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5D World-Universe Model Space-Time-Energy 被引量:3
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2015年第1期25-34,共10页
5D Space-Time-Energy World-Universe Model is a unified model of the World built around the concept of Medium, composed of massive particles (protons, electrons, photons, neutrinos, and dark matter particles). The Mode... 5D Space-Time-Energy World-Universe Model is a unified model of the World built around the concept of Medium, composed of massive particles (protons, electrons, photons, neutrinos, and dark matter particles). The Model provides a mathematical framework that enables precise calculation of medium-bound physical parameters: Hubble’s parameter, intergalactic plasma parameters, temperature of microwave background radiation and the rest mass of photons. This paper aligns the World-Universe Model (WUM) with the theoretical framework developed by Prof. P. S. Wesson, albeit assigning a new physical meaning to the fifth coordinate. In the World-Universe Model, the fifth dimension is associated with the total energy of the Medium of the World, and the gravitomagnetic parameter of the Medium serves as the dimension-transposing parameter. 展开更多
关键词 5D World-Universe model space-Time-Energy Medium of the World Intergalactic Plasma Microwave BACKGROUND Radiation Mass VARYING PHOTONS
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Orbit Weighting Scheme in the Context of Vector Space Information Retrieval
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作者 Ahmad Ababneh Yousef Sanjalawe +2 位作者 Salam Fraihat Salam Al-E’mari Hamzah Alqudah 《Computers, Materials & Continua》 SCIE EI 2024年第7期1347-1379,共33页
This study introduces the Orbit Weighting Scheme(OWS),a novel approach aimed at enhancing the precision and efficiency of Vector Space information retrieval(IR)models,which have traditionally relied on weighting schem... This study introduces the Orbit Weighting Scheme(OWS),a novel approach aimed at enhancing the precision and efficiency of Vector Space information retrieval(IR)models,which have traditionally relied on weighting schemes like tf-idf and BM25.These conventional methods often struggle with accurately capturing document relevance,leading to inefficiencies in both retrieval performance and index size management.OWS proposes a dynamic weighting mechanism that evaluates the significance of terms based on their orbital position within the vector space,emphasizing term relationships and distribution patterns overlooked by existing models.Our research focuses on evaluating OWS’s impact on model accuracy using Information Retrieval metrics like Recall,Precision,InterpolatedAverage Precision(IAP),andMeanAverage Precision(MAP).Additionally,we assessOWS’s effectiveness in reducing the inverted index size,crucial for model efficiency.We compare OWS-based retrieval models against others using different schemes,including tf-idf variations and BM25Delta.Results reveal OWS’s superiority,achieving a 54%Recall and 81%MAP,and a notable 38%reduction in the inverted index size.This highlights OWS’s potential in optimizing retrieval processes and underscores the need for further research in this underrepresented area to fully leverage OWS’s capabilities in information retrieval methodologies. 展开更多
关键词 Information retrieval orbit weighting scheme semantic text analysis Tf-Idf weighting scheme vector space model
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Motion and Special Relativity in Complex Spaces
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作者 Jerzy K. Filus 《Journal of Applied Mathematics and Physics》 2024年第1期330-361,共32页
A natural extension of the Lorentz transformation to its complex version was constructed together with a parallel extension of the Minkowski M<sup>4</sup> model for special relativity (SR) to complex C<... A natural extension of the Lorentz transformation to its complex version was constructed together with a parallel extension of the Minkowski M<sup>4</sup> model for special relativity (SR) to complex C<sup>4</sup> space-time. As the [signed] absolute values of complex coordinates of the underlying motion’s characterization in C<sup>4</sup> one obtains a Newtonian-like type of motion whereas as the real parts of the complex motion’s description and of the complex Lorentz transformation, all the SR theory as modeled by M<sup>4</sup> real space-time can be recovered. This means all the SR theory is preserved in the real subspace M<sup>4</sup> of the space-time C<sup>4</sup> while becoming simpler and clearer in the new complex model’s framework. Since velocities in the complex model can be determined geometrically, with no primary use of time, time turns out to be definable within the equivalent theory of the reduced complex C<sup>4</sup> model to the C<sup>3</sup> “para-space” model. That procedure allows us to separate time from the (para)space and consider all the SR theory as a theory of C<sup>3</sup> alone. On the other hand, the complex time defined within the C<sup>3</sup> theory is interpreted and modeled by the single separate C<sup>1</sup> complex plane. The possibility for application of the C<sup>3</sup> model to quantum mechanics is suggested. As such, the model C<sup>3</sup> seems to have unifying abilities for application to different physical theories. 展开更多
