This study aimed to explore how core self-evaluations and gender influence interpersonal adjustment and depression risk.Participants were 1748 college students(female=59.73%,male=40.27%,mean age=18.71 years,SD=0.78 yea...This study aimed to explore how core self-evaluations and gender influence interpersonal adjustment and depression risk.Participants were 1748 college students(female=59.73%,male=40.27%,mean age=18.71 years,SD=0.78 years).The students completed the Interpersonal Adjustment Scale for College Students,Center for Epidemiological Studies Depression Scale,and Core Self-evaluation Scale.The results of Linear regression and mediated moderated effects modeling revealed that college students with higher interpersonal adjustment and core self-evaluation scores were at lower risk for depression.Core self-evaluation mediated the relationship between interpersonal adjustment and depression in college students for lower risk for depression.Gender moderated the relationship between interpersonal adjustment and core self-evaluation in college students for higher risk for depression in female students.From thesefindings,we conclude that interpersonal adjustment and core self-evaluation are significant for screening depression risk college students.Moreover,female students may benefit from targeted interventions aimed at their interpersonal adjustment for reducing their risk of depression.展开更多
Internet gaming disorder(IGD)among junior high school students is an increasingly prominent mental health concern.It is important to look for influences behind internet gaming disorder tendency(IGDT)in the junior high...Internet gaming disorder(IGD)among junior high school students is an increasingly prominent mental health concern.It is important to look for influences behind internet gaming disorder tendency(IGDT)in the junior high school student population.The present study aimed to reveal the explanatory mechanisms underlying the association between parental psychological control(PPC)and internet gaming disorder tendency among junior high school students by testing the mediating role of core self-evaluation(CSE)and the moderating role of intentional self-regulation(ISR).Participants in present study were 735 Chinese junior high school students who completed offline self-report questionnaires on parental psychological control,core self-evaluation,intentional self-regulation,and Internet gaming disorder tendency.Analyses were conducted via mediation and moderated mediation.The results showed that:(1)Parental psychological control was positively related to junior high school students’Internet gaming disorder tendency.Core self-evaluation,and intentional self-regulation were negatively related to junior high school students’Internet gaming disorder tendency,respectively.(2)Core self-evaluation partially mediated the relationship between parental psychological control and junior high school students’Internet gaming disorder tendency.(3)Intentional self-regulation moderated the association between parental psychological control and Internet gaming disorder tendency,as well as the relationships between parental psychological control and core self-evaluation and core self-evaluation and Internet gaming disorder tendency in the mediated model.Based on these findings,we believe that there is a need to weaken parental psychological control,strengthen junior high school students’core self-evaluation and intentional self-regulation,and to recognize the important role of parents as well as their children’s personal positive traits in the healthy development of junior high school students.展开更多
The present study discusses the relationship among Chinese adolescents’parental involvement,core self-evaluation,and school adaptation.The Parental Involvement Behavior Questionnaire,Core Self-Evaluations Scale(CSES)...The present study discusses the relationship among Chinese adolescents’parental involvement,core self-evaluation,and school adaptation.The Parental Involvement Behavior Questionnaire,Core Self-Evaluations Scale(CSES),and the School Adaptation Inventory were used to survey 1258 Chinese middle school students.The results showed that adolescents’school adaptation was significantly positively correlated with parental involvement and core self-evaluation.Furthermore,parental involvement and core self-evaluation were positively correlated.Mediation analysis found that core self-evaluation had partially mediated the relationship between adolescents’parental involvement and school adaption.Parental involvement could directly affect adolescents’school adaptation and indirectly affect school adaptation through the mediating effect of core self-evaluation.The present study results suggested that parents and educators could improve adolescents’school adaptation by increasing parental involvement and enhancing the adolescents’core self-evaluation.展开更多
This study aimed to investigate the link between the exposure to intimate partner violence(IPV),core self-evaluations(CSE),and psychological adaptation of Chinese adolescents,through analysis of the results from the S...This study aimed to investigate the link between the exposure to intimate partner violence(IPV),core self-evaluations(CSE),and psychological adaptation of Chinese adolescents,through analysis of the results from the Survey of Children’s Exposure to Domestic Violence Scale,Core Self-Evaluations Scale,and Strengths and Difficulties Questionnaire,involving a total of 597 Chinese middle school students.It is indicated that the exposure to IPV is positively correlated with lower levels of psychological adaptation and CSE,and CSE is positively correlated with higher levels of psychological adaptation.Mediation analysis revealed that CSE partially mediated the association between the exposure to IPV and psychological adaptation.These results suggest that educators and parents should help adolescents tackle their emotional and behavioral problems by reducing the risk of IPV exposure and increasing their CSE.展开更多
