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Gas Production and Reservoir Settlement in NGH Deposits under Horizontal-Well Depressurization
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作者 Lijia Li Shu Liu +1 位作者 Xiaoliang Huang Zhilin Qi 《Fluid Dynamics & Materials Processing》 2026年第1期118-137,共20页
Identifying geohazards such as landslides and methane leakage is crucial during gas extraction from natural gas hydrate(NGH)reservoirs,and understanding reservoir settlement behavior is central to this assessment.Hori... Identifying geohazards such as landslides and methane leakage is crucial during gas extraction from natural gas hydrate(NGH)reservoirs,and understanding reservoir settlement behavior is central to this assessment.Horizontal wells can enlarge the pressure relief zone within the formation,improving single-well productivity,and are therefore considered a promising approach for NGH development.This study examines the settlement response of hydrate-bearing sediments during depressurization using horizontal wells.A fully coupled thermal,hydraulic,mechanical,and chemical(THMC)model with representative reservoir properties(Shenhu region in the South China Sea)is presented accordingly.The simulations show that lower production pressures,while increasing gas output,also intensify formation settlement.The maximum difference in settlement between the lowest and highest production pressures reaches 0.016 m,contributing to more pronounced differential subsidence.Optimal well placement,specifically targeting a low-saturation hydrate zone containing free gas and situated adjacent to a high-saturation hydrate layer,markedly improves both gas production rate and cumulative yield,while reducing overall settlement and limiting changes in effective stress. 展开更多
关键词 Hydrate bearing sediment horizontal well DEPRESSURIZATION reservoir settlement
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Graph-Based Unified Settlement Framework for Complex Electricity Markets:Data Integration and Automated Refund Clearing
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作者 Xiaozhe Guo Suyan Long +4 位作者 Ziyu Yue Yifan Wang Guanting Yin Yuyang Wang Zhaoyuan Wu 《Energy Engineering》 2026年第1期56-90,共35页
The increasing complexity of China’s electricity market creates substantial challenges for settlement automation,data consistency,and operational scalability.Existing provincial settlement systems are fragmented,lack... The increasing complexity of China’s electricity market creates substantial challenges for settlement automation,data consistency,and operational scalability.Existing provincial settlement systems are fragmented,lack a unified data structure,and depend heavily on manual intervention to process high-frequency and retroactive transactions.To address these limitations,a graph-based unified settlement framework is proposed to enhance automation,flexibility,and adaptability in electricity market settlements.A flexible attribute-graph model is employed to represent heterogeneousmulti-market data,enabling standardized integration,rapid querying,and seamless adaptation to evolving business requirements.An extensible operator library is designed to support configurable settlement rules,and a suite of modular tools—including dataset generation,formula configuration,billing templates,and task scheduling—facilitates end-to-end automated settlement processing.A robust refund-clearing mechanism is further incorporated,utilizing sandbox execution,data-version snapshots,dynamic lineage tracing,and real-time changecapture technologies to enable rapid and accurate recalculations under dynamic policy and data revisions.Case studies based on real-world data from regional Chinese markets validate the effectiveness of the proposed approach,demonstrating marked improvements in computational efficiency,system robustness,and automation.Moreover,enhanced settlement accuracy and high temporal granularity improve price-signal fidelity,promote cost-reflective tariffs,and incentivize energy-efficient and demand-responsive behavior among market participants.The method not only supports equitable and transparent market operations but also provides a generalizable,scalable foundation for modern electricity settlement platforms in increasingly complex and dynamic market environments. 展开更多
关键词 Electricity market market settlement data model graph database market refund clearing
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BIM-Based Visualization System for Settlement Warning in Multi-Purpose Utility Tunnels(MUTs)
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作者 Ping Wu Jie Zou +1 位作者 Wangxin Li Yidong Xu 《Structural Durability & Health Monitoring》 2026年第1期283-301,共19页
