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Risk mapping of wildlife-vehicle collisions across thestate of Montana,USA:a machine-learning approach forimbalanced data along rural roads

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Transportation Safety and Environment 2024年第3期6卷 124-132页

作者： Matthew bell Yiyi Wang rob Ament Western Transportation Institute Montana State University2327 University WayBozemanMT 59717USA School of Engineering San Francisco State University1600 Holloway AveSan FranciscoCA 94132USA

Wildlife-vehicle collisions(WVCs)with large animals are estimated to cost the USA over 8 billion USD in property damage,tens of thousands of human injuries and nearly 200 human fatalities each *** WVCs occur on rural roads and are not collected evenly among road segments,leading to imbalanced *** are a disproportionate number of analysis units that have zero WVC cases when investigating large geographic areas for collision *** units with zero WVCs can reduce prediction accuracy and weaken the coefficient estimates of statistical learning *** study demonstrates that the use of the synthetic minority over-sampling technique(SMOTE)to handle imbalanced WVC data in combination with statistical and machine-learning models improves the ability to determine seasonal WVC risk across the rural highway network in Montana,*** array of regularized variables describing landscape,road and traffic were used to develop negative binomial and random forest models to infer WVC rates per 100 million vehicle miles *** random forest model is found to work particularly well with SMOTE-augmented data to improve the prediction accuracy of seasonal WVC ***-augmented data are found to improve accuracy when predicting crash risk across fine-grained grids while retaining the characteristics of the original *** analyses suggest that SMOTE augmentation mitigates data imbalance that is encountered in seasonally divided WVC *** research provides the basis for future risk-mapping models and can potentially be used to address the low rates of WVCs and other crash types along rural roads.

关键词： wildlife-vehicle collisions machine learning SMOTE negative binomial risk mapping

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Carbon dioxide enrichment affected flower numbers transiently and increased successful post-pollination development stably but without altering final acorn production in mature pedunculate oak (Quercus robur L.)

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Journal of Forestry Research 2024年第4期35卷 1-12页

作者： Ryan McClory Richard H.Ellis Martin Lukac Jo Clark Carolina Mayoral Kris M.Hart Andrew R.G.Plackett A.rob MacKenzie School of Agriculture Policy and DevelopmentUniversity of ReadingAgricultureEarley GateWhiteknights RoadPO Box 237Reading RG66EUUK Faculty of Forestry and Wood Sciences Czech University of Life Sciences PraguePrague 165000Czechia Future Trees Trust Harwell Innovation CentreBuilding 173Curie AvenueHarwellOxford OX110QGUK birmingham Institute of Forest Research University of BirminghamEdgbastonBirmingham B152TTUK School of biosciences University of BirminghamEdgbastonBirmingham B152TTUK School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirmingham B152TTUK

Acorn production in oak(Quercus spp.)shows considerable inter-annual variation,known as masting,which provides a natural defence against seed predators but a highly-variable supply of acorns for uses such as in commercial tree planting each *** emissions of greenhouse gases have been very widely reported to influence plant growth and seed or fruit size and quantity via the‘fertilisation effect’that leads to enhanced *** examine if acorn production in mature woodland communities will be affected by further increase in CO_(2),the contents of litter traps from a Free Air Carbon Enrichment(FACE)experiment in deciduous woodland in central England were analysed for numbers of flowers and acorns of pedunculate oak(Quercus robur L.)at different stages of development and their predation levels under ambient and elevated CO_(2) ***-annual variation in acorn numbers was considerable and cyclical between 2015 and 2021,with the greatest numbers of mature acorns in 2015,2017 and 2020 but almost none in *** numbers of flowers,enlarged cups,immature acorns,empty acorn cups,and galls in the litter traps also varied amongst years;comparatively high numbers of enlarged cups were recorded in 2018,suggesting *** at this site is a fruit maturation masting species(i.e.,the extent of abortion of pollinated flowers during acorn development affects mature acorn numbers greatly).Raising the atmospheric CO_(2) concentration by 150μL L^(−1),from early 2017,increased the numbers of immature acorns,and all acorn evidence(empty cups+immature acorns+mature acorns)detected in the litter traps compared to ambient controls by 2021,but did not consistently affect the numbers of flowers,enlarged cups,empty cups,or mature *** number of flowers in the elevated CO_(2) plots’litter traps was greater in 2018 than 2017,one year after CO_(2) enrichment began,whereas numbers declined in ambient *** with CO_(2) also increased the number o

关键词： Quercus robur L. Acorns Masting Pedunculate oak Carbon dioxide

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Drought Tolerance and Recovery of the Sedge Carex planostachys (Cyperaceae) from Central Texas Woodlands

