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Corneal collagen cross-linking in patients with keratoconus from the Dresden protocol to customized solutions:theoretical basis
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作者 Ciro Caruso Luca D’Andrea +4 位作者 Mario Troisi Michele Rinaldi Raffaele Piscopo Salvatore Troisi Ciro Costagliola 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期951-962,共12页
Keratoconus is an ectatic condition characterized by gradual corneal thinning,corneal protrusion,progressive irregular astigmatism,corneal fibrosis,and visual impairment.The therapeutic options regarding improvement o... Keratoconus is an ectatic condition characterized by gradual corneal thinning,corneal protrusion,progressive irregular astigmatism,corneal fibrosis,and visual impairment.The therapeutic options regarding improvement of visual function include glasses or soft contact lenses correction for initial stages,gas-permeable rigid contact lenses,scleral lenses,implantation of intrastromal corneal ring or corneal transplants for most advanced stages.In keratoconus cases showing disease progression corneal collagen crosslinking(CXL)has been proven to be an effective,minimally invasive and safe procedure.CXL consists of a photochemical reaction of corneal collagen by riboflavin stimulation with ultraviolet A radiation,resulting in stromal crosslinks formation.The aim of this review is to carry out an examination of CXL methods based on theoretical basis and mathematical models,from the original Dresden protocol to the most recent developments in the technique,reporting the changes proposed in the last 15y and examining the advantages and disadvantages of the various treatment protocols.Finally,the limits of non-standardized methods and the perspectives offered by a customization of the treatment are highlighted. 展开更多
关键词 corneal collagen cross linking KERATOCONUS custom fast protocol Dresden protocol lambert-beer law Bunsen-roscoe law
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SHEL:a semantically enhanced hardware-friendly entity linking method
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作者 亓东林 CHEN Shudong +2 位作者 DU Rong TONG Da YU Yong 《High Technology Letters》 EI CAS 2024年第1期13-22,共10页
With the help of pre-trained language models,the accuracy of the entity linking task has made great strides in recent years.However,most models with excellent performance require fine-tuning on a large amount of train... With the help of pre-trained language models,the accuracy of the entity linking task has made great strides in recent years.However,most models with excellent performance require fine-tuning on a large amount of training data using large pre-trained language models,which is a hardware threshold to accomplish this task.Some researchers have achieved competitive results with less training data through ingenious methods,such as utilizing information provided by the named entity recognition model.This paper presents a novel semantic-enhancement-based entity linking approach,named semantically enhanced hardware-friendly entity linking(SHEL),which is designed to be hardware friendly and efficient while maintaining good performance.Specifically,SHEL's semantic enhancement approach consists of three aspects:(1)semantic compression of entity descriptions using a text summarization model;(2)maximizing the capture of mention contexts using asymmetric heuristics;(3)calculating a fixed size mention representation through pooling operations.These series of semantic enhancement methods effectively improve the model's ability to capture semantic information while taking into account the hardware constraints,and significantly improve the model's convergence speed by more than 50%compared with the strong baseline model proposed in this paper.In terms of performance,SHEL is comparable to the previous method,with superior performance on six well-established datasets,even though SHEL is trained using a smaller pre-trained language model as the encoder. 展开更多
关键词 entity linking(EL) pre-trained models knowledge graph text summarization semantic enhancement
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稀疏图的r-动态染色
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作者 卜月华 王晓燕 朱洪国 《浙江师范大学学报(自然科学版)》 CAS 2024年第2期150-156,共7页
通过分析极小反例的结构性质,运用权转移的方法,研究了对于mad(G)<14/5的稀疏图G的r-动态染色数,证明了对于满足mad(G)<14/5的图G,若r≥9,则χr(G)≤r+2.研究结果推广了稀疏图r-动态染色的已知结果.
