期刊文献+
共找到118篇文章
< 1 2 6 >
每页显示 20 50 100
A Transmission Method for the Determination of the Radiation Properties of Small Ash Particles 被引量:1
1
作者 阮立明 余其铮 谈和平 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1994年第2期10-14,共5页
The complex refractive index of small ash particles is determined from the transmittance spectrum of dilute particle suspensions obtained from experiment and by the application of the precise Mie scattering theory and... The complex refractive index of small ash particles is determined from the transmittance spectrum of dilute particle suspensions obtained from experiment and by the application of the precise Mie scattering theory and dielectric dispersion Kramers-Kroning relations. The numerical simulation results for the ash particles with data given in literature [1] show that with this method the accuracy is improved and the applicable range of the wavelength and the particle size is expanded.At last the transmittance spectrum of the ash particle cloud from Tic Fa Coal Mine was measured by an infrared spectrometer and its complex refractive index is determined. 展开更多
关键词 ss: TRANSMIssION method MIE scattering theory K-K relations SMALL PARTICLES
下载PDF
求解非厄尔米特正定线性系统的SSI-SS迭代方法
2
作者 王虹 《温州大学学报(自然科学版)》 2023年第3期20-26,共7页
基于耦合的思想,提出一个新的SSI-SS迭代法来求解非厄尔米特正定线性系统.从理论上证明了该方法的收敛性,并给出了其最优参数的选取.与SHSS-SS方法相比,该方法的迭代矩阵的谱半径上界更小.最后通过数值结果验证了该方法的数值有效性.
关键词 非厄尔米特正定 ssI-ss迭代方法 耦合 收敛速度
下载PDF
碳纤维板加固H型钢梁抗剥离夹具研制及应用试验
3
作者 周朝阳 樊文华 +1 位作者 汪毅 周锦 《工程科学学报》 EI CSCD 北大核心 2024年第3期525-535,共11页
外贴碳纤维板是钢梁抗弯加固的常用方法,但其端部易因界面应力集中导致剥离破坏,严重影响高性能材料的有效利用,特别是结构加固后的安全服役.为此开发出一种适用于H型钢梁的简易夹具——C形槽板夹,以加强碳纤维板的端部锚固.通过多根带... 外贴碳纤维板是钢梁抗弯加固的常用方法,但其端部易因界面应力集中导致剥离破坏,严重影响高性能材料的有效利用,特别是结构加固后的安全服役.为此开发出一种适用于H型钢梁的简易夹具——C形槽板夹,以加强碳纤维板的端部锚固.通过多根带夹碳纤维板加固梁的静力加载试验,验证了此夹具的可靠性,并考察了碳纤维板伸入剪跨段长度与剪跨段长度之比及锚固方式(纯粘、端锚和混锚)对加固效果的影响.研究发现端锚加固不同于纯粘,只要梁的控制截面仍在夹具之间,碳纤维板的极限应力、加固效果及利用效率均随其长度缩短而提高,当碳纤维板长度分别为600、750 mm时,前者极限应变和承载力比后者分别高27.3%和8.1%.由于钢梁表面处理质量较差,混锚加固梁均发生突然剥离,后期退化为端锚加固梁,因而相比端锚加固梁加固效果改善不大,需要提高表面处理质量再做类似研究.尽管如此,相比纯粘加固梁,混锚加固梁采用C形槽板夹后剥离破坏被延迟,抗弯性能大为改善.试验过程中还用压电阻抗法对界面剥离情况进行了检测,结果符合实际. 展开更多
关键词 碳纤维板 抗弯加固 H型钢梁 剥离 C形槽板夹 压电阻抗法
下载PDF
基于4H-SiC的低横向灵敏度压阻式加速度计设计仿真研究
4
作者 白贵文 雷程 +2 位作者 梁庭 王丙寅 赵艳栋 《仪表技术与传感器》 CSCD 北大核心 2024年第8期1-5,共5页
文中基于4H-SiC设计了一种开槽式低横向灵敏度压阻式加速度计,通过分析支撑梁位置及开槽尺寸对加速度计性能的影响确定了相关结构参数,并对该结构采用有限元方法进行了热-力耦合仿真,确定了该结构在600℃温度场中施加不同载荷时的理论... 文中基于4H-SiC设计了一种开槽式低横向灵敏度压阻式加速度计,通过分析支撑梁位置及开槽尺寸对加速度计性能的影响确定了相关结构参数,并对该结构采用有限元方法进行了热-力耦合仿真,确定了该结构在600℃温度场中施加不同载荷时的理论电压输出。研究结果表明:该结构相较于已有的双端四梁结构X轴方向的横向灵敏度由3.3%降至2.6%,Y轴方向横向灵敏度由29.9%降至1.5%,传感器芯片在600℃高温环境下输入载荷与输出电压呈线性关系,100 g载荷下的理论输出电压为3.65 mV。 展开更多
关键词 4H-SIC 低横向灵敏度 压阻式加速度计 有限元方法 热-力耦合仿真
下载PDF
熔盐法制备Co_(9)S_(8)/C锂离子电池负极材料及其性能研究
5
作者 王思毅 况知凡 +4 位作者 甘振鉴 冉燕 王石泉 刘红英 张燕青 《化肥设计》 CAS 2024年第3期6-12,21,共8页
