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Positive and negative risk-taking behaviors in adolescents:Distinct characteristics,interrelationships,and influencing factors
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作者 Jun-Jie Zhang En-Na Wang 《World Journal of Psychiatry》 2025年第6期21-33,共13页
Adolescence is a crucial period marked by significant developmental changes,during which risk-taking behaviors can be both a normative part of development and a potential source of concern.However,prior research has f... Adolescence is a crucial period marked by significant developmental changes,during which risk-taking behaviors can be both a normative part of development and a potential source of concern.However,prior research has focused predominantly on the adverse aspects of risk-taking(i.e.,negative risk-taking),overlooked the positive counterpart(i.e.,positive risk-taking),and lacked a detailed examination of both.This study aims to elucidate the distinct characteristics and interrelationships of positive and negative risk-taking behaviors among adoles-cents and to identify the key factors that influence these behaviors.Through a comprehensive synthesis of theoretical and empirical literature,we explore the multifaceted nature of risk-taking,highlighting its complex influencing factors,including individual traits,family dynamics,peer influence,school environment,and broader community contexts.By identifying the shared and unique factors contributing to positive and negative risk-taking behaviors,we can enable adolescents to navigate this complex stage of life and design targeted interventions.Future research directions include the application of person-centered approaches,the implementation of longitudinal tracking and the interactive effects of influencing factors,among other aspects. 展开更多
关键词 ADOLESCENCE Positive risk-taking Negative risk-taking Distinct characteristics INTERRELATIONSHIPS Influencing factors
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Development of a Self-Assessment Questionnaire for Nurses’ Risk-Taking Behavior in Medication
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作者 Yayoi Imura Chiharu Akazawa 《Health》 2022年第1期1-22,共22页
<strong>Purpose:</strong> The purpose of this study was to prepare a self-assessment questionnaire for nurses’ risk-taking behavior (RTB) in medication and to develop a reliable and valid questionnaire. &... <strong>Purpose:</strong> The purpose of this study was to prepare a self-assessment questionnaire for nurses’ risk-taking behavior (RTB) in medication and to develop a reliable and valid questionnaire. <strong>Method: </strong>In the first study, a draft of the self-evaluation questionnaire for nurses’ RTB in medication was prepared based on the literature study and qualitative analysis of important case information included in the Project to Collect Medical Near-miss/Adverse Event Information Annual Report of the Ministry of Health, Labor and Welfare. Following the studies, face validity was confirmed, and a questionnaire survey was conducted for nurses who oversee medication nationwide to verify the reliability and validity. <strong>Result: </strong>The number of subjects was 586 (valid response rate: 94.1%). Item analysis and exploratory factor analysis showed that 4 factors and 12 items for the RTBs in daily life and 4 factors and 20 items for RTBs in medication could be extracted. Confirmatory factor analysis confirmed the fit of the hypothetical model obtained by exploratory factor analysis. In addition, Cronbach’s α coefficient was 0.888. Thus, high reliability and validity were obtained. A correlation was found by comparing the total scores of each RTB factor with the incident/accident group, and a standard for self-evaluation value could be established (p < 0.01). <strong>Conclusions: </strong>We were able to develop a self-assessment questionnaire for nurses’ risk-taking behavior in medication. This questionnaire will be used by nurses to find out their trends. 展开更多
关键词 Self-Assessment Questionnaire risk-taking behavior Nurses MEDICATION
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Daily activity rhythms, chronotypes, and risk-taking behavior in the signal crayfish
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作者 Valerio SBRAGAGLIA Thomas BREITHAUPT 《Current Zoology》 SCIE CAS CSCD 2022年第2期177-183,共7页
