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汉语数字的文化内涵--以○、一、二、三为例 认领
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作者 费燕洪 《林区教学》 2021年第2期107-110,共4页
数字是汉语、汉民族以及中华文化的重要组成部分,其内涵并不仅仅局限于数学计算。它是先民观察自然、探索自然的结果,是先哲思考、体悟宇宙自然、人事变换的成果,这在《周易》《道德经》等传统经典中都有所体现。对汉语数字进行研究,挖... 数字是汉语、汉民族以及中华文化的重要组成部分,其内涵并不仅仅局限于数学计算。它是先民观察自然、探索自然的结果,是先哲思考、体悟宇宙自然、人事变换的成果,这在《周易》《道德经》等传统经典中都有所体现。对汉语数字进行研究,挖掘其文化内涵是非常有意义的。以汉语中的○、一、二、三共四个数字为例,结合《周易》《道德经》《淮南子》等经典,探讨它们的文化内涵。 展开更多
关键词 数字 中华文化内涵
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Interaction effects on heat conduction and thermal stress in an infinite elastic plane with two circular holes 认领
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作者 Kun SONG Deshun YIN +1 位作者 Haibing YANG P.SCHIAVONE 《应用数学和力学:英文版》 SCIE EI 2021年第2期223-234,共12页
Numerous researches have focused on the physical behavior of an elastic material in the vicinity of a single hole under the assumption that the interaction effects arising from the introduction of multiple holes remai... Numerous researches have focused on the physical behavior of an elastic material in the vicinity of a single hole under the assumption that the interaction effects arising from the introduction of multiple holes remain negligible if the holes are placed sufficiently far from each other.In an effort to understand hole interaction effects on heat conduction and thermal stress,we consider the case when two circular holes are embedded in an infinite elastic material and use complex variable methods together with numerical analysis to obtain solutions describing temperature and elastic fields in the vicinity of the two circular holes.The results indicate that the interaction effects on temperature distribution and stress strongly depend on the relative size of the two holes and the distance placed between them but not on the actual size of the holes. 展开更多
关键词 heat conduction temperature field thermal stress interaction effect two circular holes
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Infl uence of sequential tropical cyclones on phytoplankton blooms in the northwestern South China Sea 认领
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作者 Tongyu WANG Shuwen ZHANG +3 位作者 Fajin CHEN Yonggui MA Chen JIANG Jie YU 《海洋湖沼学报(英文)》 SCIE CAS 2021年第1期14-25,共12页
Upper ocean responses to the passage of sequential tropical cyclones over the northwestern South China Sea(SCS)in 2011 were investigated using satellite remote sensing data,Argo reanalysis data,and an array of mooring... Upper ocean responses to the passage of sequential tropical cyclones over the northwestern South China Sea(SCS)in 2011 were investigated using satellite remote sensing data,Argo reanalysis data,and an array of mooring data.We found that the sea surface low temperature region lasted for more than 38 days and two phytoplankton blooms occurred after the passage of sequential tropical cyclones.The upper ocean cooling reached 2–5°C with a right-side bias was observed along the typhoon track to about 200 km.The maintenance of low temperature region and the two phytoplankton blooms were mainly driven by upwelling and near-inertial turbulence mixing induced by the sequential tropical cyclones.The fi rst phytoplankton bloom appeared on the 7 th day after the passage of the three tropical cyclones,and the chlorophyll-a(chl-a)concentration increased by 226%,which may be mainly driven by typhoons induced upwelling.The second phytoplankton bloom occurred on the 30 th day,the chl-a concentration increased by 290%.Further analysis suggested that only the typhoons with similar characteristics as Nesat and Nalgae can induce strong near-inertial oscillation(NIO).Strong turbulent mixing associated with the near-inertial baroclinic shear instability lasted for 26 days.The measured mean eddy diff usivity in the upper ocean was above 10-4 m 2/s after typhoon Nesat.Enhancement of the turbulent mixing in the upper ocean helped to transport nutrient-rich cold waters from the deep layer to the euphotic layer,and is a major mechanism for the long-term maintenance of low temperature region as well as the second phytoplankton bloom. 展开更多
关键词 sequential tropical cyclones two phytoplankton blooms tropical cyclones induced upwelling turbulence mixing by the near-inertial baroclinic shear instability
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Artificial Neural Network-based prediction of glacial debris flows in the ParlungZangbo Basin, southeastern Tibetan Plateau,China 认领
