This paper considers the rational expectations model with multiplicative noise and input delay,where the system dynamics rely on the conditional expectations of future states.The main contribution is to obtain a suffi...This paper considers the rational expectations model with multiplicative noise and input delay,where the system dynamics rely on the conditional expectations of future states.The main contribution is to obtain a sufficient condition for the exact controllability of the rational expectations model.In particular,we derive a sufficient Gramian matrix condition and a rank condition for the delay-free case.The key is the solvability of the backward stochastic difference equations with input delay which is derived from the forward and backward stochastic system.展开更多
The neutron spectrum unfolding by Bonner sphere spectrometer(BSS) is considered a complex multidimensional model,which requires complex mathematical methods to solve the first kind of Fredholm integral equation. In or...The neutron spectrum unfolding by Bonner sphere spectrometer(BSS) is considered a complex multidimensional model,which requires complex mathematical methods to solve the first kind of Fredholm integral equation. In order to solve the problem of the maximum likelihood expectation maximization(MLEM) algorithm which is easy to suffer the pitfalls of local optima and the particle swarm optimization(PSO) algorithm which is easy to get unreasonable flight direction and step length of particles, which leads to the invalid iteration and affect efficiency and accuracy, an improved PSO-MLEM algorithm, combined of PSO and MLEM algorithm, is proposed for neutron spectrum unfolding. The dynamic acceleration factor is used to balance the ability of global and local search, and improves the convergence speed and accuracy of the algorithm. Firstly, the Monte Carlo method was used to simulated the BSS to obtain the response function and count rates of BSS. In the simulation of count rate, four reference spectra from the IAEA Technical Report Series No. 403 were used as input parameters of the Monte Carlo method. The PSO-MLEM algorithm was used to unfold the neutron spectrum of the simulated data and was verified by the difference of the unfolded spectrum to the reference spectrum. Finally, the 252Cf neutron source was measured by BSS, and the PSO-MLEM algorithm was used to unfold the experimental neutron spectrum.Compared with maximum entropy deconvolution(MAXED), PSO and MLEM algorithm, the PSO-MLEM algorithm has fewer parameters and automatically adjusts the dynamic acceleration factor to solve the problem of local optima. The convergence speed of the PSO-MLEM algorithm is 1.4 times and 3.1 times that of the MLEM and PSO algorithms. Compared with PSO, MLEM and MAXED, the correlation coefficients of PSO-MLEM algorithm are increased by 33.1%, 33.5% and 1.9%, and the relative mean errors are decreased by 98.2%, 97.8% and 67.4%.展开更多
This paper is a further elaboration of my model of the pathophysiology of major depressive disorder focusing on imbalances of glial-neuronal interactions in tripartite synapses and the glial network (syncytium). Basic...This paper is a further elaboration of my model of the pathophysiology of major depressive disorder focusing on imbalances of glial-neuronal interactions in tripartite synapses and the glial network (syncytium). Basically, it is proposed that the connexin proteins building gap junctions in the glial syncytium are underexpressed or dysfunctional in major depression, called syncytiopathy. As a compensatory effect the astrocytic receptors in tripartite synapses are overexpressed. This leads to protracted synaptic information processing because of a relative lack of neurotransmitter substances for the occupancy of astrocytic receptors. Based on a new biophysical formal description of astrocytic receptors as expectation variables it can be shown that the protracted processing of sensory information frustrate the full comprehension of the expected event, since it cannot be grasped in time. Moreover, expectation frustration may stress the glial syncytium aggravating memory impairment. This cyclic process of dysbalanced synaptic information processing is characterized as self-frustration of expectations explanatory for the main cognitive dysfunctions in major depression as slowing down processing speed, deficits in attention and working memory. The main result of the study is that patients with major depression cannot fully acknowledge the existence of an intended event.展开更多
