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Integrated Sensing and Communication Enabled Sensing Base Station:System Design,Beamforming,Interference Cancellation and Performance Analysis
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作者 Jiang Wangjun Wei Zhiqing +1 位作者 Feng Zhiyong Chen Xu 《China Communications》 2025年第1期111-127,共17页
This paper studies the sensing base station(SBS)that has great potential to improve the safety of vehicles and pedestrians on roads.SBS can detect the targets on the road with communication signals using the integrate... This paper studies the sensing base station(SBS)that has great potential to improve the safety of vehicles and pedestrians on roads.SBS can detect the targets on the road with communication signals using the integrated sensing and communication(ISAC)technique.Compared with vehicle-mounted radar,SBS has a better sensing field due to its higher deployment position,which can help solve the problem of sensing blind areas.In this paper,key technologies of SBS are studied,including the beamforming algorithm,beam scanning scheme,and interference cancellation algorithm.To transmit and receive ISAC signals simultaneously,a double-coupling antenna array is applied.The free detection beam and directional communication beam are proposed for joint communication and sensing to meet the requirements of beamwidth and pointing directions.The joint timespace-frequency domain division multiple access algorithm is proposed to cancel the interference of SBS,including multiuser interference and duplex interference between sensing and communication.Finally,the sensing and communication performance of SBS under the industrial scientific medical power limitation is analyzed and simulated.Simulation results show that the communication rate of SBS can reach over 100 Mbps and the range of sensing and communication can reach about 500 m. 展开更多
关键词 BEAMFORMING integrated sensing and communication(ISAC) interference cancellation performance analysis sensing base station
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Analysis of auxiliary antenna array effect on performance of wideband noncooperative interference cancellation
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作者 LI Zheyu LI Yaxing +3 位作者 WANG Ze LIANG Jiaqi HE Fangmin MENG Jin 《Journal of Systems Engineering and Electronics》 2025年第5期1188-1201,共14页
In wideband noncooperative interference cancellation,the reference signals obtained through auxiliary antennas are weighted to cancel with the interference signal.The correlation between the reference signal and the i... In wideband noncooperative interference cancellation,the reference signals obtained through auxiliary antennas are weighted to cancel with the interference signal.The correlation between the reference signal and the interference signal determines interference cancellation performance,while the auxiliary antenna array affects the correlation by influencing the amplitude and phase of the reference signals.This paper analyzes the effect of auxiliary antenna array on multiple performances of wideband noncooperative interference cancellation.Firstly,the array received signal model of wideband interference is established,and the weight vector coupled with the auxiliary antennas array manifold is solved by spectral analysis and eigen-subspace decomposition.Then,multiple performances which include cancellation resolution,grating null,wideband interference cancellation ratio(ICR),and convergence rate are quantitatively characterized with the auxiliary antenna array.It is obtained through analysis that the performances mutually restrict the auxiliary antenna array.Higher cancellation resolution requires larger array aperture,but when the number of auxiliary antennas is fixed,larger array aperture results in more grating nulls.When the auxiliary antennas are closer to the main antenna,the wideband ICR is improved,but the convergence rate is reduced.The conclusions are verified through simulation of one-dimensional uniform array and two-dimensional nonuniform array.The experiments of three arrays are compared,and the results conform well with simulation and support the theoretical analysis. 展开更多
关键词 auxiliary antenna array noncooperative interference cancellation wideband interference performance analysis
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Catalytic performance and acidic analysis of chloroaluminate ionic liquid with various impurities in the synthesis of multioctylnaphthalene base oil
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作者 Pengcheng Hu Jinke Yang +1 位作者 Aonan Lai Shufeng Zhou 《Chinese Journal of Chemical Engineering》 2025年第1期218-224,共7页
