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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS KLEIN GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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Efficient rock joint detection from large-scale 3D point clouds using vectorization and parallel computing approaches
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作者 Yunfeng Ge Zihao Li +2 位作者 Huiming Tang Qian Chen Zhongxu Wen 《Geoscience Frontiers》 2025年第5期1-15,共15页
The application of three-dimensional(3D)point cloud parametric analyses on exposed rock surfaces,enabled by Light Detection and Ranging(LiDAR)technology,has gained significant popularity due to its efficiency and the ... The application of three-dimensional(3D)point cloud parametric analyses on exposed rock surfaces,enabled by Light Detection and Ranging(LiDAR)technology,has gained significant popularity due to its efficiency and the high quality of data it provides.However,as research extends to address more regional and complex geological challenges,the demand for algorithms that are both robust and highly efficient in processing large datasets continues to grow.This study proposes an advanced rock joint identification algorithm leveraging artificial neural networks(ANNs),incorporating parallel computing and vectorization of high-performance computing.The algorithm utilizes point cloud attributes—specifically point normal and point curvatures-as input parameters for ANNs,which classify data into rock joints and non-rock joints.Subsequently,individual rock joints are extracted using the density-based spatial clustering of applications with noise(DBSCAN)technique.Principal component analysis(PCA)is subsequently employed to calculate their orientations.By fully utilizing the computational power of parallel computing and vectorization,the algorithm increases the running speed by 3–4 times,enabling the processing of large-scale datasets within seconds.This breakthrough maximizes computational efficiency while maintaining high accuracy(compared with manual measurement,the deviation of the automatic measurement is within 2°),making it an effective solution for large-scale rock joint detection challenges.©2025 China University of Geosciences(Beijing)and Peking University. 展开更多
关键词 Rock joints Pointclouds Artificialneuralnetwork High-performance computing Parallel computing vectorization
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Gene editing for corneal disease management
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作者 Sudhanshu P Raikwar Apoorva S Raikwar +1 位作者 Shyam S Chaurasia Rajiv R Mohan 《World Journal of Translational Medicine》 2016年第1期1-13,共13页
