摘要:The Saihantala Sag in Huabei Oil Field is a typical reservoir of low porosity and low permeability .In this paper we analyze the block geological features ,core test data ,geological da-ta ,logging data and its response characteristics ,study the effective methods for calculation of car-bonate content using the well logs ,and then establish the physical parameters calculation model based on carbonate content .It provides a basis for improving well log interpretation coincidence rate .%赛汉塔拉凹陷储层为典型的低孔低渗储层。根据该区块地质特征,在分析其岩心实验资料、地质资料、测井资料及其响应特征的基础上,进一步研究利用测井曲线计算碳酸盐含量(体积分数)的有效方法,进而建立了基于碳酸盐含量的孔隙度、渗透率计算模型,为提高测井解释符合率奠定了良好的基础。
摘要:介孔分子筛具有均一可调的介孔孔径、较高的比表面积等一系列优异特性,成为当今国际上研究热点之一。文中从介孔分子筛的性能、合成、改性以及应用等方面进行了综述和展望。结合我们课题组的研究工作,对目前研究较多的介孔分子筛的合成方法,如水热法、室温合成法、微波辐射法等进行了概括,同时还概述了模板剂在分子筛合成中的应用以及以稻壳为原料制备介孔分子筛的研究情况。重点讨论了在提高介孔分子筛酸性和水热稳定性方面的研究工作,为研究以稻壳为硅源来制备介孔分子筛以及对分子筛的改性提供了一些思路与方向。%Mesoporous molecular sieve is an interesting research area because of its excellent properties ,such as adjustable uniform mesoporous pore size and high specific surface area .In this paper ,we introduced the properties ,synthesis ,modification and application of the mesoporous molecular sieve .Base on our research works ,we reviewed the synthesis methods in the present studies ,such as hydrothermal method ,room temperature conversion method and microwave radi-ation method ,etc .Meanwhile ,we overviewed the function and application of template used in the synthesis of molecular sieves and the preparation of mesoporous molecular sieves from rice husk .The research works on the improvements of the acidity and hydrothermal stability of meso-porous molecular sieve were summarized mainly .All the above provided some ideas and direction for the preparation and modification of mesoporous molecular sieves from rice husk .
摘要:To improve the precision of area measurement of land ,based on Gauss projection ,this paper used the multiple location averaged method and the PauTa criterion to improve the precision of point po-sitioning in ground investigation ,used the trace mathod and route method to calculate the area of regular rigion and used the trace method and the intrpolation method to calculate the area of irregular region .It proved that the route method could improve the precision of area measurement for regular region and the interpolation method could improve the accuracy of area measurement for irregular region .%为了提高土地面积测量精度,在高斯投影的基础上,采用算术平均值法和拉依达准则提高土地勘察中G PS单点静态定位精度,在此基础上,以航迹法和航线法计算规则地形面积进行比较,以航迹法和分段二次插值法计算不规则地形面积进行比较。结果表明,采用航线法可以提高规则地形面积测量精度;分段二次插值法可以提高不规则地形面积测量的精度。
摘要:汽车线控转向系统取消了转向盘与转向轮之间的机械连接,通过力反馈装置提供转向时的转向盘阻力矩以实时提供路感反馈。路感反馈是线控转向系统的核心技术之一。总结了线控转向系统的国内外研究现状、实现线控转向系统路感反馈的几种典型结构和路感产生的机理,分析了线控转向系统路感反馈的多种控制算法和控制方法;研究了线控转向系统路感反馈的实验方法,为研发线控转向系统提供了参考。%Automobile steer by wire system disconnects the mechanical link between the steering w heel and steerable w heels so the reaction torque on the steering w heel should be provided by the torque feedback device to realize the road feel feedback real time w hen steering ,w hich is one of the key technologies of steer by wire system .First ,current status of steer by wire system at home and abroad are summarized .Then ,several typical structures of steer by wire system are an-alyzed ,followed by introduction of several road feel feedback control algorithms and control methods of steer by wire system .Finally ,test methods of steer by wire system are presented . Our work provided a reference for further research of steer by wire system .
