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Microdynamic mechanical properties and fracture evolution mechanism of monzogabbro with a true triaxial multilevel disturbance method

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International Journal of Mining Science and Technology 2024年第3期34卷 385-411页

作者： Zhi Zheng bin Deng Hong liu Wei Wang Shuling Huang Shaojun li State Key Laboratory of Featured Metal Materials and life-cycle Safety for Composite Structures Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationCollege of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources Changjiang River Scientific Research InstituteWuhan 430015China

The far-field microdynamic disturbance caused by the excavation of deep mineral resources and underground engineering can induce surrounding rock damage in high-stress conditions and even lead to ***,the mechanical properties and damage/fracture evolution mechanisms of deep rock induced by microdynamic disturbance under three-dimensional stress states are ***,a true triaxial multilevel disturbance test method is proposed,which can completely simulate natural geostress,excavation stress redistribution(such as stress unloading,concentration and rotation),and subsequently the microdynamic disturbance triggering damaged rock *** on a dynamic true triaxial test platform,true triaxial microdynamic disturbance tests under different frequency and amplitudes were carried out on *** results show that increasing amplitude or decreasing frequency diminishes the failure strength of *** modulus gradually decreases during disturbance *** frequency and amplitude increase,the degradation rate of deformation modulus decreases slightly,disturbance dissipated energy increases significantly,and disturbance deformation anisotropy strengthens obviously.A damage model has been proposed to quantitatively characterize the disturbance-induced damage evolution at different frequency and amplitude under true triaxial *** disturbance failure,the micro-tensile crack mechanism is dominant,and the micro-shear crack mechanism increases significantly at *** the increase of amplitude and frequency,the micro-shear crack mechanism *** approaching disturbance failure,the acoustic emission fractal dimension changes from a stable value to local large oscillation,and finally increases sharply to a high value at ***,the disturbance-induced failure mechanism of surrounding rock in deep engineering is clearly elucidated.

关键词： True triaxial disturbance test Mechanical properties Fracture evolution mechanism Disturbance-induced damage evolution Failure mechanism and precursor

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Development and validation of a new prognostic model for patients with acute-on-chronic liver failure in intensive care unit

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World Journal of Gastroenterology 2024年第20期30卷 2657-2676页

作者： Zong-Yi Zhu xiu-Hong Huang Hui-Qing Jiang li liu Department of Gastroenterology The Second Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Department of Gastroenterology Weixian People's HospitalXingtai 054700Hebei ProvinceChina

BACKGROUND Cirrhotic patients with acute-on-chronic liver failure(ACLF)in the intensive care unit(ICU)have a poor but variable *** prognosis evaluation can guide the rational management of patients with ***,existing prognostic scores for ACLF in the ICU environment lack sufficient *** To develop a new prognostic model for patients with ACLF in *** Data from 938 ACLF patients in the Medical Information Mart for Intensive Care(MIMIC)database were used to develop a new prognostic model(MIMIC ACLF)for ***,calibration and clinical utility of MIMIC ACLF were assessed by area under receiver operating characteristic curve(AUROC),calibration curve and decision curve analysis(DCA),*** ACLF was then externally validated in a multiple-center cohort,the Electronic Intensive Care Collaborative Research Database and a single-center cohort from the Second Hospital of Hebei Medical University in *** The MIMIC ACLF score was determined using nine variables:ln(age)×2.2+ln(white blood cell count)×0.22-ln(mean arterial pressure)×2.7+respiratory failure×0.6+renal failure×0.51+cerebral failure×0.31+ln(total bilirubin)×0.44+ln(internationalized normal ratio)×0.59+ln(serum potassium)×*** MIMIC cohort,the AUROC(0.81/0.79)for MIMIC ACLF for 28/90-day ACLF mortality were significantly greater than those of Chronic liver Failure Consortium ACLF(0.76/0.74),Model for End-stage liver Disease(MELD;0.73/0.71)and MELD-Na(0.72/0.70)(all Plinical utility of MIMIC ACLF were validated in the external *** We developed and validated a new prognostic model with satisfactory accuracy

