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Cellular automata modeling of pedestrian's crossing dynamics 被引量:6
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作者 张晋 王慧 李平 《Journal of Zhejiang University Science》 CSCD 2004年第7期835-840,共6页
Cellular automata modeling techniques and the characteristics of mixed traffic flow were used to derive the 2-dimensional model presented here for simulation of pedestrian’s crossing dynamics. A conception of “stop... Cellular automata modeling techniques and the characteristics of mixed traffic flow were used to derive the 2-dimensional model presented here for simulation of pedestrian’s crossing dynamics. A conception of “stop point” is introduced to deal with traffic obstacles and resolve conflicts among pedestrians or between pedestrians and the other vehicles on the crosswalk. The model can be easily extended, is very efficient for simulation of pedestrian’s crossing dy- namics, can be integrated into traffic simulation software, and has been proved feasible by simulation experiments. 展开更多
关键词 Cellular automata modeling Pedestrian’s crossing dynamics Traffic simulation
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Eigenvalue Modeling and Cross-Correlation Analysis for 6. 0- 6. 4 GHz MIMO Channel 被引量:1
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作者 Ji-Liang Zhang Yang Wang +2 位作者 Li-Qin Ding Xiao-Min Huang Nai-Tong Zhang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第5期1-5,共5页
In Multiple-Input Multiple-Output( MIMO) system, the number of positive channel matrix eigenvalues is directly related to system performance. In order to characterize and model channel matrix eigenvalues,channel measu... In Multiple-Input Multiple-Output( MIMO) system, the number of positive channel matrix eigenvalues is directly related to system performance. In order to characterize and model channel matrix eigenvalues,channel measurements at 6. 0- 6. 4GHz by using 4 × 4 MIMO structure were conducted in a typical classroom environment. Based on measured data, the eigenvalues were modeled as Log-Normal distributed random variables and parameterized. Furthermore, Cross-Correlation( CC) coefficients of eigenvalues were estimated. The measurement results show that,under both Light-Of-Sight( LOS) and NonLight-Of-Sight( NLOS) scenarios,eigenvalues are highly de-correlated so that CC can be ignored for eigenvalue model. 展开更多
关键词 MIMO channel modeling EIGENVALUE measurement cross-CORRELATION
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Modeling of Continuous Cross-flow Microfiltration Process in an Airlift External-loop Slurry Reactor 被引量:3
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作者 Zheng Bo Tang Xiaojin +1 位作者 Zhang Zhanzhu Zong Baoning 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2019年第1期117-122,共6页
New modified combination mathematical models including the pores blocking models and the cake layer models were developed to describe the continuous cross-flow microfiltration in an airlift external loop slurry reacto... New modified combination mathematical models including the pores blocking models and the cake layer models were developed to describe the continuous cross-flow microfiltration in an airlift external loop slurry reactor. The pores blocking models were created based on the standard blocking law and the intermediate blocking law, and then the cake layer models were developed based on the hydrodynamic theory in which the calculation method of porosity of cake layer was newly corrected. The Air-Water-FCC equilibrium catalysts cold model experiment was used to verify the relevant models.Results showed that the calculated values fitted well with experimental data with a relative error of less than 10%. 展开更多
关键词 AIRLIFT external-loop SLURRY reactor cross-FLOW MICROFILTRATION filtration resistance mathematical model
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Modeling Crash Risk at Rail-Highway Grade Crossings by Track Class
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作者 Soumya Sharma Srinivas S. Pulugurtha 《Journal of Transportation Technologies》 2019年第3期261-275,共15页
