Data Envelopment Analysis(DEA) and Ratio Analysis(RA) are two widely used methods for measuring units' productivity and any other criteria that could be assessed based on the available input and output variables....Data Envelopment Analysis(DEA) and Ratio Analysis(RA) are two widely used methods for measuring units' productivity and any other criteria that could be assessed based on the available input and output variables.A number of researchers have studied DEA and RA and noted the positive and negative differences between them.Aggregated ratio analysis(ARA) model,which provide an important linkage between DEA and RA theory,is equivalent to the CCR DEA model,and this equivalence property offers a great deal of opportunities for DEA to be interpreted and applied in different ways.This paper extends the results of ARA model and proposes an extended aggregated ratio analysis(EARA) model,similar as the development from CCR model to BCC model in DEA context.The proposed model can offer an insight into the characteristic of returns to scale,playing the corresponding role as BCC model does.The numerical example is revisited in the paper and the results are compared.展开更多
This paper is aiming to evaluate the effect of cost control strategy on the profitability of Coca-Cola Company from year 2015 to 2017 by using the ratio analysis and offer essential recommendations for the company.Thi...This paper is aiming to evaluate the effect of cost control strategy on the profitability of Coca-Cola Company from year 2015 to 2017 by using the ratio analysis and offer essential recommendations for the company.This paper is divided into three parts.First part is to introduce the current business operation activities and basic background information.This paper adopts desk research as data collection method.The major sources of information are the annual report of Coca-Cola Company,the database of World Health Organisation and other scholastic websites such as Wan Fang Database.Second,financial statements analysis and profitability analysis.This part contains three data analysis methods that are horizontal analysis and ratio analysis.Third part is the conclusion which is from year 2015 to 2017,that Coca-Cola Company has strengthened its profitability through cost control strategy but there are fatal hazards in the profitability of Coca-Cola Company that is the worse utilization of its assets to generate profit and dispute with IRS.The recommendations are also provided based on the conclusion which could be referenced by other companies to some extent.展开更多
The over-load protective relay is widely used directly affects the safe running of a motor. The reliability for motor protection. The reliability of the over-load protective relay testing and reliability analysis of t...The over-load protective relay is widely used directly affects the safe running of a motor. The reliability for motor protection. The reliability of the over-load protective relay testing and reliability analysis of the over-load protective relay is an important way to improve the reliability of products. In this paper, the reliability test method of the over-load protective relay is studied, and the reliability tests of the typical products are carried out on a reliability tester developed by authors. In terms of the testing results, the reliability analysis is finished. The failure reasons are found and the measures are put forward to improve the reliability of the products.展开更多
Materials with a negative Poisson's ratio(PR)are called auxetics;they are characterized by expansion/contraction when tensioned/compressed.Given this counterintuitive behavior,they present very particular character...Materials with a negative Poisson's ratio(PR)are called auxetics;they are characterized by expansion/contraction when tensioned/compressed.Given this counterintuitive behavior,they present very particular characteristics and mechanical behavior.Geometrical models have been developed to justify and artificiall reproduce such materials' auxetic behavior.The focus of this study is the exploration of a reentrant model by analyzing the variation in the PR of reentrant structures as a function of geometrical and base material parameters.It is shown that,even in the presence of protruding ribs,there may not be auxetic behavior,and this depends on the geometry of each reentrant structure.Values determined for these parameters can be helpful as approximate reference data in the design and fabrication of auxetic lattices using reentrant geometries.展开更多
Soil carbon to nitrogen(C/N) ratio is one of the most important variables reflecting soil quality and ecological function,and an indicator for assessing carbon and nitrogen nutrition balance of soils.Its variation ref...Soil carbon to nitrogen(C/N) ratio is one of the most important variables reflecting soil quality and ecological function,and an indicator for assessing carbon and nitrogen nutrition balance of soils.Its variation reflects the carbon and nitrogen cycling of soils.In order to explore the spatial variability of soil C/N ratio and its controlling factors of the Ili River valley in Xinjiang Uygur Autonomous Region,Northwest China,the traditional statistical methods,including correlation analysis,geostatistic alanalys and multiple regression analysis were used.The statistical results showed that the soil C/N ratio varied from 7.00 to 23.11,with a mean value of 10.92,and the coefficient of variation was 31.3%.Correlation analysis showed that longitude,altitude,precipitation,soil water,organic carbon,and total nitrogen were positively correlated with the soil C/N ratio(P < 0.01),whereas negative correlations were found between the soil C/N ratio and latitude,temperature,soil bulk density and soil p H.Ordinary Cokriging interpolation showed that r and ME were 0.73 and 0.57,respectively,indicating that the prediction accuracy was high.The spatial autocorrelation of the soil C/N ratio was 6.4 km,and the nugget effect of the soil C/N ratio was 10% with a patchy distribution,in which the area with high value(12.00–20.41) accounted for 22.6% of the total area.Land uses changed the soil C/N ratio with the order of cultivated land > grass land > forest land > garden.Multiple regression analysis showed that geographical and climatic factors,and soil physical and chemical properties could independently explain 26.8%and 55.4% of the spatial features of soil C/N ratio,while human activities could independently explain 5.4% of the spatial features only.The spatial distribution of soil C/N ratio in the study has important reference value for managing soil carbon and nitrogen,and for improving ecological function to similar regions.展开更多
