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The multi-factor recombination and processes superimposition model for hydrocarbon accumulation:application to the Silurian in the Tarim Basin 被引量:9
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作者 Meng Qingyang Pang Xiongqi Gao Jianbo 《Petroleum Science》 SCIE CAS CSCD 2008年第1期13-19,共7页
The multi-factor recombination and processes superimposition model for hydrocarbon accumulation is put forward in view of the hydrocarbon geological characteristics of multiple episodes of structural evolution, multip... The multi-factor recombination and processes superimposition model for hydrocarbon accumulation is put forward in view of the hydrocarbon geological characteristics of multiple episodes of structural evolution, multiple sets of source-reservoir-seal assemblage, multiple cycles of hydrocarbon accumulation and multiple episodes of readjustment and reconstruction in the complex superimposed basins in China. It is a system including theories and methods that can help to predict favorable exploration regions. According to this model, the basic discipline for hydrocarbon generation, evolution and distribution in the superimposed basins can be summarized in multi-factor recombination, processes superimposition, multiple stages of oil filling and latest stage preservation. With the Silurian of the Tarim basin as an example, based on the reconstruction of the evolution history of the four factors (paleo-anticline, source rock, regional cap rock and kinematic equilibrium belt) controlling hydrocarbon accumulation, this model was adopted to predict favorable hydrocarbon accumulation areas and favorable exploration regions following structural destruction in three stages of oil filling, to provide guidance for further exploration ofoil and gas in the Silurian of the Tarim basin. 展开更多
关键词 multi-factor recombination processes superimposition Tarim Basin SILURIAN favorable exploration region prediction
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Multi-factor analysis of initial poor graft function after orthotopic liver transplantation 被引量:12
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作者 Chen, Hao Peng, Cheng-Hong +5 位作者 Shen, Bai-Yong Deng, Xia-Xing Shen, Chuan Xie, Jun-Jie Dong, Wei Li, Hong-Wei 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2007年第2期141-146,共6页
BACKGROUND: In the early period of orthotopic liver transplantation (OLT), initial poor graft function (IPGF) is one of the complications which leads to primary graft non-function (PGNF) in serious cases. This study s... BACKGROUND: In the early period of orthotopic liver transplantation (OLT), initial poor graft function (IPGF) is one of the complications which leads to primary graft non-function (PGNF) in serious cases. This study set out to establish the clinical risk factors resulting in IPGF after OLT. METHODS: Eighty cases of OLT were analyzed. The IPGF group consisted of patients with alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) above 1500 IU/L within 72 hours after OLT, while those in the non-IPGF group had values below 1500 IU/L. Recipient-associated factors before OLT analyzed were age, sex, primary liver disease and Child-Pugh classification; factors analyzed within the peri-operative period were non-heart beating time (NHBT), cold ischemia time (CIT), rewarming ischemic time (RWIT), liver biopsy at the end of cold ischemia; and factors analyzed within 72 hours after OLT were ALT and/or AST values. A logistic regression model was applied to filter the possible factors resulting in IPGF. RESULTS: Donor NHBT, CIT and RWIT were significantly longer in the IPGF group than in the non-IPGF group; in the logistic regression model, NHBT was the risk factor leading to IPGF (P < 0.05), while CIT and RWIT were possible risk factors. In one case in the IPGF group, PGNF appeared with moderate hepatic steatosis. CONCLUSIONS: Longer NHBT is an important risk factor leading to IPGF, while serious steatosis in the donor liver, CIT and RWIT are potential risk factors. 展开更多
关键词 orthotopic liver transplantation poor liver function multi-factor analysis
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Cellular Automata-based Chloride Ion Diffusion Simulation of Concrete Bridges under Multi-factor Coupling Actions 被引量:2
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作者 ZHU Jinsong HE Likun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第1期160-165,共6页