关键词 Special Relativity Complex space and Time models and Dramatic SR Simplification Complex Time and space Separation Complex Time Interpretation
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基于CiteSpace知识图谱的近20年城市开放空间研究
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作者 耿萌萌 《住宅产业》 2024年第2期28-31,35,共5页
在城市土地存量化利用背景下,如何盘活碎片化城市开放空间、营造高质量城市开放空间体系成为人居环境学科面临的困境。本文利用CiteSpace软件对城市开放空间近20年的文献进行图示化分析,整合不同视角的开放空间研究,总结开放空间研究现... 在城市土地存量化利用背景下,如何盘活碎片化城市开放空间、营造高质量城市开放空间体系成为人居环境学科面临的困境。本文利用CiteSpace软件对城市开放空间近20年的文献进行图示化分析,整合不同视角的开放空间研究,总结开放空间研究现状与研究前沿。同时,从量化分析模型角度归纳总结基于不同角度开放空间量化评价方法。通过对开放空间理论研究与量化方法研究总结,探索开放空间研究的总体趋势与发展方向,为城市更新新阶段开放空间规划设计提供研究思路。 展开更多
关键词 开放空间 空间 量化模型
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Physical Space Was Not Expanding
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作者 Youqi Wang 《Journal of Modern Physics》 2024年第5期634-673,共40页
Plurality of characteristic peaks observed in number density distribution of galaxy redshift reveals that extent of physical space has been finite. Significant portion of observed celestial objects is found pair-wise ... Plurality of characteristic peaks observed in number density distribution of galaxy redshift reveals that extent of physical space has been finite. Significant portion of observed celestial objects is found pair-wise associated, i.e., the observed lights were emitted from one and same luminescent source but seen at different sky directions of observer, which is a unique phenomenon that can occur but only in finite space. Cosmic microwave radiation has always been interpreted as afterglow of Big Bang event. However, such radiation is shown unobservable to current observer if Hubble-Lemaître Correlation is interpreted as caused by receding motion of celestial objects. On the other hand, cosmic radiation can be understood as a common and ordinary phenomenon due to space lens, a unique property only of finite space. From Sloan Digital Sky Survey data, internal diameter of physical space is measured as 2.0 billion light years. If celestial objects were receding, hence physical space was expanding, then characteristic peaks of finite physical space should not appear evenly in number density distribution of redshift of the objects but more sparsely with respect to redshift increase. However, as revealed by the data, locations of the characteristic peaks in the distributions are rather even that do not match the locations as required by receding motion of object. Therefore, as evidenced by the data, physical space was not expanding, at least during the recent 18 billion years. In addition, considerable portion of observed quasars is found sharing a common factor of ~1/2 for their respective gravitation redshifts. 展开更多
关键词 Geometry of Physical space Big Bang model ASTROPHYSICS
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Establishing formal state space models via quantization forquantum control systems 被引量:2
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作者 DongDaoyi ChenZonghai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期398-402,共5页
Formal state space models of quantum control systems are deduced and a scheme to establish formal state space models via quantization could been obtained for quantum control systems is proposed. State evolution of qua... Formal state space models of quantum control systems are deduced and a scheme to establish formal state space models via quantization could been obtained for quantum control systems is proposed. State evolution of quantum control systems must accord with Schrdinger equations, so it is foremost to obtain Hamiltonian operators of systems. There are corresponding relations between operators of quantum systems and corresponding physical quantities of classical systems, such as momentum, energy and Hamiltonian, so Schrdinger equation models of corresponding quantum control systems via quantization could been obtained from classical control systems, and then establish formal state space models through the suitable transformation from Schrdinger equations for these quantum control systems. This method provides a new kind of path for modeling in quantum control. 展开更多
关键词 quantum control systems formal state space models quantization.