The existing 2D settlement monitoring systems for utility tunnels are heavily reliant on manual interpretation of deformation data and empirical predictionmodels.Consequently,early anomalies(e.g.,minor cracks)are ofte... The existing 2D settlement monitoring systems for utility tunnels are heavily reliant on manual interpretation of deformation data and empirical predictionmodels.Consequently,early anomalies(e.g.,minor cracks)are often misjudged,and warnings lag by about 24 h without automated spatial localization.This study establishes a technical framework for requirements analysis,architectural design,and data-integration protocols.Revit parametric modelling is used to build a 3D tunnel model with structural elements,pipelines and 18 monitoring points(for displacement and joint width).Custom Revit API code integrated real-time sensor data into the BIM platform via an automated pipeline.The system achieved a spatial accuracy of±1 mm in locating deformation hotspots.Notifications are triggered within 10 s of anomaly detection,and the system renders 3D risk propagation paths in real-time.Realtime 3D visualization of risk propagation paths is also facilitated.The efficacy of the solution was validated in a Ningbo utility tunnel project,where it was demonstrated that it eliminates human-dependent judgment errors and reduces warning latency by 99.9%compared to conventional methods.The BIM-IoT integrated approach,which enables millimetre-level precision in risk identification and near-instantaneous response,establishes a new paradigm for intelligent infrastructure safety management. 展开更多
关键词 Multi-purpose utility tunnels settlement monitoring BIM-based visualization WARNING
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Microseismic characteristics and settlement analysis of concrete face rockfilldams on deep overburden layers during the fillingprocess
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作者 Haoyu Mao Nuwen Xu +5 位作者 Peiwei Xiao Guo Liao Feng Gao Xiang Zhou Xinchao Ding Biao Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1034-1048,共15页
Many hydropower projects have been constructed in Southwest China with the strategic goal of achieving carbon neutrality.Most of these hydropower projects utilize concrete face rockfilldams(CFRDs)built on a deep overb... Many hydropower projects have been constructed in Southwest China with the strategic goal of achieving carbon neutrality.Most of these hydropower projects utilize concrete face rockfilldams(CFRDs)built on a deep overburden layer.The deep overburden layer causes uneven settlement between the overburden layer and the dam,which poses a serious threat to the safety of both the construction and operation of the dam.In this study,microseismic(MS)monitoring technology was employed for the firsttime in the fieldof dam fillingengineering,allowing for the real-time monitoring of microfracture in the bedrock during dam construction.The time-frequency analysis method was used to summarize the MS waveform characteristics induced by dam filling.The fracture mechanism of bedrock was revealed,and the relationships among slope deformation,dam settlement,and MS activity were analyzed.The following research results have been obtained.The MS signal induced by dam fillinghas low energy and amplitude,short duration,and high frequency.The fracture of the bedrock was mainly shear failure.MS monitoring can predict deformation during blasting excavation and capture the large settlement that may occur during dam fillingin advance.Research findingshave demonstrated the significantapplication value of MS monitoring technology in predicting the risk of dam settlement and provide a reference for similar projects. 展开更多
关键词 Concrete face rockfilldam(CFRD) Deep overburden layer settlement Microseismic(MS)monitoring Dam filling
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Improving service accessibility and equity for sustainable development goals without newly facilities by rural settlement reconstruction
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作者 Caihui Cui Zhigang Han +3 位作者 Feng Liu Jingru Ma Haiying Wang Xiang Chen 《Geography and Sustainability》 2025年第1期105-117,共13页
Ensuring the provision of accessible,affordable,and high-quality public services to all individuals aligns with one of the paramount aims of the United Nations’Sustainable Development Goals(SDGs).In the face of esca ... Ensuring the provision of accessible,affordable,and high-quality public services to all individuals aligns with one of the paramount aims of the United Nations’Sustainable Development Goals(SDGs).In the face of esca lating urbanization and a dwindling rural populace in China,reconstructing rural settlements to enhance public service accessibility has become a fundamental strategy for achieving the SDGs in rural areas.However,few stud ies have examined the optimal methods for rural settlement reconstruction that ensure accessible and equitable public services while considering multiple existing facilities and service provisions.This paper focuses on rural settlement reconstruction in the context of the SDGs,employing an inverted MCLP-CC(maximal coverage loca tion problem for complementary coverage)model to identify optimal rural settlements and a rank-based method for their relocation.Conducted in Changyuan,a county-level city in Henan Province,China,this study observed significant enhancements in both accessibility and equity following rural settlement reconstruction by utilizing the MH3SFCA(modified Huff 3-step floating catchment area)and the spatial Lorenz curve method.Remarkably,these improvements were achieved without the addition of new facilities,with the accessibility increasing by 44.21%,4.97%,and 3.11%;Gini coefficients decreasing by 19.53%,1.64%,and 3.18%;Ricci-Schutz coef-ficients decreasing by 21.09%,2.09%,and 4.33%for educational,medical,and cultural and sports facilities,respectively.It indicated that rural settlement reconstruction can bolster the accessibility and equity of public ser-vices by leveraging existing facilities.This paper provides a new framework for stakeholders to better reconstruct rural settlements and promote sustainable development in rural areas in China. 展开更多
