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ON THE MEASURE CONCENTRATION OF INFINITELY DIVISIBLE DISTRIBUTIONS
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作者 Jing ZHANG Zechun HU Wei SUN 《Acta Mathematica Scientia》 2025年第2期473-492,共20页
Let I be the set of all infinitely divisible random variables with finite second moments,I_(0)={X∈I;Var(X)>0},P_(I)=inf_(x∈I)P{|X-E[X]|≤√Var(X)}and P_(I_(0))=inf P{|X-E[X]|<√Var(X)}.Firstly,we prove that P_... Let I be the set of all infinitely divisible random variables with finite second moments,I_(0)={X∈I;Var(X)>0},P_(I)=inf_(x∈I)P{|X-E[X]|≤√Var(X)}and P_(I_(0))=inf P{|X-E[X]|<√Var(X)}.Firstly,we prove that P_(I)≥P_(I_(0))>0.Secondly,we find_(x∈I_(0))the exact values of inf P{|X-E[X]|≤√Var(X)}and inf P{|X-E[X]|<√Var(X)}for the cases that J is the set of all geometric random variables,symmetric geometric random variables,Poisson random variables and symmetric Poisson random variables,respectively.As a consequence,we obtain that P_(I)≤e^(-1)^(∞)∑_(k=0)1/2^(2k)(k!)^(2)≈0.46576 and P_(I_(0))≤e^(-1)≈0.36788. 展开更多
关键词 measure concentration infinitely divisible distribution geometric distribution Poisson distribution Berry-Esseen theorem
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Divisible Semiring Congruences on Distributive Semiring 被引量:2
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作者 李善海 李师正 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第4期406-409,共4页
In this paper, we describe all the divisible semiring congruences on a distributive semiring S and also establish a one_to_one, inclusion_preserving mapping from the set of full, closed, self_conjagate, ideal subsemir... In this paper, we describe all the divisible semiring congruences on a distributive semiring S and also establish a one_to_one, inclusion_preserving mapping from the set of full, closed, self_conjagate, ideal subsemirings of S to the set of all divisible semiring congruences on S. 展开更多
关键词 SEMIRING divisible semiring distributive semiring semiring congruence divisible semiring congruence
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Time to treat the climate and nature crisis as one indivisible global health emergency
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作者 Chris Zielinski on behalf of the authorship group listed below 《Stroke & Vascular Neurology》 SCIE CSCD 2024年第4期325-327,共3页
Over 200 health journals call on the United Nations(UN),political leaders and health professionals to recognise that climate change and biodiversity loss are one indivisible crisis and must be tackled together to pres... Over 200 health journals call on the United Nations(UN),political leaders and health professionals to recognise that climate change and biodiversity loss are one indivisible crisis and must be tackled together to preserve health and avoid catastrophe.This overall environmental crisis is now so severe as to be a global health emergency. 展开更多
关键词 preserve GLOBAL divisible
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Incomplete Group Divisible Designs with Block Size Four and General Index
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作者 Li-dong Wang Hai-rong Kong Hong-juan Liu 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2011年第3期407-418,共12页
In this paper, we investigate the existence of incomplete group divisible designs (IGDDs) with block size four, group-type (g, h) u and general index λ. The necessary conditions for the existence of such a design... In this paper, we investigate the existence of incomplete group divisible designs (IGDDs) with block size four, group-type (g, h) u and general index λ. The necessary conditions for the existence of such a design are that u ≥ 4, g ≥ 3h, λg(u 1) ≡ 0 (mod 3), λ(g h)(u 1) ≡ 0 (mod 3), and λu(u 1)(g 2 h 2 ) ≡ 0 (mod 12). These necessary conditions are shown to be sufficient for all λ≥ 2. The known existence result for λ = 1 is also improved. 展开更多
关键词 group divisible design incomplete group divisible design holy group divisible design
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Neural Codes Constructs Based on Combinatorial Design
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作者 Jin Huang 《Applied Mathematics》 2025年第1期42-60,共19页
