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基于FSSA-ELM的模拟电路故障诊断方法 被引量:1
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作者 陈晓娟 刘禹盟 +1 位作者 曲畅 张昭华 《半导体技术》 北大核心 2024年第1期77-84,共8页
在大规模电路中,模拟电路的故障率高达80%。针对模拟电路故障诊断方法准确率低、耗时长的问题,提出了一种分数阶麻雀搜索算法结合极限学习机(FSSA-ELM)的模拟电路故障诊断方法。利用核主成分分析与局部线性嵌入(KPCA-LLE)联合方式对电... 在大规模电路中,模拟电路的故障率高达80%。针对模拟电路故障诊断方法准确率低、耗时长的问题,提出了一种分数阶麻雀搜索算法结合极限学习机(FSSA-ELM)的模拟电路故障诊断方法。利用核主成分分析与局部线性嵌入(KPCA-LLE)联合方式对电路故障数据进行特征提取,通过分数阶与麻雀搜索算法(SSA)相融合,对极限学习机(ELM)的权重和阈值进行寻优,将提取后的特征数据输入到FSSA-ELM模型中进行训练和测试。T型反馈网络反相比例运算电路诊断实例表明,FSSA-ELM的故障诊断用时相较于SSA-ELM缩短了891 s,单故障诊断准确率可达972%,比SSA-ELM和ELM分别提高了19%和28%;双故障诊断准确率可达95%,分别提高了04%和10%。该故障诊断方法准确率高、耗时短,具有较强的模拟电路故障检测能力。 展开更多
关键词 模拟电路 故障诊断 分数维度 麻雀搜索算法(SSA) 极限学习机(ELM)
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LASEK和TransPRK及FS-LASIK术后角膜屈光力及视觉质量比较
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作者 方薇 孙冉 +1 位作者 张伟 陈旭 《国际眼科杂志》 CAS 2024年第6期870-875,共6页
目的:比较准分子激光上皮下角膜磨镶术(LASEK)、经上皮准分子激光角膜切削术(TransPRK)、飞秒激光制瓣的准分子激光原位角膜磨镶术(FS-LASIK)三种角膜屈光手术术后角膜屈光力及视觉质量。方法:回顾性研究。选取2021-01/2022-12在我院择... 目的:比较准分子激光上皮下角膜磨镶术(LASEK)、经上皮准分子激光角膜切削术(TransPRK)、飞秒激光制瓣的准分子激光原位角膜磨镶术(FS-LASIK)三种角膜屈光手术术后角膜屈光力及视觉质量。方法:回顾性研究。选取2021-01/2022-12在我院择期行角膜屈光手术的232例464眼患者作为研究对象,根据患者选择手术方式不同分为LASEK组70例140眼、TransPRK组76例152眼、FS-LASIK组86例172眼。比较三组患者术前,术后1、3 mo时裸眼视力(UCVA)、视觉质量、生物力学稳定性、泪膜破裂时间(BUT)、泪液分泌试验(SⅠt)及生活质量变化情况。结果:术后1、3 mo三组患者裸眼视力较术前均改善,全角膜总高阶像差、球差、水平彗差、垂直彗差均升高,生物学稳定性均降低(均P<0.05)。术后3 mo, TransPRK组、LASEK组生物学稳定性均高于FS-LASIK组(均P<0.05),TransPRK组生活质量评分较LASEK组及FS-LASIK组高(P<0.05)。手术前后三组患者BUT、SⅠt比较均无差异(均P>0.05)。结论:LASEK、TransPRK、FS-LASIK三种角膜屈光手术治疗屈光不正疗效确切,在改善裸眼视力和提高视觉质量方面结果相似,但TransPRK、LASEK较FS-LASIK具有更稳定的生物力学性能,且TransPRK组在改善患者生活质量方面具有更好的效果。 展开更多
关键词 准分子激光上皮下角膜磨镶术(LASEK) 经上皮准分子激光角膜切削术(TransPRK) 飞秒激光制瓣的准分子激光原位角膜磨镶术(fs-LASIK) 角膜屈光手术 角膜屈光力 视觉质量
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SMILE和WG-FS-LASIK治疗低度无散光近视患者术后早期视觉质量比较
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作者 孔旻 罗武强 +5 位作者 李丽丽 肖信 陈琦 林恩韦 林红 甘宇 《中国临床新医学》 2024年第2期200-205,共6页
目的比较飞秒激光小切口角膜基质内透镜取出术(SMILE)和波前像差引导的准分子激光原位角膜磨镶术(WG-FS-LASIK)治疗低度无散光近视患者术后的早期视觉质量。方法选择2022年3月至6月在广西壮族自治区人民医院视光中心行SMILE治疗的患者15... 目的比较飞秒激光小切口角膜基质内透镜取出术(SMILE)和波前像差引导的准分子激光原位角膜磨镶术(WG-FS-LASIK)治疗低度无散光近视患者术后的早期视觉质量。方法选择2022年3月至6月在广西壮族自治区人民医院视光中心行SMILE治疗的患者15例(30眼,SMILE组),行WG-FS-LASIK治疗的患者15例(30眼,WG-FS-LASIK组)。所有患者术前无散光且最佳矫正视力所需最低球镜度数均≤-3.00 D。于术前和术后1 d、1周、1个月测量视力、全眼像差(慧差、三叶草像差和球差)、客观散射指数(OSI)、调制传递函数截止频率(MTF_(cut-off))、斯特列尔比(SR)、可预测对比度视力(PVA)(包括PVA 100%、PVA 20%、PVA 9%)。比较两组观察指标测量结果。结果两组术后等效球镜、视力情况均较术前显著改善(P<0.05),但两组各时间点比较差异无统计学意义(P>0.05)。两组术后OSI、SR、PVA 9%均较术前显著改善(P<0.05)。WG-FS-LASIK组在术后1 d、1周、1个月的OSI水平均显著低于SMILE组(P<0.05)。在术后1个月,WG-FS-LASIK组PVA 9%显著高于SMILE组(P<0.05)。SMILE组和WG-FS-LASIK组术后慧差均呈先上升后下降的趋势,但WG-FS-LASIK组变化幅度更小,在术后1 d、1周、1个月,WG-FS-LASIK组慧差小于SMILE组,差异有统计学意义(P<0.05)。结论SMILE和WG-FS-LASIK均能提高低度无散光近视患者术后早期视觉质量,但WG-FS-LASIK早期视力恢复更好,且夜间视觉质量改善更优。 展开更多
关键词 飞秒激光小切口角膜基质内透镜取出术 波前像差引导的准分子激光原位角膜磨镶术 低度无散光近视 视觉质量
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基于LightGBM-VIF-MIC-SFS的风电机组故障诊断输入特征选择方法
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作者 马良玉 程东炎 +2 位作者 梁书源 耿妍竹 段新会 《热力发电》 CAS CSCD 北大核心 2024年第1期154-164,共11页
针对风电机组数据采集与监视控制(SCADA)系统数据维数较高、特征冗余、特征相关性高导致风电机组的故障诊断过程存在误差大、分类正确率低的问题,提出一种基于LightGBM-VIF-MIC-SFS的三段式特征选择方法。首先,根据LightGBM实现对所有... 针对风电机组数据采集与监视控制(SCADA)系统数据维数较高、特征冗余、特征相关性高导致风电机组的故障诊断过程存在误差大、分类正确率低的问题,提出一种基于LightGBM-VIF-MIC-SFS的三段式特征选择方法。首先,根据LightGBM实现对所有特征的重要性计算,确定初步特征空间;其次,根据方差膨胀因子(VIF)和最大信息系数(MIC)构建相关性判别阵,据此评估一次筛选中重要性相近的特征,舍弃相似性高的输入特征;最后,使用序列前向搜索法对特征进行第3次处理,逐个输入前2次特征选择获得的特征,保留能提升系统性能的特征,从而实现最终特征的选取。在完成了模型的建立后,使用风电场真实SCADA系统数据进行性能评估,将所提方法与2种对比算法在6个数据集上进行对比,结果显示所提出的LightGBM-VIF-MIC-SFS相较2种对比特征选择算法有显著优势。对所提方法内部的3个模块进行了消融实验,有效验证了所提特征选取方法内部各个模块的有效性以及基于所提方法得到的最优特征空间的合理性及准确性。 展开更多