Gene editing has recently emerged as a promising technology to engineer genetic modifications precisely in the genome to achieve long-term relief from corneal disorders.Recent advances in the molecular biology leading... Gene editing has recently emerged as a promising technology to engineer genetic modifications precisely in the genome to achieve long-term relief from corneal disorders.Recent advances in the molecular biology leading to the development of clustered regularly interspaced short palindromic repeats(CRISPRs) and CRISPR-associated systems,zinc finger nucleases and transcription activator like effector nucleases have ushered in a new era for high throughput in vitro and in vivo genome engineering.Genome editing can be successfully used to decipher complex molecular mechanisms underlying disease pathophysiology,develop innovative next generation gene therapy,stem cell-based regenerative therapy,and personalized medicine for corneal and other ocular diseases.In this review we describe latest developments in the field of genome editing,current challenges,and future prospects for the development of personalized genebased medicine for corneal diseases.The gene editing approach is expected to revolutionize current diagnostic and treatment practices for curing blindness. 展开更多
关键词 ADENO-ASSOCIATED virus Clustered Regularly-Interspaced SHORT Palindromic Repeats associated protein 9 Cornea Clustered regularly interspaced SHORT palindromic repeat Double strand breaks GENE EDITING sgRNA GENE targeting Homology directed repair Homologous recombination INDELS Lentiviral vector Protospacer-adjacent motif Transcription activator like effector NUCLEASES Zinc finger NUCLEASES
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基于遗传算法和最小二乘支持向量机的织物剪切性能预测 被引量:2
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作者 卢桂馥 王勇 +1 位作者 窦易文 Gui-fu Yi-wen 《计量学报》 CSCD 北大核心 2009年第6期-,共4页
提出了一种基于最小二乘支持向量机的织物剪切性能预测模型,并且采用遗传算法进行最小二乘支持向量机的参数优化,将获得的样本进行归一化处理后,将其输入预测模型以得到预测结果.仿真结果表明,基于最小二乘支持向量机的预测模型比BP神... 提出了一种基于最小二乘支持向量机的织物剪切性能预测模型,并且采用遗传算法进行最小二乘支持向量机的参数优化,将获得的样本进行归一化处理后,将其输入预测模型以得到预测结果.仿真结果表明,基于最小二乘支持向量机的预测模型比BP神经网络和线性回归方法具有更高的精度和范化能力. Abstract: A new method is proposed to predict the fabric shearing property with least square support vector machines ( LS-SVM ). The genetic algorithm is investigated to select the parameters of LS-SVM models as a means of improving the LS- SVM prediction. After normalizing the sampling data, the sampling data are inputted into the model to gain the prediction result. The simulation results show the prediction model gives better forecasting accuracy and generalization ability than BP neural network and linear regression method. 展开更多
关键词 SUPPORT VECTOR MACHINES sampling data SUPPORT VECTOR MACHINES generalization ability simulation results linear regression genetic algorithm BP neural network prediction model 线 LS-SVM least square new method
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生长激素信号肽可诱导重组蛋白外分泌表达 被引量:4
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作者 张志谦 李金萍 胡颖 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2005年第2期282-286,共5页
