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Pythagorean Uncertain Linguistic Variable Hamy Mean Operator and Its Application to Multi-attribute group Decision Making

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IEEE/CAA Journal of Automatica Sinica 2019年第2期6卷 527-539页

作者： Huidong Wang Shifan He Chengdong Li Xiaohong Pan IEEE the School of Management Science and Engineering Shandong University of Finance and Economics the School of Information and Electrical Engineering Shandong Jianzhu University

Pythagorean fuzzy set(PFS) can provide more flexibility than intuitionistic fuzzy set(IFS) for handling uncertain information, and PFS has been increasingly used in multi-attribute decision making problems. This paper proposes a new multiattribute group decision making method based on Pythagorean uncertain linguistic variable Hamy mean(PULVHM) operator and VIKOR method. Firstly, we define operation rules and a new aggregation operator of Pythagorean uncertain linguistic variable(PULV) and explore some properties of the ***, taking the decision makers' hesitation degree into account, a new score function is defined, and we further develop a new group decision making approach integrated with VIKOR method. Finally, an investment example is demonstrated to elaborate the validity of the proposed method. Sensibility analysis and comprehensive comparisons with another two methods are performed to show the stability and advantage of our method.

关键词： Hamy mean(HM) operator multi-attribute group decision making(MAGDM) Pythagorean fuzzy set Pythagorean uncertain linguistic variable

Mechanical mechanism of overlying strata breaking and development of fractured zone during close-distance coal seam group mining

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International Journal of Mining Science and Technology 2020年第2期30卷 207-215页

作者： Jianguo Ning Jun Wang Yunliang Tan Qiang Xu College of Mining and Safety Engineering State Key Laboratory Breeding Base for Mining Disaster Prevention and ControlShandong University of Science and TechnologyQingdao 266590China

This study mainly investigates the mechanical mechanism of overlying strata breaking and the development of fractured zones during close-distance coal seam group mining in the Gaojialiang coal ***,a mechanical model for the second"activation"of broken overlying strata is established,and the related mechanical"activation"conditions are obtained.A recursive formula for calculating the separation distance of overlying strata is ***,a height determining method for predicting the height of fractured zones during close-distance coal seam group mining is proposed based on two values,namely,the separation distance and ultimate subsidence value of overlying *** method is applied to calculate the fractured zone heights in nos.20107 and 20307 mining *** calculated results are almost equal to the field observation ***,a modified formula for calculating the height of a waterflowing fractured zone is proposed.A comparison of the calculated and observed results shows that the errors are *** height determining method and modified formula not only build a theoretical foundation for water conservation mining at the Gaojialiang coal mine,but also provide a reference for estimating the height of water-flowing fractured zones in other coal mines with similar conditions.

关键词： Coal seam group Activation mechanism Separation Water-flowing fractured zone Modified formula

Adsorption kinetics of platinum group elements onto macromolecular organic matter in seawater

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Acta Oceanologica Sinica 2019年第8期38卷 8-16页

作者： Kai Liu Xuelu Gao Qianguo Xing Fushan Chen CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Yantai 264003 China University of Chinese Academy of Sciences Beijing 100049 China Dongying Municipal Bureau of Marine Development and Fisheries Dongying 257000 China College of Marine Sciences and Bioengineering Qingdao University of Science and Technology Qingdao 266042 China

Adsorption kinetics of the interaction between Pt, Pd and Rh(defined here as platinum group elements, PGEs)ions and macromolecular organic compounds(MOCs,>10 kDa), including humic acid, carrageenan and bovine serum albumin, and different cutoff fractions of natural organic matter(>1 kDa and >3 kDa) obtained from seawater using centrifugal ultrafiltration devices were investigated. For a given element, all the adsorption kinetics did not reach equilibrium except the interaction between Pt and >1 kDa cutoff, and between Pd and humic *** all the tested MOCs, the adsorption kinetics could be divided into two stages, a rapid adsorption process in the first 8 h and the desorption stage after the first 8 h until the equilibrium. The change trend of partition coefficient(log10Kd) values with experiment time was consistent with that of the kinetic curves. However, in the interaction between PGE ions and natural dissolved organic matter(NDOM), an obvious difference in the change trends of log10Kd and kinetic curves was observed. It indicated that the partition behavior of PGE ions interacting with NDOM in seawater was a combined effect of different organic constituents. The adsorption and log10Kd of PGEs in the >1 kDa NDOM fraction were higher and more stable than those in the >3 kDa NDOM fraction. The results also indicated that the 1–3 kDa NDOM may dominate the interaction between PGEs ions and NDOM. Moreover, no kinetic model could perfectly simulate the adsorption process. It indicated that the colloidal struction and morphology of MOCs or NDOM in seawater might be inhomogeneous. Hence, the interaction between PGE ions and organic matter in seawater was a complicated process and needs further research.

