期刊文献+
共找到36,215篇文章
< 1 2 250 >
每页显示 20 50 100
An integrated split and dummy gates MOSFET with fast turn-off and reverse recovery characteristics
1
作者 陈伟中 牟柳亭 +2 位作者 秦海峰 张红升 韩郑生 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期545-550,共6页
A power MOSFET with integrated split gate and dummy gate(SD-MOS) is proposed and demonstrated by the TCAD SENTAURUS.The split gate is surrounded by the source and shielded by the dummy gate.Consequently,the coupling a... A power MOSFET with integrated split gate and dummy gate(SD-MOS) is proposed and demonstrated by the TCAD SENTAURUS.The split gate is surrounded by the source and shielded by the dummy gate.Consequently,the coupling area between the split gate and the drain electrode is reduced,thus the gate-to-drain charge(Q_(GD)),reverse transfer capacitance(C_(RSS)) and turn-off loss(E_(off)) are significantly decreased.Moreover,the MOS-channel diode is controlled by the dummy gate with ultra-thin gate oxide t_(ox),which can be turned on before the parasitic P-base/N-drift diode at the reverse conduction,then the majority carriers are injected to the N-drift to attenuate the minority injection.Therefore,the reverse recovery charge(Q_(RR)),time(T_(RR)) and peak current(I_(RRM)) are effectively reduced at the reverse freewheeling state.Additionally,the specific on-resistance(R_(on,sp)) and breakdown voltage(BV) are also studied to evaluate the static properties of the proposed SD-MOS.The simulation results show that the Q_(GD) of 6 nC/cm^(2),the C_(RSS) of 1.1 pF/cm^(2) at the V_(DS) of 150 V,the QRR of 1.2 μC/cm^(2) and the R_(on,sp) of 8.4 mΩ·cm^(2) are obtained,thus the figures of merit(FOM) including Q_(GD) ×R_(on,sp) of50 nC·mΩ,E_(off) × R_(on,sp) of 0.59 mJ·mΩ and the Q_(RR) × R_(on,sp) of 10.1 μC·mΩ are achieved for the proposed SD-MOS. 展开更多
关键词 MOSFET split gate dummy gate turn-off and reverse recovery
下载PDF
基于灰度均值的自适应FAST角点检测优化算法
2
作者 刘艳 李一桐 《电光与控制》 CSCD 北大核心 2024年第2期65-71,91,共8页
光照不均、突变引起的灰度变化会影响图像特征检测效果。为此,设计一种基于灰度均值的自适应FAST-9-12角点检测算法。首先,利用特征点的延展性设计一种小面积双重检测模板,减少像素点与中心点的比较次数,提高区域正检率和检测速度;其次... 光照不均、突变引起的灰度变化会影响图像特征检测效果。为此,设计一种基于灰度均值的自适应FAST-9-12角点检测算法。首先,利用特征点的延展性设计一种小面积双重检测模板,减少像素点与中心点的比较次数,提高区域正检率和检测速度;其次,依据图像局部灰度均值,在每个像素点检测模板内自适应调整阈值,避免灰度变化影响检测效果;最后,根据柔性非极大值抑制的思想设计角点半径抑制原则,筛选鲁棒性更强的角点。在Inria遥感影像数据集上的实验结果表明,FAST-9-12角点检测速度比FAST-12-16,FAST-9-16两种模板提高22%左右,因自适应阈值的提取方式不易受光照影响,检测准确率分别提高4.16和3.11个百分点,实现了图像特征快速和精准检测。 展开更多
关键词 fast角点检测 双重模板 自适应阈值 柔性非极大值抑制 角点半径抑制
下载PDF
基于FAST和Sobol指数法的雷达系统效能敏感性分析
3
作者 胡涛 申立群 +2 位作者 朱镜达 孙成会 董伟锋 《系统工程与电子技术》 EI CSCD 北大核心 2024年第2期561-569,共9页
为了以较小的代价快速提升对空探测雷达系统的综合效能,首先搭建了对空探测雷达系统综合效能的评估指标体系,在此基础上完成了综合效能评估模型的建立。选择两种基于方差原理的全局敏感性分析方法,即傅里叶幅度敏感性测试(Fourier ampli... 为了以较小的代价快速提升对空探测雷达系统的综合效能,首先搭建了对空探测雷达系统综合效能的评估指标体系,在此基础上完成了综合效能评估模型的建立。选择两种基于方差原理的全局敏感性分析方法,即傅里叶幅度敏感性测试(Fourier amplitudes sensitivity test,FAST)和Sobol指数法,分别从频域和时域对建立的评估模型进行敏感性分析。在基于FAST进行敏感性分析时,提出了21维输入指标所对应的特征频率集的选取方法;在基于Sobol指数法进行敏感性分析时,考虑了二阶及高阶敏感性指数的影响。对比FAST和Sobol指数法的分析结果,两种方法获得的敏感性分析结果具有较好的一致性。其中,功率和频率为对空探测雷达系统的主要影响指标,为雷达系统的研发和升级提供了可靠性依据。 展开更多
关键词 雷达系统 效能评估 敏感性分析 傅里叶幅度敏感性测试 Sobol指数法
下载PDF
混合光谱曲线的Fast ICA盲源解混及影响因子研究
