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Chinese Journal of Aeronautics 2013年第1期26卷 209-216页

作者： Wang Chengpeng Li Fuguo Lu Hongya Yuan Zhanwei Chen Bo State Key Laboratory of Solidification Processing Northwestern Polytechnical University Department of Mechanical Engineering Tsinghua University

The elliptical cross-section spiral equal-channel extrusion （ECSEE） process is simulated by using Deform-3D finite element software. The ratio m of major-axis to minor-axis length for ellipse-cross-section, the torsion angle u, the round-ellipse cross-section transitional channel L1, the elliptical rotation cross-section transitional channel L2 and the ellipse-round cross-section transitional channel L3 are destined for the extrusion process parameters. The average effective strain eave on cross-section of blank, the deformation uniformity coefficient a and the value of maximum damage dmax are chosen to be the optimize indexes, and the virtual orthogonal experiment of L16 （45） is designed. The correlation degree of the process factors affecting eave, a and dmax is analyzed by the numerical simulation results using the weights and grey association model. The process parameters are optimized by introducing the grey situation decision theory and the ECSEE optimal combination of process parameters is obtained： u of 120 , m of 1.55, L1 of 7 mm, L2 of 10 mm, and L3 of 10 mm. Simulation and experimental results show that the material can be refined with the optimized structural parameters of die. Therefore, the optimization results are satisfactory.

关键词： Correlation degree Elliptical cross-section spiral equal-channel extrusion (ECSEE) grey theory Optimization Orthogonal design Simulation

Establishment of Neural Network Prediction Model for Terminative Temperature Based on grey theory in Hot Metal Pretreatment

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Journal of Iron and Steel Research International 2012年第6期19卷 25-29页

作者： ZHANGHui—ning XUAn-jun CUIJian HEDong—feng TIANNai——yuan StateKeyLaboratoryofAdvancedMetallurgy UniversityofScienceandTechnologyBeijingBeijing100083China； SchoolofMetallurgicalandEcologicalEngineering UniversityofScienceandTechnologyBeijingBeijing100083China NingboIronandSteelCoLtd Ningbo315000Zh@angChina

In order to improve the accuracy of model for terminative temperature in steelmaking, it is necessary to predict and control before decarburization. Thus, an optimization neural network model of terminative temperature in the process of dephosphorization by laying correlative degree weights to all input factors related was used. Then sim- ulation experiment of model newly established is conducted utilizing 210 data from a domestic steel plant. The results show that hit rate arrives at 56.45~~ when error is within plus or minus 5%, and the value is 100% when within ~10%. Comparing to the traditional neural network prediction model, the accuracy almost increases by 6. 839o//oo. Thus, the simulation prediction fits the real perfectly, which accounts for that neural network model for terminative tempera- ture based on grey theory can reflect accurately the practice in dephosphorization. Naturally, this method is effective and nraeticahle.

关键词： grey theory correlation degree dephosphorization terminative temperature neural network model

The evaluation of mine geology disasters based on fuzzy mathematics and grey theory

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Journal of Coal Science & Engineering(China) 2007年第4期13卷 480-483页

作者：吕大炜吴立荣李增学 Key Laboratory of Mine Disaster Prevention and Control Shandong University of Science ＆ Technology Qingdao 266510 China College of Geo-lnformation Science and Engineering Shandong University of Science and Technology Qingdao 266510 China

Mine geology disasters include mine water, mine solid waste, apron and slide, ground collapse sink and underground fracture, etc.. The subject was studied in many ways, and fuzzy mathematics was usually used. It may assure the result and distinguish the dangerous rank of different areas. But it has two defects： The first is the result is not very exact, especially the border; The second is it is short of quantity. Fuzzy mathematics and grey theory were used in order to solve the problem. Firstly, mathematical model was constructed by using grey theory, so as to evaluate and forecast the dangerous rank of mining geology disaster in different areas. Then different areas were analyzed and divided by fuzzy mathematics. By doing these, similitude rules are not only studied but also differences are discriminated. Through the practice it can be known that the result is more accurate than before.

关键词： mine geology disaster fuzzy mathematics grey theory Matlab weight

Prediction method of highway pavement rutting based on the grey theory

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Journal of Southeast University(English Edition) 2015年第3期31卷 396-400页

作者：周岚倪富健赵岩荆东南大学交通学院南京210096 东南大学土木工程学院南京210096

In order to make a scientific pavement maintenance decision, a grey-theory-based prediction methodological framework is proposed to predict pavement performance. Based on the field pavement rutting data,analysis of variance （ANOVA）was first used to study the influence of different factors on pavement rutting. Cluster analysis was then employed to investigate the rutting development *** on the clustering results,the grey theory was applied to build pavement rutting models for each cluster, which can effectively reduce the complexity of the predictive *** results show that axial load and asphalt binder type play important roles in rutting *** prediction model is capable of capturing the uncertainty in the pavement performance prediction process and can meet the requirements of highway pavement maintenance,and,therefore,has a wide application prospects.

关键词： prediction method grey theory cluster analysis analysis of variance pavement rutting

grey-theory based intrusion detection model

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Journal of Systems Engineering and Electronics 2006年第1期17卷 230-235页

作者： Qin Boping Zhou Xianwei Yang Jun Song Cunyi School of Information Engineering Univ. of Science and Technology Beijing Beijing 100083 P. R. China

To solve the problem that current intrusion detection model needs large-scale data in formulating the model in real-time use, an intrusion detection system model based on grey theory （GTIDS） is presented. grey theory has merits of fewer requirements on original data scale, less limitation of the distribution pattern and simpler algorithm in modeling. With these merits GTIDS constructs model according to partial time sequence for rapid detect on intrusive act in secure system. In this detection model rate of false drop and false retrieval are effectively reduced through twice modeling and repeated detect on target data. Furthermore, GTIDS framework and specific process of modeling algorithm are presented. The affectivity of GTIDS is proved through emulated experiments comparing snort and next-generation intrusion detection expert system （NIDES） in SRI international.

关键词： network security intrusion detection grey theory model.