bluuebunny/crossref_metadata_2025 huggingface dataset:
Simply Effective? Simplified User Interfaces in Software Tutorials
Authors: Bsdurrek Pia , Meng Michael
Published: July 2024

Simplified user interfaces (SUIs) refer to a new design technique in technical communication that simplifies screenshots by removing irrelevant elements and highlighting only the essential information. While there is consensus on the benefits of signaling in multimedia learning, there is currently no empirical evidence on the effects of SUIs on user performance. This study reports an eye-tracking experiment that examined whether users can work more effectively and efficiently with a software tutorial containing SUIs instead of unedited pictures without signaling or pictures using conventional signaling techniques. The study also aimed to clarify whether SUIs draw user attention to relevant areas of a picture. Eye tracking and performance measures indicate that SUIs draw user attention successfully, but do not improve user performance compared to unedited screenshot in a tutorial scenario. The results contribute to the question of whether design principles of multimedia learning can be successfully transferred to action-oriented texts.
Book review: Ritajyoti Bandyopadhyay. 2022. Streets in Motion: The Making of Infrastructure, Property, and Political Culture in Twentieth-century Calcutta
Authors: Chatterjee Anasua
Published: July 2024

Ritajyoti Bandyopadhyay. 2022. Streets in Motion: The Making of Infrastructure, Property, and Political Culture in Twentieth-century Calcutta. Cambridge: Cambridge University Press. xiv + 305 pp. Maps, tables, appendices, images, glossary, bibliography, index. $99.99 (hardback—ISBN: 9781009100113)
Regulating Sweets in Bengal: Control Orders and Their Afterlife
Authors: Dey Ishita
Published: July 2024

Sweets, especially milk-based sweets, are considered to be a ubiquitous part of Bengali cuisine. In March 2020, amidst the lockdown, the Government of West Bengal designated hours during the day for sweet shops to operate to avoid wasting milk. Such state notifications constitute an important site to study how legal meanings of sweetness revolve around the idea of ‘essential commodities’. Through a close reading of the Control Orders issued by the Government of West Bengal in the 1960s I show how the statist measures to ensure the supply of milk, an essential commodity, extend to not only the commodity itself but also the products—in this case, sweets. Control Orders, follow-up court cases, newspaper debates and the state’s attempt to create a compassionate lobby through a much-publicised speech on All India Radio show how the legal meanings of sweets—as wastage of milk vs. cultural logic of sweetness, as an integral part of Bengali life—come into play. I show that Control Orders work with lists, one of the classic modes of documentation, and I argue that by listing milk as essential the Control Orders ended up listing milk products—especially chhana, as excess—and regulating sweets.
Caste-based Lists and Fading Maps: Bureaucratic Anxiety and Shifting Landscapes in the Himalayan Uttarakhand after the 2013 Flash Floods
Authors: Mathson Gideon Thomas
Published: July 2024

In 2013, floods in the state of Uttarakhand, particularly in its Himalayan district of Rudraprayag, led to landslides, rockfall and landslips. To calculate compensation and provide restitution at the village level, the state administration had to verify land ownership. However, since the most recent revenue settlement was conducted in 1967, the administration had to rely on faded maps and guesswork, and they used caste-based procedures and lists. The process created bureaucratic anxiety, fuelled by an affective excess to the given paradigm of bureaucratic embodiment and procedure (described by Nayanika Mathur as the ‘Sarkari affect’). By bureaucratic anxiety here I am using a modified Lacanian formulation implying the absence of a knowledge of the other’s desire, in this case, the desire of the state. Post-disaster governance in Kedarnath creates the sense of an invisibility of the state order, which becomes opaque and difficult to gauge. Using graphic artefacts I show how gaps in the administrative framework created an interpretive space between state and citizen, how this space was mortified by the manner in which the compensation process was carried out and how such mortification affected the community’s potential to use bureaucratic gaps to create a network of subjectivity that is actively involved in its own world-making.
A novel remaining useful life prediction method based on gated recurrent unit network optimized by tunicate swarm algorithm for lithium-ion batteries
Authors: Zhai Qianchun , Sun Jing , Shang Yunlong , Wang Haofan
Published: July 2024

Lithium-ion batteries have a wide range of applications in the field of new energy vehicles with advantages including small size, high efficiency, and low pollution. Accurate prediction of the remaining useful life (RUL) of lithium-ion batteries is particularly important to reduce unintended maintenance and avoid safety incidents caused by battery aging. To improve the accuracy and robustness of the RUL prediction of lithium-ion batteries, a prediction method is proposed based on gated recurrent unit (GRU) network optimized by tunicate swarm algorithm (TSA) in this paper. First, the capacity data during the life cycle of the aging battery are extracted as the prediction feature. Then, the GRU network is used to capture the dependencies between degraded capacities for RUL prediction. The main hyperparameters in the GRU network are optimized by the TSA to maximize the prediction performance. Finally, to ensure the validity and generalizability of the proposed RUL prediction method, data sets from University of Maryland, National Aeronautics and Space Administration (NASA), and our own laboratory are selected for validation. The superiority of the proposed method is verified by comparison with other different prediction methods.
Multipoint temperature model predictive control with improved MOEA/D
Authors: Li Mingyu , Liu Ruirong , Wu Pulei , Wang Jianguo
Published: July 2024

