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The Prediction for the Consumer Price Index of Residents in Perspective of Time Series Method in Case of Chongqing
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作者 Chunhuan Xiang 《Journal of Applied Mathematics and Physics》 2024年第1期226-233,共8页
The consumer price index (CPI) measures the relative number of changes in the price level of consumer goods and services over time, reflecting the trend and degree of changes in the price level of goods and services p... The consumer price index (CPI) measures the relative number of changes in the price level of consumer goods and services over time, reflecting the trend and degree of changes in the price level of goods and services purchased by residents. This article uses the ARMA model to analyze the fluctuation trend of the CPI (taking Chongqing as an example) and make short-term predictions. To test the predictive performance of the model, the observation values from January to December 2023 were retained as the reference object for evaluating the predictive accuracy of the model. Finally, through trial predictions of the data from May to August 2023, it was found that the constructed model had good fitting performance. 展开更多
关键词 Consumer price index of Residents PREDICTIon ARMA Model
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How can technology and efficiency alleviate the dilemma of economic growth and carbon emissions in China's industrial economy? A metafrontier decoupling decomposition analysis
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作者 Miao Wang Chao Feng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1415-1428,共14页
This paper attempts to explore the decoupling relationship and its drivers between industrial economic increase and energy-related CO_(2) emissions(ICE). Firstly, the decoupling relationship was evaluated by Tapio ind... This paper attempts to explore the decoupling relationship and its drivers between industrial economic increase and energy-related CO_(2) emissions(ICE). Firstly, the decoupling relationship was evaluated by Tapio index. Then, based on the DEA meta-frontier theory framework which taking into account the regional and industrial heterogeneity and index decomposition method, the driving factors of decoupling process were explored mainly from the view of technology and efficiency. The results show that during2000-2019, weak decoupling was the primary state. Investment scale expansion was the largest reason hindering decoupling process of industrial increase from ICE. Both energy saving and production technology achieved significant progress, which facilitated the decoupling process. Simultaneously, the energy technology gap and production technology gap among regions have been narrowed, and played a role in promoting decoupling process. On the contrary, both scale economy efficiency and pure technical efficiency have inhibiting effects on decoupling process. The former indicates that the scale economy of China's industry was not conducive to improve energy efficiency and production efficiency, while the latter indicates that resource misallocation problem may exist in both energy market and product market. 展开更多
关键词 China's industrial sector Decoupling process Meta-frontier DEA index decomposition method Driving factors
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Production Chain Length and PPI-CPI Divergence:Analysis Based on the Global Input-output Price Model
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作者 Ni Hongfu Yan Bingqian Wu Liyuan 《China Economist》 2024年第3期49-69,共21页
Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production ... Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production chains.The question is how the changing length of production chains will affect CPI and PPI,as well as CPI-PPI correlation?By constructing a global input-output price model,this paper offers a theoretical discussion on the impact of production chain length on the CPI-PPI divergence.Our findings suggest that the price shock of international bulk commodities has a greater impact on China’s PPI than that on CPI.The effects on both China’s PPI and CPI estimated by using the single-country input-output model are higher than the results estimated with the global input-output model.However,the difference between CPI and PPI variations estimated with the global input-output model is greater than the result estimated with the single-country input-output model,which supports the view that the lengthening of production chains,especially international production chains,leads to a divergence between CPI and PPI.Empirical results based on cross-national panel data also suggest that the lengthening of production chains has reduced the CPI-PPI correlation for countries,i.e.the lengthening of production chains has increased the PPI-CPI divergence.That is to say,policymakers should target not just CPI in maintaining price stability,but instead focus on the stability of both PPI and CPI.Efforts can be made to proactively adjust the price index system,and formulate the industrial chain price index. 展开更多
关键词 Global value chains length of production chains consumer price index producer price index
