OBJECTIVES To evaluate the effectiveness of a large-scale,web-based,in-service hypertension management training project among lay health workers(LHWs) at primary care health(PHC) settings in China,and to examine the f...OBJECTIVES To evaluate the effectiveness of a large-scale,web-based,in-service hypertension management training project among lay health workers(LHWs) at primary care health(PHC) settings in China,and to examine the factors contributing to the variations of effectiveness.METHODS We used data from a web-based national hypertension management training project implemented in 2018,it was designed to facilitate LHWs to learn,understand,and apply the relevant knowledge and skills in hypertension management through providing training courses by use of the web-based platform with unified standards.All LHWs were required to participate in the exams before and after training to acquire scores for the use of evaluating their performance of hypertension management knowledge.We first used descriptive analysis to present the variations of effectiveness in hypertension management knowledge among LHWs by important subgroups.Afterwards,we used multilevel logistic regression to examine the individual and regional factors contributing to the variations and quantify the magnitude of how these factors affected training effectiveness.RESULTS There were 1,208,610 LHWs who completed training and were certificated.Nationally,the scores of LHWs increased significantly from 62.87 ± 21.14 out of 100 in the pre-test to 88.30 ± 11.31 in the post-test by 25.43(95% confidence interval[CI]:25.40-25.47).Training contents involved in antihypertensive medication showed the lowest score(54.36) in the pre-test and soared the most after training,up to 84.22 by 54.94%.Individual factors associated with disparities in the knowledge of hypertension management decreased substantially after training,which included sex,age,education,practice type,professional level,and hierarchy of working institutions.Geographical variations were shown at the provincial level,with the majority of them being explained by factors at the regional level.CONCLUSIONS Accessible web-based training modality,government efforts,accompanied with experiences derived from the training,could be generalized to other low-and middle-income countries in facilitating the hypertension management capacity of LHWs.Localization and evaluation is warranted on the way to its further application.展开更多
We are writing in response to the article titled“Addressing the needs and rights of sex workers for HIV healthcare services in the Philippines”[1].The article calls for attention on the significant challenges faced ...We are writing in response to the article titled“Addressing the needs and rights of sex workers for HIV healthcare services in the Philippines”[1].The article calls for attention on the significant challenges faced by sex workers in the Philippines in accessing HIV healthcare.We appreciate the article’s effort to examine these issues in depth.We would like to present a constant flow of thoughts in this letter while highlighting the positive aspects,potential obstacles,and additional points that contribute to this ongoing discussion.展开更多
Background Growing evidence attests to the efficacy of mindfulness-based interventions(MBIs),but their effectiveness for healthcare workers remains uncertain.Aims To evaluate the evidence for MBIs in improving healthc...Background Growing evidence attests to the efficacy of mindfulness-based interventions(MBIs),but their effectiveness for healthcare workers remains uncertain.Aims To evaluate the evidence for MBIs in improving healthcare workers’psychological well-being.Methods A systematic literature search was conducted on Medline,Embase,Cumulative Index for Nursing and Allied Health Literature,PsycINFO and Cochrane Central Register of Controlled Trials up to 31 August 2022 using the keywords‘healthcare worker’,‘doctor’,‘nurse’,‘allied health’,‘mindfulness’,‘wellness’,‘workshop’and‘program’.Randomised controlled trials with a defined MBI focusing on healthcare workers and quantitative outcome measures related to subjective or psychological well-being were eligible for inclusion.R V.4.0.3 was used for data analysis,with the standardised mean difference as the primary outcome,employing DerSimonian and Laird’s random effects model.Grading of Recommendations,Assessment,Development and Evaluation framework was used to evaluate the quality of evidence.Cochrane’s Risk of Bias 2 tool was used to assess the risk of bias in the included studies.Results A total of 27 studies with 2506 participants were included,mostly from the USA,involving various healthcare professions.MBIs such as stress reduction programmes,apps,meditation and training showed small to large effects on anxiety,burnout,stress,depression,psychological distress and job strain outcomes of the participants.Positive effects were also seen in self-compassion,empathy,mindfulness and well-being.However,long-term outcomes(1 month or longer postintervention)varied,and the effects were not consistently sustained.Conclusions MBIs offer short-term benefits in reducing stress-related symptoms in healthcare workers.The review also highlights limitations such as intervention heterogeneity,reduced power in specific subgroup analyses and variable study quality.展开更多
Purpose: Needle-stick injury (NSI) is one of the most potential occupational hazards for healthcare workers because of the transmission of blood-borne pathogens. As per recent data, around 30 lakh healthcare workers s...Purpose: Needle-stick injury (NSI) is one of the most potential occupational hazards for healthcare workers because of the transmission of blood-borne pathogens. As per recent data, around 30 lakh healthcare workers sustain Needle stick injuries each year. This study was conducted to assess healthcare workers’ knowledge, attitude and practices regarding needle stick injury. Materials & Methods: A cross-sectional study was conducted in a Tertiary Care Hospital over the period of 3 months. The study population consisted of Intern Doctors, Post Graduate resident Doctors, Staff Nurses, laboratory technicians of Government Medical College and New Civil Hospital, Surat (n = 300). The data were collected using a self-administered questionnaire via the means of Google Forms. Questionnaire was made with prior review literature. The data obtained were entered and analysed in Microsoft Excel. Results: The prevalence of NSI in our study was 46%, with a higher prevalence among the PG residents (72%). Overall scores regarding knowledge and attitude were better in PG residents (knowledge score > 7 in 71% and Attitude Score > 7 in 68% of PG Residents). Even though the PG residents scored highest in the knowledge category, the majority of them suffered needle stick injuries as a result of poor practice scores. Among those who had NSI (n = 139/300), 70% of study participants had superficial injuries, only 9% reported the incident, 18% got medical attention within 2 hours of the incident, and 7% followed up to recheck their viral markers status. Most incidents of NSI were due to hypodermic needles while recapping needles. Conclusion: Exposure to needle stick injuries and their underreporting remains a common problem. It is imperative that healthcare workers receive regular training on the proper handling of sharp objects. We can also draw the conclusion that preventing NSIs requires putting knowledge into practice.展开更多
Introduction: Violence is a major problem in today’s workplace. It affects workers in all sectors of activity. The aim of the study was to determine the prevalence and factors associated with violence among primary a...Introduction: Violence is a major problem in today’s workplace. It affects workers in all sectors of activity. The aim of the study was to determine the prevalence and factors associated with violence among primary and secondary school staff in Ouagadougou. Materials and Methods: This was a cross-sectional, descriptive and analytical study that took place from April 22, 2020 to February 18, 2021 in primary and secondary schools in Ouagadougou. It focused on the educational staff of these establishments. Results: A total of 362 agents took part in the study. The average age of participants was 36.5 ± 6.89 years. The sex ratio was 1.62 men to one woman. The majority of workers were teachers, with 300 participants (82.87%). The average job tenure was 7 years ± 6.91 years. With regard to violence in the workplace, 87 workers were victims, representing a prevalence of 24.03%. Of these workers, 59 (67.81%) were men and 36 (41.38%) had less than six years’ experience. Acts of violence were predominantly pushing observed in 15 workers (50%), while shouting and aggressive tone dominated psychological violence and concerned 54 cases (36.24%). On univariate analysis, the factors associated with violence were age (p = 0.046) and type of establishment (p = 0.012). On multivariate analysis, only the nature of the establishment was the only factor associated with the occurrence of violence among teaching staff (OR = 2.3690, p = 0.0213). Conclusion: The prevalence of violence is high in these educational establishments. Age and type of establishment are factors associated with its occurrence. It is therefore necessary to develop an effective strategy for preventing this risk in the workplace.展开更多
