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To predict pedestrian movement is of vital importance in a wide range of applications. Recently, data-driven models are receiving increasing attention in pedestrian dynamics studies, demonstrating a great potential in enhancing simulation performance. This paper presents a pedestrian movement simulation model based on the artificial neural network, in which two submodels are, respectively, used to predict velocity displacement and velocity direction angle at each time step. Destination information, the pedestrian's historical movement information, neighboring pedestrians, and environmental obstacles within a semicircular-shaped perception area are used as inputs to learn pedestrian movement behavioral rules. In the velocity direction angle submodel, a novel division method on pedestrian's perception area is adopted. Specifically, perception radius is divided into several bands, and perception angle range is divided into a number of sectors, establishing a weighted spatial matrix to represent varied influences of neighboring pedestrians and obstacles. Experiments on two typical scenarios, the unidirectional flow and bidirectional flow in a long straight corridor, were conducted to obtain pedestrian movement datasets. Then, a series of simulation cases were conducted to investigate the proper values for critical parameters, including perception radius, perception angle division, weights of the spatial matrix, and historical movement adoption. In comparison of pedestrian trajectory between simulation results and real data, the mean trajectory error (MTE) and mean destination error (MDE) are, respectively, 0.114 m and 0.171 m in the unidirectional flow scenario, which are, respectively, 0.204 m and 0.362 m in the bidirectional flow scenario. In addition, the fundamental diagram representing density-velocity and density-flow relationships in simulation results agree well with that in real data. The results demonstrate great capacity and credibility of the presented model in simulating pedestrian movement in real applications. [ABSTRACT FROM AUTHOR]

The brachiopods collected from the Kuanyinchiao Beds (Hirnantian, uppermost Ordovician) in Meitan and Zunyi counties, northern Guizhou, include 13 species and one undetermined taxon, dominated by Hirnantia sagittifera (M'Coy, 1851) (which accounts for over one-third of the specimens), together with common Eostropheodonta hirnantensis (M'Coy, 1851). They are assigned to the Hirnantia–Eostropheodonta Community, which probably inhabited a shallow-water, nearshore Benthic Assemblage (BA) 2 to upper BA 3 environment. Population analysis shows that the community was well adapted to this environment after the first phase of the end-Ordovician mass extinction. Representative specimens of all the species are illustrated, and a new species, Minutomena missa, is described herein. The variation in Hirnantia sagittifera was noted in many of previous studies but was not statistically evidenced. Here we have measured representative specimens of that famous species from the major paleoplates and terranes in the world, along with other species assigned to the genus from South China. Having used principal component analysis (PCA), significant variations in the species are documented statistically and revised, and three nominal species, one subspecies, and two morphotypes are now reassigned to Hirnantia sagittifera sensu stricto. UUID: http://zoobank.org/references/3f83fb1e-a6dd-4585-9f9f-9586dad28244 [ABSTRACT FROM AUTHOR]

A series of major geological and biological events which altered the evolutionary processes of whole biosphere occurred during the earth history. Establishing a high-resolution stratigraphic framework and timescale is essential to understand their tempo and causes. High-resolution biostratigraphy remains the most useful approach and forms the basis of dividing the chronostratigraphic system and making the inter-continental and regional correlation. China possesses nearly complete strata from Ediacaran to Quaternary covering wide palaeogeographic regions and containing abundant well-preserved fossils. Traditional biostratigraphy based on sytematic palaeontology of various fossil groups have played an important role in establishing the GSSPs and improving the International and Chinese Stratigraphic Charts. 11 out of 72 establised GSSPs are located in China. Recently, more high-precision geochronology, chemostratigraphy, cyclostrtatigraphy have been applied for stratigraphy and correlation and important advances have been made in some periods. This volume invited Chinese palaeontologists and stratigraphers to summarize the progresses of stratigraphy and timescale from Ediacaran to Quaternary and intercontinental and regional correlation during the last two decades. [ABSTRACT FROM AUTHOR]

