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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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Challenges in Work-Family Balance and Support Needs of Japanese Parents with Nursery School-Aged Children
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作者 Yuko Shimoda Miyuki Ishii Yuichi Hori 《Health》 2023年第6期622-639,共18页
We aimed to identify the challenges parents face raising preschool-aged children when trying to maintain a good work-family balance. We also highlight how public health nurses can support the community in this regard.... We aimed to identify the challenges parents face raising preschool-aged children when trying to maintain a good work-family balance. We also highlight how public health nurses can support the community in this regard. Seven Japanese parents volunteered to participate, and individual in-depth interviews were conducted from May to October 2021. We analyzed the recorded interview data using qualitative descriptive methods. Three main themes concerning work-family balance challenges were extracted: 1) conflicts between parents’ childcare and work roles, 2) issues related to institutions and social systems, and 3) a lack of informal support. Factors contributing to the difficulties were a lack of time to spend with their children;an imbalance in the division of housework and childcare roles between married couples;the employment environment in Japan that makes it difficult to pursue a career while raising children;a lack of childcare services, including childcare for sick children;inadequate consultation systems;and an aging grandparents’ generation owing to late marriages. To solve this problem, we suggest that in addition to establishing a reliable system for providing childcare, local public health nurses should work with childcare workers to create an environment in which parents feel comfortable discussing work-family balance, considering the time constraints of parents during the childrearing period, and use nursery schools as a place for parent-child support. 展开更多
关键词 Childrearing PARENT Public Health Nurse work-Family Balance
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Epidemiological Patterns of Work-Related Musculoskeletal Disorders among Healthcare Workers in Five Reference Hospitals in the City of Douala, Cameroon
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作者 Basil Kum Meh Orélien Sylvain Mtopi Bopda +7 位作者 Jerson Mekoulou Ndongo Franklin Chu Buh Claude Elysée Bika Léle Clarisse Noël Ayina Ayina Peguy Brice Assomo Ndemba Emmanuel Haddison Sako Bienvenu Bongue Samuel Honoré Mandengue 《Open Journal of Preventive Medicine》 CAS 2023年第5期109-128,共20页
Introduction: Work-related musculoskeletal disorders (WRMSDs) are a public health problem and have forced many workers to quit their jobs prematurely. This study investigated the prevalence and risk factors of WRMSDs ... Introduction: Work-related musculoskeletal disorders (WRMSDs) are a public health problem and have forced many workers to quit their jobs prematurely. This study investigated the prevalence and risk factors of WRMSDs among Healthcare workers in five reference hospitals in the City of Douala-Cameroon. Methods: A cross-sectional study was conducted in 2022 among 561 healthcare workers working in five reference hospitals in the city of Douala, Cameroon. Participants were selected using a convenient sampling technique. Data were collected with structured questionnaires;data on the demographics and risk factors were collected using a well-designed questionnaire, while estimation of the prevalence of WRMSDs was done using the Modified Nordic questionnaire. Results: The overall prevalence rate of WRMSDs among healthcare workers in Douala hospitals was 83.4% (468/561). The prevalence per professional groups was as follows: 88.8% (71) for Medical Laboratory Scientists (MLS), 81.9% (289) for nurses, 21 (80.8%) for Physiotherapists (PTs) and 78.8% (41) for Medical Doctors (MDs). There was a significant difference (p = 0.001) in the prevalence of WRMSDs with respect to place of work where healthcare workers from HLD recorded the highest prevalence 89.9%, while Healthcare workers from NBDH were 2.91 times at risk (AOR = 2.91;95% CI: 1.32 - 6.41;p = 0.001) to develop WRMSDs than healthcare workers in the other hospitals. With respect to body region, the highest prevalence of WRMSDs was recorded on the lower back, 58.8% with the lowest at the elbows 11.2%. The age group 30 to 39 years was significantly associated with WRMSDs at level of the shoulder (p = 0.002), upper back (p = 0.019), elbows (p Conclusion: The overall prevalence rate of WRMSDs among healthcare workers in Douala hospitals was high. The prevalence of WRMSDs is highest among MLS and nurses and the most affected body parts are;lower back, neck and upper back. Working on the same posture, stressful job, and repetitive tasks were the major risk factors associated to WRMSDs among healthcare workers in Douala hospitals. 展开更多