4
作者 戴佳乐 汪金花 +2 位作者 李孟倩 韩秀丽 缪若梵 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第5期1312-1320,共9页
混合物高光谱分析是矿物无损检测的关键技术。文中将混合物350~2500 nm区间光谱反射率变化看作时域变化的一维序列信号,将混合物光谱分离转变为时域信号的盲源分离问题。为了分析混合光谱解混速度和准确度的影响因子,采用Fast ICA数学... 混合物高光谱分析是矿物无损检测的关键技术。文中将混合物350~2500 nm区间光谱反射率变化看作时域变化的一维序列信号,将混合物光谱分离转变为时域信号的盲源分离问题。为了分析混合光谱解混速度和准确度的影响因子,采用Fast ICA数学模型对混合物实测高光谱反射曲线进行了盲源解混试验,从解混过程的白化方式、初始权阵,源光谱高斯性3个方面分析了光谱解混的结果,为混合物光谱检测的后期分析提供了研究基础。选取化学纯氧化铜和氧化亚铜混合物、碱式碳酸铜和氢氧化铜混合物为试验对象,采用解混性能指数PI、光谱均方根误差和光谱角距离作为评价指标,开展了源光谱高斯性与g函数、ZCA和PCA白化方式、及单位权、随机权、指定权3种初始权对解混光谱结果影响的对比实验。实验结果表明:Fast ICA算法在未知混合矿物高光谱先验信息的基础上,能够有效分离出混合物组分源光谱,样本分离精度PI值均小于0.18,光谱盲源解混的效果显著。解混后光谱曲线与源光谱曲线在特征趋势上保持一致,具有相同的吸收位置和特征峰,但是存在一定尺度的差异。另外,源光谱的高斯性与解混g函数的选取会直接影响解混结果,亚高斯区间曲线分离精度优于超高斯部分。依据高斯性进行分段解混结果的吸收特征会更加突出,与源光谱反射率数值差异也随之增大;光谱预处理的白化方式会对解混结果精度产生微小影响,经过ZCA白化后解混结果的分离精度、光谱的准确度均略高于PCA白化;在Fast ICA模型3种初始权解混结果对比发现,以初次迭代结果计算的指定权进行迭代解混时,其分离精度、解混准确度及解混时间均为最佳,解混过程更易收敛。结果表明,根据全波段高斯性来选取g函数解混效果最优,分离指数PI小于0.14,光谱角距离在0.1左右,ZCA白化比PCA白化对解混光谱的影响更小,ZCA白化后的两组混合物解混的分离指数在0.1左右,而PCA白化的分离指数PI均高于0.13,当指定权作初始权时有助于提高牛顿迭代中收敛速度,使解混光谱更接近组分已知光谱,指定权的解混时间低于0.2 s,其他两种定权方式均在0.3 s以上。 展开更多
关键词 混合光谱解混 fast ICA盲源解混 高斯性 白化 初始权
下载PDF
基于Kano-FAST-E的鞋面压合机优化设计
5
作者 周红宇 张林涵 +2 位作者 刘津圻 姜雯馨 薛爽 《包装工程》 CAS 北大核心 2024年第8期308-317,共10页
目的降低鞋面压合机设备作业过程中的失误率、优化人机交互体验。方法基于Kano模型调研分析作业人员与企业经理对当前设备的使用感受及需求;利用FAST理论重新定义设备的功能区域并指导设计展开;基于人机工程学理论(E),对设计方案的功能... 目的降低鞋面压合机设备作业过程中的失误率、优化人机交互体验。方法基于Kano模型调研分析作业人员与企业经理对当前设备的使用感受及需求;利用FAST理论重新定义设备的功能区域并指导设计展开;基于人机工程学理论(E),对设计方案的功能布局和结构尺寸进行优化,提升人机操作效率;利用眼动试验对改进前后的功能布局进行对比分析验证,并借助李克特量表对设计方案进行用户满意度评价。结果完成鞋面压合机的优化设计实践,提升了设备的人机性能和用户满意度,有效提高了作业人员认读效率、减少视觉疲劳和错误操作。结论改进后的鞋面压合机赋予了工人更加安全、高效且人性化的操作模式,验证了Kano-FAST-E的设计策略对该设备的人机优化设计具有指导意义,也为同类设备的开发实践提供参考。 展开更多
关键词 鞋面压合机 KANO模型 fast理论 人机工程 眼动试验
下载PDF
基于改进FAST的电力工程图纸识别与校核技术
6
作者 张华 肖莹 孙海森 《电子设计工程》 2024年第10期186-190,共5页
针对人工评审电力施工图预算工程量过程中存在的耗时费力及准确性较低等问题,设计了一种基于改进FAST算法与VGG网络的工程图纸识别与数据校核模型。该模型针对传统FAST算法误判率高、抗噪声性能差等不足,提出了基于积分核的改进FAST算法... 针对人工评审电力施工图预算工程量过程中存在的耗时费力及准确性较低等问题,设计了一种基于改进FAST算法与VGG网络的工程图纸识别与数据校核模型。该模型针对传统FAST算法误判率高、抗噪声性能差等不足,提出了基于积分核的改进FAST算法,以降低角点检测误判率和检测时间。并采用VGG网络进行输入特征与图纸数据校核之间的关联分析,从而实现了电力工程图纸符号智能识别与电力工程量的智能校核。算例验证结果表明,所提IFAST-VGG算法对图纸识别与工程量校核的平均准确率分别为90.6%和91.6%,均高于其他对比算法,可以应用于实际工程中。 展开更多
关键词 角点检测 深度学习 辅助评审 fast算法 VGG网络
下载PDF
市民对脑卒中FAST法则认知度的初步调查——以廊坊市为例
7
作者 刘玉恒 张英杰 +1 位作者 张松 邹鹏辉 《黑龙江科学》 2024年第8期113-117,120,共6页
近年来脑血管发病逐渐年轻化,及时有效地判断卒中发生对于防治脑血管意外具有较好的效用。通过机构自拟以FAST法则为基础的调查问卷,采用线上、线下相结合方式进行调研,探究人们对FAST法则的了解及掌握程度。结果表明,廊坊市部分人的卒... 近年来脑血管发病逐渐年轻化,及时有效地判断卒中发生对于防治脑血管意外具有较好的效用。通过机构自拟以FAST法则为基础的调查问卷,采用线上、线下相结合方式进行调研,探究人们对FAST法则的了解及掌握程度。结果表明,廊坊市部分人的卒中知识掌握良好,但掌握不全面,相关内容繁杂不精简。小部分人对于卒中存在盲区,理解较为模糊,易导致疾病发生后产生不良后果,说明廊坊市部分城区卒中宣传成果良好,居民通过宣传、生活经验等熟悉卒中的发作情况与症状表现。部分机构及医疗卫生部门仍需加大宣传力度及科普程度,消灭盲区,增强人们对疾病的日常注意程度,学会自我防病。 展开更多
关键词 脑卒中 fast法则 认知度 廊坊
下载PDF
A review of salivary composition changes induced by fasting and its impact on health
8
作者 Nurul Fadhilah Kamalul Aripin NIdayu Zahid +4 位作者 Mohd Aizat Abdul Rahim Hashim Yaacob Parvez I.Haris Zubaidah Haji AbdRahim Rauzah Hashim 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期50-64,共15页
