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Estimation of fracture size and azimuth in the universal elliptical disc model based on trace information 被引量:2
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作者 Jichao Guo Jun Zheng +1 位作者 Qing Lü Jianhui Deng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第6期1391-1405,共15页
The geometric characteristics of fractures within a rock mass can be inferred by the data sampling from boreholes or exposed surfaces.Recently,the universal elliptical disc(UED)model was developed to represent natural... The geometric characteristics of fractures within a rock mass can be inferred by the data sampling from boreholes or exposed surfaces.Recently,the universal elliptical disc(UED)model was developed to represent natural fractures,where the fracture is assumed to be an elliptical disc and the fracture orientation,rotation angle,length of the long axis and ratio of short-long axis lengths are considered as variables.This paper aims to estimate the fracture size-and azimuth-related parameters in the UED model based on the trace information from sampling windows.The stereological relationship between the trace length,size-and azimuth-related parameters of the UED model was established,and the formulae of the mean value and standard deviation of trace length were proposed.The proposed formulae were validated via the Monte Carlo simulations with less than 5%of error rate between the calculated and true values.With respect to the estimation of the size-and azimuth-related parameters using the trace length,an optimization method was developed based on the pre-assumed size and azimuth distribution forms.A hypothetical case study was designed to illustrate and verify the parameter estimation method,where three combinations of the sampling windows were used to estimate the parameters,and the results showed that the estimated values could agree well with the true values.Furthermore,a hypothetical three-dimensional(3D)elliptical fracture network was constructed,and the circular disc,non-UED and UED models were used to represent it.The simulated trace information from different models was compared,and the results clearly illustrated the superiority of the proposed UED model over the existing circular disc and non-UED models。 展开更多
关键词 universal elliptical disc(UED)model Rock mass Discrete fracture network(DFN) Optimization algorithm Inverse problem
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Dark Matter and Dark Energy from Lattice Model of Universe
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作者 Branislav Majerník 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1045-1053,共9页
The article considers a conceptual universe model as a periodic lattice (network) with nodes defined by the wave function in a background-independent Hamiltonian based on their relations and interactions. This model g... The article considers a conceptual universe model as a periodic lattice (network) with nodes defined by the wave function in a background-independent Hamiltonian based on their relations and interactions. This model gives rise to energy bands, similar to those in semiconductor solid-state models. In this context, valence band holes are described as dark matter particles with a heavy effective mass. The conducting band, with a spontaneously symmetry-breaking energy profile, contains particles with several times lighter effective mass, which can represent luminous matter. Some possible analogies with solid-state physics, such as the comparison between dark and luminous matter, are discussed. Additionally, tiny dark energy, as intrinsic lattice Casimir energy, is calculated for a lattice with a large number of lattice nodes. 展开更多
关键词 Dark Energy Dark Matter Lattice Universe model
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Solving the Olbers’s Paradox, Explaining the “Red-Shift”, and Challenging the Relativities by “Sun Matters Theory” and “Sun Model of Universe”, an Evolution of the Einstein’s Static Universe Model
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作者 Wanpeng Sun 《Natural Science》 2024年第2期7-18,共12页
Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used ... Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used to partially explain this paradox, while introducing new problems. Hereby, we propose a better theory, named Sun Matters Theory, to explain this paradox. Moreover, this unique theory supports and extended the Einstein’s static universe model proposed by Albert Einstein in 1917. Further, we proposed our new universe model, “Sun Model of Universe”. Based on the new model and novel theory, we generated innovative field equation by upgrading Einstein’s Field Equation through adding back the cosmological constant, introducing a new variable and modifying the gravitationally-related concepts. According to the Sun Model of Universe, the dark matter and dark energy comprise the so-called “Sun Matters”. The observed phenomenon like the red shift is explained as due to the interaction of ordinary light with Sun Matters leading to its energy and frequency decrease. In Sun Model, our big universe consists of many universes with ordinary matter at the core mixed and surrounded with the Sun Matters. In those universes, the laws of physics may be completely or partially different from that of our ordinary universe with parallel civilizations. The darkness of night can be easily explained as resulting from the interaction of light with the Sun Matters leading to the sharp decrease in the light intensity. Sun Matters also scatter the light from a star, which makes it shining as observed by Hubble. Further, there is a kind of Sun Matters named “Sun Waters”, surrounding every starts. When lights pass by the sun, the Sun Waters deflect the lights to bend the light path. According to the Sun Model, it is the light bent not the space bent that was proposed in the theory of relativities. 展开更多
