Efficient Set Sharing Using ZBDDs

Set sharing is an abstract domain in which each concrete object is represented by the set of local variables from which it might be reachable. It is a useful abstraction to detect parallelism opportunities, since it contains definite information about which variables do not share in memory, i.e., about when the memory regions reachable from those variables are disjoint. Set sharing is a more precise alternative to pair sharing, in which each domain element is a set of all pairs of local variables from which a common object may be reachable. However, the exponential complexity of some set sharing operations has limited its wider application. This work introduces an efficient implementation of the set sharing domain using Zero-suppressed Binary Decision Diagrams (ZBDDs). Because ZBDDs were designed to represent sets of combinations (i.e., sets of sets), they naturally represent elements of the set sharing domain. We show how to synthesize the operations needed in the set sharing transfer functions from basic ZBDD operations. For some of the operations, we devise custom ZBDD algorithms that perform better in practice. We also compare our implementation of the abstract domain with an efficient, compact, bit set-based alternative, and show that the ZBDD version scales better in terms of both memory usage and running time

Human-like interactions prompt people to take a robot’s perspective

The increasing need for human-robot interaction requires not only robots to understand how humans think, but also humans to understand robots. Interestingly, little attention has been given to how humans interpret robots’ behaviors. In this study, we adopted a social mental rotation task and investigated whether socially engaging behaviors could influence how people take a robot’s perspectives. In a real lab, two android robots with neutral appearance sat opposite each other by a table with conflicting perspectives. Before the participant started the experiment, one of the robots behaved more interactively than the other by showing more socially engaging behaviors. Then the participant was required to identify rotated normal or mirrored digits presented inbetween the two robots. Results revealed a significant interactive effect between the digits type (normal; mirrored) and robot type (interactive; noninteractive). When digits were oriented to the interactive robot, we found a larger RT difference between normal and mirrored digits. In general, these findings suggested that robots’ interactive behaviors could influence how people spontaneously consider the robot’s perspective. Future studies may further consider how interactive behaviors can shape human-robot relationships and facilitate human-robot interaction

Tri-layer polymer actuators with variable dimensions

The ability of conducting polymer actuators to convert electrical energy into mechanical energy is influenced by manyfactors ranging from the actuators physical dimensions to the chemical structure of the conducting polymer. In order toutilise these actuators to their full potential, it is necessary to explore and quantify the effect of such factors on theoverall actuator performance. The aim of this study is to investigate the effect of various geometrical characteristics suchas the actuator width and thickness on the performance of tri-layer polypyrrole (PPy) actuators operating in air, asopposed to their predecessors operating in an appropriate electrolyte. For a constant actuator length, the influence of theactuator width is examined for a uniform thickness geometry. Following this study, the influence of a varied thicknessgeometry is examined for the optimised actuator width. The performance of the actuators is quantified by examination ofthe force output, tip displacement, efficiency as a function of electrical power and mechanical power, and time constantfor each actuator geometry. It was found that a width of 4mm gave the greatest overall performance without curlingalong the actuator length (which occurred with widths above 4mm). This curling phenomenon increased the rigidity ofthe actuator, significantly lowering the displacement for low loads. Furthermore, it was discovered that by focussing ahigher thickness of PPy material in certain regions of the actuators length, greater performances in various domainscould be achieved. The experimental results obtained set the foundation for us to synthesize PPy actuators with anoptimised geometry, allowing their performance to reach full potential for many cutting applications

Design and fabrication of module coil as an R&D program for Large Helical Device

A twisted solenoid coil (TOKI-MC) has been designed and fabricated in order to study the mechanical properties of the Large Helical Device (LHD). One of the most important R&D items of the LHD is the mechanical behavior of the helical coils under a large electromagnetic force. The TOKI-MC was wound obliquely on the 3D-machined elliptical bobbin with a maximum torsional rate of 36deg/m at the innermost conductor. The maximum field in the coil is 7.7 T with an operating current of 20 kA, an average current density of 40 A/mm^2, and a stored energy of 11 MJ. The TOKI-MC can simulate the electromagnetic force, conductor torsional rate, magnetic field, operating current, and current density of the LHD superconducting helical coils. The design and test results of the conductor and the design and fabrication of the coil are describe

Effect of Heteroatoms on Field-Induced Slow Magnetic Relaxation of Mononuclear Fe-III (S=5/2) Ions within Polyoxometalates.