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Remaining Useful Life Prediction for Aero-Engines Combining Sate Space Model and KF Algorithm 被引量:3
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作者 Cai Jing Zhang Li Dong Ping 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第3期265-271,共7页
The key to failure prevention for aero-engine lies in performance prediction and the exhaust gas temperature margin(EGTM)is used as the most important degradation parameter to obtain the operating performance of the a... The key to failure prevention for aero-engine lies in performance prediction and the exhaust gas temperature margin(EGTM)is used as the most important degradation parameter to obtain the operating performance of the aero-engine.Because of the complex environment interference,EGTM always has strong randomness,and the state space based degradation model can identify the noisy observation from the true degradation state,which is more close to the actual situations.Therefore,a state space model based on EGTM is established to describe the degradation path and predict the remaining useful life(RUL).As one of the most effective methods for both linear state estimation and parameter estimation,Kalman filter(KF)is applied.Firstly,with EGTM degradation data,state space model approach is used to set up a state space model for aero-engine.Secondly,RUL of aero-engine is analyzed,and expected RUL and distribution of RUL are determined.Finally,the sate space model and KF algorithm are applied to an example of CFM-56aero-engine.The expected RUL is predicted,and corresponding probability density distribution(PDF)and cumulative distribution function(CDF)are given.The result indicates that the accuracy of RUL prediction reaches 7.76%ahead 580 flight cycles(FC),which is more accurate than linear regression,and therefore shows the validity and rationality of the proposed method. 展开更多
关键词 remaining useful life exhaust gas temperature margin(EGTM) Kalman filter Sate space model
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Application of the state space model to the system of wave energy conversion Analytical method for wave forces on singleoscillating rectangular buoy 被引量:1
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作者 ZHENGYonghong SUNXiaoyan +2 位作者 YOUYage SHENYongming WUBijun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第4期757-765,共9页
A new analytical method is proposed to analyze the force acting on a rectangular oscillating buoy due to linear waves.In the method a new analytical expression for the diffraction velocity potential is obtained first ... A new analytical method is proposed to analyze the force acting on a rectangular oscillating buoy due to linear waves.In the method a new analytical expression for the diffraction velocity potential is obtained first by use of theeigenfunction expansion method and then the wave excitation force is calculated by use of the known incident wavepotential and the diffraction potential. Compared with the classical analytical method, it can be seen that the presentmethod is simpler for a two-dimensional problem due to the comparable effort needed for the computation ofdiffraction potential and for that of radiated potential. To verify the correctness of the method, a classical example inthe reference is recomputed and the obtained results are in good accordance with those by use of other methods,which shows that the present method is correct. 展开更多
关键词 state space model oscillating buoy device HEAVE wave force analytical method
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Quantum-dot Semiconductor Optical Amplifiers in State Space Model 被引量:1
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作者 Hussein Taleb Kambiz Abedi Saeed Golmohammadi 《计算物理》 CSCD 北大核心 2013年第4期605-612,共8页
A state space model(SSM) is derived for quantum-dot semiconductor optical amplifiers(QD-SOAs).Rate equations of QD-SOA are formulated in the form of state update equations,where average occupation probabilities along ... A state space model(SSM) is derived for quantum-dot semiconductor optical amplifiers(QD-SOAs).Rate equations of QD-SOA are formulated in the form of state update equations,where average occupation probabilities along QD-SOA cavity are considered as state variables of the system.Simulations show that SSM calculates QD-SOA′s static and dynamic characteristics with high accuracy. 展开更多
关键词 QUANTUM-DOT rate equation model semiconductor optical amplifiers state space model