There are a plethora of empirical pieces about employees’pro-environmental behaviors.However,the extant literature has either ignored or not fully examined various factors(e.g.,negative or positive non-green workplac...There are a plethora of empirical pieces about employees’pro-environmental behaviors.However,the extant literature has either ignored or not fully examined various factors(e.g.,negative or positive non-green workplace factors)that might affect employees’pro-environmental behaviors.Realizing these voids,the present paper proposes and tests a serial mediation model that examines the interrelationships of job insecurity,emotional exhaustion,met expectations,and proactive pro-environmental behavior.We used data gathered from hotel customer-contact employees with a time lag of one week and their direct supervisors in China.After presenting support for the psychometric properties of the measures via confirmatory analysis in LISREL 8.30,the abovementioned linkages were gauged using the PROCESS plug-in for statistical package for social sciences.The findings delineated support for the hypothesized associations.Specifically,emotional exhaustion and met expectations partly mediated the effect of job insecurity on proactive pro-environmental behavior.More importantly,emotional exhaustion and met expectations serially mediated the influence of job insecurity on proactive pro-environmental behavior.These findings have important theoretical implications as well as significant implications for diminishing job insecurity,managing emotional exhaustion,increasing met expectations,and enhancing ecofriendly behaviors.展开更多
Lost Horizon tells a story about Shangri-La,a paradise in the Orient.Throughout the construction of the Oriental image in the novel,it can be found that under its representation of being enslaved,driven,marginalized a...Lost Horizon tells a story about Shangri-La,a paradise in the Orient.Throughout the construction of the Oriental image in the novel,it can be found that under its representation of being enslaved,driven,marginalized and silenced,it implies a three-dimensional flow mechanism with multiple power-relationships interwoven between Orient and Occident,insiders and outsiders,“civilized”and“uncivilized”,male and female,etc.Driven by this mechanism,the Oriental image is integrated under a single abstract label,which has become a way for the Occident to re-understand,reconstruct and express itself after the war.展开更多
The Newton’s theory of universal gravitation is generalized. Significantly strong at short distances central interaction of bodies and particles is established in comparison with Newtonian. A connection is found with...The Newton’s theory of universal gravitation is generalized. Significantly strong at short distances central interaction of bodies and particles is established in comparison with Newtonian. A connection is found with Black Holes, with the horizon of events. Possibility of systematization of all Black Holes is shown. An illustration is given on the example of Black Hole S<sub>gr</sub>A*.展开更多
The movement of the Iron&Steelmaking(I&S)industry towards Net-Zero emissions and digitalized processes through disruptive,breakthrough technologies will be achieved through the use of Hydrogen.The biggest chal...The movement of the Iron&Steelmaking(I&S)industry towards Net-Zero emissions and digitalized processes through disruptive,breakthrough technologies will be achieved through the use of Hydrogen.The biggest challenge for the refractory industry is to continue to meet the performance expectations while,at the same time,moving to a more sustainable production direction.The complexity and urgency of these technological changes,highlighted by the European Green Deal,requires ambitious,international,interdisciplinary and intersectoral projects,bringing together institutes from across the global value chain,to carry out cutting edge research.The European Union,through its flagship doctoral training program,MSCA,has,and continues to support research and development as well as the promotion of the refractory industry in Europe.An introduction to two MSCA projects and some of the results achieved are highlighted within this article.展开更多
This study presents a kinematic calibration method for exoskeletal inertial motion capture (EI-MoCap) system with considering the random colored noise such as gyroscopic drift.In this method, the geometric parameters ...This study presents a kinematic calibration method for exoskeletal inertial motion capture (EI-MoCap) system with considering the random colored noise such as gyroscopic drift.In this method, the geometric parameters are calibrated by the traditional calibration method at first. Then, in order to calibrate the parameters affected by the random colored noise, the expectation maximization (EM) algorithm is introduced. Through the use of geometric parameters calibrated by the traditional calibration method, the iterations under the EM framework are decreased and the efficiency of the proposed method on embedded system is improved. The performance of the proposed kinematic calibration method is compared to the traditional calibration method. Furthermore, the feasibility of the proposed method is verified on the EI-MoCap system. The simulation and experiment demonstrate that the motion capture precision is significantly improved by 16.79%and 7.16%respectively in comparison to the traditional calibration method.展开更多
