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Marital Status as a Moderator:Exploring the Relationship between Social Engagement and Depressive Symptoms in China’s Older Adult Population
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作者 Jianlun Wu Yaping Ye +4 位作者 Man Zhang Ruichen Cong Yitao Chen Pengfei Yu Qing Guo 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第10期1142-1157,共16页
Objective This study aims to explore the complex relationship between social engagement and depressive symptoms among older adults in China,focusing particularly on the moderating role of marital status.Methods This s... Objective This study aims to explore the complex relationship between social engagement and depressive symptoms among older adults in China,focusing particularly on the moderating role of marital status.Methods This study used data from the latest Chinese Longitudinal Healthy Longevity Survey(CLHLS).The analysis used the latent class analysis to delineate personality clusters and hierarchical linear regression,supplemented by the PROCESS macro,to investigate the effects of social engagement and marital status on depressive symptoms.Results The analysis encompassed 7,789 respondents(mean age:82.53[s=11.20]years),with 54%female.The personality analysis categorized participants into four clusters,with the majority(77.60%)classified as Confident Idealists,who exhibited the lowest levels of depressive symptoms.Hierarchical linear regression analysis yielded several significant findings:Higher levels of social engagement were significantly associated with fewer depressive symptoms(t=-7.932,P<0.001,B=-0.463).Marital status was a significant factor;married individuals reported fewer depressive symptoms compared to their unmarried counterparts(t=-6.368,P<0.001,B=-0.750).There was a significant moderating effect of marital status on the relationship between social engagement and depressive symptoms(t=-2.092,P=0.037,B=-0.217).Conclusion This study demonstrates that,among Chinese older adults,both social engagement and marital status significantly influence depressive symptoms.Higher social engagement,particularly in other activities like doing household chores,gardening,reading newspapers or books,and playing cards or Mahjong,is associated with fewer depressive symptoms,especially among married individuals. 展开更多
关键词 Social engagement Depressive symptoms Marital status MODERATOR Older adults
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Re-Distributing Facial Features for Engagement Prediction with ModernTCN
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作者 Xi Li Weiwei Zhu +2 位作者 Qian Li Changhui Hou Yaozong Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第10期369-391,共23页
Automatically detecting learners’engagement levels helps to develop more effective online teaching and assessment programs,allowing teachers to provide timely feedback and make personalized adjustments based on stude... Automatically detecting learners’engagement levels helps to develop more effective online teaching and assessment programs,allowing teachers to provide timely feedback and make personalized adjustments based on students’needs to enhance teaching effectiveness.Traditional approaches mainly rely on single-frame multimodal facial spatial information,neglecting temporal emotional and behavioural features,with accuracy affected by significant pose variations.Additionally,convolutional padding can erode feature maps,affecting feature extraction’s representational capacity.To address these issues,we propose a hybrid neural network architecture,the redistributing facial features and temporal convolutional network(RefEIP).This network consists of three key components:first,utilizing the spatial attention mechanism large kernel attention(LKA)to automatically capture local patches and mitigate the effects of pose variations;second,employing the feature organization and weight distribution(FOWD)module to redistribute feature weights and eliminate the impact of white features and enhancing representation in facial feature maps.Finally,we analyse the temporal changes in video frames through the modern temporal convolutional network(ModernTCN)module to detect engagement levels.We constructed a near-infrared engagement video dataset(NEVD)to better validate the efficiency of the RefEIP network.Through extensive experiments and in-depth studies,we evaluated these methods on the NEVD and the Database for Affect in Situations of Elicitation(DAiSEE),achieving an accuracy of 90.8%on NEVD and 61.2%on DAiSEE in the fourclass classification task,indicating significant advantages in addressing engagement video analysis problems. 展开更多
关键词 engagement prediction spatiotemporal network re-distributing facial features temporal convolutional network
