陈独秀早期教育思想三题

创建中国共产党之前,陈独秀的主要社会职业是教员。在其长达十六、七年的教育生涯中,陈独秀锐意改革,向传统的教育制度、观念和积习发起猛攻。他在诸多著述中,从教育方针、教育内容和教育方法等方面提出了许多深刻的教育思想和改革主张。这些观点,不但在当时是新颖而又锐利的,在今天也有时代意义和借鉴价值。     

栀子幼苗对土壤Pb的吸收及生理生长变化

通过实验方法测定了土壤Pb含量对栀子幼苗生长量和生理特性的影响,以及栀子幼苗对土壤Pb吸收富集特征.结果表明,随土壤Pb含量升高,栀子幼苗生物量、株高、叶绿素和可溶性糖含量降低;SOD、POD、CAT活性和MDA含量随土壤Pb含量的升高而升高.统计分析表明,各实验组间存在显著差异,当土壤Pb含量高于1045mg/kg,差异达极显著水平,栀子幼苗生物量与幼苗生理指标存在显著相关性;栀子幼苗根、茎、叶中对Pb的富集随土壤Pb含量升高而增加,栀子根是土壤Pb最主要的吸收部位.土壤Pb含量在1045 mg/kg以下,栀子幼苗能够正常生长生存;当土壤Pb含量高于1045mg/kg,栀子幼苗自身调节抵抗能力降低,其生理反应和生长均受到抑制.     

任务驱动项目导向教学模式的应用——以《网站规划与设计》课程为例

本文以《网站规划与设计》课程为例,对任务驱动项目导向教学模式的应用进行了探讨,并给出实践效果和注意事项。     

Time domain system identification of unknown initial conditions

System identification is a method for using measured data to create or improve a mathematical model of the object being tested. From the measured data however, noise is noticed at the beginning of the response. One solution to avoid this noise problem is to skip the noisy data and then use the initial conditions as active parameters, to be found by using the system identification process. This paper describes the development of the equations for setting up the initial conditions as active parameters. The simulated data and response data from actual shear buildings were used to prove the accuracy of both the algorithm and the computer program, which include the initial conditions as active parameters. The numerical and experimental model analysis showed that the value of mass, stiffness and frequency were very reasonable and that the computed acceleration and measured acceleration matched very well.     

Analysis modeling for plate buckling load of vibration test

In view of the recent technological development, the pursuit of safe high-precision structural designs has been the goal of most structural designers. To bridge the gap between the construction theories and the actual construction techniques, safety factors are adopted for designing the strength loading of structural members. If safety factors are too conservative, the extra building materials necessary will result in high construction cost. Thus, there has been a tendency in the construction field to derive a precise buckling load analysis model of member in order to establish accurate safety factors. A numerical analysis model, using modal analysis to acquire the dynamic function calculated by dynamic parameter to get the buckling load of member, is proposed in this paper. The fixed and simple supports around the circular plate are analyzed by this proposed method. And then, the Monte Carlo method and the normal distribution method are used for random sampling and measuring errors of numerical simulati     

蒋廷黻史学成就概述

二十世纪三、四十年代的中国近代史研究同现实息息相关,受到各派政治力量的密切关注。蒋廷黻正是这一时期著名的外交家和历史学家,本文简要分析他对中国近代外交史开拓性的贡献和所著《中国近代史》一书基本内容、特点和对近代史学科建设的推动作用。     

Time domain system identification of unknown initial conditions

System identification is a method for using measured data to create or improve a mathematical model of the object being tested. From the measured data however, noise is noticed at the beginning of the response. One solution to avoid this noise problem is to skip the noisy data and then use the initial conditions as active parameters, to be found by using the system identification process. This paper describes the development of the equations for setting up the initial conditions as active parameters. The simulated data and response data from actual shear buildings were used to prove the accuracy of both the algorithm and the computer program, which include the initial conditions as active parameters. The numerical and experimental model analysis showed that the value of mass, stiffness and frequency were very reasonable and that the computed acceleration and measured acceleration matched very well.     

The critical loading for lateral buckling of continuous welded rail

INTRODUCTION The conventional design of rails uses steel clipboards and bolts to link rails, and avoids bucklingcaused by thermal expansion effect by mountingexpansion joints to solve axial restraint generated byseasonal or day-and-night temperature changes. Butthe discontinuity at the rail joints brings discomfortand noise to passengers when the train has suddenlystops or starts, during which train speed cannot beeffectively increased, rails are more easily damaged,and the cost of mainte…     

基于不同结构元素的地物边界提取对比实验研究

数学形态滤波中结构的大小和形状不同,处理遥感图像获得的效果也不同。为了更好地理解结构元素的大小和形状对图像边界提取效果的影响,通过实验对比法,从简单到复杂地进行了分析。实验结果表明,道路等规则条状地物适合用线形结构元素,房屋等规则或近似规则的建筑物适合用方形结构元素,各项异性不明显的高分影像适合用圆形结构元素;结构元素的尺寸越大,损失的细节就越大,但是能去除更大的噪声点。     

Method of effective evaluation for examination of chloride ion in concrete

INTRODUCTION For some unknown reasons, perhaps caused bysalt, chlorine ions usually exist in reinforced concreteconsisting of cement, water, aggregate and additionalmaterials, and steel bars. In the presence of water, thechlorine ion reacts with iron existing in concrete andsteel bars to form Fe(OH)2 and FeCl2. The chemicalreactions seriously corrodes the surface of steel barsand damage the concrete, causing gradual decrease ofthe concrete compression and increase of its porosity,…