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作者 TANG Wang DING Hai-tao +4 位作者 CHEN Ning-sheng MA Shang-Chang LIU Li-hong WU Kang-lin TIAN Shu-feng 《山地科学学报:英文版》 SCIE 2021年第1期51-67,共17页
Accurate prediction on geological hazards can prevent disaster events in advance and greatly reduce property losses and life casualties.Glacial debris flows are the most serious hazards in southeastern Tibet in China ... Accurate prediction on geological hazards can prevent disaster events in advance and greatly reduce property losses and life casualties.Glacial debris flows are the most serious hazards in southeastern Tibet in China due to their complexity in formation mechanism and the difficulty in prediction.Data collected from 102 glacier debris flow events from 31 gullies since 1970 and regional meteorological data from 1970 to 2019 in ParlungZangbo River Basin in southeastern Tibet were used for Artificial Neural Network(ANN)-based prediction of glacial debris flows.The formation mechanism of glacial debris flows in the ParlungZangbo Basin was systematically analyzed,and the calculations involving the meteorological data and disaster events were conducted by using the statistical methods and two layers fully connected neural networks.The occurrence probabilities and scales of glacial debris flows(small,medium,and large)were predicted,and promising results have been achieved.Through the proposed model calculations,a prediction accuracy of 78.33%was achieved for the scale of glacial debris flows in the study area.The prediction accuracy for both large-and medium-scale debris flows are higher than that for small-scale debris flows.The debris flow scale and the probability of occurrence increase with increasing rainfall and temperature.In addition,the K-fold cross-validation method was used to verify the reliability of the model.The average accuracy of the model calculated under this method is about 93.3%,which validates the proposed model.Practices have proved that the combination of ANN and disaster events can provide sound prediction on geological hazards under complex conditions. 展开更多
关键词 Two layers neural networks Glacial debris flow Disaster events K-fold cross-validation RAINFALL Temperature
Comparative study of two fluid model and dense discrete phase model for simulations of gas-solid hydrodynamics in circulating fluidized beds 认领
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作者 Ying Wu Daoyin Liu +2 位作者 Jinding Hu Jiliang Ma Xiaoping Chen 《颗粒学报:英文版》 SCIE EI CAS 2021年第2期108-117,共10页
Computational fluid dynamics(CFD)has become a valuable tool to study the complex gas-solid hydrodynamics in the circulating fluidized bed(CFB).Based on the two fluid model(TFM)under the Eulerian-Eulerian framework and... Computational fluid dynamics(CFD)has become a valuable tool to study the complex gas-solid hydrodynamics in the circulating fluidized bed(CFB).Based on the two fluid model(TFM)under the Eulerian-Eulerian framework and the dense discrete phase model(DDPM)under the Eulerian-Lagrangian framework,this work conducts the comparative study of the gas-solid hydrodynamics in a CFB riser by these two different models.Results show that DDPM could be used to predict gas-solid hydrodynamics in the circulating fluidized bed,and there are differences between TFM and DDPM,especially in the radial distribution profiles of solid phase.Sensitivity analysis results show that the gas-solid drag model exhibits significant effects on the results for both the two models.The specularity coefficient and the restitution coefficient in the TFM,as well as the reflection coefficient and the parcel number in the DDPM,exhibit less impact on the simulated results. 展开更多
关键词 CFD simulation Circulating fluidized bed Gas-solid flow Two fluid model Dense discrete phase model
The Singular Integrals on the Intersection of Two Balls in C^(n) 认领
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作者 Dingdong GONG 《数学研究及应用:英文版》 2021年第1期49-61,共13页
In this paper the author studies the singular integral with the circularly deleted neighborhood on the boundary of the intersection of two balls, and obtain the principal value of the singular integral with holomorphi... In this paper the author studies the singular integral with the circularly deleted neighborhood on the boundary of the intersection of two balls, and obtain the principal value of the singular integral with holomorphic kernel and the Plemelj formula. 展开更多
关键词 intersection of two balls circularly deleted neighborhood principal value Plemelj formula
