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Records Added in 2023
Records added in 2023
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Showing records 36187 to 36211 of 36336. [First] Page: 1 1445 1446 1447 1448 1449 1450 1451 1452 1453 Last
36187. LAPSE:2023.0707
A Modified Multiparameter Linear Programming Method for Efficient Power System Reliability Assessment
February 20, 2023 (v1)
Subject: Optimization
Keywords: computational complexity, multiparameter linear programming, optimal power flow, power system reliability, state reduction
Power systems face adequacy risks because of the high integration of renewable energy. It is urgent to develop efficient methods for power system operational reliability assessment. Conventional power system reliability assessment methods cannot achieve real-time assessment of system risk because of the high computational complexity and long calculation time. The high computational complexity is mainly caused by a large number of optimal power flow (OPF) calculations. To reduce the computational complexity, this paper transfers the optimal power flow model as a multiparameter linear programming model. Then, the optimal power flow can be obtained by linear calculations. Furthermore, this paper proposes a state reduction method considering the importance index of transmission lines for further improving the calculation efficiency. Case studies are carried out on IEEE standard systems and a provincial power grid in China. Compared with the conventional reliability assessment method, the r... [more]
36188. LAPSE:2023.0706
High-Temperature Pyrolysis for Elimination of Per- and Polyfluoroalkyl Substances (PFAS) from Biosolids
February 20, 2023 (v1)
Subject: Environment
Keywords: biochar, biosolids, high-temperature pyrolysis, PFAS, thermal treatment
Biosolids generated as byproducts of wastewater treatment processes are widely used as fertilizer supplements to improve soil condition and ultimately agricultural products yields and quality. However, biosolids may contain toxic compounds, i.e., per- and polyfluoroalkyl substances (PFAS), which can end up in soils, groundwater, and surface water, causing adverse environmental and health effects. The purpose of this study was to investigate the application of High-Temperature Pyrolysis (HTP) treatment for biosolids management, and its efficacy in eliminating PFAS from the solid fraction. Biosolid samples were pyrolyzed at two different temperatures, 500 and 700 °C, in a continuous bench-scale pyrolysis unit. The major finding is that the treatment process at higher pyrolysis temperatures can remarkably reduce or eliminate the level of PFAS (by ~97−100 wt%) in the resulting biochar samples.
36189. LAPSE:2023.0666
Omega-3 Fatty Acid Retention and Oxidative Stability of Spray-Dried Chia−Fish-Oil-Prepared Microcapsules
February 20, 2023 (v1)
Subject: Materials
Keywords: fatty acid loss, omega-3 fatty acids, oxidative stability, spray drying conditions
Background: Omega-3 fatty acids are essential fatty acids that the body cannot create itself; thus, they must be obtained from functional foods. Therefore, the food processing industries are becoming more interested in the production of omega-3 enriched food products, as consumers and healthcare organizations are increasingly demanding functional foods with minimal fatty acid loss and higher oxidative stability. Moreover, the stability of long-chain, polyunsaturated fatty acids in functional foods is a major challenge for the food processing industries. Therefore, the spray drying method was used to prepare spray-dried microcapsules (SDMs) with the minimum loss of, and more stable, fatty acids. Methods: In this study, emulsion blends of chia seed oil (CSO, 50%) and fish oil (FO, 50%) were spray-dried using varied operating conditions, including the inlet air temperature (IAT) (125, 140, 155, 170, and 185 °C), wall material (WM) (5, 10, 15, 20, and 25%), pump speed (PS) (3, 4, 5, 6, and... [more]
36190. LAPSE:2023.0665
Coal-Scenedesmus Microalgae Co-Firing in a Fixed Bed Combustion Reactor: A Study on CO2, SO2 and NOx Emissions and Ash
February 20, 2023 (v1)
Subject: Environment
Keywords: ash residue, co-firing, Coal, greenhouse gas emissions, Scenedesmus microalgae