摘要:基于现场条件合理选用监测系统,并运用各系统对工作面各项矿压参数进行实时在线监测。以工作面某次压力异常期间各系统预警情况为研究对象,通过对预警信息和现场情况进行分析,及时采取了大直径钻孔卸压、爆破解危、煤层注水卸压等解危卸压措施,成功将工作面高应力区域进行了深部转移,保护了作业空间的安全。研究表明,各监测设备运行情况稳定,在深部煤层回采工作面矿压规律研究、灾害预测预报及指导现场工程等工作中各监测设备适用性良好,可以满足相关需求。%In this paper ,we selected appropriate monitoring system based on conditions in the field ,and used the system to real-time online monitor various pressure parameters of working face .For example ,in the face during of an abnormal pressure system warning ,warning informa-tion was analyzed in a timely manner ,the large diameter borehole pressure relief ,pressure relief blasting danger-breaking and coal seam water infusion were carried out ,the high stress inworking face wrer suqessfully transferred into deep regions and the operation space were protected .The results show that the monitoring system runs stably and it has a good application in the study of the pressure rule in deep coal seam ,disaster forestast and other engineering work .
摘要:In order to achieve the optimum power performances of pure electric minivan ,we anal-ysis the design of power system parameters .Combined with the certain van ,the mode of multi-transmission ratios with fixed final ratio is adopted and all needed power system parameters are pre-determined .Then ,we establish simulation models and operate tasks of calculation of the transmission ratio in Cruise .The selected power system parameters is optimized by analyzing simulation results to reach the power performances requirements and improve the transmission ef-ficiency .The results show that the design of optimum transmission ratio meets requirements of power performances .The method of optimization and simulation in this paper has practical guid-ing significances in electric minivan match and simulation analysis .%为了使微型纯电动货车具有最佳的动力性能,对动力系统参数进行设计分析。结合给定的车型,采用固定主减速比的多档传动方式,预选各动力传动件参数。在Cruise软件中建立整车仿真模型,通过设定任务完成仿真计算。并结合仿真结果,对选取的各传动件参数进行优化,使其达到动力性要求的同时,提高传动效率。结果表明:设计能够以最佳传动比满足目标动力性能要求。
摘要:A double-level design is presented in this paper in order to achieve bus signal priority under arterial signal progression ,the upper level is progress control ,in w hich the largest green wave band method is adopted to optimize the main intersection of public cycle ,green ratio and phase difference based on the data of car flow detector and the lower level is bus priority control in which green extension and red truncation are adopted to achieve bus signal priority under the condition of signal coordination .According to the algorithm ,bus priority control process is estab-lished using the microscopic simulation software transmodeler simulates validation .The simula-tion results show that the control of bus priority under coordinated control algorithm can reduce bus delay and the average delay per line although increase the trunk delay .%为了在干线协调控制下实现公交信号优先,提出了干线协调控制下的公交优先双层优化方法。上层为干线协调层,以检测到的社会车辆信息为依据,采用最大绿波带法,优化干线交叉口的公共周期、绿信比和相位差;下层为公交信号优先,以干线协调控制层的绿波带上下限为控制约束条件,在不破坏约束的条件下采用绿灯延长、红灯早断的公交优先控制策略,将公交优先融合到干线协调控制中。根据优化算法,建立公交优先控制流程,利用微观仿真软件T ransmodeler进行了模拟验证。仿真结果表明:协调控制下的公交优先控制算法虽然会导致干线总体车均延误增加,但是能有效减少公交车辆延误和干线人均延误。
摘要:Based on logging data and rock physical experiment data ,this article analyses the Wuqi chang 6 reservoir characteristics ,proposes the qualitative identification method that using the re-sistivity relative value to divide oil and water layer ,and establishes the qualitative identification standard .This method has high practical value in the reservoir evaluation and has laid a good foundation for reservoir logging evaluation in Wuqi area .%依据吴起地区测井资料、岩石物理实验资料,对长6储层特征进行了分析,提出利用电阻率相对值划分油、水层的定性识别方法,并建立了定性识别标准。该方法在储层评价中具有较高的实用价值,经实际应用,效果良好,为吴起地区储层测井评价奠定了良好的基础。
摘要:在捷联惯导系统设计开发过程中,采用嵌入式代码自动生成技术,将理论设计过程中产生的Simulink仿真程序直接转换为可在嵌入式系统中执行的C语言代码,以达到缩短研发周期、降低成本的目的。经过实际验证,自动生成的代码可以完成系统功能要求,具有较高的实际使用价值。%Strap-down intertial navigation system (SINS) is widely used in missile's navigation system .Beacuse the engineer of theory are not familiar with embedded system ,the code engineer was hired to complete the preparation of the code .Therefore ,the development cycle and costs are increased .Using RTW to transform the simulation model to C language can solve this problem . The actual test confirms that this method has a high practical value .
