Electromagnetic braking (EMBr) technology, as one of the most effective technologies in the continuous casting process, provides an effective tool for improving the internal and external defects of steel products. Specifically, the EMBr technology takes the benefit of the generation of Lorentz force to decrease flow instability, mold powder entrapment, and surface defects, if applied properly. For this purpose, to gain a clear understanding of the effect of EMBr technology on the continuous casting process, a commonly used EMBr technology, namely ruler EMBr technology, is applied in the current work to investigate the dynamic behaviors of molten steel flow and steel−slag interface fluctuation inside a slab mold. Furthermore, to obtain a desirable braking effect of the ruler EMBr technology, operational parameters including the magnetic flux density, submerged entry nozzle (SEN) depth, and magnetic pole location are numerically investigated. The results demonstrate that the braking effe... [more]

The delays and disruptions during the pandemic have awakened interest in the sustainability and resilience of production systems to emergencies. In that context, the deployment of smart technologies has emerged as an almost mandatory development orientation to ensure the stability of manufacturing. The core value of smart technologies is to reduce the dependence on human labor in production systems. Thereby, the negative impacts caused by emergency situations are mitigated. However, the implementation of smart technologies in a specific production system that already exists requires a high degree of suitability. Motivated by this fact, this study proposes an integrated spherical fuzzy bounded rationality decision-making approach, which is composite of the spherical fuzzy decision-making trial and evaluation laboratory (SF DEMATEL) and the spherical fuzzy regret theory-based combined compromise solution (R-SF CoCoSo) method. The proposed approach reflects both the ambiguities and psycho... [more]

The development of active packaging for food storage containers is possible through impregnation of natural extracts by supercritical CO2-assisted impregnation processes. The challenge of scCO2-impregnation of natural extracts is to control the total loading and to ensure that the composition of the loaded extract may preserve the properties of the crude extract. This study aimed at investigating the scCO2-impregnation of clove extract (CE) in polycarbonate (PC) to develop antibacterial packaging. A design of experiments was applied to evaluate the influences of temperature (35−60 °C) and pressure (10−30 MPa) on the clove loading (CL%) and on the composition of the loaded extract. The CL% ranged from 6.8 to 18.5%, and the highest CL% was reached at 60 °C and 10 MPa. The composition of the impregnated extract was dependent on the impregnation conditions, and it differed from the crude extract, being richer in eugenol (81.31−86.28% compared to 70.06 in the crude extract). Differential sc... [more]

This article discusses the flow of a non-Newtonian Carreau nanoliquid across a stretching radiative nonlinear sheet that is exposed to a variable heat flux. Analysis is done with changing thermal conductivity since it affects how heat and mass transfer occur. Nanoparticles are modelled using the Brownian motion and the thermophoresis phenomenon. The introduction of a similar solution to our challenge, as obtained by our paper, received significant attention. To create a dimensionless system, the governing partial differential equations are subjected to the mathematical model’s convenient similarity transformations after it has been developed. The numerical solution of the coupled highly nonlinear ordinary differential equations characterizing velocity, temperature and nanoparticles concentration is shown using an effective shooting approach. Additionally, all factors affecting the situation that could increase the effectiveness of cooling operations will be looked into. Results for vel... [more]

Modern manufacturing operations always aim toward sustainable production through sustainable operations. Lean Six Sigma manufacturing is one of the leading models to increase operational efficiency and productivity and reduce product manufacturing costs. The lean Six Sigma problem-solving methodology DMAIC has been one of the several techniques organizations use to improve their productivity and the quality of their product and services. This paper aims to apply Lean Six Sigma and DMAIC to enhance production capacity and reduce per-unit cost. Furthermore, this research work has been carried out to analyze the impact of stakeholders on Lean Six Sigma projects. The research follows the DMAIC methodology to investigate and analyze the root cause of the problems and give possible solutions for eliminating or reducing the issues. Particularly, fishbone and 5-Whys techniques were used to determine whether the two key processes, AC Outdoor unit testing with the help of reusable power cords an... [more]

Industry 5.0 presents itself as a strategy that puts the human factor at the centre of production, where the well-being of the worker is prioritized, as well as more sustainable and resilient production systems. For human centricity, it is necessary to empower human beings and, respectively, industrial operators, to improve their individual skills and competences in collaboration or cooperation with digital technologies. This research’s main purpose and distinguishing point are to determine whether Industry 5.0 is truly human-oriented and how human centricity can be created with Industry 5.0 technologies. For that, this systematic literature review article analyses and clarifies the concepts and ideologies of Industry 5.0 and its respective technologies (Artificial Intelligence, Robotics, Human-robot collaboration, Digitalization), as well as the strategies of human centricity, with the aim of achieving sustainable and resilient systems, especially for the worker.