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Numerical investigation of the effects of soil-structure and granular material-structure interaction on the seismic response of a flat-bottom reinforced concrete silo
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作者 Sonia Benkhellat Mohammed Kadri Abdelghani Seghir 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期609-623,共15页
In this work,a numerical study of the effects of soil-structure interaction(SSI)and granular material-structure interaction(GSI)on the nonlinear response and seismic capacity of flat-bottomed storage silos is conducte... In this work,a numerical study of the effects of soil-structure interaction(SSI)and granular material-structure interaction(GSI)on the nonlinear response and seismic capacity of flat-bottomed storage silos is conducted.A series of incremental dynamic analyses(IDA)are performed on a case of large reinforced concrete silo using 10 seismic recordings.The IDA results are given by two average IDA capacity curves,which are represented,as well as the seismic capacity of the studied structure,with and without a consideration of the SSI while accounting for the effect of GSI.These curves are used to quantify and evaluate the damage of the studied silo by utilizing two damage indices,one based on dissipated energy and the other on displacement and dissipated energy.The cumulative energy dissipation curves obtained by the average IDA capacity curves with and without SSI are presented as a function of the base shear,and these curves allow one to obtain the two critical points and the different limit states of the structure.It is observed that the SSI and GSI significantly influence the seismic response and capacity of the studied structure,particularly at higher levels of PGA.Moreover,the effect of the SSI reduces the damage index of the studied structure by 4%. 展开更多
关键词 reinforced concrete silo perfectly matched layers soil-structure interaction granular material-structure interaction effective seismic input method damage index
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Clinical Study on the Treatment of Low Anal Fistula in Infants and Young Children by Anal Gland Excision and Virtual Hanging Procedure
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作者 Hongbo Su Linmei Sun +5 位作者 Yimiao Liang Jiansheng Hu Yongli Zhang Ni Wei Chaoyang Li Lin Tang 《Journal of Clinical and Nursing Research》 2024年第3期18-25,共8页
Objective:To compare the efficacy of anal adenectomy with virtual hanging wire and anal fistulotomy in the treatment of low anal fistula in infants and children.Methods:60 children with low anal fistula who were admit... Objective:To compare the efficacy of anal adenectomy with virtual hanging wire and anal fistulotomy in the treatment of low anal fistula in infants and children.Methods:60 children with low anal fistula who were admitted to our hospital from October 2021 to March 2022 and met the inclusion criteria were randomly divided into two groups of 30 cases each;the treatment group was treated with anal adenectomy and virtual hanging wire surgery,and the control group was treated with anal fistula resection.The clinical efficacy after treatment was compared.Results:The total effective rate of both groups was 96.67%and the difference between the two groups was not statistically significant(P>0.05).The postoperative pain score of the treatment group was lower than that of the control group(P<0.05).The length of hospitalization and healing time of the treatment group was lower than that of the control group(P<0.05).The anal function of the patients in both groups was normal,and there was no adverse reaction.Conclusion:Anal gland excision and virtual hanging surgery for the treatment of low anal fistula in infants and children have the advantages of mild pain,reduced length of hospitalization,short healing time,and better patient experience as compared to anal fistula excision. 展开更多
关键词 Anal fistula Anal gland excision Virtual hanging procedure Surgical method Observation index Clinical efficacy
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Is pass‑through of the exchange rate to restaurant and hotel prices asymmetric in the US?Role of monetary policy uncertainty
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作者 Uju Violet Alola Ojonugwa Usman Andrew Adewale Alola 《Financial Innovation》 2023年第1期539-557,共19页
This study examines the exchange rate pass-through to the United States(US)restaurant and hotel prices by incorporating the effect of monetary policy uncertainty over the period 2001:M12 to 2019:M01.Using the nonlinea... This study examines the exchange rate pass-through to the United States(US)restaurant and hotel prices by incorporating the effect of monetary policy uncertainty over the period 2001:M12 to 2019:M01.Using the nonlinear autoregressive distributed lag(NARDL)model,empirical evidence indicates asymmetric pass-through of exchange rate and monetary policy uncertainty.Moreover,a stronger pass-through effect is observed during depreciation and a negative shock in monetary policy uncertainty,corroborating asymmetric pass-through predictions.Our results further show that a positive shock in energy prices leads to an increase in restaurant and hotel