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燕山大学学报

燕山大学学报

北大核心

CSTPCD

Journal of Yanshan University
本刊是由燕山大学主办的自然科学学术性刊物，季刊，国内外公开发行。它以繁荣科学文化、促进学术交流、发现培养人才、为两个文明建设服务为办刊宗旨。主要刊登学术论文。
  • 发文量：2214
  • 被引量：530
  • H指数：1
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  • 国内刊号/CN：13-1219/N
    国际刊号/ISSN：1007-791X
  • 发行周期：双月刊
    邮发代号：18-73
  • 主管单位：河北省教育厅
    主办单位：燕山大学
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  • 主编：胡春海
  • 电话：0335-8057043
  • 邮箱：xuebao@ysu.edu.cn
  • 地址：河北省秦皇岛市河北大街西段438号
  • 邮编：066004
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燕山大学学报 >2023年第6期

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  • 摘要：A novel 3-UPS 6-DOF parallel mechanism with three branches is designed and its inverse kinematics is built. By giving the main constraint, the boundary and the section of constant orientation workspace are described using 3D polar boundary search method. The effects of parameters on the workspace volume are analyzed for the parameter selection. This mechanism has a large workspace and good at continuity. It is suitable for legs of robot.%设计了一种新型3分支6自由度3-UPS并联机构，建立了该机构的运动学反解模型，给出机构主要约束，应用三维极坐标边界搜索方法绘制出在定姿态工作空间截面图和边界三维实体图，分析了机构参数对工作空间体积大小的影响规律，为机构参数的选取提供了依据。该并联机构工作空间大、连续性好，适合作为机器人步行器的腿结构。
  • 摘要：To overcome the serious influence of synchronization offset on OFDM systems, a joint timing and frequency synchronization algorithm for OFDM based on a new structure of training sequence is proposed. The performance of the proposed scheme is presented in terms of mean and mean-square error (MSE) obtained by simulations. The theoretical analysis and simulation results show that the proposed scheme eliminates the ambiguity which occurs in Schmidl algorithm, so it has better synchronization precision. Furthermore, the integer frequency offset can be obtained in time domain, that will reduce the computation complexity.%针对正交频分复用OFDM系统对时间同步和频率同步的敏感性，设计出一种新的训练序列，基于这种新的训练序列给出了联合时频同步算法。通过仿真对本文算法和Schmidl定时算法的均值和方差进行了比较，理论分析和仿真结果表明，本文算法消除了Schmidl算法的定时平台现象，具有更好的同步精度，整数频偏估计在时域进行，降低了运算量。
  • 摘要：为了给工程应用中提供更多的最佳离散信号,在研究差集偶性质的基础上,本文将并行计算的思想和差集偶的乘子定理引入了差集偶的搜索中,并将差集偶的搜索范围扩大到200以上,为寻找差集偶的构造方法提供了必要的前提.%For providing the more perfect discrete signal for engineering applications, the ideas of parallel computing and multiplier theorems of difference set pairs to search different set pairs are introduced, and the range extended to 200 and above. Even the necessary precondition for the search of difference set pairs construction method is provided.
  • 摘要：确定抽油机井合理流压是采油工程与油藏工程的重要研究内容.本文建立了以系统效率最高为评价指标的抽油机井合理流压仿真方法,具体包括:基于抽油机井井筒油气水多相稳定流动的泵排出口压力与油井产液量的耦合仿真模型；有效功率的仿真计算方法；基于抽油杆柱轴向振动与悬点示功图仿真的电动机输入功率仿真模型:系统效率与流压、油藏参数、抽汲参数之间函数关系的仿真模型；给定流压条件下系统效率极值的仿真模型:系统效率极值随流压的变化规律以及合理流压的确定方法.仿真分析结果表明:流压对抽油机井系统效率有显著影响,优化流压可以显著提高系统效率；含水率、气油比与饱和压力等油藏参数是影响合理流压的主要因素.%It has been a significant issue to calculate the reasonable flowing pressure of the rod pumping wells is the important scientific research subjects in the petroleum engineering and the oil reservoir engineering field. In this paper, the maximum of the system efficiency of the rod pumping unit is taken as the evaluating index of the reasonable flowing pressure, and a method is developed for calculating the reasonable flowing pressure of rod pumping wells. Using this method, five simulating models are set up as follows: 1) the effective power of the rod pumping wells based on the multiphase flow; 2) the input power of the motor based on the simulations the dynamic behaviors of the sucker rod string and the dynamometer cards of the polished rod; 3) the functional relations of the system efficiency with the flowing pressure, oil reservoir parameters and suction parameters; 4) the maximum system efficiency at a given flowing pressure; 5) the relations of the maximum system efficiency with the flowing pressure. The results of simulation show that: 1) the system efficiency of the rod pumping well is greatly affected by the flowing pressure, and the system efficiency can be increased by optimizing the flowing pressure; 2) the oil reservoir parameters of the water content ratio, the gas/oil ratio and the saturation pressure are the major parameters which affect the reasonable flowing pressure.