In this study, the comprehensive properties of a P22 high-temperature steam pipeline with moderate spheroidization were evaluated after more than 11,700 h of operation through a series of physico-chemical properties testing, especially for a creep test. The remaining life of the P22 high-temperature steam pipeline was analyzed and predicted by the θ parameter method, to guide the normal operation of the P22 high-temperature steam pipeline.

This study proposes a task-offloading and resource allocation strategy in multidomain cooperation (TARMC) for the industrial Internet of Things (IIoT) to resolve the problem of the non-uniform distribution of task computation among various cluster domain networks in the IIoT and the solidification of traditional industrial wireless network architecture, which produces low efficiency of static resource allocation and high delay in closed-loop data processing. Based on the closed-loop process of task interaction of intelligent terminals in wireless networks, the proposed strategy constructs a network model of multidomain collaborative task-offloading and resource allocation in IIoT for flexible and dynamic resource allocation among intelligent terminals, edge servers, and cluster networks. Considering the partial offloading mechanism, various tasks were segmented into multiple subtasks marked at bit-level per demand, which enabled local and edge servers to process all subtasks in paralle... [more]

Vietnam’s textile and garment enterprises make an important contribution to the country with the second largest export turnover. The existence and development of textile and garment enterprises have a significant influence on the socioeconomic development of Vietnam. Currently, Vietnam’s textile and garment industry is facing difficulties caused by the COVID-19 pandemic, along with competition from foreign direct investment (FDI) enterprises. Therefore, it is imperative for managers to assess competitiveness by measuring their past and current performance indicators. This study assesses the performance of Vietnam’s 10 textile and garment enterprises from 2017 to 2020 by combining the DEA−Malmquist productivity index (MPI) and epsilon-based measure (EBM) model. The proposed model considered three inputs (total assets, cost of goods sold, and liabilities) and two outputs (total revenue and gross profit). In addition to showing the best-performing companies from certain aspects during the... [more]

In this paper, a small centrifugal pump experiment was conducted under conditions of power frequency startup and frequency conversion startup respectively. The evolutionary trends for hydraulic performance parameters with time were obtained, and the transient properties of the two starting modes were revealed with the help of three dimensionless coefficients. This study revealed the similarities and differences between the two starting modes. In both starting modes, the increase of the valve opening caused a time lag for the flow to reach a steady state. Compared with the power frequency startup mode, the frequency conversion startup mode had weaker shaft power shocks and was safer in practice. The dimensionless flow curves maintained a good evolutionary agreement with the corresponding flow curves. The dimensionless shaft power was extremely high at the beginning of startup and then decreased to a stable value.

This study investigated the feasibility of applying an anaerobic step-feeding strategy to enhance the performance of granular sequencing batch reactors (GSBRs) in terms of operational stability of the cultivated mature granules and nutrient removal efficiencies. Two identical 5 L reactors were operated with a total cycle time of 8 h. GSBRs were operated with high-strength synthetic wastewater (COD = 1250 ± 43, ammonium (NH4-N) = 115.2 ± 4.6, and orthophosphate (PO4-P) = 17.02 ± 0.9 mg/L) for 360 days through three stages: (1) Cultivation, 125 days (>2.1 mm); (2) Maturation, 175 days (>3 mm); (3) alternate feed loading strategy for R2 only for 60 days (anaerobic step-feeding). The granulation process, the physical properties of the granules, the nutrients, and the substrate removal performance were recorded during the entire operational period. For the cultivation and maturation stages, both reactors followed the fast single feeding mode followed by anaerobic mixing, and the results ind... [more]

In this paper, performance analysis over two years’ operation of an industrial anaerobic digestion (AD) plant of a separately collected organic fraction of municipal solid waste is presented. The continuous plug-flow AD plant is still regularly operating and it has been fully operational since September 2018. Since then, it has been supplied with 40,000 t/y of pretreated separately collected organic fraction of municipal solid waste from municipalities of the Calabria region in Southern Italy. The AD process is carried out in a mesophilic regime at 40 ± 0.5 °C, using a constant hydraulic retention time (HRT) of 22 days and a substrate with average total solids and average total volatile solids of 30.0% and 22.2%, respectively. In the last two years, the plant produced an average of 191 m3 and 860 m3 of biogas per tonne (t) of organic input material and of total volatile solids, respectively, with an average methane specific production of 508 m3/t (total volatile solids). The average CH... [more]

