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Return to work in young and middle-aged colorectal cancer survivors:Factors influencing self-efficacy,fear,resilience,and financial toxicity
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作者 Dan Hu Yue Li +6 位作者 Hua Zhang Lian-Lian Wang Wen-Wen Liu Xin Yang Ming-Zhao Xiao Hao-Ling Zhang Juan Li 《World Journal of Gastroenterology》 SCIE CAS 2025年第1期79-92,共14页
BACKGROUND Return to work(RTW)serves as an indication for young and middle-aged colorectal cancer(CRC)survivors to resume their normal social lives.However,these survivors encounter significant challenges during their... BACKGROUND Return to work(RTW)serves as an indication for young and middle-aged colorectal cancer(CRC)survivors to resume their normal social lives.However,these survivors encounter significant challenges during their RTW process.Hence,scientific research is necessary to explore the barriers and facilitating factors of returning to work for young and middle-aged CRC survivors.AIM To examine the current RTW status among young and middle-aged CRC survivors and to analyze the impact of RTW self-efficacy(RTW-SE),fear of progression(FoP),eHealth literacy(eHL),family resilience(FR),and financial toxicity(FT)on their RTW outcomes.METHODS A cross-sectional investigation was adopted in this study.From September 2022 to February 2023,a total of 209 participants were recruited through a convenience sampling method from the gastrointestinal surgery department of a class A tertiary hospital in Chongqing.The investigation utilized a general information questionnaire alongside scales assessing RTW-SE,FoP,eHL,FR,and FT.To analyze the factors that influence RTW outcomes among young and middle-aged CRC survivors,Cox regression modeling and Kaplan-Meier survival analysis were used.RESULTS A total of 43.54%of the participants successfully returned to work,with an average RTW time of 100 days.Cox regression univariate analysis revealed that RTW-SE,FoP,eHL,FR,and FT were significantly different between the non-RTW and RTW groups(P<0.05).Furthermore,Cox regression multivariate analysis identified per capita family monthly income,job type,RTW-SE,and FR as independent influencing factors for RTW(P<0.05).CONCLUSION The RTW rate requires further improvement.Elevated levels of RTW-SE and FR were found to significantly increase RTW among young and middle-aged CRC survivors.Health professionals should focus on modifiable factors,such as RTW-SE and FR,to design targeted RTW support programs,thereby facilitating their timely reintegration into mainstream society. 展开更多
关键词 Return to work Colorectal neoplasms Return-to-work self-efficacy Fear of progression Family resilience Financial toxicity
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基于InfoWorks ICM水力模型的排水管道负荷分析方法
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作者 张辰 《工程建设与设计》 2025年第2期31-33,共3页
采用InfoWorks ICM水力模型,通过构建量化模型,对排水管道在不同降雨强度条件下的负荷进行分析。结果表明,新建雨水系统能满足5年一遇降雨标准,且在10年一遇降雨标准下,路面积水不超150 mm。
关键词 排水管道 负荷分析 Info works ICM 管道沉积物
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Labor Motivation and Its Influence on Workers’Productivity-A Secondary Publication
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作者 Ricardo Molinar 《Proceedings of Business and Economic Studies》 2024年第1期210-217,共8页
The productivity of an institution is achieved,in large part,by creating a harmonious environment that reflects the satisfaction,empowerment,and collaborative spirit of each employee.From this perspective,management w... The productivity of an institution is achieved,in large part,by creating a harmonious environment that reflects the satisfaction,empowerment,and collaborative spirit of each employee.From this perspective,management will consider upgrades using all tactics that allow for the achievement of these goals,including direct effort and the involvement of all stakeholders.The objective of this study was to examine the relationship between work motivation and the productivity of workers in the communal board of the Barrio Sur corregimiento in the province of Colón.Using the questionnaire as an instrument,as well as the descriptive method,allowed for the report and evaluation of the characteristics of the workers,indicating interpersonal deficits and distancing in the motivations that drive administrative action.By incorporating different approaches previously analyzed and developed by different authors familiar with the subject,it was possible to achieve substantial results,such as the need to implement administrative strategies that harmoniously incorporate workers,showing that,despite motivation problems,the work environment where one works is very important in the performance of their duties.Managing to motivate the direct participation of the workers selected as part of the sample,who showed full satisfaction with the results framed within the framework of individual improvement and,above all,the commitment to the institution to improve its work. 展开更多