The effects of the structure and concentration of impurities on the alkylation of naphthalene with 1-octene catalyzed by chloroaluminate ionic liquid(IL)were investigated.The presence of impurities containing oxygen a... The effects of the structure and concentration of impurities on the alkylation of naphthalene with 1-octene catalyzed by chloroaluminate ionic liquid(IL)were investigated.The presence of impurities containing oxygen and nitrogen led to a decrease in the catalytic performance of chloroaluminate IL.As the water concentration increased to 65 mg·g^(-1),the total selectivity of multi-octylnaphthalene gradually decreased to 42.33%,and the average friction coefficient of the multi-octylnaphthalene base oil gradually increased to 0.201.When the concentration of impurities increased to a critical value,the chloroaluminate IL began to deactivate,leading to a decrease in naphthalene conversion.The critical concentrations for ethanolamine,water,methanol,ether,and diisopentyl sulfide were 33 mg·g^(-1),65 mg·g^(-1),67mg·g^(-1),87 mg·g^(-1),and 123 mg·g^(-1),respectively.Impurities with higher basicity resulted in an earlier onset of chloroaluminate IL deactivation.The changes of Lewis and Brønsted acids in chloroaluminate IL under the influence of impurities were investigated using in situ IR and 27Al NMR spectroscopy.2,6-dimethylpyridine as an indicator could detect the changes of Brønsted acid in chloroaluminate IL better,but the changes of Lewis acid were not obvious because of the overlap between the characteristic peaks.2,6-dichloropyridine as an indicator could exclusively detect the changes of Lewis acid in chloroaluminate IL.With the increase inwater concentration,the Lewis acid in chloroaluminate IL was continuously consumed and converted into Brønsted acid,and the Lewis acid gradually decreased,while the Brønsted acid showed a change of increasing first and then decreasing. 展开更多
关键词 Ionic liquid Impurity Naphthalene alkylation Catalytic performance Acidic analysis
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From Wave Energy to Electricity:Functional Design and Performance Analysis of Triboelectric Nanogenerators
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作者 Ying Lou Mengfan Li +2 位作者 Aifang Yu Junyi Zhai Zhong Lin Wang 《Nano-Micro Letters》 2025年第12期33-73,共41页
Triboelectric nanogenerators(TENGs)offer a selfsustaining power solution for marine regions abundant in resources but constrained by energy availability.Since their pioneering use in wave energy harvesting in 2014,nea... Triboelectric nanogenerators(TENGs)offer a selfsustaining power solution for marine regions abundant in resources but constrained by energy availability.Since their pioneering use in wave energy harvesting in 2014,nearly a decade of advancements has yielded nearly thousands of research articles in this domain.Researchers have developed various TENG device structures with diverse functionalities to facilitate their commercial deployment.Nonetheless,there is a gap in comprehensive summaries and performance evaluations of TENG structural designs.This paper delineates six innovative structural designs,focusing on enhancing internal device output and adapting to external environments:high space utilization,hybrid generator,mechanical gain,broadband response,multi-directional operation,and hybrid energy-harvesting systems.We summarize the prevailing trends in device structure design identified by the research community.Furthermore,we conduct a meticulous comparison of the electrical performance of these devices under motorized,simulated wave,and real marine conditions,while also assessing their sustainability in terms of device durability and mechanical robustness.In conclusion,the paper outlines future research avenues and discusses the obstacles encountered in the TENG field.This review aims to offer valuable perspectives for ongoing research and to advance the progress and application of TENG technology. 展开更多
关键词 Triboelectric nanogenerator Functional design Blue energy Electrical performance Sustainability analysis
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Finite element analysis and experimental study on the sealing performance of low-phenyl silicone rubber sealing rings
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作者 Ming Gao Dongkai Li +6 位作者 Kun Liu Shuliang Xu Feng Zhao Ben Guo Anhui Pan Xiao Xie Huanre Han 《Railway Sciences》 2025年第1期123-137,共15页
Purpose–The brake pipe system was an essential braking component of the railway freight trains,but the existing E-type sealing rings had problems such as insufficient low-temperature resistance,poor heat stability an... Purpose–The brake pipe system was an essential braking component of the railway freight trains,but the existing E-type sealing rings had problems such as insufficient low-temperature resistance,poor heat stability and short service life.To address these issues,low-phenyl silicone rubber was prepared and tested,and the finite element analysis and experimental studies on the sealing performance of its sealing rings were carried out.Design/methodology/approach–The low-temperature resistance and thermal stability of the prepared lowphenyl silicone rubber were studied using low-temperature tensile testing,differential scanning calorimetry,dynamic thermomechanical analysis and thermogravimetric analysis.The sealing performance of the lowphenyl silicone rubber sealing ring was studied by using finite element analysis software abaqus and experiments.Findings–The prepared low-phenyl silicone rubber sealing ring possessed excellent low-temperature resistance and thermal stability.According to the finite element analysis results,the finish of the flange sealing surface and groove outer edge should be ensured,and extrusion damage should be avoided.The sealing rings were more susceptible to damage in high compression ratio and/or low-temperature environments.When the sealing effect was ensured,a small compression ratio should be selected,and rubbers with hardness and elasticity less affected by temperature should be selected.The prepared low-phenyl silicone rubber sealing ring had zero leakage at both room temperature(RT)and�508C.Originality/value–The innovation of this study is that it provides valuable data and experience for the future development of the sealing rings used in the brake pipe flange joints of the railway freight cars in China. 展开更多
