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Sequential Analysis in the Identification of 3rd Order System Tract in the Abidjan Margin
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作者 Blandine Akissi Egoran N’guessan Donald Ahoure +2 位作者 Fori Yao Paul Assalé Sylvain Mondé Loukou Victor N’da 《Open Journal of Applied Sciences》 2024年第6期1474-1489,共16页
The use of sequential stratigraphy concept, based on well logs, sedimentology, and biostratigraphy, has shed light on the complex mechanisms controlling sedimentary accumulations. Consequently, identifying these mecha... The use of sequential stratigraphy concept, based on well logs, sedimentology, and biostratigraphy, has shed light on the complex mechanisms controlling sedimentary accumulations. Consequently, identifying these mechanisms allows us to predict the hydrocarbon generation potential of source rocks. In the Ivorian offshore sedimentary basin, certain studies have contributed to understanding and characterizing the petroleum system. However, these previous works did not integrate biostratigraphic data to highlight sedimentary facies. This study, conducted on two wells in the Abidjan margin, is crucial as it helps us comprehend the geometry of fossil sediments in relation to sea level variations. It will also aid in reconstructing the basin-filling history and predicting the distribution of rocks capable of trapping oil, determining lowstand systems tracts (reservoir rocks), transgressive systems tracts, and highstand systems tracts (cap rocks). Lithological analysis revealed predominantly clayey sedimentation with sandy layers. Well log data facilitated the delineation of formation boundaries and highlighted reservoirs consisting of sands, sandstones, limestones, and occasionally intercalated shales. Integrating these analysis results with biostratigraphic interpretations based on foraminifera and palynomorphs revealed that the traversed formations were deposited in a transitional environment ranging from Coniacian to Maastrichtian ages. Applying sequential stratigraphy concept from well logging resolved dating issues encountered in microfossil-poor or microfossil-free zones. The results of the Coniacian-Maastrichtian age sequential subdivision were aligned with the chart. 展开更多
关键词 Sequence Stratigraphy systems Tracts Senonian Côte d’Ivoire
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考虑频率耦合特性的D-PMSG复数域阻抗建模及其特征分析
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作者 苏晨博 刘崇茹 +2 位作者 王瑾媛 郝琪 董浩云 《电力系统自动化》 EI CSCD 北大核心 2024年第10期118-128,共11页
阻抗分析法因其简单有效被广泛用于含电力电子变换器的互联系统稳定性研究。然而,采用传统方法对频域序阻抗建模时,需通过非线性变换(Park变换及其反变换)进行坐标系转换,这会导致不同周期分量的卷积运算及相应的频移,其过程较为烦琐。... 阻抗分析法因其简单有效被广泛用于含电力电子变换器的互联系统稳定性研究。然而,采用传统方法对频域序阻抗建模时,需通过非线性变换(Park变换及其反变换)进行坐标系转换,这会导致不同周期分量的卷积运算及相应的频移,其过程较为烦琐。针对上述问题,基于复向量时域微分算子,提出了永磁直驱同步发电机(D-PMSG)等效阻抗建模方法。该方法在时域周期系统稳定运行轨迹的邻域内直接进行小信号线性化,并采用指数旋转因子灵活反映系统受扰后的时变特性,结合时域微分算子等效表征互联系统控制环节的动态特性,避免了频域阻抗建模时坐标系的反复变换,大幅降低了解析建模的复杂度。此外,所提方法能够更加清晰地阐释互联系统受到扰动时D-PMSG并网逆变器产生频率耦合现象的物理意义;同时,能够说明基频电压初始相位对耦合分量相频特性的影响。最后,利用仿真验证了所提算法的有效性。 展开更多
关键词 复向量 阻抗建模 永磁直驱同步发电机(d-PMSG) 频率耦合 系统稳定性分析
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基于1DCNN和D-S多信息融合的光伏系统直流母线串联电弧故障检测
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作者 李岩 刘鑫月 +2 位作者 乔俊杰 王毛桃 王鹏 《电工电能新技术》 CSCD 北大核心 2024年第5期58-67,共10页
直流母线是光伏系统输出能源的主干道,由于长期曝晒、风化等作用,电缆、连接器等组件劣化,光伏系统直流母线中发生电弧的可能性急剧上升,极易引发火灾、触电等事故。在光伏系统中,串联电弧故障将使回路电流下降,传统的过流保护无法识别... 直流母线是光伏系统输出能源的主干道,由于长期曝晒、风化等作用,电缆、连接器等组件劣化,光伏系统直流母线中发生电弧的可能性急剧上升,极易引发火灾、触电等事故。在光伏系统中,串联电弧故障将使回路电流下降,传统的过流保护无法识别。因此,本文提出基于深度学习和证据理论(D-S)的方法来识别串联电弧故障,该方法基于并联电容器电流和电压信号,采用一维卷积神经网络(1DCNN)对检测数据进行电弧识别;在此基础上将基于单个传感数据的识别结果作为证据,运用D-S多信息合成法则计算得到信度分配,最后利用决策规则判断是否发生串联电弧故障。搭建多参数可调模型获取数据进行测试,结果表明:使用1DCNN识别方法,基于并联电容器电流和电压信号的串联电弧识别准确率分别为97.19%和94.98%,而基于1DCNN和D-S多信息融合的光伏系统直流串联电弧故障检测的识别准确率可提升至99%以上。 展开更多