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基于MITRE Engage模型的网络安全能力建设思路
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作者 梁晴 《信息安全与通信保密》 2024年第9期63-70,共8页
基于MITRE Engage模型在获取攻击方TTPs方面的优势,提出了基于MITRE Engage模型的网络安全建设思路。以识别网络安全建设关键过程域为主线,网络安全能力建设为内容,网络安全成熟度等级为结论展开网络安全能力建设的研究。基于MITRE Eng... 基于MITRE Engage模型在获取攻击方TTPs方面的优势,提出了基于MITRE Engage模型的网络安全建设思路。以识别网络安全建设关键过程域为主线,网络安全能力建设为内容,网络安全成熟度等级为结论展开网络安全能力建设的研究。基于MITRE Engage模型,识别了网络欺骗、对抗行动和行为分析3个关键过程域;构建了伪装、引导、遏制、检测、促进、收集、推理7项安全能力维度;基于安全能力维度,区分了普通、进阶和高级3级威胁防御成熟度。该思路能够使MITRE Engage模型快速落地,建立清晰的网络安全体系,提高网络安全防御能力,确保网络系统的安全稳定运行。 展开更多
关键词 MITRE engage 网络安全建设 TTPs 关键过程域 安全能力 安全成熟度等级
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The Importance of Stakeholder Engagement in Progressive Rehabilitation of Large-Scale Open Pit Mines—A Case Study of Lumwana Mine
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作者 Mususu Kosta Mpongo Kaonda Baxter Nsontaulwa 《Journal of Environmental Protection》 2024年第10期963-974,共12页
Mining globally contributes to the growth of many economies of the world. Since its inception, the Zambian mining industry has contributed largely to the country’s economy. The various developments both in technology... Mining globally contributes to the growth of many economies of the world. Since its inception, the Zambian mining industry has contributed largely to the country’s economy. The various developments both in technology and knowledge have contributed to the scale at which mining is being done. Challenges in such a setting arise due to the socio-economic and environmental impacts of mining, which create multidimensional problems. The study investigated the importance of engaging stakeholders in progressive rehabilitation programs for large-scale open pit mines, using a case study of the Lumwana Mine and its host community, Manyama. A qualitative approach was used, and data was collected through one-on-one interviews. A combination of convenient and quota sampling was used to engage with host community leaders, professionals and academicians from various fields and institutions. Results showed that most participants had agreed that stakeholder engagement is important for progressive rehabilitation, but the challenge was that the host community and municipal council representatives were not aware of any progressive rehabilitation efforts at Lumwana Mine. This was attributed to a lack of stakeholder engagement and communication of mitigation progress activities by the Lumwana Mine. Results also revealed that the lack of environmental impact assessment regulations to compel companies to involve stakeholders throughout the entire life of the mine other than just at the pre-mining stage led to a lack of compliance and accountability in rehabilitation. 展开更多
关键词 Progressive Rehabilitation Stakeholder engagement Open Pit Environmental Impact
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The Influence of Academic Self-Efficacy on Learning Engagement in Online Education in China:The Mediating Role of Effort
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作者 Yan Zhang Zhicui Yao Jian Wang 《Journal of Contemporary Educational Research》 2024年第10期61-68,共8页
The shift towards online intelligent learning has become the norm in education and is now a fundamental part of modern educational activities.However,this new model can influence students’learning behavior and lead t... The shift towards online intelligent learning has become the norm in education and is now a fundamental part of modern educational activities.However,this new model can influence students’learning behavior and lead to changes in their approach to learning.Based on online intelligent learning,we investigated how the academic self-efficacy of nursing students affects their engagement with learning and explored the role of academic attribution as a mediator.Five hundred fifty-three nursing college students from Hebei and Hunan provinces in China participated in the online questionnaire.The results revealed that effort plays a mediating role in the relationship between academic self-efficacy and learning engagement. 展开更多
关键词 Academic self-efficacy Learning engagement Online learning Mediating role EFFORT
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Effects of Perceived Teacher Support on Student Behavioral Engagement in the Blended Learning Environment:Learning Experience as a Mediator
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作者 Yanle Zhang Peipei Chen +1 位作者 Suo Jiang Junjian Gao 《Journal of Contemporary Educational Research》 2024年第5期297-316,共20页
