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Estimates on the eigenvalues of complex nonlocal Sturm-Liouville problems
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作者 SUN Fu LI Kun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第1期100-110,共11页
The present paper deals with the eigenvalues of complex nonlocal Sturm-Liouville boundary value problems.The bounds of the real and imaginary parts of eigenvalues for the nonlocal Sturm-Liouville differential equation... The present paper deals with the eigenvalues of complex nonlocal Sturm-Liouville boundary value problems.The bounds of the real and imaginary parts of eigenvalues for the nonlocal Sturm-Liouville differential equation involving complex nonlocal potential terms associated with nonlocal boundary conditions are obtained in terms of the integrable conditions of coefficients and the real part of the eigenvalues. 展开更多
关键词 Sturm-Liouville problem nonlocal potential complex valued coefficient non-real eigenvalue
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Assessment of ecosystem services value in response to prevailing and future land use/cover changes in Lahore,Pakistan 被引量:2
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作者 Mobeen Akhtar Yuanyuan Zhao +3 位作者 Guanglei Gao Qudsia Gulzar Azfar Hussain Abdus Samie 《Regional Sustainability》 2020年第1期37-47,共11页
Land use/cover changes(LUCCs)significantly affect ecosystem services(ESs)and their corresponding monetary value.ESs can be evaluated to analyze the ecological and environmental changes caused by LUCCs.This research ai... Land use/cover changes(LUCCs)significantly affect ecosystem services(ESs)and their corresponding monetary value.ESs can be evaluated to analyze the ecological and environmental changes caused by LUCCs.This research aims to estimate variations in the ecosystem services value(ESV)due to LUCCs in Lahore of Pakistan,and to offer information and recommendations to policy-makers concerned with the economic improvement of metropolis areas.We first investigated the historical LUCCs from 1990 to 2019,and then simulated the future land use/cover in 2030 and 2050 based on the CA-Markov model under three scenarios,including business-as-usual(BAU),rapid economic growth(REG),and coordinated environmental sustainability(CES).Subsequently,we evaluated the ESV from 1990 to 2050 and evaluated the historical and potential future ESV changes induced by LUCCs during 1990–2019 and 2019–2050,respectively.The results showed that,land use/cover exhibited an increase in built-up land and decreases in vegetation,water body,and unused land both in the past and future.The net ESV decreased from 58.26 million USD in 1990 to 50.31 million USD in 2019.In 2050,the decrease in ESV is most rapid under the REG scenario(decrease ESV of 7.13 million USD and decrease percentage of 14.18%),followed by the BAU(decrease ESV of 5.61 million USD and decrease percentage of 11.15%)and CES(decrease ESV of 5.18 million USD and decrease percentage of 10.30%)scenarios.For each ecosystem service type,the ESV of waste treatment decreased by 18.37%from 1990 to 2019,followed by soil formation and conservation(17.52%),biodiversity and maintenance(13.23%),climate regulation(11.80%),food production(11.69%),hydrological regulation(11.11%),and aesthetic value(3.07%).These outcomes indicate that continuous land use/cover planning should focus on regenerating aquatic areas and vegetation restoration. 展开更多
关键词 Ecosystem services Land use/cover changes Environmental sustainability CA Markov Urban expansion value coefficient
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Audit Committee, Value Creation Efficiency and Capital Employed Efficiency
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作者 Fanny Soewignyo Tonny Irianto Soewignyo 《Management Studies》 2018年第1期20-29,共10页
This study contributes a number of innovative and interesting empirical findings with a view of four audit committee characteristics to predict overall value creation efficiency and capital employed efficiency using v... This study contributes a number of innovative and interesting empirical findings with a view of four audit committee characteristics to predict overall value creation efficiency and capital employed efficiency using value added intellectual coefficient (VAICTM) method. Using purposive sampling, 34 property, real estate, and building construction firms listed on Indonesia Stock Exchange in 2011 were selected. Empirical findings could not provide a significant relationship between audit committee characteristics and the overall value creation efficiency as well as capital employed efficiency. This implies that currently, the number of members, number of meetings, number of independent commissioners, and accounting or finance expertise in audit committee cannot be expected as drivers of business value creation in Indonesian context, more specifically for property, real estate, and building construction industry. The overall lack of significant relationships may potentially result from limited human capacity, lack of financial expertise, and inadequate knowledge about the role of audit committee to add value to the business. 展开更多
关键词 audit committee capital employed efficiency VAICTM value added intellectual coefficient value creation efficiency
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Quantitative Comparison of Bile Acid Distribution and Intestinal Transport from Native Cow-bezoar and Artificial and in vitro Cultured Substitutes using Caco-2 Cell Monolayer Model 被引量:2
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作者 Ying CHEN Xiao-Ru HU +6 位作者 Xian-Long CHENG Shuang-Cheng MA Qing-Sen RAN Qing YANG Wei-Jie QIANG Zhong DAI Xiao-Xin ZHU 《Digital Chinese Medicine》 2018年第4期261-271,共11页