关键词 稀疏图 r-动态染色 最大平均度 权转移
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一种MAKLINK图多节点链路建模的路径规划研究
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作者 孙培刚 张全禹 许春和 《电子设计工程》 2024年第4期140-143,148,共5页
针对传统MAKLINK图规划路径线路改变时,其最优化路径易与环境约束条件冲突的问题,提出了在MAKLINK图中各链路上增加节点数目的方法,以提高系统建模的适应性和鲁棒性。设计的多节点链路通过dijkstra算法得到更为理想的次优化路径,由蚁群... 针对传统MAKLINK图规划路径线路改变时,其最优化路径易与环境约束条件冲突的问题,提出了在MAKLINK图中各链路上增加节点数目的方法,以提高系统建模的适应性和鲁棒性。设计的多节点链路通过dijkstra算法得到更为理想的次优化路径,由蚁群算法进行迭代计算获得最优化路径,实现了在保证路径适应度的前提下,提高优化路径对环境约束条件的适应性。实验结果表明,与基本MAKLINK图路径规划算法相比,多节点链路的建模路径规划算法可有效提高次优路径的建模精度,最优路径的适应度值较单节点链路减小了1.43%,具有一定的建模优势。 展开更多
关键词 MAKlink 多节点链路 DIJKSTRA算法 蚁群算法
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面向Link16的QualNet与虚拟机信息交互接口设计与实现
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作者 杨昊伟 龚鹏 +4 位作者 张继豪 王卫东 唐飞喜 周子骄 张广为 《兵工学报》 EI CAS CSCD 北大核心 2024年第4期1186-1195,共10页
Link16是美国国防部采用的高速视距战术数据链,广泛应用于美国海军、联合部队和北约部队,针对其开展测试评估具有重要军事意义。通过硬件在环技术将Link16实物设备接入到仿真测试中,可有效提高测试结果的真实性和准确性。然而当测试场... Link16是美国国防部采用的高速视距战术数据链,广泛应用于美国海军、联合部队和北约部队,针对其开展测试评估具有重要军事意义。通过硬件在环技术将Link16实物设备接入到仿真测试中,可有效提高测试结果的真实性和准确性。然而当测试场景需要进行实物设备组网测试时,仍会带来成本问题。为此,提出一种面向QualNet MAC层的Link16专属模型以及与之匹配的虚拟机信息交互接口。该模型可高逼真模拟Link16通信行为,实现Link16节点竞争接入、时隙划分、NPG分组等功能。并基于数据分布式服务实现了虚拟机交互接口,将运行在虚拟机的Link16设备模型接入QualNet测试场景。实验测试结果表明,所设计模型具有较高真实性和准确性且接口引入延时不超过1 ms,为大规模数据链网络测试提供一种新方法。 展开更多
关键词 交互接口 link16数据链 虚拟机 QualNet MAC层 网络仿真
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血清miR-590联合粪便钙卫蛋白对溃疡性结肠炎的诊断价值及其与内镜下疾病活动度的相关性
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作者 路敏敏 王俊 +4 位作者 孙振林 董浩 李超 李娜 薛春霞 《国际消化病杂志》 CAS 2024年第3期196-199,共4页
目的 探究血清miR-590联合粪便钙卫蛋白(FC)对溃疡性结肠炎(UC)的诊断价值及与内镜下疾病活动度的相关性。方法 选择2021年1月至2023年2月滨州市人民医院消化内科收治的84例UC患者设为研究组,另选择同期在该院体检的56名健康志愿者设为... 目的 探究血清miR-590联合粪便钙卫蛋白(FC)对溃疡性结肠炎(UC)的诊断价值及与内镜下疾病活动度的相关性。方法 选择2021年1月至2023年2月滨州市人民医院消化内科收治的84例UC患者设为研究组,另选择同期在该院体检的56名健康志愿者设为对照组。分别采用实时荧光定量PCR法和ELISA法检测2组的血清miR-590和FC水平。采用Pearson相关性分析法探究血清miR-590与溃疡性结肠炎内镜下严重程度指数(UCEIS)的相关性,采用Spearman秩相关性分析法探究FC与UCEIS的相关性。采用ROC曲线分析血清miR-590联合FC对UC的诊断价值及与内镜下疾病活动度的相关性。结果 研究组的血清miR-590表达水平较对照组显著降低,FC水平较对照组显著升高,差异均有统计学意义(P均<0.05)。血清miR-590联合FC诊断UC的敏感度、特异度、曲线下面积(AUC)分别为95.48%、76.85%、0.914,两者联合的诊断效能均高于单一指标(P均<0.05)。与缓解期UC患者相比,活动期UC患者的血清miR-590表达水平较低,且血清miR-590表达水平与内镜下疾病活动度呈负相关(P<0.05)。与缓解期UC患者相比,活动期UC患者的FC水平较高,且FC水平与内镜下疾病活动度呈正相关(P<0.05)。UC患者的血清miR-590表达水平与UCEIS评分呈显著负相关(r=-0.791,P=0.000),FC水平与UCEIS评分呈显著正相关(r=0.884,P=0.000)。血清miR-590联合FC评估UC内镜下疾病活动度的敏感度、特异度、AUC分别为97.31%、78.42%、0.946,两者联合的评估效能均高于单一指标(P均<0.05)。结论 血清miR-590联合FC有助于提高UC诊断的敏感度,并可作为辅助指标评估内镜下疾病活动度,具有临床推广价值。 展开更多
关键词 溃疡性结肠炎 mi r-590 粪便钙卫蛋白 诊断价值 内镜下疾病活动度
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具有中间幂等元的r-宽大半群
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作者 白雪娜 宫春梅 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期1-7,共7页
讨论了r-宽大半群上的中间幂等元及其相关幂等元的性质.借此,证明了具有弱型A可乘中间幂等元u的r-宽大半群是自然序r-宽大半群,其中u是最大幂等元.
关键词 r-宽大半群 中间幂等元 自然序 弱型A半群
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一种改进的Link16信号检测方法