关键词 work-Related Musculoskeletal Disorders Risk Factors PREVALENCE Healthcare Workers Douala-Cameroon
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Exploring Work-Related Stress and Coping Strategies among Omani Nurses Working in Tertiary Governmental Hospitals at Muscat: A Cross-Sectional Study
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作者 Safiya Al-Yaqoubi 《Open Journal of Nursing》 2023年第6期368-385,共18页
Introduction: Work-related stress has become a global issue in the nursing workplace, with about 9.20% - 68.0% of nurses globally experiencing stress. Conversely, work-related stress ranges between 20% and 40% in nurs... Introduction: Work-related stress has become a global issue in the nursing workplace, with about 9.20% - 68.0% of nurses globally experiencing stress. Conversely, work-related stress ranges between 20% and 40% in nursing. Other researchers noted that 35.1% of nurses globally experienced elevated stress levels. Stress can damage well-being and lead to coping, which can, directly and indirectly, improve well-being through a perceived state. Nurses need coping mechanisms to manage their stress levels and maintain stability. Coping mechanisms can vary greatly depending on a nurse’s culture and background. Numerous findings indicate that managing stress is more critical than the cause of stress and that the more successful a stress-management approach, the less damage stress brings. Objective: In response to this, it is necessary to explore Omani nurses’ stress level and their coping strategies working in tertiary governmental hospitals in Muscat. Methods: The sample size for this study was 383 Omani nurses, with a 100% response rate. This study used a descriptive cross-sectional design from 15 October 2020 to 30 November 2020. Samples were selected through proportionate population sampling (PPS) from the five selected tertiary hospitals. Data were collected by self-administered questionnaires using a perceived stress scale and Ways of Coping. A simple random sample within a stratum (each hospital admitting ward) was done to identify the study participants. The sample size for this study was 383 Omani nurses, with a 100% response rate. Results: About 83.3% of participants had a moderate perceived level of stress with an overall mean perceived stress level of 18.46 ± 4.52. The most common sources of perceived stress are feeling nervous and “stressed” in the last month (2.30 ± 0.95). According to the ways of coping strategies, nurses seemed to be resorting to more “planful problem” (mean = 11.04) and least was seeking social support (mean = 9.67). Conclusion: This study highlighted the work-related stress level of staff nurses, explored their ways of coping and determined the relationship between work-related stress levels and methods of coping. The key finding of this study was that the frequency of stress reported by nurses was high enough to suggest that their stress levels were significant, given the demanding nature of their profession that requires maximum attention. Additionally, nurses seemed to resort to more planful problem-solving mechanisms to deal with their stressful situations than other coping strategies. 展开更多
关键词 Stress Level work-Related Stress Coping Strategies
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并行分治计算中的一种Work-stealing策略 被引量:2
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作者 杨际祥 谭国真 +1 位作者 王荣生 江德 《小型微型计算机系统》 CSCD 北大核心 2010年第3期408-412,共5页
在机群尤其是共享式多用户机群环境中提高非规则问题的并行计算效率是一项具有挑战性的工作.给出了一种适于多核处理器节点构成的机群的层次Work-stealing负载均衡策略(简称HWS),它能够有效利用节点的动态变化的可用计算资源.分析了分... 在机群尤其是共享式多用户机群环境中提高非规则问题的并行计算效率是一项具有挑战性的工作.给出了一种适于多核处理器节点构成的机群的层次Work-stealing负载均衡策略(简称HWS),它能够有效利用节点的动态变化的可用计算资源.分析了分治计算问题中的动态性与非规则性,并使用HWS策略对分治计算问题进行了动态负载均衡(DLB)实验.实验表明,HWS在加速比、CPU利用率和负载分布等性能指标上均优于Work-sharing和Satin-CRS策略. 展开更多
关键词 动态负载均衡(DLB) 层次work-stealing策略(HWS) 多核 分治法(D&C)
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Implementation of Resilience Engineering for Thoracic Surgery. Reconciling Work-as-Imagined and Work-as-Done
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作者 Takanori Ayabe Masaki Tomita +3 位作者 Ryo Maeda Manabu Okumura Kunihide Nakamura Kazue Nakajima 《Surgical Science》 2020年第9期257-273,共17页
