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Machine learning of pyrite geochemistry reconstructs the multi-stage history of mineral deposits 被引量:1
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作者 Pengpeng Yu Yuan Liu +5 位作者 Hanyu Wang Xi Chen Yi Zheng Wei Cao Yiqu Xiong Hongxiang Shan 《Geoscience Frontiers》 2025年第3期81-93,共13页
The application of machine learning for pyrite discrimination establishes a robust foundation for constructing the ore-forming history of multi-stage deposits;however,published models face challenges related to limite... The application of machine learning for pyrite discrimination establishes a robust foundation for constructing the ore-forming history of multi-stage deposits;however,published models face challenges related to limited,imbalanced datasets and oversampling.In this study,the dataset was expanded to approximately 500 samples for each type,including 508 sedimentary,573 orogenic gold,548 sedimentary exhalative(SEDEX)deposits,and 364 volcanogenic massive sulfides(VMS)pyrites,utilizing random forest(RF)and support vector machine(SVM)methodologies to enhance the reliability of the classifier models.The RF classifier achieved an overall accuracy of 99.8%,and the SVM classifier attained an overall accuracy of 100%.The model was evaluated by a five-fold cross-validation approach with 93.8%accuracy for the RF and 94.9%for the SVM classifier.These results demonstrate the strong feasibility of pyrite classification,supported by a relatively large,balanced dataset and high accuracy rates.The classifier was employed to reveal the genesis of the controversial Keketale Pb-Zn deposit in NW China,which has been inconclusive among SEDEX,VMS,or a SEDEX-VMS transition.Petrographic investigations indicated that the deposit comprises early fine-grained layered pyrite(Py1)and late recrystallized pyrite(Py2).The majority voting classified Py1 as the VMS type,with an accuracy of RF and SVM being 72.2%and 75%,respectively,and confirmed Py2 as an orogenic type with 74.3% and 77.1%accuracy,respectively.The new findings indicated that the Keketale deposit originated from a submarine VMS mineralization system,followed by late orogenic-type overprinting of metamorphism and deformation,which is consistent with the geological and geochemical observations.This study further emphasizes the advantages of Machine learning(ML)methods in accurately and directly discriminating the deposit types and reconstructing the formation history of multi-stage deposits. 展开更多
关键词 Machine learning Random forest Support vector machine PYRITE multi-stage genesis Keketale deposit
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Spatiotemporal characteristics and influencing factors of vegetation water use efficiency on the Tibetan Plateau in 2001-2020 被引量:2
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作者 HE Chenyang WANG Yanjiao +1 位作者 YAN Feng LU Qi 《Journal of Geographical Sciences》 2025年第1期39-64,共26页
Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosyste... Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosystems.However,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain unclear.This study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–2020.Results indicated an annual mean WUE of 0.8088 gC/mm·m^(2)across the plateau,with a spatial gradient reflecting decrease from the southeast toward the northwest.Areas manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,respectively.Remarkably,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of increase.Environmental factors accounted for 70.79%of the variability in WUE.The leaf area index and temperature served as the major driving forces of WUE variation. 展开更多
关键词 water use efficiency spatiotemporal characteristic influencing factor Tibetan Plateau
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Multi-Stage Voltage Control Optimization Strategy for Distribution Networks Considering Active-Reactive Co-Regulation of Electric Vehicles
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作者 Shukang Lyu Fei Zeng +3 位作者 Huachun Han Huiyu Miao Yi Pan Xiaodong Yuan 《Energy Engineering》 EI 2025年第1期221-242,共22页
The high proportion of uncertain distributed power sources and the access to large-scale random electric vehicle(EV)charging resources further aggravate the voltage fluctuation of the distribution network,and the exis... The high proportion of uncertain distributed power sources and the access to large-scale random electric vehicle(EV)charging resources further aggravate the voltage fluctuation of the distribution network,and the existing research has not deeply explored the EV active-reactive synergistic regulating characteristics,and failed to realize themulti-timescale synergistic control with other regulatingmeans,For this reason,this paper proposes amultilevel linkage coordinated optimization strategy to reduce the voltage deviation of the distribution network.Firstly,a capacitor bank reactive power compensation voltage control model and a distributed photovoltaic(PV)activereactive power regulationmodel are