Employees’innovative performance determines an organization’s innovation,which critically impacts its structural optimization and sustainability.Applying expectancy theory,we examined how and when the Pygmalion effe...Employees’innovative performance determines an organization’s innovation,which critically impacts its structural optimization and sustainability.Applying expectancy theory,we examined how and when the Pygmalion effect occurs in the relationship between leaders’expectations of innovation and employee innovative behavior.Our sample comprised 201 frontline employees(female=31.84%;mean age=41.48 years,SD=7.97 years)in a Chinese coal enterprise,who completed surveys on innovation expectations of leaders,expected positive performance outcomes,innovative self-efficacy and innovative behavior.The results revealed that employees’expected positive performance outcomes mediated the positive relationship between leaders’innovation expectations and their innovative behavior.Employees’innovative self-efficacy positively moderated the relationship between their expected positive performance outcomes and innovative behavior,with this relationship being stronger for employees with high innovative self-efficacy.Moreover,we validated the moderated mediation model.Findings suggest that leaders can stimulate employee innovative behavior through expressing expectations and they also need to consider the boundary conditions.展开更多
Background There is a lack of research examining the interplay between objectively measured physical activity volume and intensity with life expectancy.The purpose of the study was to investigate the interplay between...Background There is a lack of research examining the interplay between objectively measured physical activity volume and intensity with life expectancy.The purpose of the study was to investigate the interplay between objectively measured PA volume and intensity profiles with modeled life expectancy in women and men within the UK Biobank cohort study and interpret findings in relation to brisk walking.Methods Individuals from UK Biobank with wrist-worn accelerometer data were included.The average acceleration and intensity gradient were extracted to describe the physical activity volume and intensity profile.Mortality data were obtained from national registries.Adjusted life expectancies were estimated using parametric flexible survival models.Results 40,953(57.1%)women(median age=61.9 years)and 30,820(42.9%)men(63.1 years)were included.Over a median follow-up of 6.9 years,there were 1719(2.4%)deaths(733 in women;986 in men).At 60 years,life expectancy was progressively longer for higher physical activity volume and intensity profiles,reaching 95.6 years in women and 94.5 years in men at the 90th centile for both volume and intensity,corresponding to 3.4 additional years(95%confidence interval(95%CI):2.4-4.4)in women and 4.6 additional years(95%CI:3.6-5.6)in men compared to those at the 10th centiles.An additional 10-min or 30-min daily brisk walk was associated with 0.9(95%CI:0.5-1.3)and 1.4 years(95%CI:0.9-1.9)longer life expectancy,respectively,in inactive women;and 1.4 years(95%CI:1.0-1.8)and 2.5(95%CI:1.9-3.1)in inactive men.Conclusion Higher physical activity volumes were associated with longer life expectancy,with a higher physical activity intensity profile further adding to a longer life.Adding as little as a 10-min brisk walk to daily activity patterns may result in a meaningful benefit to life expectancy.展开更多
In the new released article of the Journal of Sport and Health Science,Zaccardi et al.1 provide compelling evidence that engaging in higher volumes and intensities of physical activity(PA)increases life expectancy in ...In the new released article of the Journal of Sport and Health Science,Zaccardi et al.1 provide compelling evidence that engaging in higher volumes and intensities of physical activity(PA)increases life expectancy in older men and women enrolled in the UK Biobank study.The study included 30,820 men and 40,953 women with median ages of 63.1 years and 61.9 years,respectively.Study participants wore accelerometers to track their time and intensity of PA for 7 days at baseline.展开更多
The repeated failures of any equipment or systems are modeled as a renewal process. The management needs an assessment of the number of future failures to allocate the resources needed for fast repairs. Based on the i...The repeated failures of any equipment or systems are modeled as a renewal process. The management needs an assessment of the number of future failures to allocate the resources needed for fast repairs. Based on the idea of expectation by conditioning, special Volterra-type integral equations are derived for general types of repairs, considering the length of repair and reduced degradation of the idle object. In addition to minimal repair and failure replacement, partial repairs are also discussed when the repair results in reduction of the number of future failures or decreases the effective age of the object. Numerical integration-based algorithm and simulation study are performed to solve the resulting integral equation. Since the geometry degradation in different dimensions of a rail track and controlling and maintaining defects are of importance, a numerical example using the rail industry data is conducted. Expected number of failures of different failure type modes in rail track is calculated within a two-year interval. Results show that within a two-year period, anticipated occurrences of cross level failures, surface failures, and DPI failures are 2.4, 3.8, and 5.8, respectively.展开更多
The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the...The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the equivalent conditions of complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space.The results complement the corresponding results in probability space to those for sequences of independent,identically distributed random variables under sublinear expectation space.展开更多
