A Novel Model for Describing Rail Weld Irregularities and Predicting Wheel-Rail Forces Using a Machine Learning Approach

Rail weld irregularities are one of the primary excitation sources for vehicle-track interaction dynamics in modern high-speed railways.They can cause significant wheel-rail dynamic interactions,leading to wheel-rail noise,component damage,and deterioration.Few researchers have employed the vehicle-track interaction dynamic model to study the dynamic interactions between wheel and rail induced by rail weld geometry irregularities.However,the cosine wave model used to simulate rail weld irregularities mainly focuses on the maximum value and neglects the geometric shape.In this study,novel theoretical models were developed for three categories of rail weld irregularities,based on measurements of the high-speed railway from Beijing to Shanghai.The vertical dynamic forces in the time and frequency domains were compared under different running speeds.These forces generated by the rail weld irregularities that were measured and modeled,respectively,were compared to validate the accuracy of the proposed model.Finally,based on the numerical study,the impact force due to rail weld irrregularity is modeled using an Artificial Neural Network(ANN),and the optimum combination of parameters for this model is found.The results showed that the proposed model provided a more accurate wheel/rail dynamic evaluation caused by rail weld irregularities than that established in the literature.The ANN model used in this paper can effectively predict the impact force due to rail weld irrregularity while reducing the computation time.

Evolution of undeformed chip thickness and grinding forces in grinding of K4002 nickel-based superalloy using corundum abrasive wheels

The undeformed chip thickness and grinding force are key parameters for revealing the material removal mechanism in the grinding process.However,they are difficult to be well expressed due to the ununiformed protrusion height and random position distribution of abrasive grains on the abrasive wheel surface.This study investigated the distribution of undeformed chip thickness and grinding force considering the non-uniform characteristics of abrasive wheel in the grinding of K4002 nickel-based superalloy.First,a novel grinding force model was established through a kinematic-geometric analysis and a grain-workpiece contact analysis.Then,a series of grinding experiments were conducted for verifying the model.The results indicate that the distribution of undeformed chip thickness is highly consistent with the Gaussian distribution formula.The increase in the grinding depth mainly leads to an increase in the average value of Gaussian distribution.On the contrary,the increase in the workpiece infeed speed or the decrease in the grinding speed mainly increases the standard deviation of Gaussian distribution.The average and maximum errors of the grinding force model are 4.9%and 14.6%respectively,indicating that the model is of high predication accuracy.

Regional Collaborative Innovation Advances the Development of New Quality Productive Forces: The Theoretical Basis and Paths to Realization

In the context of the new technological revolution,a leap in productivity is reflected in the shift from traditional productive forces to the new quality innovation-driven productive forces.In this leap,regional collaborative innovation plays an important role and significantly advances the vigorous development of new quality productive forces.On the Chinese path to modernization,new quality productive forces are characterized by“three innovations,”“three industrial dynamics,”and“three transformations.”Regional collaborative innovation can provide the impetus for major key technological breakthroughs,the building of technological innovation platforms,the facilitation of scientific and technological research and development and the commercialization of scientific and technological achievements,improvement in the training and exchange of technological innovation talents,innovations in the technological institutions and mechanisms,and the fostering of an integrated and open innovation ecosystem to promote the“three innovations,”“three industrial dynamics,”and“three transformations,”and thereby contribute to the development of new quality productive forces.

Self-assembly of perovskite nanocrystals:From driving forces to applications

Self-assembly of metal halide perovskite nanocrystals(NCs)into superlattices can exhibit unique collective properties,which have significant application values in the display,detector,and solar cell field.This review discusses the driving forces behind the self-assembly process of perovskite NCs,and the commonly used self-assembly methods and different self-assembly structures are detailed.Subsequently,we summarize the collective optoelectronic properties and application areas of perovskite superlattice structures.Finally,we conclude with an outlook on the potential issues and future challenges in developing perovskite NCs.