关键词 work motivation PRODUCTIVITY workers work environment
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Flow characteristics and hot workability of a typical low-alloy high-strength steel during multi-pass deformation 被引量:2
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作者 Mingjie Zhao Lihong Jiang +4 位作者 Changmin Li Liang Huang Chaoyuan Sun Jianjun Li Zhenghua Guo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期323-336,共14页
Heavy components of low-alloy high-strength(LAHS) steels are generally formed by multi-pass forging. It is necessary to explore the flow characteristics and hot workability of LAHS steels during the multi-pass forging... Heavy components of low-alloy high-strength(LAHS) steels are generally formed by multi-pass forging. It is necessary to explore the flow characteristics and hot workability of LAHS steels during the multi-pass forging process, which is beneficial to the formulation of actual processing parameters. In the study, the multi-pass hot compression experiments of a typical LAHS steel are carried out at a wide range of deformation temperatures and strain rates. It is found that the work hardening rate of the experimental material depends on deformation parameters and deformation passes, which is ascribed to the impacts of static and dynamic softening behaviors. A new model is established to describe the flow characteristics at various deformation passes. Compared to the classical Arrhenius model and modified Zerilli and Armstrong model, the newly proposed model shows higher prediction accuracy with a confidence level of 0.98565. Furthermore, the connection between power dissipation efficiency(PDE) and deformation parameters is revealed by analyzing the microstructures. The PDE cannot be utilized to reflect the efficiency of energy dissipation for microstructure evolution during the entire deformation process, but only to assess the efficiency of energy dissipation for microstructure evolution in a specific deformation parameter state.As a result, an integrated processing map is proposed to better study the hot workability of the LAHS steel, which considers the effects of instability factor(IF), PDE, and distribution and size of grains. The optimized processing parameters for the multi-pass deformation process are the deformation parameters of 1223–1318 K and 0.01–0.08 s^(-1). Complete dynamic recrystallization occurs within the optimized processing parameters with an average grain size of 18.36–42.3 μm. This study will guide the optimization of the forging process of heavy components. 展开更多
关键词 low-alloy high-strength steel work hardening rate constitutive model hot workability multi-pass deformation
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UAV-assisted data collection for wireless sensor networks with dynamic working modes 被引量:1
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作者 Jie Chen Jianhua Tang 《Digital Communications and Networks》 SCIE CSCD 2024年第3期805-812,共8页
Wireless Sensor Network(WSN)is a cornerstone of Internet of Things(IoT)and has rich application scenarios.In this work,we consider a heterogeneous WSN whose sensor nodes have a diversity in their Residual Energy(RE).I... Wireless Sensor Network(WSN)is a cornerstone of Internet of Things(IoT)and has rich application scenarios.In this work,we consider a heterogeneous WSN whose sensor nodes have a diversity in their Residual Energy(RE).In this work,to protect the sensor nodes with low RE,we investigate dynamic working modes for sensor nodes which are determined by their RE and an introduced energy threshold.Besides,we employ an Unmanned Aerial Vehicle(UAV)to collect the stored data from the heterogeneous WSN.We aim to jointly optimize the cluster head selection,energy threshold and sensor nodes’working mode to minimize the weighted sum of energy con-sumption from the WSN and UAV,subject to the data collection rate constraint.To this end,we propose an efficient search method to search for an optimal energy threshold,and develop a penalty-based successive convex approximation algorithm to select the cluster heads.Then we present a low-complexity iterative approach to solve the joint optimization problem and discuss the implementation procedure.Numerical results justify that our proposed approach is able to reduce the energy consumption of the sensor nodes with low RE significantly and also saves energy for the whole WSN. 展开更多
关键词 Unmanned aerial vehicle Wireless sensor networks Cluster heads Dynamic working modes
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Work Condition and Health at a Body Paint Workshop in Conakry
