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A Linear Combination of Superderivations on Prime Superalgebras 被引量:1
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作者 袁鹤 《Northeastern Mathematical Journal》 CSCD 2008年第5期399-408,共10页
In the paper, we give some results about a linear combination of superderivations on prime superalgebras and generalize a result of Niu Feng-wen.
关键词 prime superalgebra SUPERDERIVATION linear combination
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Quantitative analysis of glutamate compounds in the swine brain following central analgesics nasal spray using proton magnetic resonance spectroscopy and linear combination model
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作者 Jianlin Wu Ting Liu +4 位作者 Yan Lin Zhiwei Shen Yanwei Miao Renhua Wu Changkai Sun 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第7期508-512,共5页
BACKGROUND: In localized brain proton magnetic resonance spectroscopy (^1H-MRS), metabolite levels are often expressed as ratios, rather than absolute concentrations. Frequently, the denominator is creatine, which ... BACKGROUND: In localized brain proton magnetic resonance spectroscopy (^1H-MRS), metabolite levels are often expressed as ratios, rather than absolute concentrations. Frequently, the denominator is creatine, which is assumed to be stable in normal, as well as many pathological, states. However, in vivo creatine levels do not remain constant. Therefore, absolute metabolite measurements, which provide the precise concentrations of certain chemical compounds, are superior to metabolite ratios for determining pathological and evolutional changes. OBJECTIVE: To investigate the feasibility of quantification analysis of brain metabolite changes caused by central analgesics nasal spray using the ^1H-MRS and linear combination model (LCModel) methods. DESIGN, TIME AND SETTING: This neuroimaging, observational, animal study was performed at the Laboratory of the Department of Medical Imaging, Second Affiliated Hospital, Medical College, Shantou University, China from July to December 2007. MATERIALS: Butorphanol tartrate nasal spray, as a mixed agonist-antagonist opioid analgesic, was purchased from Shanghai Hengrui Pharmacy, China. A General Electric Signa 1.5T System (General Electric Medical Systems, Milwaukee, WI, USA) and LCModel software (Stephen Provencher, Oakville, Ontario, Canada) were used in this study. METHODS: MRS images were acquired in ten healthy swine aged 2 weeks using single-voxel point-resolved spectroscopic sequence. A region of interest (2 cm × 2 cm × 2 cm) was placed in the image centers of maximum brain parenchyma. Repeated MRS scanning was performed 15-20 minutes after intranasal administration of 1 mg of butorphanol tartrate. Three settings of repetition time/echo time were selected before and after nasal spray administration 3 000 ms/30 ms,1 500 ms/30 ms, and 3 000 ms/50 ms. Metabolite concentrations were estimated by LCModel software. MAIN OUTCOME MEASURES: ^1H-MRS spectra was obtained using various repetition time/echo time settings. Concentrations of glutamate compounds (glutamate + glutamine), N-acetyl aspartate, and choline were detected in swine brain prior to and following nasal spray treatment. RESULTS: The glutamate compounds curve was consistent with original spectra, when a repetition time/echo time of 3 000 ms/30 ms was adopted. Concentrations of glutamate compounds, N-acetyl aspartate, and choline decreased following administration. The most significant reduction was observed in glutamate compound concentrations from (9.28 ± 0.54) mmol/kg to (7.28 ± 0.54) mmol/kg (P 〈 0.05). CONCLUSION: ^1H-MRS and LCModel software were effectively utilized to quantitatively analyze and measure brain metabolites. Glutamate compounds might be an important neurotransmitter in central analgesia. 展开更多
关键词 proton magnetic resonance spectroscopy nasal spray linear combination model glutamate compounds absolute quantification
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Determination of Light Rare Earths by a Spectrophoto-metry Based on the Linear Combination of Multiwavelength Data
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作者 刘思东 崔秀君 +1 位作者 郭伊荇 李永涛 《Journal of Rare Earths》 SCIE EI CAS CSCD 1993年第3期211-215,共5页
The present paper proposes a new method of spectrophotometry based on linear combination of multiwavelength data by means of selecting a set of properly weighted coefficients and combination methods. It is clear that ... The present paper proposes a new method of spectrophotometry based on linear combination of multiwavelength data by means of selecting a set of properly weighted coefficients and combination methods. It is clear that the weighted combination absorbance attained is only in direct proportion to the concentration of the analysed component and independent of coexisting interferents.The accuracy of the analytical results is improved greatly for the analysis of light rare earths with the coexistence of heavy rare earths.The analyti- cal error from the reagent blank and co-coloration of light and heavy rare earths have also been overcome. The greatly improved linearity and additivity of absorbance are obtained. 展开更多
