稳恒及似稳电路中电磁能的传输

论述平行双导线中传输的电磁能也是在场中传输的．     

简析能量在稳恒电路中的传输与转化

在稳恒电路中 ,负载不断地吸收能量 .但导线中自由电子定向运动的速度是很小的 ,一般只有 10 -5 m/ s的数量级 ,因此 ,认为电源的能量是通过电流传到负载的看法是不符合事实的 .那么 ,能量是怎样由电源传输到负载的呢 ?1　能量的传输1.1　电源不直接向导线提供能量电磁运动的能量是定域在电磁场中 ,而不是定域在电荷和电流的载体上 ,同时 ,电磁能量还可以从场的某个区域向邻近区域传输 .这一特点可以用能流密度矢量 S=E×H来描述 .此关系式作为电磁场理论的基本内容是普遍适用的 ,我们可据此来分析稳恒电路中能量的传输问题 .在电源内部 ,…     

广域电力系统动态稳定性分析的时滞系统方法

电力系统的二次系统是保证系统稳定运行及电能质量的基本组成部分,而二次系统的性能受到采样及传输等环节中的时滞现象的影响.在构建广域电力系统模型的过程中考虑了二次系统具有时滞,提出了新的Lyapunov-Krasovskii泛函构造与解析方法,得到了稳定性判据.该判据有效地减少了结果的保守性.通过典型的单机-无穷大系统仿真...     

以稳打快

高三就是一个简单的生态圈,在这种生态圈中,互相竞争在所难免.保持一定的敏感度是必要的,但更为重要的是对自己价值的认同,对目标实现的不变坚持,从而在努力过程中,有意识地去排除各种杂音与干扰,高考生涯就像一场战斗,是一场不间断的,让人无喘息余地的追逐.     

稳中求胜

梁山智有吴用,道有公孙,武更是好汉如云。英雄如雨,却以宋江为首。蜀国谋赖孔明,勇让张飞,却以刘备为王,东木西金,南火北水,却以戊土居中。何也? 宋公明为人沉稳,刘备做事敦厚,戊土谦稳厚实,终脱颖而出,施展风采,各得其所,故曰:为人沉稳,稳中求胜,吉。     

DNA远距离电荷传输机制研究进展述论

分析了影响DNA电荷传输的因素,阐述了DNA中电荷传输的各种机制,认为DNA分子中任何一种构象都能形成多种电荷传输途径,条件的改变会导致DNA调节电荷传输的机制发生变化.     

基于DV的实时视频流传输系统的研究与改进性设计

对数字视频格式的视频流传输系统进行了研究。针对数字视频流实时传输系统应用中出现的问题,结合当前互联网的现状,从带宽分配不均、视频流不可靠传输、服务质量等方面,提出数字视频实时传输系统的改进模型。最后对数字视频实时传输应用前景进行了展望。     

部分相干平顶光束通过ABCD光学系统的传输特性

利用惠更斯-菲涅尔衍射积分公式导出了部分相干平顶高斯光束(PCFGB)通过ABCD光学系统的传输公式。进一步导出了PCFGB在自由空间中传输的光强分布公式和等效束宽传输公式,且进行了数值计算及分析,并和FMGB的传输特性作了比较。研究结果表明,PCFGB在自由空间中传输时,随着传输距离的增大,其光强分布的平顶部分不会消退,但是它的束宽快速增大而光强快速减小,这与FMGB的传输特性有很大不同。     

一种毫伏信号远程传送的电路

在毫伏信号远距离传输过程中,干扰通常是通过电源线和地线串入小信号电压传输系统引起信号传输的误差,在工业控制中甚至可能导致严重后果。因此,必须将模拟量转换为数字量,增强传输加强信号的抗干扰性,消除由共地和共电源线而串入的干扰信号。     

部分相干径向偏振光在自由空间中的传输

基于交叉谱密度函数的传输定律及相干与偏振的统一理论,研究了部分相干径向偏振光在自由空间中的传输。结果表明：由于相干诱导作用,部分相干径向偏振光在自由空间中传输时其光强与偏振度都发生了变化,传输过程中径向偏振光的光强由原来的空心逐渐变为平顶接着变为高斯型,而不同的相干度下光束的偏振度在传输过程中的变化情况不同。     

Evolutionary stable strategy

Every behaviourally responsive animal (including us) make decisions. These can be simple behavioural decisions such as where to feed, what to feed, how long to feed, decisions related to finding, choosing and competing for mates, or simply maintaining ones territory. All these are conflict situations between competing individuals, hence can be best understood using a game theory approach. Using some examples of classical games, we show how evolutionary game theory can help understand behavioural decisions of animals. Game theory (along with its cousin, optimality theory) continues to provide a strong conceptual and theoretical framework to ecologists for understanding the mechanisms by which species coexist.     

