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Evolution of United States Technology Alliance Strategy and Reshaping of International Strategic Landscape
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作者 Tang Xinhua 《Contemporary World》 2024年第4期20-24,共5页
Building a technology alliance is the main strategy for the United States to maintain its scientific and technological hegemony under its technopolitical strategic framework.After Joe Biden took office,the United Stat... Building a technology alliance is the main strategy for the United States to maintain its scientific and technological hegemony under its technopolitical strategic framework.After Joe Biden took office,the United States implemented“small yard with high fences”strategy for scientific and technological competition,as the first step toward building a technology alliance.The main goal is to restrict the flow of strategic emerging technologies and factors of innovation to rival countries. 展开更多
关键词 ALLIANCE MAINTAIN strategy
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Zero-determinant strategies in iterated multi-strategy games
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作者 GUO Jinli 《纯粹数学与应用数学》 2024年第3期381-393,共13页
Self-serving,rational agents sometimes cooperate to their mutual benefit.The two-player iterated prisoner′s dilemma game is a model for including the emergence of cooperation.It is generally believed that there is no... Self-serving,rational agents sometimes cooperate to their mutual benefit.The two-player iterated prisoner′s dilemma game is a model for including the emergence of cooperation.It is generally believed that there is no simple ultimatum strategy which a player can control the return of the other participants.The zero-determinant strategy in the iterated prisoner′s dilemma dramatically expands our understanding of the classic game by uncovering strategies that provide a unilateral advantage to sentient players pitted against unwitting opponents.However,strategies in the prisoner′s dilemma game are only two strategies.Are there these results for general multi-strategy games?To address this question,the paper develops a theory for zero-determinant strategies for multi-strategy games,with any number of strategies.The analytical results exhibit a similar yet different scenario to the case of two-strategy games.The results are also applied to the Snowdrift game,the Hawk-Dove game and the Chicken game. 展开更多
关键词 prisoner′s dilemma zero-determinant strategy multi-strategy game symmetric game
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Optimization Strategies of Na_(3)V_(2)(PO_(4))_(3) Cathode Materials for Sodium‑Ion Batteries
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作者 Jiawen Hu Xinwei Li +4 位作者 Qianqian Liang Li Xu Changsheng Ding Yu Liu Yanfeng Gao 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期204-251,共48页
Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural stab... Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural stability.However,the inherently poor electronic conductivity and sluggish sodium-ion diffusion kinetics of NVP material give rise to inferior rate performance and unsatisfactory energy density,which strictly confine its further application in SIBs.Thus,it is of significance to boost the sodium storage performance of NVP cathode material.Up to now,many methods have been developed to optimize the electrochemical performance of NVP cathode material.In this review,the latest advances in optimization strategies for improving the electrochemical performance of NVP cathode material are well summarized and discussed,including carbon coating or modification,foreign-ion doping or substitution and nanostructure and morphology design.The foreign-ion doping or substitution is highlighted,involving Na,V,and PO_(4)^(3−)sites,which include single-site doping,multiple-site doping,single-ion doping,multiple-ion doping and so on.Furthermore,the challenges and prospects of high-performance NVP cathode material are also put forward.It is believed that this review can provide a useful reference for designing and developing high-performance NVP cathode material toward the large-scale application in SIBs. 展开更多
关键词 Sodium-ion batteries Na_(3)V_(2)(PO_(4))_(3) Cathode materials Electrochemical performance Optimization strategies
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Construction of Early-warning Model for Plant Diseases and Pests Based on Improved Neural Network 被引量:2
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作者 曹志勇 邱靖 +1 位作者 曹志娟 杨毅 《Agricultural Science & Technology》 CAS 2009年第6期135-137,154,共4页
By studying principles and methods related to early-warning model of plant diseases and using PSO method, parameter optimization was conducted to backward propagation neural network, and a pre-warning model for plant ... By studying principles and methods related to early-warning model of plant diseases and using PSO method, parameter optimization was conducted to backward propagation neural network, and a pre-warning model for plant diseases based on particle swarm and neural network algorithm was established. The test results showed that the construction of early-warning model is effective and feasible, which will provide a via- ble model structure to establish the effective early-warning platform. 展开更多