The rapid development of the internet has led to the rise of social networking sites,which have impacted the psychological health and social adaptation of college students.Existing research shows that the intensity an...The rapid development of the internet has led to the rise of social networking sites,which have impacted the psychological health and social adaptation of college students.Existing research shows that the intensity and patterns of social networking site use are closely related to adolescents’core self-evaluations,with perceived social support playing a mediating role in this relationship.This study,based on a questionnaire survey of 231 college students with an average age of 19.5,reveals the intrinsic connection between social networking site use and core self-evaluations.The findings indicate that the intensity and pattern of use significantly affect self-evaluations,and perceived social support partially mediates this relationship.展开更多
Background:Social anxiety is prevalent among adolescents and severely impacts their mental health and social functioning.This study aims to explore the underlying mechanisms and subgroup differences in adolescent soci...Background:Social anxiety is prevalent among adolescents and severely impacts their mental health and social functioning.This study aims to explore the underlying mechanisms and subgroup differences in adolescent social anxiety to provide a theoretical basis for targeted interventions.Methods:3025 Chinese adolescents(Meanage=13.91±1.60 years;47%male)completed self-report measures of physical activity,core self-evaluation,and social anxiety.Variable-centered analyses employed PROCESS Model 4 with 5000 bootstrap samples;covariates were gender,grade,and place of residence.Person-centered analyses used latent profile analysis in Mplus 8.3 to identify subgroups based on social anxiety item profiles.Results:Variable-centered analyses showed that physical activity had a significant negative association with social anxiety(β=−0.224,p<0.001)and a significant positive association with core self-evaluation(β=0.471,p<0.001);core self-evaluation partially mediated this relationship,accounting for 30%of the total effect.Person-centered analyses revealed an optimal two-profile solution:a low social anxiety profile(89.6%)and a high social anxiety profile(10.4%).The high social anxiety profile reported significantly lower physical activity and lower core self-evaluation than the low social anxiety profile.Conclusions:This study integrates variable-centered and person-centered evidence,identifies physical activity and core self-evaluation as key modifiable factors in reducing social anxiety,providing a theoretical basis for targeted and differentiated interventions.展开更多
Informed by implicit leadership theories, this study investigates contemporary Chinese employees' preferences for paternalistic leadership (including three components: moral leadership, benevolent leadership and au...Informed by implicit leadership theories, this study investigates contemporary Chinese employees' preferences for paternalistic leadership (including three components: moral leadership, benevolent leadership and authoritarian leadership) and transformational leadership. It further examines the relationship between power distance orientation, core self-evaluation (CSE) and leadership preferences. The study finds that contemporary Chinese employees most prefer moral leadership, but are also highly receptive to transformational leadership. They prefer authoritarian leadership least. Moreover, preferences for authoritarian leadership are predicated on followers' power distance orientation. However, the opposite is true for moral leadership. CSE is positively related to followers' preference for authoritarian leadership, benevolent leadership and transformational leadership, but not except for moral leadership. A positive interaction effect is found between power distance orientation and CSE with regard to authoritarian leadership preference. The theoretical and practical implications of the findings are discussed.展开更多
This study aims to examine the relationship between authentic leadership and employee proactive behavior. Based on self-determination theory, we argue that such a relationship is sequentially mediated by psychological...This study aims to examine the relationship between authentic leadership and employee proactive behavior. Based on self-determination theory, we argue that such a relationship is sequentially mediated by psychological empowerment and core self-evaluations. In addition, political skill plays a moderating role in the third stage. These hypotheses are validated by a sample of 65 leaders and 275 subordinates from two private enterprises in China's Mainland. Results show that authentic leadership Clime I) influences employees' proactive behavior Clime 3) through the psychological empowerment (Time I) and core self-evaluations of employees (Time 2), and the relationship between core self-evaluations and proactive behavior is positively moderated by employees' political skill. In addition, bootstrapping results also verify the moderating role played by employees' political skill in the indirect relationship between authentic leadership and proactive behavior through core self-evaluations. Theoretical and managerial implications are further discussed in the light of these findings.展开更多
