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Visualization analysis of the capability of weapon system of systems for multi-dimensional indicators 被引量:1
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作者 Jianfei Ding Guangya Si +2 位作者 Guoqiang Yang Yang Liu Xiao Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第2期292-300,共9页
In the field of weapon system of systems (WSOS) simulation, various indicators are widely used to describe the capability of WSOS, but it is always difficult to describe the comprehensive capability of WSOS quickly an... In the field of weapon system of systems (WSOS) simulation, various indicators are widely used to describe the capability of WSOS, but it is always difficult to describe the comprehensive capability of WSOS quickly and intuitively by visualization of multi-dimensional indicators. A method of machine learning and visualization is proposed, which can display and analyze the capabilities of different WSOS in a two-dimensional plane. The analysis and comparison of the comprehensive capability of different components of WSOS is realized by the method, which consists of six parts: multiple simulations, key indicators mining, three spatial distance calculation, fusion project calculation, calculation of individual capability density, and calculation of multiple capability ranges overlay. Binding a simulation experiment, the collaborative analysis of six indicators and 100 possible kinds of red WSOS are achieved. The experimental results show that this method can effectively improve the quality and speed of capabilities analysis, reveal a large number of potential information, and provide a visual support for the qualitative and quantitative analysis model. 展开更多
关键词 weapon system of systems (WSOS) comprehensive capability visualization of multi-dimensional indicators machine learning
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Tectonic Implications of the Combined Use of Tectonomagmatic Geochemical Discrimination Diagrams and Indicators of Magma Flow Sense in Mafic Dykes
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作者 Elson P.OLIVEIRA Sanjeet K.VERMA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期39-,共1页
Geochemistry is a powerful tool to help characterize the tectonic setting of igneous rocks associations.However,when continental mafic dykes and flood basalts are the target most of the proposed geochemical discrimina... Geochemistry is a powerful tool to help characterize the tectonic setting of igneous rocks associations.However,when continental mafic dykes and flood basalts are the target most of the proposed geochemical discrimination diagrams fail to correctly classify them,i.e.many mafic 展开更多
关键词 In Tectonic Implications of the combined Use of Tectonomagmatic Geochemical Discrimination Diagrams and indicators of Magma Flow Sense in Mafic Dykes
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Intervention effect of combined resistance and aerobic exercise on type 2 diabetes: A meta-analysis 被引量:1
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作者 Jiang-Chen Ma Song Shu +3 位作者 Tian-Xiao Chen Hui-Jing Bai Ya Yang Xiao-Wei Ding 《World Journal of Diabetes》 2025年第7期370-380,共11页