关键词： adsorption kinetics platinum group elements macromolecular organic compounds natural organic matter seawater

The Langjiexue group is an in situ sedimentary sequence rather than an exotic block: Constraints from coeval Upper Triassic strata of the Tethys Himalaya(Qulonggongba Formation)

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Science China Earth Sciences 2019年第5期62卷 783-797页

作者： Zhongyu MENG Jiangang WANG Weiqiang JI Hao ZHANG Fuyuan WU Eduardo GARZANTI Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences Laboratory for Provenance Studies Department of Earth and Environmental Sciences Università di Milano-Bicocca

The Upper Triassic Langjiexue group in southeastern Tibet has long been an enigmatic geological unit. It belongs tectonically to the northern Tethys Himalayan zone, but provenance signatures of the detritus it contains are significantly different from those of typical Tethys Himalayan sandstones. Because the Langjiexue group is everywhere in fault contact with Tethys Himalayan strata, its original paleogeographic position has remained controversial for a long time. According to some researchers, the Langjiexue group was deposited onto the northern edge of the Indian passive continental margin, whereas others interpreted it as an independent block accreted to the northern Indian margin only during final India-Asia convergence and collision in the Paleocene. This study compares the Langjiexue group and coeval Upper Triassic strata of the southern Tethys Himalayan zone(Qulonggongba Formation). Our new provenance data indicate that Qulonggongba Formation sandstones contain common felsic volcanic rock fragments, minor plagioclase, and euhedral to subhedral zircon grains yielding Late Paleozoic to Triassic ages. These provenance features compare well with those of the Langjiexue group. Because the Qulonggongba Formation certainly belongs to the Tethys Himalayan zone, the provenance similarity with the Langjiexue group indicates that the latter is also an in situ Tethys Himalayan sedimentary sequence rather than part of an exotic block. Volcanic detritus including Late Paleozoic to Triassic zircon grains in both Langjiexue group and Qulonggongba Formation are interpreted to have been derived from the distant Gondwanide orogen generated by Pan-Pacific subduction beneath the southeastern margin of Gondwana. The Qulonggongba Formation, deposited above marlstones of the lower Upper Triassic Tulong group, is overlain by India-derived coastal quartzose sandstones of the uppermost Triassic Derirong Formation. Deposition of both the Qulonggongba Formation and the Langjiexue group

关键词： Tethys Himalaya Provenance analysis Langjiexue group Detrital-zircon geochronology Tectonic setting Late Triassic Paleogeography

Microfossils from the siltstones and muddy slates:Constraint on the age of the Taowan group in the Northern Qinling Orogenic Belt,Central China

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Science China Earth Sciences 2008年第2期51卷 172-180页

作者： WANG ZongQi GAO LianDa WANG Tao JIANG ChunFa Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

The age of the Taowan group is still a hot topic in the Northern Qinling Orogenic Belt, because of limited fossil evidence from these strata and different ideals on the Cambrian fossils of the conglomerate beds and limestone blocks. Early Ordovician acritarchs, chitinozoa and scolecodonts occur in the siltstone and muddy slate beds of the Guoling, Sanchakou, Fengmaimiao and Goushenmiao Formations of the Taowan group, indicating the age of the Taowan group should be the Ordovician. These fossil assemblages consist of 7 genera and 13 species of acritarchs, 7 genera and 9 species of chitinozoa, and 2 genera and 2 species of scolecodonts.

关键词： Taowan group microfossil Early Ordovician Northern Qinling Orogenic Belt

Development of a 1200 fine group nuclear data library for advanced nuclear systems

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Nuclear Science and Techniques 2017年第5期28卷 48-52页

作者： Jun Zou Lei-Ming Shang Fang Wang Li-Juan Hao Key Laboratory of Neutronics and Radiation Safety Institute of Nuclear Energy Safety Technology Chinese Academy of Sciences Hefei 230031 China

Accurate and reliable nuclear data libraries are essential for calculation and design of advanced nuclea systems. A 1200 fine group nuclear data library Hybrid Evaluated Nuclear Data Library/Fine group(HENDL/FG with neutrons of up to 150 Me V has been developed to improve the accuracy of neutronics calculations and anal ysis. Corrections of Doppler, resonance self-shielding, and thermal upscatter effects were done for HENDL/FG Shielding and critical safety benchmarks were performed to test the accuracy and reliability of the library. The dis crepancy between calculated and measured nuclea parameters fell into a reasonable range.