Signal peptide capable of efficiently directing many protein secretion in mammalian cells is one of the key elements in recombinant protein production,gene therapy and the development of DNA vaccines.In order to explo... Signal peptide capable of efficiently directing many protein secretion in mammalian cells is one of the key elements in recombinant protein production,gene therapy and the development of DNA vaccines.In order to explore the possibility of rat growth hormone signal peptide as such an element,a new vector based on the mammalian expression vector pcDNA3 was constructed by employing rat growth hormone(rGH) signal peptide as leading sequence,followed by multiple cloning sites,the myc epitope-tag and 6×his purification tag in the expression cassette.The vector was validated by successfully expressing and secretion of chick MMP-2 C-terminal PEX domain,a potential angiogenesis inhibitor,and tandem peptide repeats of myc epitope-tag in COS-7 cells.These results suggest that rat growth hormone signal peptide is effective in the mediation of recombinant protein expression and secretion,and this vector provides a new tool for universal cloning and secretion of exogenous proteins in mammalian cells. 展开更多
关键词 expression vector SIGNAL universal elements multiple SIGNAL PCDNA3 domain the and MMP-2 COS-7 rat tool new was one key his tag The PEX for ce
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Overexpression of heme oxygenase-1 protects smooth muscle cells against oxidative injury and inhibits cell proliferation 被引量:17
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作者 MIN ZHANG, BAO HuI ZHANG, LI CHEN, WEI AN1 Institute of Sports Medicine, The Third Hospital, Peking University, Beijing 100083, China 2Department of Cell Biology, Capital University of Medical Sciences, Beijing 100054, China 《Cell Research》 SCIE CAS CSCD 2002年第2期123-132,共10页
To investigate whether the expression of exogenous heme oxygenase-1 (HO-1) gene within vascular smooth muscle cells (VSMC) could protect the cells from free radical attack and inhibit cell proliferation, we establishe... To investigate whether the expression of exogenous heme oxygenase-1 (HO-1) gene within vascular smooth muscle cells (VSMC) could protect the cells from free radical attack and inhibit cell proliferation, we established an in vitro transfection of human HO-1 gene into rat VSMC mediated by a retroviral vector. The results showed that the profound expression of HO-1 protein as well as HO activity was 1.8- and 2.0-fold increased respectively in the transfected cells compared to the non-transfected ones. The treatment of VSMC with different concentrations of H2O2 led to the remarkable cell damage as indicated by survival rate and LDH leakage. However, the resistance of the HO-1 transfected VSMC against H2O2 was significantly raised. This protective effect was dramatically diminished when the transfected VSMC were pretreated with ZnPP-IX, a specific inhibitor of HO, for 24 h. In addition, we found that the growth potential of the transfected cells was significantly inhibited directly by increased activity of HO-1, and this effect might be related to decreased phosphorylation of MAPK. These results suggest that the overexpression of introduced hHO-1 is potentially able to reduce the risk factors of atherosclerosis, partially due to its cellular protection against oxidative injury and to its inhibitory effect on cellular proliferation. 展开更多