摘要:Accurate modeling of cam mechanism is built using PRO/E ,and it is introduced into ANSYS/LS-DYNA using the seamless connection between PRO/E and ANSYS . The stress , strain distribution of cam mechanism at every moment and the trajectory of push-rod can obtained using finite element dynamic analysis software ANSYS/LS-DYNA ,to verify whether the cam mechanism could meet the design requirements .%利用PRO/E对凸轮机构进行精确建模,采用PRO/E和ANSYS的无缝连接,将模型导入ANSYS/LS-DYNA中。利用有限元动力分析软件ANSYS/LS-DYNA 得到凸轮机构在每一时刻的应力、应变等分布情况和推杆的位移变化规律,从而验证凸轮机构是否满足设计要求。
摘要:针对移动机器人在未知环境下的全遍历覆盖任务,将滚动规划与已知环境下的搜索策略相结合,设计了一种混合式的全遍历覆盖路径规划算法。对声纳传感器探测到的环境信息进行滚动规划,把未知区域转化为已知区域。在已知区域,采用有限状态机方式来组织全遍历覆盖路径规划算法,状态之间的转换通过二叉树搜索策略、目标栅格选取策略和两点法搜索策略来实现,并对算法进行仿真。结果表明,移动机器人能全遍历覆盖整个工作区域,重复率低,能有效提高工作效率。%This paper presents a hybrid design algorithm of complete coverage path planning for mobile robot under unknown environment based on the rolling planning and known environment search strategy .The unknown environment has been converted to the known area using the envi-ronmental information detected by sonar sensors .The algorithm of complete coverage path plan-ning is organized by finite state machine (FSM ) approach under the know n environment . T he state switch has been realized by the binary search strategy ,target grid selection strategy and two-point search strategy .At last the algorithm has been tested under simulated environment . Simulation results show that mobile robot can cover the entire work area with low repetition rate and high work efficiency .
摘要:Using the multivariate regression principle and with the aid of SPSS software ,the re-gression equation is established that among the lateral acceleration ,yawing angular velocity and steering tie rod force with tire pressure on the basis of the statistical analysis of data ,and the fea-sibility of the model is verified .The actual vehicle tire explosion performance has been made a forecast analysis .Predicted results can well reflect the relationship among the parameters ,the speed and the tire pressure .%在对实验数据进行统计分析的基础上,利用多元回归原理并借助SPSS软件,建立了侧向加速度、横摆角速度和转向横拉杆力与胎压、车速的回归方程,并验证了模型的可行性。对车辆实际爆胎工况的预测分析表明,预测结果能较好地反映各参数与车速以及胎压之间的关系。
摘要:数学模型参数的估计常采用经典统计方法,本研究将SAS程序和贝叶斯统计相结合,对非线性回归模型Y=(a+ bX)/X+ε进行参数估计,并通过实例演示验证了该方法的有效性,为统计方法提供了新的手段和途径。%For estimation of mathematics model parameter ,the classic statistics method is often adopted .The paper carried out the parameter estimation on non-linear regression model Y= (a+bX )/X+εby combining SAS program with Bayesian statistic .It also demonstrated some illustra-tions which verified the validity of the method .The study provides a new way for statistical meth-od .