关键词 linear combination of multiwavelength data Computational spectrophotometry CPAⅢ Determination of light rare earths
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Firey linear combinations of convex bodies
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作者 熊革 肖启名 CHEUNG Wing-Sum 《Journal of Shanghai University(English Edition)》 CAS 2009年第2期102-104,共3页
For convex bodies, the Firey linear combinations were introduced and studied in several papers. In this paper the mean width of the Firey linear combinations of convex bodies is studied, and the lower bound of the mea... For convex bodies, the Firey linear combinations were introduced and studied in several papers. In this paper the mean width of the Firey linear combinations of convex bodies is studied, and the lower bound of the mean width of the Firey linear combinations of convex body and its polar body is given. 展开更多
关键词 convex body Firey linear combination mean width
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EXPLICIT VORONOVSKAJA-TYPE RESULTS FOR LINEAR COMBINATIONS OF BDT-OPERATORS
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作者 M. Heilmann 《Analysis in Theory and Applications》 1995年第1期54-61,共8页
In this paper me prove an explicit Vcionovskvja-type result for linear combmations of the so-called BDT -operators.
关键词 EXPLICIT VORONOVSKAJA-TYPE RESULTS FOR linear combinationS OF BDT-OPERATORS
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BDS triple-frequency carrier-phase linear combination models and their characteristics 被引量:18
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作者 ZHANG XiaoHong HE XiYang 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第6期896-905,共10页
An investigation has been made on the models and characteristics of triple-frequency carrier-phase linear combinations for the Bei Dou Navigation Satellite System(BDS). Based on the three frequencies of the BDS, three... An investigation has been made on the models and characteristics of triple-frequency carrier-phase linear combinations for the Bei Dou Navigation Satellite System(BDS). Based on the three frequencies of the BDS, three categories of combinations are developed: ionosphere-free combinations(i.e., those that eliminate the ionospheric effect), minimum-noise combinations(those that mitigate the effects of thermal noise and multiple paths), and troposphere-free combinations(those that mitigate tropospheric effects). Both the ionosphere-free and troposphere-free combinations can be expressed as planes, whereas the minimum-noise combinations can be expressed as a line. The relationships between these three categories of linear combinations are investigated from the perspective of geometry. The angle between the troposphere-free plane and ionosphere-free plane is small, while the angles between the troposphere-free plane and the minimum-noise line, and between the ionosphere-free plane and the minimum-noise line, are large. Specifically, the troposphere-free plane is orthogonal to the minimum-noise line. By introducing the concepts of lane number and integer ionosphere number, the characteristics of the long-wavelength integer combinations and ionosphere-free integer combinations are investigated. The analysis indicates that the longest wavelength that can be formed for integer combinations is 146.53 m, and the ionosphere-free integer combinations all have large noise amplification factors. The ionosphere-free integer combination with minimum noise amplification factor is(0, 62, 59). According to the lane number, integer ionosphere number, and noise amplification factor, optimal integer combinations with different characteristics are presented. For general short baselines and long baselines, three independent integer combinations are suggested. 展开更多
关键词 BeiDou Navigation Satellite System triple-frequency linear combination long wavelength ionosphere-free minimum noise
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Linear Combinations of Composition Operators on Weighted Dirichlet Spaces 被引量:1
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作者 CHEN Peng 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2015年第5期369-374,共6页
In this paper, linear combinations of composition operators acting on weighted Dirichlet spaces are studied. By using the first derivative of the kernel function, we obtain a lower estimate for the essential norms of ... In this paper, linear combinations of composition operators acting on weighted Dirichlet spaces are studied. By using the first derivative of the kernel function, we obtain a lower estimate for the essential norms of these operators acting on the Dirichlet space D and S2. For general weighted Dirichlet space, by using complex interpolation methods, we characterize the compactness of these operators induced by linear fractional self-maps of the disk. 展开更多
