期刊文献+
共找到254,971篇文章
< 1 2 250 >
每页显示 20 50 100
Intelligent Operations: Global Public High-Power Charging Networks
1
作者 Anke Freitag Prashan De Silva 《Journal of Traffic and Transportation Engineering》 2025年第1期1-16,共16页
The global public HPC(high-power charging)network for EVs(electric vehicles)is rapidly expanding.This growth is crucial for supporting the increasing adoption of EVs but highlights the industry’s early stage.Regional... The global public HPC(high-power charging)network for EVs(electric vehicles)is rapidly expanding.This growth is crucial for supporting the increasing adoption of EVs but highlights the industry’s early stage.Regional maturity varies,with China leading due to strong government support,followed by Europe and the United States.A significant challenge is the lack of industry standards,causing inconsistencies in charger types and payment systems.Efforts are underway,to ensure interoperability and reliability.Interoperability is crucial for the success of EV HPC infrastructure,ensuring seamless integration among charge points,management systems,and service providers.Despite the use of protocols like the OCPP(Open Charge Point Protocol),variations in implementation create complexities.Ensuring uniform standards across the ecosystem is essential for reliability and efficiency.Vendor-specific error codes,which are more detailed than standardized codes,are vital for diagnosing issues but lack standardization,adding complexity.Addressing these challenges is key to supporting widespread EV adoption and enhancing user experience.To provide a compelling driver value proposition,EV charging services must be reliable and seamless.The operations and maintenance of the HPC network must be cost-effective and leverage the intelligence of the integrated ecosystem.The technical complexity of managing high-power DC charging,combined with diverse authentication and payment systems,results in numerous potential issues.Moving from reactive to predictive maintenance is essential for undisrupted operations and a smooth driver experience.Shell’s Intelligent Operations Technology Strategy incorporates GenAI elements in its advanced analytics and operational performance management tools.By ingesting big data from multiple sources across the EV ecosystem,Shell engineers can perform detailed pattern recognition and targeted troubleshooting.Monitoring,configurable alerting,and remote fixing based on auto-healing and targeted auto-allocation enhance charger availability and reduce downtime.This automation has evolved Shell’s maintenance and operations strategy from reactive to predictive,improving overall charger performance and user satisfaction.Key achievements include transitioning to prescriptive and preventive asset management approaches,significantly improving uptime and charging experience,and increasing commercial value through cost reduction and enhanced revenue.Future challenges include evolving OCPP,integrating data from non-OCPP systems,and ensuring interoperability across diverse systems.Standardization and cross-collaboration within the industry are essential for smooth interoperability,higher uptime,and increased CSR(charging success rate).Technological innovations will further shape the industry,promoting stabilization and efficiency as it matures. 展开更多