摘要:The realization of fault feature extraction is the key point during the fault diagnosis in gearbox based on vibration signal analysis .Because the strong noise interference consist in the vi-bration signals which collected from the actual work gearbox ,it is hard to extract the fault fea-ture using single signal analysis method .Two different or more methods jointly used in gearbox vibration signal processing have been the tendency in current research .In order to study the ad-vantages of different methods jointly used in gearbox fault signal feature extraction ,we analyzed large amount of literature and found that the combining methods can avoid the limitations ap-peared in single method ,and make full use of the advantages in different methods .T he current situation of the application of combining methods separately based on frequency analysis and non-linear theory in gearbox fault feature extraction was summarized ,and finally some suggestions were made for the development of the different signal processing methods used in gearbox fault diag no sis .%基于振动信号分析的齿轮箱故障诊断的关键是实现对信号中故障特征的提取。由于在工程实际中采集到的齿轮箱振动信号含有较强的噪声干扰,所以单一的信号分析方法难以实现对故障特征的提取。因此将两种或两种以上方法相结合应用于齿轮箱振动信号的处理成为当前的研究趋势。为研究将不同方法相结合应用于齿轮箱故障信号特征提取的优势,对大量文献的研究成果进行了归纳整理。综合分析发现:将多种方法结合应用于齿轮箱振动信号特征提取,可有效避免单一方法的局限性,充分发挥不同方法的优势。总结了在齿轮箱故障诊断领域中分别以频谱分析为基础和以非线性理论为基础的将不同信号处理方法结合应用于齿轮箱故障特征提取的现状,最后针对多种方法结合应用于齿轮箱故障诊断的发展趋势提出了建议。
摘要:不确定性数据挖掘已经成为数据挖掘领域的新热点,频繁项集挖掘是重点研究的问题之一。但是目前出现的挖掘算法大多集中在完全频繁项集,而用于最大频繁项集和频繁闭项集的算法尚不多见。文中研究了一种基于U F-T ree的用于不确定性数据中挖掘最大频繁项集的算法,该挖掘过程分为两个步骤,第一步先得到以频繁1-项集为后缀的局部最大频繁项集,第二步得到所有的全局最大频繁项集,实验证明该算法性能良好且特别适用于稠密型、事务长度较小的数据集。%Recently ,the research on uncertain data mining has become a new hotspot in the area of data mining ,and the frequent itemsets mining is one of the focus issues .The existing algorithms mostly concentrated on the complete frequent itemsets ,and there is few algorithms used to mine maximal or closet ones .This paper proposes a new algorithm UMF-growth to mine maximal fre-quent itemsets from uncertain data .The mining process of the UMF-growth is divided into two steps :the first step is to find out all of the local maximal frequent itemsets with the frequent 1-i-tem as suffixes ,respectively .And the second step is to get all the maximal frequent itemsets . The experimental results show that the performance of UMF-growths is very good and especially suitable for the dense database .
摘要:在数据密集型计算环境中,数据具有海量、高速变化、分布存储和异构等特征,对数据挖掘算法的设计与实现提出了新的挑战.基于MapReduce模型,提出了一种网格技术与基于LOF方法相结合的离群点挖掘算法MR_LOF .Map阶段采用网格进行数据约简,将代表点信息发送给主节点;Reduce阶段使用基于密度的离群点挖掘算法,借助网格期望值E筛选出稠密区域.该算法只需计算稀疏区域对象的LOF值,降低了算法的时间复杂度.实验结果表明,在数据密集型计算环境中,该方法能有效的对离群点进行挖掘.%The characteristics of data ,such as huge amounts ,high dimension and distributed storage etc ,have brought new challenges for the design of outlier mining algorithm in data-inten-sive computing environments .In this paper ,outliers mining algorithm M R_LOF based on density combined with grid was put forward on account of MapReduce model .During Map phase ,grid was used to simplify data ,then representative information was sent to primary node .In Reduce phase ,outliers mining algorithm based on density was employed ,dense area was selected by the grid’s E .This algorithm was used to only calculate LOF of data in sparse area to reduce time complexity .Experimental results show that this algorithm is effective for mining outliers in data-intensive computing environments .