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作者 薛燕 高春芳 杨欣 《现代雷达》 CSCD 北大核心 2024年第1期39-44,共6页
直接序列扩频、高速跳频与跳时相结合的技术,造成了对Link16信号的检测具有相当的难度。文中针对突发Link16信号脉冲宽度强规律性,借鉴双滑动窗算法在突发信号检测上的应用,提出了改进后基于相关处理的双滑动窗Link16信号检测方法,该方... 直接序列扩频、高速跳频与跳时相结合的技术,造成了对Link16信号的检测具有相当的难度。文中针对突发Link16信号脉冲宽度强规律性,借鉴双滑动窗算法在突发信号检测上的应用,提出了改进后基于相关处理的双滑动窗Link16信号检测方法,该方法可实现复杂电磁环境下对Link16信号的高灵敏度、高概率检测,同时正确估算出脉宽、码速率等参数信息。仿真实验数据验证了理论分析的正确性和所述方法的有效性,相较于其他Link16信号检测方法,改进后的基于相关处理的双滑动窗检测算法明显提高了在低信噪比下对Link16信号的检测能力。 展开更多
关键词 link16信号 双窗滑动相关 突发信号检测
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黄花苜蓿MfMYB3R-3基因克隆及结构与功能的生物信息学分析
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作者 柴华 杨曌 +4 位作者 申忠宝 李莎莎 王晓龙 徐艳霞 吴玥 《种子》 北大核心 2024年第5期33-39,共7页
MYB转录因子是植物中分布最广的转录因子家族之一,在植物响应生物及非生物胁迫,调控逆境胁迫相关基因表达方面起着重要的作用。本研究基于黄花苜蓿转录组数据,鉴定和克隆了黄花苜蓿MfMYB3R-3基因,并进行了生物信息学分析。结果表明,MfMY... MYB转录因子是植物中分布最广的转录因子家族之一,在植物响应生物及非生物胁迫,调控逆境胁迫相关基因表达方面起着重要的作用。本研究基于黄花苜蓿转录组数据,鉴定和克隆了黄花苜蓿MfMYB3R-3基因,并进行了生物信息学分析。结果表明,MfMYB3R-3基因CDS区长1701 bp,编码566个氨基酸,具有SANT保守结构域,为MYB3R型转录因子;MfMYB3R-3蛋白化学分子式为C_(2690)H_(4314)N_(796)O_(873)S_(20),理论等电点为8.75,该蛋白是亲水性不稳定偏碱性非分泌蛋白,不具有信号肽,无跨膜结构,亚细胞定位预测在细胞核。系统进化分析发现,黄花苜蓿MfMYB3R-3蛋白与蒺藜苜蓿的MYB3R-3的亲缘关系最近。 展开更多
关键词 黄花苜蓿 MfMYB3r-3基因 克隆 生物信息学
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基于GS1 Digital Link的Web编码构建与案例应用
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作者 王少然 李小英 韩英玉 《保鲜与加工》 CAS 北大核心 2024年第4期49-53,60,共6页
为探索GS1 Digital Link技术在产品物流中的应用潜力,分析研究了GS1系统和GS1 Digital Link的基本结构、编码特点以及技术优势,充分利用GS1 Digital Link技术可以为产品从源头到零售整个物流过程提供相关对象的Web地址编码的特点,以鲜... 为探索GS1 Digital Link技术在产品物流中的应用潜力,分析研究了GS1系统和GS1 Digital Link的基本结构、编码特点以及技术优势,充分利用GS1 Digital Link技术可以为产品从源头到零售整个物流过程提供相关对象的Web地址编码的特点,以鲜活大闸蟹物流过程为例,构建了基于GS1 Digital Link的鲜活大闸蟹Web编码,为实现产品营销与追溯提供了标准化、动态化、多样化的编码数据支撑。 展开更多
关键词 GS1 GS1 Digital link 标准化 物流 编码 标识
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Time Transfer in a 1839-km Telecommunication Fiber Link Demonstrating a Picosecond-Scale Stability
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作者 郭新兴 侯丙安 +5 位作者 刘博 杨凡 孔维成 刘涛 董瑞芳 张首刚 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第6期49-53,共5页
An implementation of high-precision time transfer over a 1839-km field fiber loop back link between two provincial capitals of China,Xi’an and Taiyuan,is reported.Time transfer stabilities of 6.5 ps at averaging time... An implementation of high-precision time transfer over a 1839-km field fiber loop back link between two provincial capitals of China,Xi’an and Taiyuan,is reported.Time transfer stabilities of 6.5 ps at averaging time of 1 s and 4.6 ps at 40000 s were achieved.The uncertainty for the time transfer system was evaluated,showing a budget of 56.2 ps.These results stand for a significant milestone in achieving high-precision time transfer over a field fiber link spanning thousands of kilometers,signifying a record-breaking achievement for the real-field time transfer in both stability and distance,which paves the way for constructing the nationwide high-precision time service via fiber network. 展开更多
