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Beyond statistical significance:Embracing minimal clinically important difference for better patient care
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作者 Naveen Jeyaraman Madhan Jeyaraman +2 位作者 Swaminathan Ramasubramanian Sangeetha Balaji Sathish Muthu 《World Journal of Methodology》 2025年第1期33-41,共9页
The minimal clinically important difference(MCID)represents a pivotal metric in bridging the gap between statistical significance and clinical relevance,addressing the direct impact of medical interventions from the p... The minimal clinically important difference(MCID)represents a pivotal metric in bridging the gap between statistical significance and clinical relevance,addressing the direct impact of medical interventions from the patient's perspective.This comprehensive review analyzes the evolution,applications,and challenges of MCID across medical specialties,emphasizing its necessity in ensuring that clinical outcomes not only demonstrate statistical significance but also offer genuine clinical utility that aligns with patient expectations and needs.We discuss the evolution of MCID since its inception in the 1980s,its current applications across various medical specialties,and the methodologies used in its calculation,highlighting both anchor-based and distribution-based approaches.Furthermore,the paper delves into the challenges associated with the application of MCID,such as methodological variability and the interpretation difficulties that arise in clinical settings.Recommendations for the future include standardizing MCID calculation methods,enhancing patient involvement in setting MCID thresholds,and extending research to incorporate diverse global perspectives.These steps are critical to refining the role of MCID in patient-centered healthcare,addressing existing gaps in methodology and interpretation,and ensuring that medical interventions lead to significant,patient-perceived improvements. 展开更多
关键词 Minimal clinically important difference Patient-centered care Clinical relevance Global health
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Portal vein pulsatility:An important sonographic tool assessment of systemic congestion for critical ill patients 被引量:1
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作者 Stavros Dimopoulos Michael Antonopoulos 《World Journal of Cardiology》 2024年第5期221-225,共5页
In this editorial we comment on the article by Kuwahara et al,published in the recent issue of the World Journal of Cardiology.In this interesting paper,the authors showed a correlation between portal vein pulsatility... In this editorial we comment on the article by Kuwahara et al,published in the recent issue of the World Journal of Cardiology.In this interesting paper,the authors showed a correlation between portal vein pulsatility ratio,examined by bedside ultrasonography,and prognosis of hospitalized patients with acute heart failure.Systemic congestion is being notoriously underdetected in the acutely ill population with conventional methods like clinical examination,biomarkers,central venous pressure estimation and X-rays.However,congestion should be a key therapeutic target due to its deleterious effects to end organ function and subsequently patient prognosis.Doppler flow assessment of the abdominal veins is gaining popularity worldwide,as a valuable tool in estimating comprehensively congestion and giving a further insight into hemodynamics and patient management. 展开更多
关键词 Systemic congestion Organ perfusion Hemodynamics Central venous pressure Point of care ultrasound Venous excess ultrasound
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Coexistence of Dirac and Weyl points in non-centrosymmetric semimetal NbIrTe_(4)
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作者 刘清馨 付阳 +4 位作者 丁鹏飞 马欢 郭朋杰 雷和畅 王善才 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期146-151,共6页