This study investigated the effect of coal−Scenedesmus microalgae (with blending ratios of 100:0 (coal), 95:5 (Coalgae® 5%), 90:10 (Coalgae® 10%), 85:15 (Coalgae® 15%) and 80:20 (Coalgae® 20%)) on combustion temperature, mass loss, the formation of CO2, SO2 and NOx gases, and ash content under constant atmospheric air flow. Coalgae® refers to a material formed after blending coal and microalgae. The results showed that NOx came mainly from Coalgae® 10% and 15%, and this observation could be attributed to a variable air concentration level (O2 level) in the environment that could influence NOx during the combustion process, irrespective of the blending ratios. CO2 emission reductions (12%, 17%, 21% and 29%) and SO2 emission reductions (3%, 12%, 16% and 19%) increased with the increasing coal-microalgae blending ratio (Coalgae® 5−20%), respectively. Bubble-like morphology was observed in the ash particles of coal−microalgae blends through SEM, while the TEM confirmed the formation of car... [more]
36191. LAPSE:2023.0664
Effect of Poultry Manure-Derived Compost on the Growth of eucalypts spp. Hybrid Clones
February 20, 2023 (v1)
Subject: Process Design
Keywords: forest valorization, substrates, vegetative propagation
Interspecific hybrids of E. grandis × E. camaldulensis were generated to widen the plantation area. The aim of this study was to assess root capability and development for six different clones of eucalyptus grown in substrates made with three different composts derived from poultry manure. A factorial design was used to assess the effect of different composts on six growth variables. The analysis detected a greater effect from the genotype than the substrate. E. grandis × E. camaldulensis hybrid vegetative propagation was successful in alternative substrates formulated from composted poultry manure. GC8 was the genotype that showed the greatest differences for four the different variables among the substrates, being both the most sensitive and the one with the highest values for all parameters measured. The hybrids’ vegetative propagation was determined in alternative substrates formulated from poultry manure compost. The physicochemical characteristics of substrates composed of pine b... [more]
36192. LAPSE:2023.0663
Monitoring the Recombinant Adeno-Associated Virus Production using Extended Kalman Filter
February 20, 2023 (v1)
Subject: Numerical Methods and Statistics
Keywords: Bayesian inference, extended Kalman filter, neural ordinary differential equation, parameter estimation, rAAV production supervision, unstructured mechanistic kinetic model
The recombinant adeno-associated virus (rAAV) is a viral vector technology for gene therapy that is considered the safest and most effective way to repair single-gene abnormalities in non-dividing cells. However, improving the viral titer productivity in rAAV production remains challenging. The first step to this end is to effectively monitor the process state variables (cell density, GLC, GLN, LAC, AMM, and rAAV viral titer) to improve the control performance for an enhanced productivity. However, the current approaches to monitoring are expensive, laborious, and time-consuming. This paper presents an extended Kalman filter (EKF) approach used to monitor the rAAV production using the online viable cell density measurements and estimating the other state variables measured at a low frequency. The proposed EKF uses an unstructured mechanistic kinetic model applicable in the upstream process. Three datasets were used for parameter estimation, calibration, and testing, and the data were c... [more]
36193. LAPSE:2023.0662
Recent Advances in the Equal Channel Angular Pressing of Metallic Materials
February 20, 2023 (v1)
Subject: Materials
Keywords: deformation mechanism, ECAP, grain size, metallic materials, processing parameters
Applications of a metallic material highly depend on its mechanical properties, which greatly depend on the material’s grain sizes. Reducing grain sizes by severe plastic deformation is one of the efficient approaches to enhance the mechanical properties of a metallic material. In this paper, severe plastic deformation of equal channel angular pressing (ECAP) will be reviewed to illustrate its effects on the grain refinement of some common metallic materials such as titanium alloys, aluminum alloys, and magnesium alloys. In the ECAP process, the materials can be processed severely and repeatedly in a designed ECAP mold to accumulate a large amount of plastic strain. Ultrafine grains with diameters of submicron meters or even nanometers can be achieved through severe plastic deformation of the ECAP. In detail, this paper will give state-of-the-art details about the influences of ECAP processing parameters such as passes, temperature, and routes on the evolution of the microstructure of... [more]
36194. LAPSE:2023.0661
Stochastic Allocation of Photovoltaic Energy Resources in Distribution Systems Considering Uncertainties Using New Improved Meta-Heuristic Algorithm
February 20, 2023 (v1)
Subject: Modelling and Simulations