To extract vegetation pigment concentration and physiological status has been studied in two test areas covered with swamp and flourish vegetation using pushbroom hyperspectral imager (PHI) data which flied in Septemb...To extract vegetation pigment concentration and physiological status has been studied in two test areas covered with swamp and flourish vegetation using pushbroom hyperspectral imager (PHI) data which flied in September of 2000 at Daxing'anling district of Heilongjiang Province, China. The ratio analysis of reflectance spectra (RARS) indices, which were put forward by Chappelle et al (1992), are chosen in this paper owing to their effect and simpleness against both comparison with various methods and techniques for exploration of pigment concentration and characteristics of PHI data. The correlation coefficients between RARS indices and pigment concentration of vegetation were up to 0.8. The new RARS indices modes are established in the two test areas using both PHI data and spectra of different vegetations measured in the field. The indices' parameter images of chlorophyll a (Chl a), chlorophyll b (Chl b) and carotenoids (Cars) of the test areas covered with swamp and flourish vegetation are acquired by the new RARS indices modes. Furthermore, the regional concentration of Chl a and Chl b are extracted and quantified using regression equations between RARS indices and pigment concentrations, which were built by Blackburn (1998). The results showed the physiological status and variety clearly, and are in good agreement with the distribution of vegetation in the field.展开更多
In this paper,a research was conducted on the design technology of continuous beam-arch composite bridges.A brief introduction is given on the of continuous beam-arch composite bridges,its basic mechanical characteris...In this paper,a research was conducted on the design technology of continuous beam-arch composite bridges.A brief introduction is given on the of continuous beam-arch composite bridges,its basic mechanical characteristics is analyzed,and three aspects of design technology is studied,which are rise-span ratio,stiffness ratio,and bridge deck cracking.This article acts as a reference for relevant design units in China to improve the design of continuous beam-arch combination bridges.展开更多
As threats of landslide hazards have become gradually more severe in recent decades,studies on landslide prevention and mitigation have attracted widespread attention in relevant domains.A hot research topic has been ...As threats of landslide hazards have become gradually more severe in recent decades,studies on landslide prevention and mitigation have attracted widespread attention in relevant domains.A hot research topic has been the ability to predict landslide susceptibility,which can be used to design schemes of land exploitation and urban development in mountainous areas.In this study,the teaching-learning-based optimization(TLBO)and satin bowerbird optimizer(SBO)algorithms were applied to optimize the adaptive neuro-fuzzy inference system(ANFIS)model for landslide susceptibility mapping.In the study area,152 landslides were identified and randomly divided into two groups as training(70%)and validation(30%)dataset.Additionally,a total of fifteen landslide influencing factors were selected.The relative importance and weights of various influencing factors were determined using the step-wise weight assessment ratio analysis(SWARA)method.Finally,the comprehensive performance of the two models was validated and compared using various indexes,such as the root mean square error(RMSE),processing time,convergence,and area under receiver operating characteristic curves(AUROC).The results demonstrated that the AUROC values of the ANFIS,ANFIS-TLBO and ANFIS-SBO models with the training data were 0.808,0.785 and 0.755,respectively.In terms of the validation dataset,the ANFISSBO model exhibited a higher AUROC value of 0.781,while the AUROC value of the ANFIS-TLBO and ANFIS models were 0.749 and 0.681,respectively.Moreover,the ANFIS-SBO model showed lower RMSE values for the validation dataset,indicating that the SBO algorithm had a better optimization capability.Meanwhile,the processing time and convergence of the ANFIS-SBO model were far superior to those of the ANFIS-TLBO model.Therefore,both the ensemble models proposed in this paper can generate adequate results,and the ANFIS-SBO model is recommended as the more suitable model for landslide susceptibility assessment in the study area considered due to its excellent accuracy and efficiency.展开更多
The purpose of this paper is to advance the interpretation of the Du Pont Equation, which is commonly used in the financial statements analysis of corporations. The paper makes a special interpretation of the three te...The purpose of this paper is to advance the interpretation of the Du Pont Equation, which is commonly used in the financial statements analysis of corporations. The paper makes a special interpretation of the three terms which appear in the Du Pont Equation that provides an understanding of the overall financial standing of the corporation under consideration. As a result of this interpretation, the order in which f'mancial statements analysis is commonly performed should be reversed. That is, in financial statements analysis, one should start with the analysis of the Du Pont Equation, to gain an overall understanding of the financial situation of the corporation; and then, perform the ratio analysis, to gain a detailed understanding of the financial situation of the corporation. This order of analysis is in contrast to the order in which financial statements analysis is commonly performed, i.e., first, the ratio analysis is performed, and then, the Du Pont Equation is analyzed.展开更多