关键词 光伏系统 1dCNN 串联电弧故障 d-S多元信息融合 故障检测
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基于加权D-S证据理论的旋翼故障诊断
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作者 高亚东 张传壮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第1期66-75,共10页
旋翼作为直升机的升力面和操作面,其健康状态对直升机的安全至关重要。旋翼故障诊断技术仍是直升机健康与使用监测系统(Health and usage monitoring system, HUMS)领域的薄弱环节,开发旋翼故障诊断技术具有重要价值。基于信息融合技术... 旋翼作为直升机的升力面和操作面,其健康状态对直升机的安全至关重要。旋翼故障诊断技术仍是直升机健康与使用监测系统(Health and usage monitoring system, HUMS)领域的薄弱环节,开发旋翼故障诊断技术具有重要价值。基于信息融合技术,首先分析了旋翼故障的诊断机理,建立了旋翼故障模型,通过流固耦合仿真获取了不同故障下桨叶、轮毂和机身的故障特征信息,生成数据集进行网络训练和验证。然后,利用遗传算法反向传播(Genetic algorithm-backpropagation, GA-BP)优化神经网络诊断3种类型的直升机旋翼故障,即后缘调整片误调、变距拉杆误调和桨叶质量不平衡。3个逐级神经网络分别对旋翼故障类型、故障位置和故障程度进行了诊断识别。最后采用加权的Dempster-Shafer(D-S)证据理论对旋翼故障进行诊断和分析。结果证明基于改进D-S证据理论的旋翼故障诊断方法能够成功应用到旋翼故障诊断中,并具有良好的识别效果。 展开更多
关键词 旋翼系统 故障诊断 GA-BP神经网络 信息融合技术 d-S证据理论
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μ ANALYSIS AND μ SYNTHESIS FOR NONLINEAR ROBUST CONTROL SYSTEMS 被引量:2
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作者 Wu Min Peng Zhihong Tang Chaohui Gui Weihua(College of Information Engineering, Central South University of Technology, Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 1998年第1期69-74,共6页
μANALYSISANDμSYNTHESISFORNONLINEARROBUSTCONTROLSYSTEMS*WuMinPengZhihongTangChaohuiGuiWeihua(ColegeofInformat... μANALYSISANDμSYNTHESISFORNONLINEARROBUSTCONTROLSYSTEMS*WuMinPengZhihongTangChaohuiGuiWeihua(ColegeofInformationEngineering,Ce... 展开更多
关键词 NONLINEAR systems uncertainty ROBUST CONTROL μ analysis μ synthesis linear FRACTIONAL transformation dK ITERATION
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3D Modelling of Biological Systems for Biomimetics 被引量:2
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作者 Kevin Hapeshi Ashok K.Bhattacharya 《Journal of Bionic Engineering》 SCIE EI CSCD 2004年第1期20-40,共21页
With the advanced development of computer-based enabling technologies, many engineering, medical, biology, chemistry, physics and food science etc have developed to the unprecedented levels, which lead to many researc... With the advanced development of computer-based enabling technologies, many engineering, medical, biology, chemistry, physics and food science etc have developed to the unprecedented levels, which lead to many research and development interests in various multi-discipline areas. Among them, biomimetics is one of the most promising and attractive branches of study. Biomimetics is a branch of study that uses biological systems as a model to develop synthetic systems. To learn from nature, one of the fundamental issues is to understand the natural systems such animals, insects, plants and human beings etc. The geometrical characterization and representation of natural systems is an important fundamental work for biomimetics research. 3D modeling plays a key role in the geometrical characterization and representation, especially in computer graphical visualization. This paper firstly presents the typical procedure of 3D modelling methods and then reviews the previous work of 3D geometrical modelling techniques and systems developed for industrial, medical and animation applications. Especially the paper discusses the problems associated with the existing techniques and systems when they are applied to 3D modelling of biological systems. Based upon the discussions, the paper proposes some areas of research interests in 3D modelling of biological systems and for Biomimetics. 展开更多
关键词 biomimetics 3d modelling 3d scanners 3d geometry computation biological systems
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Feedback iterative learning control for time-delay systems based on 2D analysis approach 被引量:3