BACKGROUND Type 2 diabetes mellitus(T2DM),a chronic metabolic disease with a high global incidence,has become a serious public health challenge.China has the largest number of T2DM patients worldwide,imposing a signif... BACKGROUND Type 2 diabetes mellitus(T2DM),a chronic metabolic disease with a high global incidence,has become a serious public health challenge.China has the largest number of T2DM patients worldwide,imposing a significant economic burden on the healthcare system.T2DM is closely associated with insulin resistance,impaired pancreatic B cell function,and disordered glucose and lipid metabolism,which can lead to various complications,reducing patients'quality of life and increasing the risk of disability and death.Thus,finding effective preventive and intervention measures is crucial.Exercise therapy,a key part of diabetes management,has gained attention in recent years,with many studies indicating its benefits for blood glucose control and other aspects in diabetic patients.AIM To assess the effectiveness of combined resistance and aerobic exercise interventions on blood glucose control and metabolic indicators in patients with T2DM and to explore their application in diabetes management.METHODS Systematic searches were conducted using PubMed,EMBASE,Cochrane Library,and Chinese databases for relevant randomized controlled trials(RCTs).The inclusion criteria were participants aged≥18 years with T2DM and the intervention involved combined resistance and aerobic exercise for≥8 weeks.The primary outcome indicators were fasting blood glucose,low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C),triglycerides(TG),glycated hemoglobin A1c(HbA1c),and total cholesterol(TC)levels.Data analysis was performed using RevMan software,and the interventional effects were assessed using weighted mean differences or standardized mean differences(SMD).RESULTS Six RCTs meeting the inclusion criteria were included,with a total sample size of 366 participants.The meta-analysis results showed that combined resistance and aerobic exercise significantly improved several metabolic indicators in patients with T2DM.Specific results were as follows:(1)For fasting blood glucose,combined exercise was more effective than aerobic exercise alone[SMD=1.22;95%confidence interval(95%CI):0.70,1.74;P<0.00001];(2)LDL-C levels were significantly reduced by the combined intervention(SMD=1.45;95%CI:1.18-1.72;P<0.00001);(3)The combined intervention significantly increased HDL-C levels(SMD=1.42;95%CI:0.98-1.87;P<0.00001);(4)The combined intervention significantly reduced TG levels(SMD=1.12;95%CI:0.85-1.39;P<0.00001;(5)No statistically significant difference was observed in HbA1c between the combined and the aerobic exercise group(SMD=-0.03;95%CI:-1.09 to 1.04;P<0.00001);and(6)The combined exercise intervention group significantly reduced TC levels(SMD=2.66;95%CI:1.93-3.38;P<0.00001).The subgroup analysis results suggest that the effect of exercise interventions may be influenced by various factors,including the patient's age,baseline blood glucose levels,and exercise intensity.CONCLUSION Combined resistance and aerobic exercise intervention significantly improved fasting blood glucose,LDL-C,HDL-C,TG,and TC levels in patients with T2DM,especially in terms of blood glucose control and cardiovascular risk,demonstrating better outcomes than aerobic exercise alone. 展开更多
关键词 Type 2 diabetes combined resistance exercise Aerobic exercise META-ANALYSIS Blood glucose control Metabolic indicators
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Research to Establish a Set of Combinatorial Indicators to Calculate Flood Vulnerability Index in Thach Han-Ben Hai River Basin, Quang Tri Province, Vietnam 被引量:1
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作者 Ngo Chi Tuan Nguyen Thanh Son +1 位作者 Nguyen Kien Dung Can Thu Van 《Journal of Environmental Science and Engineering(B)》 2021年第4期138-150,共13页
