Working Conditions Research Articles

Automatic recognition of excavator working cycles using supervised learning and motion data obtained from inertial measurement units (IMUs)

This paper proposes an automatic method for excavator working cycle recognition using supervised classification methods and motion information obtained from four inertial measurement units (IMUs) attached to moving parts of an excavator. Monitoring and analyzing tasks that have been performed by heavy-duty mobile machines (HDMMs) are significantly required to assist management teams in productivity and progress monitoring, efficient resource allocation, and scheduling. Nevertheless, traditional methods depend on human observations, which are costly, time-consuming, and error-prone. There is a lack of a method to automatically detect excavator major activities. In this paper, a data-driven method is presented to identify excavator activities, including loading, trenching, grading, and idling, using motion information, such as angular velocities and joint angles, obtained from moving parts, including swing body, boom, arm, and bucket. Firstly, a dataset lasting 3 h is collected using a medium-rated excavator. One experienced and one inexperienced operator performed tasks under different working conditions, such as different types of material, swing angle, digging depth, and weather conditions. Four classification methods, including support vector machine (SVM), k-nearest neighbor (KNN), decision tree (DT), and naive Bayes, are off-line trained. The results show that the proposed method can effectively identify excavator working cycles with a high accuracy of 99%. Finally, the impacts of parameters, such as time window, overlapping configuration, and feature selection methods, on the classification accuracy are comprehensively analyzed.

From destination choice to departure: analysing French tourists’ behaviours facing health risks from COVID-19

ABSTRACT During a pandemic, individuals react both cognitively and emotionally, leading them to adopt self-protective behaviours. Governments, meanwhile, face a delicate balancing act between safeguarding public health and mitigating the socioeconomic impact. In the tourism industry, this translates to reducing infection risk while minimizing mass cancellations. Past research suggests that providing updated information can help achieve these objectives. This study examines two pre-departure behaviours of French tourists in response to health risks from COVID-19: (1) seeking or not seeking information about COVID-19 indicators and protective measures at the chosen destination; (2) continuing with the planned stay or cancelling it. Seeking information and cancelling trips are voluntary actions driven by various factors, including tourists’ emotional state, particularly their worry about contracting and transmitting COVID-19. We find that worry motivates both behaviours, with worry about contracting exerting the strongest influence. Information-seeking, regardless of whether analysed as ordinal or nominal, tends to promote cancellations. This suggests a potential conflict between public health and tourism objectives. Our findings highlight the critical need for tourism managers to reassure tourists about health safety and tailor communication strategies accordingly. In this vein, we discuss some propositions that could be considered in the event of future pandemics.

Occupational Disease in New York State: The Political Economic Context.

In 1987 Landrigan and Markowitz co-authored a report entitled "Occupational Disease in New York State." They found that death and illness from occupational disease were common and that the costs of exposure to hazardous conditions warranted public funding for new occupational health infrastructure in New York State. A recent confirmatory report recognized a wider spectrum of contemporary hazards and emphasized how public health problems connect to work. These reports provide factual snapshots at 2 points in time, but they do not explain nor analyze the changing conditions they describe. Including macro-contexts such as globalization, financialization, and neoliberalism, this article demonstrates several unique occupational safety and health implications by clarifying key themes related to the state's role, especially regulation and healthcare delivery systems. Conclusions directly tie the trajectory of occupational disease to workers' collective ability to confront and roll back neoliberalism while pushing occupational disease out of its medical/science silo.

Investigation of a newly developed shear built-in valve type MR damper with high damping: Theories and experiments

Magnetorheological (MR) dampers are widely used as semi-active energy-dissipation devices in structural vibration control. Traditional MR dampers, particularly their working mode, often struggle to achieve a high damping force output and sometimes fail to meet the needs of practical engineering. Therefore, it is necessary to study MR dampers that can provide a high damping force. This study proposes an MR damper that combines a built-in shear valve with various working modes of shear extrusion. The damper generates a higher damping force by applying a current to the coils at different positions and altering its working mode. First, the ANSYS Maxwell software simulates the internal magnetic circuit of the damper to assess whether the magnetic field intensity distribution and circuit direction meet the design requirements. Analysis revealed that the internal magnetic circuit distribution was reasonable and satisfied the operating requirements of the damper. Furthermore, the mechanical models of the two working modes were derived based on the Bingham and double-viscous models. Finally, the accuracies of the mechanical models were verified experimentally. The experimental results showed that the simulation values closely matched the experimental values under all the working conditions. Therefore, the proposed mechanical models are reasonable, and can provide significant reference values for practical engineering applications.