Deep tight reservoirs exhibit complex stress and seepage fields due to varying pore structures,thus the seepage characteristics are significant for enhancing oil production.This study conducted triaxial compression an...Deep tight reservoirs exhibit complex stress and seepage fields due to varying pore structures,thus the seepage characteristics are significant for enhancing oil production.This study conducted triaxial compression and permeability tests to investigate the mechanical and seepage properties of tight sandstone.A digital core of tight sandstone was built using Computed Tomography(CT)scanning,which was divided into matrix and pore phases by a pore equivalent diameter threshold.A fluid-solid coupling model was established to investigate the seepage characteristics at micro-scale.The results showed that increasing the confining pressure decreased porosity,permeability,and flow velocity,with the pore phase becoming the dominant seepage channel.Cracks and large pores closed first under increasing pressure,resulted in a steep drop in permeability.However,permeability slightly decreased under high confining pressure,which followed a first-order exponential function.Flow velocity increased with seepage pressure.And the damage mainly occurred in stress-concentration regions under low seepage pressure.Seepage behavior followed linear Darcy flow,the damage emerged at seepage entrances under high pressure,which decreased rock elastic modulus and significantly increased permeability.展开更多
Research on the mechanical–electrical properties is crucial for designing and preparing high-temperature superconducting(HTS)cables.Various winding core structures can influence the mechanical–electrical behavior of...Research on the mechanical–electrical properties is crucial for designing and preparing high-temperature superconducting(HTS)cables.Various winding core structures can influence the mechanical–electrical behavior of cables,but the impact of alterations in the winding core structure on the mechanical–electrical behavior of superconducting cables remains unclear.This paper presents a 3D finite element model to predict the performance of three cables with different core structures when subjected to transverse compression and axial tension.The three cables analyzed are CORC(conductor-on-round-core),CORT(conductor-on-round-tube),and HFRC(conductor-on-spiral-tube).A parametric analysis is carried out by varying the core diameter and inner-to-outer diameter ratio.Results indicate that the CORT cable demonstrates better performance in transverse compression compared to the CORC cable,aligning with experimental data.Among the three cables,the HFRC cables exhibit the weakest resistance to transverse deformation.However,the HFRC cable demonstrates superior tensile deformation resistance compared to the CORT cable,provided that the transverse compression properties are maintained.Finite element results also show that the optimum inner-to-outer diameter ratios for achieving the best transverse compression performance are approximately 0.8 for CORT cables and 0.6 for HFRC cables.Meanwhile,the study explores the effect of structural changes in HTS cable winding cores on their electromagnetic properties.It recommends utilizing small tape gaps,lower frequencies,and spiral core construction to minimize eddy losses.The findings presented in this paper offer valuable insights for the commercialization and practical manufacturing of HTS cables.展开更多
The application of liquid core reduction(LCR)technology in thin slab continuous casting can refine the internal microstruc-tures of slabs and improve their production efficiency.To avoid crack risks caused by large de...The application of liquid core reduction(LCR)technology in thin slab continuous casting can refine the internal microstruc-tures of slabs and improve their production efficiency.To avoid crack risks caused by large deformation during the LCR process and to minimize the thickness of the slab in bending segments,the maximum theoretical reduction amount and the corresponding reduction scheme for the LCR process must be determined.With SPA-H weathering steel as a specific research steel grade,the distributions of tem-perature and deformation fields of a slab with the LCR process were analyzed using a three-dimensional thermal-mechanical finite ele-ment model.High-temperature tensile tests were designed to determine the critical strain of corner crack propagation and intermediate crack initiation with various strain rates and temperatures,and a prediction model of the critical strain for two typical cracks,combining the effects of strain rate and temperature,was proposed by incorporating the Zener-Hollomon parameter.The crack risks with different LCR schemes were calculated using the crack risk prediction model,and the maximum theoretical reduction amount for the SPA-H slab with a transverse section of 145 mm×1600 mm was 41.8 mm,with corresponding reduction amounts for Segment 0 to Segment 4 of 15.8,7.3,6.5,6.4,and 5.8 mm,respectively.展开更多
For the first time,the linear and nonlinear vibrations of composite rectangular sandwich plates with various geometric patterns of lattice core have been analytically examined in this work.The plate comprises a lattic...For the first time,the linear and nonlinear vibrations of composite rectangular sandwich plates with various geometric patterns of lattice core have been analytically examined in this work.The plate comprises a lattice core located in the middle and several homogeneous orthotropic layers that are symmetrical relative to it.For this purpose,the partial differential equations of motion have been derived based on the first-order shear deformation theory,employing Hamilton’s principle and Von Kármán’s nonlinear displacement-strain relations.Then,the nonlinear partial differential equations of the plate are converted into a time-dependent nonlinear ordinary differential equation(Duffing equation)by applying the Galerkin method.From the solution of this equation,the natural frequencies are extracted.Then,to calculate the non-linear frequencies of the plate,the non-linear equation of the plate has been solved analytically using the method of multiple scales.Finally,the effect of some critical parameters of the system,such as the thickness,height,and different angles of the stiffeners on the linear and nonlinear frequencies,has been analyzed in detail.To confirmthe solution method,the results of this research have been compared with the reported results in the literature and finite elements in ABAQUS,and a perfect match is observed.The results reveal that the geometry and configuration of core ribs strongly affect the natural frequencies of the plate.展开更多