以氯化钴为钴源,硫脲为硫源,柠檬酸为碳源,冷冻干燥后,采用熔盐法在不同的温度进行退火处理得到Co_(9)S_(8)与C的复合物CS(CS-600,CS-700,CS-800,CS-900)。系统地探讨了不同的退火温度对产物的晶体结构、形貌及电化学性能的影响。结果发... 以氯化钴为钴源,硫脲为硫源,柠檬酸为碳源,冷冻干燥后,采用熔盐法在不同的温度进行退火处理得到Co_(9)S_(8)与C的复合物CS(CS-600,CS-700,CS-800,CS-900)。系统地探讨了不同的退火温度对产物的晶体结构、形貌及电化学性能的影响。结果发现:和纯Co_(9)S_(8)样品相比,碳复合的Co_(9)S_(8)样品的循环性能与倍率性能得到了较大的提升。在煅烧温度为700℃时,所合成的样品CS-700具有最高的比容量与最好的循环性能,在100 mA·g^(-1)充放电循环100次后,放电比容量可以达到898.6 mAh·g^(-1),可作为锂离子电池负极材料的潜在选择。 展开更多
关键词 负极材料 熔盐法 Co_(9)S_(8) 碳复合 锂离子电池
下载PDF
应用分值计算法优选SS琼脂配方的研究 被引量:9
6
作者 杨更发 黄怀京 《微生物学通报》 CAS CSCD 北大核心 1999年第2期113-116,共4页
 用分值计算法对四批SS琼脂质量检测,分值均小于质控标准分值56.125。主要问题是抑制大肠杆菌(Ecoli)生长和促鼠伤寒沙门氏菌(Styphimurium),痢疾志贺氏菌(S.dysenicriae)生长的能力不...  用分值计算法对四批SS琼脂质量检测,分值均小于质控标准分值56.125。主要问题是抑制大肠杆菌(Ecoli)生长和促鼠伤寒沙门氏菌(Styphimurium),痢疾志贺氏菌(S.dysenicriae)生长的能力不够。调整SS琼脂配方中各试剂的用量进行筛选,结果表明:0.5%胆盐抑制大肠杆菌(Ecoli)能力达到分值质控要求,但对鼠伤寒沙门氏菌(Styphimurium)和痢疾志贺氏菌(S.dysenicriae)的生长同样有抑制作用。0.3%胆盐抑制大肠杆菌(Ecoli)的能力不明显。0.07%柠檬酸铁和0,15%柠檬酸钠有缓和胆盐对鼠伤寒沙门氏菌(Styphimurium)的毒性,但对痢疾志贺氏菌(Sdysenicriae)作用不明显。 展开更多
关键词 分值计算法 优选 琼脂配方 沙门氏菌 志贺氏菌
下载PDF
A Discrete-type Continuation Regularization Method and its Application 被引量:1
7
作者 韩波 游建华 刘家琦 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1995年第1期5-9,共5页
Discrete-type continuation method for solving nonlinear system of equations and Tikhonov's regularization method for solving linear ill-posed problems are combined into a stable and widely convergent one for solvi... Discrete-type continuation method for solving nonlinear system of equations and Tikhonov's regularization method for solving linear ill-posed problems are combined into a stable and widely convergent one for solving nonlinear operator equations with difficultly computed and ill-conditioned derivatives. Some results about their convergence are given The application of this method to solve the inverse problem of one-dimensional diffusion equation is demonstrated. 展开更多
关键词 ss: Discrete-type continuution method REGULARIZATION method inverse problem of differential EQUATIONS
下载PDF
Convergence of a New Adapting Runge-Kutta Method to Delay Differential Equations 被引量:1
8
作者 储钟武 邱深山 刘明珠 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第4期1-4,共4页
The adapting Runge-Kutta methods with a new interpolation procedure to delay differential equations was introduced by K.J. in't Hout in 1992[1], he proved that the numerical process, satisfies an important asympto... The adapting Runge-Kutta methods with a new interpolation procedure to delay differential equations was introduced by K.J. in't Hout in 1992[1], he proved that the numerical process, satisfies an important asymptotic stability condition. In this paper the convergence of this method under the asymptotic stability and other conditions in theorem 3 is proved. 展开更多
关键词 ss: DELAY DIFFERENTIAL equation ADAPTING RUNGE-KUTTA method ASYMPTOTIC
下载PDF
The SA Method on Large Scale Goal Programming with Independent Subsystems 被引量:1
9
作者 张杰 冯英浚 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1995年第4期9-12,共4页