文章速递Safety of motorised two wheelers in mixed traffic conditions:Literature review of risk factors 认领
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作者 Jaikishan Damani Perumal Vedagiri 《交通运输工程学报:英文版》 CSCD 2021年第1期35-56,共22页
The ownership of motorised two wheelers(MTWs)has been on the rise across various countries across the globe.The growth has been especially higher in developing countries which have typical traffic characteristics and ... The ownership of motorised two wheelers(MTWs)has been on the rise across various countries across the globe.The growth has been especially higher in developing countries which have typical traffic characteristics and higher populations.This steady rise has resulted in increased accident and fatalities.This abrupt increase warranted attention from the researchers to carry out specific studies for MTWs,which have a very different behaviour as compared to cars in terms of physical and dynamic parameters.Moreover,the unique traffic patterns usually found in the developing countries pose an additional challenge to the researchers,since the conventional focus of transportation safety researchers was a homogeneous car-based traffic.Many such studies have been attempted,especially in the recent decades,which have considered various risk factors related to MTW safety.However,the studies have considered different sets of risk factors and have given surprising and even conflicting results.Therefore,a comprehensive review of the diverse studies needs to be carried out which incorporates all the risk factors considered in previous research.This study reviews such research papers which have analysed various risk factors related to safety of MTWs,especially in heterogeneous,non-lane based traffic.Specifically,this paper aims to incorporate results from those studies and highlight the conclusions from state of the art.The paper also discusses about the research gaps that are crucial for MTW safety in mixed traffic conditions.The review will be useful for researchers working in the field of MTW safety and for policy implementation and analysis. 展开更多
关键词 Traffic safety Motorised two wheelers Risk factors Driver behaviour Mixed traffic Non-lane based
Using Confidence Statements to Ordering Medians: A Simple Microarray Nonparametric Analysis 认领
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作者 Carlos A. de B. Pereira Adriano Polpo 《统计学期刊(英文)》 2020年第1期154-162,共9页
Comparing two samples about corresponding parameters of their respective populations is an old and classical statistical problem. In this paper, we present a simple yet effective tool to compare two samples through th... Comparing two samples about corresponding parameters of their respective populations is an old and classical statistical problem. In this paper, we present a simple yet effective tool to compare two samples through their medians. We calculate the confidence of the statement “the median of the first population is strictly smaller (larger) than the median of the second.” We analyze two real data sets and empirically demonstrate the quality of the confidence for such a statement. This confidence in the order of the medians is to be seen as a pre-analysis tool that can provide useful insights for comparing two or more populations. The method is entirely based on their exact distribution with no need for asymptotic considerations. We also provide the Quor statistical software, an R package that implements the ideas discussed in this work. 展开更多
关键词 Significance Test Comparison of Two Samples CONFIDENCE INTERVAL Based on the BINOMIAL Distribution
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Construction of <i>k</i>-Variate Survival Functions with Emphasis on the Case <i>k</i>= 3 认领
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作者 Jerzy K. Filus Lidia Z. Filus 《应用数学(英文)》 2020年第7期678-697,共20页