In recent times,approaches to flood prevention and mitigation have changed a lot.These changes are to shift the focus from flood control to flood risk management,in which the assessment of vulnerability to floods caus... In recent times,approaches to flood prevention and mitigation have changed a lot.These changes are to shift the focus from flood control to flood risk management,in which the assessment of vulnerability to floods caused by each sector and field corresponding to each flood magnitude is typical.Current flood vulnerability assessment studies are basically holistic based on factors affected by floods or in aspects:economy,society and ecological environment,and aspects that are mentioned in all areas of social life.The content of the flood vulnerability assessment method usually considers 3 components:E(Exposure),S(Susceptibility),A(Adaptability-Recovery).Each component will contain many different variables belonging to different objects and different natural-economic-social characteristics in each area.Therefore,for each research area,the evaluation method needs to establish an appropriate set of indicators.A set of indicators used to assess flood vulnerability must:be scientific;be practical;simplify the investigation,collection and synthesis of data.This study has established a set of combinatorial indicators including 27 indicators for the T-BRB(Thach Han-Ben Hai River Basin)on the basis of analysis and synthesis from case studies. 展开更多
关键词 VULNERABILITY combine indicators T-BRB
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Comparative study of ancient and modern literature for Láogōng(劳宫PC8)in the indications and combination rules 被引量:1
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作者 Jie ZHANG Yong-zheng ZHU +2 位作者 Hong-Ling JIA Zhen-Ling ZHANG Yong-Chen ZHANG 《World Journal of Acupuncture-Moxibustion》 CSCD 2022年第2期168-177,共10页
Objective:To explore the clinical application rules of Láogōng(劳宫PC8)by analyzing the comparison and contrast of the practice with this acupoint in ancient times and in present.Methods:Relevant literature befo... Objective:To explore the clinical application rules of Láogōng(劳宫PC8)by analyzing the comparison and contrast of the practice with this acupoint in ancient times and in present.Methods:Relevant literature before October 1,1949 was selected from Chinese Medical Code(Fifth Edition)and Compilation of Moden Chinese Medicine Journals and literature published after October 1,1949 was screened from China National knowledge Infrastructure(CNIK),Wanfang Data Knowledge Service Platform(Wanfang),VIP Chinese Journal Service Platform(VIP),Chinese BioMedine Database(CBM),Pubmed Database,and Web of Science.After screening,SQL Server database was established.The complex network analysis was conducted by using Gephi and the cluster analysis was performed by SPSS Statistics.Results:Before October 1,1949,Lráogōng(劳宫PC8),on a single use or with a match of Dàlíng(大陵PC7),Guānyuán(关元CV4),and Zúsānlǐ(足三里ST36),was mainly used for treating ozostomia and edema due to pregnancy.However,Láogōng(劳宫PC8),on a single use or with a match of Yǒngquán(涌泉KI1),Hégǔ(合谷L14)and Nèiguān(内关PC6)was commonly for the treatment of toothache and the sequelae after wind stroke after October 1 st,1949.Conclusion:Láogōng(劳宫PC8)is mainly used to treat local disorders or diseases pertaining to the pericardium meridian.The single-point therapy was commonly applied before October 1 st,1949,while a combination of other points is more common afterwards and the scope of indication expands,with its application for psychiatry disorders,pain diseases and emergent diseases.Acupoints on the same meridian of Láogōng(劳宫PC8),ying-spring points,the back-shu points and combination between and the upper and the lower are dominated in the selection of supplementary points.The supplementary acupoints with the highest frequency of use were specific acupoints,including five-shu points,yuan-source points,front-mu points,etc。 展开更多
