查询词典 mathematical model

A new mathematical model is put forward numerically to simulate the wheel ovalization.. In the numerical simulation, the dynamic model of a half railway vehicle coupled with a tangent track is employed. Using the new numerical method investigates vehicle-track coupling system dynamic responses including lateral and vertical displacement of wheelsets and the vehicle, lateral and vertical vibration acceleration of the track at different phase angle of the two side wheels of the same wheelset, which are compared with that of the traditional model. The numerical results show that the discipline and frequency of dynamic responses are accordant, amplitude and phase of lateral dynamic responses are different. It is concluded the traditional track geometric irregularity excitation model does not simulate the effect of periodic wheels ovalization on vehicle-track coupling system dynamic behavior truly, the new model is more accurate and reasonable.

本文研究了车轮二阶周期性非圆化—椭圆化，建立了一个新的模拟车轮椭圆化的数学模型，结合车辆－轨道空间耦合动力学模型，计算了同一轮对左右车轮不同相位和车轮椭圆度下轮对和车体的横、垂向位移，钢轨横、垂向振动加速度，并与传统模型计算结果作了对比，分析表明两种模型的动力响应变化规律和频率一致，但横向动力响应幅值和相位均存在不同程度不可忽略的差异，因此传统的轨道几何不平顺激励模型不能真实模拟车轮的周期性椭圆化对车辆－轨道耦合动态行为的影响，而本文模型更能反映实际椭圆车轮与钢轨接触情形，计算方法准确而合理。

Firstly, the flood control regulation of TGP in Sep is computed based on the analyses on the inflow in Sep and Oct, and the risk and loss on the ahead impounding scheme is calculated and analyzed. Then, the storage level, power production and releasing discharge are achieved by computing on the electricity generation model through reservoir regulation graph. Thirdly, obstruction in channel is analyzed and the problem in the Chongqing reach is more serious in 175-145-155m scheme. The sediment aggrading process and distribution on different schemes is calculated by 1-D reservoir mathematical model. The navigation benefit is computed by navigation model. Based on above calculations, the impounding time is decided by the multi-purpose decision model, and evaluate by analytical hierarchy and balance layout model. A best impounding scheme is achieved to match the requirement of flood control electricity generation and navigation et al.

首先，在对宜昌站9、10月份来水分析的基础上，采用第2章建立的防洪优化调度子模型进行了三峡水库9月份防洪调度，分析了汛末提前不同天蓄水对防洪的影响，计算了汛末不同蓄水方案水库9月份的洪灾风险率和风险损失；接着，根据第2章建立的发电调度子模型进行了三峡水库发电调度计算，得出了不同蓄水方案下水库的坝前水位、发电量及下泄流量过程；然后，分析了175-145-155m方案下三峡水库的碍航问题，指出175-145-155m方案下重庆河段的碍航问题最为严重，通过进行不同蓄水方案下水库一维泥沙冲淤计算，得出了不同蓄水方案下库区淤积过程及分布，并通过航运调度子模型，计算了不同蓄水方案下水库的航运效益；最后，根据以上防洪、发电及航运调度计算的结果，运用第3章水沙多目标决策模型对水库的蓄水时间进行了多目标决策，并采用层次加权均衡规划模型对计算结果进行评价，得到一个能满足水库防洪、发电及航运各方面要求的最佳蓄水方案。

In order to study the aircraft taxiing characteristics, considering the aircraft's attitude and rotation, the aircraft landing gear system mathematical model is built including tire model, ole-pneumatic shock strut model, landing gear walking model and main wheel brake device model.

为了研究飞机地面滑跑特性，考虑到滑跑过程中飞机姿态和转动的影响，建立了飞机起落架系统的轮胎模型、空气油液缓冲模型、起落架走步模型和主机轮刹车装置模型。

Based on the energy sensing, there are cooperative spectrum detection algorithms such as AND model, OR model, counting model, double threshold model, likelihood ratio model, linear cooperation model, and Distributed Wireless Communications System model.

基于能量检测，协作频谱检测的算法主要有：与算法、或算法、计数算法、分区算法、似然比算法、线性加权算法和分布式无线通信系统算法。

Results: For CRF rats which made by fed with feedingstuff contains 0.75% of adenine for 4 weeks, the weight of model control group rats were lighter than that of Yi Shen Granule groups rats. The water wastage of Yi Shen Granule groups rats were less than that of model control group rats. Compared urine volume, the ejectable quantity of Na, K, Cl and proteinuria in 12 hours , the data of Yi Shen Granule groups rats were less than that of model control rats. The specific gravity of Yi Shen Granule groups rats was higher than that of model control rats. The numerical value of RBC, HGB, HCT, MCV, MCH in model control group was lower than that in Yi Shen Granule groups. The content of BUN and Cre in serum of model control groups rats were higher than that of Yi Shen Granule groups. The results of excretion test of phenolsulfonphthalein showed that the RPF of Yi Shen Granule groups rats was larger than that of model control group rats.