TheSAMethodonLargeScaleGoalProgrammingwithIndependentSubsystemsZHANGJie;FENGYingjun张杰,冯英浚(Dept.ofMathematics... TheSAMethodonLargeScaleGoalProgrammingwithIndependentSubsystemsZHANGJie;FENGYingjun张杰,冯英浚(Dept.ofMathematics,HarbinInstituteo... 展开更多
关键词 ss: Large scale optimization SERIAL adjustment method LEXICOGRAPHIC minimum
下载PDF
基于传播算子的DS-SS信号扩频波形估计 被引量:3
10
作者 解辉 姚智刚 +2 位作者 吕萌 尹园威 史林 《电讯技术》 北大核心 2019年第5期544-548,共5页
扩频信号波形估计的本质是信号子空间估计。针对直接序列扩频(Direct Sequence Spread Spectrum,DS-SS)信号的扩频波形估计问题,提出了一种基于传播算子的估计算法。针对现有算法估计信号子空间计算量较大的不足,所提算法利用传播算子... 扩频信号波形估计的本质是信号子空间估计。针对直接序列扩频(Direct Sequence Spread Spectrum,DS-SS)信号的扩频波形估计问题,提出了一种基于传播算子的估计算法。针对现有算法估计信号子空间计算量较大的不足,所提算法利用传播算子估计信号子空间。理论分析了所提算法与现有算法的计算量和性能,并进行了仿真实验。仿真结果表明所提算法有效,且计算量远小于现有算法。 展开更多
关键词 直接序列扩频 扩频波形 传播算子 信号子空间
下载PDF
基于改进传播算子的DS-SS信号扩频序列盲估计方法 被引量:3
11
作者 解辉 马俊涛 +3 位作者 姚智刚 吕萌 史林 尹园威 《电子学报》 EI CAS CSCD 北大核心 2020年第1期9-16,共8页
本文研究了DS-SS信号的扩频序列盲估计问题,针对现有特征值分解算法失步时间估计不准和计算量大等缺点,提出一种基于改进传播算子的扩频序列盲估计算法,该算法对传统传播算子估计信号子空间的方法进行了改进,使之能够估计扩频序列,并利... 本文研究了DS-SS信号的扩频序列盲估计问题,针对现有特征值分解算法失步时间估计不准和计算量大等缺点,提出一种基于改进传播算子的扩频序列盲估计算法,该算法对传统传播算子估计信号子空间的方法进行了改进,使之能够估计扩频序列,并利用信号子空间估计信号失步时间.与基于特征值分解的方法相比,本文算法提高了失步时间的估计精度,并有效的降低了计算量.最后对算法计算量和性能进行了仿真分析和验证,结果表明本文算法有效,计算量远小于现有特征值分解算法,且估计性能在低信噪比条件下更优. 展开更多
关键词 直接序列扩频 扩频序列 传播算子 特征值 信号子空间
下载PDF
A Shortcut for Extricating System Development from Predicament-by Means of Object-oriented Methods
12
作者 潘启澍 安实 +1 位作者 王福胜 张宝祥 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第3期92-95,共4页
Three main problems in system development and the plight of the system development are analyzed and discussed. Finally a practical and formalized method-object-oriented method is proposed to extncate the system develo... Three main problems in system development and the plight of the system development are analyzed and discussed. Finally a practical and formalized method-object-oriented method is proposed to extncate the system development from the predicament. 展开更多
关键词 ss: OBJECT-ORIENTED method (o-o method) RELATIONAL SYSTEM SYSTEM developing SYSTEM design
下载PDF
A Method of Wide Convergence Region for Solving Inverse Problems of Wave Equations
13
作者 刘家琦 钱建良 韩波 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1995年第4期1-4,共4页
Based on the embedding thought, a method of wide convergence region for solving the coefficient inverse problem of wave equations in the space-time variable domain is presented. The numerical simulation shows that the... Based on the embedding thought, a method of wide convergence region for solving the coefficient inverse problem of wave equations in the space-time variable domain is presented. The numerical simulation shows that the method is feasible and effective. 展开更多
关键词 ss: INVERSE problem WAVE equation EMBEDDING method
下载PDF
Restraint on the Effect of Friction by Localization Method
14
作者 胡恒章 傅丽 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1994年第2期34-36,共3页
