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The advanced travel information system is a prominent intelligent transportation system for which variable message signs (VMSs) are the major components. In Iran, more attention has been paid to sign placement than to other components which are complementary to placement and combine to create relevant and effective messages for the driver. The current study used a stated preference survey to investigate the attitudes and reactions of drivers to VMS information that then were used to build models to reveal the reasons behind driver reactions to a VMS request to change route. The survey included variables affecting driver decisions, such as driver characteristics, attitude and perceptions of current VMS information and traffic in general. The influence of personality traits as subjective factors for driver behavior regarding route choice also was investigated. The results of the estimation of sequential hybrid binary logistic regression model showed that visual health had a significant positive effect on the driver decisions to divert to an alternate route when the VMS messages related to an accident or traffic congestion. Provision of expected delay information about the current route was found to be the most significant factor causing drivers to change route when a VMS indicated traffic congestion ahead. Personality traits such as Agreeableness, neuroticism, extraversion and openness significantly affected driver decisions about changing route when the VMS indicated traffic congestion or adverse weather conditions. [ABSTRACT FROM AUTHOR]

This paper presents the modeling and simulation of an industrial-scale chemical looping combustion (CLC) power plant, including all process units (reactors, flue gas treatment units, heat integration, steam cycle, and CO2 compression train). A model of a 525 MWth CLC power plant was built using a rigorous representation of the solid fuel and oxygen carrier. Petcoke was considered the main fuel of interest in this study, and it is compared with other solid fuels. The flue gas compositions obtained with the model show that cleanup units are mandatory to comply with CO2 quality requirements. High levels of flue gas treatment, including 97.1% deNOx and 99.4% deSOx, are needed to achieve typical specifications for captured CO2. This is mainly due to the high level of contaminants in the fuel, but also to the absence of nitrogen in the CLC flue gas, thus resulting in higher concentrations for all substances. The high level of flue gas treatment is thus one of the important challenges for solid fuel combustion in CLC. The overall CO2 capture efficiency of the plant is estimated to be as high as 94%. Regarding the energy balance, a process net efficiency of 38% is obtained. Comparing the results with other available technologies shows that CLC exhibits one of the highest net plant efficiencies and carbon capture rates. CLC is thus a promising technology to produce clean energy from solid fuels. Finally, based on a sensitivity analysis, it is shown that process efficiency is mainly affected by the design and performance of the CLC furnace, the steam injection rate in the fuel reactor, the char separation efficiency, and the excess oxygen in the air reactor. [ABSTRACT FROM AUTHOR]

A complex set of factors may affect transportation mode choice. While earlier studies have often considered objective factors in determining preferences of public transport use as a sustainable transportation, subjective factors such as personality traits are underexplored. Therefore, this study aimed to investigate the influence of personality traits on the number of future public transport use. Additionally, "car habit" and "intention toward using public modes" were considered to be important. For this purpose, a case study from departure passengers at Imam Khomeini International Airport (IKIA, Tehran, Iran) was conducted between January and February 2015 at IKIA. Results of structural equation modeling (SEM) shows that only neuroticism and extraversion personality traits were significant in determining future public transportation mode choice. However, the model indicates that these traits indirectly influence intention and car habit. Neuroticism was found to have a total effect of 0.022 on future public transport use, which represents a negative association with public transport use, while extraversion positively influenced future public transport use with a total effect of 0.031. Moreover, the results found interestingly that car access had a better fit to the data than the number of cars in household (NCH); both had significant positive effect on car habit, but only car access had a significant influence on intention. Furthermore, the effect of socio-demographic variables such as age, gender, educational level, income level, and body mass index (BMI) were determined to be significant in identifying choice of future transport mode to airports, which is explained in the discussion section of this paper. [ABSTRACT FROM AUTHOR]

Built environment (BE), as an objective variable, plays a substantial role in urban residents' behavior. However, the perception toward a BE, as a subjective variable, varies among people. To identify the role of perception toward BE, we used a stated preference (SP) survey conducted in January--February 2015 at the Imam Khomeini International Airport (IKIA), Tehran, Iran. The data was drawn from 641 individuals; 359 of them were residents of Tehran. For the estimation of the model, a hybrid discrete choice model was used to capture the latent variable, in addition to mode attributes and trip conditions, with 1795 SP observations. Psychometric questions concerned the perception of ease in access to main streets or highways and good traffic conditions within their residential areas. The results showed that the latent variable (positive perception toward built environment or PBE) had a significant positive effect on people's willingness to park at the airport. Moreover, the gender, age, marital status, level of education, experience living in a foreign country, and income level also influenced the formation of perception toward the BE and airport transportation mode choice. [ABSTRACT FROM AUTHOR]

Predicting bubble properties in fluidized beds is of high interest for reactor design and modeling. While bubble sizes and velocities for low velocity bubbling fluidized beds have been examined in several studies, there have been only few studies about bubble behavior at superficial gas velocities up into the turbulent regime. For this reason, we performed a thorough investigation of the size, shape and velocity of bubbles at superficial gas velocities ranging from 0.18 m/s up to 1.6 m/s. Capacitance probes were used for the determination of the bubble properties in three different fluidized bed facilities sized of 0.1 m, 0.4 m and 1 m in diameter. Particles belonging to Geldart's group B (Sauter mean diameter: 188 µm, solid density: ρs = 2600 kg/m3) were used. Correlations for the determination of bubble phase holdup, vertical bubble length and bubble velocity are introduced in this work. The shape of bubbles was found to depend on superficial gas velocity. This implies that at large superficial gas velocities the horizontal size of a bubble must be much smaller in comparison to its vertical size. This leads to a decrease of pressure fluctuations, which is observed in the literature as a characteristic of transitioning into a turbulent regime. [ABSTRACT FROM AUTHOR]