The Federal Railroad Administration (FRA)’s Web Based Accident Prediction System (WBAPS) is used by federal, state and local agencies to get a preliminary idea on safety at a rail-highway grade crossing. It is an int... The Federal Railroad Administration (FRA)’s Web Based Accident Prediction System (WBAPS) is used by federal, state and local agencies to get a preliminary idea on safety at a rail-highway grade crossing. It is an interactive and user-friendly tool used to make funding decisions. WBAPS is almost three decades old and involves a three-step approach making it difficult to interpret the contribution of the variables included in the model. It also does not directly account for regional/local developments and technological advancements pertaining to signals and signs implemented at rail-highway grade crossings. Further, characteristics of a rail-highway grade crossing vary by track class which is not explicitly considered by WBAPS. This research, therefore, examines and develops a method and models to estimate crashes at rail-highway grade crossings by track class using regional/local level data. The method and models developed for each track class as well as considering all track classes together are based on data for the state of North Carolina. Linear, as well as count models based on Poisson and Negative Binomial (NB) distributions, was tested for applicability. Negative binomial models were found to be the best fit for the data used in this research. Models for each track class have better goodness of fit statistics compared to the model considering data for all track classes together. This is primarily because traffic, design, and operational characteristics at rail-highway grade crossings are different for each track class. The findings from statistical models in this research are supported by model validation. 展开更多
关键词 Rail-Highway Grade crossING CRASH Risk modeling TRACK CLASS
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Modeling the Surface Cross-Contamination of <i>Salmonella</i>spp. on Ready-to-Eat Meat via Slicing Operation 被引量:1
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作者 Shiowshuh Sheen Cheng-An Hwang 《Food and Nutrition Sciences》 2011年第9期916-924,共9页
Salmonella spp. surface transfer patterns/models between ready-to-eat (RTE) deli meat and a typical meat slicer are presented. A five-strain cocktail of Salmonella spp. was inoculated directly onto the rim of a round ... Salmonella spp. surface transfer patterns/models between ready-to-eat (RTE) deli meat and a typical meat slicer are presented. A five-strain cocktail of Salmonella spp. was inoculated directly onto the rim of a round slicer blade at an initial level of ca. 4, 5, 6, 7 or 8 log CFU/blade (ca. 3, 4, 5, 6 or 7 log CFU/cm2 of the blade edge area). Thereafter, a RTE deli meat (ham) was sliced to a thickness of 1.5 - 2.0 mm. In another cross-contamination scenario, a clean blade was initially used to slice ham, which was pre-surface-inoculated with the Salmonella cocktail (ca. 2, 3, 4, 5, 6 or 7 log CFU/cm2 with a total area of 100 cm2), followed by slicing of an un-inoculated ham. The log CFU of Salmonella per ham slice was determined and empirical models were developed. The models, follow the decreasing Power law, predict the surface cross-contamination of Salmonella spp. (at any initial level) for sliced deli meat (ham) and will provide a useful tool in developing RTE meat risk assessments. Surface transfer patterns of three foodborne pathogens, i.e. Listeria monocytogenes, E. coli O157:H7 and Salmonella predicted by models are also presented. 展开更多
关键词 SALMONELLA SURFACE Transfer cross-CONTAMINATION modeling SLICING
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Undergraduate Experimental Teaching Platform for Intelligent Limb Rehabilitation Training Based on "Medical-Engineering Interdisciplinary Crossing"
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作者 Dongfang TU Yongming YANG +6 位作者 Yan YU Can WENG Shengwei YAO Wei ZHANG Pengyun DUAN Weiyu NI Wencui LIU 《Asian Agricultural Research》 2024年第12期47-51,共5页
In view of the key role of undergraduate experimental teaching reform in cultivating high-quality talents with both innovative spirit and practical ability,this paper deeply discusses multi-dimensional reform strategi... In view of the key role of undergraduate experimental teaching reform in cultivating high-quality talents with both innovative spirit and practical ability,this paper deeply discusses multi-dimensional reform strategies.Specifically,the teaching mode of"double teachers for every student"is innovatively introduced,and scientific research projects are deeply integrated into undergraduate experimental teaching,aiming at realizing the modern development of teaching content and the diversified expansion of teaching methods.By designing and applying the undergraduate experimental teaching platform for intelligent limb rehabilitation training based on the concept of"medical-engineering interdisciplinary crossing",it not only builds a bridge for students to contact cutting-edge scientific research and strengthen practical skills,but also provides valuable ideas and practical models for the innovation of undergraduate experimental teaching.In the future,with the continuous optimization and upgrading of platform functions,it is expected to provide students with a richer and richer learning experience and comprehensively promote students'overall quality. 展开更多
