Multi-stage Mode Research Articles

ІНТЕНСИФІКАЦІЯ СУШІННЯ ЯБЛУК ПРИ КОНВЕКТИВНОМУ ТА КОМБІНОВАНОМУ СПОСОБАХ ЗНЕВОДНЕННЯ

The paper examines the intensification of drying apple slices to low residual moisture content. It is proposed to use an energy-efficient multi-stage mode of convective drying at 80/60 °C and a combined multi-stage mode with IR radiation and IR convective heating (100 W) + 60 °C / 60 °C. The paper presents the temperature and kinetic curves and changes in drying speed for the studied dehydration regimes. A formula was obtained for determining the total duration of the process of drying apple slices using a combined method, and a dependence of the Rebinder number for the studied dehydration modes was constructed. Based on the experimental data analysis and generalization of research results, a method of determining the drying intensity based on the average moisture exchange and the average temperature of material heating per minute, at the first stage of drying and during the entire drying time, was proposed for the first time. The efficacy of the proposed modes is confirmed by a reduction in drying duration 1.9 times compared to the stationary mode at a coolant temperature of 60 °C. The obtained dried product is characterized by high recoverability (78–80%) and appropriate organoleptic properties.

Effect of calcium on electrical resistance and phase composition of Al – 1.5 % Mn alloy

The authors used experimental and modelling techniques to look at the specific electrical resistance and phase composition of low-alloy Al – Ca – Mn alloys after they had been subjected to various annealing regimes. The study focused on four alloys in the form of ingots and cold-rolled sheets containing 1.5% Mn and up to 1% Ca. Templates cut out of ingots and sheets were annealed in a muffle furnace using multi-stage modes in the temperature range of 300 to 600 oC. They were soaked for 3 hours at each stage of the process and air cooled after each stage. It was found that, in the as-cast state, all manganese in all four alloys makes a part of the aluminium solution (Al), whereas calcium is comprised in the (Al) + Al4Ca eutectic, which agrees with the Sheil-Gulliver non-equilibrium solidification simulation. Annealing of cold-rolled sheets for 3 hours at 600 oC results in an equilibrium phase composition and a uniform structure – i. e. globular submicron particles evenly distributed throughout the aluminium matrix. In their initial state, when almost all Mn is comprised in (Al), the ingots and coldrolled sheets of all the studied alloys have little to no difference between each other in terms of specific electrical resistance. On the other hand, Ca helps to significantly lower the specific resistance (by 6 μΩ·mm) compared with the base alloy after cold-rolled sheets have been annealed at 350–400 oC. It may be attributed to a higher rate of aluminium solution breakdown, which is associated with a dropping concentration of Mn in (Al) and Al10CaMn2 particles forming in line with the Al – Ca – Mn phase diagram.This research was funded under Grant of the Russian Science Foundation N 20-19-00746.

Optimization-based technoeconomic comparison of multi-stage membrane distillation configurations for hypersaline produced water desalination

Unconventional oil and gas production raises concerns regarding sustainable management of high salinity wastewaters generated in this process. Membrane distillation (MD) is a thermal desalination process capable of treating hypersaline brines such as produced water. The low single pass recovery in MD systems operated in a single stage requires a large recycle stream to achieve the desired recovery, resulting in high energy consumption and operating cost. Multistage configurations in continuous recirculation operation mode offer the potential to reduce the energy intensity of MD systems. However, rigorous analysis is needed to assess the performance of MD configurations when operating in multi-stage mode. We present an optimization-based comparison of economic and energetic performance for five configurations of MD (including DCMD, AGMD, PGMD, CGMD, and VMD) operating in multi-stage continuous recirculation mode. Our findings demonstrate that multistage operation reduces the treatment cost and energy intensity of all MD configurations compared to single stage MD, with the greatest benefit for VMD and PGMD. AGMD with five stages outperforms other configurations with 3.58 $/m3feed treatment cost, followed by VMD, CGMD, DCMD, and PGMD with 3.8, 4.2, 5.4, and 9.06 $/m3feed treatment costs corresponding to twelve, eight, eight, and sixteen stages, respectively.