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作者 Deyuan MENG Yingmin JIA +1 位作者 Junping DU Shiying YUAN 《控制理论与应用(英文版)》 EI 2010年第4期457-463,共7页
This paper deals with the iterative learning control (ILC) design for multiple-input multiple-output (MIMO),time-delay systems (TDS).Two feedback ILC schemes are considered using the so-called two-dimensional ... This paper deals with the iterative learning control (ILC) design for multiple-input multiple-output (MIMO),time-delay systems (TDS).Two feedback ILC schemes are considered using the so-called two-dimensional (2D) analysis approach.It shows that continuous-discrete 2D Roesser systems can be developed to describe the entire learning dynamics of both ILC schemes,based on which necessary and sufficient conditions for their stability can be provided.A numerical example is included to validate the theoretical analysis. 展开更多
关键词 Iterative learning control Time-delay systems 2d analysis approach
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From oral formulations to drug-eluting implants:using 3D and 4D printing to develop drug delivery systems and personalized medicine 被引量:2
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作者 Niels G.A.Willemen Margaretha A.J.Morsink +4 位作者 Devin Veerman Classius F.da Silva Juliana C.Cardoso Eliana B.Souto Patrícia Severino 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2022年第1期85-106,共22页
Since the start of the Precision Medicine Initiative by the United States of America in 2015,interest in personalized medicine has grown extensively.In short,personalized medicine is a term that describes medical trea... Since the start of the Precision Medicine Initiative by the United States of America in 2015,interest in personalized medicine has grown extensively.In short,personalized medicine is a term that describes medical treatment that is tuned to the individual.One possible way to realize personalized medicine is 3D printing.When using materials that can be tuned upon stimulation,4D printing is established.In recent years,many studies have been exploring a new field that combines 3D and 4D printing with therapeutics.This has resulted in many concepts of pharmaceutical devices and formulations that can be printed and,possibly,tailored to an individual.Moreover,the first 3D printed drug,Spritam®,has already found its way to the clinic.This review gives an overview of various 3D and 4D printing techniques and their applications in the pharmaceutical field as drug delivery systems and personalized medicine. 展开更多
关键词 drug delivery systems 3d/4d printing drug-eluting implants MICRONEEdLES Oral formulations
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3D Reconstruction for Motion Blurred Images Using Deep Learning-Based Intelligent Systems 被引量:3
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作者 Jing Zhang Keping Yu +2 位作者 Zheng Wen Xin Qi Anup Kumar Paul 《Computers, Materials & Continua》 SCIE EI 2021年第2期2087-2104,共18页
The 3D reconstruction using deep learning-based intelligent systems can provide great help for measuring an individual’s height and shape quickly and accurately through 2D motion-blurred images.Generally,during the a... The 3D reconstruction using deep learning-based intelligent systems can provide great help for measuring an individual’s height and shape quickly and accurately through 2D motion-blurred images.Generally,during the acquisition of images in real-time,motion blur,caused by camera shaking or human motion,appears.Deep learning-based intelligent control applied in vision can help us solve the problem.To this end,we propose a 3D reconstruction method for motion-blurred images using deep learning.First,we develop a BF-WGAN algorithm that combines the bilateral filtering(BF)denoising