bluuebunny/crossref_metadata_2025 huggingface dataset:
Validity and reliability of Spanish version of the EQ-i: YV[S] in Colombian children and youth
Authors: Navarro Roldán Claudia Patricia , Mateus Gómez Sandra , Botero Ruge María Catalina , Velez Gabriel
Published: August 2024

Validity and reliability evaluations of the Emotional Quotient Inventory: Youth Version (EQ-i: YV[S]) with children and adolescents fromdifferent countries have shown variations in the structural model proposed by Bar-On. Objective. To examine the psychometric properties of EQ-i:YV[S] with a Colombian’ sample. Method. We randomly selected a sample of 1355 children and adolescents between 8 and 14 years old (Mage = 10.80;SD = 1.41). We conducted exploratory (n1 = 416) and confirmatory (n2 = 939) factor analyses (EFA, CFA), reliability, internal consistency, and predictive validity. Results. The EFA explained 27.6% of the variance. The AFC indicated a multidimensional structure with four factors and 21 items obtained the best fit (χ 2 = 334.358; df = 183; RMSEA=0.030; CFI=.951;TLI=944; NFI=.899) with acceptable internal consistency (ω = .57,.75). EQ-i: YV[S] factors explain 18.5% of the observed variance in problem-centered coping scores. Conclusions. The psychometric fit of the inventory supports evidence of its usefulness for screening processes in clinical or educational assessment.
ESTUDO COMPUTACIONAL DA INFLUÊNCIA DE CO2 NO EMPILHAMENTO-π DE MONÔMEROS DE CORONENO SUBSTITUÍDOS COM ENXOFRE
Authors: F. P. Laeber Kelly , M. Prates Leticia , Baptista Leonardo , T. M. Cruz Maurício
Published: August 2024

COMPUTATIONAL STUDY OF THE INFLUENCE OF CO2 ON THE π-STACKING OF SULFUR-SUBSTITUTED CORONENE MONOMERS. Asphaltenes are complex molecules with a tendency to aggregate. This property can be an issue for the oil industry due to CO2 reinjection into reservoirs to mitigate these gas emissions. The present theoretical study aimed to study the CO2 interaction with no-substitute and substituted coronene as an asphaltene model compound at CAM-B3LYP-D3/6-311G(d,p) level. The electronic properties were evaluated using harmonic oscillator model of aromaticity (HOMA), quantum theory of atoms in molecules (QTAIM), and reduced density gradient (RDG) methods. The results showed that the coronene’s functionalization by a sulfur atom changes the coronene’s electronic structure. However, functionalization does not change the type of interactions between the monomers, as they remain predominantly van der Waals interactions. CO2 interaction with substituted coronene barely changed due to the presence of sulfur atoms. However, in dimers, the position of the heteroatom directly influences the interaction with CO2, although it is insufficient to change the interaction’s magnitude. For this reason, our results indicate that the sulfur heteroatom in asphaltenes should be addressed. However, new studies must be conducted by increasing the number of substituents, CO2 numbers, and the model size.
The Effect of Credit among Micro, Small, and Medium Enterprises on Income Inequality in Indonesia
Authors: Desfiandi Alvin , Putra Rama Prima
Published: August 2024

Income inequality has become a growing global concern during the last two decades. High income inequality can hinder economic growth, and in the case of Indonesia, the Gini coefficient continues to show an increasing trend. One of the factors that increase the level of income inequality is inequality in business opportunities and access to capital. To address this issue, the government created a credit program to benefit micro, small, and medium enterprises (MSMEs). MSME loans are basically designed to increase equality through the promotion of business opportunities. The authors seek to study the impact of MSME credit on income inequality in Indonesia using panel data with random effects in 33 provinces from 2005-2016. The results of this study are expected to provide an overview of whether the existing MSME credit program has been running effectively or not.
The Effect of Strategic Leadership On Sustainable Competitive Advantage
Authors: Kartika Levina
Published: August 2024

This research aims to analyze and identify the effect of strategic leadership on sustainable competitive advantage. This study uses quantitative method with descriptive and associative research. The population includes employees of PT X (heavy equipment trading company), with a sample of 30-500 respondents. The results show that strategic leadership has a positive effect on sustainable competitive advantage applied by respondent. Testing the strategic leadership effect on sustainable competitive advantage produced a significance value of 0.000 < 0.05, with a correlation coefficient value of 0.927. It can be concluded that strategic leadership has a strong influence on sustainable competitive advantage, with a correlation coefficient value of 0.927. Within this study, the majority of respondents expressed agreement with the questionnaire statement in this research regarding the strategic leadership variable, with 16 statement indicators submitted by the researcher and the sustainable competitive advantage (Y) variables, with 14 statement indicators submitted by the researcher.
The Implementation of Value Co-Creation in the Food Industry
Authors: Yuliawati Asri Anisa
Published: August 2024

