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Experimental and theoretical study of the smoke back-layering length in a tunnel with cross-passage:effects of longitudinal fire source locations
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作者 Zhisheng Li Yuchun Zhang +2 位作者 Maozhen Qiao Yunji Gao Yule Huang 《Railway Engineering Science》 2026年第1期184-199,共16页
The diversion effect caused by the linked structure in a metro tunnel with cross-passage complicates the impact of longitudinal fire source location on the smoke backflow layering behavior that has not been clarified,... The diversion effect caused by the linked structure in a metro tunnel with cross-passage complicates the impact of longitudinal fire source location on the smoke backflow layering behavior that has not been clarified,despite the fact that the scenario exists in practice.A series of laboratory-scale experiments were conducted in this study to investigate the smoke back-layering length in a model tunnel with cross-passage.The heat release rate,the velocity of longitudinal air flow,and the location of the fire source were all varied.It was found that the behavior of smoke backflow for the fire source located at the upstream of bifurcation point resembles a single-hole tunnel fire.As the fire source’s position shifts downstream from the bifurcation point,the length of smoke back-layering progressively increases.A competitive interaction exists between airflow diversion and smoke diversion during smoke backflow,significantly affecting the smoke back-layering length in the main tunnel.The dimensionless smoke back-layering length model was formulated in a tunnel featuring a cross-passage,taking into account the positions of longitudinal fire sources.The dimensionless smoke back-layering length exhibits a positive correlation with the 17/18 power of total heat release rate Q and a negative correlation with the 5/2 power of longitudinal ventilation velocity V. 展开更多
关键词 Tunnel fire Cross-passage Smoke back-layering length Fire source location Longitudinal ventilation
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基于Delaunay三角网与核哈希表的空间co-location核模式挖掘
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作者 张琪 芦俊丽 +2 位作者 段鹏 罗浩瑜 唐明香 《云南民族大学学报(自然科学版)》 2026年第1期117-128,154,共13页
空间co-location模式挖掘用于揭示地理空间数据中实体间关联关系,广泛应用于城市规划和环境监测等领域.然而,传统方法在处理大规模或复杂空间数据时,通常依赖人为设定的距离阈值,存在计算效率与准确度局限.为此,提出了一种基于Delaunay... 空间co-location模式挖掘用于揭示地理空间数据中实体间关联关系,广泛应用于城市规划和环境监测等领域.然而,传统方法在处理大规模或复杂空间数据时,通常依赖人为设定的距离阈值,存在计算效率与准确度局限.为此,提出了一种基于Delaunay三角网和核哈希表的空间co-location核模式挖掘方法.该方法利用Delaunay三角剖分优化空间数据的邻近关系,避免人为设定阈值的问题,并构建Delaunay邻域物化模型(DNM)减少尖锐三角形,以提升空间数据的组织效率.同时,结合核哈希表实现高效存储和检索,提出HKP算法,提高核模式挖掘的计算效率.实验结果表明,与现有优秀算法CPM、DTC和Join-less相比,HKP算法在准确性和扩展性上均具有显著优势,适用于大规模空间数据挖掘应用. 展开更多
关键词 空间co-location核模式 DELAUNAY三角网 核哈希表 HKP DNM
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A high-precision heuristic model to detect home and work locations from smart card data 被引量:4
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作者 Nilufer Sari Aslam Tao Cheng James Cheshire 《Geo-Spatial Information Science》 SCIE CSCD 2019年第1期1-11,共11页
Smart card-automated fare collection systems now routinely record large volumes of data comprising the origins and destinations of travelers.Processing and analyzing these data open new opportunities in urban modeling... Smart card-automated fare collection systems now routinely record large volumes of data comprising the origins and destinations of travelers.Processing and analyzing these data open new opportunities in urban modeling and travel behavior research.This study seeks to develop an accurate framework for the study of urban mobility from smart card data by developing a heuristic primary location model to identify the home and work locations.The model uses journey counts as an indicator of usage regularity,visit-frequency to identify activity locations for regular commuters,and stay-time for the classification of work and home locations and activities.London is taken as a case study,and the model results were validated against survey data from the London Travel Demand Survey and volunteer survey.Results demonstrate that the proposed model is able to detect meaningful home and work places with high precision.This study offers a new and cost-effective approach to travel behavior and demand research. 展开更多
关键词 Smart card data activity location modeling heuristic primary location model home and work locations human mobility pattern urban activity pattern
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基于混合t-t Location-scale分布的风电功率波动特性研究
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作者 徐凯 熊国江 《电气工程学报》 北大核心 2026年第1期412-422,共11页