关键词 linear combinations of composition operator compact operator weighted Dirichlet spaces complex interpolation
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Combinations of Right Half-Plane Mappings and Vertical Strip Mappings Convex in the Vertical Direction
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作者 Yulin Cai Zirun She +1 位作者 Fanji Zeng Lu Huang 《Open Journal of Statistics》 2023年第6期941-954,共14页
In this paper, we explore the linear combinations of right half-plane mappings and vertical strip mappings. We demonstrate that the combinations of these harmonic mappings are convex in the vertical direction provided... In this paper, we explore the linear combinations of right half-plane mappings and vertical strip mappings. We demonstrate that the combinations of these harmonic mappings are convex in the vertical direction provided they are locally univalent and sense-preserving. Furthermore, we extend this analysis to a more general case by setting specific conditions. Additionally, we take some common parameters such as  as the dilatation of these harmonic mappings, and prove the sufficient conditions that their combinations are locally univalent and convex in the vertical direction. Several examples are constructed by the Mathematica software to demonstrate our main results. 展开更多
关键词 Harmonic Mapping linear combination Cohn’s Rules Directional Convexi-ty
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Revisiting ENSO impacts on the Indian Ocean SST based on a combined linear regression method 被引量:1
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作者 Lianyi Zhang Yan Du +1 位作者 Tomoki Tozuka Shoichiro Kido 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第5期47-57,共11页
The El Nino-Southern Oscillation(ENSO)has great impacts on the Indian Ocean sea surface temperature(SST).In fact,two major modes of the Indian Ocean SST namely the Indian Ocean Basin(IOB)and the Indian Ocean Dipole(IO... The El Nino-Southern Oscillation(ENSO)has great impacts on the Indian Ocean sea surface temperature(SST).In fact,two major modes of the Indian Ocean SST namely the Indian Ocean Basin(IOB)and the Indian Ocean Dipole(IOD)modes,exerting strong influences on the Indian Ocean rim countries,are both influenced by the ENSO.Based on a combined linear regression method,this study quantifies the ENSO impacts on the IOB and the IOD during ENSO concurrent,developing,and decaying stages.After removing the ENSO impacts,the spring peak of the IOB disappears along with significant decrease in number of events,while the number of events is only slightly reduced and the autumn peak remains for the IOD.By isolating the ENSO impacts during each stage,this study reveals that the leading impacts of ENSO contribute to the IOD development,while the delayed impacts facilitate the IOD phase switch and prompt the IOB development.Besides,the decadal variations of ENSO impacts are various during each stage and over different regions.These imply that merely removing the concurrent ENSO impacts would not be sufficient to investigate intrinsic climate variability of the Indian Ocean,and the present method may be useful to study climate variabilities independent of ENSO. 展开更多
关键词 Indian Ocean ENSO sea surface temperature climate modes combined linear regression
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Generation of Linear Isolated Sub-60 Attosecond Pulses by Combining a Circularly Polarized Pulse with an Elliptically Polarized Pulse 被引量:1
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作者 夏昌龙 苗向阳 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第4期38-41,共4页
The two-color circularly polarized pulses scheme was proposed to generate isolated attosecond pulses in our previous work [Phys. Rev. A 87 (2013) 043406], while the polarization of the attosecond pulse was not inves... The two-color circularly polarized pulses scheme was proposed to generate isolated attosecond pulses in our previous work [Phys. Rev. A 87 (2013) 043406], while the polarization of the attosecond pulse was not investigated. We show a supplementary explanation of this scheme and present another scheme to generate linear isolated attosecond pulses by combining a circularly polarized pulse with an elliptically polarized pulse. High-order harmonic generation and quantum path control are investigated to compare these two schemes. Both schemes can obtain supercontinuum spectra plateau from about 200eV to 550eV, which belong to the water window region. It is found that the latter scheme can clearly eliminate the short quantum path and extend the harmonic plateau. A linear isolated attosecond pulse with a duration of sub-6Oas can be generated by superposing a bandwidth of 70eV. 展开更多