Consistent inter-individual differences in daily activity rhythms(i.e.,chronotypes)can have ecological consequences in determining access to food resources and avoidance of predators.The most common measure to charact... Consistent inter-individual differences in daily activity rhythms(i.e.,chronotypes)can have ecological consequences in determining access to food resources and avoidance of predators.The most common measure to characterize chronotypes in animals as well as humans is the onset of activity(i.e.,early or late chronotypes).However,daily activity rhythms may also differ in the relative amount of activity displayed at particular time periods.Moreover,chronotypes may also be linked to other consistent inter-individual differences in behavior(i.e.,personality),such as the propensity to take risks.Here,we used the signal crayfish Pacifastacus leniusculusto test the presence of chronotypes and risk-taking personality traits and a potential behavioral syndrome between these traits.We first exposed crayfish to 5 days of light-darkness to measure daily activity rhythms and then we applied a visual predator-simulating stimulus in 2 different contexts(neutral and food).Our results showed consistent(i.e.,across 5 days)inter-individual differences in the relative nocturnal activity displayed in the early and middle,but not in the late part of darkness hours.Moreover,while crayfish displayed inter-individual differences in risk-taking behavior,these were not found to be consistent across 2 contexts.Therefore,we were not able to formally test a behavioral syndrome between these 2 traits.In conclusion,our study provides the first evidence of chronotypes in the relative amount of activity displayed at particular time periods.This could be a valuable information for applied ecological aspects related to the signal crayfish,which is a major invasive species of freshwater ecosystems. 展开更多
关键词 behavioral syndrome biological rhythms BOLDNESS FEEDING locomotor activity
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Risk-taking path choice behaviors under ATIS in transportation networks with demand uncertainty 被引量:2
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作者 Shao, Hu Tian, Qiong +1 位作者 Yuan, Xiaoming Wang, Guodong 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期43-48,共6页
A new travel time reliability-based traffic assignment model is proposed to investigate the effects of an advanced transportation information system (ATIS) on drivers' risk-taking path choice behaviours in transpo... A new travel time reliability-based traffic assignment model is proposed to investigate the effects of an advanced transportation information system (ATIS) on drivers' risk-taking path choice behaviours in transportation networks with demand uncertainty. In the model, drivers are divided into two classes. The first class is not equipped with ATIS, while the second class is equipped with ATIS. Different risk-taking path choice behaviours of the two classes are studied, respectively. A corresponding mixed equilibrium traffic assignment model is formulated as a variational inequality problem in terms of path flows, which is solved by a heuristic solution algorithm. Numerical results indicate that the ATIS can influence the drivers' risk-taking path choice behaviours and the total system travel time in transportation networks with demand uncertainty. It is also found that under higher demand levels, the benefits of ATIS for network performance enhancement may be more obvious. 展开更多
关键词 risk-taking path choice behaviours advanced transportation information system (ATIS) demand uncertainty traffic assignment problem variational inequality
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Corporate Governance,Macroprudential Regulation,and Bank Risk-Taking
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作者 Hu Xiliang Han Xiulian Sun He 《Contemporary Social Sciences》 2025年第1期31-46,共16页
Effective corporate governance and sound macroprudential policies are crucial to the stability and sustainable development of the banking sector in China.This paper uses panel data sets from 31 listed Chinese commerci... Effective corporate governance and sound macroprudential policies are crucial to the stability and sustainable development of the banking sector in China.This paper uses panel data sets from 31 listed Chinese commercial banks between 2007 and 2023 to examine how corporate governance and macroprudential regulation influence bank risk-taking.To achieve this,we constructed a set of micro-level corporate governance indicators.The findings show that corporate governance significantly reduces bank risk-taking,while macroprudential regulation positively moderates this relationship.Furthermore,business diversification and loan concentration are the key mechanisms through which corporate governance mitigates risk-taking.We confirmed the soundness of these findings by using robust econometric techniques,including difference-in-differences,system GMM,and alternative independent variables.This study provides valuable insights for optimizing bank capital structures,enhancing corporate governance,improving personnel management,and clarifying the roles of regulators in refining the macroprudential regulatory framework. 展开更多