Optimization of capital structure has been a famous issue in Corporate Finance.It is essential for modern companies to find the optional capital structure of themselves because it could help these companies to reduce ...Optimization of capital structure has been a famous issue in Corporate Finance.It is essential for modern companies to find the optional capital structure of themselves because it could help these companies to reduce the cost of finance.This best structure is not easy to find out due to the complex determinants behind it.However,there still are some alternative ways could be used to judge whether a company reach its optional capital structure.This report takes X company as an example to discuss that how to use different efficient methods to estimate the optional capital structure of a company.展开更多
Particle size distribution of coarse aggregates through mechanical sieving gives results in terms of cumu- lative mass percent. But digital image processing generated size distribution of particles, while being fast a...Particle size distribution of coarse aggregates through mechanical sieving gives results in terms of cumu- lative mass percent. But digital image processing generated size distribution of particles, while being fast and accurate, is often expressed in terms of area function or number of particles. In this paper, a mass model is developed which converts the image obtained size distribution to mass-wise distribution, mak- ing it readily comparable to mechanical sieving data. The concept of weight/particle ratio is introduced for mass reconstruction from 2D images of particle aggregates. Using this mass model, the effects of several particle shape parameters (such as major axis, minor axis, and equivalent diameter) on sieve-size of the particles is studied. It is shown that the sieve-size of a particle strongly depend upon the shape param- eters, 91% of its variation being explained by major axis, minor axis, bounding box length and equivalent diameter. Furthermore, minor axis gives an overall accurate estimate of particle sieve-size, error in mean size (D-50) being just 0.4%. However, sieve-size of smaller particles (〈20 ram) strongly depends upon the length of the smaller arm of the bounding box enclosing them and sieve-sizes of larger particles (〉20 mm) are highly correlated to their equivalent diameters. Multiple linear regression analysis has been used to generate overall mass-wise particle size distribution, considering the influences of all these shape parameters on particle sieve-size. Multiple linear regression generated overall mass-wise particle size distribution shows a strong correlation with sieve generated data. The adjusted R-square value of the regression analysis is found to be 99 percent (w.r,t cumulative frequency). The method proposed in this paper provides a time-efficient way of producing accurate (up to 99%) mass-wise PSD using digital image processing and it can be used effectively to renlace the mechanical sieving.展开更多
Several pupil filtering techniques have been developed in the last few years to obtain transverse superresolution (a narrower point spread function core). Such a core decrease entails two relevant limitations: a de...Several pupil filtering techniques have been developed in the last few years to obtain transverse superresolution (a narrower point spread function core). Such a core decrease entails two relevant limitations: a decrease of the peak intensity and an increase of the sidelobe intensity. Here, we calculate the Strehl ratio as a function of the core size for the most used binary phase filters. Furthermore, we show that this relation approaches the fundamental limit of the attainable Strehl ratio at the focal plane for any filter. Finally, we show the calculation of the peak-to-sidelobe ratio in order to check the system viability in every application.展开更多
A new simple spectrophotometric method was developed for the determination of binary mixtures without prior separation.The method is based on the generation of ratio spectra of compound X by using a standard spectrum ...A new simple spectrophotometric method was developed for the determination of binary mixtures without prior separation.The method is based on the generation of ratio spectra of compound X by using a standard spectrum of compound Y as a divisor.The peak to trough amplitudes between two selected wavelengths in the ratio spectra are proportional to concentration of X without interference from Y.The method was demonstrated by determination of two drug combinations.The first consists of the two antihyperlipidemics:atorvastatin calcium(ATV) and ezetimibe(EZE),and the second comprises the antihypertensives:candesartan cilexetil(CAN) and hydrochlorothiazide(HCT).For mixture 1,ATV was determined using 10 μg/mL EZE as the divisor to generate the ratio spectra,and the peak to trough amplitudes between 231 and 276 nm were plotted against ATV concentration.Similarly,by using 10 μg/mL ATV as divisor,the peak to trough amplitudes between 231 and 276 nm were found proportional to EZE concentration.Calibration curves were linear in the range 2.5-40 mg/mL for both drugs.For mixture 2,divisor concentration was 7.5 μg/mL for both drugs.CAN was determined using its peak to trough amplitudes at 251 and 277 nm,while HCT was estimated using the amplitudes between 251 and 276 nm.The measured amplitudes were linearly correlated to concentration in the ranges 2.5-50 and 1-30 μg/mL for CAN and HCT,respectively.The proposed spectrophotometric method was validated and successfully applied for the assay of both drug combinations in several laboratory-prepared mixtures and commercial tablets.展开更多