关键词 e-Mobility charging ecosystem intelligent operations predictive maintenance GenAI
在线阅读 下载PDF
Recognition of carrier-based aircraft flight deck operations based on dynamic graph
2
作者 Xingyu GUO Jiaxin LI +3 位作者 Hua WANG Junnan LIU Yafei LI Mingliang XU 《Chinese Journal of Aeronautics》 2025年第3期474-490,共17页
Accurate recognition of flight deck operations for carrier-based aircraft, based on operation trajectories, is critical for optimizing carrier-based aircraft performance. This recognition involves understanding short-... Accurate recognition of flight deck operations for carrier-based aircraft, based on operation trajectories, is critical for optimizing carrier-based aircraft performance. This recognition involves understanding short-term and long-term spatial collaborative relationships among support agents and positions from long spatial–temporal trajectories. While the existing methods excel at recognizing collaborative behaviors from short trajectories, they often struggle with long spatial–temporal trajectories. To address this challenge, this paper introduces a dynamic graph method to enhance flight deck operation recognition. First, spatial–temporal collaborative relationships are modeled as a dynamic graph. Second, a discretized and compressed method is proposed to assign values to the states of this dynamic graph. To extract features that represent diverse collaborative relationships among agents and account for the duration of these relationships, a biased random walk is then conducted. Subsequently, the Swin Transformer is employed to comprehend spatial–temporal collaborative relationships, and a fully connected layer is applied to deck operation recognition. Finally, to address the scarcity of real datasets, a simulation pipeline is introduced to generate deck operations in virtual flight deck scenarios. Experimental results on the simulation dataset demonstrate the superior performance of the proposed method. 展开更多
关键词 Carrier-based aircraft Flight deck operation Operation recognition Long spatial-temporal trajectories Dynamic graph Biased random walk Graph embeddings
原文传递
Multi-layer controlled remote implementation of partially unknown single-qudit operations
3
作者 Siyi Li Songya Ma Si Jin 《Communications in Theoretical Physics》 2025年第2期52-63,共12页
Our concern is to investigate controlled remote implementation of partially unknown operations with multiple layers.We first propose a scheme to realize the remote implementation of singlequbit operations belonging to... Our concern is to investigate controlled remote implementation of partially unknown operations with multiple layers.We first propose a scheme to realize the remote implementation of singlequbit operations belonging to the restricted sets.Then,the proposed scheme is extended to the case of single-qudit operations.As long as the controller and the higher-layer senders consent,the receiver can restore the desired state remotely operated by the sender.It is worth mentioning that the recovery operation is deduced by general formulas which clearly reveal the relationship with the measurement outcomes.For the sake of clarity,two specific examples with two levels are given respectively.In addition,we discuss the influence of amplitude-damping noise and utilize weak measurement and measurement reversal to effectively resist noise. 展开更多
