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Resource Allocation in Multi-User Cellular Networks:A Transformer-Based Deep Reinforcement Learning Approach

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China Communications 2024年第5期21卷 77-96页

作者： Zhao di Zheng Zhong Qin Pengfei Qin Hao Song Bin State Key Laboratory of Integrated Services Networks Xidian University710071China China Academy of Space Technology Beijing 100081China

To meet the communication services with diverse requirements,dynamic resource allocation has shown increasing *** this paper,we consider the multi-slot and multi-user resource allocation(MSMU-RA)in a downlink cellular scenario with the aim of maximizing system spectral efficiency while guaranteeing user *** first model the MSMURA problem as a dual-sequence decision-making process,and then solve it by a novel Transformerbased deep reinforcement learning(TDRL)***,the proposed TDRL approach can be achieved based on two aspects:1)To adapt to the dynamic wireless environment,the proximal policy optimization(PPO)algorithm is used to optimize the multi-slot RA strategy.2)To avoid co-channel interference,the Transformer-based PPO algorithm is presented to obtain the optimal multi-user RA scheme by exploring the mapping between user sequence and resource *** results show that:i)the proposed approach outperforms both the traditional and DRL methods in spectral efficiency and user fairness,ii)the proposed algorithm is superior to DRL approaches in terms of convergence speed and generalization performance.

关键词： dynamic resource allocation multi-user cellular network spectrum efficiency user fairness

Circulating RNA ZFR promotes hepatocellular carcinoma cell proliferation and epithelial-mesenchymal transition process through miR-624-3p/wEE1 axis

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Hepatobiliary & Pancreatic diseases International 2024年第1期23卷 52-63页

作者： Li Zhang Sai He Hao Guan Yao Zhao di Zhang Department of General Surgery the Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004China Department of Breast Cancer Shaanxi Provincial Cancer HospitalXi’an 710000China

Background:Hepatocellular carcinoma(HCC),the most common type of primary liver cancer,is the fourth leading cause of cancer-related deaths *** evidence shows that the expression of circulating RNA ZFR(circZFR)is upregulated in HCC ***,the molecular mechanism of circZFR in HCC is ***:Quantitative reverse transcriptase polymerase chain reaction(qRT-PCR)was employed to detect the expression of circZFR,microRNA-624-3p(miR-624-3p)and wEE1 in HCC tissues and *** R assay and actinomycin D treatment assay were used to analyze the characteristics of *** functional analysis,the capacities of colony formation,cell proliferation,cell apoptosis,migration and invasion were assessed by colony formation assay,5-ethynyl-2-deoxyuridine(EdU)assay,flow cytometry assay and transwell *** blot was used to examine the protein levels of wEE1 and epithelial-mesenchymal transition(EMT)-related *** interactions between miR-624-3p and circZFR or wEE1 were validated by dual-luciferase reporter assay and RNA immunoprecipitation(RIP)*** models were established to determine the role of circZFR in ***:circZFR and wEE1 were upregulated,while miR-624-3p expression was reduced in HCC tissues and *** could sponge miR-624-3p,and wEE1 was a downstream gene of *** of circZFR significantly reduced the malignant behaviors of HCC and that co-transfection with miR624-3p inhibitor restored this *** of wEE1 abolished the inhibitory effect of miR624-3p mimic on HCC ***,circZFR acted as a competitive endogenous RNA(ceRNA)to regulate wEE1 expression by targeting ***,in vivo studies have illustrated that circZFR knockdown inhibited tumor ***:circZFR knockdown reduced HCC cell proliferation,migration and invasion and promoted apoptosis by regulating the miR-624-3p/wEE1 axis,suggesting that the circZFR/miR-624-3p/wEE1 axis might

关键词： Hepatocellular carcinoma circZFR miR-624-3p wEE1 Liver cancer

Impact of wetting-drying cycles and acidic conditions on the soil aggregate stability of yellow‒brown soil

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Journal of Mountain Science 2024年第6期21卷 2075-2090页