This research seeks the opportunity to further reduce the minimum GHG emissions achieved by individu-ally operating energy systems in the civic, industrial, and transportation sectors through their integration. Each entity – buildings or industrial plants, is equipped with a set of combined cooling, heating, and pow-er (CCHP) system. At the same time, there is heat and electricity transfer among entities. The integration intends to solve the mismatch between the energy demand and energy provided by the CCHP system, which further increases the operation of the CCHP system and reduces GHG emissions of the entire sys-tem. This research introduces an optimization approach for identifying the optimal design and operation of the integrated system, which provides the maximum GHG emission reduction benefits (represented as GHG emissions reduction percentage (GHGD%)). Compared to existing studies on the integrated system, this research (1) differentiates the temperature of industrial heating de... [more]

Identification of ongoing processes in solid oxide fuel cells (SOFC) enables both optimizing the operating environment and prolonging the lifetime of SOFC. The Levenberg−Marquardt algorithm (LMA) is commonly used in the characterization of unknown electrochemical processes within SOFC by extracting equivalent electrical circuit (EEC) parameter values from electrochemical impedance spectroscopy (EIS) data. LMA is an iteration optimization algorithm regularly applied to solve complex nonlinear least square (CNLS) problems. The LMA convergence can be boosted by the application of an ordinary limit strategy, which avoids the occurrence of off-limit values during the fit. However, to additionally improve LMA descent properties and to discard the problem of a poor initial parameters choice, it is necessary to modify the ordinary limit strategy. In this work, we designed a new automatic update (i.e., adaptive) limit strategy whose purpose is to reduce the impact of a poor initial parameter ch... [more]

The submission includes SimaPro project for LCA of SOFCs with 10-year replacement plan, a text file explaining how to run the SimaPro file, and SOFC inventory tables provided in an Excel file.

In this paper, producing constant power load of 550 MW from systems of Solid Oxide Fuel Cells (SOFCs) operating in varying power output mode was investigated. This is useful because previous research has shown that individual cells can have significant lifetime extensions when operated according to certain dynamic trajectories in which power production decreases over time. In this study, we determined that a constant net power output of a system comprised of many individual SOFC modules can be achieved by scheduling the installation and operation of each SOFC module in a particular manner. All the modules were operated under the optimal operating conditions obtained in our previous optimization study where power output of each module declined over time. The dynamic degradation of SOFCs was taken into ac-count by using a detailed mathematical model of long-term performance degradation as a function of operating conditions. The result is a system in which every 5 days, one new SOFC modul... [more]

Inter-plant hydrogen integration can reduce the consumption of hydrogen utility in petrochemical parks. However, the fluctuation of operating conditions will lead to complex multi-period problems of hydrogen network integration. This work develops a simultaneous optimization approach to solving multi-period optimization problems for the inter-plant hydrogen network. To do this, we consider the inter-plant hydrogen integration and the fluctuation of operating conditions in each plant at the same time, and aim to minimize the total annualized cost of the entire hydrogen system of all plants involved. An industrial case study of a three-plant hydrogen network with seven subperiods was adopted to verify the effectiveness of the proposed method. Results show that the optimal structure and the corresponding scheduling scheme can be obtained when the lowest cost of the system is targeted. Compared with the stepwise methods, the proposed approach features taking the characteristics of all subp... [more]

One popular method for optimizing systems, referred to as ANN-PSO, uses an artificial neural network (ANN) to approximate the system and an optimization method like particle swarm optimization (PSO) to select inputs. However, with reinforcement learning developments, it is important to compare ANN-PSO to newer algorithms, like Proximal Policy Optimization (PPO). To investigate ANN-PSO’s and PPO’s performance and applicability, we compare their methodologies, apply them on steady-state economic optimization of a chemical process, and compare their results to a conventional first principles modeling with nonlinear programming (FP-NLP). Our results show that ANN-PSO and PPO achieve profits nearly as high as FP-NLP, but PPO achieves slightly higher profits compared to ANN-PSO. We also find PPO has the fastest computational times, 10 and 10,000 times faster than FP-NLP and ANN-PSO, respectively. However, PPO requires more training data than ANN-PSO to converge to an optimal policy. This cas... [more]

The dynamic optimization of promising forced periodic processes has always been limited by time-consuming and expensive numerical calculations. The Nonlinear Frequency Response (NFR) method removes these limitations by providing excellent estimates of any process performance criteria of interest. Recently, the NFR method evolved to the computer-aided NFR method (cNFR) through a user-friendly software application for the automatic derivation of the functions necessary to estimate process improvement. By combining the cNFR method with standard multi-objective optimization (MOO) techniques, we developed a unique cNFR−MOO methodology for the optimization of periodic operations in the frequency domain. Since the objective functions are defined with entirely algebraic expressions, the dynamic optimization of forced periodic operations is extraordinarily fast. All optimization parameters, i.e., the steady-state point and the forcing parameters (frequency, amplitudes, and phase difference), ar... [more]