关键词 风电机组 特征选择 LightGBM 方差膨胀因子 最大信息系数 序列前向搜索
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FS-LASIK Xtra治疗中高度近视患者术后2a的矫正效果 被引量:2
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作者 李金孝 申笛 +3 位作者 周堃 孙西宇 王亚妮 韦伟 《国际眼科杂志》 2024年第2期295-300,共6页
目的:评估FS-LASIK Xtra治疗中高度近视患者术后2 a的矫正效果及角膜形态的稳定性。方法:回顾性病例对照研究。纳入2019-08/2020-08在我院拟行屈光手术的中高度近视合并散光患者30例58眼,根据术前角膜地形图中圆锥角膜筛查相关指数行不... 目的:评估FS-LASIK Xtra治疗中高度近视患者术后2 a的矫正效果及角膜形态的稳定性。方法:回顾性病例对照研究。纳入2019-08/2020-08在我院拟行屈光手术的中高度近视合并散光患者30例58眼,根据术前角膜地形图中圆锥角膜筛查相关指数行不同手术方式,分为FS-LASIK Xtra组15例29眼,FS-LASIK组15例29眼。术前,术后3 mo,1、2 a观察裸眼视力(UCVA)、最佳矫正视力(BCVA)、等效球镜度(SE)及Sirius三维角膜地形图仪测量的不同直径区域(3、5、7 mm)前后表面角膜曲率。结果:两组患者术后不同时间点UCVA均较术前明显提高(均P<0.01),两组间UCVA和SE比较均无差异(P>0.05)。术后2 a,FS-LASIK Xtra组25眼(86%),FS-LASIK组24眼(83%)残余散光为-0.25-0 D。两组实际矫正SE与预矫正SE均呈正相关(均P<0.05)。两组患者术后3 mo,1、2 a不同直径区域(3、5、7 mm)前后表面角膜曲率均较术前有差异(均P<0.05),术后1、2 a FS-LASIK Xtra组角膜直径3、5 mm后表面曲率均高于FS-LASIK组(P<0.05)。结论:FS-LASIK Xtra治疗中高度近视患者有良好的安全性、有效性及可预测性。 展开更多
关键词 飞秒激光辅助准分子激光原位角膜磨镶术(fs-LASIK) 快速角膜交联(Xtra) 近视 角膜曲率
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sub-500 fs宽度2μm光纤激光振荡器研究进展(特邀)
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作者 马晓冉 张恒 +2 位作者 冯天利 李涛 杨克建 《光电技术应用》 2024年第1期1-10,共10页
2μm波段超快激光持续时间短,峰值功率高,光谱范围宽,同时处在大气窗口,多种有机、无机气体分子的吸收峰和人眼安全波段,已广泛应用于生物医疗、激光雷达和非金属材料加工等领域。利用光纤锁模激光振荡器产生2μm波段超快激光是一种最... 2μm波段超快激光持续时间短,峰值功率高,光谱范围宽,同时处在大气窗口,多种有机、无机气体分子的吸收峰和人眼安全波段,已广泛应用于生物医疗、激光雷达和非金属材料加工等领域。利用光纤锁模激光振荡器产生2μm波段超快激光是一种最直接简单的技术方法,具有结构紧凑、光束质量高和成本低等优点。然而,目前关于sub-500 fs的2μm波段的光纤激光振荡器却鲜有报道。基于传统孤子和色散管理孤子两种孤子锁模方式,全面介绍了目前2μm波段sub-500 fs光纤振荡器的研究进展,并总结了实现sub-500 fs脉宽2μm超快激光的关键技术。针对不同的应用领域的具体需求,对2μm超快激光光纤振荡器的未来发展进行展望。 展开更多
关键词 光纤激光器 2μm sub-500 fs 超短脉冲 振荡器
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Evolutionary Neural Architecture Search and Its Applications in Healthcare 被引量:1
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作者 Xin Liu Jie Li +3 位作者 Jianwei Zhao Bin Cao Rongge Yan Zhihan Lyu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期143-185,共43页
Most of the neural network architectures are based on human experience,which requires a long and tedious trial-and-error process.Neural architecture search(NAS)attempts to detect effective architectures without human ... Most of the neural network architectures are based on human experience,which requires a long and tedious trial-and-error process.Neural architecture search(NAS)attempts to detect effective architectures without human intervention.Evolutionary algorithms(EAs)for NAS can find better solutions than human-designed architectures by exploring a large search space for possible architectures.Using multiobjective EAs for NAS,optimal neural architectures that meet various performance criteria can be explored and discovered efficiently.Furthermore,hardware-accelerated NAS methods can improve the efficiency of the NAS.While existing reviews have mainly focused on different strategies to complete NAS,a few studies have explored the use of EAs for NAS.In this paper,we summarize and explore the use of EAs for NAS,as well as large-scale multiobjective optimization strategies and hardware-accelerated NAS methods.NAS performs well in healthcare applications,such as medical image analysis,classification of disease diagnosis,and health monitoring.EAs for NAS can automate the search process and optimize multiple objectives simultaneously in a given healthcare task.Deep neural network has been successfully used in healthcare,but it lacks interpretability.Medical data is highly sensitive,and privacy leaks are frequently reported in the healthcare industry.To solve these problems,in healthcare,we propose an interpretable neuroevolution framework based on federated learning to address search efficiency and privacy protection.Moreover,we also point out future research directions for evolutionary NAS.Overall,for researchers who want to use EAs to optimize NNs in healthcare,we analyze the advantages and disadvantages of doing so to provide detailed guidance,and propose an interpretable privacy-preserving framework for healthcare applications. 展开更多
