bluuebunny/crossref_metadata_2025 huggingface dataset:
Mixed modeling approach for efficient simulation of single-phase PWM inverters
Authors: Bortolotto Mario , Migoni Gustavo
Published: July 2024

This paper proposes a new modeling approach to obtain accurate and fast simulations of pulse width–modulated (PWM) inverters with minimal loss of information. The idea of this methodology combines the use of precise switched models and fast averaged models. Switched models are used during transient evolution, and averaged models on periodic steady-state (PSS) regimen . In this way, the switching behavior of an inverter can be obtained even in the context of a long-term simulation where switched models cannot be used because of the central processing unit (CPU) requirement. The novel modeling strategy implements an algorithm that, based on the evolution of some variables, detects the transient or periodic steady state condition and automatically performs the commutation between both models. Furthermore, the mentioned algorithm also estimates the averaged model parameters when the precise switched model is used. Consequently, it is not necessary to calculate the average parameters to create the model and accurate results are obtained regardless of the operating point. This paper also reports simulation experiments of a single-phase PWM boost inverter model to clarify the idea of the modeling strategy and shows the simulation time and accuracy advantages of the proposed modeling approach. The Modelica language was used to program the novel modeling strategy and build the boost inverter examples.
Multi-domain modeling of environment and ecosystem of virtual off-road scenes for simulating ground vehicle autonomy
Authors: Hudson Christopher R , Wheeler Warren , Goodin Christopher , Carruth Daniel W , Harvel Nicholas , Ferguson Joshua , Gabriel Monroe J , McInnis David P
Published: July 2024

Autonomous ground vehicles (AGVs) operating in off-road terrain are influenced by a variety of factors that are unique to the off-road environment, especially the presence of vegetation. Accurately simulating the performance of AGV requires the creation of off-road virtual worlds that realistically present the characteristics of vegetation to simulations of the tires, chassis, and sensor systems. In this work, we present the development and implementation of a coupled soil moisture and vegetation growth model for generating synthetic off-road terrains for use in AGV simulations. These digital scenes have high geometric fidelity for simulating sensor systems used on AGV like terrestrial lidar. The vegetation model uses stored carbohydrates to predict growth cycles and takes multiple phenomenon into account including soil moisture, weather conditions, and seasonal variations. Results of AGV simulations in synthetic terrains are presented as a demonstration of the models utility.
Fabric defect detection algorithm based on improved YOLOv8
Authors: Chen Chang , Zhou Qihong , Li Shujia , Luo Dong , Tan Gaochao
Published: July 2024

Aiming at the problems of low detection accuracy and high leakage rate in traditional detection algorithms, an improved YOLOv8 algorithm is proposed for automatic detection of fabric defects. A swin transformer block was added to the C2f module in the backbone network, which can transfer information between multiple attention layers in parallel to capture fabric defect information and improve the detection accuracy of small-sized defects. To enhance the model’s performance in detecting defects of various sizes, a bidirectional feature pyramid network (BiFPN) was incorporated into the neck. This allows for the assignment of different weights to defect features in different layers. A convolution block attention module (CBAM) was added to the feature fusion layer, enabling the model to automatically increase the weight of essential features and suppress nonessential features during training to solve the problem of leakage detection of small-sized defects due to occlusion and background confusion. The Wise-IoU (WIoU) loss function replaces the conventional loss function, addressing sample imbalance and directing the model to prioritize average-quality samples. This modification contributes to an overall improvement in the model’s performance. The results of the experiment proved that on the self-constructed fabric defect dataset, the algorithm in this paper achieved an accuracy of 97.7%, recall of 95.1%, and mAP of 96.8%, which are 4.4%, 9.4%, and 5.1% higher than those of the YOLOv8 algorithm, respectively. On the AliCloud Tianchi dataset, the algorithm achieves 52.3%, 49.2%, and 49.8% in terms of accuracy, recall, and mAP, respectively, which is an improvement of 4.4% in terms of accuracy, 2.8% in terms of recall, and 2.7% in terms of mAP compared with the baseline algorithm. The improved YOLOv8 algorithm has a high detection accuracy, low leakage rate, and a detection speed of 107.5 FPS, which aligns with the real-time defect detection speed in the industry.
Travel Stress, Leisure Exploration, and Trip Satisfaction: The Mediating Role of Travel Adjustment
Authors: Ramsey Jase R. , Zhang Ye , Lorenz Melanie P. , Hosany Sameer
Published: July 2024

Integrating Torbiorn’s theory of adjustment and Lazarus’ theory of stress, this study examines the antecedents, consequences, and mitigating factors of international business travel adjustment. Results from two studies, a unique pre (Time 1) and post (Time 2) travel survey conducted before COVID at two airports in North and South America, and data collected post-COVID using an online panel of business travelers illustrate how and why adjustment mediates the travel stress/leisure exploration–trip satisfaction relationship. Our findings guide managers and practitioners to mitigate the negative impact of travel stress by allowing time for leisure exploration while on international business trips. Tourism businesses should continue to explore and design experiences that satisfy the general adjustment needs of the international business travel market.
Book review: Karine E. Peschard. 2022. Seed Activism: Patent Politics and Litigation in the Global South
Authors: Ramanna Anitha
Published: July 2024

