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The Usage of Two Dielectric Function Models
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作者 陈红 沈文忠 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第4期583-590,共8页
This paper presents an overview of the history, modifications, characteristics, and applications of two well known dielectric function models ——the Forouhi-Bloomer model and the Tauc-Lorentz model——which have been... This paper presents an overview of the history, modifications, characteristics, and applications of two well known dielectric function models ——the Forouhi-Bloomer model and the Tauc-Lorentz model——which have been widely used for the extraction and parameterization of optical constants in semiconductors and dielectrics. Based on analysis of their inherent characteristics and comparison via demonstrative examples, deeper and wider usage of the two models is predicted. 展开更多
关键词 dielectric function models optical constants SEMICONDUCTORS
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Molecular properties and potential energy function model of BH under external electric field 被引量:7
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作者 伍冬兰 谭彬 +2 位作者 万慧军 张新琴 谢安东 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期194-198,共5页
Using the density functional B3P86/cc-PV5Z method, the geometric structure of BH molecule under different external electric fields is optimized, and the bond lengths, dipole moments, vibration frequencies, and other p... Using the density functional B3P86/cc-PV5Z method, the geometric structure of BH molecule under different external electric fields is optimized, and the bond lengths, dipole moments, vibration frequencies, and other physical properties parameters are obtained. On the basis of setting appropriate parameters, scanning single point energies are obtained by the same method and the potential energy curves under different external fields are also obtained. These results show that the physical property parameters and potential energy curves may change with external electric field, especially in the case of reverse direction electric field. The potential energy function without external electric field is fitted by Morse potential, and the fitting parameters are obtained which are in good agreement with experimental values. In order to obtain the critical dissociation electric parameter, the dipole approximation is adopted to construct a potential model fitting the corresponding potential energy curve of the external electric field. It is found that the fitted critical dissociation electric parameter is consistent with numerical calculation, so that the constructed model is reliable and accurate. These results will provide important theoretical and experimental reference for further studying the molecular spectrum, dynamics, and molecular cooling with Stark effect. 展开更多
关键词 BH molecule potential function model external electric field
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A power function model for simulating creep mechanical properties of salt rock 被引量:2
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作者 LI Huan Ngaha Tiedeu WILLIAM +2 位作者 Jaak DAEMEN ZHOU Jun MA Chang-kun 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第2期578-591,共14页
In this paper,a new micro-creep model of salt rock is proposed based on a linear parallel bonded model(LPBM)using the two-dimensional particle flow code(PFC2D).The power function weakening form is assumed to describe ... In this paper,a new micro-creep model of salt rock is proposed based on a linear parallel bonded model(LPBM)using the two-dimensional particle flow code(PFC2D).The power function weakening form is assumed to describe the variation of the parallel bonded diameter(PBD)over time.By comparing with the parallel-bonded stress corrosion(PSC)model,a smaller stress fluctuation and smoother creep strain−time curves can be obtained by this power function model at the same stress level.The validity and adaptability of the model to simulate creep deformation of salt rock are verified through comparing the laboratory creep test curves and the Burgers model fitting result.The numerical results reveal that this model can be capable of capturing the creep deformation and damage behavior from the laboratory observations. 展开更多
关键词 salt rock creep damage particle flow code power function model
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Rough function model and rough membership function 被引量:1
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作者 Wang Yun Guan Yanyong Huang Zhiqin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期522-528,共7页
Two pairs of approximation operators, which are the scale lower and upper approximations as well as the real line lower and upper approximations, are defined. Their properties and antithesis characteristics are analyz... Two pairs of approximation operators, which are the scale lower and upper approximations as well as the real line lower and upper approximations, are defined. Their properties and antithesis characteristics are analyzed. The rough function model is generalized based on rough set theory, and the scheme of rough function theory is made more distinct and complete. Therefore, the transformation of the real function analysis from real line to scale is achieved. A series of basic concepts in rough function model including rough numbers, rough intervals, and rough membership functions are defined in the new scheme of the rough function model. Operating properties of rough intervals similar to rough sets are obtained. The relationship of rough inclusion and rough equality of rough intervals is defined by two kinds of tools, known as the lower (upper) approximation operator in real numbers domain and rough membership functions. Their relative properties are analyzed and proved strictly, which provides necessary theoretical foundation and technical support for the further discussion of properties and practical application of the rough function model. 展开更多
关键词 rough set theory rough function model indiscernibility relation rough membership function roughnumber rough interval.
