Search Results (9)

To enhance the mechanical characteristics and corrosion resistance of bridge steel, three distinct groups of test steels with varying Ce contents were formulated. The objective was to investigate the influence of rare earth Ce on the microstructure, impact performance, and corrosion resistance of bridge steel. The addition of rare earth elements improves both the impact performance and the corrosion resistance of bridge steels. The present research systematically examines the impact of cerium (Ce) incorporation on the structural and impact performance of bridge construction steels, with particular emphasis on elucidating the fundamental mechanisms governing these modifications. This investigation establishes a comprehensive theoretical framework that facilitates the advancement of next-generation rare earth-enhanced high-performance steel alloys specifically designed for bridge engineering applications. The investigation reveals that rare-earth elements exert a significant influence on microstructural refinement, leading to the diminution of grain size. Additionally, these elements catalyze the modification of inclusion morphology in the test steel, transitioning from an irregular form to a spherical one, with a concomitant decrease in inclusion size. The tested steel with a rare earth mass fraction of 0.0025 wt.% has the best impact performance and the lowest corrosion rate. The impact performance improved by 7.37% compared with the experimental steel without the addition of rare earth elements. The incorporation of rare earth elements has been observed to promote the accumulation of Cu in the rust layer, which contributes to the improved stability of the layer. Concurrently, it has been noted that, for equivalent periods of corrosion exposure, there is a positive correlation between the arc radius of bulk resistance and the incremental levels of rare earth Ce. Full article

Ce-based catalysts have been widely used in the removal of nitrogen oxides from industrial flue gas because of their good catalytic performance and environmental friendliness. However, the mechanism of alkali metal poisoning in Ce-based catalysts remains to be further studied. This work involves the preparation of the K/Na-poisoned CeWTi catalyst via the impregnation method for assessing its performance in NO removal. Experiments show that both K and Na exhibit detrimental effects on the CeWTi catalyst, and the loading of alkali metal reduces the specific surface area and pore volume of the catalyst. Furthermore, the presence of alkaline metals results in a notable decline in the CeWTi acid concentration, particularly in Lewis acid sites. Concurrently, the levels of Ce³⁺, oxygen vacancies, and reducing agents on the catalyst surface decrease, leading to diminished reduction capability and eventual catalyst deactivation. The application of a BP neural network for catalyst activity prediction yielded an average relative error of approximately 0.73%, indicating enhanced accuracy in prediction outcomes. This work explored the cause of alkali metal poisoning of the CeWTi catalyst and provided an effective prediction method for the lifetime of CeWTi catalyst, which provided theoretical guidance for the engineering application of Ce-based catalysts. Full article

Market trends in the space sector suggest a notable increase in satellite operations and market value for the coming decade. In parallel, there has been a shift in the industrial and academic sectors from traditional Document-Based System Engineering to Model-based systems engineering (MBSE) combined with Concurrent engineering (CE) practices. Due to growing demands, the drivers behind this change have been the need for quicker and more cost-effective design processes. A key challenge in this transition remains to determine how to effectively formalize and exchange data during all design stages and across all discipline-specific tools; as representing systems through models can be a complex endeavor. For instance, during the Preliminary design (PD) phase, the integration of system models with external mathematical models for simulations, analyses, and system budgeting is crucial. The introduction of CubeSats and their standard has partly addressed the question of standardization and has aided in reducing overall development time and costs in the space sector. Nevertheless, questions about how to successfully exchange data endure. This paper focuses on formalizing a CubeSat model for use across various stages of the PD phase. The entire process is conducted with the exclusive use of open-source tools, to facilitate the transparency of data integration across the PD phases, and the overall life cycle of a CubeSat. The paper has two primary outcomes: (i) developing a generic CubeSat model using Systems modeling language (SysML) that includes data storage and visualization through the application of Unified modeling language (UML) stereotypes, streamlining in parallel information exchange for integration with various simulation and analysis tools; (ii) creating an end-to-end use case scenario within the Nanostar software suite (NSS), an open-source framework designed to streamline data exchange across different software during CE sessions. A case study from a theoretical academic space mission concept is presented as the illustration of how to utilize the proposed formalization, and it serves as well as a preliminary validation of the proposed formalization. The proposed formalization positions the CubeSat SysML model as the central data source throughout the design process. It also supports automated trade-off analyses by combining the benefits of SysML with effective data instantiating across all PD study phases. Full article

Furniture production is a specific industrial sector with a high human labor demand, a wide range of materials processed, and short production runs caused by high customization of end products. The difficulty of measuring the aesthetic requirements of customers is also specific to furniture. This review of academic papers identifies and explains effective quality management strategies in furniture production. The reviewed literature highlights a range of quality management methodologies, including concurrent engineering (CE), total quality management (TQM), lean manufacturing, lean six sigma, and kaizen. These strategies encompass a variety of pro-quality tools, such as 5S, statistical process control (SPC), quality function deployment (QFD), and failure mode and effects analysis (FMEA). The strengths of these quality management strategies lie in their ability to enhance efficiency, reduce waste, increase product diversity, and improve product quality. However, the weaknesses concern implementation challenges and the need for culture change within organizations. Successful quality management in furniture production requires tailoring strategies to the specific context of the furniture production industry. Additionally, the importance of sustainability in the furniture industry is emphasized, which entails incorporating circular economy principles and resource-efficient practices. The most important finding from the literature analysis is that early detection and correction of poor quality yields the most beneficial outcomes for the manufacturer. Therefore, it is essential to strengthen the rigor of quality testing and analysis during the early stages of product development. Consequently, a deep understanding of consumer perspectives on required furniture quality is crucial. The review identified two research gaps: (1) the impact of unnecessary product over-quality on the efficiency of furniture production and (2) the influence of replacing CAD drawings with a model-based definition (MBD) format on quality management in furniture production. Full article