关键词 Animals Blotting Northern Blotting Southern Blotting Western Cell Division Cell Survival Cells Cultured Cyclic GMP Dose-Response Relationship Drug Flow Cytometry Free Radicals Genetic Vectors Heme Oxygenase (Decyclizing) Heme Oxygenase-1 Humans Hydrogen Peroxide MAP Kinase Signaling System Male Membrane Proteins Muscle Smooth Myocytes Smooth Muscle OXIDANTS Oxidative Stress Oxygen Phosphorylation RATS Rats Sprague-Dawley Research Support Non-U.S. Gov't RETROVIRIDAE Time Factors Transfection
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New Evidence, Conditions, Instruments &Experiments for Gravitational Theories
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作者 Benjamin T. Solomon 《Journal of Modern Physics》 2013年第8期183-196,共14页
Two significant findings compel a rethink of physical theories. First, using a 7-billion-year-old gamma-ray burst, Nemiroff (2012) showed that quantum foam could not exists. And second, Solomon (2011) showed that grav... Two significant findings compel a rethink of physical theories. First, using a 7-billion-year-old gamma-ray burst, Nemiroff (2012) showed that quantum foam could not exists. And second, Solomon (2011) showed that gravitational acceleration is not associated with the gravitating mass, that gravitational acceleration g is determined solely by τ the change in time dilation over a specific height multiplied by c2 or g = τc2. Seeking consistency with Special Theory of Relativity, as means to initiate this rethink, this paper examines 12 inconsistencies in physical theories that manifest from empirical data. The purpose of this examination is to identify how gravitational theories need to change or be explored, to eliminate these 12 inconsistencies. It is then proposed that spacetime is much more sophisticated than just a 4-dimensional continuum. And, that the Universe consists of at least two layers or “kenos” (Greek for vacuous), the 4-dimensional kenos, spacetime (x, y, z, t) and the 3-dimensional kenos, subspace (x, y, z) that are joined at the space coordinates (x, y, z). This explains why electromagnetic waves are transverse, and how probabilities are implemented in Nature. This paper concludes by proposing two new instruments and one test, to facilitate research into gravitational fields, the new torsion-, tension- and stress-free near field gravity probe, the gravity wave telescope, and a non-locality test. 展开更多
关键词 RELATIVITY Special THEORY of RELATIVITY General THEORY of RELATIVITY Entanglement Baking Bread Transverse WAVE Electromagnetism Separation Vectors Gamma Ray Burst Quarks GRAVITY Modification Exotic Matter Photons Strings Shielding CLOAKING INVISIBILITY Near Field GRAVITY Probe WAVE Function Gaussian
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基于提升小波和LS-SVM的大坝变形预测 被引量:7
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作者 秦栋 郑雪琴 许后磊 《水电能源科学》 北大核心 2010年第9期64-66,共3页
提出了一种基于提升小波和最小二乘支持向量机的大坝变形预测方法,通过提升小波分析提取大坝监测数据效应量,分别对各效应量使用最小二乘支持向量机模型进行训练预测,再将合成各分量的预测结果作为最终的变形预测结果。算例结果表明,该... 提出了一种基于提升小波和最小二乘支持向量机的大坝变形预测方法,通过提升小波分析提取大坝监测数据效应量,分别对各效应量使用最小二乘支持向量机模型进行训练预测,再将合成各分量的预测结果作为最终的变形预测结果。算例结果表明,该方法较符合实际情况,具有很高的预测精度和良好的泛化能力。 展开更多
关键词 LS-SVM Support Vector Machine Least Square LIFTING Wavelet Based