This study investigates the return dynamics,volatility structure,and risk characteristics of five representative S&P 500 stocks:Johnson&Johnson,Microsoft,NVIDIA,Coca-Cola,and Home Depot,using ARMA-GARCH models...This study investigates the return dynamics,volatility structure,and risk characteristics of five representative S&P 500 stocks:Johnson&Johnson,Microsoft,NVIDIA,Coca-Cola,and Home Depot,using ARMA-GARCH models.Descriptive statistics and diagnostic tests confirm non-normality,negative skewness,fat tails,and volatility clustering,providing strong justification for conditional mean-variance modelling.Optimal model specifications are selected via the Bayesian Information Criterion,with EGARCH frameworks generally outperforming alternative GARCH variants in capturing asymmetric volatility responses.Rolling-window forecasts for 2024Q1 show that the models generate stable and reliable volatility predictions for low-volatility stocks(JNJ,KO),while performance is weaker for highly volatile stocks(NVDA),highlighting structural limitations under extreme market shifts.To evaluate risk management implications,one percent Value-at-Risk and expected shortfall were computed and backtested.Results indicated conservative tail-risk forecasts,with violation rates well within acceptable thresholds.Portfolio applications are further explored by constructing the Global Minimum Variance Portfolio(GMVP)and the Maximum Sharpe Ratio(Max SR)portfolio using rolling covariance estimates.Out-of-sample backtesting demonstrated that the GMVP delivered low volatility but modest returns,whereas the Max SR portfolio achieved significantly higher performance,consistent with the risk-return trade-off.Overall,the findings confirm that ARMA-GARCH models are effective tools for modelling conditional volatility and informing dynamic asset allocation.However,their limited adaptability to jump risk and nonlinear structural breaks underscores the need for more advanced modelling approaches in high-volatility environments.展开更多
Variable-fidelity(VF)surrogate models have received increasing attention in engineering design optimization as they can approximate expensive high-fidelity(HF)simulations with reduced computational power.A key challen...Variable-fidelity(VF)surrogate models have received increasing attention in engineering design optimization as they can approximate expensive high-fidelity(HF)simulations with reduced computational power.A key challenge to building a VF model is devising an adaptive model updating strategy that jointly selects additional low-fidelity(LF)and/or HF samples.The additional samples must enhance the model accuracy while maximizing the computational efficiency.We propose ISMA-VFEEI,a global optimization framework that integrates an Improved Slime-Mould Algorithm(ISMA)and a Variable-Fidelity Expected Extension Improvement(VFEEI)learning function to construct a VF surrogate model efficiently.First,A cost-aware VFEEI function guides the adaptive LF/HF sampling by explicitly incorporating evaluation cost and existing sample proximity.Second,ISMA is employed to solve the resulting non-convex optimization problem and identify global optimal infill points for model enhancement.The efficacy of ISMA-VFEEI is demonstrated through six numerical benchmarks and one real-world engineering case study.The engineering case study of a high-speed railway Electric Multiple Unit(EMU),the optimization objective of a sanding device attained a minimum value of 1.546 using only 20 HF evaluations,outperforming all the compared methods.展开更多
As an old Chinese saying goes,knowledge changes fate.An ordinary college student carries expectations of several generations of his or her family.Consequently,a vast majority of high school graduates applying for coll...As an old Chinese saying goes,knowledge changes fate.An ordinary college student carries expectations of several generations of his or her family.Consequently,a vast majority of high school graduates applying for college prefer to choose colleges and majors with good employment prospects.Two years ago,facing hundreds of majors,I was caught in a dilemma.Law seemed appealing,as it could offer a high income and a worry-free life.展开更多
Objective:The aim of this study was to investigate the health expectations(HEs)in patients with diabetes and the factors affecting it using an integrative systematic review.Methods:A comprehensive literature search wa...Objective:The aim of this study was to investigate the health expectations(HEs)in patients with diabetes and the factors affecting it using an integrative systematic review.Methods:A comprehensive literature search was conducted in databases including PubMed,Scopus,Science Direct,Google Scholar,ProQuest,CINAHL,SID,Iran Doc,and Magiran without time limitation using related keywords.The systematic literature search was performed using a guide provided by York University.Results:From a total of 1883 articles,17 of them finally met the eligibility criteria.According to the findings of this study,HE of diabetic patients was included in four categories:“dynamism,”“consequentialism,”“comprehensive care,”and“access to facilities.”Also,these expectations can be influenced by various factors,including“developments in societies,”“changing the conditions of health care systems,”and“individual factors.”Conclusions:Health professionals should pay attention to the expectations of diabetic patients who are involved in complex disease conditions and consider meeting them as a key factor in providing patient-centered care,improving health outcomes,and patient satisfaction.展开更多