关键词 Low-phenyl silicone rubber Sealing ring Sealing performance Finite element analysis LEAKAGE
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Comment on"Does ischemic preconditioning enhance sports performance more than placebo or no intervention?A systematic review with meta-analysis"
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作者 Yilin Zhang Hao Kong +2 位作者 Kai Xu Mingyue Yin Yun Xie 《Journal of Sport and Health Science》 2025年第5期70-72,共3页
We highly commend Dr Souza et al.1for their systematic review research.The authors conducted a detailed investigation into the effects of ischemic preconditioning(IPC)on athletic performance,comparing it with placebo ... We highly commend Dr Souza et al.1for their systematic review research.The authors conducted a detailed investigation into the effects of ischemic preconditioning(IPC)on athletic performance,comparing it with placebo and no-intervention conditions.The study found that while IPC demonstrated superior effects over the no-intervention group in certain metrics(e.g.,time to exhaustion),its performance did not significantly surpass that of the placebo group.This suggests that the potential benefits of IPC may partially stem from participants’psychological expectations,or placebo effects.The study also highlighted the significant impact of placebo interventions on athletic performance,emphasizing the importance of distinguishing between placebo and no-intervention conditions in experimental designs. 展开更多
关键词 meta analysis systematic review PLACEBO athletic performance ischemic preconditioning ischemic preconditioning ipc
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Response to the comment on"Does ischemic preconditioning enhance sports performance more than placebo or no intervention?A systematic review with meta-analysis"
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作者 Hiago L.R.Souza Géssyca T.Oliveira +5 位作者 Anderson Meireles Marcelo P.dos Santos Joao G.Vieira Rhai A.Arriel Stephen D.Patterson Moacir Marocolo 《Journal of Sport and Health Science》 2025年第5期134-135,共2页
We sincerely thank the authors of the commentary1 for their thoughtful analysis and constructive critique of our systematic review on ischemic preconditioning(IPC)and placebo effects in exercise capacity and athletic ... We sincerely thank the authors of the commentary1 for their thoughtful analysis and constructive critique of our systematic review on ischemic preconditioning(IPC)and placebo effects in exercise capacity and athletic performance.2Their attention to methodological details,particularly concerning the inclusion and timing of warm-up protocols across studies,is commendable and contributes meaningfully to the ongoing refinement of IPC research in sports science. 展开更多
关键词 meta analysis sports performance placebo effects PLACEBO ischemic preconditioning systematic review ischemic preconditioning ipc
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A novel porous shock absorption layer for tunnels: Shock absorption performance and parameter analysis
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作者 Zhou Tonglai Dong Changsong +1 位作者 Li Shuang Sun Qiangqiang 《Earthquake Engineering and Engineering Vibration》 2025年第2期437-450,共14页
A novel porous shock absorption layer is put forward in this study, and the shock absorption performance of the porous shock absorption layer is evaluated based on three-dimensional pseudo-static analysis. The modifie... A novel porous shock absorption layer is put forward in this study, and the shock absorption performance of the porous shock absorption layer is evaluated based on three-dimensional pseudo-static analysis. The modified reaction acceleration method is adopted and validated in the three-dimensional model. Seven ground motions are selected and the peak ground acceleration is adjusted to 0.2 g, 0.4 g and 0.6 g. The impact of the void ratio and thickness of the porous shock absorption layer is studied, while the surrounding rock grade and tunnel depth are also investigated. The numerical results show that the porous shock absorption layer has good shock absorption performance and can effectively reduce the maximum internal force of the secondary lining, but it cannot reduce the maximum horizontal relative displacement of the secondary lining. The circumferential rubber strip in the porous shock absorption layer will reduce shock absorption performance. The results of parameter analysis indicate that the shock absorption performance of the porous shock absorption layer increases with the increase of the void ratio and thickness, and it has good shock absorption performance under different surrounding rock grades and tunnel depths. 展开更多
