bluuebunny/crossref_metadata_2025 huggingface dataset:
Blue Economic Concept on Protecting Marine Ecosystem in Indonesia and China
Authors:   International Business Law, Universitas Prasetiya Mulya BSD City Kavling EdutownI.1, Jl. BSD Raya Utama No.1, BSD City, Kec. Pagedangan, Kabupaten Tangerang, Banten 15339, Khairunnisa Fadhila
Published: April 2023

The concept of the Blue Economy is an economic principle for sustainable development, which was first introduced at the United Nations Conference on Sustainable Development in 2012, for Southeast Asian countries was also introduced at the APEC Summit held in 2013. This concept is expected to be able to solve the problems of marine ecosystems caused by marine-based economic activities, such as the problem of overfishing since 2017, and the problem of marine debris both from land and waste from economic activities at sea – garbage mining and marine tourism. Indonesia's marine-based economy without a doubt has potential to be improved and has to be in line with protecting and preserving the environment and the ecosystem with this concept. One of the countries that have regulated this concept and succeeded in increasing its marine-based economy is the People's Republic of China (PR China). This journal uses normative methods and comparative studies to find out how both countries regulate the protection of marine ecosystems while maximizing the use of it as part of economic activities, and what lesson Indonesia can learn from PR China in its maritime regulations to encourage the improvement of marine-based economic income.
Imigrantes Negros em Situação de Rua no Reino Unido:
Authors: Tavares Breitner
Published: April 2023

Para uma melhor compreensão da efetividade das políticas de assistênciasocial e saúde coletiva referentes às condições da população emsituação de rua na Inglaterra, apresenta-se neste ensaio uma metodologiaque privilegia uma análise mais descritiva das políticas públicas− com alguns marcos institucionais em relação à política imigratóriae de assistência à saúde − e suas consequências quanto ao serviço desaúde em tempos de Brexit. Apresenta-se, também, uma abordagemmetodologicamente qualitativa de uma instituição de acolhimento,que permite compreender aspectos da sociabilidade da população emsituação de rua em seu perfil transnacional, que mais recentementesofre uma redefinição pelo viés da imagem estigmatizada do imigrante,sobretudo o de origem negra caribenha e africana acolhidos numalbergue em Leeds - Yorkshire.
Ilegalismos e Sociabilidades Transnacionais:
Authors: Couto Otávio
Published: April 2023

Apresentar um espaço fronteiriço cujas interações sociais são determinadasessencialmente através de mobilidades clandestinas, revelarimpactos dessas mobilidades na gestação de mecanismos de controlesocial em solo francês e analisar o processo de mitigação do crimeem Oiapoque em prol da subsistência de mercados ilícitos típicos daregião. Esses são os objetivos deste artigo, etapa preliminar de um estudomais amplo realizado através de pesquisa qualitativa de cunhoexploratório, documental e bibliográfico, que se propôs lançar luz sobreilegalismos transfronteiriços de um Brasil profundo cujas ressonânciasainda permanecem obscuras.
Os Dirigentes Da Cultura:
Authors: Barbalho Alexandre
Published: April 2023

O artigo investiga a lógica de nomeação da elite dirigente do Ministérioda Cultura durante a gestão do ministro Francisco Weffort nos governosde Fernando Henrique Cardoso (1995-2002), com o objetivo deentender como a montagem do gabinete se relacionou com o campopolítico, em um período de alto grau de fragmentação partidária e cultural.Como ferramenta metodológica, se constituiu um banco de dadosbiográficos sobre os agentes. O trabalho concluiu que se tratava depessoas cujas trajetórias e distintas competências correspondiam aoscargos ocupados, trunfos que se combinaram com relações pessoais e/ou partidárias, distinguindo-os do burocrata e do político.
Informational Vulnerability of Russian University Students to Adverse Impact of Social Media
Authors: Kiselev V. M.
Published: April 2023

Concern for the health of young citizens is a major task of our state, it was included in the target program ‘Research and Development on Priority Lines of Developing Scientific and Technological Complex in Russia for 2014-2021’. This concern can be realized relying on effective technologies of influencing media, popularization of healthy life style, etc. However, not a single social and psychological theory can cover the whole diversity of social world, but each of them can more or less adequately explain separate, local aspects, phenomena, facts and regularities. The goal of the article is to verify the hypothesis about possible foresight of events and their drastic consequences, including youth extremism, which can take place in case of young students’ exposure to adverse impact on the part of media and about expediency to protect students at every university from this factor. Nature of this phenomenon and consequences of its proliferation have been analyzed in various academic works. Multi-disciplinary methods can be useful for studying the problem. Sociological methods collect and process information mainly in the form of survey and document analysis (event registration, information gained from respondents). The use of neuro-physiological methods stipulates device registration of neuro-physiological processes in the cerebral cortex and adjoining sub cortex zone, which cause psychic functions of the human being uncontrolled by him/her. Philosophy uses logical methods to find reasons of phenomena and their consequences. The combined use of these inter-disciplinary theories and research methods can help reveal sociological and philosophic aspects of social media, understand nature of their impact on student behavior. By social media calls for extremism and terrorism are spread among students and in conditions of present information war waged by western special services against the Russian Federation it is extremely risky and requires a quick response. Findings of the research can help find effective sociological counteraction against youth extremism and terrorism.
Compensatory Mechanism of Rational Management of Natural Resource Use at Russian Enterprises
Authors: Demidov A. V.
Published: April 2023

