Computer Sciences

Creating 3-D maps of complex buildings for disaster management

In case of an emergency, first responders like the fire brigade need up-to-date information. Two-dimensional maps are a common source of information, but they can be difficult to read in an emergency situation. UT Ph.D. student ...

Machine learning & AI

Software spots and fixes hang bugs in seconds, rather than weeks

Hang bugs—when software gets stuck, but doesn't crash—can frustrate both users and programmers, taking weeks for companies to identify and fix. Now researchers from North Carolina State University have developed software ...

Electronics & Semiconductors

Arm: semiconductor giant powering world's smartphones

Arm, the British semiconductor designer being sold by Japanese group Softbank to US chip company NVIDIA for up to $40 billion, is a technological power in smart phones worldwide.

Electronics & Semiconductors

A new approach to database management in solid-state drives

The ever-increasing workload of data centers calls for new ways to store and access data. Researchers from the Daegu Gyeongbuk Institute of Science and Technology, Korea, have developed a new approach to manage databases ...

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Cloud

A cloud is a visible mass of droplets or frozen crystals suspended in the atmosphere above the surface of the Earth or another planetary body. A cloud is also a visible mass attracted by gravity, such as masses of material in space called interstellar clouds and nebulae. Clouds are studied in the nephology or cloud physics branch of meteorology.

On Earth the condensing substance is typically water vapor, which forms small droplets or ice crystals, typically 0.01 mm in diameter. When surrounded by billions of other droplets or crystals they become visible as clouds. Dense deep clouds exhibit a high reflectance (70% to 95%) throughout the visible range of wavelengths. They thus appear white, at least from the top. Cloud droplets tend to scatter light efficiently, so that the intensity of the solar radiation decreases with depth into the gases, hence the gray or even sometimes dark appearance at the base. Thin clouds may appear to have acquired the color of their environment or background and clouds illuminated by non-white light, such as during sunrise or sunset, may appear colored accordingly. In the near-infrared range, clouds look darker because the water that constitutes the cloud droplets strongly absorbs solar radiation at those wavelengths.

This text uses material from Wikipedia, licensed under CC BY-SA