Predictive assessment from ANN and MLR models to optimize the ideal evaporative/hybrid cooler based on experimental observations

Single-stage evaporative coolers like a direct evaporative cooler (DEC) and indirect evaporative cooler (IEC) are not versatile in their applicability in diverse climatic conditions due to their dependency on local climatic variation. To overcome this, an indigenously designed three-stage cooling system capable of operating in single-stage modes like DEC, IEC, and direct expansion (DX), and multi-stage modes like IEC-DEC, DEC-DX, and IEC-DEC-DX is developed. Detailed energetic and exergetic investigations are conducted based on experimental data acquired from 20th-26th of each month from April to July 2019. The thermodynamic analyses lead to optimizing the ideal cooling system for tropical climate through the development and comparison of artificial neural network (ANN) and multiple linear regression (MLR) models by predicting the wet-bulb effectiveness (ε), coefficient of performance (COP), and exergy efficiency (ηex). The input parameters for the predictive models include ambient temperature, ambient relative humidity, conditioned air temperature, and corresponding relative humidity. Based on the predictions, it can be concluded that the ANN is superior to the MLR method for performance prediction, with a minimum mean square error. Although the IEC-DEC is observed ideal for tropical climate due to higher cooling capacity and COP in extreme summer, the efficacy of IEC-DEC-DX cannot be ignored for its all-weather competency. The ANN models predict thermodynamic performance parameters of proposed coolers within the error limit of ±10%.

Investigation of the Expression Method of Theme-Typhoon Disaster Information

Typhoon disaster information is characterized by multiple sources, complexity and diversity, and different users of this content have different individual concerns. The expression methods of typhoon disaster information considered in previous research have been relatively simple, which cannot meet the personalized service needs of different users. In this paper, according to the diverse content needs of different users in distinct stages of a typhoon disaster, a typhoon disaster information expression method with a multi-user, multi-stage, multi-channel and multi-element combined mode is investigated. First, the audience and disaster stages are divided via demand analysis, and the demand content is summarized according to the users, stages, and release channels. Similar information is then integrated into the same theme, and it is also determined how information is expressed. Then, the analytic hierarchy process (AHP) is used to filter out the important information in each theme. The theme template is then designed according to the characteristics of particular release channels. Finally, a prototype system is developed, and Typhoon Lekima, which impacted China in 2019, is considered as a real case for analysis. The results show that the proposed method can effectively support different users to obtain disaster characteristics at distinct stages of typhoon disasters, evaluate disaster conditions, assist scientific decision-making, and enhance public awareness of risk prevention.

Влияние искусственного старения на трещиностойкость листов высокопрочного алюминий-литиевого сплава B-1469

The effect of artificial aging modes on the structure, mechanical properties and crack resistance of sheets made from high-strength aluminum-lithium alloy V-1469 was studied. Kinetic curves of mechanical properties changes during artificial aging at various temperatures and long exposures were plotted. To establish the possibility of crack resistance increase the one-stage and multi-stage modes of artificial aging were selected for the study. As a result it was selected a mode that makes it possible to increase the crack resistance with a small decrease in strength, high corrosion resistance and fatigue life. Comparison of the structural-phase state and the complex of sheets properties processed by the selected mode with sheets processed by the mode providing maximum strength is made. The crack resistance, determined on large (750 mm wide) specimens from V-1469T1 alloy sheets processed according to the selected mode of aging, are at the level of sheets made from 1163AT type alloy. In opposite to high-strength aluminum alloy, when strength and crack resistance achieved by over-aging, the same properties in aluminum-lithium alloy V-1469 can be achieved by aging with short exposures.

Design of an Automatic Detector for Gas Desorption of Coal Samples

Gas content measurement is a common technique in the prevention of coalmine gas disasters. During the measurement, the gas desorption amount of field coal samples needs to be obtained by an instrument working under the principle of gas collection by water displacement (GCWD). The instrument is poorly automated, and susceptible to the influence of subjective factors. To overcome these defects, this paper designs an automatic detector of gas desorption, aiming to realize automated detection. Firstly, the authors analyzed the gas desorption detection process, and clarified the contents and features of the information to be collected. On this basis, the hardware and software systems of the multi-data automatic detector were developed based on digital circuit design and multi-sensor detection. To further improve the measuring accuracy of gas desorption, the multi-range multi-stage mode was introduced to the automatic detector. Application results show that the proposed detector can automatedly collect and store gas desorption amount, ambient pressure, and temperature, greatly improve the degree of automation, and minimize the influence of subjective factors. The popularization of this detector will make gas desorption measurement more efficient and effective, laying a solid basis for the prevention of coalmine gas disasters.