Working-out new approaches to ecology-oriented development of national economy requires new highlytechnological and science-intensive enterprises putting out products with high level of added value at the expense of introduction of innovation ecologically effective technologies and complex ecological modernization of Russian enterprises. The article analyzes strategic goals of ecologically sustainable well-balanced development of the Russian Federation up to 2050 and provides key trajectories of their attaining. The fact of ignoring green growth parameters in governmental strategic documents was proved. On the basis of the present research compensatory mechanism of managing rational natural resource use and algorithm of its practical realization were worked out. It could compensate for the damage incurred to ecosystems and ensure preservation, restoration and increase in lifeproviding conditions of the environment in accordance with the level of negative impact on the environment within the frames of fundamental provisions of the author’s concept of balanced interaction of society and nature as a basis of sustainable development of the world.
Finance Risks and Sources of Financing Sustainable Development: Global and Russian Aspects
Authors: Khominich I. P. , Duc Nguyen Huu
Published: April 2023

In times of sharp aggravation of the sanction war against the Russian Federation, global power crisis and highest geo-political and geo-financial risks the world community, including the Russian Federation, keeps on moving towards carbon neutrality. It takes place in spite of dropping global investment caused by the pandemic and sanctions, reduction in carbon deals and turbulent finance and power markets. On this way within the frames of the green agenda serious risks such as deficit of sustainable development financing, low share of undeveloped countries and prevalence of state funds in financing were encountered. The article estimates investment needs of the global program of sustainable development by industries, where the highest share falls to power engineering. It identifies sources of investment: private capital of institutional investors, international finance organizations, international banks of development and state funds. And finally, it provides expert opinions of the IMF concerning the volume of deficit in financing and problems of undeveloped countries, which due to limited national finance markets cannot use market financial tools of investment raising for projects of green technologies. The authors focused on the most capital-intensive industry of the green agenda, i.e. power and on energy-transition to carbon neutrality. They pointed out to finance risks of energy-transition and such urgent problems, as searching for sources of financing, for investors that are ready to put capital into risky low-carbon projects with a long pay-back period, building new finance schemes of participant interaction, developing innovative finance products.
Challenges and Pre-Conditions of Green Financing Development
Authors: Magomedova G. M.
Published: April 2023

The article deals with an acute topic connected with sustainable development, i. e. the development of green financing. Raising capital for green investment was limited due to micro-economic problems dealing with internationalization of external factors, informational asymmetry, inadequate analytical potential and vague definition of the notion ‘green’. Green bonds mean various debt tools, after flotation of which earnings go to financing or refinancing of effective or new green projects. The article describes stages of green bond market development, characterizes participants of this trend and shows voluntary standards of green bonds that should be used for their issuance. The principle goals of green finance are to internationalize ecological external factors and reduce risk perception, to stimulate investment that could provide ecological advantages. The author studies benefits and structure of green bonds by aims of using profits and shows pre-conditions of green financing development. They are creation of favorable environment, support of business climate, provision of bank regulation bodies with authorities to supervise ecological risks of the finance sector and law supremacy and investment regime, which could promote growth in green investment activity.
Regulation and Structuring of Budgeting Process in Commertcial Organization as Factor of Providing Effectiveness of Budgeting Subsystem
Authors: Asriev S. V. , Nazarova T. O. , Pavlenko I. A.
Published: April 2023

Important components of effective organization of budgeting subsystem in commercial structures are clear definition of norms and rules of its building, identification of its place and role in the information system of management support and fixing clear-cut, comprehensive regulation of carrying-out concrete steps for each responsible employee. The authors found certain aspects of the present problem, which require well-grounded specification. After studying regulation and structuring of budgeting, a conclusion was drawn that budgeting is not only expedient but necessary for budget in order to guarantee its safe and sustainable development. Criteria idea of the fact when budgeting can be expedient for business is presented in the article. Specifications concerning periods of budgeting in view of certain indicators (budgeting items) are also provided. The authors show advantages and drawbacks of the important element of budgeting regulation, i.e. building mechanism of employees’ motivation in budgeting subsystem itself. On the basis of their own experience in the field of enterprise economics and in result of summarizing expert opinions they formulate problems, which should be taken into account in developing budget regulation in the company.
The Essence of Transfer Pricing Mechanism and Risks of International Companies Arising with its Use
Authors: Tsyganova A. I.
Published: April 2023