Blended learning(BL)has been widely adopted to improve students’academic achievements in higher education.However,its success relies mainly on student engagement,which plays an essential role in active learning and p... Blended learning(BL)has been widely adopted to improve students’academic achievements in higher education.However,its success relies mainly on student engagement,which plays an essential role in active learning and provides a rich understanding of students’experiences.The study utilized three self-designed scales-the Teacher Support Scale,Student Engagement Scale,and Student Learning Experience Scale-to gauge and examine the impact and relationship between perceived teacher support,student behavioral engagement,and the intermediary role of learning experiences.A cohort of 899 college students undertaking the obligatory College English course through BL modes across five Chinese universities actively participated by completing a comprehensive questionnaire.The results showed significant correlations between perceived teacher support,learning experience,and behavioral engagement.Perceived teacher support significantly predicted students’behavioral engagement,with socio-affective support exerting the most substantial predictive effects.All predictive effects were partially mediated by learning experience(learning mode,online resources,overall LMS-based learning,interaction with their instructor and peers,and learning outcome).The influence of perceived teacher support on behavioral engagement differed between students who reported the most positive(vs.negative)learning experiences.Suggestions for further research are offered for consideration. 展开更多
关键词 Student engagement Teacher support Learning experience Blended learning environment
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Leveraging Predictive Analytics for Strategic Corporate Communications: Enhancing Stakeholder Engagement and Crisis Management
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作者 Natalie Nkembuh 《Journal of Computer and Communications》 2024年第10期51-61,共11页
This study explores the integration of predictive analytics in strategic corporate communications, with a specific focus on stakeholder engagement and crisis management. Our mixed-methods approach, which combines a co... This study explores the integration of predictive analytics in strategic corporate communications, with a specific focus on stakeholder engagement and crisis management. Our mixed-methods approach, which combines a comprehensive literature review with case studies of five multinational corporations, allows us to investigate the applications, challenges, and ethical implications of leveraging predictive models in communication strategies. While our findings reveal significant potential for enhancing personalized content delivery, real-time sentiment analysis, and proactive crisis management, we stress the need for careful consideration of challenges such as data privacy concerns and algorithmic bias. This emphasis on ethical implementation is crucial in navigating the complex landscape of predictive analytics in corporate communications. To address these issues, we propose a framework that prioritizes ethical considerations. Furthermore, we identify key areas for future research, thereby contributing to the evolving field of data-driven communication management. 展开更多
关键词 Predictive Analytics Corporate Communications Stakeholder engagement Crisis Management Machine Learning Data-Driven Strategy Ethical AI Digital Transformation Reputation Management Strategic Communication
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Predictive roles of organizational and personal factors in work engagement among nurses 被引量:1
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作者 Charlie C.Falguera Leodoro J.Labrague +2 位作者 Janet Alexis A.De Los Santos Carmen N.Firmo Konstantinos Tsaras 《Frontiers of Nursing》 2022年第4期379-387,共9页
Objective:To determine the work engagement levels of hospital nurses and the predictive roles that nurses’personal and organizational characteristics play.Methods:A cross-sectional design was employed in this study,w... Objective:To determine the work engagement levels of hospital nurses and the predictive roles that nurses’personal and organizational characteristics play.Methods:A cross-sectional design was employed in this study,which included 549 nurses working in the Central Philippines.Nurses were selected through purposive sampling,and a self-repor t questionnaire outlining personal and organizational characteristics was employed.The Utrecht Work Engagement Scale(UWES)was applied to gather data about nurse engagement.Results:The dedication score was the highest among the three dimensions of engagement while the vigor score was the lowest.Overall,Filipino nurses experienced an average level of work engagement.We observed significant relationships between a nurse’s age,years of experience in nursing,years in their present unit,and their position at work and their levels of engagement,vigor,sense of dedication,and absorption.Hospital capacity was a negative predictor of vigor,dedication,absorption,and overall work engagement.Fur ther,the type of nursing contract was a negative predictor of vigor and dedication.The type of hospital and the nurse’s position were positive predictors of vigor,dedication,and absorption.Conclusions:Filipino nurses were satisfactorily engaged at work.A number of nurses’personal and organizational characteristics play a predictive role in their work engagement.Thus,nursing administrators must suppor t,develop,and implement activities and measures that engage nurses at work. 展开更多
