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A Boon for Trade in Services
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作者 ZHANG SHASHA 《ChinAfrica》 2026年第3期22-24,共3页
Saud Khan,a Pakistani physician,collected his work and residence permits at the Yangpu Government Service Centre in Danzhou City,Hainan Province,on 18 December 2025.Khan had arrived in Hainan three months earlier to p... Saud Khan,a Pakistani physician,collected his work and residence permits at the Yangpu Government Service Centre in Danzhou City,Hainan Province,on 18 December 2025.Khan had arrived in Hainan three months earlier to participate in a medical training programme at Hainan Western Central Hospital.By the time the programme concluded,he had made up his mind to stay and broaden his professional experience and long-term career prospects in Hainan. 展开更多
关键词 TRADE residence permit Hainan province work residence permits work permit Yangpu government service centre medical training programme serviceS
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Ecosystem service models are indeed being validated:A response to Pereira et al.(2025)
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作者 James M.Bullock Danny A.P.Hooftman +1 位作者 John W.Redhead Simon Willcock 《Geography and Sustainability》 2026年第1期247-248,共2页
In their recent paper Pereira et al.(2025)claim that validation is overlooked in mapping and modelling of ecosystem services(ES).They state that“many studies lack critical evaluation of the results and no validation ... In their recent paper Pereira et al.(2025)claim that validation is overlooked in mapping and modelling of ecosystem services(ES).They state that“many studies lack critical evaluation of the results and no validation is provided”and that“the validation step is largely overlooked”.This assertion may have been true several years ago,for example,when Ochoa and Urbina-Cardona(2017)made a similar observation.However,there has been much work on ES model validation over the last decade. 展开更多
关键词 evaluation MAPPING modeling es model ecosystem services VALIDATION
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Research on the Optimal Allocation of Community Elderly Care Service Resources Based on Big Data Technology
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作者 Shuying Li 《Journal of Clinical and Nursing Research》 2026年第1期241-246,共6页
With the accelerating aging process of China’s population,the demand for community elderly care services has shown diversified and personalized characteristics.However,problems such as insufficient total care service... With the accelerating aging process of China’s population,the demand for community elderly care services has shown diversified and personalized characteristics.However,problems such as insufficient total care service resources,uneven distribution,and prominent supply-demand contradictions have seriously affected service quality.Big data technology,with core advantages including data collection,analysis and mining,and accurate prediction,provides a new solution for the allocation of community elderly care service resources.This paper systematically studies the application value of big data technology in the allocation of community elderly care service resources from three aspects:resource allocation efficiency,service accuracy,and management intelligence.Combined with practical needs,it proposes optimal allocation strategies such as building a big data analysis platform and accurately grasping the elderly’s care needs,striving to provide operable path references for the construction of community elderly care service systems,promoting the early realization of the elderly care service goal of“adequate support and proper care for the elderly”,and boosting the high-quality development of China’s elderly care service industry. 展开更多
