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Human subject experiments were conducted to investigate the influences of thermal load and thermal sensation under various outdoor radiation environments. The experiments were conducted at locations simulating the application of ground surface materials with different solar reflectance, tall trees, green walls, hedges, and retro-reflective materials. The results revealed that a quantitative evaluation of the heat transfer between the human body and the surrounding environment using the human thermal load may be connected to the thermal sensation felt under various radiation environments. The improved effects of the thermal sensation by the decrease in reflected solar radiation from the ground, the decrease in transmitted solar radiation from the sky, the decrease in infrared radiation from the wall surface, the decrease in reflected solar radiation toward the human body from a window surface, and the shielding of infrared radiation from the ground surface were quantitatively evaluated based on the human thermal load. [ABSTRACT FROM AUTHOR]

The air temperatures are generally found to be higher in the urban areas in comparison with the suburban or rural areas. One of the countermeasures to mitigate this urban heat island is to coat the surfaces of buildings with paint that has higher solar reflectance; the method is commonly referred to as “cool painting”. It is important to evaluate the solar reflectance of the paints used for such paintings. Though solar reflectance can be measured by a spectrophotometer with an integrating sphere, accurate numerical prediction of reflective properties of the painted layer including arbitrary pigments can contribute to further development of the cool paint material. The effect of diffuse reflection in the painted layer is more significant than that of specular reflection on the painted surface. It is also important to evaluate the scattering properties of pigments, which are related to the reflection performance. For evaluating the scattering properties of a pigment in a medium, anisotropic scattering should be considered. In this study, we applied the radiation element method for predicting the solar reflectance of a painted layer. The hemispherical spectral reflectance of a painted layer, including TiO 2 , ZnO or Al 2 O 3 , was evaluated. Our results showed that spectral reflectance of a painted layer with arbitrary values of particle sizes, volume fraction of pigment, and coating thickness can be calculated by this method. Further, the validity of this numerical method was evaluated by comparison with the reflective property of the actual painted layer by means of spectrophotometry. [ABSTRACT FROM AUTHOR]

The difference of photon arrival time, which is known as spectral lag, is well known characteristics of gamma-ray bursts (GRBs). In particular, long duration GRBs show a soft lag which means that high energy photons arrive earlier than soft photons. The lag-luminosity relation is the empirical relationship between the isotropic peak luminosity and the spectral lag. We calculated the spectral lags for 40 known redshift GRBs observed by Swift addition to the previous 31 GRB samples. We confirmed that most of our samples follow the lag-luminosity relation. However, we noticed that there are some GRBs which show a significant scatter from the relation. We also confirm that the relationship between the break time and the luminosity of the X-ray afterglow (so-called Dainotti relation) extends up to the lag-luminosity relation. [ABSTRACT FROM AUTHOR]

Abstract: Human thermal comfort is studied as a countermeasure to the thermal stress in outdoor urban space. Outdoors, people experience the strong impact of solar radiation in states that are unsteady and non-uniform. The feeling of comfort is a mixed sensation that can be easier to improve overall, as compared with a global large-scale effort, and can lead to improved ways of saving energy and reducing costs. Moreover, this can be directly beneficial to human experience and fulfill natural human desires. Since a thermal comfort index is a useful tool for understanding the present state and evaluating the impact of countermeasures, we examine the effects of the human thermal load, which is a thermal comfort index based on the energy balance of the human body. In a steady state, and even in an unsteady state with its variations in weather and human factors, thermal comfort values can generally be obtained by using the overall human thermal load. The reason for this is that the human thermal load takes physiological factors in account as well as weather parameters. This leads to the idea that thermal sensations follow from the human thermal load, which can then well describe a given human environment. As a result, human sensations as expressed by the human thermal load pave the way to the creation of comfortable urban spaces that require minimum expense and energy as an example of simple heat transport model focusing on urban outer structure. [Copyright &y& Elsevier]