Human saliva is an indispensable fluid that maintains a healthy oral cavity which otherwise can lead to oral diseases(dental caries and periodontitis).In addition,salivary metabolites and microbiome profile provide ea... Human saliva is an indispensable fluid that maintains a healthy oral cavity which otherwise can lead to oral diseases(dental caries and periodontitis).In addition,salivary metabolites and microbiome profile provide early detection of systemic diseases such as cancer and obesity.Salivary diagnostic has gained popularity due to its non-invasive sampling technique.Fasting(abstinence from food or drink or both)research for weight loss and improve health is common,but studies using fasting saliva are scarce.Some metabolites in fasting saliva have been reported with interesting results,which can be enhanced by considering different confounding factors.For example,fasting saliva contains higher salivary nitrite,which is related to nitric oxide(NO).NO is a vasodilator supporting the healthy function of endothelial cells and its deficiency is connected to many diseases.The timely supply of NO through exogenous and endogenous means is highlighted and the potential advantage of fasting salivary composition changes in relation to COVID-19 infection is speculated.This review aims to provide a general discussion on the salivary composition,properties,and functions of the whole saliva,including the health benefits of fasting. 展开更多
关键词 SALIVA fastING NITRATE NITRITE Nitric oxide
下载PDF
Mechanistic insights into fasting-induced autophagy in the aging heart
9
作者 Hannaneh Parvaresh Katarzyna Paczek +1 位作者 Md Abdul Alim Al-Bari Nabil Eid 《World Journal of Cardiology》 2024年第3期109-117,共9页
Autophagy is a prosurvival mechanism for the clearance of accumulated abnormal proteins,damaged organelles,and excessive lipids within mammalian cells.A growing body of data indicates that autophagy is reduced in agin... Autophagy is a prosurvival mechanism for the clearance of accumulated abnormal proteins,damaged organelles,and excessive lipids within mammalian cells.A growing body of data indicates that autophagy is reduced in aging cells.This reduction leads to various diseases,such as myocardial hypertrophy,infarction,and atherosclerosis.Recent studies in animal models of an aging heart showed that fasting-induced autophagy improved cardiac function and longevity.This improvement is related to autophagic clearance of damaged cellular components via either bulk or selective autophagy(such as mitophagy).In this editorial,we summarize the mechanisms of autophagy in normal and aging hearts.In addition,the protective effect of fasting-induced autophagy in cardiac aging has been highlighted. 展开更多
关键词 AGING AUTOPHAGY HEART fastING MITOPHAGY
下载PDF
Fasting and Cancer: Practice and Patients’ Quality of Life during Ramadan
10
作者 Oumaima Talbi Zineb Benbrahim +6 位作者 Khadija Hinaje Imad Chakri Kaoutar Maadin Lamiae Amaadour Karima Oualla Samia Arifi Nawfel Mellas 《Journal of Cancer Therapy》 2024年第3期49-56,共8页