Since it is a gradual process for listed companies to plunge into financial failure, it is desirable to discern tho potential risks in advance. This paper, with the adoption of multiple discriminant analyzing approach...Since it is a gradual process for listed companies to plunge into financial failure, it is desirable to discern tho potential risks in advance. This paper, with the adoption of multiple discriminant analyzing approach, tries to find out optimal variables and financial failure predicting model for Chinese listed companies based on audited accounting data.展开更多
The process of economic activities is on the basis of tremendous material inputs.China has been discharging an enormous amount of waste,giving rise to a wide range of environmental impacts.The method of economy-wide m...The process of economic activities is on the basis of tremendous material inputs.China has been discharging an enormous amount of waste,giving rise to a wide range of environmental impacts.The method of economy-wide material flow analysis(EW-MFA)is one of the effective tools to examine the flow of materials entering physical economies,and recognize early environmental problems.Relevant researches are still at the early stage in China and most focus on material throughput but are rarely concerned about the utilization of recycling resource and environmental impact.Based on more than 3,000 items of data related,materials entering Chinese economy are classified into three types,and then the characteristics of material input and environmental impact are presented for the years 1990-2005 by using the indicators derived from EW-MFA.The Ratio of Recycled Material(RRM) is added as the new indicator in order to be in accordance with the need of circular economy being promoted in China.Results show that the great changes in the structure of material input cause the continuous increase of industrial solid waste emissions and the bogging down of material productivity.The RRM reveals that the utilization of recycling resources remains at a fairly low level in China.Finally,some weakness of EW-MFA is discussed according to the calculated results.展开更多
Background: Tertiary hospitals serve as the medical service center within the region and play an important role in the medical and health service system. They are also the key targets of public hospital reform in the...Background: Tertiary hospitals serve as the medical service center within the region and play an important role in the medical and health service system. They are also the key targets of public hospital reform in the new era in China. Through the reform of health system, the public hospital efficiency has changed remarkably. Therefore, this study aimed to provide some advice for efficiency assessment of public hospitals in China by comparing and analyzing the consistency of results obtained by three commonly used methods for examining hospital efficiency, that is, ratio analysis (RA), stochastic frontier analysis (SFA), and data envelopment analysis (DEA). Methods: The theoretical basis, operational processes, and the application status of RA, SFA, and DEA were learned through literature analysis. Then, the empirical analysis was conducted based on measured data from 51 tertiary public hospitals in Beijing from 2009 to 2011. Results: The average values of hospital efficiency calculated by SFA with index screening and principal component analysis (PCA) results and those calculated by DEA with index screening results were relatively stable. The efficiency of specialized hospitals was higher than that of general hospitals and that of traditional Chinese medicine hospitals. The results obtained by SFA with index screening results and the results obtained by S FA with PCA results showed a relatively high correlation (r-value in 2009, 2010, and 2011 were 0.869, 0.753, and 0.842, respectively, P 〈 0.01). The correlation between results obtained by DEA with index screening results and PCA results and results obtained by other methods showed statistical significance, but the correlation between results obtained by DEA with index screening results and PCA results was lower than that between results obtained by SFA with index screening results and PCA results. Conclusions: RA is not suitable for multi-index evaluation of hospital efficiency. In the given conditions, SFA is a stable efficiency analysis method. In the evaluation of hospital efficiency, DEA combined with PCA should be adopted with caution due to its poor stability.展开更多
Background Lymph node ratio (LNR) has recently been reported as a potential prognostic marker in many malignant diseases. We aimed to analyze the potential prognostic effect of LNR on hypopharyngeal squamous cell ca...Background Lymph node ratio (LNR) has recently been reported as a potential prognostic marker in many malignant diseases. We aimed to analyze the potential prognostic effect of LNR on hypopharyngeal squamous cell carcinoma (HPSCC) after neoadjuvant therapy in our institution.展开更多
The problem of large-scale charging of electric vehicles(EVs)with consumer-imposed charging deadlines is considered.An architecture for the intelligent energy management system(iEMS)is introduced.The iEMS consists of ...The problem of large-scale charging of electric vehicles(EVs)with consumer-imposed charging deadlines is considered.An architecture for the intelligent energy management system(iEMS)is introduced.The iEMS consists of an admission control and pricing module,a scheduling module that determines the charging sequence,and a power dispatch module that draws power from a mix of storage,local renewable energy sources,and purchased power from the grid.A threshold admission and greedy scheduling(TAGS)policy is proposed to maximize operation profit.The performance of TAGS is analyzed and evaluated based on average and worst-case performance measures and the optimality of TAGS is established for some instances.Numerical simulations demonstrate that TAGS achieves noticeable performance gains over benchmark techniques.展开更多