关键词 Generation of linear Isolated Sub-60 Attosecond Pulses by Combining a Circularly Polarized Pulse with an Elliptically Polarized Pulse
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Bound Polaron in a Quantum Well Under an Electric Field 被引量:4
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作者 陈伟丽 肖景林 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第5期787-791,共5页
We conduct a theoretical study on the properties of a bound polaron in a quantum well under an electric field using linear combination operator and unitary transformation methods, which are valid in the whole range of... We conduct a theoretical study on the properties of a bound polaron in a quantum well under an electric field using linear combination operator and unitary transformation methods, which are valid in the whole range of electron-LO phonon coupling. The changing relations between the ground-state energy of the bound polaron in the quantum well and the Coulomb bound potential, the electric field strength, and the well width are derived. The numerical results show that the ground-state energy increases with the increase of the electric field strength and the Coulomb bound potential and decreases as the well width increases. 展开更多
关键词 quantum well bound polaron ground-state energy linear combination operator electric field
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Influence of the Electric Field on the Properties of the Bound Magnetopolaron in GaAs Semiconductor Quantum Wells 被引量:3
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作者 单淑萍 肖景林 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第3期438-441,共4页
The influence of the electric field on the properties of the bound magnetopolaron in an infinite-depth GaAs semiconductor quantum well is investigated using the linear-combination operator and the unitary transformati... The influence of the electric field on the properties of the bound magnetopolaron in an infinite-depth GaAs semiconductor quantum well is investigated using the linear-combination operator and the unitary transformation method. The relationships between the polaron's ground state energy and the Coulomb bound potential, electric field, magnetic field, and well-width are derived and discussed. Our numerical results show that the absolute value of the polaron's ground state energy increases as the electric field and the Coulomb bound potential increase, and decreases as the well-width and the magnetic field strength increase. When the well-width is small,the quantum size effect is significant. 展开更多
关键词 quantum well bound magnetopolaron linear combination operator ground state energy
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Kinematic Calibration and Forecast Error Compensation of a 2-DOF Planar Parallel Manipulator 被引量:5
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作者 CHANG Peng LI Chengrong LI Tiemin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第6期992-998,共7页
Due to large workspace,heavy-duty and over-constrained mechanism,a small deformation is caused and the precision of the 2-DOF planar parallel manipulator is affected.The kinematic calibration cannot compensate the end... Due to large workspace,heavy-duty and over-constrained mechanism,a small deformation is caused and the precision of the 2-DOF planar parallel manipulator is affected.The kinematic calibration cannot compensate the end-effector errors caused by the small deformation.This paper presents a method combined step kinematic calibration and linear forecast real-time error compensation in order to enhance the precision of a two degree-of-freedom(DOF) planar parallel manipulator of a hybrid machine tool.In the step kinematic calibration phase of the method,the end-effector errors caused by the errors of major constant geometrical parameters is compensated.The step kinematic calibration is based on the minimal linear combinations(MLCs) of the error parameters.All simple and feasible measurements in practice are given,and identification analysis of the set of the MLCs for each measurement is carried out.According to identification analysis results,both measurement costs and observability are considered,and a step calibration including step measurement,step identification and step error compensation is determined.The linear forecast real-time error compensation is used to compensate the end-effector errors caused by other parameters after the step kinematic calibration.Taking the advantages of the step kinematic calibration and the linear forecast real-time error compensation,a method for improving the precision of the 2-DOF planar parallel manipulator is developed.Experiment results show that the proposed method is robust and effective,so that the position errors are kept to the same order of the measurement noise.The presented method is attractive for the 2-DOF planar parallel manipulator and can be also applied to other parallel manipulators with fewer than six DOFs. 展开更多
