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New robust chaotic system with exponential quadratic term 被引量:9
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作者 包伯成 李春彪 +1 位作者 许建平 刘中 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第11期4022-4026,共5页
This paper proposes a new robust chaotic system of three-dimensional quadratic autonomous ordinary differential equations by introducing an exponential quadratic term. This system can display a double-scroll chaotic a... This paper proposes a new robust chaotic system of three-dimensional quadratic autonomous ordinary differential equations by introducing an exponential quadratic term. This system can display a double-scroll chaotic attractor with only two equilibria, and can be found to be robust chaotic in a very wide parameter domain with positive maximum Lyapunov exponent. Some basic dynamical properties and chaotic behaviour of novel attractor are studied. By numerical simulation, this paper verifies that the three-dimensional system can also evolve into periodic and chaotic behaviours by a constant controller. 展开更多
关键词 ATTRACTOR chaotic system exponential quadratic term constant controller
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Carbon Sequestration in Soil Humic Substances Under Long-Term Fertilization in a Wheat-Maize System from North China 被引量:12
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作者 SONG Xiang-yun LIU Shu-tang +2 位作者 LIU Qing-hua ZHANG Wen-ju HU Chun-guang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第3期562-569,共8页
The changes in humic substances (HS) is fundamental in detecting soil carbon sequestration mechanisms in natural and cultivated environments. Based on a long-term trial, the amounts of water dissolved substances (... The changes in humic substances (HS) is fundamental in detecting soil carbon sequestration mechanisms in natural and cultivated environments. Based on a long-term trial, the amounts of water dissolved substances (WSS), humic acid (HA), fulvic acid (FA) and humin (HU) were determined to explore the impact of long-term fertilization on HS. Increases in the amounts of WSS, HA, FA and HU were significant different among the treatments with manure. A significant correlation was found between the increased soil organic carbon (SOC) and HS (R^2=0.98, P〈0.01). The change in the E4/E6 ratio was significantly correlated with the increased SOC (R2=0.88, P〈0.01), HA (R^2=0.91, P〈0.01), FA (R^2=0.91, P〈0.01) and HU (R^2=0.88, P〈0.01). The cluster was mainly divided into two parts as manure fertilization and inorganic fertilization, based on the increases in HA, FA and HU. These results suggest that long term fertilization with manure favours carbon sequestration in HS and is mainly stabilized as HU, while the HA becomes more aliphatic. We conclude that increases in SOC can be linked to changes in the molecular characteristics of HS fractions under long term fertilization. 展开更多
关键词 carbon sequestration humic acid HUMIN long term fertilization E4/E6 ratio
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Carbon sequestration rate,nitrogen use efficiency and rice yield responses to long-term substitution of chemical fertilizer by organic manure in a rice–rice cropping system 被引量:3
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作者 Nafiu Garba HAYATU LIU Yi-ren +7 位作者 HAN Tian-fu Nano Alemu DABA ZHANG Lu SHEN Zhe LI Ji-wen Haliru MUAZU Sobhi Faid LAMLOM ZHANG Hui-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第9期2848-2864,共17页
Combined application of chemical fertilizers with organic amendments was recommended as a strategy for improving yield,soil carbon storage,and nutrient use efficiency.However,how the long-term substitution of chemical... Combined application of chemical fertilizers with organic amendments was recommended as a strategy for improving yield,soil carbon storage,and nutrient use efficiency.However,how the long-term substitution of chemical fertilizer with organic manure affects rice yield,carbon sequestration rate(CSR),and nitrogen use efficiency(NUE)while ensuring environmental safety remains unclear.This study assessed the long-term effect of substituting chemical fertilizer with organic manure on rice yield,CSR,and NUE.It also determined the optimum substitution ratio in the acidic soil of southern China.The treatments were:(i)NPK0,unfertilized control;(ii)NPK1,100%chemical nitrogen,phosphorus,and potassium fertilizer;(iii)NPKM1,70%chemical NPK fertilizer and 30%organic manure;(iv)NPKM2,50%chemical NPK fertilizer and 50%organic manure;and(v)NPKM3,30%chemical NPK fertilizer and 70%organic manure.Milk vetch and pig manure were sources of manure for early and late rice seasons,respectively.The result showed that SOC content was higher in NPKM1,NPKM2,and NPKM3 treatments than in NPK0 and NPK1 treatments.The carbon sequestration rate increased by 140,160,and 280%under NPKM1,NPKM2,and NPKM3 treatments,respectively,compared to NPK1 treatment.Grain yield was 86.1,93.1,93.6,and 96.5%higher under NPK1,NPKM1,NPKM2,and NPKM3 treatments,respectively,compared to NPK0 treatment.The NUE in NPKM1,NPKM2,and NPKM3 treatments was higher as compared to NPK1 treatment for both rice seasons.Redundancy analysis revealed close positive relationships of CSR with C input,total N,soil C:N ratio,catalase,and humic acids,whereas NUE was closely related to grain yield,grain N content,and phenol oxidase.Furthermore,CSR and NUE negatively correlated with humin acid and soil C:P and N:P ratios.The technique for order of preference by similarity to ideal solution(TOPSIS)showed that NPKM3 treatment was the optimum strategy for improving CSR and NUE.Therefore,substituting 70%of chemical fertilizer with organic manure could be the best management option for increasing CSR and NUE in the paddy fields of southern China. 展开更多