The purpose of this paper is to present a general universal formula for <span style="font-family:Verdana;"><i></i></span><i><span><span><i><span style="... The purpose of this paper is to present a general universal formula for <span style="font-family:Verdana;"><i></i></span><i><span><span><i><span style="font-family:Verdana;">k</span></i><span style="font-family:Verdana;"></span></span></span></i><span><span><span style="font-family:Verdana;">-variate survival functions for arbitrary </span><span style="font-family:Verdana;"><i></i></span></span></span><i><span><span><i><span style="font-family:Verdana;">k</span></i><span style="font-family:Verdana;"></span></span></span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> = 2, 3, </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">...</span><span style="font-family:Verdana;">, given all the univariate marginal survival functions. This universal form of </span></span><span style="font-family:Verdana;"><i></i></span></span></span><i><span><span><i><span style="font-family:Verdana;">k</span></i><span style="font-family:Verdana;"></span></span></span></i><span><span><span style="font-family:Verdana;">-variate probability distributions was obtained by means of “dependence functions” named “joiners” in the text. These joiners determine all the involved stochastic dependencies between the underlying random variables. However, in order that the presented formula (the form) represents a legitimate survival function, some necessary and sufficient conditions for the joiners had to be found. Basically, finding those conditions is the main task of this paper. This task was successfully performed for the case </span><span style="font-family:Verdana;"><i></i></span></span></span><i><span><span><i><span style="font-family:Verdana;">k</span></i><span style="font-family:Verdana;"></span></span></span></i><span><span><span style="font-family:Verdana;"> = 2 and the main results for the case </span><span style="font-family:Verdana;"><i></i></span></span></span><i><span><span><i><span style="font-family:Verdana;">k</span>< 展开更多
关键词 Construction of Multivariate Probability Distributions via Joiners Joiner versus Copula Methodology A Possible Fusion of the Two Construction Methods k -Variate Survival Function Scheme k = 3 Case
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A Solution to the Cosmological Constant Problem in Two Time Dimensions 认领
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作者 Christoph Köhn 《高能物理(英文)》 2020年第4期640-655,共16页
For the last hundred years, the existence and the value of the cosmological constant Λ has been a great enigma. So far, any theoretical model has failed to predict the value of Λ by several orders of magnitude. We h... For the last hundred years, the existence and the value of the cosmological constant Λ has been a great enigma. So far, any theoretical model has failed to predict the value of Λ by several orders of magnitude. We here offer a solution to the cosmological constant problem by extending the Einstein-Friedmann equations by one additional time dimension. Solving these equations, we find that the Universe is flat on a global scale and that the cosmological constant lies between 10<sup>-90</sup> m<sup>-2</sup> and 10<sup>-51</sup> m<sup>-2</sup> which is in range observed by experiments. It also proposes a mean to explain the Planck length and to mitigate the singularity at the Big Bang. 展开更多
关键词 Two Time Dimensions Planck Length Cosmological Constant Problem Curvature of the Universe
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Using Refined Theory to Studied Elastic Wave Scattering and Dynamic Stress Concentrations in Plates with Two Cutouts 认领
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作者 Xujiao Yang Zihe Li Haoyu Liu 《应用数学与应用物理(英文)》 2020年第12期2999-3018,共20页
In this paper, based on complex variables and conformal mapping methods, using the refined dynamic equation of plates, elastic wave scattering and dynamic stress concentrations in plates with two cutouts were studied.... In this paper, based on complex variables and conformal mapping methods, using the refined dynamic equation of plates, elastic wave scattering and dynamic stress concentrations in plates with two cutouts were studied. Applying the orthogonal function expansion method, the problem to be solved can be reduced into the solution of a set of infinite algebraic equations. According to free boundary conditions, numerical results of dynamic moment concentration factors in thick plates with two circular cutouts analyze that: there will be more complex interaction changes between two-cutout situation than single cutout situation. In the case of low frequency or high frequency and thin plate, the hole-spacing in the absence of coupling interactions was larger or smaller. The numerical results and method can be used to analyze the dynamics and strength of plate-like structures. 展开更多
关键词 Refined Vibration Equation of Plate Bending Complex Variable and Conformal Mapping Method Two Holes Elastic Wave Scattering and Dynamic Stress Concentrations