关键词 Backward propagation neural network Particle swarm algorithm Plant diseases and pests early-warning model
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China agricultural outlook for 2015–2024 based on China Agricultural Monitoring and Early-warning System(CAMES) 被引量:12
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作者 XU Shi-wei LI Gan-qiong LI Zhe-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第9期1889-1902,共14页
The primary goal of Chinese agricultural development is to guarantee national food security and supply of major agricultural products. Hence, the scientiifc work on agricultural monitoring and early warning as wel as ... The primary goal of Chinese agricultural development is to guarantee national food security and supply of major agricultural products. Hence, the scientiifc work on agricultural monitoring and early warning as wel as agricultural outlook must be strengthened. In this study, we develop the China Agricultural Monitoring and Early-warning System (CAMES) on the basis of a comparative study of domestic and international agricultural outlook models. The system is a dynamic and multi-market partial equilibrium model that integrates biological mechanisms with economic mechanisms. This system, which includes 11 categories of 953 kinds of agricultural products, could dynamical y project agricultural market supply and demand, assess food security, and conduct scenario analysis at different spatial levels, time scale levels, and macro-micro levels. Based on the CAMES, the production, consumption, and trade of the major agricultural products in China over the next decade are projected. The fol owing conclusions are drawn:i) The production of major agricultural products wil continue to grow steadily, mainly because of the increase in yield. i ) The growth of agricultural consumption wil be slightly higher than that of agricultural production. Meanwhile, a high self-sufifciency rate is expected for cereals such as rice, wheat, and maize, with the rate being stable at around 97%. i i) Agricultural trade wil continue to thrive. The growth of soybean and milk im-ports wil slow down, but the growth of traditional agricultural exports such as vegetables and fruits is expected to continue. 展开更多
关键词 agricultural outlook PROJECTION China Agricultural Monitoring and early-warning System(CAMES) agriculture of China
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Deformation early-warning index for heightened gravity dam during impoundment period 被引量:10
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作者 Bo Chen Zi-shen Huang +1 位作者 Teng-fei Bao Zheng Zhu 《Water Science and Engineering》 EI CAS CSCD 2021年第1期54-64,共11页
The mechanical parameters of materials in a dam body and dam foundation tend to change when dams are reinforced in aging processes.It is important to use an early-warning index to reflect the safety status of dams,par... The mechanical parameters of materials in a dam body and dam foundation tend to change when dams are reinforced in aging processes.It is important to use an early-warning index to reflect the safety status of dams,particularly of heightened projects in the impoundment period.Herein,a new method for monitoring the safety status of heightened dams is proposed based on the deformation monitoring data of a dam structure,a statistical model,and finite-element numerical simulation.First,a fast optimization inversion method for estimation of dam mechanical parameters was developed,which used the water pressure component extracted from a statistical model,an improved inversion objective function,and a genetic optimization iterative algorithm.Then,a finite element model of a heightened concrete gravity dam was established,and the deformation behavior of the dam with rising water levels in the impoundment period was simulated.Subsequently,mechanical parameters of aged dam parts were calculated using the fast optimization inversion method with simulated deformation and the water pressure deformation component obtained by the statistical model under the same conditions of water pressure change.Finally,a new earlywarning index of dam deformation was constructed by means of the forward-simulated deformation and other components of the statistical model.The early-warning index is useful for forecasting dam deformation under different water levels,especially high water levels. 展开更多
关键词 Concrete gravity dam Parameter inverse analysis Structural health monitoring early-warning index Finite element simulation
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Characteristics Analysis and the Early-warning Service System of Heavy Fog in Chizhou City 被引量:5
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作者 齐建华 杨春雷 +2 位作者 阮玲 张仕清 房厚林 《Meteorological and Environmental Research》 CAS 2010年第5期71-75,79,共6页