Keywords: distribution system, improved human learning optimization algorithm, monte carlo simulation, stochastic-metaheuristic model, uncertainty
In this paper, a stochastic-metaheuristic model is performed for multi-objective allocation of photovoltaic (PV) resources in 33-bus and 69-bus distribution systems to minimize power losses of the distribution system lines, improving the voltage profile and voltage stability of the distribution system buses, considering the uncertainty of PV units’ power and network demand. The decision-making variables, including installation location and the size of PVs, are determined optimally via an improved human learning optimization algorithm (IHLOA). The conventional human learning optimization algorithm (IHLOA) is improved based on Gaussian mutation to enhance the exploration capability and avoid getting trapped in local optimal. The methodology is implemented in two cases as deterministic and stochastic without and with uncertainties, respectively. Monte Carol Simulation (MCS) based on probability distribution function (PDF) is used for uncertainties modeling. The deterministic results prove... [more]
36195. LAPSE:2023.0660
Statistical Optimisation of Used-Cooking-Oil Degradation by Burkholderia vietnamiensis AQ5-12 and Burkholderia sp. AQ5-13
February 20, 2023 (v1)
Subject: Numerical Methods and Statistics
Keywords: biodegradation, Burkholderia sp., Burkholderia vietnamiensis, one-factor-at-time (OFAT), response-surface methodology (RSM), used cooking oil
Used cooking oil (UCO) is a hydrocarbon that causes significant environmental pollution globally. Oil is a difficult pollutant to remove from the environment due to its hydrophobic nature. Bioremediation is preferred over chemical and physical remediation approaches as it is more economical and environmentally friendly. Hence, the search for a microbe with outstanding degrading capability is imperative due to the nature of hydrocarbons as pollutants. The current study evaluates the ability of glyphosate degrader isolates, Burkholderia vietnamiensis AQ5-12 and Burkholderia sp. AQ5-13, to degrade UCO as the sole carbon source. The physico-cultural conditions affecting the activities of the isolates were studied using one-factor-at-a-time (OFAT) and response-surface methodology (RSM). The temperature, agitation speed, UCO concentration, nitrogen supply, yeast extract concentration, and inoculum size were optimised during a 7-day incubation period. Based on the OFAT results, the highest de... [more]
36196. LAPSE:2023.0659
Autoignition of Methane−Hydrogen Mixtures below 1000 K
February 20, 2023 (v1)
Subject: Modelling and Simulations
Keywords: autoignition delay time, Hydrogen, kinetic modeling, methane, methane–hydrogen mixtures
In the range of 800−1200 K, both experiments and kinetic modeling demonstrate a significant difference in the dependence of the ignition delay time of methane and hydrogen on pressure and temperature, with the complex influence of these parameters on the autoignition delay time of methane−hydrogen−air mixtures. In connection with the prospects for the widespread use of methane−hydrogen mixtures in energy production and transport, a detailed analysis of their ignition at temperatures below 1000 K, the most important region from the point of view of their practical application, is carried out. It is shown that such a complex behavior is associated with the transition in this temperature range from low-temperature mechanisms of oxidation of both methane and hydrogen, in which peroxide radicals and molecules play a decisive role, to high-temperature mechanisms of their oxidation, in which simpler radicals dominate. A kinetic interpretation of the processes occurring in this case is propose... [more]
36197. LAPSE:2023.0658
Hydrothermal In-Reservoir Upgrading of Heavy Oil in the Presence of Non-Ionic Surfactants
February 20, 2023 (v1)
Subject: Energy Systems
Keywords: aquathermolysis, asphaltenes, enhanced oil recovery, heavy oil, non-ionic surfactant, steam injection
The most widely applied methods to unlock heavy oil and natural bitumen resources in the world are still based on steam injection techniques. Improving the efficiency of hydrothermal processes poses a great challenge. The co-injection of various additives is practiced to lower the steam-to-oil ratio (SOR), viscosity alteration and to improve heavy oil properties. Organic solvents, non-condensable gases, air and surfactants are the preferred chemicals to be combined with steam. This study provides an investigation of the surfactant-assisted hydrothermal upgrading of heavy oil at 200 °C. The thermal stability and salt resistivity of two non-ionic surfactants (SA−3 and Biolub Green) were investigated. Moreover, the improved performance of the surfactants was established by performing an SARA analysis, elemental analysis, FT-IR spectroscopy, and EPR analysis, and by studying the viscosity reduction degree. The experimental results showed that surfactants lead to the in-depth destructive hy... [more]