关键词 Láogōng(劳宫PC8) indicATIONS Acupoint combination Data mining
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Winter Wheat Yield Estimation Based on Sparrow Search Algorithm Combined with Random Forest:A Case Study in Henan Province,China 被引量:1
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作者 SHI Xiaoliang CHEN Jiajun +2 位作者 DING Hao YANG Yuanqi ZHANG Yan 《Chinese Geographical Science》 SCIE CSCD 2024年第2期342-356,共15页
Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous r... Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous research has paid relatively little attention to the interference of environmental factors and drought on the growth of winter wheat.Therefore,there is an urgent need for more effective methods to explore the inherent relationship between these factors and crop yield,making precise yield prediction increasingly important.This study was based on four type of indicators including meteorological,crop growth status,environmental,and drought index,from October 2003 to June 2019 in Henan Province as the basic data for predicting winter wheat yield.Using the sparrow search al-gorithm combined with random forest(SSA-RF)under different input indicators,accuracy of winter wheat yield estimation was calcu-lated.The estimation accuracy of SSA-RF was compared with partial least squares regression(PLSR),extreme gradient boosting(XG-Boost),and random forest(RF)models.Finally,the determined optimal yield estimation method was used to predict winter wheat yield in three typical years.Following are the findings:1)the SSA-RF demonstrates superior performance in estimating winter wheat yield compared to other algorithms.The best yield estimation method is achieved by four types indicators’composition with SSA-RF)(R^(2)=0.805,RRMSE=9.9%.2)Crops growth status and environmental indicators play significant roles in wheat yield estimation,accounting for 46%and 22%of the yield importance among all indicators,respectively.3)Selecting indicators from October to April of the follow-ing year yielded the highest accuracy in winter wheat yield estimation,with an R^(2)of 0.826 and an RMSE of 9.0%.Yield estimates can be completed two months before the winter wheat harvest in June.4)The predicted performance will be slightly affected by severe drought.Compared with severe drought year(2011)(R^(2)=0.680)and normal year(2017)(R^(2)=0.790),the SSA-RF model has higher prediction accuracy for wet year(2018)(R^(2)=0.820).This study could provide an innovative approach for remote sensing estimation of winter wheat yield.yield. 展开更多
关键词 winter wheat yield estimation sparrow search algorithm combined with random forest(SSA-RF) machine learning multi-source indicator optimal lead time Henan Province China
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Comprehensive Evaluation of Distributed PV Grid-Connected Based on Combined Weighting Weights and TOPSIS-RSR Method
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作者 Yue Yang Jiarui Zheng +2 位作者 Long Cheng Yongnan Zhu Hao Wu 《Energy Engineering》 EI 2024年第3期703-728,共26页