关键词 controlled remote implementation of quantum operation multiple layers recovery operation amplitude-damping noise weak measurement and measurement reversal
原文传递
A Generalized Satellite Digital Twin System for Satellite Operations
4
作者 LIN Jiawei ZHANG Yujie +1 位作者 WU Xiaoming LIU Jianhua 《Aerospace China》 2025年第1期14-23,共10页
Digital twin shows broad application prospects in the aerospace field.This paper introduces a generalized satellite digital twin system in detail.With the innovative design concepts of modularization,generalization an... Digital twin shows broad application prospects in the aerospace field.This paper introduces a generalized satellite digital twin system in detail.With the innovative design concepts of modularization,generalization and modeling,on the one hand,the system has successfully achieved the reuse of software modules among different satellite models;on the other hand,it has achieved the reuse of software modules between the digital twin and the testing system,significantly improving the development efficiency of the digital twin system.The paper elaborates on the technical architecture and application fields of this digital twin system,and further prospects its future development.At the same time,through a real inorbit case,the engineering value of the digital twin system is strongly demonstrated. 展开更多
关键词 satellite operation GENERALIZATION digital twin
在线阅读 下载PDF
无人机作业参数对雾滴在桃树冠层沉积分布的影响
5
作者 蒋三生 卜小东 +1 位作者 郭辉 蒋晓 《中国农机化学报》 北大核心 2026年第1期147-152,共6页
为优选出无人机针对桃树喷施作业的参数组合,以双旋翼农业无人机为作业平台,设置三因素三水平的正交试验,通过试验结果和极差分析研究作业高度、作业速度、喷施流量对雾滴沉积密度、均匀性和穿透性的影响规律和影响程度。结果表明:作业... 为优选出无人机针对桃树喷施作业的参数组合,以双旋翼农业无人机为作业平台,设置三因素三水平的正交试验,通过试验结果和极差分析研究作业高度、作业速度、喷施流量对雾滴沉积密度、均匀性和穿透性的影响规律和影响程度。结果表明:作业高度H为3.5 m、作业速度V为2.5 m/s、喷施流量T为72 L/hm^(2)时,雾滴的沉积密度最佳,平均为34.03个/cm^(2),同时具有较好的沉积均匀性和穿透性;桃树上层沉积密度的较优因素水平:H=3.5 m、V=2.5 m/s、T=108 L/hm^(2),沉积分布均匀性的较优因素水平:H=4.0 m、V=2.0 m/s、T=72 L/hm^(2);桃树中、下层沉积密度的较优因素水平:H=4.0 m、V=2.5 m/s、T=72 L/hm^(2),中层沉积分布均匀性的较优因素水平:H=4.0 m、V=1.5 m/s、T=72 L/hm^(2),下层沉积分布均匀性的较优因素水平:H=3.5 m、V=2.5 m/s、T=90 L/hm^(2);雾滴沉积穿透性的较优因素水平:H=3.5 m、V=2.0 m/s、T=108 L/hm^(2);影响雾滴沉积效果的主次顺序在树冠上、中、下3个高度层均呈现不同的结果。综合对比发现,作业高度对喷施雾滴的沉积密度和沉积均匀性影响最大,作业速度次之,喷施流量的影响最小;影响雾滴沉积密度穿透性大小的因素主次顺序为喷施流量、作业高度、作业速度。试验结果可为农业无人机在果树产业中的绿色飞防应用和发展提供理论依据。 展开更多
关键词 无人机 作业参数 雾滴 沉积分布 桃树
在线阅读 下载PDF
基于DEA模型的多院区发展模式下某公立三级综合医院临床科室运行效率研究
6
作者 王倩 张崔建 +3 位作者 于楠 魏玉梅 李娜 姜辉 《中国医院》 北大核心 2026年第1期49-52,共4页
目的:在“一院多区”发展模式下,量化评估综合医院临床科室运行效率,识别资源配置问题,为促进公立医院高质量发展提供参考。方法:选取多院区发展模式下某公立三级综合医院的33个临床科室为研究对象,采用DEA-BCC模型对2024年各科室运行... 目的:在“一院多区”发展模式下,量化评估综合医院临床科室运行效率,识别资源配置问题,为促进公立医院高质量发展提供参考。方法:选取多院区发展模式下某公立三级综合医院的33个临床科室为研究对象,采用DEA-BCC模型对2024年各科室运行效率进行静态分析,并结合投影分析识别投入冗余与产出不足。结果:2024年医院各临床科室的综合效率、纯技术效率和规模效率均值分别为0.720、0.906、0.783,其中11个科室(33.33%)达到DEA有效,4个科室(12.12%)处于弱有效状态,非有效科室占比超过50%,且多数由于规模效率偏低导致。结论:医院临床科室运行效率呈现多维度特征,而规模效率是影响综合效率的主要因素;可通过创新资源配置模式、建立动态监测机制、构建数据驱动的精准质控体系、实施学科差异化发展策略等举措,促进医院综合效能提升,助力公立医院实现多院区高质量协同发展。 展开更多
关键词 公立医院 多院区 临床科室 运行效率 数据包络分析
暂未订购
混沌映射与改进CNOT操作的图像加密算法
7
作者 张磊 蒲冰倩 +2 位作者 姜鸽 刘毓涛 常亮 《计算机应用研究》 北大核心 2026年第1期247-255,共9页