  • 摘要：The full potential linearized augmented plane wave (FP-LAPW) method based on the density functional theory (DFT) of the first-principles is applied to study two frequently proposed models of Fe3O4 (001) surface, the A-tenninated surface (A-tnodel), and the B-terminated surface (B-model). The atomic positions are initially optimized through relaxation, and the calculation of the density of states (DOS) and band structures shows that the half-metallic properties of A-model (FeA-terminate surface) are destroyed, differing from the properties of bulk Fe3O4 due to surface states. However, B-model (FeB and O terminate surface) keeps half-metallic properties.%通过第一性原理,基于密度泛函理论框架下的全势线性缀加平面波方法,分别对Fe3O4(001)表面两个不同的模型A模型(以四面体内的Fe为终端)和B模型(以八面体内的Fe和O为终端)进行研究,首先通过驰豫找到最优的原子位置,然后分别通过对两个不同模型态密度和能带的计算得出A模型自旋向上和自旋向下费米能级附近都有电子占据失去了半金属性,B模型费米能级附近自旋向下有电子占据,而自旋向上费米能级处有个明显的带隙,所以仍然保持半金属性,从能带中可以看出A模型半金属性的破坏是由于其表面态的影响.
  • 摘要：提出了一种Nb微合金钢中固溶Nb和非固溶Nb定量测定的方法.该方法包括化学溶解、过滤分离和电感耦合等离子光谱分析等步骤.结果表明:利用该方法可以准确地分析钢中固溶Nb的含量.该方法可以用于研究Nb在加热过程的溶解行为、热变形过程中析出行为,为定量研究Nb在钢中的作用提供一个有效的途径.%A quantitative analysis method is developed to study the content of soluble Nb and undissolved Nb in Nb-bearing steels. The test procedure involves chemical dissolution, filtration and Inductively Coupled Plasma Atomic Emission Spectroscopic (ICP-AES) analysis. The data by the method prove to match well with the original content, suggesting a potential application in the Nb dissolution and precipitation behaviors during steel reheating and hot deformation processes.
  • 摘要：The circulating fluidized bed boiler (CFBB) is a complex controlled plant, so the conventional control methods can not receive a good control effect for CFBB. In this paper, according to fuzzy control theory and neural network, a fuzzy neural network controller is proposed. By reasonable design of the neural decoupling network, the controller can not only adapt to the variable parameters of the controlled plant, but also can realize the decoupling of main steam pressure and bed temperature for CFBB combustion process. The simulation test and application in the field results show that the controller has excellent control effect to CFBB combustion process.%循环流化床锅炉是一种比较复杂的被控对象,采用常规的控制方法难以收到好的控制效果.在本文中,根据模糊控制理论和神经网络技术,一种模糊神经网络控制器被提出,通过对神经解耦网络的合理设计,使得该控制器不但可以适应被控对象的变参数运行工况,而且可以实现循环流化床锅炉燃烧过程主汽压力与床层温度的解耦.仿真试验和现场应用结果证明,本文提出的模糊神经网络控制器对循环流化床锅炉燃烧过程具有良好的控制效果.