Identifying workers’construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress.However,current activity analysis methods for construction workers rely solely...Identifying workers’construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress.However,current activity analysis methods for construction workers rely solely on manual observations and recordings,which consumes considerable time and has high labor costs.Researchers have focused on monitoring on-site construction activities of workers.However,when multiple workers are working together,current research cannot accu rately and automatically identify the construction activity.This research proposes a deep learning framework for the automated analysis of the construction activities of multiple workers.In this framework,multiple deep neural network models are designed and used to complete worker key point extraction,worker tracking,and worker construction activity analysis.The designed framework was tested at an actual construction site,and activity recognition for multiple workers was performed,indicating the feasibility of the framework for the automated monitoring of work efficiency.展开更多
Piezoelectric stages use piezoelectric actuators and flexure hinges as driving and amplifying mechanisms,respectively.These systems have high positioning accuracy and high-frequency responses,and they are widely used ...Piezoelectric stages use piezoelectric actuators and flexure hinges as driving and amplifying mechanisms,respectively.These systems have high positioning accuracy and high-frequency responses,and they are widely used in various precision/ultra-precision positioning fields.However,the main challenge with these devices is the inherent hysteresis nonlinearity of piezoelectric actuators,which seriously affects the tracking accuracy of a piezoelectric stage.Inspired by this challenge,in this work,we developed a Hammerstein model to describe the hysteresis nonlinearity of a piezoelectric stage.In particular,in our proposed scheme,a feedback-linearization algorithm is used to eliminate the static hysteresis nonlinearity.In addition,a composite controller based on equivalent-disturbance compensation was designed to counteract model uncertainties and external disturbances.An analysis of the stability of a closed-loop system based on this feedback-linearization algorithm and composite controller was performed,and this was followed by extensive comparative experiments using a piezoelectric stage developed in the laboratory.The experimental results confirmed that the feedback-linearization algorithm and the composite controller offer improved linearization and trajectory-tracking performance.展开更多
Background: Bangladesh’s tea industry is essential to the country’s economic expansion. Since tea workers in Bangladesh are marginalized within our community, they have limited access to comprehensive eye care servi...Background: Bangladesh’s tea industry is essential to the country’s economic expansion. Since tea workers in Bangladesh are marginalized within our community, they have limited access to comprehensive eye care services. Productivity and well-being are cornerstones of comprehensive health care strategy. Ocular disorders are influenced by life expectancy, sociodemographic status, and the epidemiological transition. In this context, the state of ocular health and the many eye illnesses remain to be significantly addressed. Purpose: To evaluate the pattern of eye diseases among tea workers in a tea estate of Bangladesh. Methods: This cross-sectional observational study was carried out in Halda Valley Tea Estate, Nazirhat, Fatickchari, Chattogram, Bangladesh, under the supervision of the Department of Community Ophthalmology, BSMMU, following ethical clearance and approval by the IRB board of BSMMU. With informed written consent and approval from the authority of the tea estate, a total of 110 tea workers were recruited. Socio-demographic characteristics, ocular findings, and patterns of eye diseases were determined and recorded. Results: The mean age of the study participants was 39.60 ± 11.63 years. The maximum (58.1%) study participants were 31 - 50 years old, female (64.5%), illiterate (82.7%), and tribal (71.8%) indigenes. Eye diseases were found in 94.5% of workers. Presbyopia (28.2%), cataracts (27.3%), and refractive error (26.4%) were the most common. Tea workers with eye diseases were significantly older than those who did not have any eye diseases (40.20 ± 11.57 vs. 29.17 ± 7.31 years, p Conclusion: A significant number of tea workers had eye diseases, of which presbyopia, cataracts, and refractive error were the most common.展开更多
Background: Low back pain (LBP) is a very common health problem amongst the general population and a major cause of disability that affects work performance and well-being. Healthcare workers (HCWs) are especially at ...Background: Low back pain (LBP) is a very common health problem amongst the general population and a major cause of disability that affects work performance and well-being. Healthcare workers (HCWs) are especially at risk of developing LBP because of physical and emotional factors. Little is known about the burden of LBP in Cameroon. Objective: To determine the prevalence of low back pain and identify its associated factors among healthcare workers. Methods: A cross-sectional study using a self-administered questionnaire was conducted among healthcare workers in the Yaound Central Hospital and the Yaound University Teaching Hospital. The questionnaire collected data regarding recent, past year and lifetime occurrences of LBP, socio-demographics and work conditions. Data were analysed using IBM Statistical Package for Social Sciences (SPSS) version 26. Results: A total number of 268 HCWs participated in the study, including 197 (73.5%) females and 71 (26.5%) males. The mean age of the study participants was 40.60 8.38 years (extremes of 20 and 65 years). The lifetime, annual, and point prevalences of LBP among the participants were 67.5% (CI: 61.6 - 73.1), 61.5% (CI: 55.6 - 67.1) and 35.7% (CI: 29.7 - 41.5) respectively. Multivariate analysis confirmed a moderate stress level, a sedentary lifestyle, working in the medicine and specialities department, lifting heavy objects and bending to work as associated factors to LBP. Most sufferers had a minimal functional disability (65.7%) while 34.3% had a moderate to severe disability. Conclusions: Healthcare providers have a considerably high prevalence of low back pain. Factors associated with LBP found in this study were similar to those widely recognized in the literature. A substantial proportion of healthcare providers are suffering from functional disability associated with low back pain, affecting their social and work lives. There is a need for multilevel interventions to prevent and control low back pain in this highly vulnerable occupational group.展开更多
Background: Violence against women has become an international public health and human rights issue in recent decades. The violence suffered by sex workers is of little interest for research, yet it constitutes a majo...Background: Violence against women has become an international public health and human rights issue in recent decades. The violence suffered by sex workers is of little interest for research, yet it constitutes a major health and safety problem. We propose to assess the extent of the phenomenon of gender-based violence (GBV) among sex workers (SWs) in the city of Bangui in the CAR. Methodology: This is a descriptive cross-sectional epidemiological study covering the period from July to October 2021 carried out among SWs in Bangui, the capital of the CAR. Given that the SWs association had only 159 members in Bangui, an exhaustive sampling was retained. Were included in the study, any SW present during the data collection period and having given their written consent. The parameters studied were socio-demographic characteristics: age, sex, residence, level of education, marital status, and characteristics linked to violence: the notion of violence during their professional activity, the type of violence, the declaration and the declaration if necessary, the response and management of this violence. The data collected was analyzed using Epi info version 7 software. Results: Of the 159 SWs that counted the association, 108 had been included. The average age was 27.0 years with extremes of 14 and 46 years. The age groups of 25 to 34 years were the most represented (43.5%). Fifty-six SWs (51.9%) had reached the secondary level. Unemployed SWs were in the majority at 74.1%;Sixty-six (66) SWs in our sample (61.1%) had already been victims of violence during the exercise of their activity Sexual violence was the most represented (28.5%) followed by verbal violence (22.4%). Sixty-eight (62.9%) wanted to stop the professional activity of SWs and 93.1% would accept another income-generating activity in place of sex work. Conclusion: It is necessary to supervise SWs and protect them within the framework of respect for human rights, rather than criminalizing them and the exploiters flouting their human dignity and putting their lives in danger. .展开更多