Using angle-resolved photoemission spectroscopy and density functional theory calculations methods,we investigate the electronic structures and topological properties of ternary tellurides NbIrTe_(4),a candidate for t... Using angle-resolved photoemission spectroscopy and density functional theory calculations methods,we investigate the electronic structures and topological properties of ternary tellurides NbIrTe_(4),a candidate for type-II Weyl semimetal.We demonstrate the presence of several Fermi arcs connecting their corresponding Weyl points on both termination surfaces of the topological material.Our analysis reveals the existence of Dirac points,in addition to Weyl points,giving both theoretical and experimental evidences of the coexistence of Dirac and Weyl points in a single material.These findings not only confirm NbIrTe_(4) as a unique topological semimetal but also open avenues for exploring novel electronic devices based on its coexisting Dirac and Weyl fermions. 展开更多
关键词 Fermi arc Weyl point Dirac point angle-resolved photoemission spectroscopy
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Exceptional points and quantum dynamics in a non-Hermitian two-qubit system
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作者 张益玺 张振涛 +2 位作者 杨震山 魏晓志 梁宝龙 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期212-218,共7页
We study the exceptional-point(EP) structure and the associated quantum dynamics in a system consisting of a non-Hermitian qubit and a Hermitian qubit. We find that the system possesses two sets of EPs, which divide t... We study the exceptional-point(EP) structure and the associated quantum dynamics in a system consisting of a non-Hermitian qubit and a Hermitian qubit. We find that the system possesses two sets of EPs, which divide the systemparameter space into PT-symmetry unbroken, partially broken and fully broken regimes, each with distinct quantumdynamics characteristics. Particularly, in the partially broken regime, while the PT-symmetry is generally broken in the whole four-dimensional Hilbert space, it is preserved in a two-dimensional subspace such that the quantum dynamics in the subspace are similar to those in the PT-symmetry unbroken regime. In addition, we reveal that the competition between the inter-qubit coupling and the intra-qubit driving gives rise to a complex pattern in the EP variation with system parameters. 展开更多
关键词 non-Hermitian system exceptional point PT-SYMMETRY
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Identification of Important FPGA Modules Based on Complex Network
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作者 Senjie Zhang Jinbo Wang +3 位作者 Shan Zhou Jingpei Wang Zhenyong Zhang Ruixue Wang 《Computers, Materials & Continua》 SCIE EI 2024年第1期1027-1047,共21页
The globalization of hardware designs and supply chains,as well as the integration of third-party intellectual property(IP)cores,has led to an increased focus from malicious attackers on computing hardware.However,exi... The globalization of hardware designs and supply chains,as well as the integration of third-party intellectual property(IP)cores,has led to an increased focus from malicious attackers on computing hardware.However,existing defense or detection approaches often require additional circuitry to perform security verification,and are thus constrained by time and resource limitations.Considering the scale of actual engineering tasks and tight project schedules,it is usually difficult to implement designs for all modules in field programmable gate array(FPGA)circuits.Some studies have pointed out that the failure of key modules tends to cause greater damage to the network.Therefore,under limited conditions,priority protection designs need to be made on key modules to improve protection efficiency.We have conducted research on FPGA designs including single