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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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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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热处理工艺对SDP80C钢组织及性能的影响
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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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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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基于SSA-VMD和SDP的双通道CNN轴承故障识别方法 被引量:4
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作者 蒋丽英 高铭悦 李贺 《机电工程》 北大核心 2025年第2期257-266,共10页
针对滚动轴承故障振动信号具有非线性和非平稳性等特征,以及单通道卷积神经网络(CNN)提取故障特征不显著的问题,提出了一种基于麻雀算法-变分模态分解(SSA-VMD)和对称点模式(SDP)的双通道CNN滚动轴承故障诊断方法。首先,结合样本熵和皮... 针对滚动轴承故障振动信号具有非线性和非平稳性等特征,以及单通道卷积神经网络(CNN)提取故障特征不显著的问题,提出了一种基于麻雀算法-变分模态分解(SSA-VMD)和对称点模式(SDP)的双通道CNN滚动轴承故障诊断方法。首先,结合样本熵和皮尔逊相关系数,构建了新的综合适应度函数,利用麻雀算法(SSA)进行了自适应寻优,确定了最佳的变分模态分解(VMD)参数K和α。将原始振动信号经过VMD分解后,得到了本征模态函数(IMF)分量,通过计算各IMF分量的峭度值进行了筛选,将筛选出的信号进行重构后得到了一维特征信号;然后,根据互相关系数选择了合适的对称点模式(SDP)参数值,将原始振动信号转化为极坐标下的SDP图像,获得了具有良好可分性的二维特征图;最后,将一维和二维特征作为双通道CNN的输入进行了联合训练,将训练好的网络用于故障类型识别,在西储大学和江南大学的轴承数据集上对其有效性进行了验证。研究结果表明:通过网络训练,其故障诊断的准确率分别达到了98.5%和100%。该结果验证了该方法在准确识别故障特征方面具有优越性和普适性。 展开更多
关键词 一维特征信号构建 二维特征转换 卷积神经网络 麻雀算法 变分模态分解 对称点模式
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Meta-synthesis of the experience of nurses with“Internet Nursing Service”in China 被引量:1
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作者 Wenyan Liu Yao Li +3 位作者 Huanhuan Zhu Kexin Li Haiting Deng Xiaoyan Cai 《International Journal of Nursing Sciences》 2025年第3期233-240,I0003,I0004,共10页
Objective Systematically integrate nurses’experience with“Internet Nursing Service”to analysis the nurses’experiences with“Internet Nursing Service”,and to provide a theoretical reference for formulating a more ... Objective Systematically integrate nurses’experience with“Internet Nursing Service”to analysis the nurses’experiences with“Internet Nursing Service”,and to provide a theoretical reference for formulating a more rational“Internet Nursing Service”model.Methods A systematic search in PubMed,Embase,Web of Science,the Cochrane Library,CINAHL,China National Knowledge Infrastructure(CNKI),Wanfang Database,and Chinese Biomedical Literature Database was conducted to collect qualitative research on nurses’experiences with“Internet Nursing Service,”with a retrieval time limit from December 2019 to June 2024.Qualitative meta-synthesis was performed through line-by-line coding of relevant quotes,organization of codes into descriptive themes,and development of analytical themes.Results A total of 19 studies were included,one study was rated as Grade A in quality evaluation,and the remaining studies were rated as Grade B.Collectively synthesized into three integrated results:Harvest and growth,Difficulties and challenges,and Expectations and support.Harvest and growth,include 1)manifestation of self-value,2)enhancing nursing capabilities,3)optimizing nursing resources;Difficulties and challenges,include 1)lack of safety guarantee,2)role conflict;Expectations and support include,1)expectation for professional knowledge and skill training,2)expectations for service platform optimization,3)expectation for reasonable charges,4)expectation for related policy support.Conclusion“Internet Nursing Service”model benefits both nurses and patients,but still full of challenges.It aids in the decentralization of medical resources.Management departments still need to encourage nurses to actively invest in“Internet Nursing Service”while ensuring their safety and interests. 展开更多
关键词 Internet Nursing service META-SYNTHESIS NURSING Nurse work experience Qualitative research
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ZTE Showcased UMTS/HSDPA Equipment and IMS Converged Services at 3GSM World Congress 2006
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《ZTE Communications》 2006年第1期65-65,共1页