关键词 FIBER NATIONWIDE link
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Robust free-space optical frequency transfer in time-varying link distances conditions
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作者 童周 刘雷 +6 位作者 王家亮 操前 金志成 应康 韩申生 韩正甫 桂有珍 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期271-276,共6页
Future inter-satellite clock comparison on high orbit will require optical time and frequency transmission technology between moving objects.Here,we demonstrate robust optical frequency transmission under the conditio... Future inter-satellite clock comparison on high orbit will require optical time and frequency transmission technology between moving objects.Here,we demonstrate robust optical frequency transmission under the condition of variable link distance.This variable link is accomplished by the relative motion of a single telescope fixed on the experimental platform to a corner-cube reflector(CCR)installed on a sliding guide.Two acousto–optic modulators with different frequencies are used to separate forward signal from backward signal.With active phase noise suppression,when the CCR moves back and forth at a constant velocity of 20 cm/s and an acceleration of 20 cm/s^(2),we achieve the best frequency stability of 1.9×10^(-16) at 1 s and 7.9×10^(-19) at 1000 s indoors.This work paves the way for future studying optical frequency transfer between ultra-high-orbit satellites. 展开更多
关键词 FREE-SPACE optical frequency transfer variable link distance
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Dilation,discrimination and Uhlmann's theorem of link products of quantum channels
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作者 雷强 操刘桁 +1 位作者 Asutosh Kumar 武俊德 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期201-206,共6页
We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-l... We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-linking each quantum channel n times as n grows.We also find that the maximum value of Uhlmann's theorem can be achieved for diagonal channels. 展开更多
关键词 quantum channels link products Stinespring dilation theorem Uhlmann's theorem
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Coherent optical frequency transfer via 972-km fiber link
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作者 邓雪 张翔 +8 位作者 臧琦 焦东东 王丹 刘杰 高静 许冠军 董瑞芳 刘涛 张首刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期277-282,共6页
We demonstrate coherent optical frequency dissemination over a distance of 972 km by cascading two spans where the phase noise is passively compensated for.Instead of employing a phase discriminator and a phase lockin... We demonstrate coherent optical frequency dissemination over a distance of 972 km by cascading two spans where the phase noise is passively compensated for.Instead of employing a phase discriminator and a phase locking loop in the conventional active phase control scheme,the passive phase noise cancellation is realized by feeding