关键词 Big data technology COMMUNITY Elderly care service resources
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Event Detection on Monitoring Internet of Things Services by Fusing Multiple Observations
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作者 Mao Yanfang Zhang Yang +2 位作者 Cheng Bo Zhao Shuai Chen Junliang 《China Communications》 2026年第1期234-254,共21页
Ensuring an information fabric safe is critical and mandatory.For its related Internet of Things(IoT)service system running on the open Internet,existing host-based monitoring methods may fail due to only inspecting s... Ensuring an information fabric safe is critical and mandatory.For its related Internet of Things(IoT)service system running on the open Internet,existing host-based monitoring methods may fail due to only inspecting software,and the physical system may not be able to be protected.In this paper,a nonintrusive virtual machine(VM)-based runtime protection framework is provided to protect the physical system with the isolated IoT services as a controlling means.Compared with existing solutions,the framework gets inconsistent and untrusted observation knowledge from multiple observation sources,and enforces property policies concurrently and incrementally in a competing-game way to avoid compositional problems.In addition,the monitoring is implemented without any modification to the protected system.Experiments are conducted to validate the proposed techniques. 展开更多
关键词 anomaly knowledge checking IoT service runtime monitoring
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Multi-Criteria Discovery of Communities in Social Networks Based on Services
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作者 Karim Boudjebbour Abdelkader Belkhir Hamza Kheddar 《Computers, Materials & Continua》 2026年第3期984-1005,共22页
Identifying the community structure of complex networks is crucial to extracting insights and understanding network properties.Although several community detection methods have been proposed,many are unsuitable for so... Identifying the community structure of complex networks is crucial to extracting insights and understanding network properties.Although several community detection methods have been proposed,many are unsuitable for social networks due to significant limitations.Specifically,most approaches depend mainly on user-user structural links while overlooking service-centric,semantic,and multi-attribute drivers of community formation,and they also lack flexible filtering mechanisms for large-scale,service-oriented settings.Our proposed approach,called community discovery-based service(CDBS),leverages user profiles and their interactions with consulted web services.The method introduces a novel similarity measure,global similarity interaction profile(GSIP),which goes beyond typical similarity measures by unifying user and service profiles for all attributes types into a coherent representation,thereby clarifying its novelty and contribution.It applies multiple filtering criteria related to user attributes,accessed services,and interaction patterns.Experimental comparisons against Louvain,Hierarchical Agglomerative Clustering,Label Propagation and Infomap show that CDBS reveals the higher performance as it achieves 0.74 modularity,0.13 conductance,0.77 coverage,and significantly fast response time of 9.8 s,even with 10,000 users and 400 services.Moreover,community discoverybased service consistently detects a larger number of communities with distinct topics of interest,underscoring its capacity to generate detailed and efficient structures in complex networks.These results confirm both the efficiency and effectiveness of the proposed method.Beyond controlled evaluation,communities discovery based service is applicable to targeted recommendations,group-oriented marketing,access control,and service personalization,where communities are shaped not only by user links but also by service engagement. 展开更多