To effectively quantify the impact of distributed photovoltaic(PV)access on the distribution network,this paper proposes a comprehensive evaluation method of distributed PV grid connection combining subjective and obj... To effectively quantify the impact of distributed photovoltaic(PV)access on the distribution network,this paper proposes a comprehensive evaluation method of distributed PV grid connection combining subjective and objective combination of assignment and technique for order preference by similarity to an ideal solution(TOPSIS)—rank sum ratio(RSR)(TOPSIS-RSR)method.Based on the traditional distribution network evaluation system,a comprehensive evaluation system has been constructed.It fully considers the new development requirements of distributed PV access on the environmental friendliness and absorptive capacity of the distribution grid and comprehensively reflects the impact of distributed PV grid connection.The analytic hierarchy process(AHP)was used to determine the subjective weights of the primary indicators,and the Spearman consistency test was combined to determine the weights of the secondary indicators based on three objective assignment methods.The subjective and objective combination weights of each assessment indicator were calculated through the principle of minimum entropy.Calculate the distance between the indicators to be evaluated and the positive and negative ideal solutions,the relative closeness ranking,and qualitative binning by TOPSIS-RSR method to obtain the comprehensive evaluation results of different scenarios.By setting up different PV grid-connected scenarios and utilizing the IEEE33 node simulation algorithm,the correctness and effectiveness of the proposed subject-object combination assignment and integrated assessment method are verified. 展开更多
关键词 Distributed PV grid-connected comprehensive evaluation evaluation indicator system combined subjective and objective empowerment TOPSIS-RSR method
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肝豆状核变性患者心脏MRI异常的危险因素识别及早期诊断价值指标筛选
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作者 王娟 张杰 +2 位作者 张旭 束宏敏 杨任民 《中风与神经疾病杂志》 2026年第2期99-104,共6页
目的 通过心脏MRI(CMR)评估肝豆状核变性(又称Wilson病,WD)患者,探讨其心脏功能异常的危险因素,并筛选具有早期诊断价值的指标。方法 随机选择确诊WD的患者进行CMR检查,根据CMR检查结果分为异常组和正常组,先通过单因素分析筛选潜在危... 目的 通过心脏MRI(CMR)评估肝豆状核变性(又称Wilson病,WD)患者,探讨其心脏功能异常的危险因素,并筛选具有早期诊断价值的指标。方法 随机选择确诊WD的患者进行CMR检查,根据CMR检查结果分为异常组和正常组,先通过单因素分析筛选潜在危险因素,再对显著差异变量进行多因素Logistic回归分析,最后对筛查的独立危险因素进行ROC诊断分析。结果 共纳入42例WD患者,CMR异常组与正常组各21例。异常组年龄较大,且总胆红素、血清铜和治疗期间最高24 h尿铜水平均高于正常组,差异具有统计学意义。多因素Logistic回归分析显示白细胞计数(OR=2.927,95%CI 1.127~7.839,P=0.028)、血清铜(OR=3.822,95%CI 1.108~13.178,P=0.034)和Ⅳ型胶原(OR=1.097,95%CI 1.011~1.191,P=0.027)是WD患者CMR异常的独立危险因素。ROC分析表明,在单一指标中,血清铜的诊断效能最高(AUC=0.713),白细胞计数(AUC=0.651)和Ⅳ型胶原(AUC=0.644)次之且相近;三者联合模型的诊断效能显著提高(AUC=0.869)。结论 血清铜是诊断WD患者CMR异常的效能最高的单一指标,但血清铜、白细胞计数和Ⅳ型胶原三者联合指标在识别WD病患者心脏功能异常方面具有更优的诊断价值。 展开更多
关键词 肝豆状核变性 心脏MRI 血清铜 危险因素 联合指标
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基于组合权重—云模型的湖南省郴州市水安全评价
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作者 盛东 徐幸仪 +2 位作者 赵磊 徐蕾 王远坤 《水电能源科学》 北大核心 2026年第1期42-47,共6页
为弥补现有水安全评价方法在指标选择的科学性、权重分配的准确性方面的不足,围绕指标优选和权重赋值优化,构建了一套系统的水安全评价流程,从防洪、饮水、用水、河湖生态和社会经济安全五个方面出发,通过相关性分析、主成分分析和信息... 为弥补现有水安全评价方法在指标选择的科学性、权重分配的准确性方面的不足,围绕指标优选和权重赋值优化,构建了一套系统的水安全评价流程,从防洪、饮水、用水、河湖生态和社会经济安全五个方面出发,通过相关性分析、主成分分析和信息敏感性分析筛选关键指标,并结合熵权法、层次分析法、投影寻踪模型与云模型,利用模拟退火算法求解组合权重,最终采用云模型进行综合评价,并以湖南省郴州市为例进行分析。结果表明,指标优选筛选出了工业重复用水率、人均水资源占有量等22个关键指标;基于模拟退火算法求解的组合权重与指标信息敏感性的相关性最高(R^(2)=0.744 2),权重分配更加合理;郴州市2016~2022年水安全状态整体为“基本安全”,呈现持续改善趋势。研究结果验证了所构建模型的有效性和适用性,为城市水安全评价提供了新的方法论支持与实践指导。 展开更多
关键词 水安全 指标优选 模拟退火算法 组合权重 云模型 郴州市
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炎症指标与儿童支原体肺炎严重程度的关系及对合并细菌性感染的诊断效能分析
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作者 王刚 李维春 施大庆 《河北医学》 2026年第1期167-174,共8页