作者： XIA Zhenyao NI Yuanzhen LIU Deyu wANG di XIAO Hai Key Laboratory of Geological Hazards on Three Gorges Reservoir Area Ministry of EducationYichang 443002China College of Civil Engineering&Architecture China Three Gorges UniversityYichang 443002China Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of EducationChina Three Gorges UniversityYichang 443002China

Soil aggregate is the basic structural unit of soil,which is the foundation for supporting ecosystem functions,while its composition and stability is significantly affected by the external *** study was conducted to explore the effect of external environment(wetting-drying cycles and acidic conditions)on the soil aggregate distribution and stability and identify the key soil physicochemical factors that affect the soil aggregate *** yellow‒brown soil from the Three Gorges Reservoir area(TGRA)was used,and 8 wetting-drying conditions(0,1,2,3,4,5,10 and 15 cycles)were simulated under 4 acidic conditions(pH=3,4,5 and 7).The particle size distribution and soil aggregate stability were determined by wet sieving method,the contribution of environmental factors(acid condition,wetting-drying cycle and their combined action)to the soil aggregate stability was clarified and the key soil physicochemical factors that affect the soil aggregate stability under wetting-drying cycles and acidic conditions were determined by using the Pearson’s correlation analysis,Partial least squares path modeling(PLS‒PM)and multiple linear regression *** results indicate that wetting-drying cycles and acidic conditions have significant effects on the stability of soil aggregates,the soil aggregate stability gradually decreases with increasing number of wetting-drying cycles and it obviously decreases with the increase of ***,the combination of wetting-drying cycles and acidic conditions aggravate the reduction in the soil aggregate *** wetting-drying cycles,acidic conditions and their combined effect imposes significant impact on the soil aggregate stability,and the wetting-drying cycles exert the greatest *** soil aggregate stability is significantly correlated with the pH,Ca^(2+),Mg^(2+),maximum disintegration index(Mdi)and soil bulk density(SBD).The PLS‒PM and multiple linear regression analysis further reveal that the soil aggre

关键词： Yellow‒brown soil wetting-drying cycles Acidic conditions Soil aggregate stability Soil disintegration

The response of structure and nitrogen removal function of the biofilm on submerged macrophytes to high ammonium in constructed wetlands

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Journal of Environmental Sciences 2024年第8期142卷 129-141页

作者： Xue Jiang Mengmeng wang Shunqing Yang di He Fei Fang Liuyan Yang State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China School of Resources and Environment Anqing Normal UniversityAnqing 246133China

The ammonium exceedance discharge from sewage treatment plants has a great risk to the stable operation of subsequent constructed wetlands(Cws).The effects of high ammonium shocks on submerged macrophytes and epiphytic biofilms on the leaves of submerged macrophytes in Cws were rarely mentioned in previous *** this paper,the 16S rRNA sequencing method was used to investigate the variation of the microbial communities in biofilms on the leaves of Vallisneria natans plants while the growth characteristics of *** plants were measured at different initial ammonium *** results demonstrated that the total chlorophyll and soluble sugar synthesis of *** plants decreased by 51.45%and 57.16%,respectively,and malondialdehyde content increased threefold after8 days if the initial NH_(4)^(+)-N concentration was more than 5 mg/*** density,bacterial quantity,dissolved oxygen,and pH increased with high ammonium *** average removal efficiencies of total nitrogen and NH_(4)^(+)-N reached 73.26%and 83.94%,*** heat map and relative abundance analysis represented that the relative abundances of phyla Proteobacteria,Cyanobacteria,and Bacteroidetes *** numbers of autotrophic nitrifiers and heterotrophic nitrification aerobic denitrification(HNAD)bacteria expanded in *** particular,HNAD bacteria of Flavobacterium,Hydrogenophaga,Acidovorax,Acinetobacter,Pseudomonas,Aeromonas,and Azospira had higher abundances than autotrophic nitrifiers because there were organic matters secreted from declining leaves of *** *** analysis of the nitrogen metabolic pathway showed aerobic denitrification was the main nitrogen removal ***,the nitrification and denitrification bacterial communities increased in epiphytic biofilms on submerged macrophytes in constructed wetlands while submerged macrophytes declined under ammonium shock loading.

