Search Results (50)

Established hairpin stators for electric traction motors are made up of a large number of so-called hairpins. To produce these stators, the individual hairpins must first be pre-assembled into an auxiliary device in order to achieve the desired winding scheme. The resulting hairpin basket must then be picked up and transported to the lamination stack. Automated solutions for both processes are characterized by a high degree of complexity and low flexibility. Manual assembly, however, is prone to errors. The new approach presented in this paper is therefore based on the collaborative assembly of the hairpins and a flexible hairpin basket gripper. A cobot hands the hairpins in the correct sequence to the operator. The correct positioning of the hairpins in the auxiliary device is ensured by the use of a monitor located under it. The creation of the correct assembly sequence is partly automated by a collision detection program. In addition, a new and flexible hairpin basket gripping concept is presented. Tests show that the cycle times of both new processes are slow due to hardware limitations. This restricts their use to specific applications, such as complex winding patterns or very small quantities. Full article

Background: Primary ciliary dyskinesia (PCD) is a rare genetic disorder characterized by recurrent sinopulmonary infections due to motile cilia defects. The disease is genetically heterogeneous, with abnormalities in structural ciliary proteins. Zinc finger MYND-type containing 10 (ZMYND10) is essential for the assembly of outer dynein arms (ODA), with chaperones like Glucose-regulated protein 78 (GRP78) facilitating protein folding. This study investigates ZMYND10 and Dynein axonemal heavy chain 5 (DNAH5) mutations in individuals with PCD. Methods: Eight individuals aged 14–22 with clinical PCD symptoms and confirmed DNAH5 mutations were included. We analyzed the correlation between DNAH5 abnormalities and preassembly/chaperone proteins using immunofluorescence labeling. Nasal swabs were double-labeled (DNAH5–β-tubulin, β-tubulin–ZMYND10, β-tubulin–GRP78) and examined via fluorescence microscopy. Serum metabolomics and proteomics were also assessed. Results: The corrected total cell fluorescence (CTCF) levels of DNAH5, ZMYND10, and GRP78 were significantly different between PCD individuals and controls. Metabolomic analysis showed reduced valine, leucine, and isoleucine biosynthesis, with increased malate and triacylglycerol biosynthesis, malate-aspartate and glycerol phosphate shuttles, and arginine/proline metabolism, suggesting mitochondrial and ER stress. Conclusions: The altered expression of DNAH5, ZMYND10, and GRP78, along with metabolic shifts, points to a complex link between ciliary dysfunction and cellular stress in PCD. Further studies are needed to clarify the underlying mechanisms. Full article

A study of cryogenic drilling in sandwich composites was carried out. The materials used were carbon-fiber-reinforced polymer sandwich sheets with an inner foamed polyvinyl chloride core, composites with applications including protection structures of polar engineering equipment. The purpose of this study was to determine the feasibility of drilling at low temperatures using this composite by analyzing the thrust forces and the inlet and outlet diameters of the hole due to their influence on hole quality and their importance in a preassembly operation. Experimental tests were performed in laminates with thicknesses of 12 mm and 6 mm, drilling with liquid nitrogen (LN₂) as a refrigerant to reach temperatures below −120 °C under cutting conditions of 2000–6000 rpm for drill bit rotation speeds and 200–600 mm/min for feed rates. Variables such as thrust forces and circularity error were measured, and a design of experiments, analysis of variance, and regression models allowed us to identify the influence of cutting conditions and foam thickness. Optimal cutting conditions were identified and contrasted: 2100–3100 rpm for drill bit rotation speeds and 200–320 mm/min for feed rates. The diameters achieved low deviations, H7 and H8 tolerances for inlet and outlet diameters, respectively, which allows for avoiding additional preassembly operations, which can be important during plate assembly using LN₂ and in maintenance operations. Although good results have been obtained with other materials such as glass-fiber- and carbon-fiber-reinforced polymers, this sandwich material is lighter. Full article

