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Tracing Escaping Structure in the Northern Indo-China Peninsula by Openness and Remote Sensing

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Journal of Earth Science 2017年第1期28卷 147-160页

作者： Jie zhang Qinglai Feng zhi Zhang State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Nanjing Center China Geological Survey School of Earth Sciences China University of GeosciencesWuhan

The Openness based on DEM emphasizes the terrain convexity and concavity. It facilitates the interpretation of detailed landforms on the Earth＇s surface. Compared with the layer stacking of ETM＋ with less three-dimensionality and visualizability and with indefinite details of linear images in the deep cutting or deep covered region, the Openness is used for accurate interpretation of tectonic geomorphic units and linear structures. In this paper, the ETM＋ images（741 RGB） and RRIM based on Openness combined with the field geological investigation are used to trace the escaping structure in SE Asia. The east boundary is Ailaoshan shear zone and the west boundary is Uttaradit-Dien Bien Phu fault, which together form the southwards extruding wedge block. The arc boundary surface of the southern Khorat Plateau is jutted to the north. The NW and NE sides of Khorat Plateau are traversed by Uttaradit-Dien Bien Phu fault and Thakhek-Da Nang fault, respectively, resulting in a blocked escaping structure. The SE margins of Truong Son structure belt and Song Ma structure belt are both arcs jutting to SE. These arc structures clamped by faults or related to the fault on one side indicating the material flow direction obviously, are the most specific manifestation of escaping structures. Moreover, these push units are extruded from south to north successively.

关键词： Openness Indo-China Peninsula escaping structure remote sensing.

Effect of relaxation time on the squeezed correlations of bosons for evolving sources in relativistic heavy-ion collisions

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Nuclear Science and Techniques 2022年第2期33卷 87-92页

作者： Wei-Ning zhang Peng-zhi Xu School of Physics Dalian University of TechnologyDalian 116024China College of Computer Science and Technology Jilin Normal UniversitySiping 136000China

The squeezed back-to-back correlation(SBBC)of a boson-antiboson pair is sensitive to the time distribution of the particle-emitting source,and the SBBC function for an evolving source is expected to be affected by the relaxation time of the system.In this study,we investigated the effect of relaxation time on the SBBC function.We propose a method for calculating the SBBC function with relaxation-time approximation for evolving sources.SBBC functions of D^(0)D^(-0)in relativistic heavy-ion collisions were investigated using a hydrodynamic model.We found that the relaxation time reduces the amplitudes of the SBBC functions.This becomes apparent for long relaxation times and large initial relative deviations of the chaotic and squeezed amplitudes from their equilibrium values in the temporal steps.

关键词： Relaxation time Squeezed back-to-back correlation Evolving source Relativistic heavy-ion collisions

Guidance and evaluation system for smooth operation of heavy-haul trains

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Transportation Safety and Environment 2020年第3期2卷 226-235页

作者： zhi Zhang Xiang Wei Tao zhang Songxu Wang Research Institute of Science and Technology of Daqin Railway Co. Ltd.Taiyuan030013China China Railway Taiyuan Bureau Group Co. Ltd.Taiyuan030013China National Railway Administration of People’s Republic of China Beijing100070China

The operation rules and methods for heavy-haul trains were studied and summarized according to the characteristics of the Daqin Railway,such as a large traffic volume,a high density and high-speed and difficult-to-operate heavy-haul trains.Combined with traction calculation and operation experience,these can be quantificationally decomposed into an evaluation standard for the smooth modularized operation of heavy-haul trains that can be recognized by computers.A train operation guidance system was designed to collect locomotive drivers’operation data,display the actual operation and standard curves in real time and give voice prompts and violation-operation alarms for safety-critical operation.In addition,software for operation analysis and evaluation was developed according to the quantified smooth operation standard.The smooth operation of heavy-haul trains was evaluated and statistically analysed through a comparative analysis of the actual operation records.Moreover,a train impact force detection device capable of monitoring the three-dimensional impact force of heavy-haul trains in real time was developed.Meanwhile,the evaluation standard for smooth operation was verified and optimized by real-time monitoring of the impact force of heavy-haul trains.Finally,on the basis of the above studies,a complete closed-loop management scheme for the smooth operation of heavy-haul trains was constructed,and the objectives of optimizing train operation strategy,standardizing drivers’operations and ensuring the smooth operation of trains were realized through application.