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Relativistic Reduction of the Electron-Nucleus Force in Bohr’s Hydrogen Atom and the Time of Electron Transition between the Neighbouring Quantum Energy Levels 认领
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作者 Stanisław Olszewski 《现代物理(英文)》 2020年第6期944-951,共8页
The aim of the paper is to get an insight into the time interval of electron emission done between two neighbouring energy levels of the hydrogen atom. To this purpose, in the first step, the formulae of the special r... The aim of the paper is to get an insight into the time interval of electron emission done between two neighbouring energy levels of the hydrogen atom. To this purpose, in the first step, the formulae of the special relativity are applied to demonstrate the conditions which can annihilate the electrostatic force acting between the nucleus and electron in the atom. This result is obtained when a suitable electron speed entering the Lorentz transformation is combined with the strength of the magnetic field acting normally to the electron orbit in the atom. In the next step, the Maxwell equation characterizing the electromotive force is applied to calculate the time interval connected with the change of the magnetic field necessary to produce the force. It is shown that the time interval obtained from the Maxwell equation, multiplied by the energy change of two neighbouring energy levels considered in the atom, does satisfy the Joule-Lenz formula associated with the quantum electron energy emission rate between the levels. 展开更多
关键词 Hydrogen Atom The Bohr Model Lorentz Transformation Done with the Aid of the Electron Orbital Speed Maxwell Equation Applied to Calculate the Time Interval of Electron Transitions between Two Quantum Energy Levels Comparison with the Joule-Lenz Law for Energy Emission
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Persistent Hiccups Following Use of Oral Dexamethasone: A Report of Two Cases from Abakaliki, Nigeria 认领
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作者 Chukwuemeka O. Eze Thomas O. Nnaji Monday U. Nwobodo 《临床医学病理报告(英文)》 2020年第9期282-287,共6页
Hiccups are common, usually mild with no obvious cause and often resolve spontaneously. They are classified as transient, persistent and intractable depending on the duration. Drug induced hiccups have been reported i... Hiccups are common, usually mild with no obvious cause and often resolve spontaneously. They are classified as transient, persistent and intractable depending on the duration. Drug induced hiccups have been reported in medical literature but not common and corticosteroids are often cited. This report involved 2 male patients who developed persistent hiccups following use of oral dexamethasone for inflammatory conditions. The hiccups were severe and intolerable and could not stop despite use of metoclopramide and chlorpromazine. The hiccups only stopped following discontinuation of the dexamethasone. It should be noted that low dose of dexamethasone was used. Management of dexamethasone induced hiccups involves discontinuation of the drug, steroid rotation if the patient is steroid dependent and use of metoclopramide and chlorpromazine. Clinicians should be aware of this known but rare adverse effect of dexamethasone as it could be severe, distressful and negatively impart patients care. There is a need for a high index of suspicion whenever a patient develops hiccups while taking dexamethasone. 展开更多
关键词 Persistent Hiccups Following Use of Oral Dexamethasone: A Report of Two Cases from Abakaliki NIGERIA
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Numerical Study of the Lift Force, Velocities and Pressure Distribution of a Single Air Bubble and Two Interacting Air Bubbles Rising in Quiescent Liquid 认领
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作者 Chao Guan Shinichiro Yanase +2 位作者 Koji Matsuura Toshinori Kouchi Yasunori Nagata 《流体动力学(英文)》 2020年第1期31-51,共21页