Pilots need to board the ship for pilotage,but there are risks or potential dangers in the transfer of pilot.The author reviewed the history of the development of pilot boats,analyzed the potential risks or dangers of...Pilots need to board the ship for pilotage,but there are risks or potential dangers in the transfer of pilot.The author reviewed the history of the development of pilot boats,analyzed the potential risks or dangers of transferring pilot,proposed that pilot boat shall have the function of ensuring the safety of pilot when embarking or disembarking the ships,some suggestions on the future design and manufacture of Chinese pilot boats are also given according to the advantages and disadvantages of domestic and foreign pilot boats.展开更多
Background:This study aimed to investigate the relationship between parental educational expectations and adolescent mental health problems,with academic pressure as a moderating variable.Methods:This study was based ...Background:This study aimed to investigate the relationship between parental educational expectations and adolescent mental health problems,with academic pressure as a moderating variable.Methods:This study was based on the baseline data of the China Education Panel Survey,which was collected within one school year during 2013–2014.It included 19,958 samples from seventh and ninth graders,who ranged from 11 to 18 years old.After removing missing values and conducting relevant data processing,the effective sample size for analysis was 16344.The OLS(Ordinary Least Squares)multiple linear regression analysis was used to examine the relationship between parental educational expectations,academic pressure,and adolescents’mental health problems.In addition,we established an interaction term between parents’educational expectations and academic pressure to investigate the moderating effect of academic stress.Results:The study found that adolescents whose parents had high educational expectations reported less mental health problems.(β=−0.195;p<0.001).Additionally,adolescents who had high academic pressure reported more mental health problems.(β=0.649;p<0.001).Furthermore,the study found that academic pressure had a significant moderating effect on the relationship between parental educational expectations and adolescents’mental health problems(β=0.082;p<0.001).Conclusion:Parental educational expectations had a close relationship with adolescents’mental health problems,and academic pressure moderated this relationship.For those adolescents with high levels of academic pressure,the association between high parental educational expectations and mental health problems became stronger.On the contrary,for those adolescents with low levels of academic pressure,the association between high parental educational expectations and mental health problems became weaker.These findings shed new light on how parental educational expectations affected adolescent mental health problems and had significant implications for their healthy development.展开更多
Objective:This study explores the interplay between job stress,job-related factors,work performance,and attitudes toward seeking professional psychological help among Vietnamese employees.Methods:A total of 374 employ...Objective:This study explores the interplay between job stress,job-related factors,work performance,and attitudes toward seeking professional psychological help among Vietnamese employees.Methods:A total of 374 employees in Vietnam were surveyed using random sampling and an online questionnaire from November 07 to November 28,2023.Demographic data and self-reported from three scales:The New Job Stress Scale(NJSS),Work Performance(WP),and Attitudes Toward Seeking Professional Psychological Help(ATSPPH_SF)were collected.Results:Significant variations were found across several variables,including forms of work,operating hours,education levels,monthly income,numbers of daily working hours,and the presence of a psychological counseling department within the company.Our analysis has highlighted direct relationships between key latent variables.Employees who were more open to seeking professional help tended to report higher levels of job stress.The negative relationship was found between job stress and attitudes toward seeking professional help.Additionally,work effort was positively associated with work quality.Moderation analyses revealed the influence of co-worker support on role expectation conflict and work effort,role expectation conflict and work-life balance,as well as interactions between role expectation conflict and attitudes needed toward seeking professional help.Mediation analyses showed that work effort mediated relationships between openness to seeking professional help,co-worker support,work-life balance,role expectation conflict,and work quality.Attitudes toward seeking professional help also mediated relationships between work-life balance,job stress,and work quality.Conclusion:The study highlights the complex dynamics surrounding job stress,job-related factors,work performance,and attitudes toward seeking professional psychological help among Vietnamese employees.It highlights the importance of addressing help-seeking barriers,promoting work engagement,and fostering healthy work-life balance for employee well-being and productivity.Further research across diverse contexts and interventions is needed.展开更多
