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Cartan-Eilenberg绝对clean和level复形研究
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作者 张丽英 《洛阳理工学院学报(自然科学版)》 2020年第2期89-93,共5页
本文给出了Cartan-Eilenberg绝对clean(Cartan-Eilenberg level)复形的若干等价刻画,并证明了Cartan-Eilenberg绝对clean(Cartan-Eilenberg level)复形的类关于直和、直积、直和项、正向极限、纯子复形、纯商复形封闭。特别地,若A是CE绝... 本文给出了Cartan-Eilenberg绝对clean(Cartan-Eilenberg level)复形的若干等价刻画,并证明了Cartan-Eilenberg绝对clean(Cartan-Eilenberg level)复形的类关于直和、直积、直和项、正向极限、纯子复形、纯商复形封闭。特别地,若A是CE绝对clean复形,则对于任意的n>0和任意的CE超有限表示复形X,有Extn(X,A)=0。 展开更多
关键词 绝对clean模 level cartan-eilenberg绝对clean复形 cartan-eilenberg level复形
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Malondialdehyde and superoxide dismutase levels of dogs with complex dermatitis after trigona honey therapy
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作者 Ni Luh Lasmi Purwanti I Nyoman Suartha +1 位作者 I Nyoman Suarsana Putu Devi Jayanti 《Infectious Diseases Research》 2022年第2期32-37,共6页
Dermatitis is a combination of various skin disease agents such as bacteria,fungi,ectoparasites,viruses and metabolic diseases with various clinical symptoms or signs.Dermatitis can cause an imbalance between ROS and ... Dermatitis is a combination of various skin disease agents such as bacteria,fungi,ectoparasites,viruses and metabolic diseases with various clinical symptoms or signs.Dermatitis can cause an imbalance between ROS and antioxidants.Exogenous antioxidants are needed to help balance antioxidant and ROS levels in the body by providing trigona honey.This study aims to determine the MDA and SOD levels of dogs with complex dermatitis after administration of trigona honey.This study used 12 dogs with complex dermatitis,with a moderate severity score.Dogs 4-6 months old.Samples were divided into control group(P0)without honey,fresh honey group(P1)5 mL/head/day and capsule honey group(P2)0.1 mg/head/day.Honey was given for 4 weeks in the treatment group.Examination of MDA and SOD levels was carried out using the ELISA kit.The results showed that the Trigona honey treatment had a significant effect(P<0.05)in reducing MDA levels and increasing SOD levels in dogs with complex dermatitis.Duncan's test results showed that SOD levels increased significantly at week 4,while week 2 and week 0 did not increase significantly.Trigona honey has anti-inflammatory,antibacterial,antiaging,antiulcer effects,helps in wound healing dermatitis and is an antioxidant.So that trigona honey can reduce plasma MDA levels and increase plasma SOD levels in dogs with complex dermatitis. 展开更多
关键词 MDA levels SOD levels complex dermatitis trigona honey
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Earthquake disaster chain model based on complex networks for urban engineering systems
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作者 Lu Zheng Yan Deyu Jiang Huanjun 《Journal of Southeast University(English Edition)》 EI CAS 2024年第3期230-237,共8页
According to news reports on severe earthquakes since 2008,a total of 51 cases with magnitudes of 6.0 or above were analyzed,and 14 frequently occurring secondary disasters were identified.A disaster chain model was d... According to news reports on severe earthquakes since 2008,a total of 51 cases with magnitudes of 6.0 or above were analyzed,and 14 frequently occurring secondary disasters were identified.A disaster chain model was developed using principles from complex network theory.The vulnerability and risk level of each edge in this model were calculated,and