In this study, we analyse, and classify the literature that discusses the implementation of value co-creation in the food industry. For this purpose, we conducted a systematic literature review identified from Scopus database search results. Then, it was further screened and filtered to obtain specific literature that could answer the proposed research question. Our analysis focuses on how those studies put value co-creation into real business and industrial contexts. We are looking at the value co-creation phases, mechanisms, and how those could create particular value. We found that value co-creation can be implemented in various ways tailored to the context that the actors wish to achieve. Another classification is made to find out the focus of the present research. This classification is based on the different functions they were focusing on across the food industry. Finally, we organise and summarise the suggestion for future research directions
Efektivitas dan Efisiensi Anggaran pada Sekolah Staf dan Pimpinan Lembaga Pendidikan dan Pelatihan Polri
Authors: Ardiansyah Ardiansyah
Published: August 2024

This research aims to analyze the effectiveness and efficiency of budget absorption at the School for Staff and Leadership of the Republic of Indonesia Police Education and Training Institute (Sespim Lemdiklat Polri) in 2021-2022. The research data is secondary data from Budget Realization Reports for 2021 and 2022, obtained directly from the research object. The research method used is descriptive quantitative. This research found that 2021 budget absorption performance could have been better, as shown in the ULP (Food Sides) & Extra Fooding program, Sespimmen educational operations, and Sespimmen KKL (Field Work Lecture) costs. Meanwhile, in 2022, budget absorption performance will still not be optimal for the ULP & Extra Fooding program. It is because the COVID-19 pandemic allows learning/training activities at the National Police Sespimmen to be carried out online, thereby allowing for savings and budget absorption that could be more optimal. Due to limited data, this research cannot measure effectiveness and efficiency based on the number of programs or activities. So, effectiveness and efficiency analyses are only based on budget data and actual expenditure. Therefore, suggestions for further research are to analyze the effectiveness and efficiency of spending by comparing the number of programs or activities. So, the effectiveness and efficiency of spending per unit program or activity can be seen.
Analisis Kinerja Perusahaan Sebelum dan Saat Pandemi serta Pengaruhnya terhadap Nilai Perusahaan
Authors: Benarivo Hiras , Masripah Masripah
Published: August 2024

This study aims to conduct tests and analyses related to differences in financial performance before and after the COVID-19 pandemic and to see whether financial performance affected the value of food and beverage companies listed on the Indonesia Stock Exchange in 2018-2021. This research proxies firm value using price-to-book value (PBV). Meanwhile, financial performance is divided into three independent variables: Return on Assets as a measure of profitability, receivable turnover, and debt-to-equity ratio (DER) as a measure of leverage. This quantitative research method uses purposive sampling so that 23 companies are obtained, 46 samples for the different tests, and 92 samples for the influence test. This research used the paired sample t-test and the Wilcoxon test for the difference test, and the panel data regression test was used for the effect test. Processing data is carried out using the STATA Version 16 application. Based on the results of the tests that have been carried out, it is found that profitability differs between before and during the COVID-19 pandemic. In contrast, receivable turnover and leverage have no difference. Lastly, the influence test in this study shows that profitability significantly affects firm value, while accounts receivable turnover and leverage do not affect the firm value.
Estandartes de Frevo
Authors: Selva Laura Mendes , Valério Erinaldo Dias
Published: August 2024

O objetivo deste artigo é investigar como os estandartes atuam como suporte documental colaborando com a preservação da cultura e memória do frevo. Para alcançar tal objetivo, a pesquisa fez uso de ferramentas metodológicas tendo como base o Método Quadripolar de Paul De Bruyne, Jacques Herman e Marc Schoutheete (1977), agregado a isso a revisão bibliográfica, o estudo de caso e a descrição, para que seja possível construir uma investigação com base teórica sólida junto ao recorte social escolhido. Com isso, as contribuições teóricas dos autores Paul Otlet, Suzanne Briet, Niels Lund, Bern Frohmann e Michael Buckland foram utilizadas para compreender o conceito de documento e suas aplicações, considerando também os objetos materiais tridimensionais enquanto suporte documental. Em suma, obteve-se enquanto resultado que o estandarte carrega consigo informações relevantes para identificar e representar grupos sociais, por causa das relações objetivas e subjetivas que são estabelecidas entre eles. Tendo em mente que esta não é a primeira nem a última análise acerca dos estandartes carnavalescos, enfatiza-se que este é um instrumento de difusão do conhecimento e de estímulo à reflexão sobre os objetos materiais que carregam consigo vestígios da história, cultural e memória social.
Effects of Nicotinamide Mononucleotide Supplementation on Muscle and Liver Functions Among the Middle-Aged and Elderly: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Authors: Wang Jian-peng , Wang Li , Wang Ting , Zhang Yi-dan , Zhou Ao-jia , Wang Zi-ping , Xiong Zhang-e
Published: August 2024

Introduction:

Nicotinamide Mononucleotide (NMN) has gained attention as a precursor
to Nicotinamide Adenine Dinucleotide (NAD+) in recent years, commonly utilized in
anti-aging therapies. The anti-aging effects of NMN on muscle and liver functions in middleaged
and elderly people are still unclear.

