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Methods The relationship of dynamic model′s input and output was analyzed and a basic structure of system identification model based on the principle of optimization in model reduction and the property of a function approximator to be composed of feed-forward networks was presented.

分析了控制系统动态模型的输入、输出关系，依据模型等效的最优化原理和神经网络任意逼近有限不连续函数的性质，提出神经网络辨识模型的基本结构。

M{rX*o0 OBJECTIVE: To investigate the effects of neuronal nitric oxide synthase inhibitor 7-nitroindazole (7-NI) on smoke inhalation pulmonary injury in rats. METHODS: Forty healthy male SD rats were randomly divided into three groups: control group (n=8), smoke inhalation model group (n=16) and 7-NI treatment group (n=16). After reproducing the smoke inhalation model, to the 7-NI treatment group rats 7-NI (20 mg/kg in 2 ml arachis oil) was administered by intraperitoneal injection, while in the control group and the model group, 2 ml arachis oil was administered by intraperitoneal injection.

探讨神经型一氧化氮合酶抑制剂7-硝基吲唑(7-NI)在烟雾吸入性肺损伤中的作用。40只SD雄性大鼠被随机分为正常对照组(n=8)、烟雾吸入性肺损伤模型组(n=16)和7-NI治疗组(n=16)，建立烟雾吸入性肺损伤模型。7-NI治疗组在致伤后立即腹腔注射7-NI 20 mg/kg(溶于2 ml花生油中)；正常对照组及模型组腹腔注射2 ml花生油。

Experimental synchronous rotor internal mixer and two kinds of 55L synchronous rotor internal mixer, consulted a number of published articles at home and abroad, then, for the first time, formed four kinds of physical model and the corresponding mathematical model which related to the mixed stock between the mixing chamber side and the top of the rotor wing, to the mixed stock between the two rotors and to the mixed stock at the various temperatures of the mixing chamber. And from the character of model, the author gave the relevant analytic solutions and finite element approximation arithmetic solutions during the experimental process of the synchronous rotor internal mixer.

因此，本文作者在XM—1.7实验用同步转子密炼机和两种50L同步转子密炼机上进行了大量的实验，并参阅国内外已发表的文献和资料，首次建立了同步转子密炼机混炼过程中，胶料在转子棱峰与密炼室壁之间、胶料在两同步转子之间和密炼室中混炼胶温度变化的四种物理模型及其相应的数学模型，并根据所建模型的特点，分别给出了相应的解析解或有限元数值解。

The results from confirmatory factor analysis indicated:(1) The structural model of children's early mathematical ability was reasonable and it had good structural validity. In detail, children's early mathematical ability was explained by number, arithmetic, measurement, space/geometry and pattern;(2) The structure of children b early mathematical ability was stable across different ages but the structural model was not consistent completely;(3) Boys' structural model was identical with that of girls'.

经验证性因素分析发现：(1)儿童早期数学认知能力的结构模型是合理的，可接受的，具有较好的构想效度，具体讲，数、计算、测量、空间／几何和模式认知能力五个维度共同解释著儿童早期的数学认知能力；(2)不同年龄儿童早期数学认知能力的结构具有稳定性，但是结构模型並不完全一致，某些项目的解释率有所不同；(3)男、女儿童早期数学认知能力的结构模型具有一致性。

Then the delay is used in circadian model. Using the delay as a argument, the distribution of the roots of the characteristic equation associated with the model under light is analyzed. Then the stable and Hopf bifurcation condition of the circadian model with delay is obtained.

然后，将时滞引入到昼夜节律系统模型后，以滞量为参数，讨论光照昼夜节律模型线性部分特征方程根的分布情况，得到该系统的稳定性和Hopf分支产生的条件。

Unfortunately, it has been shownthat these methods are not suitable to study about chemical bonds due to not involvingchemical bonds. In order to consider chemical bonds obviously, we have proposed an atom-bondelectronegativity equalization model on the basis of density-functionaltheory and electronegativity equalization principle. The main contents of our atom-bond electronegativity equalization model contain:(1)Considering the fact that there are varies of chemical bonds in molecules andpartitioning the molecular electron density as summations of atomic electron densitiesand chemical bond's electron densities, we obtained the basic equations of atom-bondelectronegativity equalization model: the expression of the total energy 〓, theexpression of the atom electronegativity 〓 and the expression of the bondelectronegativity 〓.