关键词 TUNNEL porous shock absorption layer shock absorption performance reaction acceleration method parameter analysis
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Probabilistic characteristic analysis of seismic performance of water distribution system based on quasi-Monte Carlo simulation
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作者 Hou Benwei Yuan Minghao +3 位作者 Diao Kegong Ma Xitao Zhou Baojin Du Xiuli 《Earthquake Engineering and Engineering Vibration》 2025年第2期595-611,共17页
Due to uncertainties in seismic pipeline damage and post-earthquake recovery processes,probabilistic characteristics such as mean value,standard deviation,probability density function,and cumulative distribution funct... Due to uncertainties in seismic pipeline damage and post-earthquake recovery processes,probabilistic characteristics such as mean value,standard deviation,probability density function,and cumulative distribution function provide valuable information.In this study,a simulation-based framework to evaluate these probabilistic characteristics in water distribution systems(WDSs)during post-earthquake recovery is developed.The framework first calculates pipeline failure probabilities using seismic fragility models and then generates damage samples through quasi-Monte Carlo simulations with Sobol’s sequence for faster convergence.System performance is assessed using a hydraulic model,and recovery simulations produce time-varying performance curves,where the dynamic importance of unrepaired damage determines repair sequences.Finally,the probabilistic characteristics of seismic performance indicators,resilience index,resilience loss,and recovery time are evaluated.The framework is applied in two benchmark WDSs with different layouts to investigate the probabilistic characteristics of their seismic performance and resilience.Application results show that the cumulative distribution function reveals the variations in resilience indicators for different exceedance probabilities,and there are dramatic differences among the recovery times corresponding to the system performance recovery targets of 80%,90%,and 100%. 展开更多
关键词 water distribution system probabilistic analysis post-earthquake performance seismic resilience quasi Monte Carlo Sobol’s sequence
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Performance analysis of scramjet including magnetohydrodynamic power generation after combustor
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作者 LIU Chenyuan WU Shaoxun MENG Hao 《推进技术》 北大核心 2025年第8期15-28,共14页
To investigate the overall performance of reverse energy bypass scramjet,firstly a variable spe⁃cific heat method combined with a chemical balance calculation module for combustion products were used to es⁃tablish a b... To investigate the overall performance of reverse energy bypass scramjet,firstly a variable spe⁃cific heat method combined with a chemical balance calculation module for combustion products were used to es⁃tablish a benchmark scramjet performance evaluation model.Based on the test data of typical flying point of Mach 7 with the altitude of 29 km,the reliability of the model was verified.The deviations of parameters such as the to⁃tal pressure loss of combustor between the model and the test data were analyzed.Furtherly,an analytical method for post-combustion magnetohydrodynamic power generation was established;by embedding the above method into the overall performance evaluation model,performance prediction considering the power generation effect was realized.Finally,based on the above model,variety regulations of the inlet and the outlet parameters of the power generation channel and performance parameters including the engine specific impulse and the unit thrust under different enthalpy extraction ratios and load factors were analyzed.It could be concluded that the model can reliably predict the variations of key parameters.As the value of the load factor increases,the value of the conduc⁃tivity required to reach the specified enthalpy extraction ratio first decreases and then increases,which is approxi⁃mately parabolic.In order to reduce the demand for the gas conductivity for MHD power generation,the load fac⁃tor should be around 0.5.When the load factor is 0.4 and the magnetic induction intensity is 2.5 T,if the enthalpy extraction ratio reaches 0.5%,the engine specific impulse performance reduces about 3.58%. 展开更多
关键词 SCRAMJET Energy bypass Magnetohydrodynamic power generation Chemical balance performance evaluation
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Do compression garments enhance running performance?An updated systematic review and meta-analysis
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作者 Wei Wang Yana Wang +7 位作者 Yufeng Zhang Dongyang Si Xingyang Li Qingsong Liang Qianteng Li Lingyan Huang Shutao Wei Yu Liu 《Journal of Sport and Health Science》 2025年第3期109-119,共11页
