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The Early-middle Triassic Supervolcano in the Yangtze Block,South China and associated obstacles to biotic recovery

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Geoscience Frontiers 2024年第1期15卷 69-83页

作者： Haifeng Chen Hao Zou mSantosh Huawen Cao Franco Pirajno Changcheng Huang mingcai Hou State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengduSichuan 610059China College of Earth Science Chengdu University of TechnologyChengduSichuan 610059China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Department of Earth Science University of AdelaideAdelaideSA 5005Australia Yonsei Frontier Lab Yonsei UniversitySeoulSouth Korea Centre of Exploration Targeting The University of Western Australia35 Stirling HighwayCrawleyWA 6009Australia

The end-Permian mass extinction was one of the major global crises spanning the entire Early Triassic or *** of volcanos were one of the factors that delayed the biotic recovery after this *** eruptions can cause catastrophic effects on global environment,climate,and *** we investigate the tuff layers from Early-middle Triassic boundary in the Yangtze Block and identify a supervolcano eruption *** zircon U-Pb ages of the section-Langdai,section-Daijiagou and section-Longmendong tuff samples are 247.1±1.9 ma,247.6±2.0 ma and 247.7±1.7 ma,*** ages mark the Olenekian-Anisian *** zircon grains from the tuff layers have negativeεHf(t)(-15.3 to-0.8),two-stage Hf model(TDm2)ages(1.7 to 2.2 Ga)and display high-δ18O values(mostly>10‰).Clay minerals and quartz dominate the rock *** whole rock compositions show that the tuff layers were derived from magma of intermediate to felsic composition,which formed by the remelting of Paleoproterozoic materials of continental *** volcanic eruption site is located in the Jinshajiang-Ailaoshan-Song ma suture zone in the southwestern margin of the Yangtze Block.A combination of the closure of the Paleo-Tethys Ocean Basin and the collision of the Indochina Block and South China contributed to the eruption,which was a supervolcano eruption under the active continental margin arc *** speculate that this supervolcano eruption might have contributed to the delayed biotic recovery after the end-Permian mass extinction.

关键词： Early-middle Triassic Tuff layer Supervolcano Yangtze Block Biotic recovery

Towards climate resilient urban energy systems: a review

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National Science Review 2021年第3期8卷 159-176页

作者： Vahid m.Nik A.T.D.Perera Deliang Chen Division of Building Physics Department of Building and Environmental Technology Lund University Institute for Future Environments(IFE) Queensland University of Technology(QUT) Regional Climate Group Department of Earth SciencesUniversity of Gothenburg Division of Building Technology Department of Architecture and Civil Engineering Chalmers University of Technology Solar Energy and Building Physics Laboratory(LESO-PB) Ecole Polytechnique Federale de Lausanne(EPFL) Urban Energy Systems Laboratory

Climate change and increased urban population are two major concerns for *** towards more sustainable energy solutions in the urban context by integrating renewable energy technologies supports decarbonizing the energy sector and climate change mitigation.A successful transition also needs adequate consideration of climate change including extreme events to ensure the reliable performance of energy systems in the long *** review provides an overview of and insight into the progress achieved in the energy sector to adapt to climate change,focusing on the climate resilience of urban energy *** state-of-the-art methodology to assess impacts of climate change including extreme events and uncertainties on the design and performance of energy systems is described and *** resilience is an emerging concept that is increasingly used to represent the durability and stable performance of energy systems against extreme climate ***,it has not yet been adequately explored and widely used,as its definition has not been clearly articulated and assessment is mostly based on qualitative *** study reveals that a major limitation in the state-of-the-art is the inadequacy of climate change adaptation approaches in designing and preparing urban energy systems to satisfactorily address plausible extreme climate ***,the complexity of the climate and energy models and the mismatch between their temporal and spatial resolutions are the major limitations in linking these ***,few studies have focused on the design and operation of urban energy infrastructure in terms of climate *** the occurrence of extreme climate events and increasing demand for implementing climate adaptation strategies,the study highlights the importance of improving energy system models to consider future climate variations including extreme events to identify climate resilient energy transition pathways.