针对传统图像加密算法在对抗已知明文攻击和唯密文攻击方面的不足,提出一种结合混沌映射与改进CNOT操作的图像加密方法(image encryption algorithm integrating chaotic mapping and enhanced CNOT operations,IEA-CECO)。通过提取图... 针对传统图像加密算法在对抗已知明文攻击和唯密文攻击方面的不足,提出一种结合混沌映射与改进CNOT操作的图像加密方法(image encryption algorithm integrating chaotic mapping and enhanced CNOT operations,IEA-CECO)。通过提取图像哈希值动态生成混沌参数,实现“一图一钥”的密钥绑定;采用改进的CNOT操作,结合条件翻转最高位和级联扩散机制,增强非线性混淆能力。实验结果表明,该算法密钥敏感性达50%,加密图像直方图标准差降至8.7,相邻像素相关系数趋近于0,信息熵提升至7.9567,同时加密效率满足实时性需求。IEA-CECO有效解决了密钥静态性和统计残留问题,适用于高安全性实时图像加密场景。 展开更多
关键词 图像加密 混沌映射 动态密钥 CNOT操作 实时加密
在线阅读 下载PDF
基于多特征融合的集装箱船导轨缺陷检测算法
8
作者 李瑞 张贤宇 +2 位作者 尤尹 汪骥 张全有 《大连理工大学学报》 北大核心 2026年第1期86-93,共8页
针对传统集装箱船导轨缺陷检测方法完全依赖人工目视检查,存在效率低、工作量大等问题,提出一种基于多特征融合的集装箱船导轨缺陷检测算法.设计了数据自适应重采样处理方法,降低缺陷种类分布不均的影响.在骨干网络设置多梯度感受野聚... 针对传统集装箱船导轨缺陷检测方法完全依赖人工目视检查,存在效率低、工作量大等问题,提出一种基于多特征融合的集装箱船导轨缺陷检测算法.设计了数据自适应重采样处理方法,降低缺陷种类分布不均的影响.在骨干网络设置多梯度感受野聚合模块,聚合导轨不同程度破损特征和周围环境特征.根据上述方法,在残差分析模块后嵌入混合注意力机制,有效引导多尺度特征流关注重点特征信息.在网络的特征拼接处融合特征重组上采样算子,扩张流入特征的局部感受野,有效整合全局细微特征信息.在测试集上的验证以及与人工效率的比对表明:所提改进算法对导轨缺陷检测的均值平均精度可达到97.0%,相较原YOLOv5算法提升2.9个百分点,有效提升了集装箱船导轨缺陷检测精度. 展开更多
关键词 船舶建造工艺 集装箱船导轨缺陷 混合注意力机制 特征重组上采样算子
在线阅读 下载PDF
基于智能APP的路径化护理模式在肺癌手术患者加速康复中的应用效果
9
作者 范光伟 田洁 +5 位作者 李娜 刘青春 张伟 李华 闫君 王蓉 《临床医学研究与实践》 2026年第1期151-154,189,共5页
目的探讨基于智能APP的路径化护理模式在肺癌手术患者加速康复中的应用效果。方法选取2022年1月至2023年6月胸外科加速康复外科(ERAS)病房行胸腔镜下肺癌根治手术的295例患者,将2022年1月至9月的145例患者纳入对照组(实施传统护理模式);... 目的探讨基于智能APP的路径化护理模式在肺癌手术患者加速康复中的应用效果。方法选取2022年1月至2023年6月胸外科加速康复外科(ERAS)病房行胸腔镜下肺癌根治手术的295例患者,将2022年1月至9月的145例患者纳入对照组(实施传统护理模式);2022年10月至2023年6月的150例患者纳入观察组(采取基于智能APP的路径化护理模式)。比较两组的康复指标、并发症发生情况、焦虑和抑郁情况、护理满意度、健康知识知晓情况。结果观察组的康复指标、并发症总发生率、护理满意度优于对照组(P<0.05)。观察组干预后的焦虑及抑郁评分均低于对照组(P<0.05)。观察组干预后的健康知识知晓评分高于对照组(P<0.001)。结论基于智能APP的路径化护理模式有利于降低肺癌手术患者的并发症发生率,改善心理状况,提升对护士工作的满意度,从而促进加速康复,值得在临床推广。 展开更多
关键词 智能APP 路径化护理 肺癌根治术 加速康复外科
暂未订购
Mixed Quasi-martingale Hardy Spaces
10
作者 ZHANG Chuanzhou LI Shimeng HE Zhibin 《应用数学》 北大核心 2026年第1期221-231,共11页
In this article,we conduct a study on mixed quasi-martingale Hardy spaces that are defined by means of the mixed L_(p)-norm.By utilizing Doob’s inequalities,we explore the atomic decomposition and quasi-martingale in... In this article,we conduct a study on mixed quasi-martingale Hardy spaces that are defined by means of the mixed L_(p)-norm.By utilizing Doob’s inequalities,we explore the atomic decomposition and quasi-martingale inequalities of mixed quasi-martingale Hardy spaces.Moreover,we furnish sufficient conditions for the boundedness ofσ-sublinear operators in these spaces.These findings extend the existing conclusions regarding mixed quasi-martingale Hardy spaces defined with the help of the mixed L_(p)-norm. 展开更多
关键词 Mixed quasi-martingale Hardy space Atomic Decomposition σ-sublinear operator
在线阅读 下载PDF
耐心资本赋能企业全要素生产率提升的机制和途径
11
作者 胡海峰 张烨 王爱萍 《新疆师范大学学报(哲学社会科学版)》 北大核心 2026年第1期62-73,F0002,共13页
耐心资本秉持超越短期利益、专注长期价值积累的理念,具有战略性、稳定性与风险容忍性特征,对企业全要素生产率的提升发挥重要作用。文本以2013-2024年我国A股上市公司为研究样本,重点探讨耐心资本对企业全要素生产率的影响效应及作用... 耐心资本秉持超越短期利益、专注长期价值积累的理念,具有战略性、稳定性与风险容忍性特征,对企业全要素生产率的提升发挥重要作用。文本以2013-2024年我国A股上市公司为研究样本,重点探讨耐心资本对企业全要素生产率的影响效应及作用机制。研究结果表明,耐心资本投入对企业全要素生产率具有显著的提升作用。通过作用机制检验发现,耐心资本主要通过强化企业可持续经营导向、稳定供应链合作关系以及推动新质化发展三条路径促进全要素生产率提升;异质性检验显示,耐心资本的积极效应在高金融发展水平、低政府补助地区以及高科技企业与融资约束较高的企业中更加突出。此外,提高信息披露质量能够增强耐心资本对企业的认同,引导更多长期资本流向具有发展潜力的企业。 展开更多
关键词 耐心资本 全要素生产率 可持续经营 供应链关系 新质生产力
原文传递
事理学视角下高空作业安全带系挂检测器设计
12
作者 李明泽 孟庆军 《工业设计》 2026年第1期138-141,共4页