FPGA systems and multi-FPGA systems,to identify key modules in FPGA systems.For the single FPGA designs,considering the topological structure,network characteristics,and directionality of FPGA designs,we propose a node importance evaluationmethod based on the technique for order preference by similarity to an ideal solution(TOPSIS)method.Then,for the multi-FPGA designs,considering the influence of nodes in intra-layer and inter-layers,they are constructed into the interdependent network,and we propose a method based on connection strength to identify the important modules.Finally,we conduct empirical research using actual FPGA designs as examples.The results indicate that compared to other traditional indexes,node importance indexes proposed for different designs can better characterize the importance of nodes. 展开更多
关键词 Hardware security FPGA circuits node importance interdependent network
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Melting points of ionic liquids:Review and evaluation
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作者 Zhengxing Dai Lei Wang +1 位作者 Xiaohua Lu Xiaoyan Ji 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第12期1802-1811,共10页
The melting points of ionic liquids(ILs)reported since 2020 were surveyed,collected,and reviewed,which were further combined with the previous data to provide a database with 3129 ILs ranging from 177.15 to 645.9 K in... The melting points of ionic liquids(ILs)reported since 2020 were surveyed,collected,and reviewed,which were further combined with the previous data to provide a database with 3129 ILs ranging from 177.15 to 645.9 K in melting points.In addition,the factors that affect the melting point of ILs from macro,micro,and thermodynamic perspectives were summarized and analyzed.Then the development of the quantitative structure-property relationship(QSPR),group contribution method(GCM),and conductor-like screening model for realistic solvents(COSMO-RS)for predicting the melting points of ILs were reviewed and further analyzed.Combined with the evaluation together with the preliminary study conducted in this work,it shows that COSMO-RS is more promising and possible to further improve its performance,and a framework was thus proposed. 展开更多
关键词 Ionic liquids Melting point COSMO-RS QSPR GCM
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Prediction of collapse process and tipping points for mutualistic and competitive networks with k-core method
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作者 段东立 毕菲菲 +3 位作者 李思凡 吴成星 吕长春 蔡志强 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期173-180,共8页
Ecosystems generally have the self-adapting ability to resist various external pressures or disturbances,which is always called resilience.However,once the external disturbances exceed the tipping points of the system... Ecosystems generally have the self-adapting ability to resist various external pressures or disturbances,which is always called resilience.However,once the external disturbances exceed the tipping points of the system resilience,the consequences would be catastrophic,and eventually lead the ecosystem to complete collapse.We capture the collapse process of ecosystems represented by plant-pollinator networks with the k-core nested structural method,and find that a sufficiently weak interaction strength or a sufficiently large competition weight can cause the structure of the ecosystem to collapse from its smallest k-core towards its largest k-core.Then we give the tipping points of structure and dynamic collapse of the entire system from the one-dimensional dynamic function of the ecosystem.Our work provides an intuitive and precise description of the dynamic process of ecosystem collapse under multiple interactions,and provides theoretical insights into further avoiding the occurrence of ecosystem collapse. 展开更多
关键词 complex networks tipping points dimension reduction k-core