关键词： Advanced nuclear system Fine group nuclear data library Effective multiplication factor

group ACTIONS ON VON NEUMANN REGULAR RINGS

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Chinese Annals of Mathematics,Series B 1994年第2期15卷 235-240页

作者： ZHANG YINHUO(Institute of Mathematics,Fudan University, Shanghai 200433, China) 复旦大学数学所上海 200433

Let A be a ring with indentity, G a finite group of automorphisms of A. The main result of this paper is that A/AG is Galois if and only if it is Frobenius and the module AGA (or AAG)is faithful. Moreover if |G| is in... 详细信息

关键词： Von Neumann regular ring Extension group Automorphism.

Definition of Very Long Baseline Interferometry (VLBI) group Delay and Relativistic Correction Model With Picosecond Precision

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Science China Mathematics 1993年第8期36卷 991-997页

作者：杨志根 Shanghai Observatory Academia Sinica Shanghai 200030 PRC

In this paper, the incorrect definition of VLBI coordinate time delay in solar system barycenter frame (B-frame) is clarified, thus correcting the error of sign of the individual term in VLBI relativistic time delay model of transformation published earlier. It is proved that the terms, i. e. the tropospheric refraction delay, the axis offset refraction delay, and the gravitational delay caused by the major planets which are respectively multiplied by the velocity and the acceleration vector of the geocenter, should be taken into account in the model mentioned above under the precision of 1 ps. Finally, the VLBI relativistic time delay model with precision of better than 1 ps is obtained.

关键词： VLBI group time delay relativistie time delay model.

New U-Pb age constraints on the upper Banxi group and synchrony of the Sturtian glaciation in South China

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Geoscience Frontiers 2017年第5期8卷 1161-1173页

作者： Gaoyuan Song Xinqiang Wang Xiaoying Shi Ganqing Jiang School of Earth Science and Resources China University of Geosciences (Beijing) Beijing 100083 China State Key Laboratory of Biogeology and Environmental Geology Beijing 100083 China Department of Geoscience University of Nevada Las Vegas NV 89154-4010 USA

The Nanhua basin in South China hosts well-preserved middle-late Neoproterozoic sedimentary and volcanic rocks that are critical for studying the basin evolution, the breakup of the supercontinent Rodinia, the nature and dynamics of the "snowball" Earth and diversification of metazoans. Establishing a stratigraphic framework is crucial for better understanding the interactions between tectonic, paleoclimatic and biotic events recorded in the Nanhua basin, but existing stratigraphic correlations remain debated, particularly for pre-Ediacaran strata. Here we report new Laser Ablation Inductively Coupled Plasma Mass Spectrometry(LA-ICPMS) U-Pb zircon ages from the middle and topmost Wuqiangxi Formation(the upper stratigraphic unit of the Banxi group) in Siduping, Hunan Province, South China. Two samples show similar age distribution, with two major peaks at ca. 820 Ma and 780 Ma and one minor peak at ca. 910 Ma, suggesting that the Wuqiangxi sandstone was mainly sourced from Neoproterozoic rocks. Two major age peaks correspond to two phases of magmatic events associated with the rifting of the Nanhua basin, and the minor peak at ca. 910 Ma may correspond to the Shuangxiwu volcanic arc magmatism, which represents pre-collision/amalgamation subduction on the southeastern margin of the Yangtze Block. The youngest zircon group from the topmost Wuqiangxi Formation has a weighted mean age of 714.6±5.2 Ma, which is likely close to the depositional age of the uppermost Banxi group. This age, along with the ages reported from other sections, constrains that the Banxi group was deposited between ca. 820 Ma and ca. 715 Ma. The age of 714.6±5.2 Ma from the top of the Wuqiangxi Formation is indistinguishable with the SIMS U-Pb age of 715.9± 2.8 Ma from the upper Gongdong Formation in the Sibao village section of northern Guangxi, South China. It is also, within uncertainties, overlapped with two TIMS U-Pb ages from pre-Sturtian strata in Oman and Canada. These ages indicate that th

关键词： Nanhua basin Wuqiangxi Formation Banxi group U-Pb zircon ages Sturtian glaciation South China