BP神经网络在润滑油摩擦改进剂复配性研究中的应用

研制润滑油的关键问题之一是研究其中多种添加剂间的相互作用和添加剂间的最佳复配比.以正交试验设计为基础的直现分析和回归分析可以探讨添加剂间的相互作用,而基于上述方法的最佳复配比的计算往往误差较大.采用BP神经网络计算最佳复配比,并与前两种方法作比较,发现BP神经网络在计算最优复配比时,结论可靠,精度高,是研制最佳润滑油配方的优秀数学工具.     

BP神经网络在润滑油摩擦改进剂复配性研究中的应用

研制润滑油的关键问题之一是研究其中多种添加剂间的相互作用和添加剂间的最佳复配比。以正交试验设计为基础的直现分析和回归分析可以探讨添加剂间的相互作用，而基于上述方法的最佳复配比的计算往往误差较大。采用BP神经网络计算最佳复配比，并与前两种方法作比较，发现BP神经网络在计算最优复配比时，结论可靠，精度高，是研制最佳润滑油配方的优秀数学工具。     

小麦施肥决策知识库研究与实现

根据实际生产中普遍存在着肥料用量过多或过少,各种肥料配比不合适等问题,以小麦施肥决策系统领域专家的知识和经验为基础,有助于上述问题的解决。详细论述了如何使用专家系统和知识库技术实现小麦施肥决策知识库和推理机,并对用户所提交数据的有效性验证进行了分析讨论。系统可根据用户提供的基本数据进行土壤缺素和施肥量的决策。该知识库已经集成到山西省小麦专家系统中,经过示范区的生产实践已取得了成效。     

BP神经网络在专家系统开发中的研究与应用

针对专家系统开发过程中遇到的"知识瓶颈"问题,提出了神经网络与专家系统相结合的方法,利用神经网络训练和学习得到的故障数据来丰富专家系统的知识库,提高专家系统诊断的准确性。基于某型燃气轮机对此方法进行了验证,结果证明这种方法是可行的。     

用神经网络技术建造碳钢和低合金钢大气腐蚀知识库

简要介绍了传统专家系统知识库所存在的问题,提出了一个基于神经网络的碳钢和低合金钢大气腐蚀知识库系统,并着重阐述了这种新型知识库系统的知识获取、知识表示和系统的实现等问题.     

基于模糊Petri网的动态知识表示与推理方法

针对专家系统知识库中的知识具有模糊特性以及知识库需要频繁更新的特点,设计了一种基于模糊Petri网的动态知识表示与推理方法。该方法利用实际环境中的数据,通过学习来调整知识模型的权值、阈值和确信度等参数,从而实现知识库的动态实时更新。此方法同时结合了产生式知识表示方式和神经网络知识表示方式的优点:知识模型结构清晰,参数意义明确;具有学习和并行推理能力。仿真实验结果表明,经过训练调整后的知识模型具有更高的准确度。     

水闸老化评估神经网络专家系统知识获取方法

专家系统的工作过程是一个获得并应用知识的过程,恰当的知识表示对于专家系统的构建具有重要意义.以上海地区多座中小型水闸老化检测实例为基础,开发出水闸老化评估神经网络专家系统ESANN-SLUICE.此系统从实例中生成数据,再对神经网络进行训练和管理,从而建立权值矩阵,然后转换成相当规则的知识库,提供给专家系统使用.该方法是水闸老化评估知识获取的一种新方法,是对传统知识获取方式的拓展和补充.最后通过实例证明该方法是可行和有效的.     

基于神经网络的客车车身造型评价专家系统

阐述了利用人工神经网络(ANN)技术构建专家系统对客车车身造型进行评价的方法,从数据收集、图形的预处理、知识库的构建及神经网络模型的设计与训练等方面研究了准三维造型评价专家系统的关键技术问题.开发了客车造型评价专家系统软件,并通过实际客车造型任务,验证了所开发软件的有效性.     

基于BP神经网络的沼气工程故障诊断专家系统

针对传统专家系统的知识获取困难、推理能力差、智能水平低和实用性差等缺点,阐述了BP神经网络运用于农村沼气工程故障诊断专家系统的设计思想,应用专家系统与数据结构的有关知识和面向对象的设计方法,设计了农村沼气工程故障诊断专家系统知识库,提高了农村沼气工程故障诊断效率,为故障诊断专家系统的知识库设计提供科学有效的方法.     

一种雷达模拟电路故障诊断专家系统的设计

本文概述了专家系统的设计思想,详细介绍了专家系统在雷达模拟电路故障诊断中的实现方法、知识库建立、推理机建造、解释机制建立以及系统软件设计,并采用先进的VXI bus和神经网络为辅,弥补了专家系统的缺点,使系统具有高可靠性和扩展性。     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.