Core power is a key parameter of nuclear reactor.Traditionally,the proportional-integralderivative(PID)controllers are used to control the core power.Fractional-order PID(FOPID)controller represents the cutting edge i...Core power is a key parameter of nuclear reactor.Traditionally,the proportional-integralderivative(PID)controllers are used to control the core power.Fractional-order PID(FOPID)controller represents the cutting edge in core power control research.In comparing with the integer-order models,fractional-order models describe the variation of core power more accurately,thus provide a comprehensive and realistic depiction for the power and state changes of reactor core.However,current fractional-order controllers cannot adjust their parameters dynamically to response the environmental changes or demands.In this paper,we aim at the stable control and dynamic responsiveness of core power.Based on the strong selflearning ability of artificial neural network(ANN),we propose a composite controller combining the ANN and FOPID controller.The FOPID controller is firstly designed and a back propagation neural network(BPNN)is then utilized to optimize the parameters of FOPID.It is shown by simulation that the composite controller enables the real-time parameter tuning via ANN and retains the advantage of FOPID controller.展开更多
Lead chalcohalides(PbYX,X=Cl,Br,I;Y=S,Se)is an extension of the classic Pb chalcogenides(PbY).Constructing the heterogeneous integration with PbYX and PbY material systems makes it possible to achieve significantly im...Lead chalcohalides(PbYX,X=Cl,Br,I;Y=S,Se)is an extension of the classic Pb chalcogenides(PbY).Constructing the heterogeneous integration with PbYX and PbY material systems makes it possible to achieve significantly improved optoelectronic performance.In this work,we studied the effect of introducing halogen precursors on the structure of classical PbS nanocrystals(NCs)during the synthesis process and realized the preparation of PbS/Pb_(3)S_(2)X_(2) core/shell structure for the first time.The core/shell structure can effectively improve their optical properties.Furthermore,our approach enables the synthesis of Pb_(3)S_(2)Br_(2) that had not yet been reported.Our results not only provide valuable insights into the heterogeneous integration of PbYX and PbY materials to elevate material properties but also provide an effective method for further expanding the preparation of PbYX material systems.展开更多
The pore structures of the Majiagou Formation in the Ordos Basin are complex,featuring micro-and nano-scale intra-crystalline and inter-crystalline pores that significantly impact hydrocarbon storage and flow.Precisel...The pore structures of the Majiagou Formation in the Ordos Basin are complex,featuring micro-and nano-scale intra-crystalline and inter-crystalline pores that significantly impact hydrocarbon storage and flow.Precisely characterizing the rock internal structures is crucial for reservoir exploration and development.However,it is difficult to accurately characterize the pore structure of rock using traditional imaging methods to meet the simulation requirements.In this context,this study focuses on high-resolution 3D digital core reconstruction using the SliceGAN model.Specifically,the Modular Automated Processing System(MAPS)image and Quanti-tative Evaluation of Minerals by Scanning Electron Microscopy(QEMSCAN)image were combined to divide MAPS into three categories:pore,dolomite,and calcite.Then,through the SliceGAN algorithm,the 3D digital core was reconstructed.To evaluate the reconstruction,the auto-correlation function,two-point probability function,porosity,mineral content,and specific surface area were employed.The results show that the SliceGAN can effectively capture the micro-features in the core,and the internal structure of the generated core was consistent with that of the original core.This study provided a new sight for reconstructing cores with complex pore structures and strong heterogeneity and innovatively supports tight carbonate reservoir characterization and evaluation.展开更多
BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of cor...BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of core muscle activation and a person's ability to stabilize the lumbopelvic complex.Preparatory cues and images can be used to increase the activation of these muscles.To attain optimal movement patterns,it will be necessary to determine what cueing will give the most effective results for core stability.AIM To investigate the effects of external and internal cues on core muscle activation during the Sahrmann five-level core stability test.METHODS Total 68 participants(21.83±3.47 years)were randomly allocated to an external(n=35)or internal cue group(n=33).Participants performed the Sahrmann fivelevel core stability test without a cue as baseline and the five-level stability exercises with an internal or external cue.External cue group received a pressure biofeedback unit(PBU),and the internal cue group received an audio cue.A Delsys Trigno^(TM)surface electromyography unit was used for muscle activation from the rectus abdominis,external oblique,and transverse abdominis/internal oblique muscles.RESULTS Linear mixed effects model analysis showed that cueing had a significant effect on core muscle activation(P=0.001);however,there was no significant difference between cue types(internal or external)(P=0.130).CONCLUSION Both external and internal cueing have significant effects on core muscle activation during the Sahrmann five-level core stability test and the PBU does not create higher muscle activation than internal cueing.展开更多
基金supported by the Education Working Committee of the Xinjiang Uygur Autonomous Region Party Committee(grant number 2023GZYB10).