double-trip beat-note frequency to the driver of the acoustic optical modulator at the local site.This passive scheme exhibits fine robustness and reliability,making it suitable for long-distance and noisy fiber links.An optical regeneration station is used in the link for signal amplification and cascaded transmission.The phase noise cancellation and transfer instability of the 972-km link is investigated,and transfer instability of 1.1×10^(-19)at 10^(4)s is achieved.This work provides a promising method for realizing optical frequency distribution over thousands of kilometers by using fiber links. 展开更多
关键词 optical frequency transfer fiber link phase noise cancellation
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Layered Coded Cache Placement and Cooperative Delivery with Sharing Links in Satellite-Terrestrial Integrated Networks
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作者 Gu Shushi Chen Zihan +2 位作者 Wu Yaonan Zhang Qinyu Wang Ye 《China Communications》 SCIE CSCD 2024年第3期217-229,共13页
Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content deliver... Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content delivery over the seamless global coverage area. However, the on-board supportable resources of a single satellite are extremely limited and lack of interaction with others. In this paper, we design a network model with two-layered cache deployment, i.e., satellite layer and ground base station layer, and two types of sharing links, i.e., terrestrial-satellite sharing(TSS) links and inter-satellite sharing(ISS) links, to enhance the capability of cooperative delivery over STINs. Thus, we use rateless codes for the content divided-packet transmission, and derive the total energy efficiency(EE) in the whole transmission procedure, which is defined as the ratio of traffic offloading and energy consumption. We formulate two optimization problems about maximizing EE in different sharing scenarios(only TSS and TSS-ISS),and propose two optimized algorithms to obtain the optimal content placement matrixes, respectively.Simulation results demonstrate that, enabling sharing links with optimized cache placement have more than 2 times improvement of EE performance than other traditional placement schemes. Particularly, TSS-ISS schemes have the higher EE performance than only TSS schemes under the conditions of enough number of satellites and smaller inter-satellite distances. 展开更多
关键词 coded content placement cooperative delivery energy efficiency sharing links STINs
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基于FANUC系统I/O LINK轴的一种新型垂度补偿功能
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作者 张韬 谢丽 李兴迪 《机电工程技术》 2024年第1期95-98,共4页
由于自身重力的原因,配置多附件头的数控落地镗铣床的滑枕在长行程伸出时会在垂直方向上产生相应的形变。为降低由于形变引入的误差对加工精度所造成的影响,以FANUC 0i MF数控系统作为控制平台,结合I/O LINK轴的应用,提出了一种不使用FA... 由于自身重力的原因,配置多附件头的数控落地镗铣床的滑枕在长行程伸出时会在垂直方向上产生相应的形变。为降低由于形变引入的误差对加工精度所造成的影响,以FANUC 0i MF数控系统作为控制平台,结合I/O LINK轴的应用,提出了一种不使用FANUC系统“平直度补偿”功能的补偿方案。运用区间补偿的思想,将整个滑枕的行程划分为多个运动区间,以误差测量实验的方式将滑枕垂向的误差转换为补偿轴的坐标并得出补偿数据,通过PLC程序将补偿轴坐标与滑枕实际位置进行匹配,以同一运动区间调用固定补偿值的方式对滑枕进行线性补偿。通过对不同的附件头创建不同的补偿程序,并使用K地址调用相应补偿数据的方式,排除了不同补偿数据间相互干扰的隐患。所提方案在实际机床中的应用结果表明:其补偿效果可达到与FANUC系统“平直度补偿”功能相一致的水平。 展开更多