关键词 corporate governance macroprudential regulation bank risk-taking
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Method for Behavior Recognition of Hu Sheep in Intensive Farming Based on HLNC-YOLO
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作者 JI Ronghua CHANG Hongrui +2 位作者 ZHANG Suoxiang LIU Zhongying WU Zhonghong 《农业机械学报》 北大核心 2026年第2期265-275,共11页
Behavior recognition of Hu sheep contributes to their intensive and intelligent farming.Due to the generally high density of Hu sheep farming,severe occlusion occurs among different behaviors and even among sheep perf... Behavior recognition of Hu sheep contributes to their intensive and intelligent farming.Due to the generally high density of Hu sheep farming,severe occlusion occurs among different behaviors and even among sheep performing the same behavior,leading to missing and false detection issues in existing behavior recognition methods.A high-low frequency aggregated attention and negative sample comprehensive score loss and comprehensive score soft non-maximum suppression-YOLO(HLNC-YOLO)was proposed for identifying the behavior of Hu sheep,addressing the issues of missed and erroneous detections caused by occlusion between Hu sheep in intensive farming.Firstly,images of four typical behaviors-standing,lying,eating,and drinking-were collected from the sheep farm to construct the Hu sheep behavior dataset(HSBD).Next,to solve the occlusion issues,during the training phase,the C2F-HLAtt module was integrated,which combined high-low frequency aggregation attention,into the YOLO v8 Backbone to perceive occluded objects and introduce an auxiliary reversible branch to retain more effective features.Using comprehensive score regression loss(CSLoss)to reduce the scores of suboptimal boxes and enhance the comprehensive scores of occluded object boxes.Finally,the soft comprehensive score non-maximal suppression(Soft-CS-NMS)algorithm filtered prediction boxes during the inferencing.Testing on the HSBD,HLNC-YOLO achieved a mean average precision(mAP@50)of 87.8%,with a memory footprint of 17.4 MB.This represented an improvement of 7.1,2.2,4.6,and 11 percentage points over YOLO v8,YOLO v9,YOLO v10,and Faster R-CNN,respectively.Research indicated that the HLNC-YOLO accurately identified the behavior of Hu sheep in intensive farming and possessed generalization capabilities,providing technical support for smart farming. 展开更多
关键词 behavior recognition YOLO loss function attention mechanism
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Effect of Initial Microstructure States on Flow Behavior of Al-Zn-Mg-Cu Alloy During Hot Tensile Deformation
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作者 Wang Shuyan Zhou Yuting +3 位作者 Du Ruibo Long Shuai Lin Haitao Wang Shaoyang 《稀有金属材料与工程》 北大核心 2026年第2期302-314,共13页
To investigate the influence of Al-Zn-Mg-Cu alloy with as-homogenized and as-rolled initial microstructures on the tensile flow behavior,isothermal tensile tests were conducted on a GLEEBLE-3500 isothermal simulator a... To investigate the influence of Al-Zn-Mg-Cu alloy with as-homogenized and as-rolled initial microstructures on the tensile flow behavior,isothermal tensile tests were conducted on a GLEEBLE-3500 isothermal simulator at temperatures of 380-440℃and strain rates of 0.05-1 s^(−1).The Johnson-Cook model,Hensel-Spittel model,strain-compensated Arrhenius model,and critical fracture strain model were established.Results show that through the evaluation of the models using the correlation coefficient(R)and the average absolute relative error,the strain-compensated Arrhenius model can represent the flow behavior of the alloy more accurately.Shear bands are more pronounced in the as-homogenized specimens,whereas dynamic recrystallization is predominantly observed in as-rolled specimens.Fracture morphology analysis reveals that a mixed fracture mechanism is prevalent in the as-homogenized specimen,whereas a ductile fracture mechanism is predominant in the as-rolled specimen.The processing maps indicate that the unstable region is reduced in the as-rolled specimens compared with that in the as-homogenized specimens.The optimal hot working windows for the as-homogenized and as-rolled specimens are determined as 410-440℃/0.14-1 s^(−1)and 380-400℃/0.05-0.29 s^(−1),respectively. 展开更多
关键词 Al-Zn-Mg-Cu alloy tensile flow behavior MICROSTRUCTURE constitutive modelling processing map
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Dynamic Behaviors of Localized Waves of the(2+1)-Dimensional Yu-Toda-Sasa-Fukuyama Equation