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基于鲁棒LS-SVM的控制图模式识别 被引量:1
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作者 程志强 马义中 Zhi-qiang Yi-zhong 《计量学报》 CSCD 北大核心 2009年第6期-,共3页
提出一种基于鲁棒最小二乘支持向量机(LS-SVM)的控制图模式识别方法,并研究其应用于过程质量诊断的可行性、有效性.理论研究和仿真试验结果表明,该方法对于标准的6种控制图模式都具有很高的模式识别率,训练模式识别器所需样本少,且训练... 提出一种基于鲁棒最小二乘支持向量机(LS-SVM)的控制图模式识别方法,并研究其应用于过程质量诊断的可行性、有效性.理论研究和仿真试验结果表明,该方法对于标准的6种控制图模式都具有很高的模式识别率,训练模式识别器所需样本少,且训练结果泛化能力强,计算方法简单迅速. Abstract: A technique based on the robust least squares support vector machines(LS-SVM) used for control charts pattern recognition is proposed, the applied feasibility and validity of this technique in process quality diagnosis is also investigated. Theoretical research and experimental results show that this approach performs well upon the six typical control charts pattern recognition with high recognition accuracy, simple computation and fast training process, and the preeminent generalization ability on the condition of small sample size. 展开更多
关键词 LS-SVM Robust Based PATTERN RECOGNITION PATTERN RECOGNITION control charts support vector machines generalization ability Theoretical research training PROCESS PROCESS quality least SQUARES small sample
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大豆抗病相关基因SR1正反义植物表达载体的构建及遗传转化研究 被引量:3
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作者 林世锋 张淑珍 +3 位作者 杨秀红 陈庆山 杨庆凯 李文滨 《大豆科学》 CAS CSCD 北大核心 2005年第2期90-94,共5页
实验构建了CaMV35S启动子控制下的大豆抗病相关基因SR1的正反义植物双元表达载体pBISR1(+)和pBISR1(-)。通过根癌农杆菌叶盘转化法,将正义和反义SR1 基因导入烟草Ha vana 425,经卡那霉素筛选,获得了抗性植株。经PCR和PCR-Southern印迹分... 实验构建了CaMV35S启动子控制下的大豆抗病相关基因SR1的正反义植物双元表达载体pBISR1(+)和pBISR1(-)。通过根癌农杆菌叶盘转化法,将正义和反义SR1 基因导入烟草Ha vana 425,经卡那霉素筛选,获得了抗性植株。经PCR和PCR-Southern印迹分析,证明抗性植株中整和了SR1基因,RT-PCR分析进一步表明正义和反义基因皆能转录为完整的mRNA,经疫霉根腐接种及抗病性鉴定表明,转反义基因株系和未转基因株系均轻微感病,而转正义基因株系始终没有出现感病症状。 展开更多
关键词 35S PCR CaMV mRNA
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Adaptive Fuzzy Sliding Mode Controller for Grid Interface Ocean Wave Energy Conversion
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作者 Adel A. A. Elgammal 《Journal of Intelligent Learning Systems and Applications》 2014年第2期53-69,共17页
This paper presents a closed-loop vector control structure based on adaptive Fuzzy Logic Sliding Mode Controller (FL-SMC) for a grid-connected Wave Energy Conversion System (WECS) driven Self-Excited Induction Generat... This paper presents a closed-loop vector control structure based on adaptive Fuzzy Logic Sliding Mode Controller (FL-SMC) for a grid-connected Wave Energy Conversion System (WECS) driven Self-Excited Induction Generator (SEIG). The aim of the developed control method is to automatically tune and optimize the scaling factors and the membership functions of the Fuzzy Logic Controllers (FLC) using Multi-Objective Genetic Algorithms (MOGA) and Multi-Objective Particle Swarm Optimization (MOPSO). Two Pulse Width Modulated voltage source PWM converters with a carrier-based Sinusoidal PWM modulation for both Generator- and Grid-side converters have been connected back to back between the generator terminals and utility grid via common DC link. The indirect vector control scheme is implemented to maintain balance