Model predictive control (MPC) algorithm which can predict future states and generate accurate control sequences is adopted to control multiple measurement points collaboratively in a temperature system. To carry out the multiobjective optimization problem (MOP) according to MPC, multiobjective evolutionary algorithms based on decomposition (MOEA/D) and its improved version have been employed. The improved MOEA/D algorithm was compared with its original version through simulation, and the practical effectiveness is verified by tests on a self-made dual-point temperature control system. Finally, the improved MOEA/D algorithm was embedded into the control system of the experimental device, and temperature-tracking control experiments were conducted. The results show that the algorithm applied here can simultaneously control the temperature of two points and keep them close to the target temperature curve. It helps optimize the multiobjective control by virtue of MPC, and particularly opens up new possibilities to achieve optimal temperature control in different engineering applications.
The Potential and Limits of Spontaneous Labor Activism on Social Media: The Search for Justice among Chinese Restaurant Workers
Authors: Wu Tommy
Published: July 2024

Recent scholarship on social media in labor activism has centered on institutions such as labor unions. What is understudied is how “unorganized” workers use social media to reclaim agency. Employing digital ethnography this study explores the use of WeChat, an all-in-one Chinese mobile application, among Chinese restaurant workers to share stories of mistreatment and deteriorating work conditions in the United States. Tracing the development of a blacklist of Chinese/Asian fusion restaurants that garnered the interest of tens of thousands of Chinese restaurant workers, this article reveals the potential and limitations of social media as a medium for labor activism.
Stabilisation of Thin Liquid Films by Polymer Additives
Authors: Yerushalmi-Rozen R. , Klein J.
Published: July 2024

Stability of thin films of non-volatile liquids is a key issue in a variety of applications. Often a film is forced to spread on a substrate which is not wetted by the liquid. The film then ruptures within minutes and dewets. Common methods for achieving stability include the introduction of surface-active low molecular weight agents, or modification of the chemistry of the substrate. We describe here a mechanism for suppressing the rupture of the films by surface-attached polymers together with trace amounts of free polymers in the bulk of the film. The effect may have a kinetic origin, which is related to the entanglement of free chains and surface-attached polymer chains, or it may be due to a modification of the thermodynamic interactions.
Stefan Müller-Doohm’s Habermas: A Biography: Critical Reflections
Authors: Kellner Douglas
Published: July 2024

In my engagement with Stefan Müller-Doohm’s Habermas: A Biography, I argue that Müller-Doohm presents Habermas’s life and theoretical development, demonstrating a line of continuity through Habermas’s first published book on the public sphere to his later work on communicative action, and how this theme provides a guiding thread throughout Habermas’s work and constitutes one of his major contributions to contemporary theory, which is also highly relevant to and intersects with Habermas’s activism. Further, he documents Habermas’s trajectory from his early theoretical works through his linguistic turn to the present. The study demonstrates how Habermas’s philosophical work from his early theory of the public sphere to his linguistic turn establishes Habermas’s theme of communicative action as a major philosophical contribution which has relevance for the many theoretical and political texts Habermas has produced in his long, distinguished, and immensely productive career. Yet, in a concluding critical section, I argue that Müller-Doohm does not adequately engage with Habermas’s theoretical conceptions, downplaying his philosophical achievements while failing to explore relevant theoretical literature and philosophical debates on Habermas that have accompanied his work for decades.
Impact of calcination temperature on optimized NiO anode synthesis for batteries
Authors: Kumchompoo Jaturon , Moonla Chochanon , Ouiram Tik
Published: July 2024

In this research, NiO, a vital transition metal known for its excellent electrochemical properties, was successfully synthesized under alkaline conditions using the precipitation method. Alterations in calcination temperatures between 720 and 800°C in an argon atmosphere yielded different NiO crystal sizes. The smallest crystals, obtained at 760°C, exhibited the highest specific capacity, reaching 991.2 mAh g–1 at 0.5 C. The NiO electrode showed an impressive capacitance retention rate of approximately 98% over 300 cycles. This method offers high-performance NiO materials with extended life cycles, making it a strong candidate for use in lithium-ion battery anodes. Using saturated potassium hydroxide (KOH) aids in nickel oxide precipitation, improving performance. Recyclable KOH enhances potential for large-scale anode material production.
Fast and robust learned single-view depth-aided monocular visual-inertial initialization
Authors: Merrill Nathaniel , Geneva Patrick , Katragadda Saimouli , Chen Chuchu , Huang Guoquan
Published: July 2024