Silurian is a period with the shortest duration in Phanerozoic except for the Neogene and Quaternary. It represents an important and unique interval when the biotic diversity recovered quickly after the end-Ordovician mass extinction, different paleoplates or terranes conjoined, big oceans disappeared or narrowed, climate and sea level changed frequently, global biotic provincialism became weaker, some primitive plants started to occupy the land. Silurian is also the first system of which all the chronostratigraphic stratotypes (i.e. the GSSPs) including four series and seven stages were established by the International Subcommission on Silurian Stratigraphy (ISSS). Nonetheless, during the post-GSSP studies conducted by ISSS in the middle 1980s, some Silurian GSSPs were found to have some congenital defects such as no index fossils available that hinder the high resolution subdivision and correlation on a regional or global scale. In this paper, based on the latest development of Silurian study in China, the progress in biostratigraphy, chronostratigraphy, event stratigraphy (such as facies differentiation, heterochrony of black shales, marine red beds, carbonate rocks and reefs), chemostratigraphy, and tectonic stratigraphy (e.g., widespread of the late Silurian rocks in South China and its tectonic implication) are systematically summarized. Some existing problems and the areas to be focused in future work are also discussed. It is suitable for chronostratigraphic study to concentrate not only on the boundary but also doing multidisciplinary analysis on the biotic, chemical, magnetic, environmental, and chronologic aspects, in order to enhance the reliability and the potential for regional and global correlation of a certain GSSP. Some important achievements are expected in these areas in the Silurian study in China: (1) ecostratigraphy and basin analysis of the Llandovery, and the correlation of integrative stratigraphy with a high resolution; (2) establishment of the Wenlock to Pridoli chronostratigraphic framework; (3) the chemo- and magnetic stratigraphy and the age of some key intervals and horizons; (4) further investigation on paleogeography and plate tectonics; and (5) origin and early evolution of the terrestrial ecosystem. Some new breakthroughs might occur in the restudy on some of those problematic GSSPs of some particular series and stages. [ABSTRACT FROM AUTHOR]

It is the first time to document the trilobite Mucronaspis (Songxites) wuningensis and the brachiopod Paromalomena-Aegiromenella Assemblage from the Xinkailing Bed (Hirnantian, uppermost Ordovician) in Taoyuan and Cili counties, northwestern Hunan Province. Synecological analysis shows that this is a deep water shelly fauna of South China during the Hirnantian. It lived on the upper Jiangnan Slope in northwestern Hunan, adjacent to the southeast margin of the Upper Yangtze Region, and belongs to the Hirnantia fauna with cool and deep water, and low diversity affinity, similar to its contemporary shelly faunas from the southern Shaanxi Slope adjacent to the north margin of the Upper Yangtze Region, the northern Chongqing depression (new name), and the Jiangxi-Anhui-Jiangsu gentle slope of the Lower Yangtze Region. Paleoecologically, it could be attributed to the BA 4-5 benthic regime (about 60-150 m deep, and deepest to 200 m), and was significantly different from the trilobite M. (S.) mucronata and the typical Hirnantia fauna while the latters may have habited in BA 2-3 benthic regimes (about 5-60 m deep). A new paleogeographic distribution pattern of the Hirnantian shallow and deep water shelly faunas of South China is herein proposed for the first time. Assuming that the depositional rate was constant in northwestern Hunan during the end Ordovician, the duration of the Xinkailing Bed might be only 12 thousand years according to the thickness of the Wufeng Formation and the absolute age values of those relevant graptolitic biozones. Such a short time interval may indicate that the global environmental change during the crisis was much shorter than previously thought, and its influence on the deep water regime was significantly shorter than that on the shallow water regime. [ABSTRACT FROM AUTHOR]

This paper aims to disclose the resistance features of plate heat exchanger, a common heat transfer device and a major producer of flow resistance. For this purpose, the author examined the flow features within the plate heat exchanger, and established a resistance calculation model for the exchanger. hen, the model was solved through both numerical simulation and mathematical analysis. On this basis, an actual plate heat exchanger was simulated by the model, with the aim to acquire the exchanger resistance and the flow distribution across different paths. The results show that the deviation between the calculation results and the test results was 5.8%; the path flow decreased with the increase in the distance between the path and the inlet; the decline was steep at the beginning, and disappeared at the path sufficiently far away from the inlet. In summary, this research identifies the resistance of plate heat exchanger, and obtains the flow distribution of each path in the exchanger. Suffice it to say that the research findings provide new insights into the resistance calculation of plate heat exchangers in actual engineering. [ABSTRACT FROM AUTHOR]