摘要:In recent years ,hyperbranched polyurethane (HBPU ) concrete sealing technology has come to use in different engineering fields .In this paper we introduced the HBPU sealing experi-ence in three aqueducts :Tonggu ,Heiwang and Zhaozhuang in Zibo Taihe reservoir ,the physico-chemical properties and construction technology of HBPU ,and the application of HBPU in old aq-ueduct sealing .It was agreed that HBPU concrete sealing technology has been put into use on many aqueduct sealing projects of water-saving irrigation and it was worth promoting .%结合混凝土嵌缝密封胶HBPU在淄博市太河水库总干渠渡槽中的止水施工经验,论述了HBPU的物理化学性能、施工工艺及HBPU在旧渡槽止水施工中的应用。实践表明,在灌区节水改造工程渡槽止水维修改造项目中应用 HBPU混凝土嵌缝密封胶具有很高的推广价值。
摘要:According to the urgency of stability on gypsum mine goaf ,this paper systemly intro-duces the classical theory research of domestic and foreign ,and static mumerical simulation analy-sis by using FLAC3D and ANSYS software .The dynamic evolution of stability on gypsum mine goaf respectively from rock rheological ,blasting disturbance and long-term strength is discussed . Research suggests ,that how to make dynamic evolution of rock influenced by disturbance ,rheo-logical in the roof-pillar-floor rock system w hich support goaf stability into the goaf stability anal-ysis ,establish a quantitative multi-factor coupling model ,dynamic failure criterion and dynamic failure mechanism for often stress state ,will be the key focus of the future research .%针对石膏矿采空区稳定性研究的紧迫性,系统介绍了国内外采空区稳定性经典理论,以及如何利用FLAC3D﹑ANSYS等软件进行静态数值模拟。论文着重从岩石流变﹑爆破扰动﹑长期强度等多因素动态演变方面对采空区稳定性进行探讨。研究讨论认为,如何将支撑采空区稳定的顶板-矿柱-底板体系中岩石受扰动、流变作用的动态演变纳入采空区稳定性分析中,建立量化多因素耦合模型和基于常应力状态的破坏准则及动态破坏机制,将成为未来研究的重点方向。
摘要:通过定义一个新的线性算子 Lp (a ,c),得到亚纯p-叶函数的一个新子类,并研究得到新子类的两个相关结论及一个推论。%By defining a new linear operator ,We get a new subclass of meromorphic p-leaf func-tion ,and get two related research conclusions and one corollary from it .
摘要:给出了所有Fq上码长为2nps的重根自对偶负循环码和F5上码长为10的重根自对偶负循环码的生成多项式。%In this paper ,we obtain all the self-dual repeated-root negacyclic codes of length 2nps over Fq ;generating polynomial of the self-dual repeated-root negacyclic codes of length 10 over F5 are derived .
摘要:利用闭合轨道理论,对原子在界面附近的自发辐射率的计算公式进行了推导,并对界面附近原子自发辐射率的多周期振荡现象进行了系统的研究。首先,根据光子的闭合轨道理论,把原子的自发辐射用经典的偶极天线辐射来模拟,推导出原子在一个金属界面旁的自发辐射率的计算公式,然后再推广到两个金属界面旁的原子自发辐射情况,并对原子自发辐射率的多周期振荡进行了分析。%We derived the formula of the spontaneous emission rate of atoms near the interfaces and discussed the multi-periodic oscillating phenomenon of the atoms near the interfaces .First of all ,according to the photon closed-orbit theory ,we simulated the spontaneous emission of atom near interface as the radiation of the classic dipole antenna ,then we derived the calculation for-mula of the spontaneous emission of atom near a metal surface .Next ,we developed this case to the spontaneous emission of atom near two metal surfaces ,and analyzed the multi-periodic oscil-lating phenomenon appeared in the spontaneous emission rate of atom near two metal surfaces .