In monocular visual-inertial navigation, it is desirable to initialize the system as quickly and robustly as possible. A state-of-the-art initialization method typically constructs a linear system to find a closed-form solution using the image features and inertial measurements and then refines the states with a nonlinear optimization. These methods generally require a few seconds of data, which however can be expedited (less than a second) by adding constraints from a robust but only up-to-scale monocular depth network in the nonlinear optimization. To further accelerate this process, in this work, we leverage the scale-less depth measurements instead in the linear initialization step that is performed prior to the nonlinear one, which only requires a single depth image for the first frame. Importantly, we show that the typical estimation of all feature states independently in the closed-form solution can be modeled as estimating only the scale and bias parameters of the learned depth map. As such, our formulation enables building a smaller minimal problem than the state of the art, which can be seamlessly integrated into RANSAC for robust estimation. Experiments show that our method has state-of-the-art initialization performance in simulation as well as on popular real-world datasets (TUM-VI, and EuRoC MAV). For the TUM-VI dataset in simulation as well as real-world, we demonstrate the superior initialization performance with only a 0.3 s window of data, which is the smallest ever reported, and validate that our method can initialize more often, robustly, and accurately in different challenging scenarios.
Analysis of properties and microstructure of ASTM 5% Ni steel used for cryogenic pressure vessel
Authors: Zhu Ying-guang , Yan Ping-yuan , Du Lin , Zhang Hong-liang , Hou Jia-ping , Zhong Li-li , Ma Hui-Xia
Published: July 2024

The influence of the QLT (quenching + lamellarizing + tempering) heat treatment process on the structure and properties of ASTM 5% Ni steel is analyzed. Using QLT heat treatment is to improve the cryogenic toughness of steel, which is generally just related to the reversed austenite. The present study deals with the analysis of the role of QLT heat treatment on structure transformation by researching the relationship among QLT, reversed austenite, and cryogenic toughness. After QLT heat treatment, the structure of ASTM 5% Ni steel transforms from coarse F + B to uniform and fine-tempered sorbite. Grain refinement and high dislocation density bring excellent comprehensive mechanical properties. Alloying elements influence the process and results of the phase transformation of austenite and martensite by getting into them to form new segregation structural units. The oscillographic impact results show that unstable crack growth does not occur during the fracture process. The fracture is upper platform type, which indicates that 5% Ni steel has good cryogenic crack arrest performance. Austenite is not found in the structure under X-ray and transmission electron microscope. The results of the electronic probe indicate the condition of creating conversed austenite is not met. So, the good low-temperature toughness is not from austenite but grain refinement and the increase of the ratio of the large angular grain boundary. This study not only provides proof that the QLT process is not the only factor in the forming of reversed austenite, but also gives inspiration that cryogenic toughness should not rely too much on the reversed austenite.
Study repeats findings demonstrating in-person instruction improves empathic awareness: Curriculum emphasizes literary narratives, narrative reasoning, person-to person interaction, and close reading
Authors: Kelly Cavenaugh , McKeage Kim
Published: July 2024

Despite the widely accepted importance of clinician empathy in quality healthcare, no occupational therapy-based pedagogy has consistently demonstrated the ability to improve the level of empathic awareness in students. In an effort to replicate 2020 findings that demonstrated the close reading of literary narratives improves empathic awareness in occupational therapy students ( p < 0.001), the study’s curriculum and methodology were repeated in 2021 and 2022. Results demonstrated that classes taught fully in-person repeated findings ( p < 0.001), while classes taught online (2021) did not ( p > 0.001). Study implications include the potential of an in-person curriculum that emphasizes literary narratives to facilitate empathic awareness in occupational therapy students, and the possible limitations of online instruction to foster greater understanding of client needs.
Defining geoeconomics amid shifts in global hegemony: Critical geographies of new international conjunctures
Authors: Sparke Matthew
Published: July 2024

Recent shifts in global hegemony make the need for critical geographical accounts of geoeconomics and geopolitics that much more critical. They underline that we need to come to terms with their dialectical relationships and tensions, doing so in relation to both underlying struggles over international hegemony and uneven capitalist development as well as in relation to all sorts of complex overlying socio-cultural formations. Critical geographers can combine their diverse approaches more effectively to do this analytical work by adapting recent forms of conjunctural analysis in urban, economic and regional geography.
Labour geography is tedious: Of contracts, grievances and the nitty-gritty of worker agency in United Farm Workers-era California
Authors: Mitchell Don
Published: July 2024

