模型

As an often used physical model with good theoretical and practical values, StreeterPhelps model has been widely used to study water quality. However, in some special water areas the utilitization of StreeterPhelps model has some limitation as confirming reaeration coefficient often comes from tests in rivers with fast water flow speed with no consideration of wave effects. Furthermore, in practical research in Three Gorges Reservoir, the changing rule of COD appears abnormally. In some water areas far from pollution source, the value of COD changes with time, but does not follow the exponential attenuation rule. This phenomenon can not be explained by former modified StreeterPhelps model.

StreeterPhelps模型是目前进行河流水质研究常用的物理模型，具有良好的理论和实用价值，然而在某些特定水域，该模型的应用受到限制，主要原因是复氧系数的取定多在水流速度较大情况下得到的，而未考虑水面波动对复氧系数的影响，另外，在实际研究过程中发现三峡库区COD变化的规律出现异常：在离排污口相当远的水域，COD随时间变化趋势并不是指数衰减，而是在某个常值附近微小摆动，以往很多修正过的StreeterPhelps模型都无法解释这个现象。

However, in some special water areas the utilitization of StreeterPhelps model has some limitation as confirming reaeration coefficient often comes from tests in rivers with fast water flow speed with no consideration of wave effects. Furthermore, in practical research in Three Gorges Reservoir, the changing rule of COD appears abnormally. In some water areas far from pollution source, the value of COD changes with time, but does not follow the exponential attenuation rule. This phenomenon can not be explained by former modified StreeterPhelps model.

StreeterPhelps模型是目前进行河流水质研究常用的物理模型，具有良好的理论和实用价值，然而在某些特定水域，该模型的应用受到限制，主要原因是复氧系数的取定多在水流速度较大情况下得到的，而未考虑水面波动对复氧系数的影响，另外，在实际研究过程中发现三峡库区COD变化的规律出现异常：在离排污口相当远的水域，COD随时间变化趋势并不是指数衰减，而是在某个常值附近微小摆动，以往很多修正过的StreeterPhelps模型都无法解释这个现象。

To prepare studying hierarchical intelligent control system of material flows in mineral processing plant further, picturing, transition rulers, analytic methods, relevance matrix and dynamic equation, defect in applying of Petri network, fall short of orient object models applying are discussed after technology of formalization model built, non-formalization built and compound model. And Petri network system with time attribute is expanded opening network system with interface of input and output. The network system expanded with all attributes of basic Petri network model has hierarchy and recursiveness, can be analyzed with mathematical tools of network system and can deal with concurrent and asynchronously also.

为了对选矿厂生产物流递阶智能控制系统的进一步研究奠定基础，本文在讨论了形式化建模技术、非形式化建模技术和复合模型的基础上，研究和分析了Petri网的图形表示、变迁规则、分析方法、关联矩阵与动态方程、Petri网模型应用中的缺陷、面向对象模型应用中的不足，并把采用赋时的Petri网系统扩展成为对外界有输入和输出接口的开放网系统，扩展后的Petri网具有递阶性和递归性，同时保持基本Petri网的所有性质，使模型仍可采用网系统数学工具进行分析，并可处理生产物流系统中的并发性和异步性。

The application models of science communication include deficit models, democracy model, and reflexivity model.

科学传播应用模型有欠缺模型、民主模型和内省模型等形式。

Computer aid cotton field nutrients regionalize management based on nutrients spatial interpolating and fertilizer recommendation system based on GIS were studied.

以新疆生产建设兵团芳草湖农场、新湖农场和81、89团为基地，通过多点分散肥料试验建立了综合施肥模型并对几种施肥模型和模型参数进行了研究；应用反射仪测定棉株硝酸盐含量，建立了棉花快速营养诊断追肥指标；应用农田养分分析数据和相关农业技术资料，建立了芳草湖农场GIS数据库；建立了基于GIS、以综合施肥模型为核心的棉田养分分区管理和推荐施肥系统。

Nonlinear regressor model,quadratic blending model and radial basis functionneural network model were employed to describe the steady-state behavior of the gasoline blending process ,and the least squares algorithm was utilized to identify parameters in these models.

采用非线性回归模型、二次型调合模型以及基于RBF神经网络的并联模型等多种模型，对汽油调合过程的稳态特性进行建模与参数辨识。

Through the study of the trends of development of modern Western science methodology, the paper analyses the main features of three methodological models: prestippositionalist model of logics , relativist model of history and integrated model of logics and history.

本文以马克思主义观点审视现代西方科学方法论的演变趋势，揭示了现代西方科学方法论三大模型——预设主义的逻辑模型、相对主义的历史模型以及逻辑与历史相结合模型——的主要特征，并对西方各派方法论的成就与兴衰的缘由，作出了理论的概括和系统的评估。

The database consists of sample monitoring data,relief map data and metadata.

模型系统包含单因子评价模型、综合评价模型和空间插值模型。

Workflow process model consists of logic layer and semantics layer, and workflow pattern is the summarization and generalization of all the repetitiously used conjunctive symbols and its conjunctive relationship in the logic layer of a workflow process model.

本文在考察和比较了国内外各种关于工作流建模理论研究的基础上，针对实现工作流管理系统这一目标所涉及的工作流元模型、工作流过程模型等几个核心问题，在前人研究成果的基础上，对工作流元模型的可扩展性、工作流过程模型建模中存在的问题以及工作流管理系统的实现等方面开展了深入的研究工作。

In light of the analysis of the traditional methods of model representation and model composite, a novel theory of model representation and model composite based on Agent technology was proposed.

在分析当前模型表示与模型复合方法的局限性基础上，结合Agent技术，提出了基于Agent的模型表示与模型复合理论。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。