关键词 carbon sequestration chemical fertilizer long term organic manure nitrogen use efficiency paddy rice
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Perturbation to Symmetries and Adiabatic Invariants of Nonholonomic System in Terms of Quasi-coordinates 被引量:4
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作者 CHEN Xiang-Wei ZHAO Yong-Hong LI Yan-Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5X期773-778,共6页
Based on the theory of Lie symmetries and conserved quantities, the exact invariants and adiabatic invariants of nonholonomic system in terms of quasi-coordinates are studied. The perturbation to symmetries for the no... Based on the theory of Lie symmetries and conserved quantities, the exact invariants and adiabatic invariants of nonholonomic system in terms of quasi-coordinates are studied. The perturbation to symmetries for the nonholonomic system in terms of quasi-coordinates under small excitation is discussed. The concept of high-order adiabatic invariant is presented, and the forms of exact invariants and adiabatic invariants as well as the conditions for their existence are given. Then the corresponding inverse problem is studied. 展开更多
关键词 nonholonomic system in terms of quasi-coordinates PERTURBATION exact invariant adiabatic invariant
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Long-term system load forecasting based on data-driven linear clustering method 被引量:18
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作者 Yiyan LI Dong HAN Zheng YAN 《Journal of Modern Power Systems and Clean Energy》 SCIE EI 2018年第2期306-316,共11页
In this paper, a data-driven linear clustering(DLC) method is proposed to solve the long-term system load forecasting problem caused by load fluctuation in some developed cities. A large substation load dataset with a... In this paper, a data-driven linear clustering(DLC) method is proposed to solve the long-term system load forecasting problem caused by load fluctuation in some developed cities. A large substation load dataset with annual interval is utilized and firstly preprocessed by the proposed linear clustering method to prepare for modelling.Then optimal autoregressive integrated moving average(ARIMA) models are constructed for the sum series of each obtained cluster to forecast their respective future load. Finally, the system load forecasting result is obtained by summing up all the ARIMA forecasts. From error analysis and application results, it is both theoretically and practically proved that the proposed DLC method can reduce random forecasting errors while guaranteeing modelling accuracy, so that a more stable and precise system load forecasting result can be obtained. 展开更多
关键词 Long-term system load forecasting Datadriven LINEAR clustering AUTOREGRESSIVE integrated moving average(ARIMA) Error analysis
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Ionization energies and term energies of the ground states 1s^22s of lithium-like systems 被引量:2
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作者 李金英 王治文 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期187-191,共5页
We extend the Hamiltonian method of the full-core plus correlation (FCPC) by minimizing the expectation value to calculate the non-relativistic energies and the wave functions of ls22s states for the lithium-like sy... We extend the Hamiltonian method of the full-core plus correlation (FCPC) by minimizing the expectation value to calculate the non-relativistic energies and the wave functions of ls22s states for the lithium-like systems from Z = 41 to 50. The mass-polarization and the relativistic corrections including the kinetic-energy correction, the Darwin term, the electron-electron contact term, and the orbit-orbit interaction are calculated perturbatively as first-order correction. The contribution from quantum electrodynamic (QED) is also explored by using the effective nuclear charge formula. The ionization potential and term energies of the ground states 1 s22s are derived and compared with other theoretical calculation results. It is shown that the FCPC methods are also effective for theoretical calculation of the ionic structure for high nuclear ion of lithium-like systems. 展开更多
关键词 lithium-like systems full core plus correlation ionization energy term energy
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Suppression of Chaotic Behaviors in a Complex Biological System by Disturbance Observer-based Derivative-Integral Terminal Sliding Mode 被引量:5
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作者 Dianwei Qian Hui Ding +1 位作者 SukGyu Lee Hyansu Bae 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第1期126-135,共10页