prices.Furthermore,asymmetric causality indicates that a positive shock in the exchange rate causes a positive shock to restaurant and hotel prices.We found feedback causal effects between positive and negative shocks in monetary policy uncertainty and positive and negative shocks in the exchange rate.Additionally,we detected a one-way asymmetric causality,flowing from a positive(negative)shock to a positive(negative)shock in energy prices.Therefore,these findings provide insights for policymakers to achieve low and stable prices in the US restaurant and hotel industry through sound monetary policy formulations.Highlights.The drivers of restaurant and hotel business in tourism destinations are examined.There is asymmetric pass-through of exchange rate and monetary policy uncertainty.A stronger pass-through is observed during appreciation and a negative shock to monetary policy uncertainty.There is asymmetric causality from positive shock in exchange rate to postive shock in restaurant and hotel prices. 展开更多
关键词 Restaurant and hotel prices Exchange rate Monetary policy uncertainty Energy price index US economy
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Do U.S.economic conditions at the state level predict the realized volatility of oil‑price returns?A quantile machine‑learning approach
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作者 Rangan Gupta Christian Pierdzioch 《Financial Innovation》 2023年第1期645-666,共22页
Because the U.S.is a major player in the international oil market,it is interesting to study whether aggregate and state-level economic conditions can predict the subse-quent realized volatility of oil price returns.T... Because the U.S.is a major player in the international oil market,it is interesting to study whether aggregate and state-level economic conditions can predict the subse-quent realized volatility of oil price returns.To address this research question,we frame our analysis in terms of variants of the popular heterogeneous autoregressive realized volatility(HAR-RV)model.To estimate the models,we use quantile-regression and quantile machine learning(Lasso)estimators.Our estimation results highlights the dif-ferential effects of economic conditions on the quantiles of the conditional distribution of realized volatility.Using weekly data for the period April 1987 to December 2021,we document evidence of predictability at a biweekly and monthly horizon. 展开更多
关键词 Oil price Realized volatility Economic conditions indexes Quantile Lasso Prediction models
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AI-Enhanced Performance Evaluation of Python, MATLAB, and Scilab for Solving Nonlinear Systems of Equations: A Comparative Study Using the Broyden Method
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作者 Isaac Azure Japheth Kodua Wiredu +1 位作者 Anas Musah Eric Akolgo 《American Journal of Computational Mathematics》 2023年第4期644-677,共34页
This research extensively evaluates three leading mathematical software packages: Python, MATLAB, and Scilab, in the context of solving nonlinear systems of equations with five unknown variables. The study’s core obj... This research extensively evaluates three leading mathematical software packages: Python, MATLAB, and Scilab, in the context of solving nonlinear systems of equations with five unknown variables. The study’s core objectives include comparing software performance using standardized benchmarks, employing key performance metrics for quantitative assessment, and examining the influence of varying hardware specifications on software efficiency across HP ProBook, HP EliteBook, Dell Inspiron, and Dell Latitude laptops. Results from this investigation reveal insights into the capabilities of these software tools in diverse computing environments. On the HP ProBook, Python consistently outperforms MATLAB in terms of computational time. Python also exhibits a lower robustness index for problems 3 and 5 but matches or surpasses MATLAB for problem 1, for some initial guess values. In contrast, on the HP EliteBook, MATLAB consistently exhibits shorter computational times than Python across all benchmark problems. However, Python maintains a lower robustness index for most problems, except for problem 3, where MATLAB performs better. A notable challenge is Python’s failure to converge for problem 4 with certain initial guess values, while MATLAB succeeds in producing results. Analysis on the Dell Inspiron reveals a split in strengths. Python demonstrates superior computational efficiency for some problems, while MATLAB excels in handling others. This pattern extends to the robustness index, with Python showing lower values for some problems, and MATLAB achieving the lowest indices for other problems. In conclusion, this research offers valuable insights into the comparative performance of Python, MATLAB, and Scilab in solving nonlinear systems of equations. It underscores the importance of considering both software and hardware specifications in real-world applications. The choice between Python and MATLAB can yield distinct advantages depending on the specific problem and computational environment, providing guidance for researchers and practitioners in selecting tools for their unique challenges. 展开更多