36198. LAPSE:2023.0657
Autonomous Surveillance for an Indoor Security Robot
February 20, 2023 (v1)
Subject: Modelling and Simulations
Keywords: Artificial Intelligence, deep learning, face recognition, mobile robots, object detection, simultaneous localization and mapping
Conventional surveillance for a security robot suffers from severe limitations, perceptual aliasing (e.g., different places/objects can appear identical), occlusion (e.g., place/object appearance changes between visits), illumination changes, significant viewpoint changes, etc. This paper proposes an autonomous robotic system based on CNN (convolutional neural network) to perform visual perception and control tasks. The visual perception aims to identify all objects moving in the scene and to verify whether the target is an authorized person. The visual perception system includes a motion detection module, a tracking module, face detection, and a recognition module. The control system includes motion control and navigation (path planning and obstacle avoidance). The empirical validation includes the evaluation metrics, such as model speed, accuracy, precision, recall, ROC (receiver operating characteristic) curve, P-R (precision−recall) curve, F1-score for AlexNet, VggNet, and GoogLeNe... [more]
36199. LAPSE:2023.0655
Quality Changes of Low-Density Polyethylene (LDPE) Recyclates from the Pretreatment Process with a Cationic Surfactant and a Nonionic Surfactant as Cleaning Agents Upstream of Extrusion
February 20, 2023 (v1)
Subject: Materials
Keywords: cleaning, LDPE, mechanical recycling, pretreatment, surfactant
Low-density polyethylene is the most applied packaging plastic. The recycling rate of LDPE is low, especially for the material from the post-consumer source. The quality of the LDPE post-consumer recyclates is influenced by different contaminations, either intentionally or non-intentionally. Printing ink is one of the substances that is regarded as having a negative influence on the quality of LDPE recyclates. This study used a new type of nonionic surfactant oxirane, methyl-, polymer for de-inking as a pretreatment. Afterward, the LDPE film flakes were mechanically recycled in the laboratory. A melt flow index (MFI), differential scanning calorimetry (DSC), and tensile strength analysis were carried out. This work reported the de-inking effect of a new type of nonionic surfactant. However, no evidential correlation between the rate of color removal and the improvement in the rheological, thermal, and mechanical properties can be identified from the result of this study.
36200. LAPSE:2023.0654
Integration of Maintenance Management System Functions with Industry 4.0 Technologies and Features—A Review
February 20, 2023 (v1)
Subject: Energy Systems
Keywords: Industry 4.0, integration, Maintenance 4.0, maintenance engineering, maintenance management systems, predictive maintenance
Industry 4.0 is the latest technological age, in which recent technological developments are being integrated within industrial systems. Consequently, maintenance management of current industrial manufacturing systems is affected by the emergence of the technologies and features of Industry 4.0. This study aimed to conduct a comprehensive literature review to understand how Industry 4.0 technologies and features affect the various functions of maintenance management systems. The reviewing process was initiated by examining the most recent related literature in three different databases. In total, 54 articles were classified into three research categories. Then, the integration of the main functions and components of the adopted maintenance management model and the Industry 4.0 features and technologies were aligned, focusing on the driving force of predictive maintenance. The analysis focused mainly on the technical aspects of the integration process, including integration concepts and... [more]
36201. LAPSE:2023.0653
Numerical Prediction of the Performance of Chamfered and Sharp Cutting Tools during Orthogonal Cutting of AISI 1045 Steel
February 20, 2023 (v1)
Subject: Modelling and Simulations
Keywords: ANOVA, numerical simulation, orthogonal cutting, stress, temperature, tool edge preparation, tool wear
