Solar flares typically have an impulsive phase that is followed by a gradual phase as best seen in soft X-ray emissions. A recent discovery based on the EUV Variability Experiment observations on board the Solar Dynamics Observatory (SDO) reveals that some flares exhibit a second large peak separated from the first main phase peak by tens of minutes to hours, which is coined as the flare's EUV late phase. In this paper, we address the origin of the EUV late phase by analyzing in detail two late phase flares, an M2.9 flare on 2010 October 16 and an M1.4 flare on 2011 February 18, using multi-passband imaging observations from the Atmospheric Imaging Assembly on board SDO. We find that (1) the late phase emission originates from a different magnetic loop system, which is much larger and higher than the main phase loop system. (2) The two loop systems have different thermal evolution. While the late phase loop arcade reaches its peak brightness progressively at a later time spanning for more than one hour from high to low temperatures, the main phase loop arcade reaches its peak brightness at almost the same time (within several minutes) in all temperatures. (3) Nevertheless, the two loop systems seem to be connected magnetically, forming an asymmetric magnetic quadruple configuration. (4) Further, the footpoint brightenings in UV wavelengths show a systematic delay of about one minute from the main flare region to the remote footpoint of the late phase arcade system. We argue that the EUV late phase is the result of a long-lasting cooling process in the larger magnetic arcade system.

It is recently noted that solar eruptions can be associated with the contraction of coronal loops that are not involved in magnetic reconnection processes. In this paper, we investigate five coronal eruptions originating from four sigmoidal active regions, using high-cadence, high-resolution narrowband EUV images obtained by the Solar Dynamic Observatory (SDO). The magnitudes of the flares associated with the eruptions range from the GOES-class B to X. Owing to the high-sensitivity and broad temperature coverage of the Atmospheric Imaging Assembly (AIA) onboard SDO, we are able to identify both the contracting and erupting components of the eruptions: the former is observed in cold AIA channels as the contracting coronal loops overlying the elbows of the sigmoid, and This is also implied by the relationship between contraction and expansion, i.e., their timing and speed.

In this section, we comprehensively recap the method used 1 . Neural networks, especially convolutional neural networks (CNNs), have proved their high potential in computer vision in various fields such as autonomous vehicles, medical imaging and remote sensing. Goodfellow et al. 2014

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With the quickening of environmental pollution control in China, the concrete measures of “plastic limit” and “plastic ban” were put forward one after another. At the same time, the Law of the People’s Republic of China on the Prevention and Control of Environmental Pollution by Solid Waste will be formally revised and implemented in September 2020. This fully demonstrates the importance we attach to ecological protection and sustainable development of the environment and our determination to control environmental pollution. At present, with the popularization of e-commerce, the fragmentation of consumption, the penetration of online shopping in rural areas is getting bigger and bigger, and the express delivery industry is showing explosive growth. Especially under the epidemic, consumers’ consumption behaviors and consumption patterns have changed greatly. Network consumption behavior increased significantly, carton, plastic bags and other packaging products demand increased significantly. It consumes a lot of resources, such as paper and plastic products, and also produces a lot of packaging waste. Through the analysis and comparison of several disposable plastic packaging materials in green logistics, the importance of green packaging in green logistics is discussed, which has a strong inspiration for environmental protection and the development of green logistics.