In circular production lines, issues such as positional errors, manufacturing errors at different square groove workstations, and the accumulation of errors during continuous assembly reduce the assembly success rate and limit efficiency. To address these challenges in assembling square groove parts, this study focuses on the jamming and wedging problems encountered during the assembly of square grooves and square parts. It analyzes typical assembly hole searching contact situations and proposes corresponding strategies. Based on the relative geometric relationships between the assembly workpieces, the entire assembly process is divided into three stages: pre-assembly, hole search contact adjustment, and insertion. Due to the complexity of predicting assembly forces and the uncertainty of workstation assembly in circular production lines, this study emphasizes the hole search contact adjustment stage. An innovative vertical hole search strategy is proposed and compared with the Archimedes spiral search method. This strategy models the contact between the end effector and the environment as a mass–damping–spring second-order system, achieving compliant assembly of square holes through admittance control. By analyzing the admittance parameters using control variables, the optimal admittance parameters are determined, and the admittance parameter pattern is applied in the experiments. Experimental results on the square hole assembly platform show that, under the optimal admittance parameters, the vertical hole search strategy significantly reduces search time and improves efficiency. Compared to the traditional Archimedes spiral hole search strategy, the average search adjustment time was increased by 5.8 s, improving efficiency by 46.4%, and the desired assembly outcomes were achieved. Full article

The digitalization of shipbuilding processes has become an important trend in modern naval construction, enabling more efficient design, assembly, and maintenance operations. A key aspect of this digital transformation is traceability, which ensures that every component and step in the shipbuilding process can be accurately tracked and managed. Traceability is critical for quality assurance, safety, and operational efficiency, especially when it comes to identifying and addressing defects that may arise during construction. In this context, defect traceability plays a key role, enabling manufacturers to track the origin, type, and evolution of issues throughout the production process, which are fundamental for maintaining structural integrity and preventing failures. In this paper, we focus on the detection of defects in minor and simple pre-assemblies, which are among the smallest components that form the building blocks of ship assemblies. These components are essential to the larger shipbuilding process, yet their defects can propagate and lead to more significant issues in the overall assembly if left unaddressed. For that reason, we propose an intelligent approach to defect detection in minor and simple pre-assembly pieces by implementing unsupervised learning with convolutional autoencoders (CAEs). Specifically, we evaluate the performance of five different CAEs: BaseLineCAE, InceptionCAE, SkipCAE, ResNetCAE, and MVTecCAE, to detect overshooting defects in these components. Our methodology focuses on automated defect identification, providing a scalable and efficient solution to quality control in the shipbuilding process. Full article

Offshore wind energy has achieved significant reductions in its levelized cost of energy (LCoE) in the past decade, but still needs efficiency improvements. Approximately 18% of the LCoE is related to logistical costs, underscoring the need for optimization in this area. Despite its importance, logistical decisions during offshore wind farm installations remain underexplored in the literature. This article aims to identify and structure the relationships of logistic decisions to optimize total installation costs. A conceptual framework is proposed, detailing logistical decisions and their influencing factors. The results are based on a literature review and survey research for validation with specialists in logistics and offshore wind farms. The findings include the key decisions: port installation selection; vessel fleet selection; installation strategy selection; turbine pre-assembly method selection; aggregate planning approach; installation schedule coverage; storage strategy of components; and the degree of sharing information. The framework reveals the importance of coordinating the value chain in the installation process, mainly due to the influence of weather factors; the logistic decisions, when considered in a systemic view, can contribute to a global efficiency gain in the installation process. Full article

Background/Objectives: Transgene applications, ranging from gene therapy to the development of stable cell lines and organisms, rely on maintaining the expression of transgenes. To date, the use of plasmid-based transgenes has been limited by the loss of their expression shortly after their delivery into the target cells. The short-lived expression of plasmid-based transgenes has been largely attributed to host-cell-mediated degradation and/or silencing of transgenes. The development of chromatin-based strategies for gene delivery has the potential to facilitate defining the requirements for establishing epigenetic states and to enhance transgene expression for numerous applications. Methods: To assess the impact of “priming” plasmid-based transgenes to adopt accessible chromatin states to promote gene expression, nucleosome positioning elements were introduced at promoters of transgenes, and vectors were pre-assembled into nucleosomes containing unmodified histones or mutants mimicking constitutively acetylated states at residues 9 and 14 of histone H3 or residue 16 of histone H4 prior to their introduction into cells, then the transgene expression was monitored over time. Results: DNA sequences capable of positioning nucleosomes could positively impact the expression of adjacent transgenes in a distance-dependent manner in the absence of their pre-assembly into chromatin. Intriguingly, the pre-assembly of plasmids into chromatin facilitated the prolonged expression of transgenes relative to plasmids that were not pre-packaged into chromatin. Interactions between pre-assembled chromatin states and nucleosome positioning-derived effects on expression were also assessed and, generally, nucleosome positioning played the predominant role in influencing gene expression relative to priming with hyperacetylated chromatin states. Conclusions: Strategies incorporating nucleosome positioning elements and the pre-assembly of plasmids into chromatin prior to nuclear delivery can modulate the expression of plasmid-based transgenes. Full article