<strong>Background:</strong> The Work-As-Imagined (WAI) is a plan that is expected to be performed before surgery, and the Work-As-Done (WAD) is the result of work actually done. In order to perform safe a... <strong>Background:</strong> The Work-As-Imagined (WAI) is a plan that is expected to be performed before surgery, and the Work-As-Done (WAD) is the result of work actually done. In order to perform safe and high-quality surgery for the individual surgeon, the surgical team, and hospital organization as a system, we have to reconcile the WAI and the WAD in resilience engineering for the real world of surgical healthcare. <strong>Objective:</strong> Based on the resilient healthcare theory, we would like to clarify the actual way of reconciling the WAI and WAD in surgery. <strong>Material and Methods:</strong> As a typical model of thoracic surgery, we use a lobectomy case for lung cancer. We describe a surgeon’s WAI and WAD, and we explain the anticipating, monitoring, responding, and learning based on the resilient healthcare theory. We reveal the gaps between the WAI and WAD during an operation, we consider the surgeon’s thinking and actual performance, and we describe the actual way of reconciling the WAI and WAD for the surgeon and surgical team. <strong>Outcomes:</strong> We described three scenes in the operating room, which are 1) by individual surgeon: adjustment for intrathoracic adhesion;2) by surgical team: adjustment for pulmonary artery bleeding;and 3) by surgical team with multi-professionals in the operating room: adjustment for life threatening pulmonary artery critical bleeding. <strong>Conclusion:</strong> In order to implement a resilient healthcare theory in everyday surgical work, it is important that 1) learning of incidents and the experience of doing well for unexpected events as lessons, and 2) constructing a circulation mechanism of anticipating, monitoring, responding, and learning. 展开更多
关键词 work-as-Imagined (WAI) work-as-Done (WAD) Surgery Resilience Engineering
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CICQ结构中逼近work-conserving的分组调度算法 被引量:1
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作者 张元昊 熊庆旭 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2016年第11期2481-2487,共7页
联合输入交叉点排队(CICQ)结构的分组调度算法是一个得到了充分研究的领域,但已有算法在吞吐率和分组平均时延方面与输出排队(OQ)的结果相比,依然不够令人满意,其关键在于OQ交换机可以工作于work-conserving状态。不同于已有的研究,本... 联合输入交叉点排队(CICQ)结构的分组调度算法是一个得到了充分研究的领域,但已有算法在吞吐率和分组平均时延方面与输出排队(OQ)的结果相比,依然不够令人满意,其关键在于OQ交换机可以工作于work-conserving状态。不同于已有的研究,本文提出了以使得交换机最大程度工作于work-conserving状态为目标的新的研究思路,给出并证明了CICQ交换机实现work-conserving状态的充分且必要条件。以此为基础,提出了一种新的CICQ输入调度的算法即交叉缓存队列均衡(CQB)算法,并将经典的最大队长优先(LQF)算法用于输出调度,结合得到CQB-LQF算法。仿真结果显示,与经典的及最新的CICQ分组调度算法相比,CQB-LQF算法显著提高了吞吐率及分组平均时延性能。 展开更多
关键词 分组交换 联合输入交叉点排队(CICQ) work-conserving 调度算法 时延 性能
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CONSTANT WORK-POINT CONTROL FOR PARALLEL HYBRID SYSTEM WITH CAPACITOR ACCUMULATOR IN HYDRAULIC EXCAVATOR 被引量:4
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作者 ZHANG Yanting WANG Qingfeng XIAO Qing FU Qiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第4期505-508,共4页
Limitations of various accumulators in hybrid hydraulic excavator are analyzed. A program using capacitor as the accumulator based on constant work-point control is put forward. A simulating experimental system of hyb... Limitations of various accumulators in hybrid hydraulic excavator are analyzed. A program using capacitor as the accumulator based on constant work-point control is put forward. A simulating experimental system of hybrid construction machinery is established, and experimental study on constant work-point control for parallel hybrid system with capacitor accumulator is carried out using the pressure and flow rate derived from boom cylinder of hydraulic excavator in actual work as the simulating loads. A program of double work-point control is proposed and proved by further experiments. 展开更多
关键词 Hybrid Hydraulic excavator Capacitor accumulator Constant work-point control Double work-point control
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Investigation on the plastic work-heat conversion coefficient of 7075-T651 aluminum alloy during an impact process based on infrared temperature measurement technology 被引量:3
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作者 Tong Zhang Ze-Rong Guo +1 位作者 Fu-Ping Yuan Hu-Sheng Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2018年第2期327-333,共7页