Silurian brachiopods of Middle Llandovery ( Aeronian) ages are reviewed, and 215 genera are identified here, compared with 109 in the preceding Early Llandovery ( Rhuddanian), indicating a recovery-radiation interval after the end- Ordovician mass extinction. The chief regions in which they are found are the continents of South China, Avalonia- Baltica, Laurentia and Siberia, which were all at tropical latitudes with the exception of Avalonia. In addition, the very large superterrane of Gondwana, although with patchy brachiopod distribution, included temperate faunas, as well as subtropical faunas (in Iran and Afghanistan). Aeronian brachiopods greatly increased in diversity, with dominance of four major groups: orthides and strophomenides (which had flourished previously in the Rhuddanian), pentamerides and atrypides (which became dominant in the Aeronian), and many newly evolved taxa, and occupied deeper water and wider ecological niches (level bottom and reef) than those in the Rhuddanian. Each of the continents has some endemic genera, but there is a greater proportion of them in South China, where some groups (such as the pentamerides and atrypides) are more diverse and others, such as the orthides, are much less common than elsewhere. Affinity indices ( AI) show that two megaunits can be recognized: South China and Avalonia-Baltica-Laurentia ( ABL); Siberia seems to have been loosely connected with ABL and even more loosely to South China presumably because of its geographical separation in the Northern Hemisphere. The separation of South China from the other megaunits is further supported by cluster analysis. [ABSTRACT FROM AUTHOR]

Marine red beds occur frequently in China through geological time. Despite their complex environments, the red beds are found in three depositional settings: 1) oceanic, deep water, as in the Upper Cretaceous of southern Tibet; 2) outer shelf, deeper water, as in the Lower-Middle Ordovician of South China; and 3) inner shelf, shallow water, as in the Silurian and Triassic in South China. The Silurian marine red beds are recurrent in the lower Telychian, upper Telychian, and upper Ludlow. This paper is to document the marine nature of the lower Telychian red beds (LRBs) in the Upper Yangtze Region and to discuss the spatial and temporal distribution of the LRBs and their depositional environments. The LRBs are best developed on the north side of the Cathaysian Oldland, which can be interpreted as the source area. It is inferred that they were deposited during a marine regression, characterized by the lack of upwelling, low nutrition and organic productivity with a decrease of biodiversity and a high rate of sedimentation. The iron-rich sediments may have been transported by rivers on the oldland into the Upper Yangtze Sea, as rates of deposition were rapid enough to counteract normal reducing effect around sediment-water interface. The LRBs are different from the off-shore, deeper water red beds of lower Telychian in Avalonia and Baltica and further from the oceanic, deep water red beds of Upper Cretaceous in southern Tibet chiefly in palaeogeographic settings, biotic assemblages and marine environments. [ABSTRACT FROM AUTHOR]

Abstract: Extinction events usually disrupt palaeobiogeographical patterns, but there have been few detailed studies of the Early Silurian survival–recovery period after the Late Ordovician mass extinction. This paper summarizes and revises published information on the recovery of Early and Late Rhuddanian brachiopod faunas. The global dataset consists of 137 occurrences, 72 genera, and 13 localities of Early Rhuddanian (survival interval), and 271 occurrences, 91 genera, and 26 localities of the Late Rhuddanian (early recovery interval). The data are analyzed using Cluster Analysis, Nonmetric Multidimensional Scaling, and Minimum Spanning Tree using Yule''s Y coefficient and the Raup–Crick coefficient (probabilistic index of similarity). The results display palaeolatitudinal distribution patterns for brachiopods during their survival and recovery. Frequency analysis of the data indicates that cosmopolitan taxa before the mass extinction decreased in their post-extinction distribution. The survivors were mostly confined to one palaeoplate or even one locality in the survival interval, but expanded progressively in the subsequent recovery period. [Copyright &y& Elsevier]