A Large Eddy Simulation (LES) model was developed to investigate vehicle-induced turbulence and its effect on turbulent dispersion. The instantaneous behaviour of vehicle exhausts and the time-space averaged distributions of flow and concentration statistics on the roadway were estimated. The patterns of mean flow are significantly different between the one-way and the two-way traffic cases. In the vehicle passing area, the standard deviations of the spanwise and the vertical fluctuation velocities are two times larger than the maximum of the mean velocity. The relationship between the growth rate of vertical plume width and the background cross flow was also investigated. [ABSTRACT FROM AUTHOR]

We are developing and operating the automatic telescope Aoyama Gakuin University Robotic Optical Monitor for Astrophysical objects (AROMA) in the Sagamihara Campus of Aoyama Gakuin University. AROMA is composed of two observational equipments, AROMA-N and AROMA-W. AROMA-N is a 30-cm aperture telescope system for rapid follow-up observations of the optical afterglow of gamma-ray bursts. Automatic analysis pipeline for AROMA-N has been developed and is working. The other observational equipment AROMA-W is a wide-field observation system using multiple digital single-lens reflex cameras. It covers a large FOV of about 35° × 25°. AROMA-W provides photometric data in four bands with a limiting V magnitude of about 12-13 mag. Software to analyze massive image data automatically is being developed. We plan to monitor the luminosities of all the stars in the FOV of AROMA-W, detect optical transients, and trigger a follow-up observation with AROMA-N. We report on the development status and observational results of AROMA. [ABSTRACT FROM AUTHOR]

The role of urban surfaces in climate is recognized worldwide. Cool pavements such as reflective and water-retaining pavements contribute to the mitigation of urban heat. To optimize the cooling performance of a combination of reflective and evaporative characteristics, water-retaining (WR) pavements, with reflectance values of 13% (WR13) and 25% (WR25), were used and compared to a conventional asphalt pavement (AS). In addition to measuring surface and atmospheric temperatures, human-energy balance known as "human-thermal load" was assessed using perceptive responses obtained from participants (n = 78). Experimental insolation conditions were classified as low-, medium-, and high-based on radiation effects. Water-retaining pavements demonstrated significant surface temperature reductions compared to the overall AS; however, air temperature and humidity above the pavement were less sensitive, and they were not significantly different between the two distinct pavements. Under high insolation, local thermal comfort improved and skin temperatures of the lower body reduced. These consequently reduced the temperature perceived in the whole-body and improved the thermal environment on the surface of WR13. These results can be reasonably explained using the human-thermal load. The increase in thermal load from reflected solar radiation is limited below a certain level of insolation. The overall radiation received by WR13 was moderate from both ground-reflected and -sourced infrared radiation sources. The human-thermal load of WR13 was significantly different from that of AS under high insolation. A modest reflective pavement, such as WR13, is anticipated to improve human thermal comfort. • Water-retaining and asphalt pavements are evaluated for human-thermal environments. • Methodology for the evaluation of human-thermal comfort on pavements is proposed. • Human comfort on pavements is determined by the extents of radiation components. • Water-retaining pavement with a lower reflectance is beneficial for heat mitigation. [ABSTRACT FROM AUTHOR]

Artificial impervious surfaces are one of the most significant factors contributing to urban heat islands (UHIs). Adapting to UHIs is a challenge in achieving thermal comfort. We conducted a quantitative and subjective evaluation of a closely paved novel water-retaining pavement (WR) and a conventional dense-asphalt pavement (AS). We investigated the thermal states of humans based on the human energy balance known as "human thermal load" as an indicator for the assessment, and the original human thermal load method was improved for assessing nonuniform environments such as pavements. We looked for individual thermal perceptions simultaneously. The experiment was conducted in typical summer weather. The surface temperature of the WR was found to be significantly lower, by 9.5 °C, while the air temperature and humidity above both pavements were not significantly different. Thus, air conditions did not directly affect the sensible and latent heat loss. The reflected solar radiation was significantly larger, and the infrared radiation was significantly smaller on the WR than on the AS due to the lower surface temperature from the water evaporation and higher reflectance. Further, the human thermal load at a pedestrian level of 1.5 m was found to be significantly different: 237 W/m2 for AS and 215 W/m2 for WR. In a subjective evaluation, the perceptions of WR tend to be distributed in smaller human thermal load, thereby resulting in a cooler and comfortable sensation. Therefore, we demonstrated that when compared to AS, WR significantly improves thermal comfort. [ABSTRACT FROM AUTHOR]