目的:探讨炎症指标对儿童支原体肺炎严重程度及合并细菌性感染的诊断价值。方法:回顾性选取2023年1月至2024年12月期间于医院收治的儿童支原体肺炎患者共105例作为研究对象。根据儿童支原体肺炎严重程度,将患者分为重症组(n=42)和轻症组... 目的:探讨炎症指标对儿童支原体肺炎严重程度及合并细菌性感染的诊断价值。方法:回顾性选取2023年1月至2024年12月期间于医院收治的儿童支原体肺炎患者共105例作为研究对象。根据儿童支原体肺炎严重程度,将患者分为重症组(n=42)和轻症组(n=63)。同时根据是否出现合并细菌性感染将重症组和轻症组的所有患者分为感染组(n=37)和非感染组(n=68)。收集患儿的临床资料以及实验室检查结果,通过单因素分析、相关性分析和多因素Logistic回归分析探讨儿童支原体肺炎严重程度的独立危险因素,并使用采用受试者工作特征曲线(ROC)评价炎症指标对合并细菌性感染联合诊断的效能。结果:儿童支原体肺炎严重程度影响因素的单因素分析结果提示,重症组和轻症组的炎症指标差异均有统计学意义(P<0.05),多因素Logistic回归分析结果显示,PCT和IL-6是评价儿童支原体肺炎严重程度的影响因素(P<0.05);儿童支原体肺炎合并细菌性感染的单因素分析结果提示,感染组与未感染组之间的炎症指标比较,差异均有统计学意义(均P<0.05)。儿童支原体肺炎合并细菌性感染影响因素的多因素Logistic回归分析结果显示,NLR、CRP、IL-6、LDH、WBC是评价儿童支原体肺炎合并细菌性感染的独立危险因素(P<0.05),绘制ROC曲线,结果显示,NLR、CRP、IL-6、LDH、WBC水平预测曲线下面积(AUC)分别为0.649、0.644、0.645、0.636、0.656,联合预测AUC为0.874,联合预测有较高的诊断价值。结论:炎症指标可以帮助医护人员诊断儿童支原体肺炎严重程度及是否合并细菌性感染,相比较单一指标,多个指标联用对对儿童支原体肺炎是否合并细菌性感染的诊断效能更高。 展开更多
关键词 支原体肺炎 炎症指标 儿童 合并细菌性感染
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基于改进变模态分解和宽核深度卷积神经网络的中介轴承故障诊断方法
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作者 田晶 谢肇阳 +1 位作者 吕静宜 林政 《推进技术》 北大核心 2026年第1期309-320,共12页
针对中介轴承受背景噪声干扰导致故障特征提取困难且诊断识别率低的问题,提出一种基于河马算法(Hippopotamus Optimization Algorithm,HO)改进变模态分解(Variational Mode Decomposition,VMD)、并结合第一层宽卷积核深度卷积神经网络(D... 针对中介轴承受背景噪声干扰导致故障特征提取困难且诊断识别率低的问题,提出一种基于河马算法(Hippopotamus Optimization Algorithm,HO)改进变模态分解(Variational Mode Decomposition,VMD)、并结合第一层宽卷积核深度卷积神经网络(Deep Convolutional Neural Networks with Wide First-layer Kernel,WDCNN)的故障诊断方法。该方法首先综合包络谱能量、峭度和排列熵构建多维度联合指标作为适应度函数,通过河马算法寻优确定VMD关键变量参数,其次,将原始信号分解后,根据相关系数-样本熵准则筛选有效模态分量进行重构,最后,将重构信号作为样本输入WDCNN模型完成故障诊断。凯斯西储大学轴承数据集试验结果表明:重构信号多次诊断的准确率为98.30%,相较于支持向量机、反向传播神经网络与一维卷积神经网络诊断有更高的正确率;对于自建中介轴承故障模拟试验台数据的多次诊断的平均准确率为96.4%,多种分类方法准确率平均优化了18.9%,稳定性优化了52%。证明该提方法能够去除噪声等非线性干扰成分,有效提升故障诊断模型分类准确性。 展开更多
关键词 中介轴承 多维度联合函数 河马算法 变模态分解 第一层宽卷积核深度卷积神经网络
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基于GRA-TOPSIS模型的宜水幸福河综合评价
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作者 刘聚涛 李孙鹏 +1 位作者 胡芳 刁造伟 《长江科学院院报》 北大核心 2026年第2期211-219,共9页
为构建适配江西省省情的幸福河湖评价体系,以江西省幸福河湖建设任务为基础框架,从平安、文明、健康、宜居、人文、富民六个维度提出幸福河湖内涵,并以此为理论支撑,构建江西省幸福河湖评价指标体系,构建基于灰色关联分析法(GRA)和优劣... 为构建适配江西省省情的幸福河湖评价体系,以江西省幸福河湖建设任务为基础框架,从平安、文明、健康、宜居、人文、富民六个维度提出幸福河湖内涵,并以此为理论支撑,构建江西省幸福河湖评价指标体系,构建基于灰色关联分析法(GRA)和优劣解距离法(TOPSIS)的综合评价模型,以宜水为研究案例,对2019—2023年宜水幸福等级开展动态评价,结合权重敏感性试验验证该评价体系的适用性。结果表明:2019—2023年间,宜水的综合相对贴近度分别为0.4189、0.4911、0.5473、0.6024、0.7136,年均增长率为14.04%,与2019年相比,2023年综合相对贴近度提升了1.7035倍,综合幸福等级从Ⅲ级合格水平提升至Ⅰ级优水平,说明宜水在幸福河湖规划建设推进过程中成效显著。从准则层指标来看,除“富民”呈波动态势外,其余准则层指标相对贴近度均保持逐年增长态势。“富民”是影响宜水幸福等级的主要方面,其中水资源开发利用率与万元GDP用水量为关键影响因子,未来宜水幸福河湖建设应重点强化节水管理、培育特色经济产业、深化跨区域协同治理等。权重敏感性试验结果验证了本研究构建的GRA-TOPSIS综合评价模型具有良好的适用性和科学性,研究成果可为江西省其他河湖的幸福河湖建设成效评估提供技术支撑与参考依据。 展开更多
关键词 幸福河湖评价 指标体系 GRA-TOPSIS综合评价模型 组合赋权 宜水 幸福河湖建设
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钢结构厚板焊接关键技术
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作者 范鹏涛 童林浪 贾宝华 《电焊机》 2026年第1期81-87,共7页
钢结构厚板焊接是大型工程建设的核心技术,直接决定结构安全与可靠性。我国自20世纪80年代起逐步突破厚板焊接技术瓶颈,国家体育场“鸟巢”相关焊接技术荣获国际权威奖项,标志着我国该领域技术已跻身国际领先水平。然而,当前行业内部分... 钢结构厚板焊接是大型工程建设的核心技术,直接决定结构安全与可靠性。我国自20世纪80年代起逐步突破厚板焊接技术瓶颈,国家体育场“鸟巢”相关焊接技术荣获国际权威奖项,标志着我国该领域技术已跻身国际领先水平。然而,当前行业内部分从业人员理论认知欠缺、技术应用不规范等问题,导致工程质量隐患与经济损失频发。基于焊接基础理论与工程实践,分析了钢结构厚板焊接机理,探讨了钢板和焊缝产生偏析的成因及其影响。重点讨论控制冷却速度(t_(8/5)(t_(8/3))、t_(100))对焊接接头性能的重要性,详细阐述多层多道错位焊接技术在减少偏析、控制线能量和提升焊接接头综合性能方面的优势,提出“打底焊(SMAW)-填充焊(GMAW)-盖面焊(FCAWG)”组合焊接工艺方案。研究成果为精准控制焊接缺陷、提升厚板焊接接头综合性能提供了理论依据与技术指导,对规范行业技术应用、降低工程损失具有重要实践价值。 展开更多
关键词 钢结构厚板焊接 偏析 控制指标 多层多道错位焊接 组合焊接工艺
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Evaluation of Farmland Drainage Water Quality by Fuzzy–Gray Combination Method 被引量:2
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作者 Xiaoling Wang Songmin Li +2 位作者 Yuling Yan Xiaotong Zheng Fuchao Zhang 《Transactions of Tianjin University》 EI CAS 2019年第1期91-100,共10页
