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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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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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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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Panel data models with cross-sectional dependence: a selective review 被引量:1
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作者 XU Qiu-hua CAI Zong-wu FANG Ying 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2016年第2期127-147,共21页
In this review, we highlight some recent methodological and theoretical develop- ments in estimation and testing of large panel data models with cross-sectional dependence. The paper begins with a discussion of issues... In this review, we highlight some recent methodological and theoretical develop- ments in estimation and testing of large panel data models with cross-sectional dependence. The paper begins with a discussion of issues of cross-sectional dependence, and introduces the concepts of weak and strong cross-sectional dependence. Then, the main attention is primarily paid to spatial and factor approaches for modeling cross-sectional dependence for both linear and nonlinear (nonparametric and semiparametric) panel data models. Finally, we conclude with some speculations on future research directions. 展开更多
关键词 Panel data models cross-sectional dependence Spatial dependence Interactive fixed effects Common factors.
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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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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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CROSS-RANGE RESOLUTION OF SYNTHETIC APERTURE RADAR BASED ON DIVING MODEL 被引量:1
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作者 Sun Bing Zhou Yinqing Chen Jie 《Journal of Electronics(China)》 2011年第1期71-76,共6页
This paper concentrates on the cross-range resolution of Synthetic Aperture Radar(SAR) based on diving model.In comparison to the azimuth resolution,the cross-range resolution can manifest the two-dimensional resoluti... This paper concentrates on the cross-range resolution of Synthetic Aperture Radar(SAR) based on diving model.In comparison to the azimuth resolution,the cross-range resolution can manifest the two-dimensional resolution ability of the imaging sensor SAR correctly.The diving model of SAR is an extended model from the conventional stripmap model,and the cross-range resolution expression is deduced from the equivalent linear frequency modulation pulses' compression.This expression points out that only the cross-range velocity component of the horizontal velocity contributes to the cross-range resolution.Also the cross-range resolution expressions and the performance of the conventional stripmap operation,squint side-look operation and beam circular-scanning operation are discussed.The cross-range resolution expression based on diving model will provide more general and more accurate reference. 展开更多
关键词 Synthetic Aperture Radar(SAR) cross-range resolution Diving model Velocity component
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Three-Dimensional Modelling of a DC Arc in Cross-Flow
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作者 黎林村 夏维东 +1 位作者 周鹤凌 马强 《Plasma Science and Technology》 SCIE EI CAS CSCD 2007年第5期564-569,共6页
A commercial CFD (computational fluid dynamics) code FLUENT was used and modified to model an atmospheric pressure argon arc in a low cross flow by solving the fully coupled conservation equations. Numerical experim... A commercial CFD (computational fluid dynamics) code FLUENT was used and modified to model an atmospheric pressure argon arc in a low cross flow by solving the fully coupled conservation equations. Numerical experiments, with an arc current of 100 A to 200 A, an arcing distance of 3 mm to 6 mm, and a cross-flow velocity of 10 m/s to 30 m/s, were carried out. The modelling results show that the arc tends to take the shortest path to the anode when deflected by the cross flow; its anode attachment is farther downstream than the cathode one. Furthermore, due to the low input gas flow imposed in this study, the effect of electromagnetic force is important and it influences the crosscut shape of the arc significantly. 展开更多
关键词 arc modelling cross-FLOW FLUENT
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A Novel Cross-Media Layered Semantic Mining Model 被引量:1
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作者 ZENG Cheng CAO Jiaheng +2 位作者 PENG Zhiyong WANG Ke WANG Hui 《Wuhan University Journal of Natural Sciences》 CAS 2008年第1期21-26,共6页