关键词 Undergraduate experimental teaching Reform Undergraduate experimental teaching platform for intelligent limb rehabilitation training medical-engineering interdisciplinary crossing
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Centrifuge modeling of PGD response of buried pipe 被引量:8
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作者 Michael O'Rourke Vikram Gadicherla Tarek Abdoun 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2005年第1期69-73,共5页
A new centrifuge based method for determining the response of continuous buried pipe to PGD is presented. The physical characteristics of the RPI's 100 g-ton geotechnical centrifuge and the current lifeline experi... A new centrifuge based method for determining the response of continuous buried pipe to PGD is presented. The physical characteristics of the RPI's 100 g-ton geotechnical centrifuge and the current lifeline experiment split-box are described: The split-box contains the model pipeline and surrounding soil and is manufactured such that half can be offset, in flight, simulating PGD. In addition, governing similitude relations which allow one to determine the physical characteristics, (diameter, wall thickness and material modulus of elasticity) of the model pipeline are presented. Finally, recorded strains induced in two buried pipes with prototype diameters of 0.63 m and 0.95 m (24 and 36 inch) subject to 0.6 and 2.0 meters (2 and 6 feet) of full scale fault offsets and presented and compared to corresponding FE results. 展开更多
关键词 EARTHQUAKES buried pipe permanent ground deformation centrifuge models fault crossings lifeline earthquake engineering
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Level crossing in a two-photon Jaynes-Cummings model 被引量:3
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作者 任学藻 丛红璐 +1 位作者 廖旭 黎雷 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期279-282,共4页
In this paper,the energy spectrum of the two-photon Jaynes-Cummings model(TPJCM) is calculated exactly in the non-rotating wave approximation(non-RWA),and we study the level-crossing problem by means of fidelity.A... In this paper,the energy spectrum of the two-photon Jaynes-Cummings model(TPJCM) is calculated exactly in the non-rotating wave approximation(non-RWA),and we study the level-crossing problem by means of fidelity.A narrow peak of the fidelity is observed at the level-crossing point,which does not appear at the avoided-crossing point.Therefore fidelity is perfectly suited for detecting the level-crossing point in the energy spectrum. 展开更多
关键词 level crossing FIDELITY two-photon Jaynes-Cummings model
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Fast coating analysis and modeling for RCS reduction of aircraft 被引量:2
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作者 Haotian ZENG Xunwang ZHAO +2 位作者 Qin SU Yu ZHANG Hao LI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第6期1481-1487,共7页
In order to fast analyze the aircraft Radar Cross Section(RCS) and accurately reduce it with Radar Absorbing Materials(RAM), a comprehensive analysis method based on Higher-Order Method of Moments(HOMOM), termed Local... In order to fast analyze the aircraft Radar Cross Section(RCS) and accurately reduce it with Radar Absorbing Materials(RAM), a comprehensive analysis method based on Higher-Order Method of Moments(HOMOM), termed Locally Coating Method(LCM), is proposed in this paper. There are two steps to fast analyze coatings for RCS reduction in this method: analyze the RCS of various parts before coating the aircraft;model a coating over the aircraft and analyze the wave absorbing effect of it. The aircraft RCS is calculated as a whole but analyzed in various parts by LCM, and thus the RCS contribution of different parts can be compared without disturbing the current continuity. A model expansion algorithm is also presented in LCM to model absorption coatings on specified aircraft parts for later stage RCS calculation of the coated aircraft. 展开更多
关键词 Coating modeling HIGHER-ORDER Method of Moments(HOMOM) RADAR Absorbing Materials(RAM) RADAR cross Section(RCS) STEALTH technology