高空作业中因安全带系挂不到位引发的安全事故频发,现有检测设备存在场景适配性不足、人机交互设计不完善等问题。为提升高空作业安全防控水平,文章基于设计事理学理论,系统分析了高空作业应用场景中外部因素(作业环境、流程规范、设备... 高空作业中因安全带系挂不到位引发的安全事故频发,现有检测设备存在场景适配性不足、人机交互设计不完善等问题。为提升高空作业安全防控水平,文章基于设计事理学理论,系统分析了高空作业应用场景中外部因素(作业环境、流程规范、设备性能)与内部因素(人员行为、操作逻辑)对坠落风险的影响。通过分析高空作业安全防控的功能需求,导出检测设备的设计优化方向,以帮助作业人员规避潜在风险。在此基础上,提出了安全带系挂检测器的设计方案,通过优化检测方式、使用便捷性和抗干扰性等设计要素,提升设备与高空作业监护场景的适配性,为高空作业安全防护设备的创新设计提供理论依据与实践参考。 展开更多
关键词 系挂检测器 动量检测 设计事理学 安全带 高空作业 安全监护
在线阅读 下载PDF
基于多目标优化的复杂热电联产系统运行规划
13
作者 陈坚红 王国雲 +2 位作者 左克清 张洪坤 鲍彦克 《浙江大学学报(工学版)》 北大核心 2026年第1期148-157,共10页
热电厂的扩建、改造和升级显著增加了热电联产系统在机组数量、种类及性能劣化程度等方面的复杂性.针对复杂热电联产系统的运行规划,综合考虑机组在实际运行过程中的启停状态、爬坡速率等影响因素,构建基于能效、㶲、经济、环境等的多目... 热电厂的扩建、改造和升级显著增加了热电联产系统在机组数量、种类及性能劣化程度等方面的复杂性.针对复杂热电联产系统的运行规划,综合考虑机组在实际运行过程中的启停状态、爬坡速率等影响因素,构建基于能效、㶲、经济、环境等的多目标优化模型.引入熵权法客观地分配各目标的权重,将多目标优化问题转化为单目标优化问题;采用动态规划算法进行求解,确保最优解的确定性和客观性.以某热电厂的复杂热电联产系统为例,随机选取24 h的热电负荷需求进行运行规划和计算分析,并将优化结果与原设计方案进行对比,结果表明优化计算后运行成本降低了7.96万元/d.所提模型能够有效地提升复杂热电联产系统运行的经济性与可靠性. 展开更多
关键词 复杂热电联产系统 多目标优化 运行规划 熵权法 动态规划法
在线阅读 下载PDF
Automated Pipe Defect Identification in Underwater Robot Imagery with Deep Learning
14
作者 Mansour Taheri Andani Farhad Ameri 《哈尔滨工程大学学报(英文版)》 2026年第1期197-215,共19页
Underwater pipeline inspection plays a vital role in the proactive maintenance and management of critical marine infrastructure and subaquatic systems.However,the inspection of underwater pipelines presents a challeng... Underwater pipeline inspection plays a vital role in the proactive maintenance and management of critical marine infrastructure and subaquatic systems.However,the inspection of underwater pipelines presents a challenge due to factors such as light scattering,absorption,restricted visibility,and ambient noise.The advancement of deep learning has introduced powerful techniques for processing large amounts of unstructured and imperfect data collected from underwater environments.This study evaluated the efficacy of the You Only Look Once(YOLO)algorithm,a real-time object detection and localization model based on convolutional neural networks,in identifying and classifying various types of pipeline defects in underwater settings.YOLOv8,the latest evolution in the YOLO family,integrates advanced capabilities,such as anchor-free detection,a cross-stage partial network backbone for efficient feature extraction,and a feature pyramid network+path aggregation network neck for robust multi-scale object detection,which make it particularly well-suited for complex underwater environments.Due to the lack of suitable open-access datasets for underwater pipeline defects,a custom dataset was captured using a remotely operated vehicle in a controlled environment.This application has the following assets available for use.Extensive experimentation demonstrated that YOLOv8 X-Large consistently outperformed other models in terms of pipe defect detection and classification and achieved a strong balance between precision and recall in identifying pipeline cracks,rust,corners,defective welds,flanges,tapes,and holes.This research establishes the baseline performance of YOLOv8 for underwater defect detection and showcases its potential to enhance the reliability and efficiency of pipeline inspection tasks in challenging underwater environments. 展开更多
关键词 YOLO8 Underwater robot Object detection Underwater pipelines Remotely operated vehicle Deep learning
在线阅读 下载PDF
含p-Laplacian算子的非线性分数阶q-差分方程的无界解