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American Journal of Plant Sciences 2024年第9期15卷 746-765页

作者： E. rob Wayne Oscar William Van Auken Natural Sciences Department St. Philips College San Antonio USA Department of Integrative biology The University of Texas at San Antonio San Antonio USA

Carex planostachys Kunze (Cyperaceae, Cedar sedge) is an herbaceous species in a genus commonly inhabiting mesic or hydric habitats. Carex planostachys is found in arid and semi-arid Juniperus woodlands. Arid conditions impose survival challenges to plants in dry areas. Some plants have plasticity responses to soil water content and continued normal though reduced functions through droughts, but most herbaceous plants do not survive. Limited previous studies have suggested C. planostachys is tolerant of drought. Physiological responses of C. planostachys from Juniperus woodlands was examined is this study to determine how long plants could survive without water and if they are capable of recovery from very negative water potentials beyond what is considered the permanent wilting point for most herbaceous plants. Plants were placed in pots in partial shade in this experiment. Water loss from the soil with plants was an inverse 2nd order polynomial function with soil water decreasing from 32% to 8% by day 28 of the study. Leaf water potential was also an inverse 2nd order polynomial function but did not decline significantly until 14 days without watering. Leaf water potential was −10.0 MPa after 35 days without watering. Non-watered plants Anet, (photosynthetic rate) was significantly lower compared to the water treatment by day 21 as was stomatal conductance and transpiration. When non-watered plants were watered after 21, 28 or 35 days, full recovery of physiological responses occurred within 7 days. The length of time that C. planostachys was able to withstand drought was greater than the annual trends in lack of precipitation during springtime in this area. Carex planostachys can photosynthesize at water stress between −8 and −10 MPa. Carex planostachys drought and shade tolerance enables it to occupy an understory niche devoid of other herbaceous plants.

关键词： CO2 Uptake Conductance Gas Exchange Photosynthesis Respiration Transpiration Water Stress Water Potential.

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乡村旅游精英公共服务动机的结构维度研究

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旅游学刊 2024年第9期39卷 91-105页

作者：徐少癸韩佳钰陈思榕 rob LAW 章牧福建师范大学文化旅游与公共管理学院暨南大学深圳旅游学院南洋理工大学黄金辉传播与信息学院澳门大学亚太经济与管理研究所澳门大学工商管理学院

乡村旅游精英在乡村振兴、消除贫困、促进乡村旅游可持续发展等方面发挥着至关重要的作用。然而，作为中国旅游研究领域的热点议题，乡村旅游精英的动机研究却往往被简单化和边缘化。因此，文章基于中国乡土文化背景，聚焦乡村旅游精英... 详细信息

乡村旅游精英在乡村振兴、消除贫困、促进乡村旅游可持续发展等方面发挥着至关重要的作用。然而，作为中国旅游研究领域的热点议题，乡村旅游精英的动机研究却往往被简单化和边缘化。因此，文章基于中国乡土文化背景，聚焦乡村旅游精英这一特定群体，利用扎根理论对乡村旅游精英公共服务动机的结构维度进行探索性研究。研究发现，乡村旅游精英公共服务动机由乡土情结、公共利益承诺、社会认可与支持、自我奉献精神和政策制定吸引力5个维度组成。其中，公共利益承诺、自我奉献精神和政策制定吸引力3个维度具有普适性，乡土情结和社会认可与支持则是文章基于中国乡土社会背景发现的新维度。乡村旅游精英公共服务动机是一个复杂的多维结构体系，各维度相互关联、相互影响，共同构成了乡村旅游精英公共服务动机的驱动因素。以上结论对乡村旅游精英公共服务动机研究具有一定的理论贡献，同时也为乡村旅游目的地管理、评估乡村旅游精英提供了针对性建议。

关键词：乡村旅游精英公共服务动机乡村旅游乡村振兴扎根理论

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black hole shadows in Einstein-bel-robinson gravity

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Chinese Physics C 2024年第5期48卷 272-283页

作者： b.Hamil b.C.Lütfüoğlu Laboratoire de Physique Mathématique et Subatomique Facultédes Sciences ExactesUniversitéConstantine 1ConstantineAlgeria Department of Physics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

Gravity models given by higher-order scalar curvature corrections are believed to bear important consequences. Einstein-bel-robinson (EbR) gravity with quartic curvature modification motivated Sajadi et al. to explore static spherically symmetric black hole solutions using perturbative methods. In this study, inspired by their work, we investigate AdS black hole shadows in EbR gravity and demonstrate how the gravity parameter alters the energy emission rate. Finally, we address the same problem in the presence of plasma, because the black holes are thought to be surrounded by a medium that changes the geodesic of photons.