关键词 Neural architecture search evolutionary computation large-scale multiobjective optimization distributed parallelism healthcare
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Cooperative UAV search strategy based on DMPC-AACO algorithm in restricted communication scenarios 被引量:1
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作者 Shiyuan Chai Zhen Yang +3 位作者 Jichuan Huang Xiaoyang Li Yiyang Zhao Deyun Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期295-311,共17页
Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research pr... Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research problem.In certain mission environments,due to the impact of many interference sources on real-time communication or mission requirements such as the need to implement communication regulations,the mission stages are represented as a dynamic combination of several communication-available and communication-unavailable stages.Furthermore,the data interaction between unmanned aerial vehicles(UAVs)can only be performed in specific communication-available stages.Traditional cooperative search algorithms cannot handle such situations well.To solve this problem,this study constructed a distributed model predictive control(DMPC)architecture for a collaborative control of UAVs and used the Voronoi diagram generation method to re-plan the search areas of all UAVs in real time to avoid repetition of search areas and UAV collisions while improving the search efficiency and safety factor.An attention mechanism ant-colony optimization(AACO)algorithm is proposed for UAV search-control decision planning.The search strategy is adaptively updated by introducing an attention mechanism for regular instruction information,a priori information,and emergent information of the mission to satisfy different search expectations to the maximum extent.Simulation results show that the proposed algorithm achieves better search performance than traditional algorithms in restricted communication constraint scenarios. 展开更多
关键词 Unmanned aerial vehicles(UAV) Cooperative search Restricted communication Mission planning DMPC-AACO
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连翘提取物FS-4体外诱导胃癌细胞SGC-7901凋亡作用的研究
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作者 刘微 江毓桦 +4 位作者 何玉霞 魏梓如 李丹娜 李鑫 金德利 《黑龙江畜牧兽医》 CAS 北大核心 2024年第3期60-65,共6页
为了探讨连翘提取物FS-4体外对胃癌细胞SGC-7901的促凋亡作用,试验采用MTT比色法观察了FS-4对胃癌细胞SGC-7901增殖的抑制情况,AO/EB双荧光染色法和透射电子显微镜观察了细胞凋亡的形态学变化,并通过流式细胞术测定细胞的凋亡率。结果表... 为了探讨连翘提取物FS-4体外对胃癌细胞SGC-7901的促凋亡作用,试验采用MTT比色法观察了FS-4对胃癌细胞SGC-7901增殖的抑制情况,AO/EB双荧光染色法和透射电子显微镜观察了细胞凋亡的形态学变化,并通过流式细胞术测定细胞的凋亡率。结果表明:FS-4对胃癌细胞SGC-7901增殖的抑制作用具有剂量和时间依赖性,其36 h的半数抑制浓度(IC_(50))仅为3.23μg/mL;FS-4作用后细胞均出现典型的凋亡细胞形态;FS-4对细胞的诱导凋亡作用呈现明显的浓度依赖性。说明FS-4可抑制胃癌细胞SGC-7901的增殖并具有诱导其凋亡的作用。 展开更多
关键词 连翘 连翘提取物fs-4 胃癌SGC-7901细胞 细胞凋亡
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Optimal search path planning of UUV in battlefeld ambush scene
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作者 Wei Feng Yan Ma +3 位作者 Heng Li Haixiao Liu Xiangyao Meng Mo Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期541-552,共12页