Background:Despite the wide use of compression garments to enhance athletic running performance,evidence supporting improvements has not been conclusive.This updated systematic review and meta-analysis of randomized c... Background:Despite the wide use of compression garments to enhance athletic running performance,evidence supporting improvements has not been conclusive.This updated systematic review and meta-analysis of randomized controlled trials(RCTs)compared the effects of compression garment wearing with those of non-compression garment wearing(controls)during running on improving running performance.Methods:A comprehensive search was conducted in the electronic databases(Web of Science,EBSCOhost,PubMed,Embase,Scopus,and Cochrane)for RCTs comparing running performance between runners wearing compression garments and controls during running,from inception to September 2024.Independent reviewers screened studies,extracted data,appraised risk of bias(RoB 2)and certainty of evidence(Grading of Recommendations Assessments,Development and Evaluation(GRADE)).Primary outcomes were race time and time to exhaustion.Secondary outcomes covered running speed and race pace,submaximal oxygen uptake,tissue oxygenation,and soft tissue vibration.Randomeffects meta-analyses were conducted to generate pooled estimates,expressed in standardized mean difference(SMD).Subgroup differences of garment,race type,and contact surface were tested in moderator analyses.Results:The search yielded 51 eligible studies comprising 899 participants,of which 33 studies were available for meta-analysis of primary outcomes.Runners wearing compression garments during running showed no significant improvement in race time(SMD=-0.07,95%CI:-0.22 to 0.09;p=0.40)or time to exhaustion(SMD=0.04,95%CI:-0.20 to 0.29;p=0.72).Moderator analyses indicated no effects from garment type,race type,or surface.Secondary outcomes also showed no performance benefits,although compression garments significantly reduced soft tissue vibration(SMD=-0.43,95%CI:-0.70 to-0.15;p<0.01).Certainty of evidence was rated low to very low.Conclusion:Data synthesis of current RCTs offers no updated evidence favoring the support of wearing compression garments during running as a viable strategy for improving running and endurance performance among runners of varying performance levels and types of running races. 展开更多
关键词 RUNNERS performance enhancement SPRINT ENDURANCE
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Does ischemic preconditioning enhance sports performance more than placebo or no intervention?A systematic review with meta-analysis
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作者 Hiago L.R.Souza Géssyca T.Oliveira +5 位作者 Anderson Meireles Marcelo P.dos Santos Joao G.Vieira Rhai A.Arriel Stephen D.Patterson Moacir Marocolo 《Journal of Sport and Health Science》 2025年第2期21-34,共14页
Background:Ischemic preconditioning(IPC)is purported to have beneficial effects on athletic performance,although findings are inconsistent,with some studies reporting placebo effects.The majority of studies have inves... Background:Ischemic preconditioning(IPC)is purported to have beneficial effects on athletic performance,although findings are inconsistent,with some studies reporting placebo effects.The majority of studies have investigated IPC alongside a placebo condition,but without a control condition that was devoid of experimental manipulation,thereby limiting accurate determination of the IPC effects.Therefore,the aims of this study were to assess the impact of the IPC intervention,compared to both placebo and no intervention,on exercise capacity and athletic performance.Methods:A systematic search of PubMed,Embase,SPORTDiscus,Cochrane Library,and Latin American and Caribbean Health Sciences Literature(LILACS)covering records from their inception until July 2023 was conducted.To qualify for inclusion,studies had to apply IPC as an acute intervention,comparing it with placebo and/or control conditions.Outcomes of interest were performance(force,number of repetitions,power,time to exhaustion,and time trial performance),physiological measurements(maximum oxygen consumption,and heart rate),or perceptual measurements(RPE).For each outcome measure,we conducted 3 independent meta-analyses(IPC vs.placebo,IPC vs.control,placebo vs.control)using an inverse-variance random-effects model.The between-treatment effects were quantified by the standardized mean difference(SMD),accompanied by their respective 95%confidence intervals.Additionally,we employed the Grading of Recommendations,Assessment,Development and Evaluation(GRADE)approach to assess the level of certainty in the evidence.Results:Seventy-nine studies were included in the quantitative analysis.Overall,IPC demonstrates a comparable effect to the placebo condition(using a low-pressure tourniquet),irrespective of the subjects'training level(all outcomes presenting p>0.05),except for the outcome of time to exhaustion,which exhibits a small magnitude effect(SMD=0.37;p=0.002).Additionally,the placebo exhibited effects notably greater than the control condition(outcome:number of repetitions;SMD=0.45;p=0.03),suggesting a potential influence of participants'cognitive perception on the outcomes.However,the evidence is of moderate to low certainty,regardless of the comparison or outcome.Conclusion:IPC has significant effects compared to the control intervention,but it did not surpass the placebo condition.Its administration might be influenced by the cognitive perception of the receiving subject,and the efficacy of IPC as an ergogenic strategy for enhancing exercise capacity and athletic performance remains questionable. 展开更多
