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Topic Review
Urban Transportation Meteorological Observation
With the advantages of various advanced technologies from multiple aspects, researchers could further expand explorations on urban transportation meteorological observations. Associated theoretical studies and practical investigations are also to be carried out to provide solid scientific foundations for urban transportation disaster prevention and mitigation, for implementing the action of meteorological guarantees, and for the construction of a high-quality smart society.
  • 424
  • 25 Nov 2022
Topic Review
Weakly Supervised Object Detection for Remote Sensing Images
To account for the lack of fine-grained annotations, such as object bounding boxes, several object detection methods have been developed that leverage only coarse-grain annotations (especially image-level labels indicating only the presence or absence of an object). This approach is called inexact Weak Supervision and introduces a new branch of Object Detection called Weakly Supervised Object Detection. Given an image, Remote Sensing Fully Supervised Object Detection (RSFSOD) aims to locate and classify objects based on Bounding Boxes annotations. Differently from RSFSOD, Remote Sensing Weakly Supervised Object Detection aims to precisely locate and classify object instances in Remote Sensing Images using only image-level labels or other types of coarse-grained labels (e.g., points or scribbles) as ground truth. 
  • 393
  • 24 Nov 2022
Topic Review
Spinophorosaurus
Spinophorosaurus is a genus of sauropod dinosaur that lived in what is now Niger during the Middle Jurassic period. The first two specimens were excavated in the 2000s by German and Spanish teams under difficult conditions. The skeletons were brought to Europe and digitally replicated, making Spinophorosaurus the first sauropod to have its skeleton 3D printed, and were to be returned to Niger in the future. Together, the two specimens represented most of the skeleton of the genus, and one of the most completely known basal sauropods of its time and place. The first skeleton was made the holotype specimen of the new genus and species Spinophorosaurus nigerensis in 2009; the generic name ("spine-bearing lizard") refers to what was initially thought to be spiked osteoderms, and the specific name (Niger and -ensis) refers to where it was found. A juvenile sauropod from the same area was later assigned to the genus. The subadult holotype specimen is estimated to have been around 13 m (43 ft) in length, whereas the paratype was about 14 m (46 ft) long. The shoulder height reached by these individuals was estimated at around 4 m (13 ft), and the weight at about 7 metric tons (7.7 short tons). The braincase was short, deep, and broad, and the neuroanatomy was in some ways intermediate between that of basal sauropodomorphs and the more derived neosauropods. The teeth were spatulate (spoon shaped) and had large spaced denticles at the top of the crown, an ancestral feature in sauropods. The neck of Spinophorosaurus is one of the most completely known among sauropods, containing 13 vertebrae. The dorsal vertebrae had multiple small air-filled internal chambers, a feature typical of later more-derived sauropods. The tail was powered by strong musculature and had a rear section that was rather rigid due to long and overlapping chevron bones. Bones originally thought to be osteoderms bearing spikes placed on the tail tip were later suggested to be clavicles. Spinophorosaurus has been classified as either a very basal sauropod, or inside Eusauropoda, a more derived group. The anatomy, age, and location of specimens indicate that important developments in sauropod evolution may have occurred in North Africa, possibly controlled by climatic zones and plant biogeography. Features of the vestibular apparatus suggest that vision and coordinated eye, head, and neck movements were important in Spinophorosaurus. 3D models of the skeleton have been used to test its range of motion. One study suggests it may have been a high browser, and another examined possible mating postures. Sutures between the neural arches with the centra of the vertebrae were more complex in the front part of the trunk of Spinophorosaurus, since stresses were probably greatest in that region. Spinophorosaurus is known from the Irhazer Shale, a geological formation thought to be Middle Jurassic in age. It was formed by deposits from rivers and lakes in a great river-valley system.
  • 673
  • 24 Nov 2022
Topic Review
National Association of Manufacturers
The National Association of Manufacturers (NAM) is an advocacy group headquartered in Washington, D.C., United States, with additional offices across the country. It is the nation's largest manufacturing industrial trade association, representing 14,000 small and large manufacturing companies in every industrial sector and in all 50 states. Jay Timmons has led the organization as President and CEO since 2011. A 2018 article by Business Insider described the NAM as "a behemoth in the US capital, receiving unfettered access to the White House and top lawmakers on Capitol Hill." In 2018, House Ways and Means Chairman Kevin Brady commented that passage of the Tax Cuts and Jobs Act would not have happened without leadership from the National Association of Manufacturers. President Donald Trump addressed the NAM board in 2017.