15
作者 王菊芳 张艺琼 禹长龙 《河北师范大学学报(自然科学版)》 2026年第1期1-8,共8页
聚焦无穷区间上含p-Laplacian算子的分数阶q-差分方程可解性的研究.首先,计算对应线性方程的Green函数,并深入剖析其性质.其次,构建积分算子T,并运用Leray-Schauder非线性更替定理和Banach压缩映像原理,获得了该问题无界解的存在性和唯... 聚焦无穷区间上含p-Laplacian算子的分数阶q-差分方程可解性的研究.首先,计算对应线性方程的Green函数,并深入剖析其性质.其次,构建积分算子T,并运用Leray-Schauder非线性更替定理和Banach压缩映像原理,获得了该问题无界解的存在性和唯一性定理.最后,通过实例验证所得定理的有效性.研究结果不仅拓展了分数阶q-差分方程非局部问题的可解性理论,更为其在相关领域的实际应用提供理论指导. 展开更多
关键词 多点边值问题 分数阶q-微积分 P-LAPLACIAN算子 Leray-Schauder非线性更替定理 无穷区间
在线阅读 下载PDF
Breast cancer stem cell activity driven by ME18D gene expression in the tumor microenvironment
16
作者 De-Yang Guo Zhang-Yi Liu Qian-Chuan Yi 《World Journal of Stem Cells》 2026年第1期49-65,共17页
BACKGROUND Breast cancer is one of the most prevalent malignancies affecting women worldwide,with approximately 2.3 million new cases diagnosed annually.Breast cancer stem cells(BCSCs)play pivotal roles in tumor initi... BACKGROUND Breast cancer is one of the most prevalent malignancies affecting women worldwide,with approximately 2.3 million new cases diagnosed annually.Breast cancer stem cells(BCSCs)play pivotal roles in tumor initiation,progression,metastasis,therapeutic resistance,and disease recurrence.Cancer stem cells possess selfrenewal capacity,multipotent differentiation potential,and enhanced tumorigenic activity,but their molecular characteristics and regulatory mechanisms require further investigation.AIM To comprehensively characterize the molecular features of BCSCs through multiomics approaches,construct a prognostic prediction model based on stem cellrelated genes,reveal cell-cell communication networks within the tumor microenvironment,and provide theoretical foundation for personalized treatment strategies.METHODS Flow cytometry was employed to detect the expression of BCSC surface markers(CD34,CD45,CD29,CD90,CD105).Transcriptomic analysis was performed to identify differentially expressed genes.Least absolute shrinkage and selection operator regression analysis was utilized to screen key prognostic genes and construct a risk scoring model.Single-cell RNA sequencing and spatial transcriptomics were applied to analyze tumor heterogeneity and spatial gene expression patterns.Cell-cell communication network analysis was conducted to reveal interactions between stem cells and the microenvironment.RESULTS Flow cytometric analysis revealed the highest expression of CD105(96.30%),followed by CD90(68.43%)and CD34(62.64%),while CD29 showed lower expression(7.16%)and CD45 exhibited the lowest expression(1.19%).Transcriptomic analysis identified 3837 significantly differentially expressed genes(1478 upregulated and 2359 downregulated).Least absolute shrinkage and selection operator regression analysis selected 10 key prognostic genes,and the constructed risk scoring model effectively distinguished between high-risk and low-risk patient groups(P<0.001).Single-cell analysis revealed tumor cellular heterogeneity,and spatial transcriptomics demonstrated distinct spatial expression gradients of stem cell-related genes.MED18 gene showed significantly higher expression in malignant tissues(P<0.001)and occupied a central position in cell-cell communication networks,exhibiting significant correlations with tumor cells,macrophages,fibroblasts,and endothelial cells.CONCLUSION This study comprehensively characterized the molecular features of BCSCs through multi-omics approaches,identified reliable surface markers and key regulatory genes,and constructed a prognostic prediction model with clinical application value. 展开更多