Karine E. Peschard. 2022. Seed Activism: Patent Politics and Litigation in the Global South. Cambridge, MA: MIT Press. xxii + 183 pp. Figures, appendices, notes, references, index. $35 (paperback—ISBN: 9780262544641).
‘Mutating Records’—Bureaucratic Knowledge in the Realm of Splintering Digitality
Authors: Hasan Nafis Aziz
Published: July 2024

The digitalisation of the state in India and elsewhere has produced a range of effects and critical responses. Arguably, digital processes intervene in the functioning of paper processes, the lynchpin of bureaucratic states with a colonial legacy. Digitalisation must be understood as the emergence of data and technologies splintered across many different locations and functions of the state rather than as a singular form. This article argues that this splintering digitality generates a perspectival stance on the (re)significance of paper by agents of the state that embody its ‘textual habitus’, namely Village Accountants (VAs). Memorialised as writers, VAs have historically been responsible for recording the ever-changing social. Faced with the computerisation of records and their removal from participation in key inscriptional events, they generate a critique of writing and point to non-textual forms of information that congeal outside written records. In doing so, they provide a view into the encounter between digitalisation and bureaucratic knowledge.
Relationships Between Self-Reported Pain and Optimism Among Community-Dwelling Older Adults
Authors: Rivera Lucía C. , Mancilla Isabel A. , Bergstrom Jaclyn , Thompson Sharon , Molina Anthony J.
Published: July 2024

Measures of life outlook in older adults have been investigated in connection to pain, as both pain management and outlook are important factors of successful aging. We hypothesized that higher pain is associated with lower optimism among community-dwelling older adults. We utilized data from the UC San Diego Successful Aging Evaluation (SAGE), a prospective longitudinal cohort study initiated in 2010, to evaluate the relationship between pain and optimism in 378 community-dwelling adults aged ≥50 years. We used the revised Life Orientation Test (LOT-R) to measure optimism and three pain subscales–PROMIS Pain Interference, PROMIS Pain Intensity, and MOS 36-Item Short-Form Health Survey (SF-36)–as pain measures. Regression analyses reveal negative relationships between pain and optimism for all three pain scales, with regression coefficients of −0.277 ( p < .0001), −0.246 ( p < .0001), and 0.269 ( p < .0001) respectively. This indicates value in considering physical and psychological elements in future intervention research to promote healthy aging.
Refined composite multivariate multiscale weighted permutation entropy and multicluster feature selection-based fault detection of gearbox
Authors: Gong Jiancheng , Han Tao , Yang Xiaoqiang , Chen Zhaoyi , Dong Jiahui
Published: July 2024

As a valuable method for quantifying irregularity and randomness, multivariate multiscale permutation entropy (MMPE) has found widespread application in feature extraction and complexity analysis of synchronized multi-channel data. Nonetheless, MMPE fails to consider the amplitude information of the data, and its coarse-graining process possesses inherent flaws, resulting in inaccuracies in evaluating entropy values. To address these issues, a novel nonlinear dynamic characteristic evaluation index, named refined composite multivariate multiscale weighted permutation entropy (RCMMWPE), has been developed. This index aims to comprehensively rectify the shortcomings of disregarding amplitude characteristics and incomplete coarse-graining analysis in MMPE, thereby preserving crucial information present in the original time series data. Through the analysis and comparison of multi-channel synthetic signals, the efficacy and superiority of RCMMWPE in assessing the complexity of synchronized multi-channel data have been confirmed. Subsequently, an intelligent fault detection framework is introduced, leveraging RCMMWPE, multicluster feature selection (MCFS), and kernel extreme learning machine optimized by the particle swarm optimization algorithm (PSO-KELM). The proposed fault detection scheme is then applied to test gearbox fault data and extensively benchmarked against other fault detection schemes. The results demonstrate that the proposed gearbox fault detection scheme excels in accurately and consistently identifying fault categories, outperforming the comparison schemes.
Ownership, Control, and Productivity: Family Firms in Comparative Perspective
Authors: Aguilera Ruth V. , Crespi-Cladera Rafel , Martín-Oliver Alfredo , Pascual-Fuster Bartolomé
Published: July 2024