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Development of Operational Space Weather Prediction Models 被引量:1
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作者 GONG Jiancun LIU Siqing +7 位作者 SHI Liqin LUO Bingxian CHEN Yanhong HUANG Wengeng CAO Jinbin XIE Lun LEI Jiuhou TANG Weiwei 《空间科学学报》 CAS CSCD 北大核心 2014年第5期688-702,共15页
In this report, we summarize the needs of space weather models, and recommend that developing operational prediction models, rather than transitioning from research to operation, is a more feasible and critical way fo... In this report, we summarize the needs of space weather models, and recommend that developing operational prediction models, rather than transitioning from research to operation, is a more feasible and critical way for space weather services in the near future. Operational models for solar wind speed, geomagnetic indices, magnetopause, plasma sheet energetic electrons, inner boundary of ion plasma sheet, energetic electrons in outer radiation belt, and thermospheric density at low Earth orbit, have been developed and will be introduced briefly here. Their applications made a big progress in space weather services during the past two years in China. 展开更多
关键词 OPERATIONAL model space WEATHER PREDICTION
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Space station short-term mission planning using ontology modelling and time iteration 被引量:5
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作者 Huijiao Bu Jin Zhang Yazhong Luo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期407-421,共15页
This paper studies the problem of the space station short-term mission planning, which aims to allocate the executing time of missions effectively, schedule the corresponding resources reasonably and arrange the time ... This paper studies the problem of the space station short-term mission planning, which aims to allocate the executing time of missions effectively, schedule the corresponding resources reasonably and arrange the time of the astronauts properly. A domain model is developed by using the ontology theory to describe the concepts, constraints and relations of the planning domain formally, abstractly and normatively. A method based on time iteration is adopted to solve the short-term planning problem. Meanwhile, the resolving strategies are proposed to resolve different kinds of conflicts induced by the constraints of power, heat, resource, astronaut and relationship. The proposed approach is evaluated in a test case with fifteen missions, thirteen resources and three astronauts. The results show that the developed domain ontology model is reasonable, and the time iteration method using the proposed resolving strategies can successfully obtain the plan satisfying all considered constraints. 展开更多
关键词 space station mission planning ontology modelling time iteration
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Model of Reflection Spectra of Rock Surface in 2π Space 被引量:9
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作者 ZHAOHongying ZHAOHu +1 位作者 YANLei ZHAOYunsheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期843-847,共5页
This paper deals with reflection spectra and polarized reflection spectra of 20 sorts of rock in 2π space, and then creates a model of reflection spectra of rock surface in 2π space. We measured the change of reflec... This paper deals with reflection spectra and polarized reflection spectra of 20 sorts of rock in 2π space, and then creates a model of reflection spectra of rock surface in 2π space. We measured the change of reflection and polarized reflection spectra as altering the incidence angle, vertex angle, azimuth angle, band and polarization. The results show that influence of the incidence angle on spectral curves is very strong. And when the vertex angle is constant, the horizontal azimuth polarizes rock spectra, and distorts the circular spectrum to become elliptic. The polarization influences the reflection intensity of rock spectra, but has no evident influence on the characteristics of wave forms of rock in 2π space. Therefore, we can describe the whole reflection spectral characteristics, including polarization, of rock surface in 2π space by measuring and calculating the e and p values in several key directions. 展开更多
关键词 model reflection spectrum ROCK space
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Remaining Useful Life Model and Assessment of Mechanical Products: A Brief Review and a Note on the State Space Model Method 被引量:7