Promyelocytic leukemia (PML) nuclear bodies (PML-NBs) are core–shell-type membrane-less organelles typically found in the nucleus of mammalian somatic cells but are absent in mouse oocytes. Here, we deliberately induced the assembly of PML-NBs by injecting mRNA encoding human PML protein (hPML VI -sfGFP) into oocytes and investigated their impact on fertilization in which oocyte/embryos undergo multiple types of stresses. Following nuclear membrane breakdown, preassembled hPML VI -sfGFP mRNA-derived PML-NBs (hmdPML-NBs) persisted in the cytoplasm of oocytes, forming less-soluble debris, particularly under stress. Parthenogenetic embryos that successfully formed pronuclei were capable of removing preassembled hmdPML-NBs from the cytoplasm while forming new hmdPML-NBs in the pronucleus. These observations highlight the beneficial aspect of the PML-NB-free nucleoplasmic environment and suggest that the ability to eliminate unnecessary materials in the cytoplasm of metaphase oocytes serves as a potential indicator of the oocyte quality. Full article

The global push for sustainable energy has heightened the demand for green hydrogen, which is crucial for decarbonizing heavy industry. However, current electrolysis plant capacities are insufficient. This research addresses the challenge through optimizing large-scale electrolysis construction via standardization, modularization, process optimization, and automation. This paper introduces H₂Giga, a project for mass-producing electrolyzers, and HyPLANT100, investigating large-scale electrolysis plant structure and construction processes. Modularizing electrolyzers enhances production efficiency and scalability. The integration of AutomationML facilitates seamless information exchange. A digital twin concept enables simulations, optimizations, and error identification before assembly. While construction site automation provides advantages, tasks like connection technologies and handling cables, tubes, and hoses require pre-assembly. This study identifies key tasks suitable for automation and estimating required components. The Enapter Multicore electrolyzer serves as a case study, showcasing robotic technology for tube fittings. In conclusion, this research underscores the significance of standardization, modularization, and automation in boosting the electrolysis production capacity for green hydrogen, contributing to ongoing efforts in decarbonizing the industrial sector and advancing the global energy transition. Full article

This paper presents a novel approach to developing fully automated intelligent control systems for use within production-based organizations, with a specific focus on advancing research into intelligent production systems. This analysis underscores a prevailing deficiency in control operations preceding assembly, where single-purpose control machines are commonly utilized, thus presenting inherent limitations. Conversely, while accurate multipurpose measurement centers exist, they often fail to deliver comprehensive quality control for manufactured parts due to cost and time constraints associated with the measuring process. The primary aim in this study was to develop an intelligent modular control system capable of overseeing the production of diverse components effectively. The modular intelligent control system is designed to meticulously monitor the quality of each module during the pre-assembly phase. By integrating sophisticated sensors, diagnostic tools, and intelligent control mechanisms, this system ensures precise control over module production processes. It facilitates the monitoring of multiple parameters and critical quality features, while integrated sensors and diagnostic methods promptly identify discrepancies and inaccuracies, enabling the swift diagnosis of issues within specific modules. The system’s intelligent control algorithms optimize production processes and ensure synchronization among individual modules, thereby ensuring consistent quality and performance. Notably, the implementation of this solution reduces inspection time by an average of 40 to 60% compared to manual inspection methods. Moreover, the system enables the comprehensive archiving of measurement data, eliminating the substantial error rates introduced by human involvement in the inspection process. Furthermore, the system enhances overall project efficiency, predictability, and safety, while allowing for rapid adjustments in order to meet standards and requirements. This innovative approach represents a significant advancement in intelligent control systems for use in production organizations, offering substantial benefits in terms of efficiency, accuracy, and adaptability. Full article