A study was conducted to analyze the deformation mechanism of strongly weathered quartz schist in the Daliangshan Tunnel,located in the western Transverse Mountain area.A large deformation problem was experienced duri...A study was conducted to analyze the deformation mechanism of strongly weathered quartz schist in the Daliangshan Tunnel,located in the western Transverse Mountain area.A large deformation problem was experienced during the tunnel construction.To mitigate this problem,a support system was designed incorporating negative Poisson ratio(NPR)anchor cables with negative Poisson ratio effect.Physical model experiments,field experiments,and numerical simulation experiments were conducted to investigate the compensation mechanical behavior of NPR anchor cables.The large deformations of soft rocks in the Daliangshan Tunnel are caused by a high ground stress,a high degree of joint fracture development,and a high degree of surrounding rock fragmentation.A compensation mechanics support system combining long and short NPR anchor cables was suggested to provide sufficient counter-support force(approximately 350 kN)for the surrounding rock inside the tunnel.Comparing the NPR anchor cable support system with the original support system used in the Daliangshan tunnel showed that an NPR anchor cable support system,combining cables of 6.3 m and 10.3 m in length,effectively prevented convergence of surrounding rock deformation,and the integrated settlement convergence value remained below 300 mm.This study provides an effective scientific basis for resolving large deformation problems in deeply buried soft rocks in western transverse mountain areas.展开更多
This work investigates a multi-product parallel disassembly line balancing problem considering multi-skilled workers.A mathematical model for the parallel disassembly line is established to achieve maximized disassemb...This work investigates a multi-product parallel disassembly line balancing problem considering multi-skilled workers.A mathematical model for the parallel disassembly line is established to achieve maximized disassembly profit and minimized workstation cycle time.Based on a product’s AND/OR graph,matrices for task-skill,worker-skill,precedence relationships,and disassembly correlations are developed.A multi-objective discrete chemical reaction optimization algorithm is designed.To enhance solution diversity,improvements are made to four reactions:decomposition,synthesis,intermolecular ineffective collision,and wall invalid collision reaction,completing the evolution of molecular individuals.The established model and improved algorithm are applied to ball pen,flashlight,washing machine,and radio combinations,respectively.Introducing a Collaborative Resource Allocation(CRA)strategy based on a Decomposition-Based Multi-Objective Evolutionary Algorithm,the experimental results are compared with four classical algorithms:MOEA/D,MOEAD-CRA,Non-dominated Sorting Genetic Algorithm Ⅱ(NSGA-Ⅱ),and Non-dominated Sorting Genetic Algorithm Ⅲ(NSGA-Ⅲ).This validates the feasibility and superiority of the proposed algorithm in parallel disassembly production lines.展开更多
Objectives: Sex work is not well documented among African men. The aim of this study was to describe the epidemiological profile of men who have sex with men (MSM) and eventually to determine the proportion of sex wor...Objectives: Sex work is not well documented among African men. The aim of this study was to describe the epidemiological profile of men who have sex with men (MSM) and eventually to determine the proportion of sex workers (SW) among them, as well as the proportion of MSM who have been victims of gender-based violence (GBV). Material and Methods: A cross-sectional study coordinated by the Direction de la Médecine du Travail was carried out at the headquarters of the association ALTERNATIVES in Bangui Bangui from July 1 to October 31, 2021. Consenting MSM present during the study period were systematically included. Sociodemographic variables, those relating to the future vision of the activity and to GBV were collected and analyzed using Epi-Info version 7 software. Results: Forty MSM with an average age of 23 years and mainly secondary education (75.0%) were included. The vast majority of MSM were unemployed (85.0%). 45.0% had been victims of GBV and wanted to stop working as an MSM (47.5%), and almost 2/3 (65.0%) would accept another income-generating activity in exchange for the MSM. Violence was sexual (32.5%), economic (22.5%), physical (20.0%), verbal (12.5%) and psychological (12.5%). Conclusion: The MSM were mainly young, poorly educated, unemployed, and almost half were victims of GBV. The desire to change MSM activity to another income-generating activity alongside that of MSM shows that many of them are SW, workers in the informal sector. This must be taken into account in prevention activities, even if the data needs to be confirmed on a much larger sample.展开更多
Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle accelerator.It is important to obtain time-domain waveforms of these signals with high temporal re...Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle accelerator.It is important to obtain time-domain waveforms of these signals with high temporal resolution for research,such as the study of beam–cavity interactions and bunch-by-bunch parameter measurements.Therefore,a signal reconstruction algorithm with ultrahigh spatiotemporal resolution and bunch phase compensation based on equivalent sampling is proposed in this paper.Compared with traditional equivalent sampling,the use of phase compensation and setting the bunch signal zero-crossing point as the time reference can construct a more accurate reconstructed signal.The basic principles of the method,simulation,and experimental comparison are also introduced.Based on the beam test platform of the Shanghai Synchrotron Radiation Facility(SSRF)and the method of experimental verification,the factors that affect the reconstructed signal quality are analyzed and discussed,including the depth of the sampled data,quantization noise of analog-to-digital converter,beam transverse oscillation,and longitudinal oscillation.The results of the beam experiments show that under the user operation conditions of the SSRF,a beam excitation signal with an amplitude uncertainty of 2%can be reconstructed.展开更多
Mobile young white-collar workers not only have the characteristics of mobile young people,but also have the characteristics of general white-collar workers.Under the influence of both,their mental health may be suffe...Mobile young white-collar workers not only have the characteristics of mobile young people,but also have the characteristics of general white-collar workers.Under the influence of both,their mental health may be suffering from“double disadvantage”.So,based on an ecological model of the stress process,this paper tries to use the data of the questionnaire on the mental health of mobile young white-collar workers in Zhejiang Province to explore the influence of some factors in the middle workplace and residence place on the mental health of micro individuals.The results show that:(1)The working environment with high control and low freedom and the workplace discrimination against the mobile status will have a negative impact on the mental health of mobile young white-collar workers;(2)Financial anxiety in daily life will lead to a decline in the mental health level of mobile young white-collar workers;(3)Good organizational support and neighborhood social relations can significantly relieve life pressure,so as to effectively improve the mental health of mobile young white-collar workers.It can be seen that we also need to pay more attention to the mental health of mobile young white-collar workers in order to improve their situation.展开更多