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Analysis of Factors Influencing Insomnia and Construction of a Prediction Model:A Cross-sectional Survey on Rescuers 被引量:3
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作者 SAI Xiao Yong CHEN Qiao +3 位作者 LUO Ting Gang SUN Yuan Yuan SONG Yu Jian CHEN Juan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第7期502-509,共8页
Objective To determine the factors influencing insomnia and construct early insomnia warning tools for rescuers to informbest practices for early screening and intervention.Methods Cluster sampling was used to conduct... Objective To determine the factors influencing insomnia and construct early insomnia warning tools for rescuers to informbest practices for early screening and intervention.Methods Cluster sampling was used to conduct a cross-sectional survey of 1,133 rescuers from one unit in Beijing,China.Logistic regression modeling and R software were used to analyze insomniarelated factors and construct a PRISM model,respectively.Results The positive rate of insomnia among rescuers was 2.74%.Accounting for participants’age,education,systolic pressure,smoking,per capita family monthly income,psychological resilience,and cognitive emotion regulation,logistic regression analysis revealed that,compared with families with an average monthly income less than 3,000 yuan,the odds ratio(OR)values and the[95%confidence interval(CI)]for participants of the following categories were as follows:average monthly family income greater than 5,000 yuan:2.998(1.307–6.879),smoking:4.124(1.954–8.706),and psychological resilience:0.960(0.933–0.988).The ROC curve area of the PRISM model(AUC)=0.7650,specificity=0.7169,and sensitivity=0.7419.Conclusion Insomnia was related to the participants’per capita family monthly income,smoking habits,and psychological resilience on rescue workers.The PRISM model’s good diagnostic value advises its use to screen rescuer early sleep quality.Further,advisable interventions to optimize sleep quality and battle effectiveness include psychological resilience training and smoking cessation. 展开更多
关键词 Rescuers INSOMNIA Influencing factors cross sectional survey Prediction model
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Coordinate-Parametric Matrix Model Inspired Square-Conjoint Pattern in Cross Woven for Conventional Bamboo Mat 被引量:1
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作者 Ye Fu Liwen Deng +2 位作者 Jinbo Hu Ti Li Shanshan Chang 《Journal of Renewable Materials》 EI 2023年第12期4025-4038,共14页
In the study,it is proposed that a coordinate-parametric matrix model is performed to a square-conjoint pattern of cross woven(SCPCW)in the bamboo mat.The patterns of SCPCW are firstly detected according to the perspe... In the study,it is proposed that a coordinate-parametric matrix model is performed to a square-conjoint pattern of cross woven(SCPCW)in the bamboo mat.The patterns of SCPCW are firstly detected according to the perspective of configuration,which is divided into the basic-monomer shape and the basic combination shape.Secondly,the compositions of design patterns in SCPCW are analyzed to attain the trend of curve shape.Based on the coordinate-parametric matrix model,the specimens of SCPCW are subsequently accomplished to elaborate the woven logic of bamboo mats.The digital innovation of SCPCW,defined by a mathematical resolution,is implemented by the software of Grasshopper(GH),which plays a crucial role in capturing image information by the Image Sampler component.Successively,the weaving logic of coordinated matrix is referred to apply in the computing component of Grasshopper software.Finally,the computer simulation could demonstrate that the coordinate-parametric matrix model of SCPCWwould be realized to analyze the micro-weaving structure and overall weaving effect in the bamboo mat. 展开更多
关键词 cross woven configuration and composition coordinated parametrization weaving model
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Assessing the host genetic background effects on type 2 diabetes and obesity development in response to mixed–oral bacteria and high-fat diet using the collaborative cross mouse model 被引量:5
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作者 Luna Karkar Hanifa JAbu-Toamih Atamni +2 位作者 Asal Milhem Yael Houri-Haddad Fuad A.Iraqi 《Animal Models and Experimental Medicine》 CSCD 2020年第2期152-159,共8页