By analyzing the heavy fog data in Chizhou City in recent 50 years(1959-2007),the general rules of meteorological elements variations were found when the heavy fog happened.The meteorological elements included the tem... By analyzing the heavy fog data in Chizhou City in recent 50 years(1959-2007),the general rules of meteorological elements variations were found when the heavy fog happened.The meteorological elements included the temperature,humidity,wind direction,wind speed,air pressure and so on.The conceptual models of high-altitude and ground situation were established when the heavy fog happened in Chizhou City.Based on considering sufficiently the special geographical environment in Chizhou City,we found the key factors which affected the local heavy fog via the relative analyses.By using the statistical forecast methods which included the second-level judgment method and regression method of event probability and so on,the forecast mode equation of heavy fog was established.Moreover,the objective forecast system of heavy fog in Chizhou City was also manufactured.It provided the basis and platform which could be referred for the heavy fog forecast,service and the release of early-warning signal. 展开更多
关键词 Heavy fog Climate characteristic Forecast method early-warning system China
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Data Processing Model of Coalmine Gas Early-Warning System 被引量:8
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作者 QIAN Jian-sheng YIN Hong-sheng +2 位作者 LIU Xiu-rong HUA Gang XU Yong-gang 《Journal of China University of Mining and Technology》 EI 2007年第1期20-24,共5页
The data processing mode is vital to the performance of an entire coalmine gas early-warning system, especially in real-time performance. Our objective was to present the structural features of coalmine gas data, so t... The data processing mode is vital to the performance of an entire coalmine gas early-warning system, especially in real-time performance. Our objective was to present the structural features of coalmine gas data, so that the data could be processed at different priority levels in C language. Two different data processing models, one with priority and the other without priority, were built based on queuing theory. Their theoretical formulas were determined via a M/M/I model in order to calculate average occupation time of each measuring point in an early-warning program. We validated the model with the gas early-warning system of the Huaibei Coalmine Group Corp. The results indicate that the average occupation time for gas data processing by using the queuing system model with priority is nearly 1/30 of that of the model without priority. 展开更多
关键词 gas early-warning data processing queuing theory priority model high efficiency
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A new early-warning prediction system for monitoring shear force of fault plane in the active fault 被引量:2
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作者 Manchao He Yu Wang Zhigang Tao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2010年第3期223-231,共9页
The most common method used to describe earthquake activity is based on the changes in physical parameters of the earth's surface such as displacement of active fault and seismic wave.However,such approach is not suc... The most common method used to describe earthquake activity is based on the changes in physical parameters of the earth's surface such as displacement of active fault and seismic wave.However,such approach is not successful in forecasting the movement behaviors of faults.In the present study,a new mechanical model of fault activity,considering the shear strength on the fault plane and the influence of the resistance force,is established based on the occurrence condition of earthquake.A remote real-time monitoring system is correspondingly developed to obtain the changes in mechanical components within fault.Taking into consideration the local geological conditions and the history of fault activity in Zhangjiakou of China,an active fault exposed in the region of Zhangjiakou is selected to be directly monitored by the real-time monitoring technique.A thorough investigation on local fault structures results in the selection of two suitable sites for monitoring potential active tectonic movements of Zhangjiakou fault.Two monitoring curves of shear strength,recorded during a monitoring period of 6 months,turn out to be steady,which indicates that the potential seismic activities hardly occur in the adjacent region in the near future.This monitoring technique can be used for early-warning prediction of the movement of active fault,and can help to further gain an insight into the interaction between fault activity and relevant mechanisms. 展开更多
关键词 active faults monitoring EARTHQUAKE early-warning system shear strength
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Risk Early-Warning Method for Natural Disasters Based on Integration of Entropy and DEA Model 被引量:4
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作者 Fengshan Wang Yan Cao Meng Liu 《Applied Mathematics》 2011年第1期23-32,共10页