风电功率波动的随机性和不确定性是限制风能消纳的主要原因之一,风电功率的波动会影响风电功率的准确预测。定量描述风电功率的波动特性成为解决这些问题的关键。从风电功率波动“尖峰厚尾”的特征出发,将t分布与t Location-scale分布... 风电功率波动的随机性和不确定性是限制风能消纳的主要原因之一,风电功率的波动会影响风电功率的准确预测。定量描述风电功率的波动特性成为解决这些问题的关键。从风电功率波动“尖峰厚尾”的特征出发,将t分布与t Location-scale分布两者的优势结合,提出混合t-t Location-scale分布。为了避免以往方法参数估计精度不足的问题,引入一种智能优化算法——正余弦优化算法,来进行分布模型的参数估计。将所提模型与正态分布、混合t Location-scale分布等5种模型进行对比,并从15 min、30 min和45 min 3个滑动平均时段长度验证了模型的适用性。通过我国西北地区3个风电场的历史数据进行仿真试验,对比3个评价指标,发现所提模型对风电功率波动具有很好的拟合性能。 展开更多
关键词 混合t-t location-scale分布 风电功率波动 正余弦优化算法 滑动平均法 时间尺度
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Nomenclature and location of acupuncture points for laboratory animals Part 3:Mouse 被引量:3
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作者 《World Journal of Acupuncture-Moxibustion》 2025年第2期160-162,共3页
This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 3:Mouse.This standard was released by the China Associ... This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 3:Mouse.This standard was released by the China Association of Acupuncture and Moxibustion on May 15,2020,implemented on October 31,2020,and published by Standards Press of China.The standard was drafted by the Institute of Acupuncture and Moxibustion,China Academy of Chinese Medical Sciences,and the Nanjing University of Chinese Medicine.Principal draftsmen:Xiang-hong JING and Xing-bang HUA.Participating draftsmen:Wan-zhu BAI,Bin XU,Dong-sheng XU,Yi GUO,Tie-ming MA,Xin-jun WANG,and Sheng-feng LU. 展开更多
关键词 acupuncture points STANDARD MOUSE NOMENCLATURE location acupuncture points association standardt caam location acupuncture moxibustion
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Nomenclature and location of acupuncture points for laboratory animals Part 2 被引量:2
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作者 《World Journal of Acupuncture-Moxibustion》 2025年第2期163-165,共3页
This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 2:Rat.This standard was released by the China Associat... This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 2:Rat.This standard was released by the China Association of Acupuncture and Moxibustion on May 15,2020,implemented on October 31,2020,and published by Standards Press of China.The standard was drafted by the Institute of Acupuncture and Moxibustion,China Academy of Chinese Medical Sciences,and the Nanjing University of Chinese Medicine.Principal draftsmen:Xiang-hong JING and Xing-bang HUA.Participating draftsmen:Wan-Zhu BAI,Bin XU,Dong-sheng XU,Yi GUO,Tie-ming MA,Xin-jun WANG,and Sheng-feng LU. 展开更多
关键词 acupuncture points STANDARD NOMENCLATURE rat association standardt caam location acupuncture moxibustion
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Pan-immune-inflammation in colon cancer:A prognostic biomarker and the role of tumor location in personalized care 被引量:1
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作者 Gaya Spolverato Giulia Capelli +2 位作者 Floriane Noel Michele Steindler Andrew Alexander Gumbs 《World Journal of Gastrointestinal Surgery》 2025年第4期1-6,共6页
Despite advances in surgery,chemotherapy,and radiotherapy,the treatment of colorectal cancer(CRC)requires more personalized approaches based on tumor biology and molecular profiling.While some relevant mutations have ... Despite advances in surgery,chemotherapy,and radiotherapy,the treatment of colorectal cancer(CRC)requires more personalized approaches based on tumor biology and molecular profiling.While some relevant mutations have been associated with differential response to immunotherapy,such as RAS and BRAF mutations limiting response to anti-epithelial growth factor receptor drugs or microsatellite instability predisposing susceptibility to immune checkpoint inhibitors,the role of inflammation in dictating tumor progression and treatment response is still under investigation.Several inflammatory biomarkers have been identified to guide patient prognosis.These include the neutrophil-lymphocyte ratio,Glasgow prognostic score(GPS)and its modified version,lymphocyte-Creactive protein ratio,and platelet-lymphocyte ratio.However,these markers are not yet included in the standard clinical management of patients with CRC,and further research is needed to evaluate their efficacy in different patient populations.A recent study by Wang et al,published in the World Journal of Gastroenterology,sheds light on the prognostic significance of pan-immune-inflammation value(PIV)in CRC,particularly concerning primary tumor location.Specifically,the authors found that a high PIV was strongly correlated with worse disease-free survival in patients with left-sided colon cancer,whereas no such association was observed in patients with right-sided colon cancer.Integrating tumor location into the prognostic assessment of CRC may improve our ability to more accurately identify high-risk patients and develop personalized treatment plans that are more likely to improve patient outcomes. 展开更多