theory with a Wasserstein generative adversarial network(WGAN)to remove motion blur.The bilateral filter denoising algorithm is used to remove the noise and to retain the details of the blurred image.Then,the blurred image and the corresponding sharp image are input into the WGAN.This algorithm distinguishes the motion-blurred image from the corresponding sharp image according to the WGAN loss and perceptual loss functions.Next,we use the deblurred images generated by the BFWGAN algorithm for 3D reconstruction.We propose a threshold optimization random sample consensus(TO-RANSAC)algorithm that can remove the wrong relationship between two views in the 3D reconstructed model relatively accurately.Compared with the traditional RANSAC algorithm,the TO-RANSAC algorithm can adjust the threshold adaptively,which improves the accuracy of the 3D reconstruction results.The experimental results show that our BF-WGAN algorithm has a better deblurring effect and higher efficiency than do other representative algorithms.In addition,the TO-RANSAC algorithm yields a calculation accuracy considerably higher than that of the traditional RANSAC algorithm. 展开更多
关键词 3d reconstruction motion blurring deep learning intelligent systems bilateral filtering random sample consensus
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Efficient Hardware Design of a Secure Cancellable Biometric Cryptosystem
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作者 Lamiaa A.Abou Elazm Walid El-Shafai +6 位作者 Sameh Ibrahim Mohamed G.Egila H.Shawkey Mohamed K.H.Elsaid Naglaa F.Soliman Hussah Nasser AlEisa Fathi E.Abd El-Samie 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期929-955,共27页
Biometric security is a growing trend,as it supports the authentication of persons using confidential biometric data.Most of the transmitted data in multi-media systems are susceptible to attacks,which affect the secur... Biometric security is a growing trend,as it supports the authentication of persons using confidential biometric data.Most of the transmitted data in multi-media systems are susceptible to attacks,which affect the security of these sys-tems.Biometric systems provide sufficient protection and privacy for users.The recently-introduced cancellable biometric recognition systems have not been investigated in the presence of different types of attacks.In addition,they have not been studied on different and large biometric datasets.Another point that deserves consideration is the hardware implementation of cancellable biometric recognition systems.This paper presents a suggested hybrid cancellable biometric recognition system based on a 3D chaotic cryptosystem.The rationale behind the utilization of the 3D chaotic cryptosystem is to guarantee strong encryption of biometric templates,and hence enhance the security and privacy of users.The suggested cryptosystem adds significant permutation and diffusion to the encrypted biometric templates.We introduce some sort of attack analysis in this paper to prove the robustness of the proposed cryptosystem against attacks.In addition,a Field Programmable Gate Array(FPGA)implementation of the pro-posed system is introduced.The obtained results with the proposed cryptosystem are compared with those of the traditional encryption schemes,such as Double Random Phase Encoding(DRPE)to reveal superiority,and hence high recogni-tion performance of the proposed cancellable biometric recognition system.The obtained results prove that the proposed cryptosystem enhances the security and leads to better efficiency of the cancellable biometric recognition system in the presence of different types of attacks. 展开更多
关键词 Information security cancellable biometric recognition systems CRYPTANALYSIS 3d chaotic map ENCRYPTION FPGA