关键词 Filipino nurses nurse personal factors organizational factors work engagement work engagement predictors
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Developing Engagement in the Learning Management System Supported by Learning Analytics
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作者 Suraya Hamid Shahrul Nizam Ismail +1 位作者 Muzaffar Hamzah Asad W.Malik 《Computer Systems Science & Engineering》 SCIE EI 2022年第7期335-350,共16页
Learning analytics is an emerging technique of analysing student par-ticipation and engagement.The recent COVID-19 pandemic has significantly increased the role of learning management systems(LMSs).LMSs previously only... Learning analytics is an emerging technique of analysing student par-ticipation and engagement.The recent COVID-19 pandemic has significantly increased the role of learning management systems(LMSs).LMSs previously only complemented face-to-face teaching,something which has not been possible between 2019 to 2020.To date,the existing body of literature on LMSs has not analysed learning in the context of the pandemic,where an LMS serves as the only interface between students and instructors.Consequently,productive results will remain elusive if the key factors that contribute towards engaging students in learning are notfirst identified.Therefore,this study aimed to perform an exten-sive literature review with which to design and develop a student engagement model for holistic involvement in an LMS.The required data was collected from an LMS that is currently utilised by a local Malaysian university.The model was validated by a panel of experts as well as discussions with students.It is our hope that the result of this study will help other institutions of higher learning determine factors of low engagement in their respective LMSs. 展开更多
关键词 engagement analysis learning analytics learning management system student engagement
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A Case Study of Employees' Engagement Practice in Corporate Responsibility Program
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《Economics World》 2017年第4期287-298,共12页
Organizational corporate social responsibility is a good practice by organizations. Organizations engagement in corporate social responsibility programs may benefit the organization and stakeholders. The focus of this... Organizational corporate social responsibility is a good practice by organizations. Organizations engagement in corporate social responsibility programs may benefit the organization and stakeholders. The focus of this paper is to explore the extent of employees' engagement in the organization's corporate responsibility programs by utilizing Unerman's (2007) stakeholders engagement framework. The main research question is how employees engage themselves in corporate social responsibility programs. This study employs a case study research design approach. The findings have shown that there is empowerment between employees and the management in the corporate social responsibility programs. Their involvement appears from their feedbacks and views in the surveys as well as discussion with regards to corporate responsibility programs. All in all, employees' engagement is seen as an important practice in the organization, particularly in planning, implementing, monitoring, and reporting the corporate responsibility program. 展开更多
关键词 corporate responsibility program stakeholders engagement employees engagement EMPOWERMENT acase research design approach MALAYSIA
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A review of foreign researches on influential factors affecting students' engagement in English classroom
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作者 ZHOU Chun-hong 《Sino-US English Teaching》 2010年第12期18-22,共5页
Students' active engagement constitutes the core of the process of learning and teaching in the student-oriented classroom. The paper centers on a review of foreign researches on influential factors affecting student... Students' active engagement constitutes the core of the process of learning and teaching in the student-oriented classroom. The paper centers on a review of foreign researches on influential factors affecting students' engagement in English classroom. It is expected to figure out the relevant factors in order to promote students' active engagement. 展开更多