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Triple points and phase transitions of D-dimensional dyonic Ad S black holes with quasitopological electromagnetism in Einstein–Gauss–Bonnet gravity
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作者 牟平辉 蒋青权 +1 位作者 何柯腱 李国平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期272-287,共16页
By considering the negative cosmological constant Λ as a thermodynamic pressure, we study the thermodynamics and phase transitions of the D-dimensional dyonic Ad S black holes(BHs) with quasitopological electromagnet... By considering the negative cosmological constant Λ as a thermodynamic pressure, we study the thermodynamics and phase transitions of the D-dimensional dyonic Ad S black holes(BHs) with quasitopological electromagnetism in Einstein–Gauss–Bonnet(EGB) gravity. The results indicate that the small/large BH phase transition that is similar to the van der Waals(vdW) liquid/gas phase transition always exists for any spacetime dimensions. Interestingly, we then find that this BH system exhibits a more complex phase structure in 6-dimensional case that is missed in other dimensions.Specifically, it shows for D = 6 that we observed the small/intermediate/large BH phase transitions in a specific parameter region with the triple point naturally appeared. Moreover, when the magnetic charge turned off, we still observed the small/intermediate/large BH phase transitions and triple point only in 6-dimensional spacetime, which is consistent with the previous results. However, for the dyonic Ad S BHs with quasitopological electromagnetism in Einstein–Born–Infeld(EBI) gravity, the novel phase structure composed of two separate coexistence curves observed by Li et al. [Phys. Rev. D105 104048(2022)] disappeared in EGB gravity. This implies that this novel phase structure is closely related to gravity theories, and seems to have nothing to do with the effect of quasitopological electromagnetism. In addition, it is also true that the critical exponents calculated near the critical points possess identical values as mean field theory. Finally, we conclude that these findings shall provide some deep insights into the intriguing thermodynamic properties of the dyonic Ad S BHs with quasitopological electromagnetism in EGB gravity. 展开更多
关键词 AdS black hole phase transition triple point
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Petrophysical Evaluation of Cape Three Points Reservoirs
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作者 Striggner Bedu-Addo Sylvester Kojo Danuor Larry Pax Chegbeleh 《International Journal of Geosciences》 CAS 2024年第2期162-179,共18页
The findings of a study to ascertain and assess the petrophysical characteristics of Cape Three Points reservoirs in the Western basin with a view to describe the reservoir quantitatively using Well Logs, Petrel and T... The findings of a study to ascertain and assess the petrophysical characteristics of Cape Three Points reservoirs in the Western basin with a view to describe the reservoir quantitatively using Well Logs, Petrel and Techlog. The investigated characteristics, which were all deduced from geophysical wire-line logs, include lithology, porosity, permeability, fluid saturation, and net to gross thickness. To characterise the reservoir on the field, a suite of wire-line logs including gamma ray, resistivity, spontaneous potential, and density logs for three wells (WELL_1X, WELL_2X, and WELL_3X) from the Tano Cape Three Point basin were studied. The analyses that were done included lithology delineation, reservoir identification, and petrophysical parameter determination for the identified reservoirs. The tops and bases of the three wells analysed were marked at a depth of 1203.06 - 2015.64 m, 3863.03 - 4253.85 m and 2497.38 - 2560.32 m respectively. There were no hydrocarbons in the reservoirs from the studies. The petrophysical parameters computed for each reservoir provided porosities of 13%, 3% and 11% respectively. The water saturation also determined for these three wells (WELL_1X, WELL_2X and WELL_3X) were 94%, 95% and 89% respectively. These results together with the behaviour of the density and neutron logs suggested that these wells are wildcat wells. 展开更多