Lyophilization stabilizes formulated biologics for storage, transport and application to patients. In process design and operation it is the link between downstream processing and with final formulation to fill and finish. Recent activities in Quality by Design (QbD) have resulted in approaches by regulatory authorities and the need to include Process Analytical Technology (PAT) tools. An approach is outlined to validate a predictive physical-chemical (rigorous) lyophilization process model to act quantitatively as a digital twin in order to allow accelerated process design by modeling and to further-on develop autonomous process optimization and control towards real time release testing. Antibody manufacturing is chosen as a typical example for actual biologics needs. Literature is reviewed and the presented procedure is exemplified to quantitatively and consistently validate the physical-chemical process model with aid of an experimental statistical DOE (design of experiments) in pil... [more]

The startup period, one of several transient operations in a centrifugal pump, takes note of some problems with these devices. Sometimes a transient high pressure and high flow rate over a very short period of time are required at the startup process. The pump’s dynamic response is delayed because of the rotational inertia of the pump and motor. Our research focuses on how to get a large flow in a short time when the pump cannot meet the requirements alone without a large power driver. To achieve a strong response in the startup process, a ball valve is installed downstream of the pump. The pump’s transient behavior during such transient operations is important and requires investigation. In this study, the external transient hydrodynamic performance and the internal flow of the pump during the transient startup period are studied by experiments and simulations. In order to find an appropriate matching method, different experiments were designed. The content and results of this paper a... [more]

The energy cost of producing steel in an electric arc furnace (EAF) has a sizable influence on the prices of natural gas and electricity. Therefore, it is important to use these energies efficiently via a tailored oxy-fuel combustion burner and oxygen lance. In this study, an important modification of the side-wall injector system in the EAF at Hyundai Steel Incheon works was implemented to reduce electrical energy consumption and improve productivity. A protruding water-cooled copper jacket, including a newly designed burner, was developed to reduce the distance between the jet nozzle and the molten steel. In addition, the jet angles for the burner and lance were separately set for each scrap melting and refining mode. The modifications led to a reduction in electrical energy consumption of 5 kWh/t and an increase in productivity of approximately 3.1 t/h. Consequently, total energy cost savings of 0.3 USD/t and a corresponding annual cost savings of approximately 224,000 USD/year were... [more]

Temporal variations in CO2 stream composition and mass flow rates may occur in a CO2 transport network, as well as further downstream when CO2 streams of different compositions and temporally variable mass flow rates are fed in. To assess the potential impacts of such variations on CO2 transport, injection, and storage, their characteristics must be known. We investigated variation characteristics in a scenario of a regional CO2 emitter cluster of seven fossil-fired power plants and four industrial plants that feed captured CO2 streams into a pipeline network. Variations of CO2 stream composition and mass flow rates in the pipelines were simulated using a network analysis tool. In addition, the potential effects of changes in the energy mix on resulting mass flow rates and CO2 stream compositions were investigated for two energy mix scenarios that consider higher shares of renewable energy sources or a replacement of lignite by hard coal and natural gas. While resulting maximum mass fl... [more]

When exposed to viscous heating, hydraulic valve orifices experience thermal deformation, which causes spool clamping and actuator disorder. Quantitative research on thermal deformation can help reveal the micro-mechanism of spool clamping. In this study, miniature thermocouples are embedded into a valve orifice with an opening size of 1 mm to measure temperature distribution. An optimization algorithm based on measurement data (M-OA) for the thermal deformation of the valve orifice is proposed. The temperature and thermal deformation of the valve orifice are calculated through Fluent and Workbench joint simulation, with the measurement data serving as boundary conditions. Results show that, for a valve orifice with a valve wall length of 18 mm, when the temperature of the sharp edge is at 60 °C, thermal deformation measures 7.7 μm via observation and 7.62803 μm via M-OA, indicating that the M-OA method is reliable. The results of the joint simulation can be accepted because measuremen... [more]

The development and application of emerging technologies of Industry 4.0 enable the realization of digital twins (DT), which facilitates the transformation of the manufacturing sector to a more agile and intelligent one. DTs are virtual constructs of physical systems that mirror the behavior and dynamics of such physical systems. A fully developed DT consists of physical components, virtual components, and information communications between the two. Integrated DTs are being applied in various processes and product industries. Although the pharmaceutical industry has evolved recently to adopt Quality-by-Design (QbD) initiatives and is undergoing a paradigm shift of digitalization to embrace Industry 4.0, there has not been a full DT application in pharmaceutical manufacturing. Therefore, there is a critical need to examine the progress of the pharmaceutical industry towards implementing DT solutions. The aim of this narrative literature review is to give an overview of the current statu... [more]