Hasil untuk "Production capacity. Manufacturing capacity"

Ablie Njie, Tobias Hüsemann, Bernhard Karpuschewski

The use of metalworking fluid (MWF) in surface grinding is essential, but its supply contributes notably to the process energy demand. This study investigates the effect of the fluid jet to wheel speed ratio <i>q</i>_s on specific grinding energy and associated CO₂ emissions. Experiments with grinding wheels of different grit sizes (F60–F120) were conducted at cutting speeds of 35 and 60 m/s. Critical specific material removal rates <i>Q</i>’_{w, crit} were determined by taper grinding, with the onset of grinding burn identified by Barkhausen noise analysis. Based on these values and the grinding wheel width, specific process energies <i>e</i>_total were derived from grinding, pump, and machine base load. F120 wheels showed no systematic dependence of <i>Q</i>’_{w, crit} on <i>q</i>_s, whereas for coarser F80 and F60 wheels, decreasing <i>q</i>_s from 1.0 to 0.6 increased <i>Q</i>’_{w, crit} by 13–27% at 35 m/s and decreased it by 33–35% at 60 m/s. The most efficient process (F60, 35 m/s, <i>q</i>_s = 0.6) required 152.8 J/mm³, the least efficient (F120, 60 m/s, <i>q</i>_s = 0.8) 333.1 J/mm³. Because CO₂ emissions scale with <i>e</i>_total, the relative differences in energy directly indicate relative differences in CO₂ output. An illustrative case study shows that adjusting <i>q</i>_s alone (F80, 35 m/s) lowers annual emissions from 0.284 t to 0.206 t, a reduction of approximately 27%. These findings highlight the influence of <i>q</i>_s on grinding efficiency and process energy demand.

M. D. Urmey, S. Dickson, K. Adachi et al.

A microwave-optical transducer of sufficiently low noise and high signal transfer rate would allow entanglement to be distributed between superconducting quantum processors reliably within the lifetimes of their quantum memories. To clarify the multifaceted performance required for such a task, we derive a broadband quantum channel capacity that bounds the maximum rate at which quantum information can be sent through realistic finite-bandwidth thermal-loss channels. This capacity serves as a comprehensive measure of transducer performance and provides insight into the relative importance of disparate metrics. We find that the broadband capacity depends on the throughput -- defined as the product of efficiency, bandwidth, and duty cycle -- and on the added noise. We present measurements of a membrane-based opto-electromechanical transducer with high throughput of 7 kHz and at an input-referred added noise of 3 photons in both upconversion and downconversion, demonstrating that bidirectional transducer capacities comparable to superconducting qubit decay rates are within reach. In downconversion, throughput of this magnitude at the few-photon noise level is unprecedented, marking an improvement of nearly four orders of magnitude over previous work.

Inés Pérez-Gonzalo, Florentino Alvarez-Antolin, Alejandro González-Pociño et al.

This study investigates the mechanical, tribological, and electrochemical behaviour of a novel precipitation-hardenable martensitic alloy produced by selective laser melting (SLM). The alloy was specifically engineered with an optimised composition, free from cobalt and molybdenum, and featuring reduced nickel content (7 wt.%) and 8 wt.% chromium. It has been developed as a cost-effective and sustainable alternative to conventional maraging steels, while maintaining high mechanical strength and a refined microstructure tailored to the steep thermal gradients inherent to the SLM process. Several ageing heat treatments were assessed to evaluate their influence on microstructure, hardness, tensile strength, retained austenite content, dislocation density, as well as wear behaviour (pin-on-disc test) and corrosion resistance (polarisation curves in 3.5%NaCl). The results indicate that ageing at 540 °C for 2 h offers an optimal combination of hardness (550–560 HV), tensile strength (~1700 MPa), microstructural stability, and wear resistance, with a 90% improvement compared to the as-built condition. In contrast, ageing at 600 °C for 1 h enhances ductility and corrosion resistance (Rp = 462.2 kΩ; Ecorr = –111.8 mV), at the expense of a higher fraction of reverted austenite (~34%) and reduced hardness (450 HV). This study demonstrates that the mechanical, surface, and electrochemical performance of this novel SLM-produced alloy can be effectively tailored through controlled thermal treatments, offering promising opportunities for demanding applications requiring a customised balance of strength, durability, and corrosion behaviour.

Jozef Jaroslav Fekiač, Lucia Kakošová, Michal Krbata et al.