The study of multiphase flow consisting of liquid and air bubbles has been attracting the interest of many researchers. Numerical methods for such a system are, however, facing difficulty in numerical accuracy and a h... The study of multiphase flow consisting of liquid and air bubbles has been attracting the interest of many researchers. Numerical methods for such a system are, however, facing difficulty in numerical accuracy and a heavy computational load. In this paper, we made corrections to the modified force-coupling method in our previous papers and applied it to the numerical studies of a single air bubble rising near a vertical wall and two interacting air bubbles rising in line in quiescent liquid. Corrections were made to the effective ranges of the force-coupling method. The calculation results showed that the lift force acting on an air bubble obtained by the experimental data was more accurately reproduced than those by our previous method. We accurately calculated the time evolution of the velocities of interacting two air bubbles rising in line obtained in the previous experiments and resolved the physical mechanism of the relative movement of two bubbles. We also found the present method is much quicker and needs much smaller memory capacity than other methods, such as the volume of fluid method. 展开更多
关键词 Force-Coupling Method MULTIPHASE Flow BUBBLE Motion Two BUBBLE Interaction
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Method of Lines for the Chiral Nonlinear Schrödinger Equation 认领
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作者 K. S. AL-Basyouni M. S. Ismail 《应用数学(英文)》 2020年第6期447-459,共13页
In this paper, we solve chiral nonlinear Schrodinger equation (CNSE) numerically. Two numerical methods are derived using the explicit Runge-Kutta method of order four and the linear multistep method (Predictor-Correc... In this paper, we solve chiral nonlinear Schrodinger equation (CNSE) numerically. Two numerical methods are derived using the explicit Runge-Kutta method of order four and the linear multistep method (Predictor-Corrector method of fourth order). The resulting schemes of fourth order accuracy in spatial and temporal directions. The CNSE is non-integrable and has two kinds of soliton solutions: bright and dark soliton. The exact solutions and the conserved quantities of CNSE are used to display the efficiency and robustness of the numerical methods we derived. Interaction of two bright solitons for different parameters is also displayed. 展开更多
关键词 Method of Lines Linear Multistep Method Chiral Soliton Interaction of Two Solitons
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Impact of Chloride Channel on Spiking Patterns of Morris-Lecar Model 认领
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作者 Tahmineh Azizi Bacim Alali 《应用数学(英文)》 2020年第7期650-669,共20页
In this paper,we study the complicated dynamics of general Morris-Lecar model with the impact of Cl<sup>-</sup> fluctuations on firing patterns of this neuron model. After adding Cl<sup>-</sup>... In this paper,we study the complicated dynamics of general Morris-Lecar model with the impact of Cl<sup>-</sup> fluctuations on firing patterns of this neuron model. After adding Cl<sup>-</sup> channel in the original Morris-Lecar model, the dynamics of the original model such as its bifurcations of equilibrium points would be changed and they occurred at different values compared to the primary model. We discover these qualitative changes in the point of dynamical systems and neuroscience. We will conduct the co-dimension two bifurcations analysis with respect to different control parameters to explore the complicated behaviors for this new neuron model. 展开更多
关键词 Chloride Channel Supercritical Hopf Bifurcation Subcritical Hopf Bifurcation Firing Spike Co-Dimension Two Bifurcations
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The Pioneer Effect: A New Physics with a New Principle 认领
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作者 Russell Bagdoo 《现代物理(英文)》 2020年第5期616-647,共32页
Radiometric data from the Pioneer 10/11, Galileo and Ulysses spacecraft indicated an anomalous constant acceleration acting on them, directed toward the Sun, and a gradual growth of the radio signal frequency emitted ... Radiometric data from the Pioneer 10/11, Galileo and Ulysses spacecraft indicated an anomalous constant acceleration acting on them, directed toward the Sun, and a gradual growth of the radio signal frequency emitted by the receding transmitter. The reported odd acceleration of Pioneer 10 with a magnitude?&sim;8.5 × 10&minus;10 m/s2 can be explained by an induced gravitational interaction on the S-band signals traveling between the probe and the Earth, arising from the electromagnetic properties of the outer Solar System vacuum zero-point radiation interacting with matter. Their nature is of quantum vacuum origin, and these induced forces act in addition to ordinary gravitational forces, violating the principle of Equivalence. We suggest a new physical theory based on a new principle called “Compensation” as a thinkable explanation for the non-conventional Pioneer effect. The theory of Relation, which is an alternative to the inflationist model, postulates that our universe is made of two antagonistic but complementary structures. The principle of Compensation contradicts Relativity theory, predicts such acceleration and is for the electromagnetic spacetime metric what the principle of Equivalence is for the gravific spacetime metric. 展开更多