In this paper,an index modulation(IM)aided uplink orthogonal time frequency space modulation(OTFS)structure for sparse code multiple access(SCMA)is proposed.To be more specific,the information bits are firstly partiti...In this paper,an index modulation(IM)aided uplink orthogonal time frequency space modulation(OTFS)structure for sparse code multiple access(SCMA)is proposed.To be more specific,the information bits are firstly partitioned for transmit antenna(TA)selection and sparse codeword mapping,respectively.Subsequently,the codewords deployed on the 2-dimensional(2D)delay-Doppler(DD)plane are transmitted by the selected TA,and the superimposed signals are jointly detected at the receiver.Furthermore,a low-complexity zero-embedded expectation propagation(ZE-EP)detector is conceived,where the codebooks are extended with zero vectors to reflect the silent indices.The simulation results demonstrate that the proposed IM-OTFS-SCMA system is capable of providing significant performance gain over the OTFS-SCMA counterpart.展开更多
Objective:This study aimed to investigate the learning expectations of undergraduate nursing students regarding the flipped Health Assessment course.Methods:This descriptive,qualitative study was conducted at a medica...Objective:This study aimed to investigate the learning expectations of undergraduate nursing students regarding the flipped Health Assessment course.Methods:This descriptive,qualitative study was conducted at a medical university in Fuzhou,Fujian Province,China.An interview outline was designed based on the core dimensions of Expectation Confirmation Theory(expectation sources,expectation content,and expectation importance).Thirty second-year undergraduate nursing students who had completed first-year basic medical courses and were about to take the flipped Health Assessment course were interviewed between June and July 2022.Interview data were analyzed using qualitative content analysis.Results:Five major themes and thirteen subthemes were identified.Theme 1 was expectation sourcesperceived learning difficulties from past experiences,which included four subthemes:insufficient autonomous learning ability,confusion regarding learning methods,insufficient engagement in learning,and low professional identity.Theme 2 included knowledge and information expectations,which comprised three subthemes:knowledge to improve professional competence,knowledge to enhance academic competitiveness,and knowledge to boost self-efficacy.Theme 3 comprised logical expectations and included two subthemes:flexible teaching methods and efficient instructional tools.Theme 4,pleasure expectations,included two subthemes:vivid teaching styles and diversified teaching evaluations.Theme 5 comprised professional value expectations and included two subthemes:teachers'responsible professional attitudes and gentle emotional support.Conclusion:Students'learning expectations originate from perceived learning difficulties,such as insufficient learning autonomy and engagement,confusion about learning methods,and a lack of professional identity.They showed various learning expectations for the flipped Health Assessment course,including knowledge and information,logic,pleasure,and professional value expectations.展开更多
With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely o...With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely obesity and neurodegeneration.展开更多
How do individuals adjust their savings and consumption behaviors in response to the combined effects of increased life expectancy and declining pension replacement rates?This study constructs a life-cycle model,using...How do individuals adjust their savings and consumption behaviors in response to the combined effects of increased life expectancy and declining pension replacement rates?This study constructs a life-cycle model,using changes in conditional survival probabilities as a proxy for shifts in individual life expectancy,to examine consumption behavior under the dual backdrop of prolonged longevity and a gradual decline in pension replacement rates.The results suggest that changes in life expectancy and pension replacement rates together explain 8.9%to 10.2%of the observed decline in consumption in recent years,with both variables playing equally significant explanatory roles.Furthermore,we find that,to fully offset the negative impact of increased life expectancy on consumption,the pension replacement rate must reach at least 82%.These findings offer theoretical and policy implications for improving the quality of life in later years among enterprise employees in the context of population aging.展开更多
Assume that{a_(i),−∞<i<∞}is an absolutely summable sequence of real numbers.We establish the complete q-order moment convergence for the partial sums of moving average processes{X_(n)=Σ_(i=−∞)^(∞)a_(i)Y_(i+...Assume that{a_(i),−∞<i<∞}is an absolutely summable sequence of real numbers.We establish the complete q-order moment convergence for the partial sums of moving average processes{X_(n)=Σ_(i=−∞)^(∞)a_(i)Y_(i+n),n≥1}under some proper conditions,where{Yi,-∞<i<∞}is a doubly infinite sequence of negatively dependent random variables under sub-linear expectations.These results extend and complement the relevant results in probability space.展开更多
This study investigated the relationship between parental cognitive ability and child logical reasoning ability,and the role of academic expectation and family environment in that relationship.Based on the 2020 China ...This study investigated the relationship between parental cognitive ability and child logical reasoning ability,and the role of academic expectation and family environment in that relationship.Based on the 2020 China Family Panel Studies(CFPS)data,1491 children(girls ratio=53.78%;average grade=6.023 years,school grade standard deviation=1.825 years).Results following multiple regression model(OLS)show that the higher the parental cognitive ability,the higher the children’s logical reasoning ability.Secondly,parental academic expectation serves as a mediator between their cognitive ability and children’s logical reasoning ability for higher logical reasoning by children.Third,a possible family environment acts as a mediator in the relationship between parents’cognitive ability and children’s logical reasoning ability to be higher.We conclude from thesefindings that parents with high cognitive abilities can enhance their children’s logical reasoning skills not only by setting higher academic expectations,but also by cultivating a supportive family environment.Thesefindings imply a need for intervention to improve family quality of life to enhance children’s thinking abilities to optimize their academic learning.展开更多