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Universal triple I fuzzy reasoning algorithm of function model based on quotient space 被引量:1
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作者 Lu Qiang Shen Guanting and Liu Xiaoping 《Computer Aided Drafting,Design and Manufacturing》 2012年第1期49-60,共12页
Aiming at the deficiencies of analysis capacity from different levels and fuzzy treating method in product function modeling of conceptual design, the theory of quotient space and universal triple I fuzzy reasoning me... Aiming at the deficiencies of analysis capacity from different levels and fuzzy treating method in product function modeling of conceptual design, the theory of quotient space and universal triple I fuzzy reasoning method are introduced, and then the function modeling algorithm based on the universal triple I fuzzy reasoning method is proposed. Firstly, the product function granular model based on the quotient space theory is built, with its function granular representation and computing rules defined at the same time. Secondly, in order to quickly achieve function granular model from function requirement, the function modeling method based on universal triple I fuzzy reasoning is put forward. Within the fuzzy reasoning of universal triple I method, the small-distance-activating method is proposed as the kernel of fuzzy reasoning; how to change function requirements to fuzzy ones, fuzzy computing methods, and strategy of fuzzy reasoning are respectively investigated as well; the function modeling algorithm based on the universal triple I fuzzy reasoning method is achieved. Lastly, the validity of the function granular model and function modeling algorithm is validated. Through our method, the reasonable function granular model can be quickly achieved from function requirements, and the fuzzy character of conceptual design can be well handled, which greatly improves conceptual design. 展开更多
关键词 conceptual design function modeling fuzzy reasoning universal triple I method
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The Polynomial Function Model in Born-Infeld Theory
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作者 DAI Bing-bing ZHANG Rui-feng 《Chinese Quarterly Journal of Mathematics》 2022年第3期221-236,共16页
Based on the Lagrangian action density under Born-Infeld type dynamics and motivated by the one-dimensional prescribed mean curvature equation,we investigate the polynomial function model in Born-Infeld theory in this... Based on the Lagrangian action density under Born-Infeld type dynamics and motivated by the one-dimensional prescribed mean curvature equation,we investigate the polynomial function model in Born-Infeld theory in this paper with the form of-([10α(φ′)^(2)]φ′)′=λf(φ(x)),whereλ>0 is a real parameter,f∈C 2(0,+∞)is a nonlinear function.We are interested in the exact number of positive solutions of the above nonlinear equation.We specifically develop for the problem combined with a careful analysis of a time-map method. 展开更多
关键词 Time-map analysis Exact number of solutions Lagrangian action density The polynomial function model Born-Infeld theory
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Physics-constrained deep-inverse point spread function model:toward non-line-of-sight imaging reconstruction
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作者 Su Wu Chan Huang +4 位作者 Jing Lin Tao Wang Shanshan Zheng Haisheng Feng Lei Yu 《Advanced Photonics Nexus》 2024年第2期90-99,共10页
Non-line-of-sight(NLOS)imaging has emerged as a prominent technique for reconstructing obscured objects from images that undergo multiple diffuse reflections.This imaging method has garnered significant attention in d... Non-line-of-sight(NLOS)imaging has emerged as a prominent technique for reconstructing obscured objects from images that undergo multiple diffuse reflections.This imaging method has garnered significant attention in diverse domains,including remote sensing,rescue operations,and intelligent driving,due to its wide-ranging potential applications.Nevertheless,accurately modeling the incident light direction,which carries energy and is captured by the detector amidst random diffuse reflection directions,poses a considerable challenge.This challenge hinders the acquisition of precise forward and inverse physical models for NLOS imaging,which are crucial for achieving high-quality reconstructions.In this study,we propose a point spread function(PSF)model for the NLOS imaging system utilizing ray tracing with random angles.Furthermore,we introduce a reconstruction method,termed the physics-constrained inverse network(PCIN),which establishes an accurate PSF model and inverse physical model by leveraging the interplay between PSF constraints and the optimization of a convolutional neural network.The PCIN approach initializes the parameters randomly,guided by the constraints of the forward PSF model,thereby obviating the need for extensive training data sets,as required by traditional deep-learning methods.Through alternating iteration and gradient descent algorithms,we iteratively optimize the diffuse reflection angles in the PSF model and the neural network parameters.The results demonstrate that PCIN achieves efficient data utilization by not necessitating a large number of actual ground data groups.Moreover,the experimental findings confirm that the proposed method effectively restores the hidden object features with high accuracy. 展开更多