Background: Host genetic background and sex, play central roles in defining the pathogenesis of type 2 diabetes(T2 D), obesity and infectious diseases. Our previous studies demonstrated the utilization of genetically ... Background: Host genetic background and sex, play central roles in defining the pathogenesis of type 2 diabetes(T2 D), obesity and infectious diseases. Our previous studies demonstrated the utilization of genetically highly diverse inbred mouse lines, namely collaborative cross(CC), for dissecting host susceptibility for the development of T2 D and obesity, showing significant variations following high-fat(42% fat) diet(HFD). Here, we aimed to assessing the host genetic background and sex effects on T2 D and obesity development in response to oral-mixed bacterial infection and HFD using the CC lines.Materials and Methods: Study cohort consists of 97 mice from 2 CC lines(both sexes), maintained on either HFD or Standard diet(CHD) for 12 weeks. At week 5 a group of mice from each diet were infected with Porphyromonas gingivalis(Pg) and Fusobacterium nucleatum(Fn) bacteria(control groups without infection). Body weight(BW) and glucose tolerance ability were assessed at the end time point of the experiment.Results: The CC lines varied(P <.05) at their BW gain and glucose tolerance ability(with sex effect) in response to diets and/or infection, showing opposite responses despite sharing the same environmental conditions. The combination of diet and infection enhances BW accumulation for IL1912, while restraints it for IL72. As for glucose tolerance ability, only females(both lines) were deteriorated in response to infection.Conclusions: This study emphasizes the power of the CC mouse population for the characterization of host genetic makeup for defining the susceptibility of the individual to development of obesity and/or impaired glucose tolerance. 展开更多
关键词 collaborative cross(CC)mouse model high-fat diet(HFD) mixed oral bacteria(PG and Fn) OBESITY SEX-DIFFERENCES type 2 diabetes(T2D)
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A Study on The Multi-Antenna Geometrical Depolarization Channel Modeling 被引量:2
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作者 SUN Xuehong YANG Xiaoli +2 位作者 ZENG Zhimin ZHANG Cheng BAI Bing 《China Communications》 SCIE CSCD 2016年第3期105-114,共10页
The traditional geometrical depolarization model that single transmitter to single receiver provides a simple method of polarization channel modeling. It can obtain the geometrical depolarization effect of each path i... The traditional geometrical depolarization model that single transmitter to single receiver provides a simple method of polarization channel modeling. It can obtain the geometrical depolarization effect of each path if known the antenna configuration, the polarization field radiation pattern and the spatial distribution of scatters. With the development of communication technology, information transmission spectrum is more and more scarce. The original model provides only a single channel polarization state, so the information will be limited that the polarization state carries in the polarization modulation. The research is so significance that how to carries polarization modulation information by using multi-antenna polarization state. However, the present study shows that have no depolarization effect model for multi-antenna systems. In this paper, we propose a multi-antenna geometrical depolarization model. On the basis of a single antenna to calculate the depolarization effect of the model, and through simulation to analysis the main factors that influence the depolarization effect. This article provides a multi-antenna geometrical depolarization channel modeling that can applied to large-scale array antenna, and to some extent increase the speed of information transmission. 展开更多
关键词 large-scale array antenna multi-antenna channel modeling depolarization effect cross polarization discrimination
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Model-based cross section calculations on production of 43,34Sc,45Ti, 51Cr, 54Mn, and 55Fe radioisotopes
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作者 Mustafa Yigit 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第4期128-136,共9页
A cross section database on excitation functions of reactions produced by charged particles is essential for many areas of nuclear research. Particularly, accurate knowledge on nuclear cross sections for the cyclotron... A cross section database on excitation functions of reactions produced by charged particles is essential for many areas of nuclear research. Particularly, accurate knowledge on nuclear cross sections for the cyclotron production of radioisotopes is very important for nuclear medicine. In the present paper, the cross section calculations for the production of^(43),^(34)Sc,^(45)Ti,^(51)Cr,^(54)Mn, and^(55) Fe radioisotopes were carried out by the use of ALICE/ASH code using the Fermi gas model, Kataria Ramamurthy Fermi gas model, and superfluid nuclear model for nuclear level density. Thereby, these model calculations were compared with the available measured data. 展开更多