关键词 滑枕 I/O link 补偿 PLC程序 区间
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Underwater Image Classification Based on EfficientnetB0 and Two-Hidden-Layer Random Vector Functional Link
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作者 ZHOU Zhiyu LIU Mingxuan +2 位作者 JI Haodong WANG Yaming ZHU Zefei 《Journal of Ocean University of China》 CAS CSCD 2024年第2期392-404,共13页
The ocean plays an important role in maintaining the equilibrium of Earth’s ecology and providing humans access to a wealth of resources.To obtain a high-precision underwater image classification model,we propose a c... The ocean plays an important role in maintaining the equilibrium of Earth’s ecology and providing humans access to a wealth of resources.To obtain a high-precision underwater image classification model,we propose a classification model that combines an EfficientnetB0 neural network and a two-hidden-layer random vector functional link network(EfficientnetB0-TRVFL).The features of underwater images were extracted using the EfficientnetB0 neural network pretrained via ImageNet,and a new fully connected layer was trained on the underwater image dataset using the transfer learning method.Transfer learning ensures the initial performance of the network and helps in the development of a high-precision classification model.Subsequently,a TRVFL was proposed to improve the classification property of the model.Net construction of the two hidden layers exhibited a high accuracy when the same hidden layer nodes were used.The parameters of the second hidden layer were obtained using a novel calculation method,which reduced the outcome error to improve the performance instability caused by the random generation of parameters of RVFL.Finally,the TRVFL classifier was used to classify features and obtain classification results.The proposed EfficientnetB0-TRVFL classification model achieved 87.28%,74.06%,and 99.59%accuracy on the MLC2008,MLC2009,and Fish-gres datasets,respectively.The best convolutional neural networks and existing methods were stacked up through box plots and Kolmogorov-Smirnov tests,respectively.The increases imply improved systematization properties in underwater image classification tasks.The image classification model offers important performance advantages and better stability compared with existing methods. 展开更多
关键词 underwater image classification EfficientnetB0 random vector functional link convolutional neural network
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Fault diagnosis method of link control system for gravitational wave detection
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作者 GAO Ai XU Shengnan +2 位作者 ZHAO Zichen SHANG Haibin XU Rui 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期922-931,共10页