关键词 Petrophysical Cape Three points RESERVOIRS
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Quantitative determination of the critical points of Mott metal–insulator transition in strongly correlated systems
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作者 牛月坤 倪煜 +4 位作者 王建利 陈雷鸣 邢晔 宋筠 冯世平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期647-652,共6页
Mottness is at the heart of the essential physics in a strongly correlated system as many novel quantum phenomena occur in the metallic phase near the Mott metal–insulator transition. We investigate the Mott transiti... Mottness is at the heart of the essential physics in a strongly correlated system as many novel quantum phenomena occur in the metallic phase near the Mott metal–insulator transition. We investigate the Mott transition in a Hubbard model by using the dynamical mean-field theory and introduce the local quantum state fidelity to depict the Mott metal–insulator transition. The local quantum state fidelity provides a convenient approach to determining the critical point of the Mott transition. Additionally, it presents a consistent description of the two distinct forms of the Mott transition points. 展开更多
关键词 critical point metal–insulator transition local quantum state fidelity strongly correlated system quasiparticle coherent weight
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Analysis of the inflection points of height-diameter models
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作者 Tzeng Yih Lam Mark J.Ducey 《Forest Ecosystems》 SCIE CSCD 2024年第4期414-422,共9页
The inflection point is an important feature of sigmoidal height-diameter(H-D)models.It is often cited as one of the properties favoring sigmoidal model forms.However,there are very few studies analyzing the inflectio... The inflection point is an important feature of sigmoidal height-diameter(H-D)models.It is often cited as one of the properties favoring sigmoidal model forms.However,there are very few studies analyzing the inflection points of H-D models.The goals of this study were to theoretically and empirically examine the behaviors of inflection points of six common H-D models with a regional dataset.The six models were the Wykoff(WYK),Schumacher(SCH),Curtis(CUR),HossfeldⅣ(HOS),von Bertalanffy-Richards(VBR),and Gompertz(GPZ)models.The models were first fitted in their base forms with tree species as random effects and were then expanded to include functional traits and spatial distribution.The distributions of the estimated inflection points were similar between the two-parameter models WYK,SCH,and CUR,but were different between the threeparameter models HOS,VBR,and GPZ.GPZ produced some of the largest inflection points.HOS and VBR produced concave H-D curves without inflection points for 12.7%and 39.7%of the tree species.Evergreen species or decreasing shade tolerance resulted in larger inflection points.The trends in the estimated inflection points of HOS and VBR were entirely opposite across the landscape.Furthermore,HOS could produce concave H-D curves for portions of the landscape.Based on the studied behaviors,the choice between two-parameter models may not matter.We recommend comparing seve ral three-parameter model forms for consistency in estimated inflection points before deciding on one.Believing sigmoidal models to have inflection points does not necessarily mean that they will produce fitted curves with one.Our study highlights the need to integrate analysis of inflection points into modeling H-D relationships. 展开更多