While the property right theory has gained prominence in contemporary literature, there is a notable lack of empirical research into its relevance. This study delves into the implications of the property right theory concerning family-owned businesses and their impact on productivity. Specifically, we explore how family firms’ characteristics affect the benefits and hazards derived from the rights to utilize, appropriate, and transfer firm resources, influencing the production process and, more specifically, the levels and growth of a firm’s productivity. Based on an extensive dataset of European firms, our findings indicate that family-owned businesses tend to prioritize labor over capital in their production processes when compared with nonfamily firms. Moreover, the distinctive decisions regarding the production process lead to consistently lower levels of productivity in family firms. However, we also uncover that when family firms share with non–family members management and ownership control, they are less labor intensive and achieve higher productivity and productivity growth. This suggests that certain ownership and control structures can help family firms overcome the productivity gap with nonfamily firms. Overall, our findings support the ideas from recent developments in property rights theory, considering the unique characteristics of family-owned businesses. Our study contributes to strategy research on family firms and corporate governance.
Funding Innovation and Risk: A Grey-Based Startup Investment Decision
Authors: Srivastava Manoj Kumar , Dash Ashutosh , Shaikh Imlak
Published: July 2024

As found in behavioral decision theory, venture capitalists (VCs) rely on heuristics and bias, owing to their bounded rationality, either by limited alternatives or information and resources. India’s booming startup scene challenges VCs in decision-making owing to information overload from numerous evolving ventures, which hinders informed judgment. VC investment behavior, due diligence, and cognitive factors related to decision-making have always drawn the attention of researchers. We provide an alternative approach for an optimal decision by VCs by identifying the attributes that influence investment or funding decisions at an early stage of a venture in tech-based industries. Through a literature review, we identify eight attributes, both on internal and external criteria, that venture investors consider when making investment decisions. Based on interviews with 20 experts, we further identify eight key tech-based sectors. Using grey system theory, we then determine the rankings of eight tech startups for investors’ early-stage investment decisions. This study presents a linguistic variable-based approach of grey numbers to decide weights and ratings, the grey possibility degree to compare and rank different tech startups, and based on the results, suggests the ideal tech startup. We find that agritech ranks first; thus, investors should prefer venturing into such startups for early-stage investment. E-commerce and edutech ranked second and third, respectively, followed by electric vehicle infrastructure, insurtech, fintech, space tech, and software as a service.
Effects of Mediterranean and Western dietary patterns on perceived stress and mental distress
Authors: Chowdhury Ushima , Bubis Sabrina , Nagorny Katerina , Welch Megan , Rosenberg Lexis , Begdache Lina
Published: July 2024

Compared to the Western diet, the Mediterranean diet has many known benefits for both mental health and physical health; however, little is known about the effect of these dietary patterns on perceived stress and mental distress. To assess the relationship between dietary patterns, perceived stress and mental wellbeing, an anonymous online questionnaire targeting adults 18 and older was distributed via several social media platforms and email listservs. The survey included demographic questions, the Food-Mood Questionnaire, the Perceived Stress Scale and the Kessler Psychological Distress scale (K-6). A total of 1591 participants completed the survey. The data was analyzed using Principal Component Analysis and Pearson Correlation Coefficient in SPSS version 28.0. The results showed significant negative correlations between perceived stress and mental distress with several components of the Mediterranean diet, such as whole grains, seafood, fruits, vegetables, and beans. Despite being attributed to the Western diet, meat produced a negative correlation with perceived stress and mental distress. However, significant positive correlations between perceived stress and mental distress and the Western diet, such as fast food and high glycemic index food, were detected. Our findings provide evidence that dietary patterns modulate the stress response and suggest that incorporating components of the Mediterranean diet is beneficial for mental wellbeing and stress reduction.
The Effect of Talc on Cell Nucleation in Extrusion Foam Processing of Polypropylene with CO2 and Isopentane
Authors: Park Chul B. , Cheung Lewis K. , Seung-Won Song
Published: July 2024

The effect of talc on cell nucleation of polypropylene (PP) foam was investigated. Branched high-melt-strength PP was used to reduce bubble coalescence during extrusion foam processing. When isopentane was used as a blowing agent, bubble nucleation was dominated by the talc concentration, and the isopentane content did not affect the cell density very much. By contrast, when CO2 was used as a blowing agent, both talc and CO2 concentrations determined the cell-population density. However, the effect of talc on nucleation was significant only when the CO2 content was low. In addition, the maximum achievable cell density was not improved by talc when CO2 was used whereas the maximum cell density was dramatically improved by talc when isopentane was used. The experimental results indicate that the heterogeneous bubble nucleation mechanisms in plastic foam processing with CO2 are fundamentally different from those in the processing with a long-chain blowing agent such as isopentane.
Intergenerational transmission of familial relational dysfunction: A test of a complex mediation model based on Bowen family systems theory
Authors: Čepukienė Viktorija , Neophytou Kleanthis
Published: July 2024