In this paper, the synthesis and magnetic properties of mononuclear FeIII-containing polyoxometalates (POMs) with differ- ent types of heteroatoms, TBA7H10[(A-α-XW9O34)2Fe] (IIX, X = Ge, Si; TBA = tetra-n-butylammonium), are reported. In these POMs, mononuclear highly distorted six-coordinate octahedral [FeO6]9− units are sandwiched by two trivacant lacunary units [A-α- XW9O34]10− (X = Ge, Si). These POMs exhibit field-induced slow magnetic relaxation based on the single high-spin FeIII magnetic center (S = 5/2). Combining experiment and ab initio calculations, we investigated the effect of heteroatoms of the lacunary units on the field-induced slow magnetic relaxation of these POMs. By changing the heteroatoms from Si (IISi) to Ge (IIGe), the coordination geometry around the FeIII ion is mildly changed. Concretely, the axial Fe−O bond length in IIGe is shortened compared with that in IISi, and consequently the distortion of the [FeO6]9− unit in IIGe from the ideal octahedral coordination geometry becomes larger Si Ge Si than that in II . The effective demagnetization barrier of II (11.4 K) is slightly larger than that of II (9.2 K). Multireference ab initio calculations predict zero-field splitting parameters in good agreement with experiment. Although the differences in the coordination geometries and magnetic properties of IIGe and IISi are quite small, ab initio calculations indicate subtle changes in the magnetic anisotropy which are in line with the observed magnetic relaxation properties

The time variation of dose rate artificially increased by the Fukushima nuclear crisis

A car-borne survey for dose rate in air was carried out in March and April 2011 along an expressway passing northwest of the Fukushima Dai-ichi Nuclear Power Station which released radionuclides starting after the Great East Japan Earthquake on March 11, 2011, and in an area closer to the Fukushima NPS which is known to have been strongly affected. Dose rates along the expressway, i.e. relatively far from the power station were higher after than before March 11, in some places by several orders of magnitude, implying that there were some additional releases from Fukushima NPS. The maximum dose rate in air within the high level contamination area was 36 μGy h−1, and the estimated maximum cumulative external dose for evacuees who came from Namie Town to evacuation sites (e.g. Fukushima, Koriyama and Nihonmatsu Cities) was 68 mSv. The evacuation is justified from the viewpoint of radiation protection

Characterisation and categorisation of the diversity in viscoelastic vibrational properties between 98 wood types

International audienceContext Increased knowledge on diversity in wood properties would have implications both for fundamental research and for promoting a diversification of uses as material. *Aims The objective is to contribute to overcoming the critical lack of data on the diversity of wood dynamic mechanical/viscoelastic vibrational properties, by testing lesser-known species and categorizing sources of variability. *Methods Air-dry axial specific dynamic modulus of elasticity (E'/γ) and damping coefficient (tanδ) were measured on a wide sampling (1792 specimens) of 98 wood types from 79 species. An experimental device and protocol was designed for conducting systematic (i.e. rapid and reproducible) characterizations. *Results Diversity at the specimens' level corroborates the "standard" relationship between tanδ and E'/γ, which is discussed in terms of orientation of wood elements and of chemical composition. Diversity at the species level is expressed on the basis of results for normal heartwood, with specific gravity (γ) ranging from 0.2 to 1.3. Axial E'/γ ranges from 9 to 32 GPa and tanδ from 4×10-3 to 19×10-3. Properties distribution follows a continuum, but with group characteristics. The lowest values of tanδ are only found in certain tropical hardwoods. Results can also suggest alternative species for musical instruments making

Trends in incidence and mortality of tuberculosis in Japan : a population-based study, 1997–2016

Japan is still a medium-burden tuberculosis (TB) country. We aimed to examine trends in newly notified active TB incidence and TB-related mortality in the last two decades in Japan. This is a population-based study using Japanese Vital Statistics and Japan Tuberculosis Surveillance from 1997 to 2016. We determined active TB incidence and mortality rates (per 100 000 population) by sex, age and disease categories. Joinpoint regression was applied to calculate the annual percentage change (APC) in age-adjusted mortality rates and to identify the years showing significant trend changes. Crude and age-adjusted incidence rates reduced from 33.9 to 13.9 and 37.3 to 11.3 per 100 000 population, respectively. Also, crude and age-adjusted mortality rates reduced from 2.2 to 1.5 and 2.8 to 1.0 per 100 000 population, respectively. Average APC in the incidence and mortality rates showed significant decline both in men (−6.2% and −5.4%, respectively) and women (−5.7% and −4.6%, respectively). Age-specific analysis demonstrated decreases in incidence and mortality rates for every age category, except for the incidence trend in the younger population. Although trends in active TB incidence and mortality rates in Japan have favourably decreased, the rate of decline is far from achieving TB elimination by 2035

Tunneling Desorption of Single Hydrogen on the Surface of Titanium Dioxide

We investigated the reaction mechanism of the desorption of single hydrogen from a titanium dioxide surface excited by the tip of a scanning tunneling microscope (STM). Analysis of the desorption yield, in combination with theoretical calculations, indicates the crucial role played by the applied electric field. Instead of facilitating desorption by reducing the barrier height, the applied electric field causes a reduction in the barrier width, which, when coupled with the electron excitation induced by the STM tip, leads to the tunneling desorption of the hydrogen. A significant reduction in the desorption yield was observed when deuterium was used instead of hydrogen, providing further support for the tunneling-desorption mechanism