, there is no possibility of leakage of the primary system water. Furthermore, concentration of load on a latch pin is prevented by arranging so that with a structure the load of the control rod to be directly beared through the scrum latch. (Kamimura, M.)

  10. [Study on the types and water pollution driving forces of the typical and medium-small-sized cities in the southern China based on the analysis of water environment].

    Science.gov (United States)

    Jiao, Shi-Xing; Wang, La-Chun; Huo, Yu; Chen, Chang-Chun; Teng, Juan

    2009-07-15

    According to the major pollution sources of urban water environment, 10 indexes such as industrial sewage quantity were closen to establish evaluation indexes system about the types and influencing factors of the typical and medium-small-sized cities in the southern China. Case studies of 16 typical and medium-small-sized cities were taken in Jiangsu, Zhejiang, Hubei and Anhui provinces. Combined with SPSS 11.0 cluster analysis results, city types were divided in reference to the values of water resources comprehensive pollution indexes and economical development indexes. The driving forces about city water environment pollution were studied by principal component analysis method. The result indicates that the 16 cities belong to two categories and four sub-categories, which are rich economy as well as light pollution of water environment and poor economy as well as heavy pollution of water environment. The influencing factors of water environment pollution are in sequence of industrial water pollution, agricultural no-point source pollution and urban domestic water pollution. The main factors of water environment pollution influenced I category cities, II as well as IV category cities and III category cities are industrial water pollution, urban domestic pollution and agricultural no-point source pollution respectively.

  11. An Improved Car-Following Model Accounting for Impact of Strong Wind

    Directory of Open Access Journals (Sweden)

    Dawei Liu

    2017-01-01

    Full Text Available In order to investigate the effect of strong wind on dynamic characteristic of traffic flow, an improved car-following model based on the full velocity difference model is developed in this paper. Wind force is introduced as the influence factor of car-following behavior. Among three components of wind force, lift force and side force are taken into account. The linear stability analysis is carried out and the stability condition of the newly developed model is derived. Numerical analysis is made to explore the effect of strong wind on spatial-time evolution of a small perturbation. The results show that the strong wind can significantly affect the stability of traffic flow. Driving safety in strong wind is also studied by comparing the lateral force under different wind speeds with the side friction of vehicles. Finally, the fuel consumption of vehicle in strong wind condition is explored and the results show that the fuel consumption decreased with the increase of wind speed.

  12. Electric drives

    Energy Technology Data Exchange (ETDEWEB)

    1986-10-01

    Several electric vehicles have been tested in long-term tests, i.e. an electric passenger car (maximum speed 115 km/h) and several busses for use in pedestrians' zones, spas, airports, natural reserves, and urban transportation (DUO busses). The ICE high-speed train is discussed in some detail, i.e. its aeroacoustic and aerodynamic design, running gear, computer-controlled drives and brakes, diagnostic systems, and electrical equipment. The Berlin Maglev system is mentioned as well as current inverters in rail vehicles. (HWJ).

  13. The community as a driving force.

    Science.gov (United States)

    1993-12-01

    A Workshop on Effective Strategies for Sustainable Community-based Family Planning (FP) and Maternal and Child Health (MCH) was held on October 14-23, 1993, as part of an Asian regional project focusing on women. Bangladesh, China, Laos, Nepal, the Philippines, and Viet Nam were represented at the workshop. The program introduced participants to effective community participation strategies in FP and MCH in Indonesia and allowed for the exchange of information. The UN Population Fund expressed support and encouragement for the exchange and recognition of Indonesia's government support for efforts at regional exchanges. Indonesia established integrated service posts or "Posyandu" in villages during the 1980s for women volunteers as health advocates. FP/MCH was later integrated in these health posts. The service posts aim to reduce infant mortality and maternal mortality through growth monitoring of children aged under five years, provision of FP, nutrition services for pregnant mothers, immunization, and monitoring of high-risk pregnancies. Trained volunteers and community people are aides to either government personnel or nongovernmental (NGO) workers. The Indonesian government FP program evolved from a program "for" the people, to "with" the people, and finally "by" the people. Fees for contraception, which are still below retail prices, are being introduced as a means of achieving sustainability. The government trains doctors and midwives in FP. NGOs such as Yayasan Kusuma Buana (YKB) in Jakarta provide a mix of quality services. YKB is active in promoting awareness of FP. Community outreach is achieved through mothers' classes, urban Posyandu services, and training of traditional birth attendants. The Indonesian Planned Parenthood Association maintains self-reliance programs in FP/MCH. Day-care centers and youth counseling centers are used in promoting FP/MCH. YKB methods were demonstrated for workshop participants (posters used in local shops and awareness activities for school health programs). Workshop participants were exposed to many activities in FP/MCH. Participants learned the importance of government commitment and the importance of people's acceptance that FP is necessary for improving the quality of life.

  14. Driving Force Based Design of Cyclic Distillation

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Fjordbak; Huusom, Jakob Kjøbsted; Abildskov, Jens

    2017-01-01

    with mixed phase feeds. A range of binary test cases, benzene toluene, methanol water, and ethanol water, are evaluated. The advantage of the design approach in cyclic distillation is shown to be analogous to the advantages obtained in conventional continuous distillation, including a minimal utility...

  15. Amenity migration - driving force for rural development?

    Czech Academy of Sciences Publication Activity Database

    Bartoš, Michael; Kušová, Drahomíra; Těšitel, Jan

    2007-01-01

    Roč. 4, 3-4 (2007), s. 57-69 ISSN 1841-0375 R&D Projects: GA ČR(CZ) GA403/07/0714 Institutional research plan: CEZ:AV0Z60870520 Keywords : Amenity migration * tourism * rural development Subject RIV: AO - Sociology, Demography

  16. Thermodynamic driving force for rafting in superalloys

    CSIR Research Space (South Africa)

    Nabarro, FRN

    1996-08-01

    Full Text Available - and three-dimensional systems behave similarly. The initial plastic strain in gamma' is anelastic and in principle reversible. When the plastic strain exceeds m delta, platelets perpendicular to the stress axis are formed if the product sigma delta...

  17. The driving force role of ruthenacyclobutanes

    KAUST Repository

    Vummaleti, Sai V. C.

    2015-02-07

    DFT calculations have been used to determine the thermodynamic and kinetic preference for ruthenacyclobutanes resulting from the experimentally proposed interconversion pathways (olefin and alkylidene rotations) through the investigation of cross-metathesis reaction mechanism for neutral Grubbs catalyst, RuCl2(=CHEt)NHC (A), with ethylene and 1-butene as the substrates. Our results show that although the proposed interconversions are feasible due to the predicted low energy barriers (2-6 kcal/mol), the formation of ruthenacyclobutane is kinetically favored over the competitive reactions involving alkylidene rotations. In comparison with catalyst A, the reaction energy profile for cationic Piers catalyst [RuCl2(=CHPCy3)NHC+] (B) is more endothermic in nature with both ethylene and 1-butene substrates.

  18. The driving force role of ruthenacyclobutanes

    KAUST Repository

    Vummaleti, Sai V. C.; Cavallo, Luigi; Poater, Albert

    2015-01-01

    DFT calculations have been used to determine the thermodynamic and kinetic preference for ruthenacyclobutanes resulting from the experimentally proposed interconversion pathways (olefin and alkylidene rotations) through the investigation of cross-metathesis reaction mechanism for neutral Grubbs catalyst, RuCl2(=CHEt)NHC (A), with ethylene and 1-butene as the substrates. Our results show that although the proposed interconversions are feasible due to the predicted low energy barriers (2-6 kcal/mol), the formation of ruthenacyclobutane is kinetically favored over the competitive reactions involving alkylidene rotations. In comparison with catalyst A, the reaction energy profile for cationic Piers catalyst [RuCl2(=CHPCy3)NHC+] (B) is more endothermic in nature with both ethylene and 1-butene substrates.

  19. SINEs as driving forces in genome evolution.

    Science.gov (United States)

    Schmitz, J

    2012-01-01

    SINEs are short interspersed elements derived from cellular RNAs that repetitively retropose via RNA intermediates and integrate more or less randomly back into the genome. SINEs propagate almost entirely vertically within their host cells and, once established in the germline, are passed on from generation to generation. As non-autonomous elements, their reverse transcription (from RNA to cDNA) and genomic integration depends on the activity of the enzymatic machinery of autonomous retrotransposons, such as long interspersed elements (LINEs). SINEs are widely distributed in eukaryotes, but are especially effectively propagated in mammalian species. For example, more than a million Alu-SINE copies populate the human genome (approximately 13% of genomic space), and few master copies of them are still active. In the organisms where they occur, SINEs are a challenge to genomic integrity, but in the long term also can serve as beneficial building blocks for evolution, contributing to phenotypic heterogeneity and modifying gene regulatory networks. They substantially expand the genomic space and introduce structural variation to the genome. SINEs have the potential to mutate genes, to alter gene expression, and to generate new parts of genes. A balanced distribution and controlled activity of such properties is crucial to maintaining the organism's dynamic and thriving evolution. Copyright © 2012 S. Karger AG, Basel.

  20. Tourism: spatial dimension and driving force

    OpenAIRE

    Lourenço, Nelson; Jorge, Rosário

    2003-01-01

    Spatial and socio-economic impacts of tourism have been quite significant in some regions, causing changes in the economic structure, stimulating some sectors and displacing others. Tourism creates pressures on different domains—natural resources and environment, the built environment, and hospitality and cultural resources. The tourism infrastructure has impacted on the existing social, economic, and environmental dynamics of Goan society. Some of the tourism-related influences are discu...

  1. Pattern-formation under acoustic driving forces

    Science.gov (United States)

    Valverde, Jose Manuel

    2015-07-01

    Chemical and metallurgical processes enhanced by high intensity acoustic waves, thermoacoustic engines and refrigerators, fuel rods in nuclear reactors, heat exchanger tubes, offshore and vibrating structures, solar thermal collectors, acoustic levitators, microfluidic devices, cycling, musical acoustics, blood flow through veins/arteries, hearing in the mammalian ear, carbon nanotube loudspeakers, etc. The evolution of a myriad of processes involving the oscillation of viscous fluids in the presence of solid boundaries is up to a certain extent influenced by acoustic streaming. In addition to the sound field, viscous energy dissipation at the fluid-solid boundary causes a time-independent fluid circulation, which can lead to a significant enhancement of heat, mass and momentum transfer at large oscillation amplitudes. A particularly relevant phenomenon that can be notably affected by acoustic streaming is the promotion of sound waves by temperature gradients or viceversa (thermoacoustics), which is at the basis of potentially efficient and environmental friendly engines and refrigerators that have attracted a renewed interest in the last years. In the present manuscript, historical developments and the underlying basic physics behind acoustic streaming and thermoacoustics are reviewed from an unifying perspective.

  2. Control rod drives

    International Nuclear Information System (INIS)

    Furumitsu, Yutaka.

    1981-01-01

    Purpose: To improve the reliability of a device for driving an LMFBR type reactor control rod by providing a buffer unit having a stationary electromagnetic coil and a movable electromagnetic coil in the device to thereby avord impact stress at scram time and to simplify the structure of the buffer unit. Constitution: A non-contact type buffer unit is constructed with a stationary electromagnetic coil, a cable for the stationary coil, a movable electromagnetic coil, a spring cable for the movable coil, and a backup coil spring or the like. Force produced at scram time is delivered without impact by the attracting or repelling force between the stationary coil and the movable coil of the buffer unit. Accordingly, since the buffer unit is of a non-contact type, there is no mechanical impact and thus no large impact stress, and as it has simple configuration, the reliability is improved and the maintenance can be conducted more easily. (Yoshihara, H.)

  3. Semiclassical instability of warp drives

    Energy Technology Data Exchange (ETDEWEB)

    Barcelo, C [Instituto de Astrofisica de Andalucia, IAA-CSIC, Glorieta de la Astronomia s/n, 18008 Granada (Spain); Finazzi, S; Liberati, S, E-mail: carlos@iaa.e, E-mail: finazzi@sissa.i, E-mail: liberati@sissa.i

    2010-05-01

    Warp drives, at least theoretically, provide a way to travel at superluminal speeds. However, even if one succeeded in providing the necessary exotic matter to construct them, it would still be necessary to check whether they would survive to the switching on of quantum effects. In this contribution we will report on the behaviour of the Renormalized Stress-Energy Tensor (RSET) in the spacetimes associated with superluminal warp drives. We find that the RSET will exponentially grow in time close to the front wall of the superluminal bubble, hence strongly supporting the conclusion that the warp-drive geometries are unstable against semiclassical back-reaction.

  4. Differential Survival between Visual Environments Supports a Role of Divergent Sensory Drive in Cichlid Fish Speciation.

    Science.gov (United States)

    Maan, Martine E; Seehausen, Ole; Groothuis, Ton G G

    2017-01-01

    Identifying the selective forces that initiate ecological speciation is a major challenge in evolutionary biology. Sensory drive has been implicated in speciation in various taxa, largely based on phenotype-environment correlations and signatures of selection in sensory genes. Here, we present a reciprocal transplant experiment revealing species differences in performance in alternative visual environments, consistent with speciation by divergent sensory drive. The closely related cichlids Pundamilia pundamilia and Pundamilia nyererei inhabit different visual environments in Lake Victoria and show associated differences in visual system properties. Mimicking the two light environments in the laboratory, we find a substantial reduction in survival of both species when reared in the other species' visual environment. This implies that the observed differences in Pundamilia color vision are indeed adaptive and substantiates the implicit assumption in sensory drive speciation models that divergent environmental selection is strong enough to drive divergence in sensory properties.

  5. Novel AC Servo Rotating and Linear Composite Driving Device for Plastic Forming Equipment

    Science.gov (United States)

    Liang, Jin-Tao; Zhao, Sheng-Dun; Li, Yong-Yi; Zhu, Mu-Zhi

    2017-07-01

    The existing plastic forming equipment are mostly driven by traditional AC motors with long transmission chains, low efficiency, large size, low precision and poor dynamic response are the common disadvantages. In order to realize high performance forming processes, the driving device should be improved, especially for complicated processing motions. Based on electric servo direct drive technology, a novel AC servo rotating and linear composite driving device is proposed, which features implementing both spindle rotation and feed motion without transmission, so that compact structure and precise control can be achieved. Flux switching topology is employed in the rotating drive component for strong robustness, and fractional slot is employed in the linear direct drive component for large force capability. Then the mechanical structure for compositing rotation and linear motion is designed. A device prototype is manufactured, machining of each component and the whole assembly are presented respectively. Commercial servo amplifiers are utilized to construct the control system of the proposed device. To validate the effectiveness of the proposed composite driving device, experimental study on the dynamic test benches are conducted. The results indicate that the output torque can attain to 420 N·m and the dynamic tracking errors are less than about 0.3 rad in the rotating drive. the dynamic tracking errors are less than about 1.6 mm in the linear feed. The proposed research provides a method to construct high efficiency and accuracy direct driving device in plastic forming equipment.

  6. Safe driving for teens

    Science.gov (United States)

    Driving and teenagers; Teens and safe driving; Automobile safety - teenage drivers ... months before taking friends as passengers. Teenage-related driving deaths occur more often in certain conditions. OTHER SAFETY TIPS FOR TEENS Reckless driving is still a ...

  7. Characterization of New Isolates of Apricot vein clearing-associated virus and of a New Prunus-Infecting Virus: Evidence for Recombination as a Driving Force in Betaflexiviridae Evolution.

    Directory of Open Access Journals (Sweden)

    Armelle Marais

    Full Text Available Double stranded RNAs from Prunus samples gathered from various surveys were analyzed by a deep-sequencing approach. Contig annotations revealed the presence of a potential new viral species in an Azerbaijani almond tree (Prunus amygdalus and its genome sequence was completed. Its genomic organization is similar to that of the recently described Apricot vein clearing associated virus (AVCaV for which two new isolates were also characterized, in a similar fashion, from two Japanese plums (Prunus salicina from a French germplasm collection. The amino acid identity values between the four proteins encoded by the genome of the new virus have identity levels with those of AVCaV which fall clearly outside the species demarcation criteria. The new virus should therefore be considered as a new species for which the name of Caucasus prunus virus (CPrV has been proposed. Phylogenetic relationships and nucleotide comparisons suggested that together with AVCaV, CPrV could define a new genus (proposed name: Prunevirus in the family Betaflexiviridae. A molecular test targeting both members of the new genus was developed, allowing the detection of additional AVCaV isolates, and therefore extending the known geographical distribution and the host range of AVCaV. Moreover, the phylogenetic trees reconstructed with the amino acid sequences of replicase, movement and coat proteins of representative Betaflexiviridae members suggest that Citrus leaf blotch virus (CLBV, type member of the genus Citrivirus may have evolved from a recombination event involving a Prunevirus, further highlighting the importance of recombination as a driving force in Betaflexiviridae evolution. The sequences reported in the present manuscript have been deposited in the GenBank database under accession numbers KM507061-KM504070.