Coronary artery systems are a kind of complex biological systems. Their chaotic phenomena can lead to serious health problems and illness development. From the perspective of engineering, this paper investigates the c... Coronary artery systems are a kind of complex biological systems. Their chaotic phenomena can lead to serious health problems and illness development. From the perspective of engineering, this paper investigates the chaos suppression problem. At first, nonlinear dynamics of coronary artery systems are presented. To suppress the chaotic phenomena, the method of derivative-integral terminal sliding mode control is adopted. Since coronary artery systems suffer from uncertainties, the technique of disturbance observer is taken into consideration. The stability of such a control system that integrates the derivative-integral terminal sliding mode controller and the disturbance observer is proven in the sense of Lyapunov. To verify the feasibility and effectiveness of the proposed strategy, simulation results are illustrated in comparison with a benchmark. 展开更多
关键词 Biological systems chaos suppression coronary artery nonlinear dynamics sliding mode control(SMC)
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Long Term Assessment of a Grid Connected Solar PV System in Sydney 被引量:2
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作者 Saad Odeh 《Journal of Energy and Power Engineering》 2016年第10期591-599,共9页
This paper assesses 4 years of operation of a 1.75 kW roof top solar PV system installed in a Sydney suburban house. The system consists of 10 PV panels, a DC/AC inverter, and a grid connected gross meter. Solar elect... This paper assesses 4 years of operation of a 1.75 kW roof top solar PV system installed in a Sydney suburban house. The system consists of 10 PV panels, a DC/AC inverter, and a grid connected gross meter. Solar electricity delivered to grid is verified with the results from a computer simulation package (PVSYST) by adopting the installed component specifications, operation conditions, and weather data of the site. The results show high consistency between the values of energy delivered to the grid measured by the energy company and the energy estimated by system simulation. New system performance indicator is developed and called the optimum performance compliance ratio (PCR). It is a measure of the compliance of the output of the designed PV system with the output which would be produced by the same system with a solar tracker. This indicator provides system designers, contractors and energy providers with the actual capacity of the system that they can offer the end-users. 展开更多
关键词 Long term assessment grid connected PV system solar electricity performance indicator.
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Effect of Long-Term Application of K Fertilizer and Wheat Straw to Soil on Crop Yield and Soil K Under Different Planting Systems 被引量:25
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作者 TAN De-shui JIN Ji-yun HUANG Shao-wen LI Shu-tian HE Ping 《Agricultural Sciences in China》 CAS CSCD 2007年第2期200-207,共8页
Effect of application of K fertilizer and wheat straw to soil on crop yield and status of soil K in the plough layer under different planting systems was studied. The experiments on long-term application of K fertiliz... Effect of application of K fertilizer and wheat straw to soil on crop yield and status of soil K in the plough layer under different planting systems was studied. The experiments on long-term application of K fertilizer and wheat straw to soil in Hebei fluvo aquic soil and Shanxi brown soil in northern China were begun in 1992. The results showed that K fertilizer and straw could improve the yields of wheat and maize with the order of NPK + St 〉 NPK 〉 NP + St 〉 NP, and treatment of K fertilizer made a significant difference to NP, and the efficiency of K fertilizer in maize was higher than in wheat under rotation system of Hebei. In contrast with Shanxi, the wastage of soil potassium was a more serious issue in the rotation system in Hebei, only treatment of NPK + St showed a surplus of potassium and the others showed a wane. K fertilizer and straw could improve the content of water-soluble K, nonspecifically adsorbed K, non-exchangeable K, mineral K, and total K in contrast to NP; however, K fertilizer and straw reduce the proportion of mineral K and improve proportion of other forms of potassium in the two locating sites. Compared with the beginning of orientation, temporal variability character of soil K content and proportion showed a difference between the two soil types; furthermore, there was a decrease in the content of mineral K and total K simultaneously in the two locating sites. As a whole, the effect of K fertilizer applied to soil directly excelled to wheat straw to soil. Wheat straw to soil was an effective measure to complement potassium to increase crop yield and retard the decrease of soil K. 展开更多
关键词 different planting systems long-term application of K fertilizer wheat straw to soil crop yield soil K
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Wavelet time series MPARIMA modeling for power system short term load forecasting
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作者 冉启文 单永正 +1 位作者 王建赜 王骐 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第1期11-18,共8页