关键词 DECEPTION Nocebo effects Athletic performance REPERFUSION TOURNIQUETS
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Performance Analysis and Prediction of Rock Cutting with a Rotating Abrasive Water Jet
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作者 Hongxiang Jiang Huihe Zhao +2 位作者 Xiaodi Zhang Zijian Wu Mingjin Zhao 《Chinese Journal of Mechanical Engineering》 2025年第3期119-136,共18页
During the excavation process of deep hard rock tunnels,precutting rock with an abrasive water jet can weaken their strength and improve the efficiency of mining machinery.However,owing to the complex geological envir... During the excavation process of deep hard rock tunnels,precutting rock with an abrasive water jet can weaken their strength and improve the efficiency of mining machinery.However,owing to the complex geological environment,abrasive jets cannot fully utilize their rock-cutting performance.To fully exploit the advantages of high-pressure abrasive water jets,five orthogonal experiments were designed for rocks with significant differences in strength.Experimental research has been conducted on the performance of rotating abrasive waterjet-cutting rocks.Moreover,a neural network prediction model for predicting rock-cutting characteristics is established by comprehensively considering rock mechanics parameters and abrasive water jet parameters.The results show that the cutting depth of rocks with different strengths increases nonlinearly with increasing work pressure of the abrasive water jet.The cutting depth decreases exponentially with increasing cutting velocity.The cutting depth first increases and then decreases with increasing target distance,and the best target distance is between 4 mm and 6 mm.The effect of the target distance on the cutting width of rock is the most significant,but the cutting width of high-strength rock is not sensitive to changes in the working parameters of the abrasive water jet.The average relative errors of BP(backpropagation)neural networks optimized by global optimization algorithms in predicting rock cutting depth and width are 13.3%and 5.4%,respectively.This research combines the working characteristics of mining machinery to study the performance of abrasive waterjet rotary cutting of rocks and constructs a predictive model for the performance of abrasive waterjet cutting of rocks that includes rock strength factors.This provides a new solution for quickly adjusting the working parameters of abrasive water jets according to mining conditions. 展开更多
关键词 Abrasive water jet Cutting rock performance PREDICTION
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Performance Analysis of sCO_(2)Centrifugal Compressor under Variable Operating Conditions
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作者 Jiangbo Wu Siyi Sun Xiaoze Du 《Fluid Dynamics & Materials Processing》 2025年第8期1789-1807,共19页
This study explores the aerodynamic performance and flow field characteristics of supercritical carbon dioxide(sCO_(2))centrifugal compressors under varying operating conditions.In particular,the Sandia main compresso... This study explores the aerodynamic performance and flow field characteristics of supercritical carbon dioxide(sCO_(2))centrifugal compressors under varying operating conditions.In particular,the Sandia main compressor impeller model is used as a reference system.Through three-dimensional numerical simulations,we examine the Mach number distribution,temperature field,blade pressure pulsation spectra,and velocity field evolution,and identify accordingly the operating boundaries ensuring stability and the mechanisms responsible for performance degradation.Findings indicate a stable operating range for mass flow rate between 0.74 and 3.74 kg/s.At the lower limit(0.74 kg/s),the maximum Mach number within the compressor decreases by 28%,while the temperature gradient sharpens,entropy rises notably,and fluid density varies significantly.The maximum pressure near the blades increases by 6%,yet flow velocity near the blades and outlet declines,with a 19%reduction in peak speed.Consequently,isentropic efficiency falls by 13%.Conversely,at 3.74 kg/s,the maximum Mach number increases by 23.7%,with diminished temperature gradients and minor fluid density variations.However,insufficient enthalpy gain and intensified pressure pulsations near the blades result in a 12%pressure drop.Peak velocity within the impeller channel surges by 23%,amplifying velocity gradients,inducing flow separation,and ultimately reducing the pressure ratio from 1.47 to 1.34. 展开更多
关键词 Supercritical carbon dioxide centrifugal compressor variable operating condition analysis aerodynamic characteristics flow field analysis
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The Impact of ESG Integration on REIT Performance:A Comparative Study Based on Quantitative Analysis
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作者 Dazuo Tan 《Journal of World Architecture》 2025年第5期14-21,共8页