摘要:The complex resistivity spectrums of two complex Cole-Cole models which are widely used in induced polarization method of frequency domain are comparatively analyzed in theory .It shows that at the same parameter values ,there is a big difference among the two complex resis-tivity amplitudes and phase spectrums . When the same kind of parameter changes in same a-mount ,the changes in phase spectrums are larger than those of amplitudes .When different pa-rameters increase or decrease ,the influences on the changes of quantity are different .It reveals the cause of the difference on the inversion results when use different kind models .It would pro-vide some references for exploring the more accurate polarization model and studying the mecha-nism of the induced polarization effect .%对两种在频率域激发极化法中广泛采用的复Cole-Cole模型复电阻率频谱进行了理论对比分析。在参数取值相同时,二者复电阻率幅值和相位频谱存在较大差异;在同类参数变化量相同的情况下,两种模型复电阻率的幅值和相位变化量的频谱也不相同,相位变化量的差异大于幅值变化量的差异;不同的参数增加或减少时,对变化量的影响也不一样。研究揭示了在进行反演时因为两种模型选择上的不同,对反演结果造成差异的原因,为更深入研究激发极化效应机理,探究一种统一准确的极化模型提供了理论基础。
摘要:Zero modal transient energy of single-phase to ground fault is used for the faulty line and the healthy line in non-effectively grounded system .The simulation model is established for electromagnetic transient program ATP .The zero modal transient energy can be obtained by de-signing Matlab program .Various factors ,such as different ground fault resistance ,fault distance , fault initial angle and intermittent fault ,should be put into overall consideration .T his paper gets the following conclusion :the sensitivity of detection method based on zero modal transient energy has high sensitivity .It is not only applicable to the isolated neutral system ,but also adaptable to peterson coil grounded system and intermittent fault .%为了提取小电流接地系统单相接地时故障线路和非故障线路的零模暂态能量值,利用电磁暂态程序A T P建立了仿真模型,借助M atlab程序设计得到了相应的零模暂态能量值。同时综合考虑不同接地过渡电阻、不同故障距离、不同故障初相角以及间歇性接地故障等多个因素,对小电流接地系统的单相接地故障进行了大量仿真。仿真分析结果表明:基于零模暂态能量的故障选线方法检测灵敏度高,不仅适用于中性点不接地系统,而且适用于中性点经消弧线圈接地系统及间歇性接地故障。
摘要:High speed ,deterministic and dual-redundancy are the technology features of avionics full duplex switched ethernet (AFDX) .According to the protocols of AFDX ,some key technol-ogies like plastic ,scheduling ,redundancy are broken through and a AFDX terminal system based on hierarchical priority queue algorithm is researched and designed .The system includes a net-work interface module and a network protocol stack part .A mathematical model based on the network calculus method is established to analyze the performance .The results indicated that the AFDX system can effectively guarantee the virtual link bandwidth and the quality of service .It can meet the requirements of the AFDX network sequence integrity with redundant fault-tolerant performance .So ,the design achieves the expected goals .%高速性、确定性、冗余度是航空电子双工交换以太网(A FDX )的技术特点。根据A FDX网络协议标准,突破整形、调度、冗余等关键技术,研究并设计了基于分层优先级队列算法的A FDX端系统。将端系统分为网络接口模块和网络协议栈两大部分进行设计,采用基于网络演算方法建立数学模型对其进行了性能分析。研究结果表明 A FDX端系统可以有效保证虚链路带宽和服务质量,满足A FDX网络的顺序完整性要求,具备冗余容错性能,实现了预期的主要设计指标。
摘要:将表面改性后的微米级二硫化钼添加至基础油中,利用M RS-10W型和M-2000型试验机,对所制备润滑油的摩擦学性能进行测定.结果表明,基础油中添加含量为1.5%的微米级二硫化钼后,润滑油的最大无卡咬载荷提高了15.5%,摩擦副之间的摩擦系数降低了33.1%,磨损量减少了43.5%.%The surface modificated of micron grade molybdenum disulfide is added to the base oil , and the tribological properties of lubricating oil and preparation were determined using of MRS-10W type and M-2000 type testing machine .T he result is that w hen the base oil is added by 1 .5%micron grade molybdenum disulfide ,maximum oil non seizer load is increased by 15 .5% ,the co-efficient of friction between the friction is reduced by 33 .1% ,and the wear volume reduced by 43 .5% .