Objective This study was conducted to examine the absorption and translocation of conjugated bile acids(BAs)in Calculus bovis and its substitutes to detect differences in these materials.Methods A Caco-2 monolayer cel... Objective This study was conducted to examine the absorption and translocation of conjugated bile acids(BAs)in Calculus bovis and its substitutes to detect differences in these materials.Methods A Caco-2 monolayer cell model was used to compare the apparent permeability coefficient(Papp)value and efflux ratio(ER)of BAs in natural cow-bezoar(NCB),artificial cow-bezoar(ACB),and in vitro cultured cow-bezoar(Ivt-CCB).Papp and ER values were determined by liquid chromatography-mass spectrometry.Samples were separated on an analytical column.Results The distribution of BAs in NCB was significantly different from that in ACB and Ivt-CCB.The percentages of conjugated BAs were significantly higher in NCB than in the two substitutes.The distribution differences of conjugated and unconjugated BAs can be used to distinguish costly NCB from relatively inexpensive substitutes.Conclusion The transport characteristics of BAs in Ivt-CCB were more consistent with NCB than with ACB,even when the proportions of BAs in Ivt-CCB were closer to those of ACB. 展开更多
关键词 Bile acids Cow-bezoar Intestinal transport Caco-2 cell Apparent permeability coefficient value Efflux ratio
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A DUAL COUPLED METHOD FOR BOUNDARY VALUE PROBLEMS OF PDE WITH COEFFICIENTS OF SMALL PERIOD 被引量:17
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作者 J.Z. Cui H.Y. Yang(Institute of Computational Mathematics and Scientific/Engineering Computing,Chinese Academy of Sciences, Beijing, China) 《Journal of Computational Mathematics》 SCIE CSCD 1996年第2期159-174,共16页
In this paper the homogenization method is improved to develop one kind of dual coupled approximate method, which reflects both the macro-scope properties of whole structure and its loadings, and micro-scope configura... In this paper the homogenization method is improved to develop one kind of dual coupled approximate method, which reflects both the macro-scope properties of whole structure and its loadings, and micro-scope configuration properties of composite materials. The boundary value problem of woven membrane is considered, the dual asymptotic expression of the exact solution is given, and its approximation and error estimation are discussed. Finally the numerical example shows the effectiveness of this dual coupled method. 展开更多
关键词 PDE A DUAL COUPLED METHOD FOR BOUNDARY value PROBLEMS OF PDE WITH coefficientS OF SMALL PERIOD
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An Alternative Method to Study Wave Scattering by Semi-infinite Inertial Surfaces
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作者 R.Gayen Ranita Roy 《Journal of Marine Science and Application》 2013年第1期31-37,共7页
A new method to solve the boundary value problem arising in the study of scattering of two-dimensional surface water waves by a discontinuity in the surface boundary conditions is presented in this paper. The disconti... A new method to solve the boundary value problem arising in the study of scattering of two-dimensional surface water waves by a discontinuity in the surface boundary conditions is presented in this paper. The discontinuity arises due to the floating of two semi-infinite inertial surfaces of different surface densities. Applying Green's second identity to the potential functions and appropriate Green's functions, this problem is reduced to solving two coupled Fredholm integral equations with regular kernels. The solutions to these integral equations are used to determine the reflection and the transmission coefficients. The results for the reflection coefficient are presented graphically and are compared to those obtained earlier using other research methods. It is observed from the graphs that the results computed from the present analysis match exactly with the previous results. 展开更多
关键词 Fredholm integral equations inertial surface reflection coefficient water wave scattering boundary value problem
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The Grid Algorithm of the Development Coefficient and the Combination Coefficient of Background Value in GM(1,1) Model
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作者 Jianhua Liu Yong Wei 《Journal of Systems Science and Information》 2008年第1期91-96,共6页
This article gives the algorithm of the sector in which the development coefficient is, and the steps to simultaneously calculate the development coefficient and combination coefficient of background value. Unifying t... This article gives the algorithm of the sector in which the development coefficient is, and the steps to simultaneously calculate the development coefficient and combination coefficient of background value. Unifying the development coefficient and the background value's coefficient of combination to optimize the model together, avoiding the malpractice to separate the two in traditional method, and avoiding the error brought out by matrix multiplication because of matrix's illness and so on in the traditional way, therefore increases the precision of the model. 展开更多
关键词 GM(1 1) model development coefficient grid algorithm combination coefficient of background value
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Diagnostic Utility of Diffusion-weighted Magnetic Resonance Imaging in Differentiating Small Solid Renal Tumors (≤4 cm) at 3.0T Magnetic Resonance Imaging 被引量:4