关键词 students' engagement influential factors active engagement
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On Fashion’s Political Engagement in Modern Society
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作者 史亚娟 《语言与文化研究》 2020年第1期81-88,共8页
In class society,fashion is identified as a sign of class position and social status,while in modern democratic society fashion’s political connotation and significance have greatly changed and is mainly displayed fr... In class society,fashion is identified as a sign of class position and social status,while in modern democratic society fashion’s political connotation and significance have greatly changed and is mainly displayed from the following three aspects:1)as a way of social protest from vulnerable social groups by being symbol of being an independent and free subject.However,the resistance or protest represented by fashion is no more than something ritual.2)as a way of identity and subjectivity construction,both individual and national;3)as embodiment of fashion leadership and a way of incorporation.Generally to say,fashion has played an important role in every aspect above.However,there is still a tension between them and we must manage carefully to keep a balance. 展开更多
关键词 FASHION POLITICS engageMENT soft power
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Parametric Analysis of the End Face Engagement Worm Gear 被引量:11
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作者 DENG Xingqiao WANG Jueling +2 位作者 WANG Jinge CHEN Shouan YANG Jie 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第6期1177-1185,共9页
A novel specific type of worm drive, so-called end face engagement worm gear(EFEWD), is originally presented to minimize or overcome the gear backlash. Different factors, including the three different types, contact... A novel specific type of worm drive, so-called end face engagement worm gear(EFEWD), is originally presented to minimize or overcome the gear backlash. Different factors, including the three different types, contact curves, tooth profile, lubrication angle and the induced normal curvature are taken into account to investigate the meshing characteristics and create the profile of a novel specific type of worm drive through mathematical models and theoretical analysis. The tooth of the worm wheel is very specific with the sine-shaped tooth which is located at the alveolus of the worm and the tooth profile of a worm is generated by the meshing movement of the worm wheel with the sine-shaped tooth, but just the end face of the worm(with three different typical meshing types) is adapted to meshing, and therefore an extraordinary manufacturing methods is used to generate the profile of the end face engagement worm. The research results indicates that the bearing contacts of the generated conjugate hourglass worm gear set are in line contacts, with certain advantages of no-backlash, high precision and high operating efficiency over other gears and gear systems besides the end face engagement worm gear drive may improve bearing contact, reduce the level of transmission errors and lessen the sensitivity to errors of alignment. Also, the end face engagement worm can be easily made with superior meshing and lubrication performance compared with the conventional techniques. In particular, the meshing and lubrication performance of the end face engagement worm gear by using the end face to meshing can be increased over 10% and 7%, respectively. This investigate is expect to provide a new insight on the design of the future no-backlash worm drive for industry. 展开更多
关键词 worm drive end face engagement worm gear meshing characteristics anti-backlash.
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Optimal Design for an End Face Engagement Worm Gear with Multiple Worm-wheel Meshing 被引量:9
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作者 DENG Xingqiao ZHU Weibing +2 位作者 CHEN Yonghong CHEN Shouan WANG Jinge 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第1期144-151,共8页