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作者 SUN Xiaoqing XIA Yarong +1 位作者 YAO Ruoxia WANG Weiqing 《应用数学》 北大核心 2026年第2期624-638,共15页
In this article,by employing the Hirota bilinear approach and the long wave limit method,we not only derive soliton solutions,lump solutions,and hybrid solutions for the(2+1)-dimensional Yu-Toda-Sasa-Fukuyama(YTSF)equ... In this article,by employing the Hirota bilinear approach and the long wave limit method,we not only derive soliton solutions,lump solutions,and hybrid solutions for the(2+1)-dimensional Yu-Toda-Sasa-Fukuyama(YTSF)equation,but also analyze the dynamical behaviors of nonlinear local wave propagation in shallow water.Firstly,based on the Hirota bilinear approach,one to four-order soliton solutions of the YTSF equation are obtained,and the effects of different parameters on the amplitude,propagation trajectory,and displacement of solitons are investigated.Secondly,using the long wave limit approach,one to three-order lump solutions and various physical quantities of the YTSF equation are derived.It is found that the real and imaginary parts of the parameter pi dominate the propagation trajectory and the shape of lump waves,respectively.Furthermore,we construct the hybrid solution for the YTSF equation,leading to the conclusion that the interaction between lumps and solitons constitutes an elastic collision.To intuitively understand the dynamic behaviors of these solutions,we conduct numerical simulations to present vivid three-dimensional visualizations. 展开更多
关键词 (2+1)-dimensional Yu-Toda-Sasa-Fukuyama equation Hirota bilinear approach Lump solutions Dynamic behaviors
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Correction: Optimizing Exciton and Charge-Carrier Behavior in Thick-Film Organic Photovoltaics: A Comprehensive Review
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作者 Lu Wei Yaxin Yang +2 位作者 Lingling Zhan Shouchun Yin Hongzheng Chen 《Nano-Micro Letters》 2026年第1期608-608,共1页
Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.Th... Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.The published version showed“Hongzhen Chen”,whereas the correct spelling should be“Hongzheng Chen”.The correct author name has been provided in this Correction,and the original article[1]has been corrected. 展开更多
关键词 charge carrier behavior exciton behavior comprehensive review thick film organic photovoltaics nano micro letters
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Urban-rural differences in residential energy-use behavior and energy-saving awareness:Evidence from a Chinese megacity
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《建筑节能(中英文)》 2026年第2期150-150,共1页
Residential energy-use behavior and energy-saving awareness play a crucial role in sustainable urban energy planning and building energy efficiency,particularly under the pressures of climate change.However,existing s... Residential energy-use behavior and energy-saving awareness play a crucial role in sustainable urban energy planning and building energy efficiency,particularly under the pressures of climate change.However,existing studies often lack comparative analysis of urban-rural differences and tend to focus excessively on behavior patterns while neglecting the dimension of energysaving awareness.With China’s urbanization rate reaching 66.16%,understanding such regional disparities has become increasingly important.To address these research gaps,this study conducts a large-scale survey on space cooling behaviors among residents in Beijing,a representative Chinese megacity.It should be noted that living standards in such megacities are generally higher than the national average,which may shape distinctive energy-use profiles.Analyzing 1573valid samples(1064 urban/442 rural)in 2024,this study employed K-Prototypes and K-Modes clustering to identify typical cooling behavior and energy-saving awareness pattems,followed by Kendall/Chi-square correlation tests and XGBoost importance analysis to determine key influencing factors,with subsequent urban-rural comparative analysis.Results indicate that urban residents are primarily heat-sensitive or heat-tolerant,with a secondary patten of mid-low temperature preference,and generally exhibit long cooling durations;rural behavior is dominated by heat-tolerant type,followed by heat-sensitive,mid-low temperature preference,and never-on types as secondary patterns;both urban and rural areas exhibit energy-savingawareness characterized by low consumption-lowwillingness,though urban areas show marginally higher motivation;energy-saving awareness correlates with cooling behavior in rural areas,but this relationship weakens significantly in urban contexts. 展开更多