Up to date, the systemic mechanisms that explain the intergenerational transmission of familial dysfunction remain theoretically and empirically unclear. Hence, this study examines the intergenerational transmission of relational and intrapersonal dysfunction and their collective effect on the psychological adjustment of third-generation children through the lens of Bowen family systems theory. Lithuanian parents ( N = 348; Mage = 40.66; range 26–59) of children aged six to ten years cross-sectionally reported on their differentiation of self (DoS), emotional and relational dynamics within their family-of-origin and nuclear family, and the psychological adjustment of their child of greatest concern. Structural equation modeling and mediation analyses findings offered empirical support to Bowen theory, highlighting that family-of-origin dysfunction is associated with nuclear family intrapersonal and relational dysfunction, and ultimately with third-generation’s psychological maladjustment. Results demonstrated that a poor family-of-origin emotional system appears to contribute, via triangulation processes, to reduced DoS in adult children. The reduced DoS appears to perpetuate intergenerational triangulation, and to negatively impact couple relationship and co-parenting functioning within the nuclear family. In contrast to triangulation, couple dysfunction was found to predict poorer psychological adjustment in third-generation offspring. This study advances family systems theory by (i) examining the prominent role of triangulation and DoS within the intergenerational transmission process, (ii) highlighting the potential differential impact of a negative nuclear family emotional system on children through triangulation, and (iii) clarifying the potential role of spousal relationship satisfaction and co-parenting in mediating the relationship between parental DoS and offspring’s psychological adjustment.
Controlling intermetallic compounds formation in commercially pure titanium/electrolytic tough pitch copper dissimilar joint
Authors: Rahimi Amir Masoud , Mostafaei Mohammad Ali
Published: July 2024

Welding titanium to copper is challenging due to the differences in their thermophysical properties and the formation of intermetallic compounds (IMCs). This study uses gas tungsten arc welding to join commercially pure titanium sheets to electrolytic tough pitch copper without using filler metal, and electrical currents ranging from 80 to 100 A to achieve completely penetrated joints. Microstructure analysis shows the formation of a columnar structure of IMCs at the weld zone, including Ti2Cu, TiCu, Ti3Cu4, Ti2Cu3, and TiCu3. Tensile and three-point bending tests were carried out to investigate the effects of IMCs formed by welding on the mechanical properties. The maximum tensile strength was achieved for the sample with the thinnest intermetallic layer, while brittle fractures were observed in all samples.
Metallurgical developments in steam-methane reformer tube alloys
Authors: Tse Martin C. H. , Livera Elaine R. , Christofidou Katerina A.
Published: July 2024

Alloy development plays a vital role in the technological advancement in steam-methane reformers, with development remaining stagnant in the past three decades. This critical review aims to provide the overview of previous development strategies and highlight the challenges faced by the future development of reformer alloys. In this review, the physical metallurgy of modern reformer alloys is introduced, demonstrating the significance of the MC, M7C3 and M23C6 carbides commonly observed, and the careful balance between alloying additions and the designed microstructures governing performance. The compositional developments, along with the advancements enabled by the introduction of centrifugal casting, are highlighted. The effects of common alloying additions are also addressed, with implications of the existing knowledge on future alloy development opportunities, discussed.
A dispensable role of mural cell-derived laminin-α5 in intracerebral hemorrhage
Authors: Ruan Jingsong , Kang Minkyung , Nirwane Abhijit , Yao Yao
Published: July 2024

Although most laminin isoforms are neuroprotective in stroke, mural cell-derived laminin-α5 plays a detrimental role in an ischemia-reperfusion model. To determine whether this deleterious effect is an intrinsic feature of mural cell-derived laminin-α5 or unique to ischemic stroke, we performed loss-of-function studies using middle-aged mice with laminin-α5 deficiency in mural cells (α5-PKO) in an intracerebral hemorrhage (ICH) model. Control and α5-PKO mice exhibited comparable changes in all parameters examined, including hematoma size, neuronal death, neurological function, blood-brain barrier integrity, and reactive gliosis. These findings highlight a minimal role of mural cell-derived laminin-α5 in ICH. Together with the detrimental role of mural cell-derived laminin-α5 in ischemic stroke, these negative results in ICH model suggest that mural cell-derived laminin-α5 may exert distinct functions in different diseases.
Pilot Study to Incorporate Network-Level Structural Condition in Agency Pavement Management Practices
Authors: Murekye Angello , Katicha Samer W. , Urbaez Ernesto E. , Flintsch Gerardo W. , Diefenderfer Brian K.
Published: July 2024

The structural condition of roadway pavements is crucial in assessing the overall health of roadway networks and making informed decisions on maintenance and rehabilitation interventions. While current pavement management systems (PMSs) primarily rely on surface distress conditions, incorporating structural condition assessment at the network level can enhance decision-making processes. An approach is presented to incorporate network-level structural condition measurements obtained from the traffic speed deflectometer (TSD) in the Virginia Department of Transportation PMS. This involves determining a structural number, calculated using TSD measurements, selecting an appropriate structural condition measure (remaining structural service life) for use in the PMS, enhancing treatment selection decision trees, and conducting a cost analysis. The TSD-derived effective structural number, obtained following the American Association of State Highways and Transportation Officials (AASHTO) 1993 empirical design procedure, is utilized with traffic projections and other design information to estimate the remaining structural service life. In the treatment recommendation process, surface distress information is combined with the structural condition assessment, considering budget allocation and pavement useful life. For US Route 29 in Virginia, comparing treatment costs revealed a potential 33.2% cost saving for one maintenance cycle using the augmented decision process, which includes structural assessment, compared with surface distress assessment alone. This approach could provide a comprehensive framework for integrating structural condition assessment in PMSs, enabling more effective and cost-efficient decision-making for roadway networks. To further optimize resource allocation and improve accuracy, combining the augmented treatment selection process with deterioration predictions for a cost analysis over several maintenance cycles is recommended.
Applying an Agent-Based Social Network in Travel Forecasting with Effects on Disease Spread
Authors: Ji Joanna Yuhang , Hannon Gabriel Ignatius , Zhang Qin , Moreno Ana Tsui , Moeckel Rolf
Published: July 2024