In this article, we address the solution of the Einstein’s equations in the vacuum region surrounding a spherically symmetric mass distribution. There are two different types of mathematical solutions, depending on t...In this article, we address the solution of the Einstein’s equations in the vacuum region surrounding a spherically symmetric mass distribution. There are two different types of mathematical solutions, depending on the value of a constant of integration. These two types of solutions are analysed from a physical point of view. The comparison with the linear theory limit is also considered. This leads to a new solution, different from the well known one. If one considers the observational data in the weak field limit this new solution is in agreement with the available data. While the traditional Schwarzschild solution is characterized by a horizon at r=2GM/c2, no horizon exists in this new solution.展开更多
The"horizon of expectations"is the standards readers use to judge literary texts in any given period. These standards will help the reader decide the genre of a literary work. It will also, in a more general...The"horizon of expectations"is the standards readers use to judge literary texts in any given period. These standards will help the reader decide the genre of a literary work. It will also, in a more general way, cover what is to be regarded as poetic or literary as opposed to unpoetic or non-literary uses of languages.展开更多
The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition...The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition can be influenced.For addressing this issue,a method for extracting ship targets with overlaps via the expectation maximization(EM)algorithm is pro-posed.First,the scatterers of ship targets are obtained via the target detection technique.Then,the EM algorithm is applied to extract the scatterers of a single ship target with a single IPP.Afterwards,a novel image amplitude estimation approach is pro-posed,with which the radar image of a single target with a sin-gle IPP can be generated.The proposed method can accom-plish IPP selection and targets separation in the image domain,which can improve the image quality and reserve the target information most possibly.Results of simulated and real mea-sured data demonstrate the effectiveness of the proposed method.展开更多
The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regressi...The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regression(GPR)model based on Conditional Likelihood Lower Bound Search(CLLBS)to optimize the design of the generator,which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search method.Taking the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an example.Firstly,this method uses the elementary effect analysis to choose the sensitive variables,combining the evolutionary algorithm to design the super Latin cube sampling plan;Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data.A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established,which combined the chi-square test to optimize the accuracy of the model globally.Secondly,after the model reaches the accuracy,the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a constraint.Last,the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation(CEI)optimization method based on the re-interpolation model,which cross-validated the optimization results of the Gaussian process regression model.The above method increase the efficiency of generator by 0.76%and 0.5%respectively;And this method can be used for rapid modeling and multi-objective optimization of generator systems.展开更多
A greenhouse experiment was conducted involving intact fragipan soil cores of 50 cm thickness after removing the topsoil horizons. The cores were maintained in moist condition throughout the experiment and received se...A greenhouse experiment was conducted involving intact fragipan soil cores of 50 cm thickness after removing the topsoil horizons. The cores were maintained in moist condition throughout the experiment and received several treatments with various amendments for different periods ranging from 9 to 17 months. The amendments included annual ryegrass or Festulolium residues, powder limestone and various humate compounds alone or in combination with the grass residues. The results suggested a significant effect of ryegrass and Festulolium in reducing penetration resistance into the top 10 cm of the fragipan within 9 - 17 months, particularly when used in combination with certain humate materials such as Leonardite. Apparently, this is the result of the release of certain soluble organic compounds from the plant residues or the humate amendments that increase the solubility of Si and Al associated with the fragipan brittleness, thus decreasing the density of the compacted fragipan material.展开更多