In order to accurately simulate the diffusion of chloride ion in the existing concrete bridge and acquire the precise chloride ion concentration at given time, a cellular automata (CA)-based model is proposed. The p... In order to accurately simulate the diffusion of chloride ion in the existing concrete bridge and acquire the precise chloride ion concentration at given time, a cellular automata (CA)-based model is proposed. The process of chloride ion diffusion is analyzed by the CA-based method and a nonlinear solution of the Fick's second law is obtained. Considering the impact of various factors such as stress states, temporal and spatial variability of diffusion parameters and water-cement ratio on the process of chloride ion diffusion, the model of chloride ion diffusion under multi-factor coupling actions is presented. A chloride ion penetrating experiment reported in the literature is used to prove the effectiveness and reasonability of the present method, and a T-type beam is taken as an illustrative example to analyze the process of chloride ion diffusion in practical application. The results indicate that CA-based method can simulate the diffusion of chloride ion in the concrete structures with acceptable precision. 展开更多
关键词 concrete bridge chloride ion diffusion cellular automata multi-factor coupling actions
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Investment in deepwater oil and gas exploration projects:a multi-factor analysis with a real options model 被引量:5
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作者 Xin-Hua Qiu Zhen Wang Qing Xue 《Petroleum Science》 SCIE CAS CSCD 2015年第3期525-533,共9页
Deepwater oil and gas projects embody high risks from geology and engineering aspects, which exert substantial influence on project valuation. But the uncer- tainties may be converted to additional value to the projec... Deepwater oil and gas projects embody high risks from geology and engineering aspects, which exert substantial influence on project valuation. But the uncer- tainties may be converted to additional value to the projects in the case of flexible management. Given the flexibility of project management, this paper extends the classical real options model to a multi-factor model which contains oil price, geology, and engineering uncertainties. It then gives an application example of the new model to evaluate deepwater oil and gas projects with a numerical analytical method. Compared with other methods and models, this multi-factor real options model contains more project information. It reflects the potential value deriving not only from oil price variation but also from geology and engi- neering uncertainties, which provides more accurate and reliable valuation information for decision makers. 展开更多
关键词 Investment decision - Real options multi-factor model Option pricing - Deepwater oil and gas
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基于Multi-Agent的无人机集群体系自主作战系统设计 被引量:1
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作者 张堃 华帅 +1 位作者 袁斌林 杜睿怡 《系统工程与电子技术》 EI CSCD 北大核心 2024年第4期1273-1286,共14页
针对无人集群自主作战体系设计中的关键问题,提出基于Multi-Agent的无人集群自主作战系统设计方法。建立无人集群各节点的Agent模型及其推演规则;对于仿真系统模块化和通用化的需求,设计系统互操作式接口和无人集群自主作战的交互关系;... 针对无人集群自主作战体系设计中的关键问题,提出基于Multi-Agent的无人集群自主作战系统设计方法。建立无人集群各节点的Agent模型及其推演规则;对于仿真系统模块化和通用化的需求,设计系统互操作式接口和无人集群自主作战的交互关系;开展无人集群系统仿真推演验证。仿真结果表明,所提设计方案不仅能够有效开展并完成自主作战网络生成-集群演化-效能评估的全过程动态演示验证,而且能够通过重复随机试验进一步评估无人集群的协同作战效能,最后总结了集群协同作战的策略和经验。 展开更多
关键词 multi-AGENT 无人集群 体系设计 协同作战
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A branch-and-bound algorithm for discrete multi-factor portfolio optimization model 被引量:1
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作者 牛淑芬 王国欣 孙小玲 《Journal of Shanghai University(English Edition)》 CAS 2008年第1期26-30,共5页
In this paper, a new branch-and-bound algorithm based on the Lagrangian dual relaxation and continuous relaxation is proposed for discrete multi-factor portfolio selection model with roundlot restriction in financial ... In this paper, a new branch-and-bound algorithm based on the Lagrangian dual relaxation and continuous relaxation is proposed for discrete multi-factor portfolio selection model with roundlot restriction in financial optimization. This discrete portfolio model is of integer quadratic programming problems. The separable structure of the model is investigated by using Lagrangian relaxation and dual search. Computational results show that the algorithm is capable of solving real-world portfolio problems with data from US stock market and randomly generated test problems with up to 120 securities. 展开更多
关键词 portfolio optimization discrete multi-factor model Lagrangian relaxation and continuous relaxation branch-and-bound method.