关键词 ZTE Showcased UMTS/HsdpA Equipment and IMS Converged services at 3GSM World Congress 2006 HsdpA UMTS IMS World GSM
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基于SDP的高校融合门户部署及安全性研究
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作者 冯小玲 《中国现代教育装备》 2025年第5期26-29,共4页
如何解决高校师生在校外访问校内网络的身份认证、访问控制与便捷操作之间的矛盾是高校智慧校园建设亟待解决的问题。阐述了SDP三维架构的零信任模式,通过对高校VPN进行“动态+细粒度”的访问控制、用户授权策略的零信任网络部署,实现了... 如何解决高校师生在校外访问校内网络的身份认证、访问控制与便捷操作之间的矛盾是高校智慧校园建设亟待解决的问题。阐述了SDP三维架构的零信任模式,通过对高校VPN进行“动态+细粒度”的访问控制、用户授权策略的零信任网络部署,实现了与VPN的融合共存,并对部署过程中的关键技术问题进行了深入分析和研究,提出了相应的解决方案,实现对用户的身份验证和对设备、应用程序、资源共享等的使用授权,实时感知融合门户的安全管理风险,提升高校校园网络的可靠性和安全性。 展开更多
关键词 零信任 sdp 动态授权 访问控制 融合门户
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Quantifying and Mapping the Effects of Ecosystem Services on Agricultural Competitiveness:A Case Study in Shandong Province,China 被引量:1
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作者 ZHONG Jiali SUN Qian +1 位作者 QI Wei YU Xinyang 《Chinese Geographical Science》 2025年第2期326-342,共17页
Quantifying and mapping how ecosystem services impact agricultural competitiveness is crucial for attaining the Sustainable Development Goals of United Nations.However,few study quantified agricultural competitiveness... Quantifying and mapping how ecosystem services impact agricultural competitiveness is crucial for attaining the Sustainable Development Goals of United Nations.However,few study quantified agricultural competitiveness and mapped the effects of ecosystem services on agricultural competitiveness using multiple models.In this study,multi-source data from 2000 to 2020 were utilized to establish the indicator system of agricultural competitiveness;five ecosystem services were quantified using computation models;Geographic Information System(GIS)spatial analysis was used to explore the spatial patterns of agricultural competitiveness and ecosystem services;geographic detector models were applied to investigate the effects and driving mechanisms of ecosystem services on agricultural competitiveness.Shandong Province of China was selected as the case study area.The results demonstrated that:1)there was a significant increase in agricultural competitiveness during the study period,with high levels observed mainly in the east region of the study area.2)The spatial distribution patterns of ecosystem services and agricultural competitiveness primarily exhibited High-High and Low-Low Cluster types.3)Habitat quality emerged as the main driving factor of agricultural competitiveness in 2000 and 2020,while water yield played a substantial role in 2010.4)The coupling of two ecosystem services exerted a greater effect on agricultural competitiveness compared to individual ecosystem service.The innovations of this study are constructing an indicator system to quantify agricultural competitiveness,and exploring the effects of ecosystem services on agricultural competitiveness.This study proposed an indicator system to quantify agricultural competitiveness,which can be applied in other regions,and explored the effects of ecosystem services on agricultural competitiveness.The findings of this study can serve as valuable insights for policymakers to formulate tailored agricultural development policies that take into account the synergistic effects of ecosystem services on agricultural competitiveness. 展开更多
关键词 agricultural competitiveness ecosystem services spatial autocorrelation geographic detector Shandong Province China
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Access to health services and factors affecting musculoskeletal disorders among outdoor pollution workers following Sustainable Development Goals:a weakness in Thailand 被引量:1
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作者 Anamai Thetkathuek Marissa Kongsombatsuk +1 位作者 Teeranun Nakyai Chan Pattama Polyong 《Global Health Journal》 2025年第2期85-93,共9页