关键词 Breast cancer stem cells Surface markers TRANSCRIPTOMICS Least absolute shrinkage and selection operator regression Prognostic model
暂未订购
Simulation of Police Actions and Operations
17
作者 Grzegorz Gudzbeler Andrzej Urban Mariusz Nepelski 《Journal of Physical Science and Application》 2012年第4期103-110,共8页
The paper presents modern perception of crisis management and its importance for security in the context of non-military threats. It shows the role of the police as a part of a governmental system, performing their ta... The paper presents modern perception of crisis management and its importance for security in the context of non-military threats. It shows the role of the police as a part of a governmental system, performing their tasks in all stages of crisis management. And it is about simulator crisis situation. 展开更多
关键词 MODELING SIMULATION human behaviors commanding police operations.
在线阅读 下载PDF
A radiomics approach for predicting gait freezing in Parkinson's disease based on resting-state functional magnetic resonance imaging indices:A cross-sectional study
18
作者 Miaoran Guo Hu Liu +6 位作者 Long Gao Hongmei Yu Yan Ren Yingmei Li Huaguang Yang Chenghao Cao Guoguang Fan 《Neural Regeneration Research》 2026年第4期1621-1627,共7页
Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indice... Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indices,has provided a fresh perspective and valuable insight into the study of freezing of gait in Parkinson's disease.It has been revealed that Parkinson's disease is accompanied by widespread irregularities in inherent brain network activity.However,the effective integration of the multi-level indices of resting-state functional magnetic resonance imaging into clinical settings for the diagnosis of freezing of gait in Parkinson's disease remains a challenge.Although previous studies have demonstrated that radiomics can extract optimal features as biomarkers to identify or predict diseases,a knowledge gap still exists in the field of freezing of gait in Parkinson's disease.This cross-sectional study aimed to evaluate the ability of radiomics features based on multi-level indices of resting-state functional magnetic resonance imaging,along with clinical features,to distinguish between Parkinson's disease patients with and without freezing of gait.We recruited 28 patients with Parkinson's disease who had freezing of gait(15 men and 13 women,average age 63 years)and 30 patients with Parkinson's disease who had no freezing of gait(16 men and 14 women,average age 64 years).Magnetic resonance imaging scans were obtained using a 3.0T scanner to extract the mean amplitude of low-frequency fluctuations,mean regional homogeneity,and degree centrality.Neurological and clinical characteristics were also evaluated.We used the least absolute shrinkage and selection operator algorithm to extract features and established feedforward neural network models based solely on resting-state functional magnetic resonance imaging indicators.We then performed predictive