(1) Background: Demographic changes over the past decade have had a significant impact on pelvic ring fractures. They have increased dramatically in the orthogeriatric population. Surgeons are faced with implant fixation issues in the treatment of these fragility fractures. This study compares two innovative implants for stabilizing the iliosacral joint in a biomechanical setting. (2) Methods: An iliosacral screw with a preassembled plate allowing the placement of an additional short, angular stable screw in the ilium and a triangular fixation system consisting of a fenestrated ilium screw and an iliosacral screw quasi-statically inserted through the “fenestra” were instrumented in osteoporotic artificial bone models with a simulated Denis zone 1 fracture. Biomechanical testing was performed on a servo-hydraulic testing machine using increasing, synchronous axial and torsional sinusoidal cyclic loading to failure. (3) Results: The SI-Plate and TriFix showed comparable stiffness values. The values for fracture gap angle and screw tip cutout were significantly lower for the TriFix compared to the SI-Plate. In addition, the number of cycles to failure was significantly higher for the TriFix. (4) Conclusions: Implant anchorage and primary stability can be improved in iliosacral instability using the triangular stabilization system. Full article

In this study, 220 AA7075-T6 B-pillars were fabricated using a thoroughly instrumented hot-stamping press under varied conditions. Feature engineering work identified nineteen attributes of the hot-stamping process as impacting four characteristics of the obtained B-pillars: electrical conductivity (%IACS), mechanical strength, distortion, and the presence of visible defects. Pearson correlation suggests an important correlation between the heating phase and the mechanical strength, as well as the %IACS values. As for distortion, the influence of the stamping phase is more obvious. Finally, no correlation was obtained between the hot stamping attributes and the presence of visible cracks. This is mainly due to the pre-assembly phase, i.e., Friction Stir Welding, which will be considered in future works. Full article

Guanine crystals with unique optical properties in organisms have been extensively studied and the biomineralization principles of guanine are being established. This review summarizes the fundamental physicochemical properties (solubility, tautomers, bands, and refractivity), polymorphs, morphology of biological and synthetic forms, and the reported biomineralization principles of guanine (selective recrystallization of amorphous precursor, preassembled scaffolds, additives, twinning, hypoxanthine doping, fluorescence, and assembly). The biomineralization principles of guanine will be helpful for the synthesis of guanine crystals with excellent properties and the design of functional organic materials for drugs, dyes, organic semiconductors, etc. Full article

Infection with cytomegalovirus (CMV) is highly prevalent in the general population and largely controlled by CD8^pos T cells. Intriguingly, anti-CMV T cells accumulate over time to extraordinarily high numbers, are frequently present as tumor-resident ‘bystander’ T cells, and remain functional in cancer patients. Consequently, various strategies for redirecting anti-CMV CD8^pos T cells to eliminate cancer cells are currently being developed. Here, we provide an overview of these strategies including immunogenic CMV peptide-loading onto endogenous HLA complexes on cancer cells and the use of tumor-directed fusion proteins containing a preassembled CMV peptide/HLA-I complex. Additionally, we discuss conveying the advantageous characteristics of anti-CMV T cells in adoptive cell therapy. Utilization of anti-CMV CD8^pos T cells to generate CAR T cells promotes their in vivo persistence and expansion due to appropriate co-stimulation through the endogenous (CMV-)TCR signaling complex. Designing TCR-engineered T cells is more challenging, as the artificial and endogenous TCR compete for expression. Moreover, the use of expanded/reactivated anti-CMV T cells to target CMV peptide-expressing glioblastomas is discussed. This review highlights the most important findings and compares the benefits, disadvantages, and challenges of each strategy. Finally, we discuss how anti-CMV T cell therapies can be further improved to enhance treatment efficacy. Full article

This paper presents the performance of a new, floating, mono-hull wind turbine installation vessel (Nordic Wind) in the installation process. The vessel can transport pre-assembled wind turbines from the marshalling port to the offshore installation site. Each assembled turbine will be positioned over the pre-installed floating spar structure. The primary difficulty lies in examining the multibody system’s reactions when subjected to combined wind, current, and wave forces. Time-domain simulations are utilized to model the interconnected system, incorporating mechanical coupling between components, the mooring system for the spar, and the installation vessel. The primary objective is to focus on the monitoring and connection stages preceding the mating operations between the turbine and the floating spar. Additionally, it involves examining the impacts of wind, current, and wave conditions on the motion responses of the installation vessel and the spar, as well as the relative motions at the mating point, gripper forces, and mooring forces. The simulations show that the resulting gripper forces are reasonable to compensate. The relative motion at the mating point is not significantly affected by the orientations of the turbine blades, but it is influenced by the prevailing wave conditions. In addition, vessel heading optimization can minimize the relative motions at the mating point and gripper forces. Given the examined environmental conditions, the presented installation concept exhibits a commendable performance. Full article