This article studies optimal consumption-leisure, portfolio and retirement selection of an infinitely lived investor whose preference is formulated by a-maxmin expected CES utility which is to differentiate ambiguity ...This article studies optimal consumption-leisure, portfolio and retirement selection of an infinitely lived investor whose preference is formulated by a-maxmin expected CES utility which is to differentiate ambiguity and ambiguity attitude. Adopting the recursive multiple- priors utility and the technique of backward stochastic differential equations （BSDEs）, we transform the （^-maxmin expected CES utility into a classical expected CES utility under a new probability measure related to the degree of an investor＇s uncertainty. Our model investi- gates the optimal consumption-leisure-work selection, the optimal portfolio selection, and the optimal stopping problem. In this model, the investor is able to adjust her supply of labor flex- ibly above a certain minimum work-hour along with a retirement option. The problem can be analytically solved by using a variational inequality. And the optimal retirement time is given as the first time when her wealth exceeds a certain critical level. The optimal consumption-leisure and portfolio strategies before and after retirement are provided in closed forms. Finally, the distinctions of optimal consumption-leisure, portfolio and critical wealth level under ambiguity from those with no vagueness are discussed.展开更多
Magnitude and distance of major potential source are needed in order to determine duration time of artificial ground motion and to determine the type of response spectrum (near field or far field) when using the seism...Magnitude and distance of major potential source are needed in order to determine duration time of artificial ground motion and to determine the type of response spectrum (near field or far field) when using the seismic intensity zonation map. The magnitude probabilistic distribution function of seismic belt and the magnitude and space joint distribution function for given intensity of the site in a potential Source are provided. Then the basicformula of calculating expected magnitude and expected distance are developed. Several examples for calculating expected magnitude and expected distance in northern China are discussed. These results show that expected magnitude and expected distance are related not only to geometry of potential source and magnitude but also to the intensity of the site with certain exceeding probability.展开更多
During the financial crisis, the delayed recognition of credit losses on loans and other financial instruments was identified as a weakness in existing incurred loss model of impairment stated by International Account...During the financial crisis, the delayed recognition of credit losses on loans and other financial instruments was identified as a weakness in existing incurred loss model of impairment stated by International Accounting Standards （IAS） 39, because it is believed that this delay might generate pro-cyclical effects. In response to the recommendations of G20, Financial Crisis Advisory Group （FCAG）, and other international bodies, the International Accounting Standards Board （IASB） has undertaken, since 2009, as a part of the project to replace IAS 39, a project （partially shared with Financial Accounting Standards Board （FASB）） aimed at introducing an expected loss model of impairment. Within the scope of this subset project, the IASB has previously issued two exposure documents proposing models to account for expected credit losses： an exposure draft （ED） Financial Instrument： Amortized Cost and Impairment, published in November 2009, and a supplementary document （SD） Financial Instrument： Impairment, published jointly with the FASB in January 2011. However, neither of the two proposals received strong support from interested parties. Recently, the IASB, after the FASB＇s decision to withdraw from the joint project and to develop a separate expected credit loss model based on a single measurement approach consisting in the sole recognition of lifetime expected credit losses, published a third proposal--Ahe so-called expected credit losses model （ED/2013/3 Financial Instruments： Expected Credit Losses）.展开更多
The purpose of this paper is to consider the expected value of a discounted penalty due at ruin in the Erlang（2） risk process under constant interest force. An integro-differential equation satisfied by the expected...The purpose of this paper is to consider the expected value of a discounted penalty due at ruin in the Erlang（2） risk process under constant interest force. An integro-differential equation satisfied by the expected value and a second-order differential equation for the Laplace transform of the expected value are derived. In addition, the paper will present the recursive algorithm for the joint distribution of the surplus immediately before ruin and the deficit at ruin. Finally, by the differential equation, the defective renewal equation and the explicit expression for the expected value are given in the interest-free case.展开更多
基金funded by“National Natural Science Foundation of China”grant number[71872119]“Shanxi Provincial Government Major Decision-making Consulting Project”grant number[ZB20240114]The APC was funded by“Shanxi Provincial Government Major Decision-making Consulting Project”grant number[ZB20240114].
