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On the Application of Mixed Models of Probability and Convex Set for Time-Variant Reliability Analysis
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作者 Fangyi Li Dachang Zhu Huimin Shi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1981-1999,共19页
In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems... In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems typically involve a complexmultilevel nested optimization problem,which can result in an enormous amount of computation.To this end,this paper studies the time-variant reliability evaluation of structures with stochastic and bounded uncertainties using a mixed probability and convex set model.In this method,the stochastic process of a limit-state function with mixed uncertain parameters is first discretized and then converted into a timeindependent reliability problem.Further,to solve the double nested optimization problem in hybrid reliability calculation,an efficient iterative scheme is designed in standard uncertainty space to determine the most probable point(MPP).The limit state function is linearized at these points,and an innovative random variable is defined to solve the equivalent static reliability analysis model.The effectiveness of the proposed method is verified by two benchmark numerical examples and a practical engineering problem. 展开更多
关键词 mixed uncertainty probability model convex model time-variant reliability analysis
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Dendroclimatological study of Sabina saltuaria and Abies faxoniana in the mixed forests of the Qionglai Mountains,eastern Tibetan Plateau 被引量:1
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作者 Teng Li Jianfeng Peng +3 位作者 Tsun Fung Au Jingru Li Jinbao Li Yue Zhang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期72-82,共11页
Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan Plateau.Climate-growth relationship analysis indicated that the two co-e... Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan Plateau.Climate-growth relationship analysis indicated that the two co-exist-ing species reponded similarly to climate factors,although S.saltuaria was more sensitive than A.faxoniana.The strong-est correlation was between S.saltuaria chronology and regional mean temperatures from June to November.Based on this relationship,a regional mean temperature from June to November for the period 1605-2016 was constructed.Reconstruction explained 37.3%of the temperature variance during th period 1961-2016.Six major warm periods and five major cold periods were identified.Spectral analysis detected significant interannual and multi-decadal cycles.Reconstruction also revealed the influence of the Atlantic Multi-decadal Oscillation,confirming its importance on climate change on the eastern Tibetan Plateau. 展开更多
关键词 Tree-ring analysis mixed forests DENDROCLIMATOLOGY Qionglai Mountains
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Reliability Analysis of a Mixed Redundant Model in C 3I System 被引量:1
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作者 徐勇 侯朝桢 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期324-330,共7页
Aim To define a mixed redundant model(MRM), improving the reliability of C 3I system. Methods The model combined the technology characters of two? unit system with one warm stand by unit and function substitute s... Aim To define a mixed redundant model(MRM), improving the reliability of C 3I system. Methods The model combined the technology characters of two? unit system with one warm stand by unit and function substitute system. The reliability and availability equations of MRM were deduced. Results and Conclusion Compared with several other reliability models, it has obvious effect upon improving the system reliability. The effect? cost rate is very high among these models. The model can be used in reliability design, evaluation and check of C 3I system. Only a little attached cost is needed to improve C 3I system reliability effectively. 展开更多
关键词 C 3I system reliability analysis mixed redundant model
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Game Analysis of Regulation for Online Prescription Drugs under Customer Feedback Mechanism
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作者 Du Peng Huang Zhe Dong Li 《Asian Journal of Social Pharmacy》 2024年第2期147-158,共12页
