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Micromechanism and mathematical model of stress sensitivity in tight reservoirs of binary granular medium

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Petroleum Science 2024年第3期21卷 1780-1795页

作者： Jian-Bang Wu sheng-Lai Yang qiang Li Kun Yang Can Huang Dao-Ping Lv Wei zhou State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China Laboratoire de G eologie Ecole Normale Sup erieure/CNRS UMR8538PSL Research UniversityParis75005France Research Institute of Exploration and Development Xinjiang Oilfield CompanyKaramay834000XinjiangChina

Research on reservoir rock stress sensitivity has traditionally focused on unary granular structures,neglecting the binary nature of real reservoirs,especially tight *** the stresssensitive behavior and mathematical characterization of binary granular media remains a challenging *** this study,we conducted online-NMR experiments to investigate the permeability and porosity evolution as well as stress-sensitive control mechanisms in tight sandy conglomerate *** results revealed stress sensitivity coefficients between 0.042 and 0.098 and permeability damage rates ranging from 65.6%to 90.9%,with an average pore compression coefficient of 0.0168—0.0208 MPa ***-scale compression occurred in three stages:filling,compression,and compaction,with matrix pores playing a dominant role in pore *** stress sensitivity of binary granular media was found to be influenced by the support structure and particle *** stress sensitivity was associated with small fine particle size,high fines content,high uniformity coefficient of particle size,high plastic deformation,and low Young's ***-supported samples exhibited a high irreversible permeability damage rate(average=74.2%)and stress sensitivity coefficients(average=0.089),with pore spaces more *** contrast,grain-supported samples showed low stress sensitivity coefficients(average=0.021)at high stress *** on the experiments,we developed a mathematical model for stress sensitivity in binary granular media,considering binary granular properties and nested interactions using Hertz contact deformation and Poiseuille *** describing the change in activity content of fines under stress,we characterized the non-stationary state of compressive deformation in the binary granular structure and classified the reservoir into three *** model was applied for production prediction using actual data from the Mahu reservoir in China,showing that the e

关键词： Stress sensitivity Binary granular medium Tight reservoir Online-NMR Reservoir energy retention rate

The cluster digging behavior of larvae confers trophic benefits to fitness in insects

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Insect Science 2024年第3期31卷 870-884页

作者： Yujie Wu qiang Wang Weikang Yang sheng Zhang Chuan-Xi Mao Nana He Shaojie zhou Chuanming zhou Wei Liu School of Plant Protection Anhui Agricultural UniversityAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Province Engineering Laboratory for Green Pesticide Development and ApplicationHefeiChina College of Plant Protection Nanjing Agricultural UniversityNanjingChina School of Teacher Education Nanjng Xiaozhuang UniversityNanjingChina State Key Laboratory of Biocatalysis and Enzyme Engineering Hubei Province Key Laboratory of Biotechnology of Chinese Traditional MedicineNational&Local Joint Engineering Research Center of High-throughput Drug Screening TechnologySchool of Life ScienceHubei UniversityWuhanChina

Collective behaviors efficiently impart benefits to a diversity of species ranging from bacteria to *** larvae tend to cluster and form coordinated digging groups under crowded conditions,yet understanding the rules governing this behavior is in its *** primarily took advantage of the Drosophila model to investigate cooperative foraging ***,we report that Drosophila-related species and the black soldier fly have evolved a conserved strategy of cluster digging in food ***,we investigated relative factors,including larval stage,population density,and food stiffness and quality,that affect the cluster digging ***,oxygen supply through the posterior breathing spiracles is necessary for the organization of digging *** importantly,we theoretically devise a mathematical model to accurately calculate how the cluster digging behavior expands food resources by diving depth,cross-section area,and food *** found that cluster digging behavior approximately increases 2.2 fold depth,1.7-fold cross-section area,and 1.9 fold volume than control groups,*** of food sources significantly facilitates survival,larval development,and reproductive success of Drosophila challenged with competition for limited food resources,thereby conferring trophic benefits to fitness in ***,our findings highlight that the cluster digging behavior is a pivotal behavior for their adaptation to food scarcity,advancing a better understanding of how this cooperative behavior confers fitness benefits in the animal kingdom.