The wavelet power system short term load forecasting(STLF) uses a mulriple periodical autoregressive integrated moving average(MPARIMA) model to model the mulriple near periodicity, nonstationarity and nonlinearity ex... The wavelet power system short term load forecasting(STLF) uses a mulriple periodical autoregressive integrated moving average(MPARIMA) model to model the mulriple near periodicity, nonstationarity and nonlinearity existed in power system short term quarter hour load time series, and can therefore accurately forecast the quarter hour loads of weekdays and weekends, and provide more accurate results than the conventional techniques, such as artificial neural networks and autoregressive moving average(ARMA) models test results. Obtained with a power system networks in a city in Northeastern part of China confirm the validity of the approach proposed. 展开更多
关键词 wavelet forecasting method short term load forecast MPARIMA model
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Medium Term Load Forecasting for Jordan Electric Power System Using Particle Swarm Optimization Algorithm Based on Least Square Regression Methods
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作者 Mohammed Hattab Mohammed Ma’itah +2 位作者 Tha’er Sweidan Mohammed Rifai Mohammad Momani 《Journal of Power and Energy Engineering》 2017年第2期75-96,共22页
This paper presents a technique for Medium Term Load Forecasting (MTLF) using Particle Swarm Optimization (PSO) algorithm based on Least Squares Regression Methods to forecast the electric loads of the Jordanian grid ... This paper presents a technique for Medium Term Load Forecasting (MTLF) using Particle Swarm Optimization (PSO) algorithm based on Least Squares Regression Methods to forecast the electric loads of the Jordanian grid for year of 2015. Linear, quadratic and exponential forecast models have been examined to perform this study and compared with the Auto Regressive (AR) model. MTLF models were influenced by the weather which should be considered when predicting the future peak load demand in terms of months and weeks. The main contribution for this paper is the conduction of MTLF study for Jordan on weekly and monthly basis using real data obtained from National Electric Power Company NEPCO. This study is aimed to develop practical models and algorithm techniques for MTLF to be used by the operators of Jordan power grid. The results are compared with the actual peak load data to attain minimum percentage error. The value of the forecasted weekly and monthly peak loads obtained from these models is examined using Least Square Error (LSE). Actual reported data from NEPCO are used to analyze the performance of the proposed approach and the results are reported and compared with the results obtained from PSO algorithm and AR model. 展开更多
关键词 MEDIUM term Load Forecasting Particle SWARM Optimization Least SQUARE Regression Methods
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Long Term Application of a Vehicle-Based Health Monitoring System to Short and Medium Span Bridges and Damage Detection Sensitivity
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作者 Ayaho Miyamoto Jari Puttonen Akito Yabe 《Engineering(科研)》 2017年第2期68-122,共55页
Largest portion of the bridge stock in almost any country and bridge owning organisation consists on ordinary bridges that has short or medium spans and are now deteriorating due to aging, etc. Therefore, it is becomi... Largest portion of the bridge stock in almost any country and bridge owning organisation consists on ordinary bridges that has short or medium spans and are now deteriorating due to aging, etc. Therefore, it is becoming an important social concern to develop and put to practical use simple and efficient health monitoring systems for existing short and medium span (10 - 30 m) bridges. In this paper, one practical solution to the problem for condition assessment of short and medium span bridges was discussed. A vehicle-based measurement with a public bus as part of a public transit system (called “Bus monitoring system”) has been developed to be capable of detecting damage that may affect the structural safety of a bridge from long term vibration measurement data collected while the vehicle (bus) crossed the target bridges. This paper systematically describes how the system has been developed. The bus monitoring system aims to detect the transition from the damage acceleration period, in which the structural safety of an aged bridge declines sharply, to the deterioration period by continually monitoring the bridge of interest. To evaluate the practicality of the newly developed bus monitoring system, it has been field-tested over a period of about four years by using an in-service fixed-route bus operating on a bus route in the city of Ube, Yamaguchi Prefecture, Japan. The verification results thus obtained are also described in this paper. This study also evaluates the sensitivity of “characteristic deflection”, which is a bridge (health) condition indicator used by the bus monitoring system, in damage detection. Sensitivity of “characteristic deflection” is verified by introducing artificial damage into a bridge that has ended its service life and is awaiting removal. As the results, it will be able to make a rational long-term health monitoring system for existing short and mediumspan bridges, and then the system helps bridge administrators to establish the rational maintenance strategies. 展开更多