Additive manufacturing of polymer composites, also known as 3D printing, is one of the progressive technologies in material engineering. It enables the production of parts with complex geometries while optimizing material efficiency. Polylactide (PLA) is a widely used material in additive manufacturing due to its biodegradability and suitable mechanical properties. However, its brittleness and limited thermal stability require further modifications, such as modifying the filler structure or adding reinforcing materials. This paper focuses on analyzing the influence of different filler geometries and densities on the mechanical properties of PLA parts manufactured by the fused filament deposition (FFF) method. Three basic filler structures—cubic, gyroid and rectilinear—were investigated at different density levels from 20%, 40%, 60% and 80%. Experimental tests were performed according to ASTM D638 to determine the strength characteristics of the material. In addition to mechanical tests, dynamic mechanical analysis (DMA) and thermogravimetric analysis (TG) were performed to better understand the influence of the filling geometry on the thermal stability and viscoelastic behavior of the material. Experimental tests according to ASTM D638 showed that higher filling density improves mechanical properties. At 80% filling, the tensile strength reached 21.06 MPa (cubic), 20.53 MPa (gyroid) and 20.84 MPa (linear). The elastic modulus was highest with cubic filling (1414.19 MPa). The yield strength reached 15.59 MPa (cubic), 15.52 MPa (gyroid) and 14.30 MPa (linear).

Qi Cao, Yulin Shao, Shangwei Ge

This paper investigates the zero-error capacity of channels with memory. Motivated by the nuanced requirements of semantic communication that incorporate memory, we advance the classical enlightened dictator channel by introducing a new category known as the semantic channel. We analyze the zero-error capacity of the semantic channel using a comprehensive framework that accommodates multiple input and output memories. Our approach reveals a more sophisticated and detailed model compared to the classical memory channels, highlighting the impact of memory on achieving error-free communication.

Diana Popescu, Mariana Cristiana Iacob, Cristian Tarbă et al.

This article proposes the integration of two novel aspects into the production of 3D-printed customized wrist-hand orthoses. One aspect involves the material, particularly Colorfabb varioShore thermoplastic polyurethane (TPU) filament with an active foaming agent, which allows adjusting the 3D-printed orthoses’ mechanical properties via process parameters such as printing temperature. Consequently, within the same printing process, by using a single extrusion nozzle, orthoses with varying stiffness levels can be produced, aiming at both immobilization rigidity and skin-comfortable softness. This capability is harnessed by 3D-printing the orthosis in a flat shape via material extrusion-based additive manufacturing, which represents the other novel aspect. Subsequently, the orthosis conforms to the user’s upper limb shape after secure attachment, or by thermoforming in the case of a bi-material solution. A dedicated design web app, which relies on key patient hand measurement input, is also proposed, differing from the 3D scanning and modeling approach that requires engineering expertise and 3D scan data processing. The evaluation of varioShore TPU orthoses with diverse designs was conducted considering printing time, cost, maximum flexion angle, comfort, and perceived wrist stability as criteria. As some of the produced TPU orthoses lacked the necessary stiffness around the wrist or did not properly fit the palm shape, bi-material orthoses including polylactic acid (PLA) inserts of varying sizes were 3D-printed and assessed, showing an improved stiffness around the wrist and a better hand shape conformity. The findings demonstrated the potential of this innovative approach in creating bi-material upper limb orthoses, capitalizing on various characteristics such as varioShore properties, PLA thermoforming capabilities, and the design flexibility provided by additive manufacturing technology.

Fabio Giudice, Severino Missori, Andrea Sili

Dissimilar welds between ferritic and austenitic stainless steels are widely used in industrial applications. Taking into account the issues inherent to arc welding, such as the high heat input and the need to carry out multiple passes in the case of thick plates, a procedure with two simultaneous laser beams (working in a single pass) and consumable inserts as filler metal has been considered. Particular attention was paid to the choice of the filler metal (composition and amount), as well as welding parameters, which are crucial to obtain the right dilution necessary for a correct chemical composition in the weld zone. The first experimental investigations confirmed the achievement of a good weldability of the dissimilar pair ASTM A387 ferritic/AISI 304L austenitic steel, having ascertained that the microstructure of the weld zone is austenitic with a little amount of residual primary ferrite, which is the best condition to minimize the risk of hot cracking.

Liaoyuan Wang, Yuli Sun, Zhongmin Xiao et al.