Neuroscience (also known as neurobiology) is a science that studies the structure, function, development, pharmacology and pathology of the nervous system. In recent years, C. Cotardo has introduced coding theory into... Neuroscience (also known as neurobiology) is a science that studies the structure, function, development, pharmacology and pathology of the nervous system. In recent years, C. Cotardo has introduced coding theory into neuroscience, proposing the concept of combinatorial neural codes. And it was further studied in depth using algebraic methods by C. Curto. In this paper, we construct a class of combinatorial neural codes with special properties based on classical combinatorial structures such as orthogonal Latin rectangle, disjoint Steiner systems, groupable designs and transversal designs. These neural codes have significant weight distribution properties and large minimum distances, and are thus valuable for potential applications in information representation and neuroscience. This study provides new ideas for the construction method and property analysis of combinatorial neural codes, and enriches the study of algebraic coding theory. 展开更多
关键词 Combinatorial Neural Codes Orthogonal Latin Rectangle Steiner System Group divisible Design Transversal Design
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Research on Euclidean Algorithm and Reection on Its Teaching
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作者 ZHANG Shaohua 《应用数学》 北大核心 2025年第1期308-310,共3页
In this paper,we prove that Euclid's algorithm,Bezout's equation and Divi-sion algorithm are equivalent to each other.Our result shows that Euclid has preliminarily established the theory of divisibility and t... In this paper,we prove that Euclid's algorithm,Bezout's equation and Divi-sion algorithm are equivalent to each other.Our result shows that Euclid has preliminarily established the theory of divisibility and the greatest common divisor.We further provided several suggestions for teaching. 展开更多
关键词 Euclid's algorithm Division algorithm Bezout's equation
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Energy Efficiency Operating Indicator Forecasting and Speed Design Optimization for Polar Ice Class Merchant Vessels
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作者 LU Yu LI Chen−ran +3 位作者 ZHU Xiang−hang LI Shi−an GU Zhu−hao LIU She−wen 《船舶力学》 北大核心 2025年第6期901-911,共11页
In order to accurately forecast the main engine fuel consumption and reduce the Energy Efficiency Operational Indicator(EEOI)of merchant ships in polar ice areas,the energy transfer relationship between ship-machine-p... In order to accurately forecast the main engine fuel consumption and reduce the Energy Efficiency Operational Indicator(EEOI)of merchant ships in polar ice areas,the energy transfer relationship between ship-machine-propeller is studied by analyzing the complex force situation during ship navigation and building a MATLAB/Simulink simulation platform based on multi-environmental resistance,propeller efficiency,main engine power,fuel consumption,fuel consumption rate and EEOI calculation module.Considering the environmental factors of wind,wave and ice,the route is divided into sections,the calculation of main engine power,main engine fuel consumption and EEOI for each section is completed,and the speed design is optimized based on the simulation model for each section.Under the requirements of the voyage plan,the optimization results show that the energy efficiency operation index of the whole route is reduced by 3.114%and the fuel consumption is reduced by 9.17 t. 展开更多
关键词 Energy Efficiency Operational Indicator ice-class ships segment division design optimization
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Design and fabrication of LWDM AWG for data centers with rates above 1.6 Tbps
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作者 HUANG Song CUI Peng-Wei +9 位作者 WANG Yue WANG Liang-Liang ZHANG Jia-Shun MA Jun-Chi ZHANG Chun-Xue GUO Li-Yong YANG Han-Ming WU Yuan-Da AN Jun-Ming SONG Ze-Guo 《红外与毫米波学报》 北大核心 2025年第3期406-412,共7页
A 16-channel arrayed waveguide grating(AWG)with an 800 GHz channel spacing in the O-band has been developed and fabricated based on silica planar lightwave circuit(PLC)technology.By extending the wave⁃length allocatio... A 16-channel arrayed waveguide grating(AWG)with an 800 GHz channel spacing in the O-band has been developed and fabricated based on silica planar lightwave circuit(PLC)technology.By extending the wave⁃length allocation from 8 channels to 16 channels as specified in IEEE 802.3bs,we increased the number of chan⁃nels and boosted transmission capacity to meet the 1.6 Tbps and higher-speed signal transmission requirements for future data centers.Through optimizing the AWG structure,it has achieved insertion loss(IL)better than-1.61 dB,loss uniformity below 0.35 dB,polarization-dependent loss(PDL)below 0.35 dB,adjacent channel cross⁃talk under-20.05 dB,ripple less than 0.75 dB,center wavelength offset under 0.22 nm and 1 dB bandwidth ex⁃ceeding 2.88 nm.The AWG has been successfully measured to transmit 53 Gbaud 4-level pulse amplitude modu⁃lation(PAM4)signal per channel and the total transmission speed can reach over 1.6 Tbps. 展开更多