The plastic work-heat conversion coefficient is one key parameter for studying the work-heat conversion under dynamic deformation of materials. To explore this coefficient of 7075-T651 aluminum alloy under dynamic com... The plastic work-heat conversion coefficient is one key parameter for studying the work-heat conversion under dynamic deformation of materials. To explore this coefficient of 7075-T651 aluminum alloy under dynamic compression, dynamic compression experiments using the Hopkinson bar under four groups of strain rates were conducted, and the temperature signals were measured by constructing a transient infrared temperature measurement system. According to stress versus strain data as well as the corresponding temperature data obtained through the experiments, the influences of the strain and the strain rate on the coefficient of plastic work converted to heat were analyzed.The experimental results show that the coefficient of plastic work converted to heat of 7075-T651 aluminum alloy is not a constant at the range of 0.85–1 and is closely related to the strain and the strain rate. The change of internal structure of material under high strain rate reduces its energy storage capacity, and makes almost all plastic work convert into heat. 展开更多
关键词 Plastic work-heat conversion coefficient Infrared temperature measurement Dynamic compression 7075-T651 Aluminum alloy
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INSTANTANEOUS THERMAL EXPANSION BEHAVIOR OF HETEROGENEOUS MATERIALS WITH A WORK-HARDENING ELASTOPLASTIC MATRIX AND ELASTIC SPHEROIDAL INHOMOGENEITIES 被引量:1
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作者 ZHANG, QJ NAN, CW YUAN, RZ 《Acta Mechanica Solida Sinica》 SCIE EI 1995年第3期202-219,共18页
The instantaneous thermal expansion behavior of-two-phase heterogeneous materials subjected to a uniform temperature change is explored in the present study. The matrix phase is assumed to be a work-hardening ductile ... The instantaneous thermal expansion behavior of-two-phase heterogeneous materials subjected to a uniform temperature change is explored in the present study. The matrix phase is assumed to be a work-hardening ductile metal and the dispersive phase is assumed to consist of either aligned or randomly-oriented, elastic,, spheroidal inhomogeneities. The plastic flow and decreasing stiffness of the matrix during Eshelby's transformation strain of the equivalent inclusions are accounted for by using the deformation theory of plasticity. The explicit results of the instantaneous overall thermal expansion coefficients and the critical inelastic temperature changes are presented for aligned disc- and fiber-inclusions. For the spherical and randomly-oriented spheroidal inclusion, the present study demonstrates that when the yielding of the composites is governed by the average matrix stress, the overall response is always elastic in spite of the temperature change. 展开更多
关键词 work-HARDENING PLASTIC FLOW AVERAGE MATRIX STRESS
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The Role of Chest Computed Tomography in the Work-up of Patients with Cervical or Endometrial Cancer 被引量:1
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作者 Serap Demir Johanna M. A. Pijnenborg Ruud L. M. Bekkers 《Journal of Cancer Therapy》 2011年第4期441-447,共7页
Background and Objectives: To determine whether chest CT-scan in patients with cervical or endometrial cancer is of additional value for planning initial treatment and work-up. Methods: A retrospective analysis was pe... Background and Objectives: To determine whether chest CT-scan in patients with cervical or endometrial cancer is of additional value for planning initial treatment and work-up. Methods: A retrospective analysis was performed of 465 patients diagnosed with cervical or endometrial cancer between January 2003 and December 2007. All patients who underwent a chest CT-scan before treatment were included for analysis. Results: Out of 465 patients 74 patients underwent a pre-treatment chest CT-scan (cervical cancer, n = 58, and endometrial cancer, n = 26). Abnormalities were detected in 53.4% (31/58) and 73.1% (19/26) of patients with cervical and endometrial cancer, respectively. The majority of abnormalities were presumed to be benign, yet work-up was adjusted in 28.6% (13/58 and 11/26), and therapy was adjusted in 17.6% (6/58, and 7/26) of patients with cervical and endometrial cancer. Pulmonary metastasis were observed in 10.3% (6/58) and 24.1% (7/26) of patients with cervical cancer, and endometrial cancer, respectively. Most patients with pulmonary metastasis presented with extended disease based on clinical examination. Conclusions: Chest CT scans in patients with cervical and endometrial cancer frequently demonstrate abnormalities that are most likely benign, yet work-up is adjusted in a substantial number of cases. Therefore, chest CT-scan is only recommended for those patients with a clinical suspicion of extended disease. 展开更多
关键词 CHEST CT-SCAN ENDOMETRIAL CANCER CERVICAL CANCER work-up
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What Is the Role of Work-Related Factors in Self-Reported Health Inequalities among Employed Individuals? A Longitudinal Study in Luxembourg
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作者 Anastase Tchicaya Nathalie Lorentz Kristell Leduc 《Health》 2018年第9期1141-1158,共18页