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作者 Yansane Alhousseine Koffi Cyrille +3 位作者 Bah Mamadou Condé Namoudou Bah Hassane Mara Ansoumane 《Occupational Diseases and Environmental Medicine》 2024年第4期298-304,共7页
Context: Working conditions in the car repair sector are difficult in general. This leads to health risk factors for inexperienced staff. In the bodywork painting workshop, the staff seemed less interested in the risk... Context: Working conditions in the car repair sector are difficult in general. This leads to health risk factors for inexperienced staff. In the bodywork painting workshop, the staff seemed less interested in the risks probably due to negligence or by lack of knowledge. This work aimed to describe the working conditions and their impact on the workers’ health in a workshop of bodywork painting in Conakry. Material and Methods: This was a cross-sectional study over 06 months (from July 01, 2021, to December 31, 2021). Were included the bodybuilders-painters, the painters and the bodybuilders. The data was collected during an interview. We analysed the personal data of the workers, the physical environment factors (lighting, noise, etc.) and, the clinical manifestations felt by the workers. Results: The average age was 37 years extenting from 18 to 54 years and, they were all men. Over 80% of workers were exposed to more than 1000 lux and, 78.2% of workers were exposed to the vibratory intensity level of the cordless drill > 2.5 m/s2. The most frequent symptoms were back pain, headache, itchy eyes, and numbness of fingers and hands. The analysis of working conditions and clinical manifestations showed a significant relationship between the level of illumination and the tingling eyes (p = 0.0007), the vibratory intensity of the drill and the numbness of fingers and hands (p = 0.01). This study revealed that some of the complaints cited are related to the working conditions. Conclusion: Working conditions in a bodywork paint workshop are occupational risk factors that become dangerous if they are unknown. A longitudinal study on the assessment of working conditions could better enlighten us on this phenomenon. 展开更多
关键词 working Conditions Bodywork-Painting Conakry HEALTH
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Determinants of Satisfaction at Work and Its Reflections on Performance
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作者 Giovani Luiz Garcia Costantini Everton Anger Cavalheiro +2 位作者 Larissa Medianeira Bolzan Alejandro Martins Rodrigues Luíza Roloff Falck 《Chinese Business Review》 2024年第1期24-36,共13页
This study examines the relationship between job satisfaction and performance,investigating personality traits and satisfaction aspects among employees of a Federal Higher Education Institution.A questionnaire was adm... This study examines the relationship between job satisfaction and performance,investigating personality traits and satisfaction aspects among employees of a Federal Higher Education Institution.A questionnaire was administered to 658 participants,using structural equation modeling for analysis.Results highlighted that challenging work,neuroticism,and self-esteem significantly influenced overall workplace satisfaction,while general satisfaction,self-efficacy,and lack of attention were key determinants of work performance.This emphasizes the importance for managers to prioritize factors enhancing employee satisfaction,as it positively correlates with job performance. 展开更多
关键词 satisfaction at work work performance personality traits facets of job satisfaction Federal Higher Education Institution
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Suggested Work Modifications for Patients with Environmental and Occupational Risk Factors in Hidradenitis Suppurativa
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作者 Kelly Frasier Mary Grace Hash +3 位作者 Alyssa Forsyth Christina Randolph Guang Orestes Raquel Batista 《Occupational Diseases and Environmental Medicine》 2024年第4期305-317,共13页
Hidradenitis suppurativa (HS) is a chronic, inflammatory skin condition characterized by painful nodules, abscesses, and scarring, primarily affecting areas rich in apocrine glands. Environmental and occupational risk... Hidradenitis suppurativa (HS) is a chronic, inflammatory skin condition characterized by painful nodules, abscesses, and scarring, primarily affecting areas rich in apocrine glands. Environmental and occupational risk factors, including prolonged exposure to heat, friction, and certain chemicals, have been identified as exacerbating conditions for HS. Yet, there remains a lack of tailored recommendations for modifying work environments to alleviate these triggers. This review presents novel suggestions for work modifications to reduce HS flare-ups, such as implementing breathable, friction-reducing