关键词： cluster digging determinant development fecundity larvae mathematical model

Design of integral sliding mode guidance law based on disturbance observer

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Journal of Systems Engineering and Electronics 2024年第1期35卷 186-194页

作者： zhou Jianping ZHANG Wenjie zhou Hang LI qiang XIA Qunli School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Informatic Engineering Mianyang Techers’CollegeMianyang 62100China Beijing Institute of Electronic System Engineering Beijing 100854China Beijing Institute of Space Long March Vehicle Beijing 100076China

With the increasing precision of guidance,the impact of autopilot dynamic characteristics and target maneuvering abilities on precision guidance is becoming more and more *** order to reduce or even eliminate the autopilot dynamic operation and the target maneuvering influence,this paper suggests a guidance system model involving a novel integral sliding mode guidance law(ISMGL).The method utilizes the dynamic characteristics and the impact angle,combined with a sliding mode surface scheme that includes the desired line-ofsight angle,line-of-sight angular rate,and second-order differential of the angular *** the same time,the evaluation scenario considere the target maneuvering in the system as the external disturbance,and the non-homogeneous disturbance observer estimate the target maneuvering as a compensation of the guidance *** proposed system’s stability is proven based on the Lyapunov stability *** simulations reveale that ISMGL effectively intercepted large maneuvering targets and present a smaller miss-distance compared with traditional linear sliding mode guidance laws and trajectory shaping guidance ***,ISMGL has a more accurate impact angle and fast convergence speed.

关键词： disturbance observer pilot dynamics integral sliding mode impact angle constraint maneuvering target

Quantitative characterization of fusion state of virgin and aged asphalt using nano-ferrous ferric oxide tracer

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 467-480页

作者： qiang Li Song Liu Huameng Wen zhou zhou College of Civil Engineering Nanjing Forestry UniversityNanjing 210037China School of Transportation Southeast UniversityNanjing 211189China

The exact evaluation of the fusion rate of virgin and aged asphalt is essential to optimize the performance of the recycled asphalt *** fusion rate index was developed by tracing the distribution of tracer asphalt,which contains nano-ferrous ferric oxide(nano-Fe_(3)O_(4))*** fusion simulation tests were performed on three types of asphalt to obtain different fusion states,and fatigue tests were performed to evaluate the influence of the fusion rate on the fatigue life of the recycled *** was found that the tracer asphalt containing 4%nano-Fe_(3)O_(4)shows the optimal trace effect,and the developed fusion rate index can quantitatively characterize the influence of different factors on the fusion state of the recycled *** fusion state is closely related to the fatigue performance of recycled asphalt,and the fusion rate index can fairly evaluate its fatigue *** relationship between the fusion rate and the fatigue life of recycled asphalt depends on the factors that cause the fusion rate *** the influence of the amount of rejuvenator,the fatigue life of recycled asphalt grows exponentially with increasing fusion rate due to enhancement of molecular motion as well as a supplement of lightweight *** the influence of heat preservation treatment,fatigue life increases linearly with increasing fusion *** proposed fusion rate index can be utilized to quantitatively characterize the fusion state of virgin and aged asphalt,thus providing a simple way to guide the practical application of recycled asphalt.

关键词： Recycled asphalt Rejuvenator Tracing technique Fusion rate Fatigue

Viscosity and structure of CaO-BaO-SiO_(2)-Al_(2)O_(3)-based mold slags for continuous casting of high titanium steel with different Tio2 absorption

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Journal of Iron and Steel Research International 2024年第8期31卷 1936-1946页

作者： Ya-tao Cui Xue-you Wang Xu-bin Zhang qiang-qiang Wang sheng-ping He College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