关键词： climate resilience climate change adaptation urban energy systems renewable energy extreme events decentralized generation

Comment on “Relativistic atomic data for W XLVII” by S. Aggarwal et al. [Chin. Phys. B 24(2015)053201]

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Chinese Physics B 2015年第12期24卷 291-294页

作者： Kanti m.Aggarwal Astrophysics Research Center School of Mathematics and Physics Queen's University Belfast

Recently, S. Aggarwal et al. [Chin. Phys. B 24（2015） 053201] reported energy levels, radiative rates, and lifetimes for the lowest 148 levels belonging to the 3s^23 p, 3s3p^2, 3s^23d, 3s3p3d, 3p^3, 3p^23d, 3s3d^2, 3p3d^2, and 3d^3 configurations of Al-like tungsten. While their calculated energies for the levels and the radiative rates for transitions are correct, the reported results for lifetimes are completely wrong. According to our calculations, errors in their reported lifetimes are up to 14 orders of magnitude for over 90% of the levels. Here we report the correct lifetimes and explain the reasons for discrepancies.

关键词： energy levels radiative rates lifetimes Al-like tungsten

Geometric proportions： The underlying structure of design process for Islamic geometric patterns

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Frontiers of Architectural Research 2012年第4期1卷 380-391页

作者： Loai m. Dabbour Department of Architectural Engineering and Building Systems Alzaytoonah University of Jordan Amman 11733 Jordan

This paper discusses geometric proportions which serve as a design toot, especially for IsLamic pattern design. The key rote of geometry in Islamic patterns is discussed with relation to proportions which act as the underlying structure of the design process. Evaluations based on spatial structure and esthetic criteria are integrated into the conceptual phase of the design process. Proportions serve two objectives; firstly, in pattern design, proportions are strongly linked to geometry, which can be viewed as a self-guiding method of esthetically proven design. SecondLy, geometric proportions regulate primarily the order of patterns; while at the same time they mediate between the two poles of order and diversity as wetl as among different esthetic revels. This paper anatyzes geometric principles and design features of traditional Istamic patterns, involving geometric proportion anatysis. It also describes the syntheses of Islamic patterns from the perspectives of Islamic cosmology, philosophy and metaphysics of geometry, which can be seen as following a pre-established principle of geometric and proportional design with high accuracy and great precision. Furthermore, the underlying relationship between cosmology and geometry is manifested in Islamic patterns where geometry acts as the vocabulary underpinning the pattern language. These findings support the argument that geometry was independently discovered and applied by Islamic culture as a universal language, constituting one of the most important multicultural symbols in design.

关键词： Geometry Proportions Islamic patterns

Smooth quadrotor trajectory generation for tracking a moving target in cluttered environments

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Science China(Information Sciences) 2021年第7期64卷 132-147页

作者： Lele XI Zhihong PENG Lei JIAO Ben m.CHEN School of Automation Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex System Peng Cheng Laboratory Department of mechanical and Automation Engineering The Chinese University of Hong Kong

In this paper, we present a trajectory generation method of a quadrotor, based on the optimal smoothing B-spline, for tracking a moving target with consideration of relative tracking pattern or limited field of view of the onboard sensor in cluttered environments. Compared to existing methods, safe flying zone,vehicle physical limits, and smoothness are fully considered to guarantee flight safety, kinodynamic feasibility, and tracking performance. To tackle the cluttered environments, a parallel particle swarm optimization algorithm is applied to find the feasible waypoints that the generated trajectory should be as close to as possible, with consideration of the target’s future state as well as obstacles to trade off the tracking performance and flight safety. Then, a sequential motion planning method, considering the above constraints, is applied and embedded into a cost function for solving the problem of robust tracking trajectory generation for the quadrotor via a convex optimization approach. The feasibility and effectiveness of the proposed method are verified by numerical simulations.

关键词： quadrotor target tracking trajectory generation B-spline convex optimization

Performance study of jute-epoxy composites/sandwiches under normal ballistic impact

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Defence Technology（防务技术） 2020年第4期16卷 947-955页

作者： Sangamesh Rajole K.S.Ravishankar S.m.Kulkarni Department of mechanical Engineering National Institute of Technology KarnatakaSurathkalMangalore 575025India Department of metallurgical and materials Engineering National Institute of Technology KarnatakaSurathkalMangalore 575025India

This study is undertaken to explore the use of natural fiber Jute-epoxy(JE),Jute-epoxy-rubber(JRE)sandwich composite for ballistic energy *** absorbed and residual velocities for these composites are evaluated analytically and through Finite Element Analysis(FEA).FE analysis of JE plates is carried out for different thicknesses(3,5,10 and 15 mm).JE plates and JRE sandwiches having the same thickness(15 mm) are fabricated and tested to measure residual velocity and energy *** analytical results are found to agree well with the results of FE analysis with a maximum error of 9%.The study on JE composite plate reveals that thickness influences the energy *** and FE analysis study showed that JRE sandwiches have better energy absorption than JE *** absorption of a JRE sandwich is about 71% greater than JE *** obtained from FEA and testing are in good agreement,SEm analysis confirms composites failed by fiber rupture and fragmentation.