Aiming at the practical application of Unmanned Underwater Vehicle(UUV)in underwater combat,this paper proposes a battlefield ambush scene with UUV considering ocean current.Firstly,by establishing these mathematical ... Aiming at the practical application of Unmanned Underwater Vehicle(UUV)in underwater combat,this paper proposes a battlefield ambush scene with UUV considering ocean current.Firstly,by establishing these mathematical models of ocean current environment,target movement,and sonar detection,the probability calculation methods of single UUV searching target and multiple UUV cooperatively searching target are given respectively.Then,based on the Hybrid Quantum-behaved Particle Swarm Optimization(HQPSO)algorithm,the path with the highest target search probability is found.Finally,through simulation calculations,the influence of different UUV parameters and target parameters on the target search probability is analyzed,and the minimum number of UUVs that need to be deployed to complete the ambush task is demonstrated,and the optimal search path scheme is obtained.The method proposed in this paper provides a theoretical basis for the practical application of UUV in the future combat. 展开更多
关键词 Battlefield ambush Optimal search path planning UUV path Planning Probability of cooperative search
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Enhanced Differentiable Architecture Search Based on Asymptotic Regularization
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作者 Cong Jin Jinjie Huang +1 位作者 Yuanjian Chen Yuqing Gong 《Computers, Materials & Continua》 SCIE EI 2024年第2期1547-1568,共22页
In differentiable search architecture search methods,a more efficient search space design can significantly improve the performance of the searched architecture,thus requiring people to carefully define the search spa... In differentiable search architecture search methods,a more efficient search space design can significantly improve the performance of the searched architecture,thus requiring people to carefully define the search space with different complexity according to various operations.Meanwhile rationalizing the search strategies to explore the well-defined search space will further improve the speed and efficiency of architecture search.With this in mind,we propose a faster and more efficient differentiable architecture search method,AllegroNAS.Firstly,we introduce a more efficient search space enriched by the introduction of two redefined convolution modules.Secondly,we utilize a more efficient architectural parameter regularization method,mitigating the overfitting problem during the search process and reducing the error brought about by gradient approximation.Meanwhile,we introduce a natural exponential cosine annealing method to make the learning rate of the neural network training process more suitable for the search procedure.Moreover,group convolution and data augmentation are employed to reduce the computational cost.Finally,through extensive experiments on several public datasets,we demonstrate that our method can more swiftly search for better-performing neural network architectures in a more efficient search space,thus validating the effectiveness of our approach. 展开更多
关键词 Differentiable architecture search allegro search space asymptotic regularization natural exponential cosine annealing
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Bridge Bidding via Deep Reinforcement Learning and Belief Monte Carlo Search
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作者 Zizhang Qiu Shouguang Wang +1 位作者 Dan You MengChu Zhou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第10期2111-2122,共12页
