Risk Assessment Steeplechase: Hurdles to Becoming a Target Market

Framed in a quadrant model, the data sources that analysts use to predict the performance of core property types for the major metropolitan areas in the United States are reviewed. The hypothesis is that forecasters rely on information from the economic base, the property inventory and financial performance quadrants to generate forecasts. For each core property type, analysts are rather homogeneous in grouping metropolitan areas from best to worst. However, the property type determines what sets of economic, social, inventory and market information are used. The only consistent forecast factor used across all property types appears to be economic growth.

Non-adiabaticity and single-electron transport driven by surface acoustic waves

Single-electron transport driven by surface acoustic waves (SAW) through a narrow constriction, formed in two-dimensional electron gas, is studied theoretically. Due to long-range Coulomb interaction, the tunneling coupling between the electron gas and the moving minimum of the SAW-induced potential rapidly decays with time. As a result, nonadiabaticiy sets a limit for the accuracy of the quantization of acoustoelectric current

Fluidization and Its Applications to Food Processing

This paper is a comprehensive review of the science behind fluidization of food materials, and its applications in food processing. Fluidization is a process by which a bed of particulate materials exhibts fluid -like behaviour as a result of fluid flowing through it. Fluidization can be carried out by liquids or gases and different forms of fluidization occur depending on the type of fluidizing medium and the properties of the particulate material , this can have an important effect on the type of processes that can be carried out using fluidization. Typical food processing applications of fluidization include freezing and cooling , drying, puffing, freeze drying , spray drying, classification and blanching and cooking. These processes involve heat and mass transfer to or from the food material, which can be rapidly achieved from fluidization. Food particles are porous and the intraparticle resistances to heat and mass transfer a re usually much higher than the resistance offered by the fluidizing medium. Hence fluidized beds can also be used to determme intra-particle resistances which can then be used to relate to food structure

Consumers’ responses to front-of-pack labels that vary by interpretive content

Previous research has shown that front-of-pack labels (FoPLs) can assist people to make healthier food choices if they are easy to understand and people are motivated to use them. There is some evidence that FoPLs providing an assessment of a food’s health value (evaluative FoPLs) are easier to use than those providing only numerical information on nutrients (reductive FoPLs). Recently, a new evaluative FoPL (the Health Star Rating (HSR)) has been introduced to Australia and New Zealand. The HSR features a summary indicator, differentiating it from many other FoPLs being used around the world. The aim of this study was to understand how consumers of all ages use and make sense of reductive FoPLs and evaluative FoPLs including evaluative FoPLs with and without summary indicators. Ten focus groups were conducted in Perth, Western Australia with adults (n=50) and children aged 10-17 years (n=35) to explore reactions to one reductive FoPL (the Daily Intake Guide), an existing evaluative FoPL (multiple traffic lights), and a new evaluative FoPL (the HSR). Participants preferred the evaluative FoPLs over the reductive FoPL, with the strongest preference being for the FoPL with the summary indicator (HSR). Discussions revealed the cognitive strategies used when interpreting each FoPL (e.g., using cut offs, heuristics, and the process of elimination), which differed according to FoPL format. Most participants reported being motivated to use the evaluative FoPLs (particularly the HSR) to make choices about foods consumed as part of regular daily meals, but not for discretionary foods consumed as snacks or deserts. The findings provide further evidence of the potential utility of evaluative FoPLs in supporting healthy food choices and can assist policy makers in selecting between alternative FoPL formats

The Information Precision of CBD Office Vacancy Rates

Consistent with the rational expectations information model (REIM), the difference among reported area CBD office vacancy rates is proportional to the level of vacancy, inversely proportional to the size of the inventory, and significantly higher when both a national vendor and a local agent make simultaneous reports. Underlying volatility in the market and the cost and difficulty of acquiring information are the principal causes of the information variance. The difficulties and ambiguities in obtaining information are reviewed and the Diamond REIM model is tested using encountered published vacancy rates for central business districts for the period 1985-1989.

Quantized charge transport through a static quantum dot using a surface acoustic wave

We present a detailed study of the surface acoustic wave mediated quantized transport of electrons through a split gate device containing an impurity potential defined quantum dot within the split gate channel. A new regime of quantized transport is observed at low RF powers where the surface acoustic wave amplitude is comparable to the quantum dot charging energy. In this regime resonant transport through the single-electron dot state occurs which we interpret as turnstile-like operation in which the traveling wave amplitude modulates the entrance and exit barriers of the quantum dot in a cyclic fashion at GHz frequencies. For high RF powers, where the amplitude of the surface acoustic wave is much larger than the quantum dot energies, the quantized acoustoelectric current transport shows behavior consistent with previously reported results. However, in this regime, the number of quantized current plateaus observed and the plateau widths are determined by the properties of the quantum dot, demonstrating that the microscopic detail of the potential landscape in the split gate channel has a profound influence on the quantized acoustoelectric current transport.Comment: 9 page

Single-electron transport driven by surface acoustic waves: moving quantum dots versus short barriers

We have investigated the response of the acoustoelectric current driven by a surface-acoustic wave through a quantum point contact in the closed-channel regime. Under proper conditions, the current develops plateaus at integer multiples of ef when the frequency f of the surface-acoustic wave or the gate voltage Vg of the point contact is varied. A pronounced 1.1 MHz beat period of the current indicates that the interference of the surface-acoustic wave with reflected waves matters. This is supported by the results obtained after a second independent beam of surface-acoustic wave was added, traveling in opposite direction. We have found that two sub-intervals can be distinguished within the 1.1 MHz modulation period, where two different sets of plateaus dominate the acoustoelectric-current versus gate-voltage characteristics. In some cases, both types of quantized steps appeared simultaneously, though at different current values, as if they were superposed on each other. Their presence could result from two independent quantization mechanisms for the acoustoelectric current. We point out that short potential barriers determining the properties of our nominally long constrictions could lead to an additional quantization mechanism, independent from those described in the standard model of 'moving quantum dots'.Comment: 25 pages, 12 figures, to be published in a special issue of J. Low Temp. Phys. in honour of Prof. F. Pobel

New advances in Raman study of polyvinylchloride structure

In this work we investigated Raman spectra of a number of industrial grades of polyvinylchloride powder and films, prepared from solutions in tetrahydrofuran and acetophenone. The number and spectral characteristics of the Raman lines in the spectral regions of the C-Cl stretching vibrations and in the region of the C-H and CH2 stretching vibrations were evaluated

Weiss Oscillations in Surface Acoustic Wave Propagation

The interaction of a surface acoustic wave (SAW) with a a two-dimensional electron gas in a periodic electric potential and a classical magnetic field is considered. We calculate the attenuation of the SAW and its velocity change and show that these quantities exhibit Weiss oscillations.Comment: 4 pages REVTEX, 2 figures included as eps file

Quantized Adiabatic Charge Transport in a Carbon Nanotube

The coupling of a metallic Carbon nanotube to a surface acoustic wave (SAW) is proposed as a vehicle to realize quantized adiabatic charge transport in a Luttinger liquid system. We demonstrate that electron backscattering by a periodic SAW potential, which results in miniband formation, can be achieved at energies near the Fermi level. Electron interaction, treated in a Luttinger liquid framework, is shown to enhance minigaps and thereby improve current quantization. Quantized SAW induced current, as a function of electron density, changes sign at half-filling.Comment: 5 pages, 2 figure