Background:People working outdoors in the Map Ta Phut pollution control area of Thailand require comprehen-sive health monitoring.In the past,studies have been done on the health effects of pollutants.However,there ar... Background:People working outdoors in the Map Ta Phut pollution control area of Thailand require comprehen-sive health monitoring.In the past,studies have been done on the health effects of pollutants.However,there are few studies on musculoskeletal disorders(MSDs),and Thailand is struggling to meet the Sustainable Development Goals.Methods:This cross-sectional study examines access to health services and factors affecting MSDs among outdoor pollution workers(OPWs).The sample group includes OPWs,including local fisherman,street vendors,public car drivers,and traffic police.We studied 50 people from each of these groups,for a total of 200 people.Data were analyzed with inferential statistics using Chi-square test,McNemar test,and Univariate logistic regression.Results:The OPWs reported experiencing significantly more total MSDs pain than they did in the past(P<0.05).Factors affecting current MSDs pain,including occupation and working days per week,were significant(P<0.05).The street vendor group and public car driver group had(odds ratio[OR]=2.253,95%confidence interval[CI]:1.101 to 5.019)and(OR=2.681,95%CI:1.191 to 6.032)times higher risks of MSDs pain,respectively.OPWs who work>5 days per week had a(OR=1.464,95%CI:1.093 to 2.704)times higher risk of MSDs pain.52.7%of OPWs with MSDs,pain(n=110)had received an annual health check-up.In the past year,50.9%had minor illnesses and 21.8%had severe illnesses.OPWs receiving free treatment and visiting health service stations for no cost comprised 77.3%and 51.8%,respectively.60.9%used their right to receive treatment with universal health insurance cards.Conclusions:The study indicates that occupational groups with MSDs pain problems should exercise this right,according to the worker protection law.Local health agencies should organize activities or create accessible media to promote preventive medicine services,as many OPWs believe that health services can only be accessed when illness occurs. 展开更多
关键词 Musculoskeletal disorders Outdoor pollution workers Access to health services Sustainable development goals
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基于改进的SDP点对称特征融合图像的电机故障诊断
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作者 罗瑜 樊赫 郎启发 《计算机测量与控制》 2025年第11期149-157,共9页
针对传统时频分析方法在复杂工况下电机故障信号处理中存在的抗噪能力弱、特征区分度低等问题,提出一种基于改进对称点模式特征融合图像的电机故障诊断方法;采用变分模态分解对故障信号进行自适应分解,结合粒子群优化算法动态调整SDP镜... 针对传统时频分析方法在复杂工况下电机故障信号处理中存在的抗噪能力弱、特征区分度低等问题,提出一种基于改进对称点模式特征融合图像的电机故障诊断方法;采用变分模态分解对故障信号进行自适应分解,结合粒子群优化算法动态调整SDP镜像对称平面旋转角θ、时间间隔参数l、角度放大因子ξ等关键参数,生成多模态信号融合的SDP图像;并构建轻量化卷积神经网络模型对电机故障诊断进行了研究;以变频三相异步电机为实验对象,对正常、匝间短路、气隙偏心、转子断条四类工况采集1200组振动信号样本进行验证;结果表明,所提方法在故障诊断中实现了100%的准确率,优于支持向量机的97.85%、随机森林95.24%,在-6 dB强噪声环境下仍保持98.76%的准确率,验证了其鲁棒性。该方法通过参数优化与特征融合提升了噪声环境下的诊断可靠性,为电机实时监测与智能诊断提供了有效解决方案。 展开更多
关键词 电机故障诊断 sdp方法 VMD 参数PSO寻优 特征融合 CNN模型
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Ultra-Dense LEO Satellite-Aircraft Access and Service Management in Civil Aviation 被引量:1
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作者 Wang Yilei Ma Ting +3 位作者 Liu Xiaoyu Gao Zhuxuan Zhou Haibo Shen Xuemin 《China Communications》 2025年第1期277-292,共16页
With the deployment of ultra-dense low earth orbit(LEO)satellite constellations,LEO satellite access network(LEO-SAN)is envisioned to achieve global Internet coverage.Meanwhile,the civil aviation communications have i... With the deployment of ultra-dense low earth orbit(LEO)satellite constellations,LEO satellite access network(LEO-SAN)is envisioned to achieve global Internet coverage.Meanwhile,the civil aviation communications have increased dramatically,especially for providing airborne Internet services.However,due to dynamic service demands and onboard LEO resources over time and space,it poses huge challenges in satellite-aircraft access and service management in ultra-dense LEO satellite networks(UDLSN).In this paper,we propose a deep reinforcement learning-based approach for ultra-dense LEO satellite-aircraft access and service management.Firstly,we develop an airborne Internet architecture based on UDLSN and design a management mechanism including medium earth orbit satellites to guarantee lightweight management.Secondly,considering latency-sensitive and latency-tolerant services,we formulate the problem of satellite-aircraft access and service management for civil aviation to ensure service continuity.Finally,we propose a proximal policy optimization-based access and service management algorithm to solve the formulated problem.Simulation results demonstrate the convergence and effectiveness of the proposed algorithm with satisfying the service continuity when applying to the UDLSN. 展开更多