To overcome large deformation of deep phosphate rock roadways and pillar damage,a new type of constant-resistance large-deformation negative Poisson’s ratio(NPR)bolt that can withstand a high prestress of at least 13...To overcome large deformation of deep phosphate rock roadways and pillar damage,a new type of constant-resistance large-deformation negative Poisson’s ratio(NPR)bolt that can withstand a high prestress of at least 130 KN was developed.In the conducted tests,the amount of deformation was 200-2000 mm,the breaking force reached 350 KN,and a high constant-resistance pre-stress was maintained during the deformation process.A stress compensation theory of phosphate rock excavation based on NPR bolts is proposed together with a balance system for bolt compensation of the time-space effect and high NPR pre-stress.Traditional split-set rock bolts are unable to maintain the stability of roadway roofs and pillars.To verify the support effect of the proposed bolt,field tests were conducted using both the proposed NPR bolts and split-set rock bolts as support systems on the same mining face.In addition,the stress compensation mechanism of roadway mining was simulated using the particle flow code in three dimensions(PFC^(3D))-fast Lagrangian analysis of continua(FLAC^(3D))particle-flow coupling numerical model.On-site monitoring and numerical simulations showed that the NPR excavation compensation support scheme effectively improves the stress state of the bolts and reduces the deformation of the surrounding rock.Compared to the original support scheme,the final deformation of the surrounding rock was reduced by approximately 70%.These results significantly contribute to domestic and foreign research on phosphate-rock NPR compensation support technology,theoretical systems,and engineering practices,and further promote technological innovation in the phosphate rock mining industry.展开更多
Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application ...Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application in the future,the thermal stability of this substance during storage,transportation,and use will become quite important.Thus,in this work,the thermal decomposition behavior,thermal decomposition kinetics,and thermal hazard of ADCA were investigated.Experiments were conducted by using a SENSYS evo DSC device.A combination of differential iso-conversion method,compensation parameter method,and nonlinear fitting evaluation were also used to analyze thermal kinetics and mechanism of ADCA decomposition.The results show that when conversion rate α increases,the activation energies of ADCA's first and main decomposition peaks fall.The amount of heat released during decomposition varies between 182.46 and 231.16 J·g^(-1).The proposed kinetic equation is based on the Avrami-Erofeev model,which is consistent with the decomposition progress.Applying the Frank-Kamenetskii model,a calculated self-accelerating decomposition temperature of 287.0℃is obtained.展开更多
In the fiber winding process,strong disturbance,uncertainty,strong coupling,and fiber friction complicate the winding constant tension control.In order to effectively reduce the influence of these problems on the tens...In the fiber winding process,strong disturbance,uncertainty,strong coupling,and fiber friction complicate the winding constant tension control.In order to effectively reduce the influence of these problems on the tension output,this paper proposed a tension fluctuation rejection strategy based on feedforward compensation.In addition to the bias harmonic curve of the unknown state,the tension fluctuation also contains the influence of bounded noise.A tension fluctuation observer(TFO)is designed to cancel the uncertain periodic signal,in which the frequency generator is used to estimate the critical parameter information.Then,the fluctuation signal is reconstructed by a third-order auxiliary filter.The estimated signal feedforward compensates for the actual tension fluctuation.Furthermore,a time-varying parameters fractional-order PID controller(TPFOPID)is realized to attenuate the bounded noise in the fluctuation.Finally,TPFOPID is enhanced by TFO and applied to control a tension control system considering multi-source disturbances.The stability of the method is analyzed by using the Lyapunov theorem.Finally,numerical simulations verify that the proposed scheme improves the tracking ability and robustness of the system in response to tension fluctuations.展开更多
BACKGROUND Violence against healthcare workers(HCWs)in the Caribbean continues to prevail yet remains underreported.Our aim is to determine the cause,traits,and consequences of violence on HCWs in the Caribbean.AIM To...BACKGROUND Violence against healthcare workers(HCWs)in the Caribbean continues to prevail yet remains underreported.Our aim is to determine the cause,traits,and consequences of violence on HCWs in the Caribbean.AIM To determine the cause,traits,and consequences of violence on HCWs in the Caribbean.METHODS This research adopted an online cross-sectional survey approach,spanning over eight weeks(between June 6th and August 9th,2022).The survey was generated using Research Electronic Data Capture forms and followed a snowballing strategy to contact individuals using emails,social media,text messages,etc.Logistic regression analysis was performed to evaluate the variables that influence violence,including gender,age,years of experience,institution type,and night shift frequency.RESULTS The survey was completed by 225 HCWs.Females comprised 61%.Over 51%of respondents belonged to the 21 to 35 age group.Dominica(n=61),Haiti(n=50),and Grenada(n=31)had the most responses.Most HCWs(49%)worked for government academic institutions,followed by community hospitals(23%).Medical students(32%),followed by attending physicians(22%),and others(16%)comprised the most common cadre of respondents.About 39%of the participants reported experiencing violence themselves,and 18%reported violence against colleague(s).Verbal violence(48%),emotional abuse(24%),and physical misconduct(14%)were the most common types of violence.Nearly 63%of respondents identified patients or their relatives as the most frequent aggressors.Univariate logistic regression analyses demonstrated that female gender(OR=2.08;95%CI:1.16-3.76,P=0.014)and higher frequency of night shifts(OR=2.22;95%CI:1.08-4.58,P=0.030)were associated with significantly higher odds of experiencing violence.More than 50%of HCWs felt less motivated and had decreased job satisfaction post-violent conduct.CONCLUSION A large proportion of HCWS in the Caribbean are exposed to violence,yet the phenomenon remains underreported.As a result,HCWs’job satisfaction has diminished.展开更多
Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ratio.However,most HDUs are throttling-valve-controlled cylinder systems,which exhi...Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ratio.However,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy losses.By contrast,pump control systems offer a high efficiency.Nevertheless,their response ability is unsatisfactory.To fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(PCDS)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of robots.Herein,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the PCDS force control system is first introduced.In addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC herein.This method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the system.Finally,experimental verification is performed using the PCDS performance test platform.The experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the PCDS.The relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot.展开更多
文摘OBJECTIVES To evaluate the effectiveness of a large-scale,web-based,in-service hypertension management training project among lay health workers(LHWs) at primary care health(PHC) settings in China,and to examine the factors contributing to the variations of effectiveness.METHODS We used data from a web-based national hypertension management training project implemented in 2018,it was designed to facilitate LHWs to learn,understand,and apply the relevant knowledge and skills in hypertension management through providing training courses by use of the web-based platform with unified standards.All LHWs were required to participate in the exams before and after training to acquire scores for the use of evaluating their performance of hypertension management knowledge.We first used descriptive analysis to present the variations of effectiveness in hypertension management knowledge among LHWs by important subgroups.Afterwards,we used multilevel logistic regression to examine the individual and regional factors contributing to the variations and quantify the magnitude of how these factors affected training effectiveness.RESULTS There were 1,208,610 LHWs who completed training and were certificated.Nationally,the scores of LHWs increased significantly from 62.87 ± 21.14 out of 100 in the pre-test to 88.30 ± 11.31 in the post-test by 25.43(95% confidence interval[CI]:25.40-25.47).Training contents involved in antihypertensive medication showed the lowest score(54.36) in the pre-test and soared the most after training,up to 84.22 by 54.94%.Individual factors associated with disparities in the knowledge of hypertension management decreased substantially after training,which included sex,age,education,practice type,professional level,and hierarchy of working institutions.Geographical variations were shown at the provincial level,with the majority of them being explained by factors at the regional level.CONCLUSIONS Accessible web-based training modality,government efforts,accompanied with experiences derived from the training,could be generalized to other low-and middle-income countries in facilitating the hypertension management capacity of LHWs.Localization and evaluation is warranted on the way to its further application.