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Multi-factor sensitivity analysis of shallow unsaturated clay slope stability 被引量:1
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作者 ZhuoyingTan MeifengCai 《Journal of University of Science and Technology Beijing》 CSCD 2005年第3期193-202,共10页
An unsaturated clay slope, with various sloping angles and a thickness of 14 m, consists of backfill, slope soil and residual soil. Slide interfaces were determined by geophysical approaches and the original slope was... An unsaturated clay slope, with various sloping angles and a thickness of 14 m, consists of backfill, slope soil and residual soil. Slide interfaces were determined by geophysical approaches and the original slope was reconstructed. Sub-slope masses were classified based on the varieties of sloping angle. A force recursive principle was proposed to calculate the stability coefficient of the sub-slope masses. The influencing factors such as sloping angle, water content, hydrostatic pressure, seismic force as well as train load were analyzed. The range and correlation of the above-mentioned factors were discussed and coupled wave equations were established to reflect the relationships between unit weight, cohesion, internal frictional angle, and water content, as well as between internal frictional angle and cohesion. The sensitivity analysis of slope stability was carried out and susceptive factors were determined when the factors were taken as independent and dependent variables respectively. The results show that sloping angle, water content and earthquake are the principal susceptive factors influencing slope stability. The impact of hydrostatic pressure on slope stability is similar to the seismic force in quantity. Train load plays a small role in slope stability and its influencing only reaches the roadbed and its neighboring slope segment. If the factors are taken as independent variables, the influencing extent of water content and cohesion on slope stability can be weakened and train load can be magnified. 展开更多
关键词 unsaturated clay slope stability multi-factor sensitivity analysis
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Multi-factor high-order intuitionistic fuzzy timeseries forecasting model 被引量:1
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作者 Ya'nan Wang Yingjie Lei +1 位作者 Yang Lei Xiaoshi Fan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第5期1054-1062,共9页
Fuzzy sets theory cannot describe the neutrality degreeof data, which has largely limited the objectivity of fuzzy time seriesin uncertain data forecasting. With this regard, a multi-factor highorderintuitionistic fuz... Fuzzy sets theory cannot describe the neutrality degreeof data, which has largely limited the objectivity of fuzzy time seriesin uncertain data forecasting. With this regard, a multi-factor highorderintuitionistic fuzzy time series forecasting model is built. Inthe new model, a fuzzy clustering algorithm is used to get unequalintervals, and a more objective technique for ascertaining membershipand non-membership functions of the intuitionistic fuzzy setis proposed. On these bases, forecast rules based on multidimensionalintuitionistic fuzzy modus ponens inference are established.Finally, contrast experiments on the daily mean temperature ofBeijing are carried out, which show that the novel model has aclear advantage of improving the forecast accuracy. 展开更多
关键词 multi-factor high-order intuitionistic fuzzy time series forecasting model intuitionistic fuzzy inference.