关键词 Social network communities discovery complex network CLUSTERING web services similarity measure
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Evidence Summary for Discharge Preparation Services in Patients After Total Knee Arthroplasty
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作者 Jiapei Li Jiuqun Li Jinli Wang 《Journal of Clinical and Nursing Research》 2026年第1期96-107,共12页
Objective:To systematically summarize and evaluate the evidence on discharge preparation services for patients undergoing total knee arthroplasty,providing an evidence-based foundation for developing scientific and st... Objective:To systematically summarize and evaluate the evidence on discharge preparation services for patients undergoing total knee arthroplasty,providing an evidence-based foundation for developing scientific and standardized discharge preparation intervention programs in clinical practice.Methods:Following the“5S”evidence model,literature such as guidelines,expert consensuses,evidence summaries and randomized controlled trials related to discharge preparation services for total knee arthroplasty patients were retrieved from relevant websites and databases,both domestic and international,from database inception to August 31,2025.Two researchers independently screened the literature,conducted quality appraisals,and extracted and synthesized the evidence.Results:A total of 15 articles were included,comprising 3 guidelines,4 expert consensuses,3 evidence summaries,3 systematic reviews and 2 randomized controlled trials.Ultimately,23 pieces of evidence were summarized across five aspects.Conclusion:This study synthesizes the evidence on discharge preparation services for patients undergoing total knee arthroplasty.It is recommended that healthcare professionals apply this evidence in clinical practice,considering specific circumstances and patient needs. 展开更多
关键词 Total knee arthroplasty Discharge preparation service Evidence summary Evidence-based nursing REHABILITATION
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Research on Operation Strategies of Trade Publishing Knowledge Service Platform Based on the SICAS Model:A Case Study of CITIC Academy
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作者 WANG Jun ZHOU Xiaoyi 《Cultural and Religious Studies》 2026年第1期13-21,共9页
Amidst evolving user behavior driven by the development of the internet,enhancing the operational quality of trade publishing knowledge service platforms has become a significant challenge for publishing institutions.... Amidst evolving user behavior driven by the development of the internet,enhancing the operational quality of trade publishing knowledge service platforms has become a significant challenge for publishing institutions.To address this issue,this paper employs a combined approach of theoretical analysis and case study,introducing the SICAS(Sense-Interest-Connection-Action-Share)user consumption behavior analysis model and selecting“CITIC Academy”as the case study subject.It systematically examines and summarizes the platform’s operational practices and specific strategies,aiming to offer strategic insights and practical references for the operational improvement and sustainable,high-quality development of trade publishing knowledge service platforms. 展开更多
关键词 trade publishing knowledge service platform SICAS model operation strategy CITIC Academy
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Trade-offs and synergies among ecosystem services and their responses to land use change:A Case study from the subtropical hilly region of Guangdong,Jiangxi and Fujian provinces in China
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作者 WU Jieling ZHA Ruibo +3 位作者 JIANG Xingxue ZHA Xuan HUANG Bowen ZHANG Liu 《Journal of Mountain Science》 2026年第1期343-357,共15页