文摘This study aimed to explore how core self-evaluations and gender influence interpersonal adjustment and depression risk.Participants were 1748 college students(female=59.73%,male=40.27%,mean age=18.71 years,SD=0.78 years).The students completed the Interpersonal Adjustment Scale for College Students,Center for Epidemiological Studies Depression Scale,and Core Self-evaluation Scale.The results of Linear regression and mediated moderated effects modeling revealed that college students with higher interpersonal adjustment and core self-evaluation scores were at lower risk for depression.Core self-evaluation mediated the relationship between interpersonal adjustment and depression in college students for lower risk for depression.Gender moderated the relationship between interpersonal adjustment and core self-evaluation in college students for higher risk for depression in female students.From thesefindings,we conclude that interpersonal adjustment and core self-evaluation are significant for screening depression risk college students.Moreover,female students may benefit from targeted interventions aimed at their interpersonal adjustment for reducing their risk of depression.
基金supported by the National Social Science Foundation of China(20BSH131).
文摘Internet gaming disorder(IGD)among junior high school students is an increasingly prominent mental health concern.It is important to look for influences behind internet gaming disorder tendency(IGDT)in the junior high school student population.The present study aimed to reveal the explanatory mechanisms underlying the association between parental psychological control(PPC)and internet gaming disorder tendency among junior high school students by testing the mediating role of core self-evaluation(CSE)and the moderating role of intentional self-regulation(ISR).Participants in present study were 735 Chinese junior high school students who completed offline self-report questionnaires on parental psychological control,core self-evaluation,intentional self-regulation,and Internet gaming disorder tendency.Analyses were conducted via mediation and moderated mediation.The results showed that:(1)Parental psychological control was positively related to junior high school students’Internet gaming disorder tendency.Core self-evaluation,and intentional self-regulation were negatively related to junior high school students’Internet gaming disorder tendency,respectively.(2)Core self-evaluation partially mediated the relationship between parental psychological control and junior high school students’Internet gaming disorder tendency.(3)Intentional self-regulation moderated the association between parental psychological control and Internet gaming disorder tendency,as well as the relationships between parental psychological control and core self-evaluation and core self-evaluation and Internet gaming disorder tendency in the mediated model.Based on these findings,we believe that there is a need to weaken parental psychological control,strengthen junior high school students’core self-evaluation and intentional self-regulation,and to recognize the important role of parents as well as their children’s personal positive traits in the healthy development of junior high school students.
文摘The present study discusses the relationship among Chinese adolescents’parental involvement,core self-evaluation,and school adaptation.The Parental Involvement Behavior Questionnaire,Core Self-Evaluations Scale(CSES),and the School Adaptation Inventory were used to survey 1258 Chinese middle school students.The results showed that adolescents’school adaptation was significantly positively correlated with parental involvement and core self-evaluation.Furthermore,parental involvement and core self-evaluation were positively correlated.Mediation analysis found that core self-evaluation had partially mediated the relationship between adolescents’parental involvement and school adaption.Parental involvement could directly affect adolescents’school adaptation and indirectly affect school adaptation through the mediating effect of core self-evaluation.The present study results suggested that parents and educators could improve adolescents’school adaptation by increasing parental involvement and enhancing the adolescents’core self-evaluation.
基金funded by China’s National Social Science Fund,“The effect of community violence exposure on middle school students’social adjustment and its intervention countermeasures”(16BSH102).
文摘This study aimed to investigate the link between the exposure to intimate partner violence(IPV),core self-evaluations(CSE),and psychological adaptation of Chinese adolescents,through analysis of the results from the Survey of Children’s Exposure to Domestic Violence Scale,Core Self-Evaluations Scale,and Strengths and Difficulties Questionnaire,involving a total of 597 Chinese middle school students.It is indicated that the exposure to IPV is positively correlated with lower levels of psychological adaptation and CSE,and CSE is positively correlated with higher levels of psychological adaptation.Mediation analysis revealed that CSE partially mediated the association between the exposure to IPV and psychological adaptation.These results suggest that educators and parents should help adolescents tackle their emotional and behavioral problems by reducing the risk of IPV exposure and increasing their CSE.