Contract Bridge,a four-player imperfect information game,comprises two phases:bidding and playing.While computer programs excel at playing,bidding presents a challenging aspect due to the need for information exchange... Contract Bridge,a four-player imperfect information game,comprises two phases:bidding and playing.While computer programs excel at playing,bidding presents a challenging aspect due to the need for information exchange with partners and interference with communication of opponents.In this work,we introduce a Bridge bidding agent that combines supervised learning,deep reinforcement learning via self-play,and a test-time search approach.Our experiments demonstrate that our agent outperforms WBridge5,a highly regarded computer Bridge software that has won multiple world championships,by a performance of 0.98 IMPs(international match points)per deal over 10000 deals,with a much cost-effective approach.The performance significantly surpasses previous state-of-the-art(0.85 IMPs per deal).Note 0.1 IMPs per deal is a significant improvement in Bridge bidding. 展开更多
关键词 Contract Bridge reinforcement learning search
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FS复合保温外模板系统与挤塑板薄抹灰系统耐久性研究
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作者 曲军辉 刘莉 +4 位作者 赵矗 姜召彩 赵亮 张松浩 王浩旭 《新型建筑材料》 2024年第1期145-149,共5页
FS复合保温外模板系统和挤塑板外保温系统所用保温材料为相同的挤塑板,对FS复合保温外模板系统和挤塑板薄抹灰系统的耐候性试验参照现行国家和行业标准中耐候性试验方法进行研究,通过增加外保温系统耐候性试验中热雨循环和热冷循环的循... FS复合保温外模板系统和挤塑板外保温系统所用保温材料为相同的挤塑板,对FS复合保温外模板系统和挤塑板薄抹灰系统的耐候性试验参照现行国家和行业标准中耐候性试验方法进行研究,通过增加外保温系统耐候性试验中热雨循环和热冷循环的循环次数,同时设置系统耐候性中的热雨循环和热冷循环交替进行,更加符合现实生活中工程现场的实际工况。试验结果表明,随着增加外保温系统耐候性试验中热雨循环和热冷循环的循环次数,外保温系统的耐久性年限也随之增加,但二者并非线性关系。 展开更多
关键词 保温隔热 保温检测 fs复合保温外模板 耐候性 外墙外保温系统
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A Lightweight, Searchable, and Controllable EMR Sharing Scheme
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作者 Xiaohui Yang Peiyin Zhao 《Computers, Materials & Continua》 SCIE EI 2024年第4期1521-1538,共18页
Electronic medical records (EMR) facilitate the sharing of medical data, but existing sharing schemes suffer fromprivacy leakage and inefficiency. This article proposes a lightweight, searchable, and controllable EMR ... Electronic medical records (EMR) facilitate the sharing of medical data, but existing sharing schemes suffer fromprivacy leakage and inefficiency. This article proposes a lightweight, searchable, and controllable EMR sharingscheme, which employs a large attribute domain and a linear secret sharing structure (LSSS), the computationaloverhead of encryption and decryption reaches a lightweight constant level, and supports keyword search andpolicy hiding, which improves the high efficiency of medical data sharing. The dynamic accumulator technologyis utilized to enable data owners to flexibly authorize or revoke the access rights of data visitors to the datato achieve controllability of the data. Meanwhile, the data is re-encrypted by Intel Software Guard Extensions(SGX) technology to realize resistance to offline dictionary guessing attacks. In addition, blockchain technology isutilized to achieve credible accountability for abnormal behaviors in the sharing process. The experiments reflectthe obvious advantages of the scheme in terms of encryption and decryption computation overhead and storageoverhead, and theoretically prove the security and controllability in the sharing process, providing a feasible solutionfor the safe and efficient sharing of EMR. 展开更多
关键词 LIGHTWEIGHT keyword search large attribute domain CONTROLLABILITY blockchain
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基于改进SFS算法的锚杆钻臂参数整定研究