The Guangdong,Jiangxi and Fujian(GJF)provinces,located in the subtropical region of southeastern China,is one of the national key regions for soil erosion control and ecological restoration.This region is characterize... The Guangdong,Jiangxi and Fujian(GJF)provinces,located in the subtropical region of southeastern China,is one of the national key regions for soil erosion control and ecological restoration.This region is characterized by extensive red soil development and high rainfall erosivity,making it a representative landscape for exploring the interactions between land use change(LUC)and ecosystem services(ES).Despite the recognized importance of ES in hilly regions,comprehensive assessing the impacts of LUC on ES remain limited.This study investigates five key ES:water yield,soil conservation,carbon conservation,food supply,and habitat quality in GJF region from 2000 to 2020.By applying the InVEST model and the Geodetector method,we assessed the trade-offs,synergies,and transitions among ES,identified the natural and social drivers of ES dynamics,and quantified the contribution of LUC to ES changes using the ecosystem service contribution index.The results showed that cropland and woodland were the dominant land use types.Ecological restoration efforts positively influenced ES,with synergies intensifying and trade-offs diminishing over time.Land use conversions,particularly among woodland,grassland,and cropland,exerted significant impacts on ES.In particular,the conversion of woodland to other land uses had markedly negative effects on soil conservation,carbon conservation,and habitat quality.Forest cover was identified as a major driver of ES dynamics.These findings highlight the importance of maintaining and expanding forest and grassland cover,strengthening red soil conservation,and optimizing land use structure to achieve coordinated ecological protection and socioeconomic development in the subtropical hilly regions of southern China. 展开更多
关键词 Land use change Ecosystem services Contribution degree Trade-offs and Synergies Subtropical hilly region
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Research on grain supply and demand matching in the Beijing-Tianjin-Hebei region based on ecosystem service flows
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作者 Jiaxin Miao Peipei Pan +7 位作者 Bingyu Liu XiaowenYuan Zijun Pan Linsi Li Xinyun Wang Yuan Wang Yongqiang Cao Tianyuan Zhang 《Journal of Integrative Agriculture》 2026年第2期460-480,共21页
A comprehensive assessment of grain supply,demand,and ecosystem service flows is essential for identifying grain movement pathways,ensuring regional grain security,and guiding sustainable management strategies.However... A comprehensive assessment of grain supply,demand,and ecosystem service flows is essential for identifying grain movement pathways,ensuring regional grain security,and guiding sustainable management strategies.However,current studies primarily focus on short-term grain provision services while neglecting the spatiotemporal variations in grain flows across different scales.This gap limits the identification of dynamic matching relationships and the formulation of optimization strategies for balancing grain flows.This study examined the spatiotemporal evolution of grain supply and demand in the Beijing-Tianjin-Hebei(BTH)region from 1980 to 2020.Using the Enhanced TwoStep Floating Catchment Area method,the grain provision ecosystem service flows were quantified,the changes in supply–demand matching under different grain flow scenarios were analyzed and the optimal distance threshold for grain flows was investigated.The results revealed that grain production follows a spatial distribution pattern characterized by high levels in the