一种稳定的蓝色有机电致发光材料

In order to compare two kinds of blue electroluminescent materials,we have investigated two kinds of blue OLEDs with the similar structure ITO/CuPc/NPB/JBEM:perylene/Alq/Mg:Ag[device(J)] and ITO/CuPc/NPB/DPVBi:perylene/Alq/Mg:Ag[device(D)].The difference of luminance and efficiency was not obvious for the two devices,However,there was remarkable difference for their lifetime.The device(J) achieved longer half lifetime of 1035h at initial luminance of 100 cd/m^2,and that of device(D) was only255h,According to their energy level diagrams,the differentce of their stability may originate from different host materials in the two devices.It may be attributed to the better thermal stability of JBEM molecues than that of DPVBi.It is shown that JBEM may be a promising blue organic electroluminescent material with great stability.     

浅谈改革发展与稳定的关系

要想达到"尽力把握客观规律,统一全党的认识,联合全国各族人民,调动所有积极的因素,加快社会主义现代化的建设"的目标,就必须要处理好带有全局性的改革、发展与稳定的关系。本文介绍了改革、发展与稳定他们三者之间的关系,强调了三者的相辅相成以及指出了如何处理三者之间的关系,为今后的建设中国特色社会主义道路提供了有力的依据。     

稳定性二氧化氯的应用开发

论述了稳定性二氧化氯的优良特性、生产工艺及应用开发     

A stable image reconstruction algorithm for ECT

INTRODUCTION Electrical capacitance tomography (ECT) is based on measuring the variation in capacitance be- tween pairs of electrodes surrounding a subject, and reconstructing the distribution of dielectric properties in the sensing area using the measured data. For im- age reconstruction with ECT, the linear back-pro- jection (LBP) algorithm is the most popular (Xie et al., 1992). However, it can only produce qualitative im- ages. In many cases, it is necessary to provide quantitativ…     

固态的建筑与变革的教育--从北京十二中学新校区设计谈起

一个好的学校设计应该在满足当前教育需要的情况下,为将来教育的发展打下良好基础.在社会转型时期,变革的教育在大范围内代表的是普遍的教育理念的创新,在小范围内则会具体到某个学校发展特色教育的需求.对具体的学校建筑设计来说,一个学校当前的实际需要和其未来发展的需要同等重要.     

New Method for the Calculation of Stable Phase Diagrams

Computercalculationofphasediagramsbeganmorethan30yearsago.Aclearanddetailedreviewoftheearlyworksl'-'lwascontributedbyAnewton-Raphsoniterationtechniqueandthesimplexmethod,andpointedoutthatthemathematicaldeductionsofthelatterarelesscomplicated.Manynsaral'I.…     

卫星天线稳定跟踪平台的总体模块化设计

针对多种武器系统对稳定跟踪平台的要求,对两轴卫星天线稳定跟踪平台进行了研究与设计。分析了天线稳定跟踪的基本原理,给出了控制方案,完成了平台的模块化设计和工作流程设计,经实验,该平台具有较好的跟踪能力。     

Implementing the KiVa antibullying program: recognition of stable victims

Teachers do not always recognise students who are victimised by their peers. In this study, we examined the recognition of stable victims in 76 schools beginning to implement the KiVa antibullying programme. We focused on 348 victims (9–15 years) who reported victimisation at the pretest and still at wave 2, after five months of programme implementation. Only 24% of these stable victims received the attention of school personnel during the school year. Multilevel logistic regression analyses revealed that male victims were recognised more often than female victims, but only in elementary school level. Peer reputation as a victim, as well as telling an adult about one’s plight increased the likelihood of recognition by school personnel, whereas bullying others (in addition to being victimised) decreased it. The study emphasises the importance of encouraging school personnel to put more effort in reaching the victimised students.