Saturation Phenomenon Research Articles

BRIDGED INTERSECTIONS AND ITS ROLE IN SOLVING THE PROBLEM OF TRAFFIC JAMS IN BAGHDAD (ADEN INTERSECTION AS A MODEL)

The phenomenon of traffic saturation experienced by intersections and roads leading to those intersections and the areas connecting them, has become a daily phenomenon experienced by road users and intersections. It is a problem that all intersections of the city of Baghdad suffer from because of the suffering of all roads from the problem of heavy roads in Baghdad, which is traffic congestion, a phenomenon that has become part of the life of Iraqi society and as a result of the limited solutions available as a result of the conflict of most of the proposed projects with the infrastructure of the city of Baghdad, in addition to the high financial cost of their implementation, As well as the development of new residential areas and commercial activities in places that prevent the implementation of some of the proposed projects, especially that this phenomenon exceeded expectations and studies devoted to the basic design of the city of Baghdad after the events of 2003 as a result of the development and economic openness that the country witnessed and the resulting increase in the number of vehicles in a disproportionate manner and the absorption of roads for them, in addition To the increase in population numbers and the expansion and emergence of new residential areas and the consequent activities and services that exacerbated this problem. Through our research and the importance of intersections in the flow of vehicles in the roads leading to the intersection and the surrounding areas, the study sought to determine the effectiveness and success of the traffic performance of the intersection after diversion into a bridge, in terms of the ease of vehicle flow, the lack of waiting time for one vehicle, and the organization of movements for the different directions of the intersection.

A Nonlinear SRM Controller Design for Torque Ripple Reduction with accounting for Magnetic Saturation

In this paper, a nonlinear backstepping controller design is proposed for torque ripple minimization in switched reluctance motor (SRM) drive systems, which ensures less acoustic noise and less vibration. The proposed controller is based on a model taking into account the stator coils magnetic saturation phenomenon. For the torque ripple optimization purpose, the excitation angles are adapted according to the instantaneous SRM torque and speed values. Therefore, a lookup table is built, proposing the excitation angles optimal values for different machine operation points. The proposed control strategy validation was carried out by simulation, using MATLAB-Simulink tools. More specifically, the Simpower system library was exploited, since it offers an SRM simulator, taking into account magnetic saturation. To highlight the supremacy of the proposed controller, its performances are compared with those of conventional linear (PI) regulator. The obtained results validate the proposed controller robustness and efficiency.

Hypermedia and Recursive Mediatization of the Corporate News

The article analyzes some trends in the dynamics of deep mediatization processes. The phenomenon of saturation of standard formats for presenting news with unexpected references, which transform the communication system, is revealed. For the correct interpretation of the discovered phenomena, the concept of hypermedia is used as an aspect of deep mediatization of the relationship between the company and its stakeholders. The model of recursive communication is concretized. The central point is the thesis about the self-applicability of the recursive method of studying the communication field. The influence of digital platforms algorithms on the daily practices of users has been investigated. The conclusions are formulated from an ecological point of view, highlighting the importance of creating an effective environment for corporate relations. The author believes that the transition to trans-disciplinary methods of researching the problems of deep mediatization in the digital era is inevitable. The role of philosophical reflection in determining the key areas of research is especially emphasized.

Improvement of Wheat Grain Yield Prediction Model Performance Based on Stacking Technique

Crop growth and development is a dynamic and complex process, and the essence of yield formation is the continuous accumulation of photosynthetic products from multiple fertility stages. In this study, a new stacking method for integrating multiple growth stages information was proposed to improve the performance of the winter wheat grain yield (GY) prediction model. For this purpose, crop canopy hyperspectral reflectance and leaf area index (LAI) data were obtained at the jointing, flagging, anthesis and grain filling stages. In this case, 15 vegetation indices and LAI were used as input features of the elastic network to construct GY prediction models for single growth stage. Based on Stacking technique, the GY prediction results of four single growth stages were integrated to construct the ensemble learning framework. The results showed that vegetation indices coupled LAI could effectively overcome the spectral saturation phenomenon, the validated R2 of each growth stage was improved by 10%, 22.5%, 3.6% and 10%, respectively. The stacking method provided more stable information with higher prediction accuracy than the individual fertility results (R2 = 0.74), and the R2 of the model validation phase improved by 236%, 51%, 27.6%, and 12.1%, respectively. The study can provide a reference for GY prediction of other crops.