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联合物理层与MAC层的multi-TRP上行重叠传输处理机制
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作者 景小荣 熊杰 +1 位作者 孙健 陈前斌 《通信学报》 EI CSCD 北大核心 2024年第8期110-124,共15页
针对非理想回程下现有协议难以有效处理多传输接收节点(multi-TRP)场景中多定时提前(multi-TA)导致的严重上行链路(UL)重叠传输问题,联合改进物理层复用技术和介质访问控制(MAC)令牌桶技术,提出了一种新型的UL重叠传输处理机制。该新型... 针对非理想回程下现有协议难以有效处理多传输接收节点(multi-TRP)场景中多定时提前(multi-TA)导致的严重上行链路(UL)重叠传输问题,联合改进物理层复用技术和介质访问控制(MAC)令牌桶技术,提出了一种新型的UL重叠传输处理机制。该新型机制通过改进物理层重叠信道识别流程、复用要求及复用规则,将物理层复用信息与重叠信息反馈至MAC层,并对MAC层令牌桶技术进行优化。通过仿真实验对所提机制与现有协议机制进行对比,结果表明,在逻辑时隙不可重叠和可重叠2种情形下,物理上行控制信道(PUCCH)实际复用数量性能平均提升了57.58%和49.40%,物理上行共享信道(PUSCH)实际可用资源数量性能平均提升了12.09%和26.03%;优先级最高逻辑信道实际占用资源数量性能平均提升了33.33%和45.48%。 展开更多
关键词 多传输接收节点 上行链路 重叠传输 信道复用 令牌桶
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Dividing the Expropriated Areas Based on Multi-Factor Comprehensive Evaluation—A Case Study of Gongcheng Yao Autonomous County
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作者 Yuening Song Xiangwen Cai +3 位作者 Mi Tang Mingyuan Liu Yan Zhao Zehao Liu 《Journal of Geographic Information System》 2020年第6期579-596,共18页
In recent years, with the rapid development of urbanization in China, land acquisition work is particularly important. The division of expropriated area is the primary factor to be considered when evaluating the compr... In recent years, with the rapid development of urbanization in China, land acquisition work is particularly important. The division of expropriated area is the primary factor to be considered when evaluating the comprehensive land price of expropriated area. Reasonable division can help to improve the scientific and applicability of the comprehensive land price of the region. How to maximize the protection of farmers’ rights and interests by the division of land requisition is an urgent problem to be solved. Taking Gongcheng Yao Autonomous County as an example, this study adopted the multi-factor comprehensive evaluation method to evaluate the division of land requisition in this area, and carried out the corresponding spatial analysis and data processing based on GIS technology. Gongcheng Yao Autonomous County was divided into levy areas, and the Delphi method was used to screen the impact factors and determine the weight of the levy areas. Reasonable division of land requisition area can provide references for land requisition area, make it more scientific and reasonable, and protect the rights and interests of farmers. 展开更多
关键词 Area Division multi Factor Comprehensive Evaluation ARCGIS DELPHI
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Enhancing Multi-Factor Authentication in Modern Computing
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作者 Ekwonwune Emmanuel Nwabueze Iwuoha Obioha Oju Onuoha 《Communications and Network》 2017年第3期172-178,共7页
Most network service providers like MTN Nigeria, currently use two-factor authentication for their 4G wireless networks. This exposes the network subscribers to identify theft and users data to security threats like s... Most network service providers like MTN Nigeria, currently use two-factor authentication for their 4G wireless networks. This exposes the network subscribers to identify theft and users data to security threats like snooping, sniffing, spoofing and phishing. There is need to curb these problems with the use of an enhanced multi-factor authentication approach. The objective of this work is to create a multi-factor authentication software for a 4G wireless network. Multi-factor authentication involves user’s knowledge factor, user’s possession factor and user’s inherence factor;that is who the user is to be presented before system access can be granted. The research methodologies used for this work include Structured System Analysis and Design Methodology, SSADM and Prototyping. The result of this work will be a Multi-factor authentications software. This software was designed with programming languages like ASP. NET, C# and Microsoft SQL Server for the database. 展开更多
关键词 Enhanced multi-factor AUTHENTICATION Rapid PROTOTYPING Security THREAT Encryption HACKERS PHISHING MALWARE Tokens
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基于Multi-Agent的水电站变压器故障诊断系统
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作者 乔丹 马鹏 王琦 《自动化技术与应用》 2024年第7期58-61,65,共5页
为了精准、快速完成水电站变压器的故障诊断,设计基于Multi-Agent的水电站变压器故障诊断系统。变压器状态监控agent将检测到的变压器故障信息发送给系统管理agent,系统管理agent通过通信agent将变压器故障信息发送给变压器故障诊断age... 为了精准、快速完成水电站变压器的故障诊断,设计基于Multi-Agent的水电站变压器故障诊断系统。变压器状态监控agent将检测到的变压器故障信息发送给系统管理agent,系统管理agent通过通信agent将变压器故障信息发送给变压器故障诊断agent,变压器故障诊断agent利用小波变换方法提取变压器故障特征,并将其作为IFOA-SVM模型输入,完成变压器故障分类后,获取变压器故障诊断结果,该结果通过通信agent显示给用户。实验表明,该系统可有效诊断变压器故障诊断,诊断成功率受系统故障信息丢失率的影响较小,诊断耗时、耗能小,并具有较高故障诊断成功率。 展开更多
关键词 multi-AGENT 水电站 变压器 故障诊断 小波变换
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Multi-factor Analysis Model for Improving Profit Management Using Excel in Shellfish Farming Projects