The Chinese economy continued to rebound and made solid progress in 2023,despite the complex international situation and numerous risks and challenges.The accelerated economic structural transformation and upgrade,cou...The Chinese economy continued to rebound and made solid progress in 2023,despite the complex international situation and numerous risks and challenges.The accelerated economic structural transformation and upgrade,coupled with increasing economic resilience,has resulted in various highlights.展开更多
How well is FOCAC meeting Africa’s aspirations for development?The idea of establishing the Forum on China-Africa Cooperation(FOCAC)in 2000 initially came from African countries,eager to coordinate and manage their r...How well is FOCAC meeting Africa’s aspirations for development?The idea of establishing the Forum on China-Africa Cooperation(FOCAC)in 2000 initially came from African countries,eager to coordinate and manage their relationship with China.展开更多
Nanomaterials are one of the research and development hotspots in the field of cutting-edge new materials,and also an important strategic emerging industry.Magnetic nanomaterials have broad application prospects in fi...Nanomaterials are one of the research and development hotspots in the field of cutting-edge new materials,and also an important strategic emerging industry.Magnetic nanomaterials have broad application prospects in fields such as chemical engineering,new materials,electronic information,and biomedicine.This article introduces the application progress and preparation methods of magnetic nanomaterials,and puts forward suggestions for further optimizing the preparation process of magnetic nanomaterials and developing new magnetic materials with better performance.展开更多
基金supported by the National Natural Science Foundation of China under Grants 61821004,62250056,62350710214,U23A20325,62350055the Natural Science Foundation of Shandong Province,China(ZR2021ZD14,ZR2021JQ24)+2 种基金High-level Talent Team Project of Qingdao West Coast New Area,China(RCTD-JC-2019-05)Key Research and Development Program of Shandong Province,China(2020CXGC01208)Science and Technology Project of Qingdao West Coast New Area,China(2019-32,2020-20,2020-1-4).
文摘This paper considers the rational expectations model with multiplicative noise and input delay,where the system dynamics rely on the conditional expectations of future states.The main contribution is to obtain a sufficient condition for the exact controllability of the rational expectations model.In particular,we derive a sufficient Gramian matrix condition and a rank condition for the delay-free case.The key is the solvability of the backward stochastic difference equations with input delay which is derived from the forward and backward stochastic system.
基金supported by the National Natural science Foundation of China (No. 42127807)the Sichuan Science and Technology Program (No. 2020YJ0334)the Sichuan Science and Technology Breeding Program (No. 2022041)。
文摘The neutron spectrum unfolding by Bonner sphere spectrometer(BSS) is considered a complex multidimensional model,which requires complex mathematical methods to solve the first kind of Fredholm integral equation. In order to solve the problem of the maximum likelihood expectation maximization(MLEM) algorithm which is easy to suffer the pitfalls of local optima and the particle swarm optimization(PSO) algorithm which is easy to get unreasonable flight direction and step length of particles, which leads to the invalid iteration and affect efficiency and accuracy, an improved PSO-MLEM algorithm, combined of PSO and MLEM algorithm, is proposed for neutron spectrum unfolding. The dynamic acceleration factor is used to balance the ability of global and local search, and improves the convergence speed and accuracy of the algorithm. Firstly, the Monte Carlo method was used to simulated the BSS to obtain the response function and count rates of BSS. In the simulation of count rate, four reference spectra from the IAEA Technical Report Series No. 403 were used as input parameters of the Monte Carlo method. The PSO-MLEM algorithm was used to unfold the neutron spectrum of the simulated data and was verified by the difference of the unfolded spectrum to the reference spectrum. Finally, the 252Cf neutron source was measured by BSS, and the PSO-MLEM algorithm was used to unfold the experimental neutron spectrum.Compared with maximum entropy deconvolution(MAXED), PSO and MLEM algorithm, the PSO-MLEM algorithm has fewer parameters and automatically adjusts the dynamic acceleration factor to solve the problem of local optima. The convergence speed of the PSO-MLEM algorithm is 1.4 times and 3.1 times that of the MLEM and PSO algorithms. Compared with PSO, MLEM and MAXED, the correlation coefficients of PSO-MLEM algorithm are increased by 33.1%, 33.5% and 1.9%, and the relative mean errors are decreased by 98.2%, 97.8% and 67.4%.
