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Spatio-temporal evolution analysis of landscape pattern and habitat quality in the Qinghai Province section of the Yellow River Basin from 2000 to 2022 based on InVEST model

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Journal of Arid Land 2024年第9期16卷 1183-1196页

作者： ZHENG Guoqiang Li Cunxiu LI Runjie LUO Jing FAN Chunxia ZHU Hailing College of Geography Qinghai Normal UniversityXining 810008China Qinghai Engineering consulting Center Co. Ltd.Xining 810001China Qinghai University Xining 810016China

Habitat quality is an important indicator for evaluating the quality of *** Qinghai Province section of the Yellow River Basin plays an important role in the ecological protection of the upper reaches of the Yellow River *** comprehensively analysis the alterations of habitat quality in the Qinghai Province section of the Yellow River Basin,this study utilized the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model to calculate the habitat quality index and analyze the spatio-temporal variation characteristics of habitat quality in the study area from 2000 to 2022,and calculated seven landscape pattern indices(number of patches,patch density,largest patch index(LPI),landscape shape index(LSI),contagion index(CONTAG),Shannon diversity index,and Shannon evenness index)to research the variation of landscape pattern in the study *** results showed that the number of patches,patch density,LPI,LSI,Shannon diversity index,and Shannon evenness index increased from 2000 to 2022,while the CONTAG decreased,indicating that the landscape pattern in the Qinghai Province section of the Yellow River Basin changed in the direction of distribution fragmentation,shape complexity,and *** average value of the habitat quality index in the Qinghai Province section of the Yellow River Basin from 2000 to 2022 was *** on the value of habitat quality index,we divided the level of habitat quality into five categories:lower(0.00-0.20),low(0.20-0.40),moderate(0.40-0.60),high(0.60-0.80),and higher(0.80-1.00).Most areas were at the higher habitat quality *** lower habitat quality patches were mainly distributed in Longyang Gorge and Yellow River-Huangshui River *** 2000 to 2022,the habitat quality in most areas was stable;the increase areas were mainly distributed in Guinan County,while the decrease areas were mainly distributed in Xining City,Maqen County,Xinghai County,Qumarleb County,and Darlag *** show the extent of

关键词： InVEST model landscape pattern index habitat quality largest patch index landscape shape index Shannon evenness index

Distributed Resource Allocation in Dispersed Computing Environment Based on UAV Track Inspection in Urban Rail Transit

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Computers, Materials & Continua 2024年第7期80卷 643-660页

作者： Tong Gan Shuo Dong Shiyou Wang Jiaxin Li Division of consulting Beijing Metro Consultancy Corporation Ltd.Beijing100037China Department of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China

With the rapid development of urban rail transit,the existing track detection has some problems such as low efficiency and insufficient detection coverage,so an intelligent and automatic track detectionmethod based onUAV is urgently needed to avoid major safety *** the same time,the geographical distribution of IoT devices results in the inefficient use of the significant computing potential held by a large number of *** a result,the Dispersed Computing(DCOMP)architecture enables collaborative computing between devices in the Internet of Everything(IoE),promotes low-latency and efficient cross-wide applications,and meets users’growing needs for computing performance and service *** paper focuses on examining the resource allocation challenge within a dispersed computing environment that utilizes UAV inspection ***,the system takes into account both resource constraints and computational constraints and transforms the optimization problem into an energy minimization problem with computational *** Markov Decision Process(MDP)model is employed to capture the connection between the dispersed computing resource allocation strategy and the system ***,a method based on Double Deep Q-Network(DDQN)is introduced to derive the optimal ***,an experience replay mechanism is implemented to tackle the issue of increasing *** experimental simulations validate the efficacy of the method across various scenarios.

关键词： UAV track inspection dispersed computing resource allocation deep reinforcement learning Markov decision process

Blast waveform tailoring using controlled venting in blast simulators and shock tubes

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Defence Technology（防务技术） 2024年第7期37卷 14-26页

作者： Edward Chern Jinn Gan Alex Remennikov David Ritzel Faculty of Engineering and Information Sciences University of WollongongWollongongNSW2522Australia Dyn-FX consulting Ltd 19 Laird Ave NorthAmherstburgONN9V 2T5Canada

A critical challenge of any blast simulation facility is in producing the widest possible pressure-impulse range for matching against equivalent high-explosive *** tubes and blast simulators are often constrained with the lack of effective ways to control blast wave profiles and as a result have a limited performance *** wave shaping techniques employed in some facilities are reviewed but often necessitate extensive geometric modifications,inadvertently cause flow anomalies,and/or are only applicable under very specific *** paper investigates controlled venting as an expedient way for waveforms to be tuned without requiring extensive modifications to the driver or existing geometry and could be widely applied by existing and future blast simulation and shock tube *** use of controlled venting is demonstrated experimentally using the Advanced Blast Simulator(shock tube)at the Australian National Facility of Physical Blast Simulation and via numerical flow simulations with Computational Fluid *** venting is determined as an effective method for mitigating the impact of re-reflected waves within the blast *** control method also allows for the adjustment of parameters such as tuning the peak overpressure,the positive phase duration,and modifying the magnitude of the negative phase and the secondary shock of the blast *** paper is concluded with an illustration of the potential expanded performance range of the Australian blast simulation facility when controlled venting for blast waveform tailoring as presented in this paper is applied.