Travel demand models benefit from integrating social networks to capture socially induced travel behavior, such as destination choice. One of the obstacles to this integration is the lack of reliable and realistic social networks as input. This paper introduces an agent-based method to synthesize social networks with global characteristics and heterogeneous ego-centric homophilies (distance, age, gender) for a substantial population (approximately [Formula: see text] individuals). Drawing on data from an ego-centric snowball sample, it successfully replicates age, gender, and distance homophilies while achieving significant social network-level transitivity and clique structures. The study uses epidemic spread as a case study to explore the effects of incorporating social networks and coordinated destination choices into travel forecasting. Results show that while the total number of infections remains unchanged, the integration of social networks and coordinated destination choices affects contextual aspects of infection events. Coordinated travel through social networks accelerates the initial spread and affects the spatial distribution of epidemics. The findings underscore the importance of integrating social networks and joint travel to more accurately represent social travel behavior.
Incorporation of Cellulose Nanocrystals Synthesized from Rice Husk in Engineered Cementitious Composites
Authors: Gavilanes Andrea , Noorvand Hassan , Hassan Marwa , Arce Gabriel , Rupnow Tyson
Published: July 2024

Engineered cementitious composites (ECCs), belonging to the class of high-performance fiber reinforced cementitious composites, are distinguished by their exceptional tensile strain capacity. However, practicality concerns have prompted the exploration of alternative components in their fabrication, sometimes compromising their mechanical properties. This study investigates the influence of cellulose nanocrystals (CNCs) on the mechanical properties of two types of ECC mixtures: the M-0 mixture, which uses locally sourced materials, and the M-50 mixture, which incorporates sugarcane bagasse ash. CNCs were added to these ECCs in varying concentrations of 0.5, 1.0, 1.5, and 2.0 wt.% of cement, synthesized from rice husk via an acid hydrolysis process. Characterization techniques, such as X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy, and thermogravimetric analysis, were employed to analyze the nanocrystals of CNCs. Compression and tension tests were performed to evaluate the mechanical properties of the M-0 and M-50 mixtures, followed by flexural testing on the mixtures with the most promising tensile properties. TEM analysis indicated that CNCs have an aspect ratio ranging from 7 to 14, while XRD results confirmed a crystallinity index of 55% for CNCs. Notably, CNCs were found to significantly enhance the compressive strength of both the M-0 and M-50 mixtures. Furthermore, the addition of CNCs to the M-50 mixtures resulted in an impressive high strain capacity of 3.24%.
Anticipating Stress During the COVID-19 Pandemic: Mental Health Among Latinx Young Adults
Authors: Villatoro Alice P. , Wagner Kevin M. , Walsdorf Ashley A. , Salgado de Snyder V. Nelly , Garcia Deliana , Valdez Carmen R.
Published: July 2024

We examined the association of anticipatory negative consequences related to the COVID-19 pandemic on the mental health of Latinx young adults. Data are from a community-based study with first- and second-generation immigrant, Latinx young adults (18–26 years old). Participants completed an online survey about mental health and anticipated personal and family-related consequences due to the pandemic. Regression models examined the effects of anticipated consequences on risk of clinically significant mental health symptoms. Latinx young adults anticipated moderate levels of negative consequences during the pandemic, including expected illness, economic strain, and psychosocial concerns. Anticipating psychosocial concerns was associated with serious psychological distress, whereas anticipating economic hardship had a limited effect on somatization and anxiety symptoms. Probability of contracting COVID-19 illness was not associated with mental health symptoms. Addressing the anticipation of negative consequences is important because these consequences threaten mental health and wellbeing. Strategies are needed to alleviate continuing pandemic-related stressors among Latinx communities to promote mental health.
Boundary Work and Strategies of Compliance: The Underlife of the Ivory Tower
Authors: Martin Daniel D. , Wilson Janelle
Published: July 2024