Shell beds in the uppermost Xiangshuyuan Formation and its coeval Upper Shihniulan Formation (Lower Silurian), northern Guizhou, SW China, are interpreted as tempestites occurring on the Upper Yangtze Platform. The shells are dominated by two endemic and transient virgianid (brachiopod) taxa, Paraconchidium shiqianensis and Virgianella glabera, which vary in relative abundance and deposited as fragments of valves with cemented micrite that differs from the surrounding sediment, demonstrating that the shells were not originally preserved in growth positions. The thicknesses of individual shell layers vary from ten centimeters to more than four meters. Shells had been strongly stirred up by high-energy currents, mainly caused by ocean storm events and probably related to the profile of the geographic shape of the coastline. Fragmentation of shells, in particular, their thinning anterior parts of ventral and dorsal valves are more intensive. The benthic assemblages are from lower BA2 to upper BA3 in depth, assigned to near shoal belt in geographic background. Breakage and stacking density are of the indexes of proximal and distal transportations. Northern Guizhou was located within the lower latitudes of the Southern Hemisphere during the Silurian time, and obviously affected the depth of the virgianid inhabitation. Most of these shells were disturbed repeatedly by surges. It is inferred that on average, several ten thousand years of growth of shells were required for development of shell layers, followed by storm disruption. [ABSTRACT FROM AUTHOR]

Sixteen species from the Lower Silurian (mostly Aeronian and rarely Telychian) of South China have been assigned previously to the brachiopod family Pentameridae, mainly to the genus Pentamerus. Study of intrapopulation variation suggests that 13 species from the upper Aeronian Lojoping Formation of the Yichang area, western Hubei Province, can be synonymized with Sulcipentamerus dorsoplanus, the most abundant pentamerid species of South China but confined to the Yichang area. The conspicuously high and obtuse ventral umbo, strong ventribiconvexity and a sulcate anterior commissure warrant genus status for Sulcipentamerus, independent of Pentamerus. True Pentamerus is rare in South China, known only from upper Aeronian rocks of Guizhou Province. Multivariate analyses indicate that Aeronian pentameride brachiopods of South China are characterized by a high level of provincialism, distinct from those of Laurentia. Also, the Aeronian pentamerides of South China or Laurentia have a low degree of similarity to those of Baltica, Siberia, Avalonia, Kazakhstan and other palaeotropically located plates or terranes. Besides South China and Laurentia, the pentamerides of other palaeotropical regions constituted a relatively tight cluster. This suggests that the palaeogeographical positions of South China and Laurentia only allowed limited or periodic faunal exchange of these generally large-shelled brachiopods adapted to living in relatively shallow, warm waters. [ABSTRACT FROM AUTHOR]

Examines the relation between central Guizou and Yichang uplifts present in central Guizou to western Hubei in China. Stratigraphic evidence of the uplifts; Mechanism of the central Guizou and Yichang uplifts.

The temporal and spatial distribution of Hirnantian brachiopod faunas are reviewed based on a new, comprehensive dataset from over 20 palaeoplates and terranes, a revised correlation scheme for Hirnantian strata and numerical methods including network analysis. There were two successive evolutionary faunas: 1. widespread and diachronous Hirnantia Fauna related to the glacial acme in the early−mid Hirnantian, including shallow, deeper and deep-water communities that diversified in much more complicated environmental conditions than hitherto envisaged; and 2. Edgewood-Cathay Fauna (new term) thrived during post-glacial, warmer, shallow-water regimes with both carbonate and siliciclastic facies from low latitudes in the late Hirnantian−early Rhuddanian. The two survival faunas occur in the same order in different regions, immediately following the first and second phases of the Hirnantian crisis, respectively. This faunal succession records two climatic perturbations, one with a glaciation, associated with climatic cooling and a global low-stand, during which the Hirnantia Fauna flourished, and a second characterized by melting ice, global warming, and sea-level rise (with global anoxia), aligned to the development of the Edgewood-Cathay Fauna and the repopulation of the seas by many animals adapted to warmer water, e.g., those in metazoan reefs, massive tabulates, and sponges. Changes in many properties of the Hirnantia Fauna may have resulted from the heterogeneity of global climate change in time and space; contrasts in the Edgewood-Cathay faunas record differences between carbonate and siliciclastic deposition, respectively, at low latitudes. Intense climate changes, sea-level fluctuations, and oceanographic ventilation and anoxia, had important roles in brachiopod evolution through the Hirnantian extinctions as first taxa confined to warm-water and then cool-water conditions were the main victims. During the Hirnantian, higher originations of new taxa may have been a response to crises, which increased the rate of phyletic evolution due to extreme climatic conditions. [ABSTRACT FROM AUTHOR]