关键词 Colorectal cancer Inflammatory biomarkers Tumor location Targeted therapy
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A new predictive based secure geographic routing strategy for UAV network under location spoofing attack
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作者 Zihao ZHOU Jie TANG +3 位作者 Zhutian YANG Junyuan FAN Xiaokai SONG Kai Kit WONG 《Chinese Journal of Aeronautics》 2025年第10期47-58,共12页
Unmanned aerial vehicle(UAV)swarm network consisting of a collection of micro UAVs can be used for many applications.It is well established that packet routing is a fundamental problem to achieve UAV collaboration.How... Unmanned aerial vehicle(UAV)swarm network consisting of a collection of micro UAVs can be used for many applications.It is well established that packet routing is a fundamental problem to achieve UAV collaboration.However,the highly dynamic nature of UAVs,frequently changing network topologies and security issues,poses significant challenges to packet forwarding in UAV networks.The existing topology-based routing protocols are not well suited in UAV network due to their high controlling overhead or excessive end-to-end delay.Geographic routing is regarded as a promising solution,as it only requires local information.In order to enhance the accuracy and security of geographic routing in highly dynamic UAV network,in this paper,we propose a new predictive geographic(PGeo)routing strategy with location verification.First,a detection mechanism is adopted to recognize malicious UAVs falsifying their location.Then,an accurate average service time of a packet in the medium access control(MAC)layer is derived to assist location prediction.The proposed delay model can provide a theoretical basis for future work,and our simulation results reveal that PGeo outstrips the existing geographic routing protocols in terms of packet delivery ratio in the presence of location spoofing behavior. 展开更多
关键词 Unmanned aerial vehicle Secure communication Geographic routing location spoofing Delay estimation location prediction location verification
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Recent progress on high-precision construction of nanoarchitectured SERS substrates for ultrasensitive bio-medical sensors
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作者 Heguang Liu Ben Mou +8 位作者 Jinxin Li Na Tian Yiming Feng Xiaodong Cui Yury Kapitonov Huageng Liang Caiyin You Yuan Li Tianyou Zhai 《Advanced Powder Materials》 2025年第4期30-57,共28页
Surface-enhanced Raman spectroscopy(SERS)has evolved from a laboratory technique to a practical tool for ultra-sensitive detection,particularly in the biomedical field,where precise molecular identification is crucial... Surface-enhanced Raman spectroscopy(SERS)has evolved from a laboratory technique to a practical tool for ultra-sensitive detection,particularly in the biomedical field,where precise molecular identification is crucial.Despite significant advancements,a gap remains in the literature,as no comprehensive review systematically addresses the high-precision construction of SERS substrates for ultrasensitive biomedical detection.This review fills that gap by exploring recent progress in fabricating high-precision SERS substrates,emphasizing their role in enabling ultrasensitive bio-medical sensors.We carefully examine the key to these advancements is the precision engineering of substrates,including noble metals,semiconductors,carbon-based materials,and two-dimensional materials,which is essential for achieving the high sensitivity required for ultrasensitive detection.Applications in biomedical diagnostics and molecular analysis are highlighted.Finally,we address the challenges in SERS substrate preparation and outline future directions,focusing on improvement strategies,design concepts,and expanding applications for these advanced materials. 展开更多
关键词 SERS SERS substrates high-precision construction Ultrasensitive bio-medical sensors Enhancement mechanism
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High-precision large-aperture single-frame interferometric surface profile measurement method based on deep learning
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作者 Liang Tang Mingzhi Han +3 位作者 Shuai Yang Ye Sun Lirong Qiu Weiqian Zhao 《International Journal of Extreme Manufacturing》 2025年第5期481-492,共12页