关键词 SDGs EQUITY ACCESSIBILITY Rural settlement reconstruction Spatial optimization
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Influence of subgrade settlement on the dynamic properties of a medium and low speed maglev train-track-ground girder system
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作者 Wang Dangxiong Ji Keting +3 位作者 Weng Xiaolong Wu Fa Ning Zikai Wang Chongguang 《Earthquake Engineering and Engineering Vibration》 2025年第4期1157-1174,共18页
A ground girder is laid on the preprocessed subgrade by gravity compaction and integrally uniformly supported by subgrade in maglev transit.The settlement of the maglev subgrade inevitably affects the vibration state ... A ground girder is laid on the preprocessed subgrade by gravity compaction and integrally uniformly supported by subgrade in maglev transit.The settlement of the maglev subgrade inevitably affects the vibration state of the medium and low speed maglev coupled system by the additional deformation of the maglev track.This study investigated the dynamic properties of the coupled vibration system affected by the subgrade settlement.First,a theoretical coupled vibration model of a maglev train-track-ground girder system with uneven subgrade settlement was proposed and verified.Then,the effect mechanism of the coupled system caused by the uneven subgrade settlement was explored.Finally,settlement types and subgrade support voiding were examined.The analysis showed that the uneven subgrade settlement considerably increased the dynamic responses of the levitation control system and maglev vehicle while having a minor influence on those of the track-ground girder.The influence of a single ground girder settling was the strongest,and adjacent sides’settling of two ground girders was the weakest for the vibration of a maglev train.An extremely large uneven settlement exceeding 6 mm led to active levitation control system instability.The subgrade support voiding enlarged the vehicle-induced vibration of the track ground girder. 展开更多
关键词 maglev transit ground girder vibration system uneven settlement support voiding
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Exploring informal settlement fires in Indonesia: A study of fire risk assessment and fire resilient strategies in Medan
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作者 Aulia Malik Affif Alan March 《Resilient Cities and Structures》 2025年第4期1-20,共20页
The growth and scale of urbanisation in Indonesia poses various challenges,including the availability of affordable housing,which has forced many low-income people to live in informal settlements.Fires account for 15%... The growth and scale of urbanisation in Indonesia poses various challenges,including the availability of affordable housing,which has forced many low-income people to live in informal settlements.Fires account for 15%of all disasters in Indonesia,particularly in densely populated urban areas such as informal settlements.The nature of informal settlements,which lack basic services along with poor living conditions,increases the like-lihood of fire.The topic of informal settlement fires in Indonesia is relatively unresearched,especially studies tailored to waterfront informal settlements typologies which prevents an understanding of fire risk and its impact in the area.This study aims to investigate what aspects influence fire risk in the area and to increase the resilience of informal settlements to fire outbreaks with the intention of improving community resilience.A case study with mixed methods is employed in this study.Our study consists of two phases of data analysis.The first phase consists of spatial analysis,derivation of weight,risk assessment,sensitivity analysis,and identification of policy drivers.Meanwhile,the second phase of our data analysis consists of analysing conditions,challenges,and opportunities,resilient strategies development,and scenario testing.The results of this study revealed that the risk of fire in the area is considered high-to-very high,which is driven primarily by moderate hazard,high vulnerability,and low-to-very low capacity against fire.Primary drivers of fire risk in the area are building materials,electrical connection and equipment,road width,and building density.As a result,this study proposed nine physical and non-physical resilient strategies which has been categorised into three distinct aspects:development planning,development regulations,and risk management and response.Spatial analysis revealed that,if fully implemented and operationalised,these strategies could reclassify 90%of the area to moderate risk.Further research is should examine the causal factors of past fire incidents,the institutional capacity for fire management,and the socioeconomic conditions of the community. 展开更多
