混沌时间序列最大Lyapunov指数的计算

考虑到已有的计算最大Lyapunov指数的方法具有结果不准确或计算烦难的不足，我们提出了计算最大Lyapunov指数的新方法。此方法先在虚假领域概念基础上确定最佳嵌入参数，然后根据最大Lyapunov指数的定义计算其值，这样，使得此方法在理论上可靠，实施容易，克服了已有方法的不足。最后的应用实例对此进行了验证。     

Scientific evaluation of some Ayurvedic preparations for correction of iron deficiency and anemia

A number of preparations are available in Ayurved for treatment of anemia and iron deficiency. This study was designed to evaluate efficacy of some of them. Six most commonly used Ayurvedic iron containing preparations (Navayasa Curna, Punarnavadi Mandura, Dhatri Lauha, Pradarantaka Lauha, Sarva-Juara-Hara Lauha and Vrihat Yakrdari Lauha) were given in a dose of 250 mg b.d. for 30 days to six groups of iron deficient anemic patients; each group consisting of 20 patients. A control group was given Allopathic preparation—Irex-12, (containing—ferrous fumarate, vitamin C, folic acid and vitamin B₁₂); 1 capsule daily for 30 days for comparison. All hematological and iron parameters were determined before and after completion of treatment. The results showed that there was statistically significant rise (p<0.001) in all of them—Hb, PCV, TRBC, MCV, MCH, MCHC and plasma iron, percent saturation and plasma ferritin. Total iron binding capacity decreased significantly (p<0.001). The response of most of Ayurvedic preparations was better than Allopathic preparation and there was no side effect as observed with iron salts The Hb regeneration rate was 0.10 g/dl/day for Allopathic preparation; while it was above this value for all Ayurvedic preparations exceptPradarantaka Lauha which was least effective.Sarva-Juara-Hara Lauha was the drug of choice as Hb regeneration with it was highest 0.16 g/dl/day. Upon analysis of Ayurvedic drugs, these results were found to be consistent and correlated with iron content of the preparation.     

Physical parameter sensitivity of system eigenvalues and physical model reduction

The identification of subsystems and/or components that is related to a given eigenvalue of the overall system is a challenging and important topic. The use of special structure of the system matrices obtained busing bond graphs can result in identifying subsystems and/or components that affect a given eigenvalue of an overall system. This paper, by making use of a set of theorems and definitions proposes an efficient procedure for this purpose. The basic procedure is based upon the calculation of sensitivity of eigenvalues. The so-called “effect” matrices are produced that indicates the relative importance of physical parameters on a selected eigenvalue. In addition to the relative importance, the effect matrix is used for an efficient physical model reduction procedure. Furthermore, reasons of different dynamic behavior of a system can be explained. Use of effect matrices also improves the physical model reduction method based on decomposition procedures. Three examples are given to illustrate the approach and its consequences.     

QCS003型液压实验台性能参数采集数显系统设计与实现

根据高职院校液压课程实验的教学需求,以QCS003型液压教学实验台为载体,开发设计了实验台性能参数采集数显控制系统。系统以智能巡检仪为技术平台,配合各类传感器,在线检测实验过程中的压力、流量、温度等参数并数字显示。本系统安全可靠、操作方便、采集性能参数准确,可用于一般设备性能参数自动检测系统中,具有一定的应用前景。     

土的结构性损伤与损伤模型问题探讨

阐述土的结构性变化与损伤的关系，指出软粘土的结构性损伤包括应力损伤和扰动损伤，并在e-log曲线上探讨峰值损伤应力的合理取值和扰动损伤的定量评价。介绍复合体损伤模型，基于软粘土结构性损伤的含义。重点引荐修正损伤变量演化函数式(5a)，并从复合体概念出发，对损伤参数的合理确定提出了探讨意见与建议。     

Between-School Variation in Students' Achievement,Motivation, Affect,and Learning Strategies: Results from 81 Countries for Planning Group-Randomized Trials in Education

To plan group-randomized trials where treatment conditions are assigned to schools, researchers need design parameters that provide information about between-school differences in outcomes as well as the amount of variance that can be explained by covariates at the student (L1) and school (L2) levels. Most previous research has offered these parameters for U.S. samples and for achievement as the outcome. This paper and the online supplementary materials provide design parameters for 81 countries in three broad outcome categories (achievement, affect and motivation, and learning strategies) for domain-general and domain-specific (mathematics, reading, and science) measures. Sociodemographic characteristics were used as covariates. Data from representative samples of 15-year-old students stemmed from five cycles of the Programme for International Student Assessment (PISA; total number of students/schools: 1,905,147/70,098). Between-school differences as well as the amount of variance explained at L1 and L2 varied widely across countries and educational outcomes, demonstrating the limited generalizability of design parameters across these dimensions. The use of the design parameters to plan group-randomized trials is illustrated.     

基于位移型Gurtin变分原理的非时间步参数时间有限元法

本文基于位移型Gurtin变分原理,对时间域进行离散时,采用具有非时间步参数的插值函数逼近广义节点位移,给出了一种新的计算弹性动力学初值问题的非时间步参数时间有限元法,这是一种无条件稳定的计算格式,通过算例,可知本文方法具有计算方法简便、实用和精度较高的特点。     

在普通铣床上镗阶梯孔的铣夹头设计

在机加工过程中经常遇到在普通机床上不好加工的一些表面，需要设计一些简单实用的工艺装备。本文介绍一种在普通铣床上加工阶梯孔专用夹头的设计方法。     

应用型地方院校金工实习铣工实训教学设计

金工实习是高校工科专业学生必修的一门实践基础课,该课程具有承上启下的作用,是工科专业学生提高实践动手能力的重要教学环节之一,也是后续专业课学习的基础,既提高了学生的动手能力,也为学生今后参加学科竞赛提供了技术支持。文章以金工实习铣工实训为例,详细介绍了金工实习铣工工艺及操作。     

增程式电动汽车动力系统参数匹配与研究

通过对增程式电动汽车（Extended Range Electric Vehicle, EREV）动力系统的参数进行匹配,提出运用动力电池组端电压与荷电状态（State of Charge, SOC）之间的对应关系来控制增程器的开关,提高电动汽车的续航能力,为EREV/EV的动力系统的设计提供参考。