established.Additionally,an external characteristicmodel of EVactive-reactive power regulation is developed considering the four-quadrant operational characteristics of the EVcharger.Amultiobjective optimization model of the distribution network is then constructed considering the time-series coupling constraints of multiple types of voltage regulators.A multi-timescale control strategy is proposed by considering the impact of voltage regulators on active-reactive EV energy consumption and PV energy consumption.Then,a four-stage voltage control optimization strategy is proposed for various types of voltage regulators with multiple time scales.Themulti-objective optimization is solved with the improvedDrosophila algorithmto realize the power fluctuation control of the distribution network and themulti-stage voltage control optimization.Simulation results validate that the proposed voltage control optimization strategy achieves the coordinated control of decentralized voltage control resources in the distribution network.It effectively reduces the voltage deviation of the distribution network while ensuring the energy demand of EV users and enhancing the stability and economic efficiency of the distribution network. 展开更多
关键词 Electric vehicle(EV) distribution network multi-stage optimization active-reactive power regulation voltage control
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A parameter-variant trochoidal-like tool path planning method for chatter-free and high-efficiency milling 被引量:1
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作者 Zhaoliang LI Jinbo NIU +1 位作者 Shuoxue SUN Yuwen SUN 《Chinese Journal of Aeronautics》 2025年第2期559-576,共18页
Trochoidal milling is known for its advantages in machining difficult-to-machine materials as it facilitates chip removal and tool cooling.However,the conventional trochoidal tool path presents challenges such as lowe... Trochoidal milling is known for its advantages in machining difficult-to-machine materials as it facilitates chip removal and tool cooling.However,the conventional trochoidal tool path presents challenges such as lower machining efficiency and longer machining time due to its time-varying cutter-workpiece engagement angle and a high percentage of non-cutting tool paths.To address these issues,this paper introduces a parameter-variant trochoidal-like(PVTR)tool path planning method for chatter-free and high-efficiency milling.This method ensures a constant engagement angle for each tool path period by adjusting the trochoidal radius and step.Initially,the nonlinear equation for the PVTR toolpath is established.Then,a segmented recurrence method is proposed to plan tool paths based on the desired engagement angle.The impact of trochoidal tool path parameters on the engagement angle is analyzed and coupled this information with the milling stability model based on spindle speed and engagement angle to determine the desired engagement angle throughout the machining process.Finally,several experimental tests are carried out using the bull-nose end mill to validate the feasibility and effectiveness of the proposed method. 展开更多
关键词 Trochoidal milling Milling stability Tool path planning Machining efficiency Bull-nose end mill
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Phase-change heterostructure with HfTe_(2)confinement sublayers for enhanced thermal efficiency and low-power operation through Joule heating localization 被引量:1
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作者 S.W.Park H.J.Lee +6 位作者 K.A.Nirmal T.H.Kim D.H.Kim J.Y.Choi J.S.Oh J.M.Joo T.G.Kim 《Journal of Materials Science & Technology》 2025年第1期104-114,共11页
Although phase-change random-access memory(PCRAM)is a promising next-generation nonvolatile memory technology,challenges remain in terms of reducing energy consumption.This is primarily be-cause the high thermal condu... Although phase-change random-access memory(PCRAM)is a promising next-generation nonvolatile memory technology,challenges remain in terms of reducing energy consumption.This is primarily be-cause the high thermal conductivities of phase-change materials(PCMs)promote Joule heating dissi-pation.Repeated phase transitions also induce long-range atomic diffusion,limiting the durability.To address these challenges,phase-change heterostructure(PCH)devices that incorporate confinement sub-layers based on transition-metal dichalcogenide materials have been developed.In this study,we engi-neered a PCH device by integrating HfTe_(2),which has low thermal conductivity and excellent stability,into the PCM to realize PCRAM with enhanced thermal efficiency and structural stability.HEAT sim-ulations were conducted to validate the superior heat confinement in the programming region of the HfTe_(2)-based PCH device.Moreover,electrical measurements of the device demonstrated its outstanding performance,which was characterized by a low RESET current(∼1.6 mA),stable two-order ON/OFF ratio,and exceptional cycling endurance(∼2×10^(7)).The structural integrity of the HfTe_(2)confinement sub-layer was confirmed using X-ray photoelectron spectroscopy and transmission electron microscopy.The material properties,including electrical conductivity,cohesive energy,and electronegativity,substantiated these findings.Collectively,these results revealed that the HfTe_(2)-based PCH device can achieve significant improvements in performance and reliability compared with conventional PCRAM devices. 展开更多