关键词 CONCAVITY Forest inventory and analysis Generalized height-diameter models Growth functions Height-diameter functions Mixed-effects modeling points of inflection Species-specific models
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An Analysis of Innovative Contributions to the Important Discourse on the Development of New Quality Productivity
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作者 Yao Hao Jie Wu 《Journal of Contemporary Educational Research》 2024年第6期135-141,共7页
The discourse on developing high-quality productivity marks a significant theoretical innovation,which is conducive to the modernization and sinicization of Marxism.It refines our understanding of“new quality product... The discourse on developing high-quality productivity marks a significant theoretical innovation,which is conducive to the modernization and sinicization of Marxism.It refines our understanding of“new quality productivity,”defining it as an advanced form driven by innovation,embodying“high technology,efficiency,and quality,”with the aim of comprehensively enhancing productivity.It elucidates the necessity of cultivating such forces,asserting that they are crucial for achieving high-quality development,securing a leading position in global technology,and fulfilling the aspirations for a better life.Moreover,it outlines a new implementation route,emphasizing strategies such as fostering technological autonomy,nurturing emerging industries,integrating education and talent in technology,adopting a“build through challenges”approach,adjusting solutions locally,and providing categorized guidance,all of which are based on the ongoing comprehensive reforms. 展开更多
关键词 New quality productivity Basic connotation important discourse Realistic approach Innovative contributions
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Analysis of the Significance of Key Points of Patient Interventional Psychological Care and Pain Care
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作者 Xiaoping Dai Chu Luo Jiawei Dai 《Journal of Clinical and Nursing Research》 2024年第3期66-71,共6页
Interventional therapy has become increasingly popular in clinical practice due to advancements in medical technology.However,patients often experience psychological and physiological pressure due to its invasive natu... Interventional therapy has become increasingly popular in clinical practice due to advancements in medical technology.However,patients often experience psychological and physiological pressure due to its invasive nature.The management of patient discomfort and tension is crucial to ensure effective treatment.Psychological and pain management are essential components of interventional therapy,as they significantly impact patient recovery and prognosis.This article discussed the importance of interventional psychological and pain care for patients,starting with the development and spread of interventional therapy.The significance of providing high-quality nursing services to patients and improving their quality of life was also discussed. 展开更多
关键词 Interventional treatment Psychological nursing Pain care Key points Significance analysis
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改进邻域扩展A^(*)算法的移动机器人路径规划
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作者 董雅文 杨静雯 +1 位作者 张宝锋 赵小惠 《机械设计与制造》 北大核心 2025年第1期291-295,共5页
为解决A^(*)算法在规划路径时存在转折角度过大、路径不平滑的问题,提出改进邻域扩展A^(*)算法。首先,对A^(*)算法搜索范围扩展至24邻域,然后对邻域进行二次数量优化处理得到最终邻域搜索节点。其次,设计具有双层位置导向信息的评价函数... 为解决A^(*)算法在规划路径时存在转折角度过大、路径不平滑的问题,提出改进邻域扩展A^(*)算法。首先,对A^(*)算法搜索范围扩展至24邻域,然后对邻域进行二次数量优化处理得到最终邻域搜索节点。其次,设计具有双层位置导向信息的评价函数,最后对所得路径进行二次平滑处理以剔除冗余节点并削弱路径尖峰的剧烈程度。仿真结果表明,改进邻域扩展A^(*)算法在路径长度、搜索节点数量、规划时间上均优于传统A^(*)算法,且路径无尖峰转角,整体趋势平缓。 展开更多
关键词 点对点路径规划 A^(*)算法 邻域扩展
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《中国矿产地质志》研编与新一轮找矿突破行动建议--“庆祝陈毓川院士九十华诞暨从事地质工作70周年”专辑特邀主编寄语