关键词 local area network wavelength division multiplexing(LWDM) arrayed waveguide grating(AWG) O-band SILICA planar lightwave circuit(PLC)
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Time to treat the climate and nature crisis as one indivisible global health emergency
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作者 Chris Zielinski 《Family Medicine and Community Health》 2023年第4期1-3,共3页
Over 200 health journals call on the United Nations(UN),political leaders and health professionals to recognise that climate change and biodiversity loss are one indivisible crisis and must be tackled together to pres... Over 200 health journals call on the United Nations(UN),political leaders and health professionals to recognise that climate change and biodiversity loss are one indivisible crisis and must be tackled together to preserve health and avoid catastrophe.This overall environmental crisis is now so severe as to be a global health emergency. 展开更多
关键词 preserve GLOBAL divisible
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Changes in World Party Politics in the Context of a “Super Election Year”
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作者 Yao Yibo 《Contemporary World》 2025年第1期39-43,共5页
2024 is a“super election year”with the biggest influence in the world since World War II.About 80 countries covering about 60%of the world's population hold national elections.The number and scale of elections a... 2024 is a“super election year”with the biggest influence in the world since World War II.About 80 countries covering about 60%of the world's population hold national elections.The number and scale of elections are rare in history.The processes and results of many countries'elections are so dramatic,with a series of exchanges,offenses and defenses,which further highlights the trend of intensified political confrontation and social division around the world. 展开更多
关键词 world politics political confrontation social division super election year national elections political confrontation social division
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A Review of Codebooks for CSI Feedback in 5G New Radio and Beyond
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作者 Qin Ziao Yin Haifan 《China Communications》 2025年第2期112-127,共16页
Codebooks have been indispensable for wireless communication standard since the first release of the Long-Term Evolution in 2009.They offer an efficient way to acquire the channel state information(CSI)for multiple an... Codebooks have been indispensable for wireless communication standard since the first release of the Long-Term Evolution in 2009.They offer an efficient way to acquire the channel state information(CSI)for multiple antenna systems.Nowadays,a codebook is not limited to a set of pre-defined precoders,it refers to a CSI feedback framework,which is more and more sophisticated.In this paper,we review the codebooks in 5G New Radio(NR)standards.The codebook timeline and the evolution trend are shown.Each codebook is elaborated with its motivation,the corresponding feedback mechanism,and the format of the precoding matrix indicator.Some insights are given to help grasp the underlying reasons and intuitions of these codebooks.Finally,we point out some unresolved challenges of the codebooks for future evolution of the standards.In general,this paper provides a comprehensive review of the codebooks in 5G NR and aims to help researchers understand the CSI feedback schemes from a standard and industrial perspective. 展开更多
关键词 CODEBOOK CSI 5G NR frequency division duplex Multiple-Input Multiple-Output
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Coral calcium hydride promotes peripheral mitochondrial division and reduces AT-Ⅱ cells damage in ARDS via activation of the Trx2/Myo19/Drp1 pathway
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作者 Qian Li Yang Ang +15 位作者 Qing-Qing Zhou Min Shi Wei Chen Yujie Wang Pan Yu Bing Wan Wanyou Yu Liping Jiang Yadan Shi Zhao Lin Shaozheng Song Manlin Duan Yun Long Qi Wang Wentao Liu Hongguang Bao 《Journal of Pharmaceutical Analysis》 2025年第3期610-624,共15页