关键词 non-line-of-sight imaging point spread function model deep learning
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Construction of Psychological Adjustment Function Model of Music Education Based on Emotional Tendency Analysis
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作者 Bin Zhang 《International Journal of Mental Health Promotion》 2023年第5期655-671,共17页
In the face offierce competition in the social environment,mental health problems gradually get the attention of the public,in order to achieve accurate mental health data analysis,the construction of music education ... In the face offierce competition in the social environment,mental health problems gradually get the attention of the public,in order to achieve accurate mental health data analysis,the construction of music education is based on emotional tendency analysis of psychological adjustment function model.Design emotional tendency analysis of music education psychological adjustment function architecture,music teaching goal as psychological adjust-ment function architecture building orientation,music teaching content as a foundation for psychological adjust-ment function architecture and music teaching process as a psychological adjustment function architecture building,music teaching evaluation as the key of building key regulating function architecture,Establish a core literacy oriented evaluation system.Different evaluation methods were used to obtain the evaluation results.Four levels of psychological adjustment function model of music education are designed,and the psychological adjust-ment function of music education is put forward,thus completing the construction of psychological adjustment function model of music education.The experimental results show that the absolute value of the data acquisition error of the designed model is minimum,which is not more than 0.2.It is less affected by a bad coefficient and has good performance.It can quickly converge to the best state in the actual prediction process and has a strong con-vergence ability. 展开更多
关键词 Emotional tendency analysis music education psychological adjustment functional model core literacy orientation
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Transfer function modeling and analysis of the open-loop Buck converter using the fractional calculus 被引量:11
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作者 王发强 马西奎 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期232-239,共8页
Based on the fact that the real inductor and the real capacitor are fractional order in nature and the fractional calculus,the transfer function modeling and analysis of the open-loop Buck converter in a continuous co... Based on the fact that the real inductor and the real capacitor are fractional order in nature and the fractional calculus,the transfer function modeling and analysis of the open-loop Buck converter in a continuous conduction mode(CCM) operation are carried out in this paper.The fractional order small signal model and the corresponding equivalent circuit of the open-loop Buck converter in a CCM operation are presented.The transfer functions from the input voltage to the output voltage,from the input voltage to the inductor current,from the duty cycle to the output voltage,from the duty cycle to the inductor current,and the output impedance of the open-loop Buck converter in CCM operation are derived,and their bode diagrams and step responses are calculated,respectively.It is found that all the derived fractional order transfer functions of the system are influenced by the fractional orders of the inductor and the capacitor.Finally,the realization of the fractional order inductor and the fractional order capacitor is designed,and the corresponding PSIM circuit simulation results of the open-loop Buck converter in CCM operation are given to confirm the correctness of the derivations and the theoretical analysis. 展开更多
关键词 Buck converter small signal equivalent circuit model fractional calculus transfer function
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Artificial hearing systems based on functional cochlea models
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作者 Jinke Chang Sita Tarini Clark +3 位作者 Iwan Roberts Filip Hrncirik Zhipeng Zhang Manohar Bance 《International Journal of Extreme Manufacturing》 2025年第1期73-94,共22页
The cochlea is one of the most complex organs in the human body,exhibiting a complex interplay of characteristics in acoustic,mechanical,electrical,and biological functions.Functional cochlea models are an essential p... The cochlea is one of the most complex organs in the human body,exhibiting a complex interplay of characteristics in acoustic,mechanical,electrical,and biological functions.Functional cochlea models are an essential platform for studying hearing mechanics and are crucial for developing next-generation auditory prostheses and artificial hearing systems for sensorineural hearing restoration.Recent advances in additive manufacturing,organ-on-a-chip models,drug delivery platforms,and artificial intelligence have provided valuable insights into how to manufacture artificial cochlea models that more accurately replicate the complex anatomy and physiology of the inner ear.This paper reviews recent advancements in the applications of advanced manufacturing techniques in reproducing the physical,biological,and intelligent functions of the cochlea.It also outlines the current challenges to developing mechanically,electrically,and anatomically accurate functional models of the inner ear.Finally,this review identifies the major requirements and outlook for impactful research in this field going forward.Through interdisciplinary collaboration and innovation,these functional cochlea models are poised to drive significant advancements in hearing treatments,and ultimately enhance the quality of life for individuals with hearing loss. 展开更多