摘要:Five kinds of polyolefin resins were used as matrix ,the continuous glass fiber rein-forced polyolefin prepreg tapes were prepared by a self-designed impregnation mold and the prepreg tapes were pressed into the corresponding plate using a hot stamping press .The influ-ences of five kinds of polyolefin ,fiber content and fiber distribution on mechanical properties of composites were studied .The results show that the tensile and flexural strengths increase obvi-ously with the addition of the glass fibers ,and the influence of fiber distribution on flexural prop-erty of the composites was more obviously than that of other property .In the range of 0~70% , the mechanical properties of the composites increased with the increase of the fiber content .In the range of 70% ~75% ,the mechanical properties of the composites decreased with the increase of the fiber content .The result of dynamic mechanical behavior shows that the deformation re-sistance of the composites enhanced evidently with the increase of the glass fiber content .%分别以五种聚烯烃树脂为基体,采用自行设计的浸渍模具制备了连续玻璃纤维增强聚烯烃预浸带,并采用热模压机将预浸带压制成相应的板材。研究了五种基体树脂、纤维含量、纤维分布对复合材料力学性能的影响。结果表明,加入玻纤后复合材料的拉伸强度、弯曲强度大幅度提高,纤维分布对材料的弯曲性能影响较大;纤维含量0~70%范围内,随纤维用量的增加,复合材料的力学性能提高;在70%~75%范围内,复合材料的力学性能随纤维含量的增加而降低。动态力学分析表明,加入纤维后明显提高了复合材料的抗形变能力。
摘要:目前四色定理的证明还没有简短的数学推理方法,必须借助于计算机才能够完成。在没有借助计算机的情况下,基于极大平面图的性质,通过结点合并的方式,研究了四色定理的证明方法,为该定理的进一步证明提供了重要参考。%Now ,the proof of the four color theorem must be completed with the aid of computer . There is no brief proof of the theorem .Based on the nature of maximal planar graph ,the paper analyses the theorem through merging some nodes ,and discusses proof method without the aid of computer .It provides an important reference for the further proof of the theorem .
摘要:Fe3 O4 ,β-FeOOH and α-Fe2 O3 were used as the precursor for the preparation of iron oxide/silica core-shell structures by Stober method .The effects of the precursors ,the concentra-tion of TEOS and ammonia on the coating process of silica were investigated .With the increasing ammonia and T EOS concentration ,the silica layer thickness increased and became uniform .T he samples were characterized by scanning electron microscopy (SEM ) ,transmission electron mi-croscopy (TEM ) ,and infrared spectrum (IR) .The results showed that β-FeOOH was better than the other two precursors because its OH led to the formation of uniform silica layer .%分别以Fe3 O4、β-FeOOH、和α-Fe2 O3作为前驱物,采用Stober水解法制备了氧化铁/氧化硅核壳结构,研究了前驱物种类和原料用量对二氧化硅包覆过程的影响。随着氨水和 T EOS用量的增加,包覆层厚度增加,包覆更加均匀。对样品进行了扫描电镜(SEM )、透射电镜(T EM )和红外光谱(IR)表征。实验结果表明,在三种类型的前驱物中,二氧化硅在β-FeOO H表面包覆最均匀,包覆效果最好。
摘要:考虑带有变利息力满足Stoodley模型的复合Poisson风险模型连续时间最终破产概率的上界,推导出了Stoodley变利息力下现值风险模型的表达形式及其性质;通过鞅方法给出了最终破产概率的Lundberg型指数上界。%In this paper ,we consider the upper bounds for ultimate ruin probabilities in continu-ous time in a compound Poisson model with variable interest force in Stoodley model .Presenta-tion and properties of discounted value risk model with Stoodley interest are derived .The Lund-berg upper bounds for discount risk model are also given by martingale methods .
摘要:一致可微是分析学中的重点与难点,以往学界多从一维情形讨论其充要条件,文章将其推广到高维情形,证明了映射一致可微当且仅当映射的微分算子即矩阵算子在算子范数的意义下一致连续;同时给出判定矩阵算子一致连续的充要条件,即矩阵算子里的每一个元素一致连续。在此基础上,进一步考虑无穷维空间的一致可微,证明了当映射在紧集的ε0-邻域上C1时,则映射在紧集的δ1(< kε0)邻域上一致可微。%It is important and difficult to study the concept of uniform differentiability in analysis . The sufficient and necessary condition for it is usually discussed in the one-dimension .In this pa-per ,we extended to the high-dimension ,and showed that the mapping is uniform differential if and only if the differential operator (i .e .,the matrix operator ) of mapping is uniform continuous in the sense of operator norm .Meanwhile ,we also gave a equivalent condition for judging the u-niform continuous to matrix operator ,i .e .,every element of matrix is uniform continuous .Fur-thermore ,we considered it in infinite dimensional ,and proved that if the mapping is C1 in ε0 -neighborhood of compact set ,it will be uniform differential in a δ1 (<ε0 )-neighborhood .