PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

How does incident solar radiation affect urban canyons?

Prediction of the upward-to-downward reflection ratio of glass bead retro-reflective material applied to the outer walls of buildings

How does incident solar radiation affect urban canyons?
2021-01-26
(Press-News.org) Overview: Jihui Yuan (Assistant Professor, Department of Architecture and Civil Engineering, Toyohashi University of Technology) proposed a numerical bead model to predict the upward-to-downward reflection ratio of glass bead retro-reflective (RR) material purposed for urban heat island (UHI) mitigation and reducing energy consumption. It revealed that the retro-reflectivity of glass bead RR material gradually increases from morning to noon, at which time it begins to gradually decrease. These results will contribute to existing research on the absorption or reflection of solar radiation to improve urban thermal and lighting conditions, and to reduce building energy consumption.

Details: Various measures for UHI mitigation and reduced building energy consumption have been widely implemented. Further, the solar reflectivity of the surrounding pavement and outer wall surfaces of a building are reported to be important factors that affect the air-conditioning load of the building, which is directly related to its energy use. Rooftops covered with diffuse highly reflective (DHR) materials (i.e., highly reflective paints) can reflect solar radiation to the sky if there are no high buildings in the vicinity. However, if there are high buildings nearby, much of the solar radiation will be reflected to neighboring buildings and roads, where it will be absorbed to exacerbate the UHI phenomenon. Thus, although DHR materials are widely applied to building facades, RR materials have been recommended as a replacement to mitigate the UHI phenomenon and reduce building energy consumption.

However, RR materials are still in the research and development phase and have not been used practically. Most research indicates that when the incident angles of sunlight become very large, the RR capacity is critically reduced, and the downward solar reflectivity, such as specular reflectivity, increases. In addition, the downward solar radiation from building facades not only negatively impacts pedestrians, but it also heats the urban environment through the heat absorbed by the ground surface; thus, downward solar radiation is regarded as a major contributor to the UHI phenomenon. Therefore, in consideration of how much a change in incident angle can affect the RR capacity and downward solar reflectivity of RR materials, a comprehensive prediction is needed.

Thus, Assistant Professor Jihui Yuan within the Department of Architecture and Civil Engineering at Toyohashi University of Technology, in collaboration with researchers at Osaka City University, proposed a glass bead numerical model to predict the upward-to-downward reflection ratio of glass bead-type RR materials. The results of this study have been published online in advance in the Elsevier journal Urban Climate in March 2021.

As mentioned previously, to better understand the reflection principle of glass bead-type RR materials, a glass bead numerical model was developed and simulated. The simulation was performed to evaluate glass bead-type RR material sunlight reflection by analyzing the retro-reflectivity and upward-to-downward reflection ratio of glass beads.

Future Outlook: Future work will focus on exploring methods to suppress the downward reflecting light and on attempting to develop the RR materials that can minimize it. Future work will also focus on the development of more accurate models for the evaluation of the RR properties of RR materials, and on performing actual optical measurements of RR materials. If we can predict directional reflection characteristics of RR materials applied to building facades, such as the upward-to-downward reflection ratio, then we would be able to apply these RR materials to the exterior surfaces in different directions to optimize the absorption or reflection of solar radiation; this would ultimately improve urban thermal and lighting conditions, and reducing energy consumption.

INFORMATION:

Funding agency: This work has received financial support from the Japan Science and Technology Agency (Grant number: JPMJTM20EE), and Education and Research Activation Foundation (Youth Studies) of Toyohashi University of Technology in Japan. The authors are grateful for their financial support.

Reference: Jihui Yuan, Kazuo Emura and Craig Farnham (2021). Evaluation of retro-reflective properties and upward to downward reflection ratio of glass bead retro-reflective material using a numerical model. Urban Climate, Vol. 36, March 2021, 100774, DOI: 10.1016/j.uclim.2021.100774.


[Attachments] See images for this press release:
How does incident solar radiation affect urban canyons?