Acute respiratory distress syndrome(ARDS)is a common respiratory emergency,but current clinical treatment remains at the level of symptomatic support and there is a lack of effective targeted treatment measures.Our pr... Acute respiratory distress syndrome(ARDS)is a common respiratory emergency,but current clinical treatment remains at the level of symptomatic support and there is a lack of effective targeted treatment measures.Our previous study confirmed that inhalation of hydrogen gas can reduce the acute lung injury of ARDS,but the application of hydrogen has flammable and explosive safety concerns.Drinking hydrogen-rich liquid or inhaling hydrogen gas has been shown to play an important role in scavenging reactive oxygen species and maintaining mitochondrial quality control balance,thus improving ARDS in patients and animal models.Coral calcium hydrogenation(CCH)is a new solid molecular hydrogen carrier prepared from coral calcium(CC).Whether and how CCH affects acute lung injury in ARDS remains unstudied.In this study,we observed the therapeutic effect of CCH on lipopolysaccharide(LPS)induced acute lung injury in ARDS mice.The survival rate of mice treated with CCH and hydrogen inhalation was found to be comparable,demonstrating a significant improvement compared to the untreated ARDS model group.CCH treatment significantly reduced pulmonary hemorrhage and edema,and improved pulmonary function and local microcirculation in ARDS mice.CCH promoted mitochondrial peripheral division in the early course of ARDS by activating mitochondrial thioredoxin 2(Trx2),improved lung mitochondrial dysfunction induced by LPS,and reduced oxidative stress damage.The results indicate that CCH is a highly efficient hydrogen-rich agent that can attenuate acute lung injury of ARDS by improving the mitochondrial function through Trx2 activation. 展开更多
关键词 Coral calcium hydrogenation ARDS Mitochondria Peripheral division Trx2
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Group formation tracking for heterogeneous linear multi-agent systems under switching topologies
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作者 Shiyu Zhou Dong Sun 《Journal of Automation and Intelligence》 2025年第2期108-114,共7页
This article investigates the time-varying output group formation tracking control(GFTC)problem for heterogeneous multi-agent systems(HMASs)under switching topologies.The objective is to design a distributed control s... This article investigates the time-varying output group formation tracking control(GFTC)problem for heterogeneous multi-agent systems(HMASs)under switching topologies.The objective is to design a distributed control strategy that enables the outputs of the followers to form the desired sub-formations and track the outputs of the leader in each subgroup.Firstly,novel distributed observers are developed to estimate the states of the leaders under switching topologies.Then,GFTC protocols are designed based on the proposed observers.It is shown that with the distributed protocol,the GFTC problem for HMASs under switching topologies is solved if the average dwell time associated with the switching topologies is larger than a fixed threshold.Finally,an example is provided to illustrate the effectiveness of the proposed control strategy. 展开更多
关键词 Formation tracking Group division Switching topologies Multi-agent systems
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Transcriptome analysis provides new insights into the berry size in‘Summer Black'grape under a two-crop-a-year cultivation system
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作者 Peiyi Ni Shengdi Yang +6 位作者 Yunzhang Yuan Chunyang Zhang Hengliang Zhu Jing Ma Shuangjiang Li Guoshun Yang Miao Bai 《Horticultural Plant Journal》 2025年第4期1469-1482,共14页
Southern China has high temperatures and receives concentrated rainfall;therefore,the two-crop-a-year cultivation system has been applied to grape production so as to resolve the problem of relative seasonal surplus o... Southern China has high temperatures and receives concentrated rainfall;therefore,the two-crop-a-year cultivation system has been applied to grape production so as to resolve the problem of relative seasonal surplus of grape yield.However,a common issue associated with this technique is the tendency of the second season fruits to be smaller than the first season fruits.We here used the first and second season fruits of‘Summer Black'at different ripening stages as research materials.Phenotypic and histological analyses revealed fewer cell number occurring between 7 and 14 days post anthesis(DPA)in the second