关键词 behavior patterns such regional disparities energy saving awareness residential energy use behavior climate change urban rural differences China Beijing
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Energy economic analysis of vehicle driving decisions: Eco-driving behavior assessment
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作者 ZHOU Shi-jie TIAN Feng 《Ecological Economy》 2026年第1期67-82,共16页
Eco-driving behaviors have been recommended around the world because the transport is a key factor of energy use and pollution emissions.Therefore,based on the driving decision model,this paper introduces three aspect... Eco-driving behaviors have been recommended around the world because the transport is a key factor of energy use and pollution emissions.Therefore,based on the driving decision model,this paper introduces three aspects of the driving decisions(strategic decision,tactical decision and operation decision)to analyze the economy of vehicle energy.The analytic hierarchy process(AHP)is used to assign the weight of the internal evaluation indexes,so as to form a complete assessment for drivers'eco-driving behaviors.The research result can not only quantitatively describe the energy-saving effect of drivers'decisions,but also put forward targeted driving suggestions to optimize drivers'eco-driving behaviors.This assessment model helps to clarify the potential of eco-driving on energy economy of transportation in a hierarchical way,and provides a valuable theoretical basis for the further promotion and application of eco-driving education. 展开更多
关键词 eco-driving energy economy driving decision behavior assessment
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Investigating the Dynamic Behavior of Bubbles in Oil During Partial Discharge
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作者 Hongbin Wu Hongshun Liu +7 位作者 Yifan Wang Pengfei Lu Luyao Liu Hanliang Lin Dongxin He Qingmin Li Qingquan Li Weijiang Chen 《CSEE Journal of Power and Energy Systems》 2026年第1期547-556,共10页
The partial discharge occurring in the weak part of the insulation of a converter transformer results in the formation of a large number of bubbles in the insulating oil.The migration,deformation,and other dynamic beh... The partial discharge occurring in the weak part of the insulation of a converter transformer results in the formation of a large number of bubbles in the insulating oil.The migration,deformation,and other dynamic behaviors of bubbles in the region of a strong electric field can cause them to easily accumulate into“small bridges”of impurities that can lead to breakdown of the oil gap.The authors of this study experimentally investigate and discuss the mechanisms of migration and deformation of bubbles in oil during partial discharge under composite AC/DC voltage to clarify their dynamic behaviors.The influence of the initial position of the bubbles on their trajectory of migration and velocity as well as the morphological changes occurring in them are analyzed using numerical simulations.The results show that the bubbles move away from the strong electric field due to the action of the dielectrophoretic force.The interface of the bubbles is longitudinally stretched under the action of the electrostrictive force and the vertical component of the drag force and gradually recovers to assume a spherical shape under the influence of surface tension and the horizontal component of the drag force. 展开更多
关键词 BUBBLE converter transformer dynamic behavior partial discharge
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ADCP-YOLO:A High-Precision and Lightweight Model for Violation Behavior Detection in Smart Factory Workshops
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作者 Changjun Zhou Dongfang Chen +1 位作者 Chenyang Shi Taiyong Li 《Computers, Materials & Continua》 2026年第3期1895-1919,共25页
With the rapid development of smart manufacturing,intelligent safety monitoring in industrial workshops has become increasingly important.To address the challenges of complex backgrounds,target scale variation,and exc... With the rapid development of smart manufacturing,intelligent safety monitoring in industrial workshops has become increasingly important.To address the challenges of complex backgrounds,target scale variation,and excessive model parameters in worker violation detection,this study proposes ADCP-YOLO,an enhanced lightweight model based on YOLOv8.Here,“ADCP”represents four key improvements:Alterable Kernel Convolution(AKConv),Dilated-Wise Residual(DWR)module,Channel Reconstruction Global Attention Mechanism(CRGAM),and Powerful-IoU loss.These components collaboratively enhance feature extraction,multi-scale perception,and localization accuracy while effectively reducing model complexity and computational cost.Experimental results show that ADCP-YOLO achieves a mAP of 90.6%,surpassing YOLOv8 by 3.0%with a 6.6%reduction in parameters.These findings demonstrate that ADCP-YOLO successfully balances accuracy and efficiency,offering a practical solution for intelligent safety monitoring in smart factory workshops. 展开更多