Objective To study the way to better regulate the online sales of prescription drugs,and to provide reference for the adjustment of relevant policies since the online sales of prescription drugs has become an inevitab... Objective To study the way to better regulate the online sales of prescription drugs,and to provide reference for the adjustment of relevant policies since the online sales of prescription drugs has become an inevitable trend.Methods A game model was constructed for the strategy choice of pharmaceutical e-commerce platform,customers and government departments based on differential game theory and Nash equilibrium game model to analyze the pure strategy Nash equilibrium,Nash equilibrium dominant strategy of each subject and the mixed strategy Nash equilibrium under different conditions.Besides,Matlab was used to carry out simulation analysis.Results and Conclusion The study shows that:(1)Improving the credibility of the government and reducing the cost of government regulation can not only make the pharmaceutical e-commerce platform operate with high quality,but also give greater play to government functions;(2)The greater the influence of social evaluation on pharmaceutical e-commerce platforms,the lower the cost of high-quality operation of pharmaceutical e-commerce platform,and the greater the probability of customer choosing real evaluation strategy;(3)The greater the customers’perception of potential risk,the greater the compensation,and the lower the cost of reporting.Then,the greater the probability that government departments will choose strict regulation.Finally,the model solution and simulation analysis are combined to provide countermeasures and suggestions for the safety regulation of online sales of prescription drugs. 展开更多
关键词 online prescription drug sale Nash equilibrium simulation analysis mixed strategy game
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Analysis of Young Girls’Eagerness to Spend for Disney Virtual Characters Based on Marketing Mix Theory
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作者 HUANG Xiaoyu 《Psychology Research》 2023年第4期188-194,共7页
A virtual character is a design of a fictitious creature with distinctive characteristics created by people,and Disney virtual characters are those Intellectual Property(IP)images that appeared in Disneyland and Disne... A virtual character is a design of a fictitious creature with distinctive characteristics created by people,and Disney virtual characters are those Intellectual Property(IP)images that appeared in Disneyland and Disney movies.This investigation aimed to explore why many younger females are keen to spend money on Disney virtual characters.This paper adopted the Marketing Mix Theory strategy(product,price,placement,and promotion(4P)),and the SWOT analysis method has been utilized.This paper investigated the relationship between the 4Ps and consumers’purchasing intentions,and it turned out that unique design and effective promotion in this Disney case would promote consumers’purchase intention,while the higher price and less accessible placements affected their purchase intentions.Thus,the high price and limited places somewhat inhibit customers’desire to buy;due to the attractiveness of the product itself and the promotion on the internet,the target consumers are still willing to consume. 展开更多
关键词 Marketing mix Theory 4P SWOT(strengths WEAKNESS opportunities threats)analysis DISNEY virtual characters
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MIXED ENERGY METHOD FOR SOLUTION OF QUADRATIC PROGRAMMING PROBLEMS AND ELASTIC-PLASTIC ANALYSIS OF TRUSS STRUCTURES 被引量:1
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作者 Zhong Wanxie Zhang Hongwu 《Acta Mechanica Solida Sinica》 SCIE EI 2002年第1期1-8,共8页
A new algorithm for the solution of quadratic programming problemsis put forward in terms of the mixed energy theory and is furtherused for the incremental solution of elastic-plastic trussstructures. The method propo... A new algorithm for the solution of quadratic programming problemsis put forward in terms of the mixed energy theory and is furtherused for the incremental solution of elastic-plastic trussstructures. The method proposed is different from the traditionalone, for which the unknown variables are selected just in one classsuch as displacements or stresses. The present method selects thevariables in the mixed form with both displacement and stress. As themethod is established in the hybrid space, the information found inthe previous incremental step can be used for the solution of thepresent step, making the algorithm highly effi- cient in thenumerical solution process of quadratic programming problems. Theresults obtained in the exm- ples of the elastic-plastic solution ofthe truss structures verify what has been predicted in thetheoretical anal- ysis. 展开更多
关键词 elastic-plastic analysis mixed energy method quadratic programming problem
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EVOLUTION FILTRATION PROBLEMS WITH SEAWATER INTRUSION: TWO-PHASE FLOW DUAL MIXED VARIATIONAL ANALYSIS 被引量:1
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作者 Gonzalo ALDUNCIN 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1142-1162,共21页