文摘Employees’innovative performance determines an organization’s innovation,which critically impacts its structural optimization and sustainability.Applying expectancy theory,we examined how and when the Pygmalion effect occurs in the relationship between leaders’expectations of innovation and employee innovative behavior.Our sample comprised 201 frontline employees(female=31.84%;mean age=41.48 years,SD=7.97 years)in a Chinese coal enterprise,who completed surveys on innovation expectations of leaders,expected positive performance outcomes,innovative self-efficacy and innovative behavior.The results revealed that employees’expected positive performance outcomes mediated the positive relationship between leaders’innovation expectations and their innovative behavior.Employees’innovative self-efficacy positively moderated the relationship between their expected positive performance outcomes and innovative behavior,with this relationship being stronger for employees with high innovative self-efficacy.Moreover,we validated the moderated mediation model.Findings suggest that leaders can stimulate employee innovative behavior through expressing expectations and they also need to consider the boundary conditions.
基金funded by the National Institute for Health Research (NIHR) Leicester Biomedical Research Centre (BRC)the Applied Research Collaborations East Midlands (ARC-EM)supported by a UKRI project grant (MR/T031816/1)。
文摘Background There is a lack of research examining the interplay between objectively measured physical activity volume and intensity with life expectancy.The purpose of the study was to investigate the interplay between objectively measured PA volume and intensity profiles with modeled life expectancy in women and men within the UK Biobank cohort study and interpret findings in relation to brisk walking.Methods Individuals from UK Biobank with wrist-worn accelerometer data were included.The average acceleration and intensity gradient were extracted to describe the physical activity volume and intensity profile.Mortality data were obtained from national registries.Adjusted life expectancies were estimated using parametric flexible survival models.Results 40,953(57.1%)women(median age=61.9 years)and 30,820(42.9%)men(63.1 years)were included.Over a median follow-up of 6.9 years,there were 1719(2.4%)deaths(733 in women;986 in men).At 60 years,life expectancy was progressively longer for higher physical activity volume and intensity profiles,reaching 95.6 years in women and 94.5 years in men at the 90th centile for both volume and intensity,corresponding to 3.4 additional years(95%confidence interval(95%CI):2.4-4.4)in women and 4.6 additional years(95%CI:3.6-5.6)in men compared to those at the 10th centiles.An additional 10-min or 30-min daily brisk walk was associated with 0.9(95%CI:0.5-1.3)and 1.4 years(95%CI:0.9-1.9)longer life expectancy,respectively,in inactive women;and 1.4 years(95%CI:1.0-1.8)and 2.5(95%CI:1.9-3.1)in inactive men.Conclusion Higher physical activity volumes were associated with longer life expectancy,with a higher physical activity intensity profile further adding to a longer life.Adding as little as a 10-min brisk walk to daily activity patterns may result in a meaningful benefit to life expectancy.
文摘In the new released article of the Journal of Sport and Health Science,Zaccardi et al.1 provide compelling evidence that engaging in higher volumes and intensities of physical activity(PA)increases life expectancy in older men and women enrolled in the UK Biobank study.The study included 30,820 men and 40,953 women with median ages of 63.1 years and 61.9 years,respectively.Study participants wore accelerometers to track their time and intensity of PA for 7 days at baseline.
文摘The repeated failures of any equipment or systems are modeled as a renewal process. The management needs an assessment of the number of future failures to allocate the resources needed for fast repairs. Based on the idea of expectation by conditioning, special Volterra-type integral equations are derived for general types of repairs, considering the length of repair and reduced degradation of the idle object. In addition to minimal repair and failure replacement, partial repairs are also discussed when the repair results in reduction of the number of future failures or decreases the effective age of the object. Numerical integration-based algorithm and simulation study are performed to solve the resulting integral equation. Since the geometry degradation in different dimensions of a rail track and controlling and maintaining defects are of importance, a numerical example using the rail industry data is conducted. Expected number of failures of different failure type modes in rail track is calculated within a two-year interval. Results show that within a two-year period, anticipated occurrences of cross level failures, surface failures, and DPI failures are 2.4, 3.8, and 5.8, respectively.