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作者 王登红 《地球学报》 北大核心 2025年第1期2-7,共6页
矿产资源是经济社会发展的重要物质基础,矿产资源勘查开发事关国计民生和国家安全。为保障国家矿产资源安全,当前全国上下正在全面组织实施新一轮找矿突破战略行动,以推动加强国内重要的战略性矿产资源的勘探开发和增储上产,从源头上完... 矿产资源是经济社会发展的重要物质基础,矿产资源勘查开发事关国计民生和国家安全。为保障国家矿产资源安全,当前全国上下正在全面组织实施新一轮找矿突破战略行动,以推动加强国内重要的战略性矿产资源的勘探开发和增储上产,从源头上完善战略性矿产资源探采供储销统筹和衔接体系。为了进一步摸清我国资源家底,全面反映矿产勘查成果和成矿规律,以陈毓川院士为首的科研团队于2012年起牵头组织实施了新中国第一部《中国矿产地质志》研编工作,截至目前,研编工作取得重大进展,完成了200多部志书评审验收,其中,正式出版发行了88部。在《地球学报》编辑部的大力支持下,本专辑共汇集了18篇论文,内容主要涉及到部分全国性矿种组志书和省级矿产地质志研编成果,涵盖铀、锰、铜、铅锌、高纯石英原料矿、金、银、锂、化工等重要矿产篇以及新疆、青海、云南、贵州、广西、内蒙古、河北、吉林等省级篇。通过对已有矿产资源禀赋特征和成矿规律进行了总结,开展了成矿预测,提出了对新一轮找矿突破战略行动的找矿部署建议。 展开更多
关键词 中国矿产地质志 重要矿种 重要省份 找矿建议
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社交网络节点重要性识别研究进展
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作者 郭强 欧阳 +1 位作者 江明珠 刘建国 《电子科技大学学报》 北大核心 2025年第1期125-151,共27页
准确识别社交网络中的节点重要性对于促进或抑制信息传播、遏制疾病传播具有重要意义,同时在精准营销和社会治理等领域也具有重要理论意义和应用价值。该文从4个角度对节点影响力识别算法进行总结和梳理,具体包括:基于微观局部结构、中... 准确识别社交网络中的节点重要性对于促进或抑制信息传播、遏制疾病传播具有重要意义,同时在精准营销和社会治理等领域也具有重要理论意义和应用价值。该文从4个角度对节点影响力识别算法进行总结和梳理,具体包括:基于微观局部结构、中观的社团结构、宏观全局结构及基于机器学习的算法。详细介绍了其中的代表性算法,并从不同层面分析了不同算法的优缺点。此外还总结了常用的传播动力学模型和评价指标。最后提炼了仍需解决的问题和未来可能的研究方向。 展开更多
关键词 社交网络 节点重要性 社团结构 机器学习
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华北落叶松人工林林下物种多样性特征研究
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作者 康义 辛学兵 +5 位作者 裴顺祥 郭慧 法蕾 吴莎 马淑敏 吴迪 《西北林学院学报》 北大核心 2025年第1期23-31,82,共10页
对河北省塞罕坝第三乡林场不同营林区的华北落叶松人工林林下物种多样性进行调查,对比分析不同营林区内林下植被组成及灌木层和草本层的物种重要值、结构特征和物种多样性指数(物种丰富度指数、Simpson优势度指数、Shannon-Wiener多样... 对河北省塞罕坝第三乡林场不同营林区的华北落叶松人工林林下物种多样性进行调查,对比分析不同营林区内林下植被组成及灌木层和草本层的物种重要值、结构特征和物种多样性指数(物种丰富度指数、Simpson优势度指数、Shannon-Wiener多样性指数和Pielou均匀度指数),探究林下植被物种重要值及多样性指数在3个营林区内的变化差异。结果表明,3个营林区内华北落叶松人工林林下植物共116种,隶属44科86属。林下植物的科、属、种总数在3个营林区中表现一致,即母子沟最高,莫里莫次之,北岔最低。灌木层优势科均以蔷薇科居多,草本层优势科则各有不同,显示出明显的地区差异性。莫里莫营林区灌草层的指数值高于其他2个营林区,母子沟居中,北岔最低。莫里莫营林区高灌草层多样性测度指数可能反映该地区生态系统的较高健康度和韧性,而母子沟的中等多样性测度指数可能表明其生态系统正处于过渡状态,北岔营林区的低多样性测度指数暗示生态系统可能面临潜在风险。研究结果对第三乡林场不同营林区内华北落叶松人工林生态系统的健康管理提供了数据支撑。 展开更多
关键词 华北落叶松人工林 物种多样性 物种重要值 林下植物 塞罕坝
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2021~2023年中国蜂蜡进出口贸易情况
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作者 杨林富 姜武韬 +6 位作者 胡百顺 陆丝丝 邓尚靠 田亚凯 周丹银 董坤 龚雪阳 《蜜蜂杂志》 2025年第1期1-4,共4页
文章总结并分析了2021~2023年我国蜂蜡进出口贸易情况,包括我国蜂蜡进出口数量、金额、单价的动态变化,以及出口国别、省份情况,同时探讨了我国蜂蜡贸易存在的主要问题,可为提高我国蜂蜡进出口贸易创汇提供参考建议。
关键词 蜂蜡 进口 出口 贸易
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基于改进DGCNN的树木点云分割方法
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作者 刘超 卜鑫荣 +3 位作者 刘慧 杨官学 沈跃 徐婕 《南京农业大学学报》 CAS 北大核心 2025年第1期240-248,共9页
[目的]通过目标分割为果园喷雾机提供树木的表征信息,使喷雾机能够实现精准喷雾。在分割过程中,对苗圃中的树冠、树干等不同部位进行分割,可以帮助喷雾机对喷雾部分对靶,在果园或苗圃景观中实现自动导航以及精准喷药等操作。与图片相比... [目的]通过目标分割为果园喷雾机提供树木的表征信息,使喷雾机能够实现精准喷雾。在分割过程中,对苗圃中的树冠、树干等不同部位进行分割,可以帮助喷雾机对喷雾部分对靶,在果园或苗圃景观中实现自动导航以及精准喷药等操作。与图片相比,点云能够更好地表征树木的三维结构并且受照明条件影响小,因此针对点云树木设计分割算法更适合应用在果园、苗圃等室外环境作业的农业机械。[方法]本文基于DGCNN提出了一种分割精度准确、参数量小的树木点云分割网络——TSNet,它可以很容易被部署在果园喷雾机上。该网络主要具有以下特点:1)该网络是基于DGCNN改进的,可以更好实现点云分割任务;2)网络引入了连续递归门控卷积模块(g^(n)Conv),可以提高树木分割的准确率;3)为避免全局信息损失并增加信息传递效率,我们设计了权重通道用于特征传递。[结果]TSNet分割树木的mIoU达到90.08%,模型大小为0.72 M,优于PointNet、PointNet++、DGCNN、CurveNet、PointMLP和D-PointNet++等常用的点云分割算法。[结论]TSNet能够为苗圃树木检测识别和农业机器人作业提供更准确的感知信息。 展开更多
关键词 点云 树木分割 深度学习 精准喷雾 果园喷雾机
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国家药品抽检检验机构实验室管理风险点分析及对策
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作者 朱嘉亮 郗昊 +5 位作者 冯磊 徐苗 顾颂青 李睿 孙婷 陈蕾 《医药导报》 CAS 北大核心 2025年第1期68-72,共5页
目的通过梳理近年来国家药品抽检检验流程中潜在风险因素,针对质量管理体系运行情况,对检验机构如何在新的药品监管模式下做好抽检工作提出建议。方法以考察数据完整性、真实性为重点,重点围绕试剂管理、标准物质管理、仪器设施管理、... 目的通过梳理近年来国家药品抽检检验流程中潜在风险因素,针对质量管理体系运行情况,对检验机构如何在新的药品监管模式下做好抽检工作提出建议。方法以考察数据完整性、真实性为重点,重点围绕试剂管理、标准物质管理、仪器设施管理、电子数据管理等风险点进行分析,对质量管理体系运行的有效性等进行全面核查。结果国家药品抽检检验机构应强化全面质量管理,根据本实验室运行情况,结合各自风险特点,在试剂管理、标准物质管理、仪器设施管理、电子数据管理等方面的风险进行系统梳理并建立风险提示功能,制定风险警示清单,实施相应的风险控制策略。结论检验机构应继续加强对运行过程中影响因素的有效控制,重视各项检测工作的关键控制点,持续规范和完善检验过程的质量体系,确保各项质量活动处于受控状态。 展开更多
关键词 国家药品抽检 实验室管理 风险点分析
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