关键词 Phase-change random-access memory Phase-change heterostructure Thermal efficiency Thermal stability Low-power operation
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Application of a low-cost and high-efficiency polymer non-catalytic reduction technology for NO_(x) removal in waste-to-energy plant 被引量:1
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作者 Shuai Xiao Congbo Li +4 位作者 Xueyan Zheng Liya Li Jingzhong Si Xiuqi Shu Xianqiong Zeng 《Journal of Environmental Sciences》 2025年第12期112-125,共14页
Ultra-low emission of nitrogen oxide(NO_(x))is an irreversible trend for the development of waste-to-energy industry.But traditional approaches to remove NO_(x) face significant challenge s,such as low denitration eff... Ultra-low emission of nitrogen oxide(NO_(x))is an irreversible trend for the development of waste-to-energy industry.But traditional approaches to remove NO_(x) face significant challenge s,such as low denitration efficiency,complex denitration system,and high investment and operating cost.Here we put forward a novel polymer non-catalytic reduction(PNCR)technology that utilized a new type of polymer agent to remove NO_(x),and the proposed PNCR technology was applied to the existing waste-to-energy plant to test the denitration performance.The PNCR technology demonstrated excellent denitration performance with a NO_(x) emission concentration of<100 mg/Nm^(3) and high denitration efficiency of>75%at the temperature range of 800-900℃,which showed the application feasibility even on the complex and unstable industrial operating conditions.In addition,PNCR and hybrid polymer/selective non-catalytic reduction(PNCR/SNCR)technology possessed remarkable economic advantages including low investment fee and low operating cost of<10 CNY per ton of municipal solid waste(MSW)compared with selective catalytic reduction(SCR)technology.The excellent denitration performance of PNCR technology forebodes a broad industrial application prospect in the field of flue gas cleaning for waste-to-energy plants. 展开更多
关键词 Polymer non-catalytic reduction High denitration efficiency Low operating cost Waste-to-energy plant
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Dual‑Donor‑Induced Crystallinity Modulation Enables 19.23% Efficiency Organic Solar Cells
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作者 Anhai Liang Yuqing Sun +9 位作者 Sein Chung Jiyeong Shin Kangbo Sun Chaofeng Zhu Jingjing Zhao Zhenmin Zhao Yufei Zhong Guangye Zhang Kilwon Cho Zhipeng Kan 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期376-388,共13页
Trap-assisted charge recombination is one of the primary limitationsof restricting the performance of organic solar cells. However, effectivelyreducing the presence of traps in the photoactive layer remains challengin... Trap-assisted charge recombination is one of the primary limitationsof restricting the performance of organic solar cells. However, effectivelyreducing the presence of traps in the photoactive layer remains challenging.Herein, wide bandgap polymer donor PTzBI-dF is demonstrated as an effectivemodulator for enhancing the crystallinity of the bulk heterojunction active layerscomposed of D18 derivatives blended with Y6, leading to dense and orderedmolecular packings, and thus, improves photoluminescence quenching properties.As a result, the photovoltaic devices exhibit reduced trap-assisted charge recombinationlosses, achieving an optimized power conversion efficiency of over 19%.Besides the efficiency enhancement, the devices comprised of PTzBI-dF as athird component simultaneously attain decreased current leakage, improved chargecarrier mobilities, and suppressed bimolecular charge recombination, leading toreduced energy losses. The advanced crystalline structures induced by PTzBI-dFand its characteristics, such as well-aligned energy level, and complementaryabsorption spectra, are ascribed to the promising performance improvements.Our findings suggest that donor phase engineering is a feasible approach to tuning the molecular packings in the active layer, providingguidelines for designing effective morphology modulators for high-performance organic solar cells. 展开更多
关键词 Trap-assisted charge recombination PHOTOLUMINESCENCE MISCIBILITY Current leakage Power conversion efficiency
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Split nitrogen application increases maize root growth,yield,and nitrogen use efficiency under soil warming conditions 被引量:2
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作者 Zhenqing Xia Yuxiang Gong +3 位作者 Xiangyue Lyu Junchen Lin Yi Yang Haidong Lu 《The Crop Journal》 2025年第2期565-575,共11页
The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use e... The increase in soil temperature associated with climate change has introduced considerable challenges to crop production.Split nitrogen application(SN)represents a potential strategy for improving crop nitrogen use efficiency and enhancing crop stress resistance.Nevertheless,the precise interaction between soil warming(SW)and SN remains unclear.In order to ascertain the impact of SW on maize growth and whether SN can improve the tolerance of maize to SW,a two-year field experiment was conducted(2022-2023).The aim was to examine the influence of two SW ranges(MT,warming 1.40℃;HT,warming 2.75℃)and two nitrogen application methods(N1,one-time basal application of nitrogen fertilizer;N2,one third of base nitrogen fertilizer+two thirds of jointing stage supplemental nitrogen fertilizer)on maize root growth,photosynthetic characteristics,nitrogen use efficiency,and yield.The results demonstrated that SW impeded root growth and precipitated the premature aging of maize leaves following anthesis,particularly in the HT,which led to a notable reduction in maize yield.In comparison to N1,SN has been shown to increase root length density by 8.54%,root bleeding rate by 8.57%,and enhance root distribution ratio in the middle soil layers(20-60 cm).The interaction between SW and SN had a notable impact on maize growth and yield.The SN improved the absorption and utilization efficiency of nitrogen by promoting root development and downward canopy growth,thus improving the tolerance of maize to SW at the later stage of growth.In particular,the N2HT resulted in a 14.51%increase in the photosynthetic rate,a 18.58%increase in nitrogen absorption efficiency,and a 18.32%increase in maize yield compared with N1HT.It can be posited that the SN represents a viable nitrogen management measure with the potential to enhance maize tolerance to soil high-temperature stress. 展开更多
关键词 Maize(Zea mays L.) Soil warming Split nitrogen application Root growth Nitrogen use efficiency Grain yield
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An improved high efficiency low error substrate integrated waveguide wideband delay line
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作者 ZHANG Hongxi WANG Pei 《中国科学院大学学报(中英文)》 北大核心 2025年第5期677-685,共9页
In this paper,a wideband true time delay line for X-band is designed to overcome the beam dispersion problem in a high-resolution spaceborne synthetic aperture radar phased array antenna system.The delay line loads th... In this paper,a wideband true time delay line for X-band is designed to overcome the beam dispersion problem in a high-resolution spaceborne synthetic aperture radar phased array antenna system.The delay line loads the electromagnetic bandgap structure on the upper surface of the substrate integrated waveguide.This is equivalent to including an additional inductance-capacitance for energy storage,which realizes the slow-wave effect.A microstrip line-SIW tapered transition structure is introduced to achieve a low loss and a large bandwidth.In the frequency band between 8-12 GHz,the measured results show that the delay multiplier of the delay line reaches 4 times,i.e.,delay line’s delay time is 4 times larger than 50Ωmicrostrip line with same length.Furthermore,the delay fluctuation,i.e.,the difference between the maximum and minimum delay as a percentage of the standard delay is only 2.5%,the insertion loss is less than-2.5 dB,and the return loss is less than-15 dB.Compared with the existing delay lines,the proposed delay line has the advantages of high delay efficiency,low delay error,wide bandwidth and low loss,which has good practical value and application prospects. 展开更多
关键词 SIW EBG low error high efficiency WIDEBAND
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Energy Efficiency Operating Indicator Forecasting and Speed Design Optimization for Polar Ice Class Merchant Vessels
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作者 LU Yu LI Chen−ran +3 位作者 ZHU Xiang−hang LI Shi−an GU Zhu−hao LIU She−wen 《船舶力学》 北大核心 2025年第6期901-911,共11页
In order to accurately forecast the main engine fuel consumption and reduce the Energy Efficiency Operational Indicator(EEOI)of merchant ships in polar ice areas,the energy transfer relationship between ship-machine-p... In order to accurately forecast the main engine fuel consumption and reduce the Energy Efficiency Operational Indicator(EEOI)of merchant ships in polar ice areas,the energy transfer relationship between ship-machine-propeller is studied by analyzing the complex force situation during ship navigation and building a MATLAB/Simulink simulation platform based on multi-environmental resistance,propeller efficiency,main engine power,fuel consumption,fuel consumption rate and EEOI calculation module.Considering the environmental factors of wind,wave and ice,the route is divided into sections,the calculation of main engine power,main engine fuel consumption and EEOI for each section is completed,and the speed design is optimized based on the simulation model for each section.Under the requirements of the voyage plan,the optimization results show that the energy efficiency operation index of the whole route is reduced by 3.114%and the fuel consumption is reduced by 9.17 t. 展开更多
关键词 Energy efficiency Operational Indicator ice-class ships segment division design optimization
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Improving Provider Efficiency at the Local Level
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作者 Ronald Lagoe Shelly Littau 《Case Reports in Clinical Medicine》 2025年第1期1-9,共9页
This study reviewed developments in provider utilization related to health care in the metropolitan area of the Syracuse hospitals between the twentieth century and the twenty first century with respect to major hospi... This study reviewed developments in provider utilization related to health care in the metropolitan area of the Syracuse hospitals between the twentieth century and the twenty first century with respect to major hospital services. In this study, a decline in the utilization of inpatient hospitals developed between 2020 and 2022. During this period, use of additional outpatient services such as ambulatory surgery, individual practitioners, outside hospitals, and the use of hospital emergency departments developed in the community. The study data demonstrated that between 2020 and 2022, the numbers of discharges from the combined hospitals declined for both adult medicine and adult surgery. Inpatient discharges declined by 2730 patients for adult medicine and 1961 patients for adult surgery. The data also demonstrated that between 2022 and 2024, the numbers of discharges increased by 1998 discharges for adult medicine and by 229 for adult surgery. As followup to this study, health care providers and payors should review approaches to efficiency in their communities and evaluate their impact on health care efficiency. 展开更多
关键词 Health Care efficiency Hospitals Ambulatory Care
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Global Ports Efficiency and Productivity Using DEA-MPI Approach
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作者 Calvin Elorm Atsunyo Bernard Kwei Tetteh 《Open Journal of Applied Sciences》 2025年第2期433-449,共17页
Ports are crucial to the economy of many nations;thus, numerous studies have been conducted on port efficiency and productivity. This study analyses the efficiency and productivity of some major global ports namely, P... Ports are crucial to the economy of many nations;thus, numerous studies have been conducted on port efficiency and productivity. This study analyses the efficiency and productivity of some major global ports namely, Port of Singapore, Rotterdam, Antwerp and Durban. The main objectives of this study are to determine the level of operational efficiency of the mentioned ports, measure and evaluate the ports’ productivity changes and lastly to investigate the factors influencing the productivity changes of the ports studied. To achieve these objectives, Data Envelopment Analysis (DEA-BCC) model was used to determine the technical and operational efficiencies of the ports and Malmquist productivity index was employed to calculate the various productivity levels. The results of the study can guide stakeholders to formulate their operational strategies for port efficiency and productivity. The study also has policy suggestions that are uniquely targeted to Africa’s issues and potential. 展开更多
关键词 efficiency PRODUCTIVITY Data Envelopment Analysis Malmquist Productivity Index
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Multi-stage Mineralization in the Giant Erdaokan Ag-Pb-Zn Deposit,Northeastern China:Evidence from Magnetite EPMA and LA-ICPMS Geochemistry
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作者 FU Anzong LI Chenglu +6 位作者 YANG Wenpeng Masroor ALAM DENG Changzhou YANG Yuanjiang ZHENG Bo ZHAO Ruijun YUAN Maowen 《Acta Geologica Sinica(English Edition)》 2025年第2期532-552,共21页
Although previous researchers have attempted to decipher ore genesis and mineralization in the Erdaokan Ag-Pb-Zn deposit,some uncertainties regarding the mineralization process and evolution of both ore-forming fluids... Although previous researchers have attempted to decipher ore genesis and mineralization in the Erdaokan Ag-Pb-Zn deposit,some uncertainties regarding the mineralization process and evolution of both ore-forming fluids and magnetite types still need to be addressed.In this study,we obtained new EPMA,LA-ICP-MS,and in situ Fe isotope data from magnetite from the Erdaokan deposit,in order to better understand the mineralization mechanism and evolution of both magnetite and the ore-forming fluids.Our results identified seven types of magnetite at Erdaokan:disseminated magnetite(Mag1),coarse-grained magnetite(Mag2a),radial magnetite(Mag2b),fragmented fine-grained magnetite(Mag2c),vermicular gel magnetite(Mag3a1 and Mag3a2),colloidal magnetite(Mag3b)and dark gray magnetite(Mag4).All of the magnetite types were hydrothermal in origin and generally low in Ti(<400 ppm)and Ni(<800 ppm),while being enriched in light Fe isotopes(δ^(56)Fe ranging from−1.54‰to−0.06‰).However,they exhibit different geochemical signatures and are thus classified into high-manganese magnetite(Mag1,MnO>5 wt%),low-silicon magnetite(Mag2a-c,SiO_(2)<1 wt%),high-silicon magnetite(Mag3a-b,SiO_(2)from 1 to 7 wt%)and high-silicon-manganese magnetite(Mag4,SiO_(2)>1 wt%,MnO>0.2 wt%),each being formed within distinct hydrothermal environments.Based on mineralogy,elemental geochemistry,Fe isotopes,temperature trends,TMg-mag and(Ti+V)vs.