southeast and low levels in the northwest.A significant mismatch exists between supply and demand,and it shows a scale effect.Deficit areas are mainly concentrated in the northwest,while surplus areas are mainly located in the central and southern regions.As the spatial scale increases,the ecosystem service supply–demand ratio(SDR)classification becomes more clustered,while it exhibits greater spatial SDR heterogeneity at smaller scales.This study examined two distinct scenarios of grain provision ecosystem service flow dynamics based on 100 and 200 km distance thresholds.The flow increased significantly,from 2.17 to 11.81million tons in the first scenario and from 2.41 to 12.37 million tons in the second scenario over nearly 40 years,forming a spatial movement pattern from the central and southern regions to the surrounding areas.Large flows were mainly concentrated in the interior of urban centers,with significant outflows between cities such as Baoding,Shijiazhuang,Xingtai,and Hengshui.At the county scale,supply–demand matching patterns remained consistent between the grain flows in the two scenarios.Notably,incorporating grain flow dynamics significantly reduced the number of grain-deficit areas compared to scenarios without grain flow.In 2020,grain-deficit counties decreased by28.79 and 37.88%,and cities by 12.50 and 25.0%under the two scenarios,respectively.Furthermore,the distance threshold for achieving optimal supply and demand matching at the county scale was longer than at the city scale in both grain flow scenarios.This study provides valuable insights into the dynamic relationships and heterogeneous patterns of grain matching,and expands the research perspective on grain and ecosystem service flows across various spatiotemporal scales. 展开更多
关键词 Beijing-Tianjin-Hebei region grain provision ecosystem service grain flow supply and demand match distance threshold
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Home-Based Care Service
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作者 XU JUNXING 《China Today》 2026年第3期70-72,共3页
Hebei Province has incorporated targeted assistance services for people with disabilities into livelihood projects,upgrading the quality and efficiency of support services for disadvantaged groups.THE living and nursi... Hebei Province has incorporated targeted assistance services for people with disabilities into livelihood projects,upgrading the quality and efficiency of support services for disadvantaged groups.THE living and nursing allowances provided by the Chinese government for people with disabilities who are unable to work are not only important components of China’s social security system which provide for the needs of its disabled,but also show China’s ability to guarantee the basic living standard and social fairness and justice for this group of people. 展开更多
关键词 livelihood projects home based care targeted assistance livelihood projectsupgrading people disabilities living nursing allowances targeted assistance services social security system
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Cognitive NFIDC-FRBFNN Control Architecture for Robust Path Tracking of Mobile Service Robots in Hospital Settings
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作者 Huda Talib Najm Ahmed Sabah Al-Araji Nur Syazreen Ahmad 《Computer Modeling in Engineering & Sciences》 2026年第1期989-1022,共34页