Cultivating a psychological health and safety culture for interprofessional primary care teams through a co-created evidence-informed toolkit.

The psychological health and safety of healthcare workers workplaces and learning environments impacts the quality of healthcare services. To facilitate the psychological health and safety of interprofessional primary care teams, we curated a bilingual toolkit of 122 psychological health and safety resources comprising a multi-level categorization addressing individual, team, organization, and system-level interventions. The resources in the toolkit are organized by 7 themes, based on a clustering of the 15 psychosocial factors. Adopting the framework built on the 7 themes, this article describes the toolkit development process and how it addresses the key factors for psychologically healthy and safe workplaces to foster interprofessional collaboration. Implementation of the interventions in the toolkit is an important next step for which health system leadership is critical. Additionally, we identify several gaps and call on researchers, educators, and health leaders to address them in their future work.

Risk and protective factors of vulnerability to burnout and occupational health issues in university students: Is being excellent an advantage?

Risk and protective factors of vulnerability to burnout and occupational health issues in university students: Is being excellent an advantage?

Small data challenges for intelligent prognostics and health management: a review

Prognostics and health management (PHM) is critical for enhancing equipment reliability and reducing maintenance costs, and research on intelligent PHM has made significant progress driven by big data and deep learning techniques in recent years. However, complex working conditions and high-cost data collection inherent in real-world scenarios pose small-data challenges for the application of these methods. Given the urgent need for data-efficient PHM techniques in academia and industry, this paper aims to explore the fundamental concepts, ongoing research, and future trajectories of small data challenges in the PHM domain. This survey first elucidates the definition, causes, and impacts of small data on PHM tasks, and then analyzes the current mainstream approaches to solving small data problems, including data augmentation, transfer learning, and few-shot learning techniques, each of which has its advantages and disadvantages. In addition, this survey summarizes benchmark datasets and experimental paradigms to facilitate fair evaluations of diverse methodologies under small data conditions. Finally, some promising directions are pointed out to inspire future research.

A new Ti-Al-Cr-Mo-Zr titanium alloy welding wire：stability, microstructure and mechanical properties

In order to improve the plasticity of titanium alloy welded joints, relevant scholars currently focus primarily on studying the mechanism of action of alloying elements Mo and V, such as reducing the phase transition temperature of the welded seam and ensuring a certain amount of β phase residue in the welded seam. In addition to improving the stability and strengthening ability of titanium alloy welded joint, it can also maintain a certain degree of plasticity of the welded joint. However, the poor impact toughness is still the key problem that restricts its long-term stable service in the harsh environment. Our work designed and developed a new Ti-Al-Cr-Mo-Zr solid welding wire, with the synergistic effect of Al, Cr, Mo and Zr, the welded seam microstructure and grain can be refined while ensuring the enough stiffness of the welding wire and its flatness during wire feeding into the designated working area. It ensures good wetting and spreading flow performance of the liquid molten pool metal in the welding process, so better welded seam formation can be obtained. The relative contents of α' martensite and β phase in the welded seam are 76.79% and 23.21%, respectively. The residual β phase is interspersed between the α' martensite of the slats. The β phase provides a path for the plastic deformation of the welded joint, making it easier for dislocation slip to pass the β/α' interface. At the same time, more dislocation slip channels and a small number of fine twins can be found in the interior of α' martensite, which can ensure the strength while taking into account the toughness. After testing, it is found that the average tensile strength of welded joints is 901 MPa, which is close to 95% of the base metal(BM), the average post-fracture elongation of welded joints is 21%, and the impact toughness value at room temperature is distributed between 25J and 33J, which meets the requirements of the synergistic effect of welded joint strength and plastic toughness. It is suitable for long-term stable service of Ti64 titanium alloy welding structure under harsh working conditions.

Breastfeeding among women employed in Mexico’s informal sector: strategies to overcome key barriers

BackgroundRates of exclusive breastfeeding fall below recommended levels, particularly among women in paid employment. In Mexico, more than half of women are in informal employment, meaning they lack many of the protections that may support breastfeeding.MethodsIn-depth interviews with 15 key informants representing government agencies (n = 6 organizations), NGOs (n = 4), international organizations (n = 2), and academia (n = 2) in Mexico. Interviews were conducted between March and June 2023. To understand and describe barriers to breastfeeding among informally employed women in Mexico according to key informants and the current and potential policies to address these barriers, we conducted a qualitative thematic analysis.ResultsCurrent policies to promote, protect, and support breastfeeding predominantly apply to all employed women, but respondents expressed concern that they did not provide adequate protection for women in informal employment. Additional themes concerned the need for relevant programs to be institutionalized and coordinated, discussions of breastfeeding as a right, and the legal equivalence (whether true in practice or not) of formal and informal workers.ConclusionsWomen employed in Mexico’s informal sector face a dearth of maternity protections. According to key informants, few policies exist to promote, protect, and support breastfeeding among employed women, in general, but the economic vulnerability and challenging working conditions of women in informal employment exacerbates their situation. The lack of access to formal labor protections, such as paid maternity leave, creates a significant barrier to breastfeeding for women in the informal sector. Recommendations include short-term policies to fill gaps in social protection for informally employed women, as well as longer-term solutions such as the development of universal social protection programs and supporting formalization.