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A Variational Approach for Numerically Solving the Two-Component Radial Dirac Equation for One-Particle Systems 被引量:2
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作者 Antonio L. A. Fonseca Daniel L. Nascimento +1 位作者 Fabio F. Monteiro Marco A. Amato 《Journal of Modern Physics》 2012年第4期350-354,共5页
In this paper we propose a numerical approach to solve the relativistic Dirac equation suitable for computational calculations of one-electron systems. A variational procedure is carried out similar to the well-known ... In this paper we propose a numerical approach to solve the relativistic Dirac equation suitable for computational calculations of one-electron systems. A variational procedure is carried out similar to the well-known Hylleraas computational method. An application of the method to hydrogen isoelectronic atoms is presented, showing its consistency and high accuracy, relative to the exact analytical eigenvalues. 展开更多
关键词 ONE-ELECTRON systems 2d dIRAC Equation No-Inertial Frames Variational Approach
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常见自身免疫性疾病患者血清25-羟维生素D水平的差异分析
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作者 张彪 曾丽娥 +4 位作者 卢鑫鑫 黄肖利 陈少婷 梅端容 江华 《检验医学与临床》 CAS 2024年第7期895-899,共5页
目的分析常见自身免疫性疾病患者血清25-羟维生素D[25(OH)D]水平差异及25(OH)D水平与其他实验室指标的相关性。方法选取2022年9月至2023年4月于福建省立医院风湿免疫科就诊的自身免疫性疾病患者229例作为试验组,其中系统性红斑狼疮(SLE... 目的分析常见自身免疫性疾病患者血清25-羟维生素D[25(OH)D]水平差异及25(OH)D水平与其他实验室指标的相关性。方法选取2022年9月至2023年4月于福建省立医院风湿免疫科就诊的自身免疫性疾病患者229例作为试验组,其中系统性红斑狼疮(SLE)58例、类风湿关节炎(RA)45例、干燥综合征(SS)37例、强直性脊柱炎(AS)60例、皮肌炎(DM)14例和系统性硬化症(SSc)15例;选择同期体检健康人群29例作为对照组。收集血清标本,采用高效液相色谱-串联质谱法对血清标本中的25(OH)D进行检测,分析25-羟维生素D_(2)[25(OH)D_(2)]、25-羟维生素D_(3)[25(OH)D_(3)]和总25(OH)D水平在常见自身免疫性疾病患者中的差异;分析总25(OH)D水平与其他实验室指标之间的相关性。结果试验组的血清总25(OH)D水平表现为缺乏或不足的比例总体上高于对照组。试验组的25(OH)D_(3)和总25(OH)D水平低于对照组,差异有统计学意义(P<0.05),试验组各疾病亚组25(OH)D_(3)、总25(OH)D水平比较,差异有统计学意义(P<0.05),SLE组25(OH)D_(3)和总25(OH)D水平最低,与SS组比较,差异有统计学意义(P<0.05)。女性患者的血清25(OH)D_(3)和总25(OH)D水平低于男性患者,差异有统计学意义(P<0.05)。SLE组血清总25(OH)D水平与红细胞沉降率(ESR)、肌酐(CREA)和尿素氮(BUN)呈负相关(P<0.05),RA组血清总25(OH)D水平与类风湿因子(RF)呈负相关(P<0.05),DM组总25(OH)D水平与ESR呈负相关(P<0.05)。结论自身免疫性疾病患者通常表现为维生素D缺乏或不足,且存在性别差异。在不同的自身免疫性疾病患者中血清总25(OH)D水平与ESR、CREA、BUN及RF表现出不同的相关性。 展开更多
关键词 自身免疫性疾病 25-羟维生素d 相关性 系统性红斑狼疮 类风湿关节炎 干燥综合征
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3D Physical Simulation of Water Flooding Characteristics of Buried Hill Reservoir with Different Fracture Systems 被引量:1
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作者 Xiaolin Zhu Zhiqiang Meng +2 位作者 Pingzhi Gong Guanglong Li Xinran Wang 《Journal of Power and Energy Engineering》 2020年第5期1-13,共13页
In order to understand the water-flooding characteristics of different fracture systems in metamorphic rock buried hill reservoirs and the mechanism of improving water-flooding development effect, a three-dimensional ... In order to understand the water-flooding characteristics of different fracture systems in metamorphic rock buried hill reservoirs and the mechanism of improving water-flooding development effect, a three-dimensional physical model of fractured reservoirs is established according to the similarity criterion based on the prototype of metamorphic buried hill reservoirs in JZ Oilfield in Bohai Bay Basin. Combined with the fractured reservoir characteristics of JZ Oilfield, the water displacement characteristics of the top-bottom staggered injection-production well pattern in different fracture network mode and different fracture development degree of buried hill reservoir are studied. The experimental results show that: 1) the more serious the fracture system irregularity is, the shorter the water-free oil production period is and the lower the water-free oil recovery is. After water breakthrough of production wells, the water cut rises faster, and the effect of water flooding development is worse;2) under the condition of non-uniform fracture development, the development effect of the bottom fracture undeveloped is better than that of the middle fracture undeveloped. Water injection wells are deployed in areas with relatively few fractures, while oil wells are deployed in fractured areas with higher oil recovery and better development effect. 展开更多