关键词 YOLO violation behavior detection AKConv CRGAM DWR Powerful-IoU
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A Study on the Correlation between Peer Caring Behavior and Empathy among Undergraduate Nursing Students
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作者 Fang Xu Juan Xiao +2 位作者 Xiaofang Hu Jianfeng Xu Shaoyan Yuan 《Journal of Clinical and Nursing Research》 2026年第2期343-349,共7页
Objective: To understand the current status of peer caring behavior and empathy among undergraduate nursing students and to explore the relationship between the two. Method: Using the convenience sampling method, a qu... Objective: To understand the current status of peer caring behavior and empathy among undergraduate nursing students and to explore the relationship between the two. Method: Using the convenience sampling method, a questionnaire survey was conducted among 292 nursing students from a medical college in Jiangxi Province, using the Peer Caring Behavior Scale and the Jefferson Scale of Empathy. Results: The score for peer caring behavior among undergraduate nursing students was 85.00 (78.00-92.00), and the score for empathy was 101.00 (92.00-110.00). A positive correlation was found between the two (r = 0.362, p < 0.05). Conclusion: The level of peer caring behavior among undergraduate nursing students is above average, while their empathy level is moderate, with a positive correlation between the two. This suggests that nursing educators should strengthen the development of peer caring behavior, which may help enhance the empathy of undergraduate nursing students. 展开更多
关键词 Undergraduate nursing students Peer caring behavior EMPATHY CORRELATION
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Corrosion behavior of 650 MPa high strength low alloy steel in industrial polluted environments containing different concentrations of Cl^(-)
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作者 Lianjun Hao Xiaokun Cai +4 位作者 Tianqi Chen Chenyu Zhang Chao Liu Xuequn Cheng Xiaogang Li 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期228-241,共14页
This study utilizes wet/dry cyclic corrosion testing combined with corrosion big data technology to investigate the mechanism by which chloride ions(Cl^(-))influence the corrosion behavior of 650 MPa high-strength low... This study utilizes wet/dry cyclic corrosion testing combined with corrosion big data technology to investigate the mechanism by which chloride ions(Cl^(-))influence the corrosion behavior of 650 MPa high-strength low-alloy(HSLA)steel in industrially polluted environments.The corrosion process of 650 MPa HSLA steel occurred in two distinct stages:an initial corrosion stage and a stable corrosion stage.During the initial phase,the weight loss rate increased rapidly owing to the instability of the rust layer.Notably,this study demonstrated that 650 MPa HSLA steel exhibited superior corrosion resistance in Cl-containing environments.The formation of a corrosion-product film eventually reduced the weight-loss rate.However,the intrusion of Cl^(-)at increasing concentrations gradually destabilized theα/γ^(*)phases of the rust layer,leading to a looser structure and lower polarization resistance(R_(p)).The application of corrosion big data technology in this study facilitated the validation and analysis of the experimental results,offering new insights into the corrosion mechanisms of HSLA steel in chloride-rich environments. 展开更多
关键词 HSLA steel CHLORINE corrosion behavior corrosion big data
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The Impact of Motivational Nursing under a Focus-Resolving Model on the Health Behaviors of Bladder Cancer Surgery Patients
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作者 Ying Chen Qiaoyan Zhao 《Journal of Clinical and Nursing Research》 2026年第2期350-356,共7页