Assessing and mitigating health risks of workers exposed to volatile organic compounds in contaminated soils during active pit excavation: accounting for exposure variability and uncertainty

Health risks to workers involved in the active pit excavation of volatile organic compound (VOC)-contaminated soils have been overlooked, despite the prevalence of ex-situ remediation practices in China. This study developed a new VOC exposure in pit excavation (VEPE) model that comprehensively accounts for the release of gas-phase VOCs in soil pores, surface volatilization of newly exposed agglomerates, and volatilization of newly exposed excavation pit bottom surfaces. Additionally, the model incorporates the concentration variation of soil contaminants, spatial heterogeneity of soil properties, and the variability and uncertainty of worker exposure using two-dimensional Monte Carlo simulation (2D MCS), highlighting the importance of controlling area of new exposure surfaces, soil saturation, and air exchange during the pit excavation to mitigate risks. The study evaluated worker-health-based risks during the excavation of a VOC-contaminated site in Beijing and revealed that the inhalation cancer risk for trichloroethylene (2.35×10-6) and its hazard quotient (143.92) exceed the acceptable levels (10-6 and 1.0, respectively). The comparison of models demonstrated the theoretical advancements of the VEPE model over existing pit excavation models, while the field test comparison showed a significant improvement in the predication accuracy. This study addresses the under-researched area of worker safety in contaminated excavation sites. The findings have the potential to promote cleaner and more sustainable practices in ex-situ contaminated site remediation by providing valuable insights for implementing effective control measures to mitigate the emission of toxic VOCs, thereby reducing adverse social and environmental impacts.

Investigating musculoskeletal risks in manual mushroom harvesting: An ergonomic field study in canadian farms

Canada's annual production of 132,000 metric tonnes of mushrooms relies on manual harvesting, posing risks of work-related musculoskeletal disorders (WMSDs). This study employs ergonomic evaluation techniques, including Rapid Upper Limb Assessment (RULA) and Cumulative Trauma Disorder (CTD) index, along with a discomfort assessment questionnaire, to analyze workers' postural loads and self-reported discomfort. Results indicate that immediate alterations are needed in 85% of picking postures to reduce WMSD risks (RULA score: 6–7). The overall process shows a CTD index of 1.16, indicating potential repetitive strain injuries. Pickers report discomfort, particularly in the hand and shoulder. The study underscores the need for alternatives like redesigned growing beds to enhance worker safety in mushroom harvesting.

Performance prediction and optimization of lateral exhaust hood based on back propagation neural network and genetic algorithm

The lateral exhaust hood (LEH) is commonly used to capture contaminated airflow in industrial plants. Its performance is influenced by numerous factors and exhibits a strong nonlinear relationship, optimizing this performance demands significant computational time and cost. This study proposes an LEH optimization design method that combines a backpropagation neural network (BPNN) with a genetic algorithm (GA), verified through experiments and numerical simulations. A BPNN prediction model is established based on 520 CFD simulation results. This study discusses seven factors influencing LEH performance, including the buoyant jet's velocity and temperature, the LEH's geometry and position, and the exhaust velocity. The results indicate that within the parameter range of the prediction model, there is a critical aspect ratio value that significantly affects LEH capture efficiency. The horizontal distance between the LEH and the pollution source significantly affects capture efficiency, especially when the LEH's installation height is low (H/D < 0.5). In addition, when combined with GA for fast searching, the expected combination of LEH design parameters can be obtained. This study aims to enhance the design efficiency of industrial exhaust hoods and improve worker health protection.