Large-aperture optical components are of paramount importance in domains such as integrated circuits,photolithography,aerospace,and inertial confinement fusion.However,measuring their surface profiles relies predomina... Large-aperture optical components are of paramount importance in domains such as integrated circuits,photolithography,aerospace,and inertial confinement fusion.However,measuring their surface profiles relies predominantly on the phase-shifting approach,which involves collecting multiple interferograms and imposes stringent demands on environmental stability.These issues significantly hinder its ability to achieve real-time and dynamic high-precision measurements.Therefore,this study proposes a high-precision large-aperture single-frame interferometric surface profile measurement(LA-SFISPM)method based on deep learning and explores its capability to realize dynamic measurements with high accuracy.The interferogram is matched to the phase by training the data measured using the small aperture.The consistency of the surface features of the small and large apertures is enhanced via contrast learning and feature-distribution alignment.Hence,high-precision phase reconstruction of large-aperture optical components can be achieved without using a phase shifter.The experimental results show that for the tested mirror withΦ=820 mm,the surface profile obtained from LA-SFISPM is subtracted point-by-point from the ground truth,resulting in a maximum single-point error of 4.56 nm.Meanwhile,the peak-to-valley(PV)value is 0.0758λ,and the simple repeatability of root mean square(SR-RMS)value is 0.00025λ,which aligns well with the measured results obtained by ZYGO.In particular,a significant reduction in the measurement time(reduced by a factor of 48)is achieved compared with that of the traditional phase-shifting method.Our proposed method provides an efficient,rapid,and accurate method for obtaining the surface profiles of optical components with different diameters without employing a phase-shifting approach,which is highly desired in large-aperture interferometric measurement systems. 展开更多
关键词 large-aperture optical components single-frame interferometric surface profile deep learning dynamic high-precision measurement
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Precise Location of Passive Intermodulation in Long Cables by Fractional Frequency Based Multi-Range Rulers
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作者 DONG Anhua LIANG Haodong +2 位作者 ZHU Shaohao ZHANG Qi ZHAO Deshuang 《ZTE Communications》 2025年第1期101-106,共6页
A novel method is developed by utilizing the fractional frequency based multirange rulers to precisely position the passive inter-modulation(PIM)sources within radio frequency(RF)cables.The proposed method employs a s... A novel method is developed by utilizing the fractional frequency based multirange rulers to precisely position the passive inter-modulation(PIM)sources within radio frequency(RF)cables.The proposed method employs a set of fractional frequencies to create multiple measuring rulers with different metric ranges to determine the values of the tens,ones,tenths,and hundredths digits of the distance.Among these rulers,the one with the lowest frequency determines the maximum metric range,while the one with the highest frequency decides the highest achievable accuracy of the position system.For all rulers,the metric accuracy is uniquely determined by the phase accuracy of the detected PIM signals.With the all-phase Fourier transform method,the phases of the PIM signals at all fractional frequencies maintain almost the same accuracy,approximately 1°(about 1/360 wavelength in the positioning accuracy)at the signal-to-noise ratio(SNR)of 10 d B.Numerical simulations verify the effectiveness of the proposed method,improving the positioning accuracy of the cable PIM up to a millimeter level with the highest fractional frequency operating at 200 MHz. 展开更多
关键词 passive intermodulation location multi-range
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An efficient and high-precision algorithm for solving multiple deformation modes of elastic beams
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作者 Yunzhou WANG Binbin ZHENG +2 位作者 Lingling HU Nan SUN Minghui FU 《Applied Mathematics and Mechanics(English Edition)》 2025年第9期1753-1770,共18页