关键词 Theory of Relation PRINCIPLE of COMPENSATION Two Structures Negative EM WAVELENGTH of SPACETIME ZERO Point FLUCTUATIONS
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The“Two Sessions”and China's actions for recovery 认领
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《中国标准化:英文版》 2020年第4期4-5,共2页
How will China recover from the pandemic crisis in the post-Covid era? What role do standards play to address risks? The July/August issue of China Standardization presents the highlights of this year’s "Two Ses... How will China recover from the pandemic crisis in the post-Covid era? What role do standards play to address risks? The July/August issue of China Standardization presents the highlights of this year’s "Two Sessions", the landmark Civil Code and three pivotal standards helping the epidemic control and risk management. 展开更多
关键词 SESSION HELPING TWO
Development Situations and Countermeasures of Gastrodia elata Industry in Zhaotong City 认领
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作者 Xuewei ZHU Qifa LI Yujie HE 《亚洲农业研究:英文版》 2020年第9期28-29,32,共3页
With the rapid development of technology,people's living standards have been greatly improved,and more and more people have started to care more about the theory and health preservation function of TCM.Gastrodia e... With the rapid development of technology,people's living standards have been greatly improved,and more and more people have started to care more about the theory and health preservation function of TCM.Gastrodia elata,as a precious Chinese herbal medicine,is harmless to human health.Due to the high economic benefits and real benefits for farmers,the G.elata industry has developed rapidly.Zhaotong is the hometown of G.elata f.glauca in China,but the current situation of the G.elata industry lags behind other producing areas.Through field survey and literature review,this paper comprehensively analyzed the development status of the G.elata industry in Zhaotong City.Combined with the natural conditions,policy conditions,and socio-economic conditions of the G.elata industry in Zhaotong City to find countermeasures and recommendations to promote the further development of the G.elata industry in Zhaotong and provide recommendations for the sustainable development of G.elata industry. 展开更多
关键词 Gastrodia elata in Zhaotong Current situations of Gastrodia elata industry Two varieties of bacteria planting
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Growth of Single-crystalline Transition Metal Dichalcogenides Monolayers with Large-size 认领
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作者 ZHOU Shcngxuc JIAO Liying 《高等学校化学研究:英文版》 SCIE CAS CSCD 2020年第4期511-517,共7页
Two-dimensional(2D)transition metal dichalcogenides(TMDCs)semiconductors,such as monolayers of molybdenum disulfide(MoS2)and tungsten disulfide(WS2)can potentially serve as ultrathin channel materials for building sho... Two-dimensional(2D)transition metal dichalcogenides(TMDCs)semiconductors,such as monolayers of molybdenum disulfide(MoS2)and tungsten disulfide(WS2)can potentially serve as ultrathin channel materials for building short channel field-eflect transistors(FETs)to further extend Moore's Law.It is essential to develop controllable approaches for the syntliesis of large single crystals of these 2D semiconductors to promote their practical applications in future electronics.In this short review,we summarized the recent advances on the chemical vapor deposition(CVD)of single crystalline semiconducting 2D TMDCs with a large size.We first discussed the driving force and urgent demands on developing controllable approaches for the growth oflarge 2D TMDCs single crystals and then summarized the current strategies and representative studies on the CVD growth of large 2D single crystals.Finally,we discussed the challenges and future directions in this topic. 展开更多
关键词 Two dimensional Single crystal Chemical vapor deposition Field effect transistor
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