The article presents the authors' comments on the End Ordovician extinction event in Hirnantian brachiopod fauna. A chart and a graph representing the Ordovician-Silurian transition is presented. It reflects that correlation of a trough in diversity with a peak in outcrop area can be deduced from the end Ordovician. A large amount of data on Hirnantian brachiopods has been collected due to growing interest in the relationship between glacially driven environmental change and the fauna.

Richly fossiliferous Hirnantian shelly strata of near‐shore facies in northern Guizhou, South China, known as the Kuanyinchiao Formation, superbly record glacioeustatic sea‐level fluctuations and benthic faunal turnover. Recent studies of the temporal and spatial distribution of these carbonates and shelly fossils permit a critical stratigraphic revision and establishment of a robust regional stratigraphic correlation. The formation is revised to include three informal subdivisions, that is, units A, B, and C, in ascending order. Unit B of the formation typically is dominated by peloidal or oolitic grainstones, and unit C is composed of skeletal wackestone and calcareous mudstone, both units sharing distinctive coral and brachiopod faunas. This contrasts sharply with unit A of the formation, consisting of mudstone, silty mudstone, or calcareous mudstone, that yields the cool‐water Hirnantia fauna and associated coral fauna. In view of the presence of carbonate ooids and peloids, rugose corals, and a distinctive brachiopod assemblage, all indicative of warm‐water conditions, unit B, as well as unit C yielding the same shelly fauna, is interpreted as representing postglacial sedimentation immediately following the major Hirnantian glaciation, thus marking a significant climatic shift. Similar warm‐water carbonate rocks have been recognized in a number of regions along the margin of the Qianzhong Oldland, including Bijie, Renhuai, Tongzi, and Fenggang of northern Guizhou. Such a vast distribution area of these rocks indicates that postglacial carbonates are more widespread on the Yangtze Platform of South China than previously thought, providing a rare window into rocks and fossils of the survival interval immediately following the extinction event associated with the Hirnantian glacial episodes. [ABSTRACT FROM AUTHOR]

'Strophodontoid' brachiopods represented the majority of strophomenide brachiopods in the Silurian and Devonian periods. They are characterized by denticles developed along the hinge line. The evolution of denticles correlated with the disappearance of dental plates and teeth and were already present when the clade originated in the Late Ordovician. Specimens of Eostropheodonta parvicostellata from the Kuanyinchiao Bed (early–middle Hirnantian, uppermost Ordovician) in the Hetaoba Section, Meitan, Guizhou Province, South China, display clear fossil population variation, during a process of loss of dental plates and the development of denticles. Three phenotypes of E. parvicostellata are recognized in a single fossil bed, likely heralding a speciation process. Non‐metric multidimensional scaling (NMDS) based on five key characters of genera of the Family Leptostrophiidae shows a much wider morphospace for Silurian genera than for those in the Devonian. Phylogenetic analysis of the Family Leptostrophiidae supports the NMDS analysis and mostly tracks their geological history. The fossil population differentiation in E. parvicostellata discovered between the two phases of the Late Ordovician mass extinction event (LOME) linked to a major glaciation, suggests a Hirnantian origination of the 'strophodontoid' morphology, and links microevolutionary change to a macroevolutionary event. [ABSTRACT FROM AUTHOR]