The elliptic integral method(EIM) is an efficient analytical approach for analyzing large deformations of elastic beams. However, it faces the following challenges.First, the existing EIM can only handle cases with kn... The elliptic integral method(EIM) is an efficient analytical approach for analyzing large deformations of elastic beams. However, it faces the following challenges.First, the existing EIM can only handle cases with known deformation modes. Second,the existing EIM is only applicable to Euler beams, and there is no EIM available for higher-precision Timoshenko and Reissner beams in cases where both force and moment are applied at the end. This paper proposes a general EIM for Reissner beams under arbitrary boundary conditions. On this basis, an analytical equation for determining the sign of the elliptic integral is provided. Based on the equation, we discover a class of elliptic integral piecewise points that are distinct from inflection points. More importantly, we propose an algorithm that automatically calculates the number of inflection points and other piecewise points during the nonlinear solution process, which is crucial for beams with unknown or changing deformation modes. 展开更多
关键词 elastic beam elliptic integral deformation mode transition equilibrium path high-precision algorithm
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Automatic location of surface-monitored microseismicity with deep learning
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作者 Zhaolong Gan Xiao Tian +1 位作者 Xiong Zhang Mengxue Dai 《Earthquake Research Advances》 2025年第2期20-31,共12页
Accurate and rapid determination of source locations is of great significance for surface microseismic monitoring.Traditional methods,such as diffraction stacking,are time-consuming and challenging for real-time monit... Accurate and rapid determination of source locations is of great significance for surface microseismic monitoring.Traditional methods,such as diffraction stacking,are time-consuming and challenging for real-time monitoring.In this study,we propose an approach to locate microseismic events using a deep learning algorithm with surface data.A fully convolutional network is designed to predict source locations.The input data is the waveform of a microseismic event,and the output consists of three 1D Gaussian distributions representing the probability distribution of the source location in the x,y,and z dimensions.The theoretical dataset is generated to train the model,and several data augmentation methods are applied to reduce discrepancies between the theoretical and field data.After applying the trained model to field data,the results demonstrate that our method is fast and achieves comparable location accuracy to the traditional diffraction stacking location method,making it promising for real-time microseismic monitoring. 展开更多
关键词 Microseismic monitoring Source location Deep learning
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Research on Integrated Circuit Talent Stability Construction Based on Turnover Attribution in High-Precision, Specialized, and Innovative Enterprises
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作者 Mingjie Cheng Ziying Chen +1 位作者 Xiayuan Huang Zhixin Jian 《Proceedings of Business and Economic Studies》 2025年第5期87-94,共8页
With the intensifying competition in the integrated circuit(IC)industry,the high turnover rate of integrated circuit engineers has become a prominent issue affecting the technological continuity of high-precision,spec... With the intensifying competition in the integrated circuit(IC)industry,the high turnover rate of integrated circuit engineers has become a prominent issue affecting the technological continuity of high-precision,specialized,and innovative enterprises.As a representative of such enterprises,JL Technology has faced challenges to its R&D efficiency due to talent loss in recent years.This study takes this enterprise as a case to explore feasible paths to reduce turnover rates through optimizing training and career development systems.The research designs a method combining learning maps and talent maps,utilizes a competency model to clarify the direction for engineers’skill improvement,implements talent classification management using a nine-grid model,and achieves personalized training through Individual Development Plans(IDPs).Analysis of the enterprise’s historical data reveals that the main reasons for turnover are unclear career development paths and insufficient resources for skill improvement.After pilot implementation,the turnover rate in core departments decreased by 12%,and employee satisfaction with training increased by 24%.The results indicate that matching systematic talent reviews with dynamic learning resources can effectively enhance engineers’sense of belonging.This study provides a set of highly operational management tools for small and medium-sized high-precision,specialized,and innovative technology enterprises,verifies their applicability in such enterprises,and offers replicable experiences for similar enterprises to optimize their talent strategies[1]. 展开更多
关键词 high-precision specialized and innovative enterprises IC engineers Learning map Talent review Talent map
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Dynamic geographies and locational factors of techno-environmentally heterogeneous data centers in Chinese cities,2006-2021