文摘The rapid development of the internet has led to the rise of social networking sites,which have impacted the psychological health and social adaptation of college students.Existing research shows that the intensity and patterns of social networking site use are closely related to adolescents’core self-evaluations,with perceived social support playing a mediating role in this relationship.This study,based on a questionnaire survey of 231 college students with an average age of 19.5,reveals the intrinsic connection between social networking site use and core self-evaluations.The findings indicate that the intensity and pattern of use significantly affect self-evaluations,and perceived social support partially mediates this relationship.
基金The Ministry of Education of China supported this work under the Humanities and Social Sciences Research Project for Young Scholars(Grant No.20YJC890020).
文摘Background:Social anxiety is prevalent among adolescents and severely impacts their mental health and social functioning.This study aims to explore the underlying mechanisms and subgroup differences in adolescent social anxiety to provide a theoretical basis for targeted interventions.Methods:3025 Chinese adolescents(Meanage=13.91±1.60 years;47%male)completed self-report measures of physical activity,core self-evaluation,and social anxiety.Variable-centered analyses employed PROCESS Model 4 with 5000 bootstrap samples;covariates were gender,grade,and place of residence.Person-centered analyses used latent profile analysis in Mplus 8.3 to identify subgroups based on social anxiety item profiles.Results:Variable-centered analyses showed that physical activity had a significant negative association with social anxiety(β=−0.224,p<0.001)and a significant positive association with core self-evaluation(β=0.471,p<0.001);core self-evaluation partially mediated this relationship,accounting for 30%of the total effect.Person-centered analyses revealed an optimal two-profile solution:a low social anxiety profile(89.6%)and a high social anxiety profile(10.4%).The high social anxiety profile reported significantly lower physical activity and lower core self-evaluation than the low social anxiety profile.Conclusions:This study integrates variable-centered and person-centered evidence,identifies physical activity and core self-evaluation as key modifiable factors in reducing social anxiety,providing a theoretical basis for targeted and differentiated interventions.
文摘Informed by implicit leadership theories, this study investigates contemporary Chinese employees' preferences for paternalistic leadership (including three components: moral leadership, benevolent leadership and authoritarian leadership) and transformational leadership. It further examines the relationship between power distance orientation, core self-evaluation (CSE) and leadership preferences. The study finds that contemporary Chinese employees most prefer moral leadership, but are also highly receptive to transformational leadership. They prefer authoritarian leadership least. Moreover, preferences for authoritarian leadership are predicated on followers' power distance orientation. However, the opposite is true for moral leadership. CSE is positively related to followers' preference for authoritarian leadership, benevolent leadership and transformational leadership, but not except for moral leadership. A positive interaction effect is found between power distance orientation and CSE with regard to authoritarian leadership preference. The theoretical and practical implications of the findings are discussed.
文摘This study aims to examine the relationship between authentic leadership and employee proactive behavior. Based on self-determination theory, we argue that such a relationship is sequentially mediated by psychological empowerment and core self-evaluations. In addition, political skill plays a moderating role in the third stage. These hypotheses are validated by a sample of 65 leaders and 275 subordinates from two private enterprises in China's Mainland. Results show that authentic leadership Clime I) influences employees' proactive behavior Clime 3) through the psychological empowerment (Time I) and core self-evaluations of employees (Time 2), and the relationship between core self-evaluations and proactive behavior is positively moderated by employees' political skill. In addition, bootstrapping results also verify the moderating role played by employees' political skill in the indirect relationship between authentic leadership and proactive behavior through core self-evaluations. Theoretical and managerial implications are further discussed in the light of these findings.
基金financially supported by the National Natural Science Foundation of China(Nos.42272153 and 42472195)the Research Fund of PetroChina Tarim Oilfield Company(No.671023060003)the Research Fund of China National Petroleum Corporation Limited(No.2023ZZ16YJ04).
文摘Deep tight reservoirs exhibit complex stress and seepage fields due to varying pore structures,thus the seepage characteristics are significant for enhancing oil production.This study conducted triaxial compression and permeability tests to investigate the mechanical and seepage properties of tight sandstone.A digital core of tight sandstone was built using Computed Tomography(CT)scanning,which was divided into matrix and pore phases by a pore equivalent diameter threshold.A fluid-solid coupling model was established to investigate the seepage characteristics at micro-scale.The results showed that increasing the confining pressure decreased porosity,permeability,and flow velocity,with the pore phase becoming the dominant seepage channel.Cracks and large pores closed first under increasing pressure,resulted in a steep drop in permeability.However,permeability slightly decreased under high confining pressure,which followed a first-order exponential function.Flow velocity increased with seepage pressure.And the damage mainly occurred in stress-concentration regions under low seepage pressure.Seepage behavior followed linear Darcy flow,the damage emerged at seepage entrances under high pressure,which decreased rock elastic modulus and significantly increased permeability.