The characterization of friction in control systems and its restraint by localization method are analyzed. The minimum velocity and position precision of control systems with friction are obtained analytically. The co... The characterization of friction in control systems and its restraint by localization method are analyzed. The minimum velocity and position precision of control systems with friction are obtained analytically. The condition of global stability is given. 展开更多
关键词 ss: LOCALIZATION method FRICTION minimum VELOCITY position precision
下载PDF
Investigation on Instantaneous Meshing Stiffness and Profile Modification of Involute Helical Gear
15
作者 孟祥生 常山 陈谌闻 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第4期54-58,共5页
An efficient finite element model of involute helical gear is presented. A program based on compliance matrix method is developed for the calculation of instantaneous meshing stiffness, and the relationship between th... An efficient finite element model of involute helical gear is presented. A program based on compliance matrix method is developed for the calculation of instantaneous meshing stiffness, and the relationship between the rate of meshing stiffness and overlap ratio is given. On the basis of stiffness calculation, an optimization program for the optimal design of profile modification is developed according to the principle of internal point punishment function method. 展开更多
关键词 ss: Instantaneous MESHING STIFFNEss PROFILE MODIFICATION compliance matrix method internal point PUNISHMENT function method
下载PDF
Adaptive Modeling and Forecasting of Time Series by Combining the Methods of Temporal Differences with Neural Networks
16
作者 杨璐 洪家荣 黄梯云 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第1期94-98,共5页
This paper discusses the modeling method of time series with neural network. In order to improve the adaptability of direct multi-step prediction models, this paper proposes a method of combining the temporal differen... This paper discusses the modeling method of time series with neural network. In order to improve the adaptability of direct multi-step prediction models, this paper proposes a method of combining the temporal differences methods with back-propagation algorithm for updating the parameters continuously on the basis of recent data. This method can make the neural network model fit the recent characteristic of the time series as close as possible, therefore improves the prediction accuracy. We built models and made predictions for the sunspot series. The prediction results of adaptive modeling method are better than that of non-adaptive modeling methods. 展开更多
关键词 ss: NEURAL network TIME SERIES forecasting TEMPORAL DIFFERENCES methodS
下载PDF
Indirect Measurement of Torque Ripple for Permanent Magnet Brushless DC Torque Motor
17
作者 孙力 张志忠 陆永平 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第3期38-43,共6页