关键词 parallel manipulator kinematic calibration error compensation minimal linear combinations (MLCs)
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Landslides susceptibility mapping in Guizhou province based on fuzzy theory 被引量:8
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作者 WANG Wei-dong XIE Cui-ming DU Xiang-gang 《Mining Science and Technology》 EI CAS 2009年第3期399-404,共6页
The purpose of this study was to assess the susceptibility of landslides around the area of Guizhou province based on fuzzy theory.In first instance, slope, elevation, lithology, proximity to tectonic lines, proximity... The purpose of this study was to assess the susceptibility of landslides around the area of Guizhou province based on fuzzy theory.In first instance, slope, elevation, lithology, proximity to tectonic lines, proximity to drainage and annual precipitation were taken as independent, causal factors in this study.A landslide hazard evaluation factor system was established by classifying these factors into more subclasses according to some rules.Secondly, a trapezoidal fuzzy number weighting(TFNW) approach was used to assess the importance of six causal factors to landslides in an ArcGIS environment.Thirdly, a landslide susceptibility map was created based on a weighted linear combination model.According to this susceptibility map, the study area was classified into four categories of landslide susceptibility:low, moderate, high and very high.Finally, in order to verify the results obtained, the susceptibility map and the landslide inventory map were combined in the GIS.In addition, the weighting procedure showed that TFNW is an efficient method for weighting causal landslide factors. 展开更多
关键词 landslides susceptibility mapping fuzzy theory GIS weighted linear combination
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THE DUAL BRUNN-MINKOWSKI INEQUALITIES FOR STAR DUAL OF MIXED INTERSECTION BODIES 被引量:2
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作者 朱先阳 沈亚军 《Acta Mathematica Scientia》 SCIE CSCD 2010年第3期739-746,共8页
In this article, some dual Brunn-Minkowski inequalities are established for star dual of mixed intersection bodies with respect to the harmonic p-combination and p-radial linear combination.
关键词 Star body intersection body star duality harmonic p-combination p-radial linear combination
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Land use suitability analysis for town development planning in Nanjing hilly areas: A case study of Tangshan new town, China 被引量:2
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作者 YANG Yang TANG Xiao-lan LI Zhe-hui 《Journal of Mountain Science》 SCIE CSCD 2021年第2期528-540,共13页
Land use suitability analysis plays an important role in sustainable land use and solving environmental problems caused by rapid urban development.A land use suitability mapping approach for town development planning ... Land use suitability analysis plays an important role in sustainable land use and solving environmental problems caused by rapid urban development.A land use suitability mapping approach for town development planning in hilly areas was constructed based on two multi-criteria evaluation methods:Weighted Linear Combination(WLC)and Ordered Weighted Averaging(OWA),to comparatively evaluate and map land use suitability of Tangshan new town in Nanjing,China.Fourteen evaluation factors related to topographic,environmental,socio-economics and historical sites data were used as suitability criteria.The analytic hierarchy process(AHP)method and GIS techniques were integrated into the evaluation models to create the land use suitability map for town development planning.The results of WLC approach showed that 11.4%of the total area is highly suitable while the 48.6%is unsuitable.The results of WLC and OWA approach showed the distribution of degree of land use suitability is almost the same.The areas located at the southern and eastern flat regions are highly suitable for land use,whereas the areas close to the mountain forests,steep slopes,waters,and hot springs,have lower suitability for land use.Sensitivity analysis indicated that the suitability results of the two proposed methods are robust.Indirect validation was achieved by mutual comparison of suitability maps derived from the WLC and OWA methods.It demonstrated that the overall agreement is 90.81%and kappa coefficient is 0.81,indicating that both methods provide very similar spatial suitability distributions.By overlaying the resultant map with the previous master plan map of Tangshan new town,the overlay map once again indicated a satisfactory ecological fit between the two maps.At last,several recommendations are proposed aiming at improving the long-term town development plan for Tangshan new town. 展开更多
关键词 Town Development Land use suitability Weighted linear combination Ordered weighted averaging Sensitivity analysis Tangshan new town