The strategy of choosing suitable plants should receive great performance in phytoremediation of surface water polluted by triazophos (O,O-diethyl-O-(1-phenyl- 1,2,4-triazol-3-base) sulfur phosphate, TAP), which i...The strategy of choosing suitable plants should receive great performance in phytoremediation of surface water polluted by triazophos (O,O-diethyl-O-(1-phenyl- 1,2,4-triazol-3-base) sulfur phosphate, TAP), which is an organophosphorus pesticide widespread applied for agriculture in China and moderately toxic to higher animal and fish. The tolerance, uptake, transformation and removal of TAP by twelve species of macrophytes were examined in a hydroponic system and a comprehensive score (CS) of five parameters (relative growth rate (RGR), biomass, root/shoot ratio, removal capacity (RC), and bio-concentration factor (BCF)) by factor analysis was employed to screen the potential macrophyte species for TAP phytoremediation. The results showed that Thalia dealbata, Cyperus alternifolius, Canna indica and Acorus calamus had higher RGR values, indicating these four species having stronger growth capacity under TAP stress. The higher RC loading in Iris pseudacorus and Cyperus rotundus were 42.11 and 24.63μg/(g fw.day), respectively. The highest values of BCF occurred in A. calamus (1.17), and TF occurred in Eichhornia crassipes (2.14). Biomass and root/shoot ratio of plant showed significant positive correlation with first-order kinetic constant of TAP removal in the hydroponic system, indicating that plant biomass and root system play important roles in remediation of TAP. Five plant species including C. alternifolius, A. calamus, T. dealbata, C. indica and Typha orientalis, which owned higher CS, would be potential species for TAP phytoremediation of contaminated water bodies.展开更多
基金support by National Natural Science Foundation of P.R.C. (70901069)Ministry of Education Foundation of Humanities and Social Sciences of P.R.C. (10YJC630208)+1 种基金Key Foundation of Natural Science for Colleges and Universities in Anhui, China (KJ2011A001) Social Science Foundation of Anhui, China (AHSK07-08D25, AHSKF09-10D116, AHSK09-10D14)
文摘Data Envelopment Analysis(DEA) and Ratio Analysis(RA) are two widely used methods for measuring units' productivity and any other criteria that could be assessed based on the available input and output variables.A number of researchers have studied DEA and RA and noted the positive and negative differences between them.Aggregated ratio analysis(ARA) model,which provide an important linkage between DEA and RA theory,is equivalent to the CCR DEA model,and this equivalence property offers a great deal of opportunities for DEA to be interpreted and applied in different ways.This paper extends the results of ARA model and proposes an extended aggregated ratio analysis(EARA) model,similar as the development from CCR model to BCC model in DEA context.The proposed model can offer an insight into the characteristic of returns to scale,playing the corresponding role as BCC model does.The numerical example is revisited in the paper and the results are compared.
文摘This paper is aiming to evaluate the effect of cost control strategy on the profitability of Coca-Cola Company from year 2015 to 2017 by using the ratio analysis and offer essential recommendations for the company.This paper is divided into three parts.First part is to introduce the current business operation activities and basic background information.This paper adopts desk research as data collection method.The major sources of information are the annual report of Coca-Cola Company,the database of World Health Organisation and other scholastic websites such as Wan Fang Database.Second,financial statements analysis and profitability analysis.This part contains three data analysis methods that are horizontal analysis and ratio analysis.Third part is the conclusion which is from year 2015 to 2017,that Coca-Cola Company has strengthened its profitability through cost control strategy but there are fatal hazards in the profitability of Coca-Cola Company that is the worse utilization of its assets to generate profit and dispute with IRS.The recommendations are also provided based on the conclusion which could be referenced by other companies to some extent.
基金Project (No. E2005000039) supported by the Natural Science Foun-dation of Hebei Province, China
文摘The over-load protective relay is widely used directly affects the safe running of a motor. The reliability for motor protection. The reliability of the over-load protective relay testing and reliability analysis of the over-load protective relay is an important way to improve the reliability of products. In this paper, the reliability test method of the over-load protective relay is studied, and the reliability tests of the typical products are carried out on a reliability tester developed by authors. In terms of the testing results, the reliability analysis is finished. The failure reasons are found and the measures are put forward to improve the reliability of the products.
文摘Materials with a negative Poisson's ratio(PR)are called auxetics;they are characterized by expansion/contraction when tensioned/compressed.Given this counterintuitive behavior,they present very particular characteristics and mechanical behavior.Geometrical models have been developed to justify and artificiall reproduce such materials' auxetic behavior.The focus of this study is the exploration of a reentrant model by analyzing the variation in the PR of reentrant structures as a function of geometrical and base material parameters.It is shown that,even in the presence of protruding ribs,there may not be auxetic behavior,and this depends on the geometry of each reentrant structure.Values determined for these parameters can be helpful as approximate reference data in the design and fabrication of auxetic lattices using reentrant geometries.