关键词 System of Nonlinear Equations Broyden method Robustness index Artificial Intelligence (AI) MATLAB SCILAB PYTHon
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Construction of the First Certification Evaluation Index System for Diabetes Specialist Nurses by Delphi Method 被引量:4
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作者 Haihua Zou Xue Gong +1 位作者 Siyun Wang Weiju Chen 《International Journal of Clinical Medicine》 2020年第5期242-251,共10页
Objective: To establish an evaluation index system for the first-time certification of diabetes specialist nurses in line with the clinical nursing practice in China, and to provide a reference basis for government ad... Objective: To establish an evaluation index system for the first-time certification of diabetes specialist nurses in line with the clinical nursing practice in China, and to provide a reference basis for government administrations and hospitals to formulate unified standards. Methods: After the research team has determined the theme, it will consult the development of A) specialist nursing through the library, Internet and electronic literature database;B) the history of the development of specialist nurses in diabetes and other fields;C) the selection criteria of specialist nurses;D) the training of specialist nurses system, assessment method;E) Specialist nurse certification body, evaluation standards and certification standards and other related documents, literature, books and report materials. The author established the preliminary index system through literature review, specialist interview and group discussion and used Delphi method to organize three rounds of 30 experts’ consultations. Results: A first certification evaluation index system including 8 fundamental indicators, 5 first-level indicators, 19 second-level indicators and 99 third-level indicators was constructed for diabetes nurses. Conclusion: The results of three rounds of expert consultation and demonstration are reliable, and the constructed index system is suitable for comprehensive evaluation of diabetes specialist nurses, which provides a basis for the effective management of nursing resources. 展开更多
关键词 DIABETIC SPECIALIST Nurses First CERTIFICATIon Evaluation index DELPHI method
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The study of coal mine equipment’s comprehensive evaluation index system and evaluation method 被引量:2
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作者 王新华 史国庆 《Journal of Coal Science & Engineering(China)》 2004年第2期117-121,共5页
Equipment management is one of the important parts of business administra- tion of coal. Most of coal mines take no account of their equipment management, and have no comprehensive and effective evaluation index syste... Equipment management is one of the important parts of business administra- tion of coal. Most of coal mines take no account of their equipment management, and have no comprehensive and effective evaluation index system. Based on the analysis of the equipment evaluation measures of reform and the applications, the paper built up a comprehensive and effective evaluation index system of coal mine equipment, and im- proved the evaluation method with the use of fuzzy theory, analytic hierarchy process and entropy method. 展开更多
关键词 equipment of coal mine comprehensive evaluation index system fuzzy theory entropy method
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The Empirical Analysis of the Relationship between our Country Steel Price Index and the International Iron ore Freight Rate
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作者 陈佳娜 朱意秋 《海外英语》 2012年第9X期286-288,共3页
The use of econometric methods to analyze the relationship between our country steel price index and the international iron ore freight rate,time series stationarity test,cointegration test,Granger test of causality a... The use of econometric methods to analyze the relationship between our country steel price index and the international iron ore freight rate,time series stationarity test,cointegration test,Granger test of causality and model parameter estimation tools use,find that there is Granger causality between our country steel price index and the international iron ore freight rate,China' s steel price fluctuations to some extent affect the international iron ore freight. 展开更多
关键词 China factors STEEL price index iron ORE FREIGHT r
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Research on the statistics index system and evaluation method of high and new technology industry development
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作者 李晓东 张霞 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第3期334-337,共4页
During the evolution of the global economic, high and new technology industry has become the main driver to impel the global economy growth via technological advancement, and the main means to guarantee the sustainabl... During the evolution of the global economic, high and new technology industry has become the main driver to impel the global economy growth via technological advancement, and the main means to guarantee the sustainable development of the global economy. In the view of China’s situation, this article analyzes the experiences of OECD in high and new technology industry and gives a statistics index system along with the evaluation method to estimate the development of high and new technology industry. 展开更多