Today companies, including international ones function in harsh conditions of external instability, thus they try to optimize their financial results in different ways. One of them is mechanism of transfer pricing, which gives an opportunity to redistribute cash flows inside the company and thus to minimize taxes to state and to optimize final finance result. The article discusses the essence of the mechanism of transfer pricing used by international companies and identifies external and internal goals of its use. The author studies legislative base of transfer pricing, analyzes the current methods applied to control deals between interdependent persons, finds their key characteristics and possibility of use. It was found out that transfer pricing is subject to strict control on the part of tax bodies and it can lead to serious finance risks of companies. They are risks arising directly in case mechanism of transfer pricing is used and risks of insufficient, ‘thin’ capitalization. Taking these indicators into account can help forecast and later minimize potential finance risks of the company.
C15-Imines of Natural Matrine Alkaloid as Anti-HIV-1 Agents
Authors: Lv Min , Huang Ning , Jun-Jie Li , Yang Liu-Meng , Zhang Shaoyong , Ma Qianjun , Zheng Yong-Tang , Xu Hui
Published: April 2023

Background:

Human immunodeficiency virus (HIV) infection and acquired immunodeficiency
syndrome (AIDS) have resulted in a global health threat. Meanwhile, due to the emergence of drugresistant
HIV-1 strains, the discovery of potent compounds for antiretroviral therapy success is highly
desirable.

Objective:

This study aimed to develop anti-HIV-1 candidates which can be effectively applied for the
treatment of HIV infection.

Methods:

Based upon our previous results, a series of E isomers of C15-imines of matrine (3a-l) were
semi-synthesized from a natural quinolizidine alkaloid matrine. Their anti-HIV-1 activities were evaluated
against HIV-1ⅢB replication in acutely infected C8166 cells in vitro.

Results:

Derivatives 3c, 3h and 3j showed good anti-HIV-1 activities with EC50 and therapeutic index
(TI) values of 0.0089/0.012/0.0091 mM, and 23.71/32.49/27.43, respectively.

Conclusion:

The substituents and their corresponding positions on the phenyl ring of C15-imine derivatives
of matrine were vital for anti-HIV-1 activities. Compounds 3c, 3h and 3j can be used as leads for
further structural modification as HIV-1 inhibitors.
Is the Patient Actually Failing on Enzalutamide? A Case Report and Issues
to Consider in Enzalutamide-Resistant Oligoprogressive Metastatic
Castrate-Resistant Prostate Cancer
Authors: Papageorgiou Georgios Ioannis , Skouteris Nikolaos , Kosma Aikaterini , Markouizou Athina , Charalampakis Nikolaos
Published: April 2023

Background:

Background: Metastatic castrate-resistant prostate cancer (mCRPC) is a challenging
disease, especially in heavily pretreated patients. Androgen pathway inhibitors have contributed to
a notable improvement in the overall survival and quality of life in patients with mCRPC during the
last decade. Still, a considerable percentage of patients are unable to draw benefits from this drug
category and are deprived of a treatment that offers limited toxicity and preserves a good quality of
life. The mechanisms leading to this pre-existing or acquired resistance, as well as the possible
strategies to overcome this resistance have been put at the center of scientists’ attention.

Case Presentation:

With the present report we present the case of a 70-year-old patient with
mCRPC, who was apparently an enzalutamide non-responder, but a multimodal approach with
enzalutamide continuation and irradiation to his symptomatic oligoprogressive disease converted
him to a responder with clinical, biochemical and imaging response; furthermore, we discuss the
existing data providing evidence for the use of metastasis-directed therapy in combination with
androgen pathway inhibitors in order to overcome drug resistance in patients with oligoprogressive
disease.

Conclusion:

A considerable proportion of patients with oligometastatic or oligoprogressive
prostate cancer who seem not to respond to androgen pathway inhibitors, such as enzalutamide, due
to preexisting or acquired resistance, could benefit from MDT with a multimodal treatment
approach. This strategy allows androgen pathway inhibitor continuation beyond biochemical
progression and delays the switch to next-line systemic treatment.
Mechanical Characteristics and Vibration Control of Railway Signal Relay
Authors: Peng Zhiping , Zhou Shan
Published: April 2023

Introduction:

In order to solve the problems of time-consuming and poor effects of
traditional mechanical vibration control methods for the relay, the mechanical characteristics and
vibration control of railway signal relays are studied in this paper. Based on the analysis of the
mechanical characteristics of railway signal relays, the mechanical characteristic parameters of the
relay, such as contact force, initial pressure, contact clearance, and overtravel are explored. On
this basis, mechanical vibration control is completed based on particle swarm optimization.

Methods:

First, sensors are used to collect the data on the railway signal relay, and the mechanical
vibration control model of the railway signal relay is built. Then, the structure of the PID vibration
controller and LQR vibration controller in the model is analyzed. Finally, the controller parameters
are adjusted through particle swarm optimization to improve the mechanical vibration control
effect of the relay.