ELSE PRESS RELEASES FROM THIS DATE:

Addressing health disparities in diabetes requires a broader look at systemic racism

2021-01-26
WASHINGTON--Poor social conditions caused by systemic racism contribute to health disparities in people with diabetes, according to a paper published in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism. Minorities are disproportionately affected by diabetes because of poor social conditions that contribute to negative health outcomes such as poverty, unsafe housing, lack of access to healthy food and safe physical activity, and inadequate employment and educational opportunities. These are known as the social determinants of health and are the result of residential ...

90-day vaginal ring shows promise as method for preventing both HIV and pregnancy

2021-01-26
PITTSBURGH, 26 January 2021 - A vaginal ring containing the antiretroviral drug dapivirine and the contraceptive hormone levonorgestrel delivered sustained levels of each drug when used continuously for 90 days - levels likely sufficient to serve its dual purpose for protecting against both HIV and unwanted pregnancy, according to findings of a new study. Results of the Phase I study of the 90-day dual-purpose ring are being presented at the HIV Research for Prevention (HIVR4P) Virtual Conference, or HIVR4P // Virtual, which is taking place over the course of ...

Crunch! Underwater acoustics expose 'shell-crushing' sounds in a large marine predator

2021-01-26
"Shell-crushing" - exactly what it sounds like - is a predatory mode used by numerous marine life from crabs to octopuses to large fishes and mammals when they eat hard-shelled mollusks like clams, oysters and conchs. These predators have to break apart the shell using robust claws or fortified jaws to access the prey's soft tissues. Despite its prevalence in the marine environment, this feeding behavior has remained elusive to study remotely, particularly for larger marine animals that destroy shells almost completely, leaving behind little trace. Moreover, because they are highly mobile, scientists have difficulty in directly observing their foraging habits, which is why the ecology of shell-crushing (durophagy) remains ...

Tungsten-substituted vanadium oxide breathes fresh air into catalyst technology

Tungsten-substituted vanadium oxide breathes fresh air into catalyst technology
2021-01-26
Tokyo, Japan - Researchers from Tokyo Metropolitan University have created a new tungsten-substituted vanadium oxide catalyst for breaking down harmful nitrogen oxides in industrial exhaust. Their new catalyst material works at lower temperatures and does not suffer major drops in performance when processing "wet" exhaust, resolving a major drawback in conventional vanadium oxide catalysts. They found that the unaggregated dispersal of atomic tungsten in the original crystal structure plays a key role in how it functions. Selective catalytic reduction (SCR) is an essential technology for keeping air clean. Industrial exhaust is passed through catalytic units and reacted with ...

Beauty in imperfection: How crystal defects can help convert waste heat into electricity

Beauty in imperfection: How crystal defects can help convert waste heat into electricity
2021-01-26
If we are to prevent the impending environmental crisis, it is imperative that we find efficient and sustainable ways to avoid being wasteful. One area with much room for improvement is the recycling of waste heat from industrial processes and technological devices into electricity. Thermoelectric materials are at the core of research in this field because they allow for clean power generation at little cost. For thermoelectric materials to be used in vastly different fields such as steel works and transportation, they need to be able to operate in both high and low temperature regimes. In this regard, "half-Heusler Ni-based ...

Cannabis use both helps and hurts entrepreneurial creativity

2021-01-26
VANCOUVER, Wash. -When entrepreneurs dream up ideas for new businesses, cannabis use might help, and hinder, their creativity, according to a new study in the Journal of Business Venturing by Washington State University researchers. The study found that cannabis-using entrepreneurs generated new business ideas such as a weightless, gravity-free virtual reality workout, that were more original, but less feasible, compared to those who do not use cannabis. "Originality and feasibility are both crucial in entrepreneurship--one without the other limits potential value creation," said Benjamin Warnick, lead author of the study and assistant professor in the ...

'Brain training' may be an effective treatment for post-traumatic stress disorder

2021-01-26
LONDON, ON - Neurofeedback, also called 'brain training,' consists of exercises where individuals regulate their own brain activity. In a new study from Lawson Health Research Institute and Western University, researchers have found that neurofeedback may be an effective treatment for individuals with post-traumatic stress disorder (PTSD). Published in END ...

