River system is an open system integrating various elements such as economy , society and entironment , in which substance and energy have direct or indirect exchanges through the activities concerned with water and thus there is evolution in different ways 摘要河流系统是一个经济社会、自然资源、生态环境相互耦合的开放系统，它通过水事活动直接或间接地与外界进行物质与能量交换，促使系统形成不同时空演化格局。
If the initial photon state is a fock state , the probability density of the electron exhibits bifurcation and confluence and the corresponding photon distribution is a time - periodic function which result from the energy exchange between the electron and field Ck态时，随着时间的演化，电子的儿率密度呈现分叉现象，相应的光子数分布是时间周期函数，这是由于电子与光场之间有能量交换。在这种情况下，系统是封闭的。
In the model , many processes or phenomena such as crack friction and growth , heat conduction , phase transformation of oxidant particulates , heat generation by viscous liquid layer , chemical reactions of gases in cracks , heat and mass exchange between phases of gas and solid , are described 模型描述了裂纹滑移扩展、热传导、含能颗粒相变、液化层粘性加热、裂纹内气相反应、气相固相质量能量交换及与裂纹扩展耦合等过程。
Three temperature equations include disconnected thermal conductivity coefficient and energy exchange terms between electron and ion , electron and photon , which are affected by the density an d temperature of the plasma , and by the atom parameter . implicit scheme have to be used to solve them . we use entirety linear iteration method to do this work 三温方程含有间断的热传导系数，存在着电子与光子、电子与离子的能量交换，这些量与离子的密度、温度和原子物理参数有关，对它们的求解必须采用隐式格式，我们采用整体线性化迭代格式迭代求解。
The frequencies of translational actuation influence the stability of the tethered mass system . when the frequencies approach the natural frequency of the system , the period of energy exchange decreases and the amplitude of the pendulum increase . when the frequencies equal to the natural frequency of the system , resonance appears 变幅激励的频率对系统稳定性有较大影响,当变幅激励频率接近系统固有频率时,系统面内外能量交换周期减小,摆幅增大;当变幅激励频率等于系统固有频率时,系统面内外均出现共振现象。
According to the industrial innovation system model set up in this thesis , the industrial innovation system is subject to affections of national resources , governmental policies , market situation , international economic and technical environment , corporate behaviors , operational conditions of sub - systems and other factors . there are energy exchange and feedback mechanism between sub - systems , between the industrial innovation system and outside environment . the industrial innovation is not completely a sub - system of the national innovation system 文中构建的产业创新系统模型说明，产业创新系统受国家有关资源、政府政策、市场状况、国际经济技术环境、企业行为、各子系统本身的运行状况等多种因素影响，存在系统内各子系统之间以及产业创新系统外在环境的能量交换和反馈机制；指出产业创新系统不完全是国家创新系统的子系统，它与国家创新系统有交叉关系，企业创新系统是产业创新系统的子系统，剖析了国家创新系统、产业创新系统和企业创新系统三者的区别与联系。
As to the simulation , three - dimensional n - s equations and two - phase flow model , in which the liquid toluene spray as discrete particles was considered , were employed to describe the turbulent combustion processes in the combustion chamber . the mass and energy transfer between the two phases were calculated by the droplet evaporation model , and the arrehnius model was used to obtain the gas chemical reaction rate . the details of 3d flow field , the distributions of temperature and compounds were obtained by solving the equations 数值仿真方面,应用三维湍流n - s方程以及颗粒轨道模型描述了激光器燃烧室内部的喷雾两相燃烧流动过程,两相之间的质量、能量交换由液滴蒸发模型计算,气相化学反应速率由arrhnius公式计算,通过耦合求解气液两相模型方程,模拟了燃烧室三维流场,得到了燃烧室内的温度和组分浓度分布。
The heat - exchange apparatus is the window for air - conditioner to exchange energy with outside . we analyze the efficiency of heat - exchange apparatus by the theory of heat - transmit , and compare the advantage and disadvantage of different type evaporator ' s and condenser ' s design by lots testing , and compare the effect of heat - exchange for different type flake , and compare the effect of heat resistance for different stretch of copper tube and flake . then we get many useful results from those different comparing 蒸发器与冷凝器统称为换热器，换热器是空调器与外界进行能量交换窗口，利用传热学原理对换热器的效率进行分析，通过大量的试验比较不同的蒸发器，冷凝器设计方案的优劣；比较冷凝器使用不同片型对换热效果的影响；比较铜管与翅片的不同胀紧对热阻的影响，通过比较得出很多有用的结论。