关键词 Olbers’s Paradox Sun Matters Theory Sun model of Universe Einstein’s Universe Dark Mass
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Hubble Tension Explanation from This Cosmological Model AΛΩ (Slow Bang Model, SB)
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作者 Jean Perron 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期106-125,共20页
In this article we present a model of Hubble-Lemaître law using the notions of a transmitter (galaxy) and a receiver (MW) coupled to a model of the universe (Slow Bang Model, SB), based on a quantum approach of t... In this article we present a model of Hubble-Lemaître law using the notions of a transmitter (galaxy) and a receiver (MW) coupled to a model of the universe (Slow Bang Model, SB), based on a quantum approach of the evolution of space-time as well as an equation of state that retains all the infinitesimal terms. We find an explanation of the Hubble tension H<sub>0</sub>. Indeed, we have seen that this constant depends on the transceiver pair which can vary from the lowest observable value, from photons of the CMB (theoretical [km/s/Mpc]) to increasingly higher values depending on the earlier origin of the formation of the observed galaxy or cluster (ETG ~0.3 [Gy], ~74 [km/s/Mpc]). We have produced a theoretical table of the values of the constant according to the possible pairs of transmitter/receiver in the case where these galaxies follow the Hubble flow without large disturbance. The calculated theoretical values of the constant are in the order of magnitude of all values mentioned in past studies. Subsequently, we applied the models to 9 galaxies and COMA cluster and found that the models predict acceptable values of their distances and Hubble constant since these galaxies mainly follow the Hubble flow rather than the effects of a galaxy cluster or a group of clusters. In conclusion, we affirm that this Hubble tension does not really exist and it is rather the understanding of the meaning of this constant that is questioned. 展开更多
关键词 model of the Universe Cosmological Constant Hubble Constant Hubble’s Tension Hubble-Lemaître Law Hubble’s Flow
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The establishment and evaluation of near infrared universal model to determinate the effective ingredient content in pesticide rapidly 被引量:3
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作者 Yan Mei Xiong Xiang Zhong Song +5 位作者 Chang Zhou Chen Hong Ping Lin Guo Tang Yue Huang Jia Duan Shun Geng Min 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第9期1047-1050,共4页
A near infrared universal quantitative analysis model was established to determinate the effective ingredient content in pesticide EC (hikemalisation) by the PLS (partial least squares) algorithm, the model predic... A near infrared universal quantitative analysis model was established to determinate the effective ingredient content in pesticide EC (hikemalisation) by the PLS (partial least squares) algorithm, the model predictive ability was evaluated by the external inspection method. The model was established among samples containing the same active ingredient from five different companies, and the model determination coefficient R2 and RMSECV (root mean square error of cross validation) were 0.9997 and 0.0223, respectively, the relative error between predicted value and chemical value of the testing set samples was between -2.71% and 3.36%, which indicated that the method to determinate the effective ingredient content in pesticide EC by the established universal model can meet the need of pesticide market monitoring. 展开更多
关键词 Near infrared spectroscopy Pesticide EC Quantitative analysis universal model
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Combining RUSLE model and the vegetation health index to unravel the relationship between soil erosion and droughts in southeastern Tunisia 被引量:1
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作者 Olfa TERWAYET BAYOULI ZHANG Wanchang Houssem TERWAYET BAYOULI 《Journal of Arid Land》 SCIE CSCD 2023年第11期1269-1289,共21页