Tow-phase flow mixed variational formulations of evolution filtration problems with seawater intrusion are analyzed. A dual mixed fractional flow velocity-pressure model is considered with an air-fresh water and a fre... Tow-phase flow mixed variational formulations of evolution filtration problems with seawater intrusion are analyzed. A dual mixed fractional flow velocity-pressure model is considered with an air-fresh water and a fresh water-seawater characterization. For analysis and computational purposes, spatial decompositions based on nonoverlapping multidomains, above and below the sea level, are variationally introduced with internal boundary fluxes dualized as weak transmission constraints. Further, parallel augmented and exactly penalized duality algorithms, and proximation semi-implicit time marching schemes, are established and analyzed. 展开更多
关键词 two-phase flow in coastal aquifers fractional two-phase flow dual mixed variational analysis macro-hybrid variational formulations augmented exactly penalized duality algorithms proximation semi-implicit time marching schemes
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Mixed Music Analysis with Extended Specmurt
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作者 Daiki Nishimura Toru Nakashika +1 位作者 Tetsuya Takiguchi Yasuo Ariki 《Journal of Software Engineering and Applications》 2013年第5期274-279,共6页
This paper introduces a mixed music analysis method using extended specmurt analysis. Conventional specmurt can only analyze a multi-pitch music signal from a single instrument and cannot analyze a mixed music signal ... This paper introduces a mixed music analysis method using extended specmurt analysis. Conventional specmurt can only analyze a multi-pitch music signal from a single instrument and cannot analyze a mixed music signal that has several different types of instruments being played at the same time. To analyze a mixed music signal, extended specmurt is proposed. We regard the observed spectrum extracted from the mixed music as the summation of the observed spectra corresponding to each instrument. The mixed music has as many unknown fundamental frequency distributions as the number of instruments since the observed spectrum of a single instrument can be expressed as a convolution of the common harmonic structure and the fundamental frequency distribution. The relation among the observed spectrum, the common harmonic structure and the fundamental frequency distribution is transformed into a matrix representation in order to obtain the unknown fundamental frequency distributions. The equation is called extended specmurt, and the matrix of unknown components can be obtained by using a pseudo inverse matrix. The experimental result shows the effectiveness of the proposed method. 展开更多
关键词 mixed MUSIC analysis Specmurt analysis MATRIX REPRESENTATION
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End-to-end Delay Analysis for Mixed-criticality WirelessHART Networks 被引量:2
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作者 Xi Jin Jintao Wang Peng Zeng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2015年第3期282-289,共8页
WirelessHART, as a robust and reliable wireless protocol, has been widely-used in industrial wireless sensoractuator networks. Its real-time performance has been extensively studied, but limited to the single critical... WirelessHART, as a robust and reliable wireless protocol, has been widely-used in industrial wireless sensoractuator networks. Its real-time performance has been extensively studied, but limited to the single criticality case. Many advanced applications have mixed-criticality communications, where different data flows come with different levels of importance or criticality. Hence, in this paper, we study the real-time mixedcriticality communication using WirelessHART protocol, and propose an end-to-end delay analysis approach based on fixed priority scheduling. To the best of our knowledge, this is the first work that introduces the concept of mixed-criticality into wireless sensor-actuator networks. Evaluation results show the effectiveness and efficacy of our approach. © 2014 Chinese Association of Automation. 展开更多
关键词 Criticality (nuclear fission)
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A MIXED VARIATIONAL FORMULATION FOR LARGE DEFORMATION ANALYSIS OF PLATES
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作者 S.Dost B.Tabrrok 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第7期611-621,共11页