This study examines strategies employed by university administrators and managers to gain compliance from subordinates even as they attempted to increase their workload. These strategies have received comparatively little attention within organizational studies of compliance. The participants in our study included employees at a public university in the Midwest identifying themselves as either “staff/faculty” or “managers/administrators.” Our findings indicate that when administrators and managers are unable to use formal rewards and punishments they attempt to gain compliance from subordinates through two main strategies that we identify as overtures and interactional trebuchet. Both strategies represent a sequence of interaction that we refer to more generally as “boundary work”—a set of activities through which boundaries on time, resources, and workload are defended or diminished, and for which we provide a model. We draw upon organizational, symbolic interactionist, and dramaturgical theories in the analysis of our data.
Numerical and experimental investigation of vibration and response optimization of a car chassis with effect of changing driving speed
Authors: Mosin K Shaikh , Yadao Adik
Published: July 2024

Vibration of automobile vehicles is the important issue in the entire vehicle design process as it affects the comfort level and the overall image of a vehicle, an experimental evaluation and prediction of vibration level of the vehicle in stationary and driving conditions are often necessary. This paper delves in to a numerical and experimental investigation of vibration and response optimization of a car chassis with peak acceleration and peak amplitude level of vibration as a response parameter in vertical motion. These response parameters were obtained numerically by developing a mathematical model of car and equation of motion. Newmark Beta method used to solve the equation of motion to get the values of response parameters in MATLAB software. For the experimental investigation of the response parameters a car with monocoque chassis, three cylinder engine, Macpherson front suspension and twist beam rear suspension with coil spring considered and FFT analyzer used for the data collection of the response parameters, FFT analyzer works on the fast Fourier transform algorithm. Comparative analysis between the numerical and experimental investigated values of response parameters shows the minimum error of 0.6035% and average error of 2.81% at various points on chassis; it shows the precision of the mathematical model and practical car model. To optimize the performance index of response parameters Fractional factorial design of experiment (DOE) method applied with six factors and two levels. The main effect analysis, analysis of contribution, analysis of variance and backward elimination method were applied in fractional factorial design. Regression equation for the response parameters were obtained with two level six factor fractional factorial design for the vibration level prediction. The comparative analysis of the response parameter levels before and after the optimization shows the reduction of 65.61% in peak acceleration level and reduction of 17.70% in the peak amplitude level of a car chassis with respect to change in the driving speed. The design and optimization method proposed in this study has a significant effect on the vibration reduction of the car chassis which provides a reference for the optimization of the vibration level to improve the performance of car suspension.
Exploring the post-heat treatment on the electropolishing characteristics of laser powder bed fusion processed Inconel 718 superalloy
Authors: Shrivastava Abhishek , Anand Kumar S , Rao Samrat
Published: July 2024

The influence of post-heat treatment on the microstructural and electropolishing characteristics of the laser powder bed fusion processed Inconel 718 is studied. The electropolishing results show a significant decrease in the surface roughness for as-printed (∼69%) and post-heat treatment conditions (∼74%) with increasing current density and polishing time. The surface morphology of the as-printed samples showed the presence of unaltered asperities on the electropolished surface, which can be attributed to the precipitation of non-conductive lave phases and metal carbides during laser powder bed fusion processing. The post-heat treatment homogenizes microstructure and dissolves these phases in the metal matrix along with the precipitation of strengthening phases. As a result, the surface morphology of post-heat treatment samples becomes more uniform, signifying fewer surface irregularities. The statistical parameters show a significant reduction in sharp asperities in the post-heat treatment condition. The material ratio curves revealed uniform material distribution in the post-heat treatment samples, signifying reduced surface asperities compared to as-printed conditions.
Finite element method-enabled machine learning for analysing residual stress and plastic deformation in surface mechanical attrition-treated alloys
Authors: Sayed Biju Theruvil , Sari Arif , Ghribi Wade , Alkurdi Ahmed AH , Askar Shavan , Mohmmed Karrar Hatif
Published: July 2024

This paper presents a novel machine learning model designed to predict residual stress and equivalent plastic deformation in metallic alloys undergoing surface mechanical attrition treatment. The dataset used for training was generated by numerically simulating surface mechanical attrition treatment on various alloys, such as SS316L, NiTi, Ti64, Al7075, and AZ31. The regression analysis of the proposed model exhibits exceptional predictive capabilities, with high R² values of 0.959 for residual stress and 0.911 for average equivalent plastic strain, alongside low root mean square error values of 0.035 and 0.088, respectively. Furthermore, the detailed examination of the correlation between input features and output targets revealed that the increase in values of residual stress and plastic strain in treated samples corresponded with heightened weight functions of processing parameters and material properties, respectively, within the machine learning model. A case study focusing on Al7075 was also provided, demonstrating the model's ability to adjust parameters effectively to achieve specific surface residual stress and plastic strain outcomes. Ultimately, the proposed model not only serves as a reliable predictor for the output targets but also functions as a valuable tool for characterizing the complex input–output relationships, thereby reducing the need for trial and error experimentation in real-world scenarios.
Observer-based adaptive fuzzy control of stabilized platform in rotary steerable system with input saturation and output constraint
Authors: Wan Min , Song Jiaru , Wang Guorong
Published: July 2024