Droughts and soil erosion are among the most prominent climatic driven hazards in drylands,leading to detrimental environmental impacts,such as degraded lands,deteriorated ecosystem services and biodiversity,and incre... Droughts and soil erosion are among the most prominent climatic driven hazards in drylands,leading to detrimental environmental impacts,such as degraded lands,deteriorated ecosystem services and biodiversity,and increased greenhouse gas emissions.In response to the current lack of studies combining drought conditions and soil erosion processes,in this study,we developed a comprehensive Geographic Information System(GIS)-based approach to assess soil erosion and droughts,thereby revealing the relationship between soil erosion and droughts under an arid climate.The vegetation condition index(VCI)and temperature condition index(TCI)derived respectively from the enhanced vegetation index(EVI)MOD13A2 and land surface temperature(LST)MOD11A2 products were combined to generate the vegetation health index(VHI).The VHI has been conceived as an efficient tool to monitor droughts in the Negueb watershed,southeastern Tunisia.The revised universal soil loss equation(RUSLE)model was applied to quantitatively estimate soil erosion.The relationship between soil erosion and droughts was investigated through Pearson correlation.Results exhibited that the Negueb watershed experienced recurrent mild to extreme drought during 2000–2016.The average soil erosion rate was determined to be 1.8 t/(hm2•a).The mountainous western part of the watershed was the most vulnerable not only to soil erosion but also to droughts.The slope length and steepness factor was shown to be the most significant controlling parameter driving soil erosion.The relationship between droughts and soil erosion had a positive correlation(r=0.3);however,the correlation was highly varied spatially across the watershed.Drought was linked to soil erosion in the Negueb watershed.The current study provides insight for natural disaster risk assessment,land managers,and stake-holders to apply appropriate management measures to promote sustainable development goals in fragile environments. 展开更多
关键词 DROUGHTS soil erosion vegetation health index(VHI) revised universal soil loss equation(RUSLE)model southeastern Tunisia
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MODELING AND CONTROL OF A UNIVERSAL PART FEEDER
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作者 Du Winncy 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期317-320,共4页
The modeling and motion control of a universal part feeder is addressed. The feeder consists of a flat plate (or called bed) and a part placed on the plate. The bed can vibrate side-by-side (in x axis), back and f... The modeling and motion control of a universal part feeder is addressed. The feeder consists of a flat plate (or called bed) and a part placed on the plate. The bed can vibrate side-by-side (in x axis), back and forth (in y axis), clockwise and counter clockwise (about z axis), actuated by three linear motors (voice coils). When the bed does these vibrations, the part placed on the plat will have position and/or orientation change due to the interaction between the two contact surfaces. By controlling the ways in which the plate vibrates, the position and orientation of the part can be controlled. The two vibration profiles of the bed are investigated in the research: the high-low vibration mode and the bang-bang vibration mode. The motion equations of the bed and the part as well as the control schemes for the high-low vibration mode are presented. Both simulation and real-time testing verify the system's dynamic model and indicate the feasibilities of the developed control laws. 展开更多
关键词 universal part feeder (UPF) Vibratory parts feeder modeling and control
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ETG Galaxies (<400 [My]) from JWST Already Predicted in 2019 from This Cosmological Model AΛΩ (Slow Bang Model, SB)
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作者 Jean Perron 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第3期800-834,共35页
A model of the universe (preprint 2019), based on a quantum approach to the evolution of space-time as well as on an equation of state that retains all the infinitesimal terms, has made it possible to estimate a large... A model of the universe (preprint 2019), based on a quantum approach to the evolution of space-time as well as on an equation of state that retains all the infinitesimal terms, has made it possible to estimate a large number of parameters relating to the universe and in particular the estimation of a colossal phantom energy E<sub>Λ</sub> represented by the existence of a hidden photon &ycirc;present everywhere. This energy undergoes dilution in H<sup>4</sup> due to expansion of the universe. In order to introduce the effects of this energy on the curvature of space-time, we chose to express it by the cosmological constant Λ in the equation of the GR via the element tensor T<sup>00</sup>. This positive energy E<sub>Λ</sub> which acts as additional effect to gravity and we have expressed this energy in the form of an equation which expresses a so-called cosmological force F<sub>Λ</sub>. We estimated that this photon or hidden particle of spin 1 has an energy ~1 [meV] at our cosmic position t<sub>0</sub> which makes it an ultra-light axion ULA. Subsequently, with the action of this augmented force, especially in the first 400 [My] we were able to explain, in part, the rapid