  • 摘要：A model predictive control method is proposed for networked control systems with input constrain. Transmission time-delay and data packet dropout are both considered in the networked control systems. Given the upper bound of consecutive data dropout and time delay, the corresponding period control input generated by the predictive controller is designed to compensate for the time delay and packet dropout. Through setting up a time delay state matrix to classify the system model and regarding the systems as switched systems, sufficient stability conditions are established via a kind of switched Lyapunov function approach. In order to improve the system performance and to save the calculated amount, a part receding horizon optimization was used to design the controller. The upper bound of constant index and the sufficient condition of asymptomatic stability are given, and the state feedback law can be calculated by solving linear matrix inequalities. Validity of the proposed method is verified with simulations.%针对具有传输时延和数据包丢失的网络化系统研究了有约束模型预测控制问题.考虑网络控制系统中同时存在时延和丢包的情况,给定时延和丢包的上界值,用预测控制器产生的对应时刻的控制输入补偿网络时延和数据包丢失,通过建立时延状态矩阵将系统模型进行分类并视为切换系统,并通过构造切换Lyapunov函数证明了切换系统的稳定性.为了在提高系统性能的基础上减少计算量,利用部分滚动优化方法进行控制器设计,给出了性能指标的上界和系统渐进稳定的充分条件,通过在线求解LMI问题得到状态反馈控制律.仿真研究验证了该方法的有效性.
  • 摘要：考虑信源有多根天线、中继和终端均只有单根天线的两跳中继转发系统.为了获得空间分集,信源利用了正交空时分组编码的发射策略.为了尽可能简化中继配置的复杂度,中继采用固定增益放大转发的协议.导出了瑞利衰落下系统中断概率和误码率的封闭表达式,并通过计算机仿真和数值结果的比较,验证了理论导出表达式的精确性.%A two-hop relaying system in which the source are equipped with multiple antennas, while the relay and destination only have a single antenna is considered. OSTBC strategy is employed at the source to achieve space diversity. To make the complexity of the relay lower, fixed gain amplify-to-forward protocol is used. The closed-form expression for outage probability and average SER are derived in Rayleigh fading environment. Finally, Monte Carlo simulations are .compared to numerical results to validate the theoretical expressions.
  • 摘要：提出了一种基于相对熵和子空间二次过滤的CLIQUE改进算法.该算法根据数据的分布情况对每一维采用自适应的网格划分方法,减少了全空间中网格单元的数量,降低了算法的时间复杂度.算法采用了基于维关联度的子空间二次过滤策略,提高了聚类结果的准确性.实验使用仿真数据表明,该算法在精度,时间复杂性等方面的表现优越.%A improved CLIQUE algorithm based on relative entropy and subspace re-refinement is proposed. The algorithm adopts the technique of adaptive grids according to the distribution of the datasets to reduce the number of the grid in the full data space, hence reduce the time complexity of the algorithm. The algorithm uses the punning refinement strategy based on the correlation of dimensions to enhance the accuracy of the clustering results. Experiments on synthesis datasets show that the new algorithm achieves a gain of runtime and quality to find subspace clusters.
  • 摘要：The goal of one-class classification model is to design the covering model for the target class. The model should ideally cover the objects of target class, and reject all other non-targets. The support vector data description (SVDD) aims to find the minimum ball enclosed all the target objects. However, this model couldn't perform better for the data with irregular and complex distribution. The convex hull data description (CHDD) based tight covering model is presented in this paper. The model is a non-parametric classifier which covers the irregular data adaptively in the feature spaces. By the introduction of kernel functions, the stronger ability of nonlinear classification could be obtained. When the training set of target class contains outliers, the model can be made more robust by rejecting a fraction of the training objects. The experimental results show that the presented method performs better by comparing its results on the UCI, MNIST and MIT-CBCL face data sets with other one-class cl assification methods.%一类分类问题的研究目标是设计目标类样本的覆盖函数,理想情况下使得目标类样本被接受,所有非目标类的样本被拒绝.经典SVDD覆盖模型寻找包含训练数据的最小半径超球对其进行覆盖,该模型对非规则复杂分布的数据描述存在较多的冗余区域.本文提出一种基于训练集样本凸壳数据描述(Convex Hull Data Description,CHDD)的紧致覆盖模型.该模型无须参数设置,可实现对样本非规则复杂分布的自适应覆盖,并可通过利用核函数方法获得更强的非线性分类能力.当训练集包含噪声样本时,通过拒绝一定比例的目标类样本可获得更为鲁棒的凸壳边界描述.在UCI数据库、MNIST手写体数据库和MIT-CBCL人脸识别数据库上的实验结果表明了本文方法的有效性,相比现有一类分类算法,CHDD取得更好的分类效果.