关键词 Informal settlements Fire risk reduction Fire safety RESILIENCE GIS-AHP
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Hydrologic Characteristics and Settlement Deformation of Backfilled Loess in Yan'an,China
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作者 Lina Ma Shengwen Qi Songfeng Guo 《Journal of Earth Science》 2025年第3期1198-1212,共15页
A gigantic project named Gully Land Consolidation(GLC)was launched in the hillgully region of the Chinese Loess Plateau in 2011 to cope with land degradation and create new farmlands for cultivation.The dynamic change... A gigantic project named Gully Land Consolidation(GLC)was launched in the hillgully region of the Chinese Loess Plateau in 2011 to cope with land degradation and create new farmlands for cultivation.The dynamic change of groundwater table and loess subsidence in the backfilled farmland are the main causes of site disasters and soil disease,but there is a lack of research on these issues.Based on this,the Shijiagou(SJG)backfilled farmland which is a typical GLC engineering site located in Ansai District,Yan'an City,Shaanxi Province was selected as the study area in this paper.Field site monitoring was carried out in this area,including four aspects of monitoring:rainfall,groundwater table,soil moisture and soil settlement displacement.The following findings were obtained from the analysis of the monitoring data in 2019-2020:(1)The backfilled farmlands have suffered a significant groundwater table rise.And the percentage increase of groundwater table increased from the upstream of F-1(such as 49.2%,46.3%,26.4%)to the downstream of F-5(90.0%,52.3%,34.2%correspondingly),which is related to the terrain of the valley channel and dam seepage.It is also revealed that rainfall characteristics are positively correlated with the depth of water infiltration and groundwater table.(2)The influence depth of rainfall infiltration on soil moisture of the backfilled loess in the GLC study area is no more than 2.5 m,and that within 1.5 m depth is significantly affected by rainfall.In addition,the dramatic rise in the groundwater table led to a steep increase in soil moisture,thus the soil underwent collapse deformation due to water immersion,and the farmland experienced large subsidence displacement.(3)The backfilled loess of the GLC farmland was in a continuous consolidation and settlement stage after the filling completion.With the passage of time,the settlement displacement and settlement rate of the backfilled loess gradually decreased,from 1.0-1.9 mm/d in 2019 to 0.4-0.8 mm/d in 2020,which indicates the GLC farmland tended to be stable.This study reveals the hydrological evolution characteristics and settlement deformation laws of the backfilled loess,which is important for the stability of the farmland and the management of the GLC project. 展开更多
关键词 backfilled loess gully land consolidation FARMLAND field monitoring GROUNDWATER soil moisture settlement displacement
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Sustainable communal septic tank systems in informal settlements:The case of Lebak Siliwangi,Indonesia
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作者 Kudakwashe Ncube 《Chinese Journal of Population,Resources and Environment》 2025年第1期121-131,共11页
This study focused on realizing Sustainable Development Goal(SDG)6 for inclusive clean water and sanitation;in particular Target 6.3,which aims to reduce untreated wastewater by 2030 while promoting circular wastewate... This study focused on realizing Sustainable Development Goal(SDG)6 for inclusive clean water and sanitation;in particular Target 6.3,which aims to reduce untreated wastewater by 2030 while promoting circular wastewater reuse and recycling globally.The main objective was to assess the adequacy and efficiency of communal septic tank systems in informal settlements while helping local planners and authorities in their decision-making regarding Target 6.3.Quantitative and qualitative approaches were employed with secondary data from previous researchers,and primary data were collected from field surveys,observations,and interviews with members of the local community.The research was delimited to two village administrative divisions known as Rukun Warga(Village Administrative Division,RW):RW 7 and RW 8 of Lebak Siliwangi Kampung in Coblong District,Bandung,West Java,Indonesia.The findings were also compared with situations in other informal settlements in Brazil,Bangladesh,and Nairobi.The results indicated the inadequacy of communal septic tanks in informal settlements due to factors such as substandard system design,limited support and communication between authorities and residents,and the gap between septic tank availability and capacity vis-a-vis demand.Other limiting factors included limited land availability and irregular geomorphology,the latter of which affected the siting and operation of septic tanks due a lack of room for upgrades or expansion in response to continuous population growth.These findings illustrate the need to complement communal septic systems with flexible centralized or decentralized systems to achieve Target 6.3 of SDG 6. 展开更多