development of galaxy formation as seen by JWST as well as several observed dynamic behaviors of the barionic mass of some galaxies as MW, M33, UGC12591, NGC3198, UGC2885 and NGC253 whose observations raise questions and require additional explanations that led to the likely existence of unobserved matter called DM. However, it appears that this cosmological force makes it possible to explain several observations without the use of this DM. A first conclusion was drawn, namely the much earlier formation of galaxies by the action of this cosmological force coupled with gravity (GLASS z12). In addition, the model made it possible to explain the need or not to use the concept of DM for ETGs and LTGs by the more or less early and long period of the beginning of galaxy formation over a period ranging from ~170 to 1200 [My]. Thus, the model makes it possible to explain to a large extent the observations of the dynamics of the galaxies studied. However, several questions remain. 展开更多
关键词 model of Universe ETG LTG UDG Cosmological Constant Hidden Photon Hidden Boson GLASS z12
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Non-negligible factors in low-pressure sprinkler irrigation:droplet impact angle and shear stress
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作者 HUI Xin ZHENG Yudong +2 位作者 MUHAMMAD Rizwan Shoukat TAN Haibin YAN Haijun 《Journal of Arid Land》 SCIE CSCD 2022年第11期1293-1316,共24页
Droplet shear stress is considered as an important indicator that reflects soil erosion in sprinkler irrigation more accurately than kinetic energy,and the effect of droplet impact angle on the shear stress cannot be ... Droplet shear stress is considered as an important indicator that reflects soil erosion in sprinkler irrigation more accurately than kinetic energy,and the effect of droplet impact angle on the shear stress cannot be ignored.In this study,radial distribution of droplet impact angles,velocities,and shear stresses were investigated using a two-dimensional video disdrometer with three types of low-pressure sprinkler(Nelson D3000,R3000,and Komet KPT)under two operating pressures(103 and 138 kPa)and three nozzle diameters(3.97,5.95,and 7.94 mm).Furthermore,the relationships among these characteristical parameters of droplet were analyzed,and their influencing factors were comprehensively evaluated.For various types of sprinkler,operating pressures,and nozzle diameters,the smaller impact angles and larger velocities of droplets were found to occur closer to the sprinkler,resulting in relatively low droplet shear stresses.The increase in distance from the sprinkler caused the droplet impact angle to decrease and velocity to increase,which contributed to a significant increase in the shear stress that reached the peak value at the end of the jet.Therefore,the end of the jet was the most prone to soil erosion in the radial direction,and the soil erosion in sprinkler irrigation could not only be attributed to the droplet kinetic energy,but also needed to be combined with the analysis of its shear stress.Through comparing the radial distributions of average droplet shear stresses among the three types of sprinklers,D3000 exhibited the largest value(26.94-3313.51 N/m^(2)),followed by R3000(33.34-2650.80 N/m^(2)),and KPT(16.15-2485.69 N/m^(2)).From the perspective of minimizing the risk of soil erosion,KPT sprinkler was more suitable for low-pressure sprinkler irrigation than D3000 and R3000 sprinklers.In addition to selecting the appropriate sprinkler type to reduce the droplet shear stress,a suitable sprinkler spacing could also provide acceptable results,because the distance from the sprinkler exhibited a highly significant(P<0.01)effect on the shear stress.This study results provide a new reference for the design of low-pressure sprinkler irrigation system. 展开更多
关键词 center pivot irrigation system water droplet universal model soil erosion water-saving irrigation
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EMOTIONAL SPEECH RECOGNITION BASED ON SVM WITH GMM SUPERVECTOR 被引量:1
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作者 Chen Yanxiang Xie Jian 《Journal of Electronics(China)》 2012年第3期339-344,共6页
Emotion recognition from speech is an important field of research in human computer interaction. In this letter the framework of Support Vector Machines (SVM) with Gaussian Mixture Model (GMM) supervector is introduce... Emotion recognition from speech is an important field of research in human computer interaction. In this letter the framework of Support Vector Machines (SVM) with Gaussian Mixture Model (GMM) supervector is introduced for emotional speech recognition. Because of the importance of variance in reflecting the distribution of speech, the normalized mean vectors potential to exploit the information from the variance are adopted to form the GMM supervector. Comparative experiments from five aspects are conducted to study their corresponding effect to system performance. The experiment results, which indicate that the influence of number of mixtures is strong as well as influence of duration is weak, provide basis for the train set selection of Universal Background Model (UBM). 展开更多