Risk early-warning of natural disasters is a very intricate non-deterministic prediction, and it was difficult to resolve the conflicts and incompatibility of the risk structure. Risk early-warning factors of natural ... Risk early-warning of natural disasters is a very intricate non-deterministic prediction, and it was difficult to resolve the conflicts and incompatibility of the risk structure. Risk early-warning factors of natural disasters were differentiated into essential attributes and external characters, and its workflow mode was established on risk early-warning structure with integrated Entropy and DEA model, whose steps were put forward. On the basis of standard risk early-warning DEA model of natural disasters, weight coefficient of risk early-warning factors was determined with Information Entropy method, which improved standard risk early-warning DEA model with non-Archimedean infinitesimal, and established risk early-warning preference DEA model based on integrated entropy weight and DEA Model. Finally, model was applied into landslide risk early-warning case in earthquake-damaged emergency process on slope engineering, which exemplified the outcome could reflect more risk information than the method of standard DEA model, and reflected the rationality, feasibility, and impersonality, revealing its better ability on comprehensive safety and structure risk. 展开更多
关键词 ENTROPY Data Envelopment Analysis Comprehensive INTEGRATION ESSENTIAL ATTRIBUTE Risk early-warning Natural DISASTER
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The Innovation Research of Financial Early-Warning Index Measurement 被引量:3
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作者 Zhang You-tang Cheng Jun-ning Liang Wei-jun 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期281-284,共4页
The period economic fluctuation is vital for an enterprise to exist and further develop, it directly affect the enterprise financial health. So, it is significant to build up financial early-warning index and measure ... The period economic fluctuation is vital for an enterprise to exist and further develop, it directly affect the enterprise financial health. So, it is significant to build up financial early-warning index and measure the warning condition that the enterprise faces and take the effective measures to eliminate. We criticize Altman’sZ calculating model and build up some new indexes for enterprise financial early-warning condition measuring and making sound decision. 展开更多
关键词 financial early-warning index critical value cash earning value cash added value
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Early-warning signals for an outbreak of the influenza pandemic 被引量:2
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作者 任迪 高洁 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期461-464,共4页
Over the course of human history, influenza pandemics have been seen as major disasters, so studies on the influenza virus have become an important issue for many experts and scholars. Comprehensive research has been ... Over the course of human history, influenza pandemics have been seen as major disasters, so studies on the influenza virus have become an important issue for many experts and scholars. Comprehensive research has been performed over the years on the biological properties, chemical characteristics, external environmental factors and other aspects of the virus, and some results have been achieved. Based on the chaos game representation walk model, this paper uses the time series analysis method to study the DNA sequences of the influenza virus from 1913 to 2010, and works out the early-warning signals indicator value for the outbreak of an influenza pandemic. The variances in the CCR wall〈 sequences for the pandemic years (or + -1 to 2 years) are significantly higher than those for the adjacent years, while those in the non-pandemic years are usually smaller. In this way we can provide an influenza early-warning mechanism so that people can take precautions and be well prepared prior to a pandemic. 展开更多
关键词 influenza virus early-warning signals chaos game representation (CGR) walk model DNA sequence
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A study on the early-warning technique concerning debris flow disasters 被引量:1
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作者 ZHOU Jinxing, WANG Lixian, XIE Baoyuan, FEI Shimin, WANG Xilin (1. Inst. of Forestry Research, Chinese Academy of Forestry Science, Beijing 100091, China 2. College of Resource & Environment, Beijing Forestry University, Beijing 100083, China) 《Journal of Geographical Sciences》 SCIE CSCD 2002年第3期363-370,共8页