关键词： Ammonium shock loading Biofilm Autotrophic nitrifiers Heterotrophic nitrification aerobic denitrification bacteria Submerged macrophyte

A novel strategy of tannery sludge disposal–converting into biochar and reusing for Cr(Ⅵ)removal from tannery wastewater

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Journal of Environmental Sciences 2024年第4期138卷 637-649页

作者： Zhiwei Li di Yu Xingdong wang Xuejiao Liu Zhen Xu Yin wang CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control CAS Haixi Industrial Technology Innovation Center in BeilunNingbo 315830China Key Laboratory of Urban Environment and Health Ningbo Observatio

Tannery sludge with high chromium content has been identified as hazardous solid waste due to its potential toxic *** safety disposal and valorization of the tannery sludge remains a *** this study,the chromium stabilization mechanism was systematically investigated during chromium-rich tannery sludge was converted to biochar and the removal performance of the sludge biochar(SBC)for Cr(Ⅵ)from tannery wastewater was also *** results showed that increase in pyrolysis temperature was conductive to the stabilization of Cr and significant reduction of the proportion of Cr(Ⅵ)in *** was confirmed that the stabilization of chromium mainly was attributed to the embedding of chromium in the C matrix and the transformation of the chromium-containing substances from the amorphous Cr(OH)_(3)to the crystalline state,such as(FeMg)Cr_(2)O_(5).The biochar presented high adsorption capacity of Cr(Ⅵ)at low pH and the maximal theoretical adsorption capacity of SBC produced at 800°C can reach 352 mg Cr(Ⅵ)/g,the process of which can be well expressed by Langmuir adsorption isotherm and pseudo second order *** electrostatic effect and reduction reaction were dominantly responsible for the Cr(Ⅵ)adsorption by ***,this study provided a novel strategy for the harmless disposal and resource utilization for the solid waste containing chromium in leather industry.

关键词： Chromium-rich tannery sludge Pyrolysis Biochar Stabilizationmechanisms Cr(Ⅵ)adsorption

Effect of mesopore spatial distribution of HZSM-5 catalyst on zinc state and product distribution in 1-hexene aromatization

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Chinese Journal of Chemical Engineering 2024年第3期67卷 16-26页

作者： Chenhao wei di Gao Guohao Zhang Liang Zhao Jinsen Gao Chunming Xu The State Key Lab of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China

1-hexene aromatization is a promising technology to convert excess olefin in fluid catalytic cracking(FCC)gasoline to high-value benzene(B),toluene(T),and ***,the increasing market demand of xylene has put forward higher requirements for new generation of *** increasing xylene yield in 1-hexene aromatization,the effect of mesopore structure and spatial distribution on product distribution and Zn loading was *** with different mesopore spatial distribution were prepared by post-treatment of parent HZSM-5 zeolite,including NaOH treatment,tetra-propylammonium hydroxide(TPAOH)treatment,and *** was found the evenly distributed mesopore mainly prolongs the catalyst lifetime by enhancing diffusion properties but reduces the aromatics selectivity,as a result of damage of micropores close to the catalyst *** the selectivity of high-value xylene can be highly promoted when the mesopore is mainly distributed interior the ***,the state of loaded Zn was also affected by mesopores spatial *** the optimized catalyst,the xylene selectivity was enhanced by 12.4%compared with conventional Zn-loaded parent HZSM-5 catalyst at conversion over 99%.It was attributed to the synergy effect of mesopores spatial distribution and optimized acid *** work reveals the role of mesopores in different spatial positions of 1-hexene aromatization catalysts in the reaction process and the influence on metal distribution,as well as their synergistic effect two on the improvement of xylene selectivity,which can improve our understanding of catalyst pore structure and be helpful for the rational design of high-efficient catalyst.