文摘This paper is a further elaboration of my model of the pathophysiology of major depressive disorder focusing on imbalances of glial-neuronal interactions in tripartite synapses and the glial network (syncytium). Basically, it is proposed that the connexin proteins building gap junctions in the glial syncytium are underexpressed or dysfunctional in major depression, called syncytiopathy. As a compensatory effect the astrocytic receptors in tripartite synapses are overexpressed. This leads to protracted synaptic information processing because of a relative lack of neurotransmitter substances for the occupancy of astrocytic receptors. Based on a new biophysical formal description of astrocytic receptors as expectation variables it can be shown that the protracted processing of sensory information frustrate the full comprehension of the expected event, since it cannot be grasped in time. Moreover, expectation frustration may stress the glial syncytium aggravating memory impairment. This cyclic process of dysbalanced synaptic information processing is characterized as self-frustration of expectations explanatory for the main cognitive dysfunctions in major depression as slowing down processing speed, deficits in attention and working memory. The main result of the study is that patients with major depression cannot fully acknowledge the existence of an intended event.
文摘There are a plethora of empirical pieces about employees’pro-environmental behaviors.However,the extant literature has either ignored or not fully examined various factors(e.g.,negative or positive non-green workplace factors)that might affect employees’pro-environmental behaviors.Realizing these voids,the present paper proposes and tests a serial mediation model that examines the interrelationships of job insecurity,emotional exhaustion,met expectations,and proactive pro-environmental behavior.We used data gathered from hotel customer-contact employees with a time lag of one week and their direct supervisors in China.After presenting support for the psychometric properties of the measures via confirmatory analysis in LISREL 8.30,the abovementioned linkages were gauged using the PROCESS plug-in for statistical package for social sciences.The findings delineated support for the hypothesized associations.Specifically,emotional exhaustion and met expectations partly mediated the effect of job insecurity on proactive pro-environmental behavior.More importantly,emotional exhaustion and met expectations serially mediated the influence of job insecurity on proactive pro-environmental behavior.These findings have important theoretical implications as well as significant implications for diminishing job insecurity,managing emotional exhaustion,increasing met expectations,and enhancing ecofriendly behaviors.
文摘Lost Horizon tells a story about Shangri-La,a paradise in the Orient.Throughout the construction of the Oriental image in the novel,it can be found that under its representation of being enslaved,driven,marginalized and silenced,it implies a three-dimensional flow mechanism with multiple power-relationships interwoven between Orient and Occident,insiders and outsiders,“civilized”and“uncivilized”,male and female,etc.Driven by this mechanism,the Oriental image is integrated under a single abstract label,which has become a way for the Occident to re-understand,reconstruct and express itself after the war.
文摘The Newton’s theory of universal gravitation is generalized. Significantly strong at short distances central interaction of bodies and particles is established in comparison with Newtonian. A connection is found with Black Holes, with the horizon of events. Possibility of systematization of all Black Holes is shown. An illustration is given on the example of Black Hole S<sub>gr</sub>A*.
基金the European Union's Horizon 2020 research and innovation program under grant agreement No.764987.The CESAREF project has received funding from the European Union's Horizon Europe research and innovation programunder grant agreement No.101072625.
文摘The movement of the Iron&Steelmaking(I&S)industry towards Net-Zero emissions and digitalized processes through disruptive,breakthrough technologies will be achieved through the use of Hydrogen.The biggest challenge for the refractory industry is to continue to meet the performance expectations while,at the same time,moving to a more sustainable production direction.The complexity and urgency of these technological changes,highlighted by the European Green Deal,requires ambitious,international,interdisciplinary and intersectoral projects,bringing together institutes from across the global value chain,to carry out cutting edge research.The European Union,through its flagship doctoral training program,MSCA,has,and continues to support research and development as well as the promotion of the refractory industry in Europe.An introduction to two MSCA projects and some of the results achieved are highlighted within this article.
基金supported by the National Natural Science Foundation of China (61503392)。
文摘This study presents a kinematic calibration method for exoskeletal inertial motion capture (EI-MoCap) system with considering the random colored noise such as gyroscopic drift.In this method, the geometric parameters are calibrated by the traditional calibration method at first. Then, in order to calibrate the parameters affected by the random colored noise, the expectation maximization (EM) algorithm is introduced. Through the use of geometric parameters calibrated by the traditional calibration method, the iterations under the EM framework are decreased and the efficiency of the proposed method on embedded system is improved. The performance of the proposed kinematic calibration method is compared to the traditional calibration method. Furthermore, the feasibility of the proposed method is verified on the EI-MoCap system. The simulation and experiment demonstrate that the motion capture precision is significantly improved by 16.79%and 7.16%respectively in comparison to the traditional calibration method.