关键词 civil aviation deep reinforcement learning satellite-aircraft access service management ultra-dense LEO satellite network
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Multi-scenario simulation of land use change and its impact on ecosystem services in the northeastern edge of the Qinghai-Xizang Plateau,China 被引量:1
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作者 ZHANG Xuebin LIU Yanni +3 位作者 YIN Junfeng SHI Peiji FENG Haoyuan SHI Jing 《Journal of Arid Land》 2025年第2期145-166,共22页
The Qinghai-Xizang Plateau(QXP)serves as a crucial ecological barrier in China and Asia,exerting profound influences on global climate and biodiversity conservation.Gannan Tibetan Autonomous Prefecture(hereinafter ref... The Qinghai-Xizang Plateau(QXP)serves as a crucial ecological barrier in China and Asia,exerting profound influences on global climate and biodiversity conservation.Gannan Tibetan Autonomous Prefecture(hereinafter referred as Gannan Prefecture),located on the northeastern edge of the QXP,represents a fragile alpine ecosystem in which land use change significantly impacts ecosystem services(ESs).This study established a comprehensive framework,utilizing the Patch-generating Land-Use Simulation(PLUS)model coupled with the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model to predict land use patterns under the natural development scenario,cultivated land protection scenario,and ecological protection scenario for Gannan Prefecture by 2030 and evaluated four critical ESs:habitat quality(HQ),water yield(WY),soil retention(SR),and carbon storage(CS).The primary aim is to elucidate the impacts of dynamic land use change on ESs.The results revealed that,from 2000 to 2020,HQ exhibited minimal variation,whereas CS experienced a slight decline.Conversely,WY and SR showed significant improvements.Under the natural development scenario,construction land was projected to increase by 4247.74 hm^(2),primarily at the expense of forest land.The cultivated land protection scenario anticipated an increase in farmland by 2634.36 hm^(2),which was crucial for maintaining food security.The ecological protection scenario predicted a notable expansion of forest land,accompanied by a restrained development rate of construction land.The ecological protection scenario also showed an increase in the ecosystem service index(ESI),encompassing 26.07%of the region.Forest land and grassland emerged as the primary contributors to ESs,while construction land substantially impacted WY.Water bodies exhibited minimal contribution to ESs.This study enhanced the understanding of land use change impacts on ESs in fragile and high-altitude ecosystems,offering essential theoretical frameworks and practical direction for forthcoming ecological policy and regional planning endeavors. 展开更多
关键词 PLUS-InVEST model ecosystem service habitat quality water yield soil retention carbon storage Qinghai-Xizang Plateau
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基于零信任SDP的多模态异构无线融合网络安全防护
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作者 韩春福 高宇翔 +1 位作者 王玉娇 杜芳存 《微型电脑应用》 2025年第8期299-303,共5页
为了有效防护多模态异构无线融合网络攻击,提出基于零信任软件定义边界(SDP)的多模态异构无线融合网络安全防护方法。采用信息熵和改进k-means聚类方法对多模态异构无线融合网络信息展开聚类分析,获取流量数据的时序以及周期性等特征,... 为了有效防护多模态异构无线融合网络攻击,提出基于零信任软件定义边界(SDP)的多模态异构无线融合网络安全防护方法。采用信息熵和改进k-means聚类方法对多模态异构无线融合网络信息展开聚类分析,获取流量数据的时序以及周期性等特征,通过以上特征展开用户访问行为持续信任评估。建立零信任SDP安全模型,通过模型对用户基础身份展开认证和动态访问控制,完成多模态异构无线融合网络安全防护。实验结果表明,所提方法可以更好地确保异构无线融合网络的安全性,对网络安全运行具有参考意义。 展开更多