between generated power and power supplied to the grid and maintain the terminal voltage of the generator and the DC bus voltage constant for variable rotor speed and load. Simulation study has been carried out using the MATLAB/Simulink environment to verify the robustness of the power electronics converters and the effectiveness of proposed control method under steady state and transient conditions and also machine parameters mismatches. The proposed control scheme has improved the voltage regulation and the transient performance of the wave energy scheme over a wide range of operating conditions. 展开更多
关键词 GRID integration Wave Energy Conversion Systems Self-Excited Induction Generator (SEIG) Vector CONTROL Genetic Algorithm (GA) Particle SWARM Optimization (PSO) SLIDING Mode CONTROL (SMC) Fuzzy Logic CONTROL (FLC) MEMBERSHIP Function Tuning
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STUB1基因RNA干扰慢病毒载体的构建与鉴定 被引量:3
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作者 赵虹 张惊宇 +2 位作者 徐万海 杨子超 赵庆杰 《浙江大学学报(医学版)》 CAS CSCD 北大核心 2010年第6期623-627,共5页
目的:构建人STUB1基因RNA干扰(RNA interference,RNAi)慢病毒表达载体并进行鉴定。方法:针对筛选确定的人STUB1基因RNAi有效靶点序列,合成靶序列的Oligo DNA,退火形成双链DNA,与经AgeI和EcoRI酶切后的pMagic 4.0载体连接,产生短发卡RNA... 目的:构建人STUB1基因RNA干扰(RNA interference,RNAi)慢病毒表达载体并进行鉴定。方法:针对筛选确定的人STUB1基因RNAi有效靶点序列,合成靶序列的Oligo DNA,退火形成双链DNA,与经AgeI和EcoRI酶切后的pMagic 4.0载体连接,产生短发卡RNA慢病毒载体。PCR筛选阳性克隆,测序鉴定,并包装成慢病毒颗粒。结果:PCR鉴定与DNA测序证实,合成的含STUB1 shRNA慢病毒载体寡核苷酸链插入正确。STUB1 shRNA慢病毒载体在293T细胞中成功包装成慢病毒颗粒。结论:成功构建人STUB1基因RNAi慢病毒载体以及包装成功慢病毒颗粒,为研究STUB1在胶质瘤发生发展过程中相关信号通路的作用,提供了稳定感染细胞的载体。 展开更多
关键词 RNA RNA interference LENTIVIRAL vector RNAi shRNA DNA
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人自噬基因hAPG_(12)的克隆及其重组真核表达载体的构建 被引量:1
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作者 何才姑 郑文岭 +1 位作者 朴英杰 胡莲美 《陕西医学杂志》 CAS 北大核心 2005年第4期387-389,411,F004,共5页
目的:探讨克隆人自噬基因h APG12 ,构建重组真核表达载体p EGFP- C2 -h APG12 ,为进一步研究h APG12 的功能奠定基础。方法:从正常人外周血单个核细胞中提取总RNA,采用两步法RT- PCR,首先把RNA逆转录为c DNA,而后通过一对h APG12 的特... 目的:探讨克隆人自噬基因h APG12 ,构建重组真核表达载体p EGFP- C2 -h APG12 ,为进一步研究h APG12 的功能奠定基础。方法:从正常人外周血单个核细胞中提取总RNA,采用两步法RT- PCR,首先把RNA逆转录为c DNA,而后通过一对h APG12 的特异性引物扩增出目的基因,PCR产物与测序载体p UC18连接后转化到大肠杆菌DH5 α,而后对单菌落进行菌落PCR、酶切和测序鉴定。将测序正确的h APG12 亚克隆入真核表达载体p EGFP-C2 ,该重组载体转化到大肠杆菌DH5 α后进行菌落PCR和酶切鉴定。结果:测序结果表明从正常人外周血单个核细胞中所获得的h APG12 c DNAs含有2 2 5个碱基,与Genbank( BC0 1 1 0 33)序列完全一致。构建的重组真核表达载体经鉴定证实h APG12 基因已完全正确亚克隆到p EGFP- C2 。结论:成功克隆了人自噬基因h APG12 并构建了具有报告基因-增强绿色荧光蛋白( EGFP)基因的重组真核表达载体p EGFP- C2 - h APG12 ,为以后研究h APG12 展开更多
关键词 绿 RT-PCR DH5Α PUC18 PCR RNA cDNA
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乙型肝炎病毒S基因与截短C基因融合的穿梭表达载体的构建
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作者 胡兴斌 徐志凯 +5 位作者 尹文 韦三华 雷迎锋 杨敬 吕欣 孙梦宁 《生物技术通讯》 CAS 2005年第3期259-261,共3页
研究目的是构建HBVS基因和截短C基因融合的胞壁型和分泌型大肠杆菌和分枝杆菌(E.coli-BCG)穿梭质粒。采用PCR方法从结核分枝杆菌MTB毒株H37Rv的基因中扩增出相对分子质量为19000的抗原胞壁区及其上游调控元件基因,克隆入穿梭载体pOLYG... 研究目的是构建HBVS基因和截短C基因融合的胞壁型和分泌型大肠杆菌和分枝杆菌(E.coli-BCG)穿梭质粒。采用PCR方法从结核分枝杆菌MTB毒株H37Rv的基因中扩增出相对分子质量为19000的抗原胞壁区及其上游调控元件基因,克隆入穿梭载体pOLYG中。以含HBV基因组的质粒pCP10序列为模板,PCR扩增获得S基因片段Sw和C基因编码氨基端的部分基因片段Ct,克隆入胞壁型穿梭表达载体pCW和分泌型穿梭表达载体pDE22。经酶切和序列测定证实,胞壁型和分泌型载体pCW-Sw-Ct和pDE22-Sw-Ct构建成功。为进一步研究含S基因和截短C基因融合的重组BCG活疫苗奠定了基础。 展开更多