关键词： heavy-haul trains smooth operation traction calculation synchronous operation simplified line model

Corrosion mechanism of Mg alloys involving elongated long-period stacking ordered phase and intragranular lamellar structure

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Journal of Materials Science & Technology 2023年第20期151卷 190-203页

作者： Jinshu Xie Jinghuai zhang zhi Zhang Zijian Yu zhihao Xu Ru Wang Daqing Fang Xiaobo zhang Xiaoru zhang Ruizhi Wu Key Laboratory of Superlight Material and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing Institute of TechnologyNanjing 211167China

It is a long-term challenge to further improve the corrosion resistance while ensuring the strength of magnesium(Mg)alloys.Revealing the effect of potential fluctuation on the micro-galvanic corrosion and the subsequent film formation is important for understanding the corrosion mechanism of Mg alloys with multiple strengthening phases/structures.Here,we prepared the high-strength Mg-14.4Er-1.44Zn-0.3Zr(wt.%)alloys containing hybrid structures,i.e.,elongated long-period stacking ordered(LPSO)blocks+intragranular stacking faults(SFs)/LPSO lamellae.The Mg alloy with elongated LPSO blocks and intragranular LPSO lamellae(EZ-500 alloy)obtains good corrosion resistance(2.2 mm y^(–1)),while the Mg alloy containing elongated LPSO blocks and intragranular SFs(EZ-400 alloy)shows a significantly higher corrosion rate(6.9 mm y^(–1)).The results of scanning Kelvin probe force microscopy(SKPFM)show the elongated LPSO blocks act as cathode phase(87 mV in EZ-400 alloy),and the SFs serve as the weak anode(30 mV in EZ-400 alloy),resulting in high potential fluctuation in EZ-400 alloy.On the contrary,both elongated blocks and intragranular lamellae are cathodic LPSO phase(67–69 mV)in EZ-500 alloy,leading to a lower potential fluctuation.Quasi in-situ atomic force microscope(AFM)observation indicates that high potential fluctuation would cause strong micro-galvanic corrosion,and subsequently leads to the failure in rapid formation of corrosion film,finally forming a loose and porous film,while relatively low potential fluctuation could result in more uniform corrosion mode and facilitate the rapid formation of protective film.Therefore,we propose that it is an effective way to develop high-strength corrosionresistant Mg alloys by controlling the potential fluctuation to form a“uniform potential”strengthening microstructure。

关键词： Mg alloys Stacking faults LPSO phase SKPFM Quasi in-situ AFM Corrosion behavior Potential fluctuation

大规模天线多入多出认知无线网络中的多用户传输速率和能量分析（英文）

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Frontiers of Information Technology & Electronic Engineering 2018年第5期19卷 674-684页

作者： Shang LIU Ishtiaq AHMAD Ping zhang zhi Zhang State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Department of Electrical Engineering University of Lahore

讨论了在包含中继和大规模多入多出天线下的认知无线网络传输性能和能量分配问题。首先得到了在不考虑认知情况下的中继辅助大规模天线网络的下行传输性能,运用功率分配准则,第k个用户的渐近信干噪比与快衰落无关,当基站天线数和中继天... 详细信息

讨论了在包含中继和大规模多入多出天线下的认知无线网络传输性能和能量分配问题。首先得到了在不考虑认知情况下的中继辅助大规模天线网络的下行传输性能,运用功率分配准则,第k个用户的渐近信干噪比与快衰落无关,当基站天线数和中继天线数的比值趋于无穷大时,整个传输过程的传输性能只与从中继到用户侧的传输有关,而与另外一侧的传输无关。接着给出了在完美和非完美信道情况下的认知大规模多入多出天线中继网络性能的闭式表达式。当主用户基站、次级用户基站、中继基站的天线数目趋于无穷大时,传输性能与快衰落无关,主、次网络之间的干扰能被完全消除,次级网络传输性能与干扰温度无关,次级网络可用峰值功率进行传输而不对主用户网络产生干扰。定义了主用户网络的效用函数,通过凸优化分析得到最佳中继发射功率。系统仿真验证了该结论。通过仿真,得到了系统传输速率与天线数目、中继功率、天线数目比值的关系。在多用户认知无线网络中,运用大规模多入多出天线的线性预编码方式能够极大减少干扰,提高传输效率,主用户网络和次级用户网络可以独立传输。

关键词：多用户收音机多输入网络产量 MIMO SINR 用户系统

Sn-Bi bimetallic interface induced by nano-crumples for CO_(2) electroreduction to formate

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Rare Metals 2022年第12期41卷 3943-3945页

作者： Li Li zhi-Cheng zhang Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China

Electrochemical carbon dioxide(CO_(2))reduction reaction(CO_(2)RR),powered by a renewable energy source,to valueadded chemicals and fuels is a promising solution to mitigate the ever-increasing CO_(2)emission and buil... 详细信息