workwear, ergonomic adjustments to minimize pressure on affected areas, and introducing low-irritant hygiene protocols in workplaces with chemical exposure. These recommendations are grounded in emerging evidence linking specific occupational exposures to the exacerbation of HS symptoms. The novelty of this approach lies in its proactive stance, shifting from reactive management of HS symptoms to preventative environmental modifications. Future studies should explore the long-term efficacy of these modifications and investigate the potential for personalized work environment adjustments based on individual patient profiles. Targeted workplace interventions may significantly improve the quality of life for HS patients, highlighting the need for multidisciplinary collaboration between dermatologists, occupational health specialists, and employers. 展开更多
关键词 Hidradenitis Suppurativa Occupational Risk Factors work Environment Modifications Heat and Friction Exposure Ergonomic Adjustments Chemical Irritants Preventative Strategies workwear for HS Environmental Triggers Dermatology and Occupational Health Collaboration
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Prevalence of Work-Aggravated Asthma among Bakery Workers in Abidjan (Cote d’Ivoire)
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作者 Loukou Leandre Konan Esme Marie Laure Essis +5 位作者 Brou Michel Kouassi Marius Kedote Julius Fobil William Yavo Ossey Bernard Yapo Issaka Tiembre 《Health》 2024年第3期204-217,共14页
Introduction: Work-aggravated asthma is pre-existing or concomitant asthma whose symptoms are aggravated by the work environment. The aim of this study was to determine the prevalence of this pathology and its associa... Introduction: Work-aggravated asthma is pre-existing or concomitant asthma whose symptoms are aggravated by the work environment. The aim of this study was to determine the prevalence of this pathology and its associated factors among bakery workers in Abidjan. Materials and Methods: This descriptive and analytical cross-sectional study was conducted over a period of four (4) months from 18 December 2019 to 18 April 2020. Two questionnaires were used, one on employees and the other on the indoor environment of bakeries. In addition, a spirometry test was performed on all bakery workers. Statistical analysis was performed using stata 15.1 software. Results: A total of 599 bakery employees, including bakers (59.73%), sales assistants/ cashiers (23.52%), cleaners (6.34%) and administrative staff (10.18%), were investigated. The mean age was 30.8 ± 8 years, with a sex ratio (M/F) = 2.2. Asthma symptoms were found in 95 (15.86%) employees, of whom 74 (77.9%) had work-related asthma and 11 (14.9%) had asthma aggravated by work. The factors associated with work-aggravated asthma were personal or family history of allergy or atopy [ORa = 3.75;CI95%: 1.56 - 8.93;p = 0.003], exposure to dust [ORa = 5.01;CI95%: 1.43 - 7.50;p = 0.011] and humidity level (60% - 70%) [ORa = 1.80;CI 95%: 0.99 - 3.28;p = 0.05]. Conclusion: Work-aggravated asthma is a reality in bakeries in Abidjan, with an estimated prevalence of 14.9%. Two of the three factors associated with this condition suggest a link with indoor air pollution. Combating air pollution in these establishments must therefore be a priority for the relevant authorities, in order to provide employees with a working environment that protects their health. 展开更多
关键词 work-Aggravated Asthma Occupational Asthma work-Related Asthma BAKERIES ABIDJAN Ivory Coast
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Work Ability Index and Work Ability Score: A Comparation between both Scores in a Persistent COVID-19 Cohort
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作者 Carmen Muñoz-Ruiperez Diego Alvaredo Rodrigo +3 位作者 Daniel Arroyo-Sánchez Juan Francisco Álvarez Zarallo Ignacio Sánchez-Arcilla Conejo José Lorenzo Bravo Grande 《Occupational Diseases and Environmental Medicine》 2024年第1期49-57,共9页
Aims: The present study aims to compare the assessment of work ability based on the use of the Work Ability Index (WAI) with another questionnaire base only on the use of WAI’s first item, termed as the “Work Abilit... Aims: The present study aims to compare the assessment of work ability based on the use of the Work Ability Index (WAI) with another questionnaire base only on the use of WAI’s first item, termed as the “Work Ability Score” (WAS). Study design: A cohort of 384 Spanish workers included in a Post COVID-19 condition or persistent COVID-19 multicenter research was utilized. Place and Duration of Study: This cohort was enlisted in four hospitals (Hospital Universitario 12 de Octubre, Madrid;Hospital Universitario Virgen Macarena, Sevilla, Andalucía;Hospital Universitario Gregorio Marañón, Madrid and Complejo