基金supported by the National Natural Science Foundation of China(12072136).
文摘Research on the mechanical–electrical properties is crucial for designing and preparing high-temperature superconducting(HTS)cables.Various winding core structures can influence the mechanical–electrical behavior of cables,but the impact of alterations in the winding core structure on the mechanical–electrical behavior of superconducting cables remains unclear.This paper presents a 3D finite element model to predict the performance of three cables with different core structures when subjected to transverse compression and axial tension.The three cables analyzed are CORC(conductor-on-round-core),CORT(conductor-on-round-tube),and HFRC(conductor-on-spiral-tube).A parametric analysis is carried out by varying the core diameter and inner-to-outer diameter ratio.Results indicate that the CORT cable demonstrates better performance in transverse compression compared to the CORC cable,aligning with experimental data.Among the three cables,the HFRC cables exhibit the weakest resistance to transverse deformation.However,the HFRC cable demonstrates superior tensile deformation resistance compared to the CORT cable,provided that the transverse compression properties are maintained.Finite element results also show that the optimum inner-to-outer diameter ratios for achieving the best transverse compression performance are approximately 0.8 for CORT cables and 0.6 for HFRC cables.Meanwhile,the study explores the effect of structural changes in HTS cable winding cores on their electromagnetic properties.It recommends utilizing small tape gaps,lower frequencies,and spiral core construction to minimize eddy losses.The findings presented in this paper offer valuable insights for the commercialization and practical manufacturing of HTS cables.
基金supported by the National Natural Science Foundation of China(No.52474355)the Liaoning Province Science and Technology Plan Joint Program(Key Research and Development Program Project),China(Nos.2022JH25/10200003 and 2023JH2/101800058).
文摘The application of liquid core reduction(LCR)technology in thin slab continuous casting can refine the internal microstruc-tures of slabs and improve their production efficiency.To avoid crack risks caused by large deformation during the LCR process and to minimize the thickness of the slab in bending segments,the maximum theoretical reduction amount and the corresponding reduction scheme for the LCR process must be determined.With SPA-H weathering steel as a specific research steel grade,the distributions of tem-perature and deformation fields of a slab with the LCR process were analyzed using a three-dimensional thermal-mechanical finite ele-ment model.High-temperature tensile tests were designed to determine the critical strain of corner crack propagation and intermediate crack initiation with various strain rates and temperatures,and a prediction model of the critical strain for two typical cracks,combining the effects of strain rate and temperature,was proposed by incorporating the Zener-Hollomon parameter.The crack risks with different LCR schemes were calculated using the crack risk prediction model,and the maximum theoretical reduction amount for the SPA-H slab with a transverse section of 145 mm×1600 mm was 41.8 mm,with corresponding reduction amounts for Segment 0 to Segment 4 of 15.8,7.3,6.5,6.4,and 5.8 mm,respectively.
文摘For the first time,the linear and nonlinear vibrations of composite rectangular sandwich plates with various geometric patterns of lattice core have been analytically examined in this work.The plate comprises a lattice core located in the middle and several homogeneous orthotropic layers that are symmetrical relative to it.For this purpose,the partial differential equations of motion have been derived based on the first-order shear deformation theory,employing Hamilton’s principle and Von Kármán’s nonlinear displacement-strain relations.Then,the nonlinear partial differential equations of the plate are converted into a time-dependent nonlinear ordinary differential equation(Duffing equation)by applying the Galerkin method.From the solution of this equation,the natural frequencies are extracted.Then,to calculate the non-linear frequencies of the plate,the non-linear equation of the plate has been solved analytically using the method of multiple scales.Finally,the effect of some critical parameters of the system,such as the thickness,height,and different angles of the stiffeners on the linear and nonlinear frequencies,has been analyzed in detail.To confirmthe solution method,the results of this research have been compared with the reported results in the literature and finite elements in ABAQUS,and a perfect match is observed.The results reveal that the geometry and configuration of core ribs strongly affect the natural frequencies of the plate.
