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New Topologies of High Torque Density Machine Based on Magnetic Field Modulation Principle 被引量:1
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作者 Yan Yue Shaofeng Jia Deliang Liang 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第1期1-10,共10页
With the increasing demand for high torque density in motors,more and more new topologies emerge.Furthermore,the magnetic field modulation principle is widely concerned and has evolved into an effective analysis metho... With the increasing demand for high torque density in motors,more and more new topologies emerge.Furthermore,the magnetic field modulation principle is widely concerned and has evolved into an effective analysis method for studying the new motor topology.This paper introduces the principle of magnetic field modulation.And the research on high torque density in recent years is reviewed from the perspective of magnetic field modulation,including permanent magnet vernier machine(PMVM),flux reverse machine(FRM),flux switching machine(FSM),dual permanent magnet(DPM)machine,and DC biased machine.The principle of magnetic field modulation makes it possible to propose higher torque density topologies in the future. 展开更多
关键词 index Terms-High torque density Magnetic field modulation Vernier machine Dual permanent magnet machine DC biased machine
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Effects of different land-use systems (grazing and understory cultivation) on growth and yield of semi-arid oak coppices 被引量:2
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作者 Ali Soltani Hamdollah Sadeghi Kaji Saleh Kahyani 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第6期2235-2244,共10页
The present study examines the extent of negative eff ects of traditional multiple land-use systems on oak coppices,from a forest management point of view.The study area was located in approximately 10,000 ha of hilly... The present study examines the extent of negative eff ects of traditional multiple land-use systems on oak coppices,from a forest management point of view.The study area was located in approximately 10,000 ha of hilly Brant’s oak(Quercus brantii Lindl.)woodlands in the central Zagros Mountains.In the same site-quality class,three land-use systems were compared:simple coppice(Co),coppice in conjunction with small ruminant grazing(CoG),and coppice with understory rain-fed wheat cultivation plus grazing(CoCG).Data on total wood volume of trunk and major branches,and annual ring growth,were collected and analyzed from 74 stands in 15 coppiced woodland patches.The results showed the advantage of Co over CoG and CoCG land-uses by 43 and 60 m 3 of mean accumulated wood volume per hectare,respectively.The diameter growth analysis also revealed an annual increase in wood production of trees in Co land-uses over 43 years,with an exception of the recent decade,when growth coincided with a severe drought.Using a back-extrapolation method,the minimum rotation age of woodlands in Co land-use was found to be 23.6 years,5 and 7 years shorter than those of CoG and CoCG land-uses,respectively.Unlike CoCG,woodlands located in Co and CoG land-use systems demonstrated a high level of agreement with self-thinning rule of−3/2.Values for the stand density index for coppiced oak woodlands were between more than 1000 for the least disturbed(Co)and less than 400 for the most disturbed woodlands(CoCG).The structure and growth rate of the coppiced oak woodlands were irreversibly disrupted by understory tillage plus grazing and in less extent by grazing alone.It was concluded that ending undergrowth cultivation in semi-arid oak coppices should be addressed as a priority by adopting minimum regulations. 展开更多
关键词 COPPICING Land-use impact assessment Diameter growth Multi-purpose land-use Self-thinning rule Stand density index
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Analysis Neotectonic Activities in Khafr Basin
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作者 Ahmad Ansari Lari Maryam Ansari Soraya Ansari 《Open Journal of Geology》 2016年第6期484-497,共14页
As Iran is located on one of the two earthquake-prone belts in the world, and existence of faults and earthquakes is normal in Iran tableland. The main reason of earthquake is Neotectonic movements which can be effect... As Iran is located on one of the two earthquake-prone belts in the world, and existence of faults and earthquakes is normal in Iran tableland. The main reason of earthquake is Neotectonic movements which can be effective in other natural disasters such as range movements. Due to the severe shortage of historical and seismic data and device in different parts of the world, particularly Iran, need for introducing more researchers and planners of Iran to tectonics and active tectonic areas is more visible. This study is an investigation of Neotectonic activities in Khafr basin area, Fars province. To achieve the aims of this study morphometric parameters were used. Investigations showed that severity and role of tectonic activities in different parts of the basin is different, results of geomorphic and tectonic assessments indicate these differences.Stream length-gradient index (SL) on the main stream is inactive and sub streams are semi active, the ratio of the basin (BS) is 2.27, drainage basin asymmetry index (AF) is in semi active class, the ratio of width to depth of Valley (VF) shows 0.78. Indicators mentioned are in class 3 based on Iat classification, that represents tectonic activity in the area is average. Other indicators are indicative of active tectonic in the basin such as drainage density index (D) with high density, river sinuosity (S) 1.25, reverse topography symmetry Factor (T) 0.3.Generally it can be considered as moderately active region in terms of tectonic activities. 展开更多