Asistencial Universitario de Salamanca, Castilla y León), since 2021 until 2022. Methodology: 384 Spanish workers (176 men and 208 women;aged 20 to 70 years) with Post COVID-19 condition or persistent COVID-19 were included. Descriptive analysis of primary scores was conducted. Given the non-normal distribution of data, the Mann-Whitney and Kruskal-Wallis tests were employed. Spearman and Kendall correlations were employed to assess the relationship between WAI and WAS, also used weighted Kappa to estimate the degree agreement between WAI and WAS. Logistic regression models were utilized to study determinants influencing WAI and WAS, categorized as poor or moderate. Results: WAI had an average score of 32.98 (SD = 10.28), whereas WAS had an average of 5.95 (SD = 2.77). Significant differences were observed in both WAI and WAS across the same variables. Strong and statistically significant correlations were evident between WAI and WAS (rs = 0.83, p < 0.001). All the variables used in the logistic regression model (gender, the sector employment, and previous chronic diseases) were statistically significant in both questionnaires. Conclusion: WAS questionnaire could be used as a tool for reliable assessment of work ability among Spanish workers with Post COVID-19 condition or Persistent CO-VID-19. 展开更多
关键词 work Ability Index work Ability Score Post COVID-19 Condition Occupational Health Occupational Medicine
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Evolution of Disabled Persons' Telework Management in Business
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作者 Karolina Karbownik 《Management Studies》 2017年第4期361-369,共9页
The theme of the foregoing is evolution in the management of telework. In addition, seeking the answer to the question: what is working and how to change the model of personnel management in telework? To find the an... The theme of the foregoing is evolution in the management of telework. In addition, seeking the answer to the question: what is working and how to change the model of personnel management in telework? To find the answers to these questions, the author conducted a survey of managers of this type. In addition, research shows that management system has evolved significantly. And although still requirement changes, the activities are quite flexible, and adapted to the staff. 展开更多
关键词 mobile work TELEworkING disabled persons permanent telework alternating telework supplementarytelework
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Use of cognitive-behavioral career coaching to reduce work anxiety and depression in public employees 被引量:1
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作者 Mkpoikanke Sunday Otu Maximus Monaheng Sefotho 《World Journal of Clinical Cases》 SCIE 2024年第2期322-334,共13页
BACKGROUND Public employees worldwide are increasingly concerned about work anxiety and depression.Cognitive-behavioral career coaching has emerged as a promising strategy for addressing these mental health disorders,... BACKGROUND Public employees worldwide are increasingly concerned about work anxiety and depression.Cognitive-behavioral career coaching has emerged as a promising strategy for addressing these mental health disorders,which can negatively impact on a person's overall well-being and performance.AIM To examine whether cognitive-behavioral career coaching reduces work anxiety and depression among Nigerian public employees.METHODS A total of 120 public employees(n=60)suffering from severe anxiety and depression were randomly assigned to the treatment or control groups in this study.Cognitive behavioral coaching was provided twice a week to those in the treatment group,whereas no treatment was given to those in the control group.As part of the study,the Hamilton Anxiety Rating Scales and Beck Depression Inventory were used to collect data.RESULTS Analysis of covariance of the data from participants indicates a significant effect of cognitive-behavioral career coaching on work anxiety and depression.CONCLUSION Insights into the underlying mechanisms by which cognitive behavior career coaching exerts its effects have been gained from this study.Also,the study has gathered valuable data that can inform future practice and guide the development of strategies for supporting mental health at work. 展开更多
关键词 Cognitive-behavioral career coaching work anxiety Depression Public employees North Central Nigeria
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On Answering the Question Related to the Legal Regulation of Working Hours in the New Era:Western Experience and Chinese Approach
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作者 曹燕 XU Chao 《The Journal of Human Rights》 2023年第1期157-181,共25页