关键词 SHORT and MEDIUM SPAN Bridge Long term MONITORING Public Bus Health MONITORING system Condition Assessment Damage Detection Characteristic DEFLECTION Sensitivity
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Soil carbon sequestration under long-term rice-based cropping systems of purple soil in Southwest China 被引量:10
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作者 FAN Hong-zhu CHEN Qing-rui +4 位作者 QIN Yu-sheng CHEN Kun TU Shi-hua XU Ming-gang ZHANG Wen-ju 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第12期2417-2425,共9页
Carbon sequestration in agricultural soils is a complex process controlled by farming practices, climate and some other environment factors. Since purple soils are unique in China and used as the main cropland in Sich... Carbon sequestration in agricultural soils is a complex process controlled by farming practices, climate and some other environment factors. Since purple soils are unique in China and used as the main cropland in Sichuan Basin of China, it is of great importance to study and understand the impacts of different fertilizer amendments on soil organic carbon(SOC) changes with time. A research was carried out to investigate the relationship between soil carbon sequestration and organic carbon input as affected by different fertilizer treatments at two long-term rice-based cropping system experiments set up in early 1980 s. Each experiment consisted of six identical treatments, including(1) no fertilizer(CK),(2) nitrogen and phosphorus fertilizers(NP),(3) nitrogen, phosphorus and potassium fertilizers(NPK),(4) fresh pig manure(M),(5) nitrogen and phosphorus fertilizers plus manure(MNP), and(6) nitrogen, phosphorus and potassium fertilizers plus manure(MNPK). The results showed that annual harvestable carbon biomass was the highest in the treatment of MNPK, followed by MNP and NPK, then M and NP, and the lowest in CK. Most of fertilizer treatments resulted in a significant gain in SOC ranging from 6.48 to 2 9.13% compared with the CK, and raised soil carbon sequestration rate to 0.10–0.53 t ha–1 yr-1. Especially, addition of manure on the basis of mineral fertilizers was very conducive to SOC maintenance in this soil. SOC content and soil carbon sequestration rate under balanced fertilizer treatments(NPK and MNPK) in the calcareous purple soil(Suining) were higher than that in the acid purple soil(Leshan). But carbon conversion rate at Leshan was 11.00%, almost 1.5 times of that(7.80%) at Suining. Significant linear correlations between soil carbon sequestration and carbon input were observed at both sites, signifying that the purple soil was not carbon-saturated and still had considerable potential to se questrate more carbon. 展开更多
关键词 rice-based cropping systems long-term fertilization soil organic carbon purple soil
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Presenting Knowledge System of International Trade Terms in Business English Learners' Dictionaries
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作者 HE Jia-ning KHOU Zhi-yi +2 位作者 XIE Zi-jun WU Ming-hui XU Rong 《Journal of Literature and Art Studies》 2018年第8期1275-1281,共7页
Dictionaries should present business encyclopedic knowledge as well as business linguistic knowledge. This paper, taking Incoterms for international trade as an example (with "CIF" as the case for analysis), intro... Dictionaries should present business encyclopedic knowledge as well as business linguistic knowledge. This paper, taking Incoterms for international trade as an example (with "CIF" as the case for analysis), introduces 7 types of dictionary structures (overall structure, frame stzucture/megastrncture, macrostructure, microstzucture, distribution structure, cross-reference stzucture/mediostrncture and access structure), summarizes the knowledge system of international trade terms (consisting of "international trade", "sets of rules of international trade terms", "Incoterms 2010", and "CIF"), and illustrates the methods of systematically presenting the knowledge system of international trade terms through dictionary structures in an English-English-Chinese bilingualized business English learners' dictionary with Oxford Business English Dictionary for Learners of English (New Edition) as a reference. Such presentation is intended for enhancing business English learners as dictionary users to grasp the knowledge of international trade terms as a whole. 展开更多
关键词 business English learners' dictionary (BELD) dictionary structure terminological knowledge system international trade term knowledge presentation business English
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Study on the operation effect of long term care insurance system in Qingdao
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作者 WU Yuhua 《International English Education Research》 2016年第6期65-67,共3页