Objective:

Based on available randomized controlled trials, we conducted a meta-analysis to
evaluate the impact of NMN on muscle and liver functions in middle-aged and elderly individuals.

Methods:

We conducted searches on three electronic databases (PubMed, Embase, Web of Science)
for randomized controlled trials involving NMN interventions in middle-aged and elderly
populations. Through the Cochrane Handbook, we assessed the specific methodological quality.
All statistical analyses were obtained by Stata15, and statistical significance was set as P<0.05.

Results:

There were 412 participants from 9 studies in this meta-analysis. Based on changes in
gait speed (SMD: 0.34 m/s, 95%CI [0.03, 0.66] p = 0.033), NMN had significant effects on muscle
mass. Moreover, NMN had a better effect on ALT (SMD: -0.29 IU/L, 95%CI [-0.55, -0.03] p
= 0.028). Subgroup analysis indicated that administering a small dose of NMN exerted the most
prominent impact on Homeostasis Model Assessment-Insulin Resistance (HOMA-IR).

Conclusion:

NMN has positive efficacy in enhancing muscle function, reducing insulin resistance
and lowering aminotransferase levels in middle-aged and elderly individuals. NMN is
an encouraging and considerable drug for anti-aging treatment.
Current Approaches on Transfersomal Patch: A Noninvasive Innovative Booster for Improved Transdermal Drug Delivery
Authors: Khamkat Piyali , Barik Vivek , Mohapatra Snehamayee , Karati Dipanjan , Mukherjee Swarupananda
Published: August 2024

Pharmaceutical research is increasingly focusing on transdermal drug delivery due to
its potential for improved compliance and bioavailability. However, it is challenging due to the
tight intracellular junctions present in the skin. Researchers have developed noninvasive methods,
like transfersomes, to overcome these challenges. Transfersomes are ultra-deformable vesicles
utilized for improved transdermal applications. They are made up of a phospholipid-rich
lipid bilayer, an edge activator, and an ethanol/aqueous core. After topical treatment, transfersomes
can penetrate deeper skin regions, delivering larger concentrations of active compounds.
A transfersomal patch is applied to the skin and left for an extended period of time to allow a
large dose of medication to permeate into the bloodstream. The transfersomal patch offers an
advantage over the transfersomal gel because it allows the transfersomes to be applied under
occlusive conditions, resulting in greater permeability, a lower amount of active medication, and
a steady supply rather than a massive dose. This review represents the preparation and evaluation
of transfersomal patches, recent research approaches, and future aspects of transfersomal
patches. This study suggests that drug-loaded transfersomal patches could be a unique option to
avoid invasive therapy.
Genomic Face-off: An In Silico Comparison of the Probiotic Potential of Lactobacillus spp. and Akkermansia muciniphila
Authors: Fakruddin Md. , Karim Md. Abu Bakar , Ul Islam Bakhtiar , Safa Ashrafus , Sultana Jinath , Bulbul Nayeema , Shishir Md. Asaduzzaman
Published: August 2024

Introduction:

The gut microbiota plays a crucial role in maintaining human health, and
probiotics have gained significant attention for their potential benefits. Among the diverse array of
gut bacteria, Akkermansia muciniphila, and Lactobacillus spp. have emerged as promising candidates
for their putative probiotic properties.

Methods:

In this study, we conducted a comprehensive comparative in silico analysis of the
genomes of A. muciniphila and Lactobacillus to decipher their probiotic potential. Utilizing a
range of bioinformatics tools, we evaluated various genomic attributes, including functional gene
content, metabolic pathways, antimicrobial peptide production, adhesion factors, and stress response
elements. These findings revealed distinctive genomic signatures between the two genera.
A. muciniphila genomes exhibited a high prevalence of mucin-degrading enzymes, suggesting a
specialized adaptation for mucin utilization in the gut environment.

Results:

Additionally, the presence of specific pathways for short-chain fatty acid production highlighted
its potential impact on host health. Lactobacillus genomes, on the other hand, demonstrated
a diverse repertoire of functional genes associated with probiotic attributes, including the production
of antimicrobial peptides and adhesion factors, indicating potential for host-microbe interactions
and immune modulation. Furthermore, this analysis unveiled the genetic basis of stress tolerance
in both genera, revealing conserved mechanisms for surviving the dynamic conditions of
the gut ecosystem.

Conclusion:

This study also shed light on the distribution of antibiotic-resistance genes, allowing
us to assess safety concerns associated with their potential use as probiotics. Overall, this comparative
in silico exploration provides valuable insights into the genomic foundation of A. muciniphila
and Lactobacillus probiotic potential. These findings contribute to the understanding of their respective
roles within the gut microbiota and offer a foundation for further experimental investigations.
As probiotic applications continue to expand, this study advances our knowledge of the genetic
underpinnings that govern their functionality and highlights promising avenues for future
therapeutic interventions and personalized health strategies.
Hot Water Immersion as a Means to Prevent Cardiovascular Disease and Associated Mortality
Authors: Kjertakov Metodija , Petersen Aaron
Published: August 2024