According to the principle of the eruption of debris flows, the new torrent classification techniques are brought forward. The torrent there can be divided into 4 types such as the debris flow torrent with high destru... According to the principle of the eruption of debris flows, the new torrent classification techniques are brought forward. The torrent there can be divided into 4 types such as the debris flow torrent with high destructive strength, the debris flow torrent, high sand-carrying capacity flush flood torrent and common flush flood by the techniques. In this paper, the classification indices system and the quantitative rating methods are presented. Based on torrent classification, debris flow torrent hazard zone mapping techniques by which the debris flow disaster early-warning object can be ascertained accurately are identified. The key techniques of building the debris flow disaster neural network (NN) real time forecasting model are given detailed explanations in this paper, including the determination of neural node at the input layer, the output layer and the implicit layer, the construction of knowledge source and the initial weight value and so on. With this technique, the debris flow disaster real-time forecasting neural network model is built according to the rainfall features of the historical debris flow disasters, which includes multiple rain factors such as rainfall of the disaster day, the rainfall of 15 days before the disaster day, the maximal rate of rainfall in one hour and ten minutes. It can forecast the probability, critical rainfall of eruption of the debris flows, through the real-time rainfall monitoring or weather forecasting. Based on the torrent classification and hazard zone mapping, combined with rainfall monitoring in the rainy season and real-time forecasting models, the debris flow disaster early-warning system is built. In this system, the GIS technique, the advanced international software and hardware are applied, which makes the system’s performance steady with good expansibility. The system is a visual information system that serves management and decision-making, which can facilitate timely inspect of the variation of the torrent type and hazardous zone, the torrent management, the early-warning of disasters and the disaster reduction and prevention. 展开更多
关键词 debris flows disaster early-warning technique torrent classification mapping of the hazard zones
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The Management Platform for Online Rate of Meteorological Early-warning Loudspeakers 被引量:1
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作者 Bing SHAO Baolei DONG Jifeng SONG 《Asian Agricultural Research》 2017年第2期57-58,共2页
The meteorological early-warning loudspeaker is a specific initiative for the meteorological departments to address the issues concerning issues concerning agriculture,countryside and farmers.Its significance is that ... The meteorological early-warning loudspeaker is a specific initiative for the meteorological departments to address the issues concerning issues concerning agriculture,countryside and farmers.Its significance is that it can promptly deliver the early-warning information concerning some meteorological disasters(such as torrential rains,typhoons,cold wave,hail)to the areas affected,so as to provide reference and protection for agricultural production and effectively reduce the loss of agricultural producers.Up to now,the meteorological early-warning loudspeakers in Benxi have covered the villages.However,due to irregular occurrence of meteorological disasters,the listeners will turn off the information receivers of meteorological early-warning loudspeakers when they fail to receive meteorological information for a long time,so that the users can not promptly know the early-warning information regarding some sudden meteorological disasters.In view of this,the meteorological departments have introduced a series of management measures,such as the daily use of loudspeakers to publish weather forecast information,aimed at improving the online rate and usage rate of meteorological loudspeakers.And the management platform for online rate of meteorological early-warning loudspeakers is an important part of the management system. 展开更多
关键词 Meteorological early-warning loudspeakers Weather LAN Storing process SMS
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Influence of social capital on the livelihood strategies of farmers under China's rural revitalization strategy in poor mountain areas: A case study of the Liangshan Yi autonomous prefecture 被引量:4
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作者 HE Ren-wei GUO Shi-li +1 位作者 DENG Xian ZHOU Kui 《Journal of Mountain Science》 SCIE CSCD 2022年第4期958-973,共16页
Social capital in the form of social resources or social networks is one of the most important livelihood capital of farmers, which can increase the labor productivity of poor households and increase income. It is imp... Social capital in the form of social resources or social networks is one of the most important livelihood capital of farmers, which can increase the labor productivity of poor households and increase income. It is important to explore the reasons underlying the livelihood strategy choices of farmers from the perspective of social capital under China’s rural revitalization strategy. In this study, the Liangshan Yi Autonomous Prefecture, a povertystricken mountainous area in southwestern China, was selected as the case study area, and multivariable linear regression models were constructed to analyze the influence of social capital on livelihood strategies.The results are as follows:(1) Individual social capital had a positive effect on non-agricultural livelihood strategies. On average, with a one-unit increase in individual social capital, the ratio of farmers’ nonagricultural income to total productive income(Income_Rto) increased by 0.002% and 0.062%,respectively. Collective social capital, with the Peasant Economic Cooperation Organization(PECO) as the carrier, had a negative effect on the non-agricultural livelihood strategies of farmers;on average, with a oneunit increase in PECO, Income_Rto decreased by approximately 0.053%. However, this effect was only significant in the river valley area.