Objectives: We measured health inequalities among employed Luxembourg residents over time and the socio-economic and work-related determinants. Design and Setting: Longitudinal data were obtained from the Socio-econom... Objectives: We measured health inequalities among employed Luxembourg residents over time and the socio-economic and work-related determinants. Design and Setting: Longitudinal data were obtained from the Socio-economic Liewen zu L&#235;tzebuerg/European Union Survey on Income and Living Conditions, which has been conducted each year since 2003 in Luxembourg. Participants: Participants comprised 727 Luxembourg residents (58% men), aged between 21 and 55 years in 2003, who were employed between 2003 and 2012. Primary and Secondary Outcomes Measured: The variable of interest was self-reported health. We used transition indicators on work-related factors to consider changes that individuals may have experienced in their job over this period. Results: People who moved from a part-time to a full-time contract (odds ratio (OR): 5.52, confidence interval (CI): 1.55 - 19.73), and those who moved from the 3rd or 4th quartile of earnings to the 1st or 2nd quartile (OR: 2.48, CI: 1.02 - 6.05) between 2003 and 2012, had a higher risk of being in poor health in 2012. The risk of deterioration in self-reported health in 2012 among people who were healthy in 2003 was associated with the type of contract, economic activity, and occupation. Conclusion: Health inequalities occur among employed people in Luxembourg. Their importance varies according to work-related characteristics and economic activity. Our findings showed that declined health status was associated with contract type, profession, and economic activity. This suggests that measures should be taken to maintain good health for people working in these specific occupations or economic sectors (e.g. preventive action, reduction of risk exposure, change of occupation in the same company, and so on). 展开更多
关键词 Employment HEALTH Inequalities Working Conditions EU-SILC work-RELATED Factors SELF-REPORTED HEALTH
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X-RAY ANALYSIS OF WORK-HARDENING PROCESS FOR POLYCRYSTALLINE α-BRASS DURING UNIAXIAL TENSILE TESTS
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作者 TENG Feng’en WANG Yuming Institute of Materials Science,Jilin University,Changchun,China Associate Professor,Institute of Materials Science,Jilin University,Changchun 130021,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1989年第5期387-389,共3页
X-ray diffraction Fourier profile analysis has been performed for polycrystalline α-brass plate with 31.55 wt-% Zn after a series of uniaxial tensile tests with different strain rates. Dislocation density p and confi... X-ray diffraction Fourier profile analysis has been performed for polycrystalline α-brass plate with 31.55 wt-% Zn after a series of uniaxial tensile tests with different strain rates. Dislocation density p and configuration parameter M may be presented as a function of ap- plied stress σ_a.A mechanism of alternative long-range and short-range strain hardening has been proposed. 展开更多
关键词 α-brass work-HARDENING X-ray diffraction
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Role of Rehabilitation Counseling and Psychology in Working with Individuals with Work-related Chronic Pain Injuries: An Interdisciplinary Approach-Chronic Pain and Work Injuries in the United States
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作者 Gloria K. Lee 《中国康复理论与实践》 CSCD 2006年第9期753-757,共5页
This paper addresses the topic of an interdisciplinary approach of chronic pain management from a biopsychosocial perspective. The first section provides an introduction to the definitions and theories of chronic pain... This paper addresses the topic of an interdisciplinary approach of chronic pain management from a biopsychosocial perspective. The first section provides an introduction to the definitions and theories of chronic pain and the various contributing factors (psychological, interpersonal/environmental and social support, and vocational). The second section presents the role of various health care professions (medical doctors, nurses, physical therapists, occupational therapists, psychologists and rehabilitation counselors) and the evidence of their treatment effectiveness. The third section discusses the concept of an interdisciplinary pain rehabilitation program (IPRP) and its evidence to support its effectiveness. Finally, the clinical implications of rehabilitation counseling and psychology as part of the inter-disciplinary program in treating individuals with chronic pain will be highlighted. 展开更多
关键词 chronic pain work-RELATED REHABILITATION PSYCHOLOGY COUNSELING interdisciplinary approach