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作者 XU Jili LIU Xiangjie +1 位作者 HUANG Guan YE Yuyao 《Journal of Geographical Sciences》 2025年第9期1845-1862,共18页
Data centers operate as physical digital infrastructure for generating,storing,computing,transmitting,and utilizing massive data and information,constituting the backbone of the flourishing digital economy across the ... Data centers operate as physical digital infrastructure for generating,storing,computing,transmitting,and utilizing massive data and information,constituting the backbone of the flourishing digital economy across the world.Given the lack of a consistent analysis for studying the locational factors of data centers and empirical deficiencies in longitudinal investigations on spatial dynamics of heterogeneous data centers,this paper develops a comprehensive analytical framework to examine the dynamic geographies and locational factors of techno-environmentally heterogeneous data centers across Chinese cities in the period of 2006–2021.First,we develop a“supply-demand-environment trinity”analytical framework as well as an accompanying evaluation indicator system with Chinese characteristics.Second,the dynamic geographies of data centers in Chinese cities over the last decades are characterized as spatial polarization in economically leading urban agglomerations alongside persistent interregional gaps across eastern,central,and western regions.Data centers present dual spatial expansion trajectories featuring outward radiation from eastern core urban agglomerations to adjacent peripheries and leapfrog diffusion to strategic central and western digital infrastructural hubs.Third,it is empirically verified that data center construction in Chinese cities over the last decades has been jointly influenced by supply-,demand-,and environment-side locational factors,echoing the efficacy of the trinity analytical framework.Overall,our findings demonstrate the temporal variance,contextual contingency,and attribute-based differentiation of locational factors underlying techno-environmentally heterogeneous data centers in Chinese cities. 展开更多
关键词 data center digital infrastructure digital economy locational factor China
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Microseismic source location based on multi-sensor arrays and particle swarm optimization algorithm
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作者 LIU Ling-hao SHANG Xue-yi +2 位作者 WANG Yi LI Xi-bing FENG Fan 《Journal of Central South University》 2025年第9期3297-3313,共17页
Microseismic (MS) source location plays an important role in MS monitoring. This paper proposes a MS source location method based on particle swarm optimization (PSO) and multi-sensor arrays, where a free weight joint... Microseismic (MS) source location plays an important role in MS monitoring. This paper proposes a MS source location method based on particle swarm optimization (PSO) and multi-sensor arrays, where a free weight joints the P-wave first arrival data. This method adaptively adjusts the preference for “superior” arrays and leverages “inferior” arrays to escape local optima, thereby improving the location accuracy. The effectiveness and stability of this method were validated through synthetic tests, pencil-lead break (PLB) experiments, and mining engineering applications. Specifically, for synthetic tests with 1 μs Gaussian noise and 100 μs large noise in rock samples, the location error of the multi-sensor arrays jointed location method is only 0.30 cm, which improves location accuracy by 97.51% compared to that using a single sensor array. The average location error of PLB events on three surfaces of a rock sample is reduced by 48.95%, 26.40%, and 55.84%, respectively. For mine blast event tests, the average location error of the dual sensor arrays jointed method is 62.74 m, 54.32% and 14.29% lower than that using only sensor arrays 1 and 2, respectively. In summary, the proposed multi-sensor arrays jointed location method demonstrates good noise resistance, stability, and accuracy, providing a compelling new solution for MS location in relevant mining scenarios. 展开更多
关键词 microseismic monitoring source location particle swarm optimization multi-sensor arrays
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Analysis of factors infl uencing microseismic detection and location in shale gas extraction areas of western Hubei
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作者 Hao Wan-peng Zhang Li-fen +3 位作者 Zhao Yan-nan Zheng Rong-ying Qin Wei-bing and Li Jing-gang 《Applied Geophysics》 2025年第2期523-534,561,共13页