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作者 陶磊 陈岳 +2 位作者 王宏伟 李超 姚林虎 《煤炭工程》 北大核心 2024年第4期218-224,共7页
针对锚杆钻臂井下自动控制过程中存在的环境恶劣、地质复杂等特殊工况,需着重考虑PID的参数选取,为此采用随机分形搜索算法(SFS)对PID参数进行整定。由于随机分形搜索算法存在局部搜索能力不足、易陷入局部最优等问题,在面对机械臂待整... 针对锚杆钻臂井下自动控制过程中存在的环境恶劣、地质复杂等特殊工况,需着重考虑PID的参数选取,为此采用随机分形搜索算法(SFS)对PID参数进行整定。由于随机分形搜索算法存在局部搜索能力不足、易陷入局部最优等问题,在面对机械臂待整定参数多及参数间耦合严重时,其整定效果不佳。因此,引入混沌初始化、正余弦策略、自适应K值选取策略以提高算法的局部搜索能力以及全局搜索速度;采用柯西、差分定向变异策略使算法跳出局部最优。通过标准测试函数测试表明改进后的随机分形搜索算法收敛速度及精度均有一定提高。最后通过锚杆钻臂参数整定仿真实验表明:改进后随机分形搜索算法整定的PID参数总体适应度值提高21%;各关节的量化指标表示改进后随机分形搜索算法跳出了局部最优,提高了整体寻优精度与速度。 展开更多
关键词 锚杆钻臂 参数整定 随机分形搜索算法 PID控制
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Privacy-Preserving Multi-Keyword Fuzzy Adjacency Search Strategy for Encrypted Graph in Cloud Environment
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作者 Bin Wu Xianyi Chen +5 位作者 Jinzhou Huang Caicai Zhang Jing Wang Jing Yu Zhiqiang Zhao Zhuolin Mei 《Computers, Materials & Continua》 SCIE EI 2024年第3期3177-3194,共18页
In a cloud environment,outsourced graph data is widely used in companies,enterprises,medical institutions,and so on.Data owners and users can save costs and improve efficiency by storing large amounts of graph data on... In a cloud environment,outsourced graph data is widely used in companies,enterprises,medical institutions,and so on.Data owners and users can save costs and improve efficiency by storing large amounts of graph data on cloud servers.Servers on cloud platforms usually have some subjective or objective attacks,which make the outsourced graph data in an insecure state.The issue of privacy data protection has become an important obstacle to data sharing and usage.How to query outsourcing graph data safely and effectively has become the focus of research.Adjacency query is a basic and frequently used operation in graph,and it will effectively promote the query range and query ability if multi-keyword fuzzy search can be supported at the same time.This work proposes to protect the privacy information of outsourcing graph data by encryption,mainly studies the problem of multi-keyword fuzzy adjacency query,and puts forward a solution.In our scheme,we use the Bloom filter and encryption mechanism to build a secure index and query token,and adjacency queries are implemented through indexes and query tokens on the cloud server.Our proposed scheme is proved by formal analysis,and the performance and effectiveness of the scheme are illustrated by experimental analysis.The research results of this work will provide solid theoretical and technical support for the further popularization and application of encrypted graph data processing technology. 展开更多
关键词 PRIVACY-PRESERVING adjacency query multi-keyword fuzzy search encrypted graph
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Spatial search weighting information contained in cell velocity distribution
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作者 马一凯 李娜 陈唯 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期522-528,共7页
Cell migration plays a significant role in physiological and pathological processes.Understanding the characteristics of cell movement is crucial for comprehending biological processes such as cell functionality,cell ... Cell migration plays a significant role in physiological and pathological processes.Understanding the characteristics of cell movement is crucial for comprehending biological processes such as cell functionality,cell migration,and cell–cell interactions.One of the fundamental characteristics of cell movement is the specific distribution of cell speed,containing valuable information that still requires comprehensive understanding.This article