关键词： Acute-on-chronic liver failure Cirrhosis Risk stratification Prognosis Model Scores

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Color-polarization synergistic target detection method considering shadow interference

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Defence Technology（防务技术） 2024年第7期37卷 50-61页

作者： bin Feng Jinpei Xiao Junchao Zhang lin li Yunlong Wu Qing Ye School of Automation Northwestern Polytechnical UniversityXi'an710072China School of Automation Central South UniversityChangsha410083China State Key Laboratory of Pulsed Power Laser Technology National University of Defense TechnologyHefei230037China

Aiming at the problem of shadow interference in UAV's ground reconnaissance,a color and polarization synergistic target detection method is proposed for anti-shadow interference,based on the influence of two physical characteristics(wavelength and polarization)under different illuminations.A valid fusion strategy is proposed via integrating two separate detection results on color and polarization ***,a local enhancement and recognition module(LER)is introduced to boost the *** on our built dataset,experimental results show that our method achieves mAPof 87.76%,and12.37%higher than that of color image and 14.68%higher than that of polarization image.

关键词： Electro-optical countermeasure Ground reconnaissance Color-polarization Shadow interference Target recognition

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A comprehensive review on the development of data-driven methods for wind power prediction and AGC performance evaluation in wind–thermal bundled power systems

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Energy and AI 2024年第2期16卷 450-463页

作者： Shuai Wang bin li Guanzheng li Botong li Hongbo li Kui Jiao Chengshan Wang National Industry-Education Platform for Energy Storage Tianjin UniversityTianjin300350China Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjin300072China Power Dispatching and Control Center Inner Mongolia Power(Group)Co.LtdHohhot010020China

The wind–thermal bundled power system achieves energy complementarity and optimized scheduling, which is an important way to build a new type of energy system. For the safe and stable operation of the wind–thermal bundled power system, accurate data-driven analysis is necessary to maintain real-time balance between electricity supply and demand. By summarizing the development and characteristics of wind–thermal bundled power system in China and different countries, current research in this field can be clearly defined in two aspects: short-term wind power prediction for wind farms and performance evaluation of automatic generation control (AGC) for thermal power generation units. For short-term wind power prediction, it is recommended to focus on historical data preprocessing and artificial intelligence methods. The technical characteristics of different data-driven wind power prediction methods have been compared in detail. For performance evaluation of AGC units, a comprehensive analysis was conducted on current evaluation methods, including the “permitted-band” and “regulation mileage” methods, as well as the issue of evaluation failure in traditional evaluation methods in practical engineering. Finally, the relative optimal dynamic performance of AGC units was discussed and the future trend of data-driven research in wind–thermal bundled power system was summarized.

关键词： Wind power prediction Automatic generation control Performance evaluation Data-driven Feature analysis

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Activity Pattern and Habitat Use of Shorebirds in an Artificial Wetland Complex:A Case Study of Breeding Pied Avocet in the Yellow River Delta,China

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Chinese Geographical Science 2024年第4期34卷 618-630页

作者： li Dong li bin XU He FAN Chao WU Yang ZHANG Yuxin HOU Xiyong Yantai Institute of Coastal Zone Research Chinese Academy of SciencesYantai 264003China Beijing VMinFull limited Beijing 100086China CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China University of Chinese Academy of Sciences Beijing 100049China School of Information Engineering Zhejiang Ocean UniversityZhoushan 316022China Key Laboratory for Biodiversity Science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing 100875China

With the loss of substantial natural wetlands in coastal zones,artificial wetlands provide alternative habitats for many *** management of artificial wetlands used by shorebirds plays an important role in maintaining the stability of shorebird *** tracking technique can obtain high-precision location information of individuals day and night,providing a good technical support for the study of quantitative relationship between waterfowls and their *** this study,satellite tracking method,Remote Sensing(RS)and Geographic Information System(GIS)technology were used to analyze the activity pattern and habitat utilization characteristics of Pied Avocet during breeding period in an artificial wetland complex in the Yellow River Delta(YRD),*** results showed that the breeding Pied Avocets had a small range of activity,with a total core and main home range of 33.10 km^(2) and 216.30 km^(2),*** species tended to forage in the pond and salt pan during the day and night,respectively,with an unfixed staying time in the breeding *** distance between breeding ground and feeding ground was less than 6 *** is emphasized that in addition to improving the conditions of the remaining natural habitats,effective managing artificial habitats is a priority for shorebird *** research could provide reference for the management of artificial wetlands in coastal zones and supply technique support for the protection of shorebirds and their habitats,and alleviate human-bird conflicts and sustainable development of coastal zones.