Responding to the oft-asked question, ‘what counts as labour’s agency?’ this paper engages with recent developments in labour geography to argue that labour geographers would benefit from paying close attention to the nitty-gritty struggles over – and not only for – the contract. Taking the case of the United Farm Workers’ efforts to administer its newly-won contracts in the agribusiness fields of California in the 1970s, it suggests that labour’s agency is often not just expressed, but made to count, in the midst of the most mundane – and often tedious – of circumstances, like late night-grievance procedure meetings. The paper argues that not just labour’s agency, but its class power, is often formed and deployed – and sometimes countered – in the details of how the collective interests of workers, on the farm or across a region, and handled.
Addressing Data Latency in GTFS (General Transit Feed Specification) Realtime to Improve Transit Signal Priority
Authors: Zhou Joseph Q. , Jackson Jay , Stravitz Pam , Barlow Gregory J. , Koonce Peter
Published: July 2024

Transit signal priority (TSP) is a strategy that provides preferential treatment at signalized intersections. TSP reallocates green time to reduce the delay of transit vehicles at traffic signals. To be effective, a transit vehicle (bus) must communicate its location to the traffic signal to make the reallocation of time beneficial. In GTFS (General Transit Feed Specification) Realtime, latency poses a significant challenge for the implementation of GTFS-based TSP. Using data from four transit agencies, this research identifies issues with current GTFS Realtime feeds and proposes a solution using machine learning algorithms to address latency compensation. Experimental results demonstrate that the performance of two machine learning models surpasses the baseline approach, which relies on hourly means for bus speeds and dwell times. This paper tackles multiple issues related to existing GTFS data, enhancing the practicality and feasibility of GTFS-based adaptive TSP. In contrast to conventional approaches focusing on estimation of bus arrival time, this paper emphasizes estimation of bus location and presents an effective method to compensate for latency and improve estimation of bus location and dwell time.
Research on the Effect of Different Length–Diameter Ratios of the Cylindrical Tank on the Roll Stability of Tank Semi-Trailers
Authors: Sun Wencai , Jiang Wei , Tian Jingjing , Li Weijian , Liu Yuwei
Published: July 2024

To investigate the effect of different length–diameter ratios of cylindrical tanks on the roll stability of tank semi-trailers, this paper uses an equivalent mechanical pendulum model to simulate liquid sloshing in the tank. The equation of motion for the equivalent mechanical pendulum model is derived, and the model is subsequently determined. The parameters are integrated with the Trucksim vehicle dynamics model to establish the roll stability model of the tank semi-trailer based on the dynamic characteristics, and joint simulation analysis is carried out under different working conditions. The results show that as the length–diameter ratio of the tank increases, the roll angle of the vehicle gradually increases, the rollover threshold of the vehicle continuously decreases, and the roll stability of the vehicle decreases. As the length–diameter ratio increases, the shock effect of the liquid also increases. This research will provide assistance in the design and development of tank trucks.
Operational Reliability of Hard Shoulder Running on Freeways
Authors: Geistefeldt Justin
Published: July 2024

Hard shoulder running is an effective measure to increase the capacity of freeways during peak hours. In most applications, particularly in Europe, opening and closing the hard shoulder for travel is dynamically controlled depending on the prevailing traffic conditions. By using the hard shoulder as an additional travel lane, the mean capacity of a freeway carriageway is significantly increased, resulting in less congestion and shorter travel times. However, operational reliability might be affected by incidents during which the hard shoulder is blocked and therefore not available for travel, leading to higher variance in the capacity distribution. In this study, the operational reliability of freeway segments with dynamic hard shoulder running in Germany was analyzed based on operating protocols and detector data. By comparing the capacity distributions estimated with and without traffic breakdowns following a closure of the hard shoulder during peak hours, it was found that incidents blocking the hard shoulder, although occurring quite often, had only a minor impact on capacity variability.
From Outsider to Insider: Women's Marital Names and Family Identity in Nineteenth-Century Taiwan
Authors: Yi Jo-lan
Published: July 2024

This article explores the naming customs of married women in Taiwan during the nineteenth century. By attempting to unveil the factors that caused women to prefix the husband's surname, it shows that the practice likely developed from legal and property documents. It also elaborates the convention's relationship with women's family identity, arguing that women were “dual outsiders” in both the natal and affinal family. However, this study finally demonstrates that prefixing the husband's surname did not connote their passivity or subjugation as married women, especially widows who could rely on it to call upon their rights within the family and society.
Incentives and Disincentives in Public Participation – A Review of Public Participation in Planning Practices in China
Authors: Tan Xunran , Kyttä Marketta
Published: July 2024

Public participation is an increasingly popular topic in China, but more attention needs to be given to stakeholders’ willingness to participate. This paper reviews case studies to identify incentives and disincentives for the public and local governments to be involved in public participation in planning. The identified incentives and disincentives are classified into individual, social, civil society, and governmental levels. The study finds that personal interests primarily incentivise the public, while local governments lack essential incentives. Governmental-level factors influence both parties, emphasising the need for political approaches to enhance public participation in planning practices in China.
Exploration of Black/African American College Survivors of IPV During COVID-19 Utilizing Descriptive Analysis
Authors: Parker Brean’a M. , Campbell Erica , Leite Jake , Stansbury Kim
Published: July 2024