(2) The income differences among the different livelihood strategy types were explained by the livelihood strategy choices of farmers. As non-agricultural work can bring more benefits, the labor force exhibited one-way migration from villages to cities, resulting in a lack of the subject of rural revitalization. It is necessary to implement effective measures to highlight the role of PECO in increasing agricultural income for farmers. Finally,based on the above conclusions,policy recommendations with respect to livelihood transformation of farmers and rural sustainable development are discussed. 展开更多
关键词 Social capital Livelihood strategies Village types Rural revitalization Poor mountain areas Liangshan Yi Autonomous Prefecture
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Significant risk factors for intensive care unit-acquired weakness:A processing strategy based on repeated machine learning 被引量:10
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作者 Ling Wang Deng-Yan Long 《World Journal of Clinical Cases》 SCIE 2024年第7期1235-1242,共8页
BACKGROUND Intensive care unit-acquired weakness(ICU-AW)is a common complication that significantly impacts the patient's recovery process,even leading to adverse outcomes.Currently,there is a lack of effective pr... BACKGROUND Intensive care unit-acquired weakness(ICU-AW)is a common complication that significantly impacts the patient's recovery process,even leading to adverse outcomes.Currently,there is a lack of effective preventive measures.AIM To identify significant risk factors for ICU-AW through iterative machine learning techniques and offer recommendations for its prevention and treatment.METHODS Patients were categorized into ICU-AW and non-ICU-AW groups on the 14th day post-ICU admission.Relevant data from the initial 14 d of ICU stay,such as age,comorbidities,sedative dosage,vasopressor dosage,duration of mechanical ventilation,length of ICU stay,and rehabilitation therapy,were gathered.The relationships between these variables and ICU-AW were examined.Utilizing iterative machine learning techniques,a multilayer perceptron neural network model was developed,and its predictive performance for ICU-AW was assessed using the receiver operating characteristic curve.RESULTS Within the ICU-AW group,age,duration of mechanical ventilation,lorazepam dosage,adrenaline dosage,and length of ICU stay were significantly higher than in the non-ICU-AW group.Additionally,sepsis,multiple organ dysfunction syndrome,hypoalbuminemia,acute heart failure,respiratory failure,acute kidney injury,anemia,stress-related gastrointestinal bleeding,shock,hypertension,coronary artery disease,malignant tumors,and rehabilitation therapy ratios were significantly higher in the ICU-AW group,demonstrating statistical significance.The most influential factors contributing to ICU-AW were identified as the length of ICU stay(100.0%)and the duration of mechanical ventilation(54.9%).The neural network model predicted ICU-AW with an area under the curve of 0.941,sensitivity of 92.2%,and specificity of 82.7%.CONCLUSION The main factors influencing ICU-AW are the length of ICU stay and the duration of mechanical ventilation.A primary preventive strategy,when feasible,involves minimizing both ICU stay and mechanical ventilation duration. 展开更多
关键词 Intensive care unit-acquired weakness Risk factors Machine learning PREVENTION Strategies
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Novel Early-Warning Model for Customer Churn of Credit Card Based on GSAIBAS-Cat Boost
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作者 Yaling Xu Congjun Rao +1 位作者 Xinping Xiao Fuyan Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第12期2715-2742,共28页
As the banking industry gradually steps into the digital era of Bank 4.0,business competition is becoming increasingly fierce,and banks are also facing the problem of massive customer churn.To better maintain their cu... As the banking industry gradually steps into the digital era of Bank 4.0,business competition is becoming increasingly fierce,and banks are also facing the problem of massive customer churn.To better maintain their customer resources,it is crucial for banks to accurately predict customers with a tendency to churn.Aiming at the typical binary classification problem like customer churn,this paper establishes an early-warning model for credit card customer churn.That is a dual search algorithm named GSAIBAS by incorporating Golden Sine Algorithm(GSA)and an Improved Beetle Antennae Search(IBAS)is proposed to optimize the parameters of the CatBoost algorithm,which forms the GSAIBAS-CatBoost model.Especially,considering that the BAS algorithm has simple parameters and is easy to fall into local optimum,the Sigmoid nonlinear convergence factor