The complex relationships between indicators and water conditions cause fuzzy and gray uncertainties in evaluation of water quality. Compared to conventional single-factor evaluation methods, the combination evaluatio... The complex relationships between indicators and water conditions cause fuzzy and gray uncertainties in evaluation of water quality. Compared to conventional single-factor evaluation methods, the combination evaluation method can consider these two uncertainties to produce more objective and reasonable evaluation results. In this paper, we propose a combination evaluation method with two main parts:(1) the use of fuzzy comprehensive evaluation and gray correlation analysis as submodels with which to consider the fuzzy and gray uncertainties and(2) the establishment of a combination model based on minimum bias squares. In addition, using this method, we evaluate the water quality of a ditch in a typical rice–wheat system of Yixing city in the Taihu Lake Basin during three rainfall events. The results show that the ditch water quality is not good and we found the chemical oxygen demand to be the key indicator that affects water quality most significantly. The proposed combination evaluation method is more accurate and practical than single-factor evaluation methods in that it considers the uncertainties of fuzziness and grayness. 展开更多
关键词 combination EVALUATION of water quality FUZZY comprehensive EVALUATION METHOD GRAY correlation analysis METHOD FARMLAND DITCH Key indicator
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基于Transformer-FNN和无人机高光谱遥感技术的棉花黄萎病危害等级分类研究 被引量:7
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作者 廖娟 梁业雄 +7 位作者 姜锐 邢赫 何欣颖 王辉 曾浩求 何松炜 唐赛欧 罗锡文 《农业机械学报》 北大核心 2025年第2期240-251,共12页
针对目前使用无人机识别棉花黄萎病危害等级时,光谱数据冗余度高和传统机器学习模型识别精度不足等问题,采用无人机搭载Nano-Hyperspec高光谱成像仪采集棉田高光谱图像,通过探究棉花冠层对不同黄萎病危害等级的光谱响应特征,利用最优植... 针对目前使用无人机识别棉花黄萎病危害等级时,光谱数据冗余度高和传统机器学习模型识别精度不足等问题,采用无人机搭载Nano-Hyperspec高光谱成像仪采集棉田高光谱图像,通过探究棉花冠层对不同黄萎病危害等级的光谱响应特征,利用最优植被指数组合建立一种适用于黄萎病危害等级分类的监测模型,实现棉花黄萎病危害等级的精准分类。首先,利用最小冗余最大相关算法(Minimum redundancy maximum relevance,mRMR)对17种潜在的植被指数和270个光谱波段进行特征重要性排序,将mRMR筛选得到的特征,通过逐步递增分组的方式输入至极限梯度提升模型(eXtreme gradient boosting,XGBoost),确定与黄萎病危害等级相关性最高的植被指数和光谱特征波段。然后,基于Transformer架构和前馈神经网络(Feedforward neural network,FNN)构建Transformer-FNN棉花黄萎病危害等级分类模型,将植被指数与光谱特征波段输入Transformer-FNN模型进行分类识别,对比了植被指数与光谱特征波段对棉花黄萎病危害等级分类识别的准确性。最后,利用后向传播神经网络(Back propagation neural network,BPNN)、Transformer和支持向量机(Support vector machine,SVM)构建棉花黄萎病危害等级分类模型,并对这4种分类模型进行精度验证与对比分析。结果表明:棉花黄萎病等级分类的最优植被指数组合为MSR和TVI,最优特征波段组合为430、439、488、566、697、722、742、764、769、782、822、831、858、873、878、893、909、985 nm。基于Transformer-FNN模型,植被指数对黄萎病危害等级的总体分类精度为95.6%,较光谱特征波段的总体分类精度89.4%提高6.2个百分点。基于植被指数,Transformer-FNN模型对黄萎病危害等级的分类识别率比BPNN模型提高11.2个百分点,比Transformer模型提高17.2个百分点,比SVM模型提高30.8个百分点。研究提出了一种通过植被指数进行棉花黄萎病高精度监测方法,可为大面积棉花黄萎病精确监测提供有效措施。 展开更多
关键词 棉花黄萎病 Transformer-FNN 特征组合 mRMR-XGBoost 高光谱遥感 植被指数
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基于组合赋权和物元可拓模型的东北河流健康评价 被引量:3
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作者 张媛媛 刘建卫 +1 位作者 逄晓腾 王明玮 《中国农村水利水电》 北大核心 2025年第2期31-36,44,共7页
为构建适用于东北地区的河流健康评价体系,针对东北河流特殊的季节性冰封水文特征,以及传统评价体系的应用局限性,如未给予水文指标合理的权重和解释,评价结果难以体现河流健康发展趋势等问题。基于《河湖健康评估技术导则(SL/T793-2020... 为构建适用于东北地区的河流健康评价体系,针对东北河流特殊的季节性冰封水文特征,以及传统评价体系的应用局限性,如未给予水文指标合理的权重和解释,评价结果难以体现河流健康发展趋势等问题。基于《河湖健康评估技术导则(SL/T793-2020)》,结合东北河流的水文、生态和社会服务功能等多维特征进行评价体系及方法改进,并以拉林河、第二松花江、伊通河、饮马河、东辽河等东北典型河流作为研究对象,通过采用组合赋权和物元可拓模型的方法,对各河流的健康等级进行量化评价,并利用综合关联度距离预测了河流健康水平的未来发展趋势。结果显示,改进后的东北河流健康评价体系共包含水文、水环境、河岸物理结构、水生生物以及社会服务功能5个状态层16项评价指标,能够基本适应东北河流的健康评价需求;健康评价结果得到伊通河最大综合关联度为0.014 6,健康等级为IV级,处于“不健康”状态,其余河流均处于“亚健康”状态(III级),且健康状态呈好转趋势。这一结论在综合指数法和模糊评价模型中得到了验证,能够为东北河流的持续健康管理提供科学依据,同时,也为类似寒冷地区的河流健康评估和管理提供了参考。 展开更多
关键词 河流健康 指标体系 组合赋权法 物元可拓
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益生菌联合制剂对产蛋后期蛋鸡产蛋性能、蛋品质及血清指标的影响 被引量:1
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作者 哈斯通拉嘎 席磊 +3 位作者 王金钰 张凡凡 聂芙蓉 赵金艳 《饲料工业》 北大核心 2025年第13期23-29,共7页