Numerical Simulations of Wave Impact Forces on the Open-Type Sea Access Road Using A Two-Phase SPH Model

A numerical study based on a two-dimensional two-phase SPH(Smoothed Particle Hydrodynamics)model to analyze the action of water waves on open-type sea access roads is presented.The study is a continuation of the analyses presented by Chen et al.(2022),in which the sea access roads are semi-immersed.In this new configuration,the sea access roads are placed above the still water level,therefore the presence of the air phase becomes a relevant issue in the determination of the wave forces acting on the structures.Indeed,the comparison of wave forces on the open-type sea access roads obtained from the single and two-phase SPH models with the experimental results shows that the latter are in much better agreement.So in the numerical simulations,a two-phaseδ-SPH model is adopted to investigate the dynamical problems.Based on the numerical results,the maximum horizontal and uplifting wave forces acting on the sea access roads are analyzed by considering different wave conditions and geometries of the structures.In particular,the presence of the girder is analyzed and the differences in the wave forces due to the air cushion effects which are created below the structure are highlighted.

Predicting impact forces on pipelines from deep-sea fluidized slides:A comprehensive review of key factors

Deep-sea pipelines play a pivotal role in seabed mineral resource development,global energy and resource supply provision,network communication,and environmental protection.However,the placement of these pipelines on the seabed surface exposes them to potential risks arising from the complex deep-sea hydrodynamic and geological environment,particularly submarine slides.Historical incidents have highlighted the substantial damage to pipelines due to slides.Specifically,deep-sea fluidized slides(in a debris/mud flow or turbidity current physical state),characterized by high speed,pose a significant threat.Accurately assessing the impact forces exerted on pipelines by fluidized submarine slides is crucial for ensuring pipeline safety.This study aimed to provide a comprehensive overview of recent advancements in understanding pipeline impact forces caused by fluidized deep-sea slides,thereby identifying key factors and corresponding mechanisms that influence pipeline impact forces.These factors include the velocity,density,and shear behavior of deep-sea fluidized slides,as well as the geometry,stiffness,self-weight,and mechanical model of pipelines.Additionally,the interface contact conditions and spatial relations were examined within the context of deep-sea slides and their interactions with pipelines.Building upon a thorough review of these achievements,future directions were proposed for assessing and characterizing the key factors affecting slide impact loading on pipelines.A comprehensive understanding of these results is essential for the sustainable development of deep-sea pipeline projects associated with seabed resource development and the implementation of disaster prevention measures.

Culturally competent care across borders: Implementing culturally responsive teaching for nurses in diverse workforces

The migration of healthcare professionals,including nurses,is a global phenomenon.It is driven by various factors,including the pursuit of better opportunities,living conditions,and professional development,as well as political instability or conflict in their home countries.The World Health Organization(WHO)has noted that high-income countries often rely on foreign-trained nurses to fill gaps in their healthcare systems[1].For instance,as of 2021,over 40%(52 million)of all nurses in the United States(US)were expatriates[2].In the United Kingdom(UK),the percentage of expatriate nurses was even higher,reaching approximately 18%in 2021[3].Owing to globalization and migration,healthcare providers must possess cultural competence to deliver improved care[4,5].Culturally responsive teaching(CRT)is rooted in the idea that culture plays a vital role in shaping people’s behaviors,beliefs,values,and communication styles[6].Furthermore,these cultural factors influence patients’perspectives on health,illness,healing,and their preferences for care and communication[7].By recognizing and embracing these cultural differences,nurses can provide more effective and compassionate care to their diverse patient population[8].

Nocturnal sentry duty and cardiometabolic characteristics in armed forces personnel

BACKGROUND Sleep deprivation can lead to increased body weight and blood pressure(BP),but the latent effects of partial sleep deprivation related to required night sentry duties within a short-term period on cardiometabolic characteristic changes in military personnel are unclear.AIM To investigate the association between night sentry duty frequency in the past 3 months and cardiometabolic characteristics in armed forces personnel.METHODS A total of 867 armed forces personnel who were aged 18-39 years and did not take any antihypertensive medications in Taiwan in 2020 were included.The frequency of night sentry duty was self-reported via a questionnaire(average number of night sentry shifts per month for the past 3 months).Hemodynamic status was assessed via the resting BP and pulse rate(PR).Cardiometabolic risk factors were defined according to the International Diabetes Federation criteria.Multivariable linear regression analyses of the associations between night sentry duties and PR,BP,and other metabolic syndrome(MetS)marker levels were performed,with adjustments for age,sex,substance use,body mass index and aerobic fitness.Multiple logistic regression analysis was carried out to determine the associations between night sentry duties and the prevalence of each MetS feature.