  • 摘要：An electromechanical integrated electrostatic harmonic micro drive is proposed. As reducing the dimension of the drive, the influence of the molecular forces is increased and should be considered. The forced response equations of the flexible ring for the drive to the electric excitation are deduced by considering electrostatic and the Casimir forces. Using the equation, the influences of the Casimir force on the forced responses of the flexible ring to the electric excitation are investigated. Results show: the Casimir force has obvious influences on the forced responses for the drive. As the initial clearance drops and the voltage grows between the flexible ring and the stator, the influences becomes larger. The results are useful in theory and technique studies on further miniaturization of the drive.%提出一种机电集成静电谐波微型传动系统.随着传动尺寸的减小,分子力的影响变大,应该予以考虑.本文给出了同时考虑静电力和Casimir力时机电集成静电谐波微型传动系统对于电压扰动的强迫响应方程.运用该方程,研究了Casimir力对系统强迫响应的影响规律.结果表明:Casimir力对于系统强迫响应具有重要影响,随着柔轮与定子间初始间隙的减小和电压的增大,Casimir力对系统强迫响应的影响变大.研究结果对于该种传动系统的进一步小型化具有指导意义.
  • 摘要：将传统的PID控制器与神经元网络融合,建立PID神经网络.运用VB语言编译了拉深过程中变压边力控制系统的PID神经网络仿真程序,并与传统的PID控制仿真进行了对比.建立了基于PIDNN的变压边力控制系统,并通过锥形件拉深实验,证实了PIDNN控制系统具有精度高,抗干扰能力强,能较准确达到变压边力控制要求等优越性.为后续的变压边力控制系统实验研究与工厂实际应用提供了理论与实践基础.%A PID neural network (PIDNN) based on the integration of PID controller and neural network is built. The PIDNN simulation program of variable BHF control system in deep drawing is compiled with VB, and compared with the traditional PID control simulation. Variable BHF control system based on PIDNN is built, and through the cone-shaped drawing experiment, PIDNN system is confirmed to have the advantages of high precision, anti-interference ability and achieving accurate control of variable BHF requirements, which provides theory and practice foundation for the further experiment and practical application.
  • 摘要：将时间序列的AR模型引入到旋转机械故障诊断中,采用了经验模态分解与AR模型相结合的方法提取旋转机械的故障特征.通过选取含有故障信息的固有模态函数进行功率谱分析,提取故障特征,分析故障原因.仿真和试验结果表明,此法能够有效地提取故障特征参数,为旋转机械的故障诊断提供了方法保障.%The auto regressive model for time series prediction is introduced into rotating machinery fault diagnosis. The empirica mode decomposition and auto regressive model forecast parameters are put in use to extract the characteristics of rotating mechanica failure. To extract the fault feature and analyze the fault cause, the IMFs relating to fault information are applied to AR spectnirr analysis. It is verified that the method yields effectively the characteristic parameters of fault. This work is helpful to diagnose th< rotating machinery fault.
  • 摘要：A review was presented on the current research of carbide-derived carbons (CDCs). The preparation, microstructure and composition as well as application of CDCs in the fields of tribology and energy were introduced. The possible problems and applications of CDCs in the future were predicted.%评述了碳化物衍生碳的国内外研究现状,主要介绍了碳化物衍生碳的制备方法、结构与组成、在摩擦学及能源领域的应用,预测了碳化物衍生碳在今后的发展趋势.