关键词 functional cochlea model auditory system hearing loss advanced manufacturing artificial hearing
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Functional evidential reasoning model(FERM)-A new systematic approach for exploring hazardous chemical operational accidents under uncertainty
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作者 Qianlin Wang Jiaqi Han +6 位作者 Lei Cheng Feng Wang Yiming Chen Zhan Dou Bing Zhang Feng Chen Guoan Yang 《Chinese Journal of Chemical Engineering》 2025年第5期255-269,共15页
This paper proposed a new systematic approach-functional evidential reasoning model(FERM) for exploring hazardous chemical operational accidents under uncertainty. First, FERM was introduced to identify various causal... This paper proposed a new systematic approach-functional evidential reasoning model(FERM) for exploring hazardous chemical operational accidents under uncertainty. First, FERM was introduced to identify various causal factors and their performance changes in hazardous chemical operational accidents, along with determining the functional failure link relationships. Subsequently, FERM was employed to elucidate both qualitative and quantitative operational accident information within a unified framework, which could be regarded as the input of information fusion to obtain the fuzzy belief distribution of each cause factor. Finally, the derived risk values of the causal factors were ranked while constructing multi-level accident causation chains to unveil the weak links in system functionality and the primary roots of operational accidents. Using the specific case of the “1·15” major explosion and fire accident at Liaoning Panjin Haoye Chemical Co., Ltd., seven causal factors and their corresponding performance changes were identified. Additionally, five accident causation chains were uncovered based on the fuzzy joint distribution of the functional assessment level(FAL) and reliability distribution(RD),revealing an overall increase in risk along the accident evolution path. The research findings demonstrated that FERM enabled the effective characterization, rational quantification and accurate analysis of the inherent uncertainties in hazardous chemical operational accident risks from a systemic perspective. 展开更多
关键词 functional evidential reasoning model (FERM) Accident causation analysis Operational accidents Hazardous chemical UNCERTAINTY
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Generalized functional model of maximum and minimum detectable deformation gradient for PALSAR interferometry 被引量:2
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作者 王琪洁 李志伟 +4 位作者 杜亚男 谢荣安 张杏清 蒋弥 朱建军 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期824-832,共9页
Empirical functional models for the maximum and minimum detectable deformation gradient of PALSAR interferometry were established based on coherence and discrete look numbers. Then, a least square regression method wa... Empirical functional models for the maximum and minimum detectable deformation gradient of PALSAR interferometry were established based on coherence and discrete look numbers. Then, a least square regression method was used to fit the model coefficients and thus obtain the generalized functional models for both coherence and look numbers. The experimental results with ALOS PALSAR data of Wenchuan earthquake of China show that the new model works well for judging whether the deformation gradient can be detected by the D-InSAR technology or not. The results can help researchers to choose PALSAR data and to configure processing parameters, and also benefit the interpretation of the measured surface deformation. 展开更多
关键词 PALSAR D-INSAR deformation gradient COHERENCE multilook number functional model
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A head-related transfer function model for fast synthesizing multiple virtual sound sources 被引量:1
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作者 LIANG Zhiqiang XIE Bosun 《Chinese Journal of Acoustics》 2013年第2期175-188,共14页
A head-related transfer function (HRTF) model for fast and real-time synthesizing multiple virtual sound sources is proposed. A head-related impulse response (HRIR, time- domain version of HRTF) is first decompose... A head-related transfer function (HRTF) model for fast and real-time synthesizing multiple virtual sound sources is proposed. A head-related impulse response (HRIR, time- domain version of HRTF) is first decomposed by a two-level wavelet packet and then represented by a model composed of subband filters and reconstruction filters. The coefficients of the subband filters are the zero interpolation of the wavelet coefficients of the HRIR. The coefficients of the reconstruction filters can be calculated from the wavelet function. The model is simplified by applying a threshold method to reduce the wavelet coefficients. The calculated results indicate that for a model with 30 wavelet coefficients, the error of reconstructed HRIR is about 1%. And the result of a psychoacoustic test shows that a model with 35 wavelet coefficients is perceptually indistinguishable from the original HRIR. When multiple virtual sound sources are synthesized simultaneously, the computational cost of the proposed model is much less than the traditional HRTF filters. 展开更多