Results:

The simulation results show that the average signal-to-noise ratio of the method is 67dB,
the collected data has low noise, and the control time is short, which is 1.4 s.

Conclusion:

The displacement of the railway signal relay controlled by the method is always less
than 0.15 mm, and the control effect is good, which can be widely used in practice.
Exploring the Role of Mentha in Gut Microbiota: A Modern Perspective
of an Ancient Herb
Authors: Arora Swasti , Sharma Alok
Published: April 2023

Gut microbiota includes the microbes present in the gut; these microbes are an essential
component in maintaining a healthy gut. Gut microbiota has a wide range of functions, including
effects on colonization, pathogen resistance, intestinal epithelial maintenance, metabolizing
food and pharmaceutical chemicals, and influencing immunological functions. Every disease
associated with the gut starts due to a disbalance in the composition of the gut microorganisms
and can be managed by balancing the composition of gut bacteria using various herbal remedies.
Mentha herbs are a variety of perennial herbs that are grown commercially in various parts of the
world. Mentha is a potent herb that shows anticholinergic action and can block PGE2 and GM1
receptors and interact with cholera toxins; it is used traditionally in different systems of medicines
to treat various gastrointestinal diseases associated with the gut. Mentha herbs have potent
bactericidal, viricidal, and fungicidal properties. Mentha has been used to cure stomach and digestion
issues as well as to treat a variety of disorders. This review article summarizes diseases
associated with the gut, the composition, and function of gut microbiota, and mentha's effectiveness
along with its extraction methods and traditional uses. Research findings revealed that mentha
could be an essential source against a wide range of diseases, especially gastrointestinal disorders.
From its ayurvedic claims to its present use, various confirmed its clinically effective for
human health. The present work also describes the mechanism of action along with the bioactives
present in this well-known herb from Ayurveda.
Design and evaluation of liquid channel cross sections fabricated via metal fused filament fabrication
Authors: BACIKOGLU M.C.
Published: April 2023

Abstract. Metal Fused Filament Fabrication is an Additive Manufacturing method of manufacturing metal parts by using filaments composed of metal powders encased in plastic binders. It is advantageous for manufacturing parts with complex geometries using a wide range of materials, including stainless steel, copper, tool steel, nickel alloys, and titanium. When support structures are not required, complex parts with interior cavities can be produced using this method. In this study, interior channel cross sections for cold plates, the main elements in cooling high-power electronic units, are designed and fabricated without the use of support structures. Specimens are made of 17-4 PH stainless steel and copper using the method with two different systems. Straight and angled interior channels are fabricated separately to investigate the characteristics of supportless manufacturing and observe the sagging or warping effects on the liquid channel faces. Surface roughness and Coordinate Measuring Machine measurements are performed for parts to check if the quality requirements are fulfilled in terms of shrinkage and assembly. Density is determined for parts using the Archimedes method and compared with the porosity results obtained from Scanning Electron Microscope.
Hot stamping of ultra-thin stainless steel for microchannels
Authors: GUO N.
Published: April 2023

Abstract. Bipolar plate is one of the core components of a proton exchange membrane fuel cell (PEMFC), in which microchannels with regular distribution separate and distribute the fuel gas at the anode and oxygen/air at the cathode, and remove the reaction products from the cell. Dimensional deviations of microchannels affect assembly accuracy, thereby influencing the efficiency and performance of PEMFC. Ultra-thin stainless steel sheet is the most commonly used material for bipolar plate and stamping is an efficient way to form stainless steel microchannels. However, a challenge faced by the stamping process is how to improve the dimensional accuracy of stainless steel microchannels. Hereby we propose a hot stamping process of ultra-thin stainless steel sheet, which is of high potential to improve the dimensional accuracy of micro-channels. Uniaxial tensile tests are performed at room temperature (RT), 300, 600, and 900°C for an ultra-thin stainless steel 316L (SS316L). Results show that the strength of SS316L at 900 °C decreases significantly compared with that at RT, while the elongation is approximately 44%. Hot stamping process for stainless steel microchannels is developed, in which the ultra-thin sheet is heated by resistance heating. Stainless steel microchannels are hot stamped at 900°C, and the 3D profile and cross-sectional thickness distribution of which are measured. The measurement results show that the dimensional deviations of hot-stamped microchannels are lower than that of cold stamping, in terms of channel depth, rib width, and wall angle. Furthermore, the cross-sectional thickness distribution of the hot-stamped micro-channels has a similar trend as that of the cold stamping, and the thickness at the fillet is not significantly different (avg. + 1 μm) from that of the cold stamping.
Influence of surface pressure and tool materials on contact heating of aluminum
Authors: Tran R.
Published: April 2023