关键词： satellite tracking home range habitat use artificial wetland coastal zone Pied Avocet Yellow River Delta China

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Dynamic simulation analysis of molten salt reactor-coupled air-steam combined cycle power generation system

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Nuclear Science and Techniques 2024年第2期35卷 222-233页

作者： Jing-Lei Huang Guo-bin Jia li-Feng Han Wen-Qian liu li Huang Zheng-Han Yang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the molten salt reactor and power *** model considers the impact of thermal properties of fluid variation on accuracy and has been validated with *** study reveals the capability of the control system to compensate for anomalous situations and maintain shaft stability in the event of perturbations occurring in high-temperature molten salt tank outlet ***,the control system’s impact on the system’s dynamic characteristics under molten salt disturbance is also *** results reveal that after the disturbance occurs,the controlled system benefits from the action of the control,and the overshoot and disturbance amplitude are positively correlated,while the system power and frequency eventually return to the initial *** simulation model provides a basis for utilizing molten salt reactors for power generation and maintaining grid stability.

关键词： Molten salt reactor Combined cycle Dynamic characteristic Control

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Drag reduction characteristics of recirculation flow at rocket base in an RBCC engine under ramjet/scramjet mode

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Chinese Journal of Aeronautics 2024年第3期37卷 104-115页

作者： Menglei li Mingbo SUN Peibo li Daoning YANG bin AN Yizhi YAO Jikai CHEN Taiyu WANG Jiaoru WANG Hypersonic Technology Laboratory National University of Defense TechnologyChangsha 410073China Department of Aerospace Science and Technology Space Engineering UniversityBeijing 101416China

To reduce the drag generated by the recirculation flow at the rocket base in a RocketBased Combined Cycle(RBCC)engine operating in the ramjet/scramjet mode,a novel annular rocket RBCC engine based on a central plug cone was *** performance loss mechanism caused by the recirculation flow at the rocket base and the influence of the plug cone configuration on the thrust performance were *** indicated that the recirculation flow at the rocket base extended through the entire combustor,which creates an extensive range of the"low-kineticenergy zone"at the center and leads to an engine thrust *** plug cone serving as a surface structure had a restrictive effect on the internal flow of the engine,making it smoothly transit at the position of the large separation *** model RBCC engine could achieve a maximum thrust augmentation of 37.6%with a long plug cone that was twice diameter of the inner ***,a shorter plug cone that was half diameter of the inner isolator proved less effective at reducing the recirculation flow for a supersonic flow and induced an undesirable flow fraction that diminished the thrust ***,the effectiveness of the plug cone increased with the flight Mach number,indicating that it could further broaden the operating speed range of the scramjet mode.

关键词： Rocket-based combined cycle Ramjet/scramjet mode Plug cone Drag reduction k-x SST turbulent model

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Potential industrial applications of photo/electrocatalysis: Recent progress and future challenges

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Green Energy & Environment 2024年第5期9卷 859-876页

作者： Jinhao li Jing Ren Shaoquan li Guangchao li Molly Meng-Jung li Rengui li Young Soo Kang Xiaoxin Zou Yong Luo bin liu Yufei Zhao State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China Quzhou Institute for Innovation in Resource Chemical Engineering Quzhou324000China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing100029China Department of Applied Physics The Hong Kong Polytechnic UniversityHong Kong999077China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian National Laboratory for Clean EnergyZhongshan Road 457Dalian116023China Environmental and Climate Technology Track of Korea Institute of Energy Korea Institute of Energy TechnologyNaju-siJeollanam do58217Republic of Korea State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun130012China