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Research on Nanometer Technique and Low-Work-Loss Sensor
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作者 Lan Wang Yayan Liu +1 位作者 Yifei Yang Jingwen He1 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期110-112,共3页
The preparation process of the CO gas sensor used at normal temperature is presented.The electric conductance of this type of sensor evolved oscillation from regularly when the sensor is exposed to low level CO gas.Th... The preparation process of the CO gas sensor used at normal temperature is presented.The electric conductance of this type of sensor evolved oscillation from regularly when the sensor is exposed to low level CO gas.The gas sensing mechanism was investigated by its crystalline structure.The mechanism of information sensing,which was the concurrence of the grain boundary barrier control and the crystal surface control,is discussed. 展开更多
关键词 nanometer technique low-work-loss sensor
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The dynamical complexity of work-hardening:a large-scale molecular dynamics simulation
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作者 MarkusJ.Buehler AlexanderHartmaier +2 位作者 MarkA.Duchaineau FaridEAbraham HuajianGao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第2期103-111,共9页
We analyze a large-scale molecular dynamics simulation of work hardening in a model system of a ductile solid. With tensile loading, we observe emission of thousands of dislocations from two sharp cracks. The dislocat... We analyze a large-scale molecular dynamics simulation of work hardening in a model system of a ductile solid. With tensile loading, we observe emission of thousands of dislocations from two sharp cracks. The dislocations interact in a complex way, revealing three fundamental mechanisms of work-hardening in this ductile material. These are (1) dislocation cutting processes, jog formation and generation of trails of point defects; (2) activation of secondary slip systems by Frank-Read and cross-slip mechanisms; and (3) formation of sessile dislocations such as Lomer-Cottrell locks. We report the discovery of a new class of point defects referred to as trail of partial point defects, which could play an important role in situations when partial dislocations dominate plasticity. Another important result of the present work is the rediscovery of the Fleischer-mechanism of cross-slip of partial dislocations that was theoretically proposed more than 50 years ago, and is now, for the first time, confirmed by atomistic simulation. On the typical time scale of molecular dynamics simulations, the dislocations self-organize into a complex sessile defect topology. Our analysis illustrates numerous mechanisms formerly only conjectured in textbooks and observed indirectly in experiments. It is the first time that such a rich set of fundamental phenomena have been revealed in a single computer simulation, and its dynamical evolution has been studied. The present study exemplifies the simulation and analysis of the complex nonlinear dynamics of a many-particle system during failure using ultra-large scale computing. 展开更多
关键词 work-HARDENING Large-scale atomistic simulation Dislocation junction CROSS-SLIP
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Mechanism of Work-hardening for Austenitic Manganese Steel under Non-severe Impact Loading Conditions
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作者 谢敬佩 姜启川 +2 位作者 何镇明 hun(罗全顺) K.Sommer 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1992年第6期406-410,共5页
The effect of C,Mn and heat-treatment on work-hardening of austenitic Mn steel and the work-hardening mechanism have been investigated under non-severe impact loading condition.The results show that the ability of wor... The effect of C,Mn and heat-treatment on work-hardening of austenitic Mn steel and the work-hardening mechanism have been investigated under non-severe impact loading condition.The results show that the ability of work-hardening in- creases with the increase of C and aging tempera- ture but decreases with Mn.The work-hardening with high austenitic stability results mainly from dislocations,and that with low austenitic stability results mainly from combined effects of strain-in- duced martensite and high density of dislocations under non-severe impact loading conditions.The wear resistance of medium manganese steel (Mn7) is 1.64-2.46 times that of Hadfield steel (Mnl3). 展开更多
关键词 austenitic manganese steel mechanism of work-hardening
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Implementation of a Return to Work Strategy in Germany—Are There Changes in Work-Related Rehabilitation Measures and Employment Status in Chronic Conditions?