Physical activity is widely promoted as a preventive strategy against cardiovascular
disease and death from this disease. However, the fact that some individuals are unable or unwilling
to engage in physical activity highlights the need for alternative strategies. Passive heat
exposure using hot water immersion could serve as an alternative to physical exercise, as it provides
similar, if not greater, cardioprotection than physical activity. This perspective article presents
evidence supporting our concept and provides recommendations for hot water immersion
sessions.
Endometriosis: A Comprehensive and Concise Review of Potential Biomarkers and Treatment Therapies
Authors: Aziz Namra , Wal Pranay , Pyne Chandana , Singh Shweta , Borkar Sudarshan N. , Pandey Swarnima , Sharma Mukesh Chandra
Published: August 2024

Females of reproductive age can develop endometriosis, an inflammatory gynecological
illness that is hormone-dependent. The variable lesions that make up the functional endometrium
outside of the uterus cavity are what set this disorder apart in terms of its clinical and pathological
aspects. Around 10% of women in their reproductive years have endometriosis worldwide,
which significantly lowers their quality of life overall. Infertility and chronic pelvic discomfort are
the two main symptoms that significantly affect women's reproductive health and general well-being.
The pathophysiological underpinnings of endometriosis remain unclear despite years of intensive
research. Understanding the fundamental mechanisms that produce endometriosis is crucial,
as demonstrated by the substantial public and private health consequences. This article offers an
overview of recent advancements in biomarkers regarding endometriosis treatment options, based
on a thorough literature study.
Quality by Design Optimization of Telmisartan-loaded Self-nanoemulsifying Drug Delivery Systems
Authors: Maharana Rajib Lochan , Swain Suryakanta , Mahapatra Santosh Kumar , Jena Bikash Ranjan
Published: August 2024

Aim:

This study aimed to develop a QbD-based SNEDDS for Telmisartan to enhance its biopharmaceutical performance.

Background:

Quality by Design (QbD) was incorporated by selecting the Critical Process Pa-rameters (CPPs) as influential variables upon the desired responses. Using Design of Experiments (DoE) software, oil, and S/CoS were tested for pre-isotropic compatibility and formulation im-provement. A heating-cooling cycle and phase separation were used to determine the formula-tions' dispersibility, self-emulsifying time, mean globule size, and stability.

Objective:

Using Design of Experiments (DoE) software, oil (Capmul MCM C-10) and surfactant (Labrasol)/co-surfactant (Tween-20, and PEG-600) (S/CoS) ratios were optimized for pre-isotropic compatibility and formulation improvement.

Methods:

Aerosil-200, Sylysia-350, 550, and 730 were used as porous carriers, and Neusilin US2 as an adsorbing agent resulted in free-flowing granules of self-nano emulsifying drug delivery systems. The SNEDDS was further formulated into tablets using a direct compression technique with enhanced disintegration properties.

Results:

The prepared SNEDDS tablets exhibited a 71% increase in drug dissolution as compared to the pure drug and marketed formulation after the in vitro dissolution studies.

Conclusion:

This QbD approach offers a promising strategy for developing SNEDDS formula-tions for poorly soluble drugs like Telmisartan.
Design and Evaluation of Tools for the Psychological Prevention of Injuries in Baseball Pitchers
Authors: Garit Jesús Ríos , Surita Yanet Pérez , Cases Silvia Solé , Romero César Montoya , Reyes Rodríguez Amanda Beatriz , Cárdenas María del Carmen Chávez
Published: August 2024

Aims:

To determine, through the evaluation of experts, the introduction in the professional practice of tools designed for the psychological prevention of injuries in high-performance baseball pitchers in a Cuban province.

Background:

The psychological interventions for primary injury prevention contribute to the transition from the biomedical to the biopsychosocial approach in sports injury care. However, the studies carried out are very scarce, few generalizable and insufficient to facilitate the multidisciplinary work around the psychological preparation of the athlete as a method of prevention.

Objective:

The objective of this study is to evaluate by experts the design of an Android application and procedure to guide the psychological prevention of injuries in high-performance baseball pitchers.

Methods:

A methodological investigation was carried out to design the tools, which were evaluated by 11 experts who had a professional experience between 14 and 41 years (M=26.64; SD=11.74). Using the preference method, an ad-hoc questionnaire was applied to obtain the evaluations, being processed by empirical distribution of frequencies, descriptive statistics, Kendall´s coefficient of concordance and coefficient of variation.

Results:

The theoretical-methodological foundations of the procedure design, the definition of users, stages and functions, the coherence between tasks, techniques, instruments and means, structure and functionality, and the Android application, were highly valued.