Impacts of electrode shape on lithiation performance: the edge effect on lithium intercalation

With respect to the increasing applications of irregular shape electrodes in stretchable and flexible batteries, the impacts of electrode shape on lithiation performance are investigated in this manuscript. Firstly, square and circular side-to-side electrodes are prepared and employed for charge and discharge cycles. The lithiation profiles of the graphite electrode are in-situ observed and the electrochemical cyclic performances are recorded. It is found uneven lithiation is more significant in the square electrode than the circular electrode, leading to more side reaction products and poorer cyclic performance. Numerical simulations are conducted to investigate the intrinsic mechanism of the uneven lithiation. It is found the electric field is extraordinarily strong near the electrode edges, resulting in highly inhomogeneous lithium flux in electrolyte. The electrode edges are exposed to excessive lithium supply in electrolyte, leading to fast lithiation saturation and even lithium dendrite growth. Meanwhile, the core area of the electrode cannot obtain sufficient lithium from electrolyte and, therefore, remain in low lithiation level even after charge operation. The sharper the electrode tip is, the stronger the edge effect is. Finally, different irregular shape face-to-face electrodes are prepared and examined. The edge effects are also found in the face-to-face electrodes and lead to a fake lithiation saturation phenomenon. Therefore, strategies to minimize the edge effects, such as decreasing the curvatures of the electrode sharp tips, are suggested to promote the electrochemical performance.

Prediction of Ship Heave Motion Using Regularized BP Neural Network with Cross Entropy Error Function

Accurate prediction of ship’s heave motion can greatly enhance the safety of offshore operation. Due to its complexity and nonlinearity, however, ship’s heave motion prediction is a difficult task to be solved. In this paper, a new method for predicting ship’s heave motion is proposed based on an improved back propagation neural network (IBPNN). To overcome the gradient saturation phenomenon of traditional BPNN, the mean square error (MSE) loss function is replaced with a cross entropy (CE) loss function in IBPNN. Meanwhile, the weights of IBPNN is regularized by L_2 norm to enhance the generalization ability of traditional BPNN. Finally, conjugate gradient method is adopted to train IBPNN. The IBPNN is used to predict ship’s heave motion and the prediction results prove its effectiveness.

Quantumized Microwave Detection Based on Λ-Type Three-Level Superconducting System: HMM Modeling and Performance Prediction

We adopt artificial <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Lambda $ </tex-math></inline-formula> -type three-level system with superconducting devices for microwave signal detection, where the signal intensity reaches the level of discrete photons instead of continuous waveform. Based on the state transition principles of the three-level system, we propose a statistical model for microwave signal detection. In addition, achievable transmission rates and signal detection based on the proposed statistical models are investigated for low temperature conditions in deep space communication scenario. It is predicted that high sensitivity can be achieved by the proposed system. We further characterize the received signal considering the saturation phenomenon of three-level system, which reveals negligible performance degradation caused by saturation under weak received power regime.