Mobile service robots(MSRs)in hospital environments require precise and robust trajectory tracking to ensure reliable operation under dynamic conditions,including model uncertainties and external disturbances.This stu... Mobile service robots(MSRs)in hospital environments require precise and robust trajectory tracking to ensure reliable operation under dynamic conditions,including model uncertainties and external disturbances.This study presents a cognitive control strategy that integrates a Numerical Feedforward Inverse Dynamic Controller(NFIDC)with a Feedback Radial Basis Function Neural Network(FRBFNN).The robot’s mechanical structure was designed in SolidWorks 2022 SP2.0 and validated under operational loads using finite element analysis in ANSYS 2022 R1.The NFIDC-FRBFNN framework merges proactive inverse dynamic compensation with adaptive neural learning to achieve smooth torque responses and accurate motion control.A two-stage simulation evaluation was conducted.In the first stage,the controller was tested in a simulated hospital environment under both ideal and non-ideal conditions.In the second,it was benchmarked against four established controllers-Neural Network Model Reference Adaptive(NNMRA),Z-number Fuzzy Logic(Z-FL),Adaptive Dynamic Controller(ADC),and Fuzzy Logic-PID(FL-PID)—using circular and lemniscate trajectories.Across ten runs,the proposed controller achieved the lowest tracking errors under all conditions.Under ideal conditions,it achieved average improvements of 55.24%,75.75%,and 55.20%in integral absolute error(IAE),integral squared error(ISE),and mean absolute error(MAE),respectively,with coefficient of variation(CV)reductions above 55%.Under non-ideal conditions,average improvements exceeded 64%in IAE,77%in ISE,and 66%in MAE,while maintaining CV reductions above 57%.These results confirm that the NFIDC-FRBFNN controller offers superior accuracy,robustness,and consistency for real-time path tracking in healthcare robotics. 展开更多
关键词 Mobile service robot path planning radial basis function neural network trajectory tracking numerical feed forward inverse dynamic controller
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基于SDP的LTE-R网络零信任架构设计
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作者 李明洋 王炫哲 陶雨婷 《铁路计算机应用》 2026年第1期71-76,共6页
随着LTE-R(Long Term Evolution for Railways)网络的发展,传统安全架构难以应对日益复杂的安全威胁,特别是针对网络边界逐渐模糊、“非法用户”越权访问等问题。文章结合“永不信任,始终验证”的零信任理念,提出一种基于软件定义边界(S... 随着LTE-R(Long Term Evolution for Railways)网络的发展,传统安全架构难以应对日益复杂的安全威胁,特别是针对网络边界逐渐模糊、“非法用户”越权访问等问题。文章结合“永不信任,始终验证”的零信任理念,提出一种基于软件定义边界(SDP,Software Defined Perimeter)的LTE-R网络零信任架构。该架构融合单包授权(SPA,Single Packet Authorization)、持续认证机制和行为审计策略,实现服务端口隐身、最小权限控制及动态权限管理,有效防御横向渗透、中间人攻击和端口扫描,为保障LTE-R核心调度系统安全和铁路通信网络的零信任转型提供了可行路径。 展开更多
关键词 零信任 软件定义边界 LTE-R网络安全 单包授权 动态授权 铁路网络安全
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用JWSDP构建校园Web Services信息共享平台 被引量:1
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作者 杜娟 《西南科技大学学报》 CAS 2006年第1期18-21,共4页
介绍了如何采用JWSDP(Java Web Services Developer Pack)构建一个基于私有UDDI注册表服务器的能动态地描述、发布、发现和调用服务的Web Services信息共享平台,从而可以实现在高校内部现有的异构平台上构筑一个通用的、与平台、语言无... 介绍了如何采用JWSDP(Java Web Services Developer Pack)构建一个基于私有UDDI注册表服务器的能动态地描述、发布、发现和调用服务的Web Services信息共享平台,从而可以实现在高校内部现有的异构平台上构筑一个通用的、与平台、语言无关的技术层,进而实现各学院、部门之间各种应用的彼此连接和集成。 展开更多
关键词 分布式系统 WEB serviceS JWsdp(Java WEB serviceS DEVELOPER Pack) 信息平台
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基于SDP与EfficientNet的特征级融合滚动轴承故障诊断
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作者 傅媛 陈磊 +1 位作者 杨泮 张婷婷 《科学技术创新》 2025年第22期90-93,共4页
针对传统故障诊断方法难以直观看出滚动轴承的健康状态,提出了基于点对称SDP与EfficientNet故障诊断模型的特征级融合方法。首先采用SDP技术将采集得到的信号进行特征级融合,可以初步直观看出监测对象的健康状态,其次利用EfficientNet... 针对传统故障诊断方法难以直观看出滚动轴承的健康状态,提出了基于点对称SDP与EfficientNet故障诊断模型的特征级融合方法。首先采用SDP技术将采集得到的信号进行特征级融合,可以初步直观看出监测对象的健康状态,其次利用EfficientNet故障诊断算法与特征级融合后的SDP图像进行结合,可以得到监测对象的故障诊断结果。然后利用美国凯斯西储大学滚动轴承公用数据集进行实验验证,结果显示该方法对于轴承健康状态诊断的准确度达到98.7%,最后,将所提方法与ShuffleNet网络进行对比,可以得到所提方法的准确度更高。 展开更多
关键词 轴承 故障诊断 sdp 特征融合 EfficientNet
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热处理工艺对SDP80C钢组织及性能的影响 被引量:1
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作者 陈晟楠 彭睿智 吴晓春 《金属热处理》 北大核心 2025年第2期241-246,共6页