Causal effect analysis of logistics processes risks in manufacturing industries using sequential multi-stage fuzzy cognitive map: a case study

ABSTRACT Any shortage and deviation in the implementation of logistics processes can lead to a poor performance and losing the market share of the manufacturer. To overcome this problem, the identification of existing risks in all logistics sub-processes, and taking corrective/preventive measures, is of great importance. In this study, a risk prioritization approach is presented based on a sequential multi-stage fuzzy cognitive map (SMFCM) and process failure mode and effects analysis (PFMEA) to prioritize logistics processes risks. This approach, in addition to considering a process-oriented view, prioritizes the logistics risks according to the amount of each risk’s impact on other risks through the internal and external-stage causal relationships as well as the values of risk factors. The score obtained from this approach can create enough distinction among the priorities of different risks in comparison with conventional risk priority number (RPN). Also, the results based on this score have a lower dependency on experts’ opinions by applying the Extended Delta Rule (EDR) learning algorithm. In fact, the intelligent nature of this approach enables decision-makers to identify critical risks and examine the status of the system at any time. The results of the implementation of the SMFCM-PFMEA approach in a manufacturing company active in the automotive spare parts industry confirm the superiority of this compared with the conventional score.

On the energy release rate extraction and mixed mode behavior of fatigue cohesive model

This paper presents a comprehensive study on the energy release rate (ERR) extractions and mixed mode behavior of fatigue cohesive model. The development of the non-linear cohesive zone ahead of a crack tip is influenced by multiple factors, where the extractions of ERRs and mode ratios are crucial for accurate fatigue analysis in Paris law-based models. Investigations into the effects of different parameters e.g. interfacial strengths, shapes of the cohesive laws and element sizes on the extracted ERRs are conducted. In addition, two novel mixed mode bending models i.e. multi-stage mode ratio (MSMR) and continuously various mode ratio (CVMR) models are proposed for mixed-mode behavior study. All results are compared to the theoretical fracture mechanics analysis and to each other. It is found that if the interfacial strength becomes too low, an excessively long cohesive zone can form, where the mode ratio could significantly deviate from the true value and negatively impact the accuracy. The shape of cohesive laws is also found to influence the ERRs and mode ratios to some extent but are not the dominating factor.

Research on the passive nuclear level gauge

ABSTRACTUsing the ‘quadruple combination detection’ automatic calibration method to solve the traditional passive nuclear ash hopper material level meter calibration problem. The method adopts the ‘contour multistage measurement’ mode, fitted the ratio of absorbed dose rate detected by adjacent cascade probe with corresponding actual material level after measurement, then use the fitting parameters to calibrate automatically which do not need ash hopper stop working, And this can effectively save the calibration time and cost. The method can effectively eliminate the material level measuring error brought by the changes of radioactive activity in the coal ash, which improve the measuring precision and material level positioning accuracy. There are many factors affecting the radioactive activity of coal ash which vary in Different feeding period, or after refueling. And this may cause measurement error and misinformation. Using quadruple combination detection and contour multistage measurement mode, when the radioactive activity in the coal ash changes, the passive nuclear meter level gauge can be revised according to the calibration curve or calibrated automatically. Which eliminated the effects brought by the changing of coal ash radioactive activity, saved onerous repeatedly calibration procedure, also improve the accuracy of the calibration, avoid misjudgment, and can improve the accuracy of measurement.

Design and Test of a Single-Stage Double-Layer Multipole Field Electromagnetic Launcher With a Rotational Performance

A new type of multipole field electromagnetic launcher is designed in this paper, which has two parallel layers of multipole structure, and there is a 30-degree relative torsion angle between the inner and the outer one. The armature is designed as a complete and symmetrical hollow cylindrical metal sleeve with no slots. Owing to the superposition of the magnetic fields generated by the two layers, this novel structure can make the magnetic field density and eddy current distribution on the armature unbalanced, which generates an axial force and torque simultaneously. Simulations were conducted, and the magnetic field and the eddy current distribution were analyzed. The simulations indicate that this double-layer multipole field electromagnetic launcher achieves a rotational motion and a higher linear speed than that of single-layer structure. Experiments were performed and the results verified the correctness of the simulations. Due to its rotational performance, this configuration provides an approach to obtain gyroscopic stabilization for projectiles. It creates condition for multi-stage and combined mode applications because the armature does not need to be processed particularly to meet special requirements.