This paper presents a cross-media semantic mining model (CSMM) based on object semantic. This model obtains object-level semantic information in terms of maximum probability principle. Then semantic templates are tr... This paper presents a cross-media semantic mining model (CSMM) based on object semantic. This model obtains object-level semantic information in terms of maximum probability principle. Then semantic templates are trained and constructed with STTS (Semantic Template Training System), which are taken as the bridge to realize the transition from various low-level media feature to object semantic. Furthermore, we put forward a kind of double layers metadata structure to efficaciously store and manage mined low-level feature and high-level semantic. This model has broad application in lots of domains such as intelligent retrieval engine, medical diagnoses, multimedia design and so on. 展开更多
关键词 cross-media semantic mining model object semantic semantic template semantic template training system METADATA
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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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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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A New Perspective on the Demand of the Cross-cultural Audiences:Lacuna and Universal Model
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作者 Zhang Hang 《学术界》 CSSCI 北大核心 2016年第11期316-322,共7页
Lacuna and Universal Model provides a new terminology and classification for the factors behind the success and failure of cross-cultural media content,and thus forms an analysis framework for the study of the cross-c... Lacuna and Universal Model provides a new terminology and classification for the factors behind the success and failure of cross-cultural media content,and thus forms an analysis framework for the study of the cross-cultural audiences'need.According to this model,the audience will dislike or not select foreign media content under these circumstances:(1)audiences find that the content is irrelevant or unsuitable;(2)audiences cannot comprehend the content;3)they do not like the style of such content.This model also argues that cross-cultural media content is successfully spread under these circumstances:(1)the media content shows attractive attribute to cross-cultural audience;(2)the media content is open to alternative readings. 展开更多
关键词 外国媒体 跨文化受众 发展现状 文化研究
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Modeling of Continuous Cross-flow Microfiltration Process in an Airlift External-loop Slurry Reactor 被引量:2
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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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Reaction cross section studies of ^(12)C using the modified Glauber model in conjunction with nonlinear relativistic mean-field theory
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作者 FUKUDA Mitsunori FAN Guangwei +7 位作者 AN Zhendong CAI Xiaolu FAN Gongtao HUANG Bosong LI Yongjiang XU Benji YAN Zhe XU Wang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2012年第5期312-316,共5页
We studied the structure of 12 C through the modified Glauber model using the density distributions calculated by the relativistic mean field theory. The experimental reaction cross sections of 12 C + 12 C were analyz... We studied the structure of 12 C through the modified Glauber model using the density distributions calculated by the relativistic mean field theory. The experimental reaction cross sections of 12 C + 12 C were analyzed within the MOL by a χ 2 -fitting procedure. The effects of the nuclear deformation on the reaction cross sections are studied. The reliable structure of 12 C is deduced. The studies show that the conjunction of these two models will be a more effective tool to study the properties of nuclei. 展开更多
关键词 GLAUBER模型 相对论平均场理论 核反应总截面 非线性 密度分布 反应截面 拟合程序 截面变形
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Global existence of weak solutions to a prey-predator model with strong cross-diffusion
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作者 李慧玲 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第6期727-740,共14页
Using finite differences and entropy inequalities, the global existence of weak solutions to a multidimensional parabolic strongly coupled prey-predator model is obtained. The nonnegativity of the solutions is also sh... Using finite differences and entropy inequalities, the global existence of weak solutions to a multidimensional parabolic strongly coupled prey-predator model is obtained. The nonnegativity of the solutions is also shown. 展开更多
关键词 prey-predator model strong cross-diffusion entropy functional existenceof weak solutions Orlicz space
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Efficient protocols and methods for high-throughput utilization of the Collaborative Cross mouse model for dissecting the genetic basis of complex traits
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作者 Hanifa J.Abu-Toamih Atamni Fuad A.Iraqi 《Animal Models and Experimental Medicine》 CSCD 2019年第3期137-149,共13页