A mixed vuriational formulation for large deformation analysis of plates is introduced. In this formulation the equilibrium ami compatibility equations are satisfied identically by means of stress functions and displa... A mixed vuriational formulation for large deformation analysis of plates is introduced. In this formulation the equilibrium ami compatibility equations are satisfied identically by means of stress functions and displacement components, respectively, and the constitu,lye equations are satisfied in a least square sense. An example is solved and the results are compared with those available in the literature.Further, the functional is particularized for buckling analysis of plates and a simple example is solved to illustrate the theory. 展开更多
关键词 A mixed VARIATIONAL FORMULATION FOR LARGE DEFORMATION analysis OF PLATES
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Theoretical analysis of fluid mixing time in liquid-continuous impinging streams reactor 被引量:3
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作者 罗燕 周剑秋 +2 位作者 郭钊 余蓓 熊卉 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期3217-3222,共6页
The mixing time of impact zone in liquid-continuous impinging streams reactor(LISR) is theoretically calculated by empirical model and modern micromixing model of the fluid mixing process, and the variation laws of ma... The mixing time of impact zone in liquid-continuous impinging streams reactor(LISR) is theoretically calculated by empirical model and modern micromixing model of the fluid mixing process, and the variation laws of macromixing time and micromixing time are quantitatively discussed. The results show that under a continuous and stable operating condition, as the paddle speed increases, the macromixing time and micromixing time calculated by the two models both decrease, even in a linkage equilibrium state. Simultaneously, as the paddle speed increases, the results figured by the two models tend to be consistent. It indicates that two models both are more suitable for calculation of mixing time in high paddle speed. Compared with the existing experimental results of this type of reactor, the mixing time computed in the speed of 1500 r/min is closer to it. These conclusions can provide an important reference for systematically studying the strengthening mechanism of LISR under continuous mixing conditions. 展开更多
关键词 impinging stream reactor empirical model theoretical model mixing time comparative analysis
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Three-dimensional mixed convection stagnation-point fow past a vertical surface with second-order slip velocity
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作者 A.V.ROSCA N.C.ROSCA I.POP 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第4期641-652,共12页
This study is concerned with the three-dimensional(3D)stagnation-point for the mixed convection flow past a vertical surface considering the first-order and secondorder velocity slips.To the authors’knowledge,this is... This study is concerned with the three-dimensional(3D)stagnation-point for the mixed convection flow past a vertical surface considering the first-order and secondorder velocity slips.To the authors’knowledge,this is the first study presenting this very interesting analysis.Nonlinear partial differential equations for the flow problem are transformed into nonlinear ordinary differential equations(ODEs)by using appropriate similarity transformation.These ODEs with the corresponding boundary conditions are numerically solved by utilizing the bvp4c solver in MATLAB programming language.The effects of the governing parameters on the non-dimensional velocity profiles,temperature profiles,skin friction coefficients,and the local Nusselt number are presented in detail through a series of graphs and tables.Interestingly,it is reported that the reduced skin friction coefficient decreases for the assisting flow situation and increases for the opposing flow situation.The numerical computations of the present work are compared with those from other research available in specific situations,and an excellent consensus is observed.Another exciting feature for this work is the existence of dual solutions.An important remark is that the dual solutions exist for both assisting and opposing flows.A linear stability analysis is performed showing that one solution is stable and the other solution is not stable.We notice that the mixed convection and velocity slip parameters have strong effects on the flow characteristics.These effects are depicted in graphs and discussed in this paper.The obtained results show that the first-order and second-order slip parameters have a considerable effect on the flow,as well as on the heat transfer characteristics. 展开更多
关键词 three-dimensional(3D)mixed convection flow stagnation point flow first-order slip velocity second-order slip velocity numerical solution stability analysis
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Simulation analysis of significance and interaction of influencing factors on mixing uniformity of double-drum recycling mixing plant 被引量:1
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作者 Ma Dengcheng Gui Xue +1 位作者 Li Xuan Ma Chenglin 《Journal of Southeast University(English Edition)》 EI CAS 2022年第2期158-165,共8页