利用热膨胀相变仪测定了预硬型压铸模具钢SDP80C的奥氏体连续冷却转变曲线,研究了不同时效工艺下的组织与力学性能。结果表明,SDP80C钢的马氏体开始转变温度(Ms)为320℃,奥氏体开始转变温度(Ac_(1))为695℃,奥氏体转变终了温度(Ac_(3))... 利用热膨胀相变仪测定了预硬型压铸模具钢SDP80C的奥氏体连续冷却转变曲线,研究了不同时效工艺下的组织与力学性能。结果表明,SDP80C钢的马氏体开始转变温度(Ms)为320℃,奥氏体开始转变温度(Ac_(1))为695℃,奥氏体转变终了温度(Ac_(3))为841℃。在525~600℃时效温度范围内,时效温度的升高促进NiAl相和富Cu相的形成和生长,且马氏体组织发生回复,综合作用下SDP80C钢硬度逐渐降低,冲击性能得到提高。在525℃时效2 h后,由于纳米级NiAl相和富Cu相的析出强化,SDP80C钢达到最大硬度44.9 HRC,冲击吸收能量约为123 J。 展开更多
关键词 压铸模具钢sdp80C 时效工艺 硬度 冲击性能 NiAl相
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大豆脂肪酶SDP1生物信息学分析和基因编辑
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作者 谷心如 刘新宇 +5 位作者 韩旭达 赵长江 费志宏 魏金鹏 徐晶宇 李佐同 《大豆科学》 北大核心 2025年第2期53-63,共11页
三酰甘油脂肪酶(Suger-dependent1,SDP1)是一种脂解酶,在植物发育过程中发挥重要作用。为发掘大豆SDP1基因的生物学功能,利用生物信息学分析方法对大豆GmSDP1基因的进化关系、保守基序和启动子区域的顺式作用元件等进行分析。利用基因... 三酰甘油脂肪酶(Suger-dependent1,SDP1)是一种脂解酶,在植物发育过程中发挥重要作用。为发掘大豆SDP1基因的生物学功能,利用生物信息学分析方法对大豆GmSDP1基因的进化关系、保守基序和启动子区域的顺式作用元件等进行分析。利用基因编辑技术创制大豆gmsdp1-1^(CR)突变体,对其编辑事件、含油量以及脂肪酸含量进行分析。结果表明:4个大豆GmSDP 1基因与双子叶植物亲缘关系较近,保守结构域和蛋白二级结构高度相似,启动子区域含有抗逆境胁迫以及激素相关的调控元件。对GmSDP1在不同组织部位的表达量分析发现,GmSDP1在子叶、叶片和花等部位表达较高。运用CRISPR-Cas9基因编辑技术创制大豆Willimas 82品种的gmsdp1-1^(CR)突变体,设计1条靶向目的基因GmSDP1-1的特异靶点,构建pGES201-GmSDP1-1敲除载体。毛根转化试验的阳性大豆毛状根编辑效率达到56.52%。大豆稳定转化的T_(1)代基因编辑阳性植株编辑效率为1.5%,选取gmsdp1-1^(CR)突变体做进一步表型分析表明,油酸含量极显著降低,亚麻酸含量极显著升高。研究结果为深入研究GmSDP1基因的功能和调控机制提供了参考依据。 展开更多
关键词 大豆 sdp1基因 CRISPR/Cas9技术 生物信息学分析 组织特异性表达
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回火工艺对SDP1Cu塑料模具钢组织与力学性能的影响
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作者 陈旋 符蓉 +5 位作者 宗林 吴明辉 冒新国 李欣欣 翟庆华 何西娟 《金属热处理》 北大核心 2025年第5期181-189,共9页
利用扫描电镜、透射电镜和洛氏硬度计,研究了回火温度和时间对不同淬火基体组织的SDP1Cu钢组织和力学性能的影响。结果表明,在回火过程中,随着回火温度从350℃升高到600℃,马氏体淬火组织钢的硬度从42.50 HRC(350℃×1 h)下降到32.0... 利用扫描电镜、透射电镜和洛氏硬度计,研究了回火温度和时间对不同淬火基体组织的SDP1Cu钢组织和力学性能的影响。结果表明,在回火过程中,随着回火温度从350℃升高到600℃,马氏体淬火组织钢的硬度从42.50 HRC(350℃×1 h)下降到32.00 HRC(600℃×1 h),回火温度超过550℃,随着回火时间的延长,硬度急剧下降;回火温度从350℃升高到600℃,贝氏体淬火组织钢的硬度先上升后下降,在475℃回火2 h时达到硬度峰值39.50 HRC;回火温度选择500℃,回火2~20 h可以使两种淬火组织的硬度差值降低到±0.5 HRC,获得良好的硬度均匀性。马氏体组织钢以回火软化为主,主要变化为板条回复、碳化物析出;贝氏体组织钢的组织演化以析出强化为主,主要发生M/A岛的分解、M_(23)C_(6)型碳化物的析出和富铜相的析出。 展开更多
关键词 塑料模具钢 sdp1Cu钢 回火 马氏体 贝氏体 硬度均匀性
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Quantifying the impacts of land use/land cover changes on ecosystem service values in the upper Gilgel Abbay watershed,Ethiopia 被引量:1
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作者 Wassie Abuhay ASCHENEFE Temesgen Gashaw TAREKEGN +1 位作者 Betelhem Fetene ADMAS Solomon Mulu TAFERE 《Regional Sustainability》 2025年第1期63-74,共12页
Human well-being and livelihoods depend on natural ecosystem services(ESs).Following the increment of population,ESs have been deteriorated over time.Ultimately,land use/land cover(LULC)changes have a profound impact ... Human well-being and livelihoods depend on natural ecosystem services(ESs).Following the increment of population,ESs have been deteriorated over time.Ultimately,land use/land cover(LULC)changes have a profound impact on the change of ecosystem.The primary goal of this study is to determine the impacts of LULC changes on ecosystem service values(ESVs)in the upper Gilgel Abbay watershed,Ethiopia.Changes in LULC types were studied using three Landsat images representing 1986,2003,and 2021.The Landsat images were classified using a supervised image classification technique in Earth Resources Data Analysis System(ERDAS)Imagine 2014.We classified ESs in this study into four categories(including provisioning,regulating,supporting,and cultural services)based on global ES classification scheme.The adjusted ESV coefficient benefit approach was employed to measure the impacts of LULC changes on ESVs.Five LULC types were identified in this study,including cultivated land,forest,shrubland,grassland,and water body.The result revealed that the area of cultivated land accounted for 64.50%,71.50%,and 61.50%of the total area in 1986,2003,and 2021,respectively.The percentage of the total area covered by forest was 9.50%,5.90%,and 14.80%in 1986,2003,and 2021,respectively.Result