Research on Adaptive Hybrid Energy Consumption Model Based on Data Driven under Variable Working Conditions

As to the nonlinear and time-varying problems of the energy consumption model, this paper proposes an adaptive hybrid modeling method. Firstly, the recursive least squares algorithm with adaptive forgetting factor based on fuzzy algorithm and recursive least squares algorithm is used to identify the simplified mechanism energy consumption model, which solves the data saturation phenomenon and the weights of the “old and new” data during the online identification process and guarantees the adaptability of the mechanism model. Secondly, because there is a deviation between the identified model and the simplified mechanism energy consumption model, the deviation compensation model of mechanism model is established through kernel partial least squares algorithm and the model updating strategy with sliding window, which is used to update the deviation compensation model, and then the adaptive hybrid model is established by combining with the mechanism model identified online and updated deviation compensation model. Finally, the effectiveness, generalization and adaptability of the model are verified by the actual operating data of a single working condition and variable working conditions. And comparing with the mechanism model and the data model, The comparison results show that the adaptive hybrid model has higher calculation accuracy with adaptation.

Photosynthesis, Growth and Dry Biomass Production in Euglena gracilis Klebs as Affected by Three Growth Irradiance Levels

Aims: The research aimed to investigate the shade response of E. gracilis Klebs while making the irradiance a crucial factor for photosynthesis based physiological activities and its applicability for industrial level culture conditions.&#x0D; Study Design: Euglena was cultured at three different light intensities of 30, 90, and 210 mol m-2s-1 photoautotrophically and axenically in modified Cramer-Meyer medium at 25 ˚C as batch cultures.&#x0D; Methodology: The photosynthesis O2 evaluation of Euglena cultures was measured under exponential (EP), transitional (TP), and stationary phases (SP). The light compensation point (LCP), light saturation point (LSP), and dark respiration rate (DRR) were obtained. Cell volume and cell number in each culture were measured simultaneously. Cells were collected and obtained dry mass (DM) after drying aliquots at 80˚C. Specific growth rate (SGR) and relative growth rate (RGR) were calculated. Tests for homogeneity of variance were performed on all parameters and LSDs were used for the mean separation.&#x0D; Results: In the TP, the lowest LCP was achieved in the higher light culture. The values of both the DRR and the LSP were the same as in EP. The DRR, LCP and LSP are lower in lower PFD cultures and decreased with increasing cell titers. The cellular growth levels were lower in lower light culture and decreased as each culture grew. Cellular DM was maintained constant in the EP, where SGR almost equaled RGR. In the EP, SGR was maintained constant in each culture, SGR displayed a saturation phenomenon. In the later TP, SGR became equal to RGR and all the cultures revealed constant DM.&#x0D; Conclusion: Euglena photoautotrophic cultures can tolerate low light intensities. With the SGR and RGR behavior under the shade conditions, they can maintain the constant photosynthesis rate and constant dry matter level.

A novel underdamped continuous unsaturation bistable stochastic resonance method and its application

In view of the saturation problem of classical bistable stochastic resonance (CBSR) system, an underdamped continuous unsaturation bistable stochastic resonance (UCUBSR) system is investigated and the feasibility of the system for weak fault feature extraction is discussed. Firstly, based on the reason of saturation phenomenon, a new potential function is constructed, which can independently adjust the steepness of the potential walls. The signal to noise ratio (SNR) of the system is derived. Secondly, a modified unsaturation index, amplitude gain, is proposed, and the influence of the steepness on SR based on SNR and amplitude gain is analyzed. The simulation analysis shows that the amplitude gain can be considered as an appropriate index to quantify SR and has a certain compensation effect on the SNR applied to evaluate unsaturation performance. Finally, from the simulation and experiment, a larger amplitude gain indicates that the proposed system has better unsaturation and weak fault detection ability compared with unsaturation bistable stochastic resonance (UBSR), and a higher amplitude of the output signal at the characteristic frequency proves that the amplitude gain as an indicator can further guide the parameter adjustment of SR and facilitate faint fault signature identification.