The Collaborative Cross(CC)mouse model is a next‐generation mouse genetic reference population(GRP)designated for a high‐resolution quantitative trait loci(QTL)mapping of complex traits during health and disease.The... The Collaborative Cross(CC)mouse model is a next‐generation mouse genetic reference population(GRP)designated for a high‐resolution quantitative trait loci(QTL)mapping of complex traits during health and disease.The CC lines were generated from reciprocal crosses of eight divergent mouse founder strains composed of five classical and three wild‐derived strains.Complex traits are defined to be controlled by variations within multiple genes and the gene/environment interactions.In this article,we introduce and present variety of protocols and results of studying the host response to infectious and chronic diseases,including type 2 diabetes and metabolic diseases,body composition,immune response,colorectal cancer,susceptibility to Aspergillus fumigatus,Klebsiella pneumoniae,Pseudomonas aeruginosa,sepsis,and mixed infections of Porphyromonas gingivalis and Fusobacterium nucleatum,which were conducted at our laboratory using the CC mouse population.These traits are observed at multiple levels of the body systems,including metabolism,body weight,immune profile,susceptibility or resistance to the development and progress of infectious or chronic diseases.Herein,we present full protocols and step‐by‐step methods,implemented in our laboratory for the phenotypic and genotypic characterization of the different CC lines,mapping the gene underlying the host response to these infections and chronic diseases.The CC mouse model is a unique and powerful GRP for dissecting the host genetic architectures underlying complex traits,including chronic and infectious diseases. 展开更多
关键词 COLLABORATIVE cross(CC)mouse model complex traits genetic reference population(GRP) infectious and chronic diseases quantitative TRAIT loci(QTL)
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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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Testing for Cross-Sectional Dependence in a RandomEffects Model
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作者 Afees Salisu Sam Olofin Eugene Kouassi 《Open Journal of Statistics》 2012年第1期88-97,共10页
This paper extends and generalizes the works of [1,2] to allow for cross-sectional dependence in the context of a two-way error components model and consequently develops LM test. The cross-sectional dependence follow... This paper extends and generalizes the works of [1,2] to allow for cross-sectional dependence in the context of a two-way error components model and consequently develops LM test. The cross-sectional dependence follows the first order spatial autoregressive error (SAE) process and is imposed on the remainder disturbances. It is important to note that this paper does not consider alternative forms of spatial lag dependence other than SAE. It also does not allow for endogeneity of the regressors and requires the normality assumption to derive the LM test. 展开更多
关键词 cross-SECTIONAL DEPENDENCE Error Components model LAGRANGIAN MULTIPLIER (LM) Tests
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Mechanisms of Proton-Proton Inelastic Cross-Section Growth in Multi-Peripheral Model within the Framework of Perturbation Theory. Part 2
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作者 Igor Sharf Andrii Tykhonov +3 位作者 Grygorii Sokhrannyi Maksym Deliyergiyev Natalia Podolyan Vitaliy Rusov 《Journal of Modern Physics》 2012年第1期16-27,共12页
We demonstrate a new technique for calculating proton-proton inelastic cross-section, which allows one by application of the Laplace' method replace the integrand in the integral for the scattering amplitude in th... We demonstrate a new technique for calculating proton-proton inelastic cross-section, which allows one by application of the Laplace' method replace the integrand in the integral for the scattering amplitude in the vicinity of the maximum point by expression of Gaussian type. This, in turn, allows us to overcome the computational difficulties for the calculation of the integrals expressing the cross section to sufficiently large numbers of particles. We have managed to overcome these problems in calculating the proton-proton inelastic cross-section for production (n ≤ 8) number of secondary particles in within the framework of φ3 model. As the result the obtained dependence of inelastic cross-section and total scattering cross-section on the energy √s are qualitative agrees with the experimental data. Such description of total cross-section behavior differs considerably from existing now description, where reggeons exchange with the intercept greater than unity is considered. 展开更多
关键词 INELASTIC SCATTERING cross-SECTION Total SCATTERING cross-SECTION Laplace Method Virtuality Multi-Peripheral model Regge Theory
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