The effect of TiO_(2) absorption into two different CaO-BaO-SiO_(2)-Al_(2)O_(3)-based mold slags from the steel plant on the viscosity,melting performance and microstructure of slags was investigated through the measurement of the viscosity-temperature relationship,melting temperature and Raman *** parameter of the number of non-bridging oxygen per tetrahedrally-coordinated atom(NBO/T)was also calculated to explain the microstructure variation of molten slags with different TiO_(2) *** variation of the actual slag consumption and the depth of the liquid slag in mold was explained through the comparison of the viscosity and the melting temperature of two different *** viscosity of mold slags(basicity=0.6)decreased from 1.1 to 0.68 Pa s with the increase in the Ti0_(2) absorption from 0 to 10%,while that of slags(basicity=0.7)decreased from 0.76 to 0.56 Pa s with the Ti0_(2) absorption from 0 to 6%.The activation energy of both two groups of slags had the tendency to decrease with the increasing TiO_(2) *** network structure of both two groups of slags measured by the Raman spectra showed that the fraction of complex structure units(Q^(1),Q^(2),Q^(3) and A1-O-Al)decreased and simple structure units(Al-O-and Q^(0))increased with the increase in TiO_(2) ***/T also increased with the increase in the TiO2 absorption,indicating that the absorption of TiO_(2) into slags resulted in the destruction of silicate/aluminate ***,the absorption of TiO_(2) into the current CaO-BaO-SiO_(2)-Al_(2)O_(3) mold slags decreased the degree of polymerization of these slags and then led to the decrease of viscosity.

关键词： Mold slag Viscosity Melting temperature Slag consumption Liquid slag depth Structure

Predicting the International Roughness Index of JPCP and CRCP Rigid Pavement:A Random Forest(RF)Model Hybridized with Modified Beetle Antennae Search(MBAS)for Higher Accuracy

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1557-1582页

作者： zhou Ji Mengmeng zhou qiang Wang Jiandong Huang College of Civil and Environmental Engineering Hunan University of Science and EngineeringYongzhou425006China School of Mines China University of Mining and TechnologyXuzhou221116China School of Civil Engineering Guangzhou UniversityGuangzhou510006China

To improve the prediction accuracy of the International Roughness Index(IRI)of Jointed PlainConcrete Pavements(JPCP)and Continuously Reinforced Concrete Pavements(CRCP),a machine learning approach is developed in this study for the modelling,combining an improved Beetle Antennae Search(MBAS)algorithm and Random Forest(RF)*** 10-fold cross-validation was applied to verify the reliability and accuracy of the model proposed in this *** importance scores of all input variables on the IRI of JPCP and CRCP were analysed as *** results by the comparative analysis showed the prediction accuracy of the IRI of the newly developed MBAS and RF hybrid machine learning model(RF-MBAS)in this study is higher,indicated by the RMSE and R values of 0.2732 and 0.9476 for the JPCP as well as the RMSE and R values of 0.1863 and 0.9182 for the *** accuracy of this obtained result far exceeds that of the IRI prediction model used in the traditional Mechanistic-Empirical Pavement Design Guide(MEPDG),indicating the great potential of this developed *** importance analysis showed that the IRI of JPCP and CRCP was proportional to the corresponding input variables in this study,including the total joint faulting cumulated per KM(TFAULT),percent subgrade material passing the 0.075-mm Sieve(P_(200))and pavement surface area with flexible and rigid patching(all Severities)(PATCH)which scored higher.

关键词： Cement pavement JPCP CRCP RF-MBAS IRI

Enhancing Unsupervised Domain Adaptation for Person Re-Identification with the Minimal Transfer Cost Framework

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Computers, Materials & Continua 2024年第9期80卷 4197-4218页

作者： sheng Xu Shixiong Xiang Feiyu Meng qiang Wu Research Institute of Electronic Science and Technology University of Electronic Science and Technology of ChinaChengdu610000China National Key Laboratory of Optical FieldManipulation Science and Technology Chinese Academy of SciencesChengdu610209China

In Unsupervised Domain Adaptation(UDA)for person re-identification(re-ID),the primary challenge is reducing the distribution discrepancy between the source and target *** can be achieved by implicitly or explicitly constructing an appropriate intermediate domain to enhance recognition capability on the target *** construction is difficult due to the absence of intermediate state supervision,making smooth knowledge transfer from the source to the target domain a *** explicitly construct the most suitable intermediate domain for the model to gradually adapt to the feature distribution changes from the source to the target domain,we propose the Minimal Transfer Cost Framework(MTCF).MTCF considers all scenarios of the intermediate domain during the transfer process,ensuring smoother and more efficient domain *** framework mainly includes threemodules:Intermediate Domain Generator(IDG),Cross-domain Feature Constraint Module(CFCM),and Residual Channel Space Module(RCSM).First,the IDG Module is introduced to generate all possible intermediate domains,ensuring a smooth transition of knowledge fromthe source to the target *** reduce the cross-domain feature distribution discrepancy,we propose the CFCM Module,which quantifies the difficulty of knowledge transfer and ensures the diversity of intermediate domain features and their semantic relevance,achieving alignment between the source and target domains by incorporating mutual information and maximum mean *** also design the RCSM,which utilizes attention mechanism to enhance the model’s focus on personnel features in low-resolution images,improving the accuracy and efficiency of person *** proposed method outperforms existing technologies in all common UDA re-ID tasks and improves the Mean Average Precision(mAP)by 2.3%in the Market to Duke task compared to the state-of-the-art(SOTA)methods.