The increasing release of engineered nanoparticles (NPs) into aquatic ecosystems makes it crucial to understand the interactions of NPs with aquatic organisms, such as algae. In this study, the association of CeO₂ NPs with unicellular algae (Raphidocelis subcapitata) and changes to the cellular elemental profile were investigated using three exposure concentrations (1, 50, and 1000 µg CeO₂/L) at two different algal growth conditions—exponential and inhibited growth (1% glutaraldehyde). After a 24 h-exposure, algal suspensions were settled by gravity and CeO₂-NP/algae association was analyzed by single-cell inductively coupled plasma quadrupole mass spectrometry (sc-ICP-QMS) and ICP time-of-flight MS (sc-ICP-TOFMS). Concurrent detection of the cellular fingerprint with cerium indicated NP association with algae (adsorption/uptake) and changes in the cellular elemental profiles. Less than 5% of cells were associated with NPs when exposed to 1 µg/L. For 50 µg/L exposures in growing and inhibited cell treatments, 4% and 16% of cells were associated with CeO₂ NPs, respectively. ICP-TOFMS analysis made it possible to exclude cellular exudates associated with CeO₂ NPs due to the cellular fingerprint. Growing and inhibited cells had different elemental profile changes following exposure to CeO₂ NPs—e.g., growing cells had higher Mg and lower P contents independent of CeO₂ concentration compared to inhibited cells. Full article

In this decade, all researchers and industry players compete to develop sustainable product design by exploring natural fibre composites in product design development. One of the essential methodologies in creating composite products is concurrent engineering (CE). Industrial design and production engineering should be involved in the development of ballistic helmets. This publication aims to provide a quick overview of the evolution of natural fibre composite ballistic helmet designs. This manuscript is still in its early stages, but it already includes a summary of the progress of ballistic helmet design from 1915 to the present. Renewable materials, such as natural fibre, should be highlighted as an alternative to synthetic composites in developing a sustainable ballistic helmet design. Furthermore, launching the design development process for a ballistic helmet demands a CE strategy that includes multi-disciplinary knowledge. Computational modelling aids in the development of ballistic helmet designs, reducing the time and cost of manufacturing ballistic helmets. The ergonomic component of ballistic helmet design is also crucial, as is the thermal comfort factor, which can be handled using natural fibre composites with thermal solid insulating characteristics. The development of natural fibre composite ballistic helmets can be used as a consideration in the future as a revolution to create a sustainable design. Finally, this review can be used as a guide for industrial designers. In conclusion, this review might be utilized as a reference for industrial designers due to a shortage of studies, especially in producing product-related natural fibre. Full article

Concurrent engineering (CE) aims to provide a collaborative environment in which all involved parties work simultaneously to optimize resources. However, some aspects can make it hard to implement in organizations. This study presents the development of a CE model and its implementation in a Mexican textile maquiladora. The information about the process was obtained using administrative and quality tools (brainstorming, Pareto and Ishikawa charts, flowcharts, spreadsheets). A CE model based on the management of new products was designed, in consideration of the enterprise culture. The workgroup evaluated the proposed model in two projects to verify the functionality. The time for the development and approval of prototypes was reduced from three months to one. Now the process has a robust design, having identified design problems, potential operator errors, and bottlenecks. Losses from raw material replacements and reworks decreased by 39.4%, and there was an additional cost saving of 22.86%. CE implementation is not easy; the firsts steps are to change the organizational culture and the training of employees to work collaboratively. Full article

Due to the highly competitive commercial environment in the market in Yemen at present, the construction industry in Yemen, like other industries, is under pressure to reduce product development time and overall project costs, improve product quality, and satisfy customers. To keep pace with the competitive environment of the market in Yemen, most enterprises tend to adopt the best and new technologies, new management concepts and philosophies such as Total Quality Management (TQM) and concurrent engineering (CE) to achieve improvements in the process of product development. In this paper, the problem of fragmentation brought by the serial engineering in construction in Yemen is discussed firstly. Then, the integration process and CE adoption by the construction industry in Yemen are explained for enabling construction agencies in Yemen to improve the development process of their projects and to solve the current fragmentation problems such as the lack of communication, adversarial culture and the lack of customer focus, which allows the construction process to improve and become more effective and efficient. Full article

A common barrier to achieving design intent is the absence of comprehensive information about operational performance during design development. This results in uninformed decision-making which impacts on actual building performance, in particular Whole Life Costs (WLC). It is proposed that Building Information Modelling (BIM) has the potential to facilitate a more comprehensive and accurate design approach from the initial stages if the model can utilize reliable and robust cost and performance data from buildings in use. This paper describes the initial findings of a research project that has investigated the integration of WLC estimation into BIM processes. The study focusses specifically on the rapidly emerging Private Rental Sector (PRS) as the build-to-rent market has repeatable tasks and similar workflow patterns, roles and responsibilities, but impacts of WLC can significantly influence the business model. The study adopted a mixed method approach for the development and validation of a structured standardized process for timely WLC estimation through BIM. The research identified a number of barriers. These included varying definitions of WLC calculation methodologies; the availability and standards of data sources, in particular, the misalignment of coding systems for identification and classification of components at various levels of development, proprietary ownership of data, lack of knowledge and skills in team members to produce and/or utilize data sources, and limitations of software. However, the research proposes that these may be addressed by a reverse-engineered systematic process that uses the Integrated DEFinition (IDEF) 3 structured diagramming modelling technique that can be incorporated into a software model and has developed a model for a systematic approach for BIM-enabled WLC assessment based on CE principles which would include access to live data streams from completed buildings. The paper describes this model development which has the potential to enhance BIM lifecycle management through an augmented decision-making approach that is integral to the natural design development process. Full article