Hybrid modelling of saturated water flow in percolating and non-percolating macroporous soil media

The saturated water flow phenomenon is determined by the soil pore transport processes occurring at a micro-scale. In this study, saturated water flow was modeled using two different approaches, depending on the existence of the percolating macropore network. The soil material comprised 26 undisturbed soil cores. Soil samples were scanned using an X-ray micro-CT scanner, and saturated hydraulic conductivity (Ksat), bulk density and particle size distribution were measured. The voxel size for X-ray CT scans of soil cores was 23.6 µm, which allowed soil macropore network discrimination. The macropore network was percolating in 11 samples, while the remaining cores were not. A typical approach based on Navier–Stokes (NS) equations was used for saturated water flow modeling in the case of a percolating samples. In the case of cores with a non-percolating macropore network, the NS modeling approach could not be used. An alternative method of modeling (NS/Darcy) was used in this case, blending: regular NS flow in the well-defined macropores with the Darcy–Forchheimer flow in the remaining part – the soil matrix. Soil matrix is treated by the NS/Darcy model as a pore medium without well-defined pore geometry but with some intrinsic permeability incorporated in the model using the Darcy–Forchheimer equation. Unlike the NS approach, the NS/Darcy model allowed for the simulation of water flow for all soil samples, including those where the macropore network was not percolating. Based on simulations, the Ksat was estimated used for model validation. The analysis of results leads to the proposal of a new hybrid modeling approach, mixing the NS and NS/Darcy modeling approaches. A good estimation of the Ksat was obtained using the proposed model (R2 = 0.61). The NS/Darcy modeling approach was used for the analysis of the macropore flow in the soil media. The simulations show that water permeates through the core, but macropores are a favorable flow path if they exist, even if they are not directly connected to each other. The areas of the soil cores taking part in the preferential, macropore flow were quantified, showing that only a small fraction of the macropores take part in water flow both for percolating and non-percolating cores. But generally, for most of the analyzed flow-related indices, apparent differences in results between percolating and non-percolating samples were observed. Effective flow area (EFA), i.e., the sample area used for water flow with a velocity higher than the threshold velocity (Utr) was analyzed. Considering the macropore flow, only ∼2% of sample volume is responsible for: 82% of the total flux in case of percolated and 34% in case of non-percolated samples. Also, for non-percolated samples, the dependence (R2 = 0.44) between relative flux participation and the effective flow area is observed. The simulation results for the non-percolating samples revealed the relationship between the simulated saturated conductivity of the whole soil sample and the saturated conductivity of the soil matrix and macroporosity. This allowed for developing a simple multiple linear regression model (R2 = 0.98) of the soil core’s hydraulic conductivity.

Mining for Gluon Saturation at Colliders

Quantum chromodynamics (QCD) is the theory of strong interactions of quarks and gluons collectively called partons, the basic constituents of all nuclear matter. Its non-abelian character manifests in nature in the form of two remarkable properties: color confinement and asymptotic freedom. At high energies, perturbation theory can result in the growth and dominance of very gluon densities at small-x. If left uncontrolled, this growth can result in gluons eternally growing violating a number of mathematical bounds. The resolution to this problem lies by balancing gluon emissions by recombinating gluons at high energies: phenomena of gluon saturation. High energy nuclear and particle physics experiments have spent the past decades quantifying the structure of protons and nuclei in terms of their fundamental constituents confirming predicted extraordinary behavior of matter at extreme density and pressure conditions. In the process they have also measured seemingly unexpected phenomena. We will give a state of the art review of the underlying theoretical and experimental tools and measurements pertinent to gluon saturation physics. We will argue for the need of high energy electron-proton/ion colliders such as the proposed EIC (USA) and LHeC (Europe) to consolidate our knowledge of QCD knowledge in the small x kinematic domains.