关键词： Person re-identification unsupervised domain adaptation attention mechanism mutual information maximum mean discrepancy

ANALYSIS AND OPTIMIZATION OF A PIEZOELETRIC ACTUATOR COMBINED THE LONGITUDINAL VIBRATION TRANSDUCER WITH THE TRAVELLING WAVE RING

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ANALYSIS AND OPTIMIZATION OF A PIEZOELETRIC ACTUATOR COMBINE...

Evaluating changes in business distribution within urban rail transit hubs in Beijing via Point of Interest (POI) data analysis (2008-2020)

2016年全国压电和声波理论及器件应用研讨会

作者： Long-cheng LI sheng-qiang zhou State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics

Background, Motivation and Objective A piezoelectric actuator combined the longitudinal vibration transducer with the travelling wave ring was been proposed. The relationship of the pre-tightening force to transducer vibration characteristics was found. According to the three characteristics of work mode shape, the work modes of piezoelectric actuator were identified from the modes acquired by ADPL programming. And the structural parameter optimization design of the actuator was studied under ANSYS environment. Finally, a prototype was fabricated on the basis of the optimization design scheme. The experimental result of the prototype was consistent with the simulation analysis. Statement of Contribution/Methods This work is meaningful for several reasons. The pre-tightening force of bolt has an effect on vibration characteristics of the transducer. Especially, the amplitude is influenced obviously. The new modal identification method can identify the working modes from a series of modes. The interference modes are far away from the working modes of the actuator fabricated on the basis of the optimization design scheme. Results As a result, the frequency and amplitude of working mode to transducers changed under different pre-tightening force. The optimal value of assembling pre-tightening force to transducer was 7 Nm. The optimal value of structural parameters(P1, P2, P3, P5) were 3.15 mm, 2.2 mm, 0.57 mm, 34.9 mm respectively. On the basis of the optimization design, the smaller among absolute value of difference between working mode and interference mode(Δ f) was 1888 Hz. The radial amplitude was 0.26μm, the circumferential amplitude was 1.56μm, and the amplitude of Z axis was 2.85μm. Discussion and Conclusions A prototype was fabricated and tested. Two modes of the stator were investigated by a Laser Doppler Vibrometer PSV-300F-B(Polytec). The frequency difference of two modes was both over 1.5 k Hz. The experimental results were consistent with the simulation an

关键词： Pre-tightening force Vibration characteristics Modal identification Optimization design

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Frontiers of Architectural Research 2024年第2期13卷 305-318页

作者： Bo Wan Dongyang Wan qiang sheng School of Architecture and Design Beijing Jiaotong UniversityBeijing 100044China

This paper,set against the backdrop of expanding urban rail networks and dynamic urban development,focuses on the distribution and evolution of commercial Points of Interests(POIs)within the central urban rail transit areas of *** study examines data from four different years-2008,2013,2017,and 2020-to observe the temporal evolution of commercial *** identifies stable explanatory variables affecting the distribution and evolution of commercial POIs,which include rail transit accessibility,characteristics of the working and residential population distribution around stations,and the construction intensity in the vicinity of station *** statistical analysis and model building,relatively stable linear regression equations were established,with R2 values generally maintained above 0.5(except for 2017).The study advances our understanding of the influence of rail transit on urban commercial spaces and how this influence shifts with temporal and urban developmental *** elucidates the correlation between changes in the number of businesses and spatial configuration,offering insights and information for urban planners and policy *** research also serves as a model for exploring the interplay between urban rail transit and commercial spaces in other major cities.

关键词： Urbanrail transit areas Spatial configuration Distributionand evolution of commercial POls