关键词 NEOTECTONIC Geomorphic Indicators Drainage density index Basin of Khafr
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Determination of physical properties for the mixtures of [BMIM]Cl with different organic solvents 被引量:2
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作者 Hina Saba Xinjun Zhu +1 位作者 Ye Chen Yumei Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第5期804-811,共8页
Physical properties including refractive index, density, viscosity and conductivity for binary mixtures of l-butyl- 3-methyl imidazolium chloride ([BMIM]CI) and different organic solvents at 298.15 K have been inves... Physical properties including refractive index, density, viscosity and conductivity for binary mixtures of l-butyl- 3-methyl imidazolium chloride ([BMIM]CI) and different organic solvents at 298.15 K have been investigated. Ex- cess molar volumes have been calculated and obtained data has been fitted by the Redlich-Kister equation. The density and refractive index were found to increase with increasing concentration of [BMIM]CI, however, excep- tions do exist as in the case of dimethyl sulfoxide (DMSO)/[BMIM]CI. For DMSO/[BMIM]CI, the density decreases with increasing concentration. The addition of different organic solvents was able to disrupt the interactions within mixtures, leading to free mobility of ions. The free mobility of ions has been found to enhance conductivity and decrease viscosity to varying extents in all mixtures studied. It has been observed that solubility parameters, dielectric constants and composition of the solvents used play a vital role in determining the resultant properties. The data obtained will play an important role in understanding the effect of the addition of organic solvents in ILs to enhance their applicability. 展开更多
关键词 Ionic liquid Viscosity Conductivity Refractive index density Binary mixtures Organic solvents
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Excited state refraction of C_(70)/toluene studied by using 4f coherent imaging system with phase object 被引量:1
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作者 刘南春 石光 +1 位作者 杨俊义 宋瑛林 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期304-309,共6页
Dynamic nonlinearities of C70/toluene solution are measured and analysed by an improved picosecond timeresolved pump-probe system based on a nonlinear imaging technique with phase object. The photophysical parameters ... Dynamic nonlinearities of C70/toluene solution are measured and analysed by an improved picosecond timeresolved pump-probe system based on a nonlinear imaging technique with phase object. The photophysical parameters are determined by the five-level model, which is adopted to interpret the experimental data. The change of refraction index per unit density of the excited state obtained by a numerically simulation is a critical factor to determine the nonlinear behaviour of C70 in picosecond time regime. 展开更多
关键词 4f system excited state refraction C70/toluene solution refraction index per unit density
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No evidence for the evolution of mass density power-law index γ from strong gravitational lensing observation
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作者 Jing-Lei Cui Hai-Li Li Xin Zhang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2017年第8期8-14,共7页
In this paper, we consider the singular isothermal sphere lensing model that has a spherically symmetric power-law mass dis- tribution ρtot(r) - r-γ. We investigate whether the mass density power-law index y is co... In this paper, we consider the singular isothermal sphere lensing model that has a spherically symmetric power-law mass dis- tribution ρtot(r) - r-γ. We investigate whether the mass density power-law index y is cosmologically evolutionary by using the strong gravitational lensing (SGL) observation, in combination with other cosmological observations. We also check whether the constraint result of y is affected by the cosmological model, by considering several simple dynamical dark energy models. We find that the constraint on y is mainly decided by the SGL observation and independent of the cosmological model, and we find no evidence for the evolution of y from the SGL observation. 展开更多
关键词 strong gravitational lensing mass density power-law index dynamical dark energy cosmological parameter estimation
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Physicochemical properties of aqueous solutions of sodium glycinate in the non-precipitation regime from 298.15 to 343.15 K
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作者 Muhammad Shuaib Shaikh Azmi Mohd Shariff +1 位作者 Mohd Azmi Bustam Ghulam Murshid 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第3期536-540,共5页