关键词 METAMORPHIC Buried HILL Reservoir dIFFERENT FRACTURE systems 3d Physical Simulation Water Flooding CHARACTERISTICS
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3D打印双雄会——Stratasys与3D Systems专利布局对比分析 被引量:4
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作者 薛亮 《中国发明与专利》 2013年第5期48-53,共6页
本文以3D打印行业的两大上市公司Stratasys和3D Systems为研究对象,简要介绍了两家企业的发展历史,并在基础专利、专利公开趋势、专利部署地域、技术侧重点、多产发明人、中国专利部署等方面对两家企业进行了对比分析,以期使读者能够初... 本文以3D打印行业的两大上市公司Stratasys和3D Systems为研究对象,简要介绍了两家企业的发展历史,并在基础专利、专利公开趋势、专利部署地域、技术侧重点、多产发明人、中国专利部署等方面对两家企业进行了对比分析,以期使读者能够初步了解两家企业的专利布局情况。 展开更多
关键词 3d打印 Stratasys 3d systems 基础专利 专利布局
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维生素D对脑内多巴胺神经系统的调节作用
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作者 王华林 赵旭东 +2 位作者 刘冉 李科 侯莉娟 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2024年第7期1530-1539,共10页
维生素D(vitamin D,VD)是一种神经活性类固醇,可以调节神经递质合成、维持细胞内钙稳态,在脑内发挥调节神经元兴奋性、保护神经细胞等作用。新近研究表明,VD与多巴胺(dopamine,DA)能神经元介导的动机、奖赏、学习和运动等行为有关,VD不... 维生素D(vitamin D,VD)是一种神经活性类固醇,可以调节神经递质合成、维持细胞内钙稳态,在脑内发挥调节神经元兴奋性、保护神经细胞等作用。新近研究表明,VD与多巴胺(dopamine,DA)能神经元介导的动机、奖赏、学习和运动等行为有关,VD不仅可促进DA合成,调节脑内DA水平,还从多种角度对DA能神经元发挥神经保护作用。本文将介绍VD的合成、代谢及作用途径,探讨VD对DA能神经元调控机制,为动机、奖赏等行为的研究提供理论参考。 展开更多
关键词 维生素d 多巴胺神经系统 调控功能 突触可塑性
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H_∞ Control for 2-D Discrete State Delayed Systems in the Second FM Model 被引量:3
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作者 XU Jian-Ming YU Li 《自动化学报》 EI CSCD 北大核心 2008年第7期809-813,共5页
这份报纸涉及 H 控制的问题为二维(2-D ) 分离州的延期系统由第二 Fornasini 和 Marchesini (FM ) 描述了州空间当模特儿。为这个 2-D 系统有 H 噪音变细的一个足够的条件以某个线性矩阵不平等(LMI ) 被给。最佳的 H 控制器被解决一个... 这份报纸涉及 H 控制的问题为二维(2-D ) 分离州的延期系统由第二 Fornasini 和 Marchesini (FM ) 描述了州空间当模特儿。为这个 2-D 系统有 H 噪音变细的一个足够的条件以某个线性矩阵不平等(LMI ) 被给。最佳的 H 控制器被解决一个凸的优化问题获得。最后,一个模拟例子被给说明建议结果的有效性。 展开更多
关键词 二维离散系统 控制方法 计算方法 自动化技术 智能系统
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D-stability and disturbance attenuation properties fornetworked control systems: switched system approach 被引量:2
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作者 Qiuxia Chen Andong Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第5期1108-1114,共7页
Both D-stability and finite L2-gain properties are studiedfor a class of uncertain discrete-time systems with timevaryingnetwork-induced delays. By using coordinate transformand delay partition, the D-stability and H... Both D-stability and finite L2-gain properties are studiedfor a class of uncertain discrete-time systems with timevaryingnetwork-induced delays. By using coordinate transformand delay partition, the D-stability and H∞ performance problemsfor such networked control systems (NCSs) are equivalentlytransferred into the corresponding problems for switching systemswith arbitrary switching. Then, a sufficient condition for the existenceof the robust D-stabilizing controllers is derived in termsof linear matrix inequality (LMI), and the design method is alsopresented for the state feedback controllers which guarantee thatall the closed-loop poles remain inside the specified disk D(α,r)and the desired disturbance attenuation level. Finally, an illustrativeexample is given to demonstrate the effectiveness of the proposedresults. 展开更多
关键词 d-STABILITY networked control system (NCS) H∞performance switching system.