(Al+Mn)diagrams,we propose that the Erdaokan Ag-Pb-Zn deposit underwent multi-stage mineralization,which can be broken down into four stages and nine sub-stages.Mag1,Mag2a-c,Mag3a-b and Mag4 were formed during the first sub-stage of each of the four stages,respectively.Additionally,fluid mixing,cooling and depressurization boiling were identified as the main mechanisms for mineral precipitation.The enrichment of Ag was significantly enhanced by the superposition of multi-stage ore-forming hydrothermal fluids in the Erdaokan Ag-Pb-Zn deposit. 展开更多
关键词 multi-stage mineralization magnetite geochemistry in situ Fe isotope Erdaokan Ag-Pb-Zn deposit
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Self-supervised multi-stage deep learning network for seismic data denoising
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作者 Omar M.Saad Matteo Ravasi Tariq Alkhalifah 《Artificial Intelligence in Geosciences》 2025年第1期240-249,共10页
Seismic data denoising is a critical process usually applied at various stages of the seismic processing workflow,as our ability to mitigate noise in seismic data affects the quality of our subsequent analyses.However... Seismic data denoising is a critical process usually applied at various stages of the seismic processing workflow,as our ability to mitigate noise in seismic data affects the quality of our subsequent analyses.However,finding an optimal balance between preserving seismic signals and effectively reducing seismic noise presents a substantial challenge.In this study,we introduce a multi-stage deep learning model,trained in a self-supervised manner,designed specifically to suppress seismic noise while minimizing signal leakage.This model operates as a patch-based approach,extracting overlapping patches from the noisy data and converting them into 1D vectors for input.It consists of two identical sub-networks,each configured differently.Inspired by the transformer architecture,each sub-network features an embedded block that comprises two fully connected layers,which are utilized for feature extraction from the input patches.After reshaping,a multi-head attention module enhances the model’s focus on significant features by assigning higher attention weights to them.The key difference between the two sub-networks lies in the number of neurons within their fully connected layers.The first sub-network serves as a strong denoiser with a small number of neurons,effectively attenuating seismic noise;in contrast,the second sub-network functions as a signal-add-back model,using a larger number of neurons to retrieve some of the signal that was not preserved in the output of the first sub-network.The proposed model produces two outputs,each corresponding to one of the sub-networks,and both sub-networks are optimized simultaneously using the noisy data as the label for both outputs.Evaluations conducted on both synthetic and field data demonstrate the model’s effectiveness in suppressing seismic noise with minimal signal leakage,outperforming some benchmark methods. 展开更多
关键词 Seismic data denoising Self-supervised multi-stage deep learning
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Multiple Efforts to Improve Health Care Efficiency
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作者 Ronald Lagoe Shelly Littau 《Case Reports in Clinical Medicine》 2025年第2期98-105,共8页
This study reviewed a combination of health care programs in the metropolitan area of Syracuse, New York. They were designed to improve care, however a major purpose was to support efficiency. The study described a nu... This study reviewed a combination of health care programs in the metropolitan area of Syracuse, New York. They were designed to improve care, however a major purpose was to support efficiency. The study described a number of individual programs that were developed in order to improve the quality and the efficiency of care. These programs were implemented by a combination of local providers and payors. They included the development of outpatient services such as ambulatory surgery, as well as preventive care, case management, telemedicine, and mental health. The impact of these programs was a combination of these services, rather than individual efforts. The impact of these efforts was the product of a range of individual services, especially care management. Additional efforts should make it possible to extend these efforts among providers and payors in the Syracuse area. This approach should make it possible to extend the impact of health care efficiency further. 展开更多
关键词 Health Care efficiency Health Care Payors Health Care Providers