With the rapid development of high-end manufacturing industries such as aerospace and national defense, the demand for metal additive manufactured parts with complex internal cavities has been steadily increasing. However, the finishing of complex internal surfaces, especially for irregularly shaped parts, remains a significant challenge due to their intricate geometries. Through a comparative analysis of common finishing methods, the distinctive characteristics and applicability of magnetic abrasive finishing (MAF) are highlighted. To meet the finishing needs of complex metal additive manufactured parts, this paper reviews the current research on magnetic abrasive finishing devices, processing mechanisms, the development of magnetic abrasives, and the MAF processes for intricate internal cavities. Future development trends in MAF for complex internal cavities in additive manufactured parts are also explored; these are (1) investigating multi-technology composite magnetic abrasive finishing equipment designed for complex internal surfaces; (2) studying the dynamic behavior of multiple magnetic abrasive particles in complex cavities and their material removal mechanisms; (3) developing high-performance magnetic abrasives suitable for demanding conditions; and (4) exploring the MAF process for intricate internal surfaces.

Max Hossfeld, Arnold Wright

Additive friction extrusion deposition (AFED) is a recently developed additive manufacturing technique that promises high deposition rates at low forces. Due to the novelty of the process, the underlying phenomena and their interactions are not fully understood, and in particular, the processing strategy and tool design are still in their infancy. This work contributes to the state-of-the-art of AFED through a comprehensive analysis of its working principles and an experimental program, including a representative sample component. The working principle and process mechanics of AFED are broken down into their individual components. The forces and their origins and effects on the process are described, and measures of process efficiency and theoretical minimum energy consumption are derived. Three geometrical features of the extrusion die were identified as most relevant to the active material flow, process forces, and deposition quality: the topography of the inner and outer circular surfaces and the geometry of its extrusion channels. Based on this, the experimental program investigated seven different tool designs in terms of efficiency, force reduction, and throughput. The experiments using AA 6061-T6 as feedstock show that AFED is capable of both high material throughput (close to 550 mm³/s) and reduced substrate forces, for example, the forces for a run at 100 mm³/s remained continuously below 500 N and for a run at 400 mm³/s below 3500 N. The material flow and microstructure of AFED were assessed from macro-sections. Significant differences were found between the advancing and retracting sides for both process effects and material flow. Banded structures in the microstructure show strong similarities to other solid-state processes. The manufacturing of the sample components demonstrates that AFED is already capable of producing industrial-grade components. In mechanical tests, interlayer bonding defects resulted in more brittle failure behavior in the build direction of the structure, whereas in the horizontal direction, mechanical properties corresponding to a T4 temper were achieved.

Ning Qi, Peng Li, Lin Cheng et al.

Energy storage (ES) and virtual energy storage (VES) are key components to realizing power system decarbonization. Although ES and VES have been proven to deliver various types of grid services, little work has so far provided a systematical framework for quantifying their adequacy contribution and credible capacity value while incorporating human and market behavior. Therefore, this manuscript proposed a novel evaluation framework to evaluate the capacity credit (CC) of ES and VES. To address the system capacity inadequacy and market behavior of storage, a two-stage coordinated dispatch is proposed to achieve the trade-off between day-ahead self-energy management of resources and efficient adjustment to real-time failures. And we further modeled the human behavior with storage operations and incorporate two types of decision-independent uncertainties (DIUs) (operate state and self-consumption) and one type of decision-dependent uncertainty (DDUs) (available capacity) into the proposed dispatch. Furthermore, novel reliability and CC indices (e.g., equivalent physical storage capacity (EPSC)) are introduced to evaluate the practical and theoretical adequacy contribution of ES and VES, as well as the ability to displace generation and physical storage while maintaining equivalent system adequacy. Exhaustive case studies based on the IEEE RTS-79 system and real-world data verify the significant consequence (10%-70% overestimated CC) of overlooking DIUs and DDUs in the previous works, while the proposed method outperforms other and can generate a credible and realistic result. Finally, we investigate key factors affecting the adequacy contribution of ES and VES, and reasonable suggestions are provided for better flexibility utilization of ES and VES in decarbonized power system.

Xavier Guidetti, Efe C. Balta, Yannick Nagel et al.

When manufacturing parts using material extrusion additive manufacturing and anisotropic polymers, the mechanical properties of a manufactured component are strongly dependent on the print trajectory orientation. We conduct non-planar slicing and optimize the print trajectories to maximize the alignment between the material deposition direction and the stress flow induced by a predefined load case. The trajectory optimization framework considers manufacturability constraints in the form of uniform layer height and line spacing. We demonstrate the method by manufacturing a load bearing mechanical bracket using a 5-axis 3D printer and a liquid crystal polymer material. The failure strength and stiffness of the optimized bracket are improved by a factor of 44 and 6 respectively when compared with conventional printing.

Lana Jarža, Anka Ozana Čavlović, Stjepan Pervan et al.