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Vibrational frequency of a strong-coupling polaron in a quantum rod at finite temperatures 被引量:2
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作者 丁朝华 肖景林 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期339-344,共6页
The Hamiltonian of a quantum rod with a boundary is presented after a coordinate transformation that changes the original ellipsoidal boundary into a spherical one. We then study the effect of temperature on the vibra... The Hamiltonian of a quantum rod with a boundary is presented after a coordinate transformation that changes the original ellipsoidal boundary into a spherical one. We then study the effect of temperature on the vibrational frequency and the ground state binding energy of the strong-coupling polaron in the rod. The two quantities are expressed as functions of the aspect ratio of the ellipsoid, the transverse and the longitudinal effective confinement lengths, the temperature and the electron-phonon coupling strength by linear combination operator and unitary transformation methods. It is found that the vibrational frequency and the ground state binding energy will increase rapidly with decreasing transverse and longitudinal effective confinement lengths. They are increasing functions of the electron- phonon coupling strength but become decreasing ones of the temperature and the aspect ratio. 展开更多
关键词 quantum rod POLARON temperature effect linear combination operator
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ON THE INVERTIBILITY OF HILBERT SPACE IDEMPOTENTS 被引量:2
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作者 邓春源 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期523-536,共14页
This note is to present some results on the group invertibility of linear combina- tions of idempotents when the difference of two idempotents is group invertible.
关键词 Group inverse linear combination of idempotents
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Landfill Siting Using GIS and AHP (Analytical Hierarchy Process): A Case Study AI-Qasim Qadhaa, Babylon, Iraq 被引量:1
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作者 Ali Jalil Chabuk Nadhir A1-Ansari +2 位作者 Hussain Musa Hussain Sven Knutsson Roland Pusch 《Journal of Civil Engineering and Architecture》 2016年第5期530-543,共14页
The selection of a landfill site is considered as a complicated task because this process is based on many factors and restrictions. For Al-Qasim Qadhaa, which is situated in the southern part of the Babylon Governora... The selection of a landfill site is considered as a complicated task because this process is based on many factors and restrictions. For Al-Qasim Qadhaa, which is situated in the southern part of the Babylon Governorate, Iraq, there is no landfill site in that area that conforms to the scientific criteria for selecting sites for landfill. For this reason, 15 criteria were adopted in this study (groundwater depth, rivers, soil types, agriculture lands use, land use, elevation, slope, gas pipelines, oil pipelines, power lines, roads, railways, urban centers, villages and archaeological sites) using GIS (geographic information system), which has a large ability to manage input data. In addition, the AHP (analytical hierarchy process) method was used to derive the relative weightings for each criterion using pair-wise comparison. To obtain the suitability index for candidate landfill sites, a weighted linear combination method was used. After combining these methods, two suitable candidate landfill sites, with areas of 2.766 km2 and 2.055 km2, respectively, were found to satisfy the scientific and environmental requirements. The area of these sites can accommodate solid waste from 2020 until 2030 based on the required area, which was 0.702 km2. 展开更多
关键词 LANDFILL AI-Qasim Qadhaa AHP (analytical hierarchy process) GIS WLC (weighted linear combination).
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COMPLETE MONOTONICITY FOR A NEW RATIO OF FINITELY MANY GAMMA FUNCTIONS
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作者 Feng QI 《Acta Mathematica Scientia》 SCIE CSCD 2022年第2期511-520,共10页
In this paper,by deriving an inequality involving the generating function of the Bernoulli numbers,the author introduces a new ratio of finitely many gamma functions,finds complete monotonicity of the second logarithm... In this paper,by deriving an inequality involving the generating function of the Bernoulli numbers,the author introduces a new ratio of finitely many gamma functions,finds complete monotonicity of the second logarithmic derivative of the ratio,and simply reviews the complete monotonicity of several linear combinations of finitely many digamma or trigamma functions. 展开更多
关键词 Bernoulli number RATIO generating function complete monotonicity gamma function digamma function trigamma function logarithmic derivative linear combination INEQUALITY
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