The last few decades have ushered in an increase in scholarship focused on campus-based violence, specifically sexual violence, sexual assault, and unwanted sexual experiences. This rise in sexual violence scholarship has promoted the examination of current campus-based interventions, resources, and response systems. However, there exists a dearth of research exploring the experience of intimate partner violence for college students within college/university settings. In this descriptive analysis, we capture the prevalence of intimate partner violence for a nationwide sample of 1,035 college students across diverse college and university campuses within the United States. Researchers utilized a sociodemographic questionnaire and the Intimate Partner Violence Screening Questionnaire to capture and measure college students’ experiences of intimate partner violence during the COVID-19 pandemic. To analyze the data, the Statistical Package for Social Sciences (SPSS 28) was used. Univariate analyses and cross-tabulation analyses were conducted to examine the data. Specifically, due to the majority of research focusing on cisgender, White heterosexual women respondents, we focus our analysis on the experiences of Black and/or African American survivors of intimate partner violence on college campuses, in hopes of capturing the prevalence of intimate and relationship violence for Black/African American college students across colleges and universities. Results of this study revealed the prevalence of all types of intimate partner violence and abuse such as emotional/psychological, physical, and sexual violence within Black/African American college students. Findings from this database study produce implications for college/university campuses to consider capacity to address enduring psychological concerns and outcomes tied to intimate partner violence within college/university campuses, while also considering culturally responsive prevention and intervention efforts.
Antecedents and Consequences of Violence in Homeless Shelters: Perspectives and Experiences of Service Users and Shelter Staff
Authors: Kerman Nick , Kidd Sean A. , Voronov Joseph , de Pass Timothy , Marshall Carrie Anne , Stergiopoulos Vicky
Published: July 2024

Violence is a critical issue in homeless shelters that affects service users and staff, yet there is limited evidence on how shelter-based violence occurs. The objective of this qualitative study was to investigate the antecedents and consequences of shelter-based violence from the perspectives of service users and staff. Purposive sampling was used to recruit individuals experiencing homelessness and shelter staff in a large metropolitan city in Ontario, Canada. Data from in-depth interviews with 56 individuals experiencing homelessness and 30 shelter staff were analyzed. Findings showed that shelter-based violence toward service users and staff was perceived to manifest in response to three interacting factors: (a) burden of homelessness and shelter living, (b) individual histories and marginalization, and (c) interpersonal conflict. These antecedents had a hierarchical structure in that each subsequent factor exacerbated the risk of previous ones and culminated with the most proximal factor for violence. There were three primary outcomes of shelter-based violence reported by service users and staff: (a) health and environmental harms, (b), procedural enforcement, and (c) avoidant behaviors. Avoidance was often a subsequent impact following health harms, as was procedural enforcement to a lesser extent. Overall, the study findings demonstrate that shelter-based violence is a complex and dynamic problem that is perceived to be the result of interacting structural, environmental, programmatic, interpersonal, and individual factors, with similar consequences for service users and staff. Implications for preventing violence through shelter design and service delivery are discussed.
Overextension and Globalization: The Dynamics of Hegemonic Decline
Authors: Bello Walden
Published: July 2024

The global order is undergoing a crisis of hegemonic decline that has two dimensions that are distinct but deeply related. One is a crisis of the American empire that could best be characterized as one of ‘overextension’. This is principally a military and political crisis, which has mainly unfolded in the Middle East. The other ongoing crisis is that of US economic decline brought about by the dynamics of global capitalism, the main aspects of which are globalization, the rapid rise of China, deindustrialization, and financialization of the US economy. These trends have had domestic political and ideological ramifications for US hegemony. Considering the question of hegemonic transition in light of these developments, the article comes to the conclusion that what might be emerging could be not a hegemonic transition, but a condition of hegemonic stalemate between China and the United States because the United States has been countering China’s economic dynamism and global influence with its absolute military superiority.
A visa for a revolution? A theory of anti-authoritarian immigration policy
Authors: Horz Carlo M. , Lee Jonghoon
Published: July 2024

Sometimes, countries target immigration policies to citizens of authoritarian regimes with the goal of influencing these regimes’ politics. Which kinds of immigration rules are optimal anti-authoritarian policies and which trade-offs do policy-makers face? We analyze a game-theoretic model in which a destination country, an autocrat, and a citizen interact. The citizen can engage in protest and emigrate while the autocrat can redistribute and repress to counter these threats. A revolution occurs if the autocrat does not repress and the citizen protests. Policy-makers in destination countries anticipate that in equilibrium, a more permissive immigration policy reduces repression but also reduces protesting. Therefore, the optimal policy strikes a balance between these two effects. A concern for improving the citizen’s welfare renders policy more permissible while the desire to punish the autocrat has an ambiguous effect. Finally, we show that a revolution and large-scale emigration are difficult to achieve at the same time.
Effects of bolt preload relaxation on the mechanical performance of composite structures
Authors: Qi Zhenchao , Zhong Tao , Yang Jie , Yu Fuzhen , Yao Chenxi
Published: July 2024