基金supported by Doctoral Scientific Research Starting Foundation of Jingdezhen Ceramic University(Grant No.102/01003002031)Re-accompanying Funding Project of Academic Achievements of Jingdezhen Ceramic University(Grant Nos.215/20506277,215/20506341)。
文摘The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the equivalent conditions of complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space.The results complement the corresponding results in probability space to those for sequences of independent,identically distributed random variables under sublinear expectation space.
文摘This study investigates the return dynamics,volatility structure,and risk characteristics of five representative S&P 500 stocks:Johnson&Johnson,Microsoft,NVIDIA,Coca-Cola,and Home Depot,using ARMA-GARCH models.Descriptive statistics and diagnostic tests confirm non-normality,negative skewness,fat tails,and volatility clustering,providing strong justification for conditional mean-variance modelling.Optimal model specifications are selected via the Bayesian Information Criterion,with EGARCH frameworks generally outperforming alternative GARCH variants in capturing asymmetric volatility responses.Rolling-window forecasts for 2024Q1 show that the models generate stable and reliable volatility predictions for low-volatility stocks(JNJ,KO),while performance is weaker for highly volatile stocks(NVDA),highlighting structural limitations under extreme market shifts.To evaluate risk management implications,one percent Value-at-Risk and expected shortfall were computed and backtested.Results indicated conservative tail-risk forecasts,with violation rates well within acceptable thresholds.Portfolio applications are further explored by constructing the Global Minimum Variance Portfolio(GMVP)and the Maximum Sharpe Ratio(Max SR)portfolio using rolling covariance estimates.Out-of-sample backtesting demonstrated that the GMVP delivered low volatility but modest returns,whereas the Max SR portfolio achieved significantly higher performance,consistent with the risk-return trade-off.Overall,the findings confirm that ARMA-GARCH models are effective tools for modelling conditional volatility and informing dynamic asset allocation.However,their limited adaptability to jump risk and nonlinear structural breaks underscores the need for more advanced modelling approaches in high-volatility environments.
基金funded by National Natural Science Foundation of China(grant No.52405255)Special Program of Huzhou(grant No.2023GZ05)+1 种基金Projects of Huzhou Science and Technology Correspondent(grant No.2023KT76)Guangdong Basic and Applied Basic Research Foundation(grant No.2025A1515010487)。
文摘Variable-fidelity(VF)surrogate models have received increasing attention in engineering design optimization as they can approximate expensive high-fidelity(HF)simulations with reduced computational power.A key challenge to building a VF model is devising an adaptive model updating strategy that jointly selects additional low-fidelity(LF)and/or HF samples.The additional samples must enhance the model accuracy while maximizing the computational efficiency.We propose ISMA-VFEEI,a global optimization framework that integrates an Improved Slime-Mould Algorithm(ISMA)and a Variable-Fidelity Expected Extension Improvement(VFEEI)learning function to construct a VF surrogate model efficiently.First,A cost-aware VFEEI function guides the adaptive LF/HF sampling by explicitly incorporating evaluation cost and existing sample proximity.Second,ISMA is employed to solve the resulting non-convex optimization problem and identify global optimal infill points for model enhancement.The efficacy of ISMA-VFEEI is demonstrated through six numerical benchmarks and one real-world engineering case study.The engineering case study of a high-speed railway Electric Multiple Unit(EMU),the optimization objective of a sanding device attained a minimum value of 1.546 using only 20 HF evaluations,outperforming all the compared methods.
文摘As an old Chinese saying goes,knowledge changes fate.An ordinary college student carries expectations of several generations of his or her family.Consequently,a vast majority of high school graduates applying for college prefer to choose colleges and majors with good employment prospects.Two years ago,facing hundreds of majors,I was caught in a dilemma.Law seemed appealing,as it could offer a high income and a worry-free life.
基金supported by Tehran University of Medical Sciences,Tehran,Iran(no.9711199007).
文摘Objective:The aim of this study was to investigate the health expectations(HEs)in patients with diabetes and the factors affecting it using an integrative systematic review.Methods:A comprehensive literature search was conducted in databases including PubMed,Scopus,Science Direct,Google Scholar,ProQuest,CINAHL,SID,Iran Doc,and Magiran without time limitation using related keywords.The systematic literature search was performed using a guide provided by York University.Results:From a total of 1883 articles,17 of them finally met the eligibility criteria.According to the findings of this study,HE of diabetic patients was included in four categories:“dynamism,”“consequentialism,”“comprehensive care,”and“access to facilities.”Also,these expectations can be influenced by various factors,including“developments in societies,”“changing the conditions of health care systems,”and“individual factors.”Conclusions:Health professionals should pay attention to the expectations of diabetic patients who are involved in complex disease conditions and consider meeting them as a key factor in providing patient-centered care,improving health outcomes,and patient satisfaction.
