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采用修正弦线模量法预测基础的非线性沉降 被引量:2
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作者 李仁平 罗勉 《三峡大学学报(自然科学版)》 CAS 2011年第1期41-45,共5页
提出在无粘性土地基中依据载荷试验测试数据反求不同应力水平条件下地基土的修正弦线模量,然后采用该参数预测地基非线性沉降的计算方法,并采用Briaud和Gibbens所做的一系列砂土地基中的基础加载试验成果进行验证.验证时首先根据1 m... 提出在无粘性土地基中依据载荷试验测试数据反求不同应力水平条件下地基土的修正弦线模量,然后采用该参数预测地基非线性沉降的计算方法,并采用Briaud和Gibbens所做的一系列砂土地基中的基础加载试验成果进行验证.验证时首先根据1 m×1 m小基础的荷载沉降观测资料反求地基土的修正弦线模量,然后采用分层总和法计算1.5 m×1.5 m、2.5 m×2.5 m及3 m×3 m基础从开始加载至极限状态的非线性全过程沉降曲线.验证结果表明:所有基础的荷载沉降计算曲线都与试验曲线相吻合,各基础持荷30 min产生25 mm与150 mm沉降量对应的荷载预测值与测量值的相对误差在10%以内,与参加这次预测研讨会的31名专家学者提交的结果相比较,本文方法获得的结果更为准确.同时说明修正弦线模量法能够很好地考虑基础沉降的尺寸效应,可以满足以沉降变形控制为目的的基础工程设计要求. 展开更多
关键词 正弦线模量 分层总和法 非线性沉降 基础加载试验
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Cointegration analysis with structural changes between consumption and economic growth in China 被引量:3
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作者 郭建平 何建敏 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期238-241,共4页
In order to investigate the existence of a stable long-run equilibrium relationship between economic growth and consumption in China, the relationship between the gross domestic product (GDP) and consumption in Chin... In order to investigate the existence of a stable long-run equilibrium relationship between economic growth and consumption in China, the relationship between the gross domestic product (GDP) and consumption in China was investigated by the cointegration analysis method. Using the Engle-Granger (EG) test and considering the possibility of structural changes, the impact of external economic shocks on the long-run equilibrium relationship between economic growth and consumption in China was analyzed. Analysis results show that without considering structural changes, the EG test cannot detect cointegration in the series subjected to structural changes; in considering structural changes, cointegration is successfully detected by specifying the dummy variable. In addition, the error correction models were constructed in different periods. This study verifies the existence of a long-run equilibrium relationship between economic growth and consumption in China, and this relationship has significantly changed in 1989 and 1997, respectively. 展开更多
关键词 cointegration with structural changes economic growth dummy variable CONSUMPTION error correction model
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GRA BASED ANALYSIS ON FACTORS INFLUENCING CO_2 EMISSIONS IN CHINA 被引量:1
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作者 董锋 李晓晖 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期152-158,共7页
How to achieve the objective of reducing CO2 emissions has been an academic focus in China recently. The factors influencing CO2 emissions are the vital issue to accomplish the arduous target. Firstly, three influenti... How to achieve the objective of reducing CO2 emissions has been an academic focus in China recently. The factors influencing CO2 emissions are the vital issue to accomplish the arduous target. Firstly, three influential factors, the energy consumption, the proportion of tertiary industry in gross domestic product (GDP), and the degree of dependence on foreign trade, are carefully selected, since all of them have closer grey relation with China's COz emissions compared with others when the grey relational analysis (GRA) method is applied. The study highlights co-integration relation of these four variables using the co-integration analysis method. And then a long-term co-integration equation and a short-term error correction model of China's CO2 emissions are devel- oped. Finally, the comparison is exerted between the forecast value and the actual value of China's CO2 emissions based on error correction model. The results and the relevant statistics tests show that the pro- posed model has better explanation capability and credibility. 展开更多
关键词 grey relational analysis(GRA) CO2 emissions co-integration test error correction model
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A Modified Groundwater Module in SWAT for Improved Streamflow Simulation in a Large, Arid Endorheic River Watershed in Northwest China 被引量:6
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作者 JIN Xin HE Chansheng +1 位作者 ZHANG Lanhui ZHANG Baoqing 《Chinese Geographical Science》 SCIE CSCD 2018年第1期47-60,共14页