The durability of bolted composite joints has long been a significant concern within the field. However, the specific influence of transverse vibration relaxation on bolted composite joints has not been extensively studied. This study aims to investigate the effects of transverse vibration relaxation on bolted composite joints. A series of transverse vibration experiments were conducted to investigate the effect of initial preload, displacement load, and lubrication position on bolt preload relaxation. Additionally, tensile tests were performed on composite joints after relaxation and without relaxation to evaluate mechanical properties quantitatively. A finite element model was established to reveal the mechanism of damage evolution. The results indicate that displacement load and thread lubrication have the most significant influence on bolt preload relaxation. The clamping force of the composite structure generated by the smaller preload force has a limited effect on damage suppression during the tensile process. The relaxation of bolt preload can be effectively reduced by increasing the initial preload properly. The tensile strength of composite laminated structures with 10%, 22%, and 32% relaxation (10.4 kN initial preload) decreased by 5%, 6%, and 11%, respectively. Transverse vibration relaxation affects the tensile strength of composite structures, which is caused by the decay of preload. In contrast, the damage to the hole wall of the connection domain caused by transverse vibration almost does not affect the bearing capacity of the composite joints. Overall, this research contributes to the understanding of bolted composite joints’ durability by uncovering the novel effects of transverse vibration relaxation and providing valuable insights for design and optimization strategies in composite joint applications.
Adaptive sliding mode anti-swing control of 4-DOF tower crane based on a nonlinear disturbance observer
Authors: Zhao Chen , He Qin , Zhang Jibin , Zhu Xiangshuai , Meng Qinglin
Published: July 2024

Tower cranes are widely applied in outdoor environments with inevitable external disturbances, which can reduce transportation efficiency and safety. To improve the transient control performance of the tower crane when transporting goods and to guarantee good robustness, this paper designs an adaptive sliding mode Anti-swing control method based on a nonlinear disturbance observer. Firstly, a 4-DOF tower crane error dynamics model considering external disturbances and air friction is established, and then, a nonlinear disturbance observer is designed to estimate the aggregate disturbance. Further, a disturbance effect indicator (DEI) is set to judge the advantages and disadvantages of the disturbance effect on the tower crane system from a new perspective. Finally, beneficial disturbance effects are organically combined with a sliding mode control method possessing an adaptive mechanism to eliminate payload swing by introducing favorable interference. Using Lyapunov stability analysis in conjunction with the LaSalle invariance principle, the closed-loop system is shown to be asymptotically stable. Simulation results show that the controller proposed in this paper achieves accurate positioning by driving the trolley and the jib, and at the same time, can keep the payload swing angle slight during the working process and eliminate the payload swing angle after accurate positioning. Moreover, it is also robust in the face of external disturbances and system parameter variations.
Process-informed simulation of Big-Area Additive Manufacturing (BAAM) of polymers
Authors: Bock Christopher , Ellis Brett D , Rais-Rohani Masoud
Published: July 2024

Process-induced deviation from the intended geometry is a challenge in additive manufacturing, particularly with increasing part size. To address this problem, a modeling workflow was created for polymer-extrusion Big Area Additive Manufacturing (BAAM) using sequentially-coupled thermal and mechanical finite element simulations with focus on stress state and component deformation. Thermal simulations oriented and placed material via an Abaqus/Standard user subroutine and accounted for conductive, convective, and radiative heat transfer to calculate thermal evolution. Mechanical simulations utilized the calculated thermal evolution to calculate thermally-induced stresses and deformations. Simulations were validated via experimental thermal and geometric data from a 3319.1 mm × 235.0 mm × 1016.0 mm corrugated wall printed from carbon fiber reinforced PETg (cfrPETg). Simulated and experimental temperatures were within [Formula: see text] K; simulated and experimental deformations of the lower surface were within 5% (i.e. 2.74 and 2.62 mm, respectively) after accounting for a 0.20-mm ridge attributable to an experimental build plate discontinuity. Lastly, a first-order sensitivity analysis examined the influence of different material properties on warpage and residual stress. For the factors and levels considered, coefficient of thermal expansion (CTE) had the greatest influence on warpage, thus identifying the characterization and tailoring of CTEs as important research topics.
Applying a momentum-based variable formulation in the SIMPLE algorithm to numerically solve thermo-buoyant turbulent flow in enclosures
Authors: Rahimi Farshad , Rashtchian Davood , Darbandi Masoud
Published: July 2024