  • 摘要：水幕系统对火焰辐射衰减问题包含了气体、水滴粒子、不完全燃烧产生的炭黑粒子等吸收、散射以及液滴蒸发吸热等过程.针对此问题,本文首先采用Mie散射理论与有效介质理论相结合,建立了水滴粒子以及炭黑掺杂混合液滴的吸收散射特性参数计算模型;在此基础上,考虑燃气辐射吸收作用,采用球谐函数法构造了多层半透明水幕介质的辐射传输计算模型.利用该模型分析了载液量、液滴粒径、水滴蒸发、粒子混合等因素对辐射衰减能力的影响.%The problem of thermal radiation shielding through water curtains is very complicated including absorption, scattering and evaporation absorbing heat processes of gases, water droplets and soot particles. In this paper, the Mie theory and effective medium theory are combined to build the model calculating absorption and scattering parameters of water droplet and mixed droplet containing soot particle, on this basis, taking into account the gases absorption effect the numerical model of radiative heat transfer in the multi-layer semitransparent water curtains are established using Pn-approximation method. By present model, the influence of droplet loading, droplet size, droplet evaporation and droplet mixing on the thermal shielding are systematically simulated and analyzed.
  • 摘要：A high Cr cold roller steel with nitrogen was compressed in the temperature range 950~l200℃ and strain rate range 0.1-10 s-1. The mechanical behavior has been characterized using stress-strain curve analysis, kinetic analysis, processing maps, etc. Metallographic investigation was performed to evaluate the microstructure evolution. It was found that the work hardening rate end flow stress decrease with increasing deformation temperature and decreasing strain rate in Cr8N steel; the efficiency of power dissipation decreases with increasing Z-value; the deformation activity energy and stress exponent are 542 kj/mol and 5.25, respectively; the hot deformation equation and the relationship between peak stress and Z-value are also obtained.%对一种8％Cr冷轧辊用钢在950～1 200℃以0.1～10 s-1的变形速率进行热压缩变形,通过流变曲线分析、动力学分析及热加工图技术等方法表征其热变形时的力学行为,并对变形后的显微组织进行观察.结果表明:Cr8N钢的加工硬化率和流变应力随着变形温度的升高和应变速率的降低而降低,功率耗散百分数随着Z参数的增大而降低；上述变形条件下Cr8N钢的热变形激活能为542 kJ/mol,加工硬化指数为5.25；获得了该钢的热变形方程以及Z参数和峰值应力间的关系.
  • 摘要：提出了一种抑制正交频分复用(OFDM)系统峰均功率比(PAPR)的融合算法,该算法在OFDM系统发射端对信号先后进行选择映射(SLM)和压扩变换,从而使信号的峰均比得到二次抑制.仿真结果说明了该算法对峰均比的抑制效果比单独使用SLM技术和压扩技术都有明显的改善,并且对于计算复杂度要求不高的OFDM系统,不同参数的综合技术可相互替代以提高系统的误码性能.%A combined scheme for PAPR {peak-to-average power ratio) reduction in OFDM (orthogonal frequency division multiplexing) system is proposed. The PAPR can be reduced twice by using SLM (selected mapping) technique and compounding technique. Simulation results show this method can get better PAPR performance than using the above techniques alone. In the OFDM system which has not too much requirement in computational complexity, the schemes with different parameters can be replaced each other to obtain better BER performance.
  • 摘要：Large numbers of duplicate elements contained in discernibility matrix may employ a lot of memory. When the dataset is dense, the time complexity of constructing discernibility matrix is very high. In this paper, an attribute reduction algorithm SDMAR based on simplified discernibility matrix is proposed. Firstly, the attributes are merged by calculating the attributes similarity and the same individuals in universe are deleted before reducing attribute, then a simplified decision table is got. Secondly, simplified discernibility matrix is constructed according to reduction decision table. To achieve the purpose of attribute reduction, the attributes occurred most frequent in discernibility matrix are found and the elements included these attributes are deleted, until discernibility matrix is empty. The analysis of the algorithm and a case shows the time complexity of attribute reduction is low.%差别矩阵中会出现大量的重复元素占用大量内存,当数据太稠密时,构成的差别矩阵太大不容易操作且计算代价较高.本文提出了一种基于简化差别矩阵的属性约简算法(SDMAR),在属性约简之前,通过计算属性相似度,对属性进行了合并操作,得到简化决策表.根据简化决策表构造差别矩阵,计算差别矩阵中出现次数最多的属性并删除包含该属性的元素,当差别矩阵为空时终止操作,以达到对决策表属性约简的目的.通过算法及实例分析得到属性约简过程的时间复杂度有所减小.