Formation and evolution of fracture spacing on various geometric surfaces in layered materials

Fracture spacing as a widespread phenomenon in nature shows similar patterns on various geometric surfaces. To explore the similarities and differences between various geometric surfaces in the process of fracture spacing formation, numerical simulations are conducted on bi-layered three-dimensional models of three various geometric surfaces, including slab surface, cylindrical surface, and spherical surface by the finite element method (FEM). The fractures develop under a quasi-static loading condition with constant displacement increments. The progressive failure process from fracture initiation to saturation is researched, and the material heterogeneity is introduced by using a probability distribution, which acts as the main reason for failures generating randomly inception. An intuitive explanation is also provided for the phenomenon of fracture saturation. Then, as the loading condition varies, fracture patterns in both slab surface models and cylindrical surface models show a transition from parallel fractures, step-like fractures to regular polygonal fractures. However, in spherical surface models, only uniform polygonal fractures emerge under the condition of radial expansion. Furthermore, through quantitative analysis by statistical means, we find that, except for the fractured layer thickness, curvature also has a significant impact on the crack density.

Synchronization of coupled reaction–diffusion neural networks via intermittent control and saturated impulses

The impulsive synchronization of coupled neural networks with input saturation and the term of reaction–diffusion via a hybrid control strategy is investigated. In this paper, a hybrid controller is proposed, including impulsive controller with input saturation and intermittent controller. This type of hybrid controller can not only solve the periodic and aperiodic intermittent control, lower the update frequency of the controller, but also avoid the saturation phenomenon of impulsive control. Based on linear matrix inequalities (LMIs), and Jensen’s inequality, under a proposed suitable Lyapunov function, a series of sufficient conditions are established to guarantee the stability of the error system. Compared with the recent relevant impulsive saturation results, the polytopic representation method dealing with actuator saturation may make the synchronization criterion more universal and less restrictive. Finally, a numerical example is provided to verify the correctness and feasibility of the theoretical results.

Sartre and Marion on Intentionality and Phenomenality

This article offers a reading of Jean-Paul Sartre’s phenomenology in light of Jean-Luc Marion’s more recent phenomenology. It may seem odd to compare Sartre to Marion, given that Sartre is well-known for his avowed atheism and his account of intentionality while Marion is primarily known for his work on religious phenomena and counter-intentionality. However, this article shows that there are many ways in which Sartre anticipates Marion’s work on phenomenological reduction and excessive phenomenality. By reading Sartre’s phenomenology in light of Marion’s, and particularly Sartre’s analysis of the viscous slime in Being and Nothingness in relation to Marion’s account of ‘saturated phenomena’, this article presents a fresh interpretation of Sartre as a phenomenologist who has invaluable insights not only on the structures of consciousness and phenomenality, but also for the contemporary theoretical interest in the relationship between human and nonhuman entities.

High responsivity graphene-InGaAs near-infrared photodetector realized by hole trapping and its response saturation mechanism.

Graphene is an ideal material for wide spectrum detector owing to its special band structure, but its low light absorption and fast composite of photogenerated carriers lead to a weak response performance. In this paper, we designed a unique photoconductive graphene-InGaAs photodetector. The built-in electric field was formed between graphene and InGaAs, which can prolong the lifetime of photogenerated carriers and improve the response of devices by confining the holes. Compared with graphene-Si structure, a higher built-in electric field and reach to 0.54 eV is formed. It enables the device to achieve a responsivity of 60 AW-1 and a photoconductive gain of 79.4 at 792 nm. In the 1550 nm communication band, the responsivity of the device is also greater than 10 AW-1 and response speed is less than 2 ms. Meanwhile, the saturation phenomenon of light response was also found in this photoconductive graphene heterojunction detector during the experiment, we have explained the phenomenon by the capacitance theory of the built-in electric field, and the maximum optical responsivity of the detector is calculated theoretically, which is in good agreement with the measurement result.