season fruits,which ultimately resulted in a smaller fruit size compared with the first season fruits.To unravel the mechanism underlying this phenomenon,first and second season fruits of four time periods(7,14,21,and 28 DPA)were selected for RNA-seq analysis.This analysis identified 10431 differentially expressed genes(DEGs).These DEGs were classified into 9 clusters through GO and KEGG enrichment analyses.Then the time-ordered gene co-expression network(TO-GCN)analysis with the breadth-first search algorithm showed that DEGs in the GCN were divided into 8 levels.The DEGs of early berry development(L1-L3)were enriched in heat stress-and cell division-related pathways.The field investigation of effective accumulated temperature confirmed that the growth and development of the second season fruits were subjected to high temperature stress during 7-14 DPA.Moreover,based on the results of interactive analysis of TO-GCN and transcriptional regulation prediction of L1-L3 genes,we constructed a unique hierarchical regulatory network for the heat stress regulation of berry size.The expression level of 5 candidate genes was verified through qRT-PCR.Vitvi10g00469(HSFB2A),Vitvi16g00982(HSFB2A),Vitvi02g00387(HSFB2B),Vitvi15g01542(NTL9),and Vitvi06g00592(DIVARICATA)were upregulated in 7-14 DPA,whereas Vitvi18g00777(HSFB4)was downregulated in 7 DPA.These results suggest that during intense cell division,heat stress might act as a major factor causing a reduction in cell number,thereby ultimately resulting in the smaller size of the second season fruits. 展开更多
关键词 GRAPE Second season fruits Berry size Cell division Heat stress
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Role of active stress and actin alignment in cell division:A hydrodynamic perspective
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作者 Kunhao Dong Menglong Feng Rui Ma 《Chinese Physics B》 2025年第8期59-71,共13页
Cell division is a fundamental biological process in which a parent cell divides into two daughter cells.The cell cortex,a thin layer primarily composed of actin filaments and myosin motors beneath the plasma membrane... Cell division is a fundamental biological process in which a parent cell divides into two daughter cells.The cell cortex,a thin layer primarily composed of actin filaments and myosin motors beneath the plasma membrane,plays a critical role in ensuring proper cell division.In this study,we apply a hydrodynamic model to describe the actin cortex as an active nematic surface,incorporating orientational order arising from actin filament alignment and anisotropic active stress produced by myosin motors.By analyzing the linearized dynamics,we investigate how shape,flow,and stress regulators evolve over time when the surface deviates slightly from a sphere.Our findings reveal that the active alignment of actin filaments,often overlooked in previous studies,is crucial for successful division.Furthermore,we demonstrate that a cortical chiral flow naturally emerges as a consequence of this active alignment.Overall,our results provide a mechanistic explanation for key phenomena observed during cell division,offering new insights into the role of active stress and filament alignment in cortical dynamics. 展开更多
关键词 cell division actin cortex nematic surface chiral flow
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BTNL9 exerts anti-cancer effects by inhibiting CDC20 to induce G2/M arrest in pancreatic cancer
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作者 Mao Xiao Zhi-Yan Luo +2 位作者 Ai-Ru Yu Ke Xu Wei Zhou 《World Journal of Gastrointestinal Oncology》 2025年第7期364-379,共16页
BACKGROUND Pancreatic cancer(PC)is an aggressive malignancy.As a member of the BTN/BTNL family,BTNL9 has been identified as a tumor suppressor in breast cancer,lung adenocarcinoma,and colon cancer;however,its role and... BACKGROUND Pancreatic cancer(PC)is an aggressive malignancy.As a member of the BTN/BTNL family,BTNL9 has been identified as a tumor suppressor in breast cancer,lung adenocarcinoma,and colon cancer;however,its role and underlying mechanisms in PC remain to be elucidated.AIM To investigate the role of BTNL9 in the pathogenesis and development of PC.METHODS The difference of BTNL9 expression in cancer and adjacent normal tissues was analyzed by RNA sequencing data from a public database and tissue microarray detection.The relationship between BTNL9 expression and the prognosis of patients was also studied.The effects of BTNL9 on proliferation,metastasis,and cell cycle of PC cells were investigated by