关键词 Communal septic tank Informal settlement SUSTAINABILITY Sustainable development goals WASTEWATER
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Improving Shallow Foundation Settlement Prediction through Intelligent Optimization Techniques
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作者 Hadi Fattahi Hossein Ghaedi Danial Jahed Armaghani 《Computer Modeling in Engineering & Sciences》 2025年第4期747-766,共20页
In contemporary geotechnical projects,various approaches are employed for forecasting the settlement of shallow foundations(S_(m)).However,achieving precise modeling of foundation behavior using certain techniques(suc... In contemporary geotechnical projects,various approaches are employed for forecasting the settlement of shallow foundations(S_(m)).However,achieving precise modeling of foundation behavior using certain techniques(such as analytical,numerical,and regression)is challenging and sometimes unattainable.This is primarily due to the inherent nonlinearity of the model,the intricate nature of geotechnical materials,the complex interaction between soil and foundation,and the inherent uncertainty in soil parameters.Therefore,thesemethods often introduce assumptions and simplifications,resulting in relationships that deviate from the actual problem’s reality.In addition,many of these methods demand significant investments of time and resources but neglect to account for the uncertainty inherent in soil/rock parameters.This study explores the application of innovative intelligent techniques to predict S_(m) to address these shortcomings.Specifically,two optimization algorithms,namely teaching-learning-based optimization(TLBO)and harmony search(HS),are harnessed for this purpose.The modeling process involves utilizing input parameters,such as thewidth of the footing(B),the pressure exerted on the footing(q),the count of SPT(Standard Penetration Test)blows(N),the ratio of footing embedment(Df/B),and the footing’s geometry(L/B),during the training phase with a dataset comprising 151 data points.Then,the models’accuracy is assessed during the testing phase using statistical metrics,including the coefficient of determination(R^(2)),mean square error(MSE),and rootmean square error(RMSE),based on a dataset of 38 data points.The findings of this investigation underscore the substantial efficacy of intelligent optimization algorithms as valuable tools for geotechnical engineers when estimating S_(m).In addition,a sensitivity analysis of the input parameters in S_(m) estimation is conducted using@RISK software,revealing that among the various input parameters,the N exerts the most pronounced influence on S_(m). 展开更多
关键词 Shallow foundations optimization algorithms settlement prediction intelligent methods sensitivity analysis
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Probabilistic analysis of settlement characteristics induced by shield tunnelling in sandy cobble soil considering spatial variability
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作者 Fan WANG Pengfei LI +2 位作者 Xiuli DU Jianjun MA Lin WANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第8期771-786,共16页
Sandy cobble soil exhibits pronounced heterogeneity.The assessment of the uncertainty surrounding its properties is crucial for the analysis of settlement characteristics resulting from volume loss during shield tunne... Sandy cobble soil exhibits pronounced heterogeneity.The assessment of the uncertainty surrounding its properties is crucial for the analysis of settlement characteristics resulting from volume loss during shield tunnelling.In this study,a series of probabilistic analyses of surface and subsurface settlements was conducted considering the spatial variability of the friction angle and reference stiffness modulus,under different volumetric block proportions(Pv)and tunnel volume loss rates(ηt).The non-intrusive random finite difference method was used to investigate the probabilistic characteristics of maximum surface settlement,width of subsurface settlement trough,maximum subsurface settlement,and subsurface soil volume loss rate through Monte Carlo simulations.Additionally,a comparison between stochastic and deterministic analysis results is presented to underscore the significance of probabilistic analysis.Parametric analyses were subsequently conducted to investigate the impacts of the key input parameters in random fields on the settlement characteristics.The results indicate that scenarios with higher Pv or greaterηt result in a higher dispersion of stochastic analysis results.Neglecting the spatial variability of soil properties and relying solely on the mean values of material parameters for deterministic analysis may result in an underestimation of surface and subsurface settlements.From a probabilistic perspective,deterministic analysis alone may prove inadequate in accurately capturing the volumetric deformation mode of the soil above the tunnel crown,potentially affecting the prediction of subsurface settlement. 展开更多