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作者 Zhuming ZHAO Changlin LIU +1 位作者 Xiujuan SHAN Jin YU 《Asian Agricultural Research》 2013年第11期21-23,共3页
By using a farm's data in Yantai City and the theory of Cost-Volume-Profit analysis and the financial management methods,this paper construct a multi-factor analysis model for improving profit management using Exc... By using a farm's data in Yantai City and the theory of Cost-Volume-Profit analysis and the financial management methods,this paper construct a multi-factor analysis model for improving profit management using Excel 2007 in Shellfish farming projects and describes the procedures to construct a multi-factor analysis model.The model can quickly calculate the profit,improve the level of profit management,find out the breakeven point and enhance the decision-making efficiency of businesses etc.It is also a thought of the application to offer suggestions for government decisions and economic decisions for corporations as a simple analysis tool.While effort has been exerted to construct a four-variable model,some equally important variables may not be discussed sufficiently due to limitation of the paper's space and the authors'knowledge.All variables can be listed in EXCEL 2007 and can be associated in a logical way to manage the profit of shellfish farming projects more efficiently and more practically. 展开更多
关键词 SHELLFISH FARMING Cost-Volume-Profit analysis MULT
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Productivity Testing Design Method of Multi-Factor Control for Unconsolidated Sandstone Gas Reservoir
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作者 Muwang Wu Hao Liang +2 位作者 Mingjie Zhang Dianqiang Sun Peng Zhong 《Engineering(科研)》 2016年第11期815-822,共8页
Reservoir safety, testing-string safety, and flow control are key factors that should be considered in deep-water unconsolidated sandstone gas well testing work system. Combined with the feature of testing reservoir, ... Reservoir safety, testing-string safety, and flow control are key factors that should be considered in deep-water unconsolidated sandstone gas well testing work system. Combined with the feature of testing reservoir, pipe string type and sea area, the required minimum testing flow rate during cleaning up process, as well as minimum test flow rate without hydrate generation, pipe string erosion critical production, the maximum testing flow rate without destroying sand formation and the minimum output of meeting the demand of development was analyzed;based on the above critical test flow rates, testing working system is designed. Field application showed that the designed work system effectively provided good guidance for field test operations;no sand production or hydrate generation happened during the test process;the test parameter evaluated the reservoir accurately;the safe and efficient test operation was achieved. 展开更多
关键词 multi-factor Control Productivity Testing Unconsolidated Sandstone Gas Well HYDRATE SANDING
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Multi Location Field Evaluation of BC1F2 Sorghum Populations for Striga Resistance in Niger
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作者 Ousseini Ardaly Abdou Aissata Mamadou Ibrahim +2 位作者 Yaw Eleblu John Saviour Ofori Kwadwo Ousmane Zakari Moussa 《American Journal of Plant Sciences》 CAS 2024年第10期1010-1021,共12页
In Niger, a landlocked country, sorghum is the second staple food cultivated over the country by smallholder farmer. The crop is important for human and animal consumption. Despite its importance, the crop is affected... In Niger, a landlocked country, sorghum is the second staple food cultivated over the country by smallholder farmer. The crop is important for human and animal consumption. Despite its importance, the crop is affected by biotic and abiotic constraints. Among those constraints, striga has a high impact on yield. In fact, to survive, farmers are growing their local preferred sorghum varieties wish is highly sensible to the weed. Striga management is a challenge that requires a permanent solution. In addition, the development of high-yielding Striga resistant genotypes will be appreciated by farmers. The development of striga resistance will be based on the breeding population performances under farmer’s diverse environmental conditions adaptation. The main objective of this study is to evaluate two breeding populations for striga resistance in two different environments at Boulke and Dibissou in Tahoua region, to identify the early and high-yielding striga tolerant genotypes under natural infestation. 展开更多
关键词 Striga Resistance SORGHUM Breeding Population multi Environment
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A Robust Approach for Multi Classification-Based Intrusion Detection through Stacking Deep Learning Models