revealed that the total ESV decreased from 7.42×10^(7) to 6.44×10^(7) USD between 1986 and 2003.This is due to the expansion of cultivated land at the expense of forest and shrubland.However,the total ESV increased from 6.44×10^(7) to 7.76×10^(7) USD during 2003-2021,because of the increment of forest and shrubland.The expansion of cultivated land and the reductions of forest and shrubland reduced most individual ESs during 1986-2003.Nevertheless,the increase in forest and shrubland at the expense of cultivated land enhanced many ESs during 2003-2021.Therefore,the findings suggest that appropriate land use practices should be scaled-up to sustainably maintain ESs. 展开更多
关键词 Ecosystem service values(ESVs) Land use/land cover(LULC) Ecosystem services(ESs) Provisioning service Gilgel Abbay watershed
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How does urbanization evolve heterogeneously in urbanized,urbanizing,and rural areas of China?Insights from ecosystem service value 被引量:2
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作者 Yikun Zhang Yongsheng Wang 《Geography and Sustainability》 2025年第3期117-128,共12页
The rapid population and land urbanization not only promoted economic development but also affected the ecosystem service value(ESV).In the context of new-type urbanization and green development,it’s essential to inv... The rapid population and land urbanization not only promoted economic development but also affected the ecosystem service value(ESV).In the context of new-type urbanization and green development,it’s essential to investigate the impacts of urbanization on ESV in China.However,a comprehensive and dynamic framework to reveal the relationship between ESV and urbanization processes is lacking.This study adopted multi-source datasets to portray China’s urbanization process by integrating population,land,and economic urbanization,eval-uated the ESV changes of 10 categories by gross ecosystem product(GEP)methods,and explored ESV changes within different urbanization scales and speeds.The results showed rapid urbanization in the population,land,and economic dimensions in China,with a faster process of economic urbanization.The ESV also exhibited an increasing trend,with higher levels in the southeastern coastal regions and lower levels in the northwestern regions.Urbanization had positive impacts on ESV across various research units,but the ESV exhibited heteroge-neous changes across different urbanization scales,speeds,and their interactive effects.The response of ESV to dynamic urbanization processes was influenced by socio-economic,ecological,and policy factors;it is essential to combine targeted measures with general ecological product value realization methods in each unit to maximize social-economic-ecological benefits. 展开更多
关键词 URBANIZATION Urban-rural areas Ecosystem service value Social-economic-ecological benefits China
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基于改进SDP和FasterNet-GCAM的滚动轴承故障诊断
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作者 陈家芳 唐湛恒 周健 《现代制造工程》 北大核心 2025年第7期129-138,41,共11页
对滚动轴承进行故障诊断关乎设备运行安全及稳定可靠性。使用传统卷积神经网络进行故障诊断,模型运算量过大,且易出现过拟合现象从而导致诊断精度不高,端到端模型存在可信度不高等问题。鉴于此,提出一种基于改进对称极坐标(Symmetrized ... 对滚动轴承进行故障诊断关乎设备运行安全及稳定可靠性。使用传统卷积神经网络进行故障诊断,模型运算量过大,且易出现过拟合现象从而导致诊断精度不高,端到端模型存在可信度不高等问题。鉴于此,提出一种基于改进对称极坐标(Symmetrized Dot Pattern,SDP)法和FasterNet-GCAM网络的滚动轴承故障诊断方法。首先,将一维振动信号经过小波阈值降噪处理,再输入经皮尔逊图像相关系数法优化的SDP法生成SDP图像,并通过在FasterNet网络中加入部分卷积(partial convolution)思想,构建成改进的SDP-FasterNet模型进行进一步的特征提取,并完成滚动轴承不同故障的分类诊断。为了验证模型在图像识别过程中决策的可信度,将梯度加权类激活映射(Gradient-weighted Class Activation Mapping,Grad-CAM)与FasterNet网络相结合,突出SDP图像与决策相关的重要部分。试验结果表明,所提方法相比于其他方法具有更快的收敛速度和更强的鲁棒性,且诊断识别精度达到了99.20%,并提高了诊断过程中的可解释性及可信度,为故障诊断领域提供了具备良好可行性和鲁棒性的轻量化诊断模型。 展开更多
关键词 滚动轴承 故障诊断 FasterNet网络 部分卷积 梯度加权类激活映射 对称极坐标法
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