This paper explores the control strategy for toolface tracking in the stabilized platform of a rotary steerable system, considering both input saturation and output constraint. To mitigate the impact of unknown friction torque and modeling error on the stabilized platform, we propose an adaptive fuzzy backstepping control approach. A fuzzy state observer is specifically devised to handle the uncertain state arising from unknown friction torque and modeling errors. Introducing an auxiliary system effectively compensates for input saturation, and the resolution of the output error constraint is achieved through the construction of a barrier Lyapunov function. Furthermore, employing the Lyapunov method establishes that all signals in the entire closed-loop control system are semi-globally uniformly ultimately bounded. Simulation results confirm the efficacy of the proposed control methodology.
The 1942 Garmisch Conference: A Snapshot of Mid-War Axis Naval Strategy
Authors: Hayward Joel , Fiore Massimiliano
Published: July 2024

On 14 and 15 January 1942, a German and Italian maritime strategy conference occurred in Garmisch-Partenkirchen in order to coordinate a joint plan of action for the ongoing conduct of naval warfare. Drawing upon extensive exploration in German and Italian archives, this article challenges coventional wisdom and argues that coordination improved as a consequence of the meeting and that strategic realities, not a lack of intent to coordinate the two nations’ naval efforts, robbed the conference of its ability to create war-changing decisions.
Book review: Suranjan Das and Anita Sengupta (Eds.), Contiguity, Connectivity and Access: The Importance of the Bay of Bengal Region in Indian Foreign Policy
Authors: Bhat Waseem Ahmad , Majid Shazia
Published: July 2024

Suranjan Das and Anita Sengupta (Eds.), Contiguity, Connectivity and Access: The Importance of the Bay of Bengal Region in Indian Foreign Policy (Routledge, 2022), 214 pp. $54.99, ISBN: 978-10-0336-502-0 (ebk).
Pedagogical Dimensions and Intercultural Learning Outcomes of COIL: A Review of Studies Published Between 2013–2022
Authors: Fukkink Ruben , Helms Rochelle , Spee Odette , Mongelos Arantza , Bratland Kari , Pedersen Rikke
Published: July 2024

This systematic review examines pedagogical barriers and facilitators for intercultural learning in Collaborative Online International Learning (COIL)/International Virtual Exchange (VE) projects, as well as their related outcomes. The review analyzed 56 studies published between 2010–2022 in the databases ERIC, PsychInfo, Scopus, and Web of Science. Following the TPACK model as an analytical framework, findings suggest that COILs can have a positive impact on intercultural learning when different barriers and facilitators related to pedagogical knowledge, pedagogical content knowledge, and technological pedagogical knowledge are effectively addressed throughout the preparation, execution, and evaluation stages of COILs. Overall, the majority of outcomes for intercultural learning were positive (61.8%), but also zero results (23.6%) and negative findings (14.5%) have been reported for the affective, behavioral, and cognitive domain. The review offers pedagogical recommendations for intercultural learning with COILs, along with a discussion of strengths and limitations of the current knowledge base.
Examining International Graduate Students’ Career Willingness in China: Influencing Factors and Integration of Professional Development
Authors: Jeremie Maguatcher , Maimaiti Gulinuer , Ru Ning
Published: July 2024

China has become an increasingly popular destination for international students pursuing graduate education. This research examines the factors influencing international graduate students’ willingness to work in China, focusing on motivational aspects, employment considerations, and the challenges faced in the Chinese job market. The study employs a combination of push-pull and acculturation theories to interpret the data collected through surveys and interviews. The key findings reveal that students are drawn to China for their studies due to the high-quality education, available scholarships, opportunities for professional development, and cultural exchange. Many expressed interest in remaining in China for employment due to attractive salaries and favorable job prospects. However, they face significant challenges, such as language barriers, cultural differences, unfamiliarity with the local job market, strict visa policies, and a highly competitive employment environment. The study emphasizes the need to enhance the visibility of job opportunities, bridge language and cultural gaps, enhance workplace diversity and inclusivity, strengthen international networks and alumni associations, and encourage entrepreneurship among these graduates. These measures aim to help students navigate the job market and enrich China's workforce with diverse skills and perspectives, further establishing China as a leading global education and professional development hub.
Vibration analysis of a partially covered beam with a shear thickening fluid core
Authors: Li Weijun , Lin Kun , Wang Kaifa , Wang Baolin
Published: July 2024