To solve the problem for lacking a special mechanical transmission that could provide multiple outputs with high transmission efficiency and good lubrication in the modem industrial, a novel worm gear, named end face ... To solve the problem for lacking a special mechanical transmission that could provide multiple outputs with high transmission efficiency and good lubrication in the modem industrial, a novel worm gear, named end face engagement worm gear, with multiple worm-wheel meshing is proposed for the first time. The essential parameters for the worm gear are optimized to enhance lubrication and meshing properties. Moreover, analysis of variance(ANOVA) is applied to determine the optimum levels and to determine the influence of parameters. The ANOVA results show that the novel end face engagement worm gear with multiple worm wheels provides high lubrication(the lubrication angle is more than 89~) and meshing performance(the induce normal curvature is less than 0.0002 mm '). The interaction between center distance and roller slant distance most strongly influences the lubrication angle(contributed 51.6%), followed by the parameters of center distance(contributed 25.0%), roller slant distance(contributed 16.4%), tooth angle of gear, gear ratio, and roller radius. In addition, roller radius most strongly influences the induced normal curvature(contributed 39.4%), followed by roller slant distance(contributed 15.2%), tooth angle of the gear(contributed 9.0%), center distance, and gear ratio. The proposed worm gear helps to enrich the no-backlash high precision worm drive and the optimal design method can provide a useful reference on performance improvement of other worm gear. 展开更多
关键词 worm gear end face engagement worm optimization optimal design analysis of variance (ANOVA)
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Psychological capital mediates the association between nurses'practice environment and work engagement among Chinese male nurses 被引量:9
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作者 Xiaokang Pan Ting Mao +2 位作者 Jingping Zhang Jianjian Wang Pan Su 《International Journal of Nursing Sciences》 2017年第4期378-383,共6页
Objectives:This study aims to investigate the environmental and individual factors contributing to male nurses'psychological well-being and to explore the psychological mechanisms that may explain the links betwee... Objectives:This study aims to investigate the environmental and individual factors contributing to male nurses'psychological well-being and to explore the psychological mechanisms that may explain the links between nurses'practice environment and work engagement,thereby presenting the implications for nurse managers.Methods:A total of 161 male nurses from three tertiary first-class hospitals in Changsha City in China participated in the study.We collected the data using the Practice Environment Scale of the Nursing Work Index,the Psychological Capital Questionnaire,and the Utrecht Work Engagement Scale.Results:Scores of male nurses'practice environment(2.88±0.31),psychological capital(4.42±0.62),and work engagement(3.17±1.39)were all above the midpoint;however,the subscales"the nursing staffing and resources adequacy"(2.72±0.48),"hope"(4.33±0.72),and"dedication"(2.96±1.61)scored lowest.Nurses'practice environment and psychological capital positively predicted nurses'work engagement;psychological capital fully mediated the influence of nurses'practice environment on work engagement.Conclusions:Creating a supportive nursing practice environment can increase male nurses'work engagement by developing their psychological capital.Nurse managers can then provide reasonable workload and pathways for male nurses to achieve goals,thereby fostering their hope. 展开更多
关键词 Male nurses Nurses'practice environment Psychological capital Work engagement
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The mediating role of organizational commitment between calling and work engagement of nurses: A cross-sectional study 被引量:7
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作者 Yudi Cao Jingying Liu +2 位作者 Kejia Liu Mengyu Yang Yanhui Liu 《International Journal of Nursing Sciences》 CSCD 2019年第3期309-314,共6页
Objective: Nurse shortage is a critical problem for global healthcare services.It impacts the quality of clinical care.Work engagement is the core competence of hospitals,which indicates employee's positive attitu... Objective: Nurse shortage is a critical problem for global healthcare services.It impacts the quality of clinical care.Work engagement is the core competence of hospitals,which indicates employee's positive attitude toward organization and work.This study aimed to explore the relationships among calling,organizational commitment,and work engagement.Methods: A cross-sectional study was designed,and 320 nurses from tertiary hospitals in China completed the questionnaires that included demographic information,calling scale,employee engagement scale,and organizational commitment scale.Pearson correlation was performed to test the correlations among calling,organizational commitment,and work engagement.Stepwise regression analyses were performed to explore the mediating role of organizational commitment.The bootstrap method was employed to confirm the mediating effect.Results: Nurses' work engagement