  • 335
  • 24 Nov 2022
Topic Review
Orbital Effects on Climate
There are various solar/celestial effects that exist which have an effect on Earth's climate. These effects usually occur in cycles, and primarily include how Earth's obliquity, the eccentricity of Earth's orbit, and the precession of the equinoxes and solstices affect Earth's climate. In addition to these effects, there are also other factors that have an effect on Earth's climate. These other factors include how sun activity affects climate and how celestial phenomena, such as meteors, affect Earth's climate. Some of these factors aren't yet well understood, for instance the ice ages occur on 100,000 year cycles, and it's not completely understood why the various effects with this periodicity have such a strong effect on glaciation (see the 100,000-year problem).
  • 788
  • 24 Nov 2022
Topic Review
Halemaʻumaʻu Crater
Halemaʻumaʻu Crater (six syllables: HAH-lay-MAH-oo-MAH-oo) is a pit crater located within the much larger summit caldera of Kīlauea in Hawaii Volcanoes National Park. The roughly circular crater was 770 meters (2,530 ft) x 900 m (2,950 ft) prior to collapses that roughly doubled the size of the crater after May 3, 2018. Halemaʻumaʻu is home to Pele, goddess of fire and volcanoes, according to the traditions of Hawaiian religion. Halemaʻumaʻu means "house of the ʻāmaʻu fern". The crater until recently contained an active lava lake. From 2008, when the current vent inside Halemaʻumaʻu crater first erupted, to April 2015, lava was present inside the vent, fluctuating from 20 to 150 meters below the crater rim. On April 24, 2015 molten lava in the vent, known as the Overlook Crater, became directly visible for the first time from the Jaggar Museum overlook at the Hawaiian Volcano Observatory, when the lava rose to an all-time high level since the Overlook Crater first opened. A few days later, on April 29, the lava started spilling over the rim of the Overlook Crater and onto the floor of Halemaʻumaʻu Crater, ultimately adding a layer of lava approximately 30 feet (9 m) thick to the crater floor. For three years from 2015 to 2018 the lava lake level remained close to the rim, with a further minor overflow event in October 2016 and a significant one in April 2018 that covered a majority of the crater floor in new lava. In early May 2018 the lava level in the Overlook Crater dropped over 700 feet and out of sight, resulting in explosions, earthquakes and large clouds of ash and toxic gas, causing closure of the Kīlauea summit area of the national park from May 10 to September 22. While the park visitor center and headquarters have reopened to the public, the crater is currently in a state of collapse that includes substantial portions of Kīlauea Caldera. The Jaggar Museum overlooking the crater remains closed.
  • 877
  • 24 Nov 2022
Topic Review
Evolutionary History of Life
The evolutionary history of life on Earth traces the processes by which living and fossil organisms evolved, from the earliest emergence of life to the present. Earth formed about 4.5 billion years (Ga) ago and evidence suggests life emerged prior to 3.7 Ga. (Although there is some evidence of life as early as 4.1 to 4.28 Ga, it remains controversial due to the possible non-biological formation of the purported fossils.) The similarities among all known present-day species indicate that they have diverged through the process of evolution from a common ancestor. Approximately 1 trillion species currently live on Earth of which only 1.75–1.8 million have been named and 1.6 million documented in a central database. These currently living species represent less than one percent of all species that have ever lived on earth. The earliest evidence of life comes from biogenic carbon signatures and stromatolite fossils discovered in 3.7 billion-year-old metasedimentary rocks from western Greenland. In 2015, possible "remains of biotic life" were found in 4.1 billion-year-old rocks in Western Australia. In March 2017, putative evidence of possibly the oldest forms of life on Earth was reported in the form of fossilized microorganisms discovered in hydrothermal vent precipitates in the Nuvvuagittuq Belt of Quebec, Canada, that may have lived as early as 4.28 billion years ago, not long after the oceans formed 4.4 billion years ago, and not long after the formation of the Earth 4.54 billion years ago. Microbial mats of coexisting bacteria and archaea were the dominant form of life in the early Archean Epoch and many of the major steps in early evolution are thought to have taken place in this environment. The evolution of photosynthesis, around 3.5 Ga, eventually led to a buildup of its waste product, oxygen, in the atmosphere, leading to the great oxygenation event, beginning around 2.4 Ga. The earliest evidence of eukaryotes (complex cells with organelles) dates from 1.85 Ga, and while they may have been present earlier, their diversification accelerated when they started using oxygen in their metabolism. Later, around 1.7 Ga, multicellular organisms began to appear, with differentiated cells performing specialised functions. Sexual reproduction, which involves the fusion of male and female reproductive cells (gametes) to create a zygote in a process called fertilization is, in contrast to asexual reproduction, the primary method of reproduction for the vast majority of macroscopic organisms, including almost all eukaryotes (which includes animals and plants). However the origin and evolution of sexual reproduction remain a puzzle for biologists though it did evolve from a common ancestor