The physicochemical properties,including the density,viscosity,and refractive index of aqueous solutions of sodium glycinate as a solvent for CO_2 absorption in the non-precipitation regime were measured under the wid... The physicochemical properties,including the density,viscosity,and refractive index of aqueous solutions of sodium glycinate as a solvent for CO_2 absorption in the non-precipitation regime were measured under the wide temperature range of 298.15 to 343.15 K.The concentration of the sodium glycinate in an aqueous form in the non-precipitation regime was identified up to 2.0 mol ? L^(-1).The coefficients of thermal expansion values were estimated from measured density data.It was found that,the densities,viscosities and refractive indices of the aqueous sodium glycinate decrease with an increase in temperature,whereas with increasing sodium glycinate concentration in the solution,all three properties increase.Thermal expansion coefficients slightly increase with rising temperature and concentration.The measured values of density,viscosity and refractive index were correlated as a function of temperature by using the least squares method.The predicted data obtained from correlation equations for all measured properties were in fairly good agreement with the experimental data. 展开更多
关键词 Sodium glycinate Physicochemical property density Viscosity Refractive index
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An Effective Density Based Approach to Detect Complex Data Clusters Using Notion of Neighborhood Difference 被引量:4
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作者 S. Nagaraju Manish Kashyap Mahua Bhattachraya 《International Journal of Automation and computing》 EI CSCD 2017年第1期57-67,共11页
The density based notion for clustering approach is used widely due to its easy implementation and ability to detect arbitrary shaped clusters in the presence of noisy data points without requiring prior knowledge of ... The density based notion for clustering approach is used widely due to its easy implementation and ability to detect arbitrary shaped clusters in the presence of noisy data points without requiring prior knowledge of the number of clusters to be identified. Density-based spatial clustering of applications with noise (DBSCAN) is the first algorithm proposed in the literature that uses density based notion for cluster detection. Since most of the real data set, today contains feature space of adjacent nested clusters, clearly DBSCAN is not suitable to detect variable adjacent density clusters due to the use of global density parameter neighborhood radius Y,.ad and minimum number of points in neighborhood Np~,. So the efficiency of DBSCAN depends on these initial parameter settings, for DBSCAN to work properly, the neighborhood radius must be less than the distance between two clusters otherwise algorithm merges two clusters and detects them as a single cluster. Through this paper: 1) We have proposed improved version of DBSCAN algorithm to detect clusters of varying density adjacent clusters by using the concept of neighborhood difference and using the notion of density based approach without introducing much additional computational complexity to original DBSCAN algorithm. 2) We validated our experimental results using one of our authors recently proposed space density indexing (SDI) internal cluster measure to demonstrate the quality of proposed clustering method. Also our experimental results suggested that proposed method is effective in detecting variable density adjacent nested clusters. 展开更多
关键词 density based clustering neighborhood difference density-based spatial clustering of applications with noise (DBSCAN) space density indexing (SDI) core object.
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Atmospheric environmental capacity and urban atmospheric load in China's Mainland 被引量:8
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作者 XU DaHai WANG Yu ZHU Rong 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第1期33-46,共14页
Daily and annual average atmospheric environmental capacity coefficient(A-value) sequences for China's Mainland are calculated from hourly data recorded at 378 ground stations over 1975–2014. A-values at differen... Daily and annual average atmospheric environmental capacity coefficient(A-value) sequences for China's Mainland are calculated from hourly data recorded at 378 ground stations over 1975–2014. A-values at different recurrence intervals are calculated by fitting the sequences to Pearson type III distribution curves. Based on these A-values and source-sink balance(reference concentration 100 μg m^(-3)), atmospheric environmental capacities at the recurrence intervals are calculated for all of China's Mainland and each provincial administrative region. The climate average atmospheric environmental capacity reference value for the entire mainland is 2.169×10~7 t yr^(-1). An urban atmospheric load index is defined for analyses of the impact of population density on the urban atmospheric environment. Analyses suggest that this index is also useful for differentiating whether air quality changes are attributable to varying meteorological conditions or variations of artificial emission rate.Equations guiding the control of unorganized emission sources are derived for preventing air quality deterioration during urban expansion and population concentration. 展开更多
关键词 Atmospheric environmental capacity Pearson type III distribution Recurrence interval Urban atmospheric load index Emission rate density
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