Introduction: Ramadan is the ninth lunar month of the Muslim calendar, and fasting during Ramadan is one of the five pillars of Islam. Muslim cancer patients and health professionals are faced with a dilemma between t... Introduction: Ramadan is the ninth lunar month of the Muslim calendar, and fasting during Ramadan is one of the five pillars of Islam. Muslim cancer patients and health professionals are faced with a dilemma between the necessity of fasting and its possible adverse effects during Ramadan on the health status of cancer patients. We believe that addressing the issue of fasting in cancer patients is of global interest. Objectives: Prevalence of fasting in cancer patients during Ramadan;Predictive factors of Ramadan fasting in cancer patients;The effect of fasting during Ramadan on the quality of life of cancer patients. Materials and Methods: A structured questionnaire was used to interview adult cancer patients who received chemotherapy IV—or oral treatment at the medical oncology department at the Hassan II University Hospital in Fez during the month of Ramadan 1443 Hijri (April to May 2022). The quality of cancer patients’ lives during their fasting practice in Ramadan was evaluated via the QLQ-C30 questionnaires. Results: 48% of patients did not fast during Ramadan, 22% and 30% were partial and complete fasters respectively. Patients, with OMS 0 to 1, who receive outpatient treatment, non-metastatic patients and patients on oral treatment were more frequent in the completely fasted group. All these factors showed statistically significant values (p < 0.05). 44% of patients sought advice from the treating oncologist if they could fast, while only 15% of patients during Ramadan asked an imam if they could be excused from fasting. A comparison of the QLQ-C30 data showed a significant improvement in emotional functioning with fasting, however, patients had clinically more but not significantly fatigue after fasting. Conclusion: Female gender, good WHO, non-metastatic disease, and oral or outpatient treatment were more likely to be fasting. This study argues that fasting did not influence the quality of life, and appears to significantly improve emotional functioning in cancer patients during Ramadan. 展开更多
关键词 RAMADAN fastING Quality of Life PRACTICE
下载PDF
A fast forward computational method for nuclear measurement using volumetric detection constraints
11
作者 Qiong Zhang Lin-Lv Lin 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期47-63,共17页
Owing to the complex lithology of unconventional reservoirs,field interpreters usually need to provide a basis for interpretation using logging simulation models.Among the various detection tools that use nuclear sour... Owing to the complex lithology of unconventional reservoirs,field interpreters usually need to provide a basis for interpretation using logging simulation models.Among the various detection tools that use nuclear sources,the detector response can reflect various types of information of the medium.The Monte Carlo method is one of the primary methods used to obtain nuclear detection responses in complex environments.However,this requires a computational process with extensive