Natural or buoyant convection flow is an exemplary heat transfer phenomenon, with growing applications in various industries. This article develops a new algorithm, which models and solves the buoyancy-driven turbulent flows in enclosures more accurately than the past similar solvers. A careful literature review shows that the past existing approaches have mostly had serious limitations to apply their algorithms to buoyancy-driven flows with high temperature differences magnitude because of employing the classical Boussinesq approximation. As the novelty of this study, it benefits from a momentum-based variable approach in the context of the semi-implicit method for the pressure linked equations (SIMPLE) algorithm, which lets it accurately solve the strong compressible buoyant flows with high temperature differences. The algorithm is applied to both the Navier-Stokes and the accompanied turbulent flow governing equations using OpenFOAM 4.1 as the platform. To validate the developed algorithm, the current results are compared with experimental data in both square and tall cavities considering low (8.6 × 105), high (1.43 × 106), and very high (1.58 × 109) Rayleigh numbers. As the major contribution of this work, it improves the accuracy of the thermo-buoyant turbulent flow prediction at both low and high Rayleigh numbers. All test cases are carried out employing two different turbulence models of k-ω and k-ε. Furthermore, comparing the results of the present non-Boussinesq algorithm and those of the past developed methods with the experimental data, it is shown that the present algorithm provides a more accurate prediction for the temperature field, that is, <10% differences with the experimental data. Moreover, the present maximum velocity results surpass the solution of the past numerical methods and show <3% differences with the experimental data.
Adaptive endocrine PID control for active suspension based on reinforcement learning
Authors: Li Nan , Shi Yan
Published: July 2024

Recent research has focused on active suspension systems because of their real-time ability to adapt to a variety of road surfaces, external perturbations, and potential to control the smoothness of vehicles. Since the parameters of conventional PID controllers used for active suspension control have limitations due to their inability to adapt to external changes, the fuzzy PID controllers are developed to overcome such limitations. However, fuzzy control have certain disadvantages related to the manual definition of fuzzy rules and variables. In this paper, a first step in improving the robustness of the PID control is to use the endocrine framework, which is considered to be highly nonlinear and complex in the vehicle suspension system. A deep reinforcement learning algorithm is then used to train the intelligence to provide an efficient strategy for adaptive gain adjustment for the endocrine PID, which requires no prior knowledge of active suspension control. The dynamics of the whole vehicle are modeled using ADAMS to analyze the dynamic characteristics of the vehicle at different speeds and road surfaces. The results show that the active suspension based on deep reinforcement learning controlling reduces vertical acceleration of the body more effectively and improves ride comfort more efficiently without sacrificing dynamic suspension deflection or dynamic tire load as compared with passive suspension or fuzzy PID suspensions. Further, the controller performs well under conditions such as changing road grades and vehicle speeds, indicating a good generalization.
Research on coupled bifurcation and stability of tractor semi-trailer under combined braking and steering conditions
Authors: Zhao Jinhai , Wu Xiuheng , Song Zhenghe , Sun Liang , Wang Xiangyu
Published: July 2024

Existing stability analyzes for the tractor semi-trailer cannot fully explain the instability phenomenon during combined steering and braking conditions, under which the tire lateral forces are affected by the longitudinal tire forces due to adhesive force ellipse. In response to the problem, this article obtains the coupled bifurcation and the stability area of the tractor semi-trailer under different deceleration and steering angles. First, the 8 degrees of freedom (8 DOF) tractor semi-trailer nonlinear dynamical model considering the nonlinear tire characteristics is built. The constrained continuation method is used, and the inertial force caused by braking is equivalent to two external forces and added to the tractor semi-trailer model. Thus, the tractor semi-trailer system can be seen as being in an equivalent equilibrium state. Next, the equilibrium points under varying steering angles and different decelerations are solved by a hybrid method combining the Runge-Kutta method with the gradient descent method. The bifurcation diagrams denote the changes in the equilibrium brought by different conditions and reveal the influence of different decelerations on the stable steering angle range. Further, the stable regions under different conditions are illustrated to give an understanding of the effect of the braking operations on the stability of the tractor semi-trailer. Compared with the existing literature, it can be proved that in addition to the fixed parameters such as road adhesion coefficient, the deceleration under braking conditions will also have an impact on the stability regions of the tractor semi-trailer. The stable boundary of the tractor semi-trailer under combined braking and steering conditions can be obtained by off-line calculation, and the results can serve on the theoretical considerations on the tractor semi-trailer braking stability control.
Strengthened elitist genetic algorithm for aeroengine blade arrangement optimisation
Authors: Wei Wuguo , Wu Chao , Zhang Junjie
Published: July 2024