关键词： Advanced blast simulator Shock wave propagation Far-field explosion Blast loads Blast waves Computational fluid dynamics

Dynamic analysis of major public health emergency transmission considering the dual-layer coupling of community–resident complex networks

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Chinese Physics B 2024年第7期33卷 158-169页

作者：杨鹏范如国王奕博张应青 School of Economics and Management Wuhan UniversityWuhan 430072China Postdoctoral Research Station China International Engineering Consulting CorporationBeijing 100000China School of Business Administration Guizhou University of Finance and EconomicsGuiyang 550025China

We construct a dual-layer coupled complex network of communities and residents to represent the interconnected risk transmission network between communities and the disease transmission network among residents. It characterizes the process of infectious disease transmission among residents between communities through the SE2IHR model considering two types of infectors. By depicting a more fine-grained social structure and combining further simulation experiments, the study validates the crucial role of various prevention and control measures implemented by communities as primary executors in controlling the epidemic. Research shows that the geographical boundaries of communities and the social interaction patterns of residents have a significant impact on the spread of the epidemic, where early detection, isolation and treatment strategies at community level are essential for controlling the spread of the epidemic. In addition, the study explores the collaborative governance model and institutional advantages of communities and residents in epidemic prevention and control.

关键词： propagation dynamics complex networks public health events community structure

Facet-dependent activation of oxalic acid over hematite nanocrystals under the irradiation of visible light for efficient degradation of pollutants

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Journal of Environmental Sciences 2024年第8期142卷 204-214页

作者： Zhixiong Yang Yuan Li Xiaotian Wang Jiaming Li Jiquan Wang Gaoke Zhang Hubei Key Laboratory of Mineral Resources Processing and Environment State Key Laboratory of Silicate Materials for ArchitecturesWuhan University of TechnologyWuhan 430070China Hubei Engineering consulting Co. Ltd.Wuhan 430071China

Naturally occurring hematite has been widely studied in the Fenton-like system for water pollutant remediation due to its abundance and ***,its inadequate catalytic activity results in difficulty in effectively degrading pollutants in the catalytic degradation system that it ***,we constructed a photochemical system composed of hematite with{001}facet of high activity facet and low-cost and non-toxic oxalic acid(OA)for the removal of various types of *** removal rate for the degradation of metronidazole,tetracycline hydrochloride,Rhodamine B,and hexavalent chromium by hematite nanoplate with the exposed{001}facet activating OA under visible light irradiation was 4.75,2.25,2.33,and 2.74 times than that by the exposed{110}facet,*** functional theory(DFT)calculation proved that the OA molecule was more easily adsorbed on the{001}facet of hematite than that on the{110}facet,which would favor the formation of the more Fe(Ⅲ)-OA complex and reactive *** addition,the reactive site of metronidazole for the attraction of radicals was identified on the basis of the DFT calculation on the molecular occupied orbitals,and the possible degradation pathway for metronidazole included carbon chain fracture,hydroxyethyl-cleavage,denitrogenation,and ***,this finding may offer a valuable direction in designing an efficient iron-based catalyst based on facet engineering for the improved activity of Fenton-like systems such as OA activation.

关键词： Hematite Facet exposure Oxalic acid activation Fenton-like system Pollutant removal

Reduction behavior of iron ore powder by high-volatile coal in thermogravimetric-gas chromatographic and kinetic analysis

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Journal of Iron and Steel Research International 2024年第1期31卷 92-107页

作者： Rui-meng Shi Qi-yuan Mi Bin Li Xiao Shi Chong Zou Jing Guo Han-jie Guo School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina China International Engineering consulting Corporation Beijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The reduction behavior of iron ore powder by high-volatile coal was investigated,and its kinetic mechanism was *** effect of volatiles in coal on the reduction reaction of iron ore was compared by utilizing a Xinjiang lignite with a high volatile content and its pyrolysis carbon produced by high-temperature pyrolysis to remove volatiles,serving as a *** mass loss and gas composition of the samples during the reduction process were detected using thermo-gravimetric analysis and gas chromatography,and the morphological changes of iron ore powder were observed through scanning electron *** kinetic parameters of the iron oxide reduction reaction were calculated by the Flynn-Ozawa-Wall method,and the kinetic mechanism of volatile participation in the iron oxide reduction reaction was determined through the Coats-Redfern *** results indicate that the coupling effect between the high-volatile coal pyrolysis and reduction reactions occurs during the second stage of the entire coupling process,which corresponds to the late stage of coal pyrolysis with a substantial release of H_(2)and *** volatiles in coal actively participated in the reduction reaction,reducing the initiation temperature of the reaction by around 200℃.The reduction of iron oxides by high-volatile coal was jointly promoted by the"hydrogen cycle"and"carbon cycle",resulting in a higher reduction extent and metallization rate at the end of the *** high-volatile coal was used as the reductant,the average activation energy for the entire process was 76.5 kJ/mol,a significant decrease compared to the employment of pyrolysis carbon without volatiles as the reductant(1167 kJ/mol).