random sampling,consumes considerable resources,and does not provide real-time response results.Therefore,a novel fast forward computational method(FFCM)for nuclear measurement that uses volumetric detection constraints to rapidly calculate the detector response in various complex environments is proposed.First,the data library required for the FFCM is built by collecting the detection volume,detector counts,and flux sensitivity functions through a Monte Carlo simulation.Then,based on perturbation theory and the Rytov approximation,a model for the detector response is derived using the flux sensitivity function method and a one-group diffusion model.The environmental perturbation is constrained to optimize the model according to the tool structure and the impact of the formation and borehole within the effective detection volume.Finally,the method is applied to a neutron porosity tool for verification.In various complex simulation environments,the maximum relative error between the calculated porosity results of Monte Carlo and FFCM was 6.80%,with a rootmean-square error of 0.62 p.u.In field well applications,the formation porosity model obtained using FFCM was in good agreement with the model obtained by interpreters,which demonstrates the validity and accuracy of the proposed method. 展开更多
关键词 Nuclear measurement fast forward computation Volumetric constraints
下载PDF
Fast compressed sensing spectral measurement with adaptive gradient multiscale resolution
12
作者 蓝若明 刘雪峰 +1 位作者 李天平 白成杰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期298-304,共7页
We propose a fast,adaptive multiscale resolution spectral measurement method based on compressed sensing.The method can apply variable measurement resolution over the entire spectral range to reduce the measurement ti... We propose a fast,adaptive multiscale resolution spectral measurement method based on compressed sensing.The method can apply variable measurement resolution over the entire spectral range to reduce the measurement time by over 75%compared to a global high-resolution measurement.Mimicking the characteristics of the human retina system,the resolution distribution follows the principle of gradually decreasing.The system allows the spectral peaks of interest to be captured dynamically or to be specified a priori by a user.The system was tested by measuring single and dual spectral peaks,and the results of spectral peaks are consistent with those of global high-resolution measurements. 展开更多
关键词 SPECTROMETER compressed sensing adaptive gradient multiscale resolution fast measurement
下载PDF
Unraveling the Fundamental Mechanism of Interface Conductive Network Influence on the Fast‑Charging Performance of SiO‑Based Anode for Lithium‑Ion Batteries
13
作者 Ruirui Zhang Zhexi Xiao +6 位作者 Zhenkang Lin Xinghao Yan Ziying He Hairong Jiang Zhou Yang Xilai Jia Fei Wei 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期53-68,共16页