关键词 Shield tunnels Sandy cobble soil settlement characteristics Spatial variability Probabilistic analysis
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A physics-constrained neural network for predicting excavationinduced ground surface settlement in clay
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作者 Yifeng Yang Shaoming Liao +3 位作者 Bak Koon Teoh Zewen Li Mengbo Liu Lisheng Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期2665-2681,共17页
Accurate prediction of ground surface settlement(GSS)adjacent to an excavation is important to prevent potential damage to the surrounding environment.Previous studies have extensively delved into this topic but all u... Accurate prediction of ground surface settlement(GSS)adjacent to an excavation is important to prevent potential damage to the surrounding environment.Previous studies have extensively delved into this topic but all under the limitations of either imprecise theories or insufficient data.In the present study,we proposed a physics-constrained neural network(PhyNN)for predicting excavation-induced GSS to fully integrate the theory of elasticity with observations and make full use of the strong fitting ability of neural networks(NNs).This model incorporates an analytical solution as an additional regularization term in the loss function to guide the training of NN.Moreover,we introduced three trainable parameters into the analytical solution so that it can be adaptively modified during the training process.The performance of the proposed PhyNN model is verified using data from a case study project.Results show that our PhyNN model achieves higher prediction accuracy,better generalization ability,and robustness than the purely data-driven NN model when confronted with data containing noise and outliers.Remarkably,by incorporating physical constraints,the admissible solution space of PhyNN is significantly narrowed,leading to a substantial reduction in the need for the amount of training data.The proposed PhyNN can be utilized as a general framework for integrating physical constraints into data-driven machine-learning models. 展开更多
关键词 Data-physics collaboratively driven EXCAVATION Ground surface settlement(GSS) Physics-constrained loss function Robustness Generalization ability
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Analysis of the Application of Contract Settlement Accounts for Insurance Companies Under the New Revenue Standard
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作者 Ji Shu'an Zhang Tiantian 《Journal of Humanities and Nature》 2025年第2期73-77,共5页
The implementation of the new revenue standard has a far-reaching impact on the accounting treatment of insurance enterprises,and the application of contract settlement accounts,as the key to connect business and fina... The implementation of the new revenue standard has a far-reaching impact on the accounting treatment of insurance enterprises,and the application of contract settlement accounts,as the key to connect business and financial accounting,needs to be standardized.This paper analyzes the core requirements of the new revenue standard,combines the special characteristics of insurance contracts with both service and financial attributes,and explains the logic of setting up and accounting methods of secondary accounts,such as insurance service income and investment component apportionment.In view of the practical pain points such as variable consideration apportionment and reclassification of inter-period contracts,the paper proposes strategies for system upgrading and internal control strengthening.The study shows that standardizing the application of accounts can help enterprises implement the requirements of the standard and improve the quality of financial information. 展开更多
关键词 New Revenue Standards Insurance Companies Contract settlement Accounts ACCOUNTING
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Mechanical behavior of train-slab track coupled system under subgrade settlement and earthquake excitation
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作者 LOU Ping SHI Tao YANG T.Y. 《Journal of Central South University》 2025年第11期4417-4438,共22页