文摘Pilots need to board the ship for pilotage,but there are risks or potential dangers in the transfer of pilot.The author reviewed the history of the development of pilot boats,analyzed the potential risks or dangers of transferring pilot,proposed that pilot boat shall have the function of ensuring the safety of pilot when embarking or disembarking the ships,some suggestions on the future design and manufacture of Chinese pilot boats are also given according to the advantages and disadvantages of domestic and foreign pilot boats.
基金the National Planning Office of Philosophy and Social Science,China (Grant Numbers 18ZDA133 & 23BSH105)ChinaAssociation of Higher Education (Grant Number 23LH0418).
文摘Background:This study aimed to investigate the relationship between parental educational expectations and adolescent mental health problems,with academic pressure as a moderating variable.Methods:This study was based on the baseline data of the China Education Panel Survey,which was collected within one school year during 2013–2014.It included 19,958 samples from seventh and ninth graders,who ranged from 11 to 18 years old.After removing missing values and conducting relevant data processing,the effective sample size for analysis was 16344.The OLS(Ordinary Least Squares)multiple linear regression analysis was used to examine the relationship between parental educational expectations,academic pressure,and adolescents’mental health problems.In addition,we established an interaction term between parents’educational expectations and academic pressure to investigate the moderating effect of academic stress.Results:The study found that adolescents whose parents had high educational expectations reported less mental health problems.(β=−0.195;p<0.001).Additionally,adolescents who had high academic pressure reported more mental health problems.(β=0.649;p<0.001).Furthermore,the study found that academic pressure had a significant moderating effect on the relationship between parental educational expectations and adolescents’mental health problems(β=0.082;p<0.001).Conclusion:Parental educational expectations had a close relationship with adolescents’mental health problems,and academic pressure moderated this relationship.For those adolescents with high levels of academic pressure,the association between high parental educational expectations and mental health problems became stronger.On the contrary,for those adolescents with low levels of academic pressure,the association between high parental educational expectations and mental health problems became weaker.These findings shed new light on how parental educational expectations affected adolescent mental health problems and had significant implications for their healthy development.
文摘Objective:This study explores the interplay between job stress,job-related factors,work performance,and attitudes toward seeking professional psychological help among Vietnamese employees.Methods:A total of 374 employees in Vietnam were surveyed using random sampling and an online questionnaire from November 07 to November 28,2023.Demographic data and self-reported from three scales:The New Job Stress Scale(NJSS),Work Performance(WP),and Attitudes Toward Seeking Professional Psychological Help(ATSPPH_SF)were collected.Results:Significant variations were found across several variables,including forms of work,operating hours,education levels,monthly income,numbers of daily working hours,and the presence of a psychological counseling department within the company.Our analysis has highlighted direct relationships between key latent variables.Employees who were more open to seeking professional help tended to report higher levels of job stress.The negative relationship was found between job stress and attitudes toward seeking professional help.Additionally,work effort was positively associated with work quality.Moderation analyses revealed the influence of co-worker support on role expectation conflict and work effort,role expectation conflict and work-life balance,as well as interactions between role expectation conflict and attitudes needed toward seeking professional help.Mediation analyses showed that work effort mediated relationships between openness to seeking professional help,co-worker support,work-life balance,role expectation conflict,and work quality.Attitudes toward seeking professional help also mediated relationships between work-life balance,job stress,and work quality.Conclusion:The study highlights the complex dynamics surrounding job stress,job-related factors,work performance,and attitudes toward seeking professional psychological help among Vietnamese employees.It highlights the importance of addressing help-seeking barriers,promoting work engagement,and fostering healthy work-life balance for employee well-being and productivity.Further research across diverse contexts and interventions is needed.