Variations in mass moment of aeroengine blades can cause different residual unbalances, leading to exceeding vibration limit values. For this reason, an accurate and rapid selection of a suitable blade arrangement is essential for improving assembly quality and efficiency. This work innovatively applies the strengthened elitist genetic algorithm (SEGA) to the optimization of blade arrangement for aeroengine. This work investigates the effects of population size (Ps: 100–500), population crossover probability (Pc: 0.6–0.9), and population mutation probability (Pm: 0.6–0.9) on the convergence speed and accuracy of the algorithm, respectively. The obtained results indicate that the optimal parameters of the algorithm are 300 for Ps, 0.7 for Pc, and 0.9 for Pm, which can quickly search for high-precision solution. Compared to the elitist genetic algorithm (EGA), the accuracy value of SEGA is improved about 82%. In addition, this work conducted simulated vibration platform to verify SEGA, and the obtained results show that the vibration values are reduced by 4.19%, 10.19%, and 2.99% at stable speeds of 1000, 1500, and 2000 rpm, respectively, compared to that of group sorting. This work employs a novel SEGA that can effectively improve the accuracy value and reduce vibration values compared to EGA and group sorting, respectively. The above may reduce the residual unbalances of the aeroengine, improve the quality of assembly, and provide a new idea for the assembly of blades.
An inclusive comparative study on the influences of the ring rolling process at elevated temperatures on the mechanical properties and microstructures of two centrifugally cast light alloys
Authors: M-Rahmani Danesh , Fereshteh-Saniee Faramarz
Published: July 2024

High-performance seamless rings made from different alloys have widely been used in various applications. This study compares the effects of the radial–axial ring rolling (RARR) process at elevated temperatures on the mechanical properties of centrifugally cast Al6063 aluminum and AM60 magnesium rings. The cast rings of these two alloys were ring rolled at three temperatures of 200, 250, and 300 °C and three roll rotational speeds of 40, 60, and 80 rpm. The yield stress, ultimate strength and fracture strain of the cast and rolled Al and Mg rings were measured for different directions, namely, rolling direction (RD), transverse direction (TD), and normal direction (ND), as determined by their hardness and the average grain size (AGS). The grain sizes of both the materials after the RARR process were smaller than the cent-cast ones. Moreover, the higher the temperature and/or the main roll rotational speed, the greater the AGS and the lower the yield stress, ultimate strength and hardness of the finally rolled ring. Nevertheless, the AGS of the AM60 samples was much larger than the related Al6063 rings in all the experiments. The ultimate strength, fracture strain and toughness of the Al rolled rings were also larger than the similarly deformed Mg samples, although the specific strength of the latter was much superior to the former. The deformed Mg rings characterized a more isotropic behavior compared to the Al specimens. The effects of the process temperature on the strain-hardening behaviors of these two alloys were also dissimilar. The numerical simulations of the RARR process also illustrated that the maximum, moderate, and minimum equivalent strains in the radial direction were created at the outer, inner, and middle regions, respectively, of the deformed ring, which is in agreement with the experimental findings for the AGSes at these areas.
How does consumer awareness of the waste of electrical and electronic equipment affect reverse logistics? Extended triple bottom line approach
Authors: Choi Hyeseung , Kim Tongkyu , Son Hyeonyu , Kim Donghyun Ken , Park Keunsik , Roh Taewoo
Published: July 2024

This study explores how government support and consumer awareness affect the waste of electrical and electronic equipment reverse logistics in the circular economy framework. To improve waste of electrical and electronic equipment reverse logistics consumer awareness, the extended triple bottom line concept introduces technology with traditional economic, social, and environmental aspects. The impact of government initiatives on consumer awareness and socioeconomic factors on the intention to reuse the waste of electrical and electronic equipment reverse logistics is examined. Partial least squares structural equation modeling was used to analyze survey data from 330 Chinese participants. The results revealed that government policies significantly influence extended triple bottom line awareness while socioeconomic factors impact waste of electrical and electronic equipment reverse logistics reuse intentions. However, direct government support does not significantly impact the expected service quality of waste of electrical and electronic equipment reverse logistics. These findings improve the literature by identifying relevant factors and boosting waste of electrical and electronic equipment reverse logistics comprehension in a circular economy environment, driving the development of efficient and sustainable waste management strategies.
Epistemic disagreement in psychopathology research and practice: A procedural model
Authors: Ward Tony , Sullivan Jacqueline , Durrant Russil
Published: July 2024

Clinical psychology is characterized by persistent disagreement about fundamental aspects of the discipline ranging from what mental disorders are to what constitutes effective treatment. Attempts to address the problem of epistemic disagreement have been frequently based on establishing the correct answer by fiat without identifying and addressing the sources of the disagreement. We argue that this strategy has not worked very well and the result is frequently ongoing and intractable disagreement, with each side in an argument convinced they are correct. In this paper, we outline an epistemic disagreement procedural model intended to assist researchers and clinicians in the field of clinical psychology to identify, explore, and develop inquiry strategies that capitalize on situations where competing knowledge claims are made. The result is a flexible conceptual framework committed to a defensible epistemic pluralism, fallibilism, and contextualism, across the various research tasks constituting the field of clinical psychology.