Conclusion:

The designed tools have a high level of adequacy, are pertinent and sufficient to contribute to the psychological prevention of injuries, so they can be introduced into the professional practice of sports psychologists, coaches, and baseball pitchers from Villa Clara. However, its application must be accompanied by a process of experimental research to determine its efficacy, effectiveness, and efficiency.
Microstructure and hot deformation behavior of twin roll cast ZAX210 magnesium wire
Authors: KADEN Christoph
Published: August 2024

Abstract. The hot deformation behavior of a Mg-2Zn-1Al-0.3Ca (ZAX210) wire, manufactured by twin roll casting was investigated by hot compression tests conducted at different temperatures (250 – 400°C) and strain rates (0.01 - 10 s-1). The analyses of the microstructure and the texture are determined by an optical microscope and scanning electron microscope. A processing map is developed to identify optimal process parameters. The twin roll cast state shows the presence of {101 ̅2} extension twins, {101 ̅1} compression twins, double twins, and a weak prismatic texture. Furthermore, regions with small recrystallized grains as well as a small segregation line extend across the center of the wire. The heat treatment at 420°C for 2 h results in a grain structure, consisting of equiaxed grains with an average grain size of approximately 32 µm in the center and 17 µm at the edges of the wire. The heat treatment further reduces the segregation and weakens the texture by spreading the basal plane along the transverse direction. In contrast to the initial state, only {101 ̅2} extension twins can be observed. The experimental results of the compression tests show that the flow stress increases with higher strain rates and decreasing temperatures. The course of the flow curves indicate that dynamic recrystallization occurs during hot deformation. The activation energy for plastic deformation of the twin roll cast and heat-treated wire is calculated to 150 kJ/mol. The process map identifies optimal process parameters, while deviations from these parameters result in crack formation, primarily at grain boundaries.
Simulation of texture-related micro-indentation behavior of typical HCP alloy plates
Authors: ZHOU Xiangyu
Published: August 2024

Abstract: The mechanical behaviors of magnesium and its alloys, regulated by the slip and twinning mechanisms, are remarkably influenced by the crystalline orientation. A better understanding and quantification of the mechanisms in deformation is necessary. To this end, the crystal plasticity finite element (CPFE) simulations of magnesium alloy plates have been investigated in this study. The process of impression of single crystal samples with three different declination angles with 0°, 45°, and 90° is simulated. The corresponding detailed CPFE simulations reveal a texture-dependent spatial distribution of extension twins, and the twin morphologies and the indentation topography of single crystals have been discussed, highlighting the influence of the initial texture. Furthermore, the simulations uncover the accumulated shear strain of the deformation system varying with spatial position inside the sample, which is in favor of the analysis of the twin-favor zone.
Development and industrial implementation of a biodegradable surgical wire production technology from ZnMg0.004 alloy: In vitro assessment of degradation rate and mechanical property changes
Authors: MILENIN Andrij
Published: August 2024

Abstract. The paper discusses the technology for the production of the new biodegradable surgical wire, developed at AGH, along with the experience of its integration into INTERMECH's production processes. This wire's basic mechanical and corrosion properties are thoroughly examined. The developed technology is based on the use of a combination of hot and cold (in the last passes) drawing of a workpiece obtained by hot extrusion. Hot drawing allows to achieve the necessary ductility of the wire, while the final cold drawing improves the surface quality, which is important in the context of the biological properties of the wire. To assess biodegradation rates, in vitro testing was conducted within a natural corrosive environment (using bovine serum from Biowest). Mechanical tensile tests were performed on wires at various stages of corrosion, ranging from 3 to 30 days, in addition to the original wire. These tests were carried out using a Zwick 250 testing machine. The study revealed that the tensile strength of all produced wires decreases by less than 50% after 30 days of corrosion. Further experimental investigations were conducted to monitor changes in wire mass over time. The tests spanned 120 days, during which the corrosion rate declined from 2 mm/year in the initial days to approximately 0.05 mm/year in the later stages. This study indicates that when planning the use of this wire in bone surgery, a corrosion time of 1-2 years should be anticipated. In cases where the wire is exposed to intense bodily fluid flushing, this timeline may be shorter.
FEM study of process parameters in a novel superplastic forming of titanium alloy Ti-6Al-4V
Authors: LIU Jun
Published: August 2024

Abstract. A novel hybrid forming process involving the use of hot drawing along with superplastic forming (SPF) is studied here. The hot drawing stage helps in enhancing the formability and in fast deforming the sheet metal into a hollow shape with desired amount of material draw-in. During the subsequent SPF stage, gas pressure was applied onto the pre-formed part to complete the forming process at a targeted strain rate. With the hybrid process, titanium alloy Ti-6Al-4V sheets have been successfully formed in lab-scaled conditions at 800°C in 16 min. In this paper, finite element modelling (FEM) was used to demonstrate the effects of each stage (hot drawing and SPF) during the process. A plasticity model based on tensile test data was adopted as a material model for simulation. The pressure cycle which was predicted from the simulation has been used in the process to maintain the sheet forming at an average strain rate (e.g. 10-3 and 5×10-4 s-1). Material draw-in and thickness distribution were used to compare and optimise the process parameters. The simulations have shown the capability of the model to be used for the hybrid superplastic forming process. The influences of varying process parameters, such as punch geometry, blank size, blank-holder force, friction coefficient and pressure cycle, were investigated by the simulations. It was found that the punch geometry and blank size played significant roles on the thickness uniformity of the final part, from which an optimised hot-drawing system that could lead to minimum thinning has been designed by FEM method.
Effect of grain size on blank holder force of fine micro-blanking for Inconel 718 superalloy foils
Authors: JI Kaisheng
Published: August 2024