  • 摘要：Recently, it becomes a very important research direction and a front technology to study the theory and the application of the various novel limited-DOF parallel manipulator (PM). The essential differences between limited-DOF PMs and 6-DOF PMs lie in the structure constraints appear in this class PMs and thus the constrained forces/torques appear in the sub chains of this class PMs. The terminal of limited DOF PMs is restrained and the kinematics of the terminal is coupling. Due to the different structure constraints, the limited DOF PMs possess various kinematical characteristic. In fact, many properties of this class PMs are related to constraints. In this paper, the development of the type synthesis, the kinematics analysis, the singularity analysis, the dynamics analysis and the stiffness analysis of the limited-DOF PMs have been evaluated comprehensively in order to provide important and valuable information for studying the theory and the application of the various novel limited-DOF PMs.%各种新型少自由度并联机构的理论和实验研究是近年来国内外机器人领域中十分重要的研究方向和前沿技术.与6自由度并联机构相比,其本质差异在于少自由度并联机构存在结构约束,使并联机构的分支中出现了约束力/矩.当机构运动受到约束,其末端运动呈现耦合.由于结构约束形式各异,使得少自由度并联机构在运动中表现出不同的运动特性.本文综合评述了少自由度并联机构机型、运动学、机构奇异、动力学、刚度研究进展,旨在为各种新型少自由度并联机构研究和相应理论体系的发展提供具有重要价值的信息.
  • 摘要：在分析2-UPU/2-URU并联机构结构特点的基础上,运用封闭法对机构进行了位置分析,并验证了数值特例,利用球坐标搜索法得到影响并联机构工作空间的各种约束条件下的边界点,并通过MATLAB软件绘制工作空间的三维图形,得到约束条件对工作空间的影响规律,说明了其工作空间分布的特点,并进行了奇异分析.该机构是一种过约束机构,本文的研究为该机构工作空间优化设计和机构尺寸设计提供了依据,为该并联机构进一步的研究奠定了基础.%A novel over-constrained 2-UPU/2-URU parallel mechanism is proposed. First, its displacement kinematics is analyzed using a closed method, the numerical solutions are obtained and verified based on its analysis of the structural characteristics. Second, the boundary points under constraint conditions which influence its workspace are obtained, and its three-dimensional workspace is constructed using MATLAB software. Third, the rules that constraint the influence workspace are obtained, the characteristics of workspace distribution is demonstrated, and the singularity is analyzed. The studies of this parallel mechanism provide a basis for the optimization of workspace and the dimension design of this mechanism and a foundation for further study of this parallel mechanism.
  • 摘要：The parameters of a solar air collector with internal baffles are optimized by numerically solving Reynolds-averaged N-S equations (RANS) and energy equations. The simulation results are obtained by changing the structure, the property of some components and the operating parameters. The obtained results show that the introduction of baffles can increase the collecting efficiency. For specific scale collector, there is an optimal chamber number. Enhancing the heat insulation of top cover plate can effectively improve the efficiency using double-glasses top cover plate or increasing the thickness of air gap properly. The convective heat loss of the top cover plate is dominative in the total heat loss, and the radiation heat loss is relatively little The operating parameters such as the surrounding temperature, solar radiation intensity have great influence on the temperature rise between inlet and outlet but have little influence on collecting efficiency.%通过数值求解基于雷诺时均的三维定常粘性N-S方程及能量方程,改变结构、特性及运行参数,对折流板型太阳能空气集热器进行了数值优化,模拟结果表明:折流板的引入可有效提高集热效率,同时对于特定尺度的折流板集热器,存在最优分割腔数；增加集热器上部盖板的保温能力可有效提高集热效率,实际使用中推荐保温能力较好的双玻盖板或适当增加空气间层厚度；集热器的热损失以对流散热占主导,辐射散热为次要因素；运行参数如气温、日照强度等对集热器进出口温升影响显著,但对集热效率影响较小.