关键词 High and new technology industry DEVELOPMENT Statistics index system Evaluation method
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A new estimation method and an anisotropy index for the deformation modulus of jointed rock masses
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作者 Bohu Zhang Junyan Mu +2 位作者 Jun Zheng Qing Lv Jianhui Deng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第1期153-168,共16页
The deformation modulus of a rock mass is an important parameter to describe its mechanical behavior.In this study,an analytical method is developed to determine the deformation modulus of jointed rock masses,which co... The deformation modulus of a rock mass is an important parameter to describe its mechanical behavior.In this study,an analytical method is developed to determine the deformation modulus of jointed rock masses,which considers the mechanical properties of intact rocks and joints based on the superposition principle.Due to incorporating the variations in the orientations and sizes of joint sets,the proposed method is applicable to the rock mass with persistent and parallel joints as well as that with nonpersistent and nonparallel joints.In addition,an anisotropy index AIdmfor the deformation modulus is defined to quantitatively describe the anisotropy of rock masses.The range of AIdmis from 0 to 1,and the more anisotropic the rock mass is,the larger the value of AIdmwill be.To evaluate the proposed method,20 groups of numerical experiments are conducted with the universal distinct element code(UDEC).For each experimental group,the deformation modulus in 24 directions are obtained by UDEC(numerical value)and the proposed method(predicted value),and then the mean error rates are calculated.Note that the mean error rate is the mean value of the error rates of the deformation modulus in 24 directions,where for each direction,the error rate is equal to the ratio of numerical value minus predicted value to the numerical value.The results show that(i)for different experimental groups,the mean error rates vary between 5.06%and 22.03%;(ii)the error rates for the discrete fracture networks(DFNs)with two sets of joints are at the same level as those with one set of joints;and(iii)therefore,the proposed method for estimating the deformation modulus of jointed rock masses is valid. 展开更多
关键词 Deformation modulus Analytical method Anisotropy index Jointed rock masses Mechanical behavior Discrete fracture network(DFN)
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The Changes in World Oil Prices, Monetary Factors, and Foreign Index Toward Composite Index Movement: Indonesian Case for the Period of 2005-2011
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作者 Darmawan Achmad Ishak Ramli 《Journal of Modern Accounting and Auditing》 2013年第9期1263-1274,共12页
Capital market is one of the drivers of the economy through the formation of capital investor excess as well as an indicator of a country's economy. Movement of stock price index is often influenced by many factors, ... Capital market is one of the drivers of the economy through the formation of capital investor excess as well as an indicator of a country's economy. Movement of stock price index is often influenced by many factors, derived from the company's performance, monetary factor, and changes in world oil prices. This study highlights the problem in world oil prices due to political turmoil in the Middle East. The samples are taken from the Jakarta Composite Stock Price Index (JCI), oil prices, Indonesian inflation rate, Certificate of Bank Indonesia's (CBI) rate, and the reserve assets, during the period from January 2005 to December 2011 (84 months). Using the data published by the Bank of Indonesia, reports of the Central Bureau of Statistics (Biro Pusat Statistik, BPS), and other relevant sources, the data analyzed through the Eviews 7.1. The main objective of this study is to examine the effect of oil prices, foreign stock price index, and monetary variables (inflation rate, CBI rate, country's foreign reserves, and others) toward the JCI analyzed through the error correction model (ECM). Hypothesis testing with the F-test for the 95% confidence level indicates that the oil price, exchange rate (Indonesian Rupiah (IDR)/United States Dollar (USD)), CBI rate, foreign exchange reserves, the Dow Jones Index, and the Taiwan stock index, both simultaneously as well as partially have a significant influence on the JCI. 展开更多
关键词 Jakarta Composite Stock price index (1CI) world oil prices country's foreign reserves IndonesianRupiah (IDR) foreign stock prices
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Research on the Change of GDP Growth,Monetary Growth and Price Index based on VAR and IRF
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作者 Jifeng Sun Tingna Sun 《Journal of Management Science & Engineering Research》 2020年第1期11-16,共6页