Numerical Simulation of Hydrodynamic Forces Acting on Curved Shape Trash Intercepting Net in Nuclear Power Plant Under Regular Waves

The occurrence of blockages of trash intercepting net in nuclear power plant due to marine biofouling has become increasingly frequent,leading to significant changes in the mechanical state.This paper establishes a CFD(Computational Fluid Dynamics)model to simulate the hydrodynamic forces of trash intercepting net under the action of regular waves.The porous media model is used to calculate the hydrodynamic forces,and the maximum mooring load is also evaluated.The simplified calculation method considering the different curved shape based on the flat nets are proposed,and the influences of wave parameters,solidity,and curved shape are investigated.The results indicate that under the regular wave conditions,as the solidity increases,the phenomenon of secondary wave peaks becomes more pronounced.The horizontal wave force reduction coefficient follows a three-piecewise linear relationship with the non-dimensional deformation level of curved shape.The trash intercepting net exhibits more potent scattering effects on short-wave conditions,displaying significant non-linear characteristics.The deformation level of the trash intercepting net is a significant factor influencing the mooring load.

International Perspective of Understanding the New Quality Productive Forces

Developing the new quality productive forces is an inherent requirement and an important focus for promoting high-quality development. However, it is not enough to understand the whole picture merely from a domestic perspective. The concept of new quality productive forces was put forward due to the changes in the international environment, including the emergence of anti-globalization trends and the economic policies of some major economies that are less open than before. With the changes in the global economic concept, China's economic development needs its innovative theory. As the world's second-largest economy, China is committed to the development of new quality productive forces and will make significant contributions to global development. In theory, it shows direction for the development of new quality productive forces on a global scale. In practice, it provides experiences for other economies to develop new quality productive forces. It also helps address the common challenges facing global development. The competition between major countries in traditional fields will continue, but in the case of the development of new quality productive forces, it will show some new characteristics. It will be more reflected in the field of strategic emerging industries, the confrontation risk in major country rivalry will be reduced, and strategic planning and design will become more important.

Implications of the Development of Agricultural Research Institutes from the Perspective of New Quality Productive Forces

Combining with the important exposition of general secretary Xi Jinping on the development of new quality productive forces,this paper discusses the connotation and development requirements of new quality productive forces in agriculture,and reveals the relationship between the development of new quality productive forces and the professional work of scientific research institutes.On this basis,some policy recommendations are put forward for agricultural research institutes to develop new quality productive forces.

Post-Traumatic Stress Disorder among Defence and Security Forces in Northern Benin (2023)

Introduction: Post-traumatic stress disorder (PTSD) is defined as “actual exposure to death or the threat of death, serious injury or sexual violence”, either directly or indirectly, resulting in a symptomatic procession of repetition, avoidance, neurovegetative hyperactivity and individualized symptoms, with or without negative cognitive and mood changes. It therefore goes without saying that the defence and security forces constitute a high-risk population in need of attention. Objective: To study post-traumatic stress disorder in defence and security forces in the city of Parakou in 2023. Methods: Descriptive cross-sectional study conducted from December 2022 to July 2023. The study population consisted of active military, republican police and firefighters in the city of Parakou in 2023. Non-proportional stratified sampling was used, given the inaccessibility of the source population size for national security reasons. Post-traumatic stress disorder was assessed using the “post-traumatic stress disorder checklist-5 (PCLS-5) scale. Results: A total of 305 subjects participated in the survey. Males dominated 90.2%. The most represented corps was the Republican Police (41.6%), most of whom were non-commissioned officers (46.6%). The majority count between 11 and 20 years of service (48.9%), with 2 to 5 missions completed (67.5%). The calculated prevalence of post-traumatic stress disorder was 11.8%, based on the post-traumatic stress disorder checklist-5 (PCL-5). Of the 36 respondents with post-traumatic stress disorder, 20 (55.6%) had experienced an armed attack, 25 (69.4%) had witnessed a violent death, 18 (50.0%) had witnessed the agony of a colleague, 15 (41.7%) had been exposed to a fire or explosion, while 26 (72.2%) had been traumatized by physical and/or verbal aggression. 5 (13.9%) had consulted a specialist psychiatrist, while 6 (16.7%) were on medication and 26 (72.2%) used sport as a means of maintaining physical and mental health. Respectively 22 (61.1%) and 21 (58.3%) had definite symptoms of anxiety and depression. Multivariate analysis revealed a significant association between post-traumatic stress disorder and the following variables: total number of children ≤ 2 (p = 0.015), comorbidities such as arterial hypertension (p = 0.007), history of hepatitis (p = 0.017), work accidents (p = 0.016), alcohol dependence (p = 0.004), domestic violence (p = 0.004), psychological violence (p = 0.017) and anxiety disorders (p Conclusion: Defence and security personnel can also be prey to post-traumatic stress disorder (PTSD), which needs to be systematically taken into account when they are subjected to trauma in the course of their duties. Mental health should be an integral part of the periodic medical check-up objectives for defence and security forces throughout the country.