Coping within the interstices of the neoliberal sports market: Using de Certeau to analyse the migration of African mixed martial arts fighters in South Africa

This paper focuses on African migrant mixed martial arts (MMA) fighters enrolled in the Extreme Fighting Championship (EFC), a leading MMA organization established in 2009 in South Africa. It highlights their precarious work and living conditions, which are counterbalanced by the promise of real but rare career possibilities. Drawing from Michel de Certeau’s conceptual framework – notably his concepts of strategies, tactics and lieu propre (proper place) – we analyse what it is to struggle, cope and sometimes thrive, as a migrant fighter in South Africa. We rely on 61 semi-structured interviews with 35 professional EFC fighters from four Sub-Saharan countries who migrated to South Africa. Our results highlight the various tactics – which rely on social networks, their bodily stature, fighting skills and EFC media presence – that fighters mobilize to cope with the hardships of migratory status and unstable work conditions. We thus reveal the dialectic power relations that tie fighters to promoters and contribute to understanding migrants’ work conditions in the neoliberal sports market. Our research highlights the need to move away from migrant athletes’ caricatured representations as silent and passive victims unaware of the mechanisms of oppression to a more dynamic understanding of power relations that takes coping mechanisms and career trajectories into account.

Validating perceptions with clinical measures: A latent growth curve on the associations between patient experience and hospital-associated infections in Norway over time.

The aim of the study was to examine the parallel relationships between the growth rates of patient-reported experiences and hospital-associated infections (HAIs) over time. The study employed five waves (years) of data among hospitals across Norway from the Norwegian Health Directorate website for both patient experience and HAIs. The study employed a longitudinal design, testing and comparing different models. A latent growth curve model with autoregressions emerged as the best fit for the data. The data extracted from the website included 102 hospitals. However, the study used 61 hospitals after data cleaning, each with 400 patient respondents for each year. The results showed that for both patient experiences and HAIs, hospitals that recorded higher scores at the starting point experienced a lower growth rate over time compared to hospitals that recorded lower infections at the starting point. Second, it was found that the starting point for patient experience significantly related to the starting point for HAIs, such that the higher the score for patient experience, the lower the score on infections across hospitals. The results also indicated that almost all lagged effects on either patient-reported experience or HAIs were significant. This study shows the significance of patient experience, not only for patient-reported outcomes but also for clinical outcomes. This thus ascertains the relevance of the patient experience pillar for the other pillars of quality health care, namely, clinical effectiveness and safety.

An adaptive approximation‐free control for leader‐follower tracking of multi‐agent systems with unknown nonlinearity and disturbance

AbstractDue to variable and complex work environments, nonlinearities, uncertainty and disturbances are inevitable in multi‐agent systems. Approximation‐free control can address these issues without involving approximators, such as fuzzy logic systems and neural networks. However, some issues like the singularity problem caused by the signals exceeding the preset boundary in changing work conditions still remain. This paper proposes an adaptive and reliable approximation‐free control, which comprises a novel singularity compensator and a modified transforming function. The proposed control scheme performs better in terms of convergence rate and overshoot, avoids issues relating to singularity, and has added flexibility in terms of parameter choice. The proposed control law adapts to changes in operating conditions and nonlinearities—the efficacy of which is demonstrated using simulations.

Implementacja systemów elektronicznych w szelkach bezpieczeństwa i urządzeniach samohamownych

Implementation of electronic systems in safety harnesses and self-braking devices The aim of this publication is to discusses issues related to the use of electronic systems in equipment protecting against falls from height. They are used both in the form of light and sound modules, as well as in the form of sets of sensors, detectors, data transmission blocks, or even entire complex electronic systems. These systems are used to improve work safety, and personal protective equipment equipped in this way is called intelligent. The aim of the article is also to present the prototype of a self-locking device for the dynamic shortening of the fall path. The electronic-mechanical locking system in the self-locking device, developed at the Central Institute for Labour Protection – National Research Institute, allows for its dynamic activation, independent of the external energy generated during the fall of a person. Thanks to this construction, it is possible to reduce the free fall path, and thus the forces acting on a person when stopping him, as well as work the self-locking device in a horizontal or close to a horizontal position and use it as a device preventing the start of a fall. The construction and operation of the designed device were shown, and the possibilities of its use were presented in the article. Keywords: work at height, fall protection equipment, control electronic systems, intelligent personal protective equipment

A hybrid semantic attribute-based zero-shot learning model for bearing fault diagnosis under unknown working conditions

Most current intelligent fault diagnosis models, dependent on specific working condition data for training, cannot effectively diagnose faults in unknown working conditions without data. Zero-shot learning (ZSL) can identify samples unseen during the training phase and has now been applied to the field of fault diagnosis. However, effective methods for constructing fault semantics in unknown conditions for zero-shot fault diagnosis are still lacking. This paper proposes a hybrid semantic attribute-based zero-shot learning model (HSAZLM) to address this issue. A novel approach to constructing the semantic space is introduced by combining manually defined semantic attributes (SA) with non-semantic attributes (NSA) to form hybrid semantic attributes (HSA). This addresses the issue of insufficient semantic information due to limitations in expert knowledge when defining SA. In the hybrid semantic attribute construction module, a denoising residual convolutional autoencoder (DRCAE) is employed as a semantic learning model to acquire NSA containing high-dimensional abstract features, enhancing the model's generalization and robustness. To verify the effectiveness and superiority of the proposed HSAZLM, experiments were conducted on both a publicly available bearing dataset and a self-built bearing dataset. The average accuracy rates are 96.82% and 96.42% respectively, exceeding the current state-of-the-art methods.