文摘Core power is a key parameter of nuclear reactor.Traditionally,the proportional-integralderivative(PID)controllers are used to control the core power.Fractional-order PID(FOPID)controller represents the cutting edge in core power control research.In comparing with the integer-order models,fractional-order models describe the variation of core power more accurately,thus provide a comprehensive and realistic depiction for the power and state changes of reactor core.However,current fractional-order controllers cannot adjust their parameters dynamically to response the environmental changes or demands.In this paper,we aim at the stable control and dynamic responsiveness of core power.Based on the strong selflearning ability of artificial neural network(ANN),we propose a composite controller combining the ANN and FOPID controller.The FOPID controller is firstly designed and a back propagation neural network(BPNN)is then utilized to optimize the parameters of FOPID.It is shown by simulation that the composite controller enables the real-time parameter tuning via ANN and retains the advantage of FOPID controller.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFE0110300)the National Natural Science Foundation of China(Grant Nos.52372215,92163114,and 52202274)+5 种基金the Natural Science Foundation of Jiangsu Province of China(Grant No.BK20230504)the Special Fund for the"Dual Carbon"Science and Technology Innovation of Jiangsu province(Industrial Prospect and Key Technology Research program)(Grant Nos.BE2022023 and BE2022021)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(Grant No.21KJA430004)Gusu Innovation and Entre preneurship Leading Talent Program(Grant No.ZXL2022451)the China Postdoctoral Science Foundation(Grant No.2023M732523)supported by Suzhou Key Laboratory of Functional Nano&Soft Materials,Collaborative Innovation Center of Suzhou Nano Science&Technology,the 111 Project.
文摘Lead chalcohalides(PbYX,X=Cl,Br,I;Y=S,Se)is an extension of the classic Pb chalcogenides(PbY).Constructing the heterogeneous integration with PbYX and PbY material systems makes it possible to achieve significantly improved optoelectronic performance.In this work,we studied the effect of introducing halogen precursors on the structure of classical PbS nanocrystals(NCs)during the synthesis process and realized the preparation of PbS/Pb_(3)S_(2)X_(2) core/shell structure for the first time.The core/shell structure can effectively improve their optical properties.Furthermore,our approach enables the synthesis of Pb_(3)S_(2)Br_(2) that had not yet been reported.Our results not only provide valuable insights into the heterogeneous integration of PbYX and PbY materials to elevate material properties but also provide an effective method for further expanding the preparation of PbYX material systems.
基金financially supported by the open fund of Key Lab-oratory of Exploration Technologies for Oil and Gas Resources(Yangtze University),Ministry of Education,NO PI2023-03the open foundation of the National Engineering Laboratory for Exploration and Develop-ment of Low-Permeability Oil&Gas Fields and the National Natural Science Foundation of China(No.42474159).
文摘The pore structures of the Majiagou Formation in the Ordos Basin are complex,featuring micro-and nano-scale intra-crystalline and inter-crystalline pores that significantly impact hydrocarbon storage and flow.Precisely characterizing the rock internal structures is crucial for reservoir exploration and development.However,it is difficult to accurately characterize the pore structure of rock using traditional imaging methods to meet the simulation requirements.In this context,this study focuses on high-resolution 3D digital core reconstruction using the SliceGAN model.Specifically,the Modular Automated Processing System(MAPS)image and Quanti-tative Evaluation of Minerals by Scanning Electron Microscopy(QEMSCAN)image were combined to divide MAPS into three categories:pore,dolomite,and calcite.Then,through the SliceGAN algorithm,the 3D digital core was reconstructed.To evaluate the reconstruction,the auto-correlation function,two-point probability function,porosity,mineral content,and specific surface area were employed.The results show that the SliceGAN can effectively capture the micro-features in the core,and the internal structure of the generated core was consistent with that of the original core.This study provided a new sight for reconstructing cores with complex pore structures and strong heterogeneity and innovatively supports tight carbonate reservoir characterization and evaluation.
文摘BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of core muscle activation and a person's ability to stabilize the lumbopelvic complex.Preparatory cues and images can be used to increase the activation of these muscles.To attain optimal movement patterns,it will be necessary to determine what cueing will give the most effective results for core stability.AIM To investigate the effects of external and internal cues on core muscle activation during the Sahrmann five-level core stability test.METHODS Total 68 participants(21.83±3.47 years)were randomly allocated to an external(n=35)or internal cue group(n=33).Participants performed the Sahrmann fivelevel core stability test without a cue as baseline and the five-level stability exercises with an internal or external cue.External cue group received a pressure biofeedback unit(PBU),and the internal cue group received an audio cue.A Delsys Trigno^(TM)surface electromyography unit was used for muscle activation from the rectus abdominis,external oblique,and transverse abdominis/internal oblique muscles.RESULTS Linear mixed effects model analysis showed that cueing had a significant effect on core muscle activation(P=0.001);however,there was no significant difference between cue types(internal or external)(P=0.130).CONCLUSION Both external and internal cueing have significant effects on core muscle activation during the Sahrmann five-level core stability test and the PBU does not create higher muscle activation than internal cueing.