研究旨在探究地衣芽孢杆菌和前包被双歧杆菌联合制剂对产蛋后期蛋鸡生产性能、蛋品质及血清指标的影响。试验选用288只健康的63周龄海兰褐蛋鸡,随机分为4组,每组6个重复,每个重复12只鸡。对照组饲喂基础日粮,试验1、2、3组分别在基础日... 研究旨在探究地衣芽孢杆菌和前包被双歧杆菌联合制剂对产蛋后期蛋鸡生产性能、蛋品质及血清指标的影响。试验选用288只健康的63周龄海兰褐蛋鸡,随机分为4组,每组6个重复,每个重复12只鸡。对照组饲喂基础日粮,试验1、2、3组分别在基础日粮中添加1、2、3 kg/t的益生菌联合制剂,预试期7 d,正试期42 d。结果显示:①在生产性能方面,3个试验组次品蛋率均显著低于对照组(P<0.05),且各试验组之间差异显著(P<0.05),试验3组次品蛋率最低;试验2、3组料蛋比显著低于对照组(P<0.05)。②在蛋品质方面,试验3组蛋壳强度较对照组显著提高(P<0.05),试验2组和试验3组蛋黄色度较对照组显著改善(P<0.05)。③在血清指标方面,与对照组相比,试验2组和试验3组血清谷丙转氨酶(ALT)、碱性磷酸酶(AKP)水平显著提高(P<0.05);试验1组和试验3组血清谷草转氨酶(AST)水平显著提高(P<0.05);试验2组血清超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)水平均显著提高(P<0.05);各试验组丙二醛(MDA)含量均显著降低(P<0.05),试验1组最低;试验2组和试验3组白细胞介素-6(IL-6)水平显著提高(P<0.05),试验1组和试验2组肿瘤坏死因子-α(TNF-α)、免疫球蛋白M(IgM)水平显著提高(P<0.05);各试验组免疫球蛋白Y(IgY)水平均显著提高(P<0.05),试验1组增幅最大;试验2组和试验3组三碘甲状腺原氨酸(T3)水平显著高于对照组和试验1组(P<0.05),试验2组四碘甲状腺原氨酸(T4)水平显著高于对照组和其他两个试验组;试验1组雌二醇(E2)水平显著提高(P<0.05),试验3组则显著降低(P<0.05);试验2组卵泡生成素(FSH)水平显著高于对照组和其他两个试验组(P<0.05)。由此可见,地衣芽孢杆菌和前包被双歧杆菌联合制剂能够提高产蛋后期蛋鸡生产性能与蛋品质,并在提升机体抗氧化性能和免疫能力方面发挥积极作用。联合制剂添加量为2 kg/t时效果最佳。 展开更多
关键词 益生菌联合制剂 产蛋后期蛋鸡 生产性能 蛋品质 血清指标
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民航ADS-B数据多质量指标与多特征联合处理的GNSS干扰检测方法 被引量:1
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作者 陈敏 朱彤晖 +2 位作者 何炜琨 鲁建波 周洪 《交通运输工程学报》 北大核心 2025年第3期317-329,共13页
为解决导航卫星信号微弱,极易受到各种有意或无意的干扰,造成航空安全隐患、航班延误和运行效率下降的问题,利用全球导航卫星系统(GNSS)射频干扰导致的飞机航迹异常以及广播式自动相关监视(ADS-B)数据中导航质量指标的变化特性,在兼容DO... 为解决导航卫星信号微弱,极易受到各种有意或无意的干扰,造成航空安全隐患、航班延误和运行效率下降的问题,利用全球导航卫星系统(GNSS)射频干扰导致的飞机航迹异常以及广播式自动相关监视(ADS-B)数据中导航质量指标的变化特性,在兼容DO-260、DO-260A/B不同质量指标的情况下,给出了一种基于ADS-B数据多质量指标多特征联合处理的GNSS干扰检测方法;在GNSS干扰环境下提取ADS-B数据变化特征,通过检测导航质量指标的波动持续时间特征、质量指标变化同时航迹断裂特征以及多种质量指标同时下降特征等异常行为筛选出潜在干扰航班;对潜在航班进行干扰特征点提取,考虑到干扰航班在空间上具有聚集性,再利用MeanShift聚类方法实现了干扰航班的检测。试验结果表明:所提多质量指标多特征联合处理的GNSS干扰检测方法与单质量指标干扰检测方法相比精确率提高21.3%,能有效降低误检率,与熵权法相比查全率提高7%,在保证误检率不增加的前提下能有效降低漏检率,同时所提方法无需大量数据进行预训练,检测所需时间相比机器学习方法降低了98.4%,具有较好的实时性和工程应用价值,可为民用航空无线电干扰检测中的受干扰航班、受干扰时间和位置的确定提供解决方案。 展开更多
关键词 空中交通 ADS-B GNSS干扰 质量指标 航迹断裂 多特征联合处理
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SD大鼠慢性毒性与致癌合并试验血液指标正常值范围研究 被引量:1
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作者 曾丽海 陆丰荣 +3 位作者 殷霄 谢植伟 郑杰蔚 刘莉莉 《毒理学杂志》 2025年第4期279-287,294,共10页
目的探究SD大鼠慢性毒性与致癌合并试验血液指标正常值范围,建立本实验室的背景数据,为毒理学安全性评价提供参考。方法收集本实验室进行的11个慢性毒性与致癌合并试验的正常对照组血液常规和血清生化指标测定值,统计雌雄性大鼠在试验... 目的探究SD大鼠慢性毒性与致癌合并试验血液指标正常值范围,建立本实验室的背景数据,为毒理学安全性评价提供参考。方法收集本实验室进行的11个慢性毒性与致癌合并试验的正常对照组血液常规和血清生化指标测定值,统计雌雄性大鼠在试验第27、53、79和104周时,各指标的均值、标准差、95%置信区间和变异系数,并分析不同试验时间和不同性别之间的差异性。结果经过统计分析,得出雌雄性大鼠在试验第27、53、79和104周28项血液指标的均值、标准差、95%置信区间和变异系数。除LDH之外,其余所有检测指标在不同试验时间之间均存在一定差异性,且随着试验时间的增加,雌雄性大鼠有差异的指标个数逐渐增多。WBC、RBC、HGB、HCT、MCV、MCH、MCHC、RDW、PLT、AST、TP、ALB、白球比、BUN、CHOL、CREA、LDH和GLU等18项指标存在性别差异(P<0.05)。结论初步建立了本实验室SD大鼠慢性毒性与致癌合并试验血液指标的正常值范围,为毒理学安全性评价及其他类似研究提供参考。血液指标受试验时间和性别的影响,不同试验时间、不同性别分别建立背景数据对于试验结果的评价具有一定的指导意义。 展开更多
关键词 SD大鼠 慢性毒性与致癌合并试验 血液常规指标 血清生化指标 正常值范围
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数控机床精度保持性多指标综合评价方法
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作者 初红艳 李宁 +2 位作者 李迎 陈文涛 赵永胜 《机床与液压》 北大核心 2025年第13期30-38,共9页
精度保持性是制约国产数控机床走向高端的关键环节,精度保持性定量评价是数控机床综合性能提升的重要部分。针对现有评价方法不足,考虑机床精度指标在时间维度上的动态演变过程,提出一种数控机床精度保持性综合评价方法。采用精度寿命... 精度保持性是制约国产数控机床走向高端的关键环节,精度保持性定量评价是数控机床综合性能提升的重要部分。针对现有评价方法不足,考虑机床精度指标在时间维度上的动态演变过程,提出一种数控机床精度保持性综合评价方法。采用精度寿命、精度保持度、精度退化速率、精度波动度4个评价指标构建精度保持性多指标评价体系,基于层次分析法确定各评价指标初始权重,利用熵权法对初始权重进行修正,最终由组合赋权法得到各指标的综合权重,并结合评价指标数据计算精度保持性综合评价指数。通过一组算例数据对精度保持性综合评价方法有效性进行验证。在此基础上,对某型立式加工中心精度指标进行长期监测,按照所提方法计算关键精度指标的精度保持性综合评价指数,对比得出精度保持性水平高低并进行分析。结果表明:该方法利用4个指标对机床精度保持性进行评价,更加全面反映精度退化过程,实例分析某机床X向直线轴的Y向精度保持性高于Z向,与实际情况一致。 展开更多
关键词 数控机床 精度保持性 多指标综合评价 组合赋权
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