To examine the influence of the structural parameters and working parameters of a double-drum regeneration mixing station on its mixing uniformity,the influence of the discrete element method and response surface meth... To examine the influence of the structural parameters and working parameters of a double-drum regeneration mixing station on its mixing uniformity,the influence of the discrete element method and response surface method on the uniformity of the aggregate mixing when the interaction between two different factors was analyzed.A mathematical model of the influence of various factors and interactions on the coefficient of variation of the aggregates was established.The matching of each parameter was optimized with the goal of minimizing the coefficient of variation.The results show that when the aggregate particle size is different,the significance of each parameter affecting its mixing uniformity is also different.Moreover,increasing the speed and reducing the axial installation angle of the blade can reduce the coefficient of variation of the three aggregates.To obtain a good mixing uniformity,the mixing-arm phase angle when the drum inclination angle is large should be smaller than the phase angle when the drum inclination angle is small,and the mixing of large particles should not be arranged with a large mixing-arm phase angle.With a blade radial installation angle of 38°,a blade axial installation angle of 35°,a drum inclination angle of 6°,a drum rotation speed of 10 r/min,and a mixing-arm phase angle of 32°,the aggregate as a whole can exhibit the best mixing uniformity. 展开更多
关键词 double-drum recycling mixing station mixing uniformity response surface method discrete element method significance and interaction analysis
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Assessing mixing uniformity in microreactors via in-line spectroscopy
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作者 Shusaku Asano Shinji Kudo +3 位作者 Taisuke Maki Yosuke Muranaka Kazuhiro Mae Jun-ichiro Hayashi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期119-124,共6页
Mixing behavior is critical for enhancing the selectivity of fast chemical reactions in microreactors.A high Reynolds number(Re)improves the mixing rate and selectivity of the reactions,but some exceptions of increasi... Mixing behavior is critical for enhancing the selectivity of fast chemical reactions in microreactors.A high Reynolds number(Re)improves the mixing rate and selectivity of the reactions,but some exceptions of increasing side product yield with the higher Re have been reported.This study investigated the mixing uniformity in microreactors with in-line UV-vis spectroscopy to clarify the relationship between reaction selectivity and chaotic mixing with the higher Re.A colorization experiment of thymolphthalein in an acidic solution was conducted with an excess acid amount to the base to indicate a non-uniformly mixed region.Non-uniformity significantly increased with Re.At the same time,the degree of mixing,which was measured by a usual decolorization experiment,showed that the mixing rate increased with Re.The in-line analysis of the Villermaux-Dushman reaction during the mixing clarified that side product yield significantly increased with Re at around 300 and then decreased at around 1100.These results suggest the compensation effect between the mixing uniformity and mixing rate on the selectivity of the mixing-sensitive reactions.Faster mixing,characterized by a larger Re,can disturb mixing uniformity and,in some cases,decrease reaction selectivity. 展开更多
关键词 MICROREACTOR Villermaux-Dushman reaction In-line analysis mixING Mass transfer UNIFORMITY
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Assessment and Development of Two Phase Turbulent Mixing Models for Subchannel Analysis Relevant to BWR
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作者 Mohit P. Sharma Arun K. Nayak 《World Journal of Nuclear Science and Technology》 2014年第4期195-207,共13页
Determination of turbulent mixing rate of two phase flow between neighboring subchannels is an important aspect of sub channel analysis in reactor rod bundles. Various models have been developed for two phase turbulen... Determination of turbulent mixing rate of two phase flow between neighboring subchannels is an important aspect of sub channel analysis in reactor rod bundles. Various models have been developed for two phase turbulent mixing rate between subchannels. These models show that turbulent mixing rate is strongly dependent on flow regimes;their validity was examined against specific or limited experiments. It is vital to evaluate these models by comparing the predicted two phase turbulent mixing rate with available experimental data