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Root morphological adaptation and leaf lipid remobilization drive differences in phosphorus use efficiency in rapeseed seedlings
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作者 Bingbing Zhang Xinxin Zhu +11 位作者 Pan Yuan Bei Han Tao Wu Ismail Din Chuang Wang John P.Hammond Sheliang Wang Guangda Ding Hongmei Cai Zhuqing Zhao Fangshen Xu Lei Shi 《The Crop Journal》 2025年第2期524-535,共12页
With the objective of investigating the basis of phosphorus(P)utilization efficiency(PUE),physiological and morphological traits,two P-efficient and two P-inefficient rapeseed(Brassica napus L.)cultivars were compared... With the objective of investigating the basis of phosphorus(P)utilization efficiency(PUE),physiological and morphological traits,two P-efficient and two P-inefficient rapeseed(Brassica napus L.)cultivars were compared at the seedling stage.P-efficient cultivars showed root morphological adaptation,high P uptake activity,and greater phospholipid degradation under low P stress.Improving root morphological adaptation and reducing lipid-P allocation could allow increasing PUE in rapeseed seedlings. 展开更多
关键词 Root morphology Root exudates Phosphorus acquisition efficiency Phosphorus utilization efficiency P fractions
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Knowledge Modeling and Institutional Memory at the University of Cape Coast: Examining Technology as a Mediator and Leadership Styles as a Moderator in Enhancing Administrative Efficiency
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作者 Harriette Nusrat Manu Eleanor Afua Onyame +2 位作者 Eunice Amoako Mensah Sarah Annim Sayibu Abdul-Gafaar 《Intelligent Information Management》 2025年第1期1-30,共30页
The integration of digital tools and effective knowledge management practices is critical for enhancing administrative efficiency and institutional continuity in higher education. This study investigates the relations... The integration of digital tools and effective knowledge management practices is critical for enhancing administrative efficiency and institutional continuity in higher education. This study investigates the relationships between knowledge modeling, institutional memory, leadership styles, technology, and administrative efficiency at the University of Cape Coast (UCC). The study sought to identify the challenges and opportunities in integrating digital tools into administrative processes and to provide actionable recommendations for improvement. A mixed-methods research design was employed, combining quantitative analysis using Partial Least Squares Structural Equation Modeling (PLS-SEM) with qualitative thematic analysis of interviews. The findings revealed key challenges, including resistance to change, fragmented knowledge repositories, and inadequate funding, alongside opportunities such as centralized knowledge systems, cost-effective open-source tools, and capacity-building initiatives. The study highlights the importance of strategic leadership, robust policies, and investments in digital infrastructure to enhance administrative practices. Policy implications include the need for clear digital transformation guidelines and leadership training to foster innovation and collaboration. Recommendations include investing in scalable digital tools, implementing comprehensive capacity-building programs, and promoting stakeholder engagement to drive successful digital integration. These insights provide a roadmap for UCC and similar institutions seeking to optimize administrative efficiency through digital transformation. 展开更多
关键词 Knowledge Management Institutional Memory Digital Integration Technology Adoption Administrative efficiency Leadership Styles Centralised Knowledge Repositories
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New unloading criterion for enhancing multi-stage triaxial tests based on radial strain gradient
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作者 Guodong Jin Shujath Ali Syed +3 位作者 Héctor JoséGonzález-Pérez Hyung Tae Kwak Ali Abdullah Yousef Ali Abdullah Al Dhamen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期4735-4744,共10页
This paper presents a new criterion for determining the unloading points quantitatively and consistently in a multi-stage triaxial test.The radial strain gradient(RSG)is first introduced as an arc tangent function of ... This paper presents a new criterion for determining the unloading points quantitatively and consistently in a multi-stage triaxial test.The radial strain gradient(RSG)is first introduced as an arc tangent function of the rate of change of radial strain to time.RSG is observed to correlate closely with the stress state of a compressed sample,and reaches a horizontal asymptote as approaching failure.For a given rock type,RSG value at peak stress is almost the same,irrespective of the porosity and permeability.These findings lead to the development of RSG criterion:Unloading points can be precisely determined at the time when RSG reaches a pre-determined value that is a little smaller than or equal to the RSG at peak stress.The