The popularity of flexible working hours around the world has slowed down the historical trend of reducing working hours.It even shows signs of regression.Whether and how to guide the cur-rent society with flexible wo... The popularity of flexible working hours around the world has slowed down the historical trend of reducing working hours.It even shows signs of regression.Whether and how to guide the cur-rent society with flexible working hours to return to the historical track of reducing working hours,improve the quality of working hours,and promote a smooth transition from the era of traditional standard work-ing hours to the era of flexible working hours has become a question related to the legal regulation of working hours in the new era.In this regard,although Western countries have proposed new regulatory concepts and carried out legislative practices with distinctive charac-teristics,the limitations of legal regulation capabilities have prevented them from proposing a package of institutional solutions.The advan-tage of China in the ability of legal regulation of working hours has been gradually formed in the legislation on working hours unnder the leadership of the CPC in the past century.It enables China to break through the limitations of the West and propose a Chinese approach to answer the question of the legal regulation of working hours in the new era from three aspects:limiting the extension of working hours,improving the quality of flexible working hours,and optimizing the funnctions of the multi-funnctional regulatory system for working hours. 展开更多
关键词 question related to the legal regulation of working hours in the new era flexible working hours Chinese approach decent working hours quality of working hours working hours capability balanced working hours
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Social Work as a Research-Based Profession: Opportunities, Prerequisites and Restrictions 被引量:2
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作者 Juha Hamalainen 《Sociology Study》 2011年第7期473-483,共11页
The concept of research-based social work is introduced and discussed from the point of view of preconditions for its realization. Attention is paid both to the academic research of social work and to opportunities fo... The concept of research-based social work is introduced and discussed from the point of view of preconditions for its realization. Attention is paid both to the academic research of social work and to opportunities for developing a knowledge-producing social work practice. Both of these are seen as essential elements of a research-based profession. On the one hand, the academic research is necessary for development of social work as a research-based professional system, and on the other hand, a knowledge-producing practice, conducted by research-oriented practitioners, can only be realized within such a system. Historically, social work has been partly developed as a knowledge-applying instead of a knowledge-producing profession, although the central founding pioneers emphasized the importance of an own-knowledge basis and theory formation, as well as the idea of knowledge-producing practice based on a corresponding professional identity. The future of social work as a professional system in modern society may depend decisively on how it develops a research-based professional identity, not only in the sense of academic research but also through practitioners with research orientation. These are practitioners who would be capable of research-based working in terms of creative knowledge production, thus of developing social work as a credible research-based profession. This can be created only through education in which the development of necessary professional skills is linked to advanced academic meta-skills. There are good reasons to suspect that a three-year education is too short for this. 展开更多
关键词 Social work profession research-based social work education of social work social work practice
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Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning
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作者 Yun-Peng He Hai-Bo Cheng +4 位作者 Peng Zeng Chuan-Zhi Zang Qing-Wei Dong Guang-Xi Wan Xiao-Ting Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期641-653,共13页
High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well operations.Deep learning-based method for classifying the dynamometer card(DC)of oil wells is an eff... High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well operations.Deep learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis method.However,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational effort.Additionally,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different moments.Thus,there is heterogeneity in field data,which can dramatically impair the diagnostic accuracy.To solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this paper.First,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC data.Subsequently,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data heterogeneity.Finally,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the 4S-TFSM.Experiments on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational cost.To the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS. 展开更多