关键词 S PCR PCR 穿 穿 HBV MTB BCG
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Resource Efficient Hardware Implementation for Real-Time Traffic Sign Recognition
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作者 Huai-Mao Weng Ching-Te Chiu 《Journal of Transportation Technologies》 2018年第3期209-231,共23页
Traffic sign recognition (TSR, or Road Sign Recognition, RSR) is one of the Advanced Driver Assistance System (ADAS) devices in modern cars. To concern the most important issues, which are real-time and resource effic... Traffic sign recognition (TSR, or Road Sign Recognition, RSR) is one of the Advanced Driver Assistance System (ADAS) devices in modern cars. To concern the most important issues, which are real-time and resource efficiency, we propose a high efficiency hardware implementation for TSR. We divide the TSR procedure into two stages, detection and recognition. In the detection stage, under the assumption that most German traffic signs have red or blue colors with circle, triangle or rectangle shapes, we use Normalized RGB color transform and Single-Pass Connected Component Labeling (CCL) to find the potential traffic signs efficiently. For Single-Pass CCL, our contribution is to eliminate the “merge-stack” operations by recording connected relations of region in the scan phase and updating the labels in the iterating phase. In the recognition stage, the Histogram of Oriented Gradient (HOG) is used to generate the descriptor of the signs, and we classify the signs with Support Vector Machine (SVM). In the HOG module, we analyze the required minimum bits under different recognition rate. The proposed method achieves 96.61% detection rate and 90.85% recognition rate while testing with the GTSDB dataset. Our hardware implementation reduces the storage of CCL and simplifies the HOG computation. Main CCL storage size is reduced by 20% comparing to the most advanced design under typical condition. By using TSMC 90 nm technology, the proposed design operates at 105 MHz clock rate and processes in 135 fps with the image size of 1360 × 800. The chip size is about 1 mm2 and the power consumption is close to 8 mW. Therefore, this work is resource efficient and achieves real-time requirement. 展开更多
关键词 TRAFFIC SIGN Recognition Advanced Driver ASSISTANCE System REAL-TIME Processing Color Segmentation Connected Component Analysis Histo-gram of Oriented Gradient Support Vector Machine German TRAFFIC SIGN Detection BENCHMARK CMOS ASIC VLSI
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广东潮州某部登革热、流行性乙型脑炎的监测及综合防制研究 被引量:4
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作者 林立辉 文艺 +5 位作者 李萌 刘建伟 李云 白志军 陈唯军 方美玉 《中国媒介生物学及控制杂志》 CAS CSCD 北大核心 2005年第2期124-126,共3页
目的探索潮州某驻军登革热和流行性乙型脑炎(乙脑)等虫媒病综合防制效果,为预防和控制虫媒病毒病提供科学依据。方法收集发热可疑患者和健康人血标本及蚊虫标本作病毒分离和血清学抗体调查;按全面或随机法调查营区内蚊虫孳生情况,人诱... 目的探索潮州某驻军登革热和流行性乙型脑炎(乙脑)等虫媒病综合防制效果,为预防和控制虫媒病毒病提供科学依据。方法收集发热可疑患者和健康人血标本及蚊虫标本作病毒分离和血清学抗体调查;按全面或随机法调查营区内蚊虫孳生情况,人诱法监测成蚊叮刺率;用C6/36细胞培养法分离病毒并用间接免疫荧光法(IFAT)或逆转录聚合酶链反应(RT PCR)法鉴定;用IFAT调查健康人群登革热和乙脑抗体;以“治本清源”为原则,普及防病知识和开展爱国卫生运动,针对不同孳生地类型和栖息特点采用不同方法处理。结果经监测发热待查病人和媒介蚊虫均未分离出病毒;健康人群登革热和乙脑的抗体水平不高;处理前蚊类优势种为白纹伊蚊和致倦库蚊,有少量三带喙库蚊和骚扰阿蚊,其中白纹伊蚊的容器指数(CI)为24.1,百户指数(BI)为30.0,均高于规定的危险地区界限20.0。结论该驻地存在登革热和乙脑暴发流行潜在危险,蚊虫密度较高,人群抗体水平低,采用综合防制措施后,经3年连续观察,蚊媒已控制在不足为害的水平。 展开更多