文摘We are writing in response to the article titled“Addressing the needs and rights of sex workers for HIV healthcare services in the Philippines”[1].The article calls for attention on the significant challenges faced by sex workers in the Philippines in accessing HIV healthcare.We appreciate the article’s effort to examine these issues in depth.We would like to present a constant flow of thoughts in this letter while highlighting the positive aspects,potential obstacles,and additional points that contribute to this ongoing discussion.
文摘Background Growing evidence attests to the efficacy of mindfulness-based interventions(MBIs),but their effectiveness for healthcare workers remains uncertain.Aims To evaluate the evidence for MBIs in improving healthcare workers’psychological well-being.Methods A systematic literature search was conducted on Medline,Embase,Cumulative Index for Nursing and Allied Health Literature,PsycINFO and Cochrane Central Register of Controlled Trials up to 31 August 2022 using the keywords‘healthcare worker’,‘doctor’,‘nurse’,‘allied health’,‘mindfulness’,‘wellness’,‘workshop’and‘program’.Randomised controlled trials with a defined MBI focusing on healthcare workers and quantitative outcome measures related to subjective or psychological well-being were eligible for inclusion.R V.4.0.3 was used for data analysis,with the standardised mean difference as the primary outcome,employing DerSimonian and Laird’s random effects model.Grading of Recommendations,Assessment,Development and Evaluation framework was used to evaluate the quality of evidence.Cochrane’s Risk of Bias 2 tool was used to assess the risk of bias in the included studies.Results A total of 27 studies with 2506 participants were included,mostly from the USA,involving various healthcare professions.MBIs such as stress reduction programmes,apps,meditation and training showed small to large effects on anxiety,burnout,stress,depression,psychological distress and job strain outcomes of the participants.Positive effects were also seen in self-compassion,empathy,mindfulness and well-being.However,long-term outcomes(1 month or longer postintervention)varied,and the effects were not consistently sustained.Conclusions MBIs offer short-term benefits in reducing stress-related symptoms in healthcare workers.The review also highlights limitations such as intervention heterogeneity,reduced power in specific subgroup analyses and variable study quality.
文摘Purpose: Needle-stick injury (NSI) is one of the most potential occupational hazards for healthcare workers because of the transmission of blood-borne pathogens. As per recent data, around 30 lakh healthcare workers sustain Needle stick injuries each year. This study was conducted to assess healthcare workers’ knowledge, attitude and practices regarding needle stick injury. Materials & Methods: A cross-sectional study was conducted in a Tertiary Care Hospital over the period of 3 months. The study population consisted of Intern Doctors, Post Graduate resident Doctors, Staff Nurses, laboratory technicians of Government Medical College and New Civil Hospital, Surat (n = 300). The data were collected using a self-administered questionnaire via the means of Google Forms. Questionnaire was made with prior review literature. The data obtained were entered and analysed in Microsoft Excel. Results: The prevalence of NSI in our study was 46%, with a higher prevalence among the PG residents (72%). Overall scores regarding knowledge and attitude were better in PG residents (knowledge score > 7 in 71% and Attitude Score > 7 in 68% of PG Residents). Even though the PG residents scored highest in the knowledge category, the majority of them suffered needle stick injuries as a result of poor practice scores. Among those who had NSI (n = 139/300), 70% of study participants had superficial injuries, only 9% reported the incident, 18% got medical attention within 2 hours of the incident, and 7% followed up to recheck their viral markers status. Most incidents of NSI were due to hypodermic needles while recapping needles. Conclusion: Exposure to needle stick injuries and their underreporting remains a common problem. It is imperative that healthcare workers receive regular training on the proper handling of sharp objects. We can also draw the conclusion that preventing NSIs requires putting knowledge into practice.
文摘Introduction: Violence is a major problem in today’s workplace. It affects workers in all sectors of activity. The aim of the study was to determine the prevalence and factors associated with violence among primary and secondary school staff in Ouagadougou. Materials and Methods: This was a cross-sectional, descriptive and analytical study that took place from April 22, 2020 to February 18, 2021 in primary and secondary schools in Ouagadougou. It focused on the educational staff of these establishments. Results: A total of 362 agents took part in the study. The average age of participants was 36.5 ± 6.89 years. The sex ratio was 1.62 men to one woman. The majority of workers were teachers, with 300 participants (82.87%). The average job tenure was 7 years ± 6.91 years. With regard to violence in the workplace, 87 workers were victims, representing a prevalence of 24.03%. Of these workers, 59 (67.81%) were men and 36 (41.38%) had less than six years’ experience. Acts of violence were predominantly pushing observed in 15 workers (50%), while shouting and aggressive tone dominated psychological violence and concerned 54 cases (36.24%). On univariate analysis, the factors associated with violence were age (p = 0.046) and type of establishment (p = 0.012). On multivariate analysis, only the nature of the establishment was the only factor associated with the occurrence of violence among teaching staff (OR = 2.3690, p = 0.0213). Conclusion: The prevalence of violence is high in these educational establishments. Age and type of establishment are factors associated with its occurrence. It is therefore necessary to develop an effective strategy for preventing this risk in the workplace.