conducted for various subchannel geometries and operating conditions. This paper describes evaluation of different models for two phase turbulent mixing rate for both gas and liquid phase against large range of experimental data which are obtained from various subchannel geometries. The results indicate that there is large discrepancy between the predicted and experimental data for turbulent mixing rate. This paper provides important shortcoming of the previous work and need for the development of a new model. In the view of this, a two phase flow model is presented, which predicts both liquid and gas phase turbulent mixing rate between adjacent sub channels of reactor rod bundles. The model presented here is for slug churn flow regime, which is dominant as compared to the other regimes like bubbly flow and annular flow regimes, since turbulent mixing rate is the highest in slug churn flow regime. The present model has been tested against low pressure and temperature air-water and high pressure and temperature steam-water experimental data found that it shows good agreement with available experimental data. 展开更多
关键词 SUBCHANNEL analysis Two PHASE TURBULENT mixING Model TURBULENT mixING RATE
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Model of Simulation for Optimizing Marketing Mix Through Conjoint Analysis Case Study: Launching a Product on a New Market
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《Economics World》 2017年第4期311-315,共5页
This paper applies conjoint analysis approach to simulate and determine the optimal marketing mix for a Romanian company that struggles to face the market higher competition. The company intends to launch its product ... This paper applies conjoint analysis approach to simulate and determine the optimal marketing mix for a Romanian company that struggles to face the market higher competition. The company intends to launch its product into a new market and surveys the likelihood of getting international. The survey helps the company to gather information from clients regarding product characteristics, price, method of distribution, and promotion, according to customer preferences. Having these data, it is made a marketing simulation using conjoint analysis in order to get the optimal marketing mix in launching the product on a new market. The optimal marketing mix is given by the highest mix of utility for the clients, but sometimes the marketing manager would choose a little bit lower utility mix, forced by the company restrictions. 展开更多
关键词 marketing simulation marketing mix conjoint analysis launching a product on a new market
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Mixed-Effects Parametric Proportional Hazard Model with Generalized Log-Logistic Baseline Distribution
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作者 Maryrose Wausi Peter Samuel Musili Mwalili +1 位作者 Anthony Kibira Wanjoya Abdsalam Hassan Muse 《Journal of Data Analysis and Information Processing》 2023年第2期81-102,共22页
Clustered survival data are widely observed in a variety of setting. Most survival models incorporate clustering and grouping of data accounting for between-cluster variability that creates correlation in order to pre... Clustered survival data are widely observed in a variety of setting. Most survival models incorporate clustering and grouping of data accounting for between-cluster variability that creates correlation in order to prevent underestimate of the standard errors of the parameter estimators but do not include random effects. In this study, we developed a mixed-effect parametric proportional hazard (MEPPH) model with a generalized log-logistic distribution baseline. The parameters of the model were estimated by the application of the maximum likelihood estimation technique with an iterative optimization procedure (quasi-Newton Raphson). The developed MEPPH model’s performance was evaluated using Monte Carlo simulation. The Leukemia dataset with right-censored data was used to demonstrate the model’s applicability. The results revealed that all covariates, except age in PH models, were significant in all considered distributions. Age and Townsend score were significant when the GLL distribution was used in MEPPH, while sex, age and Townsend score were significant in MEPPH model when other distributions were used. Based on information criteria values, the Generalized Log-Logistic Mixed-Effects Parametric Proportional Hazard model (GLL-MEPPH) outperformed other models. 展开更多
关键词 Survival analysis Generalized Log-Logistic PARAMETRIC Proportional Hazard mixed-Effects Monte Carlo Maximum Likelihood Estimation
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Feasibility Analysis and Practice Research of Resource Utilization of Waste from Planting and Breeding Industry 被引量:6