score was at the medium degree,whereas calling and organizational commitment were in the medium to high level.The results revealed that calling,organizational commitment,work engagement,and each dimension were positively correlated with one another (r=0.145-0.922,P < 0.01).The organizational commitment plays a partially mediating effect between calling and work engagement (β =0.603 to 0.333,P < 0.01).Conclusions: The mediation effect of organizational commitment was verified,which provided a comprehensive understanding of how calling impacted work engagement.Moreover,administrators should not only promote interventions to increase work engagement but also pay attention to calling and organizational commitment so as to improve their work engagement.Taken together,increased level of work engagement is required in the current nursing field. 展开更多
关键词 Nurses CALLING Employee engagement Organizational commitment
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Formation and adjustment of manned/unmanned combat aerial vehicle cooperative engagement system 被引量:18
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作者 ZHONG Yun YAO Peiyang +1 位作者 ZHANG Jieyong WAN Lujun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期756-767,共12页
Manned combat aerial vehicles (MCAVs), and un-manned combat aerial vehicles (UCAVs) together form a cooper-ative engagement system to carry out operational mission, whichwill be a new air engagement style in the n... Manned combat aerial vehicles (MCAVs), and un-manned combat aerial vehicles (UCAVs) together form a cooper-ative engagement system to carry out operational mission, whichwill be a new air engagement style in the near future. On the basisof analyzing the structure of the MCAV/UCAV cooperative engage-ment system, this paper divides the unique system into three hi-erarchical levels, respectively, i.e., mission level, task-cluster leveland task level. To solve the formation and adjustment problem ofthe latter two levels, three corresponding mathematical modelsare established. To solve these models, three algorithms calledquantum artificial bee colony (QABC) algorithm, greedy strategy(GS) and two-stage greedy strategy (TSGS) are proposed. Finally,a series of simulation experiments are designed to verify the effec-tiveness and superiority of the proposed algorithms. 展开更多
关键词 manned combat aerial vehicle (MCAV) unmannedcombat aerial vehicle (UCAV) cooperative engagement system quantum artificial bee colony (QABC) greedy strategy (GS) two-stage greedy strategy (TSGS)
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A Multi-UCAV cooperative occupation method based on weapon engagement zones for beyond-visual-range air combat 被引量:6
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作者 Wei-hua Li Jing-ping Shi +2 位作者 Yun-yan Wu Yue-ping Wang Yong-xi Lyu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第6期1006-1022,共17页
Recent advances in on-board radar and missile capabilities,combined with individual payload limitations,have led to increased interest in the use of unmanned combat aerial vehicles(UCAVs)for cooperative occupation dur... Recent advances in on-board radar and missile capabilities,combined with individual payload limitations,have led to increased interest in the use of unmanned combat aerial vehicles(UCAVs)for cooperative occupation during beyond-visual-range(BVR)air combat.However,prior research on occupational decision-making in BVR air combat has mostly been limited to one-on-one scenarios.As such,this study presents a practical cooperative occupation decision-making methodology for use with multiple UCAVs.The weapon engagement zone(WEZ)and combat geometry were first used to develop an advantage function for situational assessment of one-on-one engagement.An encircling advantage function was then designed to represent the cooperation of UCAVs,thereby establishing a cooperative occupation model.The corresponding objective function was derived from the one-on-one engagement advantage function and the encircling advantage function.The resulting model exhibited similarities to a mixed-integer nonlinear programming(MINLP)problem.As such,an improved discrete particle swarm optimization(DPSO)algorithm was used to identify a solution.The occupation process was then converted into a formation switching task as part of the cooperative occupation model.A series of simulations were conducted to verify occupational solutions in varying situations,including two-on-two engagement.Simulated results showed these solutions varied with initial conditions and weighting coefficients.This occupation process,based on formation switching,effectively demonstrates the viability of the proposed technique.These cooperative occupation results could provide a theoretical framework for subsequent research in cooperative BVR air combat. 展开更多