关键词 Sucker-rod pumping system Dynamometer card working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix
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Design and optimization of fluid lubricated bearings operated with extreme working performances——a comprehensive review
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作者 Guohua Zhang Ming Huang +6 位作者 Gangli Chen Jiasheng Li Yang Liu Jianguo He Yueqing Zheng Siwei Tang Hailong Cui 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期325-376,共52页
Fluid lubricated bearings have been widely adopted as support components for high-end equipment in metrology,semiconductor devices,aviation,strategic defense,ultraprecision manufacturing,medical treatment,and power ge... Fluid lubricated bearings have been widely adopted as support components for high-end equipment in metrology,semiconductor devices,aviation,strategic defense,ultraprecision manufacturing,medical treatment,and power generation.In all these applications,the equipment must deliver extreme working performances such as ultraprecise movement,ultrahigh rotation speed,ultraheavy bearing loads,ultrahigh environmental temperatures,strong radiation resistance,and high vacuum operation,which have challenged the design and optimization of reliable fluid lubricated bearings.Breakthrough of any related bottlenecks will promote the development course of high-end equipment.To promote the advancement of high-end equipment,this paper reviews the design and optimization of fluid lubricated bearings operated at typical extreme working performances,targeting the realization of extreme working performances,current challenges and solutions,underlying deficiencies,and promising developmental directions.This paper can guide the selection of suitable fluid lubricated bearings and optimize their structures to meet their required working performances. 展开更多
关键词 fluid lubricated bearings structural design performance optimization extreme working performances
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The action mechanism of the work done by the electric field force on moving charges to stimulate the emergence of carrier generation/recombination in a PN junction
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作者 Lingyun GUO Yizhan YANG +1 位作者 Wanli YANG Yuantai HU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期1001-1014,共14页
It is discovered that the product of the current and the electric field in a PN junction should be regarded as the rate of work(power)done by the electric field force on moving charges(hole current and electron curren... It is discovered that the product of the current and the electric field in a PN junction should be regarded as the rate of work(power)done by the electric field force on moving charges(hole current and electron current),which was previously misinterpreted as solely a Joule heating effect.We clarify that it is exactly the work done by the electric field force on the moving charges to stimulate the emergence of non-equilibrium carriers,which triggers the novel physical phenomena.As regards to Joule heat,we point out that it should be calculated from Ohm’s law,rather than simply from the product of the current and the electric field.Based on this understanding,we conduct thorough discussion on the role of the electric field force in the process of carrier recombination and carrier generation.The thermal effects of carrier recombination and carrier generation followed are incorporated into the thermal equation of energy.The present study shows that the exothermic effect of carrier recombination leads to a temperature rise at the PN interface,while the endothermic effect of carrier generation causes a temperature reduction at the interface.These two opposite effects cause opposite heat flow directions in the PN junction under forward and backward bias voltages,highlighting the significance of managing device heating phenomena in design considerations.Therefore,this study possesses referential significance for the design and tuning on the performance of piezotronic devices. 展开更多
关键词 piezoelectric semiconductor(PS) work done by electric field force thermal effect piezotronic device resistivity conductivity
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Correlation of work function and stacking fault energy through Kelvin probe force microscopy and nanohardness in diluteα-magnesium