phenotypic experiments.The mechanism was investigated by RNA sequencing,western blotting,and immunofluorescence detection.RESULTS The mRNA and protein levels of BTNL9 in PC tissues were downregulated compared with normal tissues.Based on survival data from The Cancer Genome Atlas and tissue microarray,BTNL9 was an independent influencing factor for overall survival,and its low expression predicted a shortened overall survival of patients.In vitro,BTNL9 could inhibit cell proliferation and metastasis in both PANC-1 and MIA PaCa-2 cells and induce cell cycle arrest in G2/M phases.Downregulation of BTNL9 could activate the cell cycle signaling pathway.Furthermore,overexpression of BTNL9 could significantly inhibit the expression of cell division cycle 20(CDC20).Rescue experiments demonstrated that overexpression of CDC20 reversed the effect of BTNL9 on the proliferation,metastasis,and cell cycle of PC cells.CONCLUSION The expression of BTNL9 was downregulated in PC,and it has the prediction ability for prognosis.Functionally,BTNL9 exerted an anti-cancer effect by suppressing downstream CDC20 expression in PC. 展开更多
关键词 Pancreatic cancer Butyrophilin like 9 Cell division cycle 20 Cell cycle PROGNOSIS
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Development of a Model Material Suitable for Reservoir Landslide Model Tests
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作者 Minghao Miao Huiming Tang +4 位作者 Sha Lu Changdong Li Kun Fang Yixiao Gu Chunyan Tang 《Journal of Earth Science》 2025年第5期1989-2004,共16页
In the physical model test of landslides,the selection of analogous materials is the key,and it is difficult to consider the similarity of mechanical properties and seepage performance at the same time.To develop a mo... In the physical model test of landslides,the selection of analogous materials is the key,and it is difficult to consider the similarity of mechanical properties and seepage performance at the same time.To develop a model material suitable for analysing the deformation and failure of reservoir landslides,based on the existing research foundation of analogous materials,5 materials and 5 physical-mechanical parameters were selected to design an orthogonal test.The factor sensitivity of each component ratio and its influence on the physical-mechanical indices were studied by range analysis and stepwise regression analysis,and the proportioning method was determined.Finally,the model material was developed,and a model test was carried out considering Huangtupo as the prototype application.The results showed that(1)the model material composed of sand,barite powder,glass beads,clay,and bentonite had a wide distribution of physical-mechanical parameters,which could be applied to model tests under different conditions;(2)the physical-mechanical parameters of analogous materials matched the application prototype;and(3)the mechanical properties and seepage performance of the model material sample met the requirements of reservoir landslide model tests,which could be used to simulate landslide evolution and analyse the deformation process. 展开更多
关键词 analogous material physical model test reservoir landslide range analysis stepwise regression stage division PIVlab LANDSLIDES engineering geology
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Joint Resource Allocation and Trajectory Optimization in a UAV-Enabled OFDMA Network
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作者 Chen Yong Zhang Xianyu +2 位作者 Zhang Yu Wang Wei Yang Hua 《China Communications》 2025年第10期72-87,共16页
Due to the extraordinary advantages,un-manned aerial vehicle(UAV)can be utilized as aerial base station(BS)to provide temporary and on-demand wireless connections for user equipments in the cover-age area.This article... Due to the extraordinary advantages,un-manned aerial vehicle(UAV)can be utilized as aerial base station(BS)to provide temporary and on-demand wireless connections for user equipments in the cover-age area.This article specifically considers the UAV-enabled orthogonal frequency division multiple access(OFDMA)wireless communication network.Consid-ering a practical scenario,a joint resource allocation and trajectory design optimization problem with the constraints on UAV mobility,limited total resource and backhaul link rate has been formulated,which aims to maximize the minimum achievable average rate of the users.To tackle the coupling and non-convexity of the proposed problem,an efficient opti-mization algorithm has been proposed based on alter-nating optimization,successive convex approximation and introducing slack variable techniques.Simulation results illustrate that the proposed optimization algo-rithm can effectively improve the system performance.Also,the numerical results unveil that joint optimiza-tion is superior to baseline schemes. 展开更多