Can dogs rapidly learn words?

Can dogs rapidly learn words?
2021-01-26
A new study found that talented dogs can learn new words after hearing them only four times. While preliminary evidence seems to show that most dogs do not learn words (i.e. names of objects), unless eventually very extensively trained, a few individuals have shown some exceptional abilities. The Family Dog Project research team at the Department of Ethology, Eötvös Loránd University, Budapest is investigating on these exceptionally talented dogs who seem to learn words in the absence of any formal training, but simply by being exposed to playing with their owners in the typical way ...

Toddlers who use touchscreens may be more distractible

2021-01-26
Toddlers with high daily touchscreen use are quicker to look at objects when they appear and are less able to resist distraction compared to toddlers with no or low touchscreen use - according to new research from Birkbeck, University of London, King's College London and University of Bath. The research team say the findings are important for the growing debate around the role of screen time on toddlers' development especially given the increased levels of screen time seen during the COVID-19 pandemic. Lead researcher Professor Tim Smith, from Birkbeck's ...

Study sheds new light on the behaviour of the giant carnivorous dinosaur Spinosaurus

2021-01-26
New research from Queen Mary University of London and the University of Maryland, has reignited the debate around the behaviour of the giant dinosaur Spinosaurus. Since its discovery in 1915, the biology and behaviour of the enormous Spinosaurus has puzzled palaeontologists worldwide. It was recently argued that the dinosaur was largely an aquatic predator, using its large tail to swim and actively pursue fish in the water. The new study, published today in Palaeontologia Electronica, challenges this recent view of Spinosaurus suggesting that whilst it likely fed ...

LAST 30 PRESS RELEASES:

Call for papers: 14th Asia-Pacific Conference on Transportation and the Environment (APTE 2025)

A novel disturbance rejection optimal guidance method for enhancing precision landing performance of reusable rockets

New scan method unveils lung function secrets

Searching for hidden medieval stories from the island of the Sagas

Breakthrough study reveals bumetanide treatment restores early social communication in fragile X syndrome mouse model

Neuroscience leader reveals oxytocin's crucial role beyond the 'love hormone' label

Twelve questions to ask your doctor for better brain health in the new year

Microelectronics Science Research Centers to lead charge on next-generation designs and prototypes

Study identifies genetic cause for yellow nail syndrome

New drug to prevent migraine may start working right away

Good news for people with MS: COVID-19 infection not tied to worsening symptoms

Department of Energy announces $179 million for Microelectronics Science Research Centers

Human-related activities continue to threaten global climate and productivity

Public shows greater acceptance of RSV vaccine as vaccine hesitancy appears to have plateaued

Unraveling the power and influence of language

Gene editing tool reduces Alzheimer’s plaque precursor in mice

TNF inhibitors prevent complications in kids with Crohn's disease, recommended as first-line therapies

Twisted Edison: Bright, elliptically polarized incandescent light

Structural cell protein also directly regulates gene transcription

Breaking boundaries: Researchers isolate quantum coherence in classical light systems

Brain map clarifies neuronal connectivity behind motor function

Researchers find compromised indoor air in homes following Marshall Fire

Months after Colorado's Marshall Fire, residents of surviving homes reported health symptoms, poor air quality

Identification of chemical constituents and blood-absorbed components of Shenqi Fuzheng extract based on UPLC-triple-TOF/MS technology

'Glass fences' hinder Japanese female faculty in international research, study finds

Vector winds forecast by numerical weather prediction models still in need of optimization

New research identifies key cellular mechanism driving Alzheimer’s disease

Trends in buprenorphine dispensing among adolescents and young adults in the US

Emergency department physicians vary widely in their likelihood of hospitalizing a patient, even within the same facility

Firearm and motor vehicle pediatric deaths— intersections of age, sex, race, and ethnicity

[Press-News.org] How does incident solar radiation affect urban canyons?
Prediction of the upward-to-downward reflection ratio of glass bead retro-reflective material applied to the outer walls of buildings