high-risk edges and disaster chains were identified.The analysis reveals that the edge“floods→building collapses”has the highest vulnerability.Implementing measures to mitigate this edge is crucial for delaying the spread of secondary disasters.The highest risk is associated with the edge“building collapses→casualties,”and increased risks are also identified for chains such as“earthquake→building collapses→casualties,”“earthquake→landslides and debris flows→dammed lakes,”and“dammed lakes→floods→building collapses.”Following an earthquake,the prompt implementation of measures is crucial to effectively disrupt these chains and minimize the damage from secondary disasters. 展开更多
关键词 EARTHQUAKE disaster chain seismic resilience secondary disaster complex network VULNERABILITY risk level
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Multilevel Modeling of Binary Outcomes with Three-Level Complex Health Survey Data
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作者 Shafquat Rozi Sadia Mahmud +2 位作者 Gillian Lancaster Wilbur Hadden Gregory Pappas 《Open Journal of Epidemiology》 2017年第1期27-43,共17页
Complex survey designs often involve unequal selection probabilities of clus-ters or units within clusters. When estimating models for complex survey data, scaled weights are incorporated into the likelihood, producin... Complex survey designs often involve unequal selection probabilities of clus-ters or units within clusters. When estimating models for complex survey data, scaled weights are incorporated into the likelihood, producing a pseudo likeli-hood. In a 3-level weighted analysis for a binary outcome, we implemented two methods for scaling the sampling weights in the National Health Survey of Pa-kistan (NHSP). For NHSP with health care utilization as a binary outcome we found age, gender, household (HH) goods, urban/rural status, community de-velopment index, province and marital status as significant predictors of health care utilization (p-value < 0.05). The variance of the random intercepts using scaling method 1 is estimated as 0.0961 (standard error 0.0339) for PSU level, and 0.2726 (standard error 0.0995) for household level respectively. Both esti-mates are significantly different from zero (p-value < 0.05) and indicate consid-erable heterogeneity in health care utilization with respect to households and PSUs. The results of the NHSP data analysis showed that all three analyses, weighted (two scaling methods) and un-weighted, converged to almost identical results with few exceptions. This may have occurred because of the large num-ber of 3rd and 2nd level clusters and relatively small ICC. We performed a sim-ulation study to assess the effect of varying prevalence and intra-class correla-tion coefficients (ICCs) on bias of fixed effect parameters and variance components of a multilevel pseudo maximum likelihood (weighted) analysis. The simulation results showed that the performance of the scaled weighted estimators is satisfactory for both scaling methods. Incorporating simulation into the analysis of complex multilevel surveys allows the integrity of the results to be tested and is recommended as good practice. 展开更多
关键词 HEALTH Care Utilization complex HEALTH SURVEY with Sampling WEIGHTS Simulations for complex SURVEY Pseudo LIKELIHOOD THREE-level Data
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基于梯度增量level-set方法的复杂物体入水砰击数值模拟
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作者 石伏龙 李洪鑫 +2 位作者 辛建建 袁琪 季孟洁 《船舶力学》 EI CSCD 北大核心 2024年第6期877-886,共10页