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作者 Samia Allaoua Chelloug 《Computers, Materials & Continua》 SCIE EI 2024年第6期4845-4861,共17页
Intrusion detection is a predominant task that monitors and protects the network infrastructure.Therefore,many datasets have been published and investigated by researchers to analyze and understand the problem of intr... Intrusion detection is a predominant task that monitors and protects the network infrastructure.Therefore,many datasets have been published and investigated by researchers to analyze and understand the problem of intrusion prediction and detection.In particular,the Network Security Laboratory-Knowledge Discovery in Databases(NSL-KDD)is an extensively used benchmark dataset for evaluating intrusion detection systems(IDSs)as it incorporates various network traffic attacks.It is worth mentioning that a large number of studies have tackled the problem of intrusion detection using machine learning models,but the performance of these models often decreases when evaluated on new attacks.This has led to the utilization of deep learning techniques,which have showcased significant potential for processing large datasets and therefore improving detection accuracy.For that reason,this paper focuses on the role of stacking deep learning models,including convolution neural network(CNN)and deep neural network(DNN)for improving the intrusion detection rate of the NSL-KDD dataset.Each base model is trained on the NSL-KDD dataset to extract significant features.Once the base models have been trained,the stacking process proceeds to the second stage,where a simple meta-model has been trained on the predictions generated from the proposed base models.The combination of the predictions allows the meta-model to distinguish different classes of attacks and increase the detection rate.Our experimental evaluations using the NSL-KDD dataset have shown the efficacy of stacking deep learning models for intrusion detection.The performance of the ensemble of base models,combined with the meta-model,exceeds the performance of individual models.Our stacking model has attained an accuracy of 99%and an average F1-score of 93%for the multi-classification scenario.Besides,the training time of the proposed ensemble model is lower than the training time of benchmark techniques,demonstrating its efficiency and robustness. 展开更多
关键词 Intrusion detection multi classification deep learning STACKING NSL-KDD
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Mutual information oriented deep skill chaining for multi‐agent reinforcement learning
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作者 Zaipeng Xie Cheng Ji +4 位作者 Chentai Qiao WenZhan Song Zewen Li Yufeng Zhang Yujing Zhang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第4期1014-1030,共17页
Multi‐agent reinforcement learning relies on reward signals to guide the policy networks of individual agents.However,in high‐dimensional continuous spaces,the non‐stationary environment can provide outdated experi... Multi‐agent reinforcement learning relies on reward signals to guide the policy networks of individual agents.However,in high‐dimensional continuous spaces,the non‐stationary environment can provide outdated experiences that hinder convergence,resulting in ineffective training performance for multi‐agent systems.To tackle this issue,a novel reinforcement learning scheme,Mutual Information Oriented Deep Skill Chaining(MioDSC),is proposed that generates an optimised cooperative policy by incorporating intrinsic rewards based on mutual information to improve exploration efficiency.These rewards encourage agents to diversify their learning process by engaging in actions that increase the mutual information between their actions and the environment state.In addition,MioDSC can generate cooperative policies using the options framework,allowing agents to learn and reuse complex action sequences and accelerating the convergence speed of multi‐agent learning.MioDSC was evaluated in the multi‐agent particle environment and the StarCraft multi‐agent challenge at varying difficulty levels.The experimental results demonstrate that MioDSC outperforms state‐of‐the‐art methods and is robust across various multi‐agent system tasks with high stability. 展开更多
关键词 artificial intelligence techniques decision making intelligent multi‐agent systems
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Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea
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作者 Xin-Ru Wang Bao-Zhi Pan +2 位作者 Yu-Hang Guo Qing-Hui Wang Yao Guan 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期206-220,共15页