Objective: To analyze the impact of motivational nursing under the solution-focused approach on health behaviors in surgical care for bladder cancer patients. Methods: A sample of 72 bladder cancer patients who underw... Objective: To analyze the impact of motivational nursing under the solution-focused approach on health behaviors in surgical care for bladder cancer patients. Methods: A sample of 72 bladder cancer patients who underwent surgical treatment from September 2024 to September 2025 was randomly divided into groups using a random number table. Group A received motivational nursing under the solution-focused approach, while Group B received conventional nursing. Health behavior scores and complication indicators were compared between the two groups. Results: Group A had higher scores on the Health-Promoting Lifestyle Profile II (HPLP-Ⅱ) than Group B, with p < 0.05. The postoperative complication rate in Group A was lower than that in Group B, with p < 0.05. Conclusion: For bladder cancer patients undergoing surgery, receiving motivational nursing under the solution-focused approach can improve health behaviors, alleviate negative emotions, and is highly feasible and effective. 展开更多
关键词 Bladder cancer Motivational nursing Solution-focused approach Health behaviors
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Volume change and creep behaviors related to stress-phase transition path in methane hydrate-bearing silty sand
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作者 Jiazuo Zhou Qi Fan +1 位作者 Zhenyu Zhu Changfu Wei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1526-1540,共15页
The volume change behavior of natural gas hydrate-bearing sediment is essential as it influences settlement,strength,and stiffness,which directly affect the stability of hydrate reservoirs during hydrate extraction or... The volume change behavior of natural gas hydrate-bearing sediment is essential as it influences settlement,strength,and stiffness,which directly affect the stability of hydrate reservoirs during hydrate extraction or in response to environmental changes.The volume change is influenced not only by stress but also by the formation and dissociation of hydrates.This study adopted a customized apparatus for one-dimensional compression tests,allowing independent control of gas pressure and effective stress.Tests were conducted on samples with different hydrate saturations along various temperature-gas pressure-effective stress paths,yielding some conclusions related to compressibility and creep.An unusual phenomenon was observed under low-stress conditions:hydrate formation led to shrinkage rather than expansion.Three potential mechanisms behind this occurrence were discussed.As hydrate saturation increases,the yield stress rises while the compression and swelling indexes remain minimally affected.After hydrate dissociation,the compression curve of hydrate-bearing sediment drops to that of hydrate-free sediment.Once hydrate is formed,the compression curve of hydrate-free sediment gradually approaches that of hydrate-bearing sediment during the subsequent loading.Under low-stress conditions,the creep of both hydrate-free and hydrate-bearing sediments is very weak.However,when stress increases,significantly beyond the yield stress,the creep of both sediments increases significantly,with hydrate-bearing sediment exhibiting much greater creep than hydrate-free sediment. 展开更多
关键词 Hydrate-bearing sediment Phase transition Volume change Creep behavior
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Reduction and migration behavior of phosphorus in coal-based reduction of high-phosphorus oolitic iron ore
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作者 Meng-Jie Hu De-Qing Zhu +4 位作者 Jian Pan Zheng-Qi Guo Cong-Cong Yang Si-Wei Li Wen Cao 《Journal of Iron and Steel Research International》 2026年第3期88-105,共18页
Phosphorus tends to migrate into metallic iron during the direct reduction of high-phosphorus oolitic iron ore,leading to undesirable phosphorus enrichment in metallic iron.However,the underlying reduction and migrati... Phosphorus tends to migrate into metallic iron during the direct reduction of high-phosphorus oolitic iron ore,leading to undesirable phosphorus enrichment in metallic iron.However,the underlying reduction and migration mechanisms remain poorly understood.Phosphorus behavior during coal-based reduction was systematically investigated through theoretical modeling and experimental approaches.Thermodynamic analysis revealed that the carbon reduction of solid Ca_(3)(PO_(4))_(2)to gaseous P_(2)requires temperatures exceeding 1400℃.Notably,this threshold significantly decreases to 1130.5℃in the presence of SiO_(2)and Al_(2)O_(3).Further investigations demonstrated that Ca_(3)(PO_(4))_(2)co-reduces with Fe_(x)O_(γ)in the presence of SiO_(2)-Al_(2)O_(3)-Fe_(x)O_(γ),forming Fe_(3)P(instead of gaseous P_(2))at a markedly lower temperature of 778.7℃.Mechanistic studies indicate that the inherent thermal stability of Ca_(3)(PO_(4))_(2)inhibits the generation of reactive[P_(2)O_(5)].However,SiO_(2)-Al_(2)O_(3)coexistence destabilizes Ca_(3)(PO_(4))_(2)while exponentially enhancing[P_(2)O_(5)]activity.This synergistic effect dramatically promotes the phosphorus mineral reduction.Characterization confirmed that Ca_(3)(PO_(4))_(2)migrated into the slag phase(4FeO·Al_(2)O_(3)·3SiO_(2)·CaO·P_(2)O_(5)).Subsequently,the reactive P_(2)O_(5)in slag is reduced with metallic iron to form Fe_(3)P,which further dissolves into theα-Fe matrix through solid-state diffusion,ultimately generating Fe-P solid solutions. 展开更多