This paper presents a numerical investigation of the effects of chamfered and sharp cemented carbide tools using finite element method-based DEFORM-2D software and cutting parameters on different machining characteristics during the orthogonal cutting of AISI 1045 steel. The objective is to study the interactions between chamfer width, chamfer angle, sharp angle and the cutting speed and feed rate on the cutting temperature, effective stress and wear depth. These effects were investigated statistically using the analysis of variance (ANOVA) test. The obtained numerical results showed that for the chamfer tool, high values of temperature, stress and wear depth were obtained for chamfer widths of 0.35 mm and 0.45 mm. In terms of combined influences, for the cutting temperature and stress, a strong interaction between the cutting speed and chamfer width was obtained. For the sharp tool design, and in terms of temperature, strong interactions are mostly observed between cutting speeds and... [more]
36202. LAPSE:2023.0652
Jamun (Syzygium cumini (L.) Skeels) Seed: A Review on Nutritional Profile, Functional Food Properties, Health-Promoting Applications, and Safety Aspects
February 20, 2023 (v1)
Subject: Food & Agricultural Processes
Keywords: functional ingredient, industrial application, jamun seeds, toxicity
Jamun (Syzygium cumini L. Skeels) is highly perishable with a very short shelf life, hence, jamun fruit is either consumed fresh as soon as it is harvested or converted to value-added products such as jam, wine, juice, and jellies. The processing of jamun fruit generates a large quantity of seeds as the primary waste. Jamun seeds are a rich source of macronutrients such as carbohydrates, proteins, lipids, minerals, and vitamins, thus making them an important ingredient in the food industry. The valorization of underutilized, nutritionally rich byproducts of the food processing industry has been providing new ways for unlocking their potential in the functional food industry or therapeutic food formulations. This review presents a detailed nutritional profile of jamun seeds and its potent application in the food industry as a possible functional ingredient. Along with its beneficial nutritional profile, the review also throws light upon the safety aspects associated with jamun seed cons... [more]
36203. LAPSE:2023.0651
Possible Processes and Mechanisms of Hexachlorobenzene Decomposition by the Selected Comamonas testosteroni Bacterial Strains
February 20, 2023 (v1)
Subject: Biosystems
Keywords: bacterial decomposition, destroying activity, destruction potential, hexachlorobenzene, microbial metabolism, toxicity
: The bacterial destructing activity toward pesticides has been the focus of research in the last few decades. Hexachlorobenzene is included in the organochlorine pesticides group that are prohibited for use. However, large hexachlorobenzene amounts are still concentrated in the soil, stressing the relevance of research on hexachlorobenzene-destroying bacteria.: The ability to destroy hexachlorobenzene by Comamonas testosteroni UCM B-400, B-401, B-213 strains was investigated and established. Bacteria were cultivated (7 days at 28 °C) in mineral Luria-Bertrani (LB) medium with three hexachlorobenzene doses: 10, 20, 50 mg/L. The hexachlorobenzene concentrations were recorded by a gas chromatography method.: The results showed that C. testosteroni UCM B-400, B-401 have high destructive activity toward hexachlorobenzene. The highest (50 mg/L) initial concentration decreased to 41.5 and 43.8%, respectively, for C. testosteroni UCM B-400, B-401. The unadapted C. testosteroni UCM B-213 was t... [more]
36204. LAPSE:2023.0650
Dynamic Risk Assessment of High Slope in Open-Pit Coalmines Based on Interval Trapezoidal Fuzzy Soft Set Method: A Case Study
February 20, 2023 (v1)
Subject: Numerical Methods and Statistics
Keywords: dynamic risk assessment, high slope, open-pit coalmine, safety management and control
Effective high slope risk assessment plays an important role in the safety management and control of the open-pit coal mining process. Traditional slope stability risk assessment methods rarely consider the time factor or evaluate the dynamic change of high slope in an open-pit mine at a certain time in a sensitivity assessment. This paper develops an interval trapezoidal fuzzy soft set method to achieve the high slope dynamic risk evaluation. The proposed dynamic interval trapezoidal fuzzy soft set method for risk assessment of high slope in an open-pit coal mine is developed by integrating the time points and weights of slope risk factors. The extended interval trapezoidal fuzzy soft set was used to calculate the weights of risk factors at different times, and the Fuzzy Analytical Hierarchy Process (FAHP) method was applied to determine the weights of risk factors. The weight change of different risk factors with time can be easily achieved with the proposed method. As a case study,... [more]