The study area is rich in shale gas resources and has reached the stage of comprehensive development. Shale gas extraction poses risks such as induced seismicity and well closure, compounded by the limited availabilit... The study area is rich in shale gas resources and has reached the stage of comprehensive development. Shale gas extraction poses risks such as induced seismicity and well closure, compounded by the limited availability of fi xed seismic monitoring stations nearby. To address these challenges, a dense observation array was developed within the study area to monitor and analyze microseismic activity during hydraulic fracturing. Microseismic events generated by hydraulic fracturing typically exhibit low amplitude and signal-to-noise ratio, rendering traditional manual analysis methods impractical. To overcome these limitations, an innovative artifi cial intelligence method combining picking-association-location (PAL) and match-expand- shift-stack (MESS) techniques (PALM) has been utilized for automated seismic detection. Numerous factors influence the accuracy of microseismic detection and localization. To evaluate these factors, the effects of various velocity structure models, instrument types, and station distributions on seismic location were analyzed and compared. The results indicate that the PALM method significantly mitigates the influence of velocity structure models on seismic location accuracy. Additionally, the use of broadband seismic instruments and a uniform station distribution enhances the precision of seismic location results. Furthermore, by integrating data from diff erent types of observation instruments, a comprehensive seismic catalog for the study area was established. These fi ndings not only enhance seismic location accuracy but also provide valuable guidance for optimizing regional seismic monitoring network design and improving seismic risk assessment. 展开更多
关键词 earthquake location velocity structure model station distribution PALM shale gas
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Travel-time corrections for stations in the Guangdong seismic network and their impact on earthquake location accuracy
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作者 Ming Liang Xuan Yang +3 位作者 Ce Jiang Ping Tian Qingxi Lin Xijiao Jiang 《Earthquake Research Advances》 2025年第3期56-67,共12页
The travel-time corrections for the primary seismic phases of 72 stations in the Guangdong seismic network,relative to the 1D South China travel-time model,were determined using joint hypocentral determination(JHD)and... The travel-time corrections for the primary seismic phases of 72 stations in the Guangdong seismic network,relative to the 1D South China travel-time model,were determined using joint hypocentral determination(JHD)and statistical analysis methods.The travel-time corrections for the Pg phase of 72 stations range between-0.25 s and 0.14 s,while the corrections for the Sg phase range between 0.27 s and 0.35 s,and those for the Pn phase are between-0.86 s and 0.07 s.The spatial distribution of travel-time corrections for Pg,Sg,and Pn phases of 72 stations correlates well with the geological structure in this region.This indicates that the travel-time corrections for Pg and Sg phases are mainly caused by the discrepancy between the actual crustal velocity structure beneath the stations and the 1D South China travel-time model.These corrections empirically compensate for systematic travel-time errors arising from such discrepancies.The primary factor contributing to the travel-time corrections for the Pn phase is the Moho undulations or tilt.These corrections are intended to compensate for systematic errors in travel time caused by variations in the actual Moho.By integrating the obtained travel-time corrections into the HYPO-SAT location algorithm,test results showed an obvious improvement in location accuracy and origin time precision for explosion events.The variation of horizontal distance between repeating earthquake pairs has also improved,with 86%of the repeating earthquake pair spacing being more accurately estimated after correction.This suggests the crucial significance of travel-time correction in earthquake location,and the consideration of travel-time correction exerts a notable impact on enhancing earthquake location accuracy. 展开更多
关键词 Travel-time correction Joint hypocentral determination Statistical analysis Hyposat location accuracy
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Performance evaluation of the waveform stacking-based microseismic location method in the southern Sichuan Basin of China
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作者 Lei Li Jiacheng Zhang +4 位作者 Yuyang Tan Ling Peng Junlun Li Jincheng Xu Jianxin Liu 《Earthquake Science》 2025年第5期427-440,共14页