that was a single celled eukaryotic species. Bilateria, animals having a left and a right side that are mirror images of each other, appeared by 555 Ma (million years ago). The earliest complex land plants date back to around 850 Ma, from carbon isotopes in Precambrian rocks, while algae-like multicellular land plants are dated back even to about 1 billion years ago, although evidence suggests that microorganisms formed the earliest terrestrial ecosystems, at least 2.7 Ga. Microorganisms are thought to have paved the way for the inception of land plants in the Ordovician. Land plants were so successful that they are thought to have contributed to the Late Devonian extinction event. (The long causal chain implied seems to involve the success of early tree archaeopteris (1) drew down CO2 levels, leading to global cooling and lowered sea levels, (2) roots of archeopteris fostered soil development which increased rock weathering, and the subsequent nutrient run-off may have triggered algal blooms resulting in anoxic events which caused marine-life die-offs. Marine species were the primary victims of the Late Devonian extinction.) Ediacara biota appear during the Ediacaran period, while vertebrates, along with most other modern phyla originated about 525 Ma during the Cambrian explosion. During the Permian period, synapsids, including the ancestors of mammals, dominated the land, but most of this group became extinct in the Permian–Triassic extinction event 252 Ma. During the recovery from this catastrophe, archosaurs became the most abundant land vertebrates; one archosaur group, the dinosaurs, dominated the Jurassic and Cretaceous periods. After the Cretaceous–Paleogene extinction event 66 Ma killed off the non-avian dinosaurs, mammals increased rapidly in size and diversity. Such mass extinctions may have accelerated evolution by providing opportunities for new groups of organisms to diversify.
  • 1.6K
  • 24 Nov 2022
Topic Review
Archaeogaming
Archaeogaming is an archaeological framework which, broadly speaking, includes the study of archaeology in and of video games as well as the use of video-games for archaeological purposes. To this end, the study can include, but is in no means limited to: the physical excavation of video-game hardware, the use of archaeological methods within game worlds, the creation of video-games for or about archaeological practices and outcomes or the critical study of how archaeology is represented in video-games. Virtual and augmented reality applications in archaeology might also be subsumed within its rubric. M. Dennis states that archaeogaming is “the utilization and treatment of immaterial space to study created culture, specifically through videogames” which “requires treating a game world, a world bounded and defined by the limitations of its hardware, software and coding choices, as both a closed universe and as an extension of the external culture that created it. Everything that goes into the immaterial space comes from its external cultural source, in one way or another.” Taking this into consideration the archaeogaming framework indicates that there is no functional difference between studying archaeology in the physical, material world, and implementing it with regards to the study, critique and creation of video-games for and about archaeology. As such it is said that archaeogaming “requires the same standards of practice as the physical collection of excavated data, only with a different toolset. It also provides the opportunity to use game worlds to reflect on practice, theory and the perceptions of [archaeology].”
  • 429
  • 24 Nov 2022
Topic Review
Global Climate Coalition
The Global Climate Coalition (GCC) (1989–2001) was an international lobbyist group of businesses that opposed action to reduce greenhouse gas emissions and publicly challenged the science behind global warming. The GCC was the largest industry group active in climate policy and the most prominent industry advocate in international climate negotiations. The GCC was involved in opposition to the Kyoto Protocol, and played a role in blocking ratification by the United States. The coalition knew it could not deny the scientific consensus, but sought to sow doubt over the scientific consensus on climate change and create manufactured controversy. The GCC dissolved in 2001 after membership declined in the face of improved understanding of the role of greenhouse gases in climate change and of public criticism.
  • 801
  • 24 Nov 2022
Topic Review
R20 Regions of Climate Action
The R20 - Regions of Climate Action is a non-profit environmental organization founded in September 2011, by former Governor of California , Arnold Schwarzenegger, with the support of the United Nations . R20 is a coalition of sub-national governments, private companies, international organizations, NGOs, and academic & financial institutions. Its mission is to accelerate sub-national infrastructure investments in the green economy to meaningfully contribute to the Sustainable Development Goals (SDGs). The NGO operates at the sub-national level as R20 believes sub-national governments constitute a powerful force for change and are best positioned to take action & implement green projects. R20's efforts are designed to support sub-national governments around the world to develop and finance low-carbon and climate resilient infrastructure projects in the field of renewable energy, energy efficient lighting and waste optimisation.
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  • 24 Nov 2022
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