关键词 Emotional speech recognition Support Vector Machines (SVM) Gaussian Mixture model (GMM) supervector universal Background model (USB)
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Research of whispered speech vocal tract system conversion based on universal background model and effective Gaussian components 被引量:1
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作者 CHEN Xueqin ZHAO Heming 《Chinese Journal of Acoustics》 2013年第4期400-410,共11页
Directing to the weakness of the present fixed values mapping methods (method_F), a vocal tract system conversion method based on the universal background model (UBM) is proposed for improving the performance of t... Directing to the weakness of the present fixed values mapping methods (method_F), a vocal tract system conversion method based on the universal background model (UBM) is proposed for improving the performance of the speech conversion system from Chinese whis- pered speech to normal speech. For the numerous components of UBM, the errors produced by the acoustical probability density statistical model can't be ignored. Thus an effective Gaus- sian mixture components chosen method based on the posterior probability summation of the minimum spectral distortion is developed to optimizing the system performance. The proposed method (method_U) is analyzed and compared using the performance index (PI) based on Itakura-Saito spectral distortion measure. It is shown experimentally that the performance of method_U is more stability for different speakers and different phonemes than that of method_F. The average PI of method_U is better than method_F. It is shown that by selecting effective Gaussian mixture components, the PI of method_U can be further improved 5.11%. Subjective auditory tests also show that the proposed method can improve the definition and intelligibility of conversion speech. 展开更多
关键词 Research of whispered speech vocal tract system conversion based on universal background model and effective Gaussian components UBM
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Predicting the Curvature of the Cosmos, and Point of Volume Contraction in a Big Bounce Scenario
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作者 Christopher Pilot 《International Journal of Astronomy and Astrophysics》 2021年第2期265-278,共14页
Based on the latest Planck surveys, the universe is close to being remarkably flat, and yet, within observational error, there is still room for a slight curvature. If the curvature is positive, then this would lead t... Based on the latest Planck surveys, the universe is close to being remarkably flat, and yet, within observational error, there is still room for a slight curvature. If the curvature is positive, then this would lead to a closed universe, as well as allow for a big bounce scenario. Working within these assumptions, and using a simple model, we predict that the cosmos may have a positive curvature in the amount, <span style="white-space:nowrap;"><span style="white-space:nowrap;">Ω<sub>0</sub>=1.001802</span></span>, a value within current observational bounds. For the scaling laws associated with the density parameters in Friedmann’s equations, we will assume a susceptibility model for space, where, <img src="Edit_18751d6f-dbfa-47ba-be7c-8298073a34fd.png" alt="" style="white-space:normal;" />, equals the smeared cosmic susceptibility. If we allow the <img src="Edit_18751d6f-dbfa-47ba-be7c-8298073a34fd.png" alt="" /> to <em>decrease with increasing</em> cosmic scale parameter, “<em>a</em>”, then we can predict a maximum Hubble volume, with minimum CMB temperature for the voids, before contraction begins, as well as a minimum volume, with maximum CMB temperature, when expansion starts. A specific heat engine model for the cosmos is also entertained for this model of a closed universe. 展开更多
关键词 Cosmic Curvature Closed Universe Cyclic Universe Heat Engine model for Universe Big Bounce Susceptibility model for Universe Carnot Cycle model for Cosmos Causal Isotropy in CMB Temperature
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Suggestions and Reflections on Inheritance Strategy of Traditional Residence Construction Technique of Ethnic Minorities in Western Hubei
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作者 SONG Zheng 《Journal of Landscape Research》 2022年第5期32-38,42,共8页
The traditional residence of ethnic minorities in western Hubei has a long history,and their construction skills reflect the wisdom and culture of the nation.Due to the limitation of geographical environment,the devel... The traditional residence of ethnic minorities in western Hubei has a long history,and their construction skills reflect the wisdom and culture of the nation.Due to the limitation of geographical environment,the development of modern cities and towns,and the influence of foreign culture,the inheritance of traditional construction skills is facing a great crisis.This paper analyzes the research status of traditional residence of ethnic minorities and summarizes the necessity of inheriting the traditional residence construction technique.Moreover,strategies and suggestions about inheritance are put forward from four aspects:the national policy guidance and local implementation,building characteristic area of traditional residence,establishing and improving the theoretical framework of building skills,and building digital platform.The ways and methods of integrating traditional construction skills and culture into the training process of colleges and universities are explored. 展开更多