Combined Systems Approaches Reveal a Multistage Mode of Action of a Marine Antimicrobial Peptide against Pathogenic Escherichia coli and Its Protective Effect against Bacterial Peritonitis and Endotoxemia

ABSTRACTA marine arenicin-3 derivative, N4, displayed potent antibacterial activity against Gram-negative bacteria, but its antibacterial mode of action remains elusive. The mechanism of action of N4 against pathogenic Escherichia coli was first researched by combined cytological and transcriptomic techniques in this study. The N4 peptide permeabilized the outer membrane within 1 min, disrupted the plasma membrane after 0.5 h, and localized in the cytoplasm within 5 min. Gel retardation and circular dichroism (CD) spectrum analyses demonstrated that N4 bound specifically to DNA and disrupted the DNA conformation from the B type to the C type. N4 inhibited 21.1% of the DNA and 20.6% of the RNA synthesis within 15 min. Several hallmarks of apoptosis-like cell death were exhibited by N4-induced E. coli, such as cell cycle arrest in the replication (R) and division(D) phases, reactive oxygen species production, depolarization of the plasma membrane potential, and chromatin condensation within 0.5 h. Deformed cell morphology, disappearance of the plasma membrane, leakage of the contents, and ghost cell formation were demonstrated by transmission electron microscopy, and nearly 100% of the bacteria were killed by N4. A total of 428 to 663 differentially expressed genes are involved in the response to N4, which are associated mainly with membrane biogenesis (53.9% to 56.7%) and DNA binding (13.3% to 14.9%). N4-protected mice that were lethally challenged with lipopolysaccharide (LPS) exhibited reduced levels of interleukin-6 (IL-6), IL-1β, and tumor necrosis factor alpha (TNF-α) in serum and protected the lungs from LPS-induced injury. These data facilitate an enhanced understanding of the mechanisms of marine antimicrobial peptides (AMPs) against Gram-negative bacteria and provide guidelines in developing and applying novel multitarget AMPs in the field of unlimited marine resources as therapeutics.

Site-specific O-Glycosylation Analysis of Human Blood Plasma Proteins

Site-specific glycosylation analysis is key to investigate structure-function relationships of glycoproteins, e.g. in the context of antigenicity and disease progression. The analysis, though, is quite challenging and time consuming, in particular for O-glycosylated proteins. In consequence, despite their clinical and biopharmaceutical importance, many human blood plasma glycoproteins have not been characterized comprehensively with respect to their O-glycosylation. Here, we report on the site-specific O-glycosylation analysis of human blood plasma glycoproteins. To this end pooled human blood plasma of healthy donors was proteolytically digested using a broad-specific enzyme (Proteinase K), followed by a precipitation step, as well as a glycopeptide enrichment and fractionation step via hydrophilic interaction liquid chromatography, the latter being optimized for intact O-glycopeptides carrying short mucin-type core-1 and -2 O-glycans, which represent the vast majority of O-glycans on human blood plasma proteins. Enriched O-glycopeptide fractions were subjected to mass spectrometric analysis using reversed-phase liquid chromatography coupled online to an ion trap mass spectrometer operated in positive-ion mode. Peptide identity and glycan composition were derived from low-energy collision-induced dissociation fragment spectra acquired in multistage mode. To pinpoint the O-glycosylation sites glycopeptides were fragmented using electron transfer dissociation. Spectra were annotated by database searches as well as manually. Overall, 31 O-glycosylation sites and regions belonging to 22 proteins were identified, the majority being acute-phase proteins. Strikingly, also 11 novel O-glycosylation sites and regions were identified. In total 23 O-glycosylation sites could be pinpointed. Interestingly, the use of Proteinase K proved to be particularly beneficial in this context. The identified O-glycan compositions most probably correspond to mono- and disialylated core-1 mucin-type O-glycans (T-antigen). The developed workflow allows the identification and characterization of the major population of the human blood plasma O-glycoproteome and our results provide new insights, which can help to unravel structure-function relationships. The data were deposited to ProteomeXchange PXD003270.