Subgrade settlement is a common issue in soil ground within earthquake-prone regions,posing a threat to the safe operation of train-slab track coupled system(TSCS)in high-speed railways(HSRs).This study aims to analyz... Subgrade settlement is a common issue in soil ground within earthquake-prone regions,posing a threat to the safe operation of train-slab track coupled system(TSCS)in high-speed railways(HSRs).This study aims to analyze the mechanical behavior evolution of TSCS under subgrade settlement and earthquake excitation.The refined numerical model of slab track under subgrade differential settlement is established.The short settlement wavelength of 10 m causes the separation between the base and subgrade.The dynamic model of TSCS under subgrade settlement and earthquake excitation is developed.The dynamic response of TSCS exhibits more pronounced fluctuations under the combined effects of subgrade settlement and earthquake excitation than under the effects of settlement or earthquake alone.The evaluation indexes for the running safety of train on slab track under different settlement wavelengths exhibit varying degrees of increase with settlement amplitude and are particularly sensitive to the short settlement wavelength of 10 m.The wheel unloading rate and derailment coefficient of TSCS increase with earthquake intensity.Under the settlement wavelength of 10 m and amplitude of 20 mm,the wheel unloading rate of TSCS exceeds the allowable limit when the earthquake intensity exceeds 0.17g,and the derailment coefficient exceeds the allowable limit when the earthquake intensity surpasses 0.29g. 展开更多
关键词 train-slab track coupled system mechanical behavior subgrade differential settlement earthquake excitation running safety of train
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Gray relational analysis and SBOA-BP for predicting settlement intervals of high-speed railway subgrade
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作者 Quanpeng He Shaoyuan Li 《Railway Sciences》 2025年第2期199-212,共14页
Purpose–The deformation of the roadbed is easily influenced by the external environment to improve the accuracy of high-speed railway subgrade settlement prediction.Design/methodology/approach–A high-speed railway s... Purpose–The deformation of the roadbed is easily influenced by the external environment to improve the accuracy of high-speed railway subgrade settlement prediction.Design/methodology/approach–A high-speed railway subgrade settlement interval prediction method using the secretary bird optimization(SBOA)algorithm to optimize the BP neural network under the premise of gray relational analysis is proposed.Findings–Using the SBOA algorithm to optimize the BP neural network,the optimal weights and thresholds are obtained,and the best parameter prediction model is combined.The data were collected from the sensors deployed through the subgrade settlement monitoring system,and the gray relational analysis is used to verify that all four influencing factors had a great correlation to the subgrade settlement,and the collected data are verified using the model.Originality/value–The experimental results show that the SBOA-BP model has higher prediction accuracy than the BP model,and the SBOA-BP model has a wider range of prediction intervals for a given confidence level,which can provide higher guiding value for practical engineering applications. 展开更多
关键词 Gray relational analysis Secretary bird optimization algorithm Backpropagation neural network Subgrade settlement Interval prediction
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Real-time model updating and prediction of three-dimensional timevarying consolidation settlement using machine learning
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作者 Huaming Tian Yu Wang Danni Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第9期5954-5969,共16页
The development of digital twins for geotechnical structures necessitates the real-time updates of threedimensional(3D)virtual models(e.g.numerical finite element method(FEM)model)to accurately predict time-varying ge... The development of digital twins for geotechnical structures necessitates the real-time updates of threedimensional(3D)virtual models(e.g.numerical finite element method(FEM)model)to accurately predict time-varying geotechnical responses(e.g.consolidation settlement)in a 3D spatial domain.However,traditional 3D numerical model updating approaches are computationally prohibitive and therefore difficult to update the 3D responses in real time.To address these challenges,this study proposes a novel machine learning framework called sparse dictionary learning(T-3D-SDL)for real-time updating of time-varying 3D geotechnical responses.In T-3D-SDL,a concerned dataset(e.g.time-varying 3D settlement)is approximated as a linear superposition of dictionary atoms generated from 3D random FEM analyses.Field monitoring data are then used to identify non-trivial atoms and estimate their weights within a Bayesian framework for model updating and prediction.The proposed approach enables the real-time update of temporally varying settlements with a high 3D spatial resolution and quantified uncertainty as field monitoring data evolve.The proposed approach is illustrated using an embankment construction project.The results show that the proposed approach effectively improves settlement predictions along temporal and 3D spatial dimensions,with minimal latency(e.g.within minutes),as monitoring data appear.In addition,the proposed approach requires only a reasonably small number of 3D FEM model evaluations,avoids the use of widely adopted yet often criticized surrogate models,and effectively addresses the limitations(e.g.computational inefficiency)of existing 3D model updating approaches. 展开更多
关键词 Digital twin Three-dimensional(3D)finite element method(FEM) Time-varying 3D settlement Real-time model update Sparse dictionary learning(SDL)