analysis of three distinct groups based on resting-state functional magnetic resonance imaging indicators indicators combined with clinical features.Subsequently,we conducted 100 additional five-fold cross-validations to determine the most effective model for each classification task and evaluated the performance of the model using the area under the receiver operating characteristic curve.The results showed that when differentiating patients with Parkinson's disease who had freezing of gait from those who did not have freezing of gait,or from healthy controls,the models using only the mean regional homogeneity values achieved the highest area under the receiver operating characteristic curve values of 0.750(with an accuracy of 70.9%)and 0.759(with an accuracy of 65.3%),respectively.When classifying patients with Parkinson's disease who had freezing of gait from those who had no freezing of gait,the model using the mean amplitude of low-frequency fluctuation values combined with two clinical features achieved the highest area under the receiver operating characteristic curve of 0.847(with an accuracy of 74.3%).The most significant features for patients with Parkinson's disease who had freezing of gait were amplitude of low-frequency fluctuation alterations in the left parahippocampal gyrus and two clinical characteristics:Montreal Cognitive Assessment and Hamilton Depression Scale scores.Our findings suggest that radiomics features derived from resting-state functional magnetic resonance imaging indices and clinical information can serve as valuable indices for the identification of freezing of gait in Parkinson's disease. 展开更多
关键词 amplitude of low-frequency fluctuation degree centrality feedforward neural network freezing of gait machine learning parahippocampal gyrus Parkinson's disease receiver operating characteristic regional homogeneity resting-state functional magnetic resonance imaging
暂未订购
双深度四向穿梭车仓储系统复合作业任务分配研究
19
作者 武照云 何学武 +3 位作者 申发生 李丽 张业豪 张中伟 《包装工程》 北大核心 2026年第1期132-142,共11页
目的提高双深度四向穿梭车仓储系统出入库作业效率,降低设备的空载率。方法针对多设备的加减速特性、并行作业的特性,以及出库作业中可能触发倒箱作业的概率性场景,以最小化出入库任务分配方案的总完工时间为优化目标,剖析多个四向穿梭... 目的提高双深度四向穿梭车仓储系统出入库作业效率,降低设备的空载率。方法针对多设备的加减速特性、并行作业的特性,以及出库作业中可能触发倒箱作业的概率性场景,以最小化出入库任务分配方案的总完工时间为优化目标,剖析多个四向穿梭车和多个提升机的复合作业流程,构建相应的数学模型,并提出一种多策略改进哈里斯鹰优化算法来求解该模型,利用离散事件仿真来记录各穿梭车作业总完工时间,通过Python进行过程仿真分析,来获取最优任务分配方案和最短总完工时间。结果选取3种不同规模的任务算例,将文中所提的多策略改进哈里斯鹰优化算法,与标准哈里斯鹰优化算法、遗传算法、粒子群算法的求解表现进行对比。结果表明,在不同规模任务案例中改进算法的求解质量均最优。结论文中提出的复合作业任务分配方法能够有效提升双深度四向穿梭车仓储系统的作业效率。 展开更多
关键词 双深度四向穿梭车仓储系统 复合作业 任务分配 离散事件仿真 哈里斯鹰优化算法
在线阅读 下载PDF
二氧化钛改性炭黑催化剂电合成H_(2)O_(2)反应器设计与性能优化
20
作者 李皓瑜 王凯旋 +2 位作者 张候瑞 陈硕 全燮 《大连理工大学学报》 北大核心 2026年第1期40-47,共8页
通过二电子氧还原反应(2e^(-)ORR)直接电合成过氧化氢(H_(2)O_(2))为能源密集型蒽醌氧化工艺提供了一种可行的替代方案.然而,从实验规模转变到工业规模电合成H_(2)O_(2)的过程中,一个主要的障碍是开发大电极面积的反应器.因此,以二氧化... 通过二电子氧还原反应(2e^(-)ORR)直接电合成过氧化氢(H_(2)O_(2))为能源密集型蒽醌氧化工艺提供了一种可行的替代方案.然而,从实验规模转变到工业规模电合成H_(2)O_(2)的过程中,一个主要的障碍是开发大电极面积的反应器.因此,以二氧化钛改性炭黑为阴极催化剂,设计了81 cm^(2)阴极的H池反应器和气体扩散反应器,并构建了电合成H_(2)O_(2)的反应系统.由于氧传质和产热无法有效排出,H池反应器难以在50 mA/cm^(2)以上电流密度下高效率运行,相比之下,气体扩散反应器可以在100 mA/cm^(2)下实现525.8 mmol/(L·h)的高H_(2)O_(2)产率,且法拉第效率达到84%.通过调节电流密度和阴极液流速等运行参数,该气体扩散反应器电合成H_(2)O_(2)的最低电解质和电能总成本为5.149元/kg.该工作为设计低成本的分散式H_(2)O_(2)生产系统提供了可行的策略. 展开更多
关键词 电合成 反应器设计 气体扩散电极 运行参数优化
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部