To maintain the stability of the inter-satellite link for gravitational wave detection,an intelligent learning monitoring and fast warning method of the inter-satellite link control system failure is proposed.Differen... To maintain the stability of the inter-satellite link for gravitational wave detection,an intelligent learning monitoring and fast warning method of the inter-satellite link control system failure is proposed.Different from the traditional fault diagnosis optimization algorithms,the fault intelligent learning method pro-posed in this paper is able to quickly identify the faults of inter-satellite link control system despite the existence of strong cou-pling nonlinearity.By constructing a two-layer learning network,the method enables efficient joint diagnosis of fault areas and fault parameters.The simulation results show that the average identification time of the system fault area and fault parameters is 0.27 s,and the fault diagnosis efficiency is improved by 99.8%compared with the traditional algorithm. 展开更多
关键词 large scale multi-satellite formation gravitational wave detection laser link monitoring fault diagnosis deep learning
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电动汽车电控液压制动系统CarSim/Simulink联合仿真研究 被引量:1
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作者 洪诚 李琤 《汽车实用技术》 2024年第5期52-58,共7页
针对某款国产电动汽车的电控液压制动系统,文章基于滑移率的比例-积分-微分(PID)控制提出了防抱死制动系统(ABS)模型,以改善车辆制动性能,提高在对开路面上的制动有效性和安全性。首先,使用Simulink软件建立液压电控制动系统的动力学模... 针对某款国产电动汽车的电控液压制动系统,文章基于滑移率的比例-积分-微分(PID)控制提出了防抱死制动系统(ABS)模型,以改善车辆制动性能,提高在对开路面上的制动有效性和安全性。首先,使用Simulink软件建立液压电控制动系统的动力学模型;然后,基于滑移率设计PID控制器,并通过1/4车辆模型验证其有效性;最后,利用S函数将ABS控制器的Simulink模型输入CarSim平台中,开展CarSim/Simulink双平台联合控制仿真。结果表明,基于滑移率的PID控制的ABS对比无ABS的车辆,制动性能更加优越,在对开路面上制动稳定性更加明显。 展开更多
关键词 ABS 电动汽车 电控液压 汽车动力学 CarSim/Simulink联合仿真 制动性能
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miR-485-5p靶向氧连接的N-乙酰氨基葡萄糖转移酶抑制前列腺癌细胞的增殖、迁移与侵袭
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作者 胡东来 赵梓岐 +3 位作者 李元 杨丽 雷艳丽 楚元奎 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2024年第2期258-268,共11页
前列腺癌是男性生殖系统最常见的恶性肿瘤。尽管采用雄激素剥夺疗法等策略在一定程度上对治疗前列腺癌有效,但大多数患者最终会进展为临床尚无有效治疗手段的去势抵抗性前列腺癌。因此,寻找新的更加有效的前列腺癌治疗靶点就显得尤为关... 前列腺癌是男性生殖系统最常见的恶性肿瘤。尽管采用雄激素剥夺疗法等策略在一定程度上对治疗前列腺癌有效,但大多数患者最终会进展为临床尚无有效治疗手段的去势抵抗性前列腺癌。因此,寻找新的更加有效的前列腺癌治疗靶点就显得尤为关键。多项研究表明,微RNA(microRNAs,miRNAs)的异常表达与肿瘤的发生相关。已有报道显示,miRNA-485-5p(miR-485-5p)在多种肿瘤中发挥抑癌作用,但其在前列腺癌中的作用在较大程度上仍未可知。本研究旨在探究miR-485-5p在前列腺癌细胞增殖、迁移与侵袭的作用与机制。生物信息学预测和qRT-PCR检测发现,miR-485-5p在前列腺癌中表达下调。平板克隆形成实验、Transwell实验和划痕愈合实验证明,转染miR-485-5p模拟物显著抑制前列腺癌细胞的增殖、迁移与侵袭。生物信息学预测、双荧光素酶报告法、Western印迹和qRT-PCR检测证实,氧连接的N-乙酰氨基葡萄糖转移酶(O-linked N-acetylglucosamine transferase,OGT)是miR-485-5p的一个下游直接靶标。进一步的分析和检测显示,OGT在前列腺癌中呈高表达,转染OGT的siRNA能够显著抑制前列腺癌细胞的增殖、迁移与侵袭,同时有效逆转转染miR-485-5p抑制物所发挥的促癌作用。综上所述,miR-485-5p可以通过负向调控OGT进而抑制前列腺癌细胞的增殖、迁移与侵袭。本研究结果有助于进一步阐释miR-485-5p在前列腺癌中发生发展的作用和机制,可为寻找前列腺癌的治疗靶点提供实验依据。 展开更多
关键词 mir-485-5p 前列腺癌 氧连接的N-乙酰氨基葡萄糖转移酶 增殖 迁移
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