基金supported in part by the National Key Research and Development Program of China with Grant number 2021YFB2900502。
文摘In this paper,an index modulation(IM)aided uplink orthogonal time frequency space modulation(OTFS)structure for sparse code multiple access(SCMA)is proposed.To be more specific,the information bits are firstly partitioned for transmit antenna(TA)selection and sparse codeword mapping,respectively.Subsequently,the codewords deployed on the 2-dimensional(2D)delay-Doppler(DD)plane are transmitted by the selected TA,and the superimposed signals are jointly detected at the receiver.Furthermore,a low-complexity zero-embedded expectation propagation(ZE-EP)detector is conceived,where the codebooks are extended with zero vectors to reflect the silent indices.The simulation results demonstrate that the proposed IM-OTFS-SCMA system is capable of providing significant performance gain over the OTFS-SCMA counterpart.
基金This research received grant from 2022 Undergraduate Education and Teaching Research Project of Fujian Medical University(22028).
文摘Objective:This study aimed to investigate the learning expectations of undergraduate nursing students regarding the flipped Health Assessment course.Methods:This descriptive,qualitative study was conducted at a medical university in Fuzhou,Fujian Province,China.An interview outline was designed based on the core dimensions of Expectation Confirmation Theory(expectation sources,expectation content,and expectation importance).Thirty second-year undergraduate nursing students who had completed first-year basic medical courses and were about to take the flipped Health Assessment course were interviewed between June and July 2022.Interview data were analyzed using qualitative content analysis.Results:Five major themes and thirteen subthemes were identified.Theme 1 was expectation sourcesperceived learning difficulties from past experiences,which included four subthemes:insufficient autonomous learning ability,confusion regarding learning methods,insufficient engagement in learning,and low professional identity.Theme 2 included knowledge and information expectations,which comprised three subthemes:knowledge to improve professional competence,knowledge to enhance academic competitiveness,and knowledge to boost self-efficacy.Theme 3 comprised logical expectations and included two subthemes:flexible teaching methods and efficient instructional tools.Theme 4,pleasure expectations,included two subthemes:vivid teaching styles and diversified teaching evaluations.Theme 5 comprised professional value expectations and included two subthemes:teachers'responsible professional attitudes and gentle emotional support.Conclusion:Students'learning expectations originate from perceived learning difficulties,such as insufficient learning autonomy and engagement,confusion about learning methods,and a lack of professional identity.They showed various learning expectations for the flipped Health Assessment course,including knowledge and information,logic,pleasure,and professional value expectations.
文摘With the industrialization of agriculture and the advancement of medical care,human life expectancy has increased considerably and continues to rise steadily.This results in novel and unprecedented challenges,namely obesity and neurodegeneration.
文摘How do individuals adjust their savings and consumption behaviors in response to the combined effects of increased life expectancy and declining pension replacement rates?This study constructs a life-cycle model,using changes in conditional survival probabilities as a proxy for shifts in individual life expectancy,to examine consumption behavior under the dual backdrop of prolonged longevity and a gradual decline in pension replacement rates.The results suggest that changes in life expectancy and pension replacement rates together explain 8.9%to 10.2%of the observed decline in consumption in recent years,with both variables playing equally significant explanatory roles.Furthermore,we find that,to fully offset the negative impact of increased life expectancy on consumption,the pension replacement rate must reach at least 82%.These findings offer theoretical and policy implications for improving the quality of life in later years among enterprise employees in the context of population aging.
基金Supported by the Academic Achievement Re-cultivation Projects of Jingdezhen Ceramic University(Grant Nos.215/20506341215/20506277)the Doctoral Scientific Research Starting Foundation of Jingdezhen Ceramic University(Grant No.102/01003002031)。
文摘Assume that{a_(i),−∞<i<∞}is an absolutely summable sequence of real numbers.We establish the complete q-order moment convergence for the partial sums of moving average processes{X_(n)=Σ_(i=−∞)^(∞)a_(i)Y_(i+n),n≥1}under some proper conditions,where{Yi,-∞<i<∞}is a doubly infinite sequence of negatively dependent random variables under sub-linear expectations.These results extend and complement the relevant results in probability space.
基金supported by scientific research fund of Jiangxi Provincial Social Sciences“14th Five-Year Plan”(No.23SH05).