关键词 Oolitic hematite ore Coal-based reduction Migration behavior DEPHOSPHORIZATION
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Deviation Behavior Analysis and Detection Based on Flight Trajectory Data
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作者 WU Yexin ZHAO Yifei WANG Hongyong 《Transactions of Nanjing University of Aeronautics and Astronautics》 2026年第1期127-144,共18页
Flight behavior analysis provides the fundamental basis for the future development of air traffic management(ATM).The characteristics of aircraft behavior are inherently reflected in their flight trajectories,impactin... Flight behavior analysis provides the fundamental basis for the future development of air traffic management(ATM).The characteristics of aircraft behavior are inherently reflected in their flight trajectories,impacting flight efficiency and safety levels.However,existing research largely addresses inefficient or abnormal trajectories from a single perspective,with an absence of a unified evaluation standard.This paper introduces a method for analyzing flight deviation behavior based on automatic dependent surveillance-broadcast(ADS-B)data,defining novel metrics of trajectory redundancy and trajectory deviation.An adaptive detection algorithm is developed to capture diverse deviation patterns.Results reveal that higher trajectory redundancy is linked to lower operational efficiency,while trajectory deviation effectively identify stepped descents,holding patterns,detours,and other behaviors.The approach offers data-driven support for anomaly detection,performance evaluation and air traffic management,with substantial significance for civil aviation applications. 展开更多
关键词 deviation behavior flight trajectory flight safety operational efficiency DATA-DRIVEN
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Escape behavior and refuge selection preferences by two common urban birds
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作者 Haijie Zhang Yining Li +3 位作者 Yiran Wang Guofen Zhu Jiaojiao Wang Laikun Ma 《Avian Research》 2026年第1期84-94,共11页
Urbanization destroys wildlife habitats,fragmenting them into small patches with poor connectivity,leading to population declines in species sensitive to such chan ges.Escape is the most common anti-predator strategy ... Urbanization destroys wildlife habitats,fragmenting them into small patches with poor connectivity,leading to population declines in species sensitive to such chan ges.Escape is the most common anti-predator strategy adopted by birds,refuges in habitats reduce or eliminate predation risk.Therefore,creating habitats with suitable refuges for birds has significant implications for their conservation.However,there have been few studies on refuge selection in birds.This study examined the Eurasian Tree Sparrow(Passer montanus)and Oriental Magpie(Pica serica)in urban and rural areas of Chengde City,northern China by measuring their alert distance(AD),flight initiation distance(FID),an d distance fled(DF)and analyzed their refuge selection characteristics after escaping.The FID/AD ratio was employed to assess the behavioral differences of birds in the risk trade-off.The results showed that the FID and FID/AD of both species were lower in urban areas than in rural areas and were negatively correlated with immediate human density.Sparrow FID was significantly affected by group size and landing substrate type.The FID of sparrows was positively correlated with the group size.The sparrows that fled to bushes escaped earlier.In urban and rural areas,sparrows exhibited significantly lower FID,DF,and FID/AD than magpies.The species adopted different refuge selection strategies,with magpies preferentially selecting trees with greater vertical height and sparrows selecting both trees and bushes.Further analysis indicated that the horizontal and vertical distances fled of both species were lower when fleeing to bushes.Urban planning and conservation areas construction should incorporate the ecological needs of local bird species to rationally configure their habitat structure,thereby optimizing the effect of avian conservation. 展开更多
关键词 Anti-predator behavior Avian tolerance Flight initiation distance REFUGE URBANIZATION
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