关键词 零信任sdp 多模态异构无线融合网络 安全防护 信息熵 K-MEANS聚类
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Relationship between the use of smart medical services and mental health status
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作者 Elif Sarac 《World Journal of Psychiatry》 SCIE 2025年第1期21-25,共5页
In this editorial,I comment on the article by Zhang et al.To emphasize the importance of the topic,I discuss the relationship between the use of smart medical devices and mental health.Smart medical services have the ... In this editorial,I comment on the article by Zhang et al.To emphasize the importance of the topic,I discuss the relationship between the use of smart medical devices and mental health.Smart medical services have the potential to positively influence mental health by providing monitoring,insights,and inter-ventions.However,they also come with challenges that need to be addressed.Understanding the primary purpose for which individuals use these smart tech-nologies is essential to tailoring them to specific mental health needs and prefe-rences. 展开更多
关键词 Smart devices Medical service USAGE PEOPLE RELATIONSHIP Mental health status
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Dynamic changes and driving factors of ecosystem service value(ESV)in the Northeast Forest Belt of China 被引量:1
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作者 Jiao Shi Yujuan Gao Yuyou Zou 《Journal of Forestry Research》 2025年第2期167-186,共20页
The scientific assessment of ecosystem ser-vice value(ESV)plays a critical role in regional ecologi-cal protection and management,rational land use planning,and the establishment of ecological security barriers.The ec... The scientific assessment of ecosystem ser-vice value(ESV)plays a critical role in regional ecologi-cal protection and management,rational land use planning,and the establishment of ecological security barriers.The ecosystem service value of the Northeast Forest Belt from 2005 to 2020 was assessed,focusing on spatial–temporal changes and the driving forces behind these dynamics.Using multi-source data,the equivalent factor method,and geo-graphic detectors,we analyzed natural and socio-economic factors affecting the region.which was crucial for effective ecological conservation and land-use planning.Enhanced the effectiveness of policy formulation and land use plan-ning.The results show that the ESV of the Northeast Forest Belt exhibits an overall increasing trend from 2005 to 2020,with forests and wetlands contributing the most.However,there are significant differences between forest belts.Driven by natural and socio-economic factors,the ESV of forest belts in Heilongjiang and Jilin provinces showed significant growth.In contrast,the ESV of Forest Belts in Liaoning and Inner Mongolia of China remains relatively stable,but the spatial differentiation within these regions is characterized by significant clustering of high-value and low-value areas.Furthermore,climate regulation and hydrological regulation services were identified as the most important ecological functions in the Northeast Forest Belt,contributing greatly to regional ecological stability and human well-being.The ESV in the Northeast Forest Belt is improved during the study period,but the stability of the ecosystem is still chal-lenged by the dual impacts of natural and socio-economic factors.To further optimize regional land use planning and ecological protection policies,it is recommended to prior-itize the conservation of high-ESV areas,enhance ecological restoration efforts for wetlands and forests,and reasonably control the spatial layout of urban expansion and agricul-tural development.Additionally,this study highlights the importance of tailored ecological compensation policies and strategic land-use planning to balance environmental protec-tion and economic growth. 展开更多
关键词 Ecosystem service value(ESV) Northeast Forest Belt of China Equivalent factor method Geographic detectors Driving factors
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