Abstract. The implementation of lightweight design concepts can significantly benefit from using highly efficient heating technologies such as contact heating in thermo-mechanical processing of sheet metal components. The investigation of the influence of surface pressure and tool material on the heating time and the heating rate during contact heating is the subject of this publication. A specially manufactured contact heating tool with comprehensive temperature and force measurement was used for studying the effects of different contact plate materials (CuZn39Pb3 and CuCr1Zr), surface pressures (3 MPa - 15 MPa) and variable plate thicknesses (1.0 mm - 5.2 mm) during heating of the aluminum alloy EN AW-7075 up to the solution heat treatment temperature of 475 °C. It was observed that heating time is lower for thinner workpieces. Furthermore, heating times decrease and heating rates increase significantly with increasing surface pressure for a pressure range of 3 MPa - 9 MPa. A further increase in surface pressure is not recommended, because the benefit in terms of further reduction of the heating time is marginal and the strength of the contact plate materials at elevated temperatures is limited. Contact heating using copper plates is significantly faster compared to brass plates and the conventionally used steel plates. Brass plates, however, benefit more from an increase in surface pressure. Both investigated materials allow faster heating than conventional steel plates due to their higher thermal conductivity. Depending on the specific process parameters the heating process can be accelerated to less than one second. Thus, contact heating can be realized within the press cycle.
Low-cost tooling concept for customized tube bending by the use of additive manufacturing
Authors: TRONVOLL S.A.
Published: April 2023

Abstract. Bending is commonly used in the manufacturing of finished and semi-finished, profile-based products. However, costly profile and bend geometry dependent tooling hampers its applicability for low volume production or prototyping. Additive manufacturing (AM) offers a potential for making tools in low-volume production, which is particularly attractive for customized manufacturing and prototyping with near production intent tooling. In this research, an industrial bending process for tubes and profiles, called rotary drawing bending (RDB), is used as a case. In the RDB process, the mandrel die installed inside the tube or profile blank is of crucial importance to secure the quality of the cross-section of bent shapes. Moreover, this die is normally difficult and expensive to produce. In addition, each mandrel is tailored to a single profile’s inner geometry, hence posing an obstacle to acquiring a tooling setup for multiple cross-section dimensions. As a countermeasure, a novel mandrel tooling concept is designed by using a metal rod core with an AM-sleeve fitted to the rod outside, as an easy-to-replicate solution for significantly lowering the costs of offering the capability of forming processes with different cross-section dimensions. Fused filament fabrication (FFF)—a cost-effective AM process—is used for fabricating the mandrel die with various pre-designed and optimized shapes. Using both the AM mandrel in polylactide (PLA) and the conventional metal mandrel in a series of bending experiments of AA6082-T4 Al-alloy tubes, the dimensional and qualitative results of tubes bent with different mandrels is analyzed, discussed, and compared.
Clinching with divided punch to prevent critical neck thicknesses
Authors: FALK T.
Published: April 2023

Abstract. Clinching thin sheet metal into a thicker part can result in low neck thicknesses or even neck cracks. How these critical low values for neck thickness can be counteracted is described in this paper, using a two-part punch, which is devided in an inner and outer unit. At the beginning, both move parallel in the direction of the die until the outer punch stops at a defined position and only the inner one moves further down and forms the clinch point, with its characteristic contour and the geometric values of interlock and neck thickness. Due to the large punch diameter at the beginning of the process, more material initially flows into the neck area than in conventional clinching, so that a greater neck thickness can be achieved. Numerical simulation was used to create the concept and verify it experimentally. The greater neck thickness has a positive effect on the shear tensile strength and can also be transferred to the typical joining direction for clinching (thick into thin material).
FSW process mechanics and resulting properties for dissimilar Al-Ti T-joints
Authors: RANA H.
Published: April 2023

Abstract. Emergent manufacturing demands for superior performance but lightweight structures have pinpointed the development of multi-material and hybrid structures specifically in the aerospace and automotive industrial sectors. Friction stir welding (FSW), a solid-state joining technique has been proven very effective to produce joints between materials possessing extremely diverse thermal and mechanical properties. The present research aims to investigate the feasibility of Al-Ti skin-stringer joints with different plate geometries and placements. The effect of different approaches on material flow, grain morphology, intermittent phases, joint resistance, and microhardness are discussed in depth.
Versatile self-piercing riveting with a tumbling superimposed punch
Authors: Wituschek S.
Published: April 2023