文摘This study investigated the relationship between parental cognitive ability and child logical reasoning ability,and the role of academic expectation and family environment in that relationship.Based on the 2020 China Family Panel Studies(CFPS)data,1491 children(girls ratio=53.78%;average grade=6.023 years,school grade standard deviation=1.825 years).Results following multiple regression model(OLS)show that the higher the parental cognitive ability,the higher the children’s logical reasoning ability.Secondly,parental academic expectation serves as a mediator between their cognitive ability and children’s logical reasoning ability for higher logical reasoning by children.Third,a possible family environment acts as a mediator in the relationship between parents’cognitive ability and children’s logical reasoning ability to be higher.We conclude from thesefindings that parents with high cognitive abilities can enhance their children’s logical reasoning skills not only by setting higher academic expectations,but also by cultivating a supportive family environment.Thesefindings imply a need for intervention to improve family quality of life to enhance children’s thinking abilities to optimize their academic learning.
基金Supported by National Natural Science Foundation of China (71171003, 71271003)Programming Fund Project of the Humanities and Social Sciences Research of the Ministry of Education of China (12YJA790041)+1 种基金Anhui Natural Science Foundation (090416225, 1208085MG116)Anhui Natural Science Foundation of Universities (KJ2010A037, KJ2010B026)
文摘This article studies optimal consumption-leisure, portfolio and retirement selection of an infinitely lived investor whose preference is formulated by a-maxmin expected CES utility which is to differentiate ambiguity and ambiguity attitude. Adopting the recursive multiple- priors utility and the technique of backward stochastic differential equations （BSDEs）, we transform the （^-maxmin expected CES utility into a classical expected CES utility under a new probability measure related to the degree of an investor＇s uncertainty. Our model investi- gates the optimal consumption-leisure-work selection, the optimal portfolio selection, and the optimal stopping problem. In this model, the investor is able to adjust her supply of labor flex- ibly above a certain minimum work-hour along with a retirement option. The problem can be analytically solved by using a variational inequality. And the optimal retirement time is given as the first time when her wealth exceeds a certain critical level. The optimal consumption-leisure and portfolio strategies before and after retirement are provided in closed forms. Finally, the distinctions of optimal consumption-leisure, portfolio and critical wealth level under ambiguity from those with no vagueness are discussed.
文摘Magnitude and distance of major potential source are needed in order to determine duration time of artificial ground motion and to determine the type of response spectrum (near field or far field) when using the seismic intensity zonation map. The magnitude probabilistic distribution function of seismic belt and the magnitude and space joint distribution function for given intensity of the site in a potential Source are provided. Then the basicformula of calculating expected magnitude and expected distance are developed. Several examples for calculating expected magnitude and expected distance in northern China are discussed. These results show that expected magnitude and expected distance are related not only to geometry of potential source and magnitude but also to the intensity of the site with certain exceeding probability.
文摘During the financial crisis, the delayed recognition of credit losses on loans and other financial instruments was identified as a weakness in existing incurred loss model of impairment stated by International Accounting Standards （IAS） 39, because it is believed that this delay might generate pro-cyclical effects. In response to the recommendations of G20, Financial Crisis Advisory Group （FCAG）, and other international bodies, the International Accounting Standards Board （IASB） has undertaken, since 2009, as a part of the project to replace IAS 39, a project （partially shared with Financial Accounting Standards Board （FASB）） aimed at introducing an expected loss model of impairment. Within the scope of this subset project, the IASB has previously issued two exposure documents proposing models to account for expected credit losses： an exposure draft （ED） Financial Instrument： Amortized Cost and Impairment, published in November 2009, and a supplementary document （SD） Financial Instrument： Impairment, published jointly with the FASB in January 2011. However, neither of the two proposals received strong support from interested parties. Recently, the IASB, after the FASB＇s decision to withdraw from the joint project and to develop a separate expected credit loss model based on a single measurement approach consisting in the sole recognition of lifetime expected credit losses, published a third proposal--Ahe so-called expected credit losses model （ED/2013/3 Financial Instruments： Expected Credit Losses）.
基金supported by the National Natural science Foundation of china(70271069)
文摘The purpose of this paper is to consider the expected value of a discounted penalty due at ruin in the Erlang（2） risk process under constant interest force. An integro-differential equation satisfied by the expected value and a second-order differential equation for the Laplace transform of the expected value are derived. In addition, the paper will present the recursive algorithm for the joint distribution of the surplus immediately before ruin and the deficit at ruin. Finally, by the differential equation, the defective renewal equation and the explicit expression for the expected value are given in the interest-free case.