关键词 joint optimization orthogonal frequency division multiple access resource allocation spectral efficiency trajectory design unmanned aerial vehicle
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TBM big data preprocessing method in machine learning and its application to tunneling
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作者 Xinyue Zhang Xiaoping Zhang +3 位作者 Quansheng Liu Weiqiang Xie Shaohui Tang Zengmao Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期4762-4783,共22页
The big data generated by tunnel boring machines(TBMs)are widely used to reveal complex rock-machine interactions by machine learning(ML)algorithms.Data preprocessing plays a crucial role in improving ML accuracy.For ... The big data generated by tunnel boring machines(TBMs)are widely used to reveal complex rock-machine interactions by machine learning(ML)algorithms.Data preprocessing plays a crucial role in improving ML accuracy.For this,a TBM big data preprocessing method in ML was proposed in the present study.It emphasized the accurate division of TBM tunneling cycle and the optimization method of feature extraction.Based on the data collected from a TBM water conveyance tunnel in China,its effectiveness was demonstrated by application in predicting TBM performance.Firstly,the Score-Kneedle(S-K)method was proposed to divide a TBM tunneling cycle into five phases.Conducted on 500 TBM tunneling cycles,the S-K method accurately divided all five phases in 458 cycles(accuracy of 91.6%),which is superior to the conventional duration division method(accuracy of 74.2%).Additionally,the S-K method accurately divided the stable phase in 493 cycles(accuracy of 98.6%),which is superior to two state-of-the-art division methods,namely the histogram discriminant method(accuracy of 94.6%)and the cumulative sum change point detection method(accuracy of 92.8%).Secondly,features were extracted from the divided phases.Specifically,TBM tunneling resistances were extracted from the free rotating phase and free advancing phase.The resistances were subtracted from the total forces to represent the true rock-fragmentation forces.The secant slope and the mean value were extracted as features of the increasing phase and stable phase,respectively.Finally,an ML model integrating a deep neural network and genetic algorithm(GA-DNN)was established to learn the preprocessed data.The GA-DNN used 6 secant slope features extracted from the increasing phase to predict the mean field penetration index(FPI)and torque penetration index(TPI)in the stable phase,guiding TBM drivers to make better decisions in advance.The results indicate that the proposed TBM big data preprocessing method can improve prediction accuracy significantly(improving R2s of TPI and FPI on the test dataset from 0.7716 to 0.9178 and from 0.7479 to 0.8842,respectively). 展开更多
关键词 Tunnel boring machine Big data preprocessing Division of tunneling cycle Tunneling resistance Machine learning
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A Review on the Theory and Principle of the Division of "Production-Living-Ecology" Spaces
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作者 Yongxin WANG Xiaowei SHI Linsen HE 《Asian Agricultural Research》 2025年第7期1-6,共6页
From the concept of the "Production-Living-Ecology" Spaces, this paper sorts out the theoretical basis, division principles, and division methods of the "Production-Living-Ecology" Spaces, and then... From the concept of the "Production-Living-Ecology" Spaces, this paper sorts out the theoretical basis, division principles, and division methods of the "Production-Living-Ecology" Spaces, and then proposes future prospects for them. The integration of theory and practice of "Production-Living-Ecology" Spaces is currently in a stage of in-depth exploration and practical application. Future research should fully recognize the importance and necessity of theoretical research on "Production-Living-Ecology" Spaces under the new situation, and consolidate the theoretical foundation for research on the development and protection of territorial space in the new era. 展开更多
关键词 "Production-Living-Ecology"Spaces Division methods Territorial spatial planning Ecological priority
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