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In recent years, the improvement of cloud computing and mobile computing techniques has led to the availability of a variety of mobile applications (‘apps’) in the app store. For instance, a garbage truck app that can provide the immediate location of a garbage truck, the location of collection points, and forecasted arrival times of garbage trucks would be useful for mobile users. Since the power consumption of apps on mobile devices if of concern to mobile users, an optimised power-saving mechanism for updating messages, which is based on location information, for a proposed garbage truck fleet management system (GTFMS) is proposed and implemented in this paper. The GTFMS is a three- component system that includes the on-board units on garbage trucks, a fleet management system, and a garbage truck app. In this study, an arrival time forecasting method is designed and implemented in the fleet management system, so that the garbage truck app can retrieve the forecasted arrival time via web services. A message updating event is then triggered that reports the location of garbage truck and the forecasted arrival time. In experiments conducted on case studies, the results showed that the mean accuracy of predicted arrival time by the proposed method is about 81.45 per cent. As for power consumption, the cost of traditional mobile apps is 2,880 times that of the mechanism proposed in this study. Consequently, the GTFMS can provide the precise forecasted arrival time of garbage trucks to mobile users, while consuming less power.

This work is a study of phase transformation in (001)-cut Pb(Fe1/2Nb1/2)1-xTixO3 (x=48%) single crystals by means of dielectric permittivity, domain structure, and in situ x-ray diffraction. A first-order T(TNT)-C(TNT) phase transition was observed at the Curie temperature TC≅518 K upon zero-field heating. T, TNT, and C are tetragonal, tetragonal nanotwin, and cubic phases, respectively. T(TNT) and C(TNT) indicate that minor TNT domains reside in the T and C matrices. Nanotwins, which can cause broad diffraction peak, remain above TC≅518 K and give an average microscopic cubic symmetry in the polarizing microscopy. Colossal dielectric permittivity (>104) was observed above room temperature with strong frequency dispersion. This study suggests that nanotwins can play an important role in relaxor ferroelectric crystals while phase transition takes place. The Fe ion is a potential candidate as a B-site dopant for enhancing dielectric permittivity. [ABSTRACT FROM AUTHOR]

This work is a study of the thermal stability of (001)-cut Pb(Mg1/3Nb2/3)1-xTixO3 (x=0.30) single crystals before and after an electric (E)-field poling by means of dielectric permittivity, hysteresis loop, domain structure, polarization current, and x-ray diffraction. An R(RNT)-R(RNT)/T(TNT)-T(TNT)-C transition sequence was observed upon heating in the unpoled sample. R, RNT, T, TNT, and C are the rhombohedral, rhombohedral nanotwin, tetragonal, tetragonal nanotwin, and cubic phases, respectively. R/T indicates coexistence of the R and T phases. R(RNT) and T(TNT) indicate that the RNT and TNT structures mimic monoclinic phases in the R and T matrices, respectively. After a prior E-field poling, an R(RNT)-T(TNT)-C phase sequence takes place upon heating. The dielectric permittivity and current density evidenced an additional polarization at 355 K, which is associated with the vanishing of the dielectric dispersion, which reappears near 410 K and remains up to the Burns temperature TB=510 K. This study suggests that nanotwins (RNT and TNT) can play an important role in high-strain piezoelectric crystals while phase transition takes place. Under E=38 kV/cm, [001] T domains randomly appeared in the matrix, suggesting that the matrix consists of a glassy matrix and ferroelectric nanoclusters. [ABSTRACT FROM AUTHOR]

The dielectric permittivity, domain structure, and in situ x-ray diffraction techniques are used to study the phase transformation in (001)-cut Pb[([Fe.sub.1/2][Nb.sub.1/2]).sub.1-x][Ti.sub.x[O.sub.3] (x=48%) single crystals. The results provide insight into the significant role of nanotwins in relaxor ferroelectric crystals during phase transition and the Fe ion as potential candidate at a B-site dopant for enhancing dielectric permittivity.

The thermal stability of (001)-cut Pb[([Mg.sub.1/3][Nb.sub.2/3]).sub.1-x][Ti.sub.x][O.sub.3] (x = 0.30) single crystals before and after an electric (E)-field poling is analyzed by using dielectric permittivity, hysteresis loop, domain structure, polarization current and x-ray diffraction. The study has shown that nanotwins have played a vital role in high-strain piezoelectric crystals while phase transition has taken place.

This study aims to develop an approach which integrates the concept of climate-sensitive design with housing community design for the design of better residential buildings fitting into local wind environment. Employing research methods involving field investigation and computational fluid dynamics (CFD) simulation, the ventilation environment of four typical community atrium spaces were examined and compared in this study. Through a combination of CFD simulation and scenario-based design studies, the research results reveal that the typical long-shape building blocks with high-density housing development lead to poor natural ventilation in atrium open spaces. The research also indicates that if the openings of building masses and atrium can match the prevailing wind direction, the ventilation in community atrium open spaces will be significantly improved, but the overall effects are also affected by several design factors such as the distance between buildings, the size and shape of urban blocks, organization of building masses, and whether or not the wind corridor effect is effectively utilized. It is suggested for further research that more detailed issued-based CFD simulations (e.g., various land use controls or user preferences) of the relationship between wind environment and various design strategies should be conducted in the early stage of the entire design process to obtain the improvement in ventilation environments. [ABSTRACT FROM AUTHOR]

To find a sustainable living environment, ancestors looked to the site selection method of traditional Feng Shui from ancient China, evaluating and selecting the place most suitable to live in. The current location, environmental conditions, and building clusters of the Hua Zhai Settlement meet the most fundamental criteria of site selection. Further analysis of the local weather data from the last thirty years highlighted the most significant weather factor impacting Hua Zhai Settlement: wind. This factor is used in Computational Fluid Dynamics (CFD) wind environmental simulation, the results of which show that settlements that adhere to the most basic site selection principles are able to provide residents with a more comfortable living environment, allowing people to live sustainably. This proves that Feng Shui is indeed the accumulation of rules governing our living experiences. [ABSTRACT FROM AUTHOR]

The gas solubility of pure oxygen and of pure carbon dioxide as well as of their gaseous mixture are measured in the ternary liquid mixture cyclohexane + cyclohexanone + cyclohexanol at 313.6 K with a high-pressure view-cell technique using the synthetic method. The new experimental data are used to assess the capability of molecular simulation and conductor-like screening model (COSMO)-SAC to predict multicomponent fluid-phase coexistence behavior. These methods are also compared systematically on the basis of experimental binary fluid-phase coexistence data. In that comparison also the Peng-Robinson (PR) equation of state is included as a reference. Molecular simulation and COSMO-SAC yield good results and are found to be far superior to the PR equation of state both in predictive and in adjusted mode. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2236-2250, 2013 [ABSTRACT FROM AUTHOR]

This paper tests the arguments put forth by Morgan (2004) and several others that the CRACK/Project Prevention programme, which offers substance-abusing women a monetary incentive to choose long-term or permanent birth control, is racist and unethical. Findings from a sample of 521 participants in the programme show that the majority of women chose a birth control method that was not permanent, and race did not play a statistically significant role in explaining the birth control choices among the women. Rather, the participant's age and the number of pregnancies she had experienced were more influential. The findings suggest that the prior criticisms of the programme for targeting minority and inherently vulnerable, addicted women for sterilisation are unsupported. Women in this study appeared to follow the larger trends among women of all races and socioeconomic backgrounds in choosing permanent birth control: they were older and had more children. [ABSTRACT FROM AUTHOR]