The vibration responses of a sandwich beam with partially covered by shear thickening fluid (STF) layer under an impact load are investigated. The nonlinear governing equations of the flexural vibration are derived based on extended Hamilton’s principle and are solved by the finite difference method. The model is then validated and used to develop a complete parametric study of partially covered beams with the STF-filled core to properly design and place the STF patch. It is found that, for the first vibration mode, maximum damping, and the smallest change in the natural frequency are achieved when the coverage length of the partial STF patch exceeds 50% and the center of the patch is positioned at 56.25% from the left edge. For the second vibration mode, the coverage length is 37.5% and the center of the patch is located at 75% from the left edge of the beam. Additionally, it has been observed that maintaining a thickness ratio of 0.75 between the constraining layer and the base beam leads to increased damping, while simultaneously minimizing alterations in the natural frequency of the original beam. The results can be used for the structural design of sandwich beams partially covered by STF.
“A National Review of Crowdfunding for Plagiocephaly Helmets”
Authors: Podszus B. , Pham J. , Dopson E. , Trivedi S. , Yu V. , Guo Y.
Published: July 2024

Objective

Custom prescription helmets for plagiocephaly may be a significant financial burden for families, especially when not covered by insurance. This study aims to identify factors that influence the success of crowdsourcing campaigns for this therapy.

Design

GoFundMe campaigns were collected by searching terms such as “plagiocephaly” and “baby helmet.” Two reviewers analyzed each campaign for variables, including demographic data, story elements, and photo characteristics. Univariate logistic regression was used to determine each variable's impact on success, defined as attaining ≥75% of a campaign goal and significance of p ≤ 0.05.

Results

Campaign data from 2011 to 2022 were analyzed. Initial search yielded 1464 campaigns; among these 413 met final inclusion criteria. On average, campaigns raised $2005 (range: $0-$7799) and requested $3151 (range: $160-$30,000). In total, 228 (54%) achieved success, 167 (40%) met their goal, and 35 (8%) raised no funds. A total of $828,256 was raised from the requested $1,301,317. The average reported age was six months (range: 2–17 m). Significant factors associated with success were military affiliation, providing multiple images, including a quoted cost, providing campaign updates, indicating a sense of urgency, diagnosis of torticollis, and mentioning possible complications without treatment. Raising additional funds for therapy, multiple helmets, and unrelated medical costs negatively impacted success. Racial disparities were observed between campaigns. Additionally, regional differences were noted between campaigns.

Conclusions

Crowdsourcing can be a successful endeavor for some families experiencing financial hardships from helmet therapy. This study highlights current gaps within healthcare coverage for helmet treatment and identifies various factors influencing crowdfunding campaigns.
The Role of State and National Institutional Evaluations in Fostering Collective Accountability Across the U.S. States
Authors: Algara Carlos , Specht Alexander
Published: July 2024

Theories of collective accountability in American elections center on the ability, and willingness, of voters to hold legislators accountable for the job performance of the president and his party in Congress. While this work finds that legislators pay an electoral penalty for low institutional approval ratings under their party’s control, little is known whether this form of collective accountability translates to the state legislative context. We argue that collective accountability in state legislative elections follows a two-tiered approach, with state legislators being held accountable for national and state policymaking institutions. Using new state-level measures of institutional approval for national and state institutions, along with voter-level data from the 2007–2020 Cooperative Election Study, we find that presidential approval is the principal growing motivator of state legislative partisan choice with other policymaking institutions playing a minimal role, at best. These findings suggest that the electoral fortune of state legislative candidates, and state parties, are largely and increasingly determined by national forces outside of the purview of state-level policymaking institutions.
Assessing Safety of Anticoagulation for Atrial Fibrillation in Patients with Cirrhosis: A Real-World Outcomes Study
Authors: Song Justin J. , Jackson Nicholas J. , Shang Helen , Honda Henry M. , Boulier Kristin
Published: July 2024

Aims

In patients with atrial fibrillation (AF) and stroke risk factors, randomized trials have demonstrated that anticoagulation decreases the risk of ischemic stroke. However, all trials to date have excluded patients with significant liver disease, leaving guidelines to extrapolate recommendations. We aim to evaluate the impact of anticoagulation on safety events in patients with AF and cirrhosis.

Methods and Results

In this retrospective cohort study, we obtained de-identified health record data to extract anticoagulation strategy, comorbidities, prescriptions, lab values, and procedures for a cohort of patients with cirrhosis who develop AF. After selecting a propensity matched population to match patients with various anticoagulation strategies, we tracked data on outcomes for death, transfusion requirements, hospital and ICU admissions. After propensity score weighting and multivariable adjustment, anticoagulation strategy was associated with increased hospital admission count (OR = 1.74 per admission, P < .001), binary risk of hospital admission (OR = 1.54, P = .010) and risk of ICU admission (OR = 1.41, P = .047). We detected no significant differences in mortality, transfusion of blood products, or average length of stay. Direct oral anticoagulant (DOAC) prescriptions were associated with increased binary risk of hospital admission compared to warfarin prescriptions. In a third comparison, DOAC strategy alone was associated with increased hospital admission count (OR = 1.41 per admission, P < .001) and binary risk of hospital admission (OR = 1.52, P = .038) compared to no anticoagulation strategy.

Conclusion

Anticoagulation strategy in patients with cirrhosis and AF was associated with increased rate of hospital admission and ICU admission but not associated with increased risk of mortality or transfusion requirement.