RSG criterion is validated against other criteria and the single-stage triaxial test on various types of rocks.Failure envelopes from the RSG criterion match well with those from single-stage tests.A practical procedure is recommended to use the RSG criterion:an unconfined compression or single-stage test is first conducted to determine the RSG at peak stress for one sample,the unloading point is then selected to be a value close to the RSG at peak stress,and the multi-stage test is finally performed on another sample using the pre-selected RSG unloading criterion.Generally,the RSG criterion is applicable for any type of rocks,especially brittle rocks,where other criteria are not suitable.Further,it can be practically implemented on the most available rock mechanical testing instruments. 展开更多
关键词 Radial strain gradient Unloading criterion multi-stage triaxial test Mohr-coulomb failure envelope
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Multi-stage and multi-objective optimization of anti-typhoon evacuation strategy for riser with new hang-off system
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作者 Yan-Wei Li Xiu-Quan Liu +3 位作者 Peng-Ji Hu Xiao-Yu Hu Yuan-Jiang Chang Guo-Ming Chen 《Petroleum Science》 2025年第1期457-471,共15页
A new hang-off system has been proposed to improve the security of risers in hang-off modes during typhoons.However,efficient anti-typhoon evacuation strategies have not been investigated.Optimiza-tion model and metho... A new hang-off system has been proposed to improve the security of risers in hang-off modes during typhoons.However,efficient anti-typhoon evacuation strategies have not been investigated.Optimiza-tion model and method for the anti-typhoon evacuation strategies should be researched.Therefore,multi-objective functions are proposed based on operation time,evacuation speed stability,and steering stability.An evacuation path model and a dynamic model of risers with the new hang-off system are developed for design variables and constraints.A multi-objective optimization model with high-dimensional variables and complex constraints is established.Finally,a three-stage optimization method based on genetic algorithm,least square method,and the penalty function method is proposed to solve the multi-objective optimization model.Optimization results show that the operation time can be reduced through operation parameter optimization,especially evacuation heading optimization.The optimal anti-typhoon strategy is evacuation with all risers suspended along a variable path when the direction angle is large,while evacuation with all risers suspended along a straight path at another di-rection angle.Besides,the influencing factors on anti-typhoon evacuation strategies indicate that the proposed optimization model and method have strong applicability to working conditions and remarkable optimization effects. 展开更多
关键词 Anti-typhoon evacuation strategy RISER multi-stage and multi-objective Optimization Genetic algorithm Least square method
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Optimizing Efficiency and Performance in a Rankine Cycle Power Plant Analysis
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作者 Ramesh Kumar Abdullah Bin Queyam +2 位作者 Manish Kumar Singla Mohamed Louzazni Mishra Dipak Kumar 《Energy Engineering》 2025年第4期1373-1386,共14页
Enhancing the efficiency of Rankine cycles is crucial for improving the performance of thermal power plants,as it directly impacts operational costs and emissions in light of energy transition goals.This study sets it... Enhancing the efficiency of Rankine cycles is crucial for improving the performance of thermal power plants,as it directly impacts operational costs and emissions in light of energy transition goals.This study sets itself apart from existing research by applying a novel optimization technique to a basic ideal Rankine cycle,focusing on a specific power plant that has not been previously analyzed.Currently,this cycle operates at 41%efficiency and a steam quality of 76%,constrained by fixed operational parameters.The primary objectives are to increase thermal efficiency beyond 46%and raise steam quality above 85%,while adhering to operational limits:a boiler pressure not exceeding 15 MPa,condenser pressure not dropping below 10 kPa,and turbine temperature not surpassing 500℃.This study utilizes numerical simulations to model the effects of varying boiler pressure(Pb)and condenser pressure(Pc)within the ranges of 12MPa<Pb<15 MPa and 5 kPa<Pc<10 kPa.By systematically adjusting these parameters,the proposed aimto identify optimal conditions that maximize efficiency and performance within specified constraints.The findings will provide valuable insights for power plant operators seeking to optimize performance under real-world conditions,contributing to more efficient and sustainable power generation. 展开更多
关键词 Rankine cycle thermal efficiency steamquality boiler pressure condenser pressure cycle performance operational constraints efficiency improvement
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