36205. LAPSE:2023.0649
Microwave-Hydrogen Peroxide Assisted Anaerobic Treatment as an Effective Method for Short-Chain Fatty Acids Production from Tannery Sludge
February 20, 2023 (v1)
Subject: Environment
Keywords: anaerobic fermentation, biorefinery, short chain fatty acids (SCFAs), tannery sludge
Tannery sludge is disposed of in landfills as it is considered a special residue by the Italian legislation, creating pollution and waste. This paper aims at evaluating the performance of the anaerobic fermentation process to obtain short-chain fatty acids (SCFAs) from this waste. The assessment of the most appropriate conditions, in terms of pH, temperature, initial total solids (TSs) content, and application of oxidizing-thermal pretreatment has been developed. The batch test trials revealed that the combined microwave and hydrogen peroxide (MW-H2O2) pretreatment followed by thermophilic conditions gave the best results, in terms of the acidification yield (0.31 gCODSCFA/gVS0) and maximal SCFA concentration (above 26 g CODSCFA/L). In the tests conducted without pretreatment, the mesophilic temperature should be preferred since the acidification performances were comparable to or even better than their thermophilic counterparts. The SCFA composition analysis showed that in mesophilic... [more]
36206. LAPSE:2023.0648
The Estimation of Centrifugal Pump Flow Rate Based on the Power−Speed Curve Interpolation Method
February 20, 2023 (v1)
Subject: Numerical Methods and Statistics
Keywords: centrifugal pump, flow estimation, PN curves interpolation, sensorless
During the global energy crisis, it is essential to improve the energy efficiency of pumps by adjusting the pump’s control strategy according to the operational states. However, monitoring the pump’s operational states with the help of external sensors brings both additional costs and risks of failure. This study proposed an interpolation method based on PN curves (power−speed curves) containing information regarding motor shaft power, speed, and flow rate to achieve high accuracy in predicting the pump’s flow rates without flow sensors. The impact factors on the accuracy of the estimation method were analyzed. Measurements were performed to validate the feasibility and robustness of the PN curve interpolation method and compared with the QP and back-propagation neural network (BPNN) methods. The results indicated that the PN curve interpolation method has lower errors than the other two prediction models. Moreover, the average absolute errors of the PN curve interpolation method in th... [more]
36207. LAPSE:2023.0647
Identification of the Elemental Composition of Granulated Blast Furnace Slag by FTIR-Spectroscopy and Chemometrics
February 20, 2023 (v1)
Subject: Materials
Keywords: chemical composition, chemometrics, infrared spectroscopy, metallurgical slag, PCR, PLS
Blast furnace slag is a key large-tonnage waste product of metallurgical production, which is considered to be a promising alternative material in construction. In order to determine the scope of potential use of slag as a marketable product, it is necessary to study its structure and composition, which is determined by means of modern analytical instrumental methods. This paper analyzes the application of Fourier transform infrared spectroscopy (FTIR) and chemometrics methods to develop calibration models for identifying pelletized slag by elemental composition. In a comparative analysis of FTIR-spectra of slag the characteristic frequencies of absorption bands responsible for the content of calcite, silicates and aluminosilicates in the composition of samples were determined. Multivariate regression methods (principal components regression, partial least squares regression) and data of elemental composition results by EDX method were used to develop calibration models for determining... [more]
36208. LAPSE:2023.0646
Assessment and Removal of Heavy Metals and Other Ions from the Industrial Wastewater of Faisalabad, Pakistan
February 20, 2023 (v1)
Subject: Environment
Keywords: Adsorption, biosorbent, industrial, Monotheca buxifolia, Wastewater