Abstract. Increasing resource efficiency is a major challenge and affects almost every aspect of social and economic life. The mobility sector in particular is responsible for a large share of primary energy consumption and is increasingly in the focus of public interest. One possibility to adress these challenges is to reduce the vehicle weight by means of lightweight construction technologies such as multi-material systems. These assemblies consist of workpieces with different mechanical and geometrical properties, which poses a major challenge for joining technology. Mechanical joining processes such as semi-tubular self-piercing riveting are often used in the production of these assemblies, but due to their process characteristics, they are rigid and can only react to changing process variables to a limited extent. One way to increase the versatility of self-piercing riveting is to superimpose a tumbling kinematics on the punch. During tumbling, an angular offset of the punch axis to the tool axis is set and the contact area between punch and workpiece is reduced. In this work, investigations were carried out to determine how the tumbling strategy, consisting of the parameters tumbling angle, tumbling onset and tumbling kinematics, affects the material flow of the rivet element. For this purpose, experimental tests are conducted with the typical materials of conventional multi-material systems and the geometric joint formations are determined by means of macrographs.
Identification of the large strain flow curve of high strength steel via the torsion test and FEMU
Authors: VANCRAEYNEST N.
Published: April 2023

Abstract. A torsion specimen is removed from the as-received thick high strength steel sheet (S700MC with a nominal thickness of 12 mm). The test material has a maximum uniform tensile strain of about 12 %. The torsion test is conducted up to fracture. The experimentally acquired torque-angle curve is then used to inversely identify the large strain flow curve up to an equivalent plastic strain of approximately 1. The identification strategy is based on the Finite Element Model Updating (FEMU) approach.
Coupling machine learning and synthetic image DIC-based techniques for the calibration of elastoplastic constitutive models
Authors: PRATES P.A.
Published: April 2023

Abstract. Today, most design tasks are based on simulation tools. However, the success of the simulation depends on the accurate calibration of constitutive models. Inverse-based calibration methods, such as the Finite Element Model Updating and the Virtual Fields Method, have been developed for identifying constitutive parameters. These methods are based on mechanical tests that allow heterogeneous strain fields under the “Material Testing 2.0” paradigm in which digital image correlation plays a vital role. Although these methods have been proven effective, constitutive model calibration is still a complex task. A machine learning approach is developed and implemented to calibrate elastoplastic constitutive models for metal sheets, using datasets populated with finite element simulation results of strain field data from mechanical tests. Feature importance analysis is conducted to understand the importance of the different input features and to reduce the computational cost related with model training. Synthetic image DIC-based techniques were coupled with the numerically generated database, enabling the construction of a virtual experiments database that accounts for sources of uncertainty that can influence experimental DIC measurements. A robustness analysis of the methodology is performed for the boundary conditions of the test.
Machining of PAM green Y-TZP: Influence of build and in-plane directions on cutting forces and surface topography
Authors: SPITAELS L.
Published: April 2023

Abstract. The combination of the pellet additive manufacturing (PAM) process and green ceramic machining within the same hybrid machine is a very promising route to obtain green ceramic parts with complex shapes, smooth surface topography and tight tolerances. However, there is still a lack of data due to the novelty of this manufacturing route. This article studies the possible influence of the build and in-plane directions on the cutting forces and surface topography during the milling of Y-TZP green ceramic parts obtained by the PAM process. The RMS cutting forces, arithmetic and total roughness (Ra and Rt, respectively) were measured. The in-plane direction (aligned with one of the horizontal part edges) did not have a significant influence neither on the cutting forces nor on the surface topography. Conversely, the build direction has a significant effect on the cutting forces recorded. The layers deposited the furthest from the build platform required 57.5% less force to be milled than those in contact with it. The surface topography was not significantly modified across the build direction, all values of Ra were within the 0.8 µm Ra class while all Rt values were < 5 µm.
Evaluation of the surface integrity characteristics of internal threads machined on lead-free brass alloy
Authors: ZOGHIPOUR N.
Published: April 2023

Abstract. Tapping is a typical machining method being utilized in manufacturing internal threads. However, it contains few difficulties to be dealt with since during the process, many cutting edges involve synchronized axial and rotational movements. This work presents the results of an experimental study on the material type considering the influences of the manufacturing process (extrusion and forging) and tap type on the surface integrity characteristics of lead-free brass alloys. Experimental data on the surface quality of the threads, subsurface characteristics including microhardness is presented and analyzed. This study demonstrates that the manufacturing methods have a robust effect on microstructural aspects of low-lead brass alloy and resulting in hardening of the surface and subsurface.
Analytical method for determining cutting forces during orthogonal turning of C45 steel
Authors: ŚLUSARCZYK L.
Published: April 2023

Abstract. The authors present a method for determining cutting forces during orthogonal turning of C45 steel. The method utilizes Oxley’s chip formation model as well as Johnson-Cook (J-C) constitutive equation and is based on the assumption that the tool is perfectly sharp and the chip formation process is continuous. It is also assumed that the heat exchange between the workpiece, the tool and the chip is carried out by conduction with negligibly small loses caused by convection and radiation and that the thickness of the chip contacting the rake face is constant. The adoption of the above assumptions, together with the knowledge of cutting parameters (including the tool rake angle) as well as of material constants of J-C equation, allows to estimate the thermal-mechanical state of the cutting process and to determine feed and tangential components of the cutting force. Average values of feed and tangent components of the cutting force are calculated using an algorithm implemented in the Matlab environment. The method is based on iterative determination of the minimum difference between stress values in the secondary shear zone. Considered tangential and normal stress values are expressed by formulas based on Oxley's cutting mechanics and the J-C model. The cutting force components obtained in the described method have been compared with the results obtained during experimental studies and with the results obtained in computer simulations using the FEM numerical calculation method.
Novel methodology for burr extension estimation on machined SLM surfaces
Authors: GINESTRA P.
Published: April 2023