This paper systematically examines the impact of environmental,social,and governance(ESG)factors on the financial performance and long-term value of real estate investment trusts(REITs).Adopting comparative analysis a... This paper systematically examines the impact of environmental,social,and governance(ESG)factors on the financial performance and long-term value of real estate investment trusts(REITs).Adopting comparative analysis as the quantitative research method,the paper selects representative cases of ESG-integrated REITs and traditional REITs at home and abroad,constructs a regression model,and compares projects from multiple key value dimensions,including yield,risk-adjusted returns,asset appreciation potential,financing costs,and market liquidity.The study finds that ESG-integrated REITs demonstrate significant advantages in long-term financial performance,risk resilience,and market valuation.Based on these findings,the paper proposes a series of policy recommendations,including improving ESG information disclosure standards,optimizing tax incentive mechanisms,and constructing an ESG evaluation system,to promote the high-quality and sustainable development of China’s REIT market.The paper consists of five parts:introduction of the research problem,theoretical framework,research methods(data sources and model construction),quantitative comparative analysis between ESG-integrated REITs and traditional REITs,and conclusion with recommendations. 展开更多
关键词 Real estate REITS Regression model Long-term performance Sustainable development
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A Comparative Analysis of Green Finance Initiatives and Their Impact on Banking Performance:A Study of RHB Bank,ICBC,and Deutsche Bank
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作者 Xuanyuan Zhang 《Proceedings of Business and Economic Studies》 2025年第3期31-39,共9页
The banking industry is placing increasing emphasis on green finance to address climate change,support sustainable development,and align with environmental,social,and governance(ESG)goals,as well as sustainable invest... The banking industry is placing increasing emphasis on green finance to address climate change,support sustainable development,and align with environmental,social,and governance(ESG)goals,as well as sustainable investments to fund environmentally friendly projects.In an era of growing regulatory pressure and rising demand for sustainability from investors and stakeholders,green finance has become a vital tool for banks to enhance operational efficiency.It can reduce operational costs by financing energy-saving projects,improve asset quality by funding low-risk sustainable projects,and even attract capital from environmentally responsible capital markets.Additionally,green finance helps improve risk management frameworks by financing projects that align with long-term sustainable development objectives.This paper explores the relationship between green finance and the operational efficiency of three major banks—RHB Bank,Industrial and Commercial Bank of China(ICBC),and Deutsche Bank.The article focuses on analyzing how these banks integrate green finance into their strategies and the overall impact of these initiatives on operational performance,primarily cost reduction. 展开更多
关键词 Green finance Operational efficiency Risk management framework Operational performance
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Pilot plant design and technology performance analysis of pervaporation membrane bioreactor with mechanical vapor compression for bioethanol production
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作者 Jingyun Liu Yin Zhang +4 位作者 Wenda Liu Haoji Jiang Lu Han Zeyi Xiao Senqing Fan 《Chinese Journal of Chemical Engineering》 2025年第6期57-66,共10页
A pilot plant integrating pervaporation membrane bioreactor and mechanical vapor compression for bioethanol production was designed and constructed in the study,with a bioethanol production of 300 t·a^(-1).Key eq... A pilot plant integrating pervaporation membrane bioreactor and mechanical vapor compression for bioethanol production was designed and constructed in the study,with a bioethanol production of 300 t·a^(-1).Key equipment in the process were designed based on bench test data.A pilot-scale fermenter with 20 m^(3) in volume,4 m in height and 2.5 m in diameter was designed based on geometric similarity criterion and power equality criterion.An integrated plate-frame membrane module with 105 plates was newly developed.Compared with conventional batch fermentation,the improvement of equipment utilization efficiency and the cell utilization efficiency can be expected as 1.5-2.0 times and 2-10 times,respectively,with waste water reduced by 70% to 85%.The high-exergy energy requirement for pilot plant was 57.5 k W,of which the broth preheater occupied 85.7%,following by the compressor 1.1%,pump1.9% and fermenter agitator 0.3%.The total energy requirement including distillation for producing 1 kg ethanol(95%(mass)) achieved an energy surplus of 15.6 MJ. 展开更多
关键词 Membrane bioreactor Bioethanol production Technology performances Pilot plant Energy requirement