关键词 Unmanned combat aerial vehicle Cooperative occupation Beyond-visual-range air combat Weapon engagement zone Discrete particle swarm optimization Formation switching
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Autonomous Maneuver Decisions via Transfer Learning Pigeon-Inspired Optimization for UCAVs in Dogfight Engagements 被引量:7
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作者 Wanying Ruan Haibin Duan Yimin Deng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第9期1639-1657,共19页
This paper proposes an autonomous maneuver decision method using transfer learning pigeon-inspired optimization(TLPIO)for unmanned combat aerial vehicles(UCAVs)in dogfight engagements.Firstly,a nonlinear F-16 aircraft... This paper proposes an autonomous maneuver decision method using transfer learning pigeon-inspired optimization(TLPIO)for unmanned combat aerial vehicles(UCAVs)in dogfight engagements.Firstly,a nonlinear F-16 aircraft model and automatic control system are constructed by a MATLAB/Simulink platform.Secondly,a 3-degrees-of-freedom(3-DOF)aircraft model is used as a maneuvering command generator,and the expanded elemental maneuver library is designed,so that the aircraft state reachable set can be obtained.Then,the game matrix is composed with the air combat situation evaluation function calculated according to the angle and range threats.Finally,a key point is that the objective function to be optimized is designed using the game mixed strategy,and the optimal mixed strategy is obtained by TLPIO.Significantly,the proposed TLPIO does not initialize the population randomly,but adopts the transfer learning method based on Kullback-Leibler(KL)divergence to initialize the population,which improves the search accuracy of the optimization algorithm.Besides,the convergence and time complexity of TLPIO are discussed.Comparison analysis with other classical optimization algorithms highlights the advantage of TLPIO.In the simulation of air combat,three initial scenarios are set,namely,opposite,offensive and defensive conditions.The effectiveness performance of the proposed autonomous maneuver decision method is verified by simulation results. 展开更多
关键词 Autonomous maneuver decisions dogfight engagement game mixed strategy transfer learning pigeon-inspired optimization(TLPIO) unmanned combat aerial vehicle(UCAV)
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Trispecific killer engager 161519 enhances natural killer cell function and provides anti-tumor activity against CD19-positive cancers 被引量:3
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作者 Ying Cheng Xiaodong Zheng +5 位作者 Xuefu Wang Yongyan Chen Haiming Wei Rui Sun Zhigang Tian Haoyu Sun 《Cancer Biology & Medicine》 SCIE CAS CSCD 2020年第4期1026-1038,共13页
Objective:Natural killer(NK)cells have gained considerable attention due to their potential in treating"cold tumors,"and are therefore considered as one of the new strategies for curing cancer,by using world... Objective:Natural killer(NK)cells have gained considerable attention due to their potential in treating"cold tumors,"and are therefore considered as one of the new strategies for curing cancer,by using worldwide development of their new possibilities and interventions with NK cell-related therapeutic products.Methods:We constructed a trispecific killer engager(TriKE)consisting of anti-CD16,IL-15,and anti-CD19.This TriKE was designed to attract CD19^(+)tumor cells to CD16^(+)NK cells,whereas IL-15 sustained the proliferation,development,and survival of NK cells.Results:Treatment with 161519 TriKE in the presence of CD19^(+)targets upregulated expression of CD69,CD107 a,TRAIL,IFN-γ,and TNF-α in NK cells,and significantly improved the proliferation and cytotoxicity of NK cells.NK cells"armed"with 161519 TriKE showed stronger cytolysis against CD19+targets compared with that of"unarmed"NK cells.A preclinical model of B-cell lymphoma in human peripheral blood mononuclear cell-reconstituted xenograft mice showed significant inhibition of tumor growth and prolonged overall survival after treatment with 161519 TriKE,when compared with that in control mice or mice treated with 1619 BiKE.Combined use of IL-2 was a more effective treatment with 1619 BiKE,when compared with that using 161519 TriKE.Conclusions:The newly generated 161519 TriKE enhanced the proliferation,activation,cytokine secretion,and cytotoxicity of NK cells in the presence of CD19+tumor cells.The 161519 TriKE aided inhibition of tumor growth and prolonged the overall survival of murine xenografts,and could be used to treat CD19-positive cancers. 展开更多
关键词 Trispecific antibody trispecific killer engager(TriKE) NK cell B-cell lymphoma tumor immunotherapy
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