Abstract. Additive manufacturing techniques can cover the needs of these components thanks to their high level of customization of the products and the ability to realize complex shapes without high effort. Despite the benefits derived from AM processes, these techniques are characterized by a low-quality of surface finish, one of the most important requirements for medical devices. Considering this aspect, it is important to develop a solution able to improve the surface finish in order to enjoy the low lead times and the high level of customization typical of these processes. A characteristic element of micro-machining is the presence of burrs on the machined surface which can affect the surface texture of micro-features. For this reason, a novel technique for the evaluation of burr was defined. The burrs were evaluated by means of an autofocus variation digital microscope Keyence VHX-7100, on 17-4 PH steel samples produced by laser bed fusion. A 3D reconstruction of the channels and holes surfaces was performed and through the analysis of the peaks distribution, a threshold was defined to discriminate between the original surface of the part and the burrs. In this way, it was possible to estimate and approximate the value of the extension of the burrs in terms of volume and area, where the area is referred to the projected area. Specifically, in micro-machining, not only the extension of the burrs is significant, but also the variability is particularly high, preventing a priori consideration of the defect.
Simple multiaxial tests to assess dynamic ductility of 17-4PH
Authors: MANCINI E.
Published: April 2023

Abstract. To investigate material ductility, the use of simple multiaxial specimens which can be tested through a common tensile machine or by a Split Hopkinson bar facility would allow avoiding the use of more complex equipment to induce different stress states in the investigated material. In this work, experimental dynamic tests have been performed on four different specimen geometries on a 17-4PH steel by a direct Split Hopkinson Bar (SHB). Finite element models of the experiments are set up and used jointly with experimental data to calibrate and validate a strain rate dependent plasticity model, and to extract the local values of stress and ultimate strain in the most critical point of the samples, at fracture. These latter results allowed the calibration of a ductile damage model, whose predictions, compared with a previous calibration using tests carried out in quasi-static conditions, confirmed the effectiveness of the proposed specimens and test methodology to assess material ductility under dynamic conditions.
Nonlinear elastic stress triaxiality dependent constitutive model for fibre-reinforced polymer composites
Authors: OBID S.
Published: April 2023

Abstract. A novel constitutive model is proposed to describe fibre-reinforced polymer composite materials. The model covers three fundamental phenomena of such materials: anisotropy, tension-compression asymmetry, and nonlinear material behaviour. The model is based on the one-dimensional Ramberg-Osgood relation, which is extended to a multiaxial anisotropic form. Tension-compression asymmetry is then implemented with the introduction of stress triaxiality dependency. Finally, the model is verified using experimental data where the material response in uniaxial tension, uniaxial compression and shear stress states were measured.
Extension of the modified Mohr-Coulomb fracture model by a strain rate and temperature dependence
Authors: VASQUEZ RAMIREZ D.
Published: April 2023

Abstract. During industrial sheet metal processes such as shear cutting, high temperatures and strain rates occur. Due to materials dependency on temperature and strain rate, the numerical fracture modelling should consider these both highly influential factors for accurate simulation results. Since the widely used Modified Mohr-Coulomb (MMC) fracture model does not take the dependency on temperature and strain rate into account, the objective of this research is therefore to extend the MMC fracture model. For the fracture characterization, miniaturised tensile tests under variation of specimen geometry, temperature and strain rate are conducted. Additionally, tensile tests with butterfly specimens under varying stress states are carried out. In order to determine material specific MMC parameters, the experimental tests are numerically depicted in Abaqus. The temperature and strain rate extension of the MMC fracture model is based on the Johnson-Cook failure model. With this approach, a temperature and strain-rate dependent MMC fracture model is developed for the dual phase steel DP980.
Local and nonlocal strain gradient approaches for size-dependent plastic deformation
Authors: ÜNSAL I.E.
Published: April 2023

Abstract. Micro scale manufacturing technologies have been a productive area of research due to the increase in miniaturization in various industries. However, most of the know-how in conventional metal forming processes cannot be readily transferred into micro/meso forming processes due to the size effect. By incorporating the length scale into the formulation, strain gradient theories offer a viable solution to the issues arising from size-dependent complications. This paper aims at implementing a lower-order strain gradient plasticity (SGP) theory developed from the Taylor dislocation model to numerically analyze the impact of the plastic size effect on the forming of metallic materials. The material model together with local and nonlocal approaches for the strain gradient calculations is implemented in a commercial finite element (FE) code through user subroutines. The flat punch indentation problem is examined using the implemented code.
Evaluation of data transfer methods efficiency in the random cellular automata model of dynamic recrystallisation
Authors: PAWLIKOWSKI K.
Published: April 2023