New Quality Productive Forces:New Hope for Economic Growth

On January 17,China announced a GDP growth rate of 5.2 percent for 2023,successfully reaching the major projected targets.In 2024,the Chinese economy will continue to seek progress while maintaining stability and provide great dynamism for the stability and recovery of the world economy.New quality productive forces will become a new driver for economic growth in China.

Factories of the Future--China and Thailand are embracing new productive forces through NEV cooperation

Chinese modernization has been benefiting its neighboring countries,with the Belt and Road Initiative(BRI)aligning with multiple development strategies of Thailand,including the economic development plan Thailand 4.0 as well as the Eastern Economic Corridor(EEC)which could serve as a complementary to the Guangdong-Hong Kong-Macao Greater Bay Area(the Greater Bay Area).

New Quality Productive Forces Spur Global Development

China’s new quality productive forces theory and actions are a Chinese solution for win-win cooperation and common development by sharing development opportunities.THE third plenary session of the 20th Central Committee of the Communist Party of China(CPC)in July was in the global spotlight for the reform measures it proposed to advance Chinese modernization.The plenum decided to improve the institutions and mechanisms for fostering new quality productive forces in line with local conditions and pinpointed the key areas.The reforms will give impetus to both China’s development and common global prosperity.China’s new quality productive forces theory and actions taken vis-à-vis them indicate the development path of Chinese socialism and are a Chinese solution for win-win cooperation and common development by sharing development opportunities.

Fostering New Productive Forces to Empower Drivers of New Growth

The latest CPC Central Committee plenum laid out measures to foster new and quality productive forces in pursuit of high-quality development.HIGH-quality development is China’s primary task in building a modern socialist country in all respects.For this purpose,at its third plenary session in July this year,the 20th Central Committee of the Communist Party of China(CPC)declared its resolve to“improve the institutions and mechanisms for fostering new quality productive forces in line with local conditions…Relevant rules and policies will be improved to accelerate the formation of relations of production that are more compatible with new quality productive forces,and to channel various types of advanced production factors toward the development of new quality productive forces.These steps will help realize a significant increase in total factor productivity.”

In the Era of New Quality Productive Forces,How Can Cosmetics Enterprises Go with the Trend?

In 2024,a new mode of high-quality development and revolutionary innovation with“new quality productive forces”as the core is sweeping rapidly across China,involving traditional,emerging,future and many other industries.There is no exception to cosmetics production.Tendency:New quality productive forces as a new topicThe new quality productive force,highlighting“innovation”and“quality”,is an advanced productivity ecology with high-technology,high-efficiency and high-quality features,which has broken through the traditional economic growth mode and productivity development path,and conforms to the new development philosophy.

NEW QUALITY PRODUCTIVE FORCES SPUR GLOBAL DEVELOPMENT

The third plenary session of the 20th Central Committee of the Communist Party of China(CPC)in July was in the global spotlight for the reform measures it proposed to advance Chinese modernization.The plenum decided to improve the institutions and mechanisms for fostering new quality productive forces in line with local conditions and pinpointed the key areas.

Game-Changing Forces

President Xi Jinping stressed at this year’s“Two Sessions”the importance of fostering new quality productive forces to generate high-quality development.THE C919,China’s self-developed large passenger aircraft,soared into the sky on its maiden commercial flight in May 2023,while the Adora Magic City,China’s first domestically built large cruiseship,set sail on its maiden voyage to northeast Asian destinations in January 2024.The country has achieved one technological breakthrough after another in its endeavor to generate new forces to power its economy.

Opportunities And Outlooks Embracing new quality productive forces

New quality productive forces refer to advanced productivity driven by revolutionary technological breakthroughs and empowered by digital technology.They are distinguished from conventional productive capacity which is supported by workshop flfloors,assembly lines,and modular technology.