Progress in the fast charging of high-capacity silicon monoxide(SiO)-based anode is currently hindered by insufficient conductivity and notable volume expansion.The construction of an interface conductive network effe... Progress in the fast charging of high-capacity silicon monoxide(SiO)-based anode is currently hindered by insufficient conductivity and notable volume expansion.The construction of an interface conductive network effectively addresses the aforementioned problems;however,the impact of its quality on lithium-ion transfer and structure durability is yet to be explored.Herein,the influence of an interface conductive network on ionic transport and mechanical stability under fast charging is explored for the first time.2D modeling simulation and Cryo-transmission electron microscopy precisely reveal the mitigation of interface polarization owing to a higher fraction of conductive inorganic species formation in bilayer solid electrolyte interphase is mainly responsible for a linear decrease in ionic diffusion energy barrier.Furthermore,atomic force microscopy and Raman shift exhibit substantial stress dissipation generated by a complete conductive network,which is critical to the linear reduction of electrode residual stress.This study provides insights into the rational design of optimized interface SiO-based anodes with reinforced fast-charging performance. 展开更多
关键词 fast charging SiO anode Interface conductive network Ionic transport Mechanical stability
下载PDF
Dual-single-atoms of Pt-Co boost sulfur redox kinetics for ultrafast Li-S batteries
14
作者 Hanyan Wu Xuejie Gao +7 位作者 Xinyang Chen Weihan Li Junjie Li Lei Zhang Yang Zhao Ming Jiang Runcang Sun Xueliang Sun 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期53-63,共11页
Applications of lithium-sulfur(Li-S)batteries are still limited by the sluggish conversion kinetics from polysulfide to Li_(2)S.Although various single-atom catalysts are available for improving the conversion kinetic... Applications of lithium-sulfur(Li-S)batteries are still limited by the sluggish conversion kinetics from polysulfide to Li_(2)S.Although various single-atom catalysts are available for improving the conversion kinetics,the sulfur redox kinetics for Li-S batteries is still not ultrafast.Herein,in this work,a catalyst with dual-single-atom Pt-Co embedded in N-doped carbon nanotubes(Pt&Co@NCNT)was proposed by the atomic layer deposition method to suppress the shuttle effect and synergistically improve the interconversion kinetics from polysulfides to Li_(2)S.The X-ray absorption near edge curves indicated the reversible conversion of Li_(2)Sx on the S/Pt&Co@NCNT electrode.Meanwhile,density functional theory demonstrated that the Pt&Co@NCNT promoted the free energy of the phase transition of sulfur species and reduced the oxidative decomposition energy of Li_(2)S.As a result,the batteries assembled with S/Pt&Co@NCNT electrodes exhibited a high capacity retention of 80%at 100 cycles at a current density of 1.3 mA cm^(−2)(S loading:2.5 mg cm^(−2)).More importantly,an excellent rate performance was achieved with a high capacity of 822.1 mAh g^(−1) at a high current density of 12.7 mA cm^(−2).This work opens a new direction to boost the sulfur redox kinetics for ultrafast Li-S batteries. 展开更多