关键词 广 IFAT
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基于单矢量水听器弱信号值班检测系统 被引量:2
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作者 王德俊 惠俊英 +2 位作者 蔡平 樊世斌 苏龙滨 《声学技术》 EI CSCD 北大核心 2005年第1期1-3,25,共4页
采用平均声强作为检测量,设计出一种基于单个矢量水听器的低功耗弱信号值班检测系统。针对矢量信号特有的 90°相移、指向性零点、相乘再积分、正负双极性等问题,设计了宽带全通 90°移相网络、双通道检测、1Bit模数混合乘法器... 采用平均声强作为检测量,设计出一种基于单个矢量水听器的低功耗弱信号值班检测系统。针对矢量信号特有的 90°相移、指向性零点、相乘再积分、正负双极性等问题,设计了宽带全通 90°移相网络、双通道检测、1Bit模数混合乘法器、定时放电、绝对值检测等功能电路。系统设计中兼顾高增益、低功耗、稳定可靠等实际需要,并选用微功耗模拟器件。系统仿真研究显示,该系统作用距离超过 2km。初步设计制作的实验电路板,工作带宽达到1. 8kHz,工作电流 5mA,稳定可靠。 展开更多
关键词 90° 仿
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五相逆变器的空间矢量PWM控制 被引量:57
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作者 于飞 张晓锋 +1 位作者 李槐树 宋庆国 《中国电机工程学报》 EI CSCD 北大核心 2005年第9期40-46,共7页
多相逆变器由于电压矢量的增加,其空间矢量PWM(SVPWM)控制同三相电机相比具有更大的灵活性,文中通过对五相逆变器电压矢量空间的分析,认为多相逆变器空间矢量PWM 控制的线性调制范围及形成的电机定子磁通要优于三相电机。根据五相逆变... 多相逆变器由于电压矢量的增加,其空间矢量PWM(SVPWM)控制同三相电机相比具有更大的灵活性,文中通过对五相逆变器电压矢量空间的分析,认为多相逆变器空间矢量PWM 控制的线性调制范围及形成的电机定子磁通要优于三相电机。根据五相逆变器的结构特点,在传统的最近两矢量SVPWM(NTV-SVPWM)控制的基础上,提出了两种新的五相逆变器SVPWM 控制方式:最近四矢量SVPWM(NFV-SVPWM) 控制和最小开关损耗SVPWM(MSL-SVPWM)控制。推导了3 种控制方式下的目标输出电压函数及波形,通过对比分析,认为:NTV-SVPWM控制含有较大的低次谐波,不适宜用于多相控制;NFV-SVPWM 控制的输出谐波最小,MSL-SVPWM 控制的开关损耗最小,分别适用于低调制指数和高调制指数工作区。利用MATLAB 对五相同步电机调速控制系统进行了仿真研究,仿真结果验证了上述结论。 展开更多
关键词 PWM SVPWM PWM MATLAB 线 仿 仿
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量子力学角动量理论之缺陷与修正 被引量:1
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作者 汪克林 曹则贤 《物理》 北大核心 2025年第5期344-351,共8页
角动量理论是量子力学的重要内容。基于角动量分量同三维转动生成元具有同样的基本对易关系的考量,则由基本对易关系就得到了分立的本征值谱(J^(2),J_(z))~(j(j+1),m)。又由于球坐标系下角动量平方J^(2)与动能算符的角部分相同,角动量... 角动量理论是量子力学的重要内容。基于角动量分量同三维转动生成元具有同样的基本对易关系的考量,则由基本对易关系就得到了分立的本征值谱(J^(2),J_(z))~(j(j+1),m)。又由于球坐标系下角动量平方J^(2)与动能算符的角部分相同,角动量就这样被纳入了波力学方程,由此解得的定态波函数是(H,J^(2),J_(z))的共同本征函数。然而,不同于波函数理论体系,在后来发展的算符—态矢理论体系中,态矢携带关于系统的全部信息。将角动量用必要的三组独立产生—湮灭算符表示,并在算符—态矢理论体系中考察角动量算符,会发现定态不必然还是(H,J^(2),J_(z))的共同本征态。以在球坐标系和直角坐标系下皆可分离变量的严格可解三维各向同性谐振子为依据,作者详细研究了定态对应的态矢子空间中的(H,J^(2),J_(z))本征值谱问题。在给定总粒子数n的情形下,即限制在特定的n所决定的子空间中,算符—态矢表示给出的角动量分量J_(z)具有分立的本征值而角动量的本征值却可以是连续变化的,而这正反映出角动量算符J=x×p的根本性质。当角动量分量本征值(以ℏ为单位)接近总粒子数n时,基于态矢的计算与基于波函数的计算其结果是一致的,原因是n一定的定态被限制在态矢空间中的一个由等能面所定义的子空间中了。认识到既有的量子力学角动量理论的一些缺陷,则此前涉及轨道角动量之物理效应的相关表述都有修正的必要。 展开更多
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数据挖掘方法用于中药水提液膜过程优化的研究 被引量:18
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作者 郭立玮 董洁 +3 位作者 樊文玲 陆文聪 刘亮 陈念贻 《世界科学技术-中医药现代化》 2005年第3期42-47,共6页
用数据挖掘技术研究常见的7种中药水提液体系中淀粉、果胶等高分子物质组成、物理化学性质与Al2O3陶瓷膜膜通量之间的关系。结果发现本实验体系:(1)中药水提液的粘度、粒径分布(D50)分别与有关变量呈近线性关系,且果胶含量对粘度、粒径... 用数据挖掘技术研究常见的7种中药水提液体系中淀粉、果胶等高分子物质组成、物理化学性质与Al2O3陶瓷膜膜通量之间的关系。结果发现本实验体系:(1)中药水提液的粘度、粒径分布(D50)分别与有关变量呈近线性关系,且果胶含量对粘度、粒径分布(D50)的影响较大;(2)中药水提液的pH值与X1(固含物)、X3(果胶)等变量没有简单的线性关系,但采用模式识别方法,可以找到pH值的定性规律;(3)初步认识到中药水提液这一复杂体系影响Al2O3陶瓷微滤膜膜通量的主要因素,即水提液中的蛋白质含量、原液pH值和粒径分布(D50);(4)利用自行开发的数据挖掘软件处理有关数据,得到膜通量下降速率与原液中粒径分布参数、pH值之间的定量关系,“留一法交叉验证”表明该定量关系的预报结果正确,基本锁定了造成该体系通量衰减的主要因素,使得中药水提液膜过程优化设计取得突破性进展。 展开更多
关键词 Al2O3 线 pH
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