关键词 HRIR HRTF A head-related transfer function model for fast synthesizing multiple virtual sound sources HEAD
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Establishment of European Regional Ionosphere Model Based on Spherical Harmonic Functions 被引量:1
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作者 Mingze Zhang 《Journal of World Architecture》 2021年第6期5-9,共5页
In order to study the temporal and spatial variation characteristics of the regional ionosphere and the modeling accuracy,the experiment is based on the spherical harmonic function model,using the GPS,Glonass,and Gali... In order to study the temporal and spatial variation characteristics of the regional ionosphere and the modeling accuracy,the experiment is based on the spherical harmonic function model,using the GPS,Glonass,and Galileo dual-frequency observation data from the 305th-334th day of the European CORS network in 2019 to establish a global ionospheric model.By analyzing and evaluating the accuracy of the global ionospheric puncture points,VTEC,and comparing code products,the test results showed that the GPS system has the most dense puncture electricity distribution,the Glonass system is the second,and the Galileo system is the weakest.The values of ionospheric VTEC calculated by GPS,Glonass and Galileo are slightly different,but in terms of trends,they are the same as those of ESA,JPL and UPC.GPS data has the highest accuracy in global ionospheric modeling.GPS,Glonass and Galileo have the same trend,but Glonass data is unstable and fluctuates greatly. 展开更多
关键词 Global ionosphere VTEC Spherical harmonic function model
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Functions of Allusions from Leppihalme’s model
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作者 倪志莉 《魅力中国》 2009年第15期188-189,共2页
The general function of allusions is often thought to add clarity and significance to ideas and descriptions.However,it would be difficult to establish an exhaustive list of mutually exclusive category
关键词 functions of Allusions from Leppihalme’s model
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Research on Function Based Method for Bio-Inspiration Knowledge Modeling and Transformation 被引量:2
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作者 谷朝臣 胡洁 彭颖红 《Journal of Shanghai Jiaotong university(Science)》 EI 2014年第2期190-198,共9页
Biological inspirations are good design mimicry resources. This paper proposes a function based approach for modeling and transformation of bio-inspiration design knowledge. A general functional modeling method for bi... Biological inspirations are good design mimicry resources. This paper proposes a function based approach for modeling and transformation of bio-inspiration design knowledge. A general functional modeling method for biological domain and engineering domain design knowledge is introduced. Functional similarity based bio-inspiration transformation between biological domain and engineering domain is proposed. The biological function topology transfer and analog solution recomposition are also discussed in this paper. 展开更多
关键词 bio-inspired design functional modeling ONTOLOGY functional reasoning knowledge transfer
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Generic functional modelling of multi-pulse auto-transformer rectifier units for more-electric aircraft applications 被引量:1
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作者 Tao YANG Serhiy BOZHKO +2 位作者 Patrick WHEELER Shaoping WANG Shuai WU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第5期883-891,共9页
The Auto-Transformer Rectifier Unit(ATRU) is one preferred solution for high-power AC/DC power conversion in aircraft. This is mainly due to its simple structure, high reliability and reduced k VA ratings. Indeed, t... The Auto-Transformer Rectifier Unit(ATRU) is one preferred solution for high-power AC/DC power conversion in aircraft. This is mainly due to its simple structure, high reliability and reduced k VA ratings. Indeed, the ATRU has become a preferred AC/DC solution to supply power to the electric environment control system on-board future aircraft. In this paper, a general modelling method for ATRUs is introduced. The developed model is based on the fact that the DC voltage and current are strongly related to the voltage and current vectors at the AC terminals of ATRUs. In this paper, we carry on our research in modelling symmetric 18-pulse ATRUs and develop a generic modelling technique. The developed generic model can study not only symmetric but also asymmetric ATRUs. An 18-pulse asymmetric ATRU is used to demonstrate the accuracy and efficiency of the developed model by comparing with corresponding detailed switching SABER models provided by our industrial partner. The functional models also allow accelerated and accurate simulations and thus enable whole-scale more-electric aircraft electrical power system studies in the future. 展开更多