Torque ripple is one of the most important specification indexes of brushless DC torque motors. This paper analyzes the torque ripple of a sinusoidal-driven three-phase permanent magnet(PM) brushless DC (BLDC) torque ... Torque ripple is one of the most important specification indexes of brushless DC torque motors. This paper analyzes the torque ripple of a sinusoidal-driven three-phase permanent magnet(PM) brushless DC (BLDC) torque motor and approaches the expression of torque ripple. An indirect method using armature currents to measure torque ripple and its implementation by hardware are presented. The torque ripple of the motor is measured by the indirect and the direct methods respecively. The validity of the indirect method is demonstrated by the comparative analysis of the experimental results. 展开更多
关键词 ss: BLDC TORQUE MOTOR TORQUE RIPPLE indirect sensing method
下载PDF
Residual Value Balance Method for Large Flexible Rotors
18
作者 刘荣强 武新华 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第2期74-77,共4页
A Large balancing weight may be obtained by calculation, when the ordinary influence coefficient method is used. In this paper, a new residual value balance method is recommended. The fundamental idea of the new metho... A Large balancing weight may be obtained by calculation, when the ordinary influence coefficient method is used. In this paper, a new residual value balance method is recommended. The fundamental idea of the new method is on the principle of getting the minimized weight on condition that the vibration values at various points are less than the admitted ones. Experimental results show that this method is effective for balancing the insensitive rotor and rotors with special dynamic characteristics. 展开更多
关键词 ss:Flexible rotors balancing method INFLUENCE COEFFICIENT
下载PDF
The Stability of Runge-Kutta Methods for Systems of Delay Differential Equations
19
作者 王晓彪 刘明珠 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第1期1-6,共6页
TheStabilityofRunge-KuttaMethodsforSystemsofDelayDifferentialEquations¥WANGXiaobiao;LIUMingzhu(王晓彪)(刘明珠)(Dept.... TheStabilityofRunge-KuttaMethodsforSystemsofDelayDifferentialEquations¥WANGXiaobiao;LIUMingzhu(王晓彪)(刘明珠)(Dept.ofMathematics,Har... 展开更多
关键词 ss:Delay DIFFERENTIAL EQUATIONS numerical solution RUNGE-KUTTA methodS STABILITY
下载PDF
A Differential Continuation-Regularization Method for Solving Inverse Problems of Acoustic Wave Equations
20
作者 张大力 韩波 +1 位作者 刘家琦 姜立功 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1995年第1期10-14,共5页
ADifferentialContinuation-RegularizationMethodforSolvingInverseProblemsofAcousticWaveEquations¥(张大力)(韩波)(刘家琦... ADifferentialContinuation-RegularizationMethodforSolvingInverseProblemsofAcousticWaveEquations¥(张大力)(韩波)(刘家琦)(姜立功)ZHANGDali;H... 展开更多
关键词 ss:Inverse problems geophysical prospecting DIFFERENTIAL CONTINUATION method ACOUSTIC WAVE equation REGULARIZATION
下载PDF
上一页 1 2 6 下一页 到第
使用帮助 返回顶部