Abstract. Numerical simulations can help predict microstructure morphology evolution under hot forming conditions and support final material properties determination. Cellular Automata (CA) is a commonly used full-field method to model changes in microstructure morphology during different metal-forming processes. However, in the case of microstructure evolution changes during high deformation levels, at higher temperatures, the CA method has some limitations related to computational domain geometry changes. The use of random cellular automata (RCA) allows for a more realistic representation of this phenomenon. However, it involves much more effort during model implementation to optimise the algorithm in terms of execution time, which has to be at an acceptable time. This paper is a part of a larger research aiming at developing the dynamic recrystallisation model (DRX) using the RCA directly incorporated into the finite element (FE) framework. The main goal of the current work is to evaluate the efficiency of data transfer approaches between the two mentioned coupled model components. Particular attention is on shortening the execution time thanks to data streams opened in binary mode.
Visual quality prediction of plastic product based on thermographic images
Authors: LE GOFF R.
Published: April 2023

Abstract. The main purpose of this study is to control the visual quality in plastic injection moulding using an infrared camera after the ejection of the plastic part. Quality indicators have been extracted from the thermal image and from the data recorded by the sensors in the plastic injection machine and in the mould. After cooling, visual quality has been labelled by plastic experts based on 3 aesthetic defects: spot, flow line and streak mark. Three methods of reducing the dimension of the thermal image were studied: Quantiles, Principal Component Analysis (PCA), and Linear Discriminant Analysis (LDA). The visual quality can be predicted efficiently using dimension reduction of the image and Partial Least Square (PLS) regression. The PLS results allow to identify the root causes that explain the apparition of visual defects.
A meshless numerical solution of thermo-mechanics of hot-rolled steel bars on a cooling bed
Authors: VUGA G.
Published: April 2023

Abstract. After the continuous hot-rolling process, steel bars are immediately placed on the cooling bed. At the beginning of the cooling, the material is at high temperatures, and the yield strength is low. Due to thermal load, yield strength can be exceeded, and permanent plastic strains start accumulating, resulting in possible unwanted shape changes and residual stresses. The present paper aims to develop a thermo-mechanical model for studying and eliminating undesirable phenomena before the products leave the cooling bed. The governing equations are solved for the two-dimensional slice in a strong form, and a modified version of the radial basis function generated finite difference (RBF-FD) method [1]. The initial bar geometry is obtained from the existing meshless hot-rolling simulation system [2]. The thermal and mechanical models are one-way coupled, i.e. the temperature solution represents a driving force for the stress and strain solution. The temperature field is obtained with explicit propagation in time. The convective and radiative heat fluxes on the boundary are updated at each time step using the ray tracing procedure to determine the radiative heat flux. The mechanical part is solved by considering the small strain elasto-plasticity, where the isotropic von Mises temperature-dependent hardening is employed. The global system of nonlinear equations of the mechanical part is solved by the Newton-Raphson method. The closest point projection method is used to solve the constitutive relations. A sensitivity study is performed on the influence of cooling intensity on a rectangular steel bar’s temperature, stress and strain field. We defined the most influential factors for defect formation. For the first time, a novel meshless RBF-FD method is successfully used for solving such a complex industrial problem. The model will be perspectively upgraded from the slice to the three-dimensional model to enable also bending.
Design of a user-friendly human machine interface for jet electrochemical machining
Authors: DAMM P.
Published: April 2023

Abstract. Electrochemical machining with a closed free jet (Jet-ECM) is a flexible ablating manufacturing technology. With this manufacturing technology, surface structures in the micrometer range can be generated without tool wear occurring. Until now, the technology has mainly been developed in research institutions. Therefore, the aspect of a user-friendly human machine interface has not been in the focus of the machine tool design. The aspect of a user-friendly human machine interface was considered in the construction and development of a new Jet-ECM prototype system at the Otto von Guericke University Magdeburg (OVGU). The prototype system is intended for teaching and research purposes. Users, who will operate the prototype system, have different knowledge of the Jet-ECM process and machine control. Therefore, it was necessary to develop a user-friendly interface, that is easy to learn and easy to use.In the present study, the procedure for creating a user-friendly human-machine interface will be introduced, and the resulting design will be explained. The design was developed according to established design guidelines for machine systems and can also serve as a template for industrial operation. To arrange the operating elements ergonomically and according to the material, energy and information flow, a suitable mask layout was developed. Furthermore, the user interface is suitable for future expansion. Based on the realised user interface, the main components of the Jet-ECM prototype system can be controlled, various process functions can be executed, and different process variables can be analysed.