Thermal environment of urban areas in the summertime has become harmful to human health due to global warming and the urban heat island (UHI) effect. Mobile observations enable us to obtain the distribution of air temperature at microscale, such as urban blocks, which cannot be captured by the coarse network of meteorological sites. A series of mobile measurements was executed in the central area of Osaka City in Japan, around the Nakanoshima district which lies between two rivers, to investigate the air temperature and humidity distributions in a built-up area under sea breeze conditions. Upper wind and surface temperature of the rivers were also observed using pilot balloons and infrared thermography camera, respectively. The mean air temperature in Nakanoshima was generally lower than that of the surrounding area. Urban geometries such as building density and building height seem to affect the mean air temperature by changing the ventilation efficiency. Humidity was inversely correlated with air temperature distribution but was higher at the confluence of rivers and green parks. The depth of the sea breeze layer was found to be about 1 km. Sea breezes close to the ground surface penetrated the city along the rivers, sandwiching the Nakanoshima district. During the daytime, the surface temperatures of the rivers were lower than the air temperature observed at the nearest stationary observation point, and the difference reached approximately 2 °C. [ABSTRACT FROM AUTHOR]

• Bubble point pressures measured for ethanol-propene, DME, R1234ze(E) binary mixtures. • PR equation with WSmodel reliably correlated data without false azeotropy or LLE. • Bubble point pressures of R1234ze(E)-ethanol similar to those of propane -ethanol. For the design of spray propellants, bubble point pressures were measured for binary mixtures of ethanol with propane, dimethyl ether (DME) or trans -1,3,3,3-tetrafluoropropene (R1234ze(E)), with a static type apparatus at (293.15–313.15) K. Experimental data were correlated with the Peng-Robinson (PR) and Stryjek-Vera (PRSV) equations of state using the Wong-Sandler (WS) mixing rules. The NRTL activity coefficient model in the WS mixing rules was effective for correlation of systems that exhibited large non-idealities (ethanol - propane, ethanol - R1234ze(E)). Correlation of the bubble point pressures with the PRSV equation of state and WS mixing rules was to within an average of 2.391% absolute deviation in pressure for all systems, which is considered to be sufficient for design of spray devices with propellants that have low global warming potential. Image, graphical abstract [ABSTRACT FROM AUTHOR]

For design of spray paint using dimethyl ether (DME) as a propellant, bubble point pressures were measured for two binaries, DME + acetone, and DME + 1-hexanol, and a ternary, DME + acetone + 1-hexanol, with a static type apparatus at temperatures of (293.15–313.15) K. The experimental data were correlated with the Peng-Robinson-Stryjek-Vera (PRSV) equation of state using conventional mixing rules. Binary interaction parameters, for DME + acetone, and DME + 1-hexanol, were determined from the experimental data and those for acetone + 1-hexanol were determined from literature isobaric data. Vapor-liquid equilibrium (VLE) were also estimated for the ternary. The mole ratio of propellant, DME, was to evaluate the thickener performance of 1-hexanol as a spray paint additive. Image 1 • Bubble point pressure was measured for dimethyl ether (DME) + acetone, DME + 1-hexanol, and DME + acetone + 1-hexanol. • Peng-Robinson-Stryjek-Vera equation of state was able to sufficiently correlate the bubble point pressures. • Performance of 1-hexaxe as a thickener for color spray was investigated from phase diagram of DME + acetone + 1-hexanol. [ABSTRACT FROM AUTHOR]