  8. Measurement of Driving Terms

    CERN Document Server

    Schmidt, F; Faus-Golfe, A

    2001-01-01

    In 2000 a series of MDs has been performed at the SPS to measure resonance driving terms. Theory predicts that these terms can be determined by harmonic analysis of BPM data recorded after applying single kicks at various amplitudes. Strong sextupoles were introduced to create a sizeable amount of nonlinearities. Experiments at injection energy (26 GeV) with single bunch as well as one experiment at 120 GeV with 84 bunches were carried out. The expected nonlinear content is compared to the experimenteal observation.

  9. Control rod drives

    International Nuclear Information System (INIS)

    Oonuki, Koji.

    1981-01-01

    Purpose: To increase the driving speed of control rods at rapid insertion with an elongate control rod and an extension pipe while ensuring sufficient buffering performance in a short buffering distance, by providing a plurality of buffers to an extension pipe between a control rod drive source and a control rod in LMFBR type reactor. Constitution: First, second and third buffers are respectively provided to an acceleration piston, an extension pipe and a control rod respectively and the insertion positions for each of the buffers are displaced orderly from above to below. Upon disconnection of energizing current for an electromagnet, the acceleration piston, the extension pipe and the control rod are rapidly inserted in one body. The first, second and third buffers are respectively actuated at each of their falling strokes upon rapid insertion respectively, and the acceleration piston, the extension pipe and the control rod receive the deceleration effect in the order correspondingly. Although the compression force is applied to the control rod only near the stroke end, it does not cause deformation. (Kawakami, Y.)

  10. Rotating magnetic field current drive-theory and experiment

    International Nuclear Information System (INIS)

    Donnelly, I.J.

    1989-01-01

    Rotating magnetic fields have been used to drive plasma current and establish a range of compact torus configurations, named rotamaks. The current drive mechanism involves a ponderomotive force acting on the electron fluid. Recent extensions of the theory indicate that this method is most suitable for driving currents in directions perpendicular to the steady magnetic fields

  11. Current Drive in a Ponderomotive Potential with Sign Reversal

    Energy Technology Data Exchange (ETDEWEB)

    N.J. Fisch; J.M. Rax; I.Y. Dodin

    2003-07-30

    Noninductive current drive can be accomplished through ponderomotive forces with high efficiency when the potential changes sign over the interaction region. The effect can practiced upon both ions and electrons. The current drive efficiencies, in principle, might be higher than those possible with conventional radio-frequency current-drive techniques, since different considerations come into play.

  12. Current Drive in a Ponderomotive Potential with Sign Reversal

    International Nuclear Information System (INIS)

    Fisch, N.J.; Rax, J.M.; Dodin, I.Y.

    2003-01-01

    Noninductive current drive can be accomplished through ponderomotive forces with high efficiency when the potential changes sign over the interaction region. The effect can practiced upon both ions and electrons. The current drive efficiencies, in principle, might be higher than those possible with conventional radio-frequency current-drive techniques, since different considerations come into play

  13. Chaos as an intermittently forced linear system.

    Science.gov (United States)

    Brunton, Steven L; Brunton, Bingni W; Proctor, Joshua L; Kaiser, Eurika; Kutz, J Nathan

    2017-05-30

    Understanding the interplay of order and disorder in chaos is a central challenge in modern quantitative science. Approximate linear representations of nonlinear dynamics have long been sought, driving considerable interest in Koopman theory. We present a universal, data-driven decomposition of chaos as an intermittently forced linear system. This work combines delay embedding and Koopman theory to decompose chaotic dynamics into a linear model in the leading delay coordinates with forcing by low-energy delay coordinates; this is called the Hankel alternative view of Koopman (HAVOK) analysis. This analysis is applied to the Lorenz system and real-world examples including Earth's magnetic field reversal and measles outbreaks. In each case, forcing statistics are non-Gaussian, with long tails corresponding to rare intermittent forcing that precedes switching and bursting phenomena. The forcing activity demarcates coherent phase space regions where the dynamics are approximately linear from those that are strongly nonlinear.The huge amount of data generated in fields like neuroscience or finance calls for effective strategies that mine data to reveal underlying dynamics. Here Brunton et al.develop a data-driven technique to analyze chaotic systems and predict their dynamics in terms of a forced linear model.

  14. Efficient Driving of Piezoelectric Transducers Using a Biaxial Driving Technique.

    Directory of Open Access Journals (Sweden)

    Samuel Pichardo

    Full Text Available Efficient driving of piezoelectric materials is desirable when operating transducers for biomedical applications such as high intensity focused ultrasound (HIFU or ultrasound imaging. More efficient operation reduces the electric power required to produce the desired bioeffect or contrast. Our preliminary work [Cole et al. Journal of Physics: Condensed Matter. 2014;26(13:135901.] suggested that driving transducers by applying orthogonal electric fields can significantly reduce the coercivity that opposes ferroelectric switching. We present here the experimental validation of this biaxial driving technique using piezoelectric ceramics typically used in HIFU. A set of narrow-band transducers was fabricated with two sets of electrodes placed in an orthogonal configuration (following the propagation and the lateral mode. The geometry of the ceramic was chosen to have a resonance frequency similar for the propagation and the lateral mode. The average (± s.d. resonance frequency of the samples was 465.1 (± 1.5 kHz. Experiments were conducted in which each pair of electrodes was driven independently and measurements of effective acoustic power were obtained using the radiation force method. The efficiency (acoustic/electric power of the biaxial driving method was compared to the results obtained when driving the ceramic using electrodes placed only in the pole direction. Our results indicate that the biaxial method increases efficiency from 50% to 125% relative to the using a single electric field.

  15. Stirring Strongly Coupled Plasma

    CERN Document Server

    Fadafan, Kazem Bitaghsir; Rajagopal, Krishna; Wiedemann, Urs Achim

    2009-01-01

    We determine the energy it takes to move a test quark along a circle of radius L with angular frequency w through the strongly coupled plasma of N=4 supersymmetric Yang-Mills (SYM) theory. We find that for most values of L and w the energy deposited by stirring the plasma in this way is governed either by the drag force acting on a test quark moving through the plasma in a straight line with speed v=Lw or by the energy radiated by a quark in circular motion in the absence of any plasma, whichever is larger. There is a continuous crossover from the drag-dominated regime to the radiation-dominated regime. In the crossover regime we find evidence for significant destructive interference between energy loss due to drag and that due to radiation as if in vacuum. The rotating quark thus serves as a model system in which the relative strength of, and interplay between, two different mechanisms of parton energy loss is accessible via a controlled classical gravity calculation. We close by speculating on the implicati...

  16. Extended driving impairs nocturnal driving performances.

    Directory of Open Access Journals (Sweden)

    Patricia Sagaspe

    Full Text Available Though fatigue and sleepiness at the wheel are well-known risk factors for traffic accidents, many drivers combine extended driving and sleep deprivation. Fatigue-related accidents occur mainly at night but there is no experimental data available to determine if the duration of prior driving affects driving performance at night. Participants drove in 3 nocturnal driving sessions (3-5 am, 1-5 am and 9 pm-5 am on open highway. Fourteen young healthy men (mean age [+/-SD] = 23.4 [+/-1.7] years participated Inappropriate line crossings (ILC in the last hour of driving of each session, sleep variables, self-perceived fatigue and sleepiness were measured. Compared to the short (3-5 am driving session, the incidence rate ratio of inappropriate line crossings increased by 2.6 (95% CI, 1.1 to 6.0; P<.05 for the intermediate (1-5 am driving session and by 4.0 (CI, 1.7 to 9.4; P<.001 for the long (9 pm-5 am driving session. Compared to the reference session (9-10 pm, the incidence rate ratio of inappropriate line crossings were 6.0 (95% CI, 2.3 to 15.5; P<.001, 15.4 (CI, 4.6 to 51.5; P<.001 and 24.3 (CI, 7.4 to 79.5; P<.001, respectively, for the three different durations of driving. Self-rated fatigue and sleepiness scores were both positively correlated to driving impairment in the intermediate and long duration sessions (P<.05 and increased significantly during the nocturnal driving sessions compared to the reference session (P<.01. At night, extended driving impairs driving performances and therefore should be limited.

  17. 东北老工业区生态安全动态演变过程及驱动力%Dynamic evolution and driving forces of ecological security in the Traditional Industrial Area of northeastern China

    Institute of Scientific and Technical Information of China (English)

    唐呈瑞; 逯承鹏; 杨青; 姜璐; 任婉侠; 薛冰

    2017-01-01

    Ecological security is as important as national,economic,and financial security and has become the main constraint of future socio-economic security.The Traditional Industrial Area of northeastern China is an important traditional industrial and grain production base of China,and its ecological security is related to the implementation of sustainable development strategies.Based on the emergy-ecological footprint model,the ecological security in Traditional Industrial Area of northeastern China was quantitatively evaluated from 2000 to 2014,followed by a scenario analysis on the driving forces of the ecological security using a principal component analysis method.The results showed that,the value of emergy ecological-capacity per capita decreased from 0.66 to 0.64 hm2/cap,whereas the emergy-ecological footprint increased from 10.58 to 19.85 hm2/cap,which indicated that an ecological deficit existed in the Traditional Industrial Area of northeastern China.The ecological pressure in this area increased,showing an unsustainable development trend from 2000 to 2014.The ecological pressure index and ecological security levels gradually increasing,ecological security situation is deteriorating,ecological security issues to be urgent resolved.The ecological stress tended to be serious as a result of a combination of several factors,such as social,economic,population,resource,environmental,technological level,and land use degree.Finally,effective management strategies and suggestions to improve the ecological security of the Traditional Industrial Area of northeastern China were proposed.%生态安全与国防安全、经济安全、金融安全等已具有同等重要的战略地位,并成为未来经济社会安全的主要约束.东北老工业区作为我国重要的老工业基地及粮食生产基地,其生态安全状况关系着中国可持续发展战略的实施.采用能值-生态足迹模型,对东北老工业区2000-2014年生态安全动态演变过程进行

  18. LAND-USE CHANGE AND ITS DRIVING FORCES OF "THREE PARALLEL RIVERS" IN NORTHWEST YUNNAN PROVINCE%滇西北三江并流区土地利用变化研究

    Institute of Scientific and Technical Information of China (English)

    王金亮; 蒋莲芳; 李瑞林

    2005-01-01

    counties that prefectures located (such as Shangri-la, Lushui and Lijiang) was faster than of that othercounties. (5) The main driving forces of LUCC of this area were social-economy factors, including population growth,science technology development, growth of economy, inheritance and development of ethnic cultures, changes of policy and laws related to resources use and environmental protection.

  19. Do emotions drive psychosis?

    Directory of Open Access Journals (Sweden)

    João G. Ribeiro

    2012-12-01

    Full Text Available Introduction: How important is the emotional life of persons who manifest psychotic symptoms? Aims: The aim of this paper is to review evidence on a causal role for emotions in psychotic processes. Methods: Selective review of literature on affective symptoms in psychoses, on emotions in the production of psychotic symptoms and on dopaminergic models of psychosis. Results: Affective symptoms are relevant across psychoses. Persons with schizophrenia have high levels of emotional reactivity and the intensification of negative affects not only is associated with but also precedes the intensification of psychotic symptoms, which is evidence that negative emotions drive the course of psychotic symptoms. Negative self‑representations are central in psychotic processes and can be the link between negative emotions and psychosis. Evidence favours the notion that persecutory delusions are consistent with negative affects and self‑representations, while grandiose delusions are consistent with a defensive amplification of positive affects and self‑representations. Shame has been proposed as the core emotional experience of psychosis, one in which the self becomes vulnerable to the external world, which is consistent with persecutory experiences. Assaults on the self, under the form of hostility in the family environment and society, are strong predictors of relapse and development of schizophrenia. Assaults on the self which induce social defeat are also strong stimulants of mesolimbic dopaminergic pathways, whose hyperactivity is associated with acute psychotic episodes and the experience of “aberrant salience”, put forward as a dopaminergic model of psychosis. Conclusions: The “defeat of the self” emerges as a central link that binds the experience of negative emotions to the expression of psychotic symptoms and its psychological and neurobiological correlates. The hypothesis gains support that the emotions related to that defeat control

  20. HARMONIC DRIVE SELECTION

    Directory of Open Access Journals (Sweden)

    Piotr FOLĘGA

    2014-03-01

    Full Text Available The variety of types and sizes currently in production harmonic drive is a problem in their rational choice. Properly selected harmonic drive must meet certain requirements during operation, and achieve the anticipated service life. The paper discusses the problems associated with the selection of the harmonic drive. It also presents the algorithm correct choice of harmonic drive. The main objective of this study was to develop a computer program that allows the correct choice of harmonic drive by developed algorithm.

  1. Analysis of Vehicle Steering and Driving Bifurcation Characteristics

    Directory of Open Access Journals (Sweden)

    Xianbin Wang

    2015-01-01

    Full Text Available The typical method of vehicle steering bifurcation analysis is based on the nonlinear autonomous vehicle model deriving from the classic two degrees of freedom (2DOF linear vehicle model. This method usually neglects the driving effect on steering bifurcation characteristics. However, in the steering and driving combined conditions, the tyre under different driving conditions can provide different lateral force. The steering bifurcation mechanism without the driving effect is not able to fully reveal the vehicle steering and driving bifurcation characteristics. Aiming at the aforementioned problem, this paper analyzed the vehicle steering and driving bifurcation characteristics with the consideration of driving effect. Based on the 5DOF vehicle system dynamics model with the consideration of driving effect, the 7DOF autonomous system model was established. The vehicle steering and driving bifurcation dynamic characteristics were analyzed with different driving mode and driving torque. Taking the front-wheel-drive system as an example, the dynamic evolution process of steering and driving bifurcation was analyzed by phase space, system state variables, power spectral density, and Lyapunov index. The numerical recognition results of chaos were also provided. The research results show that the driving mode and driving torque have the obvious effect on steering and driving bifurcation characteristics.

  2. Consistent Automation Solutions for Electrohydraulic Drives in Times of Industry 4.0

    OpenAIRE

    Köckemann, Albert; Birke, Benno

    2016-01-01

    Electrohydraulic drives are primarily used whenever a low power/weight ratio, a compact build and/or large forces are required for individual applications. These drives are often used together with electric drive technology in machines. However, in terms of automation, unlike electric drives, electrohydraulic drives are still largely connected via analog interfaces and centralized closed control loops today. To compensate for this competitive disadvantage of hydraulic drive technology and, at...

  3. A liquid helium piston pump with a superconducting drive

    International Nuclear Information System (INIS)

    Schmidt, C.

    1984-01-01

    This chapter describes a bellows pump where the driving force is achieved by an arrangement of three superconducting coils. The pump was designed for use in the supercritical helium flow circuit of the LCT-conductor test facility. The main advantage of the superconducting drive, compared to conventional pumps with external drive, is the compact design. Force transferring parts between 4.2 K and room temperature are not necessary. The pump was tested in a closed loop arrangement. The superconducting drive for a piston pump consists of a moving coil in a constant background field. Other coil configurations and the upscaling of the pump design are discussed

  4. Combination spindle-drive system for high precision machining

    Science.gov (United States)

    Gerth, Howard L.

    1977-07-26

    A combination spindle-drive is provided for fabrication of optical quality surface finishes. Both the spindle-and-drive utilize the spindle bearings for support, thereby removing the conventional drive-means bearings as a source of vibration. An airbearing spindle is modified to carry at the drive end a highly conductive cup-shaped rotor which is aligned with a stationary stator to produce torque in the cup-shaped rotor through the reaction of eddy currents induced in the rotor. This arrangement eliminates magnetic attraction forces and all force is in the form of torque on the cup-shaped rotor.

  5. Electric Vehicle - Economical driving

    DEFF Research Database (Denmark)

    Jensen, VCE, Steen V.; Schøn, Henriette

    1999-01-01

    Instruct the reader in getting most satisfaction out of an EV, especially concerning driving and loading.......Instruct the reader in getting most satisfaction out of an EV, especially concerning driving and loading....

  6. Dementia and driving

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000028.htm Dementia and driving To use the sharing features on ... please enable JavaScript. If your loved one has dementia , deciding when they can no longer drive may ...

  7. Gear bearing drive

    Science.gov (United States)

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

    2011-01-01

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

  8. <strong>>Synchronisation of glycolytic oscillations in a suspension of human neutrophilsstrong>>

    DEFF Research Database (Denmark)

    Brasen, Jens Christian; Poulsen, Allan K.; Olsen, Lars Folke

    Neutrophils are known to be able to synchronize their production of superoxide. We show that glycolysis is also synchronized in human neutrophils being in suspension and suggest that oscillations in glycolysis are driving the pulsatile production of superoxide. The synchronising agent remains so...... far unknown, however, much evident points to that it might be hydrogen peroxide or an intermediate in glycolysis....

  9. Antihistamines and driving safety.

    Science.gov (United States)

    O'Hanlon, J F

    1988-10-27

    The results of two placebo-controlled driving performance studies confirm laboratory data showing that the nonsedating antihistamine terfenadine does not influence the driving performance of users. The amplitude of vehicle weaving calculated for drivers who received this agent did not differ from control values. Neither terfenadine nor loratadine, another nonsedating antihistamine, potentiated the adverse effects of alcohol on driving performance.

  10. Driving After a Stroke

    Science.gov (United States)

    ... 23,2015 Can I drive after a stroke? Driving is often a major concern after someone has a stroke. It’s not unusual for stroke survivors to want to drive. Being able to get around after a stroke is important. Safety behind the wheel is even more important after ...

  11. Sequential Dependencies in Driving

    Science.gov (United States)

    Doshi, Anup; Tran, Cuong; Wilder, Matthew H.; Mozer, Michael C.; Trivedi, Mohan M.

    2012-01-01

    The effect of recent experience on current behavior has been studied extensively in simple laboratory tasks. We explore the nature of sequential effects in the more naturalistic setting of automobile driving. Driving is a safety-critical task in which delayed response times may have severe consequences. Using a realistic driving simulator, we find…

  12. Simple Driving Techniques

    DEFF Research Database (Denmark)

    Rosendahl, Mads

    2002-01-01

    -like language. Our aim is to extract a simple notion of driving and show that even in this tamed form it has much of the power of more general notions of driving. Our driving technique may be used to simplify functional programs which use function composition and will often be able to remove intermediate data...

  13. Resonant Activation in a Stochastic Hodgkin-Huxley Model: Interplay between noise and suprathreshold driving effect

    DEFF Research Database (Denmark)

    Pankratova, Evgeniya; Polovinkin, A.V.; Mosekilde, Erik

    2005-01-01

    The paper considers an excitable Hodgkin-Huxley system subjected to a strong periodic forcing in the presence of random noise. The influence of the forcing frequency on the response of the system is examined in the realm of suprathreshold amplitudes. Our results confirm that the presence of noise...... a minimum as functions of the forcing frequency. The destructive influence of noise on the interspike interval can also be reduced. With driving signals in a certain frequency range, the system can show stable periodic spiking even for relatively large noise intensities. Outside this frequency range, noise...... of similar intensity destroys the regularity of the spike trains by suppressing the generation of some of the spikes....

  14. How to Drive CARS in Reverse

    Science.gov (United States)

    2013-11-07

    and ‘heats’ this plasma creating an electron avalanche , analogous to the electric discharge used in traditional nitrogen lasers. These schemes are all... pulse . This pulse is then used to drive a coherent anti-Stokes Raman scattering scheme, resulting in a strong chemically specific signal propagating...generation of a backward propagating stimulated Raman pulse . This pulse is then used to drive a coherent anti-Stokes Raman scattering scheme, resulting in a

  15. The death drive in tourism studies

    NARCIS (Netherlands)

    Buda, Dorina Maria

    2015-01-01

    The psychoanalytical concept of the death drive postulated by Freud and Lacan refers to a constant force at the junction between life and death, which is not understood in a biological sense of physical demise of the body, nor in opposition to life. Tourist experiences in conflict zones can be more

  16. Control rod drive

    International Nuclear Information System (INIS)

    Okutani, Tetsuro.

    1988-01-01

    Purpose: To provide a simple and economical control rod drive using a control circuit requiring no pulse circuit. Constitution: Control rods in a BWR type reactor are driven by hydraulic pressure and inserted or withdrawn in the direction of applying the hydraulic pressure. The direction of the hydraulic pressure is controlled by a direction control valve. Since the driving for the control rod is extremely important in view of the operation, a self diagnosis function is disposed for rapid inspection of possible abnormality. In the present invention, two driving contacts are disposed each by one between the both ends of a solenoid valve of the direction control valve for driving the control rod and the driving power source, and diagnosis is conducted by alternately operating them. Therefore, since it is only necessary that the control circuit issues a driving instruction only to one of the two driving contacts, the pulse circuit is no more required. Further, since the control rod driving is conducted upon alignment of the two driving instructions, the reliability of the control rod drive can be improved. (Horiuchi, T.)

  17. Abortion: Strong's counterexamples fail

    DEFF Research Database (Denmark)

    Di Nucci, Ezio

    2009-01-01

    This paper shows that the counterexamples proposed by Strong in 2008 in the Journal of Medical Ethics to Marquis's argument against abortion fail. Strong's basic idea is that there are cases--for example, terminally ill patients--where killing an adult human being is prima facie seriously morally...

  18. Strong Langmuir turbulence

    International Nuclear Information System (INIS)

    Goldman, M.V.

    1984-01-01

    After a brief discussion of beam-excited Langmuir turbulence in the solar wind, we explain the criteria for wave-particle, three-wave and strong turbulence interactions. We then present the results of a numerical integration of the Zakharov equations, which describe the strong turbulence saturation of a weak (low-density) high energy, bump-on-tail beam instability. (author)

  19. Using driving simulators to assess driving safety.

    Science.gov (United States)

    Boyle, Linda Ng; Lee, John D

    2010-05-01

    Changes in drivers, vehicles, and roadways pose substantial challenges to the transportation safety community. Crash records and naturalistic driving data are useful for examining the influence of past or existing technology on drivers, and the associations between risk factors and crashes. However, they are limited because causation cannot be established and technology not yet installed in production vehicles cannot be assessed. Driving simulators have become an increasingly widespread tool to understand evolving and novel technologies. The ability to manipulate independent variables in a randomized, controlled setting also provides the added benefit of identifying causal links. This paper introduces a special issue on simulator-based safety studies. The special issue comprises 25 papers that demonstrate the use of driving simulators to address pressing transportation safety problems and includes topics as diverse as neurological dysfunction, work zone design, and driver distraction. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  20. Optimization of spent fuel pool weir gate driving mechanism

    Science.gov (United States)

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

    2018-04-01

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

  1. Current drive in a ponderomotive potential with sign reversal

    International Nuclear Information System (INIS)

    Fisch, N.J.; Dodin, I.Y.; Rax, J.M.

    2003-01-01

    Noninductive current drive can be accomplished through ponderomotive forces with high efficiency when the potential changes sign over the interaction region. The effect, which operates somewhat like a Maxwell demon, can be practiced upon both ions and electrons. The current-drive efficiencies, in principle, might be higher than those possible with conventional rf current-drive techniques. It remains, however, for us to identify how the effect might be implemented in a magnetic fusion device in a practical manner

  2. Superluminal warp drive

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Diaz, Pedro F. [Colina de los Chopos, Centro de Fisica ' Miguel A. Catalan' , Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain)], E-mail: p.gonzalezdiaz@imaff.cfmac.csic.es

    2007-09-20

    In this Letter we consider a warp drive spacetime resulting from that suggested by Alcubierre when the spaceship can only travel faster than light. Restricting to the two dimensions that retains most of the physics, we derive the thermodynamic properties of the warp drive and show that the temperature of the spaceship rises up as its apparent velocity increases. We also find that the warp drive spacetime can be exhibited in a manifestly cosmological form.

  3. PMBLDC motor drive with power factor correction controller

    DEFF Research Database (Denmark)

    George, G.J.; Ramachandran, Rakesh; Arun, N.

    2012-01-01

    reliability, and low maintenance requirements. The proposed Power Factor Controller topology improves power quality by improving performance of PMBLDCM drive, such as reduction of AC main current harmonics, near unity power factor. PFC converter forces the drive to draw sinusoidal supply current in phase...

  4. Proceedings of the international conference on maglev and linear drives

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    This book contains papers presented at a conference on Maglev and linear drives. Topics covered include: Development of superconducting magnets for the Canadian electrodynamic Maglev vehicle; Power supply system to drive HSST - Expo '86; and Thrust and levitation force characteristics of linear synchronous motors

  5. CAE DEVELOPMENT OF PRECESSIONAL DRIVES USING AUTODESK INVENTOR PLATFORM

    Directory of Open Access Journals (Sweden)

    Ion BOSTAN

    2010-06-01

    Full Text Available The paper presents the modelling and simulation of precessional drives designed in two variants capable of high transmission ratio and torque for one stage compact construction. The constructions were designed in Inventor and also as multi body systems in otionInventor. The simulations of the drives provide information concerning positions, velocities, accelerations, point trajectories, forces and moments, energies, as well as contact forces at the contact between gear teeth and satellite teeth and other data concerning the system.

  6. Medications and impaired driving.

    Science.gov (United States)

    Hetland, Amanda; Carr, David B

    2014-04-01

    To describe the association of specific medication classes with driving outcomes and provide clinical recommendations. The MEDLINE and EMBASE databases were searched for articles published from January 1973 to June 2013 on classes of medications associated with driving impairment. The search included outcome terms such as automobile driving, motor vehicle crash, driving simulator, and road tests. Only English-language articles that contained findings from observational or interventional designs with ≥ 10 participants were included in this review. Cross-sectional studies, case series, and case reports were excluded. Driving is an important task and activity for the majority of adults. Some commonly prescribed medications have been associated with driving impairment measured by road performance, driving simulation, and/or motor vehicle crashes. This review of 30 studies identified findings with barbiturates, benzodiazepines, hypnotics, antidepressants, opioid and nonsteroidal analgesics, anticonvulsants, antipsychotics, antiparkinsonian agents, skeletal muscle relaxants, antihistamines, anticholinergic medications, and hypoglycemic agents. Additional studies of medication impact on sedation, sleep latency, and psychomotor function, as well as the role of alcohol, are also discussed. Psychotropic agents and those with central nervous system side effects were associated with measures of impaired driving performance. It is difficult to determine if such associations are actually a result of medication use or the medical diagnosis itself. Regardless, clinicians should be aware of the increased risk of impaired driving with specific classes of medications, educate their patients, and/or consider safer alternatives.

  7. Universal Drive Train Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This vehicle drive train research facility is capable of evaluating helicopter and ground vehicle power transmission technologies in a system level environment. The...

  8. Strong intrinsic motivation

    OpenAIRE

    Dessi, Roberta; Rustichini, Aldo

    2015-01-01

    A large literature in psychology, and more recently in economics, has argued that monetary rewards can reduce intrinsic motivation. We investigate whether the negative impact persists when intrinsic motivation is strong, and test this hypothesis experimentally focusing on the motivation to undertake interesting and challenging tasks, informative about individual ability. We find that this type of task can generate strong intrinsic motivation, that is impervious to the effect of monetary incen...

  9. Bitcoin Meets Strong Consistency

    OpenAIRE

    Decker, Christian; Seidel, Jochen; Wattenhofer, Roger

    2014-01-01

    The Bitcoin system only provides eventual consistency. For everyday life, the time to confirm a Bitcoin transaction is prohibitively slow. In this paper we propose a new system, built on the Bitcoin blockchain, which enables strong consistency. Our system, PeerCensus, acts as a certification authority, manages peer identities in a peer-to-peer network, and ultimately enhances Bitcoin and similar systems with strong consistency. Our extensive analysis shows that PeerCensus is in a secure state...

  10. Strong gravity and supersymmetry

    International Nuclear Information System (INIS)

    Chamseddine, Ali H.; Salam, A.; Strathdee, J.

    1977-11-01

    A supersymmetric theory is constructed for a strong f plus a weak g graviton, together with their accompanying massive gravitinos, by gaugin the gradel 0Sp(2,2,1)x 0Sp(2,2,1) structure. The mixing term between f and g fields, which makes the strong graviton massive, can be introduced through a spontaneous symmetry-breaking mechanism implemented in this note by constructing a non-linear realization of the symmetry group

  11. Dual role of an ac driving force and the underlying two distinct order–disorder transitions in the vortex phase diagram of Ca{sub 3}Ir{sub 4}Sn{sub 13}

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Santosh, E-mail: santoshkumar@phy.iitb.ac.in [Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076 (India); Singh, Ravi P.; Thamizhavel, A. [Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai 400005 (India); Tomy, C.V., E-mail: tomy@phy.iitb.ac.in [Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076 (India); Grover, A.K. [Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai 400005 (India); Department of Physics, Panjab University, Chandigarh 160014 (India)

    2014-11-15

    Highlights: • This work pertains to new findings related to a broad SMP anomaly. • Broad SMP prima facie encompasses two phase transformations in vortex matter. • We demarcated two phase boundaries pertaining to order–disorder transitions which have quasi first-order nature. - Abstract: We present distinct demarcation of the Bragg glass (BG) to multi-domain vortex glass (VG) transition line and the eventual amorphization of the VG phase in a weakly pinned single crystal of the superconducting compound Ca{sub 3}Ir{sub 4}Sn{sub 13} on the basis of comprehension of the different yields about the second magnetization peak (SMP) anomaly in the dc magnetization and the corresponding anomalous feature in the ac susceptibility measurements. The shaking by a small ac magnetic field, inevitably present in the ac susceptibility measurements, is seen to result in contrasting responses in two different portions of the field-temperature (H, T) phase space of the multi-domain VG. In one of the portions, embracing the BG to VG transition across the onset of the SMP anomaly, the ac drive is surprisingly seen to assist the transformation of the well ordered BG phase to a lesser ordered VG phase. The BG phase exists as a superheated state over a small portion of the VG space and this attests to the first order nature of the BG to VG transition.

  12. Piezoelectric drive circuit

    Science.gov (United States)

    Treu, C.A. Jr.

    1999-08-31

    A piezoelectric motor drive circuit is provided which utilizes the piezoelectric elements as oscillators and a Meacham half-bridge approach to develop feedback from the motor ground circuit to produce a signal to drive amplifiers to power the motor. The circuit automatically compensates for shifts in harmonic frequency of the piezoelectric elements due to pressure and temperature changes. 7 figs.

  13. Wrong-way driving.

    NARCIS (Netherlands)

    2006-01-01

    Wrong-way driving is a phenomenon that mainly happens on motorways. Although the number of wrong-way crashes is relatively limited, their consequences are much more severe than the consequences of other motorway injury crashes. The groups most often causing wrong-way driving accidents are young,

  14. Recognizing driving in haste

    NARCIS (Netherlands)

    Rendón-Vélez, E.

    2014-01-01

    One can often hear people discussing the reasons why a road accident has happened: “She had to pick up her kids in the school before four o’clock and she was driving in haste and careless”, “He was stressed, he wanted to reach the beginning of the football match, tried to drive faster and didn't

  15. Control rod drives

    International Nuclear Information System (INIS)

    Futatsugi, Masao.

    1980-01-01

    Purpose: To secure the reactor operation safety by the provision of a fluid pressure detecting section for control rod driving fluid and a control rod interlock at the midway of the flow pass for supplying driving fluid to the control rod drives. Constitution: Between a driving line and a direction control valve are provided a pressure detecting portion, an alarm generating device, and a control rod inhibition interlock. The driving fluid from a driving fluid source is discharged by way of a pump and a manual valve into the reactor in which the control rods and reactor fuels are contained. In addition, when the direction control valve is switched and the control rods are inserted and extracted by the control rod drives, the pressure in the driving line is always detected by the pressure detection section, whereby if abnormal pressure is resulted, the alarm generating device is actuated to warn the abnormality and the control rod inhibition interlock is actuated to lock the direction control valve thereby secure the safety operation of the reactor. (Seki, T.)

  16. Switched reluctance motor drives

    Indian Academy of Sciences (India)

    Davis RM, Ray WF, Blake RJ 1981 Inverter drive for switched reluctance: circuits and component ratings. Inst. Elec. Eng. Proc. B128: 126-136. Ehsani M. 1991 Position Sensor elimination technique for the switched reluctance motor drive. US Patent No. 5,072,166. Ehsani M, Ramani K R 1993 Direct control strategies based ...

  17. Self-driving carsickness

    NARCIS (Netherlands)

    Diels, C.; Bos, J.E.

    2016-01-01

    This paper discusses the predicted increase in the occurrence and severity of motion sickness in self-driving cars. Self-driving cars have the potential to lead to significant benefits. From the driver's perspective, the direct benefits of this technology are considered increased comfort and

  18. Self-driving carsickness.

    NARCIS (Netherlands)

    Diels, C.; Bos, J.E.

    2016-01-01

    This paper discusses the predicted increase in the occurrence and severity of motion sickness in self-driving cars. Self-driving cars have the potential to lead to significant benefits. From the driver's perspective, the direct benefits of this technology are considered increased comfort and

  19. Fundamentals of electrical drives

    CERN Document Server

    Veltman, André; De Doncker, Rik W

    2007-01-01

    Provides a comprehensive introduction to various aspects of electrical drive systems. This volume provides a presentation of dynamic generic models that cover all major electrical machine types and modulation/control components of a drive as well as dynamic and steady state analysis of transformers and electrical machines.

  20. Electric Vehicle - Economical driving

    DEFF Research Database (Denmark)

    Jensen, VCE, Steen V.; Schøn, Henriette

    1999-01-01

    How do you reduce the energy-wast when driving and loading EV's - or rather: How do I get more km/l out of an EV......How do you reduce the energy-wast when driving and loading EV's - or rather: How do I get more km/l out of an EV...

  1. Control rod drives

    International Nuclear Information System (INIS)

    Nakamura, Akira.

    1984-01-01

    Purpose: To enable to monitor the coupling state between a control rod and a control rod drive. Constitution: After the completion of a control rod withdrawal, a coolant pressure is applied to a control rod drive being adjusted so as to raise only the control rod drive and, in a case where the coupling between the control rod drive and the control rod is detached, the former is elevated till it contacts the control rod and then stopped. The actual stopping position is detected by an actual position detection circuit and compared with a predetermined position stored in a predetermined position detection circuit. If both of the positions are not aligned with each other, it is judged by a judging circuit that the control rod and the control rod drives are not combined. (Sekiya, K.)

  2. Strong moduli stabilization and phenomenology

    CERN Document Server

    Dudas, Emilian; Mambrini, Yann; Mustafayev, Azar; Olive, Keith A

    2013-01-01

    We describe the resulting phenomenology of string theory/supergravity models with strong moduli stabilization. The KL model with F-term uplifting, is one such example. Models of this type predict universal scalar masses equal to the gravitino mass. In contrast, A-terms receive highly suppressed gravity mediated contributions. Under certain conditions, the same conclusion is valid for gaugino masses, which like A-terms, are then determined by anomalies. In such models, we are forced to relatively large gravitino masses (30-1000 TeV). We compute the low energy spectrum as a function of m_{3/2}. We see that the Higgs masses naturally takes values between 125-130 GeV. The lower limit is obtained from the requirement of chargino masses greater than 104 GeV, while the upper limit is determined by the relic density of dark matter (wino-like).

  3. Spot Feeding Spheroidal Graphite Iron with Exothermic and Insulating Ram-Up Sleeves in Vertically Parted Moulds: Efficiency, Microstructure, Dimensional Accuracy, Deformation, and Driving Force and Feeding Criteria Identification

    DEFF Research Database (Denmark)

    Vedel-Smith, Nikolaj Kjelgaard

    feeders (ram-up sleeves) is investigated, showing that this new feeding approach can be used successfully to feed secluded sections inductile cast iron (EN-GJS-500-7). The feeder efficiency is tested using a high Silicon (Si) ductile iron (EN-GJS-450-10). The limits for the examined feeder configurations......Improvement of feeder technologies for energy savings in cast iron foundries is not only the title of the project behind this dissertation; it is a good idea that can improve casting yield and reduce production cost, and in turn strengthening the foundries competitive advantage. The approach...... of solidification. The dissertation provides a new approach to feeding secluded sections, a new characterisation of the underlying feeding forces, and new knowledge about the thermal deformation effects caused and controlled by feeding....

  4. Resonant driving of a nonlinear Hamiltonian system

    International Nuclear Information System (INIS)

    Palmisano, Carlo; Gervino, Gianpiero; Balma, Massimo; Devona, Dorina; Wimberger, Sandro

    2013-01-01

    As a proof of principle, we show how a classical nonlinear Hamiltonian system can be driven resonantly over reasonably long times by appropriately shaped pulses. To keep the parameter space reasonably small, we limit ourselves to a driving force which consists of periodic pulses additionally modulated by a sinusoidal function. The main observables are the average increase of kinetic energy and of the action variable (of the non-driven system) with time. Applications of our scheme aim for driving high frequencies of a nonlinear system with a fixed modulation signal.

  5. Earthquake source model using strong motion displacement

    Indian Academy of Sciences (India)

    The strong motion displacement records available during an earthquake can be treated as the response of the earth as the a structural system to unknown forces acting at unknown locations. Thus, if the part of the earth participating in ground motion is modelled as a known finite elastic medium, one can attempt to model the ...

  6. Possession attachment predicts cell phone use while driving.

    Science.gov (United States)

    Weller, Joshua A; Shackleford, Crystal; Dieckmann, Nathan; Slovic, Paul

    2013-04-01

    Distracted driving has become an important public health concern. However, little is known about the predictors of this health-risking behavior. One overlooked risk factor for distracted driving is the perceived attachment that one feels toward his or her phone. Prior research has suggested that individuals develop bonds toward objects, and qualitative research suggests that the bond between young drivers and their phones can be strong. It follows that individuals who perceive a strong attachment to their phone would be more likely to use it, even when driving. In a nationally representative sample of young drivers (17-28 years), participants (n = 1,006) completed a survey about driving behaviors and phone use. Risk perception surrounding cell phone use while driving and perceived attachment to one's phone were assessed by administering factor-analytically derived scales that were created as part of a larger project. Attachment toward one's phone predicted the proportion of trips in which a participant reported using their cell phone while driving, beyond that accounted for by risk perception and overall phone use. Further, attachment predicted self-reported distracted driving behaviors, such as the use of social media while driving. Attachment to one's phone may be an important but overlooked risk factor for the engagement of potentially health-risking driving behaviors. Understanding that phone attachment may adversely affect driving behaviors has the potential to inform prevention and intervention efforts designed to reduce distracted driving behaviors, especially in young drivers. 2013 APA, all rights reserved

  7. Dual field theory of strong interactions

    International Nuclear Information System (INIS)

    Akers, D.

    1987-01-01

    A dual field theory of strong interactions is derived from a Lagrangian of the Yang-Mills and Higgs fields. The existence of a magnetic monopole of mass 2397 MeV and Dirac charge g = (137/2)e is incorporated into the theory. Unification of the strong, weak, and electromagnetic forces is shown to converge at the mass of the intermediate vector boson W/sup +/-/. The coupling constants of the strong and weak interactions are derived in terms of the fine-structure constant α = 1/137

  8. Strongly interacting Fermi gases

    Directory of Open Access Journals (Sweden)

    Bakr W.

    2013-08-01

    Full Text Available Strongly interacting gases of ultracold fermions have become an amazingly rich test-bed for many-body theories of fermionic matter. Here we present our recent experiments on these systems. Firstly, we discuss high-precision measurements on the thermodynamics of a strongly interacting Fermi gas across the superfluid transition. The onset of superfluidity is directly observed in the compressibility, the chemical potential, the entropy, and the heat capacity. Our measurements provide benchmarks for current many-body theories on strongly interacting fermions. Secondly, we have studied the evolution of fermion pairing from three to two dimensions in these gases, relating to the physics of layered superconductors. In the presence of p-wave interactions, Fermi gases are predicted to display toplogical superfluidity carrying Majorana edge states. Two possible avenues in this direction are discussed, our creation and direct observation of spin-orbit coupling in Fermi gases and the creation of fermionic molecules of 23Na 40K that will feature strong dipolar interactions in their absolute ground state.

  9. A strong comeback

    International Nuclear Information System (INIS)

    Marier, D.

    1992-01-01

    This article presents the results of a financial rankings survey which show a strong economic activity in the independent energy industry. The topics of the article include advisor turnover, overseas banks, and the increase in public offerings. The article identifies the top project finance investors for new projects and restructurings and rankings for lenders

  10. Direct Lorentz force compensation flowmeter for electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Vasilyan, S., E-mail: suren.vasilyan@tu-ilmenau.de; Froehlich, Th. [Institute of Process Measurement and Sensor Technology, Ilmenau University of Technology, 98684 Ilmenau (Germany)

    2014-12-01

    A simplified method of contactless Lorentz force (LF) measurements for flow meters on electrolytes is described and realized. Modification and comparative representation are discussed against recently well-developed methods. Based on the catapult effect, that current carrying conductor experiences a repulsive force in a magnetic field, we demonstrate force measurement method of LF velocimetry applications by commonly known “electromagnetic force” compensation principle. Measurement approach through zero point stability is considered to minimize mechanical influences and avoid gravimetric uncertainties. Here, the current carrying wires are static fixed in the vicinity of magnet system at zero point stable position, while occurring deflection of magnets by electrolyte flow is compensated by external applied current within wires. Measurements performed by developed servo-system which drives control loop by means of optical position sensor for simplified (i) single wire and (ii) coil-like extended compensation schemes. Guided by experiments on electrolyte flow, we demonstrate the applicability of adopted principle for conductivities ranging from 2 to 20 S/m. Further improvements are discussed in agreement with the parameters of demonstration setup, straightforward theory, and experimental results. We argue that this method is potentially suitable for: (a) applications with higher conductivity like molten metal (order of 10{sup 6 }S/m) assuming spatial configuration of setup and (b) for lower range of conductivity (below 1 S/m) while this is strongly subject to stiffness of system and noise mainly mechanical and thermal radiations.

  11. Turbulent current drive mechanisms

    Science.gov (United States)

    McDevitt, Christopher J.; Tang, Xian-Zhu; Guo, Zehua

    2017-08-01

    Mechanisms through which plasma microturbulence can drive a mean electron plasma current are derived. The efficiency through which these turbulent contributions can drive deviations from neoclassical predictions of the electron current profile is computed by employing a linearized Coulomb collision operator. It is found that a non-diffusive contribution to the electron momentum flux as well as an anomalous electron-ion momentum exchange term provide the most efficient means through which turbulence can modify the mean electron current for the cases considered. Such turbulent contributions appear as an effective EMF within Ohm's law and hence provide an ideal means for driving deviations from neoclassical predictions.

  12. Fast wave current drive

    International Nuclear Information System (INIS)

    Goree, J.; Ono, M.; Colestock, P.; Horton, R.; McNeill, D.; Park, H.

    1985-07-01

    Fast wave current drive is demonstrated in the Princeton ACT-I toroidal device. The fast Alfven wave, in the range of high ion-cyclotron harmonics, produced 40 A of current from 1 kW of rf power coupled into the plasma by fast wave loop antenna. This wave excites a steady current by damping on the energetic tail of the electron distribution function in the same way as lower-hybrid current drive, except that fast wave current drive is appropriate for higher plasma densities

  13. Identifying Method of Drunk Driving Based on Driving Behavior

    Directory of Open Access Journals (Sweden)

    Xiaohua Zhao

    2011-05-01

    Full Text Available Drunk driving is one of the leading causes contributing to traffic crashes. There are numerous issues that need to be resolved with the current method of identifying drunk driving. Driving behavior, with the characteristic of real-time, was extensively researched to identify impaired driving behaviors. In this paper, the drives with BACs above 0.05% were defined as drunk driving state. A detailed comparison was made between normal driving and drunk driving. The experiment in driving simulator was designed to collect the driving performance data of the groups. According to the characteristics analysis for the effect of alcohol on driving performance, seven significant indicators were extracted and the drunk driving was identified by the Fisher Discriminant Method. The discriminant function demonstrated a high accuracy of classification. The optimal critical score to differentiate normal from drinking state was found to be 0. The evaluation result verifies the accuracy of classification method.

  14. Electromagnetic design calculation of the control rod drive mechanism

    International Nuclear Information System (INIS)

    Zhu Qirong; Zhu Jingchang

    1991-01-01

    Electromagnetic design calculation of the step-by-step magnetic jacking control rod drive mechanism includes magnetic field force calculation and design calculation of magnetomotive force for three electromagnetic iron and their coilds. The basic principle and method of electromagnetic design calculation had been expounded to take the lift magnet and lift coil for example

  15. Investigation of a mutual interaction force at different pressure amplitudes in sulfuric acid

    International Nuclear Information System (INIS)

    Rezaee, Nastaran; Sadighi-Bonabi, Rasoul; Mirheydari, Mona; Ebrahimi, Homa

    2011-01-01

    This paper investigates the secondary Bjerknes force for two oscillating bubbles in various pressure amplitudes in a concentration of 95% sulfuric acid. The equilibrium radii of the bubbles are assumed to be smaller than 10 μm at a frequency of 37 kHz in various strong driving acoustical fields around 2.0 bars (1 bar=10 5 Pa). The secondary Bjerknes force is investigated in uncoupled and coupled states between the bubbles, with regard to the quasi-adiabatic model for the bubble interior. It finds that the value of the secondary Bjerknes force depends on the driven pressure of sulfuric acid and its amount would be increased by liquid pressure amplitude enhancement. The results show that the repulsion area of the interaction force would be increased by increasing the driven pressure because of nonlinear oscillation of bubbles. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  16. Theoretical Studying the Cyclic Loading of Electric Drive Parts of the Stand duo-160

    Directory of Open Access Journals (Sweden)

    A. A. Maltsev

    2015-01-01

    Full Text Available An electric drive of work rolls of the single-stand rolling mill duo-160 located in the laboratory of Bauman Moscow State Technical University (BMSTU is selected as an object of the theoretical study. After the work rolls have gripped the work-piece the torsional vibrations occur in the drive; a 5-mass dynamic model is built to determine their forms and frequencies. Equations of torsionalvibration movement of masses with time are based on the Lagrange equations of type II. The paper identifies intrinsic moments of inertia and angular stiffness of parts and units of the electric drive. The graphs of the moments of elastic forces are built taking into consideration the dampers and backlashes. A revealed transition process has shown that given amplitudes of the cyclic shear stresses arising in dangerous section of the most loaded top spindle do not exceed the limit of its endurance in this section. In case of excess revealed, it would lead to accumulation of fatigue damage in the spindle metal and to formation of fatigue crack that most probably would appear near the shaft surface rather than in the metal mass. With further using the electric drive this micro-crack would be gradually evolved into macro-crack, the working cross-sectional area of the shaft would be reduced so that there would be a spindle failure and on the surface of a fatigue fracture of its shaft a strongly marked crack growth zone and a completely broken zone would be observed.

  17. Strong Electroweak Symmetry Breaking

    CERN Document Server

    Grinstein, Benjamin

    2011-01-01

    Models of spontaneous breaking of electroweak symmetry by a strong interaction do not have fine tuning/hierarchy problem. They are conceptually elegant and use the only mechanism of spontaneous breaking of a gauge symmetry that is known to occur in nature. The simplest model, minimal technicolor with extended technicolor interactions, is appealing because one can calculate by scaling up from QCD. But it is ruled out on many counts: inappropriately low quark and lepton masses (or excessive FCNC), bad electroweak data fits, light scalar and vector states, etc. However, nature may not choose the minimal model and then we are stuck: except possibly through lattice simulations, we are unable to compute and test the models. In the LHC era it therefore makes sense to abandon specific models (of strong EW breaking) and concentrate on generic features that may indicate discovery. The Technicolor Straw Man is not a model but a parametrized search strategy inspired by a remarkable generic feature of walking technicolor,...

  18. Plasmons in strong superconductors

    International Nuclear Information System (INIS)

    Baldo, M.; Ducoin, C.

    2011-01-01

    We present a study of the possible plasmon excitations that can occur in systems where strong superconductivity is present. In these systems the plasmon energy is comparable to or smaller than the pairing gap. As a prototype of these systems we consider the proton component of Neutron Star matter just below the crust when electron screening is not taken into account. For the realistic case we consider in detail the different aspects of the elementary excitations when the proton, electron components are considered within the Random-Phase Approximation generalized to the superfluid case, while the influence of the neutron component is considered only at qualitative level. Electron screening plays a major role in modifying the proton spectrum and spectral function. At the same time the electron plasmon is strongly modified and damped by the indirect coupling with the superfluid proton component, even at moderately low values of the gap. The excitation spectrum shows the interplay of the different components and their relevance for each excitation modes. The results are relevant for neutrino physics and thermodynamical processes in neutron stars. If electron screening is neglected, the spectral properties of the proton component show some resemblance with the physical situation in high-T c superconductors, and we briefly discuss similarities and differences in this connection. In a general prospect, the results of the study emphasize the role of Coulomb interaction in strong superconductors.

  19. Linear step drive

    International Nuclear Information System (INIS)

    Haniger, L.; Elger, R.; Kocandrle, L.; Zdebor, J.

    1986-01-01

    A linear step drive is described developed in Czechoslovak-Soviet cooperation and intended for driving WWER-1000 control rods. The functional principle is explained of the motor and the mechanical and electrical parts of the drive, power control, and the indicator of position are described. The motor has latches situated in the reactor at a distance of 3 m from magnetic armatures, it has a low structural height above the reactor cover, which suggests its suitability for seismic localities. Its magnetic circuits use counterpoles; the mechanical shocks at the completion of each step are damped using special design features. The position indicator is of a special design and evaluates motor position within ±1% of total travel. A drive diagram and the flow chart of both the control electronics and the position indicator are presented. (author) 4 figs

  20. Fundamentals of electrical drives

    NARCIS (Netherlands)

    Veltman, A.; Pulle, D.W.J.; de Doncker, R.W.

    2016-01-01

    Comprehensive, user-friendly, color illustrated introductory text for electrical drive systems that simplifies the understanding of electrical machine principles Updated edition covers innovations in machine design, power semi-conductors, digital signal processors and simulation software Presents

  1. Science of driving.

    Science.gov (United States)

    2016-08-01

    The Science of Driving project focused on developing a collaborative relationship to develop curriculum units for middle school and high school students to engage them in exciting real-world scenarios. This effort involved faculty, staff, and student...

  2. Drugs and driving

    NARCIS (Netherlands)

    Walsh, J. Michael; De Gier, Johan J.; Christopherson, Asbjørg S.; Verstraete, Alain G.

    The authors present a global overview on the issue of drugs and driving covering four major areas: (1) Epidemiology and Prevalence-which reviews epidemiological research, summarizes available information, discusses the methodological shortcomings of extant studies, and makes recommendations for

  3. Labor Force

    Science.gov (United States)

    Occupational Outlook Quarterly, 2012

    2012-01-01

    The labor force is the number of people ages 16 or older who are either working or looking for work. It does not include active-duty military personnel or the institutionalized population, such as prison inmates. Determining the size of the labor force is a way of determining how big the economy can get. The size of the labor force depends on two…

  4. Factors Driving Business Intelligence Culture

    Directory of Open Access Journals (Sweden)

    Rimvydas Skyrius

    2016-05-01

    Full Text Available The field of business intelligence (BI, despite rapid technology advances, continues to feature inadequate levels of adoption. The attention of researchers is shifting towards hu-man factors of BI adoption. The wide set of human factors influencing BI adoption con-tains elements of what we call BI culture – an overarching concept covering key managerial issues that come up in BI implementation. Research sources provide different sets of features pertaining to BI culture or related concepts – decision-making culture, analytical culture and others. The goal of this paper is to perform the review of research and practical sources to examine driving forces of BI – data-driven approaches, BI agility, maturity and acceptance – to point out culture-related issues that support BI adoption and to suggest an emerging set of factors influencing BI culture.

  5. Otolith shape lends support to the sensory drive hypothesis in rockfishes.

    Science.gov (United States)

    Tuset, V M; Otero-Ferrer, J L; Gómez-Zurita, J; Venerus, L A; Stransky, C; Imondi, R; Orlov, A M; Ye, Z; Santschi, L; Afanasiev, P K; Zhuang, L; Farré, M; Love, M S; Lombarte, A

    2016-10-01

    The sensory drive hypothesis proposes that environmental factors affect both signalling dynamics and the evolution of signals and receivers. Sound detection and equilibrium in marine fishes are senses dependent on the sagittae otoliths, whose morphological variability appears intrinsically linked to the environment. The aim of this study was to understand if and which environmental factors could be conditioning the evolution of this sensory structure, therefore lending support to the sensory drive hypothesis. Thus, we analysed the otolith shape of 42 rockfish species (Sebastes spp.) to test the potential associations with the phylogeny, biological (age), ecological (feeding habit and depth distribution) and biogeographical factors. The results showed strong differences in the otolith shapes of some species, noticeably influenced by ecological and biogeographical factors. Moreover, otolith shape was clearly conditioned by phylogeny, but with a strong environmental effect, cautioning about the use of this structure for the systematics of rockfishes or other marine fishes. However, our most relevant finding is that the data supported the sensory drive hypothesis as a force promoting the radiation of the genus Sebastes. This hypothesis holds that adaptive divergence in communication has significant influence relative to other life history traits. It has already been established in Sebastes for visual characters and organs; our results showed that it applies to otolith transformations as well (despite the clear influence of feeding and depth), expanding the scope of the hypothesis to other sensory structures. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  6. Instant Google Drive starter

    CERN Document Server

    Procopio, Mike

    2013-01-01

    This book is a Starter which teaches you how to use Google Drive practically. This book is perfect for people of all skill levels who want to enjoy the benefits of using Google Drive to safely store their files online and in the cloud. It's also great for anyone looking to learn more about cloud computing in general. Readers are expected to have an Internet connection and basic knowledge of using the internet.

  7. Control rod driving mechanism

    International Nuclear Information System (INIS)

    Ooshima, Yoshio.

    1983-01-01

    Purpose: To perform reliable scram operation, even if abnormality should occur in a system instructing scram operation in FBR type reactors. Constitution: An aluminum alloy member to be melt at a predetermined temperature (about 600sup(o)C) is disposed to a connection part between a control rod and a driving mechanism, whereby the control rod is detached from the driving mechanism and gravitationally fallen to the reactor core. (Ikeda, J.)

  8. Modulated Current Drive Measurements

    International Nuclear Information System (INIS)

    Petty, C.C.; Lohr, J.; Luce, T.C.; Prater, R.; Cox, W.A.; Forest, C.B.; Jayakumar, R.J.; Makowski, M.A.

    2005-01-01

    A new measurement approach is presented which directly determines the noninductive current profile from the periodic response of the motional Stark effect (MSE) signals to the slow modulation of the external current drive source. A Fourier transform of the poloidal magnetic flux diffusion equation is used to analyze the MSE data. An example of this measurement technique is shown using modulated electron cyclotron current drive (ECCD) discharges from the DIII-D tokamak

  9. Belt drive construction improvement

    Directory of Open Access Journals (Sweden)

    I.Yu. Khomenko

    2012-08-01

    Full Text Available The possibility of the traction capacity increase of the belt drive TRK is examined. This was done for the purpose of air conditioning system of passenger car with double-generator system energy supplying. Belts XPC (made by the German firm «Continental ContiTech» testing were conducted. The results confirmed the possibility of their usage in order to improve belt drive TRK characteristics.

  10. Correspondence between Simulator and On-Road Drive Performance: Implications for Assessment of Driving Safety.

    Science.gov (United States)

    Aksan, Nazan; Hacker, Sarah D; Sager, Lauren; Dawson, Jeffrey; Anderson, Steven; Rizzo, Matthew

    2016-03-01

    Forty-two younger (Mean age = 35) and 37 older drivers (Mean age = 77) completed four similar simulated drives. In addition, 32 younger and 30 older drivers completed a standard on-road drive in an instrumented vehicle. Performance in the simulated drives was evaluated using both electronic drive data and video-review of errors. Safety errors during the on-road drive were evaluated by a certified driving instructor blind to simulator performance, using state Department of Transportation criteria. We examined the degree of convergence in performance across the two platforms on various driving tasks including lane change, lane keeping, speed control, stopping, turns, and overall performance. Differences based on age group indicated a pattern of strong relative validity for simulator measures. However, relative rank-order in specific metrics of performance suggested a pattern of moderate relative validity. The findings have implications for the use of simulators in assessments of driving safety as well as its use in training and/or rehabilitation settings.

  11. The effect of ac-driven force on superlubricity in a two-dimensional Frenkel-Kontorova model

    International Nuclear Information System (INIS)

    Lin Maimai

    2010-01-01

    By using the molecular dynamic simulation method with a fourth-order Runge-Kutta algorithm, a two-dimensional dc- and ac-driven Frenkel-Kontorova model with a square symmetry substrate potential for a square lattice layer has been investigated in this paper. For this system, the effects of many different parameters on the static friction force have been studied in detail. It was found that not only the amplitude and frequency of the ac-driven force, but also the direction of dc- and ac-driven forces and the misfit angle between two layers have a strong influence on the static friction force. This indicated that the phenomenon of superlubricity appears easily with larger ac amplitude and smaller ac frequency for some special direction of the external driving force and misfit angle.

  12. Estimation of longitudinal force, lateral vehicle speed and yaw rate for four-wheel independent driven electric vehicles

    Science.gov (United States)

    Chen, Te; Xu, Xing; Chen, Long; Jiang, Haobing; Cai, Yingfeng; Li, Yong

    2018-02-01

    Accurate estimation of longitudinal force, lateral vehicle speed and yaw rate is of great significance to torque allocation and stability control for four-wheel independent driven electric vehicle (4WID-EVs). A fusion method is proposed to estimate the longitudinal force, lateral vehicle speed and yaw rate for 4WID-EVs. The electric driving wheel model (EDWM) is introduced into the longitudinal force estimation, the longitudinal force observer (LFO) is designed firstly based on the adaptive high-order sliding mode observer (HSMO), and the convergence of LFO is analyzed and proved. Based on the estimated longitudinal force, an estimation strategy is then presented in which the strong tracking filter (STF) is used to estimate lateral vehicle speed and yaw rate simultaneously. Finally, co-simulation via Carsim and Matlab/Simulink is carried out to demonstrate the effectiveness of the proposed method. The performance of LFO in practice is verified by the experiment on chassis dynamometer bench.

  13. Self-driving carsickness.

    Science.gov (United States)

    Diels, Cyriel; Bos, Jelte E

    2016-03-01

    This paper discusses the predicted increase in the occurrence and severity of motion sickness in self-driving cars. Self-driving cars have the potential to lead to significant benefits. From the driver's perspective, the direct benefits of this technology are considered increased comfort and productivity. However, we here show that the envisaged scenarios all lead to an increased risk of motion sickness. As such, the benefits this technology is assumed to bring may not be capitalised on, in particular by those already susceptible to motion sickness. This can negatively affect user acceptance and uptake and, in turn, limit the potential socioeconomic benefits that this emerging technology may provide. Following a discussion on the causes of motion sickness in the context of self-driving cars, we present guidelines to steer the design and development of automated vehicle technologies. The aim is to limit or avoid the impact of motion sickness and ultimately promote the uptake of self-driving cars. Attention is also given to less well known consequences of motion sickness, in particular negative aftereffects such as postural instability, and detrimental effects on task performance and how this may impact the use and design of self-driving cars. We conclude that basic perceptual mechanisms need to be considered in the design process whereby self-driving cars cannot simply be thought of as living rooms, offices, or entertainment venues on wheels. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  14. Dementia and driving.

    Science.gov (United States)

    O'Neill, D; Neubauer, K; Boyle, M; Gerrard, J; Surmon, D; Wilcock, G K

    1992-04-01

    Many European countries test cars, but not their drivers, as they age. There is evidence to suggest that human factors are more important than vehicular factors as causes of motor crashes. The elderly also are involved in more accidents per distance travelled than middle-aged drivers. As the UK relies on self-certification of health by drivers over the age of 70 years, we examined the driving practices of patients with dementia attending a Memory Clinic. Nearly one-fifth of 329 patients with documented dementia continued to drive after the onset of dementia, and impaired driving ability was noted in two-thirds of these. Their families experienced great difficulty in persuading patients to stop driving, and had to invoke outside help in many cases. Neuropsychological tests did not help to identify those who drove badly while activity of daily living scores were related to driving ability. These findings suggest that many patients with dementia drive in an unsafe fashion after the onset of the illness. The present system of self-certification of health by the elderly for driver-licensing purposes needs to be reassessed.

  15. VEHICLE DRIVING CYCLE OPTIMISATION ON THE HIGHWAY

    Directory of Open Access Journals (Sweden)

    Zinoviy STOTSKO

    2016-06-01

    Full Text Available This paper is devoted to the problem of reducing vehicle energy consumption. The authors consider the optimisation of highway driving cycle a way to use the kinetic energy of a car more effectively at various road conditions. The model of a vehicle driving control at the highway which consists of elementary cycles, such as accelerating, free rolling and deceleration under forces of external resistance, was designed. Braking, as an energy dissipation regime, was not included. The influence of the various longitudinal profiles of the road was taken into consideration and included in the model. Ways to use the results of monitoring road and traffic conditions are presented. The method of non-linear programming is used to design the optimal vehicle control function and phase trajectory. The results are presented by improved typical driving cycles that present energy saving as a subject of choice at a specified schedule.

  16. Linear Motor for Drive of Belt Conveyor

    Directory of Open Access Journals (Sweden)

    Milan Krasl

    2006-01-01

    Full Text Available This paper introduces a novel approach on the design of a linear motor for drive of belt conveyor (LMBC. The motor is a simple combination of asynchronous motor in plane. The electromagnetic forces is one of the most important parameters of electrical machines. This parameter is necessary for the checking of the design. This paper describes several variants: linear motor with slots in platens, slots in one half of platens and optimization of slots. The electromagnetic force can be found with the help of a Finite Elements Method – based program. For solution was used QuickField program.

  17. Dispersion Forces

    CERN Document Server

    Buhmann, Stefan Yoshi

    2012-01-01

    In this book, a modern unified theory of dispersion forces on atoms and bodies is presented which covers a broad range of advanced aspects and scenarios. Macroscopic quantum electrodynamics is shown to provide a powerful framework for dispersion forces which allows for discussing general properties like their non-additivity and the relation between microscopic and macroscopic interactions. It is demonstrated how the general results can be used to obtain dispersion forces on atoms in the presence of bodies of various shapes and materials. Starting with a brief recapitulation of volume I, this volume II deals especially with bodies of irregular shapes, universal scaling laws, dynamical forces on excited atoms, enhanced forces in cavity quantum electrodynamics, non-equilibrium forces in thermal environments and quantum friction. The book gives both the specialist and those new to the field a thorough overview over recent results in the field. It provides a toolbox for studying dispersion forces in various contex...

  18. Factors driving the spatial layout of distribution channels

    NARCIS (Netherlands)

    Onstein, A.T.C.; Ektesaby, M.; Rezaei, J.; Tavasszy, L.A.; van Damme, D.A.

    2017-01-01

    Research statement Our study analyses the factors that drive decision-making on distribution structures, including the layout of distribution channels and the locations of distribution centres. Distribution is a primary firm activity, which strongly influences logistics costs and logistics

  19. Strongly intensive quantities

    International Nuclear Information System (INIS)

    Gorenstein, M. I.; Gazdzicki, M.

    2011-01-01

    Analysis of fluctuations of hadron production properties in collisions of relativistic particles profits from use of measurable intensive quantities which are independent of system size variations. The first family of such quantities was proposed in 1992; another is introduced in this paper. Furthermore we present a proof of independence of volume fluctuations for quantities from both families within the framework of the grand canonical ensemble. These quantities are referred to as strongly intensive ones. Influence of conservation laws and resonance decays is also discussed.

  20. Strong-coupling approximations

    International Nuclear Information System (INIS)

    Abbott, R.B.

    1984-03-01

    Standard path-integral techniques such as instanton calculations give good answers for weak-coupling problems, but become unreliable for strong-coupling. Here we consider a method of replacing the original potential by a suitably chosen harmonic oscillator potential. Physically this is motivated by the fact that potential barriers below the level of the ground-state energy of a quantum-mechanical system have little effect. Numerically, results are good, both for quantum-mechanical problems and for massive phi 4 field theory in 1 + 1 dimensions. 9 references, 6 figures

  1. INFLUENCE OF MOBILE PHONE USE WHILE DRIVING

    Directory of Open Access Journals (Sweden)

    T. Hugh WOO, Ph.D., P.E.

    2001-01-01

    Based on the conclusions of this study, the Legislative Yuan of Taiwan passed a law to ban the use of handheld mobile phones while driving in January 2, 2001. For a compulsory three-month campaign, the regulation will be in force from September 1, with a violation fine of NT$3,000 (approximate to US$90 for drivers and NT$1,000 for motorcyclists.

  2. Base drive for paralleled inverter systems

    Science.gov (United States)

    Nagano, S. (Inventor)

    1980-01-01

    In a paralleled inverter system, a positive feedback current derived from the total current from all of the modules of the inverter system is applied to the base drive of each of the power transistors of all modules, thereby to provide all modules protection against open or short circuit faults occurring in any of the modules, and force equal current sharing among the modules during turn on of the power transistors.

  3. Topographic changes and their driving factors after 2008 Wenchuan Earthquake

    Science.gov (United States)

    Li, C.; Wang, M.; Xie, J.; Liu, K.

    2017-12-01

    The Wenchuan Ms 8.0 Earthquake caused topographic change in the stricken areas because of the formation of numerous coseismic landslides. The emergence of new landslides and debris flows and movement of loose materials under the driving force of heavy rainfall could further shape the local topography. Dynamic topographic changes in mountainous areas stricken by major earthquakes have a strong linkage to the development and occurrence of secondary disasters. However, little attention has been paid to continuously monitoring mountain environment change after such earthquakes. A digital elevation model (DEM) is the main feature of the terrain surface, in our research, we extracted DEM in 2013 and 2015 of a typical mountainous area severely impacted by the 2008 Wenchuan earthquake from the ZY-3 stereo pair images with validation by field measurement. Combined with the elevation dataset in 2002 and 2010, we quantitatively assessed elevation changes in different years and qualitatively analyzed spatiotemporal variation of the terrain and mass movement across the study area. The results show that the earthquake stricken area experienced substantial elevation changes caused by seismic forces and subsequent rainfalls. Meanwhile, deposits after the earthquake are mainly accumulated on the river-channels and mountain ridges and deep gullies which increase the risk of other geo-hazards. And the heavy rainfalls after the earthquake have become the biggest driver of elevation reduction, which overwhelmed elevation increase during the major earthquake. Our study provided a better understanding of subsequent hazards and risks faced by residents and communities stricken by major earthquakes.

  4. Strongly disordered superconductors

    International Nuclear Information System (INIS)

    Muttalib, K.A.

    1982-01-01

    We examine some universal effects of strong non-magnetic disorder on the electron-phonon and electron-electron interactions in a superconductor. In particular we explicitly take into account the effect of slow diffusion of electrons in a disordered medium by working in an exact impurity eigenstate representation. We find that the normal diffusion of electrons characterized by a constant diffusion coefficient does not lead to any significant correction to the electron-phonon or the effective electron-electron interactions in a superconductor. We then consider sufficiently strong disorder where Anderson localization of electrons becomes important and determine the effect of localization on the electron-electron interactions. We find that due to localization, the diffusion of electrons becomes anomalous in the sense that the diffusion coefficient becomes scale dependent. This results in an increase in the effective electron-electron interaction with increasing disorder. We propose that this provides a natural explanation for the unusual sensitivity of the transition temperature T/sub c/ of the high T/sub c/ superconductors (T/sub c/ > 10 0 K) to damage effects

  5. Strong Coupling Holography

    CERN Document Server

    Dvali, Gia

    2009-01-01

    We show that whenever a 4-dimensional theory with N particle species emerges as a consistent low energy description of a 3-brane embedded in an asymptotically-flat (4+d)-dimensional space, the holographic scale of high-dimensional gravity sets the strong coupling scale of the 4D theory. This connection persists in the limit in which gravity can be consistently decoupled. We demonstrate this effect for orbifold planes, as well as for the solitonic branes and string theoretic D-branes. In all cases the emergence of a 4D strong coupling scale from bulk holography is a persistent phenomenon. The effect turns out to be insensitive even to such extreme deformations of the brane action that seemingly shield 4D theory from the bulk gravity effects. A well understood example of such deformation is given by large 4D Einstein term in the 3-brane action, which is known to suppress the strength of 5D gravity at short distances and change the 5D Newton's law into the four-dimensional one. Nevertheless, we observe that the ...

  6. Principle and analysis of a linear motor driving system for HTS levitation applications

    International Nuclear Information System (INIS)

    Jin, Jian X.; Guo, You G.; Zhu, Jian G.

    2007-01-01

    High temperature superconductor (HTS) high levitation force density with passive and self-stabilizing features allows a number of special applications to be developed. Linear motor driving systems are commonly required for those applications such as levitated transport systems. In this paper a prototype linear motor driving system with HTS is analyzed with calculation details including its magnetic fields and driving forces presented in the paper

  7. Neuromorphic meets neuromechanics, part II: the role of fusimotor drive

    Science.gov (United States)

    Jalaleddini, Kian; Minos Niu, Chuanxin; Chakravarthi Raja, Suraj; Sohn, Won Joon; Loeb, Gerald E.; Sanger, Terence D.; Valero-Cuevas, Francisco J.

    2017-04-01

    Objective. We studied the fundamentals of muscle afferentation by building a Neuro-mechano-morphic system actuating a cadaveric finger. This system is a faithful implementation of the stretch reflex circuitry. It allowed the systematic exploration of the effects of different fusimotor drives to the muscle spindle on the closed-loop stretch reflex response. Approach. As in Part I of this work, sensory neurons conveyed proprioceptive information from muscle spindles (with static and dynamic fusimotor drive) to populations of α-motor neurons (with recruitment and rate coding properties). The motor commands were transformed into tendon forces by a Hill-type muscle model (with activation-contraction dynamics) via brushless DC motors. Two independent afferented muscles emulated the forces of flexor digitorum profundus and the extensor indicis proprius muscles, forming an antagonist pair at the metacarpophalangeal joint of a cadaveric index finger. We measured the physical response to repetitions of bi-directional ramp-and-hold rotational perturbations for 81 combinations of static and dynamic fusimotor drives, across four ramp velocities, and three levels of constant cortical drive to the α-motor neuron pool. Main results. We found that this system produced responses compatible with the physiological literature. Fusimotor and cortical drives had nonlinear effects on the reflex forces. In particular, only cortical drive affected the sensitivity of reflex forces to static fusimotor drive. In contrast, both static fusimotor and cortical drives reduced the sensitivity to dynamic fusimotor drive. Interestingly, realistic signal-dependent motor noise emerged naturally in our system without having been explicitly modeled. Significance. We demonstrate that these fundamental features of spinal afferentation sufficed to produce muscle function. As such, our Neuro-mechano-morphic system is a viable platform to study the spinal mechanisms for healthy muscle function—and its

  8. Control rod drives

    International Nuclear Information System (INIS)

    Hayakawa, Hiroyasu.

    1979-01-01

    Purpose: To enable rapid control in a simple circuit by providing a motor control device having an electric capacity capable of simultaneously driving all of the control rods rapidly only in the inserting direction as well as a motor controlling device capable of fine control for the insertion and extraction at usual operation. Constitution: The control rod drives comprise a first motor control device capable of finely controlling the control rods both in inserting and extracting directions, a second motor control device capable of rapidly driving the control rods only in the inserting direction, and a first motor switching circuit and a second motor switching circuit switched by switches. Upon issue of a rapid insertion instruction for the control rods, the second motor switching circuit is closed by the switch and the second motor control circuit and driving motors are connected. Thus, each of the control rod driving motors is driven at a high speed in the inserting direction to rapidly insert all of the control rods. (Yoshino, Y.)

  9. Epilepsy and driving

    Directory of Open Access Journals (Sweden)

    Matej Mavrič

    2015-05-01

    Full Text Available Epilepsy poses a risk for all participants in road traffic; therefore people with epilepsy do not meet the criteria for an unlimited driving license. Their driving is affected not only by epileptic seizures causing impaired consciousness and involuntary movements, but also by antiepileptic drugs with their many unwanted affects. The experts have not yet agreed on whether people with epilepsy have an increased risk of experiencing a road traffic accident. However, recent data suggests that the overall risk is lower compared to other medical conditions. Scientific evidence forms the basis of legislation, which by limiting people with epilepsy, enables all participants in road traffic to drive in the safest possible environment. The legislation that governs epilepsy and driving in Slovenia has been recently thoroughly reformed and thus allows a less discriminatory management of people with epilepsy. Although people with epilepsy experience many issues in their daily life, including their personal relationships and employment, they often list the need for driving as a top concern in surveys. General physicians play an important role in managing the issues of people with epilepsy.

  10. Self-rated Driving and Driving Safety in Older Adults

    OpenAIRE

    Ross, Lesley A.; Dodson, Joan; Edwards, Jerri D.; Ackerman, Michelle L.; Ball, Karlene

    2012-01-01

    Many U.S. states rely on older adults to self-regulate their driving and determine when driving is no longer a safe option. However, the relationship of older adults’ self-rated driving in terms of actual driving competency outcomes is unclear. The current study investigates self-rated driving in terms of (1) systematic differences between older adults with high (good/excellent) versus low (poor/fair/average) self-ratings, and (2) the predictive nature of self-rated driving to adverse driving...

  11. LIGO: The strong belief

    CERN Multimedia

    Antonella Del Rosso

    2016-01-01

    Twenty years of designing, building and testing a number of innovative technologies, with the strong belief that the endeavour would lead to a historic breakthrough. The Bulletin publishes an abstract of the Courier’s interview with Barry Barish, one of the founding fathers of LIGO.   The plots show the signals of gravitational waves detected by the twin LIGO observatories at Livingston, Louisiana, and Hanford, Washington. (Image: Caltech/MIT/LIGO Lab) On 11 February, the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo collaborations published a historic paper in which they showed a gravitational signal emitted by the merger of two black holes. These results come after 20 years of hard work by a large collaboration of scientists operating the two LIGO observatories in the US. Barry Barish, Linde Professor of Physics, Emeritus at the California Institute of Technology and former Director of the Global Design Effort for the Internat...

  12. Strongly interacting Higgs bosons

    International Nuclear Information System (INIS)

    Appelquist, T.; Bernard, C.

    1980-01-01

    The sensitivity of present-energy weak interactions to a strongly interacting heavy-Higgs-boson sector is discussed. The gauged nonlinear sigma model, which is the limit of the linear model as the Higgs-boson mass goes to infinity, is used to organize and catalogue all possible heavy-Higgs-boson effects. As long as the SU(2)/sub L/ x SU(2)/sub R/ symmetry of the Higgs sector is preserved, these effects are found to be small, of the order of the square of the gauge coupling times logarithms (but not powers) of the Higgs-boson mass divided by the W mass. We work in the context of a simplified model with gauge group SU(2)/sub L/; the extension to SU(2)/sub L/ x U(1) is briefly discussed

  13. Strong field interaction of laser radiation

    International Nuclear Information System (INIS)

    Pukhov, Alexander

    2003-01-01

    The Review covers recent progress in laser-matter interaction at intensities above 10 18 W cm -2 . At these intensities electrons swing in the laser pulse with relativistic energies. The laser electric field is already much stronger than the atomic fields, and any material is instantaneously ionized, creating plasma. The physics of relativistic laser-plasma is highly non-linear and kinetic. The best numerical tools applicable here are particle-in-cell (PIC) codes, which provide the most fundamental plasma model as an ensemble of charged particles. The three-dimensional (3D) PIC code Virtual Laser-Plasma Laboratory runs on a massively parallel computer tracking trajectories of up to 10 9 particles simultaneously. This allows one to simulate real laser-plasma experiments for the first time. When the relativistically intense laser pulses propagate through plasma, a bunch of new physical effects appears. The laser pulses are subject to relativistic self-channelling and filamentation. The gigabar ponderomotive pressure of the laser pulse drives strong currents of plasma electrons in the laser propagation direction; these currents reach the Alfven limit and generate 100 MG quasistatic magnetic fields. These magnetic fields, in turn, lead to the mutual filament attraction and super-channel formation. The electrons in the channels are accelerated up to gigaelectronvolt energies and the ions gain multi-MeV energies. We discuss different mechanisms of particle acceleration and compare numerical simulations with experimental data. One of the very important applications of the relativistically strong laser beams is the fast ignition (FI) concept for the inertial fusion energy (IFE). Petawatt-class lasers may provide enough energy to isochorically ignite a pre-compressed target consisting of thermonuclear fuel. The FI approach would ease dramatically the constraints on the implosion symmetry and improve the energy gain. However, there is a set of problems to solve before the FI

  14. Software Process Improvement Using Force Field Analysis ...

    African Journals Online (AJOL)

    An improvement plan is then drawn and implemented. This paper studied the state of Nigerian software development organizations based on selected attributes. Force field analysis is used to partition the factors obtained into driving and restraining forces. An attempt was made to improve the software development process ...

  15. Strong piezoelectricity in bioinspired peptide nanotubes.

    Science.gov (United States)

    Kholkin, Andrei; Amdursky, Nadav; Bdikin, Igor; Gazit, Ehud; Rosenman, Gil

    2010-02-23

    We show anomalously strong shear piezoelectric activity in self-assembled diphenylalanine peptide nanotubes (PNTs), indicating electric polarization directed along the tube axis. Comparison with well-known piezoelectric LiNbO(3) and lateral signal calibration yields sufficiently high effective piezoelectric coefficient values of at least 60 pm/V (shear response for tubes of approximately 200 nm in diameter). PNTs demonstrate linear deformation without irreversible degradation in a broad range of driving voltages. The results open up a wide avenue for developing new generations of "green" piezoelectric materials and piezonanodevices based on bioactive tubular nanostructures potentially compatible with human tissue.

  16. Gears and gear drives

    CERN Document Server

    Jelaska, Damir T

    2012-01-01

    Understanding how gears are formed and how they interact or 'mesh' with each other is essential when designing equipment that uses gears or gear trains. The way in which gear teeth are formed and how they mesh is determined by their geometry and kinematics, which is the topic of this book.  Gears and Gear Drives provides the reader with comprehensive coverage of gears and gear drives. Spur, helical, bevel, worm and planetary gears are all covered, with consideration given to their classification, geometry, kinematics, accuracy control, load capacity and manufacturing. Cylindric

  17. Toyota hybrid synergy drive

    Energy Technology Data Exchange (ETDEWEB)

    Gautschi, H.

    2008-07-01

    This presentation made at the Swiss 2008 research conference on traffic by Hannes Gautschi, director of service and training at the Toyota company in Switzerland, takes a look at Toyota's hybrid drive vehicles. The construction of the vehicles and their combined combustion engines and electric generators and drives is presented and the combined operation of these components is described. Braking and energy recovery are discussed. Figures on the performance, fuel consumption and CO{sub 2} output of the hybrid vehicles are compared with those of conventional vehicles.

  18. John Strong - 1941-2006

    CERN Multimedia

    2006-01-01

    Our friend and colleague John Strong was cruelly taken from us by a brain tumour on 31 July, a few days before his 65th birthday. John started his career and obtained his PhD in a group from Westfield College, initially working on experiments at Rutherford Appleton Laboratory (RAL). From the early 1970s onwards, however, his research was focused on experiments in CERN, with several particularly notable contributions. The Omega spectrometer adopted a system John had originally developed for experiments at RAL using vidicon cameras (a type of television camera) to record the sparks in the spark chambers. This highly automated system allowed Omega to be used in a similar way to bubble chambers. He contributed to the success of NA1 and NA7, where he became heavily involved in the electronic trigger systems. In these experiments the Westfield group joined forces with Italian colleagues to measure the form factors of the pion and the kaon, and the lifetime of some of the newly discovered charm particles. Such h...

  19. Remnants of strong tidal interactions

    International Nuclear Information System (INIS)

    Mcglynn, T.A.

    1990-01-01

    This paper examines the properties of stellar systems that have recently undergone a strong tidal shock, i.e., a shock which removes a significant fraction of the particles in the system, and where the shocked system has a much smaller mass than the producer of the tidal field. N-body calculations of King models shocked in a variety of ways are performed, and the consequences of the shocks are investigated. The results confirm the prediction of Jaffe for shocked systems. Several models are also run where the tidal forces on the system are constant, simulating a circular orbit around a primary, and the development of tidal radii under these static conditions appears to be a mild process which does not dramatically affect material that is not stripped. The tidal radii are about twice as large as classical formulas would predict. Remnant density profiles are compared with a sample of elliptical galaxies, and the implications of the results for the development of stellar populations and galaxies are considered. 38 refs

  20. Understanding adolescent development: implications for driving safety.

    Science.gov (United States)

    Keating, Daniel P

    2007-01-01

    The implementation of Graduated Driver Licensing (GDL) programs has significantly improved the crash and fatality rates of novice teen drivers, but these rates remain unacceptably high. A review of adolescent development research was undertaken to identify potential areas of improvement. Research support for GDL was found to be strong, particularly regarding early acquisition of expertise in driving safety (beyond driving skill), and to limitations that reduce opportunities for distraction. GDL regimes are highly variable, and no US jurisdictions have implemented optimal regimes. Expanding and improving GDL to enhance acquisition of expertise and self-regulation are indicated for implementation and for applied research. Driver training that effectively incorporates safety goals along with driving skill is another target. The insurance industry will benefit from further GDL enhancements. Benefits may accrue to improved driver training, improved simulation devices during training, and automated safety feedback instrumentation.

  1. Smooth driving of Moessbauer electromechanical transducers

    Energy Technology Data Exchange (ETDEWEB)

    Veiga, A., E-mail: veiga@fisica.unlp.edu.ar; Mayosky, M. A. [Universidad Nacional de La Plata, Facultad de Ingenieria (Argentina); Martinez, N.; Mendoza Zelis, P.; Pasquevich, G. A.; Sanchez, F. H. [Instituto de Fisica La Plata, CONICET (Argentina)

    2011-11-15

    Quality of Moessbauer spectra is strongly related to the performance of source velocity modulator. Traditional electromechanical driving techniques demand hard-edged square or triangular velocity waveforms that introduce long settling times and demand careful driver tuning. For this work, the behavior of commercial velocity transducers and drive units was studied under different working conditions. Different velocity reference waveforms in constant-acceleration, constant-velocity and programmable-velocity techniques were tested. Significant improvement in spectrometer efficiency and accuracy was achieved by replacing triangular and square hard edges with continuous smooth-shaped transitions. A criterion for best waveform selection and synchronization is presented and attainable enhancements are evaluated. In order to fully exploit this driving technique, a compact microprocessor-based architecture is proposed and a suitable data acquisition system implementation is presented. System linearity and efficiency characterization are also shown.

  2. Strong-interaction nonuniversality

    International Nuclear Information System (INIS)

    Volkas, R.R.; Foot, R.; He, X.; Joshi, G.C.

    1989-01-01

    The universal QCD color theory is extended to an SU(3) 1 direct product SU(3) 2 direct product SU(3) 3 gauge theory, where quarks of the ith generation transform as triplets under SU(3)/sub i/ and singlets under the other two factors. The usual color group is then identified with the diagonal subgroup, which remains exact after symmetry breaking. The gauge bosons associated with the 16 broken generators then form two massive octets under ordinary color. The interactions between quarks and these heavy gluonlike particles are explicitly nonuniversal and thus an exploration of their physical implications allows us to shed light on the fundamental issue of strong-interaction universality. Nonuniversality and weak flavor mixing are shown to generate heavy-gluon-induced flavor-changing neutral currents. The phenomenology of these processes is studied, as they provide the major experimental constraint on the extended theory. Three symmetry-breaking scenarios are presented. The first has color breaking occurring at the weak scale, while the second and third divorce the two scales. The third model has the interesting feature of radiatively induced off-diagonal Kobayashi-Maskawa matrix elements

  3. John Strong (1941 - 2006)

    CERN Multimedia

    Wickens, F

    Our friend and colleague John Strong was cruelly taken from us by a brain tumour on Monday 31st July, a few days before his 65th birthday John started his career working with a group from Westfield College, under the leadership of Ted Bellamy. He obtained his PhD and spent the early part of his career on experiments at Rutherford Appleton Laboratory (RAL), but after the early 1970s his research was focussed on experiments in CERN. Over the years he made a number of notable contributions to experiments in CERN: The Omega spectrometer adopted a system John had originally developed for experiments at RAL using vidicon cameras to record the sparks in the spark chambers; He contributed to the success of NA1 and NA7, where he became heavily involved in the electronic trigger systems; He was responsible for the second level trigger system for the ALEPH detector and spent five years leading a team that designed and built the system, which ran for twelve years with only minor interventions. Following ALEPH he tur...

  4. Different forces

    CERN Multimedia

    1982-01-01

    The different forces, together with a pictorial analogy of how the exchange of particles works. The table lists the relative strength of the couplings, the quanta associated with the force fields and the bodies or phenomena in which they have a dominant role.

  5. Labor Force

    Science.gov (United States)

    Occupational Outlook Quarterly, 2010

    2010-01-01

    The labor force is the number of people aged 16 or older who are either working or looking for work. It does not include active-duty military personnel or institutionalized people, such as prison inmates. Quantifying this total supply of labor is a way of determining how big the economy can get. Labor force participation rates vary significantly…

  6. Comparing Expert and Novice Driving Behavior in a Driving Simulator

    Directory of Open Access Journals (Sweden)

    Hiran B. Ekanayake

    2014-02-01

    Full Text Available This paper presents a study focused on comparing driving behavior of expert and novice drivers in a mid-range driving simulator with the intention of evaluating the validity of driving simulators for driver training. For the investigation, measurements of performance, psychophysiological measurements, and self-reported user experience under different conditions of driving tracks and driving sessions were analyzed. We calculated correlations between quantitative and qualitative measures to enhance the reliability of the findings. The experiment was conducted involving 14 experienced drivers and 17 novice drivers. The results indicate that driving behaviors of expert and novice drivers differ from each other in several ways but it heavily depends on the characteristics of the task. Moreover, our belief is that the analytical framework proposed in this paper can be used as a tool for selecting appropriate driving tasks as well as for evaluating driving performance in driving simulators.

  7. Oscillating field current drive for reversed field pinch discharges

    International Nuclear Information System (INIS)

    Schoenberg, K.F.; Gribble, R.F.; Baker, D.A.

    1984-06-01

    Oscillating Field Current Drive (OFCD), also known as F-THETA pumping, is a steady-state current-drive technique proposed for the Reversed Field Pinch (RFP). Unlike other current-drive techniques, which employ high-technology, invasive, and power intensive schemes using radio frequency or neutral particle injection, F-THETA pumping entails driving the toroidal and poloidal magnetic field circuits with low-frequency (audio) oscillating voltage sources. Current drive by this technique is a consequence of the strong nonlinear plasma coupling in the RFP. Because of its low frequency and efficient plasma coupling, F-THETA pumping shows excellent promise as a reactor-relevant current-drive technique. A conceptual and computational study of this concept, including its experimental and reactor relevance, is explored in this paper

  8. Driving skills after whiplash.

    Science.gov (United States)

    Gimse, R; Bjørgen, I A; Straume, A

    1997-09-01

    Previous studies have shown that some persons with longlasting problems after whiplash have changed eye movements. These changes have been related to disturbance of the posture control system. The question raised in the present study is whether such disturbances can influence daily life functions connected with balance, position and external movements, such as car driving. A group of 23 persons with disturbed eye movements due to whiplash injury, was tested in a driving simulator, together with a closely matched control group. The results revealed significant differences between the two groups with respect to response times to the traffic signs presented, identification of type of sign, as well as steering precision while the subjects' attention was directed to the process of identifying the signs. Alternative explanations such as driving experience, pain, medication or malingering are at least partly controlled for, but cannot completely be ruled out. A distorted posture control system leading to disturbance of eye movements seems to be the most likely primary causative factor, but these disturbances are most certainly complexly determined. Reduced attention capacity is considered to be a mediating secondary factor. Registration of eye movements may be a useful diagnostic tool to evaluate driving skill after whiplash.

  9. Gaze-controlled Driving

    DEFF Research Database (Denmark)

    Tall, Martin; Alapetite, Alexandre; San Agustin, Javier

    2009-01-01

    We investigate if the gaze (point of regard) can control a remote vehicle driving on a racing track. Five different input devices (on-screen buttons, mouse-pointing low-cost webcam eye tracker and two commercial eye tracking systems) provide heading and speed control on the scene view transmitted...

  10. Gas turbine drives

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    Developments in gas turbine drives are reviewed, e.g., low weight per unit power and thrust-weight ratio, fast availability of the maximum speed, absolute resistance to cold and to droplet formation vibrationeless run, and low exhaust gas temperatures. Applications in aeronautic engineering (turbofan), power stations, marine propulsion systems, railways and road transportation vehicles are mentioned.

  11. Chaos in drive systems

    Directory of Open Access Journals (Sweden)

    Kratochvíl C.

    2007-10-01

    Full Text Available The purpose of this article is to provide an elementary introduction to the subject of chaos in the electromechanical drive systems. In this article, we explore chaotic solutions of maps and continuous time systems. These solutions are also bounded like equilibrium, periodic and quasiperiodic solutions.

  12. Electric Drive Study

    Science.gov (United States)

    1987-03-01

    compound promises to reduce weight of future permanent magnet motors by 20 to 30 percent; a similar reduction is expected in size (approximately 20...drive systems. The AC permanent magnet (brushless DC motor) is rapidly evolving and will replace most electrically excited machines. Permanent magnet motors using

  13. Electric-Drive Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Septon, Kendall K [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-11

    Electric-drive vehicles use electricity as their primary fuel or to improve the efficiency of conventional vehicle designs. These vehicles can be divided into three categories: Hybrid electric vehicles (HEVs), Plug-in hybrid electric vehicles (PHEVs), All-electric vehicles (EVs). Together, PHEVs and EVs can also be referred to as plug-in electric vehicles (PEVs).

  14. Electric-Drive Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-09-01

    Electric-drive vehicles use electricity as their primary fuel or to improve the efficiency of conventional vehicle designs. These vehicles can be divided into three categories: Hybrid electric vehicles (HEVs), Plug-in hybrid electric vehicles (PHEVs), All-electric vehicles (EVs). Together, PHEVs and EVs can also be referred to as plug-in electric vehicles (PEVs).

  15. Driving While Intoxicated.

    Science.gov (United States)

    Brick, John

    Alcohol intoxication increases the risk of highway accidents, the relative risk of crash probability increasing as a function of blood alcohol content (BAC). Because alcohol use is more prevalent than use of other drugs, more is known about the relationship between alcohol use and driving. Most states presume a BAC of .10% to be evidence of drunk…

  16. Impulsivity-like traits and risky driving behaviors among college students.

    Science.gov (United States)

    Pearson, Matthew R; Murphy, Elaine M; Doane, Ashley N

    2013-04-01

    The present study examined the predictive effects of five impulsivity-like traits (Premeditation, Perseverance, Sensation Seeking, Negative Urgency, and Positive Urgency) on driving outcomes (driving errors, driving lapses, driving violations, cell phone driving, traffic citations, and traffic collisions). With a convenience sample of 266 college student drivers, we found that each of the impulsivity-like traits was related to multiple risky driving outcomes. Positive Urgency (tendency to act impulsively when experiencing negative affect) was the most robust predictor of risky driving outcomes. Positive Urgency is a relatively newly conceptualized impulsivity-like trait that was not examined in the driving literature previously, suggesting a strong need to further examine its role as a personality trait related to risky driving. These findings generally support the multidimensional assessment of impulsivity-like traits, and they specifically support the addition of Positive Urgency to a list of risk factors for risky driving behaviors. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Nonlinear nonresonant forces by radio-frequency waves in plasmas

    International Nuclear Information System (INIS)

    Gao Zhe; Fisch, Nathaniel J.; Qin, Hong; Myra, J. R.

    2007-01-01

    Nonresonant forces by applied rf waves in plasmas are analyzed. Along the background dc magnetic field, the force arises from the gradient of the ponderomotive potential. Only when the dc magnetic field is straight, however, is this parallel force completely consistent with that from the single particle picture, where the ponderomotive force depends on the gradients of rf fields only. Across the dc magnetic field, besides the ponderomotive force from the particle picture, additional Reynolds stress and polarization stress contribute to the total force. For waves with frequency much lower than the cyclotron frequency, the perpendicular forces from the particle and fluid pictures can have opposite signs. In plasmas with a symmetry angle (e.g., toroidal systems), nonresonant forces cannot drive net flow or current in the flux surface, but the radial force may influence macroscopic behavior of plasma. Moreover, nonresonant forces may drive flow or current in linear plasmas or in a localized region of toroidal plasmas

  18. Rod drive and latching mechanism

    International Nuclear Information System (INIS)

    Veronesi, L.; Sherwood, D.G.

    1982-01-01

    Hydraulic drive and latching mechanisms for driving reactivity control mechanisms in nuclear reactors are described. Preferably, the pressurized reactor coolant is utilized to raise the drive rod into contact with and to pivot the latching mechanism so as to allow the drive rod to pass the latching mechanism. The pressure in the housing may then be equalized which allows the drive rod to move downwardly into contact with the latching mechanism but to hold the shaft in a raised position with respect to the reactor core. Once again, the reactor coolant pressure may be utilized to raise the drive rod and thus pivot the latching mechanism so that the drive rod passes above the latching mechanism. Again, the mechanism pressure can be equalized which allows the drive rod to fall and pass by the latching mechanism so that the drive rod approaches the reactor core. (author)

  19. Fundamental limitations on 'warp drive' spacetimes

    International Nuclear Information System (INIS)

    Lobo, Francisco S N; Visser, Matt

    2004-01-01

    'Warp drive' spacetimes are useful as 'gedanken-experiments' that force us to confront the foundations of general relativity, and among other things, to precisely formulate the notion of 'superluminal' communication. After carefully formulating the Alcubierre and Natario warp drive spacetimes, and verifying their non-perturbative violation of the classical energy conditions, we consider a more modest question and apply linearized gravity to the weak-field warp drive, testing the energy conditions to first and second orders of the warp-bubble velocity, v. Since we take the warp-bubble velocity to be non-relativistic, v << c, we are not primarily interested in the 'superluminal' features of the warp drive. Instead we focus on a secondary feature of the warp drive that has not previously been remarked upon-the warp drive (if it could be built) would be an example of a 'reaction-less drive'. For both the Alcubierre and Natario warp drives we find that the occurrence of significant energy condition violations is not just a high-speed effect, but that the violations persist even at arbitrarily low speeds. A particularly interesting feature of this construction is that it is now meaningful to think of placing a finite mass spaceship at the centre of the warp bubble, and then see how the energy in the warp field compares with the mass-energy of the spaceship. There is no hope of doing this in Alcubierre's original version of the warp field, since by definition the point at the centre of the warp bubble moves on a geodesic and is 'massless'. That is, in Alcubierre's original formalism and in the Natario formalism the spaceship is always treated as a test particle, while in the linearized theory we can treat the spaceship as a finite mass object. For both the Alcubierre and Natario warp drives we find that even at low speeds the net (negative) energy stored in the warp fields must be a significant fraction of the mass of the spaceship

  20. New active machine tool drive mounting on the frame

    Directory of Open Access Journals (Sweden)

    Švéda J.

    2007-10-01

    Full Text Available The paper deals with the new active mounting of the machine tool drives. The commonly used machine tools are at this time mainly equipped with fix-mounting of the feed drives. This structure causes full transmission of the force shocks to the machine bed and thereby restricts the dynamic properties of the motion axis and the whole machine. The spring-mounting of the feed drives is one of the possibilities how to partially suppress the vibrations. The force that reacts to the machine tool bed is transformed thereby the vibrations are lightly reduced. Unfortunately the transformation is not fully controlled. The new active mounting of the machine tool drives allows to fully control the force behaviour that react to the machine body. Thereby the number of excited frequencies on the machine tool bed is significantly reduced. The active variant of the feed drive mounting is characterized by the synergistic cooperation between two series-connected actuators (“motor on motor”. The paper briefly describes design, control techniques and optimization of the feed drives with the new active mounting conception.

  1. Are women the next driving force in mining?

    Energy Technology Data Exchange (ETDEWEB)

    Perry, J.

    2007-07-15

    A symposium entitled 'Women in mining' was held as part of Australia's Minerals Week 2007, on 29 May in Canberra, ACT. In July 2007, Engineers Australia together with Association of Professional Engineers Scientists and Managers, Australia held a women's conference in Melbourne. A survey carried out identified the two main obstacles to women's career advancement: balancing work and life, followed by workplace culture. The majority of female respondents of a recent survey by the Australian Institute of Mining and Metallurgy were concentrated around the early to intermediate stages of their career whereas male respondents were clustered around senior positions. These findings are in line with a report commissioned by the mineral industry and the federal government 'Unearthing new resources: attracting and retaining women in the Australian mineral industry', released in May. This found that the age profile of women in the industry is concentrated towards those aged 34 and under. Lack of child care was cited as the major reason for leaving the industry. A lack of mentor relationships and support networks for women was identified. The article reports comments by Nicole Hollows, Macarthur Coal's CEO and recently appointed managing director, and others who attended the 'Women in mining symposium'. 1 ref., 6 photos.

  2. Research proposal: Industry convergence - Driving forces, factors and consequences

    OpenAIRE

    Weaver, Benjamin

    2007-01-01

    Industry convergence – the merger of hitherto separate industries – is a phenomenon that has had a profound effect on several industries and received considerable interest among practitioners and business press over the past decades. Despite this, industry con- vergence has only received limited attention from the academic management field, al- though an emergent discussion on convergence can be identified. Prior research is limited by a lack of coherent theoretical definitions of convergence...

  3. Bursts of transposable elements as an evolutionary driving force

    Czech Academy of Sciences Publication Activity Database

    Belyayev, Alexander

    2014-01-01

    Roč. 27, č. 12 (2014), s. 2573-2584 ISSN 1010-061X Institutional support: RVO:67985939 Keywords : evolution * genome * marginal populations * speciation * transposable elements Subject RIV: EF - Botanics Impact factor: 3.232, year: 2014

  4. Forest Fragmentation and Driving Forces in Yingkou, Northeastern China

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2017-03-01

    Full Text Available Forest fragmentation, the process of changing original large and intact forest patches into smaller and isolated areas, significantly influences the balance of surface physical environment, biodiversity, and species richness. Sufficient knowledge of forest fragmentation is necessary to maintain ecological balance and promote sustainable resource utilization. This study combines remote sensing, geographical information systems, and landscape metrics to assess forest fragmentation at landscape and pixel levels during different time periods (2000–2005, 2005–2010, and 2010–2015 in the Yingkou region. Spatial statistical analysis is also used to analyze the relationship between forest landscape fragmentation and its determinants (e.g., natural factors, socioeconomic factors, and proximity factors. Results show that forest patches became smaller, subdivided, and isolated during 2010–2015 at the total landscape level. Local changes occurred in the southwest of the study region or around the development area. Our data also indicate that shrinkage and subdivision were the main forest fragmentation processes during three times, and attrition became the main forest fragmentation process from 2010 to 2015. These changes were significantly influenced by natural factors (e.g., elevation and slope, proximity factors (e.g., distance to city and distance to province roads, and socioeconomic factors (e.g., gross domestic product. Results presented in this study provide valuable insights into the pattern and processes of forest fragmentation and present direct implications for the protection and reasonable utilization of forest resources.

  5. Dynamics and driving forces of hides, skins, leather and leather ...

    African Journals Online (AJOL)

    Footwear and leather goods are constrained by lack of factories, competition from used goods, synthetic plastics and uninformed market. Investment in hides, skins and leather industry supported by training programmes has potential to generate great monetary revenue. Keywords: Hides, skin, leather, value chain, slaughter ...

  6. Advanced nuclear power options: The driving forces and their results

    International Nuclear Information System (INIS)

    Golay, M.W.

    1990-01-01

    Successful nuclear power plant concepts must simultaneously demonstrate satisfactory performance in terms of both safety and economics. In order to be attractive to both electric utility companies and the public, such plants must produce economical electric energy consistent with a level of safety which is acceptable to both the public and the plant owner. Programs for reactor development worldwide can be classified according to whether the reactor concept pursues improved safety or improved economic performance as the primary objective. When improved safety is the primary goal, safety enters the solution of the design problem as a constraint which restricts the set of allowed solutions. Conversely, when improved economic performance is the primary goal it is allowed to be pursued only to an extent which is compatible with stringent safety requirements. The three major reactor coolants under consideration for future advanced reactor use are water, helium and sodium. Reactor development programs focused upon safety and upon economics using each coolant are being pursued worldwide. It is seen that the safety-oriented concepts are typically of lower capacity by approximately an order of magnitude, than the economics-oriented concepts. This is the result, in the former concept, of using less efficient, but more reliable, means of accomplishing essential safety functions. (author)

  7. Regional Relative Price Disparities and Their Driving Forces

    Directory of Open Access Journals (Sweden)

    Eu Joon Chang

    2017-09-01

    Full Text Available This paper studies the long-run behavior of relative price dispersion among cities in Korea with a special emphasis on heterogeneous transitional patterns of price level dynamics. Formal statistical tests indicate considerable evidence for rejecting the null of relative price level convergence among the majority of cities over the sample period of 1985-2015. The analysis of gravity model suggests that the effect of transportation costs on intercity price level differentials is limited, while other socioeconomic factors, such as income, input factor prices, demographic structure, and housing price growth, play key roles in accounting for persistent regional price level disparities. Individual price levels are found to be better explained by a multiple-component model, and the deviations from PPP may be attributed to distinct stochastic common trends that are characterized by income and demographic structure.

  8. Individualization as Driving Force of Clustering Phenomena in Humans

    NARCIS (Netherlands)

    Maes, Michael; Flache, Andreas; Helbing, Dirk

    2010-01-01

    One of the most intriguing dynamics in biological systems is the emergence of clustering, in the sense that individuals self-organize into separate agglomerations in physical or behavioral space. Several theories have been developed to explain clustering in, for instance, multi-cellular organisms,

  9. Operations Data Files, driving force behind International Space Station operations

    Science.gov (United States)

    Hoppenbrouwers, Tom; Ferra, Lionel; Markus, Michael; Wolff, Mikael

    2017-09-01

    Almost all tasks performed by the astronauts on-board the International Space Station (ISS) and by ground controllers in Mission Control Centre, from operation and maintenance of station systems to the execution of scientific experiments or high risk visiting vehicles docking manoeuvres, would not be possible without Operations Data Files (ODF). ODFs are the User Manuals of the Space Station and have multiple faces, going from traditional step-by-step procedures, scripts, cue cards, over displays, to software which guides the crew through the execution of certain tasks. Those key operational documents are standardized as they are used on-board the Space Station by an international crew constantly changing every 3 months. Furthermore this harmonization effort is paramount for consistency as the crew moves from one element to another in a matter of seconds, and from one activity to another. On ground, a significant large group of experts from all International Partners drafts, prepares reviews and approves on a daily basis all Operations Data Files, ensuring their timely availability on-board the ISS for all activities. Unavailability of these operational documents will halt the conduct of experiments or cancel milestone events. This paper will give an insight in the ground preparation work for the ODFs (with a focus on ESA ODF processes) and will present an overview on ODF formats and their usage within the ISS environment today and show how vital they are. Furthermore the focus will be on the recently implemented ODF features, which significantly ease the use of this documentation and improve the efficiency of the astronauts performing the tasks. Examples are short video demonstrations, interactive 3D animations, Execute Tailored Procedures (XTP-versions), tablet products, etc.

  10. Barriers to fruit consumption: Driving forces behind consumer behaviour

    NARCIS (Netherlands)

    Briz, T.; Sijtsema, S.J.; Jasiulewicz, A.; Kyriakidi, A.; Dolors Guàrdia, M.; Berg, van den I.; Lans, van der I.A.

    2008-01-01

    Abstract This study gives more insight in motives and barriers, i.e. positive and negative drivers, for European fruit consumption, as a basis to meet consumer requirements in developing new types of fruits and fruit products and to develop interventions. For that purpose, focus group discussions

  11. Lipid and protein composition as driving force for multiple sclerosis

    Science.gov (United States)

    Beck, Roy; Shaharabani, Rona

    Physical models and experiments often reduce the number of components aiming to address the fundamental mechanisms. Nevertheless, the inherent heterogeneity is an essential ingredient in the biological context. We present our recent efforts to model and understand the development of multiple sclerosis (MS) from a biophysical perspective. Myelin sheath is a multilamellar complex of various lipids and proteins that surround axons and acts as an insulating layer for proper nerve conduction. In MS the myelin structure is disrupted impairing its function. Previous studies showed that MS is correlated with small lipid composition variation and reduction in the adhesive myelin basic protein. We found that such alterations result in pathological phase transition from a lamellar to inverted hexagonal that involve enhanced local curvature. Similar curvatures are also found in vivo in diseased myelin sheaths. Since the etiology and recovery pathways of MS are currently unclear, these findings delineate novel functional roles to dominant constituents in cytoplasmic myelin sheaths, shed new light on mechanisms disrupting lipid-protein complexes, and suggest new courses for diagnosis and treatment for MS.

  12. Exploring driving forces and liquid properties for electrokinetic energy conversion

    NARCIS (Netherlands)

    Nguyen, Trieu

    2015-01-01

    This thesis presents an effort to understand electrokinetic energy conversion systems which are based on motion of ionic charges in micro- and nano-confinements. In particular, both experimentally and theoretically the utilization of different kind of liquids was investigated to convert mechanical

  13. External Costs as Driving Forces of Land Use Changes

    Directory of Open Access Journals (Sweden)

    Dirk Loehr

    2010-04-01

    Full Text Available Land conversion is often not carried out in a sustainable way. The loss of arable land and biodiversity, concern about food security and rising costs of infrastructure due to urban sprawl are just some of the problems under discussion. This paper compares Germany, China and Cambodia. The article points out that, despite huge differences in institutions and governance, unsustainable land use changes mostly have some patterns in common: The beneficiaries of land conversion are often well-organized actors, whereas the costs of land conversion are often shifted to poorly organized groups and to society as a whole. A sustainable land use policy has to look for a better coupling of benefits and costs of land use changes. In order to achieve this goal, the article suggests completing the planning law with a suitable economic framework.

  14. Digital Density as the Driving Force of Digital Transformation Processes

    OpenAIRE

    Bush, Xavier

    2016-01-01

    Digital technologies have increased the influence of technology in business, even changing business models and strategies of organisations. This influence, called Digital Transformation of Business (DT), happens when there is an increase of the number of digital connections, information and interactions. This phenom-ena has been defined as Digital Density (DD) and aims to provide an assessment of the digitalization status of an organization. With the concept of DD we pro-pose the DD Framework, t...

  15. Advanced nuclear power options: The driving forces and their results

    Energy Technology Data Exchange (ETDEWEB)

    Golay, M W [Massachusetts Institute of Technology, Cambridge, MA (United States)

    1990-07-01

    Successful nuclear power plant concepts must simultaneously demonstrate satisfactory performance in terms of both safety and economics. In order to be attractive to both electric utility companies and the public, such plants must produce economical electric energy consistent with a level of safety which is acceptable to both the public and the plant owner. Programs for reactor development worldwide can be classified according to whether the reactor concept pursues improved safety or improved economic performance as the primary objective. When improved safety is the primary goal, safety enters the solution of the design problem as a constraint which restricts the set of allowed solutions. Conversely, when improved economic performance is the primary goal it is allowed to be pursued only to an extent which is compatible with stringent safety requirements. The three major reactor coolants under consideration for future advanced reactor use are water, helium and sodium. Reactor development programs focused upon safety and upon economics using each coolant are being pursued worldwide. It is seen that the safety-oriented concepts are typically of lower capacity by approximately an order of magnitude, than the economics-oriented concepts. This is the result, in the former concept, of using less efficient, but more reliable, means of accomplishing essential safety functions. (author)

  16. Individualization as driving force of clustering phenomena in humans.

    Directory of Open Access Journals (Sweden)

    Michael Mäs

    Full Text Available One of the most intriguing dynamics in biological systems is the emergence of clustering, in the sense that individuals self-organize into separate agglomerations in physical or behavioral space. Several theories have been developed to explain clustering in, for instance, multi-cellular organisms, ant colonies, bee hives, flocks of birds, schools of fish, and animal herds. A persistent puzzle, however, is the clustering of opinions in human populations, particularly when opinions vary continuously, such as the degree to which citizens are in favor of or against a vaccination program. Existing continuous opinion formation models predict "monoculture" in the long run, unless subsets of the population are perfectly separated from each other. Yet, social diversity is a robust empirical phenomenon, although perfect separation is hardly possible in an increasingly connected world. Considering randomness has not overcome the theoretical shortcomings so far. Small perturbations of individual opinions trigger social influence cascades that inevitably lead to monoculture, while larger noise disrupts opinion clusters and results in rampant individualism without any social structure. Our solution to the puzzle builds on recent empirical research, combining the integrative tendencies of social influence with the disintegrative effects of individualization. A key element of the new computational model is an adaptive kind of noise. We conduct computer simulation experiments demonstrating that with this kind of noise a third phase besides individualism and monoculture becomes possible, characterized by the formation of metastable clusters with diversity between and consensus within clusters. When clusters are small, individualization tendencies are too weak to prohibit a fusion of clusters. When clusters grow too large, however, individualization increases in strength, which promotes their splitting. In summary, the new model can explain cultural clustering in human societies. Strikingly, model predictions are not only robust to "noise"-randomness is actually the central mechanism that sustains pluralism and clustering.

  17. Safe handling, economics: Driving forces in radwaste management

    International Nuclear Information System (INIS)

    Strauss, S.D.

    1994-01-01

    This article describes how, faced with tortuous federal and state progress toward provision of disposal facilities, utilities are taking interim steps to deal with mounting spent-fuel and low-level radioactive-waste burdens. Whether for highly radioactive fuel assemblies that have served their designated life in nuclear reactors, or for the low-level radioactive waste materials (LLW) created by maintenance, volume-reduction, or other activities at generating sites, ultimate disposition has become a matter requiring immediate steps to avoid complete exhaustion of storage space at utility sites. A virtual impasse exists in both areas: Regional compacts have moved very slowly toward licensing and construction of new LLW disposal sites, and federal action to meet the 1998 deadline for acceptance of spent fuel, as prescribed by the Nuclear Waste Policy Act in 1982 -- for either temporary storage (with monitored retrieval, MRS) or permanent burial -- has proceeded at a snail's pace

  18. Challenges and Driving Forces for Business Plans in Biobanking.

    Science.gov (United States)

    Macheiner, Tanja; Huppertz, Berthold; Bayer, Michaela; Sargsyan, Karine

    2017-04-01

    Due to increased utilization of biospecimens for research and emergence of new technologies, the availability and quality of biospecimens and their collection are coming more and more into focus. However, the long-term economic situation of biobanks is still mostly unclear. Also, the common sustainable utilization of various international biobanks is challenging due to local differences in sample processing, law and ethics. This article discusses possible strategies to achieve a sustainable utilization of biospecimens as part of the business plan of biobanks. The following questions were addressed as part of a business plan: (1) How can a biobank build up and maintain an up-to-date infrastructure? (2) What kind of funding can support the sustainability of a biobank? (3) Is there an international solution for informed consents to enable sample and data sharing? (4) How can a biobank react during economically unstable periods? (5) Which kind of biobanking research is innovative? (6) What kind of education could be most needful for knowledge transfer in biobanking? (7) Does an expiration date for a biobank make sense according to the period of funding? A strategy for optimal utilization begins with sharing of resources, infrastructure, and investments at the planning stage of a biobank, and continues to the transfer of knowledge and know-how by education. For clinical biobanks in particular, a long-term funding and cost recovery strategy is necessary for sustainable utilization.

  19. Energy analysis of control rod drive mechanism in HTR-10

    International Nuclear Information System (INIS)

    Bo Hanliang; Wu Yuanqiang

    2000-01-01

    This paper presents a theoretical model for the control rod drive mechanism for the 10 MW High Temperature Gas Cooled Reactor (HTR-10) and analyzes accidents which may occur in the drive mechanism, for example, chain break, coupling damage and other damage scenarios. The results show that the matching problem between buffer capability and coupling strength is the main reason for coupling damage; increased temperatures would reduce eddy damping and cause a mismatch between buffer capability and coupling strength; and the displacement of the buffer spring will affect the coupling force. The results provide a theoretical basis for the design of the control rod drive mechanism for HTR-10

  20. Electrical drives for direct drive renewable energy systems

    CERN Document Server

    Mueller, Markus

    2013-01-01

    Wind turbine gearboxes present major reliability issues, leading to great interest in the current development of gearless direct-drive wind energy systems. Offering high reliability, high efficiency and low maintenance, developments in these direct-drive systems point the way to the next generation of wind power, and Electrical drives for direct drive renewable energy systems is an authoritative guide to their design, development and operation. Part one outlines electrical drive technology, beginning with an overview of electrical generators for direct drive systems. Principles of electrical design for permanent magnet generators are discussed, followed by electrical, thermal and structural generator design and systems integration. A review of power electronic converter technology and power electronic converter systems for direct drive renewable energy applications is then conducted. Part two then focuses on wind and marine applications, beginning with a commercial overview of wind turbine drive systems and a...