复杂结构物自由表面砰击问题,如空投鱼雷、水空无人航行器潜水和高速船出入水,一直是海洋工程领域的研究热点。本文采用梯度增量level-set和虚拟网格法数值模拟复杂结构物的入水砰击,采用时间半隐式有限差分法求解不可压缩Navier-Stoke... 复杂结构物自由表面砰击问题,如空投鱼雷、水空无人航行器潜水和高速船出入水,一直是海洋工程领域的研究热点。本文采用梯度增量level-set和虚拟网格法数值模拟复杂结构物的入水砰击,采用时间半隐式有限差分法求解不可压缩Navier-Stokes方程,虚拟网格法可重构复杂结构物界面插值模块并施加无滑移边界条件,梯度增量level-set法可捕捉非线性自由表面翻卷、射流等物理现象。基于以上方法模拟二维圆柱的常速入水砰击,并与试验和数值结果对比,验证本文数值方法的正确性。最后,数值模拟二维船型剖面和飞机剖面的入水砰击,分析了冲击压力、运动响应、压力分布和自由表面运动随入水角度的变化规律。同时,通过模拟可观察到复杂结构浸入水中后的流体分离、射流和小角度空气腔等典型砰击物理现象。 展开更多
关键词 虚拟网格 浸入边界法 levelset 砰击 复杂结构
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基于water-level调整的认知无线电传输速率计算算法
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作者 刘玉涛 谭学治 刘帅 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2010年第9期25-29,51,共6页
在瑞利衰落模型下,根据认知用户的效用函数,来解决认知无线电中的信道规划问题,进而得到认知用户的传输速率。当认知用户传输功率和比特误码率受限时,其最终效用仅与water-level有关,因此文中提出了一种基于water-level调整的功率分配... 在瑞利衰落模型下,根据认知用户的效用函数,来解决认知无线电中的信道规划问题,进而得到认知用户的传输速率。当认知用户传输功率和比特误码率受限时,其最终效用仅与water-level有关,因此文中提出了一种基于water-level调整的功率分配及算法,实现了认知无线电中载波及功率的合理分配,并得到了认知用户的传输速率.理论与仿真分析表明:该算法具有较低的运算复杂度和接近于最优算法的认知用户效用;调整因子仅与算法的收敛速度有关,而与用户总效用及信道的分配结果无关. 展开更多
关键词 认知无线电 效用函数 water-level调整 信道分配 算法复杂度
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依托性能化设计方法的复杂建筑结构设计研究
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作者 王志勇 《价值工程》 2025年第1期131-134,共4页
某复杂高层连体建筑其主要构成部分为框架-剪力墙和连续式桁架。针对这种连续式桁架结构的选择优化展开研究,并根据完整的连续体模型,对其进行小震弹性评估、中震性能测试以及大震动态弹塑性评估。本文通过对连体建筑的核心议题进行深... 某复杂高层连体建筑其主要构成部分为框架-剪力墙和连续式桁架。针对这种连续式桁架结构的选择优化展开研究,并根据完整的连续体模型,对其进行小震弹性评估、中震性能测试以及大震动态弹塑性评估。本文通过对连体建筑的核心议题进行深入研究,涉及主要构件与节点的布置、抗连续坍塌的能力,以及在强烈地震作用下建筑物的形态与受损状况。经过深入剖析,研究结果显示,复杂高层连体建筑架构布局适宜,主要构件与节点的布置已实现预期功能,同时具备抵抗连续坍塌的能力。 展开更多
关键词 复杂高层连体结构 结构设计 性能化设计
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Lipoprotein(a)and Benefit of PCSK9 Inhibition in Emergency Complex Higher-risk and Indicated Patients 被引量:1
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作者 Zhi-li JIN Tao HE +7 位作者 Li PENG Xiao-yan WU Di FAN Ming CHEN Yong-zhen FAN Yuan-lin GUO Zhi-bing LU Hai-rong WANG 《Current Medical Science》 SCIE CAS 2023年第6期1206-1212,共7页
Objective There is a large population of patients classified as complex higher-risk and indicated patients(CHIPs)in China with a poor prognosis.The treatment of these patients is complex and challenging,especially whe... Objective There is a large population of patients classified as complex higher-risk and indicated patients(CHIPs)in China with a poor prognosis.The treatment of these patients is complex and challenging,especially when acute cardiac events occur,such as acute coronary syndrome(ACS)or heart failure.Pharmacotherapy and some mechanical circulatory support(MCS)therapeutic devices can provide stable hemodynamic support for CHIPs-percutaneous coronary intervention(PCI).LDL-C is an important pathogenic factor in atherosclerosis,and the target of blood lipid control.Recent studies have revealed that lipoprotein(a)[Lp(a)],which is formed when a covalent bond between apolipoprotein(a)and apolipoprotein B-100 is made,produces an LDL-like particle.This particle is an independent risk factor for the development of atherosclerosis,and is closely correlated to stent thrombosis and restenosis.Furthermore,this requires active intervention.PCSK9 inhibitors have been used in lipid-lowering treatment,and preventing atherosclerosis.The present study explores the efficacy of PCSK9 inhibitors in CHIPs-ACS,and the association between the change in Lp(a)and survival after 2 years of follow-up.Methods The present real-world,prospective control study enrolled 321 CHIPs-ACS who underwent emergency PCI from August 2019 to November 2020,and these patients were followed up for 2 years.These patients were divided into two groups:PCSK9 group(n=161)given the combined PCSK9 inhibitor(140 mg of evolocumab every 2 weeks)and statins-based therapy,and SOC group(n=160)treated with statin-based lipid-lowering therapy alone.Then,the change in lipid index was measured,and the cardiovascular(CV)event recurrence rate was evaluated after one month and 2 years.Afterwards,the contribution of serum lipid parameters,especially the Lp(a)alteration,in patients with earlier initiation of the PCSK9 inhibitor to the CV outcome was analyzed.Results The LDL-C level was significantly reduced in both groups:52.3%in the PCSK9 group and 32.3%(P<0.001)in the SOC group.It is noteworthy that the Lp(a)level decreased by 13.2%in the PCSK9 group,but increased by 30.3%in the SOC group(P<0.001).Furthermore,the number of CV events was not significantly different between the PCSK9 and SOC groups after the 2-year follow-up period.In the PCSK9 group,the Lp(a)reduction was associated with the baseline Lp(a)levels of the patients(r2=−0.315,P<0.001).Moreover,the decrease in Lp(a)contributed to the decline in CV events in patients who received ACS CHIPs-PCI,and the decrease in Lp(a)level was independent of the LDL-C level reduction.Conclusion The early initiation of PCSK9 inhibitors can significantly reduce the LDL-C and Lp(a)levels in ACS CHIPs-PCI.However,further studies are needed to confirm whether PCSK9 inhibitors can reduce the incidence of CV disease in CHIPs. 展开更多
关键词 PCSK9 inhibitor complex higher-risk and indicated patients lipoprotein(a)level low-density lipoprotein cholesterol level 2-year cardiovascular event rate
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Selection of Measured Signals in the Navigation Measuring Complex 被引量:1
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作者 柯芳 Andrey PROLETARSKY Konstantin NEUSIPIN 《Journal of Measurement Science and Instrumentation》 CAS 2011年第4期346-348,共3页
To increase accuracy of navigation parameters,a perspective measuring complex with intellectual components is developed.Conception of synthesis optimal structure of the measuring complex is realized basing on a select... To increase accuracy of navigation parameters,a perspective measuring complex with intellectual components is developed.Conception of synthesis optimal structure of the measuring complex is realized basing on a selective method using principles of the functional systems.Selection of measured information is finished by original numeric criterion of observation level of state vector components.Prediction is realized by algorithm of self-organization that makes synthesis of the optimal complication.Therefore mechanism of self-regulation is realized and accuracy of the selective navigation complex is increased. 展开更多
关键词 selected navigation complex functional systems intellectual components observation level selforganiza tion
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Evolution of the Internet AS-level topology:From nodes and edges to components 被引量:2
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作者 Xiao Liu Jinfa Wang +1 位作者 Wei Jing Hai Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第12期200-210,共11页
Studying the topology of infrastructure communication networks(e.g., the Internet) has become a means to understand and develop complex systems. Therefore, investigating the evolution of Internet network topology migh... Studying the topology of infrastructure communication networks(e.g., the Internet) has become a means to understand and develop complex systems. Therefore, investigating the evolution of Internet network topology might elucidate disciplines governing the dynamic process of complex systems. It may also contribute to a more intelligent communication network framework based on its autonomous behavior. In this paper, the Internet Autonomous Systems(ASes) topology from 1998 to 2013 was studied by deconstructing and analysing topological entities on three different scales(i.e., nodes,edges and 3 network components: single-edge component M1, binary component M2 and triangle component M3). The results indicate that: a) 95% of the Internet edges are internal edges(as opposed to external and boundary edges); b) the Internet network consists mainly of internal components, particularly M2 internal components; c) in most cases, a node initially connects with multiple nodes to form an M2 component to take part in the network; d) the Internet network evolves to lower entropy. Furthermore, we find that, as a complex system, the evolution of the Internet exhibits a behavioral series,which is similar to the biological phenomena concerned with the study on metabolism and replication. To the best of our knowledge, this is the first study of the evolution of the Internet network through analysis of dynamic features of its nodes,edges and components, and therefore our study represents an innovative approach to the subject. 展开更多
关键词 complex system Internet AS-level topology EVOLUTION network component
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Top-level modeling theory of multi-discipline virtual prototype 被引量:2
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作者 Tingyu Lin Xudong Chai Bohu Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第3期425-437,共13页
Multi-disciplinary virtual prototypes of complex products are increasingly and widely used in modern advanced manufactur- ing. How to effectively address the problems of unified modeling, composition and reuse based o... Multi-disciplinary virtual prototypes of complex products are increasingly and widely used in modern advanced manufactur- ing. How to effectively address the problems of unified modeling, composition and reuse based on the multi-disciplinary heteroge- neous models has brought great challenges to the modeling and simulation (M&S) science and technology. This paper presents a top-level modeling theory based on the meta modeling framework (M2F) of the COllaborative SIMulation (COSlM) theory of virtual prototyping to solve the problems. Firstly the fundamental prin- ciples of the top-level modeling theory are decribed to expound the premise, assumptions, basic conventions and special require- ments in the description of complex heterogeneous systems. Next the formalized definitions for each factor in top level modeling are proposed and the hierarchical nature of them is illustrated. After demonstrating that they are self-closing, this paper divides the top- level modeling into two views, static structural graph and dynamic behavioral graph. Finally, a case study is discussed to demon- strate the feasibility of the theory. 展开更多
关键词 top-level modeling virtual prototype complex product multi-discipline modeling and simulation.
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Late Cryogenian glaciation in South Australia:Fluctuating ice margin and no extreme or rapid post-glacial sea-level rise
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作者 George E.Williams Victor A.Gostin 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1397-1408,共12页
Postulated extreme sea-level rise of up to 1-1.5 km with the late Cryogenian Ghaub deglaciation in Namibia is contentious,as is the great rapidity(<104 yr)of the sea-level rise.Such extreme glacioeustatic events,if... Postulated extreme sea-level rise of up to 1-1.5 km with the late Cryogenian Ghaub deglaciation in Namibia is contentious,as is the great rapidity(<104 yr)of the sea-level rise.Such extreme glacioeustatic events,if real,would have been global and affected all continents.In South Australia,up to six glacial advances and retreats during the late Cryogenian Elatina glaciation indicate a fluctuating ice margin.The latter stage of the Elatina glaciation and the immediate post-glacial environment are examined here for evidence of extreme and rapid sea-level rise.In the central Adelaide Rift Complex,diamictite with faceted and striated clasts occurs at the top of the Elatina Formation<1-2 m beneath the early Ediacaran Nuccaleena Formation’cap carbonate’.One hundred kilometres to the south,~30 m of siltstone and sandstone followed by^6 m of clast-poor diamictite with clasts 10+cm long occur between tidal rhythmites and the cap carbonate.Three hundred kilo metres further south,~70 m of siltsto ne,dolo mitic siltstone and minor dolomite separate tidal rhythmites and early Ediacaran strata.Hence the rhythmites were deposited during a high stand(interstadial or interglacial),not during post-glacial sea-level rise.Storm-generated erosional surfaces within tidal rhythmites at Warren Gorge indicate intermittent rhythmite deposition,and water depth and other palaeoenvironmental factors are uncertain,casting doubt on a published estimate of rapid sea-level rise during rhythmite deposition.The lack of late Cryogenian deeply incised valleys and thick valley-fill deposits in South Australia and central Australia argues against extreme sea-level variations.A hiatus occurred between Elatina deglaciation and deposition of the Nuccaleena cap carbonate,and three palaeomagnetic polarity chrons identified in the cap carbonate imply slow deposition spanning 10^5-10^6 yr.This is supported by independent evidence from magnetic chronostratigraphy for Ediacaran strata in South Australia and California,and by stratigraphic and sedimentological arguments for condensed deposition of cap carbonates.It is concluded that neither extreme nor rapid sea-level rise was associated with late Cryogenian deglaciation in South Australia. 展开更多
关键词 LATE CRYOGENIAN GLACIATION Sea level Adelaide RIFT complex Elatina FORMATION Nuccaleena FORMATION
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Synthesis, Characterization and Luminescence Properties of Rare Earth Complexes with Bis(Pyridinyl-Amide)
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作者 Chang Yuwei Yang Jingjun 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第2期181-181,共1页