基金Under the auspices of National Science and Technology Support Program of China(No.2014BAC15B03)the West Light Funds of Chinese Academy of Sciences(No.YB201302)
文摘Soil carbon to nitrogen(C/N) ratio is one of the most important variables reflecting soil quality and ecological function,and an indicator for assessing carbon and nitrogen nutrition balance of soils.Its variation reflects the carbon and nitrogen cycling of soils.In order to explore the spatial variability of soil C/N ratio and its controlling factors of the Ili River valley in Xinjiang Uygur Autonomous Region,Northwest China,the traditional statistical methods,including correlation analysis,geostatistic alanalys and multiple regression analysis were used.The statistical results showed that the soil C/N ratio varied from 7.00 to 23.11,with a mean value of 10.92,and the coefficient of variation was 31.3%.Correlation analysis showed that longitude,altitude,precipitation,soil water,organic carbon,and total nitrogen were positively correlated with the soil C/N ratio(P < 0.01),whereas negative correlations were found between the soil C/N ratio and latitude,temperature,soil bulk density and soil p H.Ordinary Cokriging interpolation showed that r and ME were 0.73 and 0.57,respectively,indicating that the prediction accuracy was high.The spatial autocorrelation of the soil C/N ratio was 6.4 km,and the nugget effect of the soil C/N ratio was 10% with a patchy distribution,in which the area with high value(12.00–20.41) accounted for 22.6% of the total area.Land uses changed the soil C/N ratio with the order of cultivated land > grass land > forest land > garden.Multiple regression analysis showed that geographical and climatic factors,and soil physical and chemical properties could independently explain 26.8%and 55.4% of the spatial features of soil C/N ratio,while human activities could independently explain 5.4% of the spatial features only.The spatial distribution of soil C/N ratio in the study has important reference value for managing soil carbon and nitrogen,and for improving ecological function to similar regions.
文摘To extract vegetation pigment concentration and physiological status has been studied in two test areas covered with swamp and flourish vegetation using pushbroom hyperspectral imager (PHI) data which flied in September of 2000 at Daxing'anling district of Heilongjiang Province, China. The ratio analysis of reflectance spectra (RARS) indices, which were put forward by Chappelle et al (1992), are chosen in this paper owing to their effect and simpleness against both comparison with various methods and techniques for exploration of pigment concentration and characteristics of PHI data. The correlation coefficients between RARS indices and pigment concentration of vegetation were up to 0.8. The new RARS indices modes are established in the two test areas using both PHI data and spectra of different vegetations measured in the field. The indices' parameter images of chlorophyll a (Chl a), chlorophyll b (Chl b) and carotenoids (Cars) of the test areas covered with swamp and flourish vegetation are acquired by the new RARS indices modes. Furthermore, the regional concentration of Chl a and Chl b are extracted and quantified using regression equations between RARS indices and pigment concentrations, which were built by Blackburn (1998). The results showed the physiological status and variety clearly, and are in good agreement with the distribution of vegetation in the field.
文摘In this paper,a research was conducted on the design technology of continuous beam-arch composite bridges.A brief introduction is given on the of continuous beam-arch composite bridges,its basic mechanical characteristics is analyzed,and three aspects of design technology is studied,which are rise-span ratio,stiffness ratio,and bridge deck cracking.This article acts as a reference for relevant design units in China to improve the design of continuous beam-arch combination bridges.
基金supported by the National Natural Science Foundation of China(Grant Nos.41807192,41790441)Innovation Capability Support Program of Shaanxi(Grant No.2020KJXX-005)Natural Science Basic Research Program of Shaanxi(Grant Nos.2019JLM-7,2019JQ-094)。
文摘As threats of landslide hazards have become gradually more severe in recent decades,studies on landslide prevention and mitigation have attracted widespread attention in relevant domains.A hot research topic has been the ability to predict landslide susceptibility,which can be used to design schemes of land exploitation and urban development in mountainous areas.In this study,the teaching-learning-based optimization(TLBO)and satin bowerbird optimizer(SBO)algorithms were applied to optimize the adaptive neuro-fuzzy inference system(ANFIS)model for landslide susceptibility mapping.In the study area,152 landslides were identified and randomly divided into two groups as training(70%)and validation(30%)dataset.Additionally,a total of fifteen landslide influencing factors were selected.The relative importance and weights of various influencing factors were determined using the step-wise weight assessment ratio analysis(SWARA)method.Finally,the comprehensive performance of the two models was validated and compared using various indexes,such as the root mean square error(RMSE),processing time,convergence,and area under receiver operating characteristic curves(AUROC).The results demonstrated that the AUROC values of the ANFIS,ANFIS-TLBO and ANFIS-SBO models with the training data were 0.808,0.785 and 0.755,respectively.In terms of the validation dataset,the ANFISSBO model exhibited a higher AUROC value of 0.781,while the AUROC value of the ANFIS-TLBO and ANFIS models were 0.749 and 0.681,respectively.Moreover,the ANFIS-SBO model showed lower RMSE values for the validation dataset,indicating that the SBO algorithm had a better optimization capability.Meanwhile,the processing time and convergence of the ANFIS-SBO model were far superior to those of the ANFIS-TLBO model.Therefore,both the ensemble models proposed in this paper can generate adequate results,and the ANFIS-SBO model is recommended as the more suitable model for landslide susceptibility assessment in the study area considered due to its excellent accuracy and efficiency.
文摘The purpose of this paper is to advance the interpretation of the Du Pont Equation, which is commonly used in the financial statements analysis of corporations. The paper makes a special interpretation of the three terms which appear in the Du Pont Equation that provides an understanding of the overall financial standing of the corporation under consideration. As a result of this interpretation, the order in which f'mancial statements analysis is commonly performed should be reversed. That is, in financial statements analysis, one should start with the analysis of the Du Pont Equation, to gain an overall understanding of the financial situation of the corporation; and then, perform the ratio analysis, to gain a detailed understanding of the financial situation of the corporation. This order of analysis is in contrast to the order in which financial statements analysis is commonly performed, i.e., first, the ratio analysis is performed, and then, the Du Pont Equation is analyzed.