This paper deals with an overview of additive manufacturing and its segment - 3D printing, which is today rapidly and widely used (Agashe et al., 2020) for personal and high-capacity production. The paper discusses the possible positive factors such as small and personalized production series, cheaper design and production process, complex geometry, bionic structures (whose surfaces are complicated to make, and are copy of biological organisms) and negative factors such as lack of educated specialists and trainings. Those facts are affecting the implementation of these technologies in different segments of the design, product development and furniture production. The impacts of new technologies on the design and production of rapid prototypes and finished products in furniture industry are analyzed. The positive results of using additive manufacturing indicate that, in spite of minor obstacles and problems with connecting different production processes, additive production will have a significant place in the future of furniture design and production. The most important advantages of 3D printing is fast prototyping, one piece production, free form designing and the use of bio-based materials and their possibility of recycling.

Anju Pokharel, Randhir Kumar Jaidka, N. U. Sruthi et al.

White salted (udon) noodles are one of the major staple foods in Asian countries, particularly in Japan. Noodle manufacturers prefer the Australian noodle wheat (ANW) varieties to produce high-quality udon noodles. However, the production of this variety has reduced significantly in recent years, thus affecting the Japanese noodle market. Noodle manufacturers often add tapioca starch to compensate for the flour scarcity; however, the noodle-eating quality and texture are significantly reduced. This study, therefore, investigated the effect of the addition of porous tapioca starch on the cooking quality and texture of udon noodles. For this, tapioca starch was initially subjected to enzyme treatment, ultrasonication, and a combination of both to produce a porous starch where a combined enzyme (0.4% alpha amylase)–ultrasound treatment (20 kHz) yielded a porous starch with increased specific surface area and better absorbent properties which are ideal for udon noodle manufacturing, Later, udon noodles were prepared using three varieties of ANW, a hard Mace variety, and commercial wheat flour by incorporating the prepared porous tapioca starch at a concentration of 5% and 10% of dry ingredients. Adding this porous starch resulted in a lower cooking time with higher water absorption and desirable lower cooking loss compared to the control sample with 5% of the porous starch chosen as the optimum formulation. Increasing the level of the porous starch reduced the hardness of the noodles whilst maintaining the desired instrumental texture. Additionally, a multivariate analysis indicated a good correlation between responses’ optimum cooking time and water absorption capacity as well as turbidity and cooking loss, and a cluster analysis grouped noodle samples prepared from different varieties into the same clusters based on the porous starch added, indicating the possibility of different market strategies to improve the quality of the udon noodles produced from different wheat varieties.

Shahzaib Ashraf, Shahzad Noor Abbasi, Muhammad Naeem et al.

The main objective of this study is to identify the green suppliers that would most effectively assist manufacturing producers in implementing green manufacturing production while including uncertainty and reliability in their decision-making. For this firstly, we justify and manifest the idea of Pythagorean Fuzzy Z-numbers (PyFZNs). It has significant implications for improving the effectiveness of decision-making processes in several theories of uncertainty. It can more flexibly explain real-world data and human cognition due to its capacity to express imprecise and reliable information. Thus it is a more accurate mathematical tool for addressing accuracy and uncertainty. Secondly, we defined the Pythagorean fuzzy Z-number arithmetic aggregation operators and geometric aggregation operators. Thirdly, based on the proposed operators and EDAS (Evaluation based on distance from average solution) approach, a fast decision model is designed to deal with the issue of multi-criteria decision-making. Finally, using PyFZN data we also provide a numerical example to demonstrate the usability of the created multicriteria decision-making (MDM) approach. Moreover, a case study also proves its efficacy.

Dinny Indrian, Kurniawan Kurniawan, Sindydevia Rahayu

Laporan WHO menyebutkan 372.441 orang meninggal setiap tahun disebabkan oleh tenggelam. Upaya kuratif untuk mengatasi tenggelam adalah dengan pengunaan pelampung. Korban yang nyaris tenggelam membutuhkan kecepatan penanganan. Oleh karena itu, pengembangan pelampung diarahkan pada peningkatan kecepatan gerak pelampung. Dalam penelitian dilakukan pencarian hubungan antara geometri penampang pelampung dengan kecepatan gerak optimum. Metodologi penyelesaian pada tugas akhir ini adalah studi literatur, identifikasi masalah (perhitungan volume pelampung), rancangan dan parameter desain pelampung, studi sensitivitas pelampung terhadap payload 100 kg, mengecek batas ergonomi, studi dinamika fluida komputasi (CFD) dan mengecek kecepatan alir fluida pada pelampung. Berdasarkan hasil penelitian yang dilakukan, masing – masing bentuk penampang memiliki karakterstik tersendiri. Sehingga beberapa penampang direkomendasikan untuk dikaji lebih lanjut untuk mencapai target dan efektifitas yang diinginkan.