Interactions between surface water and groundwater are dynamic and complex in large endorheic river watersheds in Northwest China due to the influence of both irrigation practices and the local terrain. These interact... Interactions between surface water and groundwater are dynamic and complex in large endorheic river watersheds in Northwest China due to the influence of both irrigation practices and the local terrain. These interactions interchange numerous times throughout the middle reaches, making streamflow simulation a challenge in endorheic river watersheds. In this study, we modified the linear-reservoir groundwater module in SWAT(Soil and Water Assessment Tools, a widely used hydrological model) with a new nonlinear relationship to better represent groundwater processes; we then applied the original SWAT and modified SWAT to the Heihe River Watershed, the second largest endorheic river watershed in Northwest China, to simulate streamflow. After calibrating both the original SWAT model and the modified SWAT model, we analyzed model performance during two periods: an irrigation period and a non-irrigation period. Our results show that the modified SWAT model with the nonlinear groundwater module performed significantly better during both the irrigation and non-irrigation periods. Moreover, after comparing different runoff components simulated by the two models, the results show that, after the implementation of the new nonlinear groundwater module in SWAT, proportions of runoff components changed-and the groundwater flow had significantly increased, dominating the discharge season. Therefore, SWAT coupled with the non-linear groundwater module represents the complex hydrological process in the study area more realistically. Moreover, the results for various runoff components simulated by the modified SWAT models can be used to describe the hydrological characteristics of lowland areas. This indicates that the modified SWAT model is applicable to simulate complex hydrological process of arid endorheic rivers. 展开更多
关键词 Soil and Water Assessment Tools (SWAT) GROUNDWATER irrigation streamflow Heihe River
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MobileNet network optimization based on convolutional block attention module 被引量:3
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作者 ZHAO Shuxu MEN Shiyao YUAN Lin 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第2期225-234,共10页
Deep learning technology is widely used in computer vision.Generally,a large amount of data is used to train the model weights in deep learning,so as to obtain a model with higher accuracy.However,massive data and com... Deep learning technology is widely used in computer vision.Generally,a large amount of data is used to train the model weights in deep learning,so as to obtain a model with higher accuracy.However,massive data and complex model structures require more calculating resources.Since people generally can only carry and use mobile and portable devices in application scenarios,neural networks have limitations in terms of calculating resources,size and power consumption.Therefore,the efficient lightweight model MobileNet is used as the basic network in this study for optimization.First,the accuracy of the MobileNet model is improved by adding methods such as the convolutional block attention module(CBAM)and expansion convolution.Then,the MobileNet model is compressed by using pruning and weight quantization algorithms based on weight size.Afterwards,methods such as Python crawlers and data augmentation are employed to create a garbage classification data set.Based on the above model optimization strategy,the garbage classification mobile terminal application is deployed on mobile phones and raspberry pies,realizing completing the garbage classification task more conveniently. 展开更多
关键词 MobileNet convolutional block attention module(CBAM) model pruning and quantization edge machine learning
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Rank-Defect Adjustment Model for Survey-Line Systematic Errors in Marine Survey Net 被引量:2
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作者 LIU Yanchun LI Mingsan HUANG Motao 《Geo-Spatial Information Science》 2002年第4期14-20,共7页
In this paper,the structure of systematic and random errors in marine survey net are discussed in detail and the adjustment method for observations of marine survey net is studied,in which the rank_defect characterist... In this paper,the structure of systematic and random errors in marine survey net are discussed in detail and the adjustment method for observations of marine survey net is studied,in which the rank_defect characteristic is discovered first up to now.On the basis of the survey_line systematic error model,the formulae of the rank_defect adjustment model are deduced according to modern adjustment theory.An example of calculations with really observed data is carried out to demonstrate the efficiency of this adjustment model.Moreover,it is proved that the semi_systematic error correction method used at present in marine gravimetry in China is a special case of the adjustment model presented in this paper. 展开更多
关键词 marine survey net survey_line error structure rank_defect adjustment model
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Revised Geometric Measure of Entanglement for Multipartite and Continuous Variable Systems 被引量:1
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作者 CAO Ya WANG An-Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期613-620,共8页
