Effects of Control Stick Parameters on Human Controller Response

A fixed base laboratory tracking study was conducted to determine the effects of stick displacement and stick force characteristics on human tracking performance. Three different levels of control stick force/displacement characteristics and stick electrical gain were varied to observe their influence on RMS (Root Mean Square) tracking error and RMS control activity (stick output). The results indicated that both RMS tracking error and RMS control activity were influenced by the three different levels of control stick force/displacement characteristics and stick electrical gain. The human neuromotor time constant was affected by the electrical control gain of the stick while the spring stiffness of the stick influenced the time delay characteristics of the human response behavior

STRESS-DEPENDENT INTERACTIONS BETWEEN CESIUM AND OTHER MATERIALS. Summary Report, February 15, 1962-February 15, 1963

Metals and alloys germane to thermionic energy converter usage were screened for embrittlement by liquid cesium. Techniques are described for more detailed studies of ceramics and susceptible metals. Definite reductions in tensile ductility were observed for 302 stainless steel and molybdenum. Bend ductility was lowered in titanium, titanium-8 aluminum-4 vanadium alloy, niobium, tantalum, and silver-- copper eutectic solder. Some difficulty in reproducibly wetting samples was evident. Slightly contaminating the cesium with oxygen (or water) was observed to increase cesium wettability. (auth

Quantized adiabatic quantum pumping due to interference

Recent theoretical calculations, demonstrating that quantized charge transfer due to adiabatically modulated potentials in mesoscopic devices can result purely from the interference of the electron wave functions (without invoking electron-electron interactions) are reviewed: (1) A new formula is derived for the pumped charge Q (per period); It reproduces the Brouwer formula without a bias, and also yields the effect of the modulating potential on the Landauer formula in the presence of a bias. (2) For a turnstile geometry, with time-dependent gate voltages V_L(t) and V_R(t), the magnitude and sign of Q are determined by the relative position and orientation of the closed contour traversed by the system in the {V_L-V_R} plane, relative to the transmission resonances in that plane. Integer values of Q (in units of e) are achieved when a transmission peak falls inside the contour, and are given by the winding number of the contour. (3) When the modulating potential is due to surface acoustic waves, Q exhibits a staircase structure, with integer values, reminiscent of experimental observations.Comment: Invited talk, Localization, Tokyo, August 200

Judging Implicit Bias: A National Empirical Study of Judicial Stereotypes

American judges, and especially lifetime-appointed federal judges, are often revered as the pinnacle of objectivity, possessing a deep commitment to fairness, and driven to seek justice as they interpret federal laws and the U.S. Constitution. As these judges struggle with some of the great challenges of the modern legal world, empirical scholars must seek to fully understand the role of implicit bias in judicial decision-making. Research from the field of implicit social cognition has long documented negative implicit biases towards a wide range of group members, some of whom may well be harmed in various ways across the legal system. Unfortunately, legal scholarship, and particularly empirical legal scholarship, has lagged behind in terms of investigating how implicit biases, beyond Black and White, may lead to unfair outcomes in a range of legal areas, including those relevant to judges’ potentially landmark legal decisions. This Article proposes, and then empirically tests, the proposition that even today negative implicit biases may manifest in federal and state judges against even so-called privileged minorities, such as Asian- Americans and Jews. We present the results of an original empirical study we conducted on 239 sitting federal and state judges (including 100 federal district judges representing all Circuits) and consider the ways in which these judicial implicit biases may manifest. The study found that the judges harbored strong to moderate negative implicit stereotypes against Asian-Americans and Jews, while holding favorable implicit stereotypes towards Whites and Christians. These negative stereotypes associate Asians and Jews with immoral traits, such as “greedy,” “dishonest,” and “controlling,” and associate Whites and Christians with moral traits, such as “trustworthy,” “honest,” and “giving.” The study further found that federal district court judges sentenced Jewish defendants to marginally longer prison terms than identical Christian defendants and that implicit bias was likely the cause of the disparity. This Article suggests, and the empirical study supports the claim, that automatic biases and cognitions indeed influence a much broader range of judicial decisions than has previously been considered

The status of the quantum dissipation-fluctuation relation and Langevin equation

I examine the arguments which have been given for quantum fluctuation-dissipation theorems. I distinguish between a weak form of the theorem, which is true under rather general conditions, and a strong form which requires a Langevin equation for its statement. I argue that the latter has not been reliably derived.Comment: 9 page

Theory and astrophysical consequences of a magnetized torus around a rapidly rotating black hole

(Abbrev.) We analyze the topology, lifetime, and emissions of a torus around a black hole formed in hypernovae and black hole-neutron star coalescence. The torus is ab initio uniformly magnetized, represented by two counter oriented current-rings, and develops a state of suspended accretion against a "magnetic wall" around the black hole. Magnetic stability of the torus gives rise to a new fundamental limit EB/Ek<0.1 for the ratio of poloidal magnetic field energy-to-kinetic energy. The lifetime of rapid spin of the black hole is effectively defined by the timescale of dissipation of black hole-spin energy in the horizon, and satisfies T= 40s (MH/7MSun)(R/6MH)^4(0.03MH/MT) for a black hole of mass MH surrounded by a torus of mass MT and radius R. The torus converts a major fraction Egw/Erot=0.1 into gravitational radiation through a finite number of multipole mass-moments, and a smaller fraction into MeV neutrinos and baryon-rich winds. At a source distance of 100Mpc, these emissions over N=2e4 periods give rise to a characteristic strain amplitude \sqrt{N}hchar=6e-21. We argue that torus winds create an open magnetic flux-tube on the black hole, which carries a minor and standard fraction Ej/Erot=1e-3 in baryon-poor outflows to infinity. We identify this baryon poor output of tens of seconds with GRBs with contemporaneous and strongly correlated emissions in gravitational radiation, conceivably at multiple frequencies. Ultimately, this leaves a black hole binary surrounded by a supernova remnant.Comment: To appear in ApJ (44p

Cluster virial expansion for the equation of state of partially ionized hydrogen plasma

We study the contribution of electron-atom interaction to the equation of state for partially ionized hydrogen plasma using the cluster-virial expansion. For the first time, we use the Beth-Uhlenbeck approach to calculate the second virial coefficient for the electron-atom (bound cluster) pair from the corresponding scattering phase-shifts and binding energies. Experimental scattering cross-sections as well as phase-shifts calculated on the basis of different pseudopotential models are used as an input for the Beth-Uhlenbeck formula. By including Pauli blocking and screening in the phase-shift calculation, we generalize the cluster-virial expansion in order to cover also near solid density plasmas. We present results for the electron-atom contribution to the virial expansion and the corresponding equation of state, i.e. pressure, composition, and chemical potential as a function of density and temperature. These results are compared with semi-empirical approaches to the thermodynamics of partially ionized plasmas. Avoiding any ill-founded input quantities, the Beth-Uhlenbeck second virial coefficient for the electron-atom interaction represents a benchmark for other, semi-empirical approaches.Comment: 16 pages, 10 figures, and 5 tables, resubmitted to PR

Operational reliability assessment of the GEOS A spacecraft

Decision theory application to GEOS A spacecraft operational reliability assessmen

Adiabatic transport in nanostructures

A confined system of non-interacting electrons, subject to the combined effect of a time-dependent potential and different external chemical-potentials, is considered. The current flowing through such a system is obtained for arbitrary strengths of the modulating potential, using the adiabatic approximation in an iterative manner. A new formula is derived for the charge pumped through an un-biased system (all external chemical potentials are kept at the same value); It reproduces the Brouwer formula for a two-terminal nanostructure. The formalism presented yields the effect of the chemical potential bias on the pumped charge on one hand, and the modification of the Landauer formula (which gives the current in response to a constant chemical-potential difference) brought about by the modulating potential on the other. Corrections to the adiabatic approximation are derived and discussed.Comment: 8 pages, 2 figure

Women in senior post-graduate medicine career roles in the UK: a qualitative study

Objectives:This qualitative study sought to elicit the views, experiences, career journeys and aspirations of women in senior post-graduate medical education roles to identify steps needed to help support career progression.Design:In-depth semi-structured telephone interviews.Setting:UKParticipants:Purposive sample of 12 women in a variety of senior leadership roles in post-graduate medical education in the UK.Main outcome measures:Self reported motivating influences, factors that helped and hindered progress, key branch points, and key educational factors and social support impacting on participants' career in postgraduate medicine.Results:Respondents often reported that career journeys were serendipitous, rather than planned, formal or well structured. Senior women leaders reported having a high internal locus of control, with very high levels of commitment to the NHS. All reported significant levels of drive, although the majority indicated that they were not ambitious in the sense of a strong drive for money, prestige, recognition or power. They perceived that there was an under-representation of women in senior leadership positions and that high-quality female mentorship was particularly important in redressing this imbalance. Social support, such a spouse or other significant family member, was particularly valued as reaffirming and supporting women’s chosen career ambition. Factors that were considered to have hindered career progression included low self-confidence and self-efficacy, the so-called glass ceiling and perceived self-limiting cultural influences. Factors indirectly linked to gender such as part-time versus working full time were reportedly influential in being overlooked for senior leadership roles. Implications of these findings are discussed in the paper.Conclusion:Social support, mentorship and role modelling are all perceived as highly important in redressing perceived gender imbalances in careers in post-graduate medical education