Classification of extinction events and their severity is generally based on taxonomic counts. The ecological impacts of such events have been categorized and prioritized but rarely tested with empirical data. The ecology of the end Ordovician extinction and subsequent biotic recovery is tracked through abundant and diverse brachiopod faunas in South China. The spatial and temporal ranges of some 6500 identified specimens, from 10 collections derived from six localities were investigated by network and cluster analyses, nonmetric multidimensional scaling and a species abundance model. Depth zonations and structure of brachiopod assemblages along an onshore-offshore gradient in the late Katian were similar to those in the latest Ordovician–earliest Silurian (post–extinction fauna). Within this ecological framework, deeper-water faunas are partly replaced by new taxa; siliciclastic substrates continued to be dominated by the more ‘Ordovician’ orthides and strophomenides, shallow-water carbonate environments hosted atrypides, athyridides and pentamerides, with the more typical Ordovician brachiopod fauna continuing to dominate until the late Rhuddanian. The end Ordovician extinctions tested the resilience of the brachiopod fauna without damage to its overall ecological structure; that commenced later at the end of the Rhuddanian. [ABSTRACT FROM AUTHOR]

Precise wind power prediction (WPP) can address the issue caused by large-scale wind power grid integration to the power system operation. Most WPP research focus on the randomness and high volatility problem of wind power but ignore the time-series distribution shift (TSDS) problem. To solve the TSDS issue, this study proposes a novel hybrid model that incorporates complementary ensemble empirical mode decomposition (CEEMD), time-series distribution period division (TSDPD) and adaptive distribution-matched GRU (ADMGRU). First, CEEMD is utilized to decompose the nonstationary data into in sub-sequence, reducing complexity and randomness. Second, TSDPD is employed to automatically identify the underlying temporal segments within wind power sequence by maximizing discrepancies in distribution information between two periods, determining the quantity and respective boundaries of periods. Finally, ADMGRU, comprising Pre-train and Boosting-based importance assessment components, learns prediction model accurately by dynamically matching distribution periods. The former component initializes predictive model parameters and the latter learns the importance of each hidden state to assigns corresponding weights to different distributions. Numerous comparative experiments demonstrate the CEEMD-TSDPD-ADMGRU hybrid model surpasses existing popular models. Especially in spring scenario, compared with other four advanced models, the maximum reduction in MAE and RMSE are 54.64 % and 73.33 %, respectively. • A hybrid model (CEEMD-TSDPD-ADMGRU) is proposed considering the time-series distribution shift issue in wind power. • Decompose nonstationary data into subsequences by CEEMD to reduce complexity and randomness. • TSDPD method is proposed to divide distribution segments of wind data. • ADMGRU is proposed to dynamically match distribution periods and achieve prediction. • CEEMD-TSDPD-ADMGRU outperforms other state-of-art methods in prediction accuracy and computational efficiency. [ABSTRACT FROM AUTHOR]

Late Ordovician strophomenide brachiopods (superfamilies Strophomenoidea and Plectambonitoidea) from the upper Changwu Formation (mid Ashgill, late Katian) of Jianglütang, Chun’an County, western Zhejiang Province, consist of ten genera and 12 species. Five new species of three new genera are recognized: Chunanomena triporcata, Chunanomena sembellina, Cheramomena subsolana, Lateriseptomena modesta, and Lateriseptomena rugosa. The strophomenide brachiopods from the upper Katian strata described in this study and those from the border region of Zhejiang and Jiangxi provinces reported in previous work contain 16 strophomenoid and 12 plectambonitoid genera, and most of the strophomenoids are endemic to South China. Numerical analysis of well-documented late Katian strophomenide brachiopod faunas indicates a strong provincialism, characterized by the highly distinct North American province (Laurentia), the South China-Kazakhstan province, and the Avalonia-Baltica province (Wales, Belgium and Sweden). Surprisingly, the Girvan district of Scotland, which was a peri-Laurentian terrane during the Ordovician, contains a late Katian brachiopod fauna that is more closely related to the contemporaneous brachiopods of Avalonia-Baltica than to those of North America. [ABSTRACT FROM AUTHOR]