基金supported by the National Natural Science Foundation of China(52130801,U20A20312,52178271,and 52077213)the National Key Research and Development Program of China(2021YFF0500903)。
文摘Identifying workers’construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress.However,current activity analysis methods for construction workers rely solely on manual observations and recordings,which consumes considerable time and has high labor costs.Researchers have focused on monitoring on-site construction activities of workers.However,when multiple workers are working together,current research cannot accu rately and automatically identify the construction activity.This research proposes a deep learning framework for the automated analysis of the construction activities of multiple workers.In this framework,multiple deep neural network models are designed and used to complete worker key point extraction,worker tracking,and worker construction activity analysis.The designed framework was tested at an actual construction site,and activity recognition for multiple workers was performed,indicating the feasibility of the framework for the automated monitoring of work efficiency.
基金supported by the National Key R&D Program of China (Grant No.2022YFB3206700)the Independent Research Project of the State Key Laboratory of Mechanical Transmission (Grant No.SKLMT-ZZKT-2022M06)the Innovation Group Science Fund of Chongqing Natural Science Foundation (Grant No.cstc2019jcyj-cxttX0003).
文摘Piezoelectric stages use piezoelectric actuators and flexure hinges as driving and amplifying mechanisms,respectively.These systems have high positioning accuracy and high-frequency responses,and they are widely used in various precision/ultra-precision positioning fields.However,the main challenge with these devices is the inherent hysteresis nonlinearity of piezoelectric actuators,which seriously affects the tracking accuracy of a piezoelectric stage.Inspired by this challenge,in this work,we developed a Hammerstein model to describe the hysteresis nonlinearity of a piezoelectric stage.In particular,in our proposed scheme,a feedback-linearization algorithm is used to eliminate the static hysteresis nonlinearity.In addition,a composite controller based on equivalent-disturbance compensation was designed to counteract model uncertainties and external disturbances.An analysis of the stability of a closed-loop system based on this feedback-linearization algorithm and composite controller was performed,and this was followed by extensive comparative experiments using a piezoelectric stage developed in the laboratory.The experimental results confirmed that the feedback-linearization algorithm and the composite controller offer improved linearization and trajectory-tracking performance.
文摘Background: Bangladesh’s tea industry is essential to the country’s economic expansion. Since tea workers in Bangladesh are marginalized within our community, they have limited access to comprehensive eye care services. Productivity and well-being are cornerstones of comprehensive health care strategy. Ocular disorders are influenced by life expectancy, sociodemographic status, and the epidemiological transition. In this context, the state of ocular health and the many eye illnesses remain to be significantly addressed. Purpose: To evaluate the pattern of eye diseases among tea workers in a tea estate of Bangladesh. Methods: This cross-sectional observational study was carried out in Halda Valley Tea Estate, Nazirhat, Fatickchari, Chattogram, Bangladesh, under the supervision of the Department of Community Ophthalmology, BSMMU, following ethical clearance and approval by the IRB board of BSMMU. With informed written consent and approval from the authority of the tea estate, a total of 110 tea workers were recruited. Socio-demographic characteristics, ocular findings, and patterns of eye diseases were determined and recorded. Results: The mean age of the study participants was 39.60 ± 11.63 years. The maximum (58.1%) study participants were 31 - 50 years old, female (64.5%), illiterate (82.7%), and tribal (71.8%) indigenes. Eye diseases were found in 94.5% of workers. Presbyopia (28.2%), cataracts (27.3%), and refractive error (26.4%) were the most common. Tea workers with eye diseases were significantly older than those who did not have any eye diseases (40.20 ± 11.57 vs. 29.17 ± 7.31 years, p Conclusion: A significant number of tea workers had eye diseases, of which presbyopia, cataracts, and refractive error were the most common.
文摘Background: Low back pain (LBP) is a very common health problem amongst the general population and a major cause of disability that affects work performance and well-being. Healthcare workers (HCWs) are especially at risk of developing LBP because of physical and emotional factors. Little is known about the burden of LBP in Cameroon. Objective: To determine the prevalence of low back pain and identify its associated factors among healthcare workers. Methods: A cross-sectional study using a self-administered questionnaire was conducted among healthcare workers in the Yaound Central Hospital and the Yaound University Teaching Hospital. The questionnaire collected data regarding recent, past year and lifetime occurrences of LBP, socio-demographics and work conditions. Data were analysed using IBM Statistical Package for Social Sciences (SPSS) version 26. Results: A total number of 268 HCWs participated in the study, including 197 (73.5%) females and 71 (26.5%) males. The mean age of the study participants was 40.60 8.38 years (extremes of 20 and 65 years). The lifetime, annual, and point prevalences of LBP among the participants were 67.5% (CI: 61.6 - 73.1), 61.5% (CI: 55.6 - 67.1) and 35.7% (CI: 29.7 - 41.5) respectively. Multivariate analysis confirmed a moderate stress level, a sedentary lifestyle, working in the medicine and specialities department, lifting heavy objects and bending to work as associated factors to LBP. Most sufferers had a minimal functional disability (65.7%) while 34.3% had a moderate to severe disability. Conclusions: Healthcare providers have a considerably high prevalence of low back pain. Factors associated with LBP found in this study were similar to those widely recognized in the literature. A substantial proportion of healthcare providers are suffering from functional disability associated with low back pain, affecting their social and work lives. There is a need for multilevel interventions to prevent and control low back pain in this highly vulnerable occupational group.
文摘Background: Violence against women has become an international public health and human rights issue in recent decades. The violence suffered by sex workers is of little interest for research, yet it constitutes a major health and safety problem. We propose to assess the extent of the phenomenon of gender-based violence (GBV) among sex workers (SWs) in the city of Bangui in the CAR. Methodology: This is a descriptive cross-sectional epidemiological study covering the period from July to October 2021 carried out among SWs in Bangui, the capital of the CAR. Given that the SWs association had only 159 members in Bangui, an exhaustive sampling was retained. Were included in the study, any SW present during the data collection period and having given their written consent. The parameters studied were socio-demographic characteristics: age, sex, residence, level of education, marital status, and characteristics linked to violence: the notion of violence during their professional activity, the type of violence, the declaration and the declaration if necessary, the response and management of this violence. The data collected was analyzed using Epi info version 7 software. Results: Of the 159 SWs that counted the association, 108 had been included. The average age was 27.0 years with extremes of 14 and 46 years. The age groups of 25 to 34 years were the most represented (43.5%). Fifty-six SWs (51.9%) had reached the secondary level. Unemployed SWs were in the majority at 74.1%;Sixty-six (66) SWs in our sample (61.1%) had already been victims of violence during the exercise of their activity Sexual violence was the most represented (28.5%) followed by verbal violence (22.4%). Sixty-eight (62.9%) wanted to stop the professional activity of SWs and 93.1% would accept another income-generating activity in place of sex work. Conclusion: It is necessary to supervise SWs and protect them within the framework of respect for human rights, rather than criminalizing them and the exploiters flouting their human dignity and putting their lives in danger. .