Abstract. Regarding product miniaturization, there is a noticeable difference between micro-blanking and macro-blanking in terms of the quality of the parts and the metal deformation behavior. In this paper, fine micro-blanking simulations were conducted on Inconel 718 foils with a thickness of 100 μm and different grain size to investigate the effects of different blank holder force on the fracture length of blanking surface. The results showed that the empirical (macro) formula of blank holder cannot apply to fine micro-blanking. The fracture length gradually decreases with the increase of blank holder force. And as the grain growth, the blank holder force to obtain a micro-blanking surface with full burnish length and no fracture zone was smaller. Based on the effect of grain size and blank holder force, a revised empirical formula of blank holder force was established for fine micro-blanking. Then, the fine micro-blanking experiments of Inconel 718 superalloy foils were conducted to evaluate the feasibility for the revised empirical formula of blank holder force. This work may contribute to the selection of forming force for fine micro-blanking applications.
Environmental impact assessment and comparative analysis of hot stamping and cold stamping processes: A cradle-to-gate lifecycle assessment study
Authors: BUCCONI Marco
Published: August 2024

Abstract. This manuscript presents the results of a cradle-to-gate lifecycle assessment (LCA) conducted on a component manufactured through two distinct process routes: Hot stamping of AA6082-T6 and cold stamping of AA5251-H22. The primary objective of this study is to provide a detailed understanding of the environmental impact associated with these processes and to conduct a comparative analysis of their environmental profiles. A comprehensive process map was developed for each manufacturing route, delineating all inputs and outputs at each step. Forming trials were executed during the LCA, capturing equipment energy consumption. When immediate data was unavailable from trials, the LCA model was supplemented with information from the Ecoinvent 3.6 database. The analysis demonstrates that the adoption of advanced near-net-shape manufacturing, specifically hot stamping, can significantly diminish the environmental impact compared to traditional cold stamping processes. Despite the additional energy requirements for heating in hot stamping, the overall environmental savings, supported by uncertainty analysis, are considerable. In the case of the examined demonstrator part, hot stamping showcased a noteworthy 35% reduction in CO2 equivalent emissions, equivalent to 6 kg CO2e per part. This reduction is primarily attributed to two key factors: the decreased material thickness achievable in hot stamping while preserving equivalent mechanical characteristics in the final part and the recycling of any material waste after forming. The results underscore the environmental advantages of embracing advanced manufacturing techniques, contributing valuable insights for environmentally conscious decision-making in the manufacturing industry.
Analysis of the influence of spinning temperature on the coordinated deformation of Mg/Al composite tube
Authors: ZHENG Jinbin
Published: August 2024

Abstract. Currently, the focus of research in the realm of Mg/Al layered metal composites predominantly lies within the domain of plate structures, while the development of Mg/Al bimetallic composite tubes (BCTs), which hold significant utility, remains in its nascent exploratory phase. Among the various forming methodologies applied to BCTs, the spinning process has garnered considerable attention due to its advantageous attributes encompassing minimal forming loads, uncomplicated tooling requirements, cost-effectiveness, and high dimensional precision. This study delves into the outcomes of forming Mg/Al BCTs at diverse spinning temperatures via a synergy of theoretical frameworks and simulation experiments facilitated by the Simufact Forming software platform. A novel approach is presented for assessing the degree of coordinated deformation at the interface by scrutinizing the interface strain gradient, elucidating the intrinsic correlation between the interface strain gradient and the bonding strength at the interface. Through meticulous analysis, it is discerned that the BCTs exhibit the least interface strain gradient and axial extension disparity when subjected to a spinning temperature of 350°C. Consequently, in the context of spinning preparation for Mg/Al BCTs, a spinning temperature of approximately 350°C is recommended to engender Mg/Al BCTs characterized by enhanced harmonized deformation properties.
Segmented blank holder concept to influence the forming zone during incremental bending
Authors: PANICK Daniel
Published: August 2024

Abstract. Decreasing batch sizes and a simultaneous increase in the number of variants are developments in production technology that can no longer be managed economically using conventional mould technology with rigid, product-specific functional surfaces for semi-finished products. Individual or even in-line reconfigurations of the tool’s functional surfaces are being investigated to meet production requirements. Moreover, the goal is to control these surfaces during the process to compensate fluctuations, e.g. in semi-finished products. Incremental swivel bending (ISB) is a process for flexible bending forming in which the bending moment is transferred to the semi-finished product by friction by means of the clamping surfaces of the blank holder. In addition to the geometric and mechanical properties of the semi-finished product, the contact normal force and friction are responsible for the size and shape of the forming zone. In this paper, established analytics are utilized to present a tool concept that enables the clamping force distribution to be specifically adjusted by means of adjustable segmented hold-down surfaces with a vertical degree of freedom and, as a result, the size and shape of the forming zone to be influenced. The potential for extending the limits of forming technology is then discussed regarding the numerically determined local strain distribution through the dynamic loading and unloading of the clamping surface segments during incremental forming with the overall goal to achieve an in-process controllable material flow during sheet metal forming.
Investigation of mesoscale deformation and damage behaviour in high-carbon bearing steel via multiscale simulations and experiments
Authors: WANG Huiling
Published: August 2024