Population aging has become a global social problem, the problem in our country has become the core of the aging problem. With the gradual aging of the elderly, loss of energy, loss of energy has become the norm for t... Population aging has become a global social problem, the problem in our country has become the core of the aging problem. With the gradual aging of the elderly, loss of energy, loss of energy has become the norm for the elderly or sick elderly. According to the Ministry of Civil Affairs statistics, as of the end of 2014, the number of disabled elderly in China reached 35 million, about 90% of the disabled elderly need professional care services and professional treatment to ease the pain. In order to deal with the social problems brought about by the aging of the population, in July 1, 2012, Qingdao City, the first in the country to establish a long-term health care insurance system, has taken a key step to crack the problem of aging. In this paper, the situation of Qingdao long term care insurance system as the research object, taking Qingdao city as study sites, according to statistical data analysis of the implementation effect of long-term local health care policy, and through questionnaires and interviews in the form of local residents to participate in the investigation of awareness, and perception. At the same time, the results of the survey on long-term health care insurance system in Qingdao, the operation effect of the overall analysis. 展开更多
关键词 Long term health care insurance system Qingdao City operation effect long term care
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Existence and Multiplicity of Positive Solutions to Quasilinear Elliptic Systems Involving Multiple Hardy-Type Terms and Concave-Convex Nonlinearities
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作者 Tsing-San Hsu 《Journal of Mathematics and System Science》 2013年第3期150-161,共12页
Regular semilinear elliptic systems have been studied extensively and many conclusions have been established. However, the elliptic systems involving the Hardy inequality and concave-convex nonlinearities have seldom ... Regular semilinear elliptic systems have been studied extensively and many conclusions have been established. However, the elliptic systems involving the Hardy inequality and concave-convex nonlinearities have seldom been studied and we only find few results. Thus it is necessary for us to investigate the related singular systems deeply. In this paper, a quasilinear elliptic system is investigated, which involves multiple Hardy-type terms and concave-convex nonlinearities. To the best of our knowledge, such a problem has not been discussed. By using a variational method involving the Nehari manifold and some analytical techniques, we prove that there exist at least two positive solutions to the system. 展开更多
关键词 Quasilinear elliptic system multiple Hardy-type terms variational method Nehari manifold.
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Long term care insurance system of Germany
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作者 ZHENG ChangHao 《International English Education Research》 2016年第6期85-87,共3页
1990s, Germany is facing a serious problem of population aging, in 1995, of the population over the age of 60 in Germany, the proportion of the total population is as high as 21%, the proportion is expected to rise to... 1990s, Germany is facing a serious problem of population aging, in 1995, of the population over the age of 60 in Germany, the proportion of the total population is as high as 21%, the proportion is expected to rise to 36% in 2030. The growing demand for long-term care services by the rapid aging of population is the basic background of the introduction of the long-term care insurance system in Germany. 展开更多
关键词 long term care insurance system GERMANY
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Basic Terms in Shiology-Revealing the Connotation and Extension of the Core Concept of Shiance Cognition
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作者 Liu Guangwei 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第4期86-96,共11页
Shiology,abbreviated from the study of shiance,stands as a"disciplinary category"level knowledge system.Within the Chinese educational system's subject catalog,it is an extension of agricultural science(... Shiology,abbreviated from the study of shiance,stands as a"disciplinary category"level knowledge system.Within the Chinese educational system's subject catalog,it is an extension of agricultural science(09),and it is a knowledge system that integrates the eater needs,food acquisition and shiance order.Cognition of previously unrecognized objects requires new concepts,and the construction of a new knowledge system cannot be separated from the support of new concepts.Shiance knowledge system is a huge collection of shiance concepts,and this research limits its discussion to the connotations and extensions of four core groups of concepts:shiance,food,eaters,and eating.These core concepts of shiance knowledge also serve as the foundational terms for constructing the shiology framework.Establishing the foundational terms and definitions of shiology is a fundamental research endeavor.If one were to liken the shiology framework to a building,then its foundational terms are akin to the"bricks";defining these terms is comparable to setting standards for these"bricks",facilitating the construction of a more robust structure.The basic words discussed in this research include 34 in the category of"shiance",31 in the category of"food",seven in the category of"eaters"and 16 in the category of"eating".These basic words play a fundamental and leading role in the process of constructing the system of shiology system,and they are used in the names of 40 subjects in the 53 basic shiology systems.The absence and narrowing of cognitive concepts are at the root of the lack of systematic governance of human shiance issues. 展开更多