and the lane flight equation are introduced to adjust the fixed step size of beetle.Then this improved BAS algorithm with variable step size is fused with the GSA to form a GSAIBAS algorithm which can achieve dual optimization.Moreover,an empirical analysis is made according to the data set of credit card customers from Analyttica official platform.The empirical results show that the values of Area Under Curve(AUC)and recall of the proposedmodel in this paper reach 96.15%and 95.56%,respectively,which are significantly better than the other 9 common machine learning models.Compared with several existing optimization algorithms,GSAIBAS algorithm has higher precision in the parameter optimization for CatBoost.Combined with two other customer churn data sets on Kaggle data platform,it is further verified that the model proposed in this paper is also valid and feasible. 展开更多
关键词 Customer churn early-warning model IBAS GSAIBAS-CatBoost
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Engineering Strategies for Suppressing the Shuttle Effect in Lithium–Sulfur Batteries 被引量:2
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作者 Jiayi Li Li Gao +7 位作者 Fengying Pan Cheng Gong Limeng Sun Hong Gao Jinqiang Zhang Yufei Zhao Guoxiu Wang Hao Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期187-221,共35页
Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-elect... Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-electron reaction between sulfur and lithium in liquid electrolyte makes the capacity much smaller than the theoretical value.Many methods were proposed for inhibiting the shuttle effect of polysulfide,improving corresponding redox kinetics and enhancing the integral performance of Li–S batteries.Here,we will comprehensively and systematically summarize the strategies for inhibiting the shuttle effect from all components of Li–S batteries.First,the electrochemical principles/mechanism and origin of the shuttle effect are described in detail.Moreover,the efficient strategies,including boosting the sulfur conversion rate of sulfur,confining sulfur or lithium polysulfides(LPS)within cathode host,confining LPS in the shield layer,and preventing LPS from contacting the anode,will be discussed to suppress the shuttle effect.Then,recent advances in inhibition of shuttle effect in cathode,electrolyte,separator,and anode with the aforementioned strategies have been summarized to direct the further design of efficient materials for Li–S batteries.Finally,we present prospects for inhibition of the LPS shuttle and potential development directions in Li–S batteries. 展开更多
关键词 Shuttle effect Designed strategies Li-S battery Lithium polysulfides
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New Sino-US Strategic Gambling and China’s Strategy
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作者 Wang Honggang 《Contemporary International Relations》 2019年第4期75-91,共17页
Since confidence is fading and anxiety is increasing in the US,America’s China policy has become more radical. In the short term, the US has the upper hand and China is in a relatively passive position. In the medium... Since confidence is fading and anxiety is increasing in the US,America’s China policy has become more radical. In the short term, the US has the upper hand and China is in a relatively passive position. In the medium-and long-term, there will be more balance between them. This current strategic gambling between China and the US will be the major issue of international politics in the first half of the 21 st century and the most prominent external challenge China faces. China needs to make strategic adjustments but the gamble may be worthwhile in correcting imbalance in the international order and in the co-evolution of the two countries. 展开更多
关键词 Sino-US RELATIONS STRATEGIC GAMBLING US strategy TOWARD China China’s strategy TOWARD the US
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Research on Technology Early-Warning System Based on Dynamic Information Monitoring
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作者 汪雪锋 朱东华 +1 位作者 刘嵩 刘佳 《Journal of Beijing Institute of Technology》 EI CAS 2009年第1期121-126,共6页
Relying on the advanced information technologies, such as information monitoring, data mining, natural language processing etc., the dynamic technology early-warning system is constructed. The system consists of techn... Relying on the advanced information technologies, such as information monitoring, data mining, natural language processing etc., the dynamic technology early-warning system is constructed. The system consists of technology information automatic retrieval, technology information monitoring, technology threat evaluation, and crisis response and management subsystem, which implements uninterrupted dynamic monitoring, trace and crisis early-warning to the specific technology. Empirical study testifies that the system improves the accuracy, timeliness and reliability of technology early-warning. 展开更多
关键词 technology early-warning system information monitoring dynamic retrieval technology threatevaluation crisis response and management
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