Abstract. High-carbon steel is susceptible to micro-defects owing to the heterogeneous microstructures during forming, which seriously deteriorates the fatigue life. However, the investigation of the damage behavior during cold deformation remains largely undisclosed in these steels, which hinders further control of the microstructure and forming process. The current work investigates the deformation and damage characteristics of high-carbon steel composed of soft ferrite and hard cementite particles. A methodology coupled with multiscale simulations and experiments is applied to analyze large plastic deformation and damage characteristics. The simulation utilizes nanoscale molecular dynamics simulation to obtain matrix-particle interface strength properties. The Rice-Tracey fracture model and Weibull distribution capture experimental fracture characteristics of matrix and particles. The above failure criteria are incorporated within a real microstructure-based representative volume element (RVE) to conduct the mesoscale deformation and damage process in the spheroidized ferrite-cementite steel. Additionally, in-situ SEM uniaxial tensile tests are carried out to assess the damage mechanism and validity of the mesoscale simulation. The numerical simulation exhibits a well coincidence with the experimental trends in damage evolution of the individual particles, matrix, and matrix/particle interfaces. It is also observed that damage is a function of inherent particle properties, particle morphological features, and matrix strain localization characteristics. Larger-size and long-striped particle undergoes fracture at an earlier stage. Consequently, the incompatibility and stress concentration between matrix and particles affect the strain localization characteristics. As a result, higher stresses inside strain localization bands results in the increase of void damage initiation and growth along the interfaces. Overall, the way of matrix/particle decohesion should be marginally higher compared to particle fracture, which primarily dominates the final fracture of the high-carbon bearing steel.
Effects of network-distributed TiB on dynamic recrystallization of TiB/(TA15-Si) composites during the deformation in β phase region
Authors: LI Liting
Published: August 2024

Abstract. To study the effects of network distributed TiB on dynamic recrystallization of high temperature β phase of near α titanium matrix composites, the TiB/(TA15-Si) composites were compressed under 1000℃ with strain rates ranging from 1 s-1~0.01 s-1. Results show that the flow stress was sensitive to strain rates. During hot compression, the microstructure evolution included single TiB rotation, network structure changing from circular to oval, and dynamic recrystallization (DRX) of high temperature β phase. The mechanism of DRX was continuous and discontinuous DRX mixed mechanism. Attributed to the accelerative effects of TiB by providing nucleation sites and improving storage energy, DRX preferentially occurred around TiB. After compression, equiaxed grains of high temperature β phase were formed in TiB rich region, while elongated grains were formed in TiB lean region. The dislocations density in elongated grains at higher strain rate was higher than that at lower strain rate. Under high strain rate, high temperature β phase was dominated by DRX in TiB rich region and dynamic recovery in TiB lean region. Under lower strain rates, high temperature β phase was dominated by the growth of DRX grains.
The influence of dynamic characteristics of six-bar linkage mechanical press transmission system on the accuracy of slider
Authors: ZHAI Hua
Published: August 2024

Abstract. The six-bar linkage mechanical press is a crucial equipment in the preparation of metal bipolar plates for fuel cells. The dynamic characteristics of the transmission system have a significant impact on the precision of the slide operation, which directly affects the quality of the bipolar plate forming. In this article, A dynamic model of the six-bar linkage transmission system under complex forming workloads was established to research dynamic characteristics. The dynamic characteristics of each bar was analyzed under load conditions. Combining with the orthogonal experimental method, we investigate the various parameters influence on the press slide precision. Through an six-factor orthogonal experiment, the results show that the down-push rod dynamic characteristics are the most important factor affecting the slide stroke precision under the transmission system's workload conditions. Therefore, it is necessary to optimize the down-push rod design and manufacturing process. The results of this study have a certain reference value for the design and optimization of the six-bar linkage mechanical press, and the improvement of the quality of metal bipolar plate preparation for fuel cells.
Residual stress and part distortion prediction in L-PBF of Ti-6Al-4V using layer-by-layer FEM simulation
Authors: Pollara G.
Published: August 2024

Abstract. Due to its ability to accommodate customer demands and produce objects with complex shapes, Laser Powder Bed Fusion (LPBF) has been widely adopted in numerous industry areas, including biomedical, automotive, and aerospace. Even with all the benefits that LPBF has to offer, its use may be limited by the development of residual stress according to the strong thermal gradients produced throughout the process. Residual stresses within the samples can result in part distortion after the removal from the built platform or even in part failure during the process if the residual stresses are excessive. In order to save time and costs, numerical simulation can be an effective tool to predict residual stress and part distortion in opposition to the trial-and-error approach which involves an expansive and time-consuming experimental campaign. To this aim a finite element method (FEM) together with a layer-by-layer approach was used in this study. Numerical simulations were performed on the commercial software DEFORM-3D™ with which different values of laser power were investigated. Moreover, the influence of the voxel mesh on the FEM model accuracy was also investigated.
A review of deep neuron network applications in extrusion die design
Authors: DING Jiangfeng
Published: August 2024