Seismic source locations can characterize the spatial and temporal distributions of seismic sources,and can provide important basic data for earthquake disaster monitoring,fault activity characterization,and fracture ... Seismic source locations can characterize the spatial and temporal distributions of seismic sources,and can provide important basic data for earthquake disaster monitoring,fault activity characterization,and fracture growth interpretation.Waveform stacking-based location methods invert the source locations by focusing the source energy with multichannel waveforms,and these methods exhibit a high level of automation and noise-resistance.Taking the cross-correlation stacking(CCS)method as an example,this work attempts to study the influential factors of waveform stacking-based methods,and introduces a comprehensive performance evaluation scheme based on multiple parameters and indicators.The waveform data are from field monitoring of induced microseismicity in the Changning region(southern Sichuan Basin of China).Synthetic and field data tests reveal the impacts of three categories of factors on waveform stacking-based location:velocity model,monitoring array,and waveform complexity.The location performance is evaluated and further improved in terms of the source imaging resolution and location error.Denser array monitoring contributes to better constraining source depth and location reliability,but the combined impact of multiple factors,such as velocity model uncertainty and multiple seismic phases,increases the complexity of locating field microseismic events.Finally,the aspects of location uncertainty,phase detection,and artificial intelligencebased location are discussed. 展开更多
关键词 seismic location waveform stacking induced microseismicity performance evaluation cross-correlation stacking
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Architectural heritage as filming location:impact on identity and significance
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作者 Tejashree Lakras 《Built Heritage》 2025年第3期44-59,共16页
Using architectural heritage sites as filming locations has unintended and diverse effects on the sites and their relationships with stakeholders.While this phenomenon has attracted scholars largely from the heritage ... Using architectural heritage sites as filming locations has unintended and diverse effects on the sites and their relationships with stakeholders.While this phenomenon has attracted scholars largely from the heritage domain and film-induced tourism(hereafter FIT)discourse,the research has been minimal,is still evolving,and is located primarily in the global west;thus,more research in this area is needed.This paper responds to such gaps in the literature by studying a case from India,where scholarly knowledge on this phenomenon is scarce,available only in the FIT literature,and lacks a heritage conservation viewpoint.The selected case,the College of Agriculture in Pune,which has a colonial period structure and is one of the oldest educational institutes in India,has been officially branded as a filming location by the Film Facilitation Cell and Maharashtra Tourism Development Corporation.It has experienced a sudden rise in affection from its stakeholders and an upsurge in filming productions after its appearance in Bollywood’s blockbuster film Munna Bhai M.B.B.S.(Hirani,2003).Such activities have tended to impact the perceptions of stakeholders about the historical identity and architectural significance of the site and,ultimately,its conservation.The study presents this impact using qualitative methods,including focus group discussions and personal interviews of stakeholders:management staff,teachers,students,heritage walk leaders,and tourists.The responses were simultaneously juxtaposed with the film analysis method,giving rise to the interpretive themes of pride,narratives,celebrity associations,and architecture and planning.The research findings reveal that the stakeholder’s overall approach prioritises the site as an ideal filming location over its historical identity,compromising the ethics of heritage conservation and,thus,overshadowing the site’s architectural significance.Studying other effects of this phenomenon,such as heritage conservation challenges and FIT management,is beyond the scope of this paper.This study,therefore,is a preliminary step in this understudied area and establishes the pressing need for more rigorous and holistic knowledge production in heritage discourse,particularly in India. 展开更多
关键词 Filming location Architectural Heritage Historical Identity Stakeholder’s perception
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