A ligand, N^1, N^4-di ( pyridin-2-yl ) succi- namide (L) and its lanthanide( IH ) complexes (RE = La, Eu, Tb, Gd, Yb ) were synthesized and characterized in detail. The results indicate that the composition of... A ligand, N^1, N^4-di ( pyridin-2-yl ) succi- namide (L) and its lanthanide( IH ) complexes (RE = La, Eu, Tb, Gd, Yb ) were synthesized and characterized in detail. The results indicate that the composition of the binary complexes is determined as [ REL (H2O)2(NO3)2] NO3, that the complexes are 1 : 1 electrolytes in DMF, and that the Tb^3+ complex has brightly green fluorescence in a solid state. At the same time, the energy levels of the excited triplet states for the six ligands were determined to be 22989 -1 cm . The fact that the ligand sensitize Tb^3+ complexes was explained by the relative energy gap between the lowest triplet energy level of the ligand (T) and ^5Dj of Tb^3+ or Eu^3+ . When 2000 cm^-1 〈 △E(T-^5D4) 〈 3000 cm^-1, the luminescent intensity of the Tb^3+ complex is stronger. When 3000 cm^-1〈 △E (T-^5D1), the luminescent intensity of the Eu^3+ complex is weak- er or close to nil. This means that the triplet energy level of the ligand is a chief factor that dominates RE^3+ luminescence. 展开更多
关键词 triolet energy level phosphorescence spectra antenna effect rare earth complex
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Aggregation operators and CRITIC-VIKOR method for confidence complex q-rung orthopair normal fuzzy information and their applications
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作者 Tahir Mahmood Zeeshan Ali Muhammad Naeem 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第1期40-63,共24页
Supply chain management is an essential part of an organisation's sustainable programme.Understanding the concentration of natural environment,public,and economic influence and feasibility of your suppliers and pu... Supply chain management is an essential part of an organisation's sustainable programme.Understanding the concentration of natural environment,public,and economic influence and feasibility of your suppliers and purchasers is becoming progressively familiar as all industries are moving towards a massive sustainable potential.To handle such sort of developments in supply chain management the involvement of fuzzy settings and their generalisations is playing an important role.Keeping in mind this role,the aim of this study is to analyse the role and involvement of complex q-rung orthopair normal fuzzy(CQRONF)information in supply chain management.The major impact of this theory is to analyse the notion of confidence CQRONF weighted averaging,confidence CQRONF ordered weighted averaging,confidence CQRONF hybrid averaging,confidence CQRONF weighted geometric,confidence CQRONF ordered weighted geometric,confidence CQRONF hybrid geometric operators and try to diagnose various properties and results.Furthermore,with the help of the CRITIC and VIKOR models,we diagnosed the novel theory of the CQRONF-CRITIC-VIKOR model to check the sensitivity analysis of the initiated method.Moreover,in the availability of diagnosed operators,we constructed a multi-attribute decision-making tool for finding a beneficial sustainable supplier to handle complex dilemmas.Finally,the initiated operator's efficiency is proved by comparative analysis. 展开更多
关键词 averaging/geometric aggregation operators complex q-rung orthopair normal fuzzy information confidence levels strategic decision-making methods
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句法复杂度与日语母语者汉语应用文写作质量关系研究 被引量:1
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作者 李杰 李颐蕾 《现代语文》 2024年第5期38-45,共8页
以中高级水平日语母语者所写的汉语应用文(求职信)为研究对象,在句层面和短语层面分别设立3个测量指标,考察不同层面的句法复杂度指标与写作质量的关系。研究发现,句层面的3项话题链指标与写作成绩相关均不显著。在短语层面,复杂名词短... 以中高级水平日语母语者所写的汉语应用文(求职信)为研究对象,在句层面和短语层面分别设立3个测量指标,考察不同层面的句法复杂度指标与写作质量的关系。研究发现,句层面的3项话题链指标与写作成绩相关均不显著。在短语层面,复杂名词短语的总数、长度指标与成绩相关不显著,而比率指标与成绩显著相关,能够解释应用文成绩总变异的17.7%,达到中等效应量。这一结论证明了短语层面的复杂名词短语比率是预测应用文写作成绩的有效指标。 展开更多