关键词： Energy absorption Composites Polymer composites Ballistic impact High velocity impact

Interpretable modeling of metallurgical responses for an industrial coal column flotation circuit by XGBoost and SHAP-A “conscious-lab” development

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International Journal of mining Science and Technology 2021年第6期31卷 1135-1144页

作者： S.Chehreh Chelgani H.Nasiri m.Alidokht minerals and metallurgical Engineering Dept.of CivilEnvironmental and Natural Resources EngineeringLuleåUniversity of TechnologySE-97187 LuleåSweden Department of Computer Engineering Amirkabir University of TechnologyTehranIran Tabas Parvardeh Coal Company(TPCCO) BirjandIran

Surprisingly,no investigation has been explored relationships between operating variables and metallurgical responses of coal column flotation(CF) circuits based on industrial databases for under operation *** a novel approach,this study implemented a conscious-lab "CL" for filling this *** this approach,for developing the CL dedicated to an industrial CF circuit,SHapley Additive explanations(SHAP) and extreme gradient boosting(XGBoost) were powerful unique machine learning systems for the first time *** explainable artificial intelligence models could effectively convert the dataset to a basis that improves human capabilities for better understanding,reasoning,and planning the *** could provide precise multivariable correlation assessments between the CF dataset by using the Tabas Parvadeh coal plant(Kerman,Iran),and showed the importance of solid percentage and washing water on the metallurgical responses of the coal CF *** could predict metallurgical responses(R-square> 0.88) based on operating variables that showed quite higher accuracy than typical modeling methods(Random Forest and support vector regression).

关键词： SHAP XGBoost Explainable AI Coal flotation Separation efficiency

mitigation of the blast load effects on a building structure using newly composite structural configurations

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Defence Technology（防务技术） 2021年第1期17卷 75-84页

作者： Ahmed K.Taha m.S.Zahran Zhengguo Gao School of Transportation Science and Engineering Beihang University(Beijing University of Aeronautics and Astronautics)Beijing100191PR China Department of Civil Engineering Military Technical CollegeEgypt

In this study,a nonlinear three-dimensional hydrocode numerical simulation was carried out using AUTODYN-3D to investigate the effect of blasting of a high explosive material(TNT)against several configurations of the composite *** numerical models were carried out to study the effect of varying the thickness of the walls and the effect of adding an air layer or aluminum foam layer inside two layers of concrete in mitigating the effect of blast waves on the structure *** results showed that increasing the thickness of walls has a good effect on mitigating the effect of blast *** a layer of air was added,the effect of blast waves was exaggerated,while when a layer of aluminum foam was added the blast wave effects were mitigated with a reasonable percentage.

关键词： Concrete structures Blast waves Numerical simulation TNT

Prospects for 3D bioprinting of organoids

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Bio-Design and manufacturing 2021年第3期4卷 627-640页

作者： Preety Rawal Dinesh m.Tripathi Seeram Ramakrishna Savneet Kaur Department of molecular and Cellular medicine Institute of Liver and Biliary Sciences(ILBS)D1Vasant KunjNew Delhi 110070India School of Biotechnology Gautam Buddha UniversityGreater NoidaIndia Department of mechanical Engineering National University of SingaporeSingaporeSingapore

Three-dimensional(3D)organoids derived from pluripotent or adult tissue stem cells seem to possess excellent potential for studying development and disease mechanisms alongside having a myriad of applications in regenerative ***,lack of precise architectures and large-scale tissue sizes are some of the key limitations of current organoid technologies.3D bioprinting of organoids has recently emerged to address some of these *** this review,we discuss 3D bioprinting with respect to the use of bioinks and bioprinting methods and highlight recent studies that have shown success in bioprinting of stem cells and *** also summarize the use of several vascularization strategies for the bioprinted organoids,that are critical for a complex tissue *** fully realize the translational applications of organoids in disease modeling and regenerative medicine,these areas in 3D bioprinting need to be appropriately harnessed and channelized.

关键词： Three-dimensional bioprinting Bioink Organoid microfluidics Extracellular matrix(ECm) Biomaterial