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Performance Analysis of Foamed Fracturing Fluids Based on Microbial Polysaccharides and Surfactants in High-Temperature and High-Salinity Reservoirs
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作者 Zhiqiang Jiang Zili Li +5 位作者 Bin Liang Miao He Weishou Hu Jun Tang Chao Song Nanxin Zheng 《Fluid Dynamics & Materials Processing》 2025年第6期1397-1416,共20页
Microbial polysaccharides,due to their unique physicochemical properties,have been shown to effec-tively enhance the stability of foam fracturing fluids.However,the combined application of microbial polysaccharides an... Microbial polysaccharides,due to their unique physicochemical properties,have been shown to effec-tively enhance the stability of foam fracturing fluids.However,the combined application of microbial polysaccharides and surfactants under high-temperature and high-salinity conditions remain poorly understood.In this study,we innovatively investigate this problem with a particular focus on foam stabilization mechanisms.By employing the Waring blender method,the optimal surfactant-microbial polysaccharide blends are identified,and the foam stability,rheological properties,and decay behavior in different systems under varying conditions are systematically analyzed for the first time.The results reveal that microbial polysaccharides significantly enhance foam stability by improving the viscoelasticity of the liquid films,particularly under high-salinity and high-temperature conditions,leading to notable improvements in both foam stability and sand-carrying capacity.Additionally,scanning electron microscopy(SEM)is used to observe the microstructure of the foam liquid films,demonstrating that the network structure formed by the foam stabilizer within the liquid film effectively inhibits foam coarsening.The Lauryl betaine and Diutan gum blend exhibits outstanding foam stability,superior sand-carrying capacity,and minimal core damage,making(LAB+MPS04)it ideal for applications in enhanced production and reservoir stimulation of unconventional reservoirs. 展开更多
关键词 Foam fracturing fluid microbial polysaccharides synergistic effect stabilization mechanism performance
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Exploring how pay fairness perception affects preschool teachers’ job performance in China: A moderated mediation analysis
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作者 Xiaoying Zeng Ying Liu +1 位作者 YufeiLi Yongping Yu 《Journal of Psychology in Africa》 2025年第1期91-97,共7页
This study constructed a moderated mediation model to examine how the social support received by teachers is associated with their work pay fairness perception in relation to their job satisfaction and job performance... This study constructed a moderated mediation model to examine how the social support received by teachers is associated with their work pay fairness perception in relation to their job satisfaction and job performance.Data were collected from 2411 preschool teachers in China(female=98.01%;mean age=29.12 years,SD=6.28 years).These data were analyzed using structural equation modelling,bootstrapping and latent moderate structural equations.The results indicated that teachers’perception of pay fairness is directly associated with self-rated job performance.Additionally,pay fairness perceptions have an indirect effect on higher job performance through job satisfaction.The social support that teachers perceive moderates the relationship between pay fairness perception and job satisfaction:the more social support teachers receive,the weaker the impact of pay fairness perception on job satisfaction.Thesefindings suggest that teachers’perception of pay fairness is related to their sense of quality of work life,as indicated by their job satisfaction and performance. 展开更多
关键词 pay fairness perception job performance job satisfaction social support preschool teachers
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Analysis of Mechanical Principles of the Unbreakable Doll Performance at Tang Dynasty Night City
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作者 Fan Shi Yuyao Zu 《Journal of Electronic Research and Application》 2025年第4期141-146,共6页
The unbreakable doll performance at Tang Dynasty Night City has become extremely popular,sparking a wave of enthusiasm online.In the performance,actors dressed in elegant Tang Dynasty attire appear as if they have ste... The unbreakable doll performance at Tang Dynasty Night City has become extremely popular,sparking a wave of enthusiasm online.In the performance,actors dressed in elegant Tang Dynasty attire appear as if they have stepped out of a historical painting,gracefully dancing on the unbreakable doll apparatus.Every gesture and expression exudes the unparalleled elegance of the Tang Dynasty.This paper primarily analyzes the mechanical principles behind the Tang Dynasty Night City’s Unbreakable Doll Performance,starting with structural design to examine its mechanical principles and summarize its dynamic mechanical control mechanisms. 展开更多
关键词 Tang Dynasty Night City Unbreakable doll performance Mechanical principles Structural design Mechanical control
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