关键词 句法复杂度 写作质量 句层面指标 短语层面指标 复杂名词短语 应用文
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基于强化学习的离散层级萤火虫算法检测蛋白质复合物
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作者 张其文 郭欣欣 《计算机应用研究》 CSCD 北大核心 2024年第7期1977-1982,共6页
蛋白质复合物的检测有助于从分子水平上理解生命的活动过程。针对群智能算法检测蛋白质复合物时假阳/阴性率高、准确率低、种群多样性下降等问题,提出了基于强化学习的离散层级萤火虫算法检测蛋白质复合物(reinforcement learning-based... 蛋白质复合物的检测有助于从分子水平上理解生命的活动过程。针对群智能算法检测蛋白质复合物时假阳/阴性率高、准确率低、种群多样性下降等问题,提出了基于强化学习的离散层级萤火虫算法检测蛋白质复合物(reinforcement learning-based discrete level firefly algorithm for detecting protein complexes,RLDLFA-DPC)。引入强化学习思想提出一种自适应层级划分策略,动态调整层级结构,能有效解决迭代后期种群多样性下降的问题。在层级学习策略中个体向两个优秀层级学习,避免算法陷入局部最优。为了提高蛋白质复合物检测的精度,结合个体环境信息提出自适应搜索半径的局部搜索策略。最后,在酵母蛋白质的4个数据集上,与8种经典的蛋白质复合物检测方法进行对比,验证了该方法的有效性。 展开更多
关键词 蛋白质复合物 萤火虫算法 强化学习 层级学习策略 局部搜索策略
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明代府州县的繁简与等级划分——以江西为中心的考察
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作者 高寿仙 《史学集刊》 CSSCI 北大核心 2024年第3期19-34,共16页
从秦汉到元朝,皆以户口数量为主要指标,兼顾政治地位、地理位置、经济水平等因素,把地方政区划分为若干等级。明太祖一改前代做法,先是以税粮为标准把府州县分为上中下三等,旋即又综合考虑税粮多少以及地理冲僻、事务繁简、负担轻重等... 从秦汉到元朝,皆以户口数量为主要指标,兼顾政治地位、地理位置、经济水平等因素,把地方政区划分为若干等级。明太祖一改前代做法,先是以税粮为标准把府州县分为上中下三等,旋即又综合考虑税粮多少以及地理冲僻、事务繁简、负担轻重等因素把府州县分为繁简两等,开启了主要依照事务繁简和地理冲僻等因素划分政区等第的新趋向。到明代后期,繁简两分法被进一步发展为上中下三等制。从江西各府州县的相关资料看,上、中、下等级与政务繁简、道里冲僻、治理难易等因素之间具有一定的对应关系,但这种对应并不严格,说明政区等级评定是个非常复杂的问题,无论采用何种标准都难全部适用。 展开更多
关键词 明代 政区分等 繁简制 三等制
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全球价值链嵌入对农产品出口技术复杂度的影响
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作者 李秀香 黄伟凤 《技术经济与管理研究》 北大核心 2024年第5期38-43,共6页
选取2000—2019年74个国家或地区的面板数据,引入研发水平和人力资本作为中介变量,利用系统GMM两步法研究了农业全球价值链参与度对农产品出口技术复杂度的影响。研究发现,全球价值链前向和后向嵌入对农产品出口技术复杂度均产生了显著... 选取2000—2019年74个国家或地区的面板数据,引入研发水平和人力资本作为中介变量,利用系统GMM两步法研究了农业全球价值链参与度对农产品出口技术复杂度的影响。研究发现,全球价值链前向和后向嵌入对农产品出口技术复杂度均产生了显著正向影响,研发水平和人力资本在全球价值链嵌入对农产品出口技术复杂度的影响中存在中介作用,经济发展水平和土地资源对农产品出口技术复杂度有正向影响,而汇率水平和外商直接投资则对其产生了负向影响。因此,我国农业部门应积极参与全球价值链分工,加强农业技术创新和人力资本提升,但也需谨慎应对汇率波动引发的不确定性,以及外商直接投资可能导致的“低端锁定”问题。 展开更多
关键词 农业全球价值链 农产品出口技术复杂度 人力资本 研发水平
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结合邻居影响和资源分配的链路预测算法 被引量:1
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作者 刘英杰 刘士虎 +1 位作者 高海燕 徐伟华 《郑州大学学报(理学版)》 CAS 北大核心 2024年第1期53-59,共7页
传统的资源分配算法在进行链路预测时只考虑了共同邻居对资源分配的影响,却忽略了两个节点之间的二级节点对资源分配的影响。为了探究共同邻居和二级节点对预测两个节点之间连边存在可能性的影响,提出了一种结合邻居影响和资源分配的链... 传统的资源分配算法在进行链路预测时只考虑了共同邻居对资源分配的影响,却忽略了两个节点之间的二级节点对资源分配的影响。为了探究共同邻居和二级节点对预测两个节点之间连边存在可能性的影响,提出了一种结合邻居影响和资源分配的链路预测算法。实验结果表明,在多数网络中若两个节点接收更多由共同邻居分配给它们的资源,则可以提升预测它们之间连边存在可能性的准确率。在四个生态网络和一些平均聚类系数较低的网络中,若两个节点接收更多通过二级节点分配给它们的资源,则可以提升预测它们之间连边存在可能性的准确率。 展开更多
关键词 共同邻居 复杂网络 资源分配 资源传输 链路预测 二级节点
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城市地下空间地质安全多级变模糊变权综合评价法 被引量:2
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作者 刘洪华 王忠胜 +2 位作者 耿林 赵玉婷 陈闫 《安全与环境学报》 CAS CSCD 北大核心 2024年第1期19-32,共14页
城市地下空间地质安全评价可为城市地下空间规划和工程建设提供重要决策支持。城市地下空间地质安全评价问题是一个十分复杂的系统综合评价问题。目前常用的评价方法主要有层次分析法、模糊综合评价法、灰色关联度法、可拓物元法等,模... 城市地下空间地质安全评价可为城市地下空间规划和工程建设提供重要决策支持。城市地下空间地质安全评价问题是一个十分复杂的系统综合评价问题。目前常用的评价方法主要有层次分析法、模糊综合评价法、灰色关联度法、可拓物元法等,模糊综合评价法是其中应用效果最好、最广泛的方法。但目前常用的评价方法都属于常权综合评价法,且评价模型普遍采用加权平均模型,导致评价结果易受平均效应影响,并不适合复杂的非线性系统评价。将模糊集理论、可变模糊集理论及变权理论三者融合,提出了多级变模糊变权综合评价法,该方法的综合评价模型更加完善,适应能力更强。在理论上,通过修改综合评价模型,所提出的算法就可以退化为常用的模糊类方法,如模糊综合评价法、模糊变权综合评价法、可变模糊综合评价法。以青岛市红岛区的城市地下空间地质安全性评价为例,通过对比分析4种不同评价方法的评价结果,验证了所提方法的先进性及应用效果。多级变模糊变权综合评价法是一种多理论集成的综合评价方法。与各种常用的综合评价方法相比,该方法更加适用于城市地下空间地质安全评价及其他复杂系统的综合评价。 展开更多
关键词 安全工程 地质安全性评价 复杂系统评价 城市地下空间 多级变模糊变权 综合评价模型
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