Abstract. Ensuring the quality of extrusion product necessitates meticulous die design, typically achieved through simulation iterations and/or experimental trials. However, this process is not only time-consuming but also costly. Despite substantial research utilizing historical data and finite element analysis (FEA) to elucidate design guidelines and principles, and the existence of numerous empirical equations guiding die design, it remains more of an art reliant on the designer's experience. In contrast, Deep Neural Networks (DNNs) have the capability to capture design experience with appropriately defined inputs and outputs, transforming it into abstract features for further application. With the advancement of DNNs, the automatic generation of precise die designs has become achievable. Several research studies have been undertaken to enhance die design through the application of DNNs, particularly Convolutional Neural Networks (CNNs). CNNs, a machine learning method commonly applied to extract information from images, have been utilized due to the intricate nature of die design. Given the inherent characteristics of DNNs, a significant challenge in incorporating DNNs into die design lies in devising a scheme to abstract 3D die designs for defining inputs without loss of information. Various methods exist for handling 3D objects, such as point clouds or projecting 3D objects into 2D depth graphs. Nonetheless, most of these methods prove challenging to implement effectively in the realm of die design. Another challenge stems from the overall complexity of the extrusion die. While most research has focused on automatically designing specific features of the die, such as the location or shape of portholes, there have also been data-driven studies attempting to generate entire die designs using historical data. This paper aims to review the status of the application of DNNs in hot extrusion die design and explore the further potential in this field.
A customized design tool incorporating web and client functions for new mechanical presses
Authors: NI Jun
Published: August 2024

Abstract. To improve the design efficiency and consistency of many new mechanical presses developed by a few engineers, an application with two tabs was proposed to incorporate a web browser and a client window, respectively, for the press modification and the new press design. The press modification is based on the standardized press data in server while the new press design adopts the functions of Computer-Aided Design (CAD) and Word processing tools in local computers. For the press modification: (1) a case retrieval function was developed to find similar features of standardized press information that was then adapted to meet the new custom order; (2) some structural parameters and component selections were adjusted and checked by the calculation algorithms and material properties; (3) within the browser tab, design document was eventually reported. For the new press design: (1) besides the BOM templates, two dimensional (2D) sketch templates were summarized for non-standard parts or assemblies including the machine frame, crank, links, slider, work-table, etc.; (2) the slider movement design and dimensional allocation of press components were performed according to a series of interactive dialogs, answers and views with regard to the custom order; (3) the dot net framework was adopted to integrate Solidworks, Auto CAD and Word functions to generate parts, assemblies, drawings and the Bill Of Materials (BOM) from the 2D sketch and BOM templates using the dimensional allocations and the design results. Examples validated the feasibility of the proposed tool.
Integrating Numerical and experimental analyses for the realization of pre-detection of delayed fractures on punched surfaces of ultra-high-strength steel sheets
Authors: UEDA Yuya
Published: August 2024

Abstract. A key challenge encountered in finite element (FE) punching simulations is accurately capturing the arrest or delay in crack propagation during punch penetration. Conventional methods relying on element deletion demonstrate inadequacies in representing crack arrest, particularly complicating the simulation of the punched surface states in scenarios with minute clearances. This study introduces a novel approach for fracture representation in FE punching simulations, wherein cracks were integrated as perimeter lines during the remeshing process. Utilizing observation-driven crack propagation paths and arrest behaviors, we analyzed the residual stress on punched surfaces under minimal clearance conditions. Results indicate that for 22MnB5 hot-stamped steel, the residual stresses within the interior side of the burnished region can exceed 1 GPa in cases with a 10-μm clearance.
Multi-scale numerical modeling of the multi-pass rolling texture evolution by using crystal plasticity and finite element method
Authors: BYRSKA-WÓJCIK Dorota
Published: August 2024

Abstract. The finite element method (FEM) combined with the crystal plasticity (CP) model was used to predict crystallographic texture evolution during multi-pass asymmetric rolling of the polycrystalline aluminum with tilted entry into the rolling gap. The FEM macro-scale model of the rolling process with various asymmetry was performed using Abaqus commercial software. The asymmetry was introduced by difference in the diameters of cooperating rolls and various tilt angles of the rolled bar entry into the rolling gap. Predicted stress distribution over sample volume was used as the boundary conditions in the crystal plasticity meso-scale model of the plastic deformation. The CP meso-scale model developed by Leffers and Wierzbanowski [1], [2] was used as a post-processing procedure. The predicted evolution of the rolling texture distribution on the rolled bar thickness turned out to be in good agreement with that measured for specimens rolled with the same parameters as the ones used for modeling. Impact of the rolling parameters on the texture evolution was found.