关键词 RADIOISOTOPE PRODUCTION Scandium-44 Chromium-51 SUPERFLUID nuclear model cross section
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Modeling and Analysis of Transitional Tube with Constant Sectional Area along Derivative Central Route 被引量:1
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作者 MENG Xiang-bao TONG Bao-guo +1 位作者 PAN Zi-jian LI Hai-xing 《Computer Aided Drafting,Design and Manufacturing》 2011年第2期19-24,共6页
Firstly, sample square-circular transition tube along straight central route was modeled on CATIA software. The parameters are as follows: let the tube length is L, and the constant cross section area is S, and S = ... Firstly, sample square-circular transition tube along straight central route was modeled on CATIA software. The parameters are as follows: let the tube length is L, and the constant cross section area is S, and S = πR^2 = a2, in which R stands for the circle radius on one end, and a the square side length on the other end; set up the coordinate system with OX axis on the central route in which the origin O is on centroid of the square end and assume the cross section size at x as the square shaped with all four comers filleted in radius r which is proportional to x, that is, the linear slope of r is R/L, thus, both values r and square side length ax can be attained on the constant cross section area assumption. Secondly, some sample polygonal-circular transition tubes along straight, circular and helical central route were implemented similarly. Thirdly, numerical analysis of stress and displacement of these tubes were carried out on MSC/PATRAN software which are important to the distribution of turbulent flow and the layout of these transitional tube structures. 展开更多
关键词 parametric modeling transitional tube constant cross section area finite element analysis CATIA application
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Validation method for simulation models with cross iteration
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作者 FANG Ke ZHAO Kaibin ZHOU Yuchen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第3期555-563,共9页
Cross iteration often exists in the computational process of the simulation models, especially for control models. There is a credibility defect tracing problem in the validation of models with cross iteration. In ord... Cross iteration often exists in the computational process of the simulation models, especially for control models. There is a credibility defect tracing problem in the validation of models with cross iteration. In order to resolve this problem, after the problem formulation, a validation theorem on the cross iteration is proposed, and the proof of the theorem is given under the cross iteration circumstance. Meanwhile, applying the proposed theorem, the credibility calculation algorithm is provided, and the solvent of the defect tracing is explained. Further, based on the validation theorem on the cross iteration, a validation method for simulation models with the cross iteration is proposed, which is illustrated by a flowchart step by step. Finally, a validation example of a sixdegree of freedom (DOF) flight vehicle model is provided, and the validation process is performed by using the validation method. The result analysis shows that the method is effective to obtain the credibility of the model and accomplish the defect tracing of the validation. 展开更多
关键词 VALIDATION METHOD simulation model cross ITERATION VALIDATION THEOREM VALIDATION EXAMPLE
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Research on Service Life Prediction Model of Concrete Structure of Sea-crossing Bridge 被引量:2
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作者 WANG C J ZHANG G Z +3 位作者 LIU K X TU L Q LI J H QIN M Q 《武汉理工大学学报》 CAS CSCD 北大核心 2010年第17期141-146,共6页
According to the chloride corrosion environment,service life prediction model of concrete structure of sea-crossing bridge was built using modified Fick's second law and the whole probability calculation method,wh... According to the chloride corrosion environment,service life prediction model of concrete structure of sea-crossing bridge was built using modified Fick's second law and the whole probability calculation method,which was suitable for China. Furthermore,a visual service life prediction program of concrete structure was developed by optimized Monte Carlo method. Meanwhile,Life 365 program was compared,indicating reliability of the prediction program. Finally,the validity of prediction model was verified in JinTang Bridge of Zhoushan Island Mainland Linkage Project. 展开更多