文摘Optimization of capital structure has been a famous issue in Corporate Finance.It is essential for modern companies to find the optional capital structure of themselves because it could help these companies to reduce the cost of finance.This best structure is not easy to find out due to the complex determinants behind it.However,there still are some alternative ways could be used to judge whether a company reach its optional capital structure.This report takes X company as an example to discuss that how to use different efficient methods to estimate the optional capital structure of a company.
基金Indian Institute of Technology,Kharagpur in India for supporting this work
文摘Particle size distribution of coarse aggregates through mechanical sieving gives results in terms of cumu- lative mass percent. But digital image processing generated size distribution of particles, while being fast and accurate, is often expressed in terms of area function or number of particles. In this paper, a mass model is developed which converts the image obtained size distribution to mass-wise distribution, mak- ing it readily comparable to mechanical sieving data. The concept of weight/particle ratio is introduced for mass reconstruction from 2D images of particle aggregates. Using this mass model, the effects of several particle shape parameters (such as major axis, minor axis, and equivalent diameter) on sieve-size of the particles is studied. It is shown that the sieve-size of a particle strongly depend upon the shape param- eters, 91% of its variation being explained by major axis, minor axis, bounding box length and equivalent diameter. Furthermore, minor axis gives an overall accurate estimate of particle sieve-size, error in mean size (D-50) being just 0.4%. However, sieve-size of smaller particles (〈20 ram) strongly depends upon the length of the smaller arm of the bounding box enclosing them and sieve-sizes of larger particles (〉20 mm) are highly correlated to their equivalent diameters. Multiple linear regression analysis has been used to generate overall mass-wise particle size distribution, considering the influences of all these shape parameters on particle sieve-size. Multiple linear regression generated overall mass-wise particle size distribution shows a strong correlation with sieve generated data. The adjusted R-square value of the regression analysis is found to be 99 percent (w.r,t cumulative frequency). The method proposed in this paper provides a time-efficient way of producing accurate (up to 99%) mass-wise PSD using digital image processing and it can be used effectively to renlace the mechanical sieving.
基金supported by the by the Ministerio de Economía y Competitividad under project FIS2012-31079
文摘Several pupil filtering techniques have been developed in the last few years to obtain transverse superresolution (a narrower point spread function core). Such a core decrease entails two relevant limitations: a decrease of the peak intensity and an increase of the sidelobe intensity. Here, we calculate the Strehl ratio as a function of the core size for the most used binary phase filters. Furthermore, we show that this relation approaches the fundamental limit of the attainable Strehl ratio at the focal plane for any filter. Finally, we show the calculation of the peak-to-sidelobe ratio in order to check the system viability in every application.
文摘A new simple spectrophotometric method was developed for the determination of binary mixtures without prior separation.The method is based on the generation of ratio spectra of compound X by using a standard spectrum of compound Y as a divisor.The peak to trough amplitudes between two selected wavelengths in the ratio spectra are proportional to concentration of X without interference from Y.The method was demonstrated by determination of two drug combinations.The first consists of the two antihyperlipidemics:atorvastatin calcium(ATV) and ezetimibe(EZE),and the second comprises the antihypertensives:candesartan cilexetil(CAN) and hydrochlorothiazide(HCT).For mixture 1,ATV was determined using 10 μg/mL EZE as the divisor to generate the ratio spectra,and the peak to trough amplitudes between 231 and 276 nm were plotted against ATV concentration.Similarly,by using 10 μg/mL ATV as divisor,the peak to trough amplitudes between 231 and 276 nm were found proportional to EZE concentration.Calibration curves were linear in the range 2.5-40 mg/mL for both drugs.For mixture 2,divisor concentration was 7.5 μg/mL for both drugs.CAN was determined using its peak to trough amplitudes at 251 and 277 nm,while HCT was estimated using the amplitudes between 251 and 276 nm.The measured amplitudes were linearly correlated to concentration in the ranges 2.5-50 and 1-30 μg/mL for CAN and HCT,respectively.The proposed spectrophotometric method was validated and successfully applied for the assay of both drug combinations in several laboratory-prepared mixtures and commercial tablets.
文摘Since it is a gradual process for listed companies to plunge into financial failure, it is desirable to discern tho potential risks in advance. This paper, with the adoption of multiple discriminant analyzing approach, tries to find out optimal variables and financial failure predicting model for Chinese listed companies based on audited accounting data.
基金supported by the 10th National Five-Year Program for Science and Technology Development of China(Grant No.2003BA614A-02)
文摘The process of economic activities is on the basis of tremendous material inputs.China has been discharging an enormous amount of waste,giving rise to a wide range of environmental impacts.The method of economy-wide material flow analysis(EW-MFA)is one of the effective tools to examine the flow of materials entering physical economies,and recognize early environmental problems.Relevant researches are still at the early stage in China and most focus on material throughput but are rarely concerned about the utilization of recycling resource and environmental impact.Based on more than 3,000 items of data related,materials entering Chinese economy are classified into three types,and then the characteristics of material input and environmental impact are presented for the years 1990-2005 by using the indicators derived from EW-MFA.The Ratio of Recycled Material(RRM) is added as the new indicator in order to be in accordance with the need of circular economy being promoted in China.Results show that the great changes in the structure of material input cause the continuous increase of industrial solid waste emissions and the bogging down of material productivity.The RRM reveals that the utilization of recycling resources remains at a fairly low level in China.Finally,some weakness of EW-MFA is discussed according to the calculated results.
文摘Background: Tertiary hospitals serve as the medical service center within the region and play an important role in the medical and health service system. They are also the key targets of public hospital reform in the new era in China. Through the reform of health system, the public hospital efficiency has changed remarkably. Therefore, this study aimed to provide some advice for efficiency assessment of public hospitals in China by comparing and analyzing the consistency of results obtained by three commonly used methods for examining hospital efficiency, that is, ratio analysis (RA), stochastic frontier analysis (SFA), and data envelopment analysis (DEA). Methods: The theoretical basis, operational processes, and the application status of RA, SFA, and DEA were learned through literature analysis. Then, the empirical analysis was conducted based on measured data from 51 tertiary public hospitals in Beijing from 2009 to 2011. Results: The average values of hospital efficiency calculated by SFA with index screening and principal component analysis (PCA) results and those calculated by DEA with index screening results were relatively stable. The efficiency of specialized hospitals was higher than that of general hospitals and that of traditional Chinese medicine hospitals. The results obtained by SFA with index screening results and the results obtained by S FA with PCA results showed a relatively high correlation (r-value in 2009, 2010, and 2011 were 0.869, 0.753, and 0.842, respectively, P 〈 0.01). The correlation between results obtained by DEA with index screening results and PCA results and results obtained by other methods showed statistical significance, but the correlation between results obtained by DEA with index screening results and PCA results was lower than that between results obtained by SFA with index screening results and PCA results. Conclusions: RA is not suitable for multi-index evaluation of hospital efficiency. In the given conditions, SFA is a stable efficiency analysis method. In the evaluation of hospital efficiency, DEA combined with PCA should be adopted with caution due to its poor stability.
文摘Background Lymph node ratio (LNR) has recently been reported as a potential prognostic marker in many malignant diseases. We aimed to analyze the potential prognostic effect of LNR on hypopharyngeal squamous cell carcinoma (HPSCC) after neoadjuvant therapy in our institution.
基金supported in part by the National Science Foundation under Grant CNS-1248079 and CNS-1135844.
文摘The problem of large-scale charging of electric vehicles(EVs)with consumer-imposed charging deadlines is considered.An architecture for the intelligent energy management system(iEMS)is introduced.The iEMS consists of an admission control and pricing module,a scheduling module that determines the charging sequence,and a power dispatch module that draws power from a mix of storage,local renewable energy sources,and purchased power from the grid.A threshold admission and greedy scheduling(TAGS)policy is proposed to maximize operation profit.The performance of TAGS is analyzed and evaluated based on average and worst-case performance measures and the optimality of TAGS is established for some instances.Numerical simulations demonstrate that TAGS achieves noticeable performance gains over benchmark techniques.
基金supported by the National Natural Science Foundation of China (No. 20877093, 51278355)
文摘The strategy of choosing suitable plants should receive great performance in phytoremediation of surface water polluted by triazophos (O,O-diethyl-O-(1-phenyl- 1,2,4-triazol-3-base) sulfur phosphate, TAP), which is an organophosphorus pesticide widespread applied for agriculture in China and moderately toxic to higher animal and fish. The tolerance, uptake, transformation and removal of TAP by twelve species of macrophytes were examined in a hydroponic system and a comprehensive score (CS) of five parameters (relative growth rate (RGR), biomass, root/shoot ratio, removal capacity (RC), and bio-concentration factor (BCF)) by factor analysis was employed to screen the potential macrophyte species for TAP phytoremediation. The results showed that Thalia dealbata, Cyperus alternifolius, Canna indica and Acorus calamus had higher RGR values, indicating these four species having stronger growth capacity under TAP stress. The higher RC loading in Iris pseudacorus and Cyperus rotundus were 42.11 and 24.63μg/(g fw.day), respectively. The highest values of BCF occurred in A. calamus (1.17), and TF occurred in Eichhornia crassipes (2.14). Biomass and root/shoot ratio of plant showed significant positive correlation with first-order kinetic constant of TAP removal in the hydroponic system, indicating that plant biomass and root system play important roles in remediation of TAP. Five plant species including C. alternifolius, A. calamus, T. dealbata, C. indica and Typha orientalis, which owned higher CS, would be potential species for TAP phytoremediation of contaminated water bodies.