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作者 Yawei Hu Shujie Liu +1 位作者 Huitian Lu Hongchao Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第1期11-30,共20页
The remaining useful life(RUL) prediction of mechanical products has been widely studied for online system performance reliability, device remanufacturing, and product safety(safety awareness and safety improvement). ... The remaining useful life(RUL) prediction of mechanical products has been widely studied for online system performance reliability, device remanufacturing, and product safety(safety awareness and safety improvement). These studies incorporated many di erent models, algorithms, and techniques for modeling and assessment. In this paper, methods of RUL assessment are summarized and expounded upon using two major methods: physics model based and data driven based methods. The advantages and disadvantages of each of these methods are deliberated and compared as well. Due to the intricacy of failure mechanism in system, and di culty in physics degradation observation, RUL assessment based on observations of performance variables turns into a science in evaluating the degradation. A modeling method from control systems, the state space model(SSM), as a first order hidden Markov, is presented. In the context of non-linear and non-Gaussian systems, the SSM methodology is capable of performing remaining life assessment by using Bayesian estimation(sequential Monte Carlo). Being e ective for non-linear and non-Gaussian dynamics, the methodology can perform the assessment recursively online for applications in CBM(condition based maintenance), PHM(prognostics and health management), remanufacturing, and system performance reliability. Finally, the discussion raises concerns regarding online sensing data for SSM modeling and assessment of RUL. 展开更多
关键词 REMAINING useful life State space model Online ASSESSMENT BAYESIAN estimation Particle filter REMANUFACTURING
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Traffic condition estimation with pre-selection space time model 被引量:4
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作者 董宏辉 孙晓亮 +2 位作者 贾利民 李海舰 秦勇 《Journal of Central South University》 SCIE EI CAS 2012年第1期206-212,共7页
A pre-selection space time model was proposed to estimate the traffic condition at poor-data-detector,especially non-detector locations.The space time model is better to integrate the spatial and temporal information ... A pre-selection space time model was proposed to estimate the traffic condition at poor-data-detector,especially non-detector locations.The space time model is better to integrate the spatial and temporal information comprehensibly.Firstly,the influencing factors of the "cause nodes" were studied,and then the pre-selection "cause nodes" procedure which utilizes the Pearson correlation coefficient to evaluate the relevancy of the traffic data was introduced.Finally,only the most relevant data were collected to compose the space time model.The experimental results with the actual data demonstrate that the model performs better than other three models. 展开更多
关键词 时空模型 模型估计 交通状况 预选 Pearson相关系数 交通条件 数据检测 影响因素
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The rough representation and measurement of quotient structure in algebraic quotient space model 被引量:5
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作者 陈林书 Wang Jiayang 《High Technology Letters》 EI CAS 2017年第3期293-297,共5页
Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an... Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an equivalence relation. In this paper,definitions were given and formulas of the lower quotient congruence and upper quotient congruence were calculated to roughly represent the quotient structure. Then the accuracy and roughness were defined to measure the quotient structure in quantification. Finally,a numerical example was given to demonstrate that the rough representation and measuring methods are efficient and applicable. The work has greatly enriched the algebraic quotient space model and granular computing theory. 展开更多
关键词 空间模型 度量方法 商结构 代数 计算理论 等价关系 数值算例 粗糙度
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基于CiteSpace文献计量分析的生态网络构建研究进展
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作者 栾春凤 郭欣然 陈敏超 《安徽农业科学》 CAS 2023年第6期237-243,247,共8页