The contamination of surface and groundwater is of major concern around the globe due to the fast industrialization and urbanization. The groundwater and water quality of rivers, Ravi and Chenab in Faisalabad, Pakistan are contaminated due to the industrial wastewater. The aim of this study was the assessment of the physiochemical contaminants of Faisalabad’s industrial wastewater area and the adsorptive removal of ions present in high concentrations following the National Environmental Quality Standards (NEQS) for the municipal and industrial liquid effluents of Pakistan. One of the two samples was collected from a drain carrying wastewater from different industries and other from the outlet of a drain discharging wastewater into river Chenab. The analysis results obtained indicate that most of the contaminants were below the acceptable limit of industrial wastewater NEQS, Pakistan. However, contaminants like sulfate ions (714 mg/L), total dissolved solids (33,951−34,620 mg/L) and bar... [more]
36209. LAPSE:2023.0645
Hybrid Diesel/PV Multi-Megawatt Plant Seasonal Behavioral Model to Analyze Microgrid Effectiveness: Case Study of a Mining Site Electrification
February 20, 2023 (v1)
Subject: Energy Systems
Keywords: behavior models, hybrid micro grid, performance index, photovoltaic/diesel plant, power transients management
Mining sites that combine energy-intensive operations with community living in areas remote from the electricity grid are increasingly developing dedicated micro-grids. Fossil oil gensets hybridization with renewable energy resources has gained momentum. Difficulties in assessing performance are experienced by operators who wish to benefit from improved performances. The designers of such systems also need additional knowledge to anticipate the solutions of the particular problems related to the power plant’s implementation area characteristics. The proposed approach gives more suitable tools on the effectiveness evaluation of hybridized microgrid, combining a Heavy Fuel Oil (HFO) thermal power station with photovoltaic generator powering mine activities in the Sahelian area. The authors provide key analyses and improvement factors by seasonal behavioral modelling (SBM) of the fuel consumption of the gensets related to the overall irradiance dynamics of the PV array. Several years of d... [more]
36210. LAPSE:2023.0644
Diesel Engine Fault Diagnosis Method Based on Optimized VMD and Improved CNN
February 20, 2023 (v1)
Subject: Process Control
Keywords: continuous wavelet transform, convolutional neural network, diesel engine fault diagnosis, support vector machine, variational mode decomposition
The safe operation of diesel engines performs a vital function in industrial production and life. Because diesel engines often work in harsh environmental conditions, they are prone to failure. Therefore, this paper proposes a fault analysis method based on a combination of optimized variational mode decomposition (VMD) and improved convolutional neural networks (CNN) to address the necessary need for preventive maintenance of diesel engines. The authentic vibration sign is first decomposed by using the (VMD) algorithm, then the greatest range of decomposition layers is decided by using scattering entropy and the useful components are preferentially chosen for reconstruction. The continuous wavelet transform (CWT) records preprocessing method is then delivered to radically change the noise-reduced vibration sign into a time-frequency map, which is fed into the CNN for model coaching and extraction of fault features. Finally, fault classification is realized by support vector machine (S... [more]
36211. LAPSE:2023.0643
Separation of Molar Weight-Distributed Polyethylene Glycols by Reversed-Phase Chromatography—Analysis and Modeling Based on Isocratic Analytical-Scale Investigations
February 20, 2023 (v1)
Subject: Materials
Keywords: Modelling, monodisperse PEG, polyethylene glycol, reversed-phase chromatography, thermodynamic analysis
The separation of polyethylene glycols (PEGs) into single homologs by reversed-phase chromatography is investigated experimentally and theoretically. The used core−shell column is shown to achieve the baseline separation of PEG homologs up to molar weights of at least 5000 g/mol. A detailed study is performed elucidating the role of the operating conditions, including the temperature, eluent composition, and degree of polymerization of the polymer. Applying Martin’s rule yields a simple model for retention times that holds for a wide range of conditions. In combination with relations for column efficiency, the role of the operating conditions is discussed, and separations are predicted for analytical-scale chromatography. Finally, the approach is included in an efficient process model based on discrete convolution, which is demonstrated to predict with high accuracy also advanced operating modes with arbitrary injection profiles.