Due to the lack of historical data, accurate prediction is a great challenge for newly constructed wind farms (NWFs). How to guarantee satisfactory prediction accuracy with limited data has become a bottleneck issue in wind power prediction (WPP). To solve the few-shot learning problem in NWFs, a novel multi-gradient evolutionary deep learning neural network (EATDLNN) prediction model is proposed, which incorporates the time-series GAN (TimeGAN) and multivariate variational mode decomposition (MVMD) method. TimeGAN adds an auto-encoder network and a supervised loss function to GAN, which enables it to capture the dynamic time series correlation characteristics of wind data and generate high-quality samples. MVMD is then employed to simultaneously decompose nonstationary sequences. In the EATDLNN prediction model, an evolution-based multi-gradient training approach is proposed to train the DLNN by integrating three gradient descent methods (i.e., Adam, MBGD-Momentum, RMSprop). Compared with the traditional single-gradient training approach, the multi-gradient training approach provides different gradient descent paths and the gradient can adaptively choose to update towards the path with the smallest error based on the evolutionary framework, which can help the model jump out of the local optimum and enhance the generalization ability. Massive experiments prove the excellent performance of the proposed method, especially in one-step prediction, the root mean square errors reduce by 79.40%∼91.05% compared with other state-of-the-art methods. • A novel multi-gradient evolutionary training method for deep learning prediction model is proposed. • Time-series generative adversarial network is proposed to generate high-quality wind data. • Multivariate variational mode decomposition method is employed to simultaneously decompose the nonstationary wind data. • The proposed approach outperforms other state-of-art methods in addressing few-shot wind power prediction in newly constructed wind farms. [ABSTRACT FROM AUTHOR]

A large brachiopod fauna collected through the upper Wanyaoshu Formation (middle Hirnantian), West Yunnan, China displays, for the first time, a vertical transition within the Hirnantia fauna. The inner to mid‐shelf Fardenia–Hirnantia association segues into the deeper water Aegiromena–Anisopleurella association during the Metabolograptus persculptus marine transgression. This transition parallels the pattern apparent in onshore–offshore gradients within the Hirnantian, imitating Walther's Law for facies, instead predicting the seaward transitions between community types within a single transgressive sequence. In addition, large‐sized brachiopods such as Hirnantia and Eostropheodonta become rarer and small‐sized brachiopods, for example, Aegiromena and Anisopleurella more common. It is a rare opportunity to view transformations in community composition and structure within the Hirnantia fauna together with changes in both the size of individuals and populations (from large to small) during the transgression. [ABSTRACT FROM AUTHOR]

• Segment imbalance regression (SIR) is proposed to address sample imbalance. • SIR is improved by optimizing hyperparameters with CSO. • Wind series is decomposed by EEMD to improve stability. • TSA-BiGRU model is proposed to extract implicit temporal relation information. • The proposed hybrid model outperforms other state-of-the-art methods. Randomness and intermittency are common challenges in wind power prediction. Most studies focus on randomness but usually ignore the intermittency of wind power that leads to sample imbalance and impairs prediction accuracy. To address the sample imbalance problem, a segment imbalance regression (SIR) method with crisscross optimization (CSO) is proposed to proactively dig and utilize the imbalance nature of samples. By investigating the interactions among adjacent samples, SIR is employed to adaptively assign different learning weights to each sample. SIR focuses on the training samples within the segment while retaining useful information outside, and thus can facilitate the gradient descend process and achieve better training performance. On this basis, aiming to extract more feature information, a novel combination network is constructed by integrating two networks, i.e., Temporal self-attention network (TSA) with temporal self-correction and bidirectional gate recurrent unit (BiGRU) with bi-direction temporal memory respectively. The sequence features of samples are first obtained by ensemble empirical mode decomposition (EEMD) as the input of the combination network, and then the SIR-CSO method is used to train the TSA-BiGRU network and enhance the adaptive learning ability. Massive experiments are conducted, and the results demonstrate the excellent performance of SIR and the superiority of the combination network. Especially in three-step prediction, the root mean square errors of the proposed model reduce 38.97%∼47.04% compared with other state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Marine red beds (MRBs) occur in many locations in the world during the Telychian Stage but it is unclear how they were related with the highly dynamic Silurian Earth system. To address this question, we conducted a case study involving geochronology, palaeogeographic reconstruction, facies analysis and sea-level history of the middle Telychian MRBs on the western Yangtze Platform of South China. Their distribution pattern indicates that the clastic MRBs owe their origin to the nearby oldlands. Facies analysis indicates that rocks during the study interval generally fall into three depositional belts: shallow subtidal, deep subtidal and shaly basinal belts. A chronostratigraphic framework constrained by both biostratigraphic data and eustatic events shows that, during the early Monoclimacis crenulata interval, olive-gray strata dominated both shallower (shallow and deep subtidal belts) and deeper (shaly basinal belt) settings, while distribution of the MRBs was restricted to deeper waters (shaly basinal belt) on the open-sea side of the platform. This situation changed after the middle M . crenulata interval when the MRB deposition was dominant in both shallower and deeper settings. The diachronous onset pattern of the MRBs coincided with prominent transitions in climatic conditions (from cooler to warmer), eustatic states (from regression to transgression), benthic faunas (decline of normal marine fauna and development of euryhaline assemblages) and reduced primary productivity in the shelf settings, most likely indicative of a change between different oceanic modes. Comparative studies suggest that, the widespread Telychian MRBs in both shallow and deeper water settings owe their origin to a very low organic carbon burial rate, which could be results of higher oxygen content in the ocean water and lower primary productivity. [ABSTRACT FROM AUTHOR]