基金Project(41941018)supported by the National Natural Science Foundation of China for the Special Project FundingProject(22-JKCF-08)supported by the Study on in-situ Stress Database and 3D in-situ Stress Inversion Technology of Highway Tunnel in Shanxi Province,China+1 种基金Project(2022-JKKJ-6)supported by the Study on Disaster Mechanism and NPR Anchor Cable Prevention and Control of Coal Mining Caving Subsidence in Operating Tunnel in Mountainous Area,ChinaProject(BBJ2024032)supported by the Fundamental Research Funds for the Central Universities(PhD Top Innovative Talents Fund of CUMTB),China。
文摘A study was conducted to analyze the deformation mechanism of strongly weathered quartz schist in the Daliangshan Tunnel,located in the western Transverse Mountain area.A large deformation problem was experienced during the tunnel construction.To mitigate this problem,a support system was designed incorporating negative Poisson ratio(NPR)anchor cables with negative Poisson ratio effect.Physical model experiments,field experiments,and numerical simulation experiments were conducted to investigate the compensation mechanical behavior of NPR anchor cables.The large deformations of soft rocks in the Daliangshan Tunnel are caused by a high ground stress,a high degree of joint fracture development,and a high degree of surrounding rock fragmentation.A compensation mechanics support system combining long and short NPR anchor cables was suggested to provide sufficient counter-support force(approximately 350 kN)for the surrounding rock inside the tunnel.Comparing the NPR anchor cable support system with the original support system used in the Daliangshan tunnel showed that an NPR anchor cable support system,combining cables of 6.3 m and 10.3 m in length,effectively prevented convergence of surrounding rock deformation,and the integrated settlement convergence value remained below 300 mm.This study provides an effective scientific basis for resolving large deformation problems in deeply buried soft rocks in western transverse mountain areas.
文摘This work investigates a multi-product parallel disassembly line balancing problem considering multi-skilled workers.A mathematical model for the parallel disassembly line is established to achieve maximized disassembly profit and minimized workstation cycle time.Based on a product’s AND/OR graph,matrices for task-skill,worker-skill,precedence relationships,and disassembly correlations are developed.A multi-objective discrete chemical reaction optimization algorithm is designed.To enhance solution diversity,improvements are made to four reactions:decomposition,synthesis,intermolecular ineffective collision,and wall invalid collision reaction,completing the evolution of molecular individuals.The established model and improved algorithm are applied to ball pen,flashlight,washing machine,and radio combinations,respectively.Introducing a Collaborative Resource Allocation(CRA)strategy based on a Decomposition-Based Multi-Objective Evolutionary Algorithm,the experimental results are compared with four classical algorithms:MOEA/D,MOEAD-CRA,Non-dominated Sorting Genetic Algorithm Ⅱ(NSGA-Ⅱ),and Non-dominated Sorting Genetic Algorithm Ⅲ(NSGA-Ⅲ).This validates the feasibility and superiority of the proposed algorithm in parallel disassembly production lines.
文摘Objectives: Sex work is not well documented among African men. The aim of this study was to describe the epidemiological profile of men who have sex with men (MSM) and eventually to determine the proportion of sex workers (SW) among them, as well as the proportion of MSM who have been victims of gender-based violence (GBV). Material and Methods: A cross-sectional study coordinated by the Direction de la Médecine du Travail was carried out at the headquarters of the association ALTERNATIVES in Bangui Bangui from July 1 to October 31, 2021. Consenting MSM present during the study period were systematically included. Sociodemographic variables, those relating to the future vision of the activity and to GBV were collected and analyzed using Epi-Info version 7 software. Results: Forty MSM with an average age of 23 years and mainly secondary education (75.0%) were included. The vast majority of MSM were unemployed (85.0%). 45.0% had been victims of GBV and wanted to stop working as an MSM (47.5%), and almost 2/3 (65.0%) would accept another income-generating activity in exchange for the MSM. Violence was sexual (32.5%), economic (22.5%), physical (20.0%), verbal (12.5%) and psychological (12.5%). Conclusion: The MSM were mainly young, poorly educated, unemployed, and almost half were victims of GBV. The desire to change MSM activity to another income-generating activity alongside that of MSM shows that many of them are SW, workers in the informal sector. This must be taken into account in prevention activities, even if the data needs to be confirmed on a much larger sample.
基金supported by the National Key R&D Program of China(No.2022YFA1602201)the international partnership program of the Chinese Academy of Sciences(No.211134KYSB20200057).
文摘Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle accelerator.It is important to obtain time-domain waveforms of these signals with high temporal resolution for research,such as the study of beam–cavity interactions and bunch-by-bunch parameter measurements.Therefore,a signal reconstruction algorithm with ultrahigh spatiotemporal resolution and bunch phase compensation based on equivalent sampling is proposed in this paper.Compared with traditional equivalent sampling,the use of phase compensation and setting the bunch signal zero-crossing point as the time reference can construct a more accurate reconstructed signal.The basic principles of the method,simulation,and experimental comparison are also introduced.Based on the beam test platform of the Shanghai Synchrotron Radiation Facility(SSRF)and the method of experimental verification,the factors that affect the reconstructed signal quality are analyzed and discussed,including the depth of the sampled data,quantization noise of analog-to-digital converter,beam transverse oscillation,and longitudinal oscillation.The results of the beam experiments show that under the user operation conditions of the SSRF,a beam excitation signal with an amplitude uncertainty of 2%can be reconstructed.
基金the National Social Science Fund of China(Grant No.20BTJ005).
文摘Mobile young white-collar workers not only have the characteristics of mobile young people,but also have the characteristics of general white-collar workers.Under the influence of both,their mental health may be suffering from“double disadvantage”.So,based on an ecological model of the stress process,this paper tries to use the data of the questionnaire on the mental health of mobile young white-collar workers in Zhejiang Province to explore the influence of some factors in the middle workplace and residence place on the mental health of micro individuals.The results show that:(1)The working environment with high control and low freedom and the workplace discrimination against the mobile status will have a negative impact on the mental health of mobile young white-collar workers;(2)Financial anxiety in daily life will lead to a decline in the mental health level of mobile young white-collar workers;(3)Good organizational support and neighborhood social relations can significantly relieve life pressure,so as to effectively improve the mental health of mobile young white-collar workers.It can be seen that we also need to pay more attention to the mental health of mobile young white-collar workers in order to improve their situation.