关键词 DFT calculation dual-single-atoms of Pt-Co fast Li-sulfur batteries sulfur redox kinetics XANES analysis
下载PDF
基于数据驱动的FAST主动反射面调节优化模型
15
作者 吕茏 陈浩 +3 位作者 吴建鑫 刘亚兰 邓依兰 范小林 《贵州大学学报(自然科学版)》 2024年第1期64-71,共8页
针对500 m口径球面射电望远镜(five-hundred-meter aperture spherical radio telescope,FAST)的主动反射面调节问题,利用旋转抛物面在三维空间中的定义建立了一个对任意天体角度均适用的工作抛物面方程,该方法不同于以往的坐标旋转的... 针对500 m口径球面射电望远镜(five-hundred-meter aperture spherical radio telescope,FAST)的主动反射面调节问题,利用旋转抛物面在三维空间中的定义建立了一个对任意天体角度均适用的工作抛物面方程,该方法不同于以往的坐标旋转的方法。利用反射面板重心点作为反射点,将反射接收比定义为能把光线反射到馈源舱被其接收的面板数量与300 m口径工作抛物面下总面板数量的比值。结合主索节点径向伸缩距离、边界平稳过度和邻接距离变化幅度三个约束条件,以接收比最大化作为目标函数,建立了一个工作抛物面优化模型,并利用节点数据和模拟退火算法对其进行求解,得到了工作理想抛物面。选用两组天体角度进行实例分析,结果显示调节后的接收比增大12.82%,并给出了工作主索节点的部分径向调节方案。本研究为FAST对于任意天体角度的变形提供了一种新的建模方法,也对馈源舱反射接收比提出了一种新的计算方式。 展开更多
关键词 fast主动反射面 旋转抛物面 馈源舱接收比 优化模型 模拟退火算法
下载PDF
Improving path planning efficiency for underwater gravity-aided navigation based on a new depth sorting fast search algorithm
16
作者 Xiaocong Zhou Wei Zheng +2 位作者 Zhaowei Li Panlong Wu Yongjin Sun 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期285-296,共12页
This study focuses on the improvement of path planning efficiency for underwater gravity-aided navigation.Firstly,a Depth Sorting Fast Search(DSFS)algorithm was proposed to improve the planning speed of the Quick Rapi... This study focuses on the improvement of path planning efficiency for underwater gravity-aided navigation.Firstly,a Depth Sorting Fast Search(DSFS)algorithm was proposed to improve the planning speed of the Quick Rapidly-exploring Random Trees*(Q-RRT*)algorithm.A cost inequality relationship between an ancestor and its descendants was derived,and the ancestors were filtered accordingly.Secondly,the underwater gravity-aided navigation path planning system was designed based on the DSFS algorithm,taking into account the fitness,safety,and asymptotic optimality of the routes,according to the gravity suitability distribution of the navigation space.Finally,experimental comparisons of the computing performance of the ChooseParent procedure,the Rewire procedure,and the combination of the two procedures for Q-RRT*and DSFS were conducted under the same planning environment and parameter conditions,respectively.The results showed that the computational efficiency of the DSFS algorithm was improved by about 1.2 times compared with the Q-RRT*algorithm while ensuring correct computational results. 展开更多
关键词 Depth Sorting fast Search algorithm Underwater gravity-aided navigation Path planning efficiency Quick Rapidly-exploring Random Trees*(QRRT*)
下载PDF
基于FAST-FAHP理论的洗鞋机设计研究
17
作者 张路 杨艳红 周红生 《沈阳工程学院学报(自然科学版)》 2024年第1期89-96,共8页
为改善用户的脚部健康问题,探索彻底清洁鞋子的方法,提出一种FAHP(模糊层次分析法)和FAST(功能分析系统技术法)相结合的研究方法。首先,通过FAHP进行用户需求分析,创建模糊判断矩阵,求得权重值;其次,根据FAST将产品功能与用户需求相结合... 为改善用户的脚部健康问题,探索彻底清洁鞋子的方法,提出一种FAHP(模糊层次分析法)和FAST(功能分析系统技术法)相结合的研究方法。首先,通过FAHP进行用户需求分析,创建模糊判断矩阵,求得权重值;其次,根据FAST将产品功能与用户需求相结合,创建功能树并进行功能分析;最后,将权重值和产品功能树相结合,设计出一款方便用户使用的鞋子清洗产品。整体上实现从需求到功能再到具体产品设计的理论探索,以及洗鞋机从原理、外观、结构等方面的可行性验证,完成从理论到实践的具体性要求。FAST-FAHP理论模式和产品具体设计的结合,有利于设计师在具体产品设计中针对大量的用户需求寻求设计侧重点,从而帮助设计师在实际设计中更加科学、有效地进行设计活动。 展开更多
关键词 工业设计 模糊层次分析法 功能分析系统技术法 洗鞋机
下载PDF
Intermittent fasting boosts antitumor immunity by restricting CD11b^(+)Ly6C^(low)Ly6G^(low) cell viability through glucose metabolism in murine breast tumor model
18
作者 Chenghao Fu Zhehao Liang +13 位作者 Zemiao Niu Ning Chen Yuemin Li Zhenhua Liang Yanwei Huo Hao Xi Rong Wang Yonghuan Yan Xiaoruo Gan Mengtian Wang Yun Huang Yan Zhang Mingming Gao Pin Lü 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2327-2345,共19页
Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy.However,it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting.Herein we observed ... Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy.However,it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting.Herein we observed that two cycles of fasting treatment significantly inhibited breast tumor growth and lung tissue metastasis,as well as prolonged overall survival in mice bearing 4T1 and 4T07 breast cancer.During this process,both the immunosuppressive monocytic-(M-)and granulocytic-(G-)myeloid-derived suppressor cell(MDSC)decreased,accompanied by an increase in interleukin(IL)7R^(+)and granzyme B^(+)T cells in the tumor microenvironment.Interestingly,we observed that Ly6G^(low)G-MDSC sharply decreased after fasting treatment,and the cell surface markers and protein mass spectrometry data showed potential therapeutic targets.Mechanistic investigation revealed that glucose metabolism restriction suppressed the splenic granulocytemonocyte progenitor and the generation of colony-stimulating factors and IL-6,which both contributed to the accumulation of G-MDSC.On the other hand,glucose metabolism restriction can directly induce the apoptosis of Ly6G^(low)G-MDSC,but not Ly6G^(high)subsets.In summary,these results suggest that glucose metabolism restriction induced by fasting treatment attenuates the immune-suppressive milieu and enhances the activation of CD3^(+)T cells,providing potential solutions for enhancing immune-based cancer interventions. 展开更多
关键词 Intermittent fasting Ly6G^(low)myeloid-derived suppressor cell apoptosis Extramedullary hematopoiesis Colony stimulating factor Glucose metabolism restriction
下载PDF
基于FAST算法的核动力旋转机械故障诊断
19
作者 宋怡 《机械设计与制造工程》 2024年第4期56-60,共5页
基于FAST算法设计了核动力旋转机械故障诊断方法。提取候选区故障特征,在卷积层内输出候选区向量,通过计算图像尺寸得到候选区内故障特征函数值;基于FAST算法标记旋转机械故障点,对最大池化值与最小池化值进行计算,得到标准层的梯度收... 基于FAST算法设计了核动力旋转机械故障诊断方法。提取候选区故障特征,在卷积层内输出候选区向量,通过计算图像尺寸得到候选区内故障特征函数值;基于FAST算法标记旋转机械故障点,对最大池化值与最小池化值进行计算,得到标准层的梯度收敛情况;设计了核动力旋转机械故障诊断算法,得到旋转机械故障诊断方法。对比4种不同旋转机械故障诊断方法的实验结果可知,针对6种不同的故障特征,基于FAST算法的核动力旋转机械故障诊断方法的对数似然率均为最大,诊断准确率更高。 展开更多
关键词 特征点提取算法 核动力 旋转机械 机械故障 故障检测
下载PDF
基于改进Fast-DTW的多维地磁序列匹配算法研究
20
作者 姚霆宇 余学祥 +1 位作者 韩雨辰 朱平 《现代信息科技》 2024年第8期89-92,96,共5页
传统单点的地磁匹配定位算法运算量大,且定位时效性及定位精度较差。针对该问题,采用基于序列的快速动态时间规整算法Fast-DTW实现多维的地磁序列匹配,并利用最长公共子序列LCS的有序聚类进行优化。离线阶段通过坐标转换法构建四维地磁... 传统单点的地磁匹配定位算法运算量大,且定位时效性及定位精度较差。针对该问题,采用基于序列的快速动态时间规整算法Fast-DTW实现多维的地磁序列匹配,并利用最长公共子序列LCS的有序聚类进行优化。离线阶段通过坐标转换法构建四维地磁指纹库,在线阶段进行实时地磁序列匹配,获得定位结果。实验结果表明,该算法的定位时效性及精度均有提升。 展开更多
关键词 地磁室内定位 快速动态时间规整算法 最长公共子序列 地磁指纹库
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部