Based on the revised geometric measure of entanglement (RGME) proposed by us [J. Phys. A: Math. Theor. 40 (2007) 3507], we obtain the RGME of multipartite state including three-qubit GHZ state, W state, and the g... Based on the revised geometric measure of entanglement (RGME) proposed by us [J. Phys. A: Math. Theor. 40 (2007) 3507], we obtain the RGME of multipartite state including three-qubit GHZ state, W state, and the generalized Smolin state (GSS) in the presence of noise and the two-mode squeezed thermal state. Moreover, we compare their RGME with geometric measure of entanglement (GME) and relative entropy of entanglement (RE). The results indicate RGME is an appropriate measure of entanglement. Finally, we define the Gaussian GME which is an entangled monotone. 展开更多
关键词 quantum entanglement symmetric state revised geometric measure of entanglement relative entropy of entanglement
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Imperfect preventive maintenance for numerical control machine tools with log-linear virtual age process 被引量:4
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作者 郭俊锋 芮执元 +1 位作者 冯瑞成 魏兴春 《Journal of Central South University》 SCIE EI CAS 2014年第12期4497-4502,共6页
Based on the log-linear virtual age process, an imperfect preventive maintenance policy for numerical control(NC)machine tools with random maintenance quality is proposed. The proposed model is a combination of the Ki... Based on the log-linear virtual age process, an imperfect preventive maintenance policy for numerical control(NC)machine tools with random maintenance quality is proposed. The proposed model is a combination of the Kijima type virtual age model and the failure intensity adjustment model. Maintenance intervals of the proposed hybrid model are derived when the failure intensity increase factor and the restoration factor are both random variables with uniform distribution. The optimal maintenance policy in infinite time horizon is presented. A numerical example is given when the failures of NC machine tools are described by the log-linear process. Finally, a discussion is presented to show how the optimal results depend on the different cost parameters. 展开更多
关键词 reliability imperfect preventive maintenance virtual age log-linear process failure intensity
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Monetary Model of Exchange Rate Determination: Evidence From the Czech Republic, Hungary, and Poland
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作者 Victor Shevchuk 《Journal of Modern Accounting and Auditing》 2014年第1期97-103,共7页
Using a monetary model of exchange rate determination that suggests a strong link between the nominal exchange rate and a set of monetary fundamentals, exchange rate dynamics for the Czech Republic, Hungary, and Polan... Using a monetary model of exchange rate determination that suggests a strong link between the nominal exchange rate and a set of monetary fundamentals, exchange rate dynamics for the Czech Republic, Hungary, and Poland is studied. As the cointegration relationship among exchange rate, output, and the monetary fundamentals (money supply and interest rate) is found, vector autoregressions (VAR)/vector error-correction (VEC) and two-stage least squares (2SLS) error-correction models are used in this context, since both approaches allow estimating short-run correlations between exchange rates and fundamentals while taking into account the existent long-run exchange rate constraints. Based on the quarterly data for the period of 1998-2012, it is found that for all countries, an increase in the money supply, domestic output slowdown, or stronger growth abroad are factors behind a nominal exchange rate depreciation, just as predicted by the monetary model of exchange rate. However, the effects of domestic-foreign interest rate differential are quite heterogeneous, being in line with theoretical predictions of a standard monetary model for Poland only. According to the decomposition of variance, money supply and interest rates account for 30%-46% of the exchange rate variation in the Czech Republic, from 10% to 14% in Hungary, and from 23% to 42% in Poland. 展开更多
关键词 monetary model of exchange rate the Czech Republic Hungary' Poland error-correction models
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Adiabatic correction for the esterification of acetic anhydride by methanol via accurate kinetics
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作者 Ze Dong Liping Chen +2 位作者 Yingying Ma Haoliang Peng Wanghua Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第9期1954-1959,共6页