  • 摘要：A new high-carbon low-alloy steel is designed to obtain the carbide-free bainite under low-temperature austempering. The microstructure, wear resistance under dry sliding friction and the wear mechanism are comparatively studied between samples austempered and low-temperature tempered. Results show that the carbide-free bainitic microstructure composed of bainitic ferrite laths with mean thickness of 120 nm and retained austenite films can be achieved by austempering at 220 °C for 120 h in salt bath after austenitizing at 1 000 °C. The wear resistance under dry sliding friction of austempered sample is 19% more than that of low-temperature tempered sample. The wear mechanism of the low-temperature austempered sample is determined to follow the adhesive wear mode.%设计了一种新的低温等温转变无碳化物贝氏体高碳低合金钢.对该钢低温等温淬火组织和干滑动摩擦磨损耐磨性及磨损机理进行研究,并与淬火+低温回火处理试样进行比较.结果表明,经1000℃奥氏体化后在220℃盐浴中进行等温120 h的等温淬火处理,得到了由平均厚度约为120 nm的板条状贝氏体铁素体和薄膜状的残留奥氏体组成的无碳化物贝氏体组织,干滑动摩擦磨损相对耐磨性比回火马氏体组织提高19％,磨损机理为粘着磨损.
  • 摘要：The studies of composites usually emphasize two basic aspects of water absorbing capacity and corrosion resistance. In this paper, the two properties are focused in the composites of epoxy resin and hollow glass beads (HGB/EP) with the water absorbing capacity being tested at room temperature and 60 °C, and correosion resistance in the acid and alkali conditions at 60 ℃ The studies aim at revealing the moisture absorption characteristics and the influence of temperature on the water uptake and the corrosion behavior of materials at 60 'C. Water absorption in the composites is found to correlate with beads filling volume ratio and the microstructure of HGB/EP. It is also observed that high temperature can enhance the moisture absorption rate and balance the moisture absorption. The corrosion test shows that the composites have poor acid resistance, and the samples display a softening effect after the tests. The higher acid concentration basically cause more serious corrosion, leading to the reduction of the mechanical properties of the composites.%在对复合材料的研究中,其吸水性及耐腐蚀性一直是研究的重点之一.本文通过常温和60℃吸水试验以及60℃酸、碱腐蚀试验,研究了空心玻璃微珠填充环氧树脂制成的复合材料(HGB/EP)的吸湿规律、温度对吸湿的影响以及材料在60℃下的腐蚀情况.通过研究不同配比的空心玻璃微珠(HGB)与环氧树脂制成的复合材料吸水量的大小,发现这种材料吸水量大小与微珠的填充率密切相关,不同填充比复合材料其微结构对吸水量影响甚大,且高温能提高吸湿速率和平衡吸湿量.在腐蚀试验中,发现该材料的耐酸性较差,测试后试件表现出软化现象.而酸的浓度越高,腐蚀越严重,经浸泡腐蚀的材料力学性能进一步下降.
  • 摘要：针对使用椭圆形剪切屈服面的非饱和土BBM弹塑性模型计算抗剪强度偏低的问题,提出了非饱和土水滴形剪切屈服面函数,对原模型进行了改进,将水滴形屈服面扩展到非饱和土中,提出了非饱和土水滴形剪切屈服面函数,采用相关联的流动法则改进了BBM模型.通过对同一组试验的数值模拟,对比研究了改进模型的合理性以及与原模型的差别,结果表明,在控制吸力条件的三轴压缩状态下采用水滴形屈服面的改进BBM模型对非饱和土强度及变形的计算更为合理.%The shear yield surface of ellipse is adopted to the elastic-plastic model of BBM so that the results of shear strength are low for unsaturated soil. To solve this problem, the drip type yield surface was extended to unsaturated soil, then the shear yield surface function of drip type for unsaturated soil was proposed, while the associated flow rule was also used to improve the BBM model. Through the numerical simulation to the same set of experiments, the shear yield surface of drip type and ellipse for BBM elasto-plastic model have significant difference on predicting of strength and deformation behaviors of unsaturated soil. The results show that improved model of drip type yield surface can more accurately predict the strength and deformation behaviors of unsaturated soil under suction-controlled triaxial compression stress states.