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Evaluation of Human Settlement Quality of Nyingchi City,Southeastern Qinghai-Tibet Plateau,China
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作者 LIN Feng XIN Zhongbao +1 位作者 RAN Lishan QIAN Junxi 《Chinese Geographical Science》 2025年第6期1456-1472,共17页
The construction of human settlements plays a vital role in achieving sustainable development goals.With the growing population,both urban and rural planning—as well as the development of human settlements—on the Qi... The construction of human settlements plays a vital role in achieving sustainable development goals.With the growing population,both urban and rural planning—as well as the development of human settlements—on the Qinghai-Tibet Plateau in China have received increasing attention.This study proposed a comprehensive framework to assess the quality of human settlements and identify their limiting factors of Nyingchi City,southeastern Qinghai-Tibet Plateau of China.The framework integrated a region-specific evaluation system tailored to the plateau’s unique characteristics and utilized multi-source data collected through field-based questionnaires and remote sensing.Analytical methods employed include the Criteria Importance Through Intercriteria Correlation(CRITIC)weighting method,difference analysis for evaluating spatial and categorical variations,and a novel approach introduced in this study for identifying limiting factors.In August 2021,a questionnaire-based survey was conducted in the southeastern Qinghai-Tibet Plateau,yielding 823 valid responses.The average evaluation score for human settlement quality(HSQ)was(6.96±0.94),indicating that settlement conditions were approaching the satisfaction threshold.Notably,the score for the health dimension was(6.28±1.41),reflecting relatively underdeveloped health services in the region.From the perspective of spatial patterns,despite its favorable natural conditions,the HSQ in Medog County was relatively backward,reflecting uncoordinated development that warrants attention.Significant differences were observed in the perceptions of human settlements among different groups in terms of ethnicity,income,and educational background.Low ratings for income and employment conditions represented a major limitation to the local HSQ.The development of human settlements in the southeastern Qinghai-Tibet Plateau still needs further promotion due to population disparities and the challenges of creating a healthy environment in high-altitude regions.The results are valuable for improving human settlements in plateau regions,which can help make targeted policy recommendations. 展开更多
关键词 human settlement quality(HSQ) questionnaire survey criteria importance through intercriteria correlation(CRITIC)weight method multisource data evaluation Nyingchi City Qinghai-Tibet Plateau China
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路基不均匀沉降引起的轨道损伤变形及其对车轨动力响应的影响分析
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作者 李国芳 张向钰 +4 位作者 高全福 马理超 吴少培 李得洋 李宏洲 《振动工程学报》 北大核心 2026年第2期434-444,共11页
为探究路基沉降区段无砟轨道损伤变形对行车安全性和轨道服役性能的影响规律,基于有限元方法和混凝土塑性损伤本构理论,建立考虑结构配筋及轨道结构层间粘接关系的CRTSⅡ型板式无砟轨道精细化非线性分析模型,研究沉降位置、波长、幅值... 为探究路基沉降区段无砟轨道损伤变形对行车安全性和轨道服役性能的影响规律,基于有限元方法和混凝土塑性损伤本构理论,建立考虑结构配筋及轨道结构层间粘接关系的CRTSⅡ型板式无砟轨道精细化非线性分析模型,研究沉降位置、波长、幅值对轨道结构变形损伤的影响规律;基于有限元-多体系统动力学方法(FE-MBD),建立高速车辆-轨道-路基耦合系统动力学模型,分析不均匀沉降下高速铁路车-线-路基耦合系统动力响应。结果表明:当沉降位置发生在宽窄接缝处时,钢轨位移最大,且轨道板最先产生宏观裂纹;车体垂向加速度与轮轨垂向力对沉降幅值敏感,随沉降幅值的增大明显增加;轮轨垂向力及轨道结构的振动响应随沉降波长的增加均呈现先增大后减小的趋势,当沉降波长≤15m时,路基沉降对车轨系统动力响应的不利影响尤为显著,应予以重视。研究结论可为路基沉降区高速铁路运营及线路不均匀沉降病害防治提供参考。 展开更多
关键词 高速铁路 无砟轨道 塑性损伤 内聚力模型 沉降变形 轮轨关系 耦合振动
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地铁不同类型轨道对基础变形的适应能力研究
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作者 曾志平 齐星哲 +3 位作者 李沛成 郭骁 田春雨 吴达 《中南大学学报(自然科学版)》 北大核心 2026年第1期195-206,共12页
地铁隧道的不均匀沉降会显著影响轨道结构的力学性能及运营安全。为研究在基础不均匀沉降变形作用下地铁不同类型轨道的变形特性以及其对基础不均匀沉降变形的适应能力,本文以我国地铁常用的4种轨道结构(即普通整体道床轨道、减振扣件... 地铁隧道的不均匀沉降会显著影响轨道结构的力学性能及运营安全。为研究在基础不均匀沉降变形作用下地铁不同类型轨道的变形特性以及其对基础不均匀沉降变形的适应能力,本文以我国地铁常用的4种轨道结构(即普通整体道床轨道、减振扣件式整体道床轨道、钢弹簧浮置板轨道和减振垫浮置板轨道)为研究对象,基于有限元法建立余弦型不均匀沉降条件下轨道系统空间分析模型,系统研究不同轨道类型对基础不均匀沉降变形的适应能力及其变形特性。研究表明:1) 4种轨道结构在基础沉降下的钢轨与道床变形曲线高度一致,沉降中心处变形最大,沉降波起止端存在局部上拱现象;2)普通整体道床轨道和减振扣件式整体道床轨道因纵向刚度较大,在沉降幅值大于20 mm和沉降波长小于10 m的条件下易发生非线性变形或上拱现象,对基础变形的适应能力较弱;相比之下,钢弹簧浮置板轨道和减振垫浮置板轨道因结构具有柔性特点,对基础变形的适应能力较强;3)钢弹簧浮置板轨道和减振垫浮置板轨道的轨道板顶面沉降值可用于判断基础沉降幅值,而对于普通整体道床轨道和减振扣件式整体道床轨道,仅能观测到道床顶面沉降值,难以准确判断沉降幅值。研究结果可为地铁轨道结构设计优化及基础变形作用下的轨道系统运营维护提供理论依据与工程参考。 展开更多
关键词 地铁 基础沉降 无砟轨道 浮置板轨道 有限元
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沿海型沉积岛人居景观演变特征研究——以广东南三岛为例
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作者 潘莹 吴亦可 施瑛 《南方建筑》 北大核心 2026年第2期10-20,共11页
沉积岛按分布位置可分为河口型和沿海型,两者开发方式存在差异,研究沿海型沉积岛的人居景观演变和岛内人地互动模式,对营建良好的海岛人居环境和实现海岛可持续发展有重要意义。以广东南三岛为样本,结合GIS软件,从历时性角度明确了南三... 沉积岛按分布位置可分为河口型和沿海型,两者开发方式存在差异,研究沿海型沉积岛的人居景观演变和岛内人地互动模式,对营建良好的海岛人居环境和实现海岛可持续发展有重要意义。以广东南三岛为样本,结合GIS软件,从历时性角度明确了南三岛人居景观演化的五大阶段,采用三生理论解析宏观尺度南三岛人居景观斑块的演变特征,以类型划分的方法分析中观尺度岛内聚落的演化差异,并引用“压力-状态-响应”理论解析了沿海型沉积岛“与人为活动联系紧密,自然环境响应快速”的人地互动共性,以期为此类岛屿的未来发展策略研究提供参考。 展开更多
关键词 景观演变 海岛人居景观 沉积岛 南三岛 人地关系
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