文摘In this article, we address the solution of the Einstein’s equations in the vacuum region surrounding a spherically symmetric mass distribution. There are two different types of mathematical solutions, depending on the value of a constant of integration. These two types of solutions are analysed from a physical point of view. The comparison with the linear theory limit is also considered. This leads to a new solution, different from the well known one. If one considers the observational data in the weak field limit this new solution is in agreement with the available data. While the traditional Schwarzschild solution is characterized by a horizon at r=2GM/c2, no horizon exists in this new solution.
文摘The"horizon of expectations"is the standards readers use to judge literary texts in any given period. These standards will help the reader decide the genre of a literary work. It will also, in a more general way, cover what is to be regarded as poetic or literary as opposed to unpoetic or non-literary uses of languages.
基金This work was supported by the National Science Fund for Distinguished Young Scholars(62325104).
文摘The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition can be influenced.For addressing this issue,a method for extracting ship targets with overlaps via the expectation maximization(EM)algorithm is pro-posed.First,the scatterers of ship targets are obtained via the target detection technique.Then,the EM algorithm is applied to extract the scatterers of a single ship target with a single IPP.Afterwards,a novel image amplitude estimation approach is pro-posed,with which the radar image of a single target with a sin-gle IPP can be generated.The proposed method can accom-plish IPP selection and targets separation in the image domain,which can improve the image quality and reserve the target information most possibly.Results of simulated and real mea-sured data demonstrate the effectiveness of the proposed method.
基金supported in part by the National Key Research and Development Program of China(2019YFB1503700)the Hunan Natural Science Foundation-Science and Education Joint Project(2019JJ70063)。
文摘The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regression(GPR)model based on Conditional Likelihood Lower Bound Search(CLLBS)to optimize the design of the generator,which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search method.Taking the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an example.Firstly,this method uses the elementary effect analysis to choose the sensitive variables,combining the evolutionary algorithm to design the super Latin cube sampling plan;Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data.A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established,which combined the chi-square test to optimize the accuracy of the model globally.Secondly,after the model reaches the accuracy,the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a constraint.Last,the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation(CEI)optimization method based on the re-interpolation model,which cross-validated the optimization results of the Gaussian process regression model.The above method increase the efficiency of generator by 0.76%and 0.5%respectively;And this method can be used for rapid modeling and multi-objective optimization of generator systems.
文摘A greenhouse experiment was conducted involving intact fragipan soil cores of 50 cm thickness after removing the topsoil horizons. The cores were maintained in moist condition throughout the experiment and received several treatments with various amendments for different periods ranging from 9 to 17 months. The amendments included annual ryegrass or Festulolium residues, powder limestone and various humate compounds alone or in combination with the grass residues. The results suggested a significant effect of ryegrass and Festulolium in reducing penetration resistance into the top 10 cm of the fragipan within 9 - 17 months, particularly when used in combination with certain humate materials such as Leonardite. Apparently, this is the result of the release of certain soluble organic compounds from the plant residues or the humate amendments that increase the solubility of Si and Al associated with the fragipan brittleness, thus decreasing the density of the compacted fragipan material.
文摘The Chinese economy continued to rebound and made solid progress in 2023,despite the complex international situation and numerous risks and challenges.The accelerated economic structural transformation and upgrade,coupled with increasing economic resilience,has resulted in various highlights.
文摘How well is FOCAC meeting Africa’s aspirations for development?The idea of establishing the Forum on China-Africa Cooperation(FOCAC)in 2000 initially came from African countries,eager to coordinate and manage their relationship with China.
文摘Nanomaterials are one of the research and development hotspots in the field of cutting-edge new materials,and also an important strategic emerging industry.Magnetic nanomaterials have broad application prospects in fields such as chemical engineering,new materials,electronic information,and biomedicine.This article introduces the application progress and preparation methods of magnetic nanomaterials,and puts forward suggestions for further optimizing the preparation process of magnetic nanomaterials and developing new magnetic materials with better performance.