In this paper,we use the macro data from the first quarter of 2001 to the first quarter of 2015,through vector autoregressive(VAR)model,Granger causality analysis,impulse response function(RFI)and variance decompositi... In this paper,we use the macro data from the first quarter of 2001 to the first quarter of 2015,through vector autoregressive(VAR)model,Granger causality analysis,impulse response function(RFI)and variance decomposition analysis of quantitative analysis methods,to research on the relationship among China’s real growth variation of gross domestic product(GDP),Money supply growth rate and consumer price index.We find that the money supply growth has impact on China’s real growth variation of GDP in short-term,but there is no long-term significant effect.Economic growth is the main factor to promote the consumer price index growth,money growth is not the main factor driving the change in the price index.China’s currency growth is affected significantly by the change of the economic growth. 展开更多
关键词 GDP growth variation Broad money growth rate Consumer price index
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Study on the evaluation index system and evaluation method for self-elevating drilling unit design 被引量:1
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作者 王运龙 纪卓尚 《Journal of Marine Science and Application》 2009年第1期46-52,共7页
In the process of designing self-elevating drilling unit, it is important, yet complicated, to use comparison and filtering to select the optimum scheme from the feasible ones. In this research, an index system and me... In the process of designing self-elevating drilling unit, it is important, yet complicated, to use comparison and filtering to select the optimum scheme from the feasible ones. In this research, an index system and methodology for the evaluation of self-elevating drilling unit was proposed. Based on this, a multi-objective combinatorial optimization model was developed, using the improved grey relation Analysis (GRA), in which the analytic hierarchy process (AHP) was used to determine the weights of the evaluating indices. It considered the connections within the indices, reflecting the objective nature of things, and also considered the subjective interests of ship owners and the needs of designers. The evaluation index system and evaluation method can be used in the selection of an optimal scheme and advanced assessment. A case study shows the index system and evaluation method are scientific, reasonable, and easy to put into practice. At the same time, such an evaluation index system and evaluation method will be helpful for making decisions for other mobile platforms. 展开更多
关键词 self-elevating drilling unit evaluation index system evaluation method grey relation analysis (GRA) analytic hierarchy process (AHP)
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The Response of Consumer Food Price Index(CFPI)due to the Impact of Pandemic COVID-19 on Indian Agriculture Sector
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作者 Digvijay Pandey Nidhi Verma +3 位作者 Tajamul Islam Wegayehu Enbeyle Binay Kumar Pandey PMadhusudana Patra 《NASS Journal of Agricultural Sciences》 2021年第1期29-35,共7页
India is an agricultural country and a core source of income for the world population.The Indian economy is greatly depending on agriculture that is decrease day by day due to pandemic COVID-19.India is a major export... India is an agricultural country and a core source of income for the world population.The Indian economy is greatly depending on agriculture that is decrease day by day due to pandemic COVID-19.India is a major exporter of many crop foods.India,Thailand,and Vietnam are the major exports of rice if these stopped exports it reduces the economy up to 15%.A related circumstance is built up with diverse yields too like wheat,sunflower whose fare has been stationary by Kazakhstan,Serbia individually.In India,the end of April is the main source of income to farmers because they sell their rabi crops(wheat,mustard,maize,lentil,chilies,gram,tomatoes)in the market drastically decreases of CFPI may lead to the distress of Indian agricultural economy.The change over time in the price of options on wheat futures reveals increased price volatility in response to growing uncertainty about the COVID-19 impacts. 展开更多
关键词 CORonAVIRUS COVID-19 2019-nCoV PANDEMIC Public health emergency Middle-Eastern-Respiratory Syndrome(MERS) Consumer food price index(CFPI)
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Dynamic response of buildings under debris flow impact
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作者 LIU Huan FAN Xiaoyi +1 位作者 TIAN Shujun DENG Xin 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1581-1597,共17页
This study employs the smoothed particle hydrodynamics–finite element method(SPH–FEM) coupling numerical method to investigate the impact of debris flow on reinforced concrete(RC)-frame buildings. The methodology co... This study employs the smoothed particle hydrodynamics–finite element method(SPH–FEM) coupling numerical method to investigate the impact of debris flow on reinforced concrete(RC)-frame buildings. The methodology considers the variables of debris flow depth and velocity and introduces the intensity index IDV(IDV = DV) to evaluate three different levels of debris flow impact intensity. The primary focus of this study is to investigate the dynamic response and failure mechanism of RC-frame buildings under debris flow impact, including structural failure patterns, impact force and column displacement. The results show that under a highintensity impact, a gradual collapse process of the RCframe building can be observed, and the damage mode of the frame column reflects shear failure or plastic hinge failure mechanism. First, the longitudinal infill walls are damaged owing to their low out-of-plane flexural capacity;the critical failure intensity index IDV value is approximately 7.5 m2/s. The structure cannot withstand debris flows with an intensity index IDV greater than 16 m2/s, and it is recommended that the peak impact force should not exceed 2100 k N. The impact damage ability of debris flow on buildings mostly originates from the impact force of the frontal debris flow, with the impact force of the debris flow body being approximately 42% lower than that of the debris flow head. Finally, a five-level classification system for evaluating the damage status of buildings is proposed based on the numerical simulation and investigation results of the disaster site. 展开更多
关键词 SPH–FEM method Debris flow BUILDINGS the intensity index Dynamic response
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Integrated Analysis of Water Quality in Artificial Fishponds Using WQI and GIS in South-East Sierra Leone
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作者 Hadji D. S. Kallon Lamin R. Mansaray +1 位作者 Misbah Fida Pratap Sundar Shrestha 《Journal of Geoscience and Environment Protection》 2024年第1期145-163,共19页
Artificial fishponds play a pivotal role in global aquaculture, serving as a source of livelihood and nourishment for many communities. Ensuring the sustained health and productivity of Fishes in these environments re... Artificial fishponds play a pivotal role in global aquaculture, serving as a source of livelihood and nourishment for many communities. Ensuring the sustained health and productivity of Fishes in these environments relies heavily on water quality management. This assessment was done to determine the water quality of ten artificial fishponds in the south-eastern part of Sierra Leone using twelve physicochemical factors (pH, BOD, EC, TDS, turbidity, COD, Fe<sup>2+</sup>, Mg<sup>2+</sup>, Ca<sup>2+</sup>, NH<sub>3</sub>, , and alkalinity) to find out the Water Quality Index (WQI) and spatial distribution of respective parameters. The assessment of artificial fishponds using WQI and Inverse Distant Weighting (IDW) integration represents a relatively underexplored area within the domain of environmental water resources. The WQI was determined using the “Weighted Arithmetic Water Quality Index’’ method. The results of WQI in the study area range from 65.05 to 147.26. Several locations have water quality deemed unsuitable for consumption, while others range from good to very poor. It is essential to address and improve water quality in locations categorized as unsuitable for consumption and very poor to ensure safe and healthy water sources. It was also clear from the calculation that the smaller the mean concentration value of the pH as compared to the ideal value (7), the smaller the WQI value and the better the water quality. To keep the artificial fishpond water in good condition, mass domestic use should be controlled, and draining of surrounding organic matter should be stopped in ponds Bo_001, Kenema_001, and Kenema_002. 展开更多
关键词 Physicochemical Parameters Water Quality index WQI-“Weighted Arithmetic index method
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Stability Analysis of Nonlinear Models of Nose Landing Gear Shimmy
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作者 Jiacai Zhou Yanying Zhao +1 位作者 Qiqi Li Longhua Zhou 《World Journal of Engineering and Technology》 2024年第1期103-116,共14页
Shimmy can reduce the service life of the nose landing gear, affect ride comfort, and even cause fuselage damage leading to aircraft crashes. Taking a light aircraft as the research object, the torsional freedom of la... Shimmy can reduce the service life of the nose landing gear, affect ride comfort, and even cause fuselage damage leading to aircraft crashes. Taking a light aircraft as the research object, the torsional freedom of landing gear around strut axis and lateral deformation of tire are considered. Since the landing gear shimmy is a nonlinear system, a nonlinear mechanical model of the front landing gear shimmy is established. Sobol index method is proposed to analyze the influence of structural parameters on the stability region of the nose landing gear, and Routh-Huritz criterion is used to verify the reliability of the analysis results of Sobol index method. We analyse the effect of torsional stiffness of strut, caster length, rated initial tire inflation pressure, rake angle, and vertical force on the stability region of theront landing gear. And the research shows that the optimization of the torsional stiffness of the strut and the caster length of the nose landing gear should be emphasized, and the influence of vertical force on the stability region of the nose landing gear should be paid attention to. 展开更多
关键词 Nose Landing Gear Shimmy Oscillations STABILITY Sobol index method
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