On the saturated impulse for a circular hollow beam under pressure pulse loading

The saturated impulse phenomenon, which may occur in a hollow beam with a circular cross-section, is examined when a rectangular pressure pulse loading is applied uniformly on the upper surface of the beam. A simplified 2DoF model of the dynamic response of a relatively long circular hollow section beam is developed to explore the role of the local and global deformations build up simultaneously during the beam response. In order to simplify the analytical formulation, the elastic deformations of the hollow beam are neglected, and a rigid-plastic method of analysis is applied. Finite element simulations using an elastic, perfectly plastic material model are carried out to verify the proposed analytical model and to reveal the influence of the elasticity on the beam response. The limit of the pressure pulse loading, beyond which saturated impulse is not defined for a hollow beam, is obtained numerically. The responses of hollow beams with lengths between 800 and 1200 mm, radius of 40 mm and several wall thicknesses are analysed. It is observed that the proposed 2DoF model can predict satisfactory the local and global saturated deflections while the saturated pressure pulse duration is underestimated due to the disregard of the stored elastic energy in the beam. It is suggested that the analytically predicted saturated impulse can be used as a lower bound estimate for the saturated impulse for a given beam geometry.

Delineation of the flow and mixing induced by Rayleigh–Taylor instability through tracers

Rayleigh–Taylor-instability (RTI) induced flow and mixing are of great importance in both nature and engineering scenarios. To capture the underpinning physics, tracers are introduced to make a supplement to discrete Boltzmann simulation of compressible RTI flows. By marking two types of tracers with different colors, the tracer distribution provides a clear boundary of two fluids during the evolution. Fine structures of RTI flow and thermodynamic non-equilibrium behavior around the interface in a miscible two-fluid system are delineated. Distribution of tracers in their velocity phase space makes a charming pattern showing quite dense information on the flow behavior, which opens a new perspective for analyzing and accessing significantly deep insights into the flow system. RTI mixing is further investigated via tracer-defined local mixedness. The appearance of Kelvin–Helmholtz instability is quantitatively captured by the abrupt increase in mixedness averaged along the direction of acceleration. The role of compressibility and viscosity on mixing are investigated separately, both of which show a two-stage effect. The underlying mechanism of the two-stage effect is interpreted as the development of large structures at the initial stage and the generation of small structures at the late stage. At the late stage, for a fixed time, a saturation phenomenon of viscosity is found that a further increase in viscosity cannot lead to an evident decline in mixedness. The mixing statues of heavy and light fluids are not synchronous and the mixing of an RTI system is heterogeneous. The results are helpful for understanding the mechanism of flow and mixing induced by RTI.

Event-triggered model predictive control of positive systems with random actuator saturation.

This paper investigates the event-triggered model predictive control of positive systems with actuator saturation. Interval and polytopic uncertainties are imposed on the systems, respectively. First, a new model with actuator saturation obeying Bernoulli distribution is established, which is more general and powerful for describing the saturation phenomenon than the saturation in a deterministic way. Then, a linear event-triggering condition is constructed based on the state and error signal. Under the event-triggering condition, an interval estimate approach is presented to reach the positivity and stability of the systems. The saturation part in the controller is technically transformed into a non-saturation part. Thus, a linear programming approach is proposed to compute the event-triggered controller gain and the corresponding gain of attraction domain. A predictive algorithm is introduced for the computation of the event-triggered controller parameters. Finally, an example is provided to illustrate the validity of the design.

Facilitated transport membranes for H2 purification from coal-derived syngas: A techno-economic analysis

A single-stage membrane process has been designed for using facilitated transport membranes (FTMs) to decarbonize the coal-derived syngas from an integrated gasification combined cycle (IGCC) power plant. The necessary process model and costing method have also been developed to assess the technical feasibility and process economics. In order to account for the carrier saturation phenomenon associated with FTMs, a homogeneous reactive diffusion model is integrated into the process model. The techno-economic study reveals that the mitigated carrier saturation upon bulk CO2 removal can lead to appreciable increases in the CO2 permeance and CO2/H2 selectivity, which can be utilized to achieve 95% CO2 purity and 95% H2 recovery with a CO2/H2 selectivity of 50 at the complete carrier saturation. FTMs with different facilitated transport characteristics can also be arranged in a hybrid membrane configuration to render a H2 recovery of 99% and a cost of electricity of $118.5/MWh, which is 12.5% lower than that of the benchmark Selexol process.