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作者 Cornelia Gerdau-Heitmann Monika Schwarze 《Open Journal of Therapy and Rehabilitation》 2016年第1期55-66,共12页
Objectives: Aging workforces with increasing numbers of chronic conditions require health initiatives with greater workplace focus. A regional pension insurance introduced a Return To Work (RTW) strategy for insurants... Objectives: Aging workforces with increasing numbers of chronic conditions require health initiatives with greater workplace focus. A regional pension insurance introduced a Return To Work (RTW) strategy for insurants with chronic conditions. The objective was to identify the degree of implementation of work related measures in medical rehabilitation and the extent of RTW outcomes. Methods: 5883 insurants were considered. Severe Restriction of Work Ability (SRWA), Work-related Medical Rehabilitation (WMR), and Case Management (CM) were examined for 2008 and 2012. An Index of Employment status (IoE) was used in a logistic regression. Results: Utilization of WMR raised from 12.3% in 2008 to 66.1% in 2012. The proportion of insurants with SRWA and WMR grew from 8% up to 40.1%. In 2008, 14.7% of insurants with SRWA received WMR;in 2012, it grew to 76.6%. On the other hand, in 2012 26% got WMR without SRWA and 12.2% had SRWA and got no WMR. CM was not conducted in 2008 but reached 20.2% in 2012. Across all indications, WMR resulted in positive RTW as measured by IoE: OR = 0.75 (KI-95%: 0.67 - 0.86). Conclusion: WMR was successfully implemented according to the German guideline. There is a need to optimize the linkage between SRWA and WMR and CM to provide need-based care. 展开更多
关键词 Chronic Conditions Return to Work (RTW) work-Related Medical Rehabilitation (WMR) Case Management (CM) Severe Restrictions of Work Ability (SRWA)
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Burnout and work-family conflict among nurses during the preparation for reevaluation of a grade A tertiary hospital
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作者 Ya-Xuan Fang 《Chinese Nursing Research》 CAS 2017年第1期51-55,共5页
Objectives: To gain a better understanding of nurse burnout and work-family conflict for nurses and to help the hospital prepare for hospital grade reevaluation.Methods: This study is a cross-sectional study, and 95... Objectives: To gain a better understanding of nurse burnout and work-family conflict for nurses and to help the hospital prepare for hospital grade reevaluation.Methods: This study is a cross-sectional study, and 95 nurses participated. The questionnaires included MBI and Carlson work-family conflict questionnaires, and the data were analyzed using SPSS 17.Results: A total of 71.6% of nurses worked over 8 h per day during the last two months before the reevaluation. The total score of burnout of nurses was 66.84 ± 12.60, and the proportion of heavy work burnout was 44.2%. The personal accomplishment takes the heaviest portion(80.0%). The total score of work-family conflict is 55.19 ± 9.27. The scores of work-to-family conflict are all higher than that of family-to-work conflict. The time dimension had the highest score.Conclusions: During the preparation period, nurses suffered from a heavy workload and intense job burnout, and many aspects of work-family conflict existed. 展开更多
关键词 Hospital grade reevaluation Nurse Burnout work-family conflict
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Humanoid Based Intelligence Control Strategy of Plastic Cement Die Press Work-Piece Forming Process for Polymer Plastics
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作者 Dekuan Liu Shuang Jin Hu Xu 《Journal of Materials Science and Chemical Engineering》 2016年第6期9-16,共8页
The plastic cement belongs to a sort of polymer material, the chemical composition is very complex, and the plastic cement work-piece is generally manufactured by die press forming. Aimed at being difficult to control... The plastic cement belongs to a sort of polymer material, the chemical composition is very complex, and the plastic cement work-piece is generally manufactured by die press forming. Aimed at being difficult to control in parameters of forming process, the paper explored the humanoid based intelligence control strategy. In the paper, it made the anatomy in control puzzle resulted in uncertainty such as chemical component of plastic cement etc., summarized up the characteristic of cybernetics in forming process, researched on the humanoid based intelligence control strategy, and constructed the control algorithm of forming process in plastic cement work-piece. Taking the process experiment of temperature and pressure control as an example, it validated the good dynamic and static control quality through simulation of control algorithm constructed in this paper. The experimental results show that the control algorithm explored in this paper is reasonably available. 展开更多
关键词 Plastic Cement Polymer Plastics Die Press work-Piece Forming Process Humanoid Based Intelligence Control
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