investigates the distribution of mean velocities along cell trajectories,with a focus on optimizing the efficiency of cell food search in the context of the entire colony.We confirm that the specific velocity distribution in the experiments corresponds to an optimal search efficiency when spatial weighting is considered.The simulation results indicate that the distribution of average velocity does not align with the optimal search efficiency when employing average spatial weighting.However,when considering the distribution of central spatial weighting,the specific velocity distribution in the experiment is shown to correspond to the optimal search efficiency.Our simulations reveal that for any given distribution of average velocity,a specific central spatial weighting can be identified among the possible central spatial weighting that aligns with the optimal search strategy.Additionally,our work presents a method for determining the spatial weights embedded in the velocity distribution of cell movement.Our results have provided new avenues for further investigation of significant topics,such as relationship between cell behavior and environmental conditions throughout their evolutionary history,and how cells achieve collective cooperation through cell-cell communication. 展开更多
关键词 cell migration foraging efficiency random walk spatial search weight
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Even Search in a Promising Region for Constrained Multi-Objective Optimization
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作者 Fei Ming Wenyin Gong Yaochu Jin 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期474-486,共13页
In recent years, a large number of approaches to constrained multi-objective optimization problems(CMOPs) have been proposed, focusing on developing tweaked strategies and techniques for handling constraints. However,... In recent years, a large number of approaches to constrained multi-objective optimization problems(CMOPs) have been proposed, focusing on developing tweaked strategies and techniques for handling constraints. However, an overly finetuned strategy or technique might overfit some problem types,resulting in a lack of versatility. In this article, we propose a generic search strategy that performs an even search in a promising region. The promising region, determined by obtained feasible non-dominated solutions, possesses two general properties.First, the constrained Pareto front(CPF) is included in the promising region. Second, as the number of feasible solutions increases or the convergence performance(i.e., approximation to the CPF) of these solutions improves, the promising region shrinks. Then we develop a new strategy named even search,which utilizes the non-dominated solutions to accelerate convergence and escape from local optima, and the feasible solutions under a constraint relaxation condition to exploit and detect feasible regions. Finally, a diversity measure is adopted to make sure that the individuals in the population evenly cover the valuable areas in the promising region. Experimental results on 45 instances from four benchmark test suites and 14 real-world CMOPs have demonstrated that searching evenly in the promising region can achieve competitive performance and excellent versatility compared to 11 most state-of-the-art methods tailored for CMOPs. 展开更多
关键词 Constrained multi-objective optimization even search evolutionary algorithms promising region real-world problems
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Database Search Behaviors: Insight from a Survey of Information Retrieval Practices