Bingyu Zhang

In this paper, we construct a sequence $(c_k)_{k\in\mathbb{N}}$ of symplectic capacities based on the Chiu-Tamarkin complex $C_{T,\ell}$, a $\mathbb{Z}/\ell$-equivariant invariant coming from the microlocal theory of sheaves. We compute $(c_k)_{k\in\mathbb{N}}$ for convex toric domains, which are the same as the Gutt-Hutchings capacities. Our method also works for the prequantized contact manifold $T^*X\times S^1$. We define a sequence of "contact capacities" $([c]_k)_{k\in\mathbb{N}}$ on the prequantized contact manifold $T^*X\times S^1$, and we compute them for prequantized convex toric domains.

Shunyi Zhang, Brad L. Kinsey

During magnetic pulsed welding (MPW), a wavy interface pattern can be observed. However, this depends on the specific material combination being joined. Some combinations, e.g., steel to aluminum, simply provide undulating waves, while others, e.g., titanium to copper, provide elegant vortices. These physical features can affect the strength of the joint produced, and thus a more comprehensive understanding of the material combination effects during MPW is required. To investigate the interfacial morphology and parent material properties dependency during MPW, tubular Al1100 and various copper alloy joints were fabricated. The influence of two material properties, i.e., yield strength and density, were studied, and the interface morphology features were visually investigated. Results showed that both material properties affected the interface morphology. Explicitly, decreasing yield strength (Cu101 and Cu110) led to a wavy interface, and decreasing density (Cu110 and CP-Ti) resulted in a wave interface with a larger wavelength. Numerical analyses were also conducted in LS-DYNA and validated the interface morphologies observed experimentally. These simulations show that the effect on shear stresses in the material is the cause of the interface morphology variations obtained. The results from this research provide a better fundamental understanding of MPW phenomena with respect to the effect of material properties and thus how to design an effective MPW application.

Jan Kalich, Uwe Füssel

The multi-material design and the adaptability of a modern process chain require joining connections with specifically adjustable mechanical, thermal, chemical, or electrical properties. Previous considerations primarily focused on the mechanical properties. The multitude of possible combinations of requirements, materials, and component- and joining-geometry makes an empirical determination of these joining properties for the clinching process impossible. Based on the established and empirical procedure, there is currently no model that takes into account all questions of joinability—i.e., the materials (suitability for joining), design (security of joining), and production (joining possibility)—that allows a calculation of the properties that can be achieved. It is therefore necessary to describe the physical properties of the joint as a function of the three binding mechanisms—form closure, force closure, and material closure—in relation to the application. This approach illustrates the relationships along the causal chain “joint requirement-binding mechanism-joining parameters” and improves the adaptability of the mechanical joining technology. Geometrical properties of clinch connections of the combination of aluminum and steel are compared in a metallographic cross-section. The mechanical stress state of the rotationally symmetrical clinch points is qualified with a torsion test and by measuring the electrical resistance in the base material, in the clinch joint, and during the production cycle (after clinching, before precipitation hardening and after precipitation hardening).

Suely de Carvalho Roma, André Marques Cavalcanti, Auristela Maria da Silva

A economia da região semiárida do nordeste brasileiro historicamente sempre esteve ligada ao leite bovino. Este estudo tem por objetivo analisar se no modelo de gestão adotada no aglomerado da pequena indústria do leite há processo de inovação. Para atingir esse objetivo, foi realizada uma pesquisa de campo a partir de entrevista estruturada com base nos requisitos do modelo teórico de inovação aberta. Dentre os achados deste estudo, os pesquisados mostram-se limitados e passivos às técnicas que já existem e dominam, como também aos conceitos e ações que viabilizem a adoção de um perfil inovador. Propor um modelo de processo de inovação aberta como fator estratégico de desenvolvimento deste setor é uma possibilidade que está alinhada com a condição das empresas investigadas.

Junaid ur Rehman, Youngmin Jeong, Jeong San Kim et al.

Holevo capacity is the maximum rate at which a quantum channel can reliably transmit classical information without entanglement. However, calculating the Holevo capacity of arbitrary quantum channels is a nontrivial and computationally expensive task since it requires the numerical optimization over all possible input quantum states. In this paper, we consider discrete Weyl channels (DWCs) and exploit their symmetry properties to model DWC as a classical symmetric channel. We characterize lower and upper bounds on the Holevo capacity of DWCs using simple computational formulae. Then, we provide a sufficient and necessary condition where the upper and lower bounds coincide. The framework in this paper enables us to characterize the exact Holevo capacity for most of the known special cases of DWCs.