关键词 Asymmetric transformer functional modelling More-Electric Aircraft Multi-pulse rectifier Transformer rectifier unit
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Time function of surface subsidence based on Harris model in mined-out area 被引量:7
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作者 Liu Xinrong Wang Junbao +2 位作者 Guo Jianqiang Yuan Hong Li Peng 《International Journal of Mining Science and Technology》 SCIE EI 2013年第2期251-254,共4页
The surface subsidence is a common environmental hazard in mined-out area. Based on careful analysis of the regularity of surface subsidence in mined-out area, we proposed a new time function based on Harris curve mod... The surface subsidence is a common environmental hazard in mined-out area. Based on careful analysis of the regularity of surface subsidence in mined-out area, we proposed a new time function based on Harris curve model in consideration of the shortage of current surface subsidence time functions. By analyzing the characteristics of the new time function, we found that it could meet the dynamic process, the velocity change process and the acceleration change process during surface subsidence. Then its rationality had been verified through project cases. The results show that the proposed time function model can give a good reflection of the regularity of surface subsidence in mined-out area and can accurately predict surface subsidence. And the prediction data of the model are a little greater than measured data on condition of proper measured data quantity, which is safety in the engineering. This model provides a new method for the analysis of surface subsidence in mined-out area and reference for future prediction, and it is valuable to engineering application. 展开更多
关键词 Mined-out area Surface subsidence Time function Harris model Prediction
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Hybrid graded element model for transient heat conduction in functionally graded materials 被引量:4
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作者 Lei-Lei Cao Qing-Hua Qin Ning Zhao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第1期128-139,共12页
This paper presents a hybrid graded element model for the transient heat conduction problem in functionally graded materials (FGMs). First, a Laplace transform approach is used to handle the time variable. Then, a f... This paper presents a hybrid graded element model for the transient heat conduction problem in functionally graded materials (FGMs). First, a Laplace transform approach is used to handle the time variable. Then, a fundamental solution in Laplace space for FGMs is constructed. Next, a hybrid graded element is formulated based on the obtained fundamental solution and a frame field. As a result, the graded properties of FGMs are naturally reflected by using the fundamental solution to interpolate the intra-element field. Further, Stefest's algorithm is employed to convert the results in Laplace space back into the time-space domain. Finally, the performance of the proposed method is assessed by several benchmark examples. The results demonstrate well the efficiency and accuracy of the proposed method. 展开更多
关键词 Graded element model functionally graded materials Hybrid FEM Transient heat conduction
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Model Selection in Estimation of Covariance Functions for Growth of Angora Goats 被引量:2
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作者 LIU Wen-zhong ZHANG Yuan ZHOU Zhong-xiao 《Agricultural Sciences in China》 CAS CSCD 2010年第7期1041-1049,共9页
Covariance functions have been proposed as an alternative to model longitudinal data in animal breeding because of their various merits in comparison to the classical analytical methods.In practical estimation,differe... Covariance functions have been proposed as an alternative to model longitudinal data in animal breeding because of their various merits in comparison to the classical analytical methods.In practical estimation,different models and polynomial orders fitted can influence the estimates of covariance functions and thus genetic parameters.The objective of this study was to select model for estimation of covariance functions for body weights of Angora goats at 7 time points.Covariance functions were estimated by fitting 6 random regression models with birth year,birth month,sex,age of dam,birth type,and relative birth date as fixed effects.Random effects involved were direct and maternal additive genetic,and animal and maternal permanent environmental effects with different orders of fit.Selection of model and orders of fit were carried out by likelihood ratio test and 4 types of information criteria.The results showed that model with 6 orders of polynomial fit for direct additive genetic and animal permanent environmental effects and 4 and 5 orders for maternal genetic and permanent environmental effects,respectively,were preferable for estimation of covariance functions.Models with and without maternal effects influenced the estimates of covariance functions greatly.Maternal permanent environmental effect does not explain the variation of all permanent environments,well suggesting different sources of permanent environmental effects also has large influence on covariance function estimates. 展开更多
关键词 Angora goats GROWTH covariance function model selection random regression model
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