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作者 肖勤 丁怡斐 金伟 《Meteorological and Environmental Research》 CAS 2010年第11期73-75,共3页
With the extending scale of agricultural production,the treatment and utilization of waste have become increasingly serious environmental problem.Taking city garden and Zhongnan pasture in Pujiang Town of Minhang Dist... With the extending scale of agricultural production,the treatment and utilization of waste have become increasingly serious environmental problem.Taking city garden and Zhongnan pasture in Pujiang Town of Minhang District in Shanghai for example,according to the analysis on discharge characteristic of waste and balance of resources and energy utilization,mixed anaerobic digestion was chosen to dispose waste based on government guidance and feasibility analysis of project,and the combining disposal and resource utilization of waste were realized in two enterprises,providing reference for close cases. 展开更多
关键词 mixed anaerobic digestion WASTE Resource utilization Feasibility analysis China
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Influences of lithofacies on fluid mobility in mixed sedimentary rocks:Insights from NMR analysis of the middle Permian Lucaogou Formation,Junggar Basin
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作者 Huricha Wu Yaohua Wang +3 位作者 Jingqiang Tan Xiao Ma Ruining Hu Wenhui Liu 《Energy Geoscience》 EI 2024年第4期108-124,共17页
The multi-source mixed sedimentation resulted in a unique series of mixed fine-grained sedimentary rocks evolved within the Permian Lucaogou Formation in the Jimusar Sag,located in the southeastern Junggar Basin,China... The multi-source mixed sedimentation resulted in a unique series of mixed fine-grained sedimentary rocks evolved within the Permian Lucaogou Formation in the Jimusar Sag,located in the southeastern Junggar Basin,China.The variety of lithofacies within this series resulted in pronounced heterogeneity of pore structures,complicating the analysis of fluid occurrence space and state within reservoirs.As a result,the impact of lithofacies on fluid mobility remains ambiguous.In this study,we employed qualitative methods,such as field emission scanning electron microscopy(FE-SEM)and thin section observation,and quantitative analyses,including X-ray diffraction(XRD),total organic carbon(TOC),vitrinite reflectance(Ro),high-pressure mercury intrusion(HPMI)porosimetry,and nuclear magnetic resonance(NMR),along with linear and grey correlation analyses.This approach helped delineate the effective pore characteristics and principal factors influencing movable fluids in the fine-grained mixed rocks of the Lucaogou Formation in the Jimusar Sag,Junggar Basin.The findings indicate the development of three fundamental lithologies within the Lucaogou Formation:fine sandstone,siltstone,and mudstone.Siltstones exhibit the highest movable fluid saturation(MFS),followed by fine sandstones and mudstones sequentially.Fluid mobility is predominantly governed by the content of brittle minerals,the sorting coefficient(Sc),effective pore connectivity(EPC),and the fractal dimension(D_(2)).High content of brittle minerals favors the preservation of intergranular pores and the generation of microcracks,thus offering more occurrence space for movable fluids.A moderate Sc indicates the presence of larger connecting throats between pores,enhancing fluid mobility.Elevated EPC suggests more interconnected pore throat spaces,facilitating fluid movement.A higher D_(2)implies a more intricate effective pore structure,increasing the surface area of the rough pores and thereby impeding fluid mobility.Ultimately,this study developed a conceptual model that illustrates fluid distribution patterns across different reservoirs in the Lucaogou Formation,incorporating sedimentary contexts.This model also serves as a theoretical framework for assessing fluid mobility and devising engineering strategies for hydrocarbon exploitation in mixed fine-grained sedimentary rocks. 展开更多
关键词 Multi-source mixed sedimentation Movable fluid Permian lucaogou formation Nuclear magnetic resonance Grey correlation analysis
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Mixed KPCA结合纹理特征的SVM盐碱土信息提取 被引量:2
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作者 崔林林 罗毅 +1 位作者 包安明 李春轩 《计算机工程与应用》 CSCD 2012年第27期211-216,共6页
核函数是核主成分分析(Kernel Principal Component Analysis,KPCA)的核心,目前使用的核函数都是单一核函数。尝试通过将光谱角径向基核函数(Spectral Angle Radial Basis Function,SA-RBF)与RBF组合形成混合核函数。在研究中,利用基于... 核函数是核主成分分析(Kernel Principal Component Analysis,KPCA)的核心,目前使用的核函数都是单一核函数。尝试通过将光谱角径向基核函数(Spectral Angle Radial Basis Function,SA-RBF)与RBF组合形成混合核函数。在研究中,利用基于该混合核函数的KPCA进行特征提取,将其光谱特征波段和纹理特征相结合用于盐碱土的SVM分类,将分类结果与其他SVM分类进行比较,结果表明:该方法优于其他SVM方法,能有效提取玛纳斯河流域绿洲区的盐碱土专题信息,分类精度是89.000%,kappa系数是0.876。 展开更多
关键词 混合核主成分分析 纹理特征分析 支持向量机 盐碱土
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