关键词： dioxide carbon Electrochemical

Gain and phase errors active calibration method based on neural network for arrays with arbitrary geometry

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The Journal of China Universities of Posts and Telecommunications 2023年第2期30卷 8-17页

作者： Han Ziwen zhang zhi Guo Yu State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

The manifold matrix of the received signals can be destroyed when the array is with the gain and phase errors,which will affect the performance of the traditional direction of arrival(DOA)estimation approaches.In this paper,a novel active array calibration method for the gain and phase errors based on a cascaded neural network(GPECNN)was proposed.The cascaded neural network contains two parts:signal-to-noise ratio(SNR)classification network and two sets of error estimation subnetworks.Error calibration subnetworks are activated according to the output of the SNR classification network,each of which consists of a gain error estimation network(GEEN)and a phase error estimation network(PEEN),respectively.The disadvantage of neural network topology architecture is changing when the number of array elements varies is addressed by the proposed group calibration strategy.Moreover,due to the data characteristics of the input vector,the cascaded neural network can be applied to arrays with arbitrary geometry without repetitive training.Simulation results demonstrate that the GPECNN not only achieves a better balance between calibration performance and calibration complexity than other methods but also can be applied to arrays with different numbers of sensors or different shapes without repetitive training.

关键词： active array calibration cascaded neural network direction of arrival(DOA)estimation

Prey life stages modulate effects of predation stress on prey lifespan,development,and reproduction in mites

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Insect Science 2023年第3期30卷 844-856页

作者： Xiaoying Weil Guangyun Li zhi-Qiang zhang School of Biological Sciences The University of AucklandAucklandNew Zealand Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionSouthwest UniversityChongqingChina Manaaki Whenua-Landcare Research AucklandNewZealand

The non-consumptive effects of predator-induced stress can influence a variety of life-history traits.Many previous studies focused only on short-term effects such as development and reproductive rates.Recent studies have showed that long-term predation stress(given during the whole life of the prey)and short-term predation stress(provided during the immature stage of the prey)could generate completely opposite results:the former could decrease lifespan,whereas the later could increase lifespan.However,it is still unclear whether the advantage is because of the short duration of exposure or the early stage of life during which exposure was exerted.Thus,in this study,the prey(Tyrophagus putrescentiae)was exposed to predation stress from the predator(Neoseiulus cucumeris)during different life stages(larva,protonymph,tritonymph,first 5 d of oviposition,the full lifespan or none of the above).The results showed that the predation stress supplied during larval and protonymphal stage delayed development,reduced fecundity and prolonged lifespan of the prey,while the stress given during tritonymphal stage only reduced lifespan slightly and the stress given during the first 5 d of oviposition did not change lifespan but reduced fecundity.This study indicated that the effects of predation stress are dependent on prey life stage and the predation stress experienced in the early life stages is important to lifespan modulation.

关键词： early life experience lifespan non-consumptive effects predation stress tyrophagus

A universal probe for simultaneous detection of six pospiviroids and natural infection of potato spindle tuber viroid(PSTVd) in tomato in China

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Journal of Integrative Agriculture 2023年第3期22卷 790-798页

作者： zhang Yu-hong LI zhi-xin DU Ya-jie LI Shi-fang zhang zhi-xiang State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China Keshan Branch of Heilongjiang Academy of Agricultural Sciences Qiqihar 161005P.R.China College of Agronomy and Biotechnology Hebei Normal University of Science&TechnologyQinhuangdao 066004P.R.China

Several viroids in the genus Pospiviroid can infect tomato(Solanum lycopersicum)and cause severe diseases,posing a serious threat to tomato production.For simultaneous detection of six tomato-infecting pospiviroids-columnea latent viroid(CLVd),pepper chat fruit viroid(PCFVd),potato spindle tuber viroid(PSTVd),tomato apical stunt viroid(TASVd),tomato chlorotic dwarf viroid(TCDVd),and tomato planta macho viroid(TPMVd),we developed a universal probe based on a highly conserved 61 nt long sequence shared among them.Compared with their specific probes,the universal probe has a similar,though slightly reduced,detection sensitivity and has the advantages of simple and cost-effective preparation and simultaneous detection of the six pospiviroids.In addition,the universal probe was used in dot-blot hybridization assays for a large-scale survey of viroid(s)in tomato plantings in China.Only PSTVd was detected in a few greenhouse-planted tomato plants.Sequence analysis revealed that these tomato PSTVd isolates may have been introduced from tomato seeds imported from abroad.

关键词： tomato viroid simultaneous detection molecular hybridization pospiviroids