In the field of adiabatic correction for complex reactions,a simple one-stage kinetic model was used to estimate the real reaction kinetics.However,this assumption simplified the real process,inevitably generated inac... In the field of adiabatic correction for complex reactions,a simple one-stage kinetic model was used to estimate the real reaction kinetics.However,this assumption simplified the real process,inevitably generated inaccurate or even unsafe results.Therefore,it was necessary to find a new correction method for complex reactions.In this work,esterification of acetic anhydride by methanol was chosen as an object reaction of study.The reaction was studied under different conditions by Reaction Calorimeter(RC1).Then,Thermal Safety Software(TSS)was used to establish the kinetic model and estimate the parameters,where,activation energies for three stages were67.09,81.02,73.77 kJ?mol^(-1)respectively,and corresponding frequency factors in logarithmic form were 16.05,19.59,15.72 s^(-1).In addition,two adiabatic tests were performed by Vent Sizing Package2(VSP2).For accurate correction of VSP2 tests,a new correction method based on Enhanced Fisher method was proposed.Combined with kinetics,adiabatic correction of esterification reaction was achieved.Through this research,accurate kinetic parameters for a three-step kinetic model of the esterification reaction were acquired.Furthermore,the correlation coefficients between simulated curves and corrected curves were 0.976 and 0.968,which proved the accuracy of proposed new adiabatic correction method.Based on this new method,conservative corrected results were able to be acquired and be applied in safety assessment. 展开更多
关键词 Adiabatic correction KINETICS New method Complex reaction ESTERIFICATION Model reaction
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Unification of Dark Matter and Dark Energy in a Modified Entropic Force Model 被引量:1
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作者 常哲 李明华 李昕 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期184-192,共9页
In Verlinde's entropic force scenario of gravity, Newton's laws and Einstein equations can be obtained from the first principles and general assumptions. However, the equipartition law of energy is invalid at very l... In Verlinde's entropic force scenario of gravity, Newton's laws and Einstein equations can be obtained from the first principles and general assumptions. However, the equipartition law of energy is invalid at very low temperatures. We show clearly that the threshold of the equipartition law of energy is related with horizon of the universe. Thus, a one-dimensional Debye (ODD) model in the direction of radius of the modified entropic force (MEF) may be suitable in description of the accelerated expanding universe. We present a Friedmann cosmic dynamical model in the ODD-MEF framework. We examine carefully constraints on the ODD-MEF model from the Union2 compilation of the Supernova Cosmology Project (SCP) collaboration, the data from the observation of the large-scale structure (LSS) and the cosmic microwave background (CMB), i.e. SNe Ia+LSS+CMB. The combined numerical analysis gives the best-fit value of the model parameters ( -10^-9 and Ωm0= 0.224, with 2 = Xmin= 591.156. The corresponding age of the universe agrees with the result of D. Spergel et al. [J.M. Bardeen, B. Carter, and S.W. Hawking, Commun. Math. Phys. 31 (1973) 161] at 95% confidence level. The numerical result also yields an accelerated expanding universe without invoking any kind of dark energy. Taking ζ(= 2πωD/ H0 ) as a running parameter associated with the structure scale r, we obtain a possible unified scenario of the asymptotic flatness of the radial velocity dispersion of spiral galaxies, the accelerated expanding universe and the Pioneer 10/11 anomaly in the entropic force framework of Verlinde. 展开更多
关键词 dark energy dark matter
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Influence of Adoptment of Geocentric 3D Coordinate System on Chinese Existent Maps
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作者 CHENJunyong DANGYamin 《Geo-Spatial Information Science》 2005年第2期79-84,103,共7页
If a geocentric 3D coordinate system is adopted in China to replace 2D non-geocentric coordinate system, the coordinates of the surface points will be changed accordingly. The influences on the current maps of China, ... If a geocentric 3D coordinate system is adopted in China to replace 2D non-geocentric coordinate system, the coordinates of the surface points will be changed accordingly. The influences on the current maps of China, especially the topographic maps, are discussed due to the replacement of the coordinate systems. Taking the replacement of Xi’an 80 coordinate system by GRS80 for a numerical example, this paper analyzes the changes of latitude, longitude, Gauss plane coordinates of the surface points, as well as the orientation and the length changes between the points on the map, including the changes of map border lines and sheet corner points. 展开更多
关键词 replacement of coordinate system MAP geocentric 3D coordinate system
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复杂型面零件冲压回弹参考点的选择与应用
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作者 冯杨 阮峰 《锻压技术》 CAS CSCD 北大核心 2014年第3期38-41,共4页
对于复杂型面零件,冲压回弹随参考点选择不同而不同,而且精确选择很难。以最小模具修模量为目标,提出一种回弹参考点选择的方法。该方法采用计算机仿真和逆向工程技术,计算回弹值并确定最优的回弹参考点。即在仿真计算中试确定回弹参考... 对于复杂型面零件,冲压回弹随参考点选择不同而不同,而且精确选择很难。以最小模具修模量为目标,提出一种回弹参考点选择的方法。该方法采用计算机仿真和逆向工程技术,计算回弹值并确定最优的回弹参考点。即在仿真计算中试确定回弹参考点,然后将实际冲压件通过逆向工程技术重构型面,采用迭代最近点算法将重构面与设计面进行配准,计算回弹值并分析其特征,判断参考点选择是否合理,通过与其他参考点配准结果进行对比以及实验验证,验证回弹参考点选择方法的可行性。 展开更多
关键词 复杂型面零件 回弹参考点 逆向工程 修模量
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Estimation of the electromechanical characteristics of power systems based on a revised stochastic subspace method and the stabilization diagram 被引量:12