There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir evaluation.Howe... There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir evaluation.However,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably difficult.At the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous formations.To overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous rocks.Specifically,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric model.Then we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and porosity.However,it is always difficult to determine the elemental eigenvalues of different minerals in inversion.This paper uses multiple linear regression methods to solve this problem.Finally,an integrated inversion technique for altered igneous formations was developed.The results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray diffraction.The results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formations. 展开更多
关键词 Joint inversion Altered igneous rock Element correction method Lithology identification multi mineral volume model
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Improved Scatter Search Algorithm for Multi-skilled Personnel Scheduling of Ship Block Painting
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作者 Guanglei Jiao Zuhua Jiang +1 位作者 Jianmin Niu Wenjuan Yu 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第1期1-15,共15页
This paper focuses on the optimization method for multi-skilled painting personnel scheduling.The budget working time analysis is carried out considering the influence of operating area,difficulty of spraying area,mul... This paper focuses on the optimization method for multi-skilled painting personnel scheduling.The budget working time analysis is carried out considering the influence of operating area,difficulty of spraying area,multi-skilled workers,and worker’s efficiency,then a mathematical model is established to minimize the completion time. The constraints of task priority,paint preparation,pump management,and neighbor avoidance in the ship block painting production are considered. Based on this model,an improved scatter search(ISS)algorithm is designed,and the hybrid approximate dynamic programming(ADP)algorithm is used to improve search efficiency. In addition,the two solution combination methods of path-relinking and task sequence combination are used to enhance the search breadth and depth. The numerical experimental results show that ISS has a significant advantage in solving efficiency compared with the solver in small scale instances;Compared with the scatter search algorithm and genetic algorithm,ISS can stably improve the solution quality. Verified by the production example,ISS effectively shortens the total completion time of the production,which is suitable for scheduling problems in the actual painting production of the shipyard. 展开更多
关键词 ship painting personnel scheduling multi⁃skilled workers scatter search task constraints
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Integration of Multiple Spectral Data via a Logistic Regression Algorithm for Detection of Crop Residue Burned Areas:A Case Study of Songnen Plain,Northeast China
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作者 ZHANG Sumei ZHANG Yuan ZHAO Hongmei 《Chinese Geographical Science》 SCIE CSCD 2024年第3期548-563,共16页
The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate ... The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate estimation of cropland burned area is both crucial and challenging,especially for the small and fragmented burned scars in China.Here we developed an automated burned area mapping algorithm that was implemented using Sentinel-2 Multi Spectral Instrument(MSI)data and its effectiveness was tested taking Songnen Plain,Northeast China as a case using satellite image of 2020.We employed a logistic regression method for integrating multiple spectral data into a synthetic indicator,and compared the results with manually interpreted burned area reference maps and the Moderate-Resolution Imaging Spectroradiometer(MODIS)MCD64A1 burned area product.The overall accuracy of the single variable logistic regression was 77.38%to 86.90%and 73.47%to 97.14%for the 52TCQ and 51TYM cases,respectively.In comparison,the accuracy of the burned area map was improved to 87.14%and 98.33%for the 52TCQ and 51TYM cases,respectively by multiple variable logistic regression of Sentind-2 images.The balance of omission error and commission error was also improved.The integration of multiple spectral data combined with a logistic regression method proves to be effective for burned area detection,offering a highly automated process with an automatic threshold determination mechanism.This method exhibits excellent extensibility and flexibility taking the image tile as the operating unit.It is suitable for burned area detection at a regional scale and can also be implemented with other satellite data. 展开更多
关键词 crop residue burning burned area Sentinel-2 multi Spectral Instrument(MSI) logistic regression Songnen Plain China
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