Patient safety culture perceptions among dentists in the eastern region of Saudi Arabia

ObjectiveSafe patient care can help reduce treatment costs, morbidity, and mortality. This study aimed to assess dentists’ perceptions of patient safety culture and related factors in the Eastern region of Saudi Arabia.MethodsThis cross-sectional study used a sample of 271 dental professionals working in private and public dental hospitals and clinics in the Eastern region of Saudi Arabia. The Safety Attitude Questionnaire (SAQ), a validated tool consisting of 36 items on a 5-point Likert scale, was used to assess dentists’ perceptions of patient safety culture. The score of SAQ ranges from 0 to 100 and a cut-off ≥ 75 is considered a positive attitude toward patient safety culture.ResultsThere were 53.9% males and 46.1% females in the study with a mean age of 35.56 ± 6.87 years. Almost half of the participants (52%) attended a course on patient safety and 22.1% experienced medical error in the last month. The mean score of the SAQ of the sample was 65.14 ± 13.03 and the patient safety score was significantly related to the marital status (P = 0.041), attendance of patient safety course (P < 0.001), and experience of medical error (P = 0.008). The highest mean score (73.27 ± 20.11) was for the job satisfaction domain, followed by the safety climate domain (67.69 ± 16.68), and working conditions domain (66.51 ± 20.43). About one-quarter of the participants (22.5%) demonstrated positive attitudes toward patient safety culture. Multiple logistic regression analysis showed that dental professionals who attended a patient safety course were 4.64 times more likely to demonstrate positive attitudes toward patient safety than those who did not attend a course (P < 0.001).ConclusionThis study showed that patient safety culture was significantly related to the attendance of safety courses, marital status, and experiencing medical error. About one out of four dental professionals demonstrated a positive attitude towards patient safety culture which was significantly associated with the attendance of the safety course.

The concentration and probabilistic health risk assessment attribute to PAHs in indoor air of Hormozgan aluminum plant, Iran

ABSTRACT We measured PAHs concentrations to understand the potential short and long-term health risks to workers. In the anode cooking area, the lowest and highest concentrations of PAHs were found for DahA (dibenzo[a,h]anthracene) at 0.373 ± 0.326 µg/m3 and Chry (chrysene) at 1.923 ± 1.258 µg/m3, respectively. In the anode-making area, these concentrations were higher, with DahA at 0.435 ± 0.221 µg/m3 and Chry peaking at 3.841 ± 1.702 µg/m3. Risk assessment based on these concentrations indicates a hierarchical order of individual PAHs risks in the anode cooking area, led by BaP (benzo[a]pyrene), followed by other specific PAHs compounds. The total hazard quotient (THQ) for PAH exposure in both anode-making and cooking areas significantly exceeds the threshold for considered cancer risk, emphasizing the considerable danger to workers. This study underscores the urgent need to mitigate exposure to PAHs in industrial settings to protect worker health from the carcinogenic risks of such hazardous compounds.

Quantifying work-related social inequalities in life expectancy: a methodological proof-of-concept.

Employment and working conditions are strong social determinants of health, yet many epidemiological studies fail to account for their impact on life expectancy calculations. Integration of working conditions into health estimates requires both valid methodology and data sources. Using the French National Health and Career Path survey and French life tables, we quantified the impact of four major work-related factors (lack of job control, job insecurity, unemployment, and occupational physical activity) in explaining socio-occupational inequalities in life expectancy. Using a formula-based approach, we computed work-related loss in life expectancy by socio-occupational group separately by sex. Based on life expectancy at age 35, we estimated a range from 1.3 to 3.3 years of life lost for men, and from 0.5 to 1.8 years for women are attributed to a combination of these four key factors. Although subject to sources of under- and over-estimation, the differential life expectancy at age 35 between senior executives and manual workers would substantially decrease, had these exposures been set at the theoretical minimum level. This proof-of-concept analysis demonstrates the utility of accounting for occupational factors and the potential to quantify the improvements in life expectancy by modifying working and employment conditions.