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1

Internal forces during object manipulation  

PubMed Central

Internal force is a set of contact forces that does not disturb object equilibrium. The elements of the internal force vector cancel each other and, hence, do not contribute to the resultant (manipulation) force acting on the object. The mathematical independence of the internal and manipulation forces allows for their independent (decoupled) control realized in robotic manipulators. To examine whether in humans internal force is coupled with the manipulation force and what grasping strategy the performers utilize, the subjects (n=6) were instructed to make cyclic arm movements with a customized handle. Six combinations of handle orientation and movement direction were tested. These involved: parallel manipulations (1) VV task (vertical orientation and vertical movement) and (2) HH task (horizontal orientation and horizontal movement); orthogonal manipulations (3) VH task (vertical orientation and horizontal movement) and (4) HV task (horizontal orientation and vertical movement); and diagonal manipulations (5) DV task (diagonal orientation and vertical movement) and (6) DH task (diagonal orientation and horizontal movement). Handle weight (from 3.8 to 13.8 N), and movement frequency (from 1 to 3 Hz) were systematically changed. The analysis was performed at the thumb-virtual finger level (VF, an imaginary finger that produces a wrench equal to the sum of wrenches produced by all the fingers). At this level, the forces of interest could be reduced to the internal force and internal moment. During the parallel manipulations, the internal (grip) force was coupled with the manipulation force (producing object acceleration) and the thumb-VF forces increased or decreased in phase: the thumb and VF worked in synchrony to grasp the object more strongly or more weakly. During the orthogonal manipulations, the thumb-VF forces changed out of phase: the plots of the internal force vs. object acceleration resembled an inverted letter V. The HV task was the only task where the relative phase (coupling) between the normal forces of the thumb and VF depended on oscillation frequency. During the diagonal manipulations, the coupling was different in the DV and DH tasks. A novel observation of substantial internal moments is described: the moments produced by the normal finger forces were counterbalanced by the moments produced by the tangential forces such that the resultant moments were close to zero. Implications of the findings for the notion of grasping synergies are discussed.

Gao, Fan; Latash, Mark L.; Zatsiorsky, Vladimir M.

2010-01-01

2

Female labor force participation: an international perspective.  

PubMed

This article gives an international perspective in regard to female participation in the labor force. In most countries women contribute less than men toward the value of recorded production. Social environment, statistical inconsistencies and methods of recording labor all contribute to this inequity. In Britain for instance, women caring for the household duties are in some studies considered to be part of the labor force and in other studies they are not. Further, internationally, women often find themselves in casual, temporary, or seasonal work that goes unrecorded. Defining what "labor force participation" constitutes is a key starting point to any survey. At what age is one considered employable? What constitutes a person "actively seeking" employment? Economists often try to explain labor force participation rate by age, sex, race and income groups and use this information to cite trends. The income-leisure model theorizes that choice of work or non-work by women is based primarily upon wages for work vs. wages for non-work. This theory sees non-labor income exerting a negative influence. Empirical evidence, however, suggests that women will choose work if wages are good regardless of any non-work benefits. Because most men are permanently in the labor force, estimates of labor reserves and projections of supply focus mostly on women. International generalizations are often misleading since trends vary widely among countries. During the last 20 years the global female participation rate has remained almost constant, but this is misleading. The percentage of working women in industrial countries increased 10%; developing countries showed a decrease of 7%. Female rates are often tied closely to shifts in the overall economy, (e.g., a transition from an agricultural to an industrial economy often sees a drop in female labor because subsistence jobs are lost). Of course the ability of women to bear children and the social expectations regarding child care often play a role. It is common in western industrialized countries to see drops in female participation during childbearing years. Countries with the lowest female participation rates are those with strong religious views about women in society, (e.g., Catholic and Muslim countries). PMID:12283641

Psacharopoulos, G; Tzannatos, Z

1989-07-01

3

Participation in Armed Forces, National, and International Sports Activities.  

National Technical Information Service (NTIS)

The Directive reissues DoD Directive 1330.4, November 14, 1968; prescribes DoD policy concerning the participation of Armed Forces personnel in Armed Forces, national, and international sports competitions; establishes a Senior Military Sports Advisor, an...

J. Sass

1987-01-01

4

International Cooperation with Partner Air Forces.  

National Technical Information Service (NTIS)

The U.S. Air Force faces a challenging environment as it devises an approach to managing security cooperation with partner countries. The important mission of countering terrorist and insurgent groups abroad requires working closely with allies and partne...

B. Grill E. Gons J. D. Moroney J. E. Peters K. Cragin

2009-01-01

5

Closed systems with nonconservative internal forces  

Microsoft Academic Search

In this paper we identify the current state of the art for the construction of a closed system of interacting particles, that is, a system which, when isolated, verifies the conservation laws of the total energy, linear momentum, and angular momentum, as well as the uniform motion of the center of mass. The conventional approach via conservative forces is recalled,

A. Tellez-Arenas; J. Fronteau; R. M. Santilli

1979-01-01

6

77 FR 29899 - Safety Zone; International Special Operations Forces Week Capability Exercise, Seddon Channel...  

Federal Register 2010, 2011, 2012, 2013

...International Special Operations Forces Week Capability Exercise, Seddon Channel...International Special Operations Forces Week Capability Exercise. The exercise is scheduled...International Special Operations Forces Week Capability Exercise is scheduled to...

2012-05-21

7

Sources of Thermospheric Variability: Externally Forced and Internally Generated  

NASA Astrophysics Data System (ADS)

Thermospheric variability arises from both externally driven and internally generated physical processes. The external forcing arises from solar EUV, geomagnetic activity, and wave disturbances from the lower atmosphere. Understanding the partitioning of thermospheric density variability between these three main sources remains a critical need. Internally, the variability can arise from the coupling between the plasma and neutral gas, and from internal dynamics. For instance, energy deposited by plasma recombination at the latitude of the equatorial ionization anomaly give rise to neutral density maxima that change from day-to-day. In addition, the seasonal circulation from summer to winter introduces a semi-annual variation (SAV). The magnitude of the SAV depends on the strength of the interhemispheric solar forcing but the cause of the phase modulated has yet to be determined. A review of the various internal processes and the response to external forcing reveals the outstanding challenges in our understanding of the physical system.

Fuller-Rowell, T.

2006-12-01

8

Self-force as probe of internal structure  

NASA Astrophysics Data System (ADS)

The self-force acting on a (scalar or electric) charge held in place outside a massive body contains information about the body’s composition, and can therefore be used as a probe of internal structure. We explore this theme by computing the (scalar or electromagnetic) self-force when the body is a spherical ball of perfect fluid in hydrostatic equilibrium, under the assumption that its rest-mass density and pressure are related by a polytropic equation of state. The body is strongly self-gravitating, and all computations are performed in exact general relativity. The dependence on internal structure is best revealed by expanding the self-force in powers of r-10, with r0 denoting the radial position of the charge outside the body. To the leading order, the self-force scales as r-30 and depends only on the square of the charge and the body’s mass; the leading self-force is universal. The dependence on internal structure is seen at the next order, r-50, through a structure factor that depends on the equation of state. We compute this structure factor for relativistic polytropes, and show that for a fixed mass, it increases linearly with the body’s radius in the case of the scalar self-force, and quadratically with the body’s radius in the case of the electromagnetic self-force. In both cases we find that for a fixed mass and radius, the self-force is smaller if the body is more centrally dense, and larger if the mass density is more uniformly distributed.

Isoyama, Soichiro; Poisson, Eric

2012-08-01

9

The Internal Forces of Creativity: When Hearts Start to Flutter.  

ERIC Educational Resources Information Center

Four artistic people of various ages were interviewed concerning their conscious and unconscious thought during creative activity, emotions which precipitated creative activity and intermingled with cognition, and intrinsic motivators and rewards. The interviews supported research regarding the internal forces of creativity. (Author/JDD)

Gnezda-Smith, Nicole

1994-01-01

10

Venous Ulcer Reappraisal: Insights from an International Task Force  

Microsoft Academic Search

An international task force made up of a panel of 16 experts was mandated to review and objectively evaluate all aspects of chronic venous disease of the leg. All available publications on chronic venous disease of the leg from 1983 to 1997 were identified through computerized search. Three different screenings were then performed in order to select only relevant papers

D. L. Clement

1999-01-01

11

Atomic force microscopy to detect internal live processes in insects  

NASA Astrophysics Data System (ADS)

Here we report on the use of atomic force microscopy (AFM) to study surface oscillations coming from internal live processes of insects. With a specially designed AFM stage to keep an insect motion partially restricted, the AFM can record internal oscillations on different parts of the insect. We demonstrate the method for a fly, mosquito, and lady beetle. We show that AFM can provide information about the spectral behavior that has not been studied so far, 10-600 Hz range, detecting amplitudes down to subnanometer level.

Dokukin, M. E.; Guz, N. V.; Vasilyev, S.; Sokolov, I.

2010-01-01

12

Forced wave motion with internal and boundary damping  

PubMed Central

A d’Alembert-based solution of forced wave motion with internal and boundary damping is presented with the specific intention of investigating the transient response. The dynamic boundary condition is a convenient method to model the absorption and reflection effects of an interface without considering coupled PDE’s. Problems with boundary condition of the form ?w?z+?˜?w?t=0 are not self-adjoint which greatly complicates solution by spectral analysis. However, exact solutions are found with d’Alembert’s method. Solutions are also derived for a time-harmonically forced problem with internal damping and are used to investigate the effect of ultrasound in a bioreactor, particularly the amount of energy delivered to cultured cells. The concise form of the solution simplifies the analysis of acoustic field problems.

Louw, Tobias; Whitney, Scott; Subramanian, Anu; Viljoen, Hendrik

2012-01-01

13

Forced wave motion with internal and boundary damping  

NASA Astrophysics Data System (ADS)

A d'Alembert-based solution of forced wave motion with internal and boundary damping is presented with the specific intention of investigating the transient response. The dynamic boundary condition is a convenient method to model the absorption and reflection effects of an interface without considering coupled PDE's. Problems with boundary condition of the form ?w?z+?~?w?t=0 are not self-adjoint which greatly complicates solution by spectral analysis. However, exact solutions are found with d'Alembert's method. Solutions are also derived for a time-harmonically forced problem with internal damping and are used to investigate the effect of ultrasound in a bioreactor, particularly the amount of energy delivered to cultured cells. The concise form of the solution simplifies the analysis of acoustic field problems.

Louw, Tobias; Whitney, Scott; Subramanian, Anu; Viljoen, Hendrik

2012-01-01

14

Internal forcing of Mercury's long period free librations  

NASA Astrophysics Data System (ADS)

Observations of Mercury's spin rate suggest that, in addition to the forced 88-day mantle libration induced by solar torques, a decadal timescale libration may also be present. It has been proposed that this signal represents an amplified forced libration caused by the periodic 11.86 yr perturbation on Mercury's orbit by Jupiter. Here, we investigate the possibility that a decadal libration may be produced by a forcing internal to the planet. Our mechanism is based on the presence of time-dependent zonal flows generated by convective dynamics in Mercury's fluid core. Through electromagnetic coupling, these flows entrain longitudinal displacements of the inner core, which then entrain mantle librations by gravitational coupling. We construct a simple model to capture this exchange of angular momentum and we show that when the period of the zonal core flows approaches a free libration mode, amplification occurs. Our results suggest that for plausible values of Mercury's internal magnetic field, if the inner core of Mercury is large (ge; 1000 km), decadal mantle libration amplitudes of the order of 10 arcsec can be generated by zonal flows of the order of 1 km yr-1.

Koning, A. H.; Dumberry, M.

2012-09-01

15

Internal forcing of Mercury's long period free librations  

NASA Astrophysics Data System (ADS)

Observations of Mercury's spin rate do not rule out that, in addition to the forced 88-day mantle libration induced by solar torques, a decadal timescale libration may also be present. It has been proposed that this signal represents an amplified forced libration caused by the periodic 11.86 yr perturbation on Mercury's orbit by Jupiter. Here, we investigate the possibility that a decadal libration may be produced by a forcing internal to the planet. Our mechanism is based on the presence of time-dependent zonal flows generated by turbulent convection in Mercury's fluid core. Through electromagnetic coupling, these flows entrain longitudinal displacements of the inner core, which then entrain mantle librations by gravitational coupling. We construct a simple model to capture this exchange of angular momentum. Although core zonal flows are expected to have a broad frequency spectrum, we show that the resulting mantle libration is dominated by the amplification that occurs at the period of the free decadal libration of the combined mantle and inner core. Our results suggest that for plausible values of Mercury's internal magnetic field, if the inner core of Mercury is large (?1000 km), decadal mantle libration amplitudes of the order of 1 arcsec can be generated by zonal flows of the order of 1 km yr-1. Conversely, if future observations can robustly determine an upper bound on the amplitude of Mercury's decadal librations, our results can be used as constraints on the convective dynamics in Mercury's core.

Koning, Alice; Dumberry, Mathieu

2013-03-01

16

An analytical method for internal forces in DOT shield-driven tunnel  

Microsoft Academic Search

This paper presents an analytical solution for the determination of internal forces of a jointed segmental precast DOT (Double-O-tube) lining. The unbalanced force transition method is combined with force method to establish an efficient analytical shortcut that simplifies tests and obtains the solution more effective than the existing methods to determine internal forces in the DOT tunnel lining. The in

Xinyu Hu; Zixin Zhang; Li Teng

2009-01-01

17

Modal decomposition of tidally-forced internal waves  

NASA Astrophysics Data System (ADS)

There exist multiple mechanisms for the breaking of ocean internal waves including critical reflection, shear instabilities, etc. Wave breaking contributes to diapycnal mixing and sediment or nutrient transport. A principal mechanism of internal wave generation is tidal conversion, i.e. time-periodic sloshing of seawater over bathymetry such as the mid-Atlantic ridge. While past theoretical and laboratory experimental work has principally considered the scenario in which internal waves are forced by only one frequency, tidal flow has a range of diurnal and semi-diurnal frequency components (i.e. M2, S2, K1, etc.). Correspondingly, tidal conversion may generate a broad wave spectrum comprising different frequencies and vertical wavenumbers. Such details are relevant in estimating the location and amount of mixing that occurs upon wave breaking. In this work, an algorithm has been developed that performs a spatial and temporal decomposition of polychromatic internal waves generated by tidal sloshing over topography, with constant buoyancy frequency N. Starting with vertical velocity timeseries data of a given internal wave field, a fast Fourier transform (FFT) with windowing and zero-padding is employed in order to determine the (discrete) frequencies present. Frequency-specific complex mode strengths ?jn for the internal waves can then be recovered. In order to verify the results of the algorithm, synthetic laboratory experimental data corresponding to the idealized problem of tidal sloshing over 2D Gaussian topography are generated and superposed for a variety of forcing frequencies (ranging from?j/N = 1/10 to?j/N = 9/10). The calculated frequencies and mode strengths are compared with the known values from the synthetic data. The mode strengths ?jn are either calculated directly or as a ratio normalized by the mode 1 mode strength. In either scenario, the resulting mode strengths can be sensitive to errors in the frequencies recovered via FFT. However, when exact frequencies are used the numerically calculated mode strengths show excellent qualitative and quantitative agreement with those from the synthetic data. The algorithm is currently being extended to the scenario in which the internal wave forcing frequencies form a continuous frequency spectrum rather than well-defined discrete peaks, such as those arising from fluid-fluid interactions (e.g. an intrusive gravity current propagating through a stratified ambient). Such wave fields present numerous additional challenges in the calculation of the associated mode strengths. The algorithm described above allows for the determination of the temporal and spatial structure of an internal wave field without a-priori knowledge of the specifics of its generation. Further adaptations such as variable N for realistic background stratification would allow for application to more geophysically relevant scenarios, and thus the analysis of observational data.

Kaminski, A. K.; Flynn, M. R.

2012-04-01

18

Human trafficking and forced labour : A criticism of the International Labour Organisation  

Microsoft Academic Search

Purpose – During the last ten years, the International Labour Organisation (ILO), and some other international organizations, have increasingly addressed human trafficking from a “forced labour” perspective. The purpose of this paper is to clarify the terminology in relation to human trafficking and forced labour, to highlight the links between them, and to provide a critique of the ILO approach.

Kadriye Bakirci

2009-01-01

19

The Virtual Linkage: A Model for Internal Forces in Multi-Grasp Manipulation  

Microsoft Academic Search

We propose a model to characterize internal forcesand moments during multi-grasp manipulation. Theproposed approach is based on construction of a physicalmodel, called the virtual linkage, which is a closedchain mechanism that represents the object being manipulated.Forces and moments applied at the grasppoints of this linkage cause joint forces and torquesat its actuators. When these actuators are subjectedto the opposing forces

David Williams; Oussama Khatib

1993-01-01

20

Computation of grasp internal forces for stably grasping multiple objects  

Microsoft Academic Search

When multiple objects are grasped by a multifingered hand, the feasible grasp finger forces are limited directionally because of the geometrical and frictional conditions on the contact parts among the objects. The paper proposes an approach for judging if a group of given fingertip positions is feasible and obtaining the graspable finger force region. In the paper, the generable contact

Yong Yu; Kenro Fukuda; Showzow Tsujio

2001-01-01

21

Subsidiary entrepreneurship, internal and external competitive forces, and subsidiary performance  

Microsoft Academic Search

The Multinational Subsidiary is conceptualized as a semi-autonomous entity with entrepreneurial potential, within a complex competitive arena, consisting of an internal environment of other subsidiaries, internal customers and suppliers, and an external environment consisting of customers, suppliers and competitors. The relative strength of these competitive environments shapes the subsidiary's options; and it is then up to subsidiary manager to take

Julian Birkinshaw; Neil Hood; Stephen Young

2005-01-01

22

Reflections on a Seminal Force in International Accounting  

ERIC Educational Resources Information Center

|Accounting is a manifestation of several important environmental factors within a country, including economic, educational and political, and, as such, is evolutionary in accordance with those changing social structures. Because of the major impact that international accounting has had on countries' internal accounting systems, it is important to…

Cascini, Karen T.

2007-01-01

23

International versus Local Retail Sales Force Training in Singapore  

Microsoft Academic Search

Sales training practices of international and domestic retailers are contrasted in the context of the internationalizing retail environment of Singapore. An empirical evaluation identifies significant differences between domestic and international retailers with respect to the use of various sales training techniques, particularly: the formality of training practices, the implementation of sales training, and follow-up to sales training. Additionally, sales techniques

Earl D. Honeycutt jr; Zafar U. Ahmed; Sandra Mottner

2004-01-01

24

The Police Use of Deadly Force: International Comparisons  

Microsoft Academic Search

While the societies of the United States of America and Canada are similar in many ways, recent research has noted significant differences in the rates of extreme violence between the two nations. Extreme violence includes the police use of deadly force, the murder of police officers by an assailant, the homicide rate of the general population and violent crime such

Rick Parent

2006-01-01

25

Plan for conducting an international machine tool task force  

Microsoft Academic Search

The basic objectives of the Machine Tool Task Force (MTTF) are to characterize and summarize the state of the art of cutting machine tool technology and to identify promising areas of future R and D. These goals will be accomplished with a series of multidisciplinary teams of prominent experts and individuals experienced in the specialized technologies of machine tools or

G. P. Sutton; E. R. McClure; J. F. Schuman

1978-01-01

26

Internal Versus SST-Forced Atmospheric Variability as Simulated by an Atmospheric General Circulation Model  

Microsoft Academic Search

The variability of atmospheric flow is analyzed by separating it into an internal part due to atmospheric dynamics only and an external (or forced) part due to the variability of sea surface temperature forcing. The two modes of variability are identified by performing an ensemble of seven independent long-term simulations of the atmospheric response to observed SST (1970-1988) with the

Ali Harzallah; Robert Sadourny

1995-01-01

27

Measurement of internal forces in superconducting accelerator magnets with strain gauge transducers  

Microsoft Academic Search

An improved method has been developed for the measurement of internal forces in superconducting accelerator magnets, in particular the compressive stresses in coils and the end restraint forces on the coils. The transducers have been designed to provide improved sensitivity to purely mechanical strain by using bending mode deflections for sensing the applied loads. Strain gauge resistance measurements are made

C. L. Goodzeit; M. D. Anerella; G. L. Ganetis

1989-01-01

28

Researching the use of force: the background to the international project  

Microsoft Academic Search

This article provides the background to an international project on use of force by the police that was carried out in seven\\u000a countries. Force is often considered to be the defining characteristic of policing and much research has been conducted on\\u000a the determinants, prevalence and control of the use of force, particularly in the United States. However, little work has

Philip Stenning; Christopher Birkbeck; Otto Adang; David Baker; Thomas Feltes; Luis Gerardo Gabaldón; Maki Haberfeld; Eduardo Paes Machado; P. A. J. Waddington

2009-01-01

29

Internal and forced modes of variability in the Indian Ocean  

NASA Astrophysics Data System (ADS)

Ocean-atmosphere variability in the tropical Indian Ocean is investigated using observational data and ensemble experiments with a coupled general circulation model. In one ensemble (IO runs) the ocean-model domain is limited to the Indian Ocean and observed sea surface temperatures force the atmospheric model elsewhere. In a second ensemble (TPIO) the coupled domain includes the Tropical Pacific. The IO runs display a coupled mode of variability with several characteristics of the Indian Ocean Dipole (IOD), but independent on ENSO (El-Niño Southern Oscillation). Changes in the Walker circulation induced by ENSO are insufficient to trigger IOD events. In the TPIO runs ENSO variability is correlated with the IOD mode as observed. Oceanic processes are responsible for an essential component of ENSO forcing in the Indian Ocean. The ENSO phase conditions the thermocline depth in the Indonesian Throughflow region and in the southeastern IO. TPIO results are in agreement with SODA reanalysis.

Bracco, A.; Kucharski, F.; Molteni, F.; Hazeleger, W.; Severijns, C.

2005-06-01

30

Stress Analysis of an Internally Balanced Force System.  

National Technical Information Service (NTIS)

A two-dimensional, analytical model is formulated for a dual-phase, particulate composite which approximates the internal structures of certain rock types. The finite element method is used to analyze the elastic response of this model to various static l...

A. T. F. Chen

1975-01-01

31

Atomic force and total internal reflection fluorescence microscopy for the study of force transmission in endothelial cells.  

PubMed Central

This paper describes the combined use of atomic force microscopy (AFM) and total internal reflection fluorescence microscopy (TIRFM) to examine the transmission of force from the apical cell membrane to the basal cell membrane. A Bioscope AFM was mounted on an inverted microscope, the stage of which was configured for TIRFM imaging of fluorescently labeled human umbilical vein endothelial cells (HUVECs). Variable-angle TIRFM experiments were conducted to calibrate the coupling angle with the depth of penetration of the evanescent wave. A measure of cellular mechanical properties was obtained by collecting a set of force curves over the entire apical cell surface. A linear regression fit of the force-indentation curves to an elastic model yields an elastic modulus of 7.22 +/- 0. 46 kPa over the nucleus, 2.97 +/- 0.79 kPa over the cell body in proximity to the nucleus, and 1.27 +/- 0.36 kPa on the cell body near the edge. Stress transmission was investigated by imaging the response of the basal surface to localized force application over the apical surface. The focal contacts changed in position and contact area when forces of 0.3-0.5 nN were applied. There was a significant increase in focal contact area when the force was removed (p < 0.01) from the nucleus as compared to the contact area before force application. There was no significant change in focal contact coverage area before and after force application over the edge. The results suggest that cells transfer localized stress from the apical to the basal surface globally, resulting in rearrangement of contacts on the basal surface.

Mathur, A B; Truskey, G A; Reichert, W M

2000-01-01

32

Comparative analysis of internal friction and natural frequency measured by free decay and forced vibration  

SciTech Connect

Relations between various values of the internal friction (tg{delta}, Q{sup -1}, Q{sup -1*}, and {lambda}/{pi}) measured by free decay and forced vibration are analyzed systemically based on a fundamental mechanical model in this paper. Additionally, relations between various natural frequencies, such as vibration frequency of free decay {omega}{sub FD}, displacement-resonant frequency of forced vibration {omega}{sub d}, and velocity-resonant frequency of forced vibration {omega}{sub 0} are calculated. Moreover, measurement of natural frequencies of a copper specimen of 99.9% purity has been made to demonstrate the relation between the measured natural frequencies of the system by forced vibration and free decay. These results are of importance for not only more accurate measurement of the elastic modulus of materials but also the data conversion between different internal friction measurements.

Wang, Y. Z.; Ding, X. D.; Xiong, X. M.; Zhang, J. X. [State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen (Zhongshan) University, Guangzhou 510275 (China) and Department of Physics, Sun Yat-sen (Zhongshan) University, Guangzhou 510275 (China)

2007-10-15

33

America in Transition: The International Frontier. Report of the Task Force on International Education.  

ERIC Educational Resources Information Center

More than ever, U.S. economic well-being is intertwined with that of other countries through expanding international trade, financial markets, and investments. National security, and even world stability, depend upon U.S. understanding of and communication with other countries. Therefore, international education must be an integral part of the…

National Governors' Association, Washington, DC.

34

Police officer characteristics and internal affairs investigations for use of force allegations  

Microsoft Academic Search

The purpose of the study was to investigate whether there was a relationship between police officer characteristics (e.g., experience, race, gender, age) and internal affairs investigations for allegations of use of force. Cumulative logistic regression models were fitted to data extracted from personnel files of officers employed by the Riverside County Sheriff's Department for the years 1996 through 2000. Analysis

James P. McElvain; Augustine J. Kposowa

2004-01-01

35

Simulating the winter North Atlantic Oscillation: the roles of internal variability and greenhouse gas forcing  

Microsoft Academic Search

Analysis of simulations with seven coupled climate models demonstrates that the observed variations in the winter North Atlantic Oscillation (NAO), particularly the increase from the 1960s to the 1990s, are not compatible with either the internally generated variability nor the response to increasing greenhouse gas forcing simulated by these models. The observed NAO record can be explained by a combination

T. J. Osborn

2004-01-01

36

Ultrasonic imaging of internal vibration of soft tissue under forced vibration  

Microsoft Academic Search

An imaging system that can display both the amplitude and phase maps of internal vibration in soft tissues for forced low-frequency vibration is described. In this method, low-frequency sinusoidal vibration of frequency under several hundred hertz is applied from the surface of the sample and the resulting movement in it is measured from the Doppler frequency shift of the simultaneously

YOSHIKI YAMAKOSHI; JUNICHI SATO; TAKUSO SATO

1990-01-01

37

Counter-Terrorism and the Use of Force in International Law.  

National Technical Information Service (NTIS)

In this paper, Michael Schmitt explores the legality of the attacks against Al Qaeda and the Taliban under the 'jus ad bellum,' that component of international law that governs when a State may resort to force as an instrument of national policy. Although...

M. N. Schmitt

2002-01-01

38

Stress concentration factors at welds in pipelines and tanks subjected to internal pressure and axial force  

Microsoft Academic Search

In this paper, analytical expressions for stress concentration factors in pipes subjected to internal pressure and axial force are derived for a number of design cases based on classical shell theory. The effect of fabrication tolerances in simple butt welds is assessed. Analyses based on classical mechanics are compared with results from axisymmetric finite element analyses for verification of the

Inge Lotsberg

2008-01-01

39

Normal-internal resonances in quasi-periodically forced oscillators: a conservative approach  

NASA Astrophysics Data System (ADS)

We perform a bifurcation analysis of normal-internal resonances in parametrized families of quasi-periodically forced Hamiltonian oscillators, for small forcing. The unforced system is a one degree of freedom oscillator, called the `backbone' system; forced, the system is a skew-product flow with a quasi-periodic driving with n basic frequencies. The dynamics of the forced system are simplified by averaging over the orbits of a linearization of the unforced system. The averaged system turns out to have the same structure as in the well-known case of periodic forcing (n = 1); for a real analytic system, the non-integrable part can even be made exponentially small in the forcing strength. We investigate the persistence and the bifurcations of quasi-periodic n-dimensional tori in the averaged system, filling normal-internal resonance `gaps' that had been excluded in previous analyses. However, these gaps cannot completely be filled up: secondary resonance gaps appear, to which the averaging analysis can be applied again. This phenomenon of `gaps within gaps' makes the quasi-periodic case more complicated than the periodic case.

Broer, Henk; Hanßmann, Heinz; Jorba, Àngel; Villanueva, Jordi; Wagener, Florian

2003-09-01

40

A Critical Look at Climate Models: External Aerosol Forcing and Internal Feedback  

NASA Astrophysics Data System (ADS)

We examine the globally averaged surface temperature record, from 1900 to present, in terms of simulations presented within IPCC (2007) as well as the historical change in external factors that drive surface radiative forcing. We illustrate, as noted by Kiehl (2007) and Schwartz et al. (2007), that IPCC (2007) models have been tuned to match the observed temperature record via use of either substantial internal feedbacks to offset a large net cooling due to anthropogenic aerosols or else use of moderate internal feedbacks to offset modest aerosol cooling. We show that this tuning of climate models, while perhaps benign for our understanding of climate from 1900 to present, has considerable consequences for projections of future climate. The external forcing of climate by anthropogenic aerosols will be ameliorated during the next century due to air quality concerns; temperatures projected by models with large internal feedback diverge from temperatures projected by models with weak feedback as this aerosol forcing diminishes. We suggest uncertainties in the projection of future climate would be greatly reduced if the community could precisely define the net effect, on surface radiative forcing, of anthropogenic aerosols for the present-day world.

Salawitch, R. J.; Mascioli, N.; Canty, T. P.

2011-12-01

41

FRAX(®) Clinical Task Force of the 2010 Joint International Society for Clinical Densitometry & International Osteoporosis Foundation Position Development Conference.  

PubMed

The World Health Organization fracture risk assessment tool, FRAX(®), is an advance in clinical care that can assist in clinical decision-making. However, with increasing clinical utilization, numerous questions have arisen regarding how to best estimate fracture risk in an individual patient. Recognizing the need to assist clinicians in optimal use of FRAX(®), the International Osteoporosis Foundation (IOF) in conjunction with the International Society for Clinical Densitometry (ISCD) assembled an international panel of experts that ultimately developed joint Official Positions of the ISCD and IOF advising clinicians regarding FRAX(®) usage. As part of the process, the charge of the FRAX(®) Clinical Task Force was to review and synthesize data surrounding a number of recognized clinical risk factors including rheumatoid arthritis, smoking, alcohol, prior fracture, falls, bone turnover markers and glucocorticoid use. This synthesis was presented to the expert panel and constitutes the data on which the subsequent Official Positions are predicated. A summary of the Clinical Task Force composition and charge is presented here. PMID:21810522

McCloskey, Eugene V; Binkley, Neil

42

Portal Motor Velocity and Internal Force Resisting Viral DNA Packaging in Bacteriophage ?29  

PubMed Central

During the assembly of many viruses, a powerful molecular motor compacts the genome into a preassembled capsid. Here, we present measurements of viral DNA packaging in bacteriophage ?29 using an improved optical tweezers method that allows DNA translocation to be measured from initiation to completion. This method allowed us to study the previously uncharacterized early stages of packaging and facilitated more accurate measurement of the length of DNA packaged. We measured the motor velocity versus load at near-zero filling and developed a ramped DNA stretching technique that allowed us to measure the velocity versus capsid filling at near-zero load. These measurements reveal that the motor can generate significantly higher velocities and forces than detected previously. Toward the end of packaging, the internal force resisting DNA confinement rises steeply, consistent with the trend predicted by many theoretical models. However, the force rises to a higher magnitude, particularly during the early stages of packaging, than predicted by models that assume coaxial inverse spooling of the DNA. This finding suggests that the DNA is not arranged in that conformation during the early stages of packaging and indicates that internal force is available to drive complete genome ejection in vitro. The maximum force exceeds 100 pN, which is about one-half that predicted to rupture the capsid shell.

Rickgauer, John Peter; Fuller, Derek N.; Grimes, Shelley; Jardine, Paul J.; Anderson, Dwight L.; Smith, Douglas E.

2008-01-01

43

Measurement of internal forces in superconducting accelerator magnets with strain gauge transducers  

SciTech Connect

An improved method has been developed for the measurement of internal forces in superconducting accelerator magnets, in particular the compressive stresses in coils and the end restraint forces on the coils. The transducers have been designed to provide improved sensitivity to purely mechanical strain by using bending mode deflections for sensing the applied loads. Strain gauge resistance measurements are made with a new system that eliminates sources of errors due to spurious resistance changes in interconnecting wiring and solder joints. The design of the transducers and their measurement system is presented along with a discussion of the method of compensation for thermal and magnetic effects, methods of calibration with typical calibration data, and measured effects in actual magnets of the thermal stress changes from cooldown and the Lorentz forces during magnet excitation.

Goodzeit, C.L.; Anerella, M.D.; Ganetis, G.L.

1989-03-01

44

Analysis of squat and stoop dynamic liftings: muscle forces and internal spinal loads  

Microsoft Academic Search

Despite the well-recognized role of lifting in back injuries, the relative biomechanical merits of squat versus stoop lifting\\u000a remain controversial. In vivo kinematics measurements and model studies are combined to estimate trunk muscle forces and internal\\u000a spinal loads under dynamic squat and stoop lifts with and without load in hands. Measurements were performed on healthy subjects\\u000a to collect segmental rotations

Babak Bazrgari; Aboulfazl Shirazi-Adl; Navid Arjmand

2007-01-01

45

The conjugate heat transfer from an internal heated small strip in a forced laminar flow  

Microsoft Academic Search

An asymptotic and numerical investigation was conducted for the cooling process, by a forced laminar flow, of a small strip\\u000a with a non-uniform heat source. The nondimensional temperature distribution in the strip has been obtained as a function of\\u000a the following parameters: (a) the intensity and distribution of the internal heat sources, (b) the aspect ratio of the strip,\\u000a (c)

O. Bautista; F. Méndez; C. Treviño

2001-01-01

46

Meteorological and internal wave forcing of seiches along the Sri Lanka coast  

NASA Astrophysics Data System (ADS)

Regularly observed seiches from tide gauge records around the Sri Lanka coast have been analyzed to determine the forcing mechanisms. The seiche periods range from a few 10s of min to 2 h. Fortnightly and seasonal variations of seiche amplitudes are clearly visible on the east coast. These seiche amplitudes are particularly large approximately 6-8 days after spring tides, with maximum seiche amplitudes observed during March-April and October-November, suggesting that the seiche variation could be related to stratification and internal wave activity. There is no visible fortnightly and seasonal variation of seiche amplitudes in west coast records. Instead, they show a daily pattern with relatively larger seiches around 1000 LT, suggesting that the seiches on the west coast could result from diurnal atmospheric forcing. Barotropic and two-layer models have been developed to investigate the influence of atmospheric forcing and internal wave activity on the seiches. A barotropic model applied to the west coast shows that the daily seiche amplitude variation could be simulated with cyclic diurnal meteorological forcing. Two-layer model runs for Trincomalee Bay and the adjacent east coast shelf suggest that seiche amplitudes are proportional to vertical stratification and mixed layer depths. Therefore, the observed seiches there could be excited by internal waves, which originate as far away as the Andaman Sea during spring tides and have a travel time of 6-8 days to the Sri Lankan east coast. However, further studies, including direct measurements of internal wave activity within the region, are required to confirm this hypothesis.

Wijeratne, E. M. S.; Woodworth, P. L.; Pugh, D. T.

2010-03-01

47

The future of general internal medicine. Report and recommendations from the Society of General Internal Medicine (SGIM) Task Force on the Domain of General Internal Medicine.  

PubMed

The Society of General Internal Medicine asked a task force to redefine the domain of general internal medicine. The task force believes that the chaos and dysfunction that characterize today's medical care, and the challenges facing general internal medicine, should spur innovation. These are our recommendations: while remaining true to its core values and competencies, general internal medicine should stay both broad and deep-ranging from uncomplicated primary care to continuous care of patients with multiple, complex, chronic diseases. Postgraduate and continuing education should develop mastery. Wherever they practice, general internists should be able to lead teams and be responsible for the care their teams give, embrace changes in information systems, and aim to provide most of the care their patients require. Current financing of physician services, especially fee-for-service, must be changed to recognize the value of services performed outside the traditional face-to-face visit and give practitioners incentives to improve quality and efficiency, and provide comprehensive, ongoing care. General internal medicine residency training should be reformed to provide both broad and deep medical knowledge, as well as mastery of informatics, management, and team leadership. General internal medicine residents should have options to tailor their final 1 to 2 years to fit their practice goals, often earning a certificate of added qualification (CAQ) in special generalist fields. Research will expand to include practice and operations management, developing more effective shared decision making and transparent medical records, and promoting the close personal connection that both doctors and patients want. We believe these changes constitute a paradigm shift that can benefit patients and the public and reenergize general internal medicine. PMID:14748863

Larson, Eric B; Fihn, Stephan D; Kirk, Lynne M; Levinson, Wendy; Loge, Ronald V; Reynolds, Eileen; Sandy, Lewis; Schroeder, Steven; Wenger, Neil; Williams, Mark

2004-01-01

48

Forced migration and mental health: prolonged internal displacement, return migration and resilience.  

PubMed

Forced internal displacement has been rising steadily, mainly due to conflict. Many internally displaced people (IDP) experience prolonged displacement. Global research evidence suggests that many of these IDP are at high risk for developing mental disorders, adding weight to the global burden of disease. However, individual and community resilience may act as protective factors. Return migration may be an option for some IDP populations, especially when conflicts end, although return migration may itself be associated with worse mental health. Limited evidence is available on effects of resettlement or return migration following prolonged forced internal displacement on mental health. Also, the role of resilience factors remains to be clarified following situations of prolonged displacement. The public health impact of internal displacement is not clearly understood. Epidemiological and interventional research in IDP mental health needs to look beyond medicalised models and encompass broader social and cultural aspects. The resilience factor should be integrated and explored more in mental health research among IDP and a clearly focused multidisciplinary approach is advocated. PMID:24029841

Siriwardhana, Chesmal; Stewart, Robert

2012-12-21

49

Statistical thermodynamics of internal rotation in a hindering potential of mean force obtained from computer simulations.  

PubMed

A method of statistical estimation is applied to the problem of one-dimensional internal rotation in a hindering potential of mean force. The hindering potential, which may have a completely general shape, is expanded in a Fourier series, the coefficients of which are estimated by fitting an appropriate statistical-mechanical distribution to the random variable of internal rotation angle. The function of reduced moment of inertia of an internal rotation is averaged over the thermodynamic ensemble of atomic configurations of the molecule obtained in stochastic simulations. When quantum effects are not important, an accurate estimate of the absolute internal rotation entropy of a molecule with a single rotatable bond is obtained. When there is more than one rotatable bond, the "marginal" statistical-mechanical properties corresponding to a given internal rotational degree of freedom are reduced. The method is illustrated using Monte Carlo simulations of two public health relevant halocarbon molecules, each having a single internal-rotation degree of freedom, and a molecular dynamics simulation of an immunologically relevant polypeptide, in which several dihedral angles are analyzed. PMID:12820124

Hnizdo, Vladimir; Fedorowicz, Adam; Singh, Harshinder; Demchuk, Eugene

2003-07-30

50

Development and Testing of a New Three Component Short Duration Internal Force Balance for Heg  

NASA Astrophysics Data System (ADS)

A new short duration internal force balance for the High Enthalpy Shock Tunnel G¨ottingen (HEG) to measure lift, pitching moment and drag has been designed, calibrated and tested. The balance is able to measures forces of the order of milliseconds on instrumented models from angles of attack of -40 to 20Æ. Tests were performed on a 303 mm long, 10Æ half angle blunt cone at angles of attack from 0 to -20Æ. The tests were conducted at two test conditions with a Mach number of 7.8 and total enthalpies of 3.0 and 3.5 MJ/kg. At 0Æ angle of attack, the measured axial coefficient was recovered to within 6% when compared to computational fluid dynamic (CFD) simulations. A constant axial (drag) coefficient of 0.10 was obtained for the conical model over dynamic pressures ranging from 30 to 70 kPa. As the angle of attack was varied from 0 to -20Æ, the axial coefficient increased to 0.24, the normal coefficient decreased to -0.57 and the pitching moment coefficient (about the model tip) increased to 0.38. At -10Æ, the axial and normal coefficients were within 6% and 9% respectively of CFD predictions while the centre of pressure (based on chord length) was within 2%. Key words: Short duration force measurement; Hypersonic; Blunt cone; Shock tunnel.

Robinson, M. J.; Schramm, J. M.; Hannemann, K.

2005-02-01

51

Nonlinear multimode dynamics and internal resonances of the scan process in noncontacting atomic force microscopy  

NASA Astrophysics Data System (ADS)

The focus of this paper is on the nonlinear multimode dynamics of a moving microbeam for noncontacting atomic force microscopy (AFM). An initial-boundary-value problem is consistently formulated, which includes both nonlinear dynamics of a microcantilever with a localized atomic interaction force, and a horizontal boundary condition for a constant scan speed and its control. The model considered is obtained using the extended Hamilton's principle, which yields two partial differential equations for the combined horizontal and vertical motions. The model incorporates, for the first time to our knowledge, two independent time-varying terms that depict the vertical base excitation of the AFM and the horizontal forcing term depicts the periodic scanning motion of the cantilever. Manipulation of these equations via a Lagrange multiplier enables construction of a modified equation of motion, which is reduced, via Galerkin's method, to a three-mode dynamical system, corresponding to finite amplitude AFM dynamics. The analysis includes a numerical study of the strongly nonlinear system culminating with a stability map describing an escape bifurcation threshold where the tip, at the free end of the microbeam, ``jumps to contact'' with the sample. Results include periodic, quasiperiodic, and non-stationary chaotic-like solutions corresponding to primary and secondary internal combination resonances, where the latter corresponds to energy balance between the cantilever modes.

Hornstein, S.; Gottlieb, O.

2012-10-01

52

Forces  

NSDL National Science Digital Library

The representation depicts what forces are and how they can change the motion and shape of objects in an animated slide show. This resource also includes an interactive test and review of the material, and can be downloaded for offline use.

53

Report on the first international comparison of small force facilities: a pilot study at the micronewton level  

NASA Astrophysics Data System (ADS)

Measurements of forces less than a micronewton are critical when examining the mechanical behaviour of materials and devices at characteristic length scales below a micrometre. As a result, specification standards for nanomechanical tests and test equipment are being proposed by international standards organizations, and an infrastructure for traceable small force calibration is developing. In this context, results are reported from the first interlaboratory comparison of micronewton-level force metrology. The basis of the comparison was the calibration of a set of five piezoresistive cantilever force sensors similar to those used for atomic force microscopes but employed here as transfer artefacts. The artefacts were circulated among four national metrology institutes with each using their own force balance to calibrate the stiffness (force change per unit displacement) and sensitivity (signal output change per unit force) of the artefacts. By considering the weighted mean of the stiffness and sensitivity values reported for a given artefact, reference values were obtained. The largest contributing uncertainty components were due to the transfer artefacts themselves, rather than from the measurements of the physical quantities of force, voltage and displacement. The results imply that it should be possible to determine cantilever stiffness using force balance techniques with an accuracy of better than 1% if necessary, but that improvements in the ability to orient the transfer artefacts, to characterize the non-linearity of their output, and to compensate for the stiffness of the associated fixtures and load frames are required if the resolution of future comparisons is to improve.

Kim, Min-Seok; Pratt, Jon R.; Brand, Uwe; Jones, Christopher W.

2012-02-01

54

Investigation of forced convection heat transfer of supercritical pressure water in a vertically upward internally ribbed tube  

Microsoft Academic Search

In the present paper, the forced convection heat transfer characteristics of water in a vertically upward internally ribbed tube at supercritical pressures were investigated experimentally. The six-head internally ribbed tube is made of SA-213T12 steel with an outer diameter of 31.8mm and a wall thickness of 6mm and the mean inside diameter of the tube is measured to be 17.6mm.

Jianguo Wang; Huixiong Li; Bin Guo; Shuiqing Yu; Yuqian Zhang; Tingkuan Chen

2009-01-01

55

Depression and elevation internal solitary waves in a two-layer fluid and their forces on cylindrical piles  

NASA Astrophysics Data System (ADS)

Both large amplitude depression and elevation internal solitary waves (ISWs) were observed on the continental shelf of the northwest South China Sea (SCS) during the Wenchang Internal Wave Experiment. In this study, we investigate the characteristics of depression and elevation ISWs based on comparisons between observational results and internal wave theories. It is suggested that the large amplitude depression wave is better represented by the extended Korteweg-de Vries (EKdV) theory than by the KdV model, whereas the large amplitude elevation wave is in better agreement with the KdV equation than with the EKdV theory. Wave-induced forces on a supposed small-diameter cylindrical pile by depression and elevation waves are also estimated using the internal wave theory and Morison formula. The wave-induced force by elevation ISWs is rarely reported in the literature. It is found that the force induced by the elevation wave differs significantly from that by the depression wave, and the elevation wave generally produces greater force on the pile in the lower water column than the depression wave. These results show that ISWs in the study area can present a serious threat to ocean engineering structures, and should not be ignored in the design of oil platforms and ocean operations.

Xu, Zhenhua; Yin, Baoshu; Yang, Hongwei; Qi, Jifeng

2012-07-01

56

Health care system chaos should spur innovation: summary of a report of the Society of General Internal Medicine Task Force on the Domain of General Internal Medicine.  

PubMed

The Society of General Internal Medicine asked a task force to redefine the domain of general internal medicine. The Society believes that the chaos and dysfunction that characterize today's medical care and the challenges facing general internal medicine should spur innovation. The task force proposed the following recommendations. Remaining true to its core values and competencies, general internal medicine should stay both broad and deep, ranging from uncomplicated primary care to continuous care of patients with multiple, complex, chronic diseases. Postgraduate and continuing education should develop mastery. Wherever they practice, general internists should be able to lead teams and be responsible for the care given by their teams, embrace changes in information systems, and aim to provide most of the care required by their patients. Current financing of physician services, especially fee-for-service, must be changed to recognize the value of services performed outside the traditional face-to-face visit and give practitioners incentives to improve quality and efficiency and provide comprehensive, ongoing care. General internal medicine residency training should provide both broad and deep medical knowledge as well as mastery of informatics, management, and team leadership. General internal medicine residents should have options to tailor their final 1 to 2 years to fit their practice goals, often earning a certificate of added qualification in generalist fields. Research should expand to include practice and operations management, developing more effective shared decision making and transparent medical records and promoting the close personal connection that both doctors and patients want. The task force believes that these changes will benefit patients and the public and reenergize general internal medicine. PMID:15096335

Larson, Eric B

2004-04-20

57

On computation of grasp internal forces for stably grasping multiple objects  

Microsoft Academic Search

When multiple objects are grasped by a multifingered hand, the feasible grasp finger forces are limited directionally because of the geometrical and frictional conditions on the contact parts among the objects. This paper proposes an approach for judging if a group of given fingertip positions is feasible and obtaining the graspable finger force region. In this paper, the generable contact

Y. Yu; K. Fukuda; S. Tsujio

2001-01-01

58

High Refractive Index Silicone Gels for Simultaneous Total Internal Reflection Fluorescence and Traction Force Microscopy of Adherent Cells  

PubMed Central

Substrate rigidity profoundly impacts cellular behaviors such as migration, gene expression, and cell fate. Total Internal Reflection Fluorescence (TIRF) microscopy enables selective visualization of the dynamics of substrate adhesions, vesicle trafficking, and biochemical signaling at the cell-substrate interface. Here we apply high-refractive-index silicone gels to perform TIRF microscopy on substrates with a wide range of physiological elastic moduli and simultaneously measure traction forces exerted by cells on the substrate.

Besser, Achim; Sundd, Prithu; Ley, Klaus; Danuser, Gaudenz; Ginsberg, Mark H.; Groisman, Alex

2011-01-01

59

Fluctuating forces caused by internal two-phase flow on bends and tees  

NASA Astrophysics Data System (ADS)

The time-dependent forces resulting from a two-phase air water mixture flowing in an elbow and a tee are measured. Their magnitudes as well as their spectral contents are analyzed. Comparison is made with previous experimental results on similar systems. For practical applications a dimensionless form is proposed to relate the characteristics of these forces to the parameters defining the flow and the geometry of the piping. Using a momentum balance we show that these forces are correlated with local measurements of the void fraction in the flow.

Riverin, J. L.; de Langre, E.; Pettigrew, M. J.

2006-12-01

60

Analysis of object-stability and internal force in robotic contact tasks  

Microsoft Academic Search

The stability of an object manipulated by multiple robots (serial-link or wire-driven mechanisms) in contact tasks is investigated. We show that resultant force\\/moment applicable to the object through the contacts is represented as a polyhedral convex region in force\\/moment space. Then we propose a stability measure and a method of calculating it approximately by linear programming technique. We also present

Yusuke Maeda; Yasumichi Aiyama; Tamio Arai; Taiga Ozawa

1996-01-01

61

A new method for estimating hand internal loads from external force measurements  

Microsoft Academic Search

This study examines using force vectors measured using a directional strain gauge grip dynamometer for estimating finger flexor tendon tension. Fifty-three right-handed participants (25 males and 28 females) grasped varying-sized instrumented cylinders (2.54, 3.81, 5.08, 6.35 and 7.62 cm diameter) using a maximal voluntary power grip. The grip force vector magnitude and direction, referenced to the third metacarpal, was resolved by

C. B. Irwin; R. G. Radwin

2008-01-01

62

Freedom from Fear: International Law as a Constructive Force for Supporting American Foreign Policy  

Microsoft Academic Search

This article reveiews the history of the trend in the United States Supreme Court for the strong application of international law as a part of U.S. law. It reviews the judicial practice as well as the influence of extra-judicial factors such as exceptionalism and isolationism. This article reflects on the contemporary problems which have generated a secepticism of international law

Winston P Nagan

2012-01-01

63

PREFACE: NC-AFM 2003: Proceedings of the 6th International Conference on Non-contact Atomic Force Microscopy  

NASA Astrophysics Data System (ADS)

Direct nanoscale and atomic resolution imaging is a key issue in nanoscience and nanotechnology. The invention of the dynamic force microscope in the early 1990s was an important step forward in this direction as this instrument provides a universal tool for measuring the topography and many other physical and chemical properties of surfaces at the nanoscale. Operation in the so-called non-contact mode now allows direct atomic resolution imaging of electrically insulating surfaces and nanostructures which has been an unsolved problem during the first decade of nanotechnology. Today, we face a most rapid development of the technique and an extension of its capabilities far beyond imaging; atomically resolved force spectroscopy provides information about local binding properties and researchers now develop sophisticated schemes of force controlled atomic manipulation with the tip of the force microscope. Progress in the field of non-contact force microscopy is discussed at the annually held NC-AFM conferences that are part of a series started in 1998 with a meeting in Osaka, Japan. The 6th International Conference on Non-contact Atomic Force Microscopy took place in Dingle, Ireland, from 31 August to 3 September 2003 and this special issue is a compilation of the original publications of work presented at this meeting. The papers published here well reflect recent achievements, current trends and some of the challenging new directions in non-contact force microscopy that have been discussed during the most stimulating conference days in Dingle. Fundamental aspects of forces and dissipation relevant in imaging and spectroscopy have been covered by experimental and theoretical contributions yielding a more detailed understanding of tip--surface interaction in force microscopy. Novel and improved imaging and spectroscopy techniques have been introduced that either improve the performance of force microscopy or pave the way towards new functionalities and applications. With regard to studies on the specific systems investigated, there was a strong emphasis on oxides and ionics, as well as on organic systems. Following previous pioneering work in uncovering the atomic structure of insulating oxides with force microscopy, it was shown in the meeting that this important class of materials is now accessible for a quantitative atomic scale surface characterization. Single organic molecules and ordered organic layers are building blocks for functional nanostructures currently developed in many laboratories for applications in molecular electronics and sensor technologies. The Dingle conference impressively demonstrated that dynamic force microscopy is ready for its application as an analytical tool for these promising future nanotechnologies. The meeting was a great success scientifically and participants enjoyed the beauty of the conference site. I would like to thank all members of the international steering committee, the programme committee and the co-chairs, J Pethica, A Shluger and G Thornton, for their efforts in preparing the meeting. The members of the local organising committee, J Ballentine-Armstrong, G Cross, S Dunne, S Jarvis and Ö Özer, kept the meeting running smoothly and created a very pleasant atmosphere. The generous financial support from Science Foundation Ireland (SFI), is greatly appreciated; SFI is dramatically raising the profile of Irish science. I would also like to express my sincere gratitude to N Couzin and the journal team from Institute of Physics Publishing for their editorial management and perfect co-operation in the preparation of this special issue.

Reichling, Michael

2004-02-01

64

Late Pliocene to Pleistocene sensitivity of the Greenland Ice Sheet in response to external forcing and internal feedbacks  

NASA Astrophysics Data System (ADS)

The timing and nature of ice sheet variations on Greenland over the last ˜5 million years remain largely uncertain. Here, we use a coupled climate-vegetation-ice sheet model to determine the climatic sensitivity of Greenland to combined sets of external forcings and internal feedbacks operating on glacial-interglacial timescales. In particular, we assess the role of atmospheric pCO2, orbital forcing, and vegetation dynamics in modifying thresholds for the onset of glaciation in late Pliocene and Pleistocene. The response of circum-Arctic vegetation to declining levels of pCO2 (from 400 to 200 ppmv) and decreasing summer insolation includes a shift from boreal forest to tundra biomes, with implications for the surface energy balance. The expansion of tundra amplifies summer surface cooling and heat loss from the ground, leading to an expanded summer snow cover over Greenland. Atmospheric and land surface fields respond to forcing most prominently in late spring-summer and are more sensitive at lower Pleistocene-like levels of pCO2. We find cold boreal summer orbits produce favorable conditions for ice sheet growth, however simulated ice sheet extents are highly dependent on both background pCO2 levels and land-surface characteristics. As a result, late Pliocene ice sheet configurations on Greenland differ considerably from late Pleistocene, with smaller ice caps on high elevations of southern and eastern Greenland, even when orbital forcing is favorable for ice sheet growth.

Koenig, Sebastian J.; Deconto, Robert M.; Pollard, David

2011-09-01

65

PREDICTION OF TRUNK MUSCLE FORCES AND INTERNAL LOADS DURING FORWARD FLEXION ACTIVITIES  

Microsoft Academic Search

Knowledge of load distribution among passive and active components of the human trunk during various occupational and sportive activities is essential to assess the risk of injury and to improve prevention, evaluation, and rehabilitation of spinal disorders. To solve the trunk redundancy toward determination of muscle forces and passive loads in forward bending tasks ± loads in hands, a novel

Navid Arjmand; Aboulfazl Shirazi-Adl

66

Military Campaign Against Gangs: Internal Security Operations in the United States by Active Duty Forces.  

National Technical Information Service (NTIS)

This study examines the historical precedents and the laws that allow federal troops to combat domestic enemies, the current environment that may call for the use of active duty forces, and a model that can be used to deal with domestic disturbances withi...

D. R. Hogg

1993-01-01

67

Hazard Evaluation and Technical Assistance Report No. TA 78-30, International Center of Environmental Safety, Holloman Air Force Base, Alamogordo, New Mexico.  

National Technical Information Service (NTIS)

Animal health records, and those of current and former employees at the International Center of Environmental Safety (ICES) at Holloman Air Force Base, Alamogordo, New Mexico were reviewed in response to a request from OSHA Region VI concerning potential ...

W. J. Martone B. D. Politi

1979-01-01

68

An oblique edge crack and an internal crack in a semi-infinite plane acted on by concentrated force at arbitrary position  

Microsoft Academic Search

A semi-infinite plane with an oblique edge crack and an internal crack acted on by a pair of concentrated forces at arbitrary position is studied. The problem can be divided into two particular parts; one is the half plane with the edge crack acted on by the concentrated forces; the other is the half plane with the edge cracked subjected

Jun Qian; Norio Hasebe

1996-01-01

69

Policy lessons from comparing mortality from two global forces: international terrorism and tobacco  

Microsoft Academic Search

BACKGROUND: The aim of this study was to compare the mortality burdens from two global impacts on mortality: international terrorism and the major cause of preventable death in developed countries – tobacco use. We also sought to examine the similarities and differences between these two causes of mortality so as to better inform the policy responses directed at prevention. METHODS:

George Thomson; Nick Wilson

2005-01-01

70

Chilean Armed Forces and Their Capacity in the Context of the International Crises.  

National Technical Information Service (NTIS)

Globalization has effects on the sovereignty of nation-states due to the interdependence of the different interests involved. Nation-States are still the main actors in the international arena in the area of politics. But other actors are becoming dominan...

M. A. Quinteros

2006-01-01

71

International Body Movement Along Three Axes Resulting from Externally Applied Sinusoidal Forces.  

National Technical Information Service (NTIS)

This report presents the results of observations on the resonance frequency and damping of a number of internal visceral body structures determined when the whole body is exposed to vibrations along three axes of the body. The X-ray method used is a modif...

J. L. Nickerson M. Drazic

1966-01-01

72

Internal Body Movement Along Three Axes Resulting from Externally Applied Sinusoidal Forces.  

National Technical Information Service (NTIS)

The report presents the results of observations on the resonance frequency and damping of a number of internal visceral body structures determined when the whole body is exposed to vibrations along three axes of the body. The X-ray method used is a modifi...

J. L. Nickerson M. Drazic

1966-01-01

73

INTERNAL RESONANCE OF AN L-SHAPED BEAM WITH A LIMIT STOP: PART II, FORCED VIBRATION  

Microsoft Academic Search

A limit stop is placed at the elbow of an L-shaped beam whose linear natural frequencies are nearly commensurable. As a result of this hardening device the non-linear system exhibits multiple internal resonances, which involve various degree of coupling between the first five modes of the beam in free vibration. A point load is so placed as to excite several

D. Pun; S. L. Lau; Y. B. Liu

1996-01-01

74

Forces shaping the trends and patterns of China’s outbound international tourist flows  

Microsoft Academic Search

This study concerns itself with outbound tourist flows from China. It is informed by the interpretive social sciences paradigm, and the research methodology is qualitative and inductive in nature. The study uses secondary data analysis, case study, interview\\/questionnaire and participant observation to answer the research question “How are the trends and patterns of China’s outbound international tourist flows being shaped?”

Sze Ming Tse

2009-01-01

75

A pendulum-driven cart via internal force and static friction  

Microsoft Academic Search

In this paper, a pendulum driven cart is built using Lego robot parts. It consists of a cart with four passive wheels and a pendulum mounted on top of the cart. A DC motor is attached to the hinge joint between the cart and the pendulum which cart swing forward and backward. The cart motion is generated using its internal

Hongyi Li; Katsuhisa Furuta; Felix L. Chernousko

2005-01-01

76

Report of a workshop on nuclear forces and nonproliferation Woodrow Wilson international center for scholars, Washington, DC October 28, 2010  

SciTech Connect

A workshop sponsored by the Los Alamos National Laboratory in cooperation with the Woodrow Wilson International Center for Scholars was held at the Wilson Center in Washington, DC, on October 28, 2010. The workshop addressed evolving nuclear forces and their impacts on nonproliferation in the context of the new strategic environment, the Obama Administration's Nuclear Posture Review and the 2010 NPT Review Conference. The discussions reflected the importance of the NPR for defining the role of US nuclear forces in dealing with 21st century threats and providing guidance for National Nuclear Security Administration (NNSA) and Department of Defense (DoD) programs and, for many but not all participants, highlighted its role in the successful outcome of the NPT RevCon. There was widespread support for the NPR and its role in developing the foundations for a sustainable nuclear-weapon program that addresses nuclear weapons, infrastructure and expertise in the broader nonproliferation, disarmament and international security contexts. However, some participants raised concerns about its implementation and its long-term effectiveness and sustainability.

Pilat, Joseph F [Los Alamos National Laboratory

2010-12-08

77

A simple model of the Atlantic thermohaline circulation: Internal and forced variability with paleoclimatological implications  

NASA Astrophysics Data System (ADS)

We describe the development and application of a simple two-dimensional model of the thermohaline circulation in the Atlantic basin. The nondimensional parameters of the model consist of thermal and haline Rayleigh numbers, Lewis number, and ratios of horizontal and vertical diffusion coefficients for heat, salt, and momentum. Under mixed boundary conditions and with a convective adjustment scheme applied to represent the subgrid scale convective downwelling that drives the process of deepwater formation, the model support two modes of oscillatory behavior. One of these is on a timescale that ranges from subdecadal to decadal and appears as noisy fluctuations driven by the convective adjustment scheme. The second physical mode has a characteristic timescale of the order of centuries when the net influx of freshwater into the basin is near zero, a mode of variation which is similar to that found previously in full three-dimensional ocean general circulation model analyses of the modern circulation. We demonstrate, however, that the timescale of this physical mode is strongly dependent on the net freshwater forcing: the weaker this forcing, the shorter the timescale, the stronger the forcing, the longer the timescale. This mode therefore provides a possible explanation both for the century timescale variations observed in the modern climate record and for the millennium timescale Dansgaard-Oeschger oscillations that were characteristic of the late glacial climate state. The response of the model to freshwater anomalies similar to those known to have developed during the late glacial state of the ice age and during deglaciation seems to provide a straightforward explanation of the climatic variations recently revealed in ?18O time series for ice cores drilled at Summit, Greenland. This is especially true of the experiments that we have performed in an effort to better understand the Younger-Dryas type climatic fluctuations that occurred during the late glacial and the last deglaciation periods. Our experiments strongly support the hypothesis that the Atlantic thermohaline circulation played a very important role in these intense events.

Sakai, K.; Peltier, W. R.

1995-07-01

78

Atmospheric impacts of Arctic sea-ice loss, 1979-2009: separating forced change from atmospheric internal variability  

NASA Astrophysics Data System (ADS)

The ongoing loss of Arctic sea-ice cover has implications for the wider climate system. The detection and importance of the atmospheric impacts of sea-ice loss depends, in part, on the relative magnitudes of the sea-ice forced change compared to natural atmospheric internal variability (AIV). This study analyses large ensembles of two independent atmospheric general circulation models in order to separate the forced response to historical Arctic sea-ice loss (1979-2009) from AIV, and to quantify signal-to-noise ratios. We also present results from a simulation with the sea-ice forcing roughly doubled in magnitude. In proximity to regions of sea-ice loss, we identify statistically significant near-surface atmospheric warming and precipitation increases, in autumn and winter in both models. In winter, both models exhibit a significant lowering of sea level pressure and geopotential height over the Arctic. All of these responses are broadly similar, but strengthened and/or more geographically extensive, when the sea-ice forcing is doubled in magnitude. Signal-to-noise ratios differ considerably between variables and locations. The temperature and precipitation responses are significantly easier to detect (higher signal-to-noise ratio) than the sea level pressure or geopotential height responses. Equally, the local response (i.e., in the vicinity of sea-ice loss) is easier to detect than the mid-latitude or upper-level responses. Based on our estimates of signal-to-noise, we conjecture that the local near-surface temperature and precipitation responses to past Arctic sea-ice loss exceed AIV and are detectable in observed records, but that the potential atmospheric circulation, upper-level and remote responses may be partially or wholly masked by AIV.

Screen, James A.; Deser, Clara; Simmonds, Ian; Tomas, Robert

2013-06-01

79

Treating rheumatoid arthritis to target: recommendations of an international task force  

PubMed Central

Background Aiming at therapeutic targets has reduced the risk of organ failure in many diseases such as diabetes or hypertension. Such targets have not been defined for rheumatoid arthritis (RA). Objective To develop recommendations for achieving optimal therapeutic outcomes in RA. Methods A task force of rheumatologists and a patient developed a set of recommendations on the basis of evidence derived from a systematic literature review and expert opinion; these were subsequently discussed, amended and voted upon by >60 experts from various regions of the world in a Delphi-like procedure. Levels of evidence, strength of recommendations and levels of agreement were derived. Results The treat-to-target activity resulted in 10 recommendations. The treatment aim was defined as remission with low disease activity being an alternative goal in patients with long-standing disease. Regular follow-up (every 1–3 months during active disease) with appropriate therapeutic adaptation to reach the desired state within 3 to a maximum of 6 months was recommended. Follow-up examinations ought to employ composite measures of disease activity which include joint counts. Additional items provide further details for particular aspects of the disease. Levels of agreement were very high for many of these recommendations (?9/10). Conclusion The 10 recommendations are supposed to inform patients, rheumatologists and other stakeholders about strategies to reach optimal outcomes of RA based on evidence and expert opinion.

Smolen, Josef S; Aletaha, Daniel; Bijlsma, Johannes W J; Breedveld, Ferdinand C; Boumpas, Dimitrios; Burmester, Gerd; Combe, Bernard; Cutolo, Maurizio; de Wit, Maarten; Dougados, Maxime; Emery, Paul; Gibofsky, Alan; Gomez-Reino, Juan Jesus; Haraoui, Boulos; Kalden, Joachim; Keystone, Edward C; Kvien, Tore K; McInnes, Iain; Martin-Mola, Emilio; Montecucco, Carlomaurizio; Schoels, Monika; van der Heijde, Desiree

2010-01-01

80

Preventing nuclear terrorism: the report and papers of the International Task Force on Prevention of Nuclear Terrorism  

SciTech Connect

The International Task Force on Prevention of Nuclear Terrorism, formed in 1985 under the Nuclear Control Institute, commissioned 26 studies and produced an extensive report on the problem and prevention of nuclear terrorism, Part I of this book is the full report, and part II contains the individual studies under two section: (A) Defining the Threat (8 studies); and (B) Strategies for Dealing with the Threat (18 studies). Detailed recommendations are made, in many of the studies, for better protection of nuclear weapons, materials, and facilities; greater cooperation among national intelligence agencies; tighter controls on nuclear transfers; more effective arms control initiatives; and emergency management programs. A separate abstract was prepared for the report and each of the 26 studies.

Leventhal, P.; Alexander, Y. (eds.)

1987-01-01

81

Development of a new physics-based internal coordinate mechanics force field (ICMFF) and its application to protein loop modeling  

PubMed Central

We report the development of ICMFF, new force field parameterized using a combination of experimental data for crystals of small molecules and quantum mechanics calculations. The main features of ICMFF include: (a) parameterization for the dielectric constant relevant to the condensed state (?=2) instead of vacuum; (b) an improved description of hydrogen-bond interactions using duplicate sets of van der Waals parameters for heavy atom-hydrogen interactions; and (c) improved backbone covalent geometry and energetics achieved using novel backbone torsional potentials and inclusion of the bond angles at the C? atoms into the internal variable set. The performance of ICMFF was evaluated through loop modeling simulations for 4-13 residue loops. ICMFF was combined with a solvent-accessible surface area solvation model optimized using a large set of loop decoys. Conformational sampling was carried out using the Biased Probability Monte Carlo method. Average/median backbone root-mean-square deviations of the lowest energy conformations from the native structures were 0.25/0.21 Å for 4 residues loops, 0.84/0.46 Å for 8 residue loops, and 1.16/0.73 Å for 12 residue loops. To our knowledge, these results are significantly better than or comparable to those reported to date for any loop modeling method that does not take crystal packing into account. Moreover, the accuracy of our method is on par with the best previously reported results obtained considering the crystal environment. We attribute this success to the high accuracy of the new ICM force field achieved by meticulous parameterization, to the optimized solvent model, and the efficiency of the search method.

Arnautova, Yelena A.; Abagyan, Ruben A.

2010-01-01

82

Computation of the internal forces in cilia: application to ciliary motion, the effects of viscosity, and cilia interactions.  

PubMed Central

This paper presents a simple and reasonable method for generating a phenomenological model of the internal mechanism of cilia. The model uses a relatively small number of parameters whose values can be obtained by fitting to ciliary beat shapes. Here, we use beat patterns observed in Paramecium. The forces that generate these beats are computed and fit to a simple functional form called the "engine." This engine is incorporated into a recently developed hydrodynamic model that accounts for interactions between neighboring cilia and between the cilia and the surface from which they emerge. The model results are compared to data on ciliary beat patterns of Paramecium obtained under conditions where the beats are two-dimensional. Many essential features of the motion, including several properties that are not built in explicitly, are shown to be captured. In particular, the model displays a realistic change in beat pattern and frequency in response to increased viscosity and to the presence of neighboring cilia in configurations such as rows of cilia and two-dimensional arrays of cilia. We found that when two adjacent model cilia start beating at different phases they become synchronized within several beat periods, as observed in experiments where two flagella are brought into close proximity. Furthermore, examination of various multiciliary configurations shows that an approximately antiplectic wave pattern evolves autonomously. This modeling evidence supports earlier conjectures that metachronism may occur, at least partially, as a self-organized phenomenon due to hydrodynamic interactions between neighboring cilia.

Gueron, S; Levit-Gurevich, K

1998-01-01

83

International Quick Response Forces.  

National Technical Information Service (NTIS)

Increasing in number and complexity over the past five years, the UN's peacekeeping efforts have met with mixed success. The search for more effective multilateral ways to preserve peace and promote regional stability leads to consideration of an internat...

G. J. Murphy

1994-01-01

84

The relative contributions of radiative forcing and internal climate variability to the late 20th Century winter drying of the Mediterranean region  

NASA Astrophysics Data System (ADS)

The roles of anthropogenic climate change and internal climate variability in causing the Mediterranean region's late 20th Century extended winter drying trend are examined using 19 coupled models from the Intergovernmental Panel on Climate Change Fourth Assessment Report. The observed drying was influenced by the robust positive trend in the North Atlantic Oscillation (NAO) from the 1960s to the 1990s. Model simulations and observations are used to assess the probable relative roles of radiative forcing, and internal variability in explaining the circulation trend that drove much of the precipitation change. Using the multi-model ensemble we assess how well the models can produce multidecadal trends of realistic magnitude, and apply signal-to-noise maximizing EOF analysis to obtain a best estimate of the models' (mean) sea-level pressure (SLP) and precipitation responses to changes in radiative forcing. The observed SLP and Mediterranean precipitation fields are regressed onto the timeseries associated with the models' externally forced pattern and the implied linear trends in both fields between 1960 and 1999 are calculated. It is concluded that the radiatively forced trends are a small fraction of the total observed trends. Instead it is argued that the robust trends in the observed NAO and Mediterranean rainfall during this period were largely due to multidecadal internal variability with a small contribution from the external forcing. Differences between the observed and NAO-associated precipitation trends are consistent with those expected as a response to radiative forcing. The radiatively forced trends in circulation and precipitation are expected to strengthen in the current century and this study highlights the importance of their contribution to future precipitation changes in the region.

Kelley, Colin; Ting, Mingfang; Seager, Richard; Kushnir, Yochanan

2012-05-01

85

Subthalamic nucleus and internal globus pallidus scale with the rate of change of force production in humans  

Microsoft Academic Search

The basal ganglia, motor cortex, and cerebellum have been implicated as a circuit that codes for movement velocity. Since movement velocity covaries with the magnitude of force exerted and previous studies have shown that similar regions scale in activation for velocity and force, the scaling of neuronal activity with movement velocity could be due to the force exerted. The present

David E. Vaillancourt; Mary A. Mayka; Keith R. Thulborn; Daniel M. Corcos

2004-01-01

86

A review of a method for dynamic load distribution, dynamical modeling, and explicit internal force control when two manipulators mutually lift and transport a rigid body object  

SciTech Connect

The paper reviews a method for modeling and controlling two serial link manipulators which mutually lift and transport a rigid body object in a three dimensional workspace. A new vector variable is introduced which parameterizes the internal contact force controlled degrees of freedom. A technique for dynamically distributing the payload between the manipulators is suggested which yields a family of solutions for the contact forces and torques the manipulators impart to the object. A set of rigid body kinematic constraints which restrict the values of the joint velocities of both manipulators is derived. A rigid body dynamical model for the closed chain system is first developed in the joint space. The model is obtained by generalizing the previous methods for deriving the model. The joint velocity and acceleration variables in the model are expressed in terms of independent pseudovariables. The pseudospace model is transformed to obtain reduced order equations of motion and a separate set of equations governing the internal components of the contact forces and torques. A theoretic control architecture is suggested which explicitly decouples the two sets of equations comprising the model. The controller enables the designer to develop independent, non-interacting control laws for the position control and internal force control of the system.

Unseren, M.A.

1997-04-20

87

International.  

ERIC Educational Resources Information Center

|The International Geological Correlation Project has attained scientific maturity and broad support and participation by geologists world wide. Its purpose is to provide a mechanism for international cooperation and information exchange about geological problems that transcend national boundaries. (Author/BB)|

Hoover, Linn

1979-01-01

88

PREFACE: NC-AFM 2006: Proceedings of the 9th International Conference on Non-contact Atomic Force Microscopy  

NASA Astrophysics Data System (ADS)

The advent of scanning probe microscopy (SPM) in the 1980s has significantly promoted nanoscience and nanotechnology. In particular, non-contact atomic force microscopy (NC-AFM), one of the SPM family, has unique capabilities with high spatial resolution for nanoscale measurements in vacuum, air and liquids. In the last decade we have witnessed the rapid progress of NC-AFM with improved performance and increasing applications. A series of NC-AFM international conferences have greatly contributed to this field. Initiated in Osaka in 1998, the NC-AFM meeting has been followed by annual conferences at Pontresina, Hamburg, Kyoto, Montreal, Dingle, Seattle and Bad Essen. The 9th conference was held in Kobe, Japan, 16-20 July 2006. This special issue of Nanotechnology contains the outstanding contributions of the conference. During the meeting delegates learnt about a number of significant advances. Topics covered atomic resolution imaging of metals, semiconductors, insulators, ionic crystals, oxides, molecular systems, imaging of biological materials in various environments and novel instrumentation. Work also included the characterization of electronic and magnetic properties, tip and cantilever fabrication and characterization, atomic distinction based on analysis of tip-sample interaction, atomic scale manipulation, fabrication of nanostructures using NC-AFM, and related theories and simulations. We are greatly impressed by the increasing number of applications, and convinced that NC-AFM and related techniques are building a bridge to a future nano world, where quantum phenomena will dominate and nano devices will be realized. In addition, a special session on SPM road maps was held as a first trial in the field, where the future prospects of SPM were discussed enthusiastically. The overall success of the NC-AFM 2006 conference was due to the efforts of many individuals and groups with respect to scientific and technological progress, as well as the international exchange among participants. We hope that all of the participants enjoyed the activities of the conference and the town of Kobe. We are indebted to the members of the international steering committee and the local organizing committee for this successful conference. The operation of conference business by the Kobe Convention and Visitors Association, and by the staff in Professor Morita's lab in Osaka University, and Professor Onishi's lab in Kobe University, is greatly acknowledged. We would like to express our sincere gratitude to the 167th committee on Nano-probe Technology of Japan Society for the Promotion of Science, Nanotechnology Researchers Network Center of Japan, Foundation Advanced Technology Institute, Tsutomu Nakauchi Foundation, and all of the exhibitors at the conference for their financial support. The funding from Kobe Advanced ICT Research Center, National Institute of Information and Communications Technology, is greatly appreciated and enabled these proceedings to be published by IOP Publishing (IOP). We also thank the editorial staff of IOP for their professional work in publishing this special issue.

Tomitori, Masahiko; Onishi, Hiroshi

2007-02-01

89

Semidirect radiative forcing of internal mixed black carbon cloud droplet and its regional climatic effect over China  

Microsoft Academic Search

Black carbon (BC) is one of the most important atmospheric aerosols. It can exert a positive radiative forcing by absorbing solar radiation and a negative radiative forcing by acting as cloud condensation nuclei (CCN) at the top of the atmosphere (TOA). Furthermore, cloud droplets with BC can absorb more solar radiation and reduce their single-scattering albedo (SSA), leading to a

B. L. Zhuang; L. Liu; F. H. Shen; T. J. Wang; Y. Han

2010-01-01

90

PREFACE: NC-AFM 2005: Proceedings of the 8th International Conference on Non-Contact Atomic Force Microscopy  

NASA Astrophysics Data System (ADS)

The 8th International Conference on Non-Contact Atomic Force Microscopy, held in Bad Essen, Germany, from 15?18th August 2005, attracted a record breaking number of participants presenting excellent contributions from a variety of scientific fields. This clearly demonstrated the high level of activity and innovation present in the community of NC-AFM researchers and the continuous growth of the field. The strongest ever participation of companies for a NC-AFM meeting is a sign for the emergence of new markets for the growing NC-AFM community; and the high standard of the products presented at the exhibition, many of them brand-new developments, reflected the unbroken progress in technology. The development of novel technologies and the sophistication of known techniques in research laboratories and their subsequent commercialization is still a major driving force for progress in this area of nanoscience. The conference was a perfect demonstration of how progress in the development of enabling technologies can readily be transcribed into basic research yielding fundamental insight with an impact across disciplines. The NC-AFM 2005 scientific programme was based on five cornerstones, each representing an area of vivid research and scientific progress. Atomic resolution imaging on oxide surfaces, which has long been a vision for the catalysis community, appears to be routine in several laboratories and after a period of demonstrative experiments NC-AFM now makes unique contributions to the understanding of processes in surface chemistry. These capabilities also open up new routes for the analysis of clusters and molecules deposited on dielectric surfaces where resolution limits are pushed towards the single atom level. Atomic precision manipulation with the dynamic AFM left the cradle of its infancy and flourishes in the family of bottom-up fabrication nanotechnologies. The systematic development of established and the introduction of new concepts of contrast formation allow the highly resolved measurement of a number of physical properties far beyond the determination of surface topography. The development of techniques allowing atomic resolution dynamic mode imaging in liquids pushes the door open for an atomic precision analysis of biological samples under physiological conditions. In each of these fields, the conference demonstrated cutting-edge results and also provided perspectives for the next steps on the roadmap of NC-AFM towards the development of its full extent. The conference in Bad Essen was made possible by the continuous dedication of the local management and we are most grateful to Frauke Riemann, Joachim Fontaine and the members of the supporting team for the smooth organization. We gratefully appreciate the financial support of the exhibitors, namely Anfatec, HALCYONICS, JEOL, LOT-Oriel, NanoMagnetics, NT-MDT, Omicron, Schaefer Technology, SURFACE, UNISOKU and the local sponsors which enabled us to provide free participation at the conference for ten promising young researchers who had submitted excellent contributions. It was a great pleasure for us to continue our most successful collaboration with Nanotechnology as our partner for the proceedings publication and we would like to thank Ian Forbes and the publishing team for the professional handling of the peer review and all production matters.

Reichling, M.; Mikosch, W.

2006-04-01

91

Compensation and Staffing Levels of the FAA (Federal Aviation Administration) Police Force at Washington National and Washington Dulles International Airports.  

National Technical Information Service (NTIS)

GAO was requested to evaluate compensation and staffing levels of the Federal Aviation Administration (FAA) police force at National and Dulles airports and to determine if lower pay for FAA police was contributing to the airports' recruitment and retenti...

1985-01-01

92

International Policing and International Relations  

Microsoft Academic Search

The idea of creating an international police force (IPF) was first mooted by Lord David Davies in the 1930s. In 1963 U Thant, Secretary General of the United Nations, then claimed that he had ‘no doubt that the world should eventually have an international police force’. Yet our international system has been and continues to be based on states, their

B. K. Greener

2012-01-01

93

Report of a Workshop in Nuclear Forces and Nonproliferation held at the Woodrow Wilson International Center for Scholars, Washington, DC  

Microsoft Academic Search

The workshop addressed evolving nuclear forces and their impacts on nonproliferation in the context of the new strategic environment, the Obama Administration's Nuclear Posture Review (NPR) Review and the 2010 Conference (RevCon) of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). The issues discussed are at the heart of the debate on nuclear policy issues such

Pilat; Joseph F

2009-01-01

94

PREFACE: NC-AFM 2003: Proceedings of the 6th International Conference on Non-contact Atomic Force Microscopy  

Microsoft Academic Search

Direct nanoscale and atomic resolution imaging is a key issue in nanoscience and nanotechnology. The invention of the dynamic force microscope in the early 1990s was an important step forward in this direction as this instrument provides a universal tool for measuring the topography and many other physical and chemical properties of surfaces at the nanoscale. Operation in the so-called

Michael Reichling

2004-01-01

95

Internal force calculation and stability analysis of the slope reinforced by pre-stressed anchor cables and frame beams  

Microsoft Academic Search

In order to study the force distribution law in the slopes reinforced by pre-stressed anchor cables and frame beams, optimization safety factor calculation method of slopes after reinforcement, the load applied by anchor cables via frame beams is considered as line load on the slope, and we could obtain theoretical solution of additional stress in the slope by means of

Zhou Zhi-Gang; Gong Xiao-Nan; Li Ying

2011-01-01

96

International terrorism as a force of homogenization? A constructivist approach to understanding cross-national threat perceptions and responses  

Microsoft Academic Search

Has the emergence of international jihadist terrorism led to common threat perceptions and responses in Europe? The article argues that the homogenization thesis is based around a misguided functionalist notion of a single ‘optimal response’ to an alleged new and potentially catastrophic kind of threat with uniform consequences for all ‘Western’ countries. Drawing on insights from different bodies of literature,

Christoph O Meyer

2009-01-01

97

Electronics goes halogen-free: international driving forces and the availability and potential of halogen-free alternatives  

Microsoft Academic Search

The electronics and electrical industry and their suppliers are facing an increasing need to find halogen-free alternatives to flame retardancy in their products due to legislative actions and market pressure. In order to support development of corporate actions, “The International project on Flame Retardancy in Electronics-Conceptual Study”, has been carried out by IVF in co-operation with 12 major European and

C. G. Bergendahl

2000-01-01

98

Evaluation of the meteorological forcing used for the Air Quality Model Evaluation International Initiative (AQMEII) air quality simulations  

NASA Astrophysics Data System (ADS)

Accurate regional air pollution simulation relies strongly on the accuracy of the mesoscale meteorological simulation used to drive the air quality model. The framework of the Air Quality Model Evaluation International Initiative (AQMEII), which involved a large international community of modeling groups in Europe and North America, offered a unique opportunity to evaluate the skill of mesoscale meteorological models for two continents for the same period. More than 20 groups worldwide participated in AQMEII, using several meteorological and chemical transport models with different configurations. The evaluation has been performed over a full year (2006) for both continents. The focus for this particular evaluation was meteorological parameters relevant to air quality processes such as transport and mixing, chemistry, and surface fluxes. The unprecedented scale of the exercise (one year, two continents) allowed us to examine the general characteristics of meteorological models’ skill and uncertainty. In particular, we found that there was a large variability between models or even model versions in predicting key parameters such as surface shortwave radiation. We also found several systematic model biases such as wind speed overestimations, particularly during stable conditions. We conclude that major challenges still remain in the simulation of meteorology, such as nighttime meteorology and cloud/radiation processes, for air quality simulation.

Vautard, Robert; Moran, Michael D.; Solazzo, Efisio; Gilliam, Robert C.; Matthias, Volker; Bianconi, Roberto; Chemel, Charles; Ferreira, Joana; Geyer, Beate; Hansen, Ayoe B.; Jericevic, Amela; Prank, Marje; Segers, Arjo; Silver, Jeremy D.; Werhahn, Johannes; Wolke, Ralf; Rao, S. T.; Galmarini, Stefano

2012-06-01

99

Use of induced acceleration to quantify the (de)stabilization effect of external and internal forces on postural responses.  

PubMed

Due to the mechanical coupling between the body segments, it is impossible to see with the naked eye the causes of body movements and understand the interaction between movements of different body parts. The goal of this paper is to investigate the use of induced acceleration analysis to reveal the causes of body movements. We derive the analytical equations to calculate induced accelerations and evaluate its potential to study human postural responses to support-surface translations. We measured the kinematic and kinetic responses of a subject to sudden forward and backward translations of a moving platform. The kinematic and kinetics served as input to the induced acceleration analyses. The induced accelerations showed explicitly that the platform acceleration and deceleration contributed to the destabilization and restabilization of standing balance, respectively. Furthermore, the joint torques, coriolis and centrifugal forces caused by swinging of the arms, contributed positively to stabilization of the Center of Mass. It is concluded that induced acceleration analyses is a valuable tool in understanding balance responses to different kinds of perturbations and may help to identify the causes of movement in different pathologies. PMID:18075045

van Asseldonk, Edwin H F; Carpenter, Mark G; van der Helm, Frans C T; van der Kooij, Herman

2007-12-01

100

Diabetes mellitus in older people: position statement on behalf of the International Association of Gerontology and Geriatrics (IAGG), the European Diabetes Working Party for Older People (EDWPOP), and the International Task Force of Experts in Diabetes.  

PubMed

Diabetes mellitus is a highly prevalent metabolic condition in ageing societies associated with high levels of morbidity, multiple therapies, and functional deterioration that challenges even the best of health care systems to deliver high-quality, individualized care. Most international clinical guidelines have ignored the often-unique issues of frailty, functional limitation, changes in mental health, and increasing dependency that characterize many aged patients with diabetes. A collaborative Expert Group of the IAGG and EDWPOP and an International Task Force have explored the key issues that affect diabetes in older people using a robust method comprising a Delphi process and an evidence-based review of the literature. Eight domains of interest were initially agreed and discussed: hypoglycemia, therapy, care home diabetes, influence of comorbidities, glucose targets, family/carer perspectives, diabetes education, and patient safety. A set of "consensus" statements was produced in each domain of interest. These form a foundation for future policy development in this area and should influence the clinical behavior and approach of all health professionals engaged in delivering diabetes care to older people. PMID:22748719

Sinclair, Alan; Morley, John E; Rodriguez-Mañas, Leo; Paolisso, Giuseppe; Bayer, Tony; Zeyfang, Andrej; Bourdel-Marchasson, Isabelle; Vischer, Ulrich; Woo, Jean; Chapman, Ian; Dunning, Trisha; Meneilly, Graydon; Rodriguez-Saldana, Joel; Gutierrez Robledo, Luis Miguel; Cukierman-Yaffe, Tali; Gadsby, Roger; Schernthaner, Guntram; Lorig, Kate

2012-07-01

101

Electrodynamic force law controversy  

NASA Astrophysics Data System (ADS)

Cavalleri et al. [Phys. Rev. E 52, 2505 (1998); Eur. J. Phys. 17, 205 (1996)] have attempted to resolve the electrodynamic force law controversy. This attempt to prove the validity of either the Ampère or Lorentz force law by theory and experiment has revealed only that the two are equivalent when predicting the force on part of a circuit due to the current in the complete circuit. However, in our analysis of internal stresses, only Ampère's force law agrees with experiment.

Graneau, Peter; Graneau, Neal

2001-05-01

102

Criteria for evaluation of disease extent by 123I-metaiodobenzylguanidine scans in neuroblastoma: a report for the International Neuroblastoma Risk Group (INRG) Task Force  

PubMed Central

Background: Neuroblastoma is an embryonic tumour of the sympathetic nervous system, metastatic in half of the patients at diagnosis, with a high preponderance of osteomedullary disease, making accurate evaluation of metastatic sites and response to therapy challenging. Metaiodobenzylguanidine (mIBG), taken into cells via the norepinephrine transporter, provides a sensitive and specific method of assessing tumour in both soft tissue and bone sites. The goal of this report was to develop consensus guidelines for the use of mIBG scans in staging, response assessment and surveillance in neuroblastoma. Methods: The International Neuroblastoma Risk Group (INRG) Task Force, including a multidisciplinary group in paediatric oncology of North and South America, Europe, Oceania and Asia, formed a subcommittee on metastatic disease evaluation, including expert nuclear medicine physicians and oncologists, who developed these guidelines based on their experience and the medical literature, with approval by the larger INRG Task Force. Results: Guidelines for patient preparation, radiotracer administration, techniques of scanning including timing, energy, specific views, and use of single photon emission computed tomography are included. Optimal timing of scans in relation to therapy and for surveillance is reviewed. Validated semi-quantitative scoring methods in current use are reviewed, with recommendations for use in prognosis and response evaluation. Conclusions: Metaiodobenzylguanidine scans are the most sensitive and specific method of staging and response evaluation in neuroblastoma, particularly when used with a semi-quantitative scoring method. Use of the optimal techniques for mIBG in staging and response, including a semi-quantitative score, is essential for evaluation of the efficacy of new therapy.

Matthay, K K; Shulkin, B; Ladenstein, R; Michon, J; Giammarile, F; Lewington, V; Pearson, A D J; Cohn, S L

2010-01-01

103

A review of a method for dynamic load distribution, dynamic modeling, and explicit internal force control when two serial link manipulators mutually lift and transport a rigid body object  

Microsoft Academic Search

The report reviews a method for modeling and controlling two serial link manipulators which mutually lift and transport a rigid body object in a three dimensional workspace. A new vector variable is introduced which parameterizes the internal contact force controlled degrees of freedom. A technique for dynamically distributing the payload between the manipulators is suggested which yields a family of

Unseren

1997-01-01

104

Drag force acting on a neuromast in the fish lateral line trunk canal. I. Numerical modelling of external-internal flow coupling  

PubMed Central

Fishes use a complex, multi-branched, mechanoreceptive organ called the lateral line to detect the motion of water in their immediate surroundings. This study is concerned with a subset of that organ referred to as the lateral line trunk canal (LLTC). The LLTC consists of a long tube no more than a few millimetres in diameter embedded immediately under the skin of the fish on each side of its body. In most fishes, pore-like openings are regularly distributed along the LLTC, and a minute sensor enveloped in a gelatinous cupula, referred to as a neuromast, is located between each pair of pores. Drag forces resulting from fluid motions induced inside the LLTC by pressure fluctuations in the external flow stimulate the neuromasts. This study, Part I of a two-part sequence, investigates the motion-sensing characteristics of the LLTC and how it may be used by fishes to detect wakes. To this end, an idealized geometrical/dynamical situation is examined that retains the essential problem physics. A two-level numerical model is developed that couples the vortical flow outside the LLTC to the flow stimulating the neuromasts within it. First, using a Navier–Stokes solver, we calculate the unsteady flow past an elongated rectangular prism and a fish downstream of it, with both objects moving at the same speed. By construction, the prism generates a clean, periodic vortex street in its wake. Then, also using the Navier–Stokes solver, the pressure field associated with this external flow is used to calculate the unsteady flow inside the LLTC of the fish, which creates the drag forces acting on the neuromast cupula. Although idealized, this external–internal coupled flow model allows an investigation of the filtering properties and performance characteristics of the LLTC for a range of frequencies of biological interest. The results obtained here and in Part II show that the LLTC acts as a low-pass filter, preferentially damping high-frequency pressure gradient oscillations, and hence high-frequency accelerations, associated with the external flow.

Barbier, Charlotte; Humphrey, Joseph A.C.

2008-01-01

105

A review of a method for dynamic load distribution, dynamic modeling, and explicit internal force control when two serial link manipulators mutually lift and transport a rigid body object  

SciTech Connect

The report reviews a method for modeling and controlling two serial link manipulators which mutually lift and transport a rigid body object in a three dimensional workspace. A new vector variable is introduced which parameterizes the internal contact force controlled degrees of freedom. A technique for dynamically distributing the payload between the manipulators is suggested which yields a family of solutions for the contact forces and torques the manipulators impart to the object. A set of rigid body kinematic constraints which restricts the values of the joint velocities of both manipulators is derived. A rigid body dynamical model for the closed chain system is first developed in the joint space. The model is obtained by generalizing the previous methods for deriving the model. The joint velocity and acceleration variables in the model are expressed in terms of independent pseudovariables. The pseudospace model is transformed to obtain reduced order equations of motion and a separate set of equations governing the internal components of the contact forces and torques. A theoretic control architecture is suggested which explicitly decouples the two sets of equations comprising the model. The controller enables the designer to develop independent, non-interacting control laws for the position control and internal force control of the system.

Unseren, M.A.

1997-09-01

106

Consequences of forced silking.  

PubMed

The forced silking of a spider to obtain major ampullate (MA) silk for experiments is a standard practice; however, this method may have profound effects on the resulting silk's properties. Experiments were performed to determine the magnitude of the difference in the forces required to draw silk from the MA gland between unrestrained spiders descending on their draglines and restrained spiders from which MA silk was drawn with a motor. The results show that freely falling spiders can spool silk with as little as 0.1 body weights of force, which generates a stress that is about 2% of the silk's tensile strength. In contrast, forcibly silked spiders apply as much as 4 body weights of force with an internal braking mechanism, and this force creates silk stresses in excess of 50% of the silk's tensile strength. The large forces observed in forced silking should strongly affect the draw alignment of the polymer network in the newly spun fibers, and this may account for the differences in material properties observed between naturally spun and forcibly spun MA silks. In addition, the heat produced by the internal friction brake during forced silking may set the upper limit of forced silking speed. PMID:15132653

Ortlepp, Christine S; Gosline, John M

107

Basic Education in Developing Countries. Hearing before the International Task Force of the Select Committee on Hunger. House of Representatives, One Hundredth Congress, First Session.  

ERIC Educational Resources Information Center

The responsibility of the U.S. House of Representatives Task Force on Hunger is to investigate the causes and dimensions of world hunger and to develop legislative recommendations addressing the issues raised. At this hearing, the issue discussed was of basic education as a crucial link in expanding opportunities for poor and hungry people to…

Congress of the U.S., Washington, DC. House Select Committee on Hunger.

108

EULAR recommendations for the management of knee osteoarthritis: report of a task force of the Standing Committee for International Clinical Studies Including Therapeutic Trials (ESCISIT)  

Microsoft Academic Search

BACKGROUNDOsteoarthritis (OA) is the most common joint disease encountered throughout Europe. A task force for the EULAR Standing Committee for Clinical Trials met in 1998 to determine the methodological and logistical approach required for the development of evidence based guidelines for treatment of knee OA. The guidelines were restricted to cover all currently available treatments for knee OA diagnosed either

A Pendleton; N Arden; M Dougados; M Doherty; B Bannwarth; J W J Bijlsma; F Cluzeau; C Cooper; P A Dieppe; K-P Günther; H J Hauselmann; G Herrero-Beaumont; P M Kaklamanis; B Leeb; M Lequesne; S Lohmander; B Mazieres; E-M Mola; K Pavelka; U Serni; B Swoboda; A A Verbruggen; G Weseloh; I Zimmermann-Gorska

2000-01-01

109

Business and Education for World Affairs. A Report of the Business Task Force to the International Education Year Committee of the U.S. National Commission for UNESCO.  

ERIC Educational Resources Information Center

A Business Task Force was appointed by the U.S. National Commission for UNESCO with a specific mission of examining ways in which corporations, collegiate schools of business, and business organizations could most effectively encourage improvement of education, especially programs to prepare businessmen to assume new roles and responsibilities…

National Commission for UNESCO (Dept. of State), Washington, DC.

110

Internal Gravity Waves in an Atmosphere with Wind Shear: Validity of the WKB Approximation at Critical Layers in the Presence of Buoyancy Forces  

Microsoft Academic Search

The application of the WKB method to internal gravity waves in a compressible fluid with wind shear is studied from the standpoint of dispersion and of the validity of the method. It is shown that at resonance (the level where the phase speed is Doppler-shifted to zero) the validity is dependent only on the local Richardson number; we accept as

R. C. Whitten; C. A. Riegel

1973-01-01

111

Internal vs. external forcing in shallow marine diatreme formation: A case study from the Iblean Mountains (SE-Sicily, Central Mediterranean)  

Microsoft Academic Search

A model of diatreme evolution in a shallow marine setting is based on a multi-disciplinary analysis of diatremes in the Iblean Mountains (Sicily). The approach includes stratigraphic, volcanological, structural, petrologic and compositional data. We invoke a complex interplay of internal (rapid ascent and pyroclastic fragmentation of a volatile (CO2)-rich nephelinitic magma at depth) and external factors. These comprise hydroclastic explosions

Ines Suiting; Hans-Ulrich Schmincke

2009-01-01

112

Good Research Practices for Measuring Drug Costs in Cost-Effectiveness Analyses:An International Perspective: The ISPOR Drug CostTask Force Report—PartVI  

Microsoft Academic Search

Objective: The pharmacoeconomic guidelines available in the literature or promulgated in many countries are either vague or silent about how drug costs should be established or measured so an international comparison of cost-effectiveness analysis (CEA) results can be made. The objective of this report is to provide guidance and recommendations on how drug costs should be measured for CEAs done

Lizheng Shi; Meredith Hodges; Michael Drummond; Jeonghoon Ahn; Shu Chuen Li; Shanlian Hu; Federico Augustovski; Joel W. Hay; Jim Smeeding

113

Centripetal Force  

NSDL National Science Digital Library

This activity is inquiry because students should not yet know the equation for centripetal force. Although they will not exactly derive the equation from this lab, they will determine that there is a direct relationship between force, mass, and velocity,

Horton, Michael

2009-05-30

114

Nuclear forces  

NASA Astrophysics Data System (ADS)

These lectures present an introduction into the theory of nuclear forces. We focus mainly on the modern approach, in which the forces between nucleons emerge from low-energy QCD via chiral effective field theory.

Machleidt, R.

2013-06-01

115

The persistence length of DNA is reached from the persistence length of its null isomer through an internal electrostatic stretching force.  

PubMed

To understand better the effect of electrostatics on the rigidity of the DNA double helix, we define DNA*, the null isomer of DNA, as the hypothetical structure that would result from DNA if its phosphate groups were not ionized. For the purposes of theoretical analysis, we model DNA* as identical to ordinary DNA but supplemented by a longitudinal compression force equal in magnitude but oppositely directed to the stretching (tension) force on DNA caused by phosphate-phosphate repulsions. The null isomer DNA* then becomes an elastically buckled form of fully ionized DNA. On this basis, we derive a nonadditive relationship between the persistence length P of DNA and the persistence length P* of its null isomer. From the formula obtained we can predict the value of P* if P is known, and we can predict the ionic strength dependence of P under the assumption that P* does not depend on ionic strength. We predict a value of P* for null DNA drastically lower than the value of P for DNA in its ordinary state of fully ionized phosphates. The predicted dependence of P on salt concentration is log-c over most of the concentration range, with no tendency toward a salt-independent value in the range of validity of the theory. The predictions are consistent with much of the persistence-length data available for DNA. Alternate theories of the Odijk-Skolnik-Fixman type, including one by the author, are considered skeptically on the grounds that the underlying model may not be realistic. Specifically, we doubt the accuracy for real polyelectrolytes of the Odijk-Skolnik-Fixman assumption that the polymer structure is invariant to changes in electrostatic forces. PMID:16935960

Manning, Gerald S

2006-08-25

116

The Persistence Length of DNA Is Reached from the Persistence Length of Its Null Isomer through an Internal Electrostatic Stretching Force  

PubMed Central

To understand better the effect of electrostatics on the rigidity of the DNA double helix, we define DNA*, the null isomer of DNA, as the hypothetical structure that would result from DNA if its phosphate groups were not ionized. For the purposes of theoretical analysis, we model DNA* as identical to ordinary DNA but supplemented by a longitudinal compression force equal in magnitude but oppositely directed to the stretching (tension) force on DNA caused by phosphate-phosphate repulsions. The null isomer DNA* then becomes an elastically buckled form of fully ionized DNA. On this basis, we derive a nonadditive relationship between the persistence length P of DNA and the persistence length P* of its null isomer. From the formula obtained we can predict the value of P* if P is known, and we can predict the ionic strength dependence of P under the assumption that P* does not depend on ionic strength. We predict a value of P* for null DNA drastically lower than the value of P for DNA in its ordinary state of fully ionized phosphates. The predicted dependence of P on salt concentration is log-c over most of the concentration range, with no tendency toward a salt-independent value in the range of validity of the theory. The predictions are consistent with much of the persistence-length data available for DNA. Alternate theories of the Odijk-Skolnik-Fixman type, including one by the author, are considered skeptically on the grounds that the underlying model may not be realistic. Specifically, we doubt the accuracy for real polyelectrolytes of the Odijk-Skolnik-Fixman assumption that the polymer structure is invariant to changes in electrostatic forces.

Manning, Gerald S.

2006-01-01

117

The ``Phantom'' Force1  

Microsoft Academic Search

IT might be supposed that permanent and entirely local or ``internal'' force-pairs of this kind acting on innumerable material couplets in a system would so disturb the individual energies of their motions that no general conclusion as to the total change of energy during the progress of such a system's motion could be drawn; but the simple law that impulses

A. S. Herschel

1878-01-01

118

Family Support in the German Armed Forces.  

National Technical Information Service (NTIS)

In recent history, German armed forces have been transformed into a modern, international recognized force. Readiness suddenly was a major issue and personal disposition was a core value of a soldier's profession. Soldiers suddenly had to be prepared for ...

G. Kreim

2006-01-01

119

Force cycles and force chains.  

PubMed

We examine the coevolution of N cycles and force chains as part of a broader study which is designed to quantitatively characterize the role of the laterally supporting contact network to the evolution of force chains. Here, we elucidate the rheological function of these coexisting structures, especially in the lead up to failure. In analogy to force chains, we introduce the concept of force cycles: N cycles whose contacts each bear above average force. We examine their evolution around force chains in a discrete element simulation of a dense granular material under quasistatic biaxial loading. Three-force cycles are shown to be stabilizing structures that inhibit relative particle rotations and provide strong lateral support to force chains. These exhibit distinct behavior from other cycles. Their population decreases rapidly during the initial stages of the strain-hardening regime-a trend that is suddenly interrupted and reversed upon commencement of force chain buckling prior to peak shear stress. Results suggest that the three-force cycles are called upon for reinforcements to ward off failure via shear banding. Ultimately though, the resistance to buckling proves futile; buckling wins under the combined effects of dilatation and increasing compressive load. The sudden increase in three-force cycles may thus be viewed as an indicator of imminent failure via shear bands. PMID:20365363

Tordesillas, Antoinette; Walker, David M; Lin, Qun

2010-01-13

120

Dextrous hand grasping force optimization  

Microsoft Academic Search

A key goal in dextrous robotic hand grasping is to balance external forces and at the same time achieve grasp stability and minimum grasping energy by choosing an appropriate set of internal grasping forces. Since it appears that there is no direct algebraic optimization approach, a recursive optimization, which is adaptive for application in a dynamic environment, is required. One

Martin BUSS; Hideki Hashimoto; John B. Moore

1996-01-01

121

One Force  

NASA Astrophysics Data System (ADS)

There is only one entity that can extend force and couple through space; and it should be apparent that Electromagnetism is that entity. In the cases of the nuclear strong force and the nuclear weak force, this is the same fundamental Electromagnetism manifesting itself in two different ways in the nucleus. It remains the same basic Electromagnetism. On the other hand, General Relativity fails to produce force at a distance, fails the Cavendish experiment, and does not allow an apple to fall to the ground. The result shows there is only Electromagnetism that functions through physical nature providing gravity, actions in the nucleus, as well as all other physical actions universally, including Gravity and Gravitation. There are many direct proofs of this, the same proofs as in NUCLEAR QUANTUM GRAVITATION. In contrast, General Relativity plainly relies on fallacy abstract and incoherent proofs; proofs which have now been mostly disproved. In the past it was deemed necessary by some to have an "ether" to propagate Electromagnetic waves. The fallacy concept of time space needs "space distortions" in order to cause gravity. However, Electromagnetic gravity does not have this problem. Clearly there is only ONE FORCE that causes Gravity, Electromagnetism, the Nuclear Strong Force, and the Nuclear Weak Force, and that ONE FORCE is Electromagnetism.

Kotas, Ronald R.

2002-04-01

122

Dam Forces  

NSDL National Science Digital Library

Students learn how the force of water helps determine the size and shape of dams. They use clay to build models of four types of dams, and observe the force of the water against each type. They conclude by deciding which type of dam they, as Splash Engineering engineers, will design for Thirsty County.

Integrated Teaching And Learning Program And Laboratory

123

Forces and motion  

NSDL National Science Digital Library

In this activity, students will understand the following (1) gravity is the force of attraction that causes objects to fall toward the center of the earth, (2) air resistance, or air friction, can slow down the acceleration of a falling object, (3) the area 'fronting the wind' affects the amount of air resistance a falling object encounters, (4) terminal speed is the speed at which the downward pull of gravity is balanced by the equal and upward opposing force of air resistance for a falling object. This would be a suitable activity for small groups. Copyright 2005 International Technology Education Association

Latham, Ted

2002-01-01

124

Force sensor  

DOEpatents

A force sensor and related method for determining force components. The force sensor includes a deformable medium having a contact surface against which a force can be applied, a signal generator for generating signals that travel through the deformable medium to the contact surface, a signal receptor for receiving the signal reflected from the contact surface, a generation controller, a reception controller, and a force determination apparatus. The signal generator has one or more signal generation regions for generating the signals. The generation controller selects and activates the signal generation regions. The signal receptor has one or more signal reception regions for receiving signals and for generating detections signals in response thereto. The reception controller selects signal reception regions and detects the detection signals. The force determination apparatus measures signal transit time by timing activation and detection and, optionally, determines force components for selected cross-field intersections. The timer which times by activation and detection can be any means for measuring signal transit time. A cross-field intersection is defined by the overlap of a signal generation region and a signal reception region.

Grahn, Allen R. (Salt Lake City, UT)

1993-01-01

125

EULAR recommendations for the management of knee osteoarthritis: report of a task force of the Standing Committee for International Clinical Studies Including Therapeutic Trials (ESCISIT)  

PubMed Central

BACKGROUND—Osteoarthritis (OA) is the most common joint disease encountered throughout Europe. A task force for the EULAR Standing Committee for Clinical Trials met in 1998 to determine the methodological and logistical approach required for the development of evidence based guidelines for treatment of knee OA. The guidelines were restricted to cover all currently available treatments for knee OA diagnosed either clinically and/or radiographically affecting any compartment of the knee.?METHODS—The first stage was the selection of treatment modalities to be considered. The second stage comprised a search of the electronic databases Medline and Embase using a combination of subject headings and keywords. All European language publications in the form of systematic reviews, meta-analyses, randomised controlled trials, controlled trials, and observational studies were included. During stage three all the relevant studies were quality scored. The summary statistics for validated outcome measures, when available, were recorded and, where practical, the numbers needed to treat and the effect size for each treatment were calculated. In the fourth stage key clinical propositions were determined by expert consensus employing a Delphi approach. The final stage ranked these propositions according to the available evidence. A second set of propositions relating to a future research agenda was determined by expert consensus using a Delphi approach.?RESULTS—Over 2400 English language publications and 400 non-English language publications were identified. Seven hundred and forty four studies presented outcome data of the effects of specific treatments on knee OA. Quantitative analysis of treatment effect was possible in only 61 studies. Recommendations for the management of knee OA based on currently available data and expert opinion are presented. Proposals for a future research agenda are highlighted.?CONCLUSIONS—These are the first clinical guidelines on knee OA to combine an evidence based approach and a consensus approach across a wide range of treatment modalities. It is apparent that certain clinical propositions are supported by substantial research based evidence, while others are not. There is thus an urgent need for future well designed trials to consider key clinical questions.??

Pendleton, A; Arden, N; Dougados, M; Doherty, M; Bannwarth, B; Bijlsma, J; Cluzeau, F; Cooper, C; Dieppe, P; Gunther, K; Hauselmann, H; Herrero-Beaumont, G; Kaklamanis, P; Leeb, B; Lequesne, M; Lohmander, S; Mazieres, B; Mola, E; Pavelka, K; Serni, U; Swoboda, B; Verbruggen, A; Weseloh, G; Zimmermann-Gorska, I

2000-01-01

126

Centripetal Force  

NSDL National Science Digital Library

In this animation a ball bounces off the sides of the circle, and the number of sides double, until the circle appears to exert force on a ball that is constant in size and always directed towards the center.

Wpsu

2010-04-09

127

Force distribution analysis of mechanochemically reactive dimethylcyclobutene.  

PubMed

Internal molecular forces can guide chemical reactions, yet are not straightforwardly accessible within a quantum mechanical description of the reacting molecules. Here, we present a force-matching force distribution analysis (FM-FDA) to analyze internal forces in molecules. We simulated the ring opening of trans-3,4-dimethylcyclobutene (tDCB) with on-the-fly semiempirical molecular dynamics. The self-consistent density functional tight binding (SCC-DFTB) method accurately described the force-dependent ring-opening kinetics of tDCB, showing quantitative agreement with both experimental and computational data at higher levels. Mechanical force was applied in two different ways, namely, externally by a constant pulling force and internally by embedding tDCB within a strained macrocycle-containing stiff stilbene. We analyzed the distribution of tDCB internal forces in the two different cases by FM-FDA and found that external force gave rise to a symmetric force distribution in the cyclobutene ring, which also scaled linearly with the external force, indicating that the force distribution was uniquely determined by the symmetric architecture of tDCB. In contrast, internal forces due to stiff stilbene resulted in an asymmetric force distribution within tDCB, which indicated a different geometry of force application and supported the important role of linkers in the mechanochemical reactivity of tDCB. In addition, three coordinates were identified through which the distributed forces contributed most to rate acceleration. These coordinates are mostly parallel to the coordinate connecting the two CH3 termini of tDCB. Our results confirm previous observations that the linker outside of the reactive moiety, such as a stretched polymer or a macrocycle, affects its mechanochemical reactivity. We expect FM-FDA to be of wide use to understand and quantitatively predict mechanochemical reactivity, including the challenging cases of systems within strained macrocycles. PMID:23843171

Li, Wenjin; Edwards, Scott A; Lu, Lanyuan; Kubar, Tomas; Patil, Sandeep P; Grubmüller, Helmut; Groenhof, Gerrit; Gräter, Frauke

2013-07-10

128

Physlet Force Concept Inventory: Forces  

NSDL National Science Digital Library

A large truck breaks down out on the road and receives a push back into town by a small compact car as shown in the animation. Learners are to answer questions regarding forces exerted by the two vehicles.

Christian, Wolfgang; Belloni, Mario

2006-01-13

129

International Responses to Territorial Conquest  

Microsoft Academic Search

The prohibition on territorial conquest is a cornerstone of the international legal order. The United Nations Charter bans the use of force as a tool of international relations, even when used to rectify prior injustices. Thus territory taken by force has the status of ill-gotten gains, and cannot be kept by the victor. An important corollary is that third-party states

Eugene Kontorovich

2009-01-01

130

Neurology and international organizations.  

PubMed

A growing number of international stakeholders are engaged with neurologic diseases. This article provides a brief overview of important international stakeholders in the practice of neurology, including global disease-specific programs, United Nations agencies, governmental agencies with international influence, nongovernmental organizations, international professional organizations, large private donors, private-public partnerships, commercial interests, armed forces, and universities and colleges. The continued engagement of neurologists is essential for the growing number of international organizations that can and should incorporate neurologic disease into their global agendas. PMID:23877795

Mateen, Farrah J

2013-07-23

131

Adomian series solution for computing the effect of size dependency of material characteristics on the internal stress field of cantilever nano-actuators in the presence of intermolecular force  

NASA Astrophysics Data System (ADS)

In this paper the effect of size dependency and Van der Waals intermolecular force on force distribution of electrostatic cantilever nano-actuators at nano-scale separations have been studied using Adomian decomposition method. An analytical closed-form solution has been obtained. Shear force along the cantilevers are computed and compared with numerical solution.

Vahdati, Alireza; Khani, Ahmad; Jandaghian, Masoud; Alimoradi, Fakhrodin

2012-09-01

132

Air Force seal activities  

NASA Astrophysics Data System (ADS)

Seal technology development is an important part of the Air Force's participation in the Integrated High Performance Turbine Engine Technology (IHPTET) initiative, the joint DOD, NASA, ARPA, and industry endeavor to double turbine engine capabilities by the turn of the century. Significant performance and efficiency improvements can be obtained through reducing internal flow system leakage, but seal environment requirements continue to become more extreme as the engine thermodynamic cycles advance towards these IHPTET goals. Brush seal technology continues to be pursued by the Air Force to reduce leakage at the required conditions. Likewise, challenges in engine mainshaft air/oil seals are also being addressed. Counter-rotating intershaft applications within the IHPTET initiative involve very high rubbing velocities. This viewgraph presentation briefly describes past and current seal research and development programs and gives a summary of seal applications in demonstrator and developmental engine testing.

Mayhew, Ellen R.

1994-07-01

133

Nonequilibrium quantum fluctuation forces  

NASA Astrophysics Data System (ADS)

We study all known and as yet unknown forces between neutral atoms and neutral atoms and surfaces. The forces arise from mutual influences mediated by an attending electromagnetic field and not from direct interaction. We allow as dynamical variables the center of mass motion of the atom (or surface Chapter 5), its internal degrees of freedom, modeled as a three dimensional harmonic oscillator (the internal degrees of freedom of the surface in chapter 4), and the quantum field treated relativistically. We adopt the methods of nonequilibrium quantum field theory (NEqQFT) to study the problem of fluctuation forces beginning from first principles. NEqQFT provides a fully dynamical description of systems far from equilibrium having the advantage of being the synthesis of quantum field theory and nonequilibrium statistical mechanics. The integration of these two paradigms is necessary for a complete study of fluctuation forces; quantum field theory for providing effects such as retardation and quantum field fluctuations, and nonequilbrium statistical mechanics for treating processes involving quantum dissipation and noises. By embarking from first principles we avoid wrong or only partially correct results from inconsistent theories that can be generated from assumptions made at lower levels of accuracy. In thermodynamic equilibrium we reproduce all the effects and forces known in the last century, such as Casimir-Polder---between neutral atoms, Lifshitz---between an atom and a surface and Casimir between surfaces (and the generalization of these forces to nonequilibrium stationary-states). More noteworthy is the discovery of the existence of a new type of interatomic force which we call the 'entanglement force', originating from the quantum correlations of the internal degrees of freedom of entangled atoms. Fluctuation phenomena associated with quantum fields is a new frontier of future research in atom-field interaction. With NEqQFT we have derived Langevin equations which account for fluctuations of an atom's trajectory about its semi-classical value. These quantum field-induced perturbations of the atom's position could lead to measurable results such as the damping of the center-of-mass oscillations of a trapped Bose-Einstein condensate near a surface or backaction cooling of moving mirror by radiative pressure and quantum viscosity discussed respectively in Chapter 3 and 5 of this thesis. The methods introduced in this thesis for treating atom-field interactions or mirror-field interactions go beyond previous work by providing a fully dynamical description of these forces valid for arbitrary atom and surface motion, indeed the inclusion of self-consistent backactions are necessary for the study of phenomena such as quantum decoherence and entanglement dynamics, including non-Markovian processes which invariably will appear when backaction is taken into consideration (especially for strong fields, low temperatures, or fast response).

Behunin, Ryan Orson

134

Can a small-changes approach help address the obesity epidemic? A report of the Joint Task Force of the American Society for Nutrition, Institute of Food Technologists, and International Food Information Council.  

PubMed

The continued rise in obesity rates in most countries suggests that current programs and initiatives designed to combat obesity have not been successful in reversing the obesity epidemic. Obesity rates are increasing because of a gradual weight gain in most populations. There has been little long-term success in treating established obesity through lifestyle change, perhaps because of the large permanent changes in diet and physical activity required to keep weight off. An alternative strategy to address the obesity epidemic involves not focusing on weight loss but promoting small changes in diet and physical activity to initially prevent further weight gain. With the use of this strategy, obesity rates could first be stabilized in most populations and then, over time, decrease gradually. Supporting data show that small reductions in conscious energy intake and increases in physical activity can reduce excessive weight gain. The opportunity exists to use the small-changes approach to bring different stakeholders together to create a national initiative to address the global epidemic of obesity. The Joint Task Force of the American Society for Nutrition, Institute of Food Technologists, and International Food Information Council believe that a small-changes framework, aimed at helping people make conscious small changes in lifestyle behaviors, in combination with efforts by the private sector to gradually "ratchet down" some of the environmental factors that have contributed to excessive energy intake and the declining rates of physical activity, can be successful in reducing obesity rates. Such an initiative would benefit from the support of educational and social marketing campaigns developed with governmental input and support. PMID:19088151

Hill, James O

2008-12-16

135

Integrated Global Force Postures: An Overview.  

National Technical Information Service (NTIS)

The report describes the approach to the problem of deriving guidelines global force posture planning for the 1980s. It discusses the necessity to consider the implications for national security of changes in the international environment. Among such chan...

S. P. Gibert W. M. Carpenter

1973-01-01

136

Correlation of axial impact forces with knee joint forces and kinematics during simulated ski-landing.  

PubMed

Anterior cruciate ligament (ACL) rupture, during ski-landing, is caused by excessive knee joint forces and kinematics, like anterior tibial translation, internal tibial rotation, and valgus rotation. It is not well understood how these forces/kinematics are directly related to ski-landing impact. In the present study, we applied simulated ski-landing impact to knee specimens, and examined joint force/kinematic responses and their correlations with impact force. Ten human cadaveric knees were subjected to axial impact loading at 70° of flexion to simulate ski-landing impact. Impact was repeated with incremental magnitude until ACL failure. Axial impact forces, anterior-posterior and medial-lateral tibial forces were measured using a tri-axial load cell. Anterior-posterior tibial translation, internal-external tibial rotation, and valgus-varus rotation were determined using a motion-capture system. We found positive correlations of axial impact force with anterior tibial force, medial tibial force, anterior tibial translation, internal tibial rotation, and valgus joint rotation. Axial impact forces were more strongly correlated with anterior tibial forces (R(2) = 0.937 ± 0.050), anterior tibial translation (R(2) = 0.916 ± 0.059), and internal tibial rotation (R(2) = 0.831 ± 0.141) than medial tibial force (R(2) = 0.677 ± 0.193) and valgus joint rotation (R(2) = 0.630+0.271). During ski-landing, these joint forces/kinematics can synergistically act to increase ACL injury risk, whereby the failure mechanism would be dominated by anterior tibial forces, anterior tibial translation, and internal tibial rotation. PMID:21774750

Yeow, Chen-Hua; Kong, Chin-Yang; Lee, Peter Vee-Sin; Goh, James Cho-Hong

2011-07-21

137

Measuring colloidal forces using evanescent wave scattering  

Microsoft Academic Search

The evanescent wave scattering technique total internal reflection microscopy has enabled the direct measurement of the mean potential energy of interaction between a Brownian particle and a flat surface. With a distance resolution of 1 nm and a force resolution of 10 fN, this technique has successfully measured a variety of colloidal forces. Recent measurements of van der Waals interactions

Stacy G Bike

2000-01-01

138

Quality Air Force and Deming's Fourteen Points.  

National Technical Information Service (NTIS)

As a result of the changing international and domestic environments the United States Air Force is in the midst of the most significant change since the end of the World War II. This enormous effort is being led by the Air Force senior leadership with a g...

T. M. Kocon

1994-01-01

139

The future of general internal medicine  

Microsoft Academic Search

The Society of General Internal Medicine asked a task force to redefine the domain of general internal medicine. The task\\u000a force believes that the chaos and dysfunction that characterize today’s medical care, and the challenges facing general internal\\u000a medicine, should spur innovation. These are our recommendations: while remaining true to its core values and competencies,\\u000a general internal medicine should stay

Eric B. Larson; Stephan D. Fihn; Lynne M. Kirk; Wendy Levinson; Ronald V. Loge; Eileen Reynolds; Lewis Sandy; Steven Schroeder; Neil Wenger; Mark Williams

2004-01-01

140

Knee joint forces: prediction, measurement, and significance  

PubMed Central

Knee forces are highly significant in osteoarthritis and in the survival and function of knee arthroplasty. A large number of studies have attempted to estimate forces around the knee during various activities. Several approaches have been used to relate knee kinematics and external forces to internal joint contact forces, the most popular being inverse dynamics, forward dynamics, and static body analyses. Knee forces have also been measured in vivo after knee arthroplasty, which serves as valuable validation of computational predictions. This review summarizes the results of published studies that measured knee forces for various activities. The efficacy of various methods to alter knee force distribution, such as gait modification, orthotics, walking aids, and custom treadmills are analyzed. Current gaps in our knowledge are identified and directions for future research in this area are outlined.

D'Lima, Darryl D.; Fregly, Benjamin J.; Patil, Shantanu; Steklov, Nikolai; Colwell, Clifford W.

2011-01-01

141

Internal auditing education : a comparison across countries  

Microsoft Academic Search

Society?s recognition of the importance of internal auditing has increased in recent years. This has resulted in an increased recognition of the need for improving and formalizing the manner in which internal auditors are educated. Suggests some of the forces that have led to this increased awareness of the value of internal auditing and discusses historical changes in internal auditing

Sheila D. Foster; Mary Brady Greenawalt

1995-01-01

142

Mandibular distraction force: Laboratory data and clinical correlation  

Microsoft Academic Search

Purpose: In vitro data were collected to measure torque-force values of an internal distraction device. The measurements were correlated with in vivo torque readings in an attempt to better understand the force required to distract the osteogenic bone callus of the human mandible during distraction osteogenesis. Methods and Materials: Five internal craniofacial distraction devices were mounted on an apparatus to

Randolph C. Robinson; Patrick J. O'Neal; Ginger H. Robinson

2001-01-01

143

Correlation of axial impact forces with knee joint forces and kinematics during simulated ski-landing  

Microsoft Academic Search

Anterior cruciate ligament (ACL) rupture, during ski-landing, is caused by excessive knee joint forces and kinematics, like anterior tibial translation, internal tibial rotation, and valgus rotation. It is not well understood how these forces\\/kinematics are directly related to ski-landing impact. In the present study, we applied simulated ski-landing impact to knee specimens, and examined joint force\\/kinematic responses and their correlations

Chen Hua Yeow; Chin Yang Kong; Peter Vee-Sin Lee; James Cho-Hong Goh

2011-01-01

144

Manipulating and grasping forces in manipulation by multifingered robot hands  

Microsoft Academic Search

A new definition of grasping and manipulating forces for multifingered robot hands is proposed. First, a short discussion of the grasping and manipulating forces for two-fingered hands with linear motion is given to explain the motivation more clearly and to give the basic idea of the new definition. Then, for three-fingered hands, based on a representation of the internal force,

Tsuneo Yoshikawa; Kiyoshi Nagai

1991-01-01

145

Ramp: Forces and Motion  

NSDL National Science Digital Library

Explore forces and motion as you push household objects up and down a ramp. Lower and raise the ramp to see how the angle of inclination affects the parallel forces. Graphs show forces, energy and work.

Simulations, Phet I.; Reid, Sam; Podolefsky, Noah; Loeblein, Trish; Perkins, Kathy

2010-10-01

146

Air Force brush seal programs  

NASA Astrophysics Data System (ADS)

Aggressive pursuit of increased performance in gas turbine engines is driving the thermodynamic cycle to higher pressure ratios, bypass ratios, and turbine inlet temperatures. As these parameters increase, internal air system and resultant thermodynamic cycle losses increase. This conflict of reducing internal airflows while increasing thermodynamic efficiency and performance is putting more emphasis on improvements to the internal flow system. One improvement that has been and continues to be pursued by the Air Force for both man-rated and expendable turbine engine applications is the brush seal. This presentation briefly describes both past and current brush seal research and development programs and gives a summary of demonstrator and developmental engine testing of brush seals.

Dowler, Connie

1993-10-01

147

Cell Adhesion Force Microscopy  

Microsoft Academic Search

The adhesion forces of cervical carcinoma cells in tissue culture were measured by using the manipulation force microscope, a novel atomic force microscope. The forces were studied as a function of time and temperature for cells cultured on hydrophilic and hydrophobic polystyrene substrates with preadsorbed proteins. The cells attached faster and stronger at 37 degrees C than at 23 degrees

G. Sagvolden; I. Giaever; E. O. Pettersen; J. Feder

1999-01-01

148

Force and Momentum  

Microsoft Academic Search

IT is commonly said that change of momentum is evidence that force has acted or is acting on the mass, and that the rate at which the momentum is changing is the measure of the force. Thus, in his lecture on ``Force'', Prof. Tait says: ``Force is the rate of change of momentum'' (NATURE, vol. xiv. p. 462). This is

E. G

1879-01-01

149

Protection considerations for force-cooled superconductors  

SciTech Connect

This paper treats some hydrodynamic aspects of protecting magnets wound with force-cooled superconductors, namely, the rise in internal pressure and the forceful expulsion of helium during a quench. Two initial conditions are considered: an entire hydraulic path going normal all at once, and an initially small but nonrecovering normal zone. Formulas are given for the quench pressure and expulsion velocity in both cases and are compared with available experimental data.

Dresner, L.

1985-01-01

150

Intermolecular Forces (Netorials)  

NSDL National Science Digital Library

Intermolecular Forces: this is a resource in the collection "Netorials". In this resource there is a review of Lewis structures, molecular geometry, electronegativity, or molecular polarity. After that, you can learn about the forces of attraction that exist between molecules. This module explores London forces and dipole-dipole forces (including hydrogen bonds). The Netorials cover selected topics in first-year chemistry including: Chemical Reactions, Stoichiometry, Thermodynamics, Intermolecular Forces, Acids & Bases, Biomolecules, and Electrochemistry.

151

INTERNAL CUTTING DEVICE  

DOEpatents

A device is described for removing material from the interior of a hollow workpiece so as to form a true spherical internal surface in a workpiece, or to cut radial slots of an adjustable constant depth in an already established spherical internal surface. This is accomplished by a spring loaded cutting tool adapted to move axially wherein the entire force urging the tool against the workpiece is derived from the spring. Further features of importance involve the provision of a seal between the workpiece and the cutting device and a suction device for carrying away particles of removed material.

Russell, W.H. Jr.

1959-06-30

152

International market segmentation: issues and perspectives  

Microsoft Academic Search

With the increasing globalization of the business world, international segmentation becomes an ever more important concept in marketing. The globalization forces now at work push many companies to extend or reorganize their marketing strategies across borders and target international segments of consumers. It is the purpose of this paper to review the international market segmentation literature and to identify its

Jan-Benedict E. M Steenkamp; Frenkel Ter Hofstede

2002-01-01

153

Weapons of Mass Destruction & Public International Law  

Microsoft Academic Search

The proliferation of weapons of mass destruction (WMD) into the hands of rogue dictators and terrorists has brought a sea change in strategic international relations, and is accelerating the necessity of public international law to protect humanity. Traditional balances of power have little force left to deter WMD. Major powers must seriously revamp and proactively exploit public international law, and,

Michael Donlan

2005-01-01

154

Ventromedial Prefrontal Cortex Lesions and Motivational Internalism  

Microsoft Academic Search

This article discusses the argument by Roskies to the effect that ventromedial prefrontal cortex (VMPFC) patients are a living counterexample to motivational internalism. Motivational internalism is a philosophical position according to which moral judgments are accompanied by a particular motivational force that induces agents to act accordingly. Roskies takes into account a very strong version of motivational internalism and claims

Tommaso Bruni

2012-01-01

155

Internal-tide generation and destruction by shoaling internal tides  

NASA Astrophysics Data System (ADS)

Internal-tide generation is usually predicted from local topography, surface tides, and stratification. However, internal tides are often observed to be unrelated to local spring-neap forcing, appearing intermittently in 3-5 day bursts. Here we suggest a source of this intermittency by illustrating how remotely-generated shoaling internal tides induce first-order changes in local internal-tide generation. Theory, numerical simulations, and observations show that pressure perturbations associated with shoaling internal tides can correlate with surface-tide velocities to generate or destroy internal tides. Where shoaling internal tides have random phase, such as on the New Jersey slope, time-averaged internal-tide generation is unaffected, but instantaneous internal-tide generation varies rapidly, altering internal-tide energy and possibly affecting nonlinear internal waves, across-shelf transport, and mixing. Where shoaling internal tides are phase-locked to the local surface tide, such as in double-ridge systems, time-averaged internal-tide generation is affected and may result in resonance.

Kelly, S. M.; Nash, J. D.

2010-12-01

156

A molecular force probe  

NASA Astrophysics Data System (ADS)

Force probes allow reaction rates to be measured as a function of the restoring force in a molecule that has been stretched or compressed. Unlike strain energy, approaches based on restoring force allow quantitative molecular understanding of phenomena as diverse as translation of microscopic objects by reacting molecules, crack propagation and mechanosensing. Conceptually, localized reactions offer the best opportunity to gain fundamental insights into how rates vary with restoring forces, but such reactions are particularly difficult to study systematically using microscopic force probes. Here, we show how a molecular force probe, stiff stilbene, simplifies force spectroscopy of localized reactions. We illustrate the capabilities of our approach by validating the central postulate of chemomechanical kinetics-force lowers the activation barrier proportionally to the difference in a single internuclear distance between the ground and transition states projected on the force vector-on a paradigmatic unimolecular reaction: concerted dissociation of the C-C bond.

Yang, Qing-Zheng; Huang, Zhen; Kucharski, Timothy J.; Khvostichenko, Daria; Chen, Joseph; Boulatov, Roman

2009-05-01

157

On The 5D Extra-Force according to Basini-Capozziello-Ponce De Leon Formalism and the Experimental Research of Extra Dimensions On-Board International Space Station(ISS) using Laser Beams  

Microsoft Academic Search

We analyze the possibility of Experimental Research of Extra Dimensions On-Board International Space Station (ISS) by using a Satellite carrying a Laser device(optical Laser) on the other side of Earth Orbit targeted towards ISS.The Sun will be between the Satellite and the ISS so the Laser will pass the neighborhoods of the Sun at a distance $R$ in order to

Fernando Loup

2007-01-01

158

Contact sensing from force measurements  

SciTech Connect

This article addresses contact sensing (i.e., the problem of resolving the location of a contact, the force at the interface, and the moment about the contact normals). Called `intrinsic` contact sensing for the use of internal force and torque measurements, this method allows for practical devices that provide simple, relevant contact information in practical robotic applications. Such sensors have been used in conjunction with robot hands to identify objects, determine surface friction, detect slip, augment grasp stability, measure object mass, probe surfaces, and control collision and for a variety of other useful tasks. This article describes the theoretical basis for their operation and provides a framework for future device design. 24 refs., 12 figs., 3 tabs.

Bicchi, A.; Salisbury, J.K.; Brock, D.L. [Massachusetts Inst. of Technology, Cambridge (United States)

1993-06-01

159

Forces in general relativity  

NASA Astrophysics Data System (ADS)

Many textbooks dealing with general relativity do not demonstrate the derivation of forces in enough detail. The analyses presented herein demonstrate straightforward methods for computing forces by way of general relativity. Covariant divergence of the stress-energy-momentum tensor is used to derive a general expression of the force experienced by an observer in general coordinates. The general force is then applied to the local co-moving coordinate system of a uniformly accelerating observer, leading to an expression of the inertial force experienced by the observer. Next, applying the general force in Schwarzschild coordinates is shown to lead to familiar expressions of the gravitational force. As a more complex demonstration, the general force is applied to an observer in Boyer-Lindquist coordinates near a rotating, Kerr black hole. It is then shown that when the angular momentum of the black hole goes to zero, the force on the observer reduces to the force on an observer held stationary in Schwarzschild coordinates. As a final consideration, the force on an observer moving in rotating coordinates is derived. Expressing the force in terms of Christoffel symbols in rotating coordinates leads to familiar expressions of the centrifugal and Coriolis forces on the observer. It is envisioned that the techniques presented herein will be most useful to graduate level students, as well as those undergraduate students having experience with general relativity and tensor analysis.

Ridgely, Charles T.

2010-07-01

160

Forces in the Atmosphere  

NSDL National Science Digital Library

This undergraduate meteorology tutorial is about understanding the forces that cause the motion of air, producing winds and changes of weather. It discusses how these forces tend to balance each other, and how they produce the wind.

Nielsen-Gammon, John

1996-01-01

161

Methamphetamine Interagency Task Force.  

National Technical Information Service (NTIS)

The Methamphetamine Interagency Task Force was established in 1996 in response to a provision of the Comprehensive Methamphetamine Control Act. This report represents the 2-year effort of the Task Force presenting: the principles that have guided the Task...

2000-01-01

162

Forces and Motion: Basics  

NSDL National Science Digital Library

Explore the forces at work in a tug of war or pushing a refrigerator, crate, or person. Create an applied force and see how it makes objects move. Change friction and see how it affects the motion of objects.

Simulations, Phet I.; Podolefsky, Noah; Reid, Sam; Paul, Ariel; Perkins, Kathy; Loeblein, Trish

2012-10-24

163

Dietary Supplements Task Force.  

National Technical Information Service (NTIS)

The Dietary Supplements Task Force was charged with examining the issues regarding dietary supplements and developing a regulatory framework for these products. To facilitate the orderly development of regulatory strategies, the Task Force divided the uni...

1992-01-01

164

Aerodynamic Lifting Force.  

ERIC Educational Resources Information Center

|Describes some experiments showing both qualitatively and quantitatively that aerodynamic lift is a reaction force. Demonstrates reaction forces caused by the acceleration of an airstream and the deflection of an airstream. Provides pictures of demonstration apparatus and mathematical expressions. (YP)|

Weltner, Klaus

1990-01-01

165

Forces in One Dimension  

NSDL National Science Digital Library

The representation depicts the relationship between frictional and applied forces for a variety of objects in an interactive simulation. As the user manipulates objects, charts show the resulting forces and depict position, velocity, and acceleration vs. time.

166

Citizen groups: a creative force  

SciTech Connect

The role of citizen groups is as important as that of government agencies when it comes to environmental policy in a democracy. These groups spend little money, yet they have initiated the major US environmental legislation of the past two decades. They are a recent, but effective, force in developing countries even though adversarial approaches are not often appropriate. The methods used by US environmental groups range from lobbying to confrontation in court. Groups outside the US tend to use consensus in democracies and information gathering in developing countries. While the groups' primary concerns are national in scope, international awareness and cooperation are growing. (DCK)

Stoel, T.

1981-02-01

167

Fluid force transducer  

DOEpatents

An electrical fluid force transducer for measuring the magnitude and direction of fluid forces caused by lateral fluid flow, includes a movable sleeve which is deflectable in response to the movement of fluid, and a rod fixed to the sleeve to translate forces applied to the sleeve to strain gauges attached to the rod, the strain gauges being connected in a bridge circuit arrangement enabling generation of a signal output indicative of the magnitude and direction of the force applied to the sleeve.

Jendrzejczyk, Joseph A. (Warrenville, IL)

1982-01-01

168

Subpiconewton Intermolecular Force Microscopy  

Microsoft Academic Search

We refined scanning probe force microscopy to improve the sensitivity of force detection and control of probe position. Force sensitivity was increased by incorporating a cantilever with very low stiffness, 0.1pN\\/nm, which is over 1000-fold more flexible than is typically used in conventional atomic force microscopy. Thermal bending motions of the cantilever were reduced to less than 1 nm by

Makio Tokunaga; Takaaki Aoki; Michio Hiroshima; Kazuo Kitamura; Toshio Yanagida

1997-01-01

169

Forces in General Relativity  

ERIC Educational Resources Information Center

|Many textbooks dealing with general relativity do not demonstrate the derivation of forces in enough detail. The analyses presented herein demonstrate straightforward methods for computing forces by way of general relativity. Covariant divergence of the stress-energy-momentum tensor is used to derive a general expression of the force experienced…

Ridgely, Charles T.

2010-01-01

170

Crossflow force transducer. [LMFBR  

SciTech Connect

A force transducer for measuring lift and drag coefficients for a circular cylinder in turbulent water flow is presented. In addition to describing the actual design and construction of the strain-gauged force- ring based transducer, requirements for obtained valid fluid force test data are discussed, and pertinent flow test experience is related.

Mulcahy, T.M.

1982-05-01

171

Strategic forces briefing  

Microsoft Academic Search

The Strategic Forces Briefing'' is our attempt, accomplished over the past several months, to outline and highlight the more significant strategic force issues that must be addressed in the near future. Some issues are recurrent: the need for an effective modernized Triad and a constant concern for force survivability. Some issues derive from arms control: the Strategic Arms Reduction Talks

G. Bing; P. Chrzanowski; M. May; M. Nordyke

1989-01-01

172

International guidelines for management of metastatic breast cancer (MBC) from the European School of Oncology (ESO)-MBC Task Force: Surveillance, staging, and evaluation of patients with early-stage and metastatic breast cancer.  

PubMed

In clinical practice, the surveillance and follow-up of patients with breast cancer (BC) is quite variable. At the 7th European Breast Cancer Conference, the ESO-MBC Task Force convened a series of lectures, followed by open debate, on the use of physical examination, imaging, and laboratory tests in patients with early-stage BC, and for restaging evaluations and follow-up among patients with MBC. Based on the available data, the Task Force recommends against intensive, routine radiologic or blood-based surveillance (with the exception of mammography) in patients with early-stage BC. As systemic therapies for MBC continue to improve, this question might be re-visited in the context of a carefully controlled clinical trial in specific BC subtypes. For patients with MBC, response to therapy should generally be assessed 2-3 months after initiation of treatment, and thereafter every 2-4 months for endocrine therapy or every 2-4 cycles for chemotherapy, depending on the dynamics of the disease, the location and extent of metastatic involvement, and type of treatment. Additional testing should be performed irrespective of the planned intervals if progression of disease is suspected (e.g. in the case of specific symptoms). Use of tumor markers is not recommended for surveillance of early-stage patients, but may be helpful in monitoring response to therapy in patients with metastatic disease. However, change in tumor markers alone should not be used for decision-making. Moving forward, enhanced efforts to document quality of life over time should be made in order to more fully evaluate the risk/benefit ratio of available options. PMID:23601761

Lin, Nancy U; Thomssen, Christoph; Cardoso, Fatima; Cameron, David; Cufer, Tanja; Fallowfield, Lesley; Francis, Prudence A; Kyriakides, Stella; Pagani, Olivia; Senkus, Elzbieta; Costa, Alberto; Winer, Eric P

2013-04-17

173

Force Concept Inventory: Forces and Speed  

NSDL National Science Digital Library

A rocket drifts sideways in outer space from point "a" to point "b" as shown in the animations. The rocket is subject to no outside forces. Starting at position "b", the rockets's engine is turned on and produces a constant thrust (force on the rocket) at right angles to the line "ab". The constant thrust is maintained until the rocket reaches a point "c" in space.

Christian, Wolfgang; Belloni, Mario

2006-01-13

174

Force Concept Inventory: Forces and Speed  

NSDL National Science Digital Library

A rocket drifts sideways in outer space from point "a" to point "b" as shown in the animations. The rocket is subject to no outside forces. Starting at position "b", the rockets's engine is turned on and produces a constant thrust (force on the rocket) at right angles to the line "ab". The constant thrust is maintained until the rocket reaches a point "c" in space. At point "c" the rocket's engine is turned off and the thrust immediately drops to zero.

Christian, Wolfgang; Belloni, Mario

2006-01-13

175

Multiple Forces in Component Localisation in China  

Microsoft Academic Search

Successful localisation of component sourcing is of key concern to the manufacturing subsidiaries of MNCs. However, a range of factors both internal and external to the firm can act as forces for or against successful component localisation. Based on a study of 27 UK-invested MNC subsidiaries in China — the world’s most important emerging market — this paper explores the

Markus Eberhardt; Julie McLaren; Andrew Millington; Barry Wilkinson

2004-01-01

176

Towards force standardisation for signature capture devices  

Microsoft Academic Search

A current focus within biometric technology research and development is the definition of international standards to enable interoperability of modality data collected on multiple devices and biometric processing engines. The human signature is a widely used form of biometric verification with widespread legal admissibility and acceptability for verification purposes. Within automatic signature verification systems the force of the pen exerted

Richard M. Guest

2009-01-01

177

Forcing mechanisms of the Indian Ocean monsoon  

Microsoft Academic Search

Sediments in the Arabian Sea provide biological, biogeochemical and lithogenic evidence of past changes in the Indian Ocean summer monsoon winds. For the past 350,000 years, this system has been externally forced by cyclical changes in solar radiation, and internally phase-locked to the transport of latent heat from the southern subtropical Indian Ocean to the Tibetan Plateau. In contrast to

Steven Clemens; Warren Prell; David Murray; Graham Shimmield; Graham Weedon

1991-01-01

178

U.S. Transport Task Force 2010  

SciTech Connect

The Transport Task Force (TTF) Meeting is a venue for vigorous scientific discourse and discussion on topics in transport and turbulence in fusion plasmas. Its participation is international. The 2010 meeting was highly effective, with 139 registered participants and 131 presentations. This is remarkable for an even year (IAEA year) meeting. The meeting clearly fostered progress in understanding and control of turbulent transport.

Diamond, P.H.

2011-09-21

179

Efficacy of climate forcings  

NASA Astrophysics Data System (ADS)

We use a global climate model to compare the effectiveness of many climate forcing agents for producing climate change. We find a substantial range in the "efficacy" of different forcings, where the efficacy is the global temperature response per unit forcing relative to the response to CO2 forcing. Anthropogenic CH4 has efficacy ˜110%, which increases to ˜145% when its indirect effects on stratospheric H2O and tropospheric O3 are included, yielding an effective climate forcing of ˜0.8 W/m2 for the period 1750-2000 and making CH4 the largest anthropogenic climate forcing other than CO2. Black carbon (BC) aerosols from biomass burning have a calculated efficacy ˜58%, while fossil fuel BC has an efficacy ˜78%. Accounting for forcing efficacies and for indirect effects via snow albedo and cloud changes, we find that fossil fuel soot, defined as BC + OC (organic carbon), has a net positive forcing while biomass burning BC + OC has a negative forcing. We show that replacement of the traditional instantaneous and adjusted forcings, Fi and Fa, with an easily computed alternative, Fs, yields a better predictor of climate change, i.e., its efficacies are closer to unity. Fs is inferred from flux and temperature changes in a fixed-ocean model run. There is remarkable congruence in the spatial distribution of climate change, normalized to the same forcing Fs, for most climate forcing agents, suggesting that the global forcing has more relevance to regional climate change than may have been anticipated. Increasing greenhouse gases intensify the Hadley circulation in our model, increasing rainfall in the Intertropical Convergence Zone (ITCZ), Eastern United States, and East Asia, while intensifying dry conditions in the subtropics including the Southwest United States, the Mediterranean region, the Middle East, and an expanding Sahel. These features survive in model simulations that use all estimated forcings for the period 1880-2000. Responses to localized forcings, such as land use change and heavy regional concentrations of BC aerosols, include more specific regional characteristics. We suggest that anthropogenic tropospheric O3 and the BC snow albedo effect contribute substantially to rapid warming and sea ice loss in the Arctic. As a complement to a priori forcings, such as Fi, Fa, and Fs, we tabulate the a posteriori effective forcing, Fe, which is the product of the forcing and its efficacy. Fe requires calculation of the climate response and introduces greater model dependence, but once it is calculated for a given amount of a forcing agent it provides a good prediction of the response to other forcing amounts.

Hansen, J.; Sato, M.; Ruedy, R.; Nazarenko, L.; Lacis, A.; Schmidt, G. A.; Russell, G.; Aleinov, I.; Bauer, M.; Bauer, S.; Bell, N.; Cairns, B.; Canuto, V.; Chandler, M.; Cheng, Y.; Del Genio, A.; Faluvegi, G.; Fleming, E.; Friend, A.; Hall, T.; Jackman, C.; Kelley, M.; Kiang, N.; Koch, D.; Lean, J.; Lerner, J.; Lo, K.; Menon, S.; Miller, R.; Minnis, P.; Novakov, T.; Oinas, V.; Perlwitz, Ja.; Perlwitz, Ju.; Rind, D.; Romanou, A.; Shindell, D.; Stone, P.; Sun, S.; Tausnev, N.; Thresher, D.; Wielicki, B.; Wong, T.; Yao, M.; Zhang, S.

2005-09-01

180

Faking It: Coriolis Force  

NSDL National Science Digital Library

This lesson will help students understand what the Coriolis force is, and what effects it has on objects in motion. Students will be able to describe and explain the Coriolis force, and compare and contrast conditions under which the Coriolis force has a significant impact on objects in motion with conditions under which the influence of the Coriolis force is negligible. Portions of this lesson are based on a webpage called "Bad Coriolis", a resource devoted to correcting misconceptions about the Coriolis force and other natural phenomena.

181

International Terrorism in South Asia  

Microsoft Academic Search

This report reviews the international terrorist environment in South Asia, concentrating on Afghanistan, Pakistan, and India.1 With U.S.-led counterterrorism efforts focused especially on Southwest Asia, the existence of international terrorist groups and their supporters in South Asia is identified as a threat to both regional stability and to the attainment of key U.S. policy goals. Al Qaeda forces that fled

K. Alan Kronstadt

182

The Uses of Military Force Since the Second World War.  

National Technical Information Service (NTIS)

Classification of the uses of military force since World War II by region; countries; types; levels of violence; participation by nuclear powers, industrial countries and communist powers. Plus discussion of trends in international conflict. (Author)

P. C. Oleson

1968-01-01

183

U.S. Army Special Forces Roles in Asymmetric Warfare.  

National Technical Information Service (NTIS)

The U.S. National Security Strategy is the basis of a preventive solution through global engagement, which fosters international interoperability and cooperation to defeat complex asymmetric threats. The study examined how U. S. Army Special Forces can ad...

H. P. Dinter

2001-01-01

184

77 FR 70473 - Child Labor, Forced Labor, and Forced or Indentured Child Labor in the Production of Goods in...  

Federal Register 2010, 2011, 2012, 2013

...Labor in the Production of Goods in Foreign Countries and Efforts by Certain...The Bureau of International Labor Affairs, United States Department of Labor...regarding child labor and forced labor in foreign countries. Relevant...

2012-11-26

185

77 FR 9267 - Child Labor, Forced Labor, and Forced or Indentured Child Labor in the Production of Goods in...  

Federal Register 2010, 2011, 2012, 2013

...Labor in the Production of Goods in Foreign Countries and Efforts by Certain...The Bureau of International Labor Affairs, United States Department of Labor...regarding child labor and forced labor in foreign countries. Relevant...

2012-02-16

186

Tactical force protection  

NASA Astrophysics Data System (ADS)

The need for enhanced tactical force protection capabilities is evidenced from our recent experiences in Iraq and Afghanistan and occurs wherever U.S. Forces maintain a forward presence in a potentially hostile environment. Levels of force protection proficiency vary widely from combat units whose mission is to close with and destroy the enemy to combat support/combat service support units performing maintenance and logistics functions. We must provide force protection capabilities that are not only good enough to get the job done, but affordable for the entire force. Addressing the force protection challenge requires an investment in research and development to deliver affordable, scalable, modular and sustainable force protection equipment. This can be accomplished through an evolutionary acquisition strategy of capability upgrades in the near, mid and far-terms that leverage the Army's investments in unmanned ground sensors (UGS), unmanned ground vehicles (UGV) and surveillance radar and imaging technology. This approach addresses the field's immediate tactical force protection requirements, while working towards full integration with the Future Combat System. Futuristic Tactical Force Protection will consist of a fully integrated system of systems architecture that will include UGVs, UGS and Unmanned Aerial Vehicles (UAVs) that are networked with the Future Force.

Stockel, Eugene; Moneyhun, Jon C.

2004-09-01

187

Kosovo and the Remaking of International Relations  

Microsoft Academic Search

The Kosovo Report: Conflict, International Response, Lessons Learned Independent International Commission on Kosovo Oxford University Press, 2000 HBK: ISBN: 0199243085 £35.00 PBK: ISBN: 0199243093 £11.99 pp. 372 (including: index, notes, bibliography, annexes, and map)Alliance Politics, Kosovo, and NATO's War: Alliance Force or Forced Allies? Pierre Martin and Mark R. Brawley (eds) Palgrave, 2001 HBK: ISBN: 0312238177 £32.50 pp. 246 (including:

David Chandler

2002-01-01

188

Glenohumeral contact forces in reversed anatomy shoulder replacement  

Microsoft Academic Search

A major requirement to design an implant is to develop our understanding of the applied internal forces during everyday activities. In the absence of any basic apparatus for measuring forces directly, it is essential to rely on modelling. The major aim of this study was therefore to understand the biomechanical function of subjects with the reversed anatomy Bayley?Walker prosthesis, using

Milad Masjedi; Garth R. Johnson

2010-01-01

189

Effect of Inclusions on Coercive Force of Iron  

Microsoft Academic Search

A theory is developed for the contribution to the coercive force of iron of randomly distributed non-magnetic inclusions. Two contributing effects are examined: (1) the surface tension effect, and (2) the effect of internal magnetic poles. It is found that the coercive force depends both on the total volume fraction of inclusions and the state of dispersion. For a given

L. J. Dijkstra; C. Wert

1950-01-01

190

Coulomb force as an entropic force  

SciTech Connect

Motivated by Verlinde's theory of entropic gravity, we give a tentative explanation to the Coulomb's law with an entropic force. When trying to do this, we find the equipartition rule should be extended to charges and the concept of temperature should be reinterpreted. If one accepts the holographic principle as well as our generalizations and reinterpretations, then Coulomb's law, the Poisson equation, and the Maxwell equations can be derived smoothly. Our attempt can be regarded as a new way to unify the electromagnetic force with gravity, from the entropic origin. Possibly some of our postulates are related to the D-brane picture of black hole thermodynamics.

Wang Tower [Center for High-Energy Physics, Peking University, Beijing 100871 (China)

2010-05-15

191

Physical Pendulum Forces  

NSDL National Science Digital Library

The Physical Pendulum with Forces model displays the gravitational, normal, and friction forces acting on a mass attached to a pivoted rod.  These forces cause the mass to accelerate in the radially and tangentially with respect to pivot.  Although gravity is always downward, friction and normal force change direction in order to keep the mass in the same position on the stick.  The Physical Pendulum Forces model was created using the Easy Java Simulations (EJS) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_mech_newton_PhysicalPendulumForces.jar file will run the program if Java is installed.

Christian, Wolfgang

2010-02-01

192

Force User's Manual  

Microsoft Academic Search

CONTENTSI. Introduction 1II. Description of the Force Macros: 5A. Macros Specifying Program Structure 6B. Variable Declarations 10C. Parallel Execution 13D. Synchronization 20III. Restrictions on the Force Macros 25IV. How to Invoke the Force 25A. Flex\\/32 (Flexible Computer Corp.) 26B. Multimax (Encore Computer Corp.) 27C. Balance (Sequent Computer Corp.) 28D. Alliant FX\\/Series (Alliant Computer Systems Corp.) 29E. Cray 2 (Cray Research,

Harry F. Jordan; Muhammad S. Benten; Norbert S. Arenstorf; Aruna V. Ramanan

1987-01-01

193

Geotropism: Its Orienting Force.  

PubMed

Seeds of Pisum sativum L. and other species were germinated and grown for five or more days on a continuously rotating vertical-axis turntable that developed a maximum centrifugal force of 1.79(g). Shoot (epicotyl) orientation in darkness was parallel to the resultant gravitational field. This is presented as confirmation of the hypothesis that the orienting force of geotropism of the higher plants is the inertial force of gravity. PMID:17808197

Westing, A H

1964-06-12

194

Specialization in defence forces  

Microsoft Academic Search

The choice between balanced and specialized defence forces depends on the technology of defence output (e.g. whether a force scope multiplier is present), the existence of scope and scale economies, the platform customization costs and, of course, the level of defence budgets. Minimum force element levels (thresholds), and scale economies facilitate specialization as opposed to scope economies (e.g. platform?sharing), scale

UGURHAN G. BERKOK

2005-01-01

195

International law and law enforcement firearms  

Microsoft Academic Search

Several international agreements set constraints on the legitimate use of firearms as representing lethal force. Their meaning in terms of weapons technology must take into account their operational frame of reference, and legitimate warfare can be regarded as a law enforcement operation with similar principles on the use of force. Changes in weapons technology, such as new types of ammunition,

Jorma Jussila; Pertti Normia

2004-01-01

196

Response Bias in International Marketing Research  

Microsoft Academic Search

The saturation of domestic markets in the industrialized parts of the world, combined with increased competition in home markets from foreign competitors forces many companies to look for opportunities beyond their national boundaries. Surveys are a crucial source of data in international marketing for theory building and answering managerial questions, as secondary data is seldom satisfactory. An important force that

M. G. de Jong

2006-01-01

197

Japanese Internment  

NSDL National Science Digital Library

Students will examine the decision to place all Japanese-Americans living on the West Coast into internment camps during WWII. This lesson is part of a mini-unit on Japanese Internment that will include readings in primary source documents and materials from History Alive that will provide most of the background knowledge necessary to evaluate the decision to intern Japanese-Americans during the war and the effects of internment on this group during the post-war period. This resource includes both a teaching guide and student worksheets.

Lindskog, Tom

2011-09-14

198

No fifth force?  

NASA Astrophysics Data System (ADS)

Hopes that geophysicists might be able to document a fifth force of nature have diminished, as new measurements and analyses of earlier geodetic experiments have yielded no solid evidence of a non-Newtonian component of gravity.Modern physics recognizes four fundamental forces with distinct spheres of influence: The strong and weak nuclear forces operate over the range of one atom, while gravity and electromagnetism have an infinite range. Gravity measurements over a few centimeters in laboratories and over millions of kilometers in space continue to buttress Issac Newton's conclusion that the gravitational force between two objects decreases as the square of the distance between them.

Maggs, William Ward

199

Central Force JS Model  

NSDL National Science Digital Library

The Central Force JavaScript Model computes the trajectory of a particle acted on by a central force.  The model reads uses a JavaScript mathematical expression parser to read the force and a adaptive step Runge-Kutta 5(4) algorithm to compute the trajectory.  This model is designed to test the speed of the JS parser and the accuracy of the EJS JavaScript ODE solver. The Central Force JS Model was developed using the Easy Java Simulations (EJS) version 5. It is distributed as a ready-to-run html page and requires only a browser with JavaScript support.

Christian, Wolfgang

2013-09-01

200

Glenohumeral contact forces.  

PubMed

Glenohumeral contact forces have only been calculated previously either for simple abduction or for athletic activities. The objective of this study was to determine the glenohumeral contact forces for tasks which are demanding of the shoulder but which would commonly be performed by older people. The functional tasks chosen were using the arms to stand up from and sit down into a chair, walking with a cane, lifting a 5 kg box to shoulder height with both hands, and lifting a 10 kg suitcase. The trunk angles, arm angles and hand loads of six healthy subjects, average age 55 years, were recorded. This information was input into a biomechanical computer model which optimized the muscle force distribution by minimizing the sum of squared muscle stresses subject to constraints on the maximum muscle forces and maintaining the direction of the resultant force within the glenoid fossa. Average contact forces ranged from 1.3 to 2.4 times body weight (930-1720 N), the highest force being for lifting a suitcase. This latter value would be even higher if lifting either a greater load or to a greater height. Thus, contact forces at the shoulder should not be underestimated. This study provides functionally relevant contact forces which can be used for mechanical testing or finite element modelling of shoulder prostheses. PMID:11201411

Anglin, C; Wyss, U P; Pichora, D R

2000-01-01

201

Simulation of a force on force exercise  

SciTech Connect

The Security Exercise Evaluation System (SEES) is under development for use in planning Force on Force exercises and as an aid in post-exercise evaluation. This study is part of the development cycle where the simulation results are compared to field data to provide guidance for further development of the model. SEES is an event-driven stochastic computer program simulating individual movement and combat within an urban terrain environment. The simulator models the physics of movement, line of sight, and weapon effects. It relies on the controllers to provide all knowledge of security tactics, which are entered by the controllers during the simulation using interactive color graphic workstations. They are able to develop, modify and implement plans promptly as the simulator maintains real time. This paper reports on how SEES will be used to develop an intrusion plan, test the security response tactics and develop observer logistics. A Force on Force field exercise will then be executed to follow the plan with observations recorded. An analysis is made by first comparing the plan and events of the simulation with the field exercise, modifying the simulation plan to match the actual field exercise, and then running the simulation to develop a distribution of possible outcomes.

Terhune, R.; Van Slyke, D.; Sheppard, T.; Brandrup, M.

1988-01-01

202

Security Force Assistance.  

National Technical Information Service (NTIS)

In an era of persistent conflict, the United States supports the internal defense and development of international partners, regardless of whether those partners are highly developed and stable or less developed and emerging. While many of these partners ...

M. E. Dempsey

2009-01-01

203

Internalized activities  

Microsoft Academic Search

This paper argues that interactive mental processes in humans have a natural tendency to replay internally and cyclically, a typical example being the tunes that run ‘in our head’ for hours. The existence of these ‘internalized activities’ may be shown by both simple introspection and neurological experiments, which also reveal that they occur in all sensory modalities and involve everything

Jean-Christophe Buisson; Jean-Charles Quinton

2010-01-01

204

International Indirection.  

ERIC Educational Resources Information Center

|Criticizes the Library of Congress' manner of representing the United States in international attempts to develop universal bibliographic control. Direct involvement by American libraries in international activities is urged, in order that actions taken be decided upon in a democratic fashion. (SW)|

Malinconico, S. Michael

1979-01-01

205

Physclips: Coriolis Forces  

NSDL National Science Digital Library

This web page provides an introduction to coriolis forces. It includes topics such as the motion of wind and ocean currents, the rotation of the Earth, and forces. Diagrams are integrated with text to promote understanding of important concepts. This tutorial is part of the PhysClip collection of web-based resources on introductory mechanics, electricity, and magnetism.

Wolfe, Joe

2009-06-18

206

Lathe tool force.  

National Technical Information Service (NTIS)

This report describes a computer program that computes the forces exerted on a lathe tool as a part is being machined. The program is based on a mechanistic model which assumes that the normal force on the tool face is proportional to the cross-sectional ...

J. D. Emery

1993-01-01

207

Elementary Particles and Forces.  

ERIC Educational Resources Information Center

|Discusses subatomic particles (quarks, leptons, and others) revealed by higher accelerator energies. A connection between forces at this subatomic level has been established, and prospects are good for a description of forces that encompass binding atomic nuclei. Colors, fundamental interactions, screening, camouflage, electroweak symmetry, and…

Quigg, Chris

1985-01-01

208

Understanding Force and Motion  

NSDL National Science Digital Library

The objects will not change position from their initial rest positions because the downward force on each side of the pulley (ignoring the weight of the string) is the same and the net force on each side of the pulley is zero. The gravitational attraction

Haysom, John; Bowen, Michael

2010-10-01

209

'Total Force' Comptroller.  

National Technical Information Service (NTIS)

The Air Reserve Forces are the initial and primary source of augmentation of the active forces during war or an emergency. However, the roles and missions of ARF comptroller personnel have not yet been defined. Actions to determine the most effective use ...

K. R. Boerum

1985-01-01

210

Force & Motion Microworld  

Microsoft Academic Search

This program is intended to help students develop a conceptual qualitative understanding of the relations between force and motion and to confront their alternative conceptions in this domain. Force & Motion Microworld consists of four topics: Motion Graphs: understanding of velocity - time graphs Spaceship: linear frictionless horizontal motion Model Car: linear horizontal motion with friction Skydiver: vertical (downward) motion

Miky Ronen

1999-01-01

211

Force Modulator System  

Microsoft Academic Search

Many metal parts manufacturers use large metal presses to shape sheet metal into finished products like car body parts, jet wing and fuselage surfaces, etc. These metal presses take sheet metal and - with enormous force - reshape the metal into a fully formed part in a manner of seconds. Although highly efficient, the forces involved in forming metal parts

Redmond Clark

2009-01-01

212

Force concept inventory  

NSDL National Science Digital Library

This article reports the rationale, design, validation, and uses of the "Force Concept Inventory," an instrument to assess students' beliefs on force. Results and implications of two studies that compared the inventory with the "Mechanics Baseline" are included. The article includes a copy of the instrument.

Hestenes, David; Wells, Malcolm; Swackhamer, Gregg

2005-10-27

213

About Forces of Flight  

NSDL National Science Digital Library

"Forces of Flight," is a Boeing program created to help classroom teachers excite and engage students about science. Student inquiry is promoted by linking information on posters and the web site to a series of classic hands-on physics experiments that demonstrate the forces of flight.

Http://www.boeing.com

2009-02-12

214

Force, mass and acceleration  

Microsoft Academic Search

Force, mass and acceleration are everyday words but often used inaccurately. Force is a physical influence, which when applied to an object causes it to accelerate in the direction from which it was applied. Mass is the amount of matter in an object and is expressed in kilograms. Acceleration is the rate of change of velocity of an object in

Phil Dalrymple; Richard Griffiths

2005-01-01

215

International Water Association  

NSDL National Science Digital Library

A worldwide organization of water professionals, the International Water Association's (IWA) Web site illustrates its commitment "to help water professionals create innovative, pragmatic, and sustainable solutions to challenging global water needs." Visitors can discover IWA's many activities from conferences and forums to task forces. Researchers can discover the various IWS groups that specialize in topics including Source Management, Education, Health, Management Training, and Water Quality Management. Although many of the publications are restricted to members, educators and students can read reports from the Sustainability in Water Sector and abstracts from IWA journals.

2003-01-01

216

China's energy security: Domestic and international issues  

Microsoft Academic Search

Runaway growth in energy consumption poses a real threat to China's energy security. The era of Chinese energy independence is gone, along with the ide- ology of self-reliance as a viable guide for energy policymaking. In particular, China's thirst for oil forces Beijing to aggressively pursue international sources of supply, driving up international oil prices. High oil prices not only

Zha Daojiong

2006-01-01

217

INTERNATIONAL SETTLEMENTS: AN ANALYSIS OF RATES  

Microsoft Academic Search

In the late 1970s, when competition was introduced in the United States, competitive forces pushed international telephone prices down. Lower prices resulted, inter alia, in an increase in international calls and minutes from the United States to countries whose prices were high relative to United States prices. This increase in minute volume in turn resulted in a significant increase in

James Alleman

1998-01-01

218

Imaging adhesion forces on proteins with the atomic force microscope  

Microsoft Academic Search

We investigated the adhesion forces between single protein molecules and the silicon-nitride tip of an atomic force microscope. Force curves were taken on a sample with single adsorbed proteins while the tip was raster scanned laterally. Out of these force maps we can calculate several images showing for instance the topography or the adhesion force as a function of lateral

Manfred Radmacher; Monika Fritz; Miriam W. Allersma; Christoph F. Schmidt; Paul K. Hansma

1995-01-01

219

Optical measurement of mechanical forces inside short DNA loops.  

PubMed

Knowledge of the mechanical properties of double-stranded DNA (dsDNA) is essential to understand the role of dsDNA looping in gene regulation and the mechanochemistry of molecular machines that operate on dsDNA. Here, we use a newly developed tool, force sensors with optical readout, to measure the forces inside short, strained loops composed of both dsDNA and single-stranded DNA. By varying the length of the loops and their proportion of dsDNA, it was possible to vary their internal forces from 1 pN to >20 pN. Surprisingly, internal loop forces changed erratically as the amount of dsDNA was increased for a given loop length, with the effect most notable in the smallest loop (57 nucleotides). Monte Carlo simulations based on the helical wormlike chain model accurately predict internal forces when more than half of the loop is dsDNA but fail otherwise. Mismatches engineered into the double-stranded regions increased flexibility, suggesting that Watson-Crick basepaired dsDNA can withstand high compressive forces without recourse to multibase melts. Fluorescence correlation spectroscopy further excluded transient melting (microsecond to millisecond duration) as a mechanism for relief of compressive forces in the tested dsDNAs. DNA loops with integrated force sensors may allow the comprehensive mapping of the elasticity of short dsDNAs as a function of both sequence and salt. PMID:18065484

Shroff, Hari; Sivak, David; Siegel, Jake J; McEvoy, A L; Siu, Merek; Spakowitz, Andrew; Geissler, Phillip L; Liphardt, Jan

2007-12-07

220

Optical Measurement of Mechanical Forces Inside Short DNA Loops  

PubMed Central

Knowledge of the mechanical properties of double-stranded DNA (dsDNA) is essential to understand the role of dsDNA looping in gene regulation and the mechanochemistry of molecular machines that operate on dsDNA. Here, we use a newly developed tool, force sensors with optical readout, to measure the forces inside short, strained loops composed of both dsDNA and single-stranded DNA. By varying the length of the loops and their proportion of dsDNA, it was possible to vary their internal forces from 1 pN to >20 pN. Surprisingly, internal loop forces changed erratically as the amount of dsDNA was increased for a given loop length, with the effect most notable in the smallest loop (57 nucleotides). Monte Carlo simulations based on the helical wormlike chain model accurately predict internal forces when more than half of the loop is dsDNA but fail otherwise. Mismatches engineered into the double-stranded regions increased flexibility, suggesting that Watson-Crick basepaired dsDNA can withstand high compressive forces without recourse to multibase melts. Fluorescence correlation spectroscopy further excluded transient melting (microsecond to millisecond duration) as a mechanism for relief of compressive forces in the tested dsDNAs. DNA loops with integrated force sensors may allow the comprehensive mapping of the elasticity of short dsDNAs as a function of both sequence and salt.

Shroff, Hari; Sivak, David; Siegel, Jake J.; McEvoy, A. L.; Siu, Merek; Spakowitz, Andrew; Geissler, Phillip L.; Liphardt, Jan

2008-01-01

221

Dynamic Force Generation by Neural Stem Cells  

PubMed Central

Mechanical cues may have important roles in tissue morphogenesis; progression through complex functions like differentiation may be associated with changes in cellular force generation and mechanosensing. To explore this concept, we use elastomer pillar arrays to map forces generated by neural stem cells in vitro, and identify two distinct dynamics of force generation. First, cell generated forces decrease as cells transition from a proliferative mode to differentiation, a process covering several days. This change in force generation correlated with a loss of sensitivity to substrate rigidity over a series of polydimethylsiloxane substrates. Second, neural stem cells exhibit a faster pattern of localized contractions at the cell body and outlying processes; each lasts on the order of minutes, and is not synchronized across the cell. This faster process is reminiscent of migratory behavior observed in vivo, and may be involved in controlling the motion of internal structures such as the cell nucleus. These results together provide new clues into the role of forces during development, and may lead to design principles for materials targeted for use in the central nervous system.

Shi, P.; Shen, K.; Ghassemi, S.; Hone, J.; Kam, L.C.

2010-01-01

222

The evolution of NATO's conventional force posture  

SciTech Connect

This dissertation has three objectives. The first is to describe the evolution of NATO's conventional force posture in greater detail than has previously been possible by drawing upon recently declassified government documents. The author's focus is on changes that have occurred in the role of conventional forces in NATO strategy as well as in the structure and actual capabilities of NATO's conventional forces. He examines five episodes in NATO history during which significant change in the alliance's conventional forces was seriously contemplated, attempted, or actually took place. The second objective is to explain this history. To this end, he examines several leading theories of international relations: balance of power and balance of threat, public goods, and regimes. By comparing the predictions of these theories with the historical record, he was able to identify the factors most important in shaping NATO's conventional force posture over the years. Since these factors are likely to continue to be important, this analysis allows assessing prospects for future change, the third objective. This study suggests that NATO's conventional force posture has become increasingly static over the years.

Duffield, J.S.

1989-01-01

223

OOTW Force Design Tools  

SciTech Connect

This report documents refined requirements for tools to aid the process of force design in Operations Other Than War (OOTWs). It recommends actions for the creation of one tool and work on other tools relating to mission planning. It also identifies the governmental agencies and commands with interests in each tool, from whom should come the user advisory groups overseeing the respective tool development activities. The understanding of OOTWs and their analytical support requirements has matured to the point where action can be taken in three areas: force design, collaborative analysis, and impact analysis. While the nature of the action and the length of time before complete results can be expected depends on the area, in each case the action should begin immediately. Force design for OOTWs is not a technically difficult process. Like force design for combat operations, it is a process of matching the capabilities of forces against the specified and implied tasks of the operation, considering the constraints of logistics, transport and force availabilities. However, there is a critical difference that restricts the usefulness of combat force design tools for OOTWs: the combat tools are built to infer non-combat capability requirements from combat capability requirements and cannot reverse the direction of the inference, as is required for OOTWs. Recently, OOTWs have played a larger role in force assessment, system effectiveness and tradeoff analysis, and concept and doctrine development and analysis. In the first Quadrennial Defense Review (QDR), each of the Services created its own OOTW force design tool. Unfortunately, the tools address different parts of the problem and do not coordinate the use of competing capabilities. These tools satisfied the immediate requirements of the QDR, but do not provide a long-term cost-effective solution.

Bell, R.E.; Hartley, D.S.III; Packard, S.L.

1999-05-01

224

Amnesty International  

NSDL National Science Digital Library

The Amnesty International Web site offers the full text of the Universal Declaration of Human Rights adopted by the United Nations General Assembly in 1948, the organizations goals and activities, and membership information.

225

ILO - International Migration Programme.  

PubMed

In a wide International Context characterised not only by the economical development but also by the social, cultural, political and individual development, we witness more and more to a exchange between the developed and the developing countries, which can be translated especially in the migration of the work force. In theory, all countries are either countries of origin either countries of transit or destination, and they are all responsible for the rights of migrant workers by promoting the rights, by monitoring and by preventing the abusive conditions. The process of migration of the workforce can be divided into three stages: the first coincides with the period prior to departure, the second is represented by the aftermath of the departure and the period of stay in the country of destination, the third stage corresponds to the return in the country of origin. The workers must be protected throughout this process by the international organizations that perform the catalytic role of communication and exchange between countries, for the only purpose of protecting the rights of immigrant and/or immigrants workers. The responsibility for the protection of workers is divided among the various players in the International Labour Organisation. Every country has to apply measures according to the international standards regarding workers' rights, standards that guide the various countries in the formulation and implementation of their policies and legislation. These standards are suggested by International Conventions, the ILO Conventions and other international instruments such as the human rights instrument. There has been a big step forward once the ILO Fundamental Conventions and Conventions on Migrant Workers where implemented and this implementation represented the use of the Guidelines "ILO Multilateral Framework on Labour Migration". PMID:22073693

Boudraa, Miriam

226

International dimensions of Colombian violence.  

PubMed

Violence is the main public health problem in Colombia, as demonstrated by current homicide rates (the highest in the world), the strong effect of violence on the health care sector, and the forceful displacement of citizens, among other factors. This violence has international dimensions and consequences: inequity resulting from the political-economic system and increased by the neoliberal adjustments; the international traffic of drugs and weapons; exile and forceful displacement of persons into bordering countries; and frequent violations of human rights and humanitarian international rights. The international community can play a role in the search for a solution to this problem, as the author discusses in terms of contributions made in the past and those that could be made in the near future. Colombian violence can be viewed as a problem, a message, and a challenge for international public health, and the author suggests specific areas in which international public health could contribute to the study and solution of this complex situation. PMID:10707304

Franco, S

2000-01-01

227

Diamagnetic forces in superconducting magnets  

Microsoft Academic Search

We have previously reported damage to two large superconducting solenoids caused by axial expansion forces and radial compression forces. These forces, which can be greater than and are of opposite sense to the classical Lorentz forces, we have attributed to the diamagnetism of the composite superconductors. Some irregularities experienced in the operation of force cooled superconducting magnet systems appear to

R. Stevenson; D. Atherton

1975-01-01

228

Motion and Forces  

NSDL National Science Digital Library

This self-contained module on motion and forces includes a range of fun activities that students can perform in the classroom and at home with family members. They impart important concepts such as observation, identification, measurement, and differentiation.

Science, Houghton M.

229

Quantized Casimir Force  

NASA Astrophysics Data System (ADS)

We investigate the Casimir effect between two-dimensional electron systems driven to the quantum Hall regime by a strong perpendicular magnetic field. In the large-separation (d) limit where retardation effects are essential, we find (i) that the Casimir force is quantized in units of 3?c?2/8?2d4 and (ii) that the force is repulsive for mirrors with the same type of carrier and attractive for mirrors with opposite types of carrier. The sign of the Casimir force is therefore electrically tunable in ambipolar materials such as graphene. The Casimir force is suppressed when one mirror is a charge-neutral graphene system in a filling factor ?=0 quantum Hall state.

Tse, Wang-Kong; MacDonald, A. H.

2012-12-01

230

Forces in Motion.  

ERIC Educational Resources Information Center

Describes an activity to give students experience with the variables and forces impacting a moving body on an inclined plane by observing a ball as it rolls down an inclined PVC pipe of fixed length. Includes a student worksheet. (MKR)

Goodsell, David; And Others

1995-01-01

231

Globalization Task Force Report.  

National Technical Information Service (NTIS)

Since the last meeting of the President's National Security Telecommunications Advisory Committee (NSTAC) in June 1999, the Globalization Task Force (GTF)1 has concentrated its efforts on national security and emergency preparedness (NS/EP) issues related...

2000-01-01

232

Forces in Motion.  

ERIC Educational Resources Information Center

|Describes an activity to give students experience with the variables and forces impacting a moving body on an inclined plane by observing a ball as it rolls down an inclined PVC pipe of fixed length. Includes a student worksheet. (MKR)|

Goodsell, David; And Others

1995-01-01

233

Five-Forces-Modell  

Microsoft Academic Search

\\u000a Das Five-Forces-Modell von Porter umfasst fünf Elemente (Lieferanten, neue Wettbewerber, Kunden, Substitutionsprodukte, Branchenwettbewerb),\\u000a anhand derer ein Unternehmen die Attraktivität eines Marktes analysieren kann.

Christian Schawel; Fabian Billing

234

Five-Forces-Modell  

Microsoft Academic Search

Das Five-Forces-Modell von Porter umfasst fünf Elemente (Lieferanten, neue Wettbewerber, Kunden, Substitutionsprodukte, Branchenwettbewerb),\\u000a anhand derer ein Unternehmen die Attraktivität eines Marktes analysieren kann.

Christian Schawel; Fabian Billing

235

Tube Crossflow Force Measurements.  

National Technical Information Service (NTIS)

A transducer has been designed and verified which has the potential for measuring lift and drag forces on circular rods in turbulent cross flow. The transducer is currently being used to obtain data. (ERA citation 08:023541)

T. M. Mulcahy

1981-01-01

236

Force Feedback Joystick.  

National Technical Information Service (NTIS)

I-FORCE, a computer peripheral from Immersion Corporation, was derived from virtual environment and human factors research at the Advanced Displays and Spatial Perception Laboratory at Ames Research Center in collaboration with Stanford University Center ...

1997-01-01

237

Relativistic linear restoring force  

NASA Astrophysics Data System (ADS)

We consider two different forms for a relativistic version of a linear restoring force. The pair comes from taking Hooke’s law to be the force appearing on the right-hand side of the relativistic expressions: dp/dt or dp/d?. Either formulation recovers Hooke’s law in the non-relativistic limit. In addition to these two forces, we introduce a form of retardation appropriate for the description of a linear (in displacement) force arising from the interaction of a pair of particles with a relativistic field. The procedure is akin to replacing Coulomb’s law in electromagnetism with a retarded form (the first correction in the full relativistic case). This retardation leads to the expected oscillation, but with amplitude growth in both its relativistic and non-relativistic incarnations.

Clark, D.; Franklin, J.; Mann, N.

2012-09-01

238

Optical Bernoulli forces  

NASA Astrophysics Data System (ADS)

By Bernoulli's law, an increase in the relative speed of a fluid around a body is accompanied by a decrease in the pressure. Therefore, a rotating body in a fluid stream experiences a force perpendicular to the motion of the fluid because of the unequal relative speed of the fluid across its surface. It is well known that light has a constant speed irrespective of the relative motion. Does a rotating body immersed in a stream of photons experience a Bernoulli-like force? We show that, indeed, a rotating dielectric cylinder experiences such a lateral force from an electromagnetic wave. In fact, the sign of the lateral force is the same as that of the fluid-mechanical analog as long as the electric susceptibility is positive (?>?0), but for negative-susceptibility materials (e.g., metals) we show that the lateral force is in the opposite direction. Because these results are derived from a classical electromagnetic scattering problem, Mie-resonance enhancements that occur in other scattering phenomena also enhance the lateral force.

Movassagh, Ramis; Johnson, Steven G.

2013-08-01

239

A simple force platform.  

PubMed

The force platform consists of a sandwhich of steel, Rockwool and concrete plates about 900 X 700 mm in surface. Four steel rings were bolted to the under side of the steel plate in each corner. Each steel ring was furnished with only one strain gauge, two of which were placed on the outer- respectively on the inner side of each ring. The four strain gauges were connected to a measuring bridge. Before mounting the rings on the steel plate, the sensitivity to pressure of each ring was adjusted in such a way that they were all similar. Because of this the platform responded with a signal which was independent of where a pressure was applied within the surface of the platform. The platform showed a rectilinear response for static forces up to 500 kp with a stable zero value. In response to dynamic forces the platform showed a resononance frequency of about 50 Hz, with a damping factor of 0.15. Calibration of dynamic forces was carried out by calculation of the forces during a vertical jump compared with what would be expected from the time of flight also registered by the platform-measuring-bridge-ink-writer-set-up. The time of flight was significantly higher (11%) than exected from the time-force relations beforetake-off. This was esplained partly by the relatively low damping factor in the system, partly by the subjects not extending their knees at landing on the platform. PMID:1149732

Bonde-Petersen, F

1975-01-01

240

Processes of Internal and International Migration from Chitwan, Nepal  

PubMed Central

In this study we examine which factors predict internal and international migration from Chitwan, a flat valley located in the South-Central region of Nepal, seeking to measure the effect of theoretically specified variables such as human capital, social capital, physical capital, and neighborhood socioeconomic conditions while controlling for demographic variables. We use data from the Chitwan Valley Family Study (CVFS) to estimate a series of discrete time event history models of first and repeat migration to three competing destinations: other locations within Chitwan, other districts within Nepal, and places outside of Nepal. Results support hypotheses derived from neoclassical economics, the theory of new economics of migration, social capital theory, and cumulative causation theory. Our results underscore the need for a synthetic theoretical model that incorporates factors operating at the individual, household, and community levels. The use of multiple explanatory models yields a clearer picture of the forces driving internal and international migration from rural districts in developing nations such as Nepal.

Bohra, Pratikshya; Massey, Douglas S.

2011-01-01

241

Force Identification from Structural Response.  

National Technical Information Service (NTIS)

Force identification is a type of system identification procedure which determines applied forces from system response measurements. To identify the force, one can consider the system model and parameters which are known, and then use the response that is...

T. J. Kreitinger

1990-01-01

242

Force Identification from Structural Response.  

National Technical Information Service (NTIS)

Force identification is a type of system identification procedure which determines applied forces from system response measurements. To identify the force, one can consider the system model and known parameters, and then use the measured response to deter...

T. J. Kreitinger

1990-01-01

243

International occupational health.  

PubMed

Working conditions for the majority of the world's workers do not meet the minimum standards and guidelines set by international agencies. Occupational health and safety laws cover only about 10 percent of the population in developing countries, omitting many major hazardous industries and occupations. With rare exception, most countries defer to the United Nations the responsibility for international occupational health. The UN's international agencies have had limited success in bringing occupational health to the industrializing countries. The International Labor Organization (ILO) conventions are intended to guide all countries in the promotion of workplace safety and in managing occupational health and safety programs. ILO conventions and recommendations on occupational safety and health are international agreements that have legal force only if they are ratified by ILO member states. The most important ILO Convention on Occupational Safety and Health has been ratified by only 37 of the 175 ILO member states. Only 23 countries have ratified the ILO Employment Injury Benefits Convention that lists occupational diseases for which compensation should be paid. The World Health Organization (WHO) is responsible for the technical aspects of occupational health and safety, the promotion of medical services and hygienic standards. Limited WHO and ILO funding severely impedes the development of international occupational health. The U.S. reliance on international agencies to promote health and safety in the industrializing countries is not nearly adequate. This is particularly true if occupational health continues to be regarded primarily as an academic exercise by the developed countries, and a budgetary triviality by the international agencies. Occupational health is not a goal achievable in isolation. It should be part of a major institutional development that touches and reforms every level of government in an industrializing country. Occupational health and safety should be brought to industrializing countries by a comprehensive consultative program sponsored by the United States and other countries that are willing to share the burden. Occupational health and safety program development is tied to the economic success of the industrializing country and its industries. Only after the development of a successful legal and economic system in an industrializing country is it possible to incorporate a successful program of occupational health and safety. PMID:12971685

LaDou, Joseph

2003-08-01

244

Permeability of continental crust influenced by internal and external forcing  

Microsoft Academic Search

The permeability of continental crust is so highly variable that it is often considered to defy systematic character- ization. However, despite this variability, some order has been gleaned from globally compiled data. What accounts for the apparent coherence of mean permeability in the continental crust (and permeability-depth rela- tions) on a very large scale? Here we argue that large-scale crustal

S. A. R OJSTACZER; S. E. IN; GEB RIT

245

International Differences in Male Wage Inequality: Institutions versus Market Forces  

Microsoft Academic Search

While changes in the demand for skilled labor appear to have led to a widening of the wage structures in many countries during the 198Os,considerable differences in the level of wage inequality remain. In this paper, we examine the sources of these differences, focusing primarily on explaining the considerably higher level of wage inequality in the U.S. We find that

Francine D. Blau; Lawrence M. Kahn

1996-01-01

246

Family values and labor force participation: Ireland in international perspective  

Microsoft Academic Search

The large-scale entry of married women into the workforce has been a striking feature of the post-war period, particularly\\u000a in the United States, Britain, and other Anglo-Celtic nations. Theory implies that this should happen in all developed nations.\\u000a But there is a counter-example: Ireland. To discover whether this is truly an exception, we analyze data from large, representative\\u000a samples of

M. D. R. Evans; Jonathan Kelley; Bernadette C. Hayes

1999-01-01

247

Flow Visualization of Forced and Natural Convection in Internal Cavities  

SciTech Connect

The report descries innovative flow visualization techniques, fluid mechanics measurements and computational models of flows in a spent nuclear fuel canister. The flow visualization methods used a fluid that reacted with a metal plate to show how a local reaction affects the surrounding flow. A matched index of refraction facility was used to take mean flow and turbulence measurements within a generic spent nuclear fuel canister. Computational models were also made of the flow in the canister. It was determined that the flow field in the canister was very complex, and modifications may need to be made to ensure that the spent fuel elements are completely passivated.

John Crepeau; Hugh M. Mcllroy,Jr.; Donald M. McEligot; Keith G. Condie; Glenn McCreery; Randy Clarsean; Robert S. Brodkey; Yann G. Guezennec

2002-01-31

248

Traction Forces exerted by crawling cells  

NASA Astrophysics Data System (ADS)

We measure the forces exerted by Dictyostelium discoideum cells crawling over a deformable substrate from the displacements of fluorescent beads embedded in it. A particle tracking technique similar to PIV is used to obtain the displacements. From them, forces are computed by solving the elasto-static equation in a finite thickness slab. We will show that the finite thickness of the substrate and the distance of the beads to its surface affect substantially the results, although previous traction cytometry techniques neglected them. The measured forces are correlated to the different stages of the crawling cycle for various cell strains. It has been observed that a large fraction of the forces measured on the substrate are originated by the cell's internal tension through all the stages of motion, including the protrusion of pseudopods. This result suggests that the viscous drag exerted by the fluid in which the cells are immersed is very small compared to the forces applied by the cytoskeleton on the substrate.

Alonso-Latorre, Baldomero; Del Alamo, Juan C.; Rodriguez-Rodriguez, Javier; Aliseda, Alberto; Meili, Rudolph; Firtel, Richard; Lasheras, Juan C.

2006-11-01

249

Internal Resistance  

Microsoft Academic Search

THE following method of measuring the internal resistance of a battery was devised some two years ago by Lieut. A. R. Conden, United States Navy, then attached to this station as Instructor in Electricity. It fulfils quite closely the conditions indicated by Clerk Maxwell on p. 412, vol. i. of his treatise on Electricity and Magnetism. As it is not

C. F. Goodrich

1879-01-01

250

Fulbright Internationalism  

Microsoft Academic Search

In 1946 Senator J. William Fulbright introduced and guided through Congress legislation establishing an international exchange pro gram in education. The Fulbright program, which has produced the largest migration of students and scholars in modern history, was the result first of the senator's personal experience. His goal was to make available to thousands the enlightening experience of foreign study and

Randall Bennett Woods

1987-01-01

251

Weak Nuclear Forces cause the Strong Nuclear Force  

SciTech Connect

We determine the strength of the weak nuclear force which holds the lattices of the elementary particles together. We also determine the strength of the strong nuclear force which emanates from the sides of the nuclear lattices. The strong force is the sum of the unsaturated weak forces at the surface of the lattices.

Koschmieder, E. L. [Center for Statistical Mechanics, University of Texas at Austin, Austin TX 78712 (United States)

2008-05-29

252

Police use of force and the cumulative force factor  

Microsoft Academic Search

Purpose – This paper aims to build on and contribute to earlier studies on use of force by the police, and examines both officer and suspect force levels during altercations. Design\\/methodology\\/approach – Prior attempts to study non-lethal force have only recently begun to examine the multiple levels of force that may be used within a single encounter, advocating the use

Ross Wolf; Charlie Mesloh; Mark Henych; L. Frank Thompson

2009-01-01

253

International Education in Systemic Educational Reforms: The Chinese Case and Lessons Learned from an International Perspective  

ERIC Educational Resources Information Center

|International research findings and country experiences prove that, in coping with the tension between the global and the local in education, three major forces contribute to the success of international reform: firstly, the national public authorities in protecting education as a common good through political commitment and policy actions;…

Zhou, Nanzhao

2007-01-01

254

An Investigation of Internal Resonance in Aeroelastic Systems  

Microsoft Academic Search

Although the study of internal resonance in mechanical systems has been given significant consideration, minimal attention has been given to internal resonance for systems which consider the presence of aerodynamic forces. Herein, the investigators examine the possible existence of internal resonances, and the related nonlinear pathologies that such responses may have, for an aeroelastic system which possesses nonlinear aerodynamic loads.

Heather C. Gilliatt; Thomas W. Strganac; Andrew J. Kurdila

2003-01-01

255

47 CFR 80.86 - International regulations applicable.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false International regulations applicable. 80.86...Procedures-General § 80.86 International regulations applicable. In...and the radio provisions of all other international agreements in force to which the...

2011-10-01

256

Teaching International Law: Concepts in International Relations  

ERIC Educational Resources Information Center

|This book is designed to introduce students to public international law. Topics covered include international public organizations, such as the United Nations and World Trade Organization, international courts, international human rights law, international trade law, and international environmental law. The goal of each study is to examine how…

Starbird, Caroline; Pettit, Jenny; Singleton, Laurel

2004-01-01

257

Teaching International Law: Concepts in International Relations  

ERIC Educational Resources Information Center

This book is designed to introduce students to public international law. Topics covered include international public organizations, such as the United Nations and World Trade Organization, international courts, international human rights law, international trade law, and international environmental law. The goal of each study is to examine how…

Starbird, Caroline; Pettit, Jenny; Singleton, Laurel

2004-01-01

258

Optical force stamping lithography.  

PubMed

Here we introduce a new paradigm of far-field optical lithography, optical force stamping lithography. The approach employs optical forces exerted by a spatially modulated light field on colloidal nanoparticles to rapidly stamp large arbitrary patterns comprised of single nanoparticles onto a substrate with a single-nanoparticle positioning accuracy well beyond the diffraction limit. Because the process is all-optical, the stamping pattern can be changed almost instantly and there is no constraint on the type of nanoparticle or substrates used. PMID:21992538

Nedev, Spas; Urban, Alexander S; Lutich, Andrey A; Feldmann, Jochen

2011-10-17

259

Image Force Microscopy  

NASA Astrophysics Data System (ADS)

In this thesis we describe an enhancement to the Atomic force microscope (AFM) to simultaneously gather topographic features and spectroscopic information .Compared to the current state of the art of near-field excitation and far-field detection AFM imaging techniques our system uses a radical new approach near-field excitation and near-field detection. By placing the detector in the near-field we achieve high signal to noise and single molecular resolution. The origin of our near-field detector signal is the image force gradient due to the interaction of the stimulated molecular dipole with its image on the metal probe. We designed and built an optical and electronic system to capture this signal and simultaneously image nano-scale surface topography and optical image force gradient. By varying the wavelength of the excitation beam we measure the induced optical image force gradient spectra of molecules on surface. These spectra show good agreement with the absorption spectra of the bulk molecules measured by conventional absorption spectroscopy. We show that image force gradient is directly proportional to the optical absorption dipole strength. Using Finite Element 3D electromagnetic simulations and using Lorentz model for the excited molecular dipole we showed that the image force gradient has a decay length of 1nm, making the theoretical resolution of this microscopy technique approximately 1 nm. This rapid decay was measured experimentally .This resolution was seen by the high contrasting spectroscopic images of molecules on the surface. In follow on experiments this technique was extended to provide surface Raman spectroscopy and microscopy at molecular resolution. We create an image force gradient interaction through optical parametric down conversion between stimulated Raman excited molecules on a surface and a cantilevered nanometer scale probe brought very close to it. Spectroscopy and microscopy on clusters of molecules have been performed. Single molecules within such clusters are clearly resolved in the Raman micrographs. Raman spectra of amino acid Phenylalanine was obtained this the first time the Raman effect has been detected through a force interaction.

Rajapaksa, Indrajith

260

Ferromagnetic Resonance Force Microscopy  

Microsoft Academic Search

The magnetic resonance force microscope (MRFM) is a novel scanning probe instrument that combines the three-dimensional imaging\\u000a capabilities of magnetic resonance imaging (MRI) with the high sensitivity and resolution of atomic force microscopy (AFM).\\u000a In the nuclear magnetic resonance (NMR) mode or the electron spin resonance (ESR) mode it will enable nondestructive, chemical-specific,\\u000a high-resolution microscopic studies and imaging of subsurface properties of a broad range of

Philip E. Wigen; Michael L. Roukes; Peter C. Hammel

261

Balkans Task Force  

NSDL National Science Digital Library

UNEP, the United Nations Environment Programme, launched the Balkans Task Force (BTF) Website on May 5, 1999 to provide information and updates on "the environmental and human settlements impacts of the ongoing Balkans conflict." Experts from the Balkans Task Force visit war-damaged (industrial) sites and post their results in a series of online Situation Reports; currently, fourteen reports (in HTML or .pdf) are available on-site. Also provided are regional maps, general information, related news and documents, and a series of links to other Websites featuring aspects of the Kosovo conflict.

262

Forces and Graphing  

NSDL National Science Digital Library

This activity can be used to explore forces acting on an object, to practice graphing experimental data, and/or to introduce the algebra concepts of slope and intercept of a line. A wooden 2x4 beam is set on top of two scales. Students learn how to conduct an experiment by applying loads at different locations along the beam, recording the exact position of the applied load and the reaction forces measured by the scales at each end of the beam. In addition, students will analyze the experiment data with the use of a chart and a table and model linear equations to describe relationships between independent and dependent variables.

Center For Engineering And Computing Education

263

Coordination of Contact Forces During Multifinger Static Prehension  

PubMed Central

This study investigated the effects of modifying contact finger forces in one direction—normal or tangential—on the entire set of the contact forces, while statically holding an object. Subjects grasped a handle instrumented with finger force-moment sensors, maintained it at rest in the air, and then slowly: (1) increased the grasping force, (2) tried to spread fingers apart, and (3) tried to squeeze fingers together. Analysis was mostly performed at the virtual finger (VF) level (the VF is an imaginable finger that generates the same force and moment as the four fingers combined). For all three tasks there were statistically significant changes in the VF normal and tangential forces. For finger spreading/squeezing the tangential force neutral point was located between the index and middle fingers. We conclude that the internal forces are regulated as a whole, including adjustments in both normal and tangential force, instead of only a subset of forces (normal or tangential). The effects of such factors as EFFORT and TORQUE were additive; their interaction was not statistically significant, thus supporting the principle of superposition in human prehension.

Martin, Joel R.; Latash, Mark L.

2011-01-01

264

Antiphospholipid Syndrome Clinical Research Task Force report.  

PubMed

The Antiphospholipid Syndrome (APS) Clinical Research Task Force (CRTF) was one of six Task Forces developed by the 13(th) International Congress on Antiphospholipid Antibodies (aPL) organization committee with the purpose of: a) evaluating the limitations of APS clinical research and developing guidelines for researchers to help improve the quality of APS research; and b) prioritizing the ideas for a well-designed multicenter clinical trial and discussing the pragmatics of getting such a trial done. Following a systematic working algorithm, the Task Force identified five major issues that impede APS clinical research and the ability to develop evidence-based recommendations for the management of aPL-positive patients: (1) aPL detection has been based on partially or non-standardized tests, and clinical (and basic) APS research studies have included patients with heterogeneous aPL profiles with different clinical event risks; (2) clinical (and basic) APS research studies have included a heterogeneous group of patients with different aPL-related manifestations (some controversial); (3) thrombosis and/or pregnancy risk stratification and quantification are rarely incorporated in APS clinical research; (4) most APS clinical studies include patients with single positive aPL results and/or low-titer aPL ELISA results; furthermore, study designs are mostly retrospective and not population based, with limited number of prospective and/or controlled population studies; and (5) lack of the understanding the particular mechanisms of aPL-mediated clinical events limits the optimal clinical study design. The Task Force recommended that there is an urgent need for a truly international collaborative approach to design and conduct well-designed prospective large-scale multi-center clinical trials of patients with persistent and clinically significant aPL profiles. An international collaborative meeting to formulate a good research question using 'FINER' (Feasible; Interesting; Novel; Ethical; and Relevant) criteria took place in November 2010. PMID:21303838

Erkan, D; Derksen, R; Levy, R; Machin, S; Ortel, T; Pierangeli, S; Roubey, R; Lockshin, M

2011-02-01

265

Wettability: Fundamentals and Surface Forces  

Microsoft Academic Search

The wetting of mineral surfaces by water and oil is described by models of surface forces that become important when two surfaces approach each other. Force components are electrostatic, van der Waals, and structural. The electrostatic forces depends on brine pH and salinity, crude oil composition, and the mineral. The surface forces are expressed as a disjoining pressure isotherm, and

G. J. Hirasaki

1991-01-01

266

Forced Model Equation for Turbulence  

Microsoft Academic Search

An artificial random force is introduced into Burgers' model equation for turbulence. This forced model equation is solved numerically as an initial-value problem. Both the driving force and initial velocity field are assumed Gaussian and are generated by a white noise process. Many statistical properties of this model for turbulence are studied. By adjusting the external force, the turbulence can

Dah-Teng Jeng

1969-01-01

267

Constructing force-closure grasps  

Microsoft Academic Search

This paper addresses the problem of synthesizing planar grasps that have force closure. A grasp on an object is a force closure grasp if and only if we can exert, through the set of contacts, arbitrary force and moment on this object. Equivalently, any motion of the object is resisted by a contact force, that is the object cannot break

Van-Duc Nguyen

1986-01-01

268

Internal networks for internal marketing  

Microsoft Academic Search

This paper is a report on a longitudinal case study of internal marketing as a relationship development process. The activity is observed and interpreted as a relationship development process in a large retail bank. Dominant modes emerge which are described as energising, code breaking and border crossing. These activities are seen to be facilitated by the sharing of knowledge through

David Ballantyne

1997-01-01

269

Forcing Pieris japonica ‘Debutante’  

Microsoft Academic Search

It was investigated whether Pieris japonica ‘Debutante’, cultivated as a potplant, can be forced before Christmas. To achieve this, early flower bud formation is required. Flower bud formation has an optimum temperature of approximately 17 °C. Short days, applied when the shoots have grown out sufficiently, promote flower bud formation. Young plants, potted in spring, form flower buds less readily

W. Sytsema; J. B. Ruesink

1996-01-01

270

Kelvin probe force microscopy  

Microsoft Academic Search

Measurements of the contact potential difference between different materials have been performed for the first time using scanning force microscopy. The instrument has a high resolution for both the contact potential difference (better than 0.1 mV) and the lateral dimension (<50 nm) and allows the simultaneous imaging of topography and contact potential difference. Images of gold, platinum, and palladium surfaces,

M. Nonnenmacher; M. P. O’Boyle; H. K. Wickramasinghe

1991-01-01

271

``Force,'' ontology, and language  

NASA Astrophysics Data System (ADS)

We introduce a linguistic framework through which one can interpret systematically students’ understanding of and reasoning about force and motion. Some researchers have suggested that students have robust misconceptions or alternative frameworks grounded in everyday experience. Others have pointed out the inconsistency of students’ responses and presented a phenomenological explanation for what is observed, namely, knowledge in pieces. We wish to present a view that builds on and unifies aspects of this prior research. Our argument is that many students’ difficulties with force and motion are primarily due to a combination of linguistic and ontological difficulties. It is possible that students are primarily engaged in trying to define and categorize the meaning of the term “force” as spoken about by physicists. We found that this process of negotiation of meaning is remarkably similar to that engaged in by physicists in history. In this paper we will describe a study of the historical record that reveals an analogous process of meaning negotiation, spanning multiple centuries. Using methods from cognitive linguistics and systemic functional grammar, we will present an analysis of the force and motion literature, focusing on prior studies with interview data. We will then discuss the implications of our findings for physics instruction.

Brookes, David T.; Etkina, Eugenia

2009-06-01

272

The fifth force  

SciTech Connect

We present a phenomenological description of the ''fifth force'' which focuses on the implications of the existing data from satellite and geophysical measurements of gravity, the Eoetvoes experiment, decays into hyperphotons, and the energy-dependence of the K/sup 0/ - anti K/sup 0/ parameters.

Fischbach, E.; Sudarsky, D.; Szafer, A.; Talmadge, C.; Aronson, S.H.

1986-01-01

273

UCLA Library Task Force  

ERIC Educational Resources Information Center

|The University of California at Los Angeles library is using part of its staff in a special mobile Task Force group to work on system-wide projects directed toward the elimination of backlogs and toward development of improved manual and automated systems. (Author)|

Nixon, Roberta

1974-01-01

274

Reduction in Force.  

ERIC Educational Resources Information Center

|Chapter 2 in a book on school law discusses the reasons for reduction in force (RIF) and presents a set of model regulations for school districts as the best means of minimizing legal problems resulting from RIF. The reasons for RIF include declining student enrollments; reduced turnover among teachers; changes in programs; and more constrained…

Phay, Robert

275

The ``Phantom'' Force  

Microsoft Academic Search

III. WHILE very clearly establishing that it is to the force urging a body that the potential energy which the body has not, but can have, must properly be assigned, and calling it very appropriately the ``energy of tension'',2 a very apposite remark (which I do not remember to have met with before) is added by ``X'' in his concluding

A. S. Herschel

1878-01-01

276

Use of Force (Video).  

National Technical Information Service (NTIS)

This video uses a dramatic recreation of an illegal but peaceful demonstration that gets out of hand to look at the different levels of provocation a police officer might encounter in his or her everyday job and the proper level of force that officers sho...

1993-01-01

277

Orbital Forces: Student Page  

NSDL National Science Digital Library

This activity teaches students about orbital motions and forces using a tennis ball swung by a ribbon. Students answer the question "What happens when you let the ball go?" Background information, activity procedures, and key words are provided. This activity is part of Exploring Planets in the Classroom's Planetary Properties series.

278

Non-gravitational Force  

Microsoft Academic Search

A force which is not gravitational in origin that acts on a celestial body to alter its orbit. The term is used in connection with comets, in which the outgassing of volatile material through vents leading to the surface of the nucleus can give rise to jets. Strong jets can behave as rockets and alter comets' orbits, in much the

P. Murdin

2000-01-01

279

The Dynamic Force Table  

ERIC Educational Resources Information Center

We examine an experimental apparatus that is used to motivate the connections between the basic properties of vectors, potential functions, systems of nonlinear equations, and Newton's method for nonlinear systems of equations. The apparatus is an adaptation of a force table where we remove the center-pin and allow the center-ring to move freely.…

Geddes, John B.; Black, Kelly

2008-01-01

280

Polarizable force fields  

Microsoft Academic Search

Standard force fields used in biomolecular computing describe electrostatic interactions in terms of fixed, usually atom-centered, charges. Real physical systems, however, polarize substantially when placed in a high-dielectric medium such as water — or even when a strongly charged system approaches a neutral body in the gas phase. Such polarization strongly affects the geometry and energetics of molecular recognition. First

Thomas A Halgren; Wolfgang Damm

2001-01-01

281

The Dynamic Force Table  

ERIC Educational Resources Information Center

|We examine an experimental apparatus that is used to motivate the connections between the basic properties of vectors, potential functions, systems of nonlinear equations, and Newton's method for nonlinear systems of equations. The apparatus is an adaptation of a force table where we remove the center-pin and allow the center-ring to move freely.…

Geddes, John B.; Black, Kelly

2008-01-01

282

Facilities Task Force.  

ERIC Educational Resources Information Center

|The Los Angeles Public School District is experiencing considerable overcrowding and deterioration of its public schools without adequate funding or planning to build new ones. This document presents the recommendations of a task force that assessed the district's public school crisis in the following areas: school maintenance; new facilities…

Los Angeles Unified School District, CA. School Reform Office.

283

Wetlands International  

NSDL National Science Digital Library

Established as a non-governmental organization, Wetlands International is concerned with promoting the conservation and wise use of wetlands on the global, regional, and national levels. Much of the information on the site is contained within a dozen or so sections along the left-hand side of the homepage. First-time visitors may want to read through the "About Us" area before proceeding to the "Introduction to Wetlands" area. Scholars and policy analysts will want to also look through the "Publications" area. Here they will find information sheets on peatland loss, user handbooks on various wetland regions, and related fact sheets for general use. Visitors may also want to peruse the "Biodiversity Programmes" area to learn more about the species and habitats that Wetlands International works to preserve through their advocacy work. The site is rounded out by a collection of recent news stories and press releases.

284

Internal Flow  

NASA Astrophysics Data System (ADS)

Focusing on phenomena important in implementing the performance of a broad range of fluid devices, this work describes the behavior of internal flows encountered in propulsion systems, fluid machinery (compressors, turbines, and pumps) and ducts (diffusers, nozzles and combustion chambers). The book equips students and practicing engineers with a range of new analytical tools. These tools offer enhanced interpretation and application of both experimental measurements and the computational procedures that characterize modern fluids engineering.

Greitzer, E. M.; Tan, C. S.; Graf, M. B.

2004-06-01

285

Probing cellular traction forces with magnetic nanowires and microfabricated force sensor arrays  

NASA Astrophysics Data System (ADS)

In this paper, the use of magnetic nanowires for the study of cellular response to force is demonstrated. High-aspect ratio Ni rods with diameter 300 nm and lengths up to 20 ?m were bound to or internalized by pulmonary artery smooth muscle cells (SMCs) cultured on arrays of flexible micropost force sensors. Forces and torques were applied to the cells by driving the nanowires with AC magnetic fields in the frequency range 0.1-10 Hz, and the changes in cellular contractile forces were recorded with the microposts. These local stimulations yield global force reinforcement of the cells’ traction forces, but this contractile reinforcement can be effectively suppressed upon addition of a calcium channel blocker, ruthenium red, suggesting the role of calcium channels in the mechanical response. The responsiveness of the SMCs to actuation depends on the frequency of the applied stimulation. These results show that the combination of magnetic nanoparticles and micropatterned, flexible substrates can provide new approaches to the study of cellular mechanotransduction.

Lin, Yi-Chia; Kramer, Corinne M.; Chen, Christopher S.; Reich, Daniel H.

2012-02-01

286

Investigation of Calibrating Force Transducer Using Sinusoidal Force  

SciTech Connect

Sinusoidal force calibration method was studied several years before at Physikalisch-Technische Bundesanstalt (PTB). A similar dynamic force calibration system is developed at Changcheng Institute of Metrology and Measurement (CIMM). It uses electro-dynamic shakers to generate dynamic force in the range from 1 N to 20 kN, and heterodyne laser interferometers are used for acceleration measurement. The force transducer to be calibrated is mounted on the shaker, and a mass block is screwed on the top of force transducer, the sinusoidal forces realized by accelerated load masses are traceable to acceleration and mass according to the force definition. The methods of determining Spatial-dependent acceleration on mass block and measuring the end mass of force transducer in dynamic force calibration are discussed in this paper.

Zhang Li [School of Instrumentation Science and Opto-electronics Engineering, Beihang University, Beijing (China); Key Laboratory for Metrology, Changcheng Institute of Metrology and Measurement (CIMM), Beijing 100095 (China); Wang Yu; Zhang Lizhe [Key Laboratory for Metrology, Changcheng Institute of Metrology and Measurement (CIMM), Beijing 100095 (China)

2010-05-28

287

Expanding the role of internal facility assessments  

SciTech Connect

The US Air Force (USAF) Environmental Compliance Assessment and Management Program (ECAMP) is an effective and comprehensive system to evaluate environmental compliance at individual USAF installations. The ECAMP assessment is typically performed by a team of experts from the installation`s Major Command (MAJCOM) Headquarters, and is often augmented with technical contractor support. As directed by Air Force policy, an external ECAMP assessment is required at a minimum of every three years for each installation. In the intervening years, each installation is required to perform an internal ECAMP assessment, with its own personnel and resources. Even though team composition differs, the internal and external ECAMP assessments are likely to be very similar in scope, objectives, and deliverables. For over nine years, Argonne National Laboratory (ANL) has supported several Air Force MAJCOMs in performing their external ECAMP assessments. More recently, ANL has also had the opportunity to provide technical support and training at individual installations during their preparation and conduct of internal ECAMP assessments. From that experience, the authors have learned that the quality and value of the internal assessment is enhanced by making it a vehicle for training, planning, and interaction among organizations. Various strategies and techniques have been successfully employed to derive maximum benefit and insight from the internal assessment process. Experiences that involve expanding the scope and objectives of internal assessments to meet specific goals are presented. The expansion of scope and objectives include preassessment training, planning, and evaluator interactions as part of the overall internal assessment process.

Kolpa, R.L.; Levenson, J.B. [Argonne National Lab., IL (United States); Weaver, M.A. [Headquarters Air Force Materiel Command, Wright-Patterson AFB, OH (United States)

1996-05-01

288

Coronal mass ejections as expanding force-free spheromaks  

NASA Astrophysics Data System (ADS)

We discuss self-similar dynamics of an expanding, spherical force-fee magnetic configuration as a model of CMEs. While keeping the internal magnetic structure of a stationary sphero-mak, the expansion leads to complicated internal velocities and rotation, induced by inductive electric fields. The field remains force-free at every moment. We compare the models with measurements of magnetic fields in CMEs by heliocentric spacecrafts. Expansion may also induce electric fields parallel to magnetic fields and lead to resistive dis-sipation with highly anomalous resistivity; this may explain additional heating of Solar CMEs inferred from observations of ion charge states

Lyutikov, Maxim

289

Physical curl forces: dipole dynamics near optical vortices  

NASA Astrophysics Data System (ADS)

The force on a particle with complex electric polarizability is known to be not derivable from a potential, so its curl is non-zero. This ‘curl force’ is studied in detail for motion near an anisotropic optical vortex of arbitrary strength. Fundamental questions are raised by the fact that although the curl force requires the polarizability to have a non-zero imaginary part, reflecting absorption or scattering (‘dissipation’) in the internal dipole dynamics, the particle motion that it generates is non-dissipative (volume-preserving in the position-velocity state space).

Berry, M. V.; Shukla, Pragya

2013-10-01

290

Drag force scaling for penetration into granular media  

NASA Astrophysics Data System (ADS)

Impact dynamics is measured for spherical and cylindrical projectiles of many different densities dropped onto a variety non-cohesive granular media. The results are analyzed in terms of the material-dependent scaling of the inertial and frictional drag contributions to the total stopping force. The inertial drag force scales similar to that in fluids, except that it depends on the internal friction coefficient. The frictional drag force scales as the square-root of the density of granular medium and projectile, and hence cannot be explained by the combination of granular hydrostatic pressure and Coulomb friction law. The combined results provide an explanation for the previously observed penetration depth scaling.

Katsuragi, Hiroaki; Durian, Douglas J.

2013-05-01

291

Muscular forces exerted on the normal deciduous dentition.  

PubMed

This study evaluated the distributing characteristic of the forces exerting on the normal deciduous dentition and the relationship between the muscular forces, sex, and oral function. The pressure measurements were made with a computer-aided perioral force-measuring system designed by the authors. The forces were measured when the subject's head position was in a state of natural head position and oral function was at rest or with swallowing. The results indicated that the forces from lips, cheeks, and tongue at rest were about 37-208 N/m2, whereas the pressure during swallowing was about 1009-1679 N/m2. At rest, the pressure from lips and cheeks was higher than that from tongue (P < .05), whereas during swallowing, the lingual pressure was statistically larger (P < .001). A significant correlation existed between the muscular pressure and sex. When at rest, the boy's force from cheeks was higher than that of the girl's (P < .05) but during swallowing the boy's labial pressure was statistically higher than that of the girl's (P < .01). It was concluded that (1) the deciduous teeth are not in a state of absolute balance between external and internal forces, (2) the distributing manner and unbalanced mode of the forces are different with the different oral functions, (3) the lingual side of the mandibular anterior teeth endures great differences during oral functions and it may account for high incidence of malocclusion in this segment, and (4) a statistical difference between muscular forces and sex exists. PMID:16279824

Ruan, Wen-hua; Chen, Min-dong; Gu, Zhi-yuan; Lu, Yuan; Su, Ji-mei; Guo, Qi

2005-09-01

292

Force Modulator System  

SciTech Connect

Many metal parts manufacturers use large metal presses to shape sheet metal into finished products like car body parts, jet wing and fuselage surfaces, etc. These metal presses take sheet metal and - with enormous force - reshape the metal into a fully formed part in a manner of seconds. Although highly efficient, the forces involved in forming metal parts also damage the press itself, limit the metals used in part production, slow press operations and, when not properly controlled, cause the manufacture of large volumes of defective metal parts. To date, the metal-forming industry has not been able to develop a metal-holding technology that allows full control of press forces during the part forming process. This is of particular importance in the automotive lightweighting efforts under way in the US automotive manufacturing marketplace. Metalforming Controls Technology Inc. (MC2) has developed a patented press control system called the Force Modulator that has the ability to control these press forces, allowing a breakthrough in stamping process control. The technology includes a series of hydraulic cylinders that provide controlled tonnage at all points in the forming process. At the same time, the unique cylinder design allows for the generation of very high levels of clamping forces (very high tonnages) in very small spaces; a requirement for forming medium and large panels out of HSS and AHSS. Successful production application of these systems testing at multiple stamping operations - including Ford and Chrysler - has validated the capabilities and economic benefits of the system. Although this technology has been adopted in a number of stamping operations, one of the primary barriers to faster adoption and application of this technology in HSS projects is system cost. The cost issue has surfaced because the systems currently in use are built for each individual die as a custom application, thus driving higher tooling costs. This project proposed to better marry the die-specific Force Modulator technology with stamping presses in the form of a press cushion. This system would be designed to operate the binder ring for multiple parts, thus cutting the per-die cost of the technology. This study reports the results of technology field application. This project produced the following conclusions: (1) The Force Modulator system is capable of operating at very high tempos in the stamping environment; (2) The company can generate substantial, controlled holding tonnage (binder ring pressure) necessary to hold high strength steel parts for proper formation during draw operations; (3) A single system can be designed to operate with a family of parts, thus significantly reducing the per-die cost of a FM system; (4) High strength steel parts made with these systems appear to show significant quality improvements; (5) The amounts of steel required to make these parts is typically less than the amounts required with traditional blank-holding technologies; and (6) This technology will aid in the use of higher strength steels in auto and truck production, thus reducing weight and improving fuel efficiency.

Redmond Clark

2009-04-30

293

Tracking the Coriolis Force  

NSDL National Science Digital Library

Tracking the Coriolis Force uses the Tracker video analysis tool to model the motion of a ball rolling with constant velocity on a rotating merry-go-round. Video includes the motion of the ball as viewed from the rotating reference frame of the merry-go-round. Using the Coriolis force equation, students build a model of the motion. The zip file contains the activity handout, video and Tracker file. The video comes from YouTube and can be found at http://www.youtube.com/watch?v=LAX3ALdienQ. A talk about this activity from the AAPT Winter Meeting 2013 can be found at http://tinyurl.com/trackerCoriolis. To open the Tracker file, download and run Tracker from http://www.cabrillo.edu/~dbrown/tracker/. Tracker is free.

Cox, Anne

2012-06-16

294

Projectiles and aerodynamic forces  

NASA Astrophysics Data System (ADS)

Most elementary works on physics contain something about the motion of projectiles which, it is commonly assumed, are acted on only by gravity. Yet even on balls used in various games the aerodynamic forces are rarely completely negligible (Daish 1972, especially chs 6 and 12). As for bullets and artillery projectiles, the force of air resistance on them is commonly many times that of gravity (Smith 1962). What purpose, then, is supposed to be served by presenting students with such unphysical notions and asking them to spend time working out conundrums about such matters? Warren (1965) has commented on the lack of realism in many parts of school physics, but does not seem to have said much about this example. The author's purpose is to find simple ways of taking into account the air resistance on projectiles, at least approximately.

Armstrong, H. L.

1984-09-01

295

Atomic Force Acoustic Microscopy  

NASA Astrophysics Data System (ADS)

This chapter shortly reviews the scientific background of Atomic Force Acoustic Microscopy (AFAM), the basic theoretical models, the experimental techniques to obtain quantitative values of local elastic constants, and non-linear AFAM. Analytical and finite element models describing transverse flexural vibrations of AFM cantilevers with and without tip-surface contact are recapitulated. The models are suitable for micro fabricated silicon cantilevers of approximately rectangular cross section which are typically used in AFAM. Experimental methods to obtain single-point as well as array measurements and full spectroscopy images are discussed in combination with the respective reference methods for calibration. In a non-linear AFAM experiment, the vibration amplitudes of the sample surface and the cantilever are measured quantitatively with an interferometer at different excitation amplitudes, and the full tip-sample interaction force curve is reconstructed using a frequency dependent transfer function.

Rabe, U.; Kopycinska-Müller, M.; Hirsekorn, S.

296

Suicide and Forced Marriage  

PubMed Central

Background: The prevailing view that the vast majority of those who complete suicide have an underlying psychiatric disorder has been recently challenged by research on the contribution of “predicaments”, in the absence of mental illness, to suicide. In this paper, we sought data to support the notion that forced marriage may lead to suicide without the presence of psychiatric disorder. Methods: Historical records, newspapers, and the electronic media were searched for examples. Results: Two examples from ancient times and six from the last hundred years were located and described. Conclusion: These cases suggest that forced marriage may lead to suicide and complements earlier findings that loss of fortune, health, liberty, and reputation may lead to suicide in the absence of mental disorder.

Pridmore, Saxby; Walter, Garry

2013-01-01

297

Exploring Forces: Static Electricity  

NSDL National Science Digital Library

In this activity, learners investigate what happens when you build up static electricity on plastic balls. Learners discover that electrostatic forces cause smaller balls to suspend in a tube, while larger balls fall to the bottom. This activity shows learners that size can affect the way a material behaves. This activity is a great way to talk about how different things behave at the nanoscale.

Network, Nanoscale I.; Sciencenter

2010-01-01

298

Atomic Force Microscopy  

NSDL National Science Digital Library

This website contains a series of videos describing the operation of Atomic Force Microscopes. These videos include outlines of microscopy, models of AFM's, and examples of the operation and output of real microscopes. Also included are student activities and curricular resources for teachers. This is one of a series of similar modules on Nanotechnology produced by the University of Massachusetts Amherst Center on Hierarchical Manufacturing.

2013-02-20

299

Intermolecular Forces in Liquids  

Microsoft Academic Search

The volume energy of liquids, Ev, is formulated, as in the Born and Landé theory of the lattice energy of crystals, in terms of attractive and repulsive forces varying with inverse powers of the distance, or volume, giving Ev=-aVm1-nmV0Vn- m, where m and n are, respectively, the exponents of attraction and repulsion, a the attraction constant and V the volume

Joel H. Hildebrand

1929-01-01

300

Uplifting Force: Buoyancy & Density  

NSDL National Science Digital Library

In this investigation, learners explore the force known as buoyancy by placing various objects into water and observing how they behave (for example, which sink more quickly, which float, how much water they displace and how air plays a role in keeping objects afloat). The introduction to the lesson tells the story of Archimedes, the Greek mathematician, who first discovered the law of buoyancy while attempting to determine the mass of a crown of gold.

Jersey, New; Center, Liberty S.; Coalition, New J.

2006-01-01

301

Dynamic Force Microscopy  

Microsoft Academic Search

This chapter presents an introduction to the concept of the dynamic operational mode of the atomic force microscope (dynamic\\u000a AFM). While the static, or contact mode AFM is a widespread technique to obtain nanometer resolution images on a wide variety\\u000a of surfaces, true atomic resolution imaging is routinely observed only in the dynamic mode. We will explain the jump-to-contact\\u000a phenomenon

André Schirmeisen; Boris Anczykowski; Harald Fuchs

302

On Dual Configurational Forces  

Microsoft Academic Search

The dual conservation laws of elasticity are systematically re-examined by using both Noether's variational approach and Coleman–Noll–Gurtin's thermodynamics approach. These dual conservation laws can be interpreted as the dual configurational force, and therefore they provide the dual energy–momentum tensor. Some previously unknown and yet interesting results in elasticity theory have been discovered. As an example, we note the following duality

Shaofan Li; Anurag Gupta

2006-01-01

303

Modified entropic force  

SciTech Connect

The theory of statistical thermodynamics tells us the equipartition law of energy does not hold in the limit of very low temperatures. It is found the Debye model is very successful in explaining the experimental results for most of the solid objects. Motivated by this fact, we modify the entropic force formula which is proposed very recently. Since the Unruh temperature is proportional to the strength of the gravitational field, so the modified entropic force formula is an extension of the Newtonian gravity to the weak field. On the contrary, general relativity extends Newtonian gravity to the strong field case. Corresponding to Debye temperature, there exists a Debye acceleration g{sub D}. It is found the Debye acceleration is g{sub D}=10{sup -15} N kg{sup -1}. This acceleration is very much smaller than the gravitational acceleration 10{sup -4} N kg{sup -1} which is felt by Neptune and the gravitational acceleration 10{sup -10} N kg{sup -1} felt by the Sun. Therefore, the modified entropic force can be very well approximated by the Newtonian gravity in the Solar System and in the Galaxy. With this Debye acceleration, we find the current cosmic speeding up can be explained without invoking any kind of dark energy.

Gao Changjun [National Astronomical Observatories, Chinese Academy of Sciences, Key Laboratory of Optical Astronomy, NAOC, CAS, Beijing, 100012 and Kavli Institute for Theoretical Physics China, CAS, Beijing 100190 (China)

2010-04-15

304

Surrogate forces and Soviet foreign policy  

SciTech Connect

This study examines the Soviet use of client actors in a surrogate capacity in the Third World. Although the employment of military proxies is certainly not a new phenomenon in international affairs, the level and scope of the Soviet use of surrogate forces is without recent precedent. Soviet clients and associated actors have supported terrorist organizations, guerrilla movements, and legitimate governments. In doing so, they have been employed as arms suppliers, training and advisory personnel, in specialized combat roles such as air defense, demolitions and communications and, most boldly, as independent field forces in conventional operations. The Soviet Union's level of effort in this area over time indicates that the employment of military proxies has become an integral aspect of its foreign policy. This is particularly true of Soviet policy toward the developing world where for reasons of access, attribution, and simple economics the use of proxy assets has provided Moscow with an unusually attractive means of indirect local intervention.

McCormick, G.H.

1986-01-01

305

Quantification of bacterial adhesion forces using atomic force microscopy (AFM)  

Microsoft Academic Search

This study demonstrated that atomic force microscopy (AFM) can be used to obtain high-resolution topographical images of bacteria, and to quantify the tip–cell interaction force and the surface elasticity. Results show that the adhesion force between the Si3N4 tip and the bacteria surface was in the range from ?3.9 to ?4.3 nN. On the other hand, the adhesion forces at

Herbert H. P. Fang; Kwong-Yu Chan; Li-Chong Xu

2000-01-01

306

Trafficking in Persons: The U.S. and International Response (Updated June 24, 2005).  

National Technical Information Service (NTIS)

Trafficking in people for prostitution and forced labor is one of the most prolific areas of international criminal activity and is of significant concern to the United States and the international community. The overwhelming majority of those trafficked ...

F. T. Miko

2005-01-01

307

Generalized Electrodynamics With Ternary Internal Structure  

Microsoft Academic Search

.  In Refs. [2]–[7] we suggested generalized dynamic equations of motion of relativistic charged particles inside electromagnetic\\u000a fields. The dynamic equations had been formulated in terms of external as well as internal momenta. Evolution equations for\\u000a external momenta, the Lorentz-force equations, had been derived from evolution equations for internal momenta. In this paper,\\u000a along with relativistic dynamics we generalize electromagnetic fields

Robert M. Yamaleev

2006-01-01

308

Final report on force key comparison CCM.F-K4.a and CCM.F-K4.b for 4 MN and 2 MN forces  

Microsoft Academic Search

This report gives the results for the Comit International des Poids et Mesures (CIPM) key comparisons in force, designated by comparison numbers CCM.F-K4.a and CCM.F-K4.b, for the maximum force values of 4 MN and 2 MN, respectively. Eight National Metrology Institutes, employing nine national force standard machines, participated in these comparisons. The National Institute of Standards and Technology (NIST) served

T W Bartel

2012-01-01

309

Unsteady Force and Pressure Measurements.  

National Technical Information Service (NTIS)

Various aspects of the general problem of unsteady pressure and force measurement are described, and a number of examples of solutions to various force- and pressure-measurement problems are outlined. The examples are intended to illustrate the applicatio...

W. W. Willmarth

1971-01-01

310

Understanding Forces: What's the Problem?  

ERIC Educational Resources Information Center

|Misconceptions about forces are very common and seem to arise from everyday experience and use of words. Ways to improve students' understanding of forces, as used in recent a IOP CD-Rom, are discussed here.|

Kibble, Bob

2006-01-01

311

Lorentz Force Control of Turbulence.  

National Technical Information Service (NTIS)

Lorentz Force actuators were developed and characterized. They were used to measure the effect of lorentz force control on the drag of a fully turbulent channel flow. Approximately 15% drag reduction was achieved.

K. Breuer

2005-01-01

312

Internal Stress Field and Elastic Moduli of Fibrous Compositions.  

National Technical Information Service (NTIS)

In order to simplify analysis of the internal stress field the general solution of the problem is divided into partial solutions, which correspond to the applied components of the external force field. The solutions in this article are, Longitudinal Shear...

V. F. Fy

1972-01-01

313

Column internals  

SciTech Connect

In the fields of distillation, absorption, stripping and extraction, theory and technology go hand in hand. The thermodynamic principles of phase equilibrium and the concepts of mass transfer and fluid flow are of primary importance in all of these operations. The engineer must understand these phenomena to select equipment effectively. This article discusses the latest in commercial technology in column internals for gas-liquid and liquid-liquid contacting. The principles of operation are explained vis-a-vis the characteristics of the applications in which they are used. The focus is on moderate-to-large columns for refining and chemical applications. Guidelines for selecting the most appropriate type of device are presented, and examples of typical applications are described.

Bravo, J.L. [Shell Oil Co., Houston, TX (United States)

1998-02-01

314

International Rivers  

NSDL National Science Digital Library

International Rivers is an organization that opposes the construction of destructive dams on rivers, and they also support communities affected by dams. Their aim is to "protect rivers and promote just and sustainable water and energy development." Visitors will find most of their questions about dams and hydroelectricity can be answered under the "Learn More" tab's FAQ section. Along with each answer, there is most often an article, slideshow, video or other resource to explore further. Some of the pieces examine why there is opposition to large dams, the expense of hydroelectricity, the lack of local jobs produced when a dam is being built in a developing country, and the number of people displaced by dams. Under the "Get Involved" tab, there is a section called "Tools for Educators" that include lessons for introductory learners, intermediate learners, advanced learners, and a "River Educator's Toolkit", which contains lessons on the four major rivers in Asia, Africa, and South America.

315

Lateral Casimir Force beyond the Proximity-Force Approximation  

SciTech Connect

We argue that the appropriate variable to study a nontrivial geometry dependence of the Casimir force is the lateral component of the Casimir force, which we evaluate between two corrugated metallic plates outside the validity of the proximity-force approximation. The metallic plates are described by the plasma model, with arbitrary values for the plasma wavelength, the plate separation, and the corrugation period, the corrugation amplitude remaining the smallest length scale. Our analysis shows that in realistic experimental situations the proximity-force approximation overestimates the force by up to 30%.

Rodrigues, Robson B.; Neto, Paulo A. Maia [Instituto de Fisica, UFRJ, CP 68528, Rio de Janeiro, RJ, 21941-972 (Brazil); Lambrecht, Astrid; Reynaud, Serge [Laboratoire Kastler Brossel, CNRS, ENS, Universite Pierre et Marie Curie case 74, Campus Jussieu, F-75252 Paris Cedex 05 (France)

2006-03-17

316

In vivo forces generated by finger flexor muscles do not depend on the rate of fingertip loading during an isometric task  

Microsoft Academic Search

Risk factors for activity-related tendon disorders of the hand include applied force, duration, and rate of loading. Understanding the relationship between external loading conditions and internal tendon forces can elucidate their role in injury and rehabilitation. The goal of this investigation is to determine whether the rate of force applied at the fingertip affects in vivo forces in the flexor

Katarzyna Kursa; Edward Diao; Lisa Lattanza; David Rempel

317

Vibrational spectrum and force field of dimethyldimethoxysilane  

SciTech Connect

Experimental data is presented on the spectra of (CH/sub 3/)/sub 2/Si(OCH/sub 3/)/sub 2/ (I), (CH/sub 3/)/sub 2/Si(OCD/sub 3/)/sub 2/ (II), and (CD/sub 3/)/sub 2/Si(OCH/sub 3/)/sub 2/ (III). The results of the determination of the force constants on the basis of the optimization of the solution of the inverse mechanical problem of the theory of molecular vibrations with consideration of all the internal degrees of freedom with the exception of the coordinates corresponding to internal rotations are discussed. Raman spectra of I, II, and III in the liquid phase is shown and the IR spectra of amorphous films of I, II, and III are illustrated.

Tenisheva, T.F.; Lazarev, A.N.

1986-01-01

318

Low temperature friction force microscopy  

Microsoft Academic Search

The application of friction force techniques within atomic force microscopy (AFM) allows for direct measurements of friction forces at a sliding, single-asperity interface. The temperature dependence of such single-asperity contacts provides key insight into the comparative importance of dissipative mechanisms that result in dry sliding friction. A variable temperature (VT), ultrahigh vacuum (UHV) AFM was used with an interface consisting

Christopher Gregory Dunckle

2010-01-01

319

Forcing Axioms and Cardinal Arithmetic  

Microsoft Academic Search

We survey some recent results on the impact of strong forcing axioms such as the Proper Forcing Axiom PFA and Martin's Maximum MM on cardinal arithmetic. We concentrate on three combinatorial principles which follow from strong forcing axioms: stationary set reection, Moore's Mapping Reection Principle MRP and the P-ideal dichotomy introduced by Abraham and Todor cevi c which play the

Boban Veli

320

Air Force satellite position management  

Microsoft Academic Search

The Space Act of 1958 identified the Department of Defense as responsible for conducting military operations in space. Subsequently, the United States Air Force was assigned to act as the DOD's executive agent for space. In addition, the Air Force is responsible for acquisition and launch of DOD space systems. Within the Air Force, space related roles and activities have

R. Davis

1985-01-01

321

Constructing Force-Closure Grasps  

Microsoft Academic Search

This paper presents fast and simple algorithms for directly constructing force-closure grasps based on the shape of the grasped object. The synthesis of force-closure grasps finds in dependent regions of contact for the fingertips, such that the motion of the grasped object is totally constrained. A force- closure grasp implies equilibrium grasps exist. In the reverse direction, we show that

Van-duc Nguyen

1988-01-01

322

Future Air Force Tactical Communications  

Microsoft Academic Search

During the 1980's, many improvements will be made in the Air Force's ability to communicate in a battlefield environment. Programs like JTIDS, SEEK TALK, TRI-TAC, and the Ground Mobile Forces satellite communications terminals will improve the security, jam resistance, connectivity, and capacity of today's Air Force tactical communications. Even after these programs have been implemented, however, some important problem areas

D. Brick; F. Ellersick

1980-01-01

323

Stem Cell Task Force  

NSDL National Science Digital Library

This Web site from the National Institutes of Health (NIH) provides an overview of the activities of an NIH task force established to move the stem cell research agenda forward. The section titled Scientific Research may be of particular interest to researchers in this area. It provides links to the Web sites of stem cell-related research at a number of NIH institutes, as well as an extensive information index, a FAQs page about stem cell research, information on funding opportunities, and much more.

324

Causal Entropic Forces  

NASA Astrophysics Data System (ADS)

Recent advances in fields ranging from cosmology to computer science have hinted at a possible deep connection between intelligence and entropy maximization, but no formal physical relationship between them has yet been established. Here, we explicitly propose a first step toward such a relationship in the form of a causal generalization of entropic forces that we find can cause two defining behaviors of the human “cognitive niche”—tool use and social cooperation—to spontaneously emerge in simple physical systems. Our results suggest a potentially general thermodynamic model of adaptive behavior as a nonequilibrium process in open systems.

Wissner-Gross, A. D.; Freer, C. E.

2013-04-01

325

International vision and strategy for drug regulatory authority: the PMDA's international vision.  

PubMed

The past several years saw various countries' drug regulatory authorities (DRAs) internationalizing their activities in response to the rapid globalization of pharmaceutical affairs. This is the second surge of internationalization, coming after the first in the 1990s, when the International Conference on Harmonisation (ICH) and the Global Harmonization Task Force were founded. For maximum effect, a DRA needs to carefully strategize its international activities. The significance of international master plans is discussed in relation to the recently published International Vision of Japan's Pharmaceuticals and Medical Devices Agency (PMDA). PMID:22871996

Tominaga, Toshiyoshi; Ando, Yuki; Kondo, Tatsuya

2012-08-08

326

Air Force Technology  

NSDL National Science Digital Library

Although designed for professional contractors, this site offers an interesting diversion for the technophile or armchair general. Provided by Net Resources International, the site contains a host of professional information, including industry organizations, exhibitions, and conferences, and a company index. However, general users will be most interested in the current projects and equipment catalog sections, which offer specifications and photos of a large number of interesting gadgets and vehicles.

327

Force threshold for hearing by direct bone conduction.  

PubMed

The bone-anchored hearing aid is connected, by means of a skin-penetrating bayonet coupling, to an implanted titanium fixture. Hence, direct bone conduction (dbc) excitation is used. Since no international standard of audiometric zero for dbc force threshold exists, it is of general interest to determine the dbc force threshold for normal hearing subjects. Two different methods have previously been applied to estimate the relation between bone conduction (bc) and dbc thresholds. One preliminary problem was to make a measurement of the output-force level of dbc transducers, which is equivalent to the situation in situ. A skull simulator, TU-1000, has been designed for measuring the output-force level of dbc transducers. The skull simulator does, in an adequate way, reflect the mechanical point impedance of the human skull. This opportunity to determine equivalent dbc force thresholds has motivated the present study in which a linear relation between the dbc force threshold and the bc force threshold was estimated. The estimate found in the present study conforms fairly well with the two previously found estimates. It is suggested that the estimate found in the present study be used as the reference equivalent threshold force level for dbc. PMID:7876434

Carlsson, P; Håkansson, B; Ringdahl, A

1995-02-01

328

Force control for mechanoinduction of impedance variation in cellular organisms  

NASA Astrophysics Data System (ADS)

Constantly exposed to various forms of mechanical forces inherent in their physical environment (such as gravity, stress induced by fluid flow or cell-cell interactions, etc), cellular organisms sense such forces and convert them into biochemical signals through the processes of mechanosensing and mechanotransduction that eventually lead to biological changes. The effect of external forces on the internal structures and activities in a cellular organism may manifest in changes its physical properties, such as impedance. Studying variation in the impedance of a cellular organism induced by the application of an external mechanical force represents a meaningful endeavor (from a biosystems perspective) in exploring the complex mechanosensing and mechanotransduction mechanisms that govern the behavior of a cellular organism under the influence of external mechanical stimuli. In this paper we describe the development of an explicit force-feedback control system for exerting an indentation force on a cellular organism while simultaneously measuring its impedance. To demonstrate the effectiveness of this force-control system, we have conducted experiments using zebrafish embryos as a test model of a cellular organism. We report experimental results demonstrating that the application of a properly controlled external force leads to a significant change in the impedance of a zebrafish embryo. These results offer support for a plausible explanation that activities of pore canals in the chorion are responsible for the observed change in impedance.

Hoo Nam, Joo; Chen, Peter C. Y.; Lu, Zhe; Luo, Hong; Ge, Ruowen; Lin, Wei

2010-02-01

329

Bone contact forces on the distal tibia during the stance phase of running.  

PubMed

Although the tibia is a common site of stress fractures in runners, the loading of the tibia during running is not well understood. An integrated experimental and modeling approach was therefore used to estimate the bone contact forces acting on the distal end of the tibia during the stance phase of running, and the contributions of external and internal sources to these forces. Motion capture and force plate data were recorded for 10 male runners as they ran at 3.5-4 m/s. From these data, the joint reaction force (JRF), muscle forces, and bone contact force on the tibia were computed at the ankle using inverse dynamics and optimization methods. The distal end of the tibia was compressed and sheared posteriorly throughout most of stance, with respective peak forces of 9.00+/-1.13 and 0.57+/-0.18 body weights occurring during mid stance. Internal muscle forces were the primary source of tibial compression, whereas the JRF was the primary source of tibial shear due to the forward inclination of the leg relative to the external ground reaction force. The muscle forces and JRF both acted to compress the tibia, but induced tibial shear forces in opposing directions during stance, magnifying tibial compression and reducing tibial shear. The superposition of the peak compressive and posterior shear forces at mid stance may contribute to stress fractures in the posterior face of the tibia. The implications are that changes in running technique could potentially reduce stress fracture risk. PMID:17662295

Sasimontonkul, Siriporn; Bay, Brian K; Pavol, Michael J

2007-07-26

330

Geographic Information Quality Management and Standardization in Finnish Defence Forces  

Microsoft Academic Search

SUMMARY The main issue in Geographic Information Quality Management (GIQM) and standardization is to achieve interoperability through standardization. This still ongoing research project defines a quality model for geographic information in Finnish Defence Forces (FDF). The quality model is strongly based on international ISO standardization. The quality model defines a basis for consistent concepts and methods for GIQM. FDF quality

Kari INGBERG

331

Possible Futures: Space Capability Risks and the Joint Force.  

National Technical Information Service (NTIS)

By the mid 2020s, near peer competitors, regional powers and international non-state actors will be able to threaten the Joint Force's access to and application of space-based capabilities. These threats will cover the spectrum of space operations, from o...

G. B. LaVezzi

2010-01-01

332

Forced and coerced sterilization of women in Europe  

Microsoft Academic Search

Human rights provisions in laws set by international treaties and national legislatures make individuals’ informed and freely given consent a precondition to the legality of their sterilization. Nevertheless, evidence shows that sterilizations have been undertaken by forceful means or coerced acceptance, to which women do not genuinely consent. The women are often members of ethnic minorities in their countries, such

Christina Zampas; Adriana Lama?ková

2011-01-01

333

Radiative forcings and global warming potentials of 39 greenhouse gases  

Microsoft Academic Search

The radiative forcings and global warming potentials for 39 greenhouse gases are evaluated using narrowband and broadband radiative transfer models. Unlike many previous studies, latitudinal and seasonal variations are considered explicitly, using distributions of major greenhouse gases from a combination of chemical-transport model results and Upper Atmosphere Research Satellite (UARS) measurements and cloud statistics from the International Satellite Cloud Climatology

Atul K. Jain; Bruce P. Briegleb; K. Minschwaner; Donald J. Wuebbles

2000-01-01

334

Analysis of Wind Forces on RoofTop Solar Panel  

Microsoft Academic Search

Structural loads on solar panels include forces due to high wind, gravity, thermal expansion, and earthquakes. International Building Code (IBC) and the American Society of Civil Engineers are two commonly used approaches in solar industries to address wind loads. Minimum Design Loads for Buildings and Other Structures (ASCE 7-02) can be used to calculate wind uplift loads on roof-mounted solar

Yogendra Panta; Ganesh Kudav

2011-01-01

335

California's Teaching Force: Key Issues and Trends, 2008  

ERIC Educational Resources Information Center

|For each of the past 10 years, the Center for the Future of Teaching and Learning has issued a report on the status of California's teaching force based on research conducted by SRI International. The Center provides practical information to help policymakers and education leaders understand the challenges they face is provided. Context, clarity…

Plattner, Andy

2008-01-01

336

75 FR 11512 - Consultative Group to Eliminate the Use of Child Labor and Forced Labor in Imported Agricultural...  

Federal Register 2010, 2011, 2012, 2013

...Group to Eliminate the Use of Child Labor and Forced Labor in Imported...with the use of forced labor or child labor. Recommendations developed...with expertise on international child labor and forced labor issues...March 22, 2010. No electronic media coverage will be allowed....

2010-03-11

337

Environmental Crack Driving Force  

NASA Astrophysics Data System (ADS)

The effect of environment on the crack driving force is considered, first by assuming quasistatic extension of a stationary crack and second, by use of stress corrosion cracking (SCC) crack growth rate models developed previously by this author and developed further here. A quasistatic thermodynamic energy balance approach, of the Griffith-Irwin type, is used to develop stationary crack threshold expressions, tilde{J}_c , which represent the conjoint mechanical and electrochemical conditions, below which stationary cracks are stable. Expressions for the electrochemical crack driving force (CDF) were derived using an analysis that is analogous to that used by Irwin to derive his "strain energy release rate," G, which Rice showed as being equivalent to his mechanical CDF, J. The derivations show that electrochemical CDFs both for active path dissolution (APD) and hydrogen embrittlement (HE) mechanisms of SCC are simply proportional to Tafel's electrochemical anodic and cathodic overpotentials, ? a and ? c, respectively. Phenomenological SCC models based on the kinetics of APD and HE crack growth are used to derive expressions for the kinetic threshold, J scc, below which crack growth cannot be sustained. These models show how independent mechanical and environmental CDFs may act together to drive SCC crack advance. Development of a user-friendly computational tool for calculating Tafel's overpotentials is advocated.

Hall, M. M.

2013-03-01

338

The Force of Friction  

NSDL National Science Digital Library

In the first of two lessons of this curricular unit, students are introduced to the concept of friction as a force that impedes motion when two surfaces are in contact. They work in teams to use a spring scale to drag an object such as a ceramic coffee cup along a table top or the floor; the spring scale allows them to measure the frictional force that exists between the moving cup and the surface it slides on. By modifying the bottom surface of the cup, students find out what kinds of surfaces generate more or less friction. They also discover that both static and kinetic friction are involved when an object initially at rest is caused to slide across a surface. In the second lesson of the unit, students design and conduct experiments to determine the effects of weight and surface area on friction. They discover that weight affects normal friction (the friction that results from surface roughness), but for very smooth surfaces, the friction due to molecular attraction is affected by contact area.

Engineering K-Ph.d. Program

339

Victor's Justice or the Law? Judging And Punishing At The International Criminal Tribunal For The Former Yugoslavia  

Microsoft Academic Search

The development of fair and impartial criteria for judging those accused of international crimes is one of the most critical issues facing the international community and the International Criminal Tribunal for the Former Yugoslavia (ICTY). Are the resources, experience, and moral force so weighted in favor of the international community that the accused cannot obtain a fair contest? Are international

James Meernik

2003-01-01

340

Indonesia: Internal Conditions, the Global Economy, and Regional Development.  

ERIC Educational Resources Information Center

|Describes recent trends in the economic and regional development of Indonesia and examines the internal and external forces influencing the process. Shows how these forces account for the rise of a strong centralized state. Discusses Indonesia's current problems. Includes tables, maps, and graphs of economic investment figures, world trade, and…

Leitner, Helga; Sheppard, Eric S.

1987-01-01

341

Nonequilibrium forces between neutral atoms mediated by a quantum field  

SciTech Connect

We study forces between two neutral atoms, modeled as three-dimensional harmonic oscillators, arising from mutual influences mediated by an electromagnetic field but not from their direct interactions. We allow as dynamical variables the center-of-mass motion of the atom, its internal degrees of freedom, and the quantum field treated relativistically. We adopt the method of nonequilibrium quantum field theory which can provide a first-principles, systematic, and unified description including the intrinsic and induced dipole fluctuations. The inclusion of self-consistent back-actions makes possible a fully dynamical description of these forces valid for general atom motion. In thermal equilibrium we recover the known forces--London, van der Waals, and Casimir-Polder--between neutral atoms in the long-time limit. We also reproduce a recently reported force between atoms when the system is out of thermal equilibrium at late times. More noteworthy is the discovery of the existence of a type of (or identification of the source of some known) interatomic force which we call the ''entanglement force,'' originating from the quantum correlations of the internal degrees of freedom of entangled atoms.

Behunin, Ryan O. [Maryland Center for Fundamental Physics, Department of Physics, University of Maryland, College Park, Maryland 20742 (United States); Hu, Bei-Lok [Maryland Center for Fundamental Physics, Department of Physics, University of Maryland, College Park, Maryland 20742 (United States); Joint Quantum Institute, University of Maryland, College Park, Maryland 20742 (United States)

2010-08-15

342

International Adoption: The Human Rights Position  

Microsoft Academic Search

International adoption is under siege, with the number of children placed dropping each of the last several years, and many countries imposing severe new restrictions. Key forces mounting the attack claim the child human rights mantle, arguing that such adoption denies heritage rights, and often involves abusive practices. Many nations assert rights to hold onto the children born within their

Elizabeth Bartholet

2010-01-01

343

International Relations, Social Studies: 6448.20.  

ERIC Educational Resources Information Center

The forces affecting relations among nations as well as the effectiveness of decision making processes in international politics are examined and analyzed by 10th through 12th grade students in the elective quinmester course clustering around political studies. Goals emphasize helping students to understand state interaction and the variables…

Coe, Rose Marie

344

A HUD Handbook. Urban Intern Training.  

ERIC Educational Resources Information Center

|The Urban Internship Program has been established to recruit and train above average graduate and undergraduate students to fill program leadership positions in the Department of Housing and Urban Development (HUD). The program provides orientation to major HUD programs to integrate the intern into the work force quickly and effectively and…

Department of Housing and Urban Development, Washington, DC.

345

International military interventions: Identification and classification  

Microsoft Academic Search

International military intervention is the movement of troops or forces of one country into the territory or territorial waters of another country, or military action by troops already stationed by one country inside another, in the context of some political issue or dispute. As such it is a discrete event, or set of discrete events, persisting in time, entailing military

Frederic S. Pearson; Robert A. Baumann

1988-01-01

346

International retail franchising: a conceptual framework  

Microsoft Academic Search

Franchising has become a major driving force in the globalisation of service businesses. Likewise, international retailing has become an important feature of global distribution systems. This has been brought about through changing socio-economic patterns, favourable political and cultural environments, and a shift from manufacturing to service based economies. Both developments have contributed to the globalisation of marketing activity. However, there

Barry Quinn; Nicholas Alexander

2002-01-01

347

Globalization, New Internationalism and the Zapatistas  

Microsoft Academic Search

This article suggests that the driving force of today's new internationalism is not a common ideology, but needs and the practical necessities of different movements within the context of the global economy. The Zapatistas are one of the movements that most have explicitly and systematically voiced a vision of a different world developed from within the old. Therefore this article

Massimo De Angelis

2000-01-01

348

Internal seiche dynamics in Lake Geneva  

Microsoft Academic Search

We analyzed season-long water level records at 12 stations around the Lake of Geneva (local name Leman) for evidence of internal seiches modified by Coriolis force and compared the results with predictions from a two-layer numerical model with real bottom topography for typical wind situations. Results are also compared with those obtained from current and temperature measurements in the lake.

U. Lemmin; C. H. Mortimer; E. Bäuerle

2005-01-01

349

Force-assembly with friction  

SciTech Connect

Previously, force-assembly has been defined as an assembly process for which a single admittance control law (i.e., a single nominal velocity in conjunction with a single mapping of forces to motions) can guarantee the proper assembly of a given pair of mating parts. As a testbed application of force-assembly, the insertion of a workpiece into a fixture consisting of multiple rigid fixture elements (fixels) is addressed. Previous work in this area has shown that, when workpiece/fixture contact is frictionless and positional error is infinitesimal, there always exists an admittance control law that will ensure the proper insertion of a workpiece into a deterministic fixture. When workpiece/fixture contact is frictionless, the workpiece/fixture contact force contains the relative positional information required to identify error-reducing motions. Friction between the workpiece and fixture, however, provides a disturbance to the geometrical information contained in the contact force. This paper addresses: (1) the identification of the conditions that must be satisfied for force-assembly with friction, and (2) the formulation and results of an optimization of the admittance control law to obtain the maximum value of friction that will satisfy the force-assembly conditions for a given workpiece/fixture combination. Results indicate that force-assembly fails when the contact forces are no longer characteristic. Forces are characteristic if the possible contact forces that may occur for one type of misalignment are unique to that type of misalignment.

Schimmels, J.M. (Marquette Univ., Milwaukee, WI (United States)); Peshkin, M.A. (Northwestern Univ., Evanston, IL (United States). Dept. of Mechanical Engineering)

1994-08-01

350

Force measurements during vibration testing  

SciTech Connect

Experimental measurements of force into a ``rigid`` test item representing a typical system level vibration test were conducted to evaluate several methods of force measurements. The methods evaluated included: (1) Direct measurement with force gages between the test item and the fixturing; (2) Measurement of the force at the shaker/fixture interface and correcting the force required to drive the fixturing using two methods, (a) mass subtraction and (b) SWAT (sum of weighted accelerations technique), (3) Force deduced from voltage and current needed to drive the test item. All of the methods worked over a limited frequency range of five to a few hundred Hertz. The widest bandwidth was achieved with force at the shaker/fixture interface with SWAT corrections and from the voltage and current measurements.

Smallwood, D.O.; Coleman, R.G.

1993-12-31

351

Imaging adhesion forces on proteins with the atomic force microscope  

NASA Astrophysics Data System (ADS)

We investigated the adhesion forces between single protein molecules and the silicon-nitride tip of an atomic force microscope. Force curves were taken on a sample with single adsorbed proteins while the tip was raster scanned laterally. Out of these force maps we can calculate several images showing for instance the topography or the adhesion force as a function of lateral position. Two systems were investigated here: actin adsorbed on mica and tubulin adsorbed on positively charged silanized surfaces, the adhesion force of the tip on the protein was smaller by about a factor of three to five compared to the force measured on the substrate. This is in agreement with previous studies of lysozyme and DNA adsorbed on mica. The data were analyzed by estimating the van der Waals force between the tip and a single protein and between the tip and a flat substrate. The measured adhesion force between the tip and the substrate can be understood by van der Waals. However in the case of the proteins the observed adhesion is larger than expected by only van der Waals forces. So we conclude that there are additional interactions determining the adhesion between the tip and the protein.

Radmacher, Manfred; Fritz, Monika; Allersma, Miriam W.; Schmidt, Christoph F.; Hansma, Paul K.

1995-03-01

352

Failed States and Casualty Phobia: Implications for Force Structure and Technology Choices.  

National Technical Information Service (NTIS)

The emergence of failed states as the principal source of international political instability and the appearance of mounting casualty phobia among U.S. political and military elites have significant force structure and technology implications. Overseas, i...

J. Record

2000-01-01

353

International migration: a global challenge.  

PubMed

Trends in international migration are presented in this multiregional analysis. Seven of the world's wealthiest countries have about 33% of the world's migrant population, but under 16% of the total world population. Population growth in these countries is substantially affected by the migrant population. The migration challenge is external and internal. The external challenge is to balance the need for foreign labor and the commitment to human rights for those migrants seeking economic opportunity and political freedom. The internal challenge is to assure the social adjustment of immigrants and their children and to integrate them into society as citizens and future leaders. Why people cross national borders and how migration flows are likely to evolve over the next decades are explained. This report also presents some ways that countries can manage migration or reduce the pressures which force people to migrate. It is recommended that receiving nations control immigration by accelerating global economic growth and reducing wars and human rights violations. This report examines the impact of immigration on international trade, aid, and direct intervention policies. Although migration is one of the most important international economic issues, it is not coordinated by an international group. The European experience indicates that it is not easy to secure international cooperation on issues that affect national sovereignty. It is suggested that countries desiring control of their borders should remember that most people never cross national borders to live or work in another country, that 50% of the world's migrants move among developing countries, and that countries can shift from being emigration to immigration countries. The author suggests that sustained reductions in migration pressure are a better alternative than the "quick fixes" that may invite the very much feared mass and unpredictable movements. PMID:12320315

Martin, P; Widgren, J

1996-04-01

354

Electricity: The Mysterious Force  

NSDL National Science Digital Library

This document examines the mysterious force of electricity. The reading will focus on the physical properties of electricity and discuss topics such as (1) The Atom of Carbon, (2) Static electricity, (3) Magnets are special, (4) Magnetic fields can produce electricity, (5) Batteries produce electricity, (6) Electricity travels in circuits, (7) Secondary energy source, (8) Making electricity, (9) Moving electricity from power plants to homes, (10) Fuels that make electricity, (11) Fossil fuel power plants, (12) Nuclear power plants, (13) Hydropower plants, (14) What's a Watt, and (15) Cost of electricity. The document also depicts illustrations of a bar magnet, turbine generator, transporting electricity, U.S. electricity production, peak demand, and energy efficiency. This resource is structured as an informational booklet to supplement your energy activities or to generate discussion questions.

2008-01-01

355

Applied Research - International Collaborative Activities  

Cancer.gov

Skip to Content Cancer Control and Population Sciences Home Applied Research Home International Collaborative Activities: International Collaborative Activities Home International Consortia & Conferences Funded Research with International Components International

356

Imaging viscoelasticity by force modulation with the atomic force microscope  

PubMed Central

Force modulation and phase sensitive detection was used to image soft surfaces with the atomic force microscope. This force modulation microscopy allows the simultaneous recording of images of the surface profile, the storage modulus, and the loss modulus of the sample. A theoretical treatment of the elastic tip-sample interaction is given. As examples, images of Langmuir-Blodgett films of a polymeric amphiphile and of a structured fatty acid are presented. ImagesFIGURE 6FIGURE 7FIGURE 8

Radmacher, M.; Tillmann, R. W.; Gaub, H. E.

1993-01-01

357

Mapping interaction forces with the atomic force microscope.  

PubMed Central

Force curves were recorded as the sample was raster-scanned under the tip. This opens new opportunities for imaging with the atomic force microscope: several characteristics of the samples can be measured simultaneously, for example, topography, adhesion forces, elasticity, van der Waals, and electrostatic interactions. The new opportunities are illustrated by images of several characteristics of thin metal films, aggregates of lysozyme, and single molecules of DNA. Images FIGURE 1 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6

Radmacher, M; Cleveland, J P; Fritz, M; Hansma, H G; Hansma, P K

1994-01-01

358

Trends of measured climate forcing agents  

NASA Astrophysics Data System (ADS)

* National Aeronautics and Space Administration, Goddard Institute for Space Studies, New York, NY 10025; and Center for Climate Systems Research, Columbia University Earth Institute, New York, NY 10025 Contributed by James E. Hansen, October 16, 2001 The growth rate of climate forcing by measured greenhouse gases peaked near 1980 at almost 5 W/m2 per century. This growth rate has since declined to 3 W/m2 per century, largely because of cooperative international actions. We argue that trends can be reduced to the level needed for the moderate "alternative" climate scenario (?2 W/m2 per century for the next 50 years) by means of concerted actions that have other benefits, but the forcing reductions are not automatic "co-benefits" of actions that slow CO2 emissions. Current trends of climate forcings by aerosols remain very uncertain. Nevertheless, practical constraints on changes in emission levels suggest that global warming at a rate +0.15 ± 0.05°C per decade will occur over the next several decades.

Hansen, James E.; Sato, Makiko

2001-12-01

359

Dynamics of Traction Force Reinforcement in Smooth Muscle Cells  

NASA Astrophysics Data System (ADS)

Mechanical forces influence cell function in various ways. For instance, the force-induced contraction or relaxation of vascular smooth muscle cells (SMCs) is critical to regulating the properties of blood vessels. Here, we study the dynamics of cellular traction forces in SMCs using micro-scale magnetic nanowires together with flexible PDMS micropost arrays. We use dual magnetic tweezers to apply a sinusoidal magnetic torque on nickel nanowires which are internalized by the SMCs. The spatial and temporal responses of the SMCs cultured on the tips of the microposts are recorded by the deflected posts. We observe a global reinforcement of the cells' traction forces upon applying a localized torque via the nanowires. Interestingly, we also find that the contractile response depends on the frequency of the applied stimulation, with a greater percentage of the SMCs showing enhanced reinforcement at lower frequencies.

Lin, Yi-Chia; Kramer, Corinne; Chen, Christopher; Reich, Daniel

2010-03-01

360

From mechanical force to RhoA activation  

PubMed Central

Throughout their lives all cells constantly experience and respond to various mechanical forces. These frequently originate externally but can also arise internally as a result of the contractile actin cytoskeleton. Mechanical forces trigger multiple signaling pathways. Several converge and result in the activation of the GTPase RhoA. In this review we focus on the pathways by which mechanical force leads to RhoA regulation, especially when force is transmitted via cell adhesion molecules that mediate either cell-matrix or cell-cell interactions. We discuss both the upstream signaling events that lead to activation of RhoA, as well as the downstream consequences of this pathway. These include not only cytoskeletal reorganization and, in a positive feedback loop, increased myosin-generated contraction, but also profound effects on gene expression and differentiation.

Lessey, Elizabeth C.; Guilluy, Christophe; Burridge, Keith

2012-01-01

361

Susceptibility of atomic force microscope cantilevers to lateral forces  

NASA Astrophysics Data System (ADS)

V-shaped cantilevers are used widely in the atomic force microscope (AFM) due to their perceived enhanced resistance to lateral forces in comparison to rectangular cantilevers. In this article, we rigorously investigate this premise, and in so doing establish that, contrary to established operating principles and intuition, V-shaped AFM cantilevers are generally more prone to the effects of lateral forces than rectangular AFM cantilevers. This finding suggests that rectangular cantilevers should be used in place of V-shaped cantilevers in applications where the effects of lateral forces are to be minimized.

Sader, John Elie

2003-04-01

362

Force treadmill for measuring vertical and horizontal ground reaction forces.  

PubMed

We constructed a force treadmill to measure the vertical, horizontal and lateral components of the ground-reaction forces (Fz, Fy, Fx, respectively) and the ground-reaction force moments (Mz, My, Mx), respectively exerted by walking and running humans. The chassis of a custom-built, lightweight (90 kg), mechanically stiff treadmill was supported along its length by a large commercial force platform. The natural frequencies of vibration were >178 Hz for Fz and >87 Hz for Fy, i.e., well above the signal content of these ground-reaction forces. Mechanical tests and comparisons with data obtained from a force platform runway indicated that the force treadmill recorded Fz, Fy, Mx and My ground-reaction forces and moments accurately. Although the lowest natural frequency of vibration was 88 Hz for Fx, the signal-to-noise ratios for Fx and Mz were unacceptable. This device greatly decreases the time and laboratory space required for locomotion experiments and clinical evaluations. The modular design allows for independent use of both treadmill and force platform. PMID:9688758

Kram, R; Griffin, T M; Donelan, J M; Chang, Y H

1998-08-01

363

The Other Side of the COIN: Minimum and Exemplary Force in British Army Counterinsurgency in Kenya  

Microsoft Academic Search

This article argues that the British government's deliberate exclusion of international law from colonial counterinsurgencies allowed the army to suppress opponents with little restraint. The oft-assumed national inhibitor, the principle of ‘minimum force’, was actually widely permissive. As a result exemplary force was employed to coerce the Kikuyu civilian population in Kenya into supporting the government rather than the insurgents.

HUW BENNETT

2007-01-01

364

The analysis of five forces framework of the saltwater pearls industry's development  

Microsoft Academic Search

This paper has analyzed the five forces within the saltwater pearls industry .The industry will have to face the huge market share and huge risk of the unstable international market. There excess competition in the industry and the consumers' power and forces are big so that the enterprises have to reposi- tion their development strategies under the changes of market

Li Fei-Xing; Yang Wei-wen

2011-01-01

365

PERSONAL EXPOSURE TO JP-8 JET FUEL VAPORS AND EXHAUST AT AIR FORCE BASES  

EPA Science Inventory

JP-8 jet fuel (similar to commercial/international jet A-1 fuel) is the standard military fuel for all types of vehicles, including the U.S. Air Force aircraft inventory. As such, JP-8 presents the most common chemical exposure in the Air Force, particularly for flight and gro...

366

Conversion of selected military forces to the use of metric measurement units  

Microsoft Academic Search

Conversion of the United States military to the International System of measurement units is in the very early stages. Little formal planning has been done to articulate the management required to complete the conversion of operational Army and Air Force units. For those operational forces tasked to provide continuous combat readiness throughout metrication, management problems associated with the conversion are

G. L. Boozer

1976-01-01

367

The Training Environment Of The Irish Defence Forces:Integrated Training, Bullying and Sexual Harassment  

Microsoft Academic Search

The training environment of the Irish Defence Forces: integrated training and bullying in the workplace In this chapter I will refer to recruit and cadet training within the defence forces in light of international trends in integrated training. Following the consideration of ‘commitment’ in terms of numbers of women recruited to the organisation in chapter five, this chapter assesses the

Tom Clonan

2000-01-01

368

The effect of muscle stiffness and damping on simulated impact force peaks during running  

Microsoft Academic Search

It has been frequently reported that vertical impact force peaks during running change only minimally when changing the midsole hardness of running shoes. However, the underlying mechanism for these experimental observations is not well understood. An athlete has various possibilities to influence external and internal forces during ground contact (e.g. landing velocity, geometrical alignment, muscle tuning, etc.). The purpose of

Benno M Nigg; Wen Liu

1999-01-01

369

The Security Council's Crisis of Legitimacy and the Use of Force  

Microsoft Academic Search

The United Nations Security Council (UNSC) occupies a unique position in the regime governing the use of force in international politics. Two key principles underpin this regime: first, a ban on the individual use of force other than for purposes of self-defence (in the face of actual or imminent attack); and second, it is the responsibility of the UNSC to

Justin Morris; Nicholas J Wheeler

2007-01-01

370

How International Law Works  

Microsoft Academic Search

How International Law Works presents a theory of international law, how it operates, and why it works. Though appeals to international law have grown ever more central to international disputes and international relations, there is no well-developed, comprehensive theory of how international law shapes policy outcomes.\\u000aFilling a conspicuous gap in the literature on international law, Andrew T. Guzman builds

Andrew T Guzman

2008-01-01

371

Questioning the Motivations for International Repositories for Nuclear Waste  

Microsoft Academic Search

Because national nuclear waste management schemes have proven to be unsuccessful, an international nuclear waste scheme has been seriously entertained by numerous individuals and agencies. In this article I bring into question the range of motivating forces have been offered by such proponents. I conclude that the motivations for international repositories are so inflected with social, ethical and political problems

Alan Marshall

2005-01-01

372

The Role of Rewards in Conflictual International Interactions  

Microsoft Academic Search

Models of international conflict often omit the option of offering rewards as a means of exerting influence. The author has developed a revised version of Bueno de Mesquita and Lalman's (1992) international interaction game that allows states either to offer rewards or threaten military force once they have made political demands and their adversary has rejected them. After laying out

Gerald L. Sorokin

1996-01-01

373

Behavior of Bucky Ball under extreme Internal and External Pressures  

Microsoft Academic Search

We study the behavior of the C60 molecule under very high internal and external pressure using Tersoff potential. As a result, we calculate the critical internal and external pressures leading to its instability. We also calculate stretching force constant, breathing mode frequency and bulk modulus of this molecule. The data estimated here at zero pressure agrees closely to that obtained

Narinder Kaur; K. Dharamvir; V. K. Jindal

2006-01-01

374

Behaviour of a Buckyball under Internal and External Pressures  

Microsoft Academic Search

We study the behaviour of the C60 molecule under very high internal or external pressure using Tersoff as well as Brenner potentials. As a result, we estimate the critical internal and external pressures that lead to its instability. We also calculate stretching force constant and bulk modulus of this molecule at several pressures under which the molecule remains stable. The

Narinder Kaur; Shuchi Gupta; Keya Dharamvir; V. K. Jindal

2007-01-01

375

War and the International Trading System in the Twentieth Century  

Microsoft Academic Search

Wars have been the main forces shaping the international trading system in the twentieth century. The early years of the twentieth century were dominated by the international gold standard. But as a result of World War I, this system was replaced by the troubled gold exchange standards of the 1920s and 1930s. As a result of World War II the

Hugh Rockoff

2011-01-01

376

Force-Induced DNA Slippage  

PubMed Central

DNA containing repetitive sequences displays richer dynamics than heterogeneous sequences. In the genome the number of repeat units of repetitive sequences, known as microsatellites, may vary during replication by DNA slippage and their expansion gives rise to serious disorders. We studied the mechanical properties of repetitive DNA using dynamic force spectroscopy and found striking differences compared with ordinary heterogeneous sequences. Repetitive sequences dissociate at lower forces and elongate above a certain threshold force. This yield force was found to be rate dependent. Following the rapid stretching of the DNA duplex, the applied force relaxes by stepwise elongation of this duplex. Conversely, contraction of the DNA duplex can be observed at low forces. The stepwise elongation and shortening is initiated by single slippage events, and single-molecule experiments might help to explain the molecular mechanisms of microsatellites formation. In addition to the biological importance, the remarkable properties of repetitive DNA can be useful for different nanomechanical applications.

Kuhner, Ferdinand; Morfill, Julia; Neher, Richard A.; Blank, Kerstin; Gaub, Hermann E.

2007-01-01

377

Role of Special Forces in Information Operations.  

National Technical Information Service (NTIS)

This thesis examines the role of the Special Forces Group in Information Operations. It focuses on providing information to the Joint Task Force planner and the Special Forces unit leaders. It provides the Joint Forces Commander and planner an understandi...

F. C. Gottschalk

2000-01-01

378

Coriolis Force on Your Arms  

Microsoft Academic Search

The Coriolis force is a sideward force that acts on a rotating object as it moves toward or away from the center of rotation. It is important to long-range artillery and the formation of tornados, but we seldom experience this force on a human scale, unless we play on a merry-go-round or similar apparatus.1 This note describes a simple activity

Robert Johns

2003-01-01

379

Mechanical forces of electromagnetic origin  

Microsoft Academic Search

EXPERIMENTS have been reported which verified that at low frequencies a time-varying polarisation P in a dielectric, if taking place in a magnetic field H, results in a mechanical force of density P×mu0H. This force is not predicted by the Minkowski energy momentum tensor, but the Abraham form of that tensor gives a force density in an homogeneous isotropic body

G. B. Walker

1976-01-01

380

Dynamic Force Microscopy and Spectroscopy  

Microsoft Academic Search

Atomic force microscopy has evolved into an imaging method that yields fine structural details on live, biological samples\\u000a like proteins, nucleotides, membranes and cells in their physiological environment and at ambient conditions. Due to its high\\u000a lateral resolution and sensitive force detection capability, the exciting option of measuring inter- and intra-molecular forces\\u000a of biomolecules on the single-molecule level has also

Ferry Kienberger; Hermann Gruber; Peter Hinterdorfer

381

A Constant Force Dielectrophoretic Cell  

NASA Astrophysics Data System (ADS)

We fabricated an especially designed cell to study colloidal suspension under an isomotive dielectrophoresis force. Under such conditions, the effects of a uniaxial force on gel structure and crystallization can be studied with an absolute control on its magnitude. Since the force is horizontal by design, we can take advantage of the higher resolution on the horizontal axis to obtain more precise particle locations. Preliminary results are shown.

Kilfoil, Maria; Pelletier, Vincent; Scott, Andrew; Haldane, Allan

2006-03-01

382

Temperature dependence of Casimir force  

NASA Astrophysics Data System (ADS)

Most of the experimental work till date on Casimir forces have been performed at or near room temperature. We report on our measurements of Casimir forces performed at liquid helium and liquid nitrogen temperatures using gold coated sphere and plate. These measurements were performed on a home built Atomic Force Microscope with a phase locked loop to track the frequency shift. We will discuss the results in the context of current theoretical understanding of temperature dependence in the sphere -- plate geometry.

Xu, Jun; Castillo-Garza, Rodrigo; Schafer, Robert; Mukhopadhyay, Shomeek; Mohideen, Umar

2012-02-01

383

China's Position on International TerrorismA Survey of Government Releases and Papers  

Microsoft Academic Search

The literature on terrorism appears to be burdened by a continuing and often acrimonious debate over its definition and nature. The 9\\/11 incident demonstrates that terrorism in today's world tends to be multi-faceted. All states use force or at least accept the use of force as legitimate in international relations. As such, the use of force per se cannot be

Jagannath Prasad Panda

2006-01-01

384

Force As A Momentum Current  

NASA Astrophysics Data System (ADS)

Advantages of a neo-Cartesian approach to classical mechanics are noted. If conservation of linear momentum is the fundamental principle, Newton's three laws become theorems. A minor paradox in static Newtonian mechanics is identified, and solved by reinterpreting force as a current of momentum. Contact force plays the role of a mere midwife in the exchange of momentum; however, force cannot be eliminated from physics because it provides the numerical value for momentum current. In this sense, in a neo-Cartesian formulation of mechanics the concept of force becomes strengthened rather than weakened.

Múnera, Héctor A.

2010-07-01

385

Antibacterial Drug Development Task Force  

Center for Drug Evaluation (CDER)

... The CDER Antibacterial Drug Development Task Force has been created to support the development of new antibacterial drugs. ... More results from www.fda.gov/drugs/developmentapprovalprocess/developmentresources

386

Quasipatterns in parametrically forced systems  

NASA Astrophysics Data System (ADS)

We examine two mechanisms that have been put forward to explain the selection of quasipatterns in single- and multifrequency forced Faraday wave experiments. Both mechanisms can be used to generate stable quasipatterns in a parametrically forced partial differential equation that shares some characteristics of the Faraday wave experiment. One mechanism, which is robust and works with single-frequency forcing, does not select a specific quasipattern: we find, for two different forcing strengths, 12-fold and 14-fold quasipatterns. The second mechanism, which requires more delicate tuning, can be used to select particular angles between wavevectors in the quasipattern.

Rucklidge, A. M.; Silber, M.

2007-05-01

387

Characterization of interparticle forces in the packing of cohesive fine particles.  

PubMed

We numerically investigate force structures in the packing of fine cohesive particles using the discrete element method. By changing the particle size and therefore the van der Waals force, the effect of cohesion on the normal contact force and the total normal force, which is the sum of the normal contact forces and the van der Waals forces, is analyzed. It is shown that, with decreasing particle size, the normal contact forces become more uniform and have a narrower and more symmetric distribution, while the distributions of the total normal forces widen. Spatial correlation between the interparticle forces exists for the packing of coarse noncohesive particles. As the particle size decreases, this correlation becomes weaker for the contact forces but stronger for the total normal forces. A comparison between the effective weight of particles and the internal force structure suggests that there are differences between the particle-particle and particle-wall forces. The bimodal distribution of the effective weight indicates that there may exist two phases in the packings when cohesion is present, governed by the compressive and tensile stresses. PMID:18851026

Yang, R Y; Zou, R P; Yu, A B; Choi, S K

2008-09-05

388

Multiple robot force control with delayed force measurements  

Microsoft Academic Search

With the rapid progress of the robotic technology, it is becoming increasingly common to have multiple robots working together for material transport, cooperative assembly, etc. To ensure the proper handling of the load, especially if it is fragile or needs to be moved rapidly, the constraint force needs to be carefully managed. Tight force coordination is possible if all robots

Gustavo Montemayor; John T. Wen

2004-01-01

389

Stability of Trilateral Forces: II, Large Symmetric Force  

SciTech Connect

For large symmetric offensive forces, as for small, at few weapons per missile all forces are reserved, costs are constant, and configurations are stable. At many weapons permissile, no weapons are reserved, first strike costs decrease, fractionation is attractive, and stability degrades. These results a due to symmetries that would not be degraded by additional symmetric opponents.

Canavan, G.H.

1998-09-17

390

Particle force light scattering: A technique for measuring interparticle forces  

Microsoft Academic Search

Colloidal stability is governed by interparticle forces, but for nanocolloids, both theory and experimental data are scarce. This thesis aims to develop a new experimental technique for measuring (nano)colloidal forces. The first part of my thesis will extend our current technique, video microscopy differential electrophoresis (VMDE), to enable measurements on linear colloidal triplets. By using a third particle as a

Gretchen L. Holtzer

2005-01-01

391

FRAX ® International Task Force of the 2010 Joint International Society for Clinical Densitometry & International Osteoporosis Foundation Position Development Conference  

Microsoft Academic Search

Osteoporosis is a serious worldwide epidemic. FRAX® is a web-based tool developed by the Sheffield WHO Collaborating Center team, that integrates clinical risk factors and femoral neck BMD and calculates the 10 year fracture probability in order to help health care professionals identify patients who need treatment. However, only 31 countries have a FRAX® calculator. In the absence of a

Jane A. Cauley; Ghada El-Hajj Fuleihan; Marjorie M. Luckey

392

Aerodynamic tower shake force analysis for VAWT  

Microsoft Academic Search

Vertical axis wind turbines (VAWT) are subjected to blade lift forces which vary continuously in both magnitude and direction. These blade lift forces are transmitted via the blade support arms to the tower. The resulting tower force vector is a composite of: a downwind and a crosswind average force component, rotating force vectors, and force vectors oscillating in the crosswind

J. L. Loth

1985-01-01

393

Risk assessment in international operations  

SciTech Connect

During international peace-keeping missions, a diverse number of non-battle hazards may be encountered, which range from heavily polluted areas, endemic disease, toxic industrial materials, local violence, traffic, and even psychological factors. Hence, elevated risk levels from a variety of sources are encountered during deployments. With the emphasis within the Swedish military moving from national defense towards prioritization of international missions in atypical environments, the risk of health consequences, including long term health effects, has received greater consideration. The Swedish military is interested in designing an optimal approach for assessment of health threats during deployments. The Medical Intelligence group at FOI CBRN Security and Defence in Umea has, on request from and in collaboration with the Swedish Armed Forces, reviewed a variety of international health threat and risk assessment models for military operations. Application of risk assessment methods used in different phases of military operations will be reviewed. An overview of different international approaches used in operational risk management (ORM) will be presented as well as a discussion of the specific needs and constraints for health risk assessment in military operations. This work highlights the specific challenges of risk assessment that are unique to the deployment setting such as the assessment of exposures to a variety of diverse hazards concurrently.

Stricklin, Daniela L. [FOI, Swedish Defence Research Agency, CBRN Security and Defence, Umea, SE-90182 (Sweden)], E-mail: daniela.stricklin@foi.se

2008-11-15

394

Hydration force in the atomic force microscope: A computational study.  

PubMed Central

Using a hard sphere model and numerical calculations, the effect of the hydration force between a conical tip and a flat surface in the atomic force microscope (AFM) is examined. The numerical results show that the hydration force remains oscillatory, even down to a tip apex of a single water molecule, but its lateral extent is limited to a size of a few water molecules. In general, the contribution of the hydration force is relatively small, but, given the small imaging force ( approximately 0.1 nN) typically used for biological specimens, a layer of water molecules is likely to remain "bound" to the specimen surface. This water layer, between the tip and specimen, could act as a "lubricant" to reduce lateral force, and thus could be one of the reasons for the remarkably high resolution achieved with contact-mode AFM. To disrupt this layer, and to have a true tip-sample contact, a probe force of several nanonewtons would be required. The numerical results also show that the ultimate apex of the tip will determine the magnitude of the hydration force, but that the averaged hydration pressure is independent of the radius of curvature. This latter conclusion suggests that there should be no penalty for the use of sharper tips if hydration force is the dominant interaction between the tip and the specimen, which might be realizable under certain conditions. Furthermore, the calculated hydration energy near the specimen surface compares well with experimentally determined values with an atomic force microscope, providing further support to the validity of these calculations.

Ho, R; Yuan, J Y; Shao, Z

1998-01-01

395

International Law Students Association (ILSA) International Conference  

Microsoft Academic Search

This paper analyses the making of a new order in seventeenth-century European international society by taking international institutions and their development in the 'longue durée ' as markers of historical change. It assesses the impact of the peace process of Westphalia on both core and procedural international institutions. The argument is that several developments in the seventeenth century, including the

Belo Horizonte

396

The internal dynamic of international migration systems  

Microsoft Academic Search

In this paper I provide a conceptualization of international migration networks, which can be used to identify and integrate the internal components of migration systems, and formalize the relationships in an analytic model of the internal network dynamic. With the use of the operationalized model, and microlevel and macrolevel data for guestworkers in Germany during the period 1970 to 1989,

B. Waldorf

1996-01-01

397

Community College Internal Auditors: Internal Audit Guidebook.  

ERIC Educational Resources Information Center

|This guidebook includes information compiled by the "Audit Manual" committee of Community College Internal Auditors (CCIA) from several California community college districts regarding their internal auditing practices. The first section of the guidebook discusses the purpose of internal audits, indicating that audits assist members of the…

Jones, Ronna; And Others

398

Exotic nuclei and nuclear forces  

NASA Astrophysics Data System (ADS)

I overview new aspects of the structure of exotic nuclei as compared to stable nuclei, focusing on several characteristic effects of nuclear forces. The shell structure of nuclei has been proposed by Mayer and Jensen, and has been considered to be kept valid basically for all nuclei, with well-known magic numbers, 2, 8, 20, 28, 50, …. Nuclear forces were shown, very recently, to change this paradigm. It will be presented that the evolution of shell structure occurs in various ways as more neutrons and/or protons are added, and I will present basic points of this shell evolution in terms of the monopole interaction of nuclear forces. I will discuss three types of nuclear forces. The first one is the tensor force. The tensor force is one of the most fundamental nuclear forces, but its first-order effect on the shell structure has been clarified only recently in studies on exotic nuclei. The tensor force can change the spin-orbit splitting depending on the occupation of specific orbits. This results in changes of the shell structure in many nuclei, and consequently some of Mayer-Jensen's magic numbers are lost and new ones emerge, in certain nuclei. This mechanism can be understood in an intuitive way, meaning that the effect is general and robust. The second type of nuclear forces is central force. I will show a general but unknown property of the central force in the shell-model Hamiltonian that can describe nuclear properties in a good agreement with experiment. I will then demonstrate how it can be incorporated into a simple model of the central force, and will discuss how this force works in the shell evolution. Actually, by combining this central force with the tensor force, one can understand and foresee how the same proton-neutron interaction drives the shell evolution, for examples such as Sn/Sb isotopes, N = 20 nuclei and Ni/Cu isotopes. The distribution of single-particle strength is discussed also in comparison to (e,e?p) experiment on 48Ca. The shell evolution affects shapes of nuclei through Jahn-Teller-type mechanism, and a very interesting example with exotic Si isotopes is discussed. The third type of nuclear force is a three-body force, which originates in the ? particle excitation as proposed by Fujita and Miyazawa many years ago. This force is shown to produce a repulsive interaction between valence neutrons after averaging effects from the third nucleon in the core. The same three-body force is responsible for neutron stars. By including such effects of the three-body force, one can predict the correct drip line of oxygen isotopes, for instance. Thus, the landscape of atomic nuclei varies in going from stable to exotic nuclei due to particular nuclear forces, leading to a paradigm shift. This paper overviews some basic ideas and selected examples.

Otsuka, Takaharu

2013-01-01

399

Internal Audit Manual.  

National Technical Information Service (NTIS)

The Manual provides uniform policies and procedures for all Department of Defense (DoD) Internal Audit, Internal Review, and Nonappropriated Fund Audit Organizations to follow when conducting internal audits of DoD operations, systems, programs, and funct...

C. Rawdon

1990-01-01

400

Historical Perspective on 'Hollow Forces'.  

National Technical Information Service (NTIS)

Senior Department of Defense (DOD) leaders have invoked the specter of a 'hollow force' to describe what could happen to the U.S. Armed Forces if significant cuts to the defense budget are enacted. While some Members and staff might be familiar with the '...

A. Feickert S. Daggett

2012-01-01

401

Intermolecular Forces: Solids and Liquids  

NSDL National Science Digital Library

General chemistry WebCT exam/quiz questions. The Intermolecular Forces: Solids and Liquids topic covers the forces that exist between atoms and molecules in solids and liquids, and how these affect properties such as boiling point, conductivity, and lattice energy.

2007-09-07

402

Electrostatic forces for personnel restraints  

Microsoft Academic Search

The feasibility of utilizing electrostatic forces for personnel retention devices on exterior spacecraft surfaces was analyzed. The investigation covered: (1) determination of the state of the art; (2) analysis of potential adhesion surfaces; (3) safety considerations for personnel; (4) electromagnetic force field determination and its effect on spacecraft instrumentation; and (5) proposed advances to current technology based on documentation review,

N. Ashby; J. Ciciora; R. Gardner; K. Porter

1977-01-01

403

Forced Deviation, Conformity, and Commitment  

Microsoft Academic Search

This paper considers the effects of an initial period of “forced” nonconformity on commitment to an independent position in later trials of an Asch-type experiment. Nonconformity was “forced” in the sense that experimental subjects' choices were made to appear deviant by manipulation of the choices of the fictitious discrepant majority who “responded” after experimental subjects. Compared with control subjects who

Gerald T. Slatin

1974-01-01

404

Climate forcing by stratospheric aerosols  

Microsoft Academic Search

We illustrate how climate forcing by stratospheric aerosols depends on aerosol properties. The climate forcing is a function of aerosol size distribution, but the size dependence can be described well by a single parameter: the area-weighted mean radius, reff. If reff is greater than about 2mum, the global average greenhouse effect of the aerosols exceeds the albedo effect, causing a

Andrew Lacis; James Hansen; Makiko Sato

1992-01-01

405

Hebrew as a Binding Force.  

ERIC Educational Resources Information Center

The role of the Hebrew language as a cohesive force and the history of modern Hebrew instruction are chronicled. It is proposed that despite the scattering of its speakers and periods of use only as a literary or business language, Hebrew has been a binding force for the Jewish people. It was with considerable struggle that Hebrew gained…

Fischler, Ben-Zion

1990-01-01

406

Marine Forces Reserve in Transition.  

National Technical Information Service (NTIS)

The last 5 years have demonstrated that the Marine Corps Reserve is a full partner in the Total Force Marine Corps. Marine Forces Reserve remains committed to the rapid and efficient activation of combat-ready ground, air, and logistics units, as well as ...

J. W. Bergman

2006-01-01

407

Force Generation by Flapping Foils  

NASA Astrophysics Data System (ADS)

Aquatic animals like fish use flapping caudal fins to produce axial and cross-stream forces. During WW2, German scientists had built and tested an underwater vehicle powered by similar flapping foils. We have examined the forces produced by a pair of flapping foils. We have examined the forced produced by a pair of flapping foils attached to the tail end of a small axisymmetric cylinder. The foils operate in-phase (called waving), or in anti-phase (called clapping). In a low-speed water tunnel, we have undertaken time-dependent measurements of axial and cross-stream forces and moments that are exerted by the vortex shedding process over the entire body. Phase-matched LDV measurements of vorticity-velocity vectors, as well as limited flow visualization of the periodic vortex shedding process have also been carried out. The direction of the induced velocity within a pair of shed vortices determines the nature of the forces produced, viz., thrust or drag or cross-stream forces. The clapping mode produces a widely dispersed symmetric array of vortices which results in axial forces only (thrust and rag). On the other hand, the vortex array is staggered in the waving mode and cross-stream (maneuvering) forces are then generated.

Bandyopadhyay, P. R.; Donnelly, M.

1996-11-01

408

Force Limited Vibration Testing Monograph.  

National Technical Information Service (NTIS)

The practice of limiting the shaker force in vibration tests was investigated at the NASA Jet Propulsion Laboratory (JPL) in 1990 after the mechanical failure of an aerospace component during a vibration test. Now force limiting is used in almost every ma...

T. D. Scharton

1997-01-01

409

How Does Force Affect Motion?  

ERIC Educational Resources Information Center

|Whether playing soccer at recess, walking to lunch, or sitting at their desk, children encounter forces every moment of their lives. The connection between force and motion is absolutely amazing to children, so anyone working with them better be prepared for the battery of tough questions they ask: "What made the ball move that way? Why does a…

Darling, Gerald

2012-01-01

410

Gingival response to orthodontic force  

Microsoft Academic Search

Orthodontic tooth movement is brought about by prolonged application of force on the attachment apparatus. This results in cellular and extracellular changes within the periodontium. As shown in numerous studies, tooth movement is achieved after the remodeling of alveolar bone and the response of the periodontal ligament to the mechanical force. Although gingival changes have also been found to be

Meir Redlich; Shmuel Shoshan; Aaron Palmon

1999-01-01

411

Climate Forcing by Anthropogenic Aerosols  

Microsoft Academic Search

Although long considered to be of marginal importance to global climate change, tropospheric aerosol contributes substantially to radiative forcing, and anthropogenic sulfate aerosol in particular has imposed a major perturbation to this forcing. Both the direct scattering of short-wavelength solar radiation and the modification of the shortwave reflective properties of clouds by sulfate aerosol particles increase planetary albedo, thereby exerting

R. J. Charlson; S. E. Schwartz; J. M. Hales; R. D. Cess; J. A. Coakley Jr.; J. E. Hansen; D. J. Hofmann

1992-01-01

412

Light Forces In Cavity QED  

Microsoft Academic Search

Mirrors are ideal tools for controlling the optical and motional properties of an atom. To understand the physics of the light force in a cavity, and to explain why this force can be so much larger than in free space, we present an intuitive corpuscular picture based on the notion of cavity-enhanced photon scattering. We also discuss a nonintuitive phenomenon

Gerhard Rempe; Karim Murr

2006-01-01

413

Driving Forces Behind Informal Sanctions  

Microsoft Academic Search

This paper investigates the driving forces behind informal sanctions in cooperation games and the extent to which theories of fairness and reciprocity capture these forces. We find that cooperators' punishment is almost exclusively targeted toward the defectors, but the latter also impose a considerable amount of spiteful punishment on the cooperators. However, spiteful punishment vanishes if the punishers can no

Armin Falk; Ernst Fehr; Urs Fischbacher

2005-01-01

414

Army and Multinational Force Compatibility.  

National Technical Information Service (NTIS)

As part of its Force XXI development program, the U.S. Army is 'digitizing' the force: interweaving its various levels of command with sophisticated information technologies to provide a clear and accurate shared picture of the battlespace, or area of ope...

M. Zanini J. M. Taw

2000-01-01

415

Underlagsbehob vid Signaturanpassning foer Internationella Insatser En Foerstudie (Prerequisites for Signature Management in International Operations A Preliminary Study).  

National Technical Information Service (NTIS)

The Swedish armed forces are being more and more oriented towards international operations. This implies that the signature solutions of Swedish equipment must be adapted to international environments. The purpose of this preliminary study is to determine...

S. Nilsson A. Hagard C. Nelsson S. Nyberg R. Persson J. Rahm

2004-01-01

416

Examination of the Interrelationship between the Structure of Financial Management and the Internal Audit Function within the Department of Defense.  

National Technical Information Service (NTIS)

This thesis examines the relationship between comptroller functions and internal audit functions within the Department of the Navy and the Department of the Air Force. Comptroller functions and internal audit functions are two significant control systems ...

F. R. Davis

1986-01-01

417

International Conference on Thermal and Environmental Barrier Coatings held at Kloster Irsee, Germany, on 17-22 Aug 2003.  

National Technical Information Service (NTIS)

An international conference on 'Thermal and Environmental Barrier Coatings' was held at the Swabian Conference Center, Irsee, Germany, under the auspices of Engineering Conferences International and with partial financial support from both the Air Force O...

D. R. Clarke

2004-01-01

418

How Predictive Is Grip Force Control in the Complete Absence of Somatosensory Feedback?  

ERIC Educational Resources Information Center

|Grip force control relies on accurate internal models of the dynamics of our motor system and the external objects we manipulate. Internal models are not fixed entities, but rather are trained and updated by sensory experience. Sensory feedback signals relevant object properties and mechanical events, e.g. at the skin-object interface, to modify…

Nowak, Dennis A.; Glasauer, Stefan; Hermsdorfer, Joachim

2004-01-01

419

CIVIL CONFLICT AND FORCED MIGRATION: THE MICRO DETERMINANTES AND THE WELFARE LOSSES OF DISPLACEMENT IN COLOMBIA  

Microsoft Academic Search

During the last decade, forced internal displacement in Colombia has been a growing phenomenon closely linked to the escalation of the internal armed conflict - particularly in rural areas. The displacement problem has affected nearly every region and vulnerable groups of the population. Two emerging policy questions are whether the magnitude of the response to this problem has been proportional

Ana Maria Ibáñez; Carlos Eduardo Vélez

2005-01-01

420

Quantifying immediate radiative forcing by black carbon and organic matter with the Specific Forcing Pulse  

NASA Astrophysics Data System (ADS)

We propose a measure to quantify climate warming or cooling by pollutants with atmospheric lifetimes of less than one year: the Specific Forcing Pulse (SFP). SFP is the amount of energy added to the Earth system per mass of pollutant emitted. Global average SFP for black carbon, including atmosphere and cryosphere, is 1.12 GJ g-1 and that for organic matter is -0.061 GJ g-1. We provide regional values for black carbon (BC) and organic matter (OM) emitted from 23 source-region combinations, divided between atmosphere and cryosphere impacts and identifying forcing by latitude. Regional SFP varies by about 40% for black carbon. This variation is relatively small because of compensating effects; particles from regions that affect ice albedo typically have shorter atmospheric lifetimes because of lower convection. The ratio between BC and OM SFP implies that, for direct forcing, an OM:BC mass ratio of 15 has a neutral effect on top-of-atmosphere direct forcing for any region, and any lower ratio induces direct warming. However, important processes, particularly cloud changes that tend toward cooling, have not been included here. We demonstrate ensemble adjustment, in which we produce a "best estimate" by combining a suite of diverse but simple models and enhanced models of greater complexity. Adjustments for black carbon internal mixing and for regional variability are discussed; regions with convection are implicated in greater model diversity. SFP expresses scientific uncertainty and separates it from policy uncertainty; the latter is caused by disagreements about the relevant time horizon, impact, or spatial scale of interest. However, metrics used in policy discussions, such as global warming potentials, are easily derived from SFP. Global-average SFP for biofuel and fossil fuel emissions translates to a 100-year GWP of about 760 for black carbon and -40 for organic matter when snow forcing is included. Ensemble-adjusted estimates of atmospheric radiative impact by black and organic matter using year 2000 emissions are +0.46 W m-2 and -0.17 W m-2, respectively; anthropogenic forcing is +0.38 W m-2 and -0.12 W m-2. The black carbon value is only 11% higher than that of the Intergovernmental Panel on Climate Change (IPCC), although this value includes enhanced absorption due to internal mixing.

Bond, T. C.; Zarzycki, C.; Flanner, M. G.; Koch, D. M.

2010-06-01

421

Snapshot of Air Force Psychiatry  

PubMed Central

In line with Psychiatry 2009’s mission to strengthen its global presence as a leading source of evidence-based information for practicing clinicians, we are pleased to launch the new column, “Psychiatric Clinics from Around the World.” This series will enable readers to become familiar with facilities around the world that provide psychiatric care. We hope you find the column interesting. We start the series with a column featuring Wilford Hall Medical Center, the flagship psychiatric facility of the United States Air Force. United States Air Force psychiatry plays a vital role in Operation Iraqi Freedom and Operation Enduring Freedom (Afghanistan). Outside of the military, little is known about US Air Force psychiatry and the Wilford Hall Medical Center. Wilford Hall Medical Center is the US Air Force’s flagship hospital and premiere psychiatric hospital. This article briefly discusses the history of Wilford Hall Medical Center and its psychiatric contributions to the wars in Iraq and Afghanistan.

McKinnon, Nicholas D.; Joshi, Kaustubh G.; Faubion, Matthew D.

2009-01-01

422

CBER's International Program  

Center for Biologics Evaluation and Research (CBER)

... to interactions with international organizations and international regulatory authorities for biologics. Contact Information: ... More results from www.fda.gov/biologicsbloodvaccines/internationalactivities

423

Simultaneous imaging of surface and magnetic forces  

NASA Astrophysics Data System (ADS)

We demonstrate quantitative force imaging of long-range magnetic forces simultaneously with near-surface van-der-Waals and contact-mechanics forces using intermodulation atomic force microscopy. Magnetic forces at the 200 pN level are separated from near-surface forces at the 30 nN level. Imaging of these forces is performed in both the contact and non-contact regimes of near-surface interactions.

Forchheimer, Daniel; Platz, Daniel; Tholén, Erik A.; Haviland, David B.

2013-07-01

424

Gravity and Orbits: Gravitational Force  

NSDL National Science Digital Library

This Science Object is the second of three Science Objects in the Gravity and Orbits SciPack. It investigates the variables that influence gravitational forces acting on objects. Mass is a measure of the amount of matter that makes up an object (regardless of where that object is located) and weight is a measure of the gravitational force acting on an object. The strength of the gravitational force between masses is proportional to the product of the masses and inversely proportional to the square of the distance between them. Gravity will cause all objects at the same distance from Earth's surface to fall toward Earth with the same acceleration regardless of their mass. Learning Outcomes:� Identify variables that affect the strength of the gravitational force acting between any two objects.� Provide a quantitative description of the relationship between the mass of two object and the gravitational force between them.� Provide a qualitative description of the relationship between the mass of two objects and the gravitational force between them.� Provide a quantitative description of the relationship between distance and gravitational force. � Provide a qualitative description of the inverse square relationship.� Recognize the effect of air resistance on object falling near Earth's surface, and thus be able to explain why two objects with different masses, at the same distance from Earth's surface, will have equal accelerations if air resistance is ignored.

National Science Teachers Association (NSTA)

2006-11-01

425

Electrostatic Force in Blowing Snow  

NASA Astrophysics Data System (ADS)

Separation of electrostatic charge during the transport of particles by wind adds a force to the gravitational and fluid forces that determine trajectories of particles moving by saltation. Evaluating this electrostatic force requires the electric field strength very near the saltation surface, and charge-to-mass ratios for the moving particles. Field mill readings 4 cm above the surface in a moderate blizzard showed electric field strength as high as +30 kV m-1. Another experiment gave charge-to-mass ratios of individual saltation particles in low-level drifting that ranged between +72 C kg-1 and -208 C kg-1. From these measurements, we estimated electrostatic forces as large as the gravitational force on some saltating particles. Including forces of this magnitude in the equations of motion significantly alters predicted saltation trajectories from those for uncharged particles. Predictions appear reasonable that for some saltating particles, the electrostatic force prevents new surface impacts. These results should help improve models of energy transfer in the planetary boundary layer during blizzards and sandstorms.

Schmidt, D. S.; Schmidt, R. A.; Dent, J. D.

426

Analysis of the Reserve Forces in a Total Force Concept.  

National Technical Information Service (NTIS)

The basic question regarding the optimum ratio of Active Army to Reserve Component forces has never been satisfactorily answered. One of the contributing reasons for the information gap is a lack of understanding between Active Army and Reserve Components...

F. H. Lawson

1972-01-01

427

Relative microelastic mapping of living cells by atomic force microscopy.  

PubMed Central

The spatial and temporal changes of the mechanical properties of living cells reflect complex underlying physiological processes. Following these changes should provide valuable insight into the biological importance of cellular mechanics and their regulation. The tip of an atomic force microscope (AFM) can be used to indent soft samples, and the force versus indentation measurement provides information about the local viscoelasticity. By collecting force-distance curves on a time scale where viscous contributions are small, the forces measured are dominated by the elastic properties of the sample. We have developed an experimental approach, using atomic force microscopy, called force integration to equal limits (FIEL) mapping, to produce robust, internally quantitative maps of relative elasticity. FIEL mapping has the advantage of essentially being independent of the tip-sample contact point and the cantilever spring constant. FIEL maps of living Madine-Darby canine kidney (MDCK) cells show that elasticity is uncoupled from topography and reveal a number of unexpected features. These results present a mode of high-resolution visualization in which the contrast is based on the mechanical properties of the sample.

A-Hassan, E; Heinz, W F; Antonik, M D; D'Costa, N P; Nageswaran, S; Schoenenberger, C A; Hoh, J H

1998-01-01

428

Analysis of hystereses in force length and force calcium relations.  

PubMed

Analysis of the hystereses in the force-length relationship at constant Ca(2+) concentration and in the force-calcium relationship at constant sarcomere length (SL) provides insight into the mechanisms that control cross-bridge (XB) recruitment. The hystereses are related here to two mechanisms that regulate the number of strong XBs: the cooperativity, whereby the number of strong XBs determines calcium affinity, and the mechanical feedback, whereby the shortening velocity determines the duration for which the XBs are in the strong state. The study simulates the phenomena and defines the role of these feedbacks. The model that couples calcium kinetics with XB cycling was built on Simulink software (Matlab). Counterclockwise (CCW) hysteresis, wherein the force response lags behind the SL oscillations, at a constant calcium level, is obtained in the force-length plane when neglecting the mechanical feedback and accounting only for the cooperativity mechanism. Conversely, the force response precedes the SL oscillations, yielding a clockwise (CW) hysteresis when only the mechanical feedback is allowed to exist. In agreement with experimental observations, either CW or CCW hysteresis is obtained when both feedbacks coexist: CCW hystereses are obtained at low frequencies (<3 Hz), and the direction is reversed to CW at higher frequencies (>3 Hz). The cooperativity dominates at low frequencies and allows the muscle to adapt XB recruitment to slow changes in the loading conditions. The changeover frequency from CCW to CW hysteresis defines the velocity limit above which the muscle absorbs rather than generates energy. The hysteresis in the force-calcium relation is conveniently explained by the same cooperativity mechanism. We propose that a single cooperativity mechanism that depends on the number of strong XBs can explain the hystereses in the force-length as well as in the force-calcium relationships. PMID:15598871

Yaniv, Yael; Sivan, Raphael; Landesberg, Amir

2005-01-01

429

The Army Special Operations Forces Role in Force Projection  

Microsoft Academic Search

ABSTRACT AUTHOR:,Jack C. Zeigler Jr. TITLE: The Army Special Operations Forces Role in Force Projection FORMAT:,Strategy Research Project DATE:,07 April 2003, PAGES: 30,CLASSIFICATION: Unclassified President George W. Bush summarized,his National Security Strategy in a speech,to West Point cadets in June 2002 when he stated, “If we wait for threats to fully materialize, we will have waited too long. In the

Colonel Jack; C. Zeigler

430

Optical forces in plasmonic nanoantennas  

SciTech Connect

The optical forces acting on nanoparticles in V-shaped plasmonic resonators with a high local-field gain have been investigated. Two versions are considered, which make it possible to implement either attractive or repulsive gradient optical forces. A plasmonic resonator is proposed, which can focus 350-nm radiation and implement a repulsive gradient force. It has been shown for the first time that a perturbation induced by a nanoparticle redistributes the field in the resonator so that additional intensity peaks arise in both versions to hold the nanoparticle in the resonator by forming an optical trap. (nanooptics)

Shalin, A S; Sukhov, S V

2012-04-30

431

Pendulum for precision force measurement  

NASA Astrophysics Data System (ADS)

A pendulum and a method for correcting the restoring force of the pendulum are proposed for realizing an instrument based on the levitation mass method without the use of pneumatic linear bearings. As an example a material tester using the pendulum, which evaluates the mechanical response of general objects against impact forces, is developed. The characteristics of the restoring force are accurately determined using the same instrument under the free-swing condition without the object under test. To demonstrate the high performance of the developed instrument, the impact response of a gel block is accurately determined. The possible applications of the developed method are discussed.

Fujii, Yusaku

2006-03-01

432

Force Measurement Enabling Precise Analysis by Dynamic Force Spectroscopy  

PubMed Central

Dynamic force spectroscopy (DFS) makes it possible to investigate specific interactions between two molecules such as ligand-receptor pairs at the single-molecule level. In the DFS method based on the Bell-Evans model, the unbinding force applied to a molecular bond is increased at a constant rate, and the force required to rupture the molecular bond is measured. By analyzing the relationship between the modal rupture force and the logarithm of the loading rate, microscopic potential barrier landscapes and the lifetimes of bonds can be obtained. However, the results obtained, for example, in the case of streptavidin/biotin complexes, have differed among previous studies and some results have been inconsistent with theoretical predictions. In this study, using an atomic force microscopy technique that enables the precise analysis of molecular interactions on the basis of DFS, we investigated the effect of the sampling rate on DFS analysis. The shape of rupture force histograms, for example, was significantly deformed at a sampling rate of 1 kHz in comparison with that of histograms obtained at 100 kHz, indicating the fundamental importance of ensuring suitable experimental conditions for further advances in the DFS method.

Taninaka, Atsushi; Hirano, Yuuichi; Takeuchi, Osamu; Shigekawa, Hidemi

2012-01-01

433

On the critical forcing amplitude of forced nonlinear oscillators  

NASA Astrophysics Data System (ADS)

The steady-state response of forced single degree-of-freedom weakly nonlinear oscillators under primary resonance conditions can exhibit saddle-node bifurcations, jump and hysteresis phenomena, if the amplitude of the excitation exceeds a certain value. This critical value of excitation amplitude or critical forcing amplitude plays an important role in determining the occurrence of saddle-node bifurcations in the frequency-response curve. This work develops an alternative method to determine the critical forcing amplitude for single degree-of-freedom nonlinear oscillators. Based on Lagrange multipliers approach, the proposed method considers the calculation of the critical forcing amplitude as an optimization problem with constraints that are imposed by the existence of locations of vertical tangency. In comparison with the Gröbner basis method, the proposed approach is more straightforward and thus easy to apply for finding the critical forcing amplitude both analytically and numerically. Three examples are given to confirm the validity of the theoretical predictions. The first two present the analytical form for the critical forcing amplitude and the third one is an example of a numerically computed solution.

Febbo, Mariano; Ji, Jinchen C.

2013-08-01

434

[International Education Programs].  

ERIC Educational Resources Information Center

Perspectives concerning the overall process of providing international education are considered in three articles. In "The Development of an International Commitment: A Case Study," Earl L. Backman describes the successful implementation of an international program at the University of North Carolina, Charlotte. The Program for International

Slavin, Gerald M., Ed.; Colahan, Clark A., Ed.

1981-01-01

435

[International Education Programs].  

ERIC Educational Resources Information Center

|Perspectives concerning the overall process of providing international education are considered in three articles. In "The Development of an International Commitment: A Case Study," Earl L. Backman describes the successful implementation of an international program at the University of North Carolina, Charlotte. The Program for International

Slavin, Gerald M., Ed.; Colahan, Clark A., Ed.

1981-01-01

436

A tense situation: forcing tumour progression  

Microsoft Academic Search

Cells within tissues are continuously exposed to physical forces including hydrostatic pressure, shear stress, and compression and tension forces. Cells dynamically adapt to force by modifying their behaviour and remodelling their microenvironment. They also sense these forces through mechanoreceptors and respond by exerting reciprocal actomyosin- and cytoskeletal-dependent cell-generated force by a process termed 'mechanoreciprocity'. Loss of mechanoreciprocity has been shown

Darci T. Butcher; Tamara Alliston; Valerie M. Weaver

2009-01-01

437

Force Measurement Device for ARIANE 5 Payloads  

Microsoft Academic Search

ESTEC uses since 1991 a Force Measurement Device (FMD) for the measurement of dynamic mechanical forces and moments. This tool allows the determination of forces and moments applied to the test hardware at its interface to the test facilities during dynamic testing. Three forces and three moments are calculated from the measurements of eight tri-axial force links and used to

O. Brunner; R. Braeken

2004-01-01

438

Suspending force control scheme for bearingless SRM  

Microsoft Academic Search

This paper presents a novel hybrid pole BLSRM(bearingless switched reluctance motor) and its radial force control scheme. The radial force can be produced by the radial force winding which is wound at separated radial force poles. And the rotating torque is produced by the excitation current of torque windings which are wound at torque pole. The proposed radial force control

Tae-Hub Park; Jianing Liang; Dong-Hee Lee; Huijun Wang; Jin-Woo Ahn

2009-01-01

439

Calibration of lateral force measurements in atomic force microscopy with a piezoresistive force sensor  

NASA Astrophysics Data System (ADS)

We present here a method to calibrate the lateral force in the atomic force microscope. This method makes use of an accurately calibrated force sensor composed of a tipless piezoresistive cantilever and corresponding signal amplifying and processing electronics. Two ways of force loading with different loading points were compared by scanning the top and side edges of the piezoresistive cantilever. Conversion factors between the lateral force and photodiode signal using three types of atomic force microscope cantilevers with rectangular geometries (normal spring constants from 0.092 to 1.24 N/m and lateral stiffness from 10.34 to 101.06 N/m) were measured in experiments using the proposed method. When used properly, this method calibrates the conversion factors that are accurate to +/-12.4% or better. This standard has less error than the commonly used method based on the cantilever's beam mechanics. Methods such of this allow accurate and direct conversion between lateral forces and photodiode signals without any knowledge of the cantilevers and the laser measuring system.

Xie, Hui; Vitard, Julien; Haliyo, Sinan; Régnier, Stéphane; Boukallel, Mehdi

2008-03-01

440

Workforce Coalition: Education Task Force  

NASA Website

[Educators K-Higher Education] [Available: Nationally] The Workforce Coalition task force will use a systems approach to engage community stakeholders in facilitating partnerships to build skills needed for the workforce.

441

Air Force Research Objectives, 1968.  

National Technical Information Service (NTIS)

The Office of Aerospace Research (OAR), as the prime research agency of the United States Air Force, conducts research within its own laboratories and, through its grants and contracts program, sponsors scientific research among the leading scientists of ...

1968-01-01

442

Physlet Force Concept Inventory: Gravity  

NSDL National Science Digital Library

A boy throws a steel ball straight up. Consider the motion of the ball only after it has left the boy's hand but before it touches the ground, and assume that the forces exerted by the air are negligible.

Christian, Wolfgang; Belloni, Mario

2006-01-13

443

Triggering enzymatic activity with force.  

PubMed

Integrating single molecule force spectroscopy with fluorescence-based techniques allows the manipulation of an enzyme with a periodic stretching and relaxation protocol while simultaneously monitoring its catalytic activity. After releasing the stretching force we observe a higher probability for enzymatic activity at a time of 1.7 s. A detailed theoretical analysis reveals that the relaxation from the force-induced enzyme conformation to the observed active conformation follows a cascade reaction with several steps and a free energy difference of at least 8 k(B)T. Our study clearly points out the direct influence of force on enzymatic activity and opens up a new way to study and manipulate (bio)catalytic reactions at the single molecule level. PMID:19658405

Gumpp, Hermann; Puchner, Elias M; Zimmermann, Julia L; Gerland, Ulrich; Gaub, Hermann E; Blank, Kerstin

2009-09-01

444

Investigating Forces: Balloon car activity  

NSDL National Science Digital Library

This is a guided inquiry-based lab that investigates forces exerted on a group of student-designed and engineered "balloon cars". Each group of students is then challenged to build a "balloon car" that travels a maximum distance.

445

Animal welfare and international trade.  

PubMed

Globalisation is becoming a force that is revolutionising international trade, particularly that of animals and animal products. There is increasing interest in animal welfare worldwide, and as part of its 2001-2005 Strategic Plan the World Organisation for Animal Health (OIE) identified the development of international standards on animal welfare as a priority. The OIE's scientific approach to standard-setting provides the foundation for the development, and acceptance by all OIE Member Countries, of these animal welfare guidelines. The paper discusses how these guidelines on animal welfare can be implemented, both within the provisions of World Trade Organization (WTO) agreements and within the framework of voluntary codes of conduct. Even if animal welfare guidelines are not covered by any WTO agreements in the future, bi- and multilateral agreements, voluntary corporate codes, and transparent labelling of products should result in a progressive acceptance of OIE guidelines. Ultimately, consumer demands and demonstrable gains in animal production will result in an incremental evolution in animal welfare consciousness and adherence to international standards. PMID:16358524

Thiermann, A B; Babcock, S

2005-08-01

446

International Comparisons in Education  

NSDL National Science Digital Library

The National Center for Education Statistics (NCES) has recently relaunched and revamped its International Comparisons in Education Website. From this site, visitors can access international comparative education data from major international studies, discover new international projects, and find links to additional resources on international education comparisons and related topics. Project information is listed by topic area: Math and Science, Reading, Civic Education, and Adult Literacy, and each topic page offers background information and further resources.

447

Drag force scaling for penetration into granular media.  

PubMed

Impact dynamics is measured for spherical and cylindrical projectiles of many different densities dropped onto a variety non-cohesive granular media. The results are analyzed in terms of the material-dependent scaling of the inertial and frictional drag contributions to the total stopping force. The inertial drag force scales similar to that in fluids, except that it depends on the internal friction coefficient. The frictional drag force scales as the square-root of the density of granular medium and projectile, and hence cannot be explained by the combination of granular hydrostatic pressure and Coulomb friction law. The combined results provide an explanation for the previously observed penetration depth scaling. PMID:23767531

Katsuragi, Hiroaki; Durian, Douglas J

2013-05-29

448

Energy and spectral dynamics in forced compressible turbulence  

Microsoft Academic Search

Numerical simulations are used to study compressible turbulence with microscale Reynolds numbers up to 40 and rms Mach numbersM up to 0.9. The flows are randomly forced, with energy supplied to either the rotational or compressive components of kinetic energy, which is then transferred to internal energy through the pressure-dilatation interaction and viscous dissipation terms. Coupling between the two components

Shigeo Kida; Steven A. Orszag

1990-01-01

449

Forced motion near black holes  

NASA Astrophysics Data System (ADS)

We present two methods for integrating forced geodesic equations in the Kerr spacetime. The methods can accommodate arbitrary forces. As a test case, we compute inspirals caused by a simple drag force, mimicking motion in the presence of gas. We verify that both methods give the same results for this simple force. We find that drag generally causes eccentricity to increase throughout the inspiral. This is a relativistic effect qualitatively opposite to what is seen in gravitational-radiation-driven inspirals, and similar to what others have observed in hydrodynamic simulations of gaseous binaries. We provide an analytic explanation by deriving the leading order relativistic correction to the Newtonian dynamics. If observed, an increasing eccentricity would thus provide clear evidence that the inspiral was occurring in a nonvacuum environment. Our two methods are especially useful for evolving orbits in the adiabatic regime. Both use the method of osculating orbits, in which each point on the orbit is characterized by the parameters of the geodesic with the same instantaneous position and velocity. Both methods describe the orbit in terms of the geodesic energy, axial angular momentum, Carter constant, azimuthal phase, and two angular variables that increase monotonically and are relativistic generalizations of the eccentric anomaly. The two methods differ in their treatment of the orbital phases and the representation of the force. In the first method, the geodesic phase and phase constant are evolved together as a single orbital phase parameter, and the force is expressed in terms of its components on the Kinnersley orthonormal tetrad. In the second method, the phase constants of the geodesic motion are evolved separately and the force is expressed in terms of its Boyer-Lindquist components. This second approach is a direct generalization of earlier work by Pound and Poisson [A. Pound and E. Poisson, Phys. Rev. DPRVDAQ1550-7998 77, 044013 (2008).10.1103/PhysRevD.77.044013] for planar forces in a Schwarzschild background.

Gair, Jonathan R.; Flanagan, Éanna É.; Drasco, Steve; Hinderer, Tanja; Babak, Stanislav

2011-02-01

450

Forced motion near black holes  

SciTech Connect

We present two methods for integrating forced geodesic equations in the Kerr spacetime. The methods can accommodate arbitrary forces. As a test case, we compute inspirals caused by a simple drag force, mimicking motion in the presence of gas. We verify that both methods give the same results for this simple force. We find that drag generally causes eccentricity to increase throughout the inspiral. This is a relativistic effect qualitatively opposite to what is seen in gravitational-radiation-driven inspirals, and similar to what others have observed in hydrodynamic simulations of gaseous binaries. We provide an analytic explanation by deriving the leading order relativistic correction to the Newtonian dynamics. If observed, an increasing eccentricity would thus provide clear evidence that the inspiral was occurring in a nonvacuum environment. Our two methods are especially useful for evolving orbits in the adiabatic regime. Both use the method of osculating orbits, in which each point on the orbit is characterized by the parameters of the geodesic with the same instantaneous position and velocity. Both methods describe the orbit in terms of the geodesic energy, axial angular momentum, Carter constant, azimuthal phase, and two angular variables that increase monotonically and are relativistic generalizations of the eccentric anomaly. The two methods differ in their treatment of the orbital phases and the representation of the force. In the first method, the geodesic phase and phase constant are evolved together as a single orbital phase parameter, and the force is expressed in terms of its components on the Kinnersley orthonormal tetrad. In the second method, the phase constants of the geodesic motion are evolved separately and the force is expressed in terms of its Boyer-Lindquist components. This second approach is a direct generalization of earlier work by Pound and Poisson [A. Pound and E. Poisson, Phys. Rev. D 77, 044013 (2008).] for planar forces in a Schwarzschild background.

Gair, Jonathan R. [Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom); Flanagan, Eanna E. [Center for Radiophysics and Space Research, Cornell University, Ithaca, New York 14853 (United States); Drasco, Steve [Albert-Einstein-Institut, Max-Planck-Institut fuer Gravitationsphysik, D-14476 Golm (Germany); Theoretical Astrophysics, California Institute of Technology, Pasadena, California 91125 (United States); California Polytechnic State University, San Luis Obispo, California 93405 (United States); Hinderer, Tanja [Theoretical Astrophysics, California Institute of Technology, Pasadena, California 91125 (United States); Babak, Stanislav [Albert-Einstein-Institut, Max-Planck-Institut fuer Gravitationsphysik, D-14476 Golm (Germany)

2011-02-15

451

COOLING FORCE MEASUREMENTS IN CELSIUS.  

SciTech Connect

The design of future high energy coolers relies heavily on extending the results of cooling force measurements into new regimes by using simulation codes. In order to carefully benchmark these codes we have accurately measured the longitudinal friction force in CELSIUS by recording the phase shift between the beam and the RF voltage while varying the RF frequency. Moreover, parameter dependencies on the electron current, solenoid magnetic field and magnetic field alignment were carried out.

GALNANDER, B.; FEDOTOV, A.V.; LITVINENKO, V.N.; ET AL.

2005-09-18

452

Restoring Forces on Nematic Disclinations  

Microsoft Academic Search

\\u000a We compute both the force and the torque acting on a nematic disclination of arbitrary shape in space. The disclination’s\\u000a core, where the material is thought of as melted in its isotropic phase, is not necessarily assumed to be a circular cylinder.\\u000a The effect of the core’s shape on the forces restoring equilibrium is also studied in some detail.

R. Rosso; E. G. Virga

453

Physics Classroom: Resolution of Forces  

NSDL National Science Digital Library

This interactive tutorial explains how to resolve a force into force components. Numerous examples are combined with a simple language and informative graphics to provide students with a solid grasp of the method. Several practice problems and a Check Your Understanding section allows students to self-assess their learning. This is part of The Physics Classroom Tutorial series, a set of instructional pages aimed at students looking for a better grasp of basic concepts.

Henderson, Tom

2012-12-15

454

International law and law enforcement firearms.  

PubMed

Several international agreements set constraints on the legitimate use of firearms as representing lethal force. Their meaning in terms of weapons technology must take into account their operational frame of reference, and legitimate warfare can be regarded as a law enforcement operation with similar principles on the use of force. Changes in weapons technology, such as new types of ammunition, transforming firearms into weapons with less-lethal and even humanitarian options, require new interpretations of the legislation. A division into lethal and non-lethal weapons is an oversimplification and the separation of international humanitarian law into military and law enforcement provisions can be questioned from the technical aspect. The type of technology acceptable for law enforcement use of firearms should be defined. An assessment for weapon injury should not be based on lethality, but rather on the potential for tissue damage and its reversibility. PMID:15015547

Jussila, Jorma; Normia, Pertti

455

Electrostatic force on saltating sand  

NASA Astrophysics Data System (ADS)

In blizzards and sandstorms, wind transport of particles is associated with separation of electrostatic charge. Moving particles develop charge of sign opposite the electrostatic charge on stationary surface particles. This electrification produces forces in addition to the gravitational and fluid friction forces that determine trajectories for particles being transported in saltation. Evaluating electrostatic forces requires the electric field strength very near the saltation surface and charge-to-mass ratios for the moving particles. In a low-level blowing sand event we measured an average charge-to-mass ratio of +60 ?C kg-1 on the saltating particles at 5-cm height and a maximum electric field of +166 kV m-1 at 1.7-cm height, in wind gusts near 12 m s-1 at 1.5-m height. The electrostatic force estimated from these measurements was equal in magnitude to the gravitational force on the saltating particles. Including electrostatic forces in the equations of motion for saltating particles may help explain discrepancies between measurements and models of saltation transport.

Schmidt, D. S.; Schmidt, R. A.; Dent, J. D.

1998-04-01

456

Modifying landing mat material properties may decrease peak contact forces but increase forefoot forces in gymnastics landings  

Microsoft Academic Search

This study investigated how changes in the material properties of a landing mat could minimise ground reaction forces (GRF) and internal loading on a gymnast during landing. A multi-layer model of a gymnastics competition landing mat and a subject-specific seven-link wobbling mass model of a gymnast were developed to address this aim. Landing mat properties (stiffness and damping) were optimised

Chris Mills; Maurice R. Yeadon; Matthew T. G. Pain

2010-01-01

457

Oil spills: International problem requires international solution  

Microsoft Academic Search

Oil spills are an international problem which requires international solutions. The forum where tanker safety issues are fought is the United Nations-affiliated Intergovernmental Maritime Consultative Organization (IMCO). IMCO has over 100 members but is dominated by the dozen or so top maritime powers. It was established in 1954 to prevent oil pollution, but up to 1978 its numerous accords on

Kemezis

1978-01-01

458

Canadian Forces Addictions Awareness and Prevention Strategy.  

National Technical Information Service (NTIS)

In 2002, as part of the restructuring to improve health care delivery in the Canadian Forces (CF), the health promotion program, Strengthening the Forces (STF), was enhanced within the CF Health Services Directorate of Force Health Protection (DFHP) which...

D. Brothers D. Chafe

2011-01-01

459

Dynamic Force Measurement: Instrumented Charpy Impact Testing.  

National Technical Information Service (NTIS)

Maximum forces and forces at general yield measured on impact reference materials in round robin testing are reported. These dynamic results are compared with static force calibration of instrumented strikers. One machine in the round robin was identified...

C. N. McCowan E. Lucon J. D. Splett

2008-01-01

460

Establishing a Communications Officer Force Development Program.  

National Technical Information Service (NTIS)

Senior Air Force leaders tout its Airmen as its most important asset. Nonetheless, Airmen take a back seat to acquisition programs, Battle Dress Uniform redesigns, and fitness uniform procurement. In 2003, the Air Force launched the force development prog...

B. J. Jenrette

2006-01-01

461

The Future of General Internal Medicine  

PubMed Central

The Society of General Internal Medicine asked a task force to redefine the domain of general internal medicine. The task force believes that the chaos and dysfunction that characterize today's medical care, and the challenges facing general internal medicine, should spur innovation. These are our recommendations: while remaining true to its core values and competencies, general internal medicine should stay both broad and deep—ranging from uncomplicated primary care to continuous care of patients with multiple, complex, chronic diseases. Postgraduate and continuing education should develop mastery. Wherever they practice, general internists should be able to lead teams and be responsible for the care their teams give, embrace changes in information systems, and aim to provide most of the care their patients require. Current financing of physician services, especially fee-for-service, must be changed to recognize the value of services performed outside the traditional face-to-face visit and give practitioners incentives to improve quality and efficiency, and provide comprehensive, ongoing care. General internal medicine residency training should be reformed to provide both broad and deep medical knowledge, as well as mastery of informatics, management, and team leadership. General internal medicine residents should have options to tailor their final 1 to 2 years to fit their practice goals, often earning a certificate of added qualification (CAQ) in special generalist fields. Research will expand to include practice and operations management, developing more effective shared decision making and transparent medical records, and promoting the close personal connection that both doctors and patients want. We believe these changes constitute a paradigm shift that can benefit patients and the public and reenergize general internal medicine.

Larson, Eric B; Fihn, Stephan D; Kirk, Lynne M; Levin, Wendy; Loge, Ronald V; Reynolds, Eileen; Sandy, Lewis; Schroeder, Steven; Wenger, Neil; Williams, Mark

2004-01-01

462

Antibacterial Drug Development Task Force Members  

Center for Drug Evaluation (CDER)

... Antibacterial Drug Development Task Force Members. Name, Office/Division, Task Force Role, Title. Edward Cox, Office of ... More results from www.fda.gov/drugs/developmentapprovalprocess/developmentresources

463

Perspective on One Decade of Laser Propulsion Research at the Air Force Research Laboratory, November 1995-2005 (DVD).  

National Technical Information Service (NTIS)

A short film and presentation on laser propulsion research at the Air Force Research Laboratory, spanning November 1995 through October 2005. Presented at the 5th International Symposium on Beamed Energy Propulsion (ISBEP 5), Keauhou Beach, Hawaii, 12-15 ...

2007-01-01

464

75 FR 34438 - Defense Science Board Task Force on Trends and Implications of Climate Change for National and...  

Federal Register 2010, 2011, 2012, 2013

The Defense Science Board Task Force on Trends and Implications of Climate Change for National and International Security will meet in closed session on July 14-15 and on July 29-30, 2010, in Arlington,...

2010-06-17

465

75 FR 43944 - Defense Science Board; Task Force on Trends and Implications of Climate Change for National and...  

Federal Register 2010, 2011, 2012, 2013

The Defense Science Board Task Force on Trends and Implications of Climate Change for National and International Security will meet in closed session August 18-19, and September 20-21, 2010, in Arlington,...

2010-07-27

466

The degeneration of internal waves in lakes with sloping topography  

Microsoft Academic Search

In a laboratory study, we quantified the temporal energy flux associated with the degeneration of basin-scale internal waves in closed basins. The system is two-layer stratified and subjected to a single forcing event creating available potential energy at time zero. A downscale energy transfer was observed from the wind-forced basin-scale motions to the turbulent motions, where energy was lost due

L. Boegman; G. N. Ivey; J. Imberger

2005-01-01

467

Note: Helical nanobelt force sensors  

SciTech Connect

We present the fabrication and characterization of helical nanobelt force sensors. These self-sensing force sensors are based on the giant piezoresistivity of helical nanobelts. The three-dimensional helical nanobelts are self-formed from 27 nm-thick n-type InGaAs/GaAs bilayers using rolled-up techniques, and assembled onto electrodes on a micropipette using nanorobotic manipulations. The helical nanobelt force sensors can be calibrated using a calibrated atomic force microscope cantilever system under scanning electron microscope. Thanks to their giant piezoresistance coefficient (515 Multiplication-Sign 10{sup -10} Pa{sup -1}), low stiffness (0.03125 N/m), large-displacement capability ({approx}10 {mu}m), and good fatigue resistance, they are well suited to function as stand-alone, compact ({approx}20 {mu}m without the plug-in support), light ({approx}5 g including the plug-in support), versatile and large range ({approx}{mu}N) and high resolution ({approx}nN) force sensors.

Hwang, G. [Laboratory for Photonics and Nanostructures, Centre National de la Recherche Scientifique, Marcoussis 91460 (France); Hashimoto, H. [Department of EECE, Chuo University 1-13-27 Kasuga, Bunkyo-ku, Tokyo (Japan)

2012-12-15

468

The experience of force: the role of haptic experience of forces in visual perception of object motion and interactions, mental simulation, and motion-related judgments.  

PubMed

Forces are experienced in actions on objects. The mechanoreceptor system is stimulated by proximal forces in interactions with objects, and experiences of force occur in a context of information yielded by other sensory modalities, principally vision. These experiences are registered and stored as episodic traces in the brain. These stored representations are involved in generating visual impressions of forces and causality in object motion and interactions. Kinematic information provided by vision is matched to kinematic features of stored representations, and the information about forces and causality in those representations then forms part of the perceptual interpretation. I apply this account to the perception of interactions between objects and to motions of objects that do not have perceived external causes, in which motion tends to be perceptually interpreted as biological or internally caused. I also apply it to internal simulations of events involving mental imagery, such as mental rotation, trajectory extrapolation and judgment, visual memory for the location of moving objects, and the learning of perceptual judgments and motor skills. Simulations support more accurate judgments when they represent the underlying dynamics of the event simulated. Mechanoreception gives us whatever limited ability we have to perceive interactions and object motions in terms of forces and resistances; it supports our practical interventions on objects by enabling us to generate simulations that are guided by inferences about forces and resistances, and it helps us learn novel, visually based judgments about object behavior. PMID:22730922

White, Peter A

2012-07-01

469

MR compatible strain gauge based force transducer.  

PubMed

In order to evaluate brain activation during motor tasks accurately one must also measure output parameters such as muscle force or muscle activity. Especially in clinical situations where the force output can be compromised by changes at different levels of the motor system, it is essential to standardize the task or force level. We have therefore developed a magnetic resonance compatible force transducer that is capable of recording index finger abduction force and to display the produced force in real-time. This transducer is based on strain-gauges techniques and designed to measure both small and large forces accurately (range 0.7-60N) as well as fast force fluctuations. Experiments showed that the MR environment did not affect the force measurements or vice versa. Although, this transducer is developed for measuring index finger forces, detailed schematic diagrams are provided such that the transducer can easily be adapted for measuring forces of other muscle groups. PMID:17604114

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

2007-05-10

470

Sensorimotor memory and grip force control: does grip force anticipate a self-produced weight change when drinking with a straw from a cup?  

PubMed

We examined whether self-generated weight changes are anticipated by adequate grip force adjustments when repeatedly lifting an instrumented manipulandum. Subjects lifted a cup filled with 500 mL of water prior to and following drinking two portions of water with a straw without touching it. One half of the subjects drank from and lifted an uncovered cup receiving constant visual information about its filling level and the other half of the subjects drank from a covered cup without such visual feedback. During the lifts immediately following the drinking procedures, grip force scaling was erroneously programmed for the heavier weight of the preceding lift as was obvious from an inadequately high rate of grip force development. Vision had only a minor influence on the rate of grip force increase. The influence of vision on the scaling of peak grip force was more pronounced. More accurate force scaling was obtained with an increasing number of lifts performed under each weight condition, indicating an ongoing force adjustment process probably based on sensory feedback. We conclude that self-generation of a change in the weight of an object to be lifted is not, in itself, sufficient to elicit a predictive grip force output. Rather, accurate feedback information associated with the self-generated weight change is essential to update internal models related to the mechanical object properties. This assumption was confirmed in pilot experiments; when subjects lifted the cup after having poured water from it, they accurately scaled their fingertip force to the self-produced weight change. Here, direct sensory feedback from the grasping fingers could signal the weight change and update internal models while pouring water from the cup. Our data support the hypothesis that the sensorimotor system planning and processing predictive fingertip force can operate independently of higher-level cognitive and perceptual systems. PMID:14656338

Nowak, Dennis A; Hermsdörfer, Joachim

2003-11-01

471

Internal Audit Manual.  

National Technical Information Service (NTIS)

The manual establishes uniform policies and procedures to aid DoD auditors and internal audit and internal review organizations comply with standards, policies, and procedures promulgated by the Congress, the Comptroller General of the United States, the ...

C. Rawdon

1986-01-01

472

International Osteoporosis Foundation  

MedlinePLUS

IOF International IOF Websites IOF International IOF Middle East and Africa IOF Latin America Member Societies - Algeria - Argentina - Armenia - Australia - Austria - Bahrain - Belarus - Belgium - Bolivia - Bosnia and Herzegovina - Brazil - Bulgaria - Canada - Chile - ...

473

International petroleum statistics report.  

National Technical Information Service (NTIS)

The International Petroleum Statistic Report, a monthly publication, presents data on international oil production, demand, imports, exports, and stocks. The four sections of this April 1995 report are as follows: time series data on world oil production ...

1995-01-01

474

International Telecommunications Bibliography.  

National Technical Information Service (NTIS)

The annotated bibliography covers international telecommunications, concentrating on reports with possible policy implications for the Office of Telecommunications Policy and other government/industry agencies. Since the scope of international telecommuni...

M. P. Fackelman K. A. Krekel

1976-01-01

475

International Association of Geodesy  

NSDL National Science Digital Library

The International Association of Geodesy (IAG), one of seven associations within the International Union of Geodesy and Geophysics (IUGG), provides links to publications, meeting announcements, training, membership, and news articles.

476

International Dyslexia Association  

MedlinePLUS

The International Dyslexia Association (IDA) is the recipient of the "Best in America" seal from Independent Charities of America, a distinction ... donations of our many supporters. Welcome! The International Dyslexia Association (IDA) is a non-profit organization dedicated ...

477

Note on forced Burgers turbulence  

SciTech Connect

A putative powerlaw range of the probability density of velocity gradient in high-Reynolds-number forced Burgers turbulence is studied. In the absence of information about shock locations, elementary conservation and stationarity relations imply that the exponent {minus}{alpha} in this range satisfies {alpha}{ge}3, if dissipation within the power-law range is due to isolated shocks. A generalized model of shock birth and growth implies {alpha}=7/2 if initial data and forcing are spatially homogeneous and obey Gaussian statistics. Arbitrary values {alpha}{ge}3 can be realized by suitably constructed homogeneous, non-Gaussian initial data and forcing. {copyright} {ital 1999 American Institute of Physics.}

Kraichnan, R.H. [PMB 108, 369 Montezuma, Santa Fe, New Mexico 87501-2626 (United States)

1999-12-01

478

Forces in nematic liquid crystals: from nanoscale interfacial forces to long-range forces in nematic colloids  

Microsoft Academic Search

In this paper we give an overview of experiments that provided an insight into the nature of forces between surfaces and objects in a nematic liquid crystal. These forces, also called ‘structural forces’, are the consequence of the long-range orientational order and orientational elasticity of nematic liquid crystals. Owing to their fundamental as well as technological importance, forces between objects

Igor Muševi?

2009-01-01

479

Future Force Warrior: Insights from Air Assault Expeditionary Force Assessment.  

National Technical Information Service (NTIS)

Future Force Warrior (FFW) Soldier ensembles were evaluated in 2006. One 9-man squad of infantry Soldiers was equipped with the Soldier or Leader variation of the FFW system. Each system included the FFW uniform and helmet, body armor chassis, global posi...

C. B. Carstens D. D. Turner

2007-01-01

480

Calibration of acoustic trapping forces by fluid drag forces  

Microsoft Academic Search

A transverse acoustic trapping was experimentally demonstrated in a similar manner to optical tweezers. With its relatively simple scheme and low intensity, a single beam ultrasound was used to laterally manipulate lipid droplets underneath a thin mylar membrane. The droplets were directed towards the beam focus, within the range of hundreds of micrometers. Acoustic trapping forces acted on the droplets

Jungwoo Lee; Changyang Lee; K. Kirk Shung

2009-01-01

481

Simulation of a force-on-force exercise  

SciTech Connect

The Security Exercise Evaluation System (SEES) is under development for use in planning force-on-force exercises and as an aid in post- exercise evaluation. SEES is an event-driven, stochastic computer program that simulates individual movement and combat within an urban terrain environment. The simulator models the physics of movement, line of sight, and weapon effects. It relies on controllers to provide all knowledge of security tactics, which are entered by controllers during the simulation using interactive color-graphic workstations. They are able to develop, modify and implement plans promptly as the simulator maintains real time. In this article, we describe how SEES is used to develop an intrusion plan, test the security response tactics, and develop observer logistics. A force-on-force field exercise is then executed to follow the plan and record observations. Finally, the model is analyzed by comparing the plan and events of the simulation with the field exercise, modifying the simulation plan to match the actual field exercise, and then running the simulation to develop a distribution of possible outcomes. 1 ref., 5 figs.

Terhune, R.; Van Slyke, D.; Sheppard, T.; Brandrup, M.

1988-07-10

482

Force generation in RNA polymerase.  

PubMed Central

RNA polymerase (RNAP) is a processive molecular motor capable of generating forces of 25-30 pN, far in excess of any other known ATPase. This force derives from the hydrolysis free energy of nucleotides as they are incorporated into the growing RNA chain. The velocity of procession is limited by the rate of pyrophosphate release. Here we demonstrate how nucleotide triphosphate binding free energy can rectify the diffusion of RNAP, and show that this is sufficient to account for the quantitative features of the measured load-velocity curve. Predictions are made for the effect of changing pyrophosphate and nucleotide concentrations and for the statistical behavior of the system.

Wang, H Y; Elston, T; Mogilner, A; Oster, G

1998-01-01

483

Illinois PER Interactive Examples: Forces  

NSDL National Science Digital Library

This is an interactive homework problem for introductory physics students relating to vector addition. Given a free-body diagram depicting three forces acting on an object, students are required to find the magnitude of the net force. A user-activated "help" sequence is provided for each step of the problem-solving, from conceptual analysis through quantitative calculation. To promote critical thinking, immediate feedback is received for both correct and incorrect responses. This item is part of a larger collection of interactive homework problems for introductory physics.

Gladding, Gary

2008-09-12

484

The Forces Behind Cell Movement  

PubMed Central

Cell movement is a complex phenomenon primarily driven by the actin network beneath the cell membrane, and can be divided into three general components: protrusion of the leading edge of the cell, adhesion of the leading edge and deadhesion at the cell body and rear, and cytoskeletal contraction to pull the cell forward. Each of these steps is driven by physical forces generated by unique segments of the cytoskeleton. This review examines the specific physics underlying these phases of cell movement and the origins of the forces that drive locomotion.

Ananthakrishnan, Revathi; Ehrlicher, Allen

2007-01-01

485

Publishing International Counseling Articles  

ERIC Educational Resources Information Center

|This article begins with a rationale for including international articles in the "Journal of Counseling & Development." Then, 2 general categories of international articles are described. First are articles that provide a general overview of counseling in a particular country. The 2nd category is more general and might involve international

Hohenshil, Thomas H.; Amundson, Norman E.

2011-01-01

486

Unit III: International Conflict.  

ERIC Educational Resources Information Center

|This lesson helps students understand the global network involved in international events. Students have an opportunity to examine the impact of internatio