关键词： Direct reduction High-volatile coal Volatile Kinetics Reduction mechanism

Vibration and noise mechanism of a 110 kV transformer under DC bias based on finite element method

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Global Energy Interconnection 2024年第4期7卷 503-512页

作者： Ziyang Li Xujun Lang Bo Yang Xiaolin Liu Hao Wang Zhang Li Shandong Electric Power Engineering consulting Institute Co. Ltd.Jinan 250013P.R.China School of Electrical Engineering Shandong UniversityJinan 250061P.R.China

Global energy and environmental issues are becoming increasingly problematic,and the vibration and noise problem of 110 kV transformers,which are the most widely distributed,have attracted widespread attention from both inside and outside the *** bias is one of the main contributing factors to vibration noise during the normal operation of *** clarify the vibration and noise mechanism of a 110 kV transformer under a DC bias,a multi-field coupling model of a 110 kV transformer was established using the finite element *** electromagnetic,vibration,and noise characteristics during the DC bias process were compared and quantified through field circuit coupling in parallel with the power frequency of AC,harmonic,and DC power *** was found that a DC bias can cause significant distortions in the magnetic flux density,force,and displacement distributions of the core and *** contributions of the DC bias effect to the core and winding are different at Kdc=*** this point,the core approached saturation,and the increase in the core force and displacement ***,the saturation of the core increased the leakage flux,and the stress and displacement of the winding increased *** sound field distribution characteristics of the 110 kV transformer under a DC bias are related to the force *** the DC bias coefficient was 1.25,the noise sound pressure level reached 73.6 dB.

关键词： Transformer DC bias Vibration Noise

Polyvinyl alcohol fiber cement-stabilized macadam:A review and performance evaluation

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 406-423页

作者： Chaohui Wang Jikang Liu Shaochang Chen Feng Chen Zhiwei Gao School of Highway Chang'an UniversityXi'an 710064China Shaanxi Transportation Technology consulting Co. Ltd.Xi'an 710068China School of Information Engineering Xizang Minzu UniversityXianyang 712082China

This review evaluated research results on polyvinyl alcohol fiber cement-stabilized macadam(PVA-FCSM)to further improve the long-term durability of road structures and promote its in-depth study and high-quality *** suitable PVA fiber technical indexes for ordinary cement-stabilized macadam(CSM)were *** difference in the mechanical properties between CSM and PVA-FCSM was *** extent to which PVA fibers enhance the durability of CSM were ***,the mechanism of enhancement of CSM by PVA fibers was ***,the performance of each type of fiber cement-stabilized macadam(FCSM)was compared and *** results indicated that the suggested PVA fiber length and content for CSM were 12-30 mm and 0.6-1.2 kg/m^(3),*** different ages,the mean degree of improvement in the unconfined compressive strength was 14%,20%,and 14%,that in the compressive resilience modulus was 8%,11%,and 6%,and that in the splitting strength was 29%,15%,and 22%,*** different ages,the mean degree of decreased in the dry shrinkage coefficient was 21%,16%,and 15%and that in the temperature shrinkage coefficient(20℃-30℃)was 23%,23%,and 18%,*** coefficients increased with extended curing ***,at the same stress level,PVA-FCSM has a higher fatigue life compared to *** bridging effect,high strength,and high modulus of PVA fiber enhance the strength and anti-cracking of *** recommended fiber type for CSM is PVA fiber.

关键词： Highway and railway engineering PVA fiber cement-stabilized macadam Mechanical performance Durability Enhancement mechanism Performance valuation

A Wind Power Prediction Framework for Distributed Power Grids

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Energy Engineering 2024年第5期121卷 1291-1307页

作者： Bin Chen Ziyang Li Shipeng Li Qingzhou Zhao Xingdou Liu Power Grid Design Institute Shandong Electric Power Engineering Consulting Institute Co.Ltd.Jinan250013China School of Electrical Engineering Shandong UniversityJinan250012China

To reduce carbon emissions,clean energy is being integrated into the power *** power is connected to the grid in a distributed form,but its high variability poses a challenge to grid *** article combines wind turbine monitoring data with numerical weather prediction(NWP)data to create a suitable wind power prediction framework for distributed ***,high-precision NWP of the turbine range is achieved using weather research and forecasting models(WRF),and Kriging interpolation locates predicted meteorological data at the turbine ***,a preliminary predicted power series is obtained based on the fan’s wind speed-power conversion curve,and historical power is reconstructed using variational mode decomposition(VMD)filtering to form input variables in chronological ***,input variables of a single turbine enter the temporal convolutional network(TCN)to complete initial feature extraction,and then integrate the outputs of all TCN layers using Long Short Term Memory Networks(LSTM)to obtain power prediction sequences for all turbine *** proposed method was tested on a wind farm connected to a distributed power grid,and the results showed it to be superior to existing typical methods.

关键词： Wind power prediction distributed power grid WRF mode deep learning variational mode decomposition