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Estimation of fracture size and azimuth in the universal elliptical disc model based on trace information 被引量:3
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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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A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in aqueous solutions and its applications in binary and ternary aqueous solutions 被引量:1
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作者 杨学民 赵伟洁 +2 位作者 柴国明 郭汉杰 张强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期626-641,共16页
A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexi... A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexistence theory and verified in four kinds of binary aqueous solutions and two kinds of ternary aqueous solutions. The calculated mass action concentrations of structural units or ion couples in four binary aqueous solutions and two ternary solutions at 298.15 K have good agreement with the reported activity data from literatures after shifting the standard state and concentration unit. Therefore, the calculated mass action concentrations of structural units or ion couples from the developed universal thermodynamic model for ternary and binary aqueous solutions can be applied to predict reaction ability of components in ternary and binary strong electrolyte aqueous solutions. It is also proved that the assumptions applied in the developed thermodynamic model are correct and reasonable, i.e., strong electrolyte aqueous solution is composed of cations and anions as simple ions, H2O as simple molecule and other hydrous salt compounds as complex molecules. The calculated mass action concentrations of structural units or ion couples in ternary and binary strong electrolyte aqueous solutions strictly follow the mass action law. 展开更多
关键词 universal thermodynamic model mass action concentration activity ternary aqueous solution binary aqueous solution ion and molecule coexistence theory structural units ion couples components
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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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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 CSCD 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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Comparative study and error analysis of digital elevation model interpolations 被引量:1
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作者 陈吉龙 《Journal of Chongqing University》 CAS 2008年第4期277-283,共7页
Researchers in P.R.China commonly create triangulate irregular networks(TINs) from contours and then convert TINs into digital elevation models(DEMs).However,the DEM produced by this method can not precisely describe ... Researchers in P.R.China commonly create triangulate irregular networks(TINs) from contours and then convert TINs into digital elevation models(DEMs).However,the DEM produced by this method can not precisely describe and simulate key hydrological features such as rivers and drainage borders.Taking a hilly region in southwestern China as a research area and using ArcGISTM software,we analyzed the errors of different interpolations to obtain distributions of the errors and precisions of different algorithms and to provide references for DEM productions.The results show that different interpolation errors satisfy normal distributions,and large error exists near the structure line of the terrain.Furthermore,the results also show that the precision of a DEM interpolated with the Australian National University digital elevation model(ANUDEM) is higher than that interpolated with TIN.The DEM interpolated with TIN is acceptable for generating DEMs in the hilly region of southwestern China. 展开更多
关键词 digital elevation model (DEM) INTERPOLATION triangulate irregular network (TIN) Australian National University digital elevation model (ANUDEM)
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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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A new strategy to iteratively update scalable universal quantitative models for the testing of azithromycin by near infrared spectroscopy 被引量:5
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作者 ZOU WenBo FENG YanChun +2 位作者 DONG JiXiong SONG DanQing HU ChangQin 《Science China Chemistry》 SCIE EI CAS 2013年第4期533-540,共8页
The training set of a universal near infrared (NIR) model for quantitative analysis of a drug should cover as many samples of this drug in the market as possible. Inevitably the model may fail for new products that ha... The training set of a universal near infrared (NIR) model for quantitative analysis of a drug should cover as many samples of this drug in the market as possible. Inevitably the model may fail for new products that have different excipients and production processes. In such circumstances the model should be updated. We here propose a new strategy to iteratively update a universal NIR quantitative model for azithromycin. We prove that universal quantitative models generated from this new strategy are comparably effective for azithromycin injection powders and azithromycin tablets, compared to the strategy using hierarchical clustering method which we reported previously. Furthermore, we establish the correlation coefficient r between a new sample and the training set samples can be used to decide whether or not the model should be updated. 展开更多
关键词 near infrared spectroscopy universal quantitative model model updating AZITHROMYCIN
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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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Construction of universal calibration model for levofloxacin injections by fiber-optic transmittance-reflectance near-infrared spectroscopy
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作者 Shao-Rui Hou Yan-Chun Feng +1 位作者 Xue-Bo Zhang Chang-Qin Hu 《Journal of Chinese Pharmaceutical Sciences》 CAS 2012年第1期62-69,共8页
The general strategy and method of constructing universal calibration model for levofioxacin injections by near-infrared spectroscopy have been investigated and discussed. Firstly, a constant-temperature homogeneous l... The general strategy and method of constructing universal calibration model for levofioxacin injections by near-infrared spectroscopy have been investigated and discussed. Firstly, a constant-temperature homogeneous liquid calibration model for levofloxacin hydrochloride injections with the same composition but different active principal ingredient (API) content was established as the basic unit for universal model. Then, samples of levofloxacin hydrochloride injections containing propylene glycol or levofloxacin lactate injections were added to develop a primary constant-temperature liquid universal model. Temperature- amended final universal model was established to apply to samples under different temperatures. The final model was built from 61 calibration samples and 77 validation samples. The value of the root mean square error of cross validation (RMSECV) and coefficient of determination (r2) of leave-one-out cross-validation (LOOCV) were 0.792 and 0.9993, respectively, the root mean square error of prediction (RMSEP) of test set validation (TSV) was 0.87, and the average relative deviation was 1.44%. According to the ICH guidelines, the universal calibration model was evaluated. Based on the experimental statistical results, the recommended number of calibration samples for a constant-temperature homogeneous liquid quantitative model was no less than 15. 展开更多
关键词 Near-infrared spectroscopy Liquid universal calibration model Levofloxacin injection Sampling by fiber-optic transmittance-reflectance mode
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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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Approach to lattice-related/content-specific spectral ranges of near-infrared diffuse reflectance spectroscopy of cefazolin sodium and the construction of a quantitative model for the determination of cefazolin sodium content in different crystal forms 被引量:3
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作者 LIU YanYun FENG YanChun +1 位作者 JIA YanHua HU ChangQin 《Science China Chemistry》 SCIE EI CAS 2013年第6期789-798,共10页
Cefazolin sodium can form both α- and β-form crystals. It also can form dehydrated crystalline and amorphous products through different production processes. Because different polymorphic medicines usually have diff... Cefazolin sodium can form both α- and β-form crystals. It also can form dehydrated crystalline and amorphous products through different production processes. Because different polymorphic medicines usually have different physical and chemical properties, it is critical to emphasize the crystallization control of polymorphic medicines. Near-infrared (NIR) analysis, which incorporates a combination of NIR spectroscopic techniques and multivariate chemometric methods, is considered a powerful tool for the determination of the crystallinity of polymorphic drugs. The selection of optimal spectral ranges that correlate with the lattice specificity and content specificity is crucial to obtaining a specific NIR model. In the present work, near-infrared (NIR) spectra of cefazolin sodium with different crystal forms created through different processes were studied. The results suggest that wavelengths within the range of 9102.7-8597.5 cm-1 is related to the specificity of the cefazolin sodium crystal lattice and that the range of 6001.6-5496.4 cm i is associated with the quantitative content of cefazolin sodium. The two ab- sorptions are caused by the second overtone of the C-H stretching band (3nC-H) and the first overtone of C-H stretching band (2uC-H), respectively. Using these results, we established a suitable method of constructing a universal quantitative model by using mixed samples in different crystal forms as a calibration set, selecting a content-specific range (6001.6-5496.4 cm-l), and adding lattice-related spectral ranges where appropriate. This may provide a framework for the construction of prediction models for polymorphic medicines. 展开更多
关键词 cefazolin sodium crystal form near-infrared spectroscopy crystal-specific model universal model
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