生态网络构建作为一种有效的生态手段,对于保护物种多样性,建设城市生态空间及优化国土空间资源配置方面有积极意义。利用Arcgis平台运算、对遥感数据解译利用等新技术,应用层次分析法(AHP)、专家打分法(德尔菲法)等分析方法使生态网络... 生态网络构建作为一种有效的生态手段,对于保护物种多样性,建设城市生态空间及优化国土空间资源配置方面有积极意义。利用Arcgis平台运算、对遥感数据解译利用等新技术,应用层次分析法(AHP)、专家打分法(德尔菲法)等分析方法使生态网络的构建更加精准。以CNKI、WOS为数据源,用知识图谱计算工具CiteSpace进行定量分析,通过数据可视化与内容的结合进行研究,对于构建生态网络方面的研究进展、研究方法进行分析,特别是针对“MCR模型”在生态网络的应用进行深入研究,对不同尺度范围绿地生态网络构建方法进行总结,最后对未来研究发展态势作出展望。结果表明,我国基于MCR模型构建生态网络的研究,按照发文量可分为3个阶段,即启蒙阶段、快速发展阶段、稳步发展阶段;而现阶段最小阻力模型(MCR)在生态网络的应用已经趋于成熟,只是在因子选取及赋值方面未形成统一科学标准;此外,研究尺度呈现多元化,涉及市、省、城市群等多尺度。 展开更多
关键词 生态网络 国土空间规划 城市绿地 最小阻力模型(MCR) CITEspace
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Design Criterion for Fixture Layout Based on the State Space Model in M ultistation Assembly Processes 被引量:2
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作者 张磊 周一帆 +1 位作者 张志胜 史金飞 《Journal of Donghua University(English Edition)》 EI CAS 2013年第3期175-181,共7页
The fixture layout is crucial to assure the product quality in a multistation assembly process(MAP).A well-designed fixture layout will make the final product's variability be insensitive to the fixture variation ... The fixture layout is crucial to assure the product quality in a multistation assembly process(MAP).A well-designed fixture layout will make the final product's variability be insensitive to the fixture variation inputs.As the basis of the fixture layout design,the design criterion plays an important role in the effectiveness of a solution and the optimization efficiency.In this paper,an effective and efficient design criterion is proposed for the fixture layout with a fixed reference point(FRP)in an MAP.First of all,a state space model for the individual part's variation propagation and accumulation is developed,which is the mathematical foundation of the proposed criterion.Then,based on this model,a novel design criterion used to evaluate the performance of the fixture layout is proposed for the fixture layout with an FRP.Finally,a method extracted from the proposed design criterion is developed for quick fixture layout design.A four-station assembly process is used to validate the effectiveness and efficiency of the proposed models and methods. 展开更多
关键词 化学 化学原理 化学方法 高分子化学
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Processing Approach of Non-linear Adjustment Models in the Space of Non-linear Models
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作者 LI Chaokui ZHU Qing SONG ChengfangLI Chaokui,associate professor,Ph.D,State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,129 Luoyu Road,Wuhan 430079,China. 《Geo-Spatial Information Science》 2003年第2期25-30,共6页
This paper investigates the mathematic features of non-linear models and discusses the processing way of non-linear factors which contributes to the non-linearity of a non-linear model. On the basis of the error defin... This paper investigates the mathematic features of non-linear models and discusses the processing way of non-linear factors which contributes to the non-linearity of a non-linear model. On the basis of the error definition,this paper puts forward a new adjustment criterion, SGPE.Last,this paper investigates the solution of a non-linear regression model in the non-linear model space and makes the comparison between the estimated values in non-linear model space and those in linear model space. 展开更多
关键词 非线性调节模型 测量误差 精确度 空间非线性模型
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Modeling and of Diatom Mud in Residential Space and the Application Scenario Research 被引量:1
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作者 Wei Xiaohui 《International Journal of Technology Management》 2017年第1期10-12,共3页
关键词 硅藻 居住空间 应用 建模 环保意识 装饰涂料 消费观念 市场前景
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Analytical Charge Voltage Model in MOS InversionLayer Based on Space Charge Capacitance
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作者 马玉涛 刘理天 李志坚 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2000年第10期955-961,共7页
The concept of Space Charge Capacitance (SCC) is proposed and used to make a novel analytical charge model of quantized inversion layer in MOS structures. Based on SCC, continuous expressions of surface potential and ... The concept of Space Charge Capacitance (SCC) is proposed and used to make a novel analytical charge model of quantized inversion layer in MOS structures. Based on SCC, continuous expressions of surface potential and inversion layer carrier density are derived. Quantum mechanical effects on both inversion layer carrier density and surface potential are extensively included. The accuracy of the model is verified by the numerical solution to Schrodinger and Poisson equation and the model is demonstrated,too. 展开更多
关键词 MOS器件 模式描述 可变电压模式 基板 半导体
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