基金funding support from the National Natural Science Foundation of China(NSFC)(Grant Nos.41941018 and 52304111)the Program of China Scholarship Council(Grant No.202206430007).
文摘To overcome large deformation of deep phosphate rock roadways and pillar damage,a new type of constant-resistance large-deformation negative Poisson’s ratio(NPR)bolt that can withstand a high prestress of at least 130 KN was developed.In the conducted tests,the amount of deformation was 200-2000 mm,the breaking force reached 350 KN,and a high constant-resistance pre-stress was maintained during the deformation process.A stress compensation theory of phosphate rock excavation based on NPR bolts is proposed together with a balance system for bolt compensation of the time-space effect and high NPR pre-stress.Traditional split-set rock bolts are unable to maintain the stability of roadway roofs and pillars.To verify the support effect of the proposed bolt,field tests were conducted using both the proposed NPR bolts and split-set rock bolts as support systems on the same mining face.In addition,the stress compensation mechanism of roadway mining was simulated using the particle flow code in three dimensions(PFC^(3D))-fast Lagrangian analysis of continua(FLAC^(3D))particle-flow coupling numerical model.On-site monitoring and numerical simulations showed that the NPR excavation compensation support scheme effectively improves the stress state of the bolts and reduces the deformation of the surrounding rock.Compared to the original support scheme,the final deformation of the surrounding rock was reduced by approximately 70%.These results significantly contribute to domestic and foreign research on phosphate-rock NPR compensation support technology,theoretical systems,and engineering practices,and further promote technological innovation in the phosphate rock mining industry.
基金supported by National Natural Science Foundation of China(51974166).
文摘Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application in the future,the thermal stability of this substance during storage,transportation,and use will become quite important.Thus,in this work,the thermal decomposition behavior,thermal decomposition kinetics,and thermal hazard of ADCA were investigated.Experiments were conducted by using a SENSYS evo DSC device.A combination of differential iso-conversion method,compensation parameter method,and nonlinear fitting evaluation were also used to analyze thermal kinetics and mechanism of ADCA decomposition.The results show that when conversion rate α increases,the activation energies of ADCA's first and main decomposition peaks fall.The amount of heat released during decomposition varies between 182.46 and 231.16 J·g^(-1).The proposed kinetic equation is based on the Avrami-Erofeev model,which is consistent with the decomposition progress.Applying the Frank-Kamenetskii model,a calculated self-accelerating decomposition temperature of 287.0℃is obtained.
基金funded by the National Natural Science Foundation of China(Grant Number 52075361)Shanxi Province Science and Technology Major Project(Grant Number 20201102003)+3 种基金Lvliang Science and Technology Guidance Special Key R&D Project(Grant Number 2022XDHZ08)National Natural Science Foundation of China(Grant Number 51905367)Shanxi Natural Science Foundation General Project(Grant Numbers 202103021224271,202203021211201)Shanxi Province Key Research and Development Plan(Grant Number 202102020101013).
文摘In the fiber winding process,strong disturbance,uncertainty,strong coupling,and fiber friction complicate the winding constant tension control.In order to effectively reduce the influence of these problems on the tension output,this paper proposed a tension fluctuation rejection strategy based on feedforward compensation.In addition to the bias harmonic curve of the unknown state,the tension fluctuation also contains the influence of bounded noise.A tension fluctuation observer(TFO)is designed to cancel the uncertain periodic signal,in which the frequency generator is used to estimate the critical parameter information.Then,the fluctuation signal is reconstructed by a third-order auxiliary filter.The estimated signal feedforward compensates for the actual tension fluctuation.Furthermore,a time-varying parameters fractional-order PID controller(TPFOPID)is realized to attenuate the bounded noise in the fluctuation.Finally,TPFOPID is enhanced by TFO and applied to control a tension control system considering multi-source disturbances.The stability of the method is analyzed by using the Lyapunov theorem.Finally,numerical simulations verify that the proposed scheme improves the tracking ability and robustness of the system in response to tension fluctuations.
文摘BACKGROUND Violence against healthcare workers(HCWs)in the Caribbean continues to prevail yet remains underreported.Our aim is to determine the cause,traits,and consequences of violence on HCWs in the Caribbean.AIM To determine the cause,traits,and consequences of violence on HCWs in the Caribbean.METHODS This research adopted an online cross-sectional survey approach,spanning over eight weeks(between June 6th and August 9th,2022).The survey was generated using Research Electronic Data Capture forms and followed a snowballing strategy to contact individuals using emails,social media,text messages,etc.Logistic regression analysis was performed to evaluate the variables that influence violence,including gender,age,years of experience,institution type,and night shift frequency.RESULTS The survey was completed by 225 HCWs.Females comprised 61%.Over 51%of respondents belonged to the 21 to 35 age group.Dominica(n=61),Haiti(n=50),and Grenada(n=31)had the most responses.Most HCWs(49%)worked for government academic institutions,followed by community hospitals(23%).Medical students(32%),followed by attending physicians(22%),and others(16%)comprised the most common cadre of respondents.About 39%of the participants reported experiencing violence themselves,and 18%reported violence against colleague(s).Verbal violence(48%),emotional abuse(24%),and physical misconduct(14%)were the most common types of violence.Nearly 63%of respondents identified patients or their relatives as the most frequent aggressors.Univariate logistic regression analyses demonstrated that female gender(OR=2.08;95%CI:1.16-3.76,P=0.014)and higher frequency of night shifts(OR=2.22;95%CI:1.08-4.58,P=0.030)were associated with significantly higher odds of experiencing violence.More than 50%of HCWs felt less motivated and had decreased job satisfaction post-violent conduct.CONCLUSION A large proportion of HCWS in the Caribbean are exposed to violence,yet the phenomenon remains underreported.As a result,HCWs’job satisfaction has diminished.
基金Supported by National Excellent Natural Science Foundation of China(Grant No.52122503)Hebei Provincial Natural Science Foundation of China(Grant No.E2022203002)+2 种基金The Yanzhao’s Young Scientist Project of China(Grant No.E2023203258)Science Research Project of Hebei Education Department of China(Grant No.BJK2022060)Hebei Provincial Graduate Innovation Funding Project of China(Grant No.CXZZSS2022129).
文摘Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ratio.However,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy losses.By contrast,pump control systems offer a high efficiency.Nevertheless,their response ability is unsatisfactory.To fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(PCDS)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of robots.Herein,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the PCDS force control system is first introduced.In addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC herein.This method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the system.Finally,experimental verification is performed using the PCDS performance test platform.The experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the PCDS.The relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot.