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Types and biotic successions of Ordovician reefs in China

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Chinese Science Bulletin 2012年第10期57卷 1160-1168页

作者： WANG JianPo DENG XiaoJie WANG guan LI yue Wuhan Center of Geological Survey Wuhan 430205 China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

Ordovician reefs are located in the South China,Tarim,and North China blocks,in low-latitude epicontinental marine regions and mostly consist of large-scale carbonate *** the Paleozoic,faunal radiation reef biota diverged and thrived in diverse paleogeographic *** reefs of the Early Ordovician,Calathium-lithistid sponge-algal reefs of the late Early Ordovician to early Middle Ordovician,and coral-stromatoporoid-algal reefs of the early Late Ordovician,indicate change from Cambrian to Paleozoic ***-stromatoporoid-algal reefs were the basic communities after 100 *** macroevolution of biotic struc-tures generally shows increased complexity;the evolution of China's reef biota parallels that *** aspects are:(1) The Calathium-algal reefs from the early Tremadocian Nantzinkuan Formation,Zhangjiajie,western Hunan are the pioneer reefs,and the Darriwillian Yijianfang Formation,Bachu are the relic reefs.(2) The bryozoan-dominated reefs of the late Tremadocian Fenhsiang Formation,Middle Yangtze Platform are unique.(3) The early coral-stromatoporoid-algal reefs are highly restricted in China.(4) The algal reefs from the latest Katian on the western margin of the Yangtze Platform,represent an abnormal reef-building environment during the initial stages of Gondwanan glaciations.

关键词：生物演替生物礁中国奥陶系古地理环境类型碳酸盐岩台地早奥陶世

A novel feature extraction method for ship-radiated noise

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Defence Technology（防务技术） 2022年第4期18卷 604-617页

作者： Hong Yang Lu-lu Li Guo-hui Li Qian-ru guan School of Electronic Engineering Xi’an University of Posts and TelecommunicationsXi’anShaanxi710121China

To improve the feature extraction of ship-radiated noise in a complex ocean environment,a novel feature extraction method for ship-radiated noise based on complete ensemble empirical mode decomposition with adaptive selective noise(CEEMDASN) and refined composite multiscale fluctuation-based dispersion entropy(RCMFDE) is *** is proposed in this paper which takes into account the high frequency intermittent components when decomposing the *** addition,RCMFDE is also proposed in this paper which refines the preprocessing process of the original signal based on composite multi-scale ***,the original signal is decomposed into several intrinsic mode functions(IMFs)by *** distribution ratio(EDR) and average energy distribution ratio(AEDR) of all IMF components are ***,the IMF with the minimum difference between EDR and AEDR(MEDR)is selected as characteristic *** RCMFDE of characteristic IMF is estimated as the feature vectors of ship-radiated ***,these feature vectors are sent to self-organizing map(SOM) for classifying and *** proposed method is applied to the feature extraction of ship-radiated *** result shows its effectiveness and universality.

关键词： Complete ensemble empirical mode decomposition with adaptive noise Ship-radiated noise Feature extraction Classification and recognition

Critical scale grain size for optimal lifetime of TBCs

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Journal of Materials Science & Technology 2022年第20期115卷 241-250页

作者： Lin Chen Guo-hui Meng Chang-Jiu Li guan-Jun Yang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China

Thermal barrier coatings(TBCs)suffer from spalling failure resulting from the rapid growth of thermally grown oxides(TGO)on the metallic bond *** this study,to achieve the optimal lifetime of TBCs,a lifetime phase diagram was constructed for the entire service of ***,both the thermal mismatch stress during thermal cycling and the TGO growth stress during thermal exposure were ***,thickening behavior of the Al_(2)O_(3) scale related to grain size was ***,transverse delamination failure due to the thermal mismatch stress was ***,vertical cracking failure related to early scale growth was ***,a critical scale grain size of~2.5μm was identified for achieving the optimal lifetime of *** was experimentally proved that vertical cracking of the Al_(2)O_(3) scale occurred during early oxidation as the scale grain size was larger than~4μm after *** proposed lifetime phase diagram and critical scale grain size effect serve as novel criteria for the design of next-generation durable TBCs.

关键词： TGO growth Grain size Grain boundaries Channel cracking Service lifetime

Study on Mechanism of Gold Leaching by Thiourea in the Presence of Sodium Sulphite

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Journal of Central South University 2000年第3期12卷 113-116页

作者： HU yue-hua GUO guang-fa QIU guan-zhou Department of Mineral Engineering Central South UniversityChangsha 410083China

The linear potential sweep voltammetry and electrochemical methods were used to study the mechanism and kinetics of gold dissolution in thiourea solution in the absence and presence of sodium *** results show that in the absence of sodium sulfite the dissolution rate of gold in thiourea solution is relatively slow and it increases with the increase of the concentration of thiourea and decreases with pH. Thiourea is easily oxidized to formamidine disulphide, which reduces the leaching efficiency and increases reagent consumption. In the presence of sodium sulphite, the effective concentration of thiourea is increased and the dissolution rate of gold in thiourea solution is greatly increased. The activation energy required for gold dissolution in thiourea solution with sodium sulphite is 20.9 kJ·mol -1 which is much lower than 55.0 kJ·mol -1 in the absence of sodium sulphite. It is evident that sodium sulphite has a significant effect on the electrochemical reaction kinetics of gold in thiourea solution.

关键词： gold leaching thiourea sodium sulphite mechanism

Supporting multi-user real-time VBR video service using dynamic bandwidth management based on prediction

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 64-71页

作者： XU Zhi-yuan LI hui LU yue-ming JI yue-feng Key Laboratory of Optical Communications and Lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

Real-time variable bit rate（VBR） video is expected to take a significant portion of multimedia ***,plentiful challenges to VBR video service provision have been raised for its characteristic of high traffic *** support multi-user real-time VBR video transmission with high bandwidth utilization and satisfied quality of service（QoS）,this article proposes a practical dynamic bandwidth management *** scheme forecasts future media rate of VBR video by employing time-domain adaptive linear predictor and using media delivery index（MDI） as both QoS measurement and complementary management *** addition,to support multi-user application,an adjustment priorities classified strategy is also put ***,a test-bed based on this management scheme is *** experimental results demonstrate that the scheme proposed in this article is efficient with bandwidth utilization increased by 20%-60% compared to a fixed service rate and QoS guaranteed.

关键词： dynamic bandwidth management MDI QoS real-time time-domain adaptive linear predictor VBR video

Effects of the planarity and heterogeneity of networks on evolutionary two-player games

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Chinese Physics B 2018年第12期27卷 164-171页

作者： Xu-Sheng Liu Zhi-Xi Wu Jian-yue guan Institute of Computational Physics and Complex Systems Lanzhou University

We study the effects of the planarity and heterogeneity of networks on evolutionary two-player symmetric games by considering four different kinds of networks, including two types of heterogeneous networks: the weighted planar stochastic lattice(a planar scale-free network) and the random uncorrelated scale-free network with the same degree distribution as the weighted planar stochastic lattice; and two types of homogeneous networks: the hexagonal lattice and the random regular network with the same degree k_0= 6 as the hexagonal lattice. Using extensive computer simulations, we found that both the planarity and heterogeneity of the network have a significant influence on the evolution of cooperation, either promotion or inhibition, depending not only on the specific kind of game(the Harmony, Snowdrift, Stag Hunt or Prisoner's Dilemma games), but also on the update rule(the Fermi, replicator or unconditional imitation rules).

关键词： evolutionary two-player games planarity heterogeneity

Effect of flame conditions on abrasive wear performance of HVOF sprayed nanostructured WC-12Co coatings

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 72-76页

作者： WANG Yu-yue LI Chang-jiu MA Jian YANG guan-jun State Key Laboratory for Mechanical Behavior of Materials Xi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of MaterialsXi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of MaterialsXi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of MaterialsXi''an Jiaotong University Xi''an 710049 China

Nanostructured WC-12Co coatings were deposited by high velocity oxy-fuel (HVOF) spraying with an agglomerated powder. The effect of flame conditions on the microstructure of the nanostructured coatings was investigated. The wear properties of the coatings were characterized using a dry rubber-wheel wear test. The results show that the nanostructured WC-Co coatings consist of WC, W2C, W and an amorphous binder phase. The microstructure of the coating is significantly influenced by the ratio of oxygen flow to fuel flow. Under the lower ratio of oxygen/fuel flow, the nanostructured coating presents a relative dense microstructure and severe decarburization of WC phase occurs during spraying. With increasing ratio of oxygen/fuel flow, the bonding of WC particles in the coating becomes loose resulting from the original structure of feedstock and the decarburization of WC becomes less owing to limited heating to the powder. Both the decarburization of WC particles in spraying and the bonding among WC particles in the coatings affect the wear performance. The examination of the worn surfaces of the nanostructured coatings reveals that the dominant wear mechanisms would be spalling from the interface of WCCo splats when spray particles undergo a limited melting. While the melting state of the spray particles is improved,the dominant wear mechanisms become the plastic deformation and plowing of the matrix and spalling of WC particles from the matrix.

关键词： high velocity oxy-fuel spraying nanostructure abrasive wear performance WC-Co coating

Flexible scheduling ensuring inter-ONU-group fairness in 1G/10G EPON coexistence system

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 16-22页

作者： LI Qi LI hui JI yue-feng Key Laboratory of Optical Communications and Lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

In recent years, 10 Gbit/s Ethemet passive optical networks （10G EPON） have been gaining considerable interests because of its high bandwidth capability. To ensure smooth transition from 1 Gbit/s to 10 Gbit/s equipment and to avoid a significant one-time investment into such a cost-sensitive market, coexistence of gigabit Ethernet passive optical networks （GEPON） and 10G EPON system are necessary. In this article, coexistence system architecture and a novel bandwidth allocation algorithm called weight-optimized dynamic bandwidth allocation for coexistence EPON （WOCE-DBA） for the system is proposed. The simulation results show that this algorithm can guarantee fair bandwidth sharing among different optical network unit （ONU） groups, without ignoring the inter-ONU and intra-ONU fairness. Most importantly, it can flexibly adapt to the system composition variations and save efforts needed to modify the bandwidth scheduling mechanism during the migration process from GEPON to 10G EPON.

关键词： 10G EPON coexistence system dynamic bandwidth allocation (DBA) intra-ONU-group fairness simulation and modeling

Non-monotonic behavior of jam probability and stretchedexponential distribution in pedestrian counterflow

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Chinese Physics B 2024年第9期33卷 259-266页

作者： Ze-Hao Chen Zhi-Xi Wu Jian-yue guan College of Physical Science and Technology Guangxi Normal UniversityGuilin 541004China Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Provinceand Key Laboratory for Quantum Theory and Applications of the Ministry of EducationLanzhou UniversityLanzhou 730000China

We adopt a floor field cellular automata model to study the statistical properties of bidirectional pedestrian flow movingin a straight corridor. We introduce a game-theoretic framework to deal with the conflict of multiple pedestrians tryingto move to the same target location. By means of computer simulations, we show that the complementary cumulative distributionof the time interval between two consecutive pedestrians leaving the corridor can be fitted by a stretched exponentialdistribution, and surprisingly, the statistical properties of the two types of pedestrian flows are affected differently by theflow ratio, i.e., the ratio of the pedestrians walking toward different directions. We also find that the jam probability exhibitsa non-monotonic behavior with the flow ratio, where the worst performance arises at an intermediate flow ratio of around0.2. Our simulation results are consistent with some empirical observations, which suggest that the peculiar characteristicsof the pedestrians may attributed to the anticipation mechanism of collision avoidance.

关键词： traffic and crowd dynamics evolutionary game theory