结果： 益肾颗粒可以使0.75%腺嘌呤饲喂法致大鼠慢性肾衰模型动物体重增长加快；给药后观察，给药组动物饮水量较少，12小时尿量、12小时钠、氯、尿蛋白排泄总量均显著低于模型组动物，尿液比重值较大；模型组动物的RBC、HGB、HCT、MCV、MCH等指标的数值较给药组动物的数值小；给药组动物血清中BUN和Cre的含量较低；给药组动物酚红排泄率均高于模型组动物；给药30天，处死各组动物，尸解观察，模型对照组动物肾脏呈灰白色，各给药组动物肾脏表面均出现不同程度的红、白相兼的颗粒状纹理，各组动物肾脏均肿大，切面可见不同程度的腺嘌呤结晶沉积。

Modify the model by FreeForm software and dissecte the model of haunch bone; import the 3D visible model of haunch bone into Ansys8.0 software. Add mechanics parameter to the haunch bone model, construct 3D finite element model of acetabulum. 2、On the base of common fracture line of acetabular posterior wall fracture in clinical cases, split the acetabular 3D finite element model according to 1/3, 2/3, 3/3 areas fractures of posterior wall after simplify setting, obtain four types of acetabular posterior wall fracture model(including normal condition of acetabulum).

按髋臼骨折Letournel分类标准并根据临床髋臼后壁骨折病例常见骨折线位置，进行简化设定，依次按后壁1／3，2／3，3／3面积骨折将髋臼三维有限元模型后壁进行拆分，获得三种髋臼后壁骨折状态的有限元模型；再模拟双足直立位对髋骨约束设定，分别对后壁正常及不同面积骨折状态模型进行加载，获取各模型应力分布图并记录臼顶负重区、髋臼前壁和剩余后壁在不同后壁骨折状态下应力分布大小及改变。

In this study, the following studies have been carried out(1)Test on a typical MR damper employed in this study was carried out, Neural network model based a direct model and a inverse model were established. The performance of the models were cpmpared with the Bingham model and the hyperbolic tangent model. Results show that ANN model can describe the mechanical behavior of MR damper perfectly as a nonparmetric model.

本文主要进行了以下三个方面的工作：(1)对一种典型的磁流变阻尼器进行了性能试验，利用实验实测数据建立了阻尼器的Bingham模型、双曲正切模型两种参数模型以及基于神经网络的正向和逆向模型，对三种计算模型进行了仿真分析，并与试验结果进行对比研究，结果表明，神经网络模型比两种参数模型能更好地模拟阻尼器的动态性能。

The TIB triphone model tying structure adaptation strategy uses the baseline acoustic model's triphone model tying result as the transcendental model clustering center, with the adaptation data alignment by the baseline acoustic model, re-estimate the TIB triphone model clustering center and model tying structure recursively under maximum likelihood principle.

以基本声学模型训练过程中的三音子模型聚类结果作为先验知识的聚类中心，依据基本声学模型对自适应语音库的分割，按照最大似然准则迭代地重估新的聚类中心和模型聚类结构。

UA of blood of group of model Ⅰ,Ⅱ is elevatory (P.01), and UA of serum of group of Ⅰ of model of; of above of tenability 48 H is in 6, 24, 36, 48 H all group of Ⅱ of prep above model, model Ⅱ group is in 24, 36, group of Ⅲ of model of 48 H prep above (value of UA of serum of group of Ⅲ of model of P.05,.01); is in after building a model 6, 12, 24, 36 H apparent prep above contrasts group (P.01), it is normal that 48 H restores to come.

模型Ⅰ、Ⅱ组血UA升高(P.01)，且可维持48 h以上；模型Ⅰ组血清UA在6、24、36、48 h均高于模型Ⅱ组，模型Ⅱ组在24、36、48 h高于模型Ⅲ组(P.05、。01)；模型Ⅲ组血清UA值在造模后6、12、24、36 h明显高于对照组(P.01)，48 h恢复至正常。

After reviewed the process of Mitsubishi Corporation's business model change, this thesis analyze the trend and evolution of its business model from the view of value chain and business structure and then summarized three value chain model of total solution business model: core business expansion model, vertical and horizontal development model and research and development model.

本文在对三菱商事株式会社的商业模式的变革过程进行系统地回顾后，进而从价值链和业务结构的角度对其商业模式的演变和趋势进行了进一步分析。

But GST= 0.156, Nm=1. 588. As a result, the foundation of Youyongchi Avicennia marina population was the result of the migration of hypocotyles and human factors.

这项工作可以为海岸防护林中新引进种类的判定以及为研究种群建立者效应方法的确定提供科学依据。

The two-dimensional CDRC-ADI-FDTD update equations for collision unmagnetized plasma are induced. The unconditional stability of the CDRC-ADI-FDTD formulation for collision unmagnetized plasma is obtained by the examples.

推导了碰撞非磁化等离子体中的二维CDRC-ADI-FDTD迭代公式，并用算例验证了碰撞非磁化等离子体CDRC-ADI-FDTD算法也是无条件稳定的。