  • 摘要：《燕山大学学报》是由燕山大学主办的自然科学类学术刊物，双月刊，国内外公开发行，中国科技核心期刊。本刊以“出精品、创名刊、凝特色、促交流、举人才”为办刊宗旨，主要刊登机械、材料、电气电子、计算机与通信等学科原创性论文。
  • 摘要：A simulation model of the plastic-steel material spiral worm gear is established using software Simscape according to the principle of thermal network in order to analyze the heat transfer of this worm gear. The power loss and the heat resistance calculation model are obtained. The temperature and heat flow distribution is simulated. The simulation results show that the temperature of the worm is far higher than that of the other node, the heat is mostly transferred by heat conduction. Thus the most efficient way to improve the heat transfer of the gear is for improving the conduction of the worm.%为了获得塑料-钢材料的螺旋齿蜗轮蜗杆啮合过程中的热量分布,根据热网络分布原理,利用Simscape仿真软件建立了热网络模型,分析了其啮合时的功率损失,得出其热阻计算模型和系统的稳态温度分布及热流量分布.仿真结果表明,蜗杆的温度远远高于其他节点温度,齿轮主要以蜗杆热传导的方式散热,通过选择热传导系数更大的蜗杆材料或采用减小蜗杆长度的设计可以改善蜗杆端传导散热.
  • 摘要：针对在带钢冷轧过程中辊系热变形问题,建立了轧辊温度场与热变形的仿真模型.为了提高模型精度,依据热像仪实拍的辊面温度场信息、轧制过程数据分析得到的轧辊热膨胀信息,对关键参数采用遗传算法进行了优化.优化后的仿真结果与现场信息基本一致,提高了仿真精度,为轧辊热变形的准确预报打下了基础.%In the light of roller thermal deformation, a finite difference numeric model is established. Some important parameters are optimized in order to improve the precision of the model based on the temperature field of the roller surface acquired with infrared thermal camera and the radial thermal expand mined from data of rolling process. The simulation results of optimal model are coincident with that of temperature field of the roller surface and radial thermal expand information. The precision of the model is improved, and it provides a foundation for prediction of the roller thermal deformation.
  • 摘要：利用纳米压痕技术研究了热处理对聚(2-甲氧基-5-(2'-乙基己基氧)-1-4-苯撑乙烯)(MEH-PPV)薄膜力学性能的影响,结果表明:随着热处理温度的提高,最大压痕深度先减小后增加,弹性模量、硬度随着热处理温度的提高而降低；另外,MEH-PPV薄膜对负载率的敏感性随热处理温度的提高而降低；同时利用高斯网络模型分析了热处理对MEH-PPV薄膜力学性能影响的原因,拓扑缠结对MEH-PPV薄膜力学性能影响是主要的,而凝聚缠结对MEH-PPV薄膜力学性能影响是次要的.%The effect of heat treatment temperature on the micro mechanical behaviors of MEH-PPV thin film is studied by nanoindentation test. The elastic modulus and indentation hardness decrease with increasing quenching temperature. The sensitivity of the MEH-PPV film micro mechanical behaviors on the load rate is depressed when the quenching temperature increases. The effect of quenching temperature on the micro mechanical behaviors is analyzed by using Gauss network model, indicating that the mechanical behaviors are governed mainly by the topological entanglement, rather than the cohesive entanglement.

    燕山大学学报的期刊信息

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    燕山大学学报的获奖情况

    • • 2011年，被河北省高等院校学报研究会评为河北省教育系统优秀期刊
    • • 2015年，被河北省新闻出版广电局、河北省期刊协会评为河北省优秀期刊
    • • 2016年，被中国高校科技期刊研究会评为2016年度中国高校优秀科技期刊
    • • 2017年，被河北省新闻出版广电局、河北省期刊协会评为河北省十佳期刊
    • • 2018年，被中国高校科技期刊研究会评为2018年度中国高校优秀科技期刊

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    • • 北大核心期刊（2014版）
    • • 北大核心期刊（2017版）
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    • • 中国科技核心期刊

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