关键词： black hole shadows Einstein-bel-robinson gravity plasma

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Water Vapor Information from Satellite and Its Applications

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Advances in Atmospheric Sciences 2024年第1期41卷 188-189页

作者： b.J.SOHN School of Earth and Environmental Sciences Seoul National UniversitySeoul 08826Korea

Water vapor is a critical component of the hydrological cycle because it plays a vital role in transporting water from one part of the cycle to *** vapor evaporated from surfaces such as oceans,lakes,and rivers conden... 详细信息

关键词： motion oceans lakes

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Soils in extraterrestrial space: Need for studies under microgravity

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Pedosphere 2024年第1期34卷 13-14页

作者： M.b.KIRKHAM Department of Agronomy Kansas State UniversityManhattan KS 66506USA

With the increased interest of plants in space, gravity cannot be ignored when studying soil-plant-water relations. Therefore, it is important to understand the water relations of soils under zero gravity in space or under reduced gravity on the Moon or Mars. This paper outlines the problems of moving water in soils under zero gravity or microgravity, as well as growing plants in these soils. It is suggested that microgravity experiments could be done on Earth using both soils and plants. Results from such experiments could be used to grow plants when mankind establishes bases on the Moon and Mars.

关键词： soils soil bases

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探索DNA数据驱动器

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科技纵览 2024年第3期 30-36,4页

作者： rob Carlson 不详

我们每天都会产生很多数据,包括电子邮件、文本、照片和社交媒体帖子等。虽然这些内容大多不值得保存,但每天我们都在默默地作出不删除这些数据的决定。我们把它们保存在某个地方,可能是手机上、电脑硬盘上或者云上,最终它们都会被存档... 详细信息

我们每天都会产生很多数据,包括电子邮件、文本、照片和社交媒体帖子等。虽然这些内容大多不值得保存,但每天我们都在默默地作出不删除这些数据的决定。我们把它们保存在某个地方,可能是手机上、电脑硬盘上或者云上,最终它们都会被存档,大多数情况下是在磁带上。此外,现在各种设备和传感器都将数据传输到网络上,汽车、飞机和其他交通工具的数据也要存储以备后用。物联网上的数十亿物品都会产生数据,所有这些信息都需要存储在某个地方。

关键词：电子邮件电脑硬盘物联网数据传输其他交通工具社交媒体传感器

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CompactChain:an efficient stateless chain for UTXO-model blockchain

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Frontiers of Computer Science 2024年第2期18卷 167-179页

作者： b Swaroopa REDDY T Uday Kiran REDDY Department of Electrical Engineering Indian Institute of Technology HyderabadHyderabadTelangana 502285India

In this work,we propose a stateless blockchain called CompactChain,which compacts the entire state of the UTXO(Unspent Transaction Output)based blockchain systems into two RSA *** first accumulator is called Transaction Output(TXO)commitment which represents the TXO *** second one is called Spent Transaction Output(STXO)commitment which represents the STXO *** this work,we discuss three algorithms:(i)To update the TXO and STXO commitments by the *** miner also provides the proofs for the correctness of the updated commitments;(ii)To prove the transaction’s validity by providing a membership witness in TXO commitment and non-membership witness against STXO commitment for a coin being spent by a user;(iii)To update the witness for the coin that is not yet spent;The experimental results evaluate the performance of the CompactChain in terms of time taken by a miner to update the commitments and time taken by a validator to verify the commitments and validate the *** compare the performance of CompactChain with the existing state-of-the-art works on stateless *** shows a reduction in commitments update complexity and transaction witness size which inturn reduces the mempool size and propagation latency without compromising the system throughput(Transactions per second(TPS)).

关键词： stateless blockchain RSA Accumulator STXO commitment TXO commitment UTXO Non-interactive Proof of Exponentiation(NI-PoE) Transactions per second(TPS)

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Closing the Experiment-Modeling-Perturbation Loop in Whole-brain Neuroscience

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Neuroscience bulletin 2024年第8期40卷 1212-1214页

作者： Misha b.Ahrens Janelia Research Campus Howard Hughes Medical InstituteAshburnVAUSA

Understanding the mechanisms by which the central nervous system processes information,forms memories,makes decisions,and executes actions is a challenging *** is an interdisciplinary field in which cell biology,anatomy,network theory,and other scientific disciplines come together to jointly push our knowledge of brain function forward.

关键词： execute knowledge jointly

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