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作者 Han-Mei Zhang Ying-Hua Wu +8 位作者 Qi Gan Xiao Lyu Xiang-Lan Zhu Min Kuang Rong-Bo Liu Zi-Xing Huang ang Yuan Xi-Jiao Liu Bin Song 《Chinese Medical Journal》 SCIE CAS CSCD 2015年第11期1444-1449,共6页
Background: The aim of this study was to assess the performance of apparent diffusion coefficient (ADC) measurement obtained with diffusion-weighted magnetic resonance imaging (DW-MRI) to distinguish renal cell c... Background: The aim of this study was to assess the performance of apparent diffusion coefficient (ADC) measurement obtained with diffusion-weighted magnetic resonance imaging (DW-MRI) to distinguish renal cell carcinomas (RCCs) from small benign solid renal tumors (〈4 cm). Methods: In this cross-sectional study, 49 consecutive patients with histopathologically confirmed small solid renal tumors, and seven healthy volunteers were imaged using nonenhanced MRI and DW-MRI. The ADC map was calculated using the b values of 0, 50, 400, and 600 s/ mm2 and values compared via the Kruskal-Wallis and Mann-Whitney tests. The utility of ADC for differentiating RCCs and benign lesions was assessed using a receiver operating characteristic curve. Multiple nonenhanced MRI features were analyzed by Logistic regression. Results: The tumors consisted of 33 cases of clear-cell RCCs (ccRCCs) and 16 cases of benign tumors, including 14 cases of minimal fat angiomyolipomas and 2 cases ofoncocytomas. The ADCs showed significant differences among benign tumors ([0.90 ±0.52] x 10 x mm2/s), ccRCCs ([1.53 ± 0.31 ] x 10 ^3 mm2/s) and the normal renal parenchyma ([2.22 ± 0.12]x 10^-3 mmVs) (P 〈 0.001). Moreover, there was statistically significant difference between high and low-grade ccRCCs (P = 0.004). Using a cut-offADC of 1.36± 10 3 mm2/s, DW-MRI resulted in an area under the curve (AUC), sensitivity, and specificity equal to 0.839, 75.8%, and 87.5%, respectively. Nonenhanced MRI alone and the combination of imaging methods led to an AUC, sensitivity and specificity equal to 0.919, 93.9%, and 81.2%, 0.998, 97%, and 100%, respectively. The Logistic regression showed that the location of the center of the tumor (inside the contour of the kidney) and appearance of stiffblood vessel were significantly helpful for diagnosing ccRCCs. Conclusions: DW-MRI has potential in distinguishing ccRCCs from benign lesions in human small solid renal tumors (〈4 cm), and in increasing the accuracy for diagnosing ccRCCs when combined with nonenhanced MRI. 展开更多
关键词 Apparent Diffusion coefficient value Diffusion-weighted Magnetic Resonance Imaging Renal Cell Carcinomas Renal Tumors
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Evaluation of the malignant potential of gliomas using diffusion-weighted and gadolinium-enhanced magnetic resonance imaging 被引量:1
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作者 Yoshinori Takaya Hui Chen +5 位作者 Hirotomo TEN Katsumi Hoya Chuan-lu Jiang Ken-ichi Oyama Keisuke Onoda Akira Matsuno 《Brain Science Advances》 2021年第4期248-256,共9页
Objective:This study aimed to determine whether the apparent diffusion coefficients(ADCs)determined by diffusion-weighted imaging(DWI)of magnetic resonance imaging(MRI)could facilitate the malignancy grading of variou... Objective:This study aimed to determine whether the apparent diffusion coefficients(ADCs)determined by diffusion-weighted imaging(DWI)of magnetic resonance imaging(MRI)could facilitate the malignancy grading of various gliomas.Methods:Sixty patients with a primary cerebral glioma underwent diffusion-weighted and gadolinium-enhanced(Gd)T1-weighted MRI using a 1.5-T MRI scanner.Scoring was performed based on signal intensities on DWI and Gd images.The mean and minimum ADC values were calculated,and Ki-67 staining was performed for each histological sample to evaluate their tumor proliferative potential.Then,the DWI,Gd,and combined scores were analyzed and compared with the Ki-67 staining index and malignant grade.The relationships among the mean and minimum ADC values,Ki-67staining index,and malignant grade were also evaluated.Results:The minimum ADC was inversely correlated with the Ki-67staining index,with a low minimum ADC suggestive of tumor malignancy.The qualitative evaluation of the D score of water molecule diffusion on DWI accurately reflected the pathological grades of gliomas,with an effectiveness that was at least as good as the quantitative analysis using the minimum ADC.The diagnostic value of Gd images in determining glioma malignancy grades was inferior to that of DWI.Conclusion:Both DWI and gadolinium-enhanced images of MRI should be considered essential for the diagnosis of tumor malignancy. 展开更多
关键词 apparent diffusion coefficient value diffusionweighted imaging GLIOMA MALIGNANCY
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A New Method to Calculate Investment Multiplier 被引量:1
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作者 YANG Cui\|hong Institute of Systems Sciencex, CAS, Beijing 100080, China 《Systems Science and Systems Engineering》 CSCD 1999年第4期116-119,共4页
Based on the analysis of Keynesian investment theory, this paper puts forward the method of calculating investment multiplier with partial\|closed input\|output model, and by using 1995 input\|output table of China, ... Based on the analysis of Keynesian investment theory, this paper puts forward the method of calculating investment multiplier with partial\|closed input\|output model, and by using 1995 input\|output table of China, calculates the investment multiplier. 展开更多
关键词 investment multiplier partial\|closed input\|output model value\|added coefficient
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