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Local dose-dense chemotherapy for triple-negative breast cancer via minimally invasive implantation of 3D printed devices
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作者 Noehyun Myung Hyun-Wook Kang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2024年第1期69-85,共17页
Dose-dense chemotherapy is the preferred first-line therapy for triple-negative breast cancer(TNBC),a highly aggressive disease with a poor prognosis.This treatment uses the same drug doses as conventional chemotherap... Dose-dense chemotherapy is the preferred first-line therapy for triple-negative breast cancer(TNBC),a highly aggressive disease with a poor prognosis.This treatment uses the same drug doses as conventional chemotherapy but with shorter dosing intervals,allowing for promising clinical outcomes with intensive treatment.However,the frequent systemic administration used for this treatment results in systemic toxicity and low patient compliance,limiting therapeutic efficacy and clinical benefit.Here,we report local dose-dense chemotherapy to treat TNBC by implanting 3D printed devices with timeprogrammed pulsatile release profiles.The implantable device can control the time between drug releases based on its internal microstructure design,which can be used to control dose density.The device is made of biodegradable materials for clinical convenience and designed for minimally invasive implantation via a trocar.Dose density variation of local chemotherapy using programmable release enhances anti-cancer effects in vitro and in vivo.Under the same dose density conditions,device-based chemotherapy shows a higher anticancer effect and less toxic response than intratumoral injection.We demonstrate local chemotherapy utilizing the implantable device that simulates the drug dose,number of releases,and treatment duration of the dose-dense AC(doxorubicin and cyclophosphamide)regimen preferred for TNBC treatment.Dose density modulation inhibits tumor growth,metastasis,and the expression of drug resistance-related proteins,including p-glycoprotein and breast cancer resistance protein.To the best of our knowledge,local dose-dense chemotherapy has not been reported,and our strategy can be expected to be utilized as a novel alternative to conventional therapies and improve anti-cancer efficiency. 展开更多
关键词 dose-dense chemotherapy Triple-negative breast cancer 3d printing Pulsatile release Local drug delivery systems
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基于D-H法的农业采摘机器人运动协作控制系统设计 被引量:2
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作者 闵小翠 李鹏 《计算机测量与控制》 2024年第1期72-78,84,共8页
为提升农业采摘机器人运动协作控制性能,降低机器人碰撞概率,利用D-H法优化设计机器人运动协作控制系统;改装位置、力矩以及碰撞传感器设备,优化运动协作控制器与驱动器,调整系统通信模块结构,完成硬件系统的优化;利用D-H法构建农业采... 为提升农业采摘机器人运动协作控制性能,降低机器人碰撞概率,利用D-H法优化设计机器人运动协作控制系统;改装位置、力矩以及碰撞传感器设备,优化运动协作控制器与驱动器,调整系统通信模块结构,完成硬件系统的优化;利用D-H法构建农业采摘机器人数学模型,在该模型下,利用传感器设备实现机器人实时位姿的量化描述,通过机器人采摘流程的模拟,分配机器人运动协作任务,从位置和姿态等多个方面,确定运动协作控制目标,经过受力分析求解机器人实际作用力,最终通过控制量的计算,实现农业采摘机器人的运动协作控制功能;通过系统测试实验得出结论:所提方法控制下机器人位置、姿态角和作用力的控制误差分别为14 mm、0.2°和1.2 N,在优化设计系统控制下,机器人的碰撞次数得到明显降低。 展开更多
关键词 d-H法 农业采摘机器人 运动协作 运动控制系统
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D波段行波管电子光学系统设计
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作者 杨霄 郭祖根 +1 位作者 王鑫杨 巩华荣 《太赫兹科学与电子信息学报》 2024年第1期22-27,共6页
提出一种用于D波段行波管的电子光学系统设计方案,包括电子枪和永磁聚焦系统,并进行了验证。电子枪采用经典皮尔斯电子枪结构,阴极发射面的外层设置阴极套壳,抑制阴极边缘杂散发射;采用圆柱形控制极替代锥形控制极,同时在聚焦极加负偏压... 提出一种用于D波段行波管的电子光学系统设计方案,包括电子枪和永磁聚焦系统,并进行了验证。电子枪采用经典皮尔斯电子枪结构,阴极发射面的外层设置阴极套壳,抑制阴极边缘杂散发射;采用圆柱形控制极替代锥形控制极,同时在聚焦极加负偏压,调节电子注的压缩状态。所设计电子枪工作电压为19 kV,提供电子注电流57 mA,注腰半径为0.068 mm,射程为14.9 mm。为在半径0.15 mm的电子通道中稳定地聚焦和传输电子注,永磁聚焦系统采用周期永磁聚焦系统。峰值磁场为布里渊磁场的2.9倍,增加了电子注刚性。模拟结果显示,传输的电子注最大波动半径小于0.1 mm。按所设计的电子光学系统加工组装了试验流通短管,测试结果显示电子注电流为49.83 mA,收集极电流为49.6 mA,对应电子注流通率达到99.5%,实现了设计目标。 展开更多
关键词 d波段 电子光学系统 电子枪 磁聚焦系统 行波管
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