为了明确地考虑和处理分子中存在的化学键，以便能够更好地描述体系中的电荷分布进而准确地描述分子体系中的有关物理化学性质，尤其是与化学键有关的物理化学性质，我们在密度泛函理论和电负性均衡原理基础上提出了原子-键电负性均衡模型，原子-键电负性均衡模型的主要内容是：(1)考虑到分子体系中存在各种化学键这个事实，将分子空间看成是由原子区和化学键区组成的，将分子的单电子密度表达成为分子中各组成原子的单电子密度和各化学键的单电子密度的加和，从而得到了原子-键电负性均衡模型的基本方程：分子体系总能量〓和分子中原子电负性〓和化学键电负性〓表达式。

The common method, that all strong-correlation terms of the model are eliminated, can bring the loss in the engineering application, so the new method is proposed that the identified model reserves some correlation. The augmented matrix A is constructed by the outputΔW and the matrix S. The"determinating order based on ratio of determinant"is brought out to screen the strong-correlation terms in the structure identification. The latent root estimation is improved in screening the eigenvalues and eigenvectors. Thus the estimation precision is improved greatly.The consistence check of guidance instrument error coefficients of flight test and ground test is the purpose of flight experiment. The causes of inconsistency of the two models are analyzed. The hypothesis test of linear regression model based on F statistics is proposed to check the consistence.Finally, the instability of error coefficients is probably caused by the change of the flight environments, therefore, the relation between the error coefficients and flight environment is analyzed. The approach is presented to identify SINS guidance instrument error models and compensate the error in the segmented sections corresponding to the change of vertical acceleration of aircraft.

在结构辨识中，常用的方法由于将模型中的强相关项全部剔除而给工程应用带来损失，因此，本文提出了新的有益思想，即在保留一定相关性的基础上进行辨识：将输出向量ΔW与环境函数矩阵S构成增广矩阵A，然后采用"比定阶行列式"来剔除相关向量的方法，这样既可以尽可能多地保留了对落点影响大的强相关参数，又可以对落点影响小的强相关参数给予剔除；在参数估计中，改进了特征根估计中特征根和特征向量的筛选方法，提出"近零"准则，从而大大提高了参数估计的精度；再者，鉴于天地模型"一致性"检验是飞行试验和SINS制导工具误差系数分离的主要目的，因此，本文又深入分析了造成天地模型不一致的原因，提出了采用基于F统计的线性回归模型假设检验方法来进行捷联制导工具误差模型的天地"一致性"检验；最后，鉴于飞行环境剧烈变化可能会对惯性仪表误差系数稳定性带来一定的影响，因此本文深入地分析了SINS制导工具误差系数与外界环境的关系，提出了基于过载变化大小的分段辨识和分段实时补偿的算法。

Methods Using Grey model （ 1 : 1 ）, autoregression model, ARIMA model to fit the data of the incidence rate in our country from 1984 to 2006, and predict the incidence rate of malaria in later years.

探讨不同模型在疟疾发病预测中的应用，并预测疟疾在中国未来的发病趋势。

The soft-measuring technique is systemically described from the following aspects: auxiliary variable selection, data processing, soft-measuring model construction and model correction. Moreover, in order to solve the problem of measuring temperature of aluminum electrolytic cell, the importation electric power and blanking velocity are selected as auxiliary variable, then the temperature estimated value of the electrolytic cell is calculated. An autoregressive model with controlled item based on Modern Time Series Analysis method is established.

从辅助变量选择、数据处理、软测量模型建立和模型修正等方面系统地介绍了软测量技术；并针对铝电解槽温度高、腐蚀性强、温度难以直接测量的问题，选择电解槽的输入电功率和下料速度作为辅助变量，利用现代时间序列分析法建立了带受控项目的自回归数学模型，从而计算出电解槽的温度估计值。

It provided a basis for building more accurate dynamical model. 4. Based on AD250 articulated dump truck multi-rigid body dynamics model, flexiblemulti-body models of suspension components for which the deformations are relatively important were built using finite element method. Modified Craig–Bampton modal synthesis and flexible multi-body methods were applied to build rigid-flexible coupling multi-body model of the truck. Dynamic simulations with different road profiles were performed.

基于AD250铰接式自卸车多刚体动力学模型，应用修正的Craig–Bampton模态综合法，对车辆行驶过程中相对变形较大的悬架杆件进行模态分析，把生成的模态中性文件引入到多刚体模型中取代相应的刚体，建立了相对多刚体模型更符合工程实际的整车刚柔耦合多体动力学模型。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。