Bipartite modular multiplication with twice the bit-length of multipliers

This paper presents a new technique to compute 2ℓ-bit bipartite multiplications with ℓ-bit bipartite multiplication units. Low-end devices such as smartcards are usually equipped with crypto-coprocessors for accelerating the heavy computation of modular multiplications; however, security standards such as NIST and EMV have declared extending the bit length of RSA cryptosystem to resist mathematical attacks, making the multiplier quickly outdated. Therefore, the double-size techniques have been studied this decade to extend the life expectancy of such multipliers. This paper proposes new double-size techniques based on the multipliers implementing either classical or Montgomery modular multiplications, or even both simultaneously (bipartite modular multiplication), in which case one can potentially compute modular multiplications twice faster. Furthermore, in order to get a more realistic estimation than the other works, this paper considers not only the cost of the multiplication, but also the cost of the other arithmetic instructions. In our estimation, the proposal provides comparable results for classical multiplier and Montgomery multiplier, and is the only available method for the bipartite multiplier. A preliminary version of this paper was presented at the 12th Australasian Conference on Information Security and Privacy, ACISP’07.     

What all applied psychologists should know about work.

Because of the increasing complexity of work in people's lives and the rapid ways in which work is changing, it is likely that all applied psychologists will need greater content knowledge about work to assist clients with issues related to work choice, entry, and adjustment. This article identifies 5 knowledge domains about work that include important information for applied psychologists. These domains are as follows: (a) economics and politics, (b) work structures, (c) globalization, (d) social factors, and (e) technology. These 5 domains are outlined, as are anticipated future trends in work. The implications of these issues for applied psychologists are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The magneto-electric effect in molten salts—1. Visualization and measurement of the magneto-electric voltage in 1-ethyl-pyridinium bromide; comparison of results in the molten salt at 130 °C and in solutions in water and ethanol

The magneto-electric effect has been studied using 1-ethyl-pyridinium bromide in both the molten state and in solution in water or ethanol. The production of stable, coloured radical cations allows one to observe their movement in the cell. From the results it is possible to establish a relationship between the magneto-electric voltage and the type and behaviour of the electrolyte, to better understand the magneto-electric effect in ionic liquid media and to explain the apparent non-reproducibility of certain results. A Lorentz force causes a deviation in the trajectory of charge carriers. This deviation in current lines produces differences in charge concentration in the cell, particularly between the measurement probes. Thus the physical significance of the observed voltage is different from that of the Hall voltage described for electronic solid conductors.     

Removal of ammonia from air on molybdenum and tungsten oxide modified activated carbons

Microporous coconut-based activated carbon was impregnated with solutions of ammonium metatungstate or ammonium molybdate and then calcined in air in order to convert the salts into their corresponding oxides. The surface of those materials was characterized using adsorption of nitrogen, potentiometric titration, Fourier-transform infrared spectroscopy, X-ray diffraction, and thermal analysis. The results indicated a significant increase in surface acidity related to the presence of tungsten or molybdenum oxides. On the materials obtained, adsorption of ammonia from either dry or moist air was carried out. The oxides distributed on the surface provided Lewis and/or Br?nsted centers for interactions with ammonia molecules or ammonium ions. Water on the surface of carbon or in the gas phase increased the amount of ammonia adsorbed via involvement of Br?nsted-type interactions and/or by leading to the formation of molybdate or tungstate salts on the surface. Although the amount of ammonia adsorbed is closely related to the number of moles of oxides and their acidic centers, the carbon surface also contributes to the adsorption via providing small pores where ammonia can be dissolved in the water film.     

Reactive adsorption of NO2 on copper-based metal-organic framework and graphite oxide/metal-organic framework composites

Composites of a copper-based metal-organic framework (MOF) and graphite oxide (GO) were tested for NO2 adsorption and retention of NO in dry and moist conditions. The samples were analyzed before and after exposure to NO2 by thermal analysis, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction, and adsorption of nitrogen at -196 °C. In dry conditions, the composites exhibit an enhanced NO2 breakthrough capacity compared to MOF and GO separately. This improvement is linked to the increased porosity and the reactive adsorption of NO2 on copper, which leads to the formation of bidentate and monodentate nitrate. Even though less NO2 is adsorbed in moist conditions than in dry ones, the materials are more stable than in dry conditions and the NO retention is enhanced. Water in the challenge gas competes with NO2 to bind to copper, and thus, the number of reactive adsorption sites on which NO2 can be adsorbed/reacted decreases.     

Social support for the bereaved: Recipients' and providers' perspectives on what is helpful.

Interviewed 40 people (mean age 44 yrs) who had lost a spouse and 54 people (mean age 42 yrs) who had lost a child in a motor vehicle accident 4–7 yrs earlier to gather information concerning support attempts from others that were helpful and unhelpful. Support attempts most frequently mentioned as helpful were contact with a similar other and opportunity to express feelings; those most frequently mentioned as unhelpful were giving advice and encouraging recovery. To understand better the unhelpful support attempts, comparisons were made with 100 control Ss' reports of what they would do or say to help a bereaved person. The possibility that unhelpful support attempts occur because people do not know what to say to bereaved persons seems implausible in view of the enlightened responses given by controls. The close correspondence between bereaved Ss' reports of how recovered they felt and control respondents' estimates of how recovered the bereaved would be suggests that unhelpful support attempts are not based on misconceptions about recovery. These findings indicate that factors inherent in the transaction between the bereaved and potential supporters should be addressed in future research concerned with understanding support attempts that fail. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)