关键词 sea-crossing bridge concrete structure service life PREDICTION model verify
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A Dynamic Cross Contagion Model of Currency Crisis between Two Countries
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作者 Yirong Ying Xiangqing Zou +1 位作者 Ke Chen Yuyuan Tong 《Intelligent Information Management》 2011年第4期137-141,共5页
The contagion aspect of the currency crisis is an important research issue today.In this paper, we set up a dynamic differential model of currency crisis cross contagions between two countries by expanding generalized... The contagion aspect of the currency crisis is an important research issue today.In this paper, we set up a dynamic differential model of currency crisis cross contagions between two countries by expanding generalized logistics model, and analyze all kinds of possible equilibrium conditions. It is probably a new idea of studying currency crisis contagion mechanism. 展开更多
关键词 cross Contagion CURRENCY CRISIS DIFFERENTIAL DYNAMIC model
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Investigation of Knowledge Transfer Approaches to Improve the Acoustic Modeling of Vietnamese ASR System 被引量:5
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作者 Danyang Liu Ji Xu +1 位作者 Pengyuan Zhang Yonghong Yan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第5期1187-1195,共9页
It is well known that automatic speech recognition(ASR) is a resource consuming task. It takes sufficient amount of data to train a state-of-the-art deep neural network acoustic model. As for some low-resource languag... It is well known that automatic speech recognition(ASR) is a resource consuming task. It takes sufficient amount of data to train a state-of-the-art deep neural network acoustic model. As for some low-resource languages where scripted speech is difficult to obtain, data sparsity is the main problem that limits the performance of speech recognition system. In this paper, several knowledge transfer methods are investigated to overcome the data sparsity problem with the help of high-resource languages.The first one is a pre-training and fine-tuning(PT/FT) method, in which the parameters of hidden layers are initialized with a welltrained neural network. Secondly, the progressive neural networks(Prognets) are investigated. With the help of lateral connections in the network architecture, Prognets are immune to forgetting effect and superior in knowledge transferring. Finally,bottleneck features(BNF) are extracted using cross-lingual deep neural networks and serves as an enhanced feature to improve the performance of ASR system. Experiments are conducted in a low-resource Vietnamese dataset. The results show that all three methods yield significant gains over the baseline system, and the Prognets acoustic model performs the best. Further improvements can be obtained by combining the Prognets model and bottleneck features. 展开更多
关键词 BOTTLENECK feature (BNF) cross-lingual automatic speech recognition (ASR) PROGRESSIVE neural networks (Prognets) model transfer learning
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Spatial Pattern Induced by Cross-Diffusion in a Chemostat Model with Maintenance Energy 被引量:1
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作者 LIU Qingsheng PENG Yahong 《Journal of Donghua University(English Edition)》 EI CAS 2018年第6期469-472,共4页
A chemostat model with maintenance energy and crossdiffusion is considered,and the formation of patterns is caused by the cross-diffusion. First, through linear stability analysis, the necessary conditions for the for... A chemostat model with maintenance energy and crossdiffusion is considered,and the formation of patterns is caused by the cross-diffusion. First, through linear stability analysis, the necessary conditions for the formation of the spatial patterns are given. Then numerical simulations by changing the values of crossdiffusions in the unstable domain are performed. The results showthat the cross-diffusion coefficient plays an important role in the formation of the pattern, and the different values of the crossdiffusion coefficients may lead to different types of pattern formation. 展开更多
关键词 PATTERN FORMATION CHEMOSTAT model cross-DIFFUSION TURING INSTABILITY stability
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