In this study, we analyze the deficiencies of specific frictional resistance in heating engineering. Based on economic specific frictional resistance, we put forward the concept of comprehensive specific frictional resistance, which considers the multiple factors of technology, economy, regulation modes, pipe segment differences, and medium pressure. Then, we establish a mathematical model of a heating network across its lifespan in order to develop a method for determining the comprehensive specific frictional resistance. Relevant conclusions can be drawn from the results. As an application, we have planned the heating engineering for Yangyuan County in China, which demonstrates the feasibility and superiority of the method. [ABSTRACT FROM AUTHOR]

The distribution pattern of early Telychian ( turriculatus-crispus graptolite biozone) red beds in the Eastern Yangtze Platform of South China is reconstructed based on regional geologic data. The red beds are developed in three areas, which are separated by regions without red deposition. The distribution pattern indicates that the Cathaysian Oldland was the provenance of sediment rich in ferric oxides, which are essential for the formation of red beds. Silurian marine siliciclastic red beds, both in China and worldwide, tended to develop during times of relatively low sea level. Coeval hematitic oolites that formed far from the coast may record a change from reducing to oxidizing conditions in the ocean. Furthermore, it is likely that a fall in global sea level, a transition from reducing to oxidizing conditions in the ocean, and a cooling climate, all of which were closely related to the early Telychian Valgu Event, promoted the global development of marine red beds during this period. [ABSTRACT FROM AUTHOR]

Abstract: In the immediate aftermath of global extinctions, organisms were normally much smaller than those prior to these events. This ‘Lilliput Effect’ can be subdivided into two types: 1) a specific type, following the original definition of the effect which targets species-level taxa associated with inhospitable environments, and 2) a more general type, related to the reactions of higher-rank taxa above the species-level. The body sizes of brachiopods from South China through the Ordovician and Silurian transition (Late Katian, Hirnantian, and earliest Rhuddanian) are compared at generic, superfamilial, ordinal, and class levels. The results indicate that the body sizes of the taxa of lower rank (e.g. genus-level) are highly variable within these different intervals. The type of evidence for the Lilliput Effect through the end Ordovician mass extinction is thus quite different from that of the end Permian mass extinction probably reflecting differences in the intensity of these two major bioevents. However, the relationships between the contrasting trends in body-size change of some taxa of higher rank (e.g. at the ordinal-level) and the relative dominance of these taxa in the latest Ordovician and earliest Silurian suggest that the brachiopods of the two major Ordovician groups, the strophomenoids and orthoids, adopted different survival strategies during and immediately after the crisis from those of the pentamerides and rhynchonellides, that were common in Silurian assemblages. [Copyright &y& Elsevier]