关键词 Traditional residence of ethnic minorities Traditional construction skills Strategies and suggestions of inheritance Inheritance model of colleges and universities
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Triple-Polarized Multi-User Mimo-Idma System under Correlated Fading Channel
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作者 B. Partibane V. Nagarajan 《Circuits and Systems》 2016年第8期1623-1634,共12页
A multiple-input multiple-output interleave division multiple access (MIMO-IDMA) system with Triple Polarized Division Multiplexing (TPDM) is presented in this paper. The present methodology replaces three indepe... A multiple-input multiple-output interleave division multiple access (MIMO-IDMA) system with Triple Polarized Division Multiplexing (TPDM) is presented in this paper. The present methodology replaces three independent linearly polarized antennas with a single triple polarized antenna at both the transmitter and receiver. The users in the communication link are accommodated and separated using a user-specific interleaver combined with low rate spreading sequence. To eliminate the effects of multi-stream interference (MSI), minimum mean square error (MMSE) algorithm based on successive interference cancellation (SIC) Multi-user detection (MUD) technique is employed at the receiver. Furthermore, log-maximum a posteriori probability (MAPP) decoding algorithm is implemented at the mobile stations (MSs) to overcome the effects of multi-user interference (MUI) effects. The paper also evaluates the effects of coded MIMO-IDMA in the downlink communication by adopting the Stanford University Interim (SUI) and Long-term Evolution (LTE)channel model specifications. In comparison with the traditional uncoded system, the present solution considering turbo coded triple-polarized MIMO-IDMA system with iterative decoding algorithm provides better bit error rate (BER) with reduced signal to noise ratio (SNR). The simulation results also show that though the SNR requirement is higher for the proposed technique compared to the conventional uni-polarized antenna based MIMO-IDMA system, it gives the advantages of achieving higher data rate with reduced cost and space requirements in the context of a downlink (DL). 展开更多
关键词 Interleave Division Multiple Access (IDMA) Multiple Input Multiple Output (MIMO) Multi-User Interference (MUI) Stanford University Interim (SUI) Channel model Long Term Evolution (LTE) Channel model
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Universal materials model of deep-learning density functional theory Hamiltonian
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作者 Yuxiang Wang Yang Li +14 位作者 Zechen Tang He Li Zilong Yuan Honggeng Tao Nianlong Zou Ting Bao Xinghao Liang Zezhou Chen Shanghua Xu Ce Bian Zhiming Xu Chong Wang Chen Si Wenhui Duan Yong Xu 《Science Bulletin》 SCIE EI CAS 2024年第16期2514-2521,共8页
Realizing large materials models has emerged as a critical endeavor for materials research in the new era of artificial intelligence,but how to achieve this fantastic and challenging objective remains elusive.Here,we ... Realizing large materials models has emerged as a critical endeavor for materials research in the new era of artificial intelligence,but how to achieve this fantastic and challenging objective remains elusive.Here,we propose a feasible pathway to address this paramount pursuit by developing universal materials models of deep-learning density functional theory Hamiltonian(Deep H),enabling computational modeling of the complicated structure-property relationship of materials in general.By constructing a large materials database and substantially improving the Deep H method,we obtain a universal materials model of Deep H capable of handling diverse elemental compositions and material structures,achieving remarkable accuracy in predicting material properties.We further showcase a promising application of fine-tuning universal materials models for enhancing specific materials models.This work not only demonstrates the concept of Deep H's universal materials model but also lays the groundwork for developing large materials models,opening up significant opportunities for advancing artificial intelligencedriven materials discovery. 展开更多
关键词 Large materials model universal materials model Deep-learning density functional theory Artificial intelligence-driven materials discovery
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Scaling relation of domain competition on(2+1)-dimensional ballistic deposition model with surface diffusion
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作者 Kenyu Osada Hiroyasu Katsuno +1 位作者 Toshiharu Irisawa Yukio Saito 《Journal of Semiconductors》 EI CAS CSCD 2016年第9期12-17,共6页