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作者 NI JingMin SHEN Chen LIU Feng 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第6期1677-1687,共11页
Estimating low-frequency oscillation modes and the corresponding mode shapes based on ambient data from WAMS measurements has a promising prospect in power system analysis and control.Based on the stochastic subspace ... Estimating low-frequency oscillation modes and the corresponding mode shapes based on ambient data from WAMS measurements has a promising prospect in power system analysis and control.Based on the stochastic subspace method,this paper proposes a revised stochastic subspace method by introducing reference channels,which can estimate the modes and the mode shapes simultaneously with great computational efficiency.Meanwhile,the accuracy of the estimated results is not degraded.To discriminate the real modes from the spurious ones,the stabilization diagram is introduced.A novel algorithm is designed to deal with the stabilization diagram which can detect the real modes automatically.Tests conducted on the IEEE-118 system indicate that the proposed method has good performance in terms of both computational efficiency and accuracy,and has the potential of being used on-line. 展开更多
关键词 electromechanical oscillation ambient data stochastic subspace method reference channels stabilization diagram
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Enclosure Fire-induced Temperature: Review and Model Modification for Horizontal Vented Space
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作者 ZHANG Jiaqing FAN Minghao +3 位作者 LI Wei DU Xiaofeng WU Haicheng WANG Shuping 《Journal of Thermal Science》 SCIE EI CAS CSCD 2015年第6期562-565,共4页
Correlations of fire-induced temperature have been reviewed and revisited.The impact of XY factors,i.e.,the relative locations of the fire source and vent,on temperature models of ceiling-vented compartments could be ... Correlations of fire-induced temperature have been reviewed and revisited.The impact of XY factors,i.e.,the relative locations of the fire source and vent,on temperature models of ceiling-vented compartments could be reflected by the exponents of the two dimensionless terms which represent the ratio of the total energy to energy released through the ceiling vent,and the ratio of the energy lost through the walls to the energy released through the ceiling vent.For fires not located directly below the ceiling vent,the temperature rise was proportional to two thirds of the power of the heat release rate,while for fires immediately beneath this vent,the temperature rise was proportional to four thirds the power of the heat release rate,and was inversely proportional to one sixth the power of the ceiling vent size. 展开更多
关键词 temperature model temperature rise compartment fire ceiling vent
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Self-consistency of a Modification Method Based on Membrane Model with Minimal Length Considered
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作者 Hao Tang Cheng-Yi Sun +2 位作者 Bin Wu Yu Song Rui-Hong Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第9期299-302,共4页
By adopting a result from generalized uncertainty principles (GUP), we modify the inner bound of the membrane model to a physical fixed value and get the cut-offs naturally rather than by hand, which are both in brick... By adopting a result from generalized uncertainty principles (GUP), we modify the inner bound of the membrane model to a physical fixed value and get the cut-offs naturally rather than by hand, which are both in brickwall model and membrane model, and the semi-classical quantization condition could always be valid as well. We also calculate the entropies of Schwarzschild-de Sitter black hole and find the GUP we choose qualitatively shows that the requirement of mass in this method is the same as the natural requirement of the Schwarzschild-de Sitter black hole,which means the method might be self-consistent. 展开更多
关键词 ENTROPY black hole generalized uncertainty principle brick-wall model membrane model
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Horava–Lifshitz Type Quantum Field Theory and Hierarchy Problem
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作者 晁伟 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第6期743-746,共4页
We study the Lifshitz type extension of the standard model(SM) at the UV, with dynamical critical exponent z = 3. One loop radiative corrections to the Higgs mass in such a model are calculated. Our result shows that,... We study the Lifshitz type extension of the standard model(SM) at the UV, with dynamical critical exponent z = 3. One loop radiative corrections to the Higgs mass in such a model are calculated. Our result shows that,the Hierarchy problem, which has initiated many excellent extension of the minimal SM, may be weakened in the z = 3 Lifshitz type quantum field theory. 展开更多
关键词 Lifshitz Hierarchy problem radiative corrections
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