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作者 Babita Trivedi Brijender Dahiya +2 位作者 Anjali Maan Rajesh Giri Vinod Prasad 《Intelligent Information Management》 2024年第5期195-218,共24页
This study examines the database search behaviors of individuals, focusing on gender differences and the impact of planning habits on information retrieval. Data were collected from a survey of 198 respondents, catego... This study examines the database search behaviors of individuals, focusing on gender differences and the impact of planning habits on information retrieval. Data were collected from a survey of 198 respondents, categorized by their discipline, schooling background, internet usage, and information retrieval preferences. Key findings indicate that females are more likely to plan their searches in advance and prefer structured methods of information retrieval, such as using library portals and leading university websites. Males, however, tend to use web search engines and self-archiving methods more frequently. This analysis provides valuable insights for educational institutions and libraries to optimize their resources and services based on user behavior patterns. 展开更多
关键词 Information Retrieval Database search User Behavior Patterns
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Research on Evacuation Path Planning Based on Improved Sparrow Search Algorithm
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作者 Xiaoge Wei Yuming Zhang +2 位作者 Huaitao Song Hengjie Qin Guanjun Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1295-1316,共22页
Reducing casualties and property losses through effective evacuation route planning has been a key focus for researchers in recent years.As part of this effort,an enhanced sparrow search algorithm(MSSA)was proposed.Fi... Reducing casualties and property losses through effective evacuation route planning has been a key focus for researchers in recent years.As part of this effort,an enhanced sparrow search algorithm(MSSA)was proposed.Firstly,the Golden Sine algorithm and a nonlinear weight factor optimization strategy were added in the discoverer position update stage of the SSA algorithm.Secondly,the Cauchy-Gaussian perturbation was applied to the optimal position of the SSA algorithm to improve its ability to jump out of local optima.Finally,the local search mechanism based on the mountain climbing method was incorporated into the local search stage of the SSA algorithm,improving its local search ability.To evaluate the effectiveness of the proposed algorithm,the Whale Algorithm,Gray Wolf Algorithm,Improved Gray Wolf Algorithm,Sparrow Search Algorithm,and MSSA Algorithm were employed to solve various test functions.The accuracy and convergence speed of each algorithm were then compared and analyzed.The results indicate that the MSSA algorithm has superior solving ability and stability compared to other algorithms.To further validate the enhanced algorithm’s capabilities for path planning,evacuation experiments were conducted using different maps featuring various obstacle types.Additionally,a multi-exit evacuation scenario was constructed according to the actual building environment of a teaching building.Both the sparrow search algorithm and MSSA algorithm were employed in the simulation experiment for multiexit evacuation path planning.The findings demonstrate that the MSSA algorithm outperforms the comparison algorithm,showcasing its greater advantages and higher application potential. 展开更多
关键词 Sparrow search algorithm optimization and improvement function test set evacuation path planning
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