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作者 Yigit Türe Ali Arslan Kaya +2 位作者 Hüseyin Aydin Jiang Peng Servet Turan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期237-250,共14页
Electronic interactions of the Group 2A elements with magnesium have been studied through the dilute solid solutions in binary Mg-Ca,Mg-Sr and Mg-Ba systems.This investigation incorporated the difference in the‘Work ... Electronic interactions of the Group 2A elements with magnesium have been studied through the dilute solid solutions in binary Mg-Ca,Mg-Sr and Mg-Ba systems.This investigation incorporated the difference in the‘Work Function'(ΔWF)measured via Kelvin Probe Force Microscopy(KPFM),as a property directly affected by interatomic bond types,i.e.the electronic structure,nanoindentation measurements,and Stacking Fault Energy values reported in the literature.It was shown that the nano-hardness of the solid-solutionα-Mg phase changed in the order of Mg-Ca>Mg-Sr>Mg-Ba.Thus,it was shown,by also considering the nano-hardness levels,that SFE of a solid-solution is closely correlated with its‘Work Function'level.Nano-hardness measurements on the eutectics andΔWF difference between eutectic phases enabled an assessment of the relative bond strength and the pertinent electronic structures of the eutectics in the three alloys.Correlation withΔWF and at least qualitative verification of those computed SFE values with some experimental measurement techniques were considered important as those computational methods are based on zero Kelvin degree,relatively simple atomic models and a number of assumptions.As asserted by this investigation,if the results of measurement techniques can be qualitatively correlated with those of the computational methods,it can be possible to evaluate the electronic structures in alloys,starting from binary systems,going to ternary and then multi-elemental systems.Our investigation has shown that such a qualitative correlation is possible.After all,the SFE values are not treated as absolute values but rather become essential in comparative investigations when assessing the influences of alloying elements at a fundamental level,that is,free electron density distributions.Our study indicated that the principles of‘electronic metallurgy'in developing multi-elemental alloy systems can be followed via practical experimental methods,i.e.ΔWF measurements using KPFM and nanoindentation. 展开更多
关键词 Mg alloys Dilute alloys work function Stacking fault energy Kelvin probe force microscopy Short range order Miedema NANOINDENTATION EUTECTICS
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基于SolidWorks的导线卡线器三维建模及运动仿真 被引量:1
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作者 杨文雄 曾德惠 +2 位作者 刘璐 胡宁丹 刘桂花 《机械管理开发》 2024年第4期11-13,共3页
为解决导线挂线时的滑线、跑线问题,提高卡线器的设计效率,通过分析卡线器的结构和工作原理,以SKLT-60卡线器为主要研究对象,基于三维软件SolidWorks及其Motion插件,进行零件建模、虚拟装配及运动仿真,得到卡线器的夹嘴夹持力、上夹嘴... 为解决导线挂线时的滑线、跑线问题,提高卡线器的设计效率,通过分析卡线器的结构和工作原理,以SKLT-60卡线器为主要研究对象,基于三维软件SolidWorks及其Motion插件,进行零件建模、虚拟装配及运动仿真,得到卡线器的夹嘴夹持力、上夹嘴运动轨迹、摇杆极限位置及滑块行程随时间的变化曲线.仿真结果表明:夹嘴夹持力、传动角及拉环行程满足设计要求.将虚拟样机技术和运动仿真技术相结合,对卡线器进行仿真分析,具有较好的模拟效果,缩短了产品开发周期,还能根据仿真结果进行结构优化,为类似设计提供了一种快捷、可靠的方法. 展开更多
关键词 导线卡线器 SOLIDworkS 三维建模 虚拟装配 运动仿真
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Formulation of Work-Study Combined and Result-Oriented Integrated Curriculum Standards
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作者 Lianfang LI Chunhua DU +2 位作者 Fen YANG Yun LI Yanfei NIU 《Medicinal Plant》 2024年第3期79-83,共5页
According to the Annex Technical Regulations for Integrated Curriculum Development(Trial)in Document No.30 of the General Office of the Ministry of Human Resources and Social Security(2012),this paper studies the form... According to the Annex Technical Regulations for Integrated Curriculum Development(Trial)in Document No.30 of the General Office of the Ministry of Human Resources and Social Security(2012),this paper studies the formulation of the curriculum standards for the integration of Chinese medicinal materials production.We focus on the formulation ideas of the curriculum standards for the integration of Chinese medicinal materials production,the formulation process of the curriculum standards for the integration of Chinese medicinal materials production,including the description of typical work tasks,the determination of curriculum objectives,the analysis of study content,the description of referential study tasks,teaching implementation suggestions,assessment and evaluation suggestions,which can provide a reference for the development and research of other related integrated courses. 展开更多
关键词 Integration of work and STUDY work process Curriculum STANDARDS Production of Chinese MEDICINAL materials Typical work TASKS REFERENTIAL STUDY TASKS
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