Nowadays,the rapid development of the social economy inevitably leads to global energy and environmental *** this reason,more and more scholars focus on the development of photocatalysis and/or electrocatalysis technology for the advantage in the sustainable production of high-value-added products,and the high efﬁciency in pollutants *** there is plenty of outstanding research has been put forward continuously,most of them focuses on catalysis performance and reaction mechanisms in laboratory *** industrial application of photo/electrocatalytic processes is still a challenge that needs to be overcome by social *** this regard,this review comprehensively summarized several explorations in theﬁeld of photo/electrocatalytic reduction towards potential industrial applications in recent *** attention is paid to the successful attempts and the current status of photo/electrocatalytic water splitting,carbon dioxide conversion,resource utilization from waste,etc.,by using advanced *** key problems and challenges of photo/electrocatalysis in future industrial practice are also discussed,and the possible development directions are also pointed out from the industry view.

关键词： Photocatalysis Electrocatalysis Industrial applications H2 economy

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Analysis of Weakly Nonlinear Evolution Characteristics of Flow in the Constant Curvature Bend

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Advances in Applied Mathematics and Mechanics 2024年第1期16卷 101-121页

作者： bin li Haijue Xu Yuchuan Bai Ziqing Ji Skate Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Institute for Sedimentation on River and Coastal Engineering Tianjin 300072China

The meandering river is an unstable system with the characteristic of nonlinearity,which results from the instability of the flow and *** on the hydrodynamic nonlinearity of the bend,we use the weakly nonlinear theory and perturbation method to construct the nonlinear evolution equations of the disturbance amplitude and disturbance phase of two-dimensional flow in meandering *** influence of the curvature,Re and the disturbance wave number on the evolution of disturbance amplitude and disturbance phase are ***,the spatial and temporal evolution of the disturbance vorticity is *** research results show:that the curvature makes the flow more stable;that in the evolution of the disturbance amplitude effected by curvature,Re and the disturbance wave number,exist nonlinear attenuation with damping disturbances,and nonlinear explosive growth with positive disturbances;that the asymmetry distribution of the disturbance velocities increases with the curvature;that the location of the disturbance vorticity’s core area changes periodically with disturbance phase,and the disturbance vorticity gradually attenuates/increases with the decrease of the disturbance phase in the evolution process of damping/positive *** results shed light on the construction of the interaction model of hydrodynamic nonlinearity and geometric nonlinearity of bed.

关键词： Curvature bend hydrodynamics weakly nonlinearity disturbance vorticity

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PURP: A Scalable System for Predicting Short-Term Urban TrafficFlow Based on license Plate Recognition Data

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Big Data Mining and Analytics 2024年第1期7卷 171-187页

作者： Shan Zhang Qinkai Jiang Hao li bin Cao Jing Fan School of Computer Science and Technology Zhejiang University of TechnologyHangzhou 310000China

Accurate and efficient urban traffic flow prediction can help drivers identify road traffic conditions in real-time,consequently helping them avoid congestion and accidents to a certain ***,the existing methods for real-time urban traffic flow prediction focus on improving the model prediction accuracy or efficiency while ignoring the training efficiency,which results in a prediction system that lacks the scalability to integrate real-time traffic flow into the training *** conduct accurate and real-time urban traffic flow prediction while considering the latest historical data and avoiding time-consuming online retraining,herein,we propose a scalable system for Predicting short-term URban traffic flow in real-time based on license Plate recognition data(PURP).First,to ensure prediction accuracy,PURP constructs the spatio-temporal contexts of traffic flow prediction from license Plate Recognition(LPR)data as effective ***,to utilize the recent data without retraining the model online,PURP uses the nonparametric method k-Nearest Neighbor(namely KNN)as the prediction framework because the KNN can efficiently identify the top-k most similar spatio-temporal contexts and make predictions based on these contexts without time-consuming model retraining *** experimental results show that PURP retains strong prediction efficiency as the prediction period increases.

关键词： traffic flow prediction k-Nearest Neighbor(KNN) license Plate Recognition(LPR)data spatio-temporalcontext

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