关键词： 1-Hexene aromatization Alkali treatment Xylene selectivity Mesopores Zinc state

Effect of intermittent joint distribution on the mechanical and acoustic behavior of rock masses

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1231-1244页

作者： Shuaiyang Fu Haibo Li Liwang Liu di wu Ben wang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

The mechanical characteristics and acoustic behavior of rock masses are greatly influenced by stochastic *** this study,numerical models of rock masses incorporating intermittent joints with different numbers and dip angles were produced using the finite element method(FEM)with the intrinsic cohesive zone model(ICZM).Then,the uniaxial compressive and wave propagation simulations were *** results indicate that the joint number and dip angle can affect the mechanical and acoustic properties of the *** uniaxial compressive strength(UCS)and wave velocity of rock masses decrease monotonically as the joint number ***,the wave velocity grows monotonically as the joint dip angle *** the joint dip angle is 45°–60°,the UCS of the rock mass is lower than that of other dip *** wave velocity parallel to the joints is greater than that perpendicular to the *** the dip angle of joints remains unchanged,the UCS and wave velocity are positively *** the joint dip angle increases,the variation amplitude of the UCS regarding the wave velocity *** reveal the effect of the joint distribution on the velocity,a theoretical model was also *** to the theoretical wave velocity,the change in wave velocity of models with various joint numbers and dip angles was consistent with the simulation ***,a theoretical indicator(*** tensor)was adopted to analyze the variation of the wave velocity and UCS.

关键词： Stochastic joints Intrinsic cohesive zone model Uniaxial compressive strength(UCS) wave propagation Fabric tensor

Mass transfer enhancement and hydrodynamic performance with wire mesh coupling solid particles in bubble column reactor

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Chinese Journal of Chemical Engineering 2024年第3期67卷 195-205页

作者： Chuanjun di Jipeng Dong Fei Gao Guanghui Chen Pan Zhang Jianlong Li Key Laboratory of Multiphase Flow Reaction and Separation Engineering of Shandong Province College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266043China

It is of vital significance to investigate mass transfer enhancements for chemical engineering *** work focuses on investigating the coupling influence of embedding wire mesh and adding solid particles on bubble motion and gas-liquid mass transfer process in a bubble *** image velocimetry(PIV)technology was employed to analyze the flow field and bubble motion behavior,and dynamic oxygen absorption technology was used to measure the gas-liquid volumetric mass transfer coefficient(kLa).The effect of embedding wire mesh,adding solid particles,and wire mesh coupling solid particles on the flow characteristic and kLa were analyzed and *** results show that the gas-liquid interface area increases by 33%-72%when using the wire mesh coupling solid particles strategy compared to the gas-liquid two-phase flow,which is superior to the other two strengthening *** with the system without reinforcement,kLa in the bubble column increased by 0.5-1.8 times with wire mesh coupling solid particles method,which is higher than the sum of kLa increases with inserting wire mesh and adding particles,and the coupling reinforcement mechanism for affecting gas-liquid mass transfer process was discussed to provide a new idea for enhancing gas-liquid mass transfer.

关键词： Fluid mechanics Bubble Mass transfer wire mesh coupling solid particles Particle image velocimetry Hydrodynamics

Progress in the research on organic piezoelectric catalysts for dye decomposition

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 245-260页

作者： Zhaoning Yang Xiaoxin Shu di Guo Jing wang Hui Bian Yanmin Jia School of Science Xi’an University of Posts and TelecommunicationsXi’an 710121China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China

Organic contaminants have posed a direct and substantial risk to human wellness and the *** recent years,piezo-electric catalysis has evolved as a novel and effective method for decomposing these *** piezoelectric materials offer a wide range of options,most related studies thus far have focused on inorganic materials and have paid little attention to organic *** materials have advantages,such as being lightweight,inexpensive,and easy to process,over inorganic ***,this paper provides a comprehensive review of the progress made in the research on piezoelectric catalysis using organic materials,high-lighting their catalytic efficiency in addressing various *** addition,the applications of organic materials in piezoelectric cata-lysis for water decomposition to produce hydrogen,disinfect bacteria,treat tumors,and reduce carbon dioxide are ***,fu-ture developmental trends regarding the piezoelectric catalytic potential of organic materials are explored.

关键词： piezoelectric catalysis piezoelectric material dye decomposition organic materials