A MULTISTAGE GRADUAL NITROGENREDUCTION STRATEGY FOR INCREASED LIPID PRODUCTIVITY AND NITROGEN REMOVAL IN WASTEWATER USING Chlorella vulgaris AND Scenedesmus obliquus

Chlorella vulgaris and Scenedesmus obliquuswere grown in artificial-wastewater using a new nitrogen-limitation strategy aimed at increasing lipid productivity. This strategy consisted in a multi-stage process with sequential reduction of N-NH4 concentration (from 90 to 60, 40, and 20 mg.L-1) to promote a balance between cell growth and lipid accumulation. Lipid productivity was compared against a reference process consisting of nitrogen reduction in two stages, where the nitrogen concentration was suddenly reduced from 90 mg.L-1 to three different concentrations (10, 20, and 30 mg.L-1). In the multi-stage mode, only C. vulgaris exhibited a net lipid-productivity increase. Lipid content of S. obliquus did not present a significant increase, thus decreasing lipid productivity. The highest lipid productivities were observed in the two-stage mode for both S. obliquus and C. vulgaris (194.9 and 133.5 mg.L-1.d-1, respectively), and these values are among the highest reported in the literature to date.

MATHEMATICAL MORPHOLOGY APPLIED IN RECOGNITION OF HEART SIGNS

The paper proposes an improved, efficient and low-power approach of processing in the digital filtering using mathematical morphology multistage mode for the detection of QRS complex in the ECG signal.

MATHEMATICAL MORPHOLOGY APPLIED IN RECOGNITION OF HEART SIGNS

The paper proposes an improved, efficient and low-power approach of processing in the digital filtering using mathematical morphology multistage mode for the detection of QRS complex in the ECG signal.

Advancement of Al – Li alloys and of multistage modes of their heat treatment

Third-generation aluminum alloys 1441, 1424 and V-1461, V-1469 of medium and high strength, respectively, which have been developed as an alternative to the base aluminum alloys 1163 and V95 widely used in the aircraft industry, are studied. The advantages of the suggested alloys with respect to the strength, life characteristics, weldability and corrosion resistance are shown.

Modeling and Modal Analysis of Less-Teeth Gear Shaft

As the less-teeth gear has the less-teeth, the bigger helix angle and the more contact ratio etc. The research of dynamic meshing characteristics makes focus, and modal analysis is the basis of dynamic analysis. In order to get the modal analysis characteristics: firstly the parametric solid modeling is realized through the software of MATLAB and PRO/E; secondly multistage inherent frequencies and mode shapes are achieved by the finite element software of ANSYS Workbench.

Effects of random stiffness variations in multistage rotors using the Polynomial Chaos Expansion

The paper presents a methodology that allows the investigation of the effects of random uncertainties on the global dynamics of multistage bladed discs systems. Uncertainties are accounted for as variations in the material properties of the blades. The multistage cyclic symmetry assumption is used to reduce the global problem. The random dynamics of the global system is obtained by applying the Polynomial Chaos Expansion. The methodology is applied to a two stage bladed disc assembly and the results of modal and forced response analysis are validated by comparisons with Monte-Carlo simulations. Possible interactions of multistage mode families in zones of high modal density due to uncertainties in the blades are discussed. Results obtained show that uncertainties may induce significant changes in the global dynamics of multistage assemblies and the proposed technique is shown to be efficient to capture those changes. The study classically evaluates the variations of frequencies and responses but also shows that the nature of mode shapes may be drastically affected by uncertainties.

Comparative Lipidomic Profiling of S. cerevisiae and Four Other Hemiascomycetous Yeasts.

Glycerophospholipids (GP) are the building blocks of cellular membranes and play essential roles in cell compartmentation, membrane fluidity or apoptosis. In addition, GPs are sources for multifunctional second messengers. Whereas the genome and proteome of the most intensively studied eukaryotic model organism, the baker’s yeast (Saccharomyces cerevisiae), are well characterized, the analysis of its lipid composition is still at the beginning. Moreover, different yeast species can be distinguished on the DNA, RNA and protein level, but it is currently unknown if they can also be differentiated by determination of their GP pattern. Therefore, the GP compositions of five different yeast strains, grown under identical environmental conditions, were elucidated using high performance liquid chromatography coupled to negative electrospray ionization-hybrid linear ion trap-Fourier transform ion cyclotron resonance mass spectrometry in single and multistage mode. Using this approach, relative quantification of more than 100 molecular species belonging to nine GP classes was achieved. The comparative lipidomic profiling of Saccharomyces cerevisiae, Saccharomyces bayanus, Kluyveromyces thermotolerans, Pichia angusta, and Yarrowia lipolytica revealed characteristic GP profiles for each strain. However, genetically related yeast strains show similarities in their GP compositions, e.g., Saccharomyces cerevisiae and Saccharomyces bayanus.