During heteroepitaxial overlayer growth multiple crystal domains nucleated on a substrate surface compete with each other in such a manner that a domain covered by neighboring ones stops growing.The number density of ... During heteroepitaxial overlayer growth multiple crystal domains nucleated on a substrate surface compete with each other in such a manner that a domain covered by neighboring ones stops growing.The number density of active domains ρ decreases as the height h increases.A simple scaling argument leads to a scaling law of ρ~ h^(-γ) with a coarsening exponent γ=d/z,where d is the dimension of the substrate surface and z the dynamic exponent of a growth front.This scaling relation is confirmed by performing kinetic Monte Carlo simulations of the ballistic deposition model on a two-dimensional(d=2) surface,even when an isolated deposited particle diffuses on a crystal surface. 展开更多
关键词 domain competition ballistic deposition model Kardar-Parisi-Zhang universality class surface diffusion
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Neutrino masses,cosmological inflation and dark matter in a variant U(1)B-L model with type II seesaw mechanism
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作者 J.G.Rodrigues A.C.O.Santos +1 位作者 J.G.Ferreira Jr C.A.de S.Pires 《Chinese Physics C》 SCIE CAS CSCD 2021年第2期621-630,共10页
In this study,we implemented the type Ⅱ seesaw mechanism into the framework of the U(l)B-L gauge model.To achieve this,we added a scalar triplet,A,to the canonical particle content of the U(l)B-Lgauge model.By imposi... In this study,we implemented the type Ⅱ seesaw mechanism into the framework of the U(l)B-L gauge model.To achieve this,we added a scalar triplet,A,to the canonical particle content of the U(l)B-Lgauge model.By imposing that the U(l)B-L gauge symmetry be spontaneously broken at TeV scale,we show that the type Ⅱ seesaw mechanism is realized at an intermediate energy scale,more precisely,at approximately 109 GeV.To prevent heavy right-handed neutrinos from disturbing the mechanism,we evoke a Z2 discrete symmetry.Interestingly,as a result,we have standard neutrinos with mass around eV scale and right-handed neutrinos with mass in TeV scale,with the lightest one fulfilling the condition of dark matter.We developed all of these in this study.In addition,we show that the neutral component of Δ may perform unproblematic non-minimal inflation with loss of unitarity. 展开更多
关键词 models beyond the standard model particle-theory and field-theory models of the early universe neutrino mass and mixing
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Short Group Signatures Without Random Oracles 被引量:1
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作者 秦波 伍前红 +3 位作者 Willy Susilo 穆怡 王育民 姜正涛 《Journal of Computer Science & Technology》 SCIE EI CSCD 2007年第6期805-821,共17页
We propose short group signature (GS) schemes which are provably secure without random oracles. Our basic scheme is about 14 times shorter than the Boyen-Waters GS scheme at Eurocrypt 2006, and 42% shorter than the ... We propose short group signature (GS) schemes which are provably secure without random oracles. Our basic scheme is about 14 times shorter than the Boyen-Waters GS scheme at Eurocrypt 2006, and 42% shorter than the recent GS schemes due to Ateniese et al. The security proofs are provided in the Universally Composable model, which allows the proofs of security valid not only when our scheme is executed in isolation, but also in composition with other secure cryptographic primitives. We also present several new computational assumptions and justify them in the generic group model. These assumptions are useful in the design of high-level protocols and may be of independent interest. 展开更多
关键词 group signature information security standard model universally composable model
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Towards a Framework for Evaluating the Research Performance of Chinese Double First-Class Universities 被引量:1
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作者 XU Changqing 《Frontiers of Education in China》 2020年第3期369-402,共34页
The study focuses on the research performance of Double First-Class(DFC)universities in China.A theoretical framework based on economic theory and the Analytic Hierarchy Process(AHP)method for a novel evaluation model... The study focuses on the research performance of Double First-Class(DFC)universities in China.A theoretical framework based on economic theory and the Analytic Hierarchy Process(AHP)method for a novel evaluation model is proposed.The model is performed on a sample of 41 participant DFC universities in China.Using data collected from these universities,it was found that there is no consistency between performance ranking,input ranking,and output ranking,with the best ranked universities far from the most efficient.These findings provide empirical evidence of DFC universities’research performance situation and suggest strategies that the government can use to propel their sustainable development. 展开更多
关键词 Double First-Class(DFC)university research performance Double First-Class University Research Performance Evaluation model(DFCuRPE model) evaluation validation
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