关键词 term shiology shiology term shiance FOOD eater eatin
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Efficient Finite Difference WENO Scheme for Hyperbolic Systems withNon-conservativeProducts
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作者 Dinshaw S.Balsara Deepak Bhoriya +1 位作者 Chi-Wang Shu Harish Kumar 《Communications on Applied Mathematics and Computation》 EI 2024年第2期907-962,共56页
Higher order finite difference weighted essentially non-oscillatory(WENO)schemes have been constructed for conservation laws.For multidimensional problems,they offer a high order accuracy at a fraction of the cost of ... Higher order finite difference weighted essentially non-oscillatory(WENO)schemes have been constructed for conservation laws.For multidimensional problems,they offer a high order accuracy at a fraction of the cost of a finite volume WENO or DG scheme of the comparable accuracy.This makes them quite attractive for several science and engineering applications.But,to the best of our knowledge,such schemes have not been extended to non-linear hyperbolic systems with non-conservative products.In this paper,we perform such an extension which improves the domain of the applicability of such schemes.The extension is carried out by writing the scheme in fluctuation form.We use the HLLI Riemann solver of Dumbser and Balsara(J.Comput.Phys.304:275-319,2016)as a building block for carrying out this extension.Because of the use of an HLL building block,the resulting scheme has a proper supersonic limit.The use of anti-diffusive fluxes ensures that stationary discontinuities can be preserved by the scheme,thus expanding its domain of the applicability.Our new finite difference WENO formulation uses the same WENO reconstruction that was used in classical versions,making it very easy for users to transition over to the present formulation.For conservation laws,the new finite difference WENO is shown to perform as well as the classical version of finite difference WENO,with two major advantages:(i)It can capture jumps in stationary linearly degenerate wave families exactly.(i)It only requires the reconstruction to be applied once.Several examples from hyperbolic PDE systems with non-conservative products are shown which indicate that the scheme works and achieves its design order of the accuracy for smooth multidimensional flows.Stringent Riemann problems and several novel multidimensional problems that are drawn from compressible Baer-Nunziato multiphase flow,multiphase debris flow and twolayer shallow water equations are also shown to document the robustness of the method.For some test problems that require well-balancing we have even been able to apply the scheme without any modification and obtain good results.Many useful PDEs may have stiff relaxation source terms for which the finite difference formulation of WENO is shown to provide some genuine advantages. 展开更多
关键词 Hyperbolic PDEs Numerical schemes Non-conservative products Stiff source terms Finite difference WENO
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Winding Function Model-based Performance Evaluation of a PM Transverse Flux Generator for Applications in Direct-drive Systems
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作者 Mehrage Ghods Jawad Faiz Ali A Pourmoosa 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第2期216-226,共11页
The magnetic flux in a permanent magnet transverse flux generator(PMTFG) is three-dimensional(3D), therefore, its efficacy is evaluated using 3D magnetic field analysis. Although the 3D finite-element method(FEM) is h... The magnetic flux in a permanent magnet transverse flux generator(PMTFG) is three-dimensional(3D), therefore, its efficacy is evaluated using 3D magnetic field analysis. Although the 3D finite-element method(FEM) is highly accurate and reliable for machine simulation, it requires a long computation time, which is crucial when it is to be used in an iterative optimization process. Therefore, an alternative to 3DFEM is required as a rapid and accurate analytical technique. This paper presents an analytical model for PMTFG analysis using winding function method. To obtain the air gap MMF distribution, the excitation magneto-motive force(MMF) and the turn function are determined based on certain assumptions. The magnetizing inductance, flux density, and back-electro-magnetomotive force of the winding are then determined. To assess the accuracy of the proposed method, the analytically calculated parameters of the generator are compared to those obtained by a 3D